Datasets:

Trelis

/

big_patent_100k_characters

like 1

Follow

Trelis 83

CROSS-REFERENCE TO RELATED APPLICATIONS [0001] This application is a National Stage Appl. filed under 35 USC 371 of International Patent Application No. PCT/CN2012/073075 with an international filing date of Mar. 27, 2012, designating the United States, and further claims priority benefits to Chinese Patent Application No. 201110094974.7 filed Apr. 15, 2011. The contents of all of the aforementioned applications, including any intervening amendments thereto, are incorporated herein by reference. Inquiries from the public to applicants or assignees concerning this document or the related applications should be directed to: Matthias Scholl P. C., Attn.: Dr. Matthias Scholl Esq., 14781 Memorial Drive, Suite 1319, Houston, Tex. 77079. BACKGROUND OF THE INVENTION [0002] 1. Field of the Invention [0003] The invention relates to the signal system design and signal generation of a satellite navigation system, and more particularly to a method and system for modulating navigation signal. [0004] 2. Description of the Related Art [0005] At present, signal modulation of satellite navigation has been developed from the first generation of BPSK modulation used by GPS into new modulation systems such as BOC, CBOC, TMBOC, and AltBOC. The AltBOC modulation system can bear different services in the upper and lower sidebands, which can not only receive and handle SSB signals independently to achieve the traditional BPSK signal performance, but also realize joint treatment to achieve higher positioning accuracy. Therefore, the AltBOC modulation system has been adopted by the COMPASS global system as the baseline for the modulation system of downgoing signals at the B2 frequency point. [0006] AltBOC is a quasi BOC modulation system of which the upper and lower sidebands can modulate different pseudo-codes. AltBOC was first put forward in 2000, targeting to convey dual line navigation signals using one HPA on E1 and E2 frequency bands. However, owing to the non-constant envelope and signal planning and adjustment at L1 frequency band, AltBOC modulation system is not applied to L1 frequency band. In 2001, CNES put forward the AltBOC modulation system with 4-pseudo-code constant envelope, and was adopted as the modulation mode of navigation signal at GalileoE5a and E5b frequency band. [0007] In COMPASS system, AltBOC ( 15 , 10 ) modulation system whose center frequency is 1,191.795 MHz is adopted. The center frequency of a lower sideband is 1,176.45 MHz and that of an upper sideband is 1,207.14 MHz. This can not only realize the interoperation with GalileoE5 and GPSL5C signals, but also consider the compatibility with B2 signal in COMPASS district system. However, in order to achieve the modulation through 4-pseudo-code constant envelope, the AltBOC modulation system put forward by Galileo improves the conversion rate of baseband waveform to 8 times of the subcarrier, improves the level number of subcarrier to 4, and inserts product terms. The increase in baseband conversion rate and level of subcarrier will in no doubt multiply the complexity of signal generation and receiving. Introduction of product terms can reduce the multiplexing efficiency, which, to a certain extent, reduces the signal performance. With the smart design, CNES can keep the signal component near the subcarrier frequency not reduced, and ensure the performance of receiver is not damaged even when it only receives the main lobe power. However, the harmonic component of subcarrier can only modulate the useless product signals, so it reduces the performance under broadband receiving conditions. SUMMARY OF THE INVENTION [0008] In view of the above-described problems, it is one objective of the invention to provide a method and system for modulating navigation signal. The method and system has the advantages of flexible reception and treatment of signals, high MUX efficiency, and low complexity in signal generation, reception, and treatment. [0009] To achieve the above objectives, in accordance with one embodiment of the invention, there is provided a method for modulating navigation signal, the method comprising the following steps: [0010] 1) dividing frequency of a control clock CLK 0 to obtain a pseudo-code generating drive clock CLK 1 and a time division multiplexing (TDM) control clock CLK 2 , where, a frequency of the control clock CLK 0 is four times that of a binary subcarrier, a frequency of the pseudo-code generating drive clock CLK 1 is ½ of a code rate, and a frequency of the TDM control clock CLK 2 is equivalent to the code rate; [0011] 2) driving the CLK 1 to generate pseudo-code c BD of a data channel of an upper sideband, pseudo-code c AD of a data channel of a lower sideband, and pseudo-code c P of a pilot channel; driving the CLK 0 to generate a binary sine subcarrier SC B, sin and a binary cosine subcarrier SC B, cos ; [0012] 3) modulating the c AD by a lower sideband d A to generate a baseband signal component C A of the data channel of the lower sideband; modulating the c BD by an upper sideband waveform d B to generate a baseband signal component C B of the data channel of the upper sideband; [0013] 4) modulating the subcarriers, which comprising: (4.1) negating the C A and adding to the C B , and multiplying with the SC B, sin to get a signal component of data channel at Q branch; adding the C A to the C B and multiplying with the SC B, cos to get a signal component of data channel at I branch; multiplying the C P by 2 and then multiplying with the SC B, cos to get a signal component of the pilot channel at I branch; (4.2) when the CLK 2 is in a time slot of odd chip, allowing the signal component of the data channel at Q branch to be a signal component of a baseband signal at Q branch, and allowing the signal component of the data channel at I branch to be a signal component of a baseband signal at I branch; when CLK 2 is in a time slot of even chip, allowing zero signal to be the signal component of the baseband signal at Q branch, and allowing the signal component of the pilot channel at I branch to be the signal component of the baseband signal at I branch; and [0016] (5) modulating a sine phase carrier by the signal component of the baseband signal at Q branch, modulating a cosine phase carrier by the signal component of the baseband signal at I branch, and combining the modulation result of the two branches to obtain a modulated radio frequency signal. [0017] In step (4), corresponding baseband signal components at Q branch and I branch are looked up in a modulation mapping table according to the current C A , C B , and C P value; a method to establish the modulation mapping table comprises: combining all possible C A , C B and C P values and processing each combination thereof according to steps (4.1)-(4.2) to get the baseband signal component at Q branch and I branch corresponding to each combination, and recording each combination and corresponding Q branch component and I branch component thereof to establish the modulation mapping table. [0018] The invention provides a system for modulating navigation signal according the above-mentioned method. The system comprises: [0019] a first multiplier 3 , a first subtracter 4 , a second multiplier 7 , and a first time division multiplexer 11 , which are connected in order; [0020] a fourth multiplier 2 , a second adder 5 , a fifth multiplier 8 , and a second time division multiplexer 12 , which are connected in order; [0021] a seventh multiplier 6 and an eighth multiplier 9 connected in order; [0022] a pseudo-code generator 1 connected to the first multiplier 3 , the fourth multiplier 2 , and the seventh multiplier 6 ; [0023] a first frequency divider 17 connected to the pseudo-code generator 1 ; [0024] a subcarrier generator connected to the second multiplier 7 , the fifth multiplier 8 , and the eighth multiplier 9 ; [0025] a second frequency divider 18 connected to the first time division multiplexer 11 and the second time division multiplexer 12 ; [0026] the first multiplier 3 is connected to the second adder 5 ; the fourth multiplier 2 is connected to the first subtracter 4 ; the eighth multiplier 9 is connected to the second time division multiplexer 12 ; the first time division multiplexer 11 and second time division multiplexer 12 are connected to a RF modulator; the first time division multiplexer 11 receives zero signal input. [0027] The invention further provides a system for modulating navigation signal according the above-mentioned method. The system comprises: [0028] a frequency divider 24 and a pseudo-code generator 19 , which are connected; the pseudo-code generator 19 is connected to a first input terminal of a baseband modulation module 26 through a first Exclusive-OR operator 20 ; the pseudo-code generator 19 is connected to a second input terminal of the baseband modulation module 26 through a second Exclusive-OR operator 21 ; the pseudo-code generator 19 is also connected to a third input terminal of the baseband modulation module 26 ; the two output terminals of TD-AltBOC baseband modulation module 26 are connected to a RF modulator. [0029] Advantages of the invention are summarized as follows. [0030] The time-domain characteristics of TD-AltBOC modulating signal in the invention are as follows: within the odd time slot, the baseband wave form at I and Q branch is decided by the pseudo-code c BD of data channel of the upper sideband and the pseudo-code c AD of data channel of the lower sideband; when C BD =0 and C AD =0, the baseband wave form at I branch appears as binary cosine subcarrier, and the baseband wave form at Q branch is 0; when C BD =1 and C AD =1, the baseband wave form at I branch appears as reverse binary cosine subcarrier, and the baseband wave form at Q branch is 0; when C BD =0 and C AD =1, the baseband wave form at I branch is 0, and the baseband wave form at Q branch appears as binary sine subcarrier; when C BD =1 and C AD =0, the baseband wave form at I branch is 0, and the baseband wave form at Q branch appears as reverse binary sine subcarrier. Within the even time slot, the baseband wave form at Q branch is 0, and the baseband wave form at I branch is decided by the pseudo-code C P of pilot channel; when C P =0, the baseband wave form at I branch appears as binary cosine subcarrier; when C P =1, the baseband wave form at I branch appears as reverse binary cosine subcarrier. The baseband wave form of TD-AltBOC modulating signal is shown in FIG. 5 . The baseband signal waveform of TD-AltBOC ( 15 , 10 ) modulation is shown in FIG. 5 . [0031] The power spectrum of TD-AltBOC modulating signal comprises two main lobes; wherein, the spectral peak of one main lobe is located at where the carrier frequency is added to the subcarrier frequency; it is mainly the signal component of the upper sideband. The spectral peak of the other main lobe is located at where the carrier frequency is subtracted by the subcarrier frequency; it is mainly the signal component of the lower sideband. The normalized power spectrum of TD-AltBOC ( 15 , 10 ) modulating signal is shown in FIG. 6 . [0032] TD-AltBOC modulating signal possesses favorable flexibility in reception. Signal of the upper sideband can be taken as the BPSK (Rc) modulating signal of which the center frequency is equal to the carrier frequency plus subcarrier frequency; signal of the lower sideband can be taken as the BPSK (Rc) modulating signal of which the center frequency is equal to the carrier frequency subtracted by subcarrier frequency. Signal of the upper and lower sidebands can be respectively received, thereby obtaining the receptivity equivalent to BPSK (Rc); signal of the upper and lower sidebands can also be received jointly, thereby obtaining the receptivity equivalent to BOC (fs, Rc). [0033] TD-AltBOC modulating signal possesses 100% multiplexing efficiency. Adopting time division technique can realize the constant envelope multiplexing of the 4 signal components at the upper and lower sidebands; the product signal component is not introduced, so there is no multiplexing loss. [0034] As for complexity, the pilot channels of upper and lower sidebands of TD-AltBOC share the same pseudo-code, joint receiving of the double side band is equivalent to cosine BOC modulation, and the number of pseudo-code generator and correlator required by pilot signal track can be halved; the conversion rate of TD-AltBOC subcarrier symbol is four times of the subcarrier frequency, while the conversion rate of AltBOC subcarrier symbol is eight times of the subcarrier frequency; the baseband processing rate for signal generation is halved; the waveform of TD-AltBOC subcarrier is 2 level; the waveform of AltBOC subcarrier is 4 level; fewer hardware resources will be consumed by a single correlator during matched receiving; during the time-sharing appearance of data channel and pilot channel of TD-AltBOC modulating signal, some elementary units (such as multiplier) which consume more hardware resources can realize time-sharing multiplexing, thereby improving the resource utilization rate and reducing the consumption of hardware resources. Therefore, the complexity of generation and receiving of TD-AltBOC signal is far below that of AltBOC signal. BRIEF DESCRIPTION OF THE DRAWINGS [0035] FIG. 1 shows sequential relationship of transmission of TD-AltBOC signal components; [0036] FIG. 2 shows a diagram of generation of TD-AltBOC modulating signal; [0037] FIG. 3 shows the generation of TD-AltBOC modulating signal; and [0038] FIG. 4 shows planisphere and waveform of TD-AltBOC modulation. DETAILED DESCRIPTION OF THE EMBODIMENTS [0039] The invention combines the TDM mode by chip and 2-signal AltBOC modulation system, which solves the problem in 4-signal constant envelope modulation; it is named as Time Division AltBOC mode, short for TD-AltBOC. [0040] I. TD-AltBOC Principle [0041] Parameter definition of TD-AltBOC (m, n) modulation: m refers to the multiple of f 0 , the relative reference frequency of subcarrier frequency, namely f s =m×f 0 ; n refers to the multiple of f 0 , relative reference frequency of code rate, namely, R c =n×f 0 . [0042] TD-AltBOC modulation divides the signal transmission time into odd and even time slots. The time slot width equals to the pseudo-code chip width. The odd time slot transmits the signal component of data channel of the upper and lower sidebands; and, the even time slot transmits the signal component of pilot channel of the upper and lower sidebands. The sequential relationship for signal component transmission is shown in FIG. 1 . [0043] In FIG. 1 , B2b_D refers to the signal component of data channel of the upper sideband; B2b_P refers to the signal component of pilot channel of the upper sideband; B2a_D refers to the signal component of data channel of the lower sideband; B2a_P refers to the signal component of pilot channel of the lower sideband. [0044] The mathematical representation of TD-AltBOC modulating baseband signal is [0000] s ( t )=[d A ( t ) c AD ( t )+ c AP ( t )][ SC b, cos ( t )− jSC b, sin ( t )]+[ d B ( t ) c BD ( t )+ c BP ( t )][ SC B, cos ( t )+ jSC B, sin ( t )] [0000] wherein, d A (t) is the data bit waveform of modulation of data channel of the lower sideband; c AD (t) is the pseudo-code waveform of data channel of the lower sideband; c AP (t) is the pseudo-code waveform of data channel of the lower sideband; d B (t) is the data bit waveform of modulation of data channel of the upper sideband; c BD (t) is the pseudo-code waveform of data channel of the upper sideband; c BP (t) is the pseudo-code waveform of data channel of the upper sideband; SC B, cos (t) is binary cosine subcarrier; SC B, sin (t) is binary sine subcarrier. They are: [0000] c AD  ( t ) = ∑ l = - ∞ ∞  ∑ k = 0 N AD - 1  C AD  ( k )  p  ( t - ( 2  N AD  l + 2  k )  T c ) c AP  ( t ) = ∑ l = - ∞ ∞  ∑ k = 0 N AP - 1  C AP  ( k )  p  ( t - ( 2  N AP  l + 2  k + 1 )  T c ) c BD  ( t ) = ∑ l = - ∞ ∞  ∑ k = 0 N BD - 1  C BD  ( k )  p  ( t - ( 2  N BD  l + 2  k )  T c ) c BP  ( t ) = ∑ l = - ∞ ∞  ∑ k = 0 N BP - 1  C BP  ( k )  p  ( t - ( 2  N BP + 2  k + 1 )  T c ) SC B , cos  ( t ) = sign  ( cos  ( 2  π   f s  t ) ) SC B , sin  ( t ) = sign  ( sin  ( 2  π   f s  t ) ) [0045] wherein, C AD is the pseudo-code sequence of data channel of the lower sideband (take ±1); C AP is the pseudo-code sequence of pilot channel of the lower sideband; C BD is the pseudo-code sequence of data channel of the upper sideband; c BP is the pseudo-code sequence of pilot channel of the upper sideband; N AD , N AP , N BD and N BP are respectively the code length of C AD , C AP , C AP and C BP ; T c is the pseudo-code chip width; p({tilde over (t)}) is square topped pulse; sign (•) means the symbolic operation; f s is subcarrier frequency (B2 signal is 15×1.023 MHz). p({tilde over (t)}) is defined as follows [0000] p  ( t ) = { 1 0 ≤ t ~ < T c 0 others [0046] The planisphere and signal waveform of TD-AltBOC modulating signal are shown in FIG. 4 . [0047] In FIG. 4 , C A and C B respectively refer to the pseudo-code of lower sideband and upper sideband transmitted in a certain time slot. When the present time slot is odd time slot, C A =d A C AD , C B =d B C BD ; when the present time slot is even time slot, C A =C AP , C B =C BP . The signal waveform depicted in real line is same-phase branch waveform; the signal waveform depicted in dotted line is perpendicular branch waveform. [0048] If the upper and lower sidebands adopt the same code sequence, namely C AP =C BP , the expression of TD-AltBOC modulating baseband signal is [0000] s ( t )=[ d A ( t ) c AD ( t )+ d B ( t ) c BD ( t )] SC B, cos ( t )+ j[−d A ( t ) c AD ( t )+ d B ( t ) c BD ( t )] SC B, sin ( t )+2 c BP ( t ) SC B, cos ( t ) [0049] Namely, in even time slot, there will only be binary cosine subcarrier on the same-phase branch. [0050] If the upper and lower sidebands adopt the reverse code sequence, namely C AP =−C BP , the expression of TD-AltBOC modulating baseband signal is [0000] s ( t )=[ d A ( t ) c AD ( t )+ d B ( t ) c BD ( t )] SC B, cos ( t )+ j[−d A ( t ) c AD ( t )+ d B ( t ) c BD ( t )] SC B, sin ( t )+2 jc BP ( t ) SC B, sin ( t ) [0051] Namely, in even time slot, there will only be binary sine subcarrier on the perpendicular branch. [0052] In order to reduce the complexity in signal reception and processing and optimize the receptivity, the invention adopts the TD-AltBOC programme with the same pseudo-code of pilot channel on the upper and lower sidebands. The mathematical representation is [0000] s ( t )=[ d A ( t ) c AD ( t )+ d B ( t ) c BD ( t )] SC B, cos ( t )+ j[−d A ( t ) c AD ( t )+ d B ( t ) c BD ( t )] SC B, sin ( t )+2 c P ( t ) SC B, cos ( t )   (1) [0053] When 2∫ x ·T c is an odd number, the normalized power spectrum of TD-AltBOC signal is [0000] G TD  -  AltBOC odd , +  ( f ) = R c ( π   f ) 2  cos 2  ( π   f R c )  sin 2  ( π   f 4   f s ) cos 2  ( π   f 2   f s )  ( 2 - cos  ( π   f 2   f s ) ) ( 2 ) [0054] When 2∫ x ·T c is an even number, the normalized power spectrum of TD-AltBOC signal is [0000] G TD  -  AltBOC even , +  ( f ) = R c ( π   f ) 2  sin 2  ( π   f R c )  sin 2  ( π   f 4   f s ) cos 2  ( π   f 2   f s )  ( 2 - cos  ( π   f 2   f s ) ) ( 3 ) [0055] II. Signal Generation Process [0056] FIG. 2 is an example of TD-AltBOC ( 15 , 10 ) signal generation of which the reference frequency f 0 =1.023 MHz; it contains the following procedures: [0057] The clock which is 4 times of the subcarrier frequency is taken as the clock signal CLK 0 for integrating control generated by TD-AltBOC baseband signal. [0058] 1) The control clock frequency is divided by 12 through the frequency divider 17 to generate the drive clock CLK 1 of pseudo-code generator. [0059] 2) The pseudo-code c BD of data channel of the upper sideband (+1 or −1), pseudo-code c AD of data channel of the lower sideband (+1 or −1) and the pseudo-code c P of pilot channel of the lower sideband (+1 or −1) are generated via half of the code rate Rc. [0060] 3) The binary NRZ waveform d A of the lower sideband data (1 refers to data bit 0; −1 refers to data bit 1) is multiplied by pseudo-code c AD of the data channel of the lower sideband through the multiplier 3 . [0061] 4) The binary NRZ waveform d B of the upper sideband data (1 refers to data bit 0; −1 refers to data bit 1) is multiplied by pseudo-code c BD of the data channel of the upper sideband through the multiplier 2. [0062] 5) After reverse sign of the output of multiplier 3 , it is added to the output of multiplier 2 through adder 4 (equivalent to subtracter). [0063] 6) The output of multiplier 3 is added to the output of multiplier 2 through adder 5 . [0064] 7) The pseudo-code output of pilot channel of the pseudo-code generator is multiplied by 2 through the multiplier 6 . [0065] 8) CLK 0 is used to drive subcarrier generator to generate binary sine subcarrier SC B, sin and binary cosine subcarrier SC B, cos . [0066] 9) The output of multiplier 6 is multiplied by binary cosine subcarrier SC B, cos through multiplier 9 to get the signal component of pilot channel at I branch; the signal component of pilot channel at Q branch is constantly 0. [0067] 10) The output of adder 5 is multiplied by binary cosine subcarrier SC B, cos through multiplier 8 to get the signal component of data channel at I branch. [0068] 11) The output of adder 4 is multiplied by binary sine subcarrier SC B, sin through multiplier 7 to get the signal component of data channel at Q branch. [0069] 12) The output of multiplier 7 and 0 are taken as the two inputs of time division multiplexer 11 . [0070] 13) The output of multiplier 8 and output of multiplier 9 are taken as the two inputs of time division multiplexer 12 . [0071] 14) Frequency of the baseband clock CLK 0 is divided by 6 through the frequency divider 18 to get the time division multiplexer control clock CLK 2 . [0072] 15) Under the control of clock CLK 2 , the time division multiplexer 11 and time division multiplexer 12 finish the synchronous switching of data channel and pilot channel; in the odd chip time slot, the time division multiplexer 11 outputs the signal component of data channel at Q branch, and time division multiplexer 12 outputs the signal component of data channel at I branch; in the even chip time slot, the time division multiplexer 11 outputs 0 , and time division multiplexer 12 outputs the signal component of pilot channel at I branch; The output of time division multiplexer 11 is the signal component of resultant signal at Q branch; the output of time division multiplexer 12 is the signal component of resultant signal at I branch. [0073] 16) Time division multiplexer 11 is used to output the modulated sine phase carrier of baseband signal at Q branch to get the component of radio-frequency signal at Q branch. [0074] 17) Time division multiplexer 12 is used to output the modulated cosine phase carrier of baseband signal at Q branch to get the component of radio-frequency signal at I branch. [0075] 18) The component of radio-frequency signal at Q branch and component of radio-frequency signal at I branch are integrated to get TD-AltBOC modulated radio frequency signal. [0076] In the example, the multipliers 13 and 14 and adder 15 constitute the RF modulator together. The invention is not limited to this form. It can also use a special QPSK modulator to realize radio frequency modulation; the number of frequency division of the frequency dividers 17 and 18 is also not restricted to the number of frequency division referred to in the example. When the subcarrier frequency and controlling parameters of code rate are changed, the number of frequency division of frequency dividers 17 and 18 shall also be changed. The number of frequency division of frequency divider 17 is 8*m/n, and the number of frequency division of frequency divider 18 is 4*m/n. [0077] III. A Preferred TD-AltBOC Implementation Plan [0078] As is shown in FIG. 3 , it includes the following procedures: [0079] 1) The baseband clock CLK 00 is used as the drive clock of TD-AltBOC modulation. [0080] 2) Frequency of clock CLK 00 is divided by 12 through frequency divider 24 to be the drive clock of pseudo-code generator. [0081] 3) The pseudo-code generator generates the pseudo-code c BD of data channel of the upper sideband and the pseudo-code c AD of data channel and pseudo-code cp of pilot channel of the lower sideband via half of the code rate Rc; different from the method shown in FIG. 2 , the value of pseudo-code sequence output in this method is selected as 0 or 1, which are respectively corresponding to 1 and −1 in the method shown in FIG. 2 . [0082] 4 ) The lower sideband data D A and pseudo-code c AD of data channel of the lower sideband are subject to exclusive-or operation with binary adder 20 to get the compound code C A of the data channel of the lower sideband. [0083] 5) The upper sideband data D B and pseudo-code c BD of data channel of the upper sideband are subject to exclusive-or operation with binary adder 21 to get the compound code C B of the data channel of the upper sideband. [0084] 6) The data channel compound code C A of lower sideband, data channel compound code C B of upper sideband and pseudo-code c P of pilot channel of upper sideband are taken as the input of table lookup unit 26 to search the corresponding amplitude sequence of I and Q component, and get the baseband wave form at I branch and baseband wave form at Q branch through pulse modulation. The table lookup unit 26 comprises the modulation mapping table comprising a lookup table at I branch and a lookup table at Q branch, which are shown in table 1 and table 2 respectively. [0085] 7) The baseband wave form at Q branch is used to modulate the sine phase carrier, and baseband wave form at I branch is used to modulate the cosine carrier wave to output TD-AltBOC modulating signal. [0000] TABLE 1 Lookup table for I branch Input Output (I) C A C B C P 1 2 3 4 5 6 7 8 9 10 11 12 0 0 0 1 −1 −1 1 1 −1 −1 1 1 −1 −1 1 0 0 1 1 −1 −1 1 1 −1 1 −1 −1 1 1 −1 0 1 0 0 0 0 0 0 0 −1 1 1 −1 −1 1 0 1 1 0 0 0 0 0 0 1 −1 −1 1 1 −1 1 0 0 0 0 0 0 0 0 −1 1 1 −1 −1 1 1 0 1 0 0 0 0 0 0 1 −1 −1 1 1 −1 1 1 0 −1 1 1 −1 −1 1 −1 1 1 −1 −1 1 1 1 1 −1 1 1 −1 −1 1 1 −1 −1 1 1 −1 [0000] TABLE 2 Lookup table for Q branch Input Output (Q) C A C B C P 1 2 3 4 5 6 7 8 9 10 11 12 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 1 0 −1 −1 1 1 −1 −1 0 0 0 0 0 0 0 1 1 −1 −1 1 1 −1 −1 0 0 0 0 0 0 1 0 0 1 1 −1 −1 1 1 0 0 0 0 0 0 1 0 1 1 1 −1 −1 1 1 0 0 0 0 0 0 1 1 0 0 0 0 0 0 0 0 0 0 0 0 0 1 1 1 0 0 0 0 0 0 0 0 0 0 0 0 [0086] Establishment of table 1 and table 2 is based on the subcarrier modulation theory in FIG. 2 , that is to say, all the possible C A , C B and C P values are combined, and each combination is subject to subcarrier modulation in the same way, thereby obtaining the baseband signal component at Q branch and at I branch corresponding to each combination; record each combination and its corresponding component at Q branch and at I branch to get the modulation mapping table. [0087] Table 1 and table 2 are established based on TD-AltBOC ( 15 , 10 ) modulation, and it is suitable when fs/Rc=1.5; under other circumstances, the tables can be established in the following way: [0088] (1) C A , C B , C P is mapped as C A ,C B ,C P according to the following rule: [0000] f  ( x ) = { 1 when   x = 0 - 1 when   x = 1   ↵ [0089] (2) When n takes 0, 1, . . . , 4fs/Rc−1, the output S j at I branch and output S Q at Q branch can be calculated according to the following formula [0000] S I  ( n ) = ( c A + c B ) × sign  ( cos  ( π 4 + n   π 2 ) ) S Q  ( n ) = ( c A + c B ) × sign  ( sin  ( π 4 + n   π 2 ) ) [0090] When n takes 4fs/Rc, . . . , 4fs/Rc−1, the output S I at I branch and output S Q at Q branch can be calculated according to the following formula [0000] S I  ( n ) = 2   c P × sign  ( cos  ( π 4 + n   π 2 ) ) S Q  ( n ) = 0.

The present invention provides a method for modulating a navigation signal, comprising: multiplying a data channel difference signal between upper and lower sidebands by a sine binary subcarrier to obtain an odd timeslot baseband signal of a branch Q, and multiplying a data channel sum signal of the upper and lower sidebands by a cosine binary subcarrier to obtain an odd timeslot baseband signal of a branch I of the data channel; multiplying a pilot channel difference signal between the upper and lower sidebands by the sine binary subcarrier to obtain an even timeslot baseband signal of the branch Q, and multiplying a pilot channel sum signal of the upper and lower sidebands by the cosine binary subcarrier to obtain an even timeslot baseband signal of the branch I; and performing QPSK modulation on the baseband signals of the branch I and branch Q to obtain a TD-AltBOC modulation signal. The present invention can implement transmission of different navigation services at two adjacent frequency bands, and each navigation service comprises a data channel and a pilot channel. The navigation signal of each sub-band may be received independently, or signals of the upper and lower sidebands may be jointly received to obtain high-precision navigation performance.

CROSS REFERENCE TO RELATED APPLICATIONS This application is a continuation-in-part of U.S. patent application Ser. No. 07/791,793, now U.S. Pat. No. 5,360,641 titled "Method and Apparatus for Detecting and Correcting Errors in Data on Magnetic Tape Media" filed Nov. 12, 1991. FIELD OF THE INVENTION This invention relates to magnetic data storage media and, in particular, to a method and apparatus for administering the data that are written on a magnetic tape media. PROBLEM It is a problem in the field of data storage systems to maximize the data storage capacity of the data storage medium while minimizing both the cost of the medium and the data retrieval time. Magnetic tape has become the industry standard data storage medium for the storage and retrieval of large amounts of data, where the media cost must be kept to a minimum and the data retrieval time is not a critical factor. The data storage capacity has been increased and media cost of magnetic tape have been reduced by the use of helical scan data recording techniques on magnetic tape media. Helical scan tape drive systems make use of the 3480-type magnetic tape cartridge which contains a single reel of half inch magnetic tape. The 3480-type magnetic tape cartridge is an industry standard media form factor used in the data processing industry for longitudinal recording of data on magnetic tape. The selection of this form factor is desirable due to the fact that automated library systems, such as the 4400 Automated Cartridge System (ACS) manufactured by Storage Technology Corporation of Louisville, Colorado, are presently used to robotically store and retrieve a large number of 3480-type magnetic tape cartridges for an associated plurality of tape drives. The helical scan data recording format enables the user to store significantly more data on a 3480-type form factor magnetic tape cartridge than is presently available with longitudinal recording on magnetic tape. A significant problem with all magnetic tape media is that a significant segment of the data retrieval time represents the mechanical positioning of the magnetic tape on the associated tape drive to locate a specific data record or end of data to enable the associated host computer to begin reading a data record or writing new data records on the magnetic tape. Furthermore, these tape drive systems rely on the host computer to administer the data that are stored on the magnetic tape. The administration includes retaining error logs, user related administrative information, identification of the write protect status of the data, physical location of the data on the magnetic tape, etc. Much other relevant media administrative data (such as identification of the manufacturer of the magnetic tape, a record of the read/write history of the magnetic tape, etc.) is presently unavailable in data processing systems. The administrative data presently used are host computer dependent, being stored in the memory of the host computer. There presently exists no capability to administer the data on the magnetic tape itself when moved from one host computer system to another. The integrity of the administrative information that relates to the data record stored on the magnetic tape is therefore dependent on the magnetic tape being read and written only by a single host computer. This is an impractical limitation in many environments and there presently does not exist any mechanism for reliably administering the data records that are written on to a mountable magnetic tape medium. SOLUTION The above described problems are solved and a technical advance achieved in the field by the method and apparatus of the present invention for administering data on a magnetic tape medium to make the magnetic tape self-defining. This is accomplished by the use of control software and hardware in the tape drive control unit that creates and manages a header segment at the beginning of the magnetic tape. This header is interposed between a leader portion of the magnetic tape on the 3480-type cartridge and the remainder of the magnetic tape contained therein. This header segment contains two sections, a first of which is a data record directory that is used by the control unit to denote the location of data records written on to the magnetic tape as well as administrative information associated with the data record. The second section of the header is an administrative information section that contains data relating to the magnetic tape itself. The administrative information includes the identification of the tape drive, write protect status of the magnetic tape, identification of the medium, error record log and other information that enables the user, the host processor and the tape drive control unit to manage the data record written onto the magnetic tape without reference to any other sources of administrative data. In addition, the header itself can be self protected by computing a error correction code across the data contained within the header to enable the control unit to identify whether the header integrity has been compromised. To simplify the task of locating a data record, search segments, consisting of a predetermined number of scan groups, are used. Whenever the magnetic tape cartridge is mounted on a tape drive and the magnetic tape contained therein threaded through the tape threading path onto the tape drive takeup reel, the tape drive control unit accesses the header segment of the magnetic tape to read the administrative data written thereon. If the host processor has requested a locate data record operation, the identity of the requested data record is used to scan the data record directory section of the header segment to locate the directory entry relating to the search segment of the requested data record. Once this directory entry for the requested data record has been located, the control unit can use the information, contained within this directory entry, indicative of the physical position of the requested data record on the magnetic tape. This physical positioning information consisting of a physical scan group count, can then be used by the tape drive to quickly and precisely position the beginning of this data record under the read/write heads of the tape drive. The use of this positioning information reduces the tape positioning time, thereby improving the data retrieval time of the tape drive system. The positioning information is indicative of the physical location of the data record on the magnetic tape and the magnetic tape typically includes positioning information written into at least one of the longitudinal tracks contained on the helical scan magnetic tape. This same positioning information is available to locate the end of any data record written on the magnetic tape to enable the tape drive to write the next successive data record following the physical end of the last previously written data record. Data records can also be written in varying formats on the magnetic tape since the administrative information contained in the header segment enables the associated control unit to physically locate the data record and identify its format and extent independent of the associated host processor. In prior magnetic tape systems, a fixed block architecture is typically used in order to enable the host processor to manage the magnetic tape, since the magnetic tape was divided into a plurality of fixed size segments. This uniformity enabled the host processor to read and write data records on any magnetic tape since the format of the magnetic tape was consistent. With the availability of administrative information contained in a header segment, both fixed block and variable length data records can be written on to the magnetic tape independent of the host processor since the magnetic tape is self defining. The second section of the header segment includes administrative information relating to the read/write history of the data records, error logs to note the physical integrity of the magnetic tape, identification of the manufacturer of the magnetic tape, write protect status of the magnetic tape, magnetic tape volume serial number, any magnetic tape. This administrative data enable the control unit and the host additional information relating to the administration of the data records stored on the processor to identify a magnetic tape that is subject to an unacceptable level of errors on the medium. Such a magnetic tape can then be retired and the data contained thereon rewritten to a new tape before the integrity of this data is compromised. In addition, the error logs contain data that can be used to detect tape drive failures since a record of the errors and corresponding tape drives is maintained in the header. Therefore, the method and apparatus of the present invention enable the magnetic tape to be self defining by the use of a header segment located at the beginning of the magnetic tape. The self defining capability enables the magnetic tape to be used by any host processor and provides additional features and capabilities heretofore unavailable on magnetic tape media. BRIEF DESCRIPTION OF THE DRAWING FIG. 1 illustrates the physical format of the magnetic tape medium; FIG. 2 illustrates the data recording format of helical scan magnetic tape; FIG. 3 illustrates in block diagram form the overall architecture of a typical tape drive control unit; FIG. 4 illustrates in block diagram form the elements used to create and update the header segment of the magnetic tape; FIG. 5 illustrates the elements contained in the header segment of the magnetic tape; FIG. 6 illustrates the elements contained in the directory section of the header segment of the magnetic tape; FIG. 7 illustrates additional detail of the data recording format of the helical scan magnetic tape; FIG. 8 illustrates in block diagram form the architecture of the write data path in the tape drive control unit; FIG. 9 illustrates the positioning information recorded on the magnetic tape; FIG. 10 illustrates the elements contained in the administrative section of the header segment of the magnetic tape; FIGS. 11-13 illustrate in flow diagram form the operational steps taken by the control unit to perform a number of operations on the magnetic tape; and FIGS. 14-16 illustrates various aspects of the data formats. DETAILED DESCRIPTION Tape Drive System Architecture The apparatus illustrated in FIG. 3 represents the well known tape transport elements found in helical scan tape drive subsystems 300 that are used to read and write data on magnetic tape 100. The magnetic tape 100 is wound on a single reel 110 which rotates around spindle 111 within magnetic tape cartridge 301. In a helical scan tape drive subsystem 300, magnetic tape 100 from magnetic tape cartridge 301 is threaded in direction A past a fixed full width erase head 310, scanner 320 (which contains two pairs of helical read heads 322 and two pairs of helical write heads 321 and one pair of erase heads 323), a fixed longitudinal erase head 331 and a fixed longitudinal read/write head 332. The magnetic tape 100 then passes around guide 340, over capstan 341 to be wound on machine reel 360 which rotates around spindle 361. The full width erase head 310 erases the entire width of magnetic tape 100 and is used when data is recorded on virgin tape. It is also used when data are recorded on a previously used magnetic tape, if none of the data previously recorded on magnetic tape 100 is to be preserved. Host processor 1 transmits a stream of data records to control unit 350 in tape drive subsystem 300, where the data records are formatted for writing in helical scan form on magnetic tape 100 via scanner 320. The tape wrap angle around scanner 320 is slightly greater than 180 so that a pair of read heads 322, a pair of write heads 321 and one erase head 323 are constantly in contact with magnetic tape 100 in order to continuously read and write data thereon. The helical write head pairs 321 simultaneously record two tracks of data at a time on magnetic tape 100 with an azimuth angle between adjacent tracks being approximately plus and minus 20. Similarly, helical read head pairs 322 simultaneously play back two tracks of data at a time from magnetic tape 100. There are also three fixed longitudinal erase 331 and read/write heads 332 to read and write data on the corresponding three longitudinal tracks contained on magnetic tape 100: control, time code and one to be determined. These three longitudinal read/write heads 332 can be used individually or in any combination when editing new information into pre-recorded data. Physical Format of Helical Scan Magnetic Tape FIG. 1 illustrates the physical format of the helical scan magnetic tape 100, including the header (ILH) segment 105 thereof (also termed internal leader header). The magnetic tape 100 includes a leader block 101 that is attached at one end thereto and a single reel 110 around which magnetic tape 100 is wound into cartridge 301. A length of leader 103 is interposed between the leader block 101 and the density identification segment 104 of magnetic tape 100. The leader section 103 includes a beginning of tape hole 102 which provides an indication to the tape drive subsystem 300 that the one end of the magnetic tape 100 is reached. The density identification segment 104 typically consists of 256 scan groups 700 (FIG. 7) written on magnetic tape 100. The density identification segment 104 represents data, for tape drive control unit 350 to access, indicative of the format of the data recorded on magnetic tape 100. Internal leader header segment 105 is located at the end of density identification segment 104 of magnetic tape 100. The internal leader header 105 consists of a three scan groups 700, the third of Which is an ECC scan group to error check the two preceding internal leader header scan groups. The internal leader header 105 is followed by separator segment 106 of magnetic tape 100, which typically consists of 125 scan groups. The separator segment 106 isolates the logical beginning of tape (BOT) 123, which is the start of the data area 107 of magnetic tape 100, from the prepended header information described above. The data area 107 of magnetic tape 100 constitutes the majority of magnetic tape 100 and ends at physical end of tape 125 which is a predetermined distance from tape to hub junction 126, wherein magnetic tape 100 is affixed to single reel 110 of magnetic tape cartridge 301. A length of trailer tape 109 may be interposed between the physical end of tape 125 and tape to hub junction 126. This serves as a method of wrapping magnetic tape 100 around the reel 110 in order to provide a method of attachment thereto and also includes an end of tape hole 124 which indicates to tape drive subsystem 300 that an end of the magnetic tape 100 has been reached. Internal Leader Header The internal leader header 105 consists of administrative information which typically includes: Data Record Directory Logical block locations Administrative Information Location of last Data Scan group written Number of volume loads Number of read/write errors for the last n mounts Serial number of last m drives upon which this cartridge was mounted Volume ID Time and date stamp of mount Tape type and length Safe File information Manufacturer's ID and Production Batch Numbers The internal leader header segment 105 of magnetic tape 100 is read on every load of magnetic tape cartridge 301 into a tape drive subsystem 300. The internal leader header segment 105 is updated by magnetic tape drive subsystem 300 prior to magnetic tape 100 being physically unloaded therefrom in order to update the header information concerning read and write information contained therein. The internal leader header 105 illustrated in FIG. 5 includes two segments: administrative information 501, and data record search directory 502. The data record search directory 502 includes a plurality of entries (502-1 to 502-n), one for each search segment boundary that are crossed. In addition, the data that are recorded on magnetic tape 100 are divided into super groups, each of which comprise up to 24 scan groups of data with an appended ECC scan group. These super groups of data are written on to the magnetic tape 100 via the search segments, with super groups of data, due to their variable size, and not necessarily beginning at a search segment boundary. The search segments are 32 scan groups in length. Thus, the location of a particular data record can be determined from the physical scan group count of the start of the super group. Data Record Directory Each directory entry 502-* includes the information illustrated in FIG. 6 and written by the apparatus illustrated in FIG. 4. In fact, the apparatus of FIG. 4 can be software elements located in tape drive control unit 350 used to create a scan group 700 and control unit 350 can count the total number of scan groups, for internal leader header 105. The first element in the entry is a physical scan group count 601 of four bytes length stored in element 2602 which represents a unique physical location on magnetic tape 100. Since each search segment contains a fixed number of scan groups 700 written on to magnetic tape 100, the location of a specific scan group within the selected search segment is a simple process of positioning the magnetic tape 100 a calculated distance from the beginning of tape point. The second element contained in the entry is a file identification number 602 of three bytes created by element 2603 and which identifies a numerical file in which scan group 700 is contained. The file identification 602 is used internally in tape drive subsystem 300. The file identification 602 is also termed file marks or tape marks and are sent from host processor 1, and they are used to separate data. This file ID number 602 provides a scan group to file correspondence in order to simplify the administering of the data within files on magnetic tape 100. The third element contained in the entry is a logical block number of first starting host processor data packet within a super group 603, which is a five byte long field created by element 2601. This block number identifies the first data group of a super group that follows the search segment boundary. The final element in the entry is a reserved field 604 of twenty bytes for future use as to be determined for future elements 2604 such as a data record specific write protect bit. Administrative Information FIG. 10 illustrates the information typically contained in the administration information section 501 of internal leader header 105. A first segment of information contained in internal leader header 105 is the volume identification 1001 which consists of 80 bytes created by element 2101 that represent the volume identification number assigned to magnetic tape cartridge 301. A second section of administrative information 501 is the tape type and length, which is a one byte long field created by element 2102 to indicate the type of medium and its length. A third segment 1003 of administrative information created by element 2103 is the tape manufacturer's identification and production batch number, which consists of 128 bytes of information, to provide the user with information concerning the date of manufacture of this medium as well as the identification of the manufacturer and their particular production batch number. This information assists the user in identifying media that has been recalled by the manufacturer or media of a certain class that is more prone to errors than other similar types of media. Further entries that can be included in administration information 501 are tape usage statistics 1004 created by element 2104 indicative of the number of times that magnetic tape cartridge 301 has been loaded on tape drive subsystem 300 and the number of read and write cycles magnetic tape 100has been subject to. These usage statistics can include the serial number of tape drive subsystem 300, as well as date and time stamps to record load including the initial use date. Another entry 1005 is a recording type byte created by element 2105 to indicate write-without-Retry or a write protect file safe status bit for magnetic tape 100. Further information includes error data 1007 created by element 2107, including a record of the number of read/write errors detected and corrected in the last n times the magnetic tape is mounted on a tape drive as well as the identification of the tape drives upon which this magnetic tape was mounted. The error data 1007 include a collection of all the error statistics that are produced during the last n mounts in order to enable host processor 1 to access this information in order to determine whether magnetic tape 100 is flawed or whether the associated tape drive subsystem 300 on which is was mounted is experiencing regular failures. Finally, additional memory is provided for future use to enable magnetic tape 100 to store predefined information, either selected by the user or defined by the tape drive manufacturer. Data Format of the Helical Scan Magnetic Tape FIGS. 2 and 7 illustrate the data recording format of helical scan magnetic tape 100 used herein. The scan group 700 is the basic unit for formatting data on magnetic tape 100. As two adjacent write heads 321 of scanner 320 move across magnetic tape 100, two helical tracks 204 of data are simultaneously written on to magnetic tape 100. Once scanner 320 has completed one half of a revolution, the other pair of write heads 321 begins to write the next two adjacent tracks 204 on to magnetic tape 100. One and a half revolutions of scanner 320 produce the six tracks (1-6) illustrated in FIG. 7 to complete a single scan group 700. As can be seen from FIG. 7, a postamble 703 and preamble 701 are written on either end of the data area 702 of each track 204 written on to magnetic tape 100 in order to enable read heads 322 to accurately read the data contained therein. In addition, the data format of a single helical track is illustrated in FIG. 7 to note that preamble data begin a track on magnetic tape 100 and postamble data end a track on magnetic tape 100. Interposed between preamble 712 and postamble 713 are 408 sync blocks 711, each of which contain eighty-five bytes of user data 723. In addition, two synchronization bytes 721 are prepended to data 723 along with two identification bytes 722. Eight bytes of inner error correcting code 724 are appended to the end of data 723 in order to complete the format of sync block 711. The inner ECC code 724 illustrated in FIG. 7 covers both data 723 and identification 722 but not synchronization bytes 721 contained in sync block 711. Therefore, a 95, 87 Reed Solomon code is formed to detect errors contained in data 723 and identification 722 fields of sync block 711. The sync pattern 721 portion of sync block 711 is a fixed pattern of data bits used to resynchronize the read clock and logic after dropouts. Of the 408 sync blocks 711 in a single track 204, twenty-four are used at the start of track 204 for outer ECC check bytes (described below). Therefore, there are (408-24)×85=32,640 bytes per track 24 of user data 723. With six tracks 204 per scan group 700, a scan group 700 therefore contains 195,840 bytes of user data 723. FIG. 9 illustrates the positioning information recorded on the magnetic tape 100. The basic unit used to transfer data from the host processor 1 to magnetic tape 100 is the data block 901, which is analogous to a conventional data record. Each data block 901 sent by the host processor 1 to be written to magnetic tape 100 is sequentially assigned a unique block number by the tape drive control unit 350. Data blocks 901 are logical entities which may have different lengths, unlike fixed length blocks which are required by some prior art magnetic recording systems. A data block 901 may be larger than a physical scan group 700, and may also span two or more adjacent scan groups 700. Since each physical scan group 700 is the same size, the variable size of the data blocks 901 is transparent to the tape drive control unit 350 when a high speed data block search is conducted using the longitudinal track servo information in conjunction with the scan group location in the internal leader header 105. Data block IDs are noted for each search segment in the internal leader header 105 in order to provide a mechanism for increasing the speed of a search, and for verifying the location of the contiguously stored data block 901. These data block IDs are referred to as "host block IDs" since the data block 901 is the basic unit used by the host processor 1 to write data to magnetic tape 100. Scan group 904 boundaries are locatable via the servo control track 202 at a 60× or 100× search speed. Furthermore, the placement of block IDs in scan group headers provides a verification of the correctness of a search to a particular search segment 904 wherein a block having a predetermined (expected) ID is expected to be found. The scan group header included in the scan group 700 typically includes the following information: ______________________________________1. Type of scan group 1 byte2. Logical scan group number 4 bytes3. Beginning host block ID 5 bytes (Block ID of byte 0)4. Ending host block ID 5 bytes (Block ID of last byte)5. File ID number 3 bytes6. Number of pad bytes in 3 bytes logical scan group7. Information data byte: >--> 1 byte File safe bit Write-without-retry bit8. Continuation Information: >--> 1 byte First host block continued from previous scan group bit Ending host block continues into next scan group bit9. Scan group CRC 2 bytes10. Scan group header CRC (fixed) 2 bytes11. Pointer to first packet that 3 bytes begins in this scan group12. Variable Information: Physical Scan Group Count 4 bytes rewrite Count 1 byte Variable CRC 2 bytes13. If an ECC group, the number 1 byte of data groups covered by this ECC. If a data group, the sequence number within this ECC super-group.14. Miscellaneous information 18 bytes SUB TOTAL 56 RESERVED 72 TOTAL 128______________________________________ Longitudinal Tracks The tape format for helical scan recorded magnetic tape 100 includes three longitudinal tracks 201-203 written on magnetic tape 100: servo control track 202, time code track 201 and one track 203, the use of which is to be determined. The servo control 202 and time code 201 tracks are located at the bottom of magnetic tape 100 while the unused track 203 is located at the top of magnetic tape 100. The servo control track 202 is recorded as helical tracks 204 are written onto magnetic tape 100 and contains pulse edges that mark the location of each helical track pair written on to magnetic tape 100. One use of servo control track 202 is to synchronize, during playback, the rotation of scanner 320 with the position of helical tracks 204 on magnetic tape 100. The time code track 201 is recorded as helical tracks 204 are written on to magnetic tape 100. The time code track 201 contains location information that uniquely identifies each scan group pair 700 on magnetic tape 100. Similar location information is contained in the helical tracks 204 themselves, but the longitudinal time code track 201 can be read at a higher tape speed, i.e., at 60× normal recording speed. This information can be used to position magnetic tape 100, while being transported at a 60× or 100× normal recording speed, to a specified scan group 700, based on scan group location information contained in the data record directory section 502 of internal leader header 105. The various high speed search operations of the present invention are used to position a particular physical location on magnetic tape 100 under the read/write heads 321, 322 of scanner 320 in a significantly faster time and to a more accurate location than prior art methods. These prior art methods include positioning the tape to an approximate location of a desired data block, or, less efficiently, searching for the desired data block by performing a continuous read operation until the data block is located. The servo system in a typical tape drive such as that used by the present method is capable of performing a high speed search to a scan group 700 which can be located via time code track 201 on magnetic tape 100. The servo can locate a particular area consisting of a group of twelve helical tracks 204 or two scan groups 700. By using longitudinal time code track 201, tape drive subsystem 300 can perform a high speed search at 60× or 100× normal recording speed to within two scan groups containing the data record that is requested. This is a much finer resolution than can be obtained by using a simple but less accurate distance measurement employed by prior art physical data identification techniques. Write Data Path FIG. 8 illustrates in block diagram form the architecture of the write data path contained within tape drive control unit 350 while FIGS. 14-16 illustrate data formats used therein. The write data path includes a channel interface circuit 801 which interconnects tape drive control unit 350 with data channel 2 from host processor 1. Channel interface circuit 801 receives data blocks from host processor 1 and stores them in buffer 802 for processing by the hardware and software contained in tape drive control unit 350. Buffer 802 stores a predetermined amount of data that is received from host processor 1. A typical buffer size is 16 Mb or greater in order that host processor 1 can write a significant amount of data into tape drive control unit 350 without requiring interruption of the data transfer caused by the movement or delay in movement of the magnetic tape 100 on tape drive 300. Packetizer circuit 802 receives data from channel interface 801 and packetizes the data 1401 as shown in FIG. 14 by adding a packet header 1402 which is protected by a cyclic redundancy check (CRC) (not shown). Data records received from host processor 1, whose block size do not exceed 262K bytes, are followed by a packet trailer 1403 and a CRC (not shown) which protects both data 1401 and packet trailer 1403. The packets 1400 produced by packetizer 803 are transmitted to buffer 803 for use by scan group generator 804 which reformats the packetized data 1400 by concatenating them into scan groups 1500 as shown in FIG. 15. If a scan group data field is incomplete, pad bytes are added to the scan group data field 1503 as required to complete the scan group data field 1503. A fixed scan group header 1501 and a two byte CRC character 1502 are then prepended to the scan group data field 1503 and a CRC code 1504 also appended thereto. The partial scan group 1500 thus generated is transmitted to third level ECC generator 805 which Exclusive ORs (for example) twenty-four scan groups 1500 to produce a third level ECC scan group. In addition, the scan groups 1500 are concurrently transmitted to variable scan group header generator 806 which produces, as shown in FIG. 16, a variable scan group header 1601 and CRC code 1602 which protects this rewriteable scan group header 1601, both of which are prepended to the scan group 1500. The resultant data 1600 is then transmitted to the channel write circuits 807 for writing the data in helical scan format on to magnetic tape 100. Tape Read Operations The search segment is used to make search entries in the header. The size of the search segment is a predetermined number of scan groups, typically 32 scan groups. The count indicative of the position of the first data group of a super group within a particular search segment is entered into the directory. In reading a data record from the magnetic tape, the first data group of this data record may occur earlier or later on the magnetic tape than the location identified in the directory. The actual location of the start of the data record can legitimately be later due to write skips as disclosed herein, since a later version of this scan group may be the one that is to be read. However, the scan group should not occur earlier on the magnetic tape or later than a reasonable number of scan groups unless the directory entry is invalid. When an entry in the directory is found to be invalid, then the integrity of the entire directory is in question and the directory is considered invalid in its entirety. Data Record Write to Magnetic Tape FIGS. 11-13 illustrate in flow diagram form the operational steps taken by tape drive 300 to write data in helical scan form on magnetic tape 100. At step 1101, a magnetic tape cartridge 301 is inserted into tape drive 300 and the tape drive mechanism illustrated in FIG. 3 loads the magnetic tape 100 by threading the leader block 101 and magnetic tape 100 through the tape threading path to the takeup reel 360 which rotates around spindle 361. At step 1102, magnetic tape 100 is advanced forward in order to enable the tape drive control unit 350 to read the internal leader header 105 written on to this magnetic tape 100 via read heads 322 of scanner 320. If this tape is a blank tape, there is no internal leader header 105 on this magnetic tape 100 and the header segment is created thereon. If the tape has been previously used, the internal leader header 105 contains the information described above and enables tape drive control unit 350 to determine where on magnetic tape 100 the data records have been written. At step 1103, tape drive control unit 350 presents a ready signal to host processor 1 indicating that tape drive subsystem 300 is ready to receive data and commands from host computer 1 via data channel 2. At step 1104, host processor 1 transmits data over data channel 2 that interconnects it to tape drive 300 and the data is written into buffer 803. As the data are written into buffer 803, tape drive control unit 350 checks for errors to make sure there are no transmission errors in the data received from host processor 1. Since tape drive subsystem 300 can typically write data to magnetic tape 100 faster than host processor 1 can write the data into buffer 803, tape drive control unit 350 waits at step 1105 for host processor 1 to complete its data transmission and checks for errors. At step 1106 tape drive subsystem 300 presents the proper ending status to host processor 1 indicating that the data records have been written into buffer 803. When buffer 803 is filled to a predetermined level, tape drive subsystem 300 begins writing the data to magnetic tape 100 in order to free up more buffer space for host processor 1 to continue writing data records therein. At step 1107 tape drive control unit 350 ensures that scanner 320, magnetic tape 100 and servos (not shown) are all synchronized. At step 1108, the control unit 350 positions magnetic tape 100 to the physical location on magnetic tape 100 where writing is to begin. At step 1109, control unit 350 prepares the appropriate scan group 700 to be written. For the purpose of this description, assume that the scan groups written to magnetic tape 100 represent data records received from host processor 1 and stored in buffer 803. As described above, third level ECC scan groups are periodically written into the stream of data records to form super groups which are written on magnetic tape 100. At step 1110, control unit 350 activates the read/write mechanism described above to write the scan group to magnetic tape 100 and at step 1111, the read after write process reads scan groups 700 as they are written on to magnetic tape 100 in order to ensure their integrity. If an error is detected in the written scan group, the scan group is rewritten further along magnetic tape 100 at step 1116. At step 1112, control unit 350 checks the buffer status and at step 1113 determines whether further data is in buffer 803. If data are in buffer 803, steps 1109-1113 are repeated until, at step 1113, no more data is available from buffer 803. Control unit 350 determines at step 1114 whether more data are expected from host processor 1. At this point (step 1117), control unit 350 writes a plurality (typically four) pad groups and end groups after the last written scan group in order to complete the writing of this stream of data records. At step 1118, magnetic tape 100 is rewound to its beginning and, at step 1119, data record directory 502 is updated with information concerning the physical location and identity of the data records that have just been written on to magnetic tape 100. At step 1120, control unit 350 updates the administrative information section 501 of internal leader header 105. This information is described above and entails elements 2601-2604 and 2101-2108 being sequentially activated and their outputs multiplexed by Multiplexer 2201 into buffer 802 to form a scan group for internal leader header 105. The elements disclosed in FIG. 4 can be registers in control unit 350, software routines that execute in control unit 350, memory entries in the memory (not shown) that is part of control unit 350, etc. Suffice it to say that the nature of the data created by each of elements 2601-2604, 2101-2108 determines the implementation of the corresponding element. Multiplexer 2201 represents the element in control unit 350 that formats all the data created by elements 2601-2608, 2101-2108 into the formats illustrated in FIGS. 6 and 10. Again, it is expected that Multiplexer 2201 may be a software element within control unit 350 that formats the data created by elements 2601-2608, 2101-2108 into data record-directory 502 and administrative information 501 sections of internal leader header. Thus, on an initial load of magnetic tape 100, the internal leader header 105 is read and the data contained therein are read into elements 2601-2608, 2101-2108 as illustrated by the inputs on the left side of FIG. 4 to each of the elements 2601-2608, 2101-2108. During the use of magnetic tape 100, many of these data entries are updated, supplemented and/or modified until control unit 350 rewrites internal leader header 105, at which time the data contained in and generated by elements 2601-2608, 2101-2108 is used to populate internal leader header 105, which is then written on magnetic tape 100 at step 1121. At step 1122, the tape write operation is completed and magnetic tape 100 can be unloaded or positioned ready for subsequent data record writes. If, at step 1114, control unit 350 determines that further data are expected from host processor 1, control unit 350 at step 1115 writes a plurality of pad scan groups following the end of the last written data scan group and rewinds magnetic tape 100 to the end of the first of these pad scan groups. Control unit 350 then returns to step 1103 and presents a ready status to host processor 1.

The control software and hardware in the tape drive control unit creates and manages a header segment at the beginning of the magnetic tape. This header is interposed between a leader portion of the magnetic tape on the 3480-type cartridge and the remainder of the magnetic tape contained therein. This header segment contains two sections, a first of which is a data record directory that is used by the control unit to denote the location of each data record written on to the magnetic tape as well as administrative information associated with the data record. The second section of the header is an administrative information section that contains data relating to the magnetic tape itself. The administrative information includes the identification of the tape volume, the tape drive, write protect status of the magnetic tape, identification of the media, error record log and other information that enables the user, the host processor and the tape drive control unit to manage the data records written onto the magnetic tape without reference to any other sources of administrative data. In addition, the header itself can be self protected by computing an error correction code across the data contained within the header to enable the control unit to identify whether the header integrity has been compromised.

BACKGROUND Great progress has been made in radiotherapy and radiosurgery recently in dosage planning. People are striving to move treatment more and more in the direction of radiosurgery, i.e. working with high radiation dosages applied in a few, and preferably in just a single, radiation treatment to a target volume, so for example to a tumour. Although dosage planning is, as mentioned, relatively successful, the use of high doses administered in a few or a single fraction is often obstructed by the fact that the patient and/or the body section to be irradiated can be positioned only relatively imprecisely. In order to avoid significant damage to healthy tissue, one therefore falls back in most cases on conventional fractionated radiotherapy, in which repeated irradiation with small doses is applied. In order to improve positioning, one is currently still making do with a very imprecise “manual” method, whereby an x-ray image of a body section of the patient is produced on the linear accelerator. This image is compared with a reference x-ray image previously taken on the simulator (an x-ray device with an identical geometry to the linear accelerator). The doctor carrying out the treatment then compares the x-ray image and the simulator image, for example on a viewing box, thereby determining the positioning error between the actual position of the patient and the desired position using a ruler and then shifting the patient accordingly. At best, a centre-beam cross and/or the contour of the outer field boundary in both images are also available to the doctor as a starting point. The field boundaries may be defined by lead blocks or mobile radiation screens, respectively. Even when comparing with DRRs (“simulator images” virtually determined from a three-dimensional image data set) instead of with actual simulator images, this method does not change. Disadvantageously, this way of positioning the patient is imprecise, for the following reasons alone: The images are projective, and therefore not to original scale. (No uniform image scale exists). The “manual” reading of the required shift is imprecise. A three-dimensional spatial shift from two-dimensional images and without computer assistance is only possible to a limited extent, and requires a very experienced user. An iterative method for aligning therapy radiation with a treatment target is known from U.S. Pat. No. 5,901,199, wherein diagnostic computer tomography data are used, with the aid of which a multitude of reconstructed x-ray images, so-called DRRs (Digitally Reconstructed Radiographs), are generated. These DRRs are repeatedly produced and compared with a x-ray image taken at the source, until one is found which shows a sufficient correspondence. With the aid of the data thus obtained, the position of the treatment device and/or of the beam used for treatment is corrected such that the beam hits the treatment target. A disadvantage of this method is the high computational demands, since such DRRs initially have to be generated at random, and a great many DRRs have to be compared with the actual x-ray image. In particular, an “intelligent” algorithm needs to be found in order to approach the matching DRR for each body section and for each patient in turn in a reasonable period of time. Furthermore, a method is known in principle for producing x-ray images at the source in a treatment room, in order to integrate the up-to-date information thus gained about the position of the treatment target and its surroundings into the course of the treatment, whereby two securely assembled x-ray sources are regularly used laterally above the patient in radiation treatment, as well as two securely installed image recorders, e.g. let into the floor of the treatment room, with a separate image recorder for each x-ray source. These systems are inflexible and costly in terms of apparatus, and therefore also expensive. SUMMARY OF THE INVENTION It is the object of the present invention to propose a method and a device for accurately positioning a patient for radiotherapy and/or radiosurgery, wherein the above disadvantages of the prior art are not present. In particular, a greater flexibility in producing images and a cost-effective system are to be made available. This object is solved in accordance with the invention by a method for accurately positioning a patient for radiotherapy and/or radiosurgery, comprising the following steps: a) the patient is pre-positioned as accurately as possible with respect to a linear accelerator; b) at least two x-ray images of the patient and/or one of the parts of his body in the vicinity of the radiation target point are produced from different respective recording angles on a single image recorder; c) the x-ray image is spatially localised; d) at least one reconstructed image, corresponding to each x-ray image, especially isocentrically, and deriving from a three-dimensional patient scan data set, is produced; e) the reconstructed image and the x-ray images are superimposed, and the positioning error is determined electronically and/or with computer guidance by way of particular landmarks, the intensity gradient or the contours in the two images; and f) the position of the patient is corrected by way of the determined positioning error. The advantageous nature of the present invention is based, among other things, upon the fact that the x-ray images are produced on a single image recorder. Through this, the overall construction is naturally more cost-effective, and gains above all in flexibility, because a single image recorder can much more easily be placed right where it is most effective. In particular, it can also be provided mobile, which opens additional possibilities in recording technology for the overall method. Furthermore, repositioning as proposed in accordance with the invention offers a very quick and simple way of achieving very accurate target irradiation. Determining the positioning error electronically and/or with computer guidance considerably increases accuracy as compared to manual methods. Spatially localising the x-ray image allows even this input value to be evaluated with sufficient accuracy, such that errors and delays in repositioning may also be avoided from this side. In a preferred embodiment of the method in accordance with the invention, the x-ray images are produced in positions defined offset with respect to the pre-positioning, outside of the radiation range of the linear accelerator, the reconstructed images being produced with the same offset. Positioning of the image recorder for the x-ray images absolutely outside the primary beam of the linear accelerator can thus be achieved. While correcting the position of the patient, the defined offset is then compensated for, together with the positioning error. Within the framework of the method in accordance with the invention, there exists the possibility of producing the x-ray images at an oblique angle on an image recorder spatially arranged horizontally, and of projecting them back onto each respectively defined normal plane, the corresponding reconstructed images being likewise produced in these normal planes. Such images in the normal plane do not suffer from distortions, and are therefore easier to interpret visually. In a method in accordance with the invention, the patient is pre-positioned by means of a navigation and tracking system with computer and camera guidance, with the aid of artificial, in particular reflecting, arrangements of markers on the patient and on the devices for treatment. In carrying out the method in accordance with the invention, such a navigation and tracking system can assume all necessary position determination and output corresponding information, for example to a computer display unit. The patient can, however, also be pre-positioned using markings on the patient's skin, natural landmarks or laser markings. The x-ray images and the reconstructed images can in accordance with the invention be superimposed by way of natural structures present in the x-ray images and the reconstructed images, in particular bone structures. On the other hand, or in combination therewith, the x-ray images and the reconstructed images can be superimposed by way of artificial structures present in the x-ray images and the reconstructed images, in particular by way of implanted markers, preferably gold spheres. In an embodiment of the method in accordance with the invention, the x-ray images and the reconstructed images are superimposed by marking and sliding over one another on a computer display unit by the operator (e.g. using a mouse, keyboard, touch screen, joystick, etc.). On the other hand, the x-ray images and the reconstructed images can also be superimposed by automatic, computer-guided image fusion. In preferred embodiments of the method in accordance with the invention, the reconstructed image/s is/are produced as: Digitally Reconstructed Radiographs (DRRs); Digitally Composited Radiographs (DCRs); MIP images. or as any two-dimensional image reconstruction from a three-dimensional patient scan data set. The position of the patient can be altered by shifting the patient table, in particular while correcting the positioning error, but also during any other alterations to the position, and in particular can be automatically guided and corrected by a navigation and tracking system with computer and camera guidance, using markers on the patient and on the patient table. Naturally, the position of the patient may also be corrected by manually guiding the table. In accordance with an advantageous embodiment of the method in accordance with the invention, a multitude of images over a breathing cycle are produced from each angle, each time x-ray image are produced from the different recording angles, the breath-dependent movement of the markings arranged on the patient or in the vicinity of the radiation target being tracked by a navigation and tracking system with computer and camera guidance and referenced with the dynamic shifting of the target point directly or indirectly (e.g. via implanted markers) visible in the images. The breath-dependent movement of the radiation target is reckoned back, in order to enable breath compensation during irradiation. The invention further relates to a device for accurately positioning a patient for radiotherapy and/or radiosurgery, comprising: a) at least two x-ray sources with which x-ray images of the patient and/or one of the parts of his body in the vicinity of the radiation target point may be produced from different recording angles; b) a means by which the x-ray image may be spatially localised; c) a means by which at least one reconstructed image, corresponding to each x-ray image and deriving from a three-dimensional patient scan data set, may be produced; d) a means by which the reconstructed image and the x-ray images are superimposed, the positioning error being determined electronically and/or with computer guidance by way of particular landmarks and/or the intensity gradient or the contours in the two images; and e) a means by which the position of the patient is corrected with respect to a linear accelerator by way of the determined positioning error, wherein f) the device comprises only one image recorder, with which the x-ray images of both x-ray sources are produced. The advantages of using a single image recorder have already been described above. The image recorder can be an image intensifier or detector, in particular comprising amorphous silicon. In a preferred embodiment of the present invention, the image recorder is positioned on a support for a movable patient table. In this way, one or more image recorders rigidly installed in the floor of the treatment room may be dispensed with, resulting in very high flexibility. The treatment room can then easily be used for other purposes as well, without disruptive image recorders in the floor. Moreover, an image recorder positioned on a support for a movable patient table is much more easily accessible, and can therefore also be more easily serviced. The image recorder may be vertically portable together with the patient table and the support, while it is securely arranged horizontally. In other words, the patient table may be moved horizontally, independent of the image detector. If the two x-ray sources are then arranged respectively over a patient table, in particular fixed to the ceiling, and to the side, shifting the patient table sideways while the image recorder remains secured in this direction may be used to ensure that even when the radiation target is on the patient's side, an image of the radiation target always appears on the image intensifier, and in a substantially central position in the image recorder. In principle, however, the possibility also exists of arranging the two x-ray sources respectively beneath a patient table, and to the side, the image recorder then being positioned above the patient table. BRIEF DESCRIPTION OF THE DRAWINGS In the following, the invention will be explained in more detail, by way of the enclosed drawings showing preferred embodiments, in which: FIG. 1 is a radiation device in accordance with the invention, during a calibration process; FIG. 2 is two images of a calibration phantom (x-ray images of a calibration phantom); FIG. 3 is a calibration phantom; FIG. 4 is the radiation device, as x-ray images of a patient are being produced; FIGS. 5 & 6 are the production of x-ray images of a patient in two different recording positions; FIG. 7 is the scheme for projecting an x-ray image back into a normal plane; and FIG. 8 is a schematic representation of the production of two reconstructed images. DETAILED DESCRIPTION Referring to the figures mentioned above, those components of the device in accordance with the invention will now be described which are necessary for carrying out the preferred embodiment of the invention described here. The device comprises two x-ray tubes 2 , 3 mounted to the ceiling of a radiotherapy room, which in other embodiments may also optionally be fixed in or on the floor. Furthermore, an x-ray detector 6 (image recorder) made of amorphous silicon is provided, fixed to a support 5 for a patient table 4 . The x-ray detector can be moved vertically using the support 5 , the patient table 4 can however be moved horizontally, independent of the detector 6 . In other embodiments, the detector can consist of another material, or can be an image intensifier; it can also be fixed to the floor or to the ceiling, according to the location of the x-ray tubes. The device further includes an infrared tracking system with cameras 8 , 9 for tracking passive markers 10 , 13 (FIG. 3 and FIG. 7 ), wherein in principle any tracking system for tracking markers or contours can conceivably be used. The computer system for guiding the tracking system, the x-ray sources 2 , 3 , the detector 6 and optionally the patient table and in particular the gantry of the linear accelerator 1 is present, but not shown in the drawings. Furthermore, an x-ray calibration phantom 7 is available, comprising both x-ray visible markings 11 , 12 on a number of planes as well as markings 10 which may be detected by the tracking system. Optionally, the position of the phantom may also be communicated to the system via the position of the patient table 4 and a phantom placed defined on the table 4 . Additionally, the system may comprise an isocentre phantom, not shown, with the aid of which, and including the tracking system, the spatial position of the isocentre of the linear accelerator may be communicated to the computer system. In an alternative embodiment, all positions detected by the tracking system may also be read from a patient table comprising an integrated (electronic) position indicator. Conversely, positions determined without a tracking system can therefore also be approached, wherein the x-ray calibration phantom 7 then has to lie exactly on a defined marking during calibration. Moreover, a determining means should also be provided for the patient, for example rubber tensors or a vacuum means. The invention will be explained in the following by way of an extended positioning sequence, and referring to all figures for an example embodiment. In preparation, a three-dimensional image data set (for example, a series of computer tomographic images) are taken for a patient, taking care that the region to be irradiated is captured. This image data set is transferred to a radiation planning system. The desired position of the radiation target point is defined with the aid of the radiation planning system (later, during irradiation, the radiation target point defined in this way should lie in the focus of the beam of the linear accelerator (=the isocentre)). Image information, and radiation target point information referenced thereto, are transferred to the positioning system, wherein it should optionally be possible to define a number of target points which are then processed sequentially. A calibration step for the device now follows. This calibration step need not be carried out before every treatment, but only when it is suspected that the relative position of the x-ray sources has changed. When calibrating, the calibration phantom 7 is first placed directly onto the detector 6 . The spatial position of the phantom 7 is determined via the tracking system and the tracking markers 10 arranged on the phantom 7 . Then, without moving the phantom, two x-ray images are taken, which may be seen in FIG. 2 (one image per x-ray source), and read into the computer system. The projections of all x-ray visible markers in both x-ray images are then automatically detected in the computer system with the aid of image processing software; detection may also optionally take place manually. From the position of the phantom and the projections of the positions of the x-ray visible markers, the computer system calculates the three-dimensional spatial position of the x-ray sources (the focus of the beam), the three-dimensional position of the detector (the image plane) during calibration, as well as other indexing parameters. The spatial position of the isocentre of the linear accelerator is disclosed to the computer system with the aid of another phantom, as has already been described above. The patient can now be accurately positioned in accordance with the present invention. To this end, the patient P is placed on the patient table 4 and initially pre-positioned in the treatment position as accurately as possible with respect to the linear accelerator 1 . The patient may be pre-positioned via the tracking system using the markers 13 arranged on the patient; or, however, manually or by means of a different method. In the next step, the patient P is moved back out of pre-positioning using a defined offset, and into a recording position I, as shown in FIG. 5 . Recording position I is characterised by the fact that the region to be irradiated is projected onto the detector 6 using the x-ray source 3 . The patient can then be shifted by directly guiding the patient table 4 with the aid of co-ordinates and guiding the patient table 4 with the aid of the tracking system and markers 13 arranged on the patient P or on the table 4 . Furthermore, the patient may also be manually shifted. As already noted previously, recording position I lies outside the radiation range of the linear accelerator 1 , and the shifting of the patient with respect to pre-positioning is stored as “offset I”. An x-ray image (x-ray image—actual position I) is now taken with the aid of the x-ray source 3 and the detector 6 , and transferred to the computer system. The spatial position of the image detector 6 while “x-ray image—actual position I” is being taken is determined. This may be achieved by detecting edges in the x-ray image using known setting and form of the diaphragm of the x-ray source. Optionally, the position of the detector determined during calibration may be enlisted, to calculate the current position of the detector, if the detector is only moved vertically. Furthermore, it is also possible to track markings 10 arranged on the detector 6 , with the aid of the tracking system. In a further step, the patient P is now moved into recording position 11 , shown in FIG. 6 . Recording position 11 is characterised by the fact that the region to be irradiated, the radiation target point T, is projected onto the detector 6 using the x-ray source 2 . Here too, the patient can then be shifted by the measures already mentioned above. Recording position II also lies outside the radiation range of the linear accelerator 1 , and the shifting of the patient with respect to recording position I is stored as “offset II”. An x-ray image (“x-ray image—actual position II”) is then produced with the aid of the x-ray source 2 and recorded by the x-ray detector 6 , and transferred to the computer system. At this point, too, the spatial position of the image detector 6 is determined by the measures already cited previously. Following this, the reconstructed images or virtual images (DRRs=Digitally Reconstructed Radiographs) corresponding to the x-ray images are then produced. FIG. 8 schematically explains how two reconstructed images are produced. To this end, a computer tomographic scan data set 20 is used which was produced previously from the patient. It is illustrated in FIG. 8 by a multitude of cross-sectional views arranged in sequence. Using the known position data of the radiation sources 2 and 3 , which correspond here to the virtual radiation sources 16 and 15 , corresponding reconstructed images 14 a and 14 b are then generated by way of the data scanned in. In FIG. 2 , the centre-beams are designated 17 a and 17 b. The input data for producing the reconstructed images, which in the following are also called DRRs (Digitally Reconstructed Radiographs), are on the one hand the positions of the radiation sources 15 and 16 . The spatial arrangement of the plane in which the x-ray image is produced, both with respect to the distance to the radiation source as well as with respect to its inclination, must be given as the second input quantity. In other words, the virtual x-ray films 14 a and 14 b must be arranged in exactly the same way as the films or surface of the detector from the actual x-ray images, in order that the images may be superimposed. If the x-ray image plane and the direction of the centre-beam are exactly known (these parameters are determined as described previously), the corresponding DRRs can be exactly reconstructed and assigned. In this way, virtual x-ray images (DRRs) defining the “desired content” of the real x-ray images are calculated analogously to the really existing x-ray images “actual position I” and “actual position II” by the computer system with the aid of three-dimensional image data set. The procedure is as follows, wherein all steps are carried out virtually and completely by the software of the computer system: The three-dimensional image data set is positioned “correctly” in virtual space. In this case, this means that the defined radiation target point is exactly on the isocentre position known to the computer, and is correctly orientated. The image data set is then shifted virtually in the direction of the real “x-ray image—actual position I” using “offset I”. The x-ray source 3 and the detector 6 are virtually arranged spatially correctly, i.e. in the previously determined three-dimensional positions. In this case, spatially correctly means that the system parameters determined during calibration are used, with the exception of the position of the detector The position determined while “x-ray image—actual position I” is taken is considered as the position of the detector. The “desired x-ray image—DRR I” is generated by virtually transilluminating the three-dimensional image data set (taking into account the size of the detector and the scaling of the data set). “Desired x-ray image—DRR I” and “x-ray image—actual position I” are thus of equal size; “desired x-ray image—DRR I”, however, does not contain aperture shadows. The data set is then virtually shifted in the direction of the real “x-ray image—actual position II” using “offset II”. Here, too, the x-ray source 2 and the detector are virtually arranged spatially correctly, i.e. in the previously determined three-dimensional positions, which in this case means that the system parameters determined during calibration are used, with the exception of the position of the detector. The position determined while “x-ray image—actual position II” is taken is considered as the position of the detector. The “desired x-ray image—DRR II” is also generated by virtually transilluminating the three-dimensional image data set, taking into account the size of the detector and the scaling of the data set, such that “desired x-ray image—DRR II” and “x-ray image—actual position II” are of equal size, the former containing no aperture shadows. “X-ray image—actual position I” is then superimposed with “desired x-ray image—DRR I”, and “x-ray image—actual position II” with “desired x-ray image—DRR II”, the DRR in each case having already been virtually generated spatially correctly on the x-ray image. The respectively assigned images are then compared, in that the image contents are manually or automatically superimposed. In this embodiment, “image contents” primarily means projections of bone structures. In this case, the shadows of the aperture remain explicitly unconsidered in the x-ray images. The automatic “superimposing” is based on an image fusing algorithm, which may be based on intensity marks, contour marks, or landmarks. The necessary shifting of each of the “actual position” images is outputted and automatically converted to the real position of the patient. The three-dimensional dependence of the two-dimensional image pairs is likewise taken into account, i.e. shifting “x-ray image—actual position I” in the head-foot direction automatically leads to the same shifting in “x-ray image—actual position II”. The three-dimensional shifting detected in this way will be called “positioning error compensation” in the following. Where both image pairs are already 100% congruent without having been shifted, the original pre-positioning was absolutely correct and the positioning error in all spatial directions was thus zero. The patient is then moved into the correct position for treatment, by means of the tracking system, manually or by another method of shifting the patient table. This position for treatment is defined as follows: position for treatment=current position−offset II−offset I+positioning error compensation An alternative to producing the x-ray images as outlined above is to project each of “x-ray image—actual position I” and “x-ray image—actual position II” back onto a defined normal plane. This projecting back, which may be performed computationally, is shown schematically in FIG. 7 , wherein the image plane 6 ′ inclined out from the real plane of the detector 6 is intended for radiation using the x-ray source 3 . The corresponding DRRs are likewise calculated in these planes, cf. in this respect FIG. 8 . An alternative method for calculating the positioning error is based on using implanted markers, wherein an identical method to that described above is carried out, but with the following differences: the positioning principle is not based on bone structures, but on markers (e.g. 2 mm gold spheres) already implanted in the patient before the 3D-image data set is recorded; the position of the implants is detected in “x-ray image—actual position I” and “x-ray image—actual position II” (manually, or automatically by image processing software); the position of the implants is detected in the 3D-image data set (manually, or automatically on the basis of density). Desired x-ray images DRR I and DRR II, calculated thereupon, explicitly contain the projected positions of the markers. Projecting bones and soft tissues may be dropped. the positions of the markers alone are then superimposed, and a potential shift is calculated therefrom. In the case of negligible distortions, a compromise is optimised. Lastly, the positioning system in accordance with the invention can be extended further, by taking into account the breath-dependence the positions of the radiation targets. Irradiation dependent on or triggered by breathing may be achieved by the following measures: not one single image but a quick succession of a number of images (a video clip) are recorded in image recording positions I and II over a period of several breathing cycles; one or more marker arranged on the patient (preferably on the chest) are tracked by the tracking system. These markers move in accordance with breathing. Each time an image is taken by the x-ray unit, the corresponding position of the markers is stored as well; under certain circumstances, the breath-dependent movement of the target volume may be observed in the video clips. Preferably, however, markers implanted in the target volume or in the vicinity of the target volume are tracked, always being clearly recognisable in the x-ray images; by this method, the movement of internal structures may be referenced with the movement of external markers. If the two video clips from recording position I and recording position II are aligned with one another via the external markers, the 3D position of an internal structure may be concluded from the current position of the external markers; this may, for example, be used to activate the beam of the radiation device only when the target volume is within the radiation beam.

A method for accurately positioning a patient for radiotherapy and/or radiosurgery, comprising the following steps: the patient is pre-positioned as accurately as possible with respect to a linear accelerator; at least two x-ray images of the patient and/or one of the parts of his body in the vicinity of the radiation target point are produced from different respective recording angles on a single image recorder; the x-ray image is spatially localized; at least one reconstructed image, corresponding to each x-ray image and deriving from a three-dimensional patient scan data set, is produced, the reconstructed images containing the desired image contents of the x-ray images when the patient is correctly positioned; and the real x-ray images are superimposed, and the positioning error is determined electronically and/or with computer guidance by way of particular landmarks and/or the intensity gradient or the contours in the two images; and the position of the patient is corrected by way of the determined positioning error.

This is a continuation of application Ser. No. 953,119 filed on Oct. 20, 1978, which in turn was a continuation of Ser. No. 743,070 filed on Nov. 18, 1976, which in turn was a continuation-in-part application of Ser. No. 565,363 filed Apr. 7, 1975, all now abandoned. FIELD OF INVENTION The invention is directed to well completion apparatus, and particularly to a mechanism for establishing a uniform feeding rate of treatment liquid from a casing to a producing formation and for temporarily closing communication between the casing interior and the formation. BACKGROUND INFORMATION AND PRIOR ART Bore hole casings or liners are conventionally set in bore holes by a cementing process in which a cement slurry is forced down through the casing space and then upwardly around the outside of the casing to fill the annular space between the exterior casing surface and the surrounding wall of the formation. After solidification of the cement, communication between the casing and the producing zone is established by explosive perforation of the casing, e.g., by means of bullets or shaped charges which also penetrate the hardened cement to form passageways or ducts therethrough. This procedure is unsatisfactory as the bullets or charges tend to crack the cement around the passageways, thereby causing vertical communication, to wit, up and down movement around the casing from one perforation to another. This, in turn, prevents subsequent selective treatment through each perforation to the formation at the end of each duct or perforation, since injected treating material could travel up or down through cracked cement without permitting selective control at the injected places, i.e., the stratum of the formation at the end of each duct. It will be appreciated that this prior art method of establishing communication between the producing formation and the interior of the casing is particularly disadvantageous in respect of completion of the well bore, be it by acidification, sand fracking, consolidation and the like. The reason for this is that treatment liquid which is forced down the casing and through the passages in the cement into the formation, of course, travels along a path of least resistance. Liquid thus enters the formation where least resistance is offered, while no liquid, or only minor amounts of liquid will penetrate formation strata which offer more resistance. Moreover, large amounts of liquid are wasted within the cracks and fissures within the cement wall. The injection of treatment liquid thus takes place in a most non-uniform manner, and no uniform flow rate of liquid through the various passages leading from the holes in the casing and through the cement into the formation is accomplished. This is particularly disadvantageous, when some or all of the passages are to be selectively blocked by sealing means, usually referred to in the art as ball sealers. Thus, in practice, when it is desired to block off communication between the formation and the passages, which lead from the formation through the cement into the casing interior, ball sealers are suspended in the treatment liquid, the ball sealers having substantially the same specific gravity as the treatment liquid. The intention is for the ball sealers to enter the passages and to block them. However, since the flow rate is non-uniform, it will be appreciated that the ball sealers, of course, have the tendency to enter only those passages through which liquid flows at a sufficient rate while no balls will be forced into the passages through which there is only a trickle or no flow of treatment liquid. More recently, an improved method and device for establishing communication between the casing and the producing zone has been suggested. According to this suggestion, a plurality of duct-forming devices are welded or otherwise secured to the outside of the casing in alignment with holes machined into the casing wall. These duct-forming devices comprise telescoping tubes or sleeves which are in a retracted position during the positioning of the casing in the bore hole. When contact with a producing zone is to be made, these telescoping tubes are caused to project substantially horizontally toward the formation wall to make contact with the pay zone and to establish a permanent link between the pay zone and the casing. The cement slurry is introduced into the space between the casing and the formation wall immediately before the lateral telescoping of the tubes so that the cement sets around the tubes and the casing. The telescoping tubes of the duct-forming devices, as previously proposed, are made of steel or the like acid- and alkali-resistant metal and the outer, free tube end which ultimately contacts the producing formation is blocked by an acid and/or alkali soluble metal plug which is lodged within the tube in a sealing manner so as temporarily to prevent passage of material through the tube. When communication between the pay zone and the interior of the casing is to be established, an acidic or alkaline liquid is forced down the casing and into the laterally extending telescoping tubes to cause dissolution of the plug. The present invention is directed to an improvement of metallic duct-forming devices of the kind referred to hereinabove, such duct-forming devices having been disclosed in a number of U.S. patents, for example, Nos. 2,775,304, 2,707,997, 2,855,049, 3,245,472, and 3,425,491, to which specific reference is had. While the duct-forming devices referred to above constitute an important improvement in the art of well completion and recovery of formation fluids, the known duct-forming devices still do not permit effectively to establish a sufficient feeding rate for treatment liquid into the formation. Thus, when the acid-soluble plug has been dissolved, treatment liquid such as acid or sand-containing fracking liquid, which is forced down the casing will enter the formation through the duct-forming devices also along a path of least resistance. Further, when blocking of selected duct-forming devices by ball sealers is intended, the non-uniform feed rate previously referred to also applies to well completion apparatus in which duct-forming devices of the prior art are used. SUMMARY OF THE INVENTION It is the primary object of the invention to overcome the disadvantages of the prior art procedures and devices referred to and to provide a duct-forming device with a closure mechanism which permits entry of liquid from the casing interior into the formation at a predetermined flow rate and in a predetermined volume, to prepare the formation for subsequent treatment, such as acidification, fracking and the like, and which blocks the communication between the formation and the casing interior when a sufficient feed rate for liquid from the casing into the formation has been established. It is also an object of the invention to provide a closure mechanism of the indicated kind which, after the desired feed rate has been established, is removed from the duct-forming device and pushed into the casing and thus falls to the bottom of the well, when the formation pressure exceeds the pressure within the duct-forming device, so that formation fluids, such as petroleum or gas, can freely enter the duct-forming device and flow into the casing interior. Generally, it is an object of the invention to provide improved apparatus for completing and treating wells. Briefly, and in accordance with the invention, the duct-forming device has a terminal sleeve which is adapted to make contact with the producing formation. This terminal sleeve, at its outer free end, has at least one passage which may trasverse an acid and/or alkali-soluble plug, screwed or otherwise fitted into the free end of the terminal sleeve. This passage thus establishes communication between the formation and the interior space of the duct-forming device. A removable piston assembly is arranged within the interior space of the duct-forming device. This removable piston assembly includes a piston having passageways. The piston is movable between an initial position in which the piston is located away from the passage in the plug of the terminal sleeve so as to permit fluid flow through the passage of the plug, and a blocking position in which the piston blocks the fluid flow through the duct-forming device. In one embodiment of the invention, the piston assembly, in addition to the piston proper, may include shoulder or abutment means which are press-fitted or otherwise removably lodged within the duct-forming device, and a spring having ends bearing against the shoulder or abutment means to urge the piston into its initial position away from the passage of the plug. This construction, moreover, comprises a flow-impeding member which is located behind the piston assembly of the casing, the flow-impeding member being in the form of a plate or the like, which is soluble in acid and/or alkali and thus prevents contact of liquid intended to flow from the casing interior into the duct-forming device until the flow-impeding member has been consumed or dissolved by acid or alkali. Considering the very substantial hydraulic pressures with which well completion apparatus of the indicated kind are operated, the construction also includes a closure or safety cap which is screwed or otherwise secured to the end of the duct-forming device which is attached to the casing wall. This closure cap is also made of a material which is consumable by or soluble in acid and/or alkali and has at least one hole, preferably centrally located. Liquid forced down the casing thus enters the hole in the closure cap and makes contact with the flow impeding member. From a practical point of view it is advantageous to provide several holes in the closure cap in order to facilitate circulation and escape of gases which are evolved during the dissolution of the closure cap and the flow impeding member. When the liquid, be it alkaline or acidic, has eaten through the flow impeding member, the liquid thus flows through the passages in the piston and through the passage in the plug toward and into the formation where it breaks down and loosens the formation composition. The piston assembly construction is such that with increased pressure and/or volume of the liquid entering through the flow impeding member, the force of the spring will be ultimately overcome so that the piston of the piston assembly is gradually moved into its blocking position in which the piston blocks communication from the formation through the passage in the plug and into the interior of the duct-forming device. The system is now closed and when production is to be initiated, the pressure within the casing is relieved, for example, by swabbing, so that the formation pressure will exceed the pressure within the duct-forming device. Formation fluid now pushes the piston towards the casing and once the flow impeding member and the closure cap have been consumed or dissolved by the alkaline or acidic liquid, there is nothing to hold the piston assembly within the duct-forming device which thus is forced towards the casing where the piston assembly falls into the bottom of the bore hole. A free passage is now established for incoming formation fluids. It will be appreciated that due to this arrangement a sufficient flow rate into the formation can be established before the piston assumes the blocking position. When it is desired to close selected ducts and for this purpose, in accordance with prior art procedure treatment liquid is forced down the casing with suspended ball sealers, the ball sealers, due to the uniform flow rate through the several ducts located at various levels along the casing wall, enter each of these passages, and not only those through which liquid flows along a path of least resistance. In accordance with some of the more specific embodiments of the invention, the piston assembly may be formed with differing configurations particularly with regard to the formation of passageways therethrough or therearound which operate to permit liquid to flow through and/or around the piston assembly after the flow-impeding member has been dissolved. For example, in one embodiment, the piston may be formed with internal passageways to which the liquid may flow. Alternatively, or in conjunction with the internal passageway, the piston assembly may be formed with a fluted piston structure which permits liquid flow about the exterior of the piston, simultaneously with or instead of flow through internal passageways. By a further important aspect of the invention, the piston which forms the basic element of the piston assembly is itself made to be soluble upon sufficient exposure to the acid and/or alkali liquid. In this embodiment, a ball check arrangement is used to terminate flow through the duct forming device after the dissolution of the various parts of the device. This embodiment is generally similar to the previously described embodiments and includes a safety cap, flow-impeding means and a plug all of which are formed of material which is acid and/or alkali soluble. As the liquid is introduced into the casing, and after the telescoping duct-forming device has been extended to bring its forward end into contact with the formation wall, dissolution of the flow-impeding member will cause liquid to come into contact with the piston member, which, since it is no longer movable is more appropriately referred to as a check member. Although the check member is acid and/or alkali soluble, until the liquid actually is pumped through the casing, the check member will not dissolve because it is made with an outer casing which is very slowly soluble in the liquid. When the well is to be stimulated and the liquid is pumped down the casing, a certain amount of flow wll be produced around the exterior of the check member and through the end plug. As the plug and the check member become dissolved, a ball check member originally located between the piston and the flow-impeding member will become seated upon a valve seat defined within the duct forming device thereby closing the flow path therethrough. However, as the pressure in the welbore is reduced, flow from the formation will displace the ball check allowing it to move into the casing and opening the passage for return flow. The various features of novelty which characterize the invention are pointed out with particularity in the claims annexed to and forming a part of this disclosure. For a better understanding of the invention, its operating advantages and specific objects attained by its use, reference should be had to the accompanying drawings and descriptive matter in which there are illustrated and described preferred embodiments of the invention. FIG. 1 is a sectional top view of a duct-forming device secured to a casing and positioned within a bore hole, the duct-forming device being in the initial, retracted position; p FIG. 2 is a longitudinal sectional view corresponding to that of FIG. 1 but showing the duct-forming device after it has been projected into its operative position toward the formation wall; FIG. 3 is a view corresponding to FIG. 2 with the piston in the blocking position; FIG. 4 is a view corresponding to FIG. 3 with the piston assembly on its way to the ultimate position on the bottom of the wellbore; FIG. 5 is a partial sectional view of the duct-forming device of the invention showing a configuration of the piston in accordance with an alternative embodiment of the invention; FIG. 6 is a partial sectional view showing a further embodiment of the invention wherein there is utilized a fluted piston devoid of internal passages; FIG. 7 is a perspective view of the fluted piston utilized with the embodiment depicted in FIG. 6; FIG. 8 is a partial sectional view showing still another embodiment of the invention wherein there is utilized a fluted piston having internal passageways; FIG. 9 is an end view of the piston utilized in the embodiment depicted in FIG. 8; FIG. 10 is a side elevation of the piston shown in FIGS. 8 and 9; FIG. 11 is a sectional view of a different embodiment of the duct-forming device of the present invention wherein a soluble check member is utilized with the device being shown in a position similar to the position depicted in FIG. 1 secured to the casing with the duct-forming device in its initial, retracted position; FIG. 12 is a sectional view corresponding to that of FIG. 11 but showing the duct-forming device after it has been projected into its operative position toward the formation wall; FIG. 13 is a view corresponding to that of FIG. 12 showing the device with the end cap and the flow impeding member dissolved but prior to dissolution of the check member; FIG. 14 is a sectional view corresponding with FIG. 13 wherein all of the soluble elements have been dissolved and with a ball check located to block flow through the duct-forming device; and FIG. 15 is a sectional view corresponding to the view of FIG. 14 showing the ball check being displaced from its seated position upon the occurrence of return flow through the duct-forming device from the formation. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring now to the drawings, and in particular FIGS. 1 and 2, a duct-forming device, generally indicated by reference numeral 100, is secured to the external surface of a bore hole casing 10, which is shown fragmentarily only. For this purpose, the bore hole casing 10, which has a machined hole or opening 99, is provided with a nipple or mounting boss 98, which is welded or otherwise secured to the exterior casing surface, as indicated by reference numberal 97. The duct-forming device 100 has a hollow, cylindrical rear mounting portion 96, whose external threads 95 mesh with the internal threads 94 of the nipple 98. An O-ring or sealing means 93 is interposed between the rear mounting porton 96 and the nipple 98. The duct-forming device 100 comprises moreover two tubes or sleeves 92 and 91 which are arranged in telescoping manner and are shown in FIG. 1 in their initial or retracted position in which the casing is lowered into the well bore 90, the formation wall of the well bore being indicated by reference numeral 89. In practice, many duct-forming devices 100 are secured to the casing 10 at spaced levels and locations thereof. The construction so far described is similar to or the same as that of prior art duct-forming devices, such as, for example, disclosed in U.S. Pat. Nos. 3,245,472, 2,855,049, and 3,382,926. The duct-forming device moreover comprises, in conventional manner several O-rings 4, 68, 87, 86, 85, 84, 83 and 82 for permitting the telescoping and ultimate positioning of the tubes or sleeves 92 and 91 in fluid-tight manner. Shear rings or wires 81 and 80 are provided between the sleeves or tubes 92 and 91, the shear rings or wires being capable of breaking upon application of a predetermined pressure. Locking flanges or protruberances 79 and 78 prevent rearward movement of the sleeves 92 and 91 once they have reached their ultimate extended position. The duct-forming device 100 defines an interior space or passage 77 which accommodates a removable piston assembly, generally referred to by reference numeral 50. The piston assembly comprises a piston proper 49 which defines one or several passages 48. The rear portion of piston 49 forms a chamber 47 which accommodates a ball 46. A seat 45 for the ball is located within the chamber 47. A plug 38 is screwed into the free end of the sleeve 91, intermeshing threads 37 being provided for this purpose. It will be noted that the external surface of the plug 38 is substantially flush or in alignment with the outer extremity of the sleeve 91. The plug 38, which is preferably of acid or alkali soluble metal, has passageway means passing therethrough, one passage 35 being shown in the Figures. The interengaging threads 37 have a relatively lose fit so as to permit a trickle or light flow of fluid therethrough in the positions shown in FIG. 2. The rear end of the duct-forming device 100 is fitted with a closure or safety cap 30 of a metal, for example, zinc, zinc alloy, aluminum or aluminum alloy, which is soluble by or consumable in acid or alkali. The closure cap 30 is screwed onto the mounting portion 96 of the duct-forming device, as indicated by the threads 29. This closure cap has at least one hole 28 which, as shown in the drawing, is centrally located. From a practical point of view it may be advantageous to optionally provide additional holes 28a, 28b closer to the circumference of the cap 30 as shown by way of example in FIG. 1. Between the cap 30 and the piston assembly 50 there is interpositioned a flow-impeding member 26, which is also made of a metal, for example, magnesium, magnesium alloy, aluminum, aluminum alloy, zinc or zinc alloy, which is soluble in acid and/or alkali. The flow impeding member, which is in the form of a plate, is screwed into the sleeve 91, as indicated by the threads 19. The piston 49 forms an abutment or shoulder portion 18, a second abutment or shoulder 17 being press-fitted into the front portion of the sleeve 91. A spring 16 bears against the shoulders 18 and 17 and thus urges the piston 49 towards the casing into contact with the flow-impeding plate 26. The interior space 77 of the duct-forming device is initially preferably filled with a viscous liquid, such as petroleum jelly, indicated by reference numeral 15, thus preventing entry of substances from the bore hole. The operation of the device is substantially as follows After the casing, with the duct-forming devices 100 being secured thereto in the retracted position, has been positioned in the bore hole and prior to the setting of the cement which customarily fills the bore hole space between the formation wall 89 and the casing 10, the tubes or sleeves 92 and 91 of the duct-forming device 100 are projected towards the formation to assume the position shown in FIG. 2. This is done by pressurizing the casing, for example, with acidic or alkaline liquid which presses against the flow-impeding plate 26, the pressure being sufficient to break the shear wires 80 and 81. A more detailed explanation of the manner of extending the tubes or sleeves 91 and 92 is contained, for example, in U.S. Pat. No. 3,245,472, to which reference is bad. Since the projection of the tubes 91 and 92 into the position of FIG. 2 does not form part of the present invention, no additional explanation is necessary. Once the tubes have assumed their extended position of FIG. 2, they are held in this position by members 78 and 79. After the duct-forming device 100 has been extended into the position of FIG. 2, the piston assembly 50, including the piston 49, still bears under the spring pressure of the spring 16 against the flow impeding member 26. The liquid which, as stated, may be of acidic or alkaline nature, is forced down the casing and enters the hole 28 in the closure cap 30 and gradually dissolves the flow impeding means 26 and the metal surrounding the hole 28 of the closure cap. It should be noted in this context that due to the very significant pressure customarily employed for the liquid, the construction including the safety or closure cap 30 having a centrically located hole or bore is particularly advantageous to prevent the tubes of the duct-forming device from being hurled out towards the formation. Once the liquid has eaten through the flow impeding member 26 to a sufficient degree so as to pass therethrough, the liquid flows through the passages 48 in the piston 49, thus forcing out the viscous liquid 15 through the passage 35 in the plug 38. The liquid thus enters the formation where it breaks up the formation structure. In the initial stages, when the flow impeding member 26 has been eaten through to a partial extent only and thus still offers resistance, the flow of liquid through the interior space 77 of the duct-forming device will be rather slow and the amount of liquid entering the formation will thus be relatively small. However, it will be appreciated that once the flow-impeding member and the closure cap have been substantially dissolved by the liquid, the flow of liquid gradually increases until the pressure of the liquid entering the interior space 77 of the duct-forming device is sufficient to overcome the spring action of the spring 16 and to push the piston 49 against this spring action to such an extent that the piston 49 is gradually moved from its initial position of FIG. 2 into the position shown in FIG. 3, in which the piston thus blocks the flow passage through the duct-forming device. As shown in FIG. 3, this occurs as a result of engagement of the piston within the O-ring 4. Of course, it will be seen that until this point sufficient liquid has flowed to substantially or completely dissolve the plug 38 thus leaving the duct forming device capable of permitting return flow. The engagement between the piston 49 and O-ring 4 prevents also leakage of fluid through the threads 37. In this position which, as stated, is shown in FIG. 3, the ball 46 is retained within the chamber 47 by a suitable retaining member 3. The movement of the piston 49 from the position of FIG. 2 to that of FIG. 3 is thus dependent on the amount and pressure of the liquid. These criteria can be readily adjusted by the operator thus enabling entry of predetermined amounts of liquid into the formation before the passage through the duct forming device is blocked by the piston 49. It will also be appreciated that the effect and action are essentially the same in all the duct-forming devices mounted on the casing 10 and that, when the piston assemblies of all the duct-forming devices have assumed the position of FIG. 3, substantial amounts of treatment liquid have already passed into the formation to break up the formation, thereby establishing a substantially uniform flow rate into the formation from the casing through all the duct-forming devices. Communication between the formation and the casing has thus been effectively blocked when the piston assemblies of the duct-forming devices have assumed the position of FIG. 3. When production is to be initiated or when further treatment of the formation is desired, for example, by acidification or fracking, for example, sand fracking, it is, of course, desired that the interior space of each of the duct-forming devices is substantially clear so as to permit free flow of fluids. Accordingly, and pursuant to the invention, the piston assembly of the duct-forming device should be removed. Since the procedure so far described is relatively time-consuming, it will be appreciated that the plug 38, the flow impeding member 26 and the closure cap 30 have at this stage been substantially completely dissolved. This means that there is nothing to prevent the piston assembly 50 from moving towards and into the casing interior, provided, of course, sufficient pressure is exerted in the direction towards the casing. Accordingly, in order to remove the piston assembly, pressurization is discontinued and the casing may be swabbed to a point at which the formation pressure is greater than the pressure within the casing interior and the inner space of the duct-forming device. When this occurs, formation fluid, enters the duct-forming device to push the entire assembly 50 toward and into the casing. In order to facilitate the removal of the piston assembly, the ball 46 is provided which is thus forced against its seat 45 to offer additional resistance thus building up the pressure and facilitating removal of the entire piston assembly, as indicated in FIG. 4, in which the piston assembly 50, including the spring, are just in the process of falling into the casing and to the bottom of the well bore. It will be understood that if treatment or stimulating liquid is now again forced down the casing and its pressure exceeds the formation pressure, the treatment liquid will freely and uniformly flow through all the duct-forming devices and the problem of flow according to the path of least resistance is essentially minimized, if not entirely overcome. Ball sealers suspended in treatment liquid will enter each of the duct-forming devices. If sand fracking is intended and, depending on the size of the duct-forming devices, large volumes of sand can be readily introduced into the formation through the inventive duct-forming devices. Since the duct-forming devices are subject to substantial friction and abrasive forces, both during the positioning of the casing--the duct-forming devices rub against the formation wall--and during the subsequent treatment procedures, for example, sand fracking, it is recommended to make the entire duct-forming device, or at least those portions which are subjected to wear and friction of hardened steel. Moreover, it may be preferred to line the interior passage of the duct-forming devices with wear-resistant lining material, such as, for example, tungsten or ceramic material as indicated at Z in FIG. 2. A further embodiment of the present invention is shown in FIG. 5. The embodiment depicted in FIG. 5 differs from the embodiment of FIGS. 1-4 in that a bleed hole 102 is provided through the piston 49. The embodiment of FIG. 5 is essentially identical with the previously disclosed embodiment except for the fact that after the nose of the piston 49 becomes engaged within the O-ring 4 to terminate the main flow of liquid through the duct-forming device, a small amount of bleed liquid continues to flow through each of the duct-forming devices 100 by virtue of the bleed hole 102. As will be seen from FIG. 5, liquid flowing through the duct-forming device will flow through the passages 48 but this flow will be blocked by virtue of the engagement of the outer surface of the nose of the piston 49 within the O-ring 4. However, since the bleed hole 102 is located centrally of the piston, fluid entering the chamber 47 will be by-passed around the blocking engagement between the piston nose and the O-ring 4 and will be permitted to flow into the formation as indicated. It should be understood that the size of the hole 102 determines the quantity of liquid which is permitted to flow into the formation and it should be considered that the hole 102 is to be made rather small and constitutes a bleed hole wherein a controlled amount of additional liquid may be permitted to leak or bleed into the formation. Otherwise, the operation of the embodiment of FIG. 5 is essentially identical with that described in connection with the embodiment of FIGS. 1-4. Another embodiment of the present invention is depicted in FIGS. 6 and 7. In the embodiment of FIGS. 6 and 7 a piston 149 is utilized which is formed with a fluted outer configuration with the overall arrangement of this embodiment being such that the need for a ball check is eliminated. The embodiment of FIGS. 6 and 7 is essentially similar to the embodiments previously described except for the outer configuration of the duct-forming device which extends into abutment with the wall 89 of the formation. As indicated in FIG. 6, the embodiment depicted therein is formed with a flow impeding member 126 similar to the flow impeding member 26 of the previously described embodiment. A sleeve 191 which constitutes the terminal sleeve of the telescoping duct forming device and which is essentially analogous to the sleeve 91 of the previously described embodiments, has formed therein an interior passage 177 defined by an inner cylindrical wall 122. The piston 149 which is slidably positioned within the interior passage 177 is formed with a basically cylindrical body structure 130 and with a forward nose portion 132 and a rearward closure member 110. A plurality of flutes 112 are positioned about the outer surface of the piston with axially extending spaces being provided between the flutes. The flutes 112 are shaped with a generally trapezoidal cross sectional configuration and with their outer curved surfaces essentially conforming with the curvature of the wall 122. Thus, with the piston 149 in position within the passage 177, as indicated in FIG. 6, a plurality of axially extending flow passages 114 will be formed between the flutes 112 with one side of the flow passages being defined by the wall 122. The piston 149 is biased rearwardly or to the right, as seen in FIG. 6, by a spring 116 which is engaged between the left faces of the flutes 112 and a shoulder 134 formed within the sleeve 191. The biasing force of the spring 116 urges the piston against a check disc 104 having an opening 106 defined therethrough and also having defined thereon a valve seat 108 against which the closure member 110 of the piston 149 may become seated. By virtue of the urging force of the spring 116, the closure member 110 will become engaged against the seat 108 tending to close off liquid flow through the orifice 106. During the operation of the device, and referring back to the description previously set forth herein, dissolution of the flow-impeding member 126 will cause liquid to impinge against the closure member 110. Depending upon the fluid pressure of the liquid and upon the spring biasing force of the spring 116, the piston 149 will tend to move leftwardly with increased liquid pressure thereby tending to unseat the closure member 110 from the seat 108. As a result, liquid will tend to flow through the orifice 106 and through the passages 114. Depending upon the fluid pressure of the liquid, the piston may become further urged laterally against the force of the spring 116 tending to maintain the liquid flow through the passage 177. If the fluid pressure of the liquid being introduced into the casing 10 is properly maintained, the piston 149 may be held in balance between its left-most and right-most position and during this time the acid and/or alkali liquid will flow through the duct-forming device and through the passage 177 into the formation. The left end of the sleeve 191 is fitted with a plug 138 similar to the plug 38 of the previously described embodiments which includes a passage 135. The plug 138 may be made of acid and/or alkali soluble material and when sufficient liquid flow through the passage 177 has occurred, the plug 138 will dissolve thereby opening the end of the sleeve 191. When adequate liquid has been caused to flow into the formation through the passage 177, the liquid pressure within the casing 110 may be increased to completely overcome the force of the spring 116. When this occurs, the nose 132 of the piston 149 will be brought into abutment with the end of the sleeve 191 thereby closing off any further liquid flow from the casing into the formation. As long as the liquid pressure within the casing 10 is maintained at an adequate level, the piston 149 will be pressed against the end of the sleeve 191 and the nose 132 will block the opening therein and prevent further liquid flow into the formation. When it is desired to reverse the flow through the duct-forming device, the liquid pressure within the casing may be diminished and when the pressure of the liquid within the formation is high enough, a reverse flow will occur and the piston 149, the check disc 104 and the spring 116 will be driven through the duct-forming device and into the casing in a manner similar to that previously described in connection with the piston assembly 50 and depicted in FIG. 4. It will be noted that once the flow impeding member 126 has become dissolved, the check disc 104 will be free to move rightwardly as viewed in FIG. 6 and the check disc as well as an O-ring 136 will be driven backwardly through the duct-forming device and into the casing 10. It will be noted that in the embodiment of FIGS. 6 and 7, a mode of operation basically similar to the operation of the previously described embodiments is involved except that the need for a ball check such as the ball 46 is eliminated and except for the fact that the piston configuration is somewhat different. In either case, flow through the duct-forming device into the formation of the acid and/or alkali liquid is terminated by operation of the piston, such flow having been induced after dissolution of certain acid and/or alkali soluble members. When it is desired to effect a reverse flow from the formation, the members located within the duct-forming device may be readily displaced therefrom and drawn into the casing by the flowing liquid. A still further embodiment of the invention is shown in FIGS. 8, 9 and 10. The embodiment of FIGS. 8, 9 and 10 differs from the embodiment of FIGS. 6 and 7 essentially only in the inclusion of bleed holes which will permit some flow of liquid into the formation after the piston has moved to block further flow of the acid and/or alkali liquid through the duct-forming device. In this sense, the embodiment of FIGS. 8, 9 and 10 is essentially the embodiment of FIGS. 6 and 7 including a modification of the type provided by the embodiment of FIG. 5. In the embodiment of FIGS. 8, 9 and 10, there is provided a piston 149a which is essentially identical with the piston 149 of FIGS. 6 and 7 except that there is included a bleed passage 120 comprising a pair of bleed channels 120a and 120b. Except for the inclusion of the bleed passage 120, the piston 149a is identical in structure and operation with the piston 149. In the operation of the device of FIGS. 8, 9 and 10, when the piston 149a has been moved leftwardly into abutment with the end of the sleeve 191 to block the main flow of acid and/or alkali liquid through the flow channel 177 of the duct-forming device, a certain amount of liquid will bleed or trickle through the bleed passage 120 and into the formation. It will be clear that the piston 149a is essentially identical in all other regards with the piston 149 and that the bleed passage 120 operates in a manner basically similar to the bleed hole 102 of the embodiment of FIG. 5. Thus, after the piston 149a has been moved leftwardly to block the main flow of acid and/or alkali liquid through the passage 177, the amount of liquid which is permitted to bleed into the formation will be determined by the size and configuration of the passage 120 including the channels 120a and 120b. Of course, the piston 149a is formed with the flutes 112 defining the axial flow passages 114 and when the piston is moved to its left-most position, the liquid will first flow through passages 114 and then through the bleed passage 120 into the formation. Of course, when reverse flow from the formation occurs, the piston 149a and associated parts will be drawn backwardly into the casing in a manner similar to that previously described with other embodiments of the invention. A further embodiment of the invention involving more significant structural modifications is depicted in FIGS. 11-15. This embodiment essentially differs from the previous embodiment at least by virtue of the fact that the piston member is itself replaced by a check member which is soluble in the acid and/or alkali liquid. In the embodiment of FIGS. 11-15 there are provided many elements which are identical with elements provided with the embodiment of FIGS. 1-4. In this embodiment the casing 10 is provided with a nipple or mounting boss 98 welded or otherwise mounted thereto as at 97. A cylindrical rear mounting portion 96 is provided as well as an O-ring 93 interposed between the rear mounting portion 96 and the nipple 98. The duct-forming device of FIGS. 11-15, generally designated by the reference numeral 200 comprises moreover a rear closure cap 230 similar to the closure cap 30 of FIGS. 1-4 and a pair of tubes or sleeves 291, 292 which are at least quite similar in their structure and operation to the sleeves 91, 92 of FIGS. 1-4. As will be apparent from the description which follows, the general overall mode of operation of the embodiment of FIGS. 11-15 is quite similar to that of the embodiment of FIGS. 1-4. The embodiment of FIGS. 11-15 includes similar elements such as O-rings 83, 84, 85, 86, 87 and 88 for permitting telescoping and ultimate positioning of the sleeves 291, 292 in a fluid type manner. Furthermore, shear rings 80 and 81 are also provided between the sleeves or tubes 291, 292 with locking flanges 78, 79 operating, in a manner similar to those of the embodiment of FIGS. 1-4 to prevent rear movement of the sleeves 291, 292 once they have reached their ultimate extending position. A plug 238 is screwed into the free end of the sleeve 291 and it will be noted, particularly from FIG. 12, that when the duct-forming device 200 is in its extended position, the left hand end of the sleeve 291 and the plug 238 will be in contact with the bore wall 89 of the well bore 90. Positioned within the duct-forming device 200 is a flow-impeding member 226 and a check member 249 with a ball 246 interposed therebetween. The flow impeding member 226 is screwed into the sleeve 291 as indicated by threads 219. After the cement which customarily fills the bore hole space is in place, the duct-forming device 200 is projected to its telescoped position depicted in FIG. 12 in a manner similar to that previously described. A plug may be seated in the bottom of the casing 10 and the duct forming devices may be extended by pressurizing the inside of the casing to a pressure of about 1500 to 2000 psi greater than that which obtains in the column of wet cement in the annulus between the casing and the formation at a subsurface depth equal to that at which the duct-forming devices are fixed to the casing. This pressure is sufficient to shear the rings 80, 81 holding the duct-forming devices in their nested mode. When the rings are sheared, water or mud being used to pressure the inside of the casing 10 will flow through the orifices 228 in the closure caps 230 forcing the sleeve 291 of the duct-forming device against the formation wall. The device is provided with locking flanges 78, 79, or similar check rings or the like, which will prevent the assembly from moving away from its contact with the formation even though the pressure inside the casing may be reduced. After the cement has hardened and the operators desire to complete the well, the mud or water in the casing is displaced with the acidic and/or alkaline liquid. The liquid is allowed to remain in the casing for a sufficient time to dissolve the rear closure cap 230. In addition, the liquid also operates to dissolve the flow-impeding member 226. The piston or check cylinder 249 is made of acid and/or alkali soluble material. However, the ball check 246 is not. So long as the acid is not pumped through the duct-forming devices, the check cylinder or piston 249 will not dissolve because the side of the check member closest to the casing 10 is made of a material which is very slowly soluble in acid. Thus, in forming the member 249, it may be desirable to make its rightmost end as viewed in FIG. 12, from a material which dissolves more slowly in the acid than the other parts of the check member 249. In a preferred embodiment of the invention, the member 249 is formed with a coating 249a of more slowly soluble material. This may be accomplished in a number of methods such as coating the rear end of the member 249 with a plastic or utilizing a member which is coated with a slowly soluble metal alloy. Of course, other similar expedient obvious to those skilled in the art may be used. The spacing between the outer walls of the member 249 and the inner walls of the sleeve 291 is filled with grease or other similar substance indicated at 215. When the well is to be stimulated, acid is pumped down through the casing and into the duct-forming devices. The acid will displace the grease 215 which fills the interior spaces between the piston 249 and the sleeve 291 and the acid will then flow around the piston 249 and through orifices 235 extending through the plug 238. As will be noted from FIG. 12, the member 249 is configured so that certain spacing will be provided between the inner walls of the plug 238 and of the sleeve 291 and the outer surface of the member. As a result thereof, passage means 248 extending around the exterior of the member 249 will be provided. It will therefore be apparent that the check member 249 essentially constitutes a restriction in the passageway means of the terminal sleeve 291. After dissolution of the flow-impeding member 226, the device of the invention will be in the condition depicted in FIG. 13. As the acid is pumped down the casing, and after the grease which fills the spaces between the check member and the sleeve 291 has been displaced, the acid will flow around the member 249 through the passages 248 and through the orifices 235 in the plug 238. The member 249 and the plug 238 may be made of acid and/or alkali soluble material, for example, an acid soluble metal such as magnesium, aluminum, zinc, etc. and as the acid flows these elements will be slowly dissolved. The body proper of the member 249 and the external coating may be formed of a composition such as to prevent the ball 246 from closing the duct forming devices until a predetermined volume of acid has passed through the duct-forming device into the formation. For example, in laboratory tests, check members made of a zinc-tin-lead-copper alloy dissolve in about two hours thus preventing the ball 246 from closing during this time. Acid flowed through a test duct-forming device formulated in accordance with the present invention at an initial rate of a few gallons per minute and this rate was increased to a final rate approaching 42 gallons per minute (one barrel per minute). The average rate of 20 gallons per minute resulted in a total acid throughput of about 2400 gallons through the device. In the example referred to, the acidization treatment of each duct-forming device would allow about 2400 gallons to add to the formation at each of the duct-forming device locations before the device was closed. The closing of the duct-forming device occurs as a result of engagement of the ball check 246 against a valve seat formed interiorly of the sleeve 291. The preferred embodiment for the ball check 246 is a composition of a relatively rigid core with a resilient outer covering. The sleeve 291 is formed with internal threads 237 which engage the plug 238. Adjacent the threads 237 there is formed an annular wall 260 having a diameter smaller than the diameter of the ball 246. As a result, a valve seat 262 is defined about the periphery of the annular wall 260. When the plug 238 is dissolved, as indicated in FIG. 14, an orifice 266 extending to the end of the sleeve 291 will be formed by the threads 237 and the annular wall 260. As the member 249 becomes totally dissolved by the acid flow previously described, the ball 246 will become seated against the seat 262 thereby closing the orifice 266 and preventing additional acid flow through the duct-forming device. The rigid core of the bass 246 prevents the ball from being forced through the orifice or hole 266 at the front end of the sleeve 291. The resilient covering on the ball 246 facilitates a tight closure against the seat 262. As each of the duct-forming devices closes in a manner indicated in FIG. 14 by abutment of the ball 246 against the seats 262, the acid which is forced into the casing will enter the formation through the remaining duct-forming devices which are still open and which have not as yet had any appreciable acid through put. This results in acidization of all the duct-forming device locations thus allowing fluid flow from the casing into the formation at the maximum pressure possible with the type of casing in the hole and the acid pumping equipment being used. When all of the acid has been displaced or when all of the duct-forming devices that will accept fluid flow have closed, the pressure in the wellbore is reduced. This will allow flow to occur from the formation into the wellbore and this flow will displace the check balls 262 allowing them to move into the wellbore or the casing, as seen in FIG. 15. The bulk of the balls 246 may be retreived with a "basket" assembly well known in the oil technology field, or they may be left in the bottom of the casing assuming that some length of blank casing is available between the lowest duct-forming device and the plugged back bottom of the hole. While specific embodiments of the invention have been shown and described in detail to illustrate the application of the inventive principles, it will be understood that the invention may be embodied otherwise without departing from such principles.

A duct-forming device is disclosed for use in a well completion apparatus of the kind, wherein a bore hole casing is positioned in a bore hole and duct-forming devices of alkali- and acid-resistant metal--such as steel--are secured at spaced levels to the casing in alignment with holes machined in the casing wall. In accordance with the invention, a closure device is arranged within the duct-forming device which permits flow of predetermined amounts of liquid, such as acid, from the interior of the casing through the duct-forming device and into the producing formation, while gradually being moved by the liquid into a position in which such fluid flow is prevented. After the fluid flow has been stopped by the closure device and when the formation pressure exceeds the pressure within the duct-forming device and the casing, fluid from the formation then forces the closure device toward and into the casing space to permit thereafter free flow of formation fluid into the duct-forming device and the casing or of pressurized treatment liquid from the casing into the formation. The inventive arrangement permits inter alia the establishment of a sufficient and substantially uniform feeding rate of treatment liquid, such as acid, from the casing into the producing formation through all the duct-formers in preparation for subsequent acidification or other treatments, such as sand fracking.

FIELD OF THE INVENTION [0001] The present invention relates to particle analyzers, methods for analyzing particles, and computer programs, and in particular, to a particle analyzer for analyzing particles based on an image including particles, a particle analyzing method for analyzing particles based on the image including particles, and a computer program for realizing the particle analyzing method. BACKGROUND [0002] A particle analyzer including an extraction means for extracting a particle image from an imaged image is conventionally known (see e.g., US 2007-0273878). [0003] US 2007-0273878 discloses a particle analyzer capable of obtaining morphological feature information such as size and shape of the particles contained in a sample liquid by imaging and analyzing particles contained in the sample liquid. In such particle analyzer, the particle image is extracted from the imaged image by using the difference in luminance between the background portion and the particle image portion of the imaged image. In other words, the particle image is extracted from the imaged image by setting a predetermined luminance value as a threshold value, and setting the portion which luminance is larger than the threshold value and the portion which luminance is smaller than the threshold value of the imaged image as the particle image portion and the background portion, respectively. The particle analyzer of US 2007-0273878 is configured to extract the respective particle image from each imaged image by setting one threshold value with respect to a plurality of imaged images obtained from one sample, and applying the threshold value to each imaged image. [0004] However, since the particles are extracted based on the same threshold value with respect to the plurality of imaged images obtained from one sample in US 2007-0273878, if the imaged image obtained from one sample contains the particle image of large luminance and the particle image of small luminance, the error in extraction of the particle image of small luminance becomes large or may not be extracted if the threshold value is set so as to extract the particle image of large luminance with small error, that is, at high accuracy. Furthermore, if the threshold value is set so as to extract the particle image of small luminance at high accuracy, the error in extraction of the particle image of large luminance becomes large. Therefore, the particle analyzer of US 2007-0273878 has problems in that it is difficult to extract each particle image at small error, that is, at high accuracy over a plurality of particles in the sample. SUMMARY OF THE INVENTION [0005] The scope of the invention is defined solely by the appended claims, and is not affected to any degree by the statements within this summary. [0006] A first aspect of the invention is a particle analyzer comprising a controller, including a memory under control of a processor, the memory storing instructions enabling the processor to carry out operations, comprising: acquiring extraction parameters for each particle based on each image of a particles; extracting particle images from each image of a particles based on the extraction parameters obtained for each particle; and analyzing particles based on the extracted particle image. [0007] A second aspect of the invention is a particle analyzer comprising: an extraction parameter acquiring means for acquiring extraction parameters for each particle based on each image of a particle; an extraction means for extracting particle images from the each image of a particle based on the extraction parameters obtained for each particle by the extraction parameter acquiring means; and an analyzing means for analyzing particles based on the particle image extracted by the extraction means. [0008] A third aspect of the invention is method for analyzing particles comprising steps of: acquiring extraction parameters for each particle based on each image of a particle; extracting particle images from each image of a particle based on the extraction parameters obtained for each particle; and analyzing particles based on the particle images extracted by the extraction means. [0009] A fourth aspect of the invention is a computer program product comprising: a computer readable medium; and instructions, on the computer readable medium, adapted to enable a particle analyzer to perform operations, comprising steps of: acquiring extraction parameters for each particle based on each image of a particle; extracting particle images from each image of a particle based on the extraction parameters obtained for each particle; and analyzing particles based on the particle images extracted by the extraction means. BRIEF DESCRIPTION OF THE DRAWINGS [0010] FIG. 1 is a perspective view showing an overall configuration of a particle analyzer according to a first embodiment of the present invention; [0011] FIG. 2 is a schematic view showing the overall configuration of the particle analyzer shown in FIG. 1 ; [0012] FIG. 3 is a cross-sectional view for describing the flow of particle suspension liquid and sheath liquid in a flow cell of the particle analyzer shown in FIG. 2 ; [0013] FIG. 4 is a plan view showing an internal structure of a particle image processing device of the particle analyzer shown in FIG. 1 ; [0014] FIG. 5 is a plan view partially showing the particle image processing device shown in FIG. 4 ; [0015] FIG. 6 is a front view of the particle image processing device shown in FIG. 5 ; [0016] FIG. 7 is a schematic view for describing the principle of dark-field illumination; [0017] FIG. 8 is a block diagram showing a configuration of the particle image processing device of the particle analyzer shown in FIG. 1 ; [0018] FIG. 9 is a schematic view for describing the image processing operation of the particle analyzer shown in FIG. 1 ; [0019] FIG. 10 is a flowchart showing the processing procedure of the image processing processor of the particle image processing device shown in FIG. 8 ; [0020] FIG. 11 is a schematic view for describing a set value of a coefficient used in the Laplacian filter processing by a Laplacian filter processing circuit of the image processing processor shown in FIG. 8 ; [0021] FIG. 12 is a luminance histogram of a case where bright-field illumination in the binarization processing of the image processing processor shown in FIG. 8 is performed; [0022] FIG. 13 is a luminance histogram of a case where dark-field illumination in the binarization processing of the image processing processor shown in FIG. 8 is performed; [0023] FIG. 14 is a schematic view showing content of a prime code data storage memory used in the prime code/multi-point information acquiring processing by the binarization processing circuit of the image processing processor shown in FIG. 8 ; [0024] FIG. 15 is a schematic view for describing the definition of prime code used in the prime code/multi-point information acquiring processing by the binarization processing circuit of the image processing processor shown in FIG. 8 ; [0025] FIG. 16 is a schematic view for describing the concept of the multi-point used in the prime code/multi-point information acquiring processing by the binarization processing circuit of the image processing processor shown in FIG. 8 ; [0026] FIG. 17 is a schematic view for describing the determination principle on whether or not the inner particle image used in the overlap check processing by the overlap check circuit of the image processing processor shown in FIG. 8 exists; [0027] FIG. 18 is a schematic view showing a configuration of one particle data in one frame data transmitted from the image processing substrate to the image data processing unit shown in FIG. 9 ; [0028] FIG. 19 is a view for describing the rule when cutting out the partial image from the entire image of the particle by the image processing substrate shown in FIG. 9 ; [0029] FIG. 20 is a flowchart showing the operation procedure of an image analysis processing module of the image data processing unit shown in FIG. 9 ; [0030] FIG. 21 is a view showing a Sobel operator when calculating a gradient ΔX in a binarization processing of a image processing processor according to a second embodiment of the present invention; [0031] FIG. 22 is a view showing a Sobel operator when calculating a gradient ΔY in the binarization processing of the image processing processor according to the second embodiment of the present invention; [0032] FIG. 23 is an experiment result of example 1 in a comparative experiment for verifying the effects of the present invention; [0033] FIG. 24 is an experiment result of example 2 in the comparative experiment for verifying the effects of the present invention; and [0034] FIG. 25 is an experiment result of a comparative example in the comparative experiment for verifying the effects of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS [0035] Hereinafter, embodiments of a sample analyzer of the invention will be described in detail with reference to the accompanying drawings. First Embodiment [0036] FIG. 1 is a perspective view showing an overall configuration of a particle analyzer according to a first embodiment of the present invention, and FIG. 2 is a schematic view showing the overall configuration of the particle analyzer shown in FIG. 1 . FIGS. 3 to 6 are views for describing the structure of a particle image processing device of the particle analyzer shown in FIG. 1 , and FIG. 7 is a view for describing the measurement principle of dark-field illumination. FIG. 8 is a block diagram showing a configuration of the particle image processing device of the particle analyzer shown in FIG. 1 . The overall configuration of the particle analyzer according to the first embodiment of the present invention will be described first with reference to FIGS. 1 to 8 . [0037] The particle analyzer is used to manage the quality of fine ceramics particles, and powder such as pigment and cosmetic powder. As shown in FIGS. 1 and 2 , the particle analyzer is configured by a particle image processing device 1 , and an image data analyzing device 2 electrically connected to the particle image processing device 1 by means of an electric signal wire (in the first embodiment, USB (Universal Serial Bus) 2.0 cable) 300. [0038] The particle image processing device 1 is arranged to perform the process of obtaining a still image by imaging the particles in the liquid, and analyzing the obtained still image to acquire morphological feature information (size, shape, and the like) of the particle image contained in the still image. The particles to be analyzed by such particle image processing device 1 include fine ceramic particles, and powder such as pigment and cosmetic powder. As shown in FIG. 1 , the particle image processing device 1 is entirely covered with a cover 1 a. This cover 1 a has a light shielding function, and is attached at the inner surface with a heat insulating material (not shown) to maintain heat. [0039] As shown in FIG. 4 , the particle image processing device 1 is attached with a Peltier element 1 b and a fan 1 c for maintaining the interior covered with the cover 1 a (see FIG. 1 ) of the particle image processing device 1 at a predetermined temperature (about 25° C.). By maintaining the interior of the particle image processing device 1 at the predetermined temperature (about 25°) by the cover 1 a, the Peltier element 1 b, and the fan 1 c, shift in focal length in time of imaging caused by change in temperature, and change in characteristics such as viscosity and specific gravity of the sheath liquid, to be hereinafter described, can be suppressed. [0040] In the particle image processing device 1 according to the first embodiment, switch can be made to either the bright-field illumination or the dark-field illumination depending on the measuring target when imaging the particles. For instance, the particles are imaged at the dark-field illumination if the measuring target is a transparent particle or close-to-transparent particle (translucent particle), and the particles are imaged at the bright-field illumination if the measuring target is an opaque particle. [0041] The image data analyzing device 2 is arranged to automatically calculate and display the morphological feature information such as size and shape of the particles by storing and analyzing the still image processed by the particle image processing device 1 . As shown in FIGS. 1 and 2 , the image data analyzing device 2 comprises a personal computer (PC) including an image display unit (display) 2 a for displaying the still image, and a keyboard 2 c. [0042] As shown in FIG. 2 , the particle image processing device 1 includes a fluid mechanism section 3 for forming a flow of particle suspension liquid; an illumination optical system 4 for irradiating light on the flow of particle suspension liquid; an imaging optical system 5 for imaging the flow of particle suspension liquid; an image processing substrate 6 for performing a cutout process, and the like of a partial image (particle image) from the still image imaged by the imaging optical system 5 ; and a CPU substrate 7 for performing control of the particle image processing device 1 . The illumination optical system 4 and the imaging optical system 5 are arranged at opposing positions with the fluid mechanism section 3 in between. [0043] The fluid mechanism section 3 includes a transparent flow cell 8 made of quartz, a supply mechanism unit 9 for supplying the particle suspension liquid and the sheath liquid to the flow cell 8 , and a support mechanism unit 10 for supporting the flow cell 8 . The flow cell 8 has a function of converting the flow of particle suspension liquid to a flat flow by sandwiching both sides of the particle suspension liquid with the flow of the sheath liquid. As shown in FIGS. 2 and 3 , the flow cell 8 has a vertically long recess 8 a in the vicinity of the central position of the outer surface on the imaging optical system 5 side of the flow cell 8 . The particle suspension liquid flowing through the flow cell 8 is imaged through the recess 8 a of the flow cell 8 . [0044] As shown in FIG. 2 , the supply mechanism unit 9 includes a supply portion 9 b with a sample nozzle 9 a (see FIG. 2 ) for supplying the particle suspension liquid to the flow cell 8 , a supply port 9 c for feeding the particle suspension liquid to the supply portion 9 b, a sheath liquid container 9 d for storing the sheath liquid, a sheath liquid chamber 9 e for temporarily storing the sheath liquid, and a discard chamber 9 f for storing the sheath liquid that has passed the flow cell 8 . [0045] As shown in FIGS. 2 and 4 , the illumination optical system 4 is configured by an irradiation unit 30 , a light reducing unit 40 installed on the flow cell 8 side than the irradiation unit 30 , and a light collecting unit 50 installed on the flow cell 8 side than the light reducing unit 40 . The irradiation unit 30 is arranged to irradiate light towards the flow cell 8 . [0046] As shown in FIGS. 5 and 6 , the irradiation unit 30 includes a lamp 31 serving as a light source, a field stop 32 , and a bracket 33 for supporting the lamp 31 and the field stop 32 . The field stop 32 is arranged to adjust the range of field that can be imaged by an imaging unit 80 . The light emitting voltage of the lamp 31 is controlled by the image data analyzing device 2 . [0047] The lamp 31 periodically irradiates the pulse light at every 1/60 seconds when imaging the particles. Thus, the still images for 60 frames are imaged in one second. In the normal measurement, the still images for 3600 frames are imaged in one minute in one measurement. [0048] The light reducing unit 40 is arranged to adjust the intensity of light by reducing the light from the irradiation unit 30 . As shown in FIG. 5 , the light reducing unit 40 includes a fixed light reducing portion 40 a fixedly attached to the irradiation unit 30 , a movable light reducing portion 40 b movably attached in the Y direction with respect to the irradiation unit 30 , and a bracket 40 c for supporting the fixed light reducing portion 40 a and the movable light reducing portion 40 b. [0049] As shown in FIGS. 5 and 6 , the fixed light reducing portion 40 a includes a fixed light reducing filter 41 , two long screws 42 , a rail member 43 , and a positioning pin 44 . The fixed light reducing filter 41 is detachably configured with respect to the rail member 43 so as to be changeable with another fixed light reducing filter 41 with different light reduction rate. The two long screws 42 are arranged to attach the fixed light reducing filter 41 to the rail member 43 . The positioning pin 44 has a function of positioning the fixed light reducing filter 41 with respect to the rail member 43 . In the first embodiment, the fixed light reducing filter 41 of the fixed light reducing portion 40 a is detached when performing imaging by the dark-field illumination in order to ensure sufficient light quantity in time of imaging by the dark-field illumination. [0050] As shown in FIGS. 5 and 6 , the movable light reducing portion 4 b includes a movable light reducing filter 45 , a drive mechanism unit 47 for moving the movable light reducing filter 45 along a linear movement guide 46 (see FIG. 6 ), a detection piece 48 (see FIG. 5 ) attached to the movable light reducing filter 45 , and a light transmissive sensor 49 , attached to the bracket 40 c, for detecting the detection piece 48 . The movable light reducing filter 45 is installed on the irradiation unit 30 side than the fixed light reducing portion 40 a, and is configured to be movable between an operating position at which the light from the irradiation unit 30 can be reduced and a retreated position at which the light from the irradiation unit 30 is not influenced. The drive mechanism unit 47 includes an air cylinder 47 b, serving as a drive source, with a piston rod 47 a, and a drive transmission member 47 d connected to the piston rod 47 a of the air cylinder 47 b by way of a coupling member 47 c. The drive transmission member 47 d is attached to the movable light reducing filter 45 . The movable light reducing filter 45 is attached so as not to be easily changed with another movable light reducing filter 45 of different light reduction rate, as opposed to the fixed light reducing filter 41 . The movable light reducing filter 45 is used to adjust the light quantity in magnification switching by a relay lens (lens 88 and lens 89 ), to be hereinafter described. [0051] The light collecting unit 50 is arranged to collect the light reduced by the light reducing unit 40 towards the flow cell 8 . As shown in FIGS. 5 and 6 , the light collecting unit 50 includes an auxiliary lens 51 , an aperture stop 52 installed on the flow cell 8 (see FIG. 6 ) side than the auxiliary lens 51 , a capacitor lens 53 installed on the flow cell 8 side than the aperture stop 52 , a stop adjuster 54 for adjusting the numerical aperture of the aperture stop 52 , and a bracket 55 . The aperture stop 52 is arranged to adjust the quantity of light from the irradiation unit 30 side. When performing the dark-field illumination, the aperture of the aperture stop 52 is set to be a maximum by the stop adjuster 54 . [0052] As shown in FIG. 7 , in the first embodiment, a ring slit 150 having a light shielding portion 150 a at the central part is attached to the auxiliary lens 51 when performing the dark-field illumination. This can prevent the light irradiated from the lamp 31 from directly entering an objective lens 61 . The light shielding portion 150 a of the ring slit 150 is set with a minimum size the light does not directly enter the objective lens 61 . The opening portion (slit portion) thus becomes large, and the light of a quantity necessary for imaging can be irradiated on the particles. [0053] The measurement principle of the dark-field illumination will now be described. As shown in FIG. 7 , in the dark-field illumination, the light collected by the capacitor lens 53 is prevented from directly entering the objective lens 61 by attaching the ring slit 150 to the auxiliary lens 51 . In other words, in the dark-field illumination, only the light diffracted by impacting the sample (particle) 160 enters the objective lens 61 , thereby forming a sample image (particle image). The light that does not impact the sample (particle) 160 does not enter the objective lens 61 , and thus the background appears dark (has small luminance value) compared to the sample image (particle image). When imaging a transparent particle or a translucent particle, the dark-field illumination is preferably used since the difference in luminance value between the background and the particle image of the imaged image in the dark-field illumination becomes larger than the difference in luminance value between the background and the particle image of the imaged image in the bright-field illumination. [0054] In the bright-field illumination, the ring slit 150 (see FIG. 7 ) is detached so that the light shielded by impacting the sample (particle) does not enter the objective lens 61 or enters the objective lens with weakened intensity. The light that does not impact the sample (particle) directly enters the objective lens 61 . Therefore, in the bright-field illumination, the background of the imaged image appears brighter (has large luminance value) than the sample image (particle image). [0055] As shown in FIGS. 2 and 4 , the imaging optical system 5 is configured by an objective lens unit 60 , an imaging lens unit 70 , and an imaging unit 80 . [0056] The objective lens unit 60 is arranged to enlarge the light image of the particles in the particle suspension liquid flowing through the flow cell 8 (see FIG. 6 ) irradiated with light from the illumination optical system 4 . As shown in FIGS. 5 and 6 , the objective lens unit 60 includes the objective lens 61 , an objective lens holder 62 for holding the objective lens 61 , a bracket 63 for supporting the objective lens holder 62 , a positioning pin 64 (see FIG. 5 ), and a fixing screw 65 . [0057] As shown in FIG. 4 , the imaging lens unit 70 includes an imaging lens 71 for imaging the light image of the particles enlarged by the objective lens unit 60 , and a bracket 72 for holding the imaging lens 71 . [0058] The imaging unit 80 is arranged to image the particle image imaged by the imaging lens unit 70 . As shown in FIG. 4 , the imaging unit 80 includes a relay lens box 81 , a CCD camera 82 , a drive mechanism unit 84 for sliding the relay lens box 82 in a P direction of FIG. 4 along two linear movement guides 83 , a light shielding cover 85 for covering the imaging unit 80 , a detection piece 86 attached to the relay lens box 81 , and a light transmissive sensor 87 for detecting the detection piece 86 . A lens 88 having an enlargement magnification of two times and a lens 89 having an enlargement magnification of 0.5 times are built in the relay lens box 81 . The lens 88 having an enlargement magnification of two times and the lens 89 having an enlargement magnification of 0.5 times are interchanged by sliding the relay lens box 81 in the P direction. [0059] The configuration of the image processing substrate 6 will now be described with reference to FIGS. 2 and 8 . As shown in FIG. 8 , the image processing substrate 6 is configured by a CPU 91 , a ROM 92 , a main memory 93 , an image processing processor 94 , a frame buffer 95 , a filter test memory 96 , a background correction data memory 97 , a prime code data storage memory 98 , a vertex data storage memory 99 , a result data storage memory 100 , an image input interface 101 , and a USB interface 102 . The CPU 91 , the ROM 92 , the main memory 93 , and the image processing processor 94 are connected by a bus so that data can be transmitted and received with each other. The image processing processor 94 is connected to the frame buffer 95 , the filter test memory 96 , the background correction data memory 97 , the prime code data storage memory 98 , the vertex data storage memory 99 , the result data storage memory 100 , and the image input interface 101 by an individual bus. Read and write of data from the image processing processor 94 to the frame buffer 95 , the filter test memory 96 , the background correction data memory 97 , the prime code data storage memory 98 , the vertex data storage memory 99 , and the result data storage memory 100 thus become possible, and input of data from the image input interface 101 to the image processing processor 94 becomes possible. The CPU 91 of such image processing substrate 6 is connected to the USB interface 102 by way of a PCI bus. The USB interface 102 is connected to the CPU substrate 7 by way of a USB/RS-232c converter (not shown). [0060] The CPU 91 has a function of executing computer programs stored in the ROM 92 , and computer programs loaded in the main memory 93 . The ROM 92 is configured by a mask ROM, PROM, EPROM, EEPROM, and the like. The ROM 92 is recorded with computer programs to be executed by the CPU 51 a, data used for the computer programs, and the like. The main memory 93 is configured by SRAM or DRAM. The main memory 93 is used to read out the computer program recorded on the ROM 92 , and is used as a work region of the CPU 91 when the CPU 91 executes the computer program. [0061] The image processing processor 94 is configured by FPGA (Field Programmable Gate Array), ASIC (Application Specific Integrated Circuit), and the like. The image processing processor 94 is a processor dedicated to image processing including hardware capable of executing image processing such as median filter processing circuit, Laplacian filter processing circuit, binarization processing circuit, edge trace processing circuit, overlap check processing circuit, and result data creating circuit. The frame buffer 95 , the filter test memory 96 , the background correction data memory 97 , the prime code data storage memory 98 , the vertex data storage memory 99 , and the result data storage memory 100 are respectively configured by SRAM, DRAM, or the like. Such frame buffer 95 , the filter test memory 96 , the background correction data memory 97 , the prime code data storage memory 98 , the vertex data storage memory 99 , and the result data storage memory 100 are used for storing data when the image processing processor 94 executes image processing. [0062] The image input interface 101 includes a video digitize circuit (not shown) including an A/D converter. As shown in FIGS. 2 and 8 , the image input interface 101 is electrically connected to a CCD camera 82 (imaging unit 80 ) by a video signal cable 103 . The video signal input from the CCD camera 82 is A/D converted by the image input interface 101 (see FIG. 8 ). The digitized image data of the still image is stored in the frame buffer 95 . The USB interface 102 is connected to the CPU substrate 7 by way of the USB/RS-232c converter (not shown). The USB interface 102 is connected to the image data analyzing device 2 by the electrical signal wire (USB 2.0 cable) 300. The CPU substrate 7 is configured by CPU, ROM, RAM, and the like, and has a function of controlling the particle image processing device 1 . [0063] As shown in FIGS. 1 and 2 , the image data analyzing device 2 is configured by a personal computer (PC) including an image display unit 2 a, an image data processing unit 2 b serving as a device body equipped with CPU, ROM, RAM, hard disc, and the like, and an input device 2 c such as keyboard. The hard disc of the image data processing unit 2 b is installed with an application program for performing analysis processing and statistical processing of the image data based on the processing result in the particle image processing device 1 by communicating with the particle image processing device 1 . The application program is configured to be executed by the CPU of the image data processing unit 2 b. [0064] The operation of the particle image processing device 1 according to the first embodiment of the present invention will be described below with reference to FIGS. 2 , 3 , 4 , 8 , and 9 . [0065] First, after performing focus adjustment of the imaging optical system 5 , adjustment of strobe light emission intensity of the lamp 31 is performed. Thereafter, imaging of a background correction image for generating background correction data is performed. Specifically, the lamp 31 periodically irradiates the pulse light every 1/60 seconds and the CCD camera 82 performs imaging with only the sheath liquid supplied to the flow cell 8 . The still image (background correction image) for every 1/60 seconds in a state the particles are not passing through the flow cell 8 is imaged by the CCD camera 82 through the objective lens 61 . A plurality of background correction images without the particles is retrieved to the image processing substrate 6 . One background correction data is thereby generated, as shown in FIG. 9 . In the image processing substrate 6 , the background correction data is stored in the background correction data memory 97 (see FIG. 8 ), and transmitted to the image data processing unit 2 b of the image data analyzing device 2 through the electrical signal wire (USB 2.0 cable) 300. On the image data analyzing device 2 side, the received background correction data is saved in a memory of the image data processing unit 2 b. The process of generating the background correction data is executed only once before the start of imaging of the particles. [0066] The particles are then imaged. Specifically, the particle suspension liquid supplied to the supply port 9 c shown in FIG. 2 is sent to the supply portion 9 b positioned on the upper side of the flow cell 8 . The particle suspension liquid of the supply portion 9 b is gradually pushed out into the flow cell 8 from the distal end of the sample nozzle 9 a (see FIG. 2 ) arranged in the supply portion 9 b. The sheath liquid is also sent into the flow cell 8 from the sheath liquid container 9 d through the sheath liquid chamber 9 e and the supply portion 9 b. As shown in FIG. 3 , the particle suspension liquid flows from the upper side to the lower side in the flow cell 8 while being squeezed to a hydrodynamic flat shape by being sandwiched with the sheath liquid from both sides. As shown in FIG. 2 , the particle suspension liquid is discharged through the discard chamber 9 f after passing through the flow cell 8 . As described above, the image of the particles is imaged by the imaging unit 80 through the objective lens unit 60 in the imaging optical system 5 by irradiating light from the irradiation unit 30 of the illumination optical system 4 onto the flow of the particle suspension liquid squeezed to a flat shape in the flow cell 8 of the fluid mechanism section 3 . [0067] In this case, the lamp 31 (see FIG. 4 ) periodically irradiates the pulse light every 1/60 on the flow of the particle suspension liquid squeezed flat in the flow cell 8 . The irradiation of pulse light from the lamp 31 is performed for 60 seconds. A total of 3600 still images are imaged by the CCD camera 82 through the objective lens 61 . [0068] The distance between the center of gravity of the particle to be imaged and the imaging surface of the CCD camera 82 of the imaging unit 80 can be made substantially constant by imaging the flat plane of the flow of particle suspension liquid with the imaging unit 80 . Thus, a still image focused on the particle is always obtained irrespective of the size of the particle. [0069] The still image imaged by the CCD camera 82 is output to the image processing substrate 6 (see FIG. 8 ) as a video signal via the video signal cable 103 . In the image input interface 101 of the image processing substrate 6 , the digitized image data is generated from the imaged image by performing A/D conversion on the video signal from the CCD camera 82 (see FIG. 8 ). The image data is a gray scale image. The image data output by the image input interface 101 shown in FIG. 8 is transferred and stored in the frame buffer 95 (series of image data to be stored in the frame buffer 95 is referred to as frame data). As shown in FIG. 9 , the cutout process (extraction) from the imaged image including a plurality of particles to a partial image including a single particle by the image processing substrate 6 , and the transmission of the image processing result data to the image data processing unit 2 b are performed on the frame data stored in the frame buffer 95 . In this case, the following image processing by the image processing processor 94 (see FIG. 8 ) of the image processing substrate 6 is first executed. [0070] FIG. 10 is a flowchart showing a processing procedure of the still image of the image processing processor of the particle image processing device according to the first embodiment shown in FIG. 8 . FIGS. 11 to 19 are views for describing the processing method of the still image of the image processing processor of the particle image processing device according to the first embodiment shown in FIG. 8 . The processing method of the still image of the image processing processor 94 of the particle image processing device 1 according to the first embodiment will be described below with reference to FIGS. 8 to 19 . [0071] As for the image processing by the image processing processor 94 , the image processing processor 94 executes noise removal processing on the still image (image data) stored in the frame buffer 95 in step S 1 . That is, the image processing processor 94 is arranged with a median filter processing circuit, as mentioned above. Through the median filter processing by the median filter processing circuit, noise such as dust in the still image is removed. The median filter processing is a process, with respect to a total of nine pixels including the pixel of interest and the eight pixels at the vicinity thereof, of lining each luminance value in order of large (or small) numbers and setting a median (intermediate value) of the pixel values of nine pixels as a luminance value of the pixel of interest. [0072] In step S 2 , the image processing processor 94 executes a background correction process for correcting intensity variation of the irradiation light on the flow of particle suspension liquid. That is, the image processing processor 94 is arranged with a Laplacian filter processing circuit, as mentioned above. In the background correction process, a comparison calculation between the background correction data acquired in advance and stored in the background correction data memory 97 and the still image after the median filter processing is performed by the Laplacian filter processing circuit, and the majority of the background image is removed from the still image. [0073] In step S 3 , the image processing processor 94 executes an edge enhancement process. In the edge enhancement process, the Laplacian filter processing is performed by the Laplacian filter processing circuit. The Laplacian filter processing is a process, with respect to a total of nine pixels including the pixel of interest and the eight pixels at the vicinity thereof, multiplying each luminance value and a corresponding predetermined coefficient, and setting the sum of the multiplication result as the luminance value of the pixel of interest. As shown in FIG. 11 , assume the coefficient corresponding to the pixel of interest X(i, j) is “2”, and the coefficient corresponding to four pixels (i, j−1), X(i, j+1), X(i−1, j), and X(i+1, j) adjacent with the pixel of interest in the up and down and left and right directions is “−¼”, and the coefficient corresponding to four pixels X(i−1, j−1), X(i+1, j−1), X(i+1, j+1), and X(i−1, j+1) adjacent with the pixel of interest in the diagonal direction is “0”. The luminance value Y(i, j) of the pixel of interest after the Laplacian filter processing is calculated from the following equation (1). Here, 255 is output if the result of the calculation by the following equation (1) is greater than 255, and 0 is output if the result of the calculation by equation (1) is a negative number. [0000] Y ( i, j )=2 ×X ( i, j )−0.25×( X ( i, j− 1)+ X ( i− 1, j )+ X ( i, j+ 1)+ X ( i+ 1, j ))+0.5   (1) [0074] In step S 4 , the image processing processor 94 sets a binarization threshold value based on the data after the edge enhancement process has been performed. In other words, the Laplacian filter circuit of the image processing processor 94 is arranged with a luminance histogram portion executing the binarization threshold value setting processing. First, the image processing processor 94 creates a luminance histogram (see FIGS. 12 and 13 ) from the image data after the Laplacian filter processing. FIG. 12 shows the luminance histogram of the still image by the bright-field illumination, and FIG. 13 shows the luminance histogram of the still image by the dark-field illumination. The image processing processor 94 performs a predetermined smoothing processing on the luminance histogram. With respect to the still image by the bright-field illumination, the most frequent luminance value of the still image is obtained from the luminance histogram after the smoothing processing, and thereafter, the binarization threshold value is calculated by the following equation (2) by using the most frequent luminance value. [0000] Binarization threshold value=most frequent luminance value of still image×α(0<α<1)+β  (2) [0075] In equation (2), α and β are variables that can be set by the user, and the user can change the values of α and β depending on the measuring target. The default value of α and β is “0.9” and “0”, respectively. [0076] In the first embodiment, the binarization threshold value is calculated as below with respect to the still image by the dark-field illumination. First, the most frequent luminance value is obtained from the luminance histogram after the smoothing processing. The maximum luminance value of the still image is determined by referencing the luminance values of all pixels of the still image. The binarization threshold value is calculated by the following equations (3) and (4) by using the most frequent luminance value and the maximum luminance value of the still image. [0000] Binarization threshold value=most frequent luminance value of still image+maximum luminance value of still image×γ(0<γ<1)   (3) [0000] Binarization threshold value=most frequent luminance value of still image+δ  (4) [0077] Equation (3) is applied in the case of maximum luminance value of still image×γ>δ, and equation (4) is applied in the case of maximum luminance value of still image×γ≦δ. That is, the binarization threshold value is essentially calculated from equation (3), but if the calculation value of equation (3) becomes smaller than the calculation value of equation (4) as the particle image of the still image is dark, the calculation value of the equation (4) is set as the binarization threshold value. In equations (3) and (4), γ and δ are variables that can be set by the user, and the user can change the values of γ and δ depending on the measuring target. The threshold value for extracting the particles can be calculated in accordance with the luminance (brightness) of each particle by calculating the binarization threshold value by equation (3). [0078] In step S 5 , the image processing processor 94 performs a binarization processing on the still image after the Laplacian filter processing at the threshold level (binarization threshold value) set in the binarization threshold value setting processing. That is, a collection of pixels having a luminance value smaller than the value calculated in equation (2) is specified as a particle image with respect to the still image by the bright-field illumination. A collection of pixels having a luminance value greater than the value calculated in equation (3) or equation (4) is specified as a particle image with respect to the still image by the dark-field illumination. [0079] In step S 6 , the prime code and multi-point information are acquired with respect to each pixel of the image performed with the binarization processing. That is, the image processing processor 94 is arranged with a binarization processing circuit. The binarization processing and the prime code/multi-point information acquiring processing are executed by the binarization processing circuit. The prime code is a binarization code obtained for a total of nine pixels including the pixel of interest and the eight pixels at the vicinity thereof, and is defined as below. As shown in FIG. 14 , the prime code data storage memory 98 includes two regions, a prime code storage region 98 a and a multi-point number storage region 98 b, in one word (eleven bits). The prime code storage region 98 a is a region of eight bits indicated by bit 0 to bit 7 in FIG. 14 , and the multi-point number storage region 98 b is a region of three bits indicated by bit 8 to bit 10 in FIG. 14 . The definition of the prime code will now be described. As shown in FIG. 15 , the pixel values of P 1 to P 3 are 0, and the pixel values of P 0 and P 4 to P 8 are 1 with respect to the nine pixels of P 0 to P 8 of the binarization processed image data. The pixel values of P 0 to P 8 become 1 when the luminance value respectively corresponding to the nine pixels of P 0 to P 8 is greater than or equal to the binarization threshold value, and the pixel values of P 0 to P 8 become 0 when the luminance value respectively corresponding to the nine pixels of P 0 to P 8 is smaller than the binarization threshold value. The prime code in this case will be described. The eight pixels P 0 to P 7 other than the pixel of interest P 8 each corresponds to bit 0 to bit 7 of the prime code storage region 98 a. That is, the prime code storage region 98 a is configured so that the pixel values of the eight pixels P 0 to P 7 are respectively stored from the lower order bit (bit 0 ) towards the higher order bit (bit 7 ). The prime code is thus 11110001 in binary number representation, and is F 1 in hexadecimal number representation. The pixel value of the pixel of interest P 8 is not included in the prime code. [0080] If the region configured by the pixel of interest and the eight pixels at the vicinity thereof is part of the boundary of the particle image, that is, if the prime code is other than 00000000 in binary number representation, the multi-point information is obtained. The multi-point is the code indicating the number of times it may be passed in edge trace, to be hereinafter described, and the multi-point information corresponding to all patterns are stored in the lookup table (not shown) in advance. The number of multi-points is obtained by referencing the lookup table. With reference to FIG. 16 , if the pixel values of the four pixels of P 2 and P 5 to P 8 are one, and the pixel values of four pixels of P 0 , P 1 , and P 3 are 0, the pixel of interest P 8 has a possibility of being passed twice in edge trace, as shown with arrows C and D in FIG. 16 . Therefore, the pixel of interest P 8 is a dual point, and the number of multi-points is two. The number of multi-points is stored in the multi-point number storage region 98 b. [0081] In step S 7 , the image processing processor 94 creates vertex data. The vertex data creating process is also executed by the binarization processing circuit arranged in the image processing processor 94 , similar to the binarization processing and the prime code/multi-point information acquiring processing, as mentioned above. The vertex data is the data indicating the coordinate scheduled to start the edge trace, to be hereinafter described. The region of a total of nine pixels including the pixel of interest and the eight pixels at the vicinity thereof are judged as the vertex only when the following three conditions (condition (1) to condition (3)) are all met. [0082] Condition (1) . . . Pixel value of pixel of interest P 8 is one. [0083] Condition (2) . . . Pixel values of the three pixels (P 1 to P 3 ) on the upper side of the pixel of interest P 8 and one pixel (P 4 ) on the left of the pixel of interest P 8 are zero. [0084] Condition (3) . . . Pixel values of one pixel (P 0 ) on the right of the pixel of interest P 8 , and at least one of the three pixels (P 5 to P 7 ) on the lower side of the pixel of interest P 8 are one. [0085] The image processing processor 94 searches for the pixel corresponding to the vertex from all the pixels, and stores the created vertex data (coordinate data indicating the position of the vertex) in the vertex data storage memory 99 . [0086] In step S 8 , the image processing processor 94 executes the edge trace processing. The image processing processor 94 is arranged with an edge trace processing circuit, and the edge trace processing is executed by the edge trace processing circuit. In the edge trace processing, the coordinate to start the edge trace is first specified from the vertex, and the edge trace of the particle image is performed from the coordinate based on the prime code and the code for determining the advancing direction stored in advance. The image processing processor 94 calculates the area value, the number of straight counts, the number of oblique counts, the number of corner counts, and the position of each particle image in edge trace. The area value of the particle image is the total number of pixels configuring the particle image, that is, the total number of pixels contained on the inner side of the region surrounded by edges. The number of straight counts is the total number of edge pixels excluding the edge pixels at both ends of a linear zone when the edge pixels of three or more pixels of the particle image are linearly lined in the up and down direction or the left and right direction. In other words, the number of straight counts is the total number of edge pixels configuring a linear component extending in the up and down direction or the left and right direction of the edges of the particle image. The number of oblique counts is the total number of edge pixels excluding the edge pixels at both ends of a linear zone in the oblique direction when the edge pixels of three or more pixels of the particle image are linearly lined in the oblique direction. In other words, the number of oblique counts is the total number of edge pixels configuring the linear component extending in the oblique direction of the edges of the particle image. The number of corner counts is the total number of edge pixels where a plurality of adjacent edge pixels contact in different directions (e.g., when adjacent to one edge pixel at the upper side and adjacent to the other edge pixel at the left side) of the edge pixels of the particle image. In other words, the number of corner counts is the total number of edge pixels configuring the corner of the edges of the particle image. The position of the particle image is determined by the coordinates of the right end, the left end, the upper end, and the lower end of the particle image. The image processing processor 94 stores the data of the calculation result in an internal memory (not shown) incorporated in the image processing processor 94 . [0087] In step S 9 , the image processing processor 94 executes the overlap check processing of the particles. The image processing processor 94 is arranged with an overlap check circuit, and the overlap check processing is executed by the overlap check circuit. In the overlap check processing of the particles, the image processing processor 94 first determines whether or not another particle image (inner particle image) is contained in one particle image (outer particle image) based on the analysis result of the particle image by the edge trace processing. If the inner particle image exists in the outer particle image, the inner particle image is excluded from the cutout target of the partial image in the result data creating processing to be hereinafter described. The determination principle on whether or not the inner particle image exists will now be described. First, as shown in FIG. 17 , two particle images G 1 and G 2 are selected, and the maximum value G 1 XMAX and the minimum value G 1 XMIN of the X coordinate and the maximum value G 1 YMAX and the minimum value G 1 YMIN of the Y coordinate of the particle image G 1 are specified. The maximum value G 2 XMAX and the minimum value G 2 XMIN of the X coordinate and the maximum value G 2 YMAX and the minimum value G 2 YMIN of the Y coordinate of the particle image G 2 are specified. The particle image G 1 is determined as including the particle image G 2 and the inner particle image is determined as existing when the following four conditions (condition (4) to condition (7)) are met. [0088] Condition (4) . . . Maximum value G 1 XMAX of the X coordinate of the particle image G 1 is greater than the maximum value G 2 XMAX of the X coordinate of the particle image G 2 . [0089] Condition (5) . . . Minimum value G 1 XMIN of the X coordinate of the particle image G 1 is smaller than the minimum value G 2 XMIN of the X coordinate of the particle image G 2 . [0090] Condition (6) . . . Maximum value G 1 YMAX of the Y coordinate of the particle image G 1 is greater than the maximum value G 2 YMAX of the Y coordinate of the particle image G 2 . [0091] Condition (7) . . . Minimum value G 1 YMIN of the Y coordinate of the particle image G 1 is smaller than the minimum value G 2 YMIN of the Y coordinate of the particle image G 2 . [0092] The result data of the overlap check processing is stored in the internal memory (not shown) of the image processing processor 94 . [0093] In step S 10 , the image processing processor 94 cutouts a partial image (see FIG. 18 ) individually including an individual particle image specified by the processing in steps S 1 to S 9 from the still image, and creates the image processing result data. The cutout of the partial image is performed based on the still image stored in the frame buffer 95 , that is, the still image before binarization, and thus the partial image is the gray scale image. As shown in FIG. 18 , the partial image is the image in which the rectangular region including one particle image and the region of the periphery of the particle image determined by the margin value set in advance is cutout from the still image. The rectangular region refers to a region R 2 wider by three pixels each in the up and down, and left and right directions than a region R 1 determined by the coordinate (YMIN) of the upper end, the coordinate (YMAX) of the lower end, the coordinate (XMIN) of the left end, and the coordinate (XMAX) of the right end of the particle image shown in FIG. 18 . [0094] The image processing processor 94 is arranged with a result data creating circuit, and the result data creating circuit creates the result data based on the cutout partial image, as mentioned above. As shown in FIG. 19 , the image processing result data includes, in addition to the image data of the partial image for all the particle images specified by the image processing in step S 10 as mentioned above, and the data such as the area value (number of pixels), the number of straight counts, the number of oblique counts, and the number of corner counts of the particle image, the data (XMIN, XMAX, TMIN, and YMAX) of the position of the partial image including the particle image, and the data of the storage position of the image data. The image processing result data is generated for every one frame. The size of the image processing result data (one frame data) of one frame is a fixed length of 64 kilobytes. Thus, the size of one frame data does not change by the size of one image processing result data (one particle data) created for one partial image. One frame data is generated by being overwritten on the previous frame data. In one frame data shown in FIG. 19 , each one particle data is very large, and thus only four particle data are embedded. When the one particle data length is small, or the number of particle data is small, the previous frame data may remain at the end of the one frame data since the data is embedded from the head of the one frame data. However, in the image data processing unit 2 b of the transfer destination, one particle data in one frame data is recognized by the total number of particles in one frame stored in the one particle data, and thus the previous frame data remaining at the end will not be recognized. The image processing processor 94 stores the image processing result data created by the result data creating process in the result data storage memory 100 . The image processing by the image processing processor 94 is terminated. The image processing processor 94 repeatedly executes a series of the above image processing by the pipeline processing, and performs the cutout of the partial image for every one frame and the generation of the image processing result data for 3600 frames. If the particle image does not exist in one frame, the head data of the one particle data in one frame shown in FIG. 19 is overwritten, and the particle information between the header and the footer is filled with “0”. [0095] FIG. 20 is a flowchart showing the operation procedures of the image analysis processing module of the image data processing unit according to the first embodiment shown in FIG. 9 . The operation of the analysis processing of the partial image by the image data processing unit 2 b of the image data processing device 2 will now be described with reference to FIG. 20 . [0096] As described above, the application program (image analysis processing module) for performing the analysis processing of the partial image is installed in the hard disc of the image data processing unit 2 b. The analysis processing of the partial image by the image analysis processing module is executed. In the analysis processing operation of the partial image, the image data processing unit 2 b first receives the image processing result data (include partial image) for one frame in step S 21 shown in FIG. 20 . The number of particles in the received image processing result data for one frame is acquired in step S 22 . [0097] In step S 23 , the image data processing unit 2 b extracts the partial image contained in the image processing result data for one frame based on the image data storage position. The image data processing unit 2 b then executes the noise removal processing and the background correction processing in steps S 24 and S 25 for each extracted partial image. The processing of steps S 24 and S 25 are similar to steps S 1 and S 2 in the processing procedure flow of the image processing processor 94 shown in FIG. 10 , and thus detailed description will be omitted. [0098] The image data processing unit 2 b then executes the binarization threshold value setting processing on the partial image executed with each processing of step S 24 and step S 25 . First, the image data processing unit 2 b creates a luminance histogram (see FIGS. 12 and 13 ) from the partial image after the background correction processing. The image data processing unit 2 b performs a predetermined smoothing processing on the luminance histogram. With regards to the partial image by the bright-field illumination, the most frequent luminance value of the partial image is obtained from the luminance histogram after the smoothing processing, and thereafter, the binarization threshold value is calculated by the following equation (5) by using the most frequent luminance value. [0000] Binarization threshold value=most frequent luminance value of partial image×α(0<α<1)+β  (5) [0099] In equation (5), α and β are variables that can be set by the user, and the user can change the values of α and β depending on the measuring target. The default values of α and β are “0.9” and “0”, respectively. [0100] In the first embodiment, the binarization threshold value is calculated as below for the partial image by the dark-field illumination. In other words, the most frequent luminance value is first obtained from the luminance histogram after the smoothing processing. The maximum luminance value of the partial image is obtained by referencing the luminance values of all the pixels of the partial image. The binarization threshold value is calculated by the following equations (6) and (7) by using the most frequent luminance value of the partial image and the maximum luminance value of the partial image. [0000] Binarization threshold value=most frequent luminance value of partial image+maximum luminance value of partial image×γ(0<γ<1)   (6) [0000] Binarization threshold value=most frequent luminance value of partial image+δ  (7) [0101] Equation (6) is applied in the case of maximum luminance value of partial image×γ>δ, and equation (7) is applied in the case of maximum luminance value of partial image×γ≦δ. That is, the binarization threshold value is essentially calculated from equation (6), if the calculation value of equation (6) becomes smaller than the calculation value of equation (7) as the particle image of the partial image is dark, the calculation value of the equation (7) is set as the binarization threshold value. In equations (6) and (7), γ and δ are variables that can be set by the user, and the user can change the values of γ and δ depending on the measuring target. The threshold value for extracting the particles can be calculated in accordance with the luminance (brightness) of each particle by calculating the binarization threshold value by equation (6). [0102] In step S 5 , the image data processing unit 2 b performs the binarization processing on the partial image after the background correction processing at the threshold level (binarization threshold value) set in the binarization threshold value setting processing. That is, a collection of pixels having a luminance value smaller than the value calculated in equation (5) is extracted as a particle image with respect to the partial image by the bright-field illumination. A collection of pixels having a luminance value greater than the value calculated in equation (6) or equation (7) is extracted as a particle image with respect to the partial image by the dark-field illumination. [0103] In step S 28 , the image data processing unit 2 b executes the edge trace processing on the partial image of after the binarization processing. The edge trace processing is similar to step S 8 in the processing procedure flow of the image processing processor 94 shown in FIG. 10 , and thus detailed description will be omitted. [0104] In step S 29 , the image data processing unit 2 b generates morphological feature information of the particle based on the particle image contained in the partial image after the edge trace processing. The morphological feature information specifically includes circle equivalent diameter or degree of circularity. The circle equivalent diameter refers to the diameter of the circle having the same area as the projecting area of the particle image. The degree of circularity is a value indicating how much the shape of the particle image is close to a perfect circle, and is closer to a perfect circle the more the value of the degree of circularity is closer to one. The morphological feature information is generated for every extracted particle image, and the generated morphological feature information is stored in the storage device (not shown) in the image data analyzing device 2 . [0105] In step S 30 , whether or not all the partial images for one frame are performed with the analysis processing is judged. If judged that all the partial images for one frame are not performed with the analysis processing in step S 30 , the process returns to step S 23 , and another partial image is extracted from the image processing result data for one frame based on the image data storage position (see FIG. 19 ). If judged that all the partial images for one frame are performed with the analysis processing in step S 30 , the process proceeds to step S 31 . In step S 31 , whether or not the image processing result data is received for all (3600) frames is judged. If judged that the image processing result data is not received for all frames in step S 31 , the process returns to step S 21 , and the image processing result data for another frame is received. If judged that the image processing result data is received for all frames in step S 31 , the process is terminated. The image analysis processing of the partial images for 3600 frames obtained by imaging of particles for 60 seconds is then terminated. [0106] In the first embodiment, the binarization threshold value is set for every partial image by equation (5). Thus, the threshold value for extracting the particle can be calculated for every particle, and if the imaged image obtained from one sample includes a particle image of large luminance and a particle image of small luminance, the threshold values suited for such particle images can be respectively set. Since the particle image having different luminance can be extracted based on the threshold value set for every particle, the particle images of both the particle image of large luminance and the particle image of small luminance can be extracted at high accuracy. [0107] In the first embodiment, if the particle contained in the sample is transparent or translucent as a result of performing the dark-field illumination on the particle, a clear particle image can be obtained compared to the case of performing the bright-field illumination. [0108] In the first embodiment, the binarization threshold value is calculated by equation (5). The most frequent luminance value in the partial image corresponds to the luminance value of the background in the partial image, and thus the portion of the partial image having a luminance larger than the luminance value of the background by a predetermined luminance value (maximum luminance value in partial image×γ) corresponding to the luminance of the particle can be extracted as the particle image. [0109] In the first embodiment, with respect to the partial image obtained by the dark-field illumination, the particle image is extracted from the imaged image with the value calculated by equation (7) as the binarization threshold value if the value calculated by equation (6) is smaller than the value calculated by equation (7). According to such configuration, if the threshold value calculated by equation (6) becomes too small as the luminance of the particle image is small, the particle image can be extracted with the minimum threshold value calculated by equation (7) as the threshold value. Thus, the particle image can be extracted at high accuracy even if the value calculated by equation (6) becomes too small. [0110] In the first embodiment, the morphological feature information of the particle can be generated based on the particle image extracted at high accuracy by generating the morphological feature information indicating the morphological feature of the particle based on the particle image extracted by the binarization threshold value set for every particle, and thus a more accurate morphological feature information can be generated. Second Embodiment [0111] FIGS. 21 and 22 are views for describing a calculation method of a binarization threshold value of a particle analyzer according to a second embodiment of the present invention. In the second embodiment, an example of calculating the binarization threshold value based on the maximum value of the luminance gradient of the partial image will be described, as opposed to the first embodiment. The configuration other than the calculation method of the binarization threshold value is similar to the first embodiment, and thus the description will be omitted. [0112] In the second embodiment, the binarization threshold value is set as below in the binarization threshold value setting processing of step S 4 (see FIG. 10 ) and step S 26 (see FIG. 20 ) of the first embodiment. The case of the bright-field illumination is similar to the first embodiment, and thus only the case of the dark-field illumination will be described. [0113] First, the image data processing unit 2 b creates a luminance histogram (see FIGS. 12 and 13 ) from the partial image after the background correction processing, and performs a predetermined smoothing processing on the luminance histogram. The most frequent luminance value is obtained from the luminance histogram after the smoothing processing. In the second embodiment, the luminance change (gradient of luminance value) in the pixel is obtained for all the pixels of the partial image. Specifically, the sum of the gradient AX of the luminance value in the X direction (horizontal axis direction) and the gradient ΔY of the luminance value in the Y direction (vertical axis direction) in the partial image of the pixel of interest is set as the gradient of the luminance value of the pixel of interest. Such gradients are calculated by Sobel operator shown in FIGS. 21 and 22 . With respect to the gradient ΔX in the X direction (horizontal axis direction) of the pixel of interest, weighting as shown in FIG. 21 is carried out on the pixel of interest and the eight pixels at the periphery of the pixel of interest, and it is calculated as the sum of the luminance values of each weighted pixel. Therefore, the gradient ΔX of the luminance value in the X direction (horizontal axis direction) in the pixel of interest is calculated by the following equation (8) with the luminance value of the pixel of interest (i, j) as Y(i, j). [0000] Δ X ( i, j )=0 ×Y ( i, j )+0 ×Y ( i, j− 1)+0 ×Y ( i, j+ 1)+2 ×Y ( i− 1, j )+1 ×Y ( i− 1, j+ 1)+1 ×Y ( i− 1, j− 1)−2 ×Y ( i+ 1, j )−1 ×Y ( i+ 1, j+ 1)−1 ×Y ( i+ 1, j− 1)   (8) [0114] Similarly, ΔY in the pixel of interest is calculated by the following equation (9) with the luminance value of the pixel of interest (i, j) as Y(i, j). [0000] Δ Y ( i, j )=0 ×Y ( i, j )−2 ×Y ( i, j− 1)+2 ×Y ( i, j+ 1)+0 ×Y ( i− 1, j )+1 ×Y ( i− 1, j+ 1)−1 ×Y ( i− 1, j− 1)+0 ×Y ( i+ 1, j )+1 ×Y ( i+ 1, j+ 1)−1 ×Y ( i+ 1, j− 1)   (9) [0115] The gradient G(i, j) in the pixel of interest (i, j) is calculated by equation (10) by using Δx(i, j) and ΔY(i, j). [0000] G ( i, j )=Δ X ( i, j )+Δ Y ( i, j )   (10) [0116] The maximum value G max of the gradient of the calculated gradient G of all pixels is determined. In the second embodiment, the binarization threshold value is calculated by the following equations (11) and (12) by using the most frequency luminance value of the partial image and the maximum value G max of the gradient of the partial image. [0000] Binarization threshold value=most frequent luminance value of partial image+maximum value G max of gradient×ε(0<ε<1)   (11) [0000] Binarization threshold value=most frequent luminance value of partial image+δ(δ>0)   (12) [0117] Equation (11) is applied if maximum value G max of gradient×ε>δ, and equation (12) is applied if maximum value G max of gradient×ε≦δ. In equations (11) and (12), ε and δ are variables that can be set by the user, and the user can change the values of ε and δ depending on the measuring target. The threshold value for extracting the particle can be calculated in accordance with the luminance of each particle by calculating the binarization threshold value by equation (11). [0118] In the second embodiment, the most frequent luminance value in the partial image is the luminance value of the background of the partial image by calculating the threshold value by equation (11), and thus the portion of the partial image having a luminance larger than the luminance value of the background by a predetermined luminance value (maximum value of luminance gradient in partial image×ε) corresponding to the luminance of the particle can be extracted as the particle image. [0119] FIG. 23 is a view showing the particle image extracted based on the threshold value set by the binarization threshold value setting processing according to example 1 (first embodiment of the present invention), and the visual particle image. FIG. 24 is a view showing the particle image extracted based on the threshold value set by the binarization threshold value setting processing according to example 2 (second embodiment of the present invention), and the visual particle image. FIG. 25 is a view showing the particle image extracted based on the threshold value set by the binarization threshold value setting processing according to a comparative example (one prior art example), and the visual particle image. The comparative experiment verifying the effects of the present invention will now be described with reference to FIGS. 13 and 23 to 25 . The images 1 to 4 in FIGS. 23 to 25 are the particle images extracted from the partial image of the same particle. In the comparative experiment, a case where the particle image is extracted from the partial image obtained through imaging by performing the dark-field illumination will be described. [0120] In the particle analyzer according to the comparative example, the binarization threshold value is calculated by equation (12) after obtaining the luminance histogram (see FIG. 13 ), different from the binarization threshold value setting processing of the first embodiment and the second embodiment. [0000] Binarization threshold value=most frequent luminance value+η(η≧δ)   (12) [0121] With respect to the threshold value calculated by equation (12), the same value is set for the binarization threshold value for the image imaged from one sample, as opposed to the first embodiment and the second embodiment. Other configurations are the same as the first embodiment. [0122] The imaging is performed on the sample of a standard particle (latex particle) having a substantially even particle diameter, and the variable η of equation (12) is set such that the particle image is extracted with the smallest error by the particle analyzer according to the comparative example. The average particle diameter of the sample is calculated based on the particle image extracted in the case of the set variable η. [0123] The particle image is extracted by the binarization threshold value setting processing according to the first embodiment with respect to the same partial image and the average particle diameter of the particle image is calculated, and the variable β of equation (6) is set such that the calculated average particle diameter becomes a value close to the average particle diameter of the comparative example. Similarly, for the binarization threshold value setting processing according to the second embodiment, the variable ε of equation (11) is set such that the average particle diameter becomes a value close to the average particle diameter of the comparative example. The sample including various particles having different luminance values is imaged by the particle analyzer with the variables η, β and ε set as above. The particle image is then extracted based on the respective threshold values set by the binarization threshold value setting processing according to the first embodiment (example 1), the second embodiment (example 2), and the prior art example (comparative example) with respect to the obtained partial image. The morphological features (circle equivalent diameter and degree of circularity) of the particle are calculated based on the extracted particle image. [0124] The particle image and the morphological features of example 1, example 2, and the comparative example are respectively shown in FIGS. 23 , 24 , and 25 . In FIGS. 23 to 25 , the brightness of the particle image is reduced in order of image 1 to image 4 . [0125] As shown in FIGS. 23 to 25 , in the image 4 in which the brightness of the particle is the smallest, difference in the extraction result of the particle is not found between example 1, example 2, and the comparative example. In the image 3 in which the particle is brighter than in the image 4 , an error occurs between the visual particle image (hatching portion) and the extraction result (thick solid line portion) in the comparative example. In other words, a range larger than the visual particle image is extracted as the particle image. In the image 3 , error is not found between the particle image (hatching portion) and the extraction result (thick solid line portion) in examples 1 and 2. In the images 1 and 2 of the particle much brighter than the image 3 , a range significantly larger than the visual particle image is extracted as the particle image in the comparative example, and thus the error is significantly shown. In examples 1 and 2, on the other hand, error is not found between the visual particle image and the extraction result. [0126] With regards to the morphological features, in the image 4 , a large difference is not found among example 1, example 2, and the comparative example. In the images 1 to 3 , it is apparent that the circle equivalent diameter of the comparative example is large compared to the circle equivalent diameter of example 1 and example 2. In other words, in the images 1 to 3 of the comparative example, a range larger than the visual particle image is extracted as the particle image, and thus the circle equivalent diameter is assumed to have increased. In the images 1 , 2 , and 4 of the particle having a shape relatively close to a circle, a large difference is not found in the degree of circularity among example 1, example 2, and the comparative example. In the image 2 in which an elongate particle is imaged, on the other hand, a large difference is found between the degree of circularity of examples 1 and 2 and the degree of circularity of the comparative example. In other words, in the comparative example, as a result of extracting a range larger than the visual particle image as the particle image, the extracted particle image has a rounded shape, and thus the degree of circularity is assumed to have increased. [0127] Therefore, in the comparative experiment, the particle image can be extracted without large error with the visual particle image for all images 1 to 4 having different brightness of particles in examples 1 and 2 where the binarization threshold value is set for every particle. A difference is found between the morphological feature of the comparative example in which a range larger than the visual particle image is extracted as the particle image and the morphological feature of examples 1 and 2. Therefore, the morphological features of examples 1 and 2 are assumed to indicate a value close to the actual morphological feature of the particle than the morphological feature of the comparative example. [0128] The embodiments and examples disclosed herein are merely illustrative in all aspects and should not be recognized as being restrictive. The scope of the invention is defined by the claims rather than the description of the embodiments and the examples, and the meaning equivalent to the claims and all modifications within the scope are encompassed therein. [0129] For instance, an example of setting the binarization threshold value for every particle when performing the dark-field illumination is shown in the first and the second embodiments and the examples, but the present invention is not limited thereto, an the binarization threshold value may be set for every particle even when performing the bright-field illumination. [0130] In the second embodiment and the examples, an example of calculating the gradient of the luminance of the partial image by using the Sobel filter is described, but the present invention is not limited thereto, and other filters such as Prewitt filter or Roberts filter may be used. [0131] In the present embodiment, an example of setting the binarization threshold value for every particle and binarizing the gray scale partial image including the partial image with the set threshold value to extract the particle is shown, but the present invention is not limited thereto. For instance, the partial image including the particle image may be a color image. When extracting the particle image from the color image, the particle image and the background may be distinguished based on the difference in tone. Specifically, when one of the components of RGB changes with exceeding a predetermined value between a certain pixel and an adjacent pixel, the boundary between the particle image and the background is recognized between such two pixels, and the particle image is extracted. In this case, the difference in tone with respect to the background is assumed to differ for every particle depending on the extent of illumination of the particle, and thus the amount of change in RGB upon recognizing as the boundary between the particle image and the background is set for every particle to thereby accurately extract the particle image depending on the luminance of the particle. [0132] In the present embodiment, cutout from the still image to the partial image is performed in the image processing substrate 6 , and the image processing result data including the cut out partial image is analyzed in the image data processing unit 2 b, but the present invention is not limited thereto. For instance, for instance, the video signal obtained from the CCD camera 82 may be transmitted to the image data processing unit 2 b, and generation of the still image, cutout of the partial image, and the analysis of the image processing result data including the cut out partial image may be performed in the image data processing unit 2 b. That is, the function of the image processing substrate 6 may be performed in the image data processing unit 2 b.

A particle analyzer capable of extracting particle image for each particle at high accuracy, if a plurality of images of a particle are imaged. Concretely, a particle analyzer comprising a controller, including a memory under control of a processor, the memory storing instructions enabling the processor to carry out operations, comprising: acquiring extraction parameters for each particle based on each image of a particles; extracting particle images from each image of a particles based on the extraction parameters obtained for each particle; and analyzing particles based on the extracted particle image.

BACKGROUND OF THE INVENTION The present invention generally relates to an improved apparatus and method for calibrating an image-capturing device that is connected to a document feeder. More particularly, it relates to an apparatus and method for calibrating a scanner which positions a calibration strip within the document feeder into an optical path of a scanner head assembly while the assembly is ready to scan a document fed by the document feeder. Image-capturing peripherals such as scanners have become increasingly useful, affordable and common devices for homes and businesses. These devices are useful for capturing and storing images such as text, graphic or pictorial images contained on documents. Various types of scanners include flatbed, drum and handheld scanners. With a flatbed scanner, one of the most common types of scanners, a document to be scanned is typically placed onto a transparent glass platen of the scanner, where a scanner head assembly (also referred to as a carriage assembly) moves underneath the document to capture the image contained on the document. The image in digital form is often transmitted to a connected computer, though it may instead be stored within the scanner, or transmitted directly to another peripheral such as a printer or facsimile (fax) machine. To scan a quantity of documents, a document feeder (such as an automatic document feeder or ADF) may be attached to the scanner to feed documents over the scanner head assembly, where the images on the documents are captured as they pass over the scanner head assembly. Often, a scanner and document feeder are integrated with a printer or fax machine to form a multi-function printer. Alternatively, the scanner may digitally send image information to the printer. FIG. 1 is a cross-sectional view of a typical flatbed scanner combined with a document feeder. A scanner, indicated generally at 10 , includes a head assembly 12 having a scanning lamp for producing a light for illuminating a document through a glass platen 14 , and may also contain mirrors and a lens to direct and focus the reflected light. The head assembly 12 includes a photodetector, such as a charge-coupled device (CCD) containing an array of pixels, each of which are configured to detect the reflected light and convert it into a signal for processing by another peripheral or by a connected computer (not shown). The head assembly 12 travels longitudinally along one or more rails 16 of the scanner 10 , and is driven by a pulley and one or more rollers (not shown). A document feeder 20 , which may be attached to the scanner 10 via hinges (not shown), feeds the paper into a scanning position along a generally U-shaped paper path 22 (more clearly shown in FIGS. 2 and 3 ), substantially surrounding a guiding mechanism such as a typically hollow cylindrical guide 50 . The document feeder 20 uses a feeding mechanism having a series of rollers, including a pick-up roller 24 , pairs of feed rollers 26 , 28 , 30 , and a pair of delivery rollers 34 to feed the paper through the paper path 22 . A transparent guide strip 36 of polyester, such as MYLAR, guides the paper along a bottom portion of the paper path 22 . A section 38 of the guide strip 36 allows the head assembly 12 , when in a scan position 40 (as shown in FIGS. 1 and 2 ) to capture images on paper, because the paper is within an optical path (field of view) of the head assembly. Before scanning one or more documents, a scanner is typically calibrated for photo response non-uniformity (PRNU) calibration, among other things. FIG. 3 shows a simplified representation of a typical scanner/document feeder with the head assembly 12 in a predetermined “home” (calibration) position 42 . To calibrate the scanner 10 , a stationary calibration strip 44 is attached to the scanner over the home position 42 of the head assembly 12 . The strip is positioned away from the paper path 22 and is thereby protected from dust from the paper being scanned. The head assembly 12 scans the stationary, preferably white calibration strip 40 to calibrate the scanner 10 in a manner known in the art. When scanning a document fed by the document feeder 20 , and referring to FIG. 2 , the head assembly 12 has to move from the home position 42 to the scan position 40 so that a portion of the paper being scanned is in the optical path or field of view of the head assembly 12 through the portion 38 of the guide strip 36 . The distance between the home position 42 and the scan position 40 is typically about 13 mm, but of course this distance may vary. To produce a high quality scan, calibration ideally should be done for every scan page. However, for high speed document feeding, it is almost impossible to calibrate every scan page because of the mass and inertia of the head assembly 12 . Because additional time and power are required to activate the head assembly 12 for every ADF-fed scan job, the scan performance is gradually degraded, due to wear on the head assembly 12 , and its mechanism for movement. The redundant quick and short jacking motion of the head assembly 12 can detrimentally impact the scan quality of the scanner 10 . Because about 80% of overall scan jobs are fed from the document feeder for a typical MFP, a significant improvement in reliability and scan quality of the scanner, as well as the print quality of connected printers, would result if the head assembly remained stationary during ADF-fed scanning jobs. BRIEF SUMMARY OF THE INVENTION The present invention provides an inventive apparatus for calibrating an image-capturing apparatus, such as a scanner, of the type which has a document feeder. The apparatus includes a calibration member that is disposed within the document feeder and is movable to a position within the optical path of the scanner head assembly when it is ready for scanning. Before a scan job, or before an individual document is scanned by the scanner head assembly, the head assembly scans the calibration member for the purpose of calibrating the scanner. In this way, it is possible to calibrate the scanner head assembly without moving the scanner from its scan position. In one embodiment, a wheel assembly is provided for rotating the calibration member into and out of the optical path of the scanner head assembly. A cam, together with a biasing member, moves the wheel assembly between two positions, so that the calibration member is either exposed to the scanner head assembly or not. In a preferred embodiment, the calibration apparatus includes a wheel assembly contained within a cylindrical guide of the document feeder, having a calibration strip attached to an outer circumferential surface. The cylindrical wheel rotates about an axis parallel to the length of the head assembly, across the width of the document feeder. A cam is provided for driving rotation of the wheel assembly by contacting a first flat surface of the wheel assembly. A biasing member is attached to a second flat surface of the wheel assembly, to bias the wheel assembly against the cam. The wheel assembly is rotated into either of two positions to position the calibration strip either into an exposed position (into the optical path of the head assembly) or non-exposed position (out of the optical path) while the head assembly is in a position ready for scanning. In a further preferred embodiment, a cleaning blade is also provided to remove contaminants from the calibration strip. DESCRIPTION OF THE DRAWINGS FIG. 1 is a side sectional view of a typical prior art scanner combined with a document feeder; FIG. 2 is a side illustration of a typical prior art scanner and document feeder with a scanner head assembly in a scan position; FIG. 3 is a side illustration of the scanner and document feeder of FIG. 2 , with the scanner head assembly in a home position; FIG. 4 is a simplified side illustration, partially in cross-section, of a scanner combined with a document feeder fitted with one embodiment of the calibration apparatus of the present invention, with the head assembly in a scan position, and the wheel assembly rotated so that the calibration strip is in the optical path of the head assembly; FIG. 5 is a perspective view of a wheel assembly used in one embodiment of the calibration apparatus and method of the present invention; and, FIG. 6 is a side illustration of the scanner and document feeder of FIG. 4 , with the head assembly in a scan position, with the wheel assembly rotated so that the calibration strip is retracted out of the optical path of the head assembly. DETAILED DESCRIPTION While the apparatus is described and pictured herein for a flatbed scanner having a document feeder, it is important to understand that the principles of the inventive calibration apparatus can be applied for any image-capturing apparatus that is combined or equipped with a document feeder. The descriptions that follow are in no way intended to limit the scope of the inventive calibration apparatus to an MFP or similar device. Where appropriate, the same reference characters are used to designate like parts. Turning now to FIGS. 4-6 , a calibration apparatus 46 having a wheel assembly 52 is shown contained within the cylindrical guide 50 . A calibration strip 48 is attached to a lower portion of an outer circumference 53 of the wheel assembly 52 , and runs along the length of the wheel assembly, parallel to the length of the head assembly 12 . The wheel assembly 52 , preferably made of lightweight material such as plastic, contains an inner cylindrical portion 54 , which rotates about an axle 56 . The outer circumference 53 of the wheel assembly 52 is concentric with the inner cylindrical portion 54 , extending approximately 240° around the cylindrical guide 50 , as shown in section in FIGS. 4 and 6 . Preferably, the wheel assembly 52 contains a series of structural members 58 extending around the wheel assembly, located at approximately 60° intervals. First and second exposed flat surfaces 60 , 62 are thus formed, which extend longitudinally along the wheel assembly 52 , as shown in FIG. 5 . The calibration strip 48 is preferably made of lightweight material such as MYLAR, and may be attached to the wheel assembly 52 via adhesive, although other methods of attachment are possible. A space or recess 49 in the outer circumference 53 of the wheel assembly may be provided for accommodating the calibration strip 48 . The calibration strip 48 is typically a white strip employed for photo response non-uniformity (PRNU) calibration. The calibration strip 48 preferably has a length sufficient to be viewed by all of the pixel devices in the head assembly 12 while the head assembly is in its scan position 40 . A cam 64 is disposed within the cylindrical guide 50 , abutting the first flat surface 60 of the wheel assembly 52 . Substantially semicircular in section, the cam 64 extends along a longitudinal portion of the wheel assembly 52 , as shown in FIG. 5 . The cam 64 is stationed on a pivot 66 , which is coupled to a pick-up mechanism (not shown) for the document feeder 20 , or other such mechanism for actuating rotation of the pivot. The cam 64 abuttingly contacts the first flat surface 60 of the wheel assembly either with a flat surface 68 of the cam or (tangentially) with its curved surface 70 . When the cam 64 rotates so that its point of contact with the wheel assembly 52 is changed from the cam's flat surface 68 to its curved surface 70 , the cam rotationally urges the wheel assembly in the counterclockwise direction, to the position shown in FIG. 4 . The wheel assembly 52 thus positions the calibration strip 48 in the optical path of the head assembly 12 , over the portion 38 of the guide strip 36 . Thus, while the head assembly 12 is ready to scan in position 40 , it can also scan the calibration strip 48 to calibrate the scanner 10 . A biasing member 72 , such as a spring, is connected at one end to the second flat surface 62 of the wheel assembly 52 and at its other end to a fixed stop 74 within the document feeder 20 . The fixed stop 74 runs parallel to the axle 56 of the wheel assembly 52 . The biasing member 72 constantly exerts a compressive, clockwise biasing force on the wheel assembly 52 , rotationally urging the wheel assembly toward the cam 64 . Therefore, when the cam pivot 66 rotates so that the flat surface 68 of the cam 64 contacts the wheel assembly 52 , the wheel assembly rotates clockwise against the cam. The wheel assembly 52 is rotated to the position shown in FIG. 6 , and thus retracts the calibration strip 48 out of the optical path of the head assembly 12 . The wheel assembly 52 is constantly subjected to opposing rotational forces from the cam 64 and the biasing member 72 . The balance of these forces holds the wheel assembly 52 in the positions shown in FIGS. 4 and 6 , respectively. When the calibration strip 48 is exposed to the optical path of the head assembly 12 , it is simultaneously exposed to paper dust. To help prevent dust from the paper from contaminating the calibration strip 48 , a preferably stationary cleaning blade 76 is provided. The cleaning blade 76 is situated within and runs along the length of the cylindrical guide 50 , parallel to the length of the calibration strip 48 . The cleaning blade 76 is preferably manufactured of rubber and attached to the inner surface of the cylindrical guide 50 by known means. When the wheel assembly 52 rotates clockwise, and the calibration strip 48 is thus moved away from the optical path of the head assembly 12 , the cleaning blade 76 wipes the calibration strip 48 , cleaning the calibration strip. With regard to the scanner calibration operation, at the beginning of a scan job, or as an individual page is scanned, the cam pivot 66 is configured to rotate. This in turn rotates the cam 64 so that its curved surface 70 tangentially contacts the first flat surface 60 of the wheel assembly 52 . The wheel assembly rotates counterclockwise so that the calibration strip 48 is exposed to the optical path of the head assembly 12 of the scanner 10 . The biasing member 72 biases the wheel assembly 52 clockwise against the cam 64 to hold the wheel assembly in this position. The head assembly 12 then scans the calibration strip 48 to calibrate the scanner 10 . After the scanner 10 has been calibrated, the cam pivot 66 again rotates, rotating the cam 64 until the flat surface 68 of the cam contacts the flat surface 60 of the wheel assembly 52 . The biasing member 72 rotates the wheel assembly 52 clockwise, moving the calibration strip 48 out of the optical path of the head assembly 12 , and against the cleaning blade 76 so that the calibration strip 48 is wiped clean for the next calibration. This calibration operation, or a similar one, can be configured to occur at the beginning of an ADF-fed scan job, or before individual pages are fed by the ADF. Such configuration will be apparent to those skilled in the art. By employing a lightweight, low inertial calibration strip on the document feeder, additional motion of the head assembly is eliminated for ADF-fed scan jobs. A minimum of additional parts is necessary because the cam can be configured to be coupled to the existing pickup mechanism. As an additional benefit, since the calibration strip is in the document feeder behind the MYLAR guide strip (as shown in FIG. 4 ), the calibration strip has an identical optical path as that of a portion of an image scanned by an ADF-fed scan. Thus, imperfections, scratches, and smears present in the transparent portion of the guide strip are calibrated out, which is not possible for conventional scanner head assembly movement calibration. From the foregoing description, it should be understood that an improved apparatus and method for calibrating an image-capturing device with a document feeder has been shown and described, which has many desirable attributes and advantages. With this inventive calibration apparatus, approximately 80% of scan jobs do not require movement of the scanner head assembly. As a result, the acoustic level of the scanner is reduced, and the reliability of the scanner mechanism is improved. The scan quality is improved due to identical optical path calibration. Impairment of print quality due to vibration of the scanner is reduced, and cost savings are derived due to an increased life cycle of the scanner. While various embodiments of the present invention have been shown and described, it should be understood that other modifications, substitutions and alternatives can be made without departing from the spirit and scope of the invention, which should be determined from the appended claims.

An apparatus and method for calibrating a scanner connected to a document feeder are provided. In one embodiment, the apparatus includes a calibration strip attached to a rotatable wheel assembly disposed within the document feeder. A cam is provided to rotate the wheel assembly and expose the calibration strip to the field of view of a head assembly of the scanner for calibration. The cam is configured to then rotate the wheel assembly in the opposite direction, so that the calibration strip is no longer exposed to the head assembly. A cleaning blade may be provided to wipe the calibration strip as it is moved to its non-exposed position.

REFERENCE TO RELATED APPLICATIONS [0001] The present application is a continuation application of U.S. patent application Ser. No. 14/640648, filed Mar. 6, 2015, which claims priority to Provisional U.S. Application No. 61/948964, filed Mar. 6, 2014, both entitled “METHODS AND DEVICES FOR DISPLAYING TREND AND VARIABILITY IN A PHYSIOLOGICAL DATASET,” and both are incorporated herein in their entirety. BACKGROUND [0002] 1. Field of the Invention [0003] The invention is directed to devices and methods for displaying a physiological dataset in graphical form. Specifically, the invention is directed toward devices and methods for displaying trend and variability of a physiological dataset in graphical form. [0004] 2. Background of the Invention [0005] Medical professionals use charts of physiological data on a regular basis to come to decisions critical to patient care. Patient information charts have historically been written or printed on paper, however with the advent of electronic displays, charts of patient's data are increasingly found in electronic forms. Everything from patient health information to real-time physiological data is transitioning from paper to electronic form. The transition to electronic form, linked to computers or other programmable equipment, enables new and improved visualizations to be applied to patient data, especially physiological data. [0006] Physiological data is typically acquired from the patient by means of a variety of sensors. Data can be acquired over the course of a patient's life at regularly scheduled exams, or over a series of hours, minutes, or in real-time in the case of continuous monitoring. [0007] Patients in a hospital may be connected to a variety of sensors, monitors and devices which produce real-time traces of physiological signals, real-time and near-real-time calculations of physiological parameters. For example, an ICU patient could be simultaneously connected to devices which record ECG, EMG, EEG, capnography, pulse oximetry, pneumography, blood pressure, etc., yielding a plethora of physiological parameters including heart rate, end-tidal CO2 or end-expiratory CO2, O2 saturation, respiratory rate, tidal volume, and minute ventilation. The sheer number of physiological datasets measured from a patient in the hospital can easily lead to information overload. [0008] The information overload can cause healthcare providers to overlook aspects of the data that could indicate important aspects of the patient's condition or the patient's state. Therefore, there is a need to reduce information overload. SUMMARY OF THE INVENTION [0009] The present invention overcomes the problems and disadvantages associated with current strategies and designs and provides new tools and methods of displaying a physiological dataset in graphical form. [0010] One embodiment of the invention is directed to a method of displaying trends and variability in a physiological dataset. The method comprises the steps of obtaining the physiological dataset, applying a smoothing algorithm to the physiological dataset to obtain a trend of the physiological dataset, applying a variability algorithm to the physiological dataset to obtain the variability of the physiological dataset, outputting a graph of the trend of the physiological dataset, and outputting a graph of the variability of the physiological dataset. [0011] In a preferred embodiment, the physiological dataset is based on data obtained from a patient's respiratory system. Preferably, the smoothing algorithm is one of a moving average algorithm and a digital filter algorithm. The graph of the trend of the physiological dataset and the graph of the variability of the physiological dataset are preferably one of overlaid and graphed adjacently. Preferably, the graph of the variability of the physiological dataset comprises an envelope bounded on the top by a plot of the maximums identified by the variability algorithm and bounded on the bottom by a plot of the minimums identified by the variability algorithm. The space between the bounds is preferably shaded and the graph of the variability of the physiological dataset is preferably used to assess and diagnose apnea. [0012] In a preferred embodiment, the physiological dataset is interbreath interval data. Preferably, the graph of variability of the physiological dataset is a function of fractal scaling coefficients calculated at various time points and over various time windows of the dataset. Preferably, the graph of variability of the physiological dataset comprises one or more of, error bars, line graphs, momentum bars, shaded areas under a curve, and a stochastic plot. In a preferred embodiment, the magnitude of the variability which is displayed by the graph of variability of the physiological dataset is calculated as a function of at least one of, the raw dataset, the smoothed dataset, multiple smoothed datasets, the fractal scaling coefficients of the dataset, or the stochastic coefficients of the dataset. [0013] Another embodiment of the invention is directed toward a device comprising a transthoracic impedance measurement device to obtain a physiological dataset, a processor receiving the physiological dataset from the measurement device, and an output device coupled to the processor. The processor is adapted to: apply a smoothing algorithm to the physiological dataset to obtain a trend of the physiological dataset, apply a variability algorithm to the physiological dataset to obtain the variability of the physiological dataset. The output device is adapted to: output a graph of the trend of the physiological dataset and output a graph of the variability of the physiological dataset. [0014] Another embodiment of the invention is directed toward a system for displaying trends and variability in a physiological dataset. The system comprises a patient monitoring device, at least one sensor coupled to the patient monitoring device, a processor contained within the patient monitoring device and receiving patient data from the at least on sensor, a screen contained within the patient monitoring device and receiving display information from the processor. The processor: obtains the physiological dataset from the at least one sensor, applies a smoothing algorithm to the physiological dataset to obtain a trend of the physiological dataset, applies a variability algorithm to the physiological dataset to obtain the variability of the physiological dataset, outputs a graph of the trend of the physiological dataset to the screen, and outputs a graph of the variability of the physiological dataset to the screen. [0015] In a preferred embodiment, the physiological dataset is based on data obtained from a patient's respiratory system. Preferably, the smoothing algorithm is one of a moving average algorithm and a digital filter algorithm. The graph of the trend of the physiological dataset and the graph of the variability of the physiological dataset are preferably one of overlaid and graphed adjacently. Preferably, the graph of the variability of the physiological dataset comprises an envelope bounded on the top by a plot of the maximums identified by the variability algorithm and bounded on the bottom by a plot of the minimums identified by the variability algorithm. The space between the bounds is preferably shaded and the graph of the variability of the physiological dataset is preferably used to assess and diagnose apnea. [0016] In a preferred embodiment, the physiological dataset is interbreath interval data. Preferably, the graph of variability of the physiological dataset is a function of fractal scaling coefficients calculated at various time points and over various time windows of the dataset. Preferably, the graph of variability of the physiological dataset comprises one or more of, error bars, line graphs, momentum bars, shaded areas under a curve, and a stochastic plot. In a preferred embodiment, the magnitude of the variability which is displayed by the graph of variability of the physiological dataset is calculated as a function of at least one of, the raw dataset, the smoothed dataset, multiple smoothed datasets, the fractal scaling coefficients of the dataset, or the stochastic coefficients of the dataset. [0017] Other embodiments and advantages of the invention are set forth in part in the description, which follows, and in part, may be obvious from this description, or may be learned from the practice of the invention. DESCRIPTION OF THE DRAWING [0018] The invention is described in greater detail by way of example only and with reference to the attached drawing, in which: [0019] FIG. 1 : Example MV trend. (A) Raw data. Note the highly varying signal making it difficult to determine the overall respiratory status. (B) Visualizing a trend in the data. The average trend helps identify general drifts in the measurements. (C) Visualizing the variability in the data. The variability envelope when applied in conjunction with the trend in the data contains all relevant information from the raw signal, yet presents it in an easier-to-comprehend fashion. [0020] FIG. 2 : Examples of average trends and variance envelopes applied to a variety of respiratory signals (MV, TV, RR) [0021] FIG. 3 : Example of adequate ventilation (MV) over time, as visualized by a stable trend and a stable envelope. [0022] FIG. 4 : Example of an agitated patient who may be undermedicated. Note that the trend in the data increases slightly, whereas the envelope increases substantially with time, indicative of increased respiratory variability, likely caused by increase in pain and discomfort. [0023] FIG. 5 : Example of a patient who is headed towards respiratory compromise. The average MV trend is systematically decreasing and so is the variability in the MV data. [0024] FIG. 6 : Example of a patient with apneic breathing pattern. Note the increase in variability (with envelope encroaching on the MV=0 line) coupled with a decrease in the overall trend. This is indicative of a repetitive breathing pattern with significant respiratory pauses and interspersed large “rescue” breaths. [0025] FIG. 7 : Example of a patient with apneic breathing pattern as a result of opioid administration. Note the increase in variability (with envelope encroaching on the MV=0 line) coupled with a decrease in the overall trend. This is indicative of a repetitive breathing pattern with significant respiratory pauses and interspersed “rescue” breaths. [0026] FIG. 8 : Example of a patient who is headed towards respiratory compromise following opioid administration. The average MV trend is systematically decreasing and so is the variability in the MV data. [0027] FIG. 9 : Example of a patient who may be undermedicated. Note that, despite receiving a dose of opioids, the trend in the data remains practically unchanged, whereas the envelope increases with time, indicative if increased respiratory variability, likely caused by increase in pain and discomfort. [0028] FIG. 10 : Example of a patient displaying hypopneic breathing following opioid administration. The decrease in both the trend and variability in the data suggest a regular breathing pattern at lower volumes and rates. [0029] FIG. 11 : Example of adequate ventilation (MV) over time, as visualized by a small change in the trend (expected result of opioid administration) and a stable envelope. [0030] FIG. 12 : Example of an embodiment of the structure of the device disclosed herein. [0031] FIG. 13 : Example of an embodiment of a patient monitoring device. DESCRIPTION OF THE INVENTION [0032] As embodied and broadly described herein, the disclosures herein provide detailed embodiments of the invention. However, the disclosed embodiments are merely exemplary of the invention that may be embodied in various and alternative forms. Therefore, there is no intent that specific structural and functional details should be limiting, but rather the intention is that they provide a basis for the claims and as a representative basis for teaching one skilled in the art to variously employ the present invention [0033] It has surprisingly been discovered that a visualization of physiological data aids healthcare providers in quickly assessing important features of a monitored physiological parameter by reducing the perceived complexity of a recorded dataset. The invention achieves this by simultaneously displaying a physiological parameter's trend and variability as well as their evolution over time. This is in contrast to existing methods for displaying physiological datasets, which generally include applying various filtering (smoothing) algorithms. Filters generally reduce the perceived complexity of a dataset, enabling a better assessment of trends in the data, but in the process they reduce variability, impairing the ability to assessment changes in variability in the data. Variability has proven to be an important feature of physiological signals. For example, reduced heart rate variability can predict mortality following a heart attack. [0034] A caregiver would not be able to assess heart rate variability from a chart of heart rate where the dataset is filtered. A solution to this problem is to overlay the filtered signal with an indication of variability. [0035] The method described herein is a means of displaying a physiological dataset within a graphical user interface. The dataset is calculated and/or monitored with respect to an independent variable, e.g. time. The dataset is a measurement, calculation or derivation related to a tissue, organ, organ system or physiological system. Features of the time-series analysis including the value, trend of the value and variability of the dataset correlate with specific disease stated related to the monitored tissue, organ or organs system. The features of the time series analysis may also correlate with overall patient health. The method of displaying the dataset enables medical caregivers to quickly assess important time-series features of the dataset. [0036] The method specifically aids in identifying the trend and variability of the dataset with respect to an independent variable, e.g. time. The assessment of variability combined with the trend aids in assessing patient health or diagnosing or predicting disease states. [0037] The dataset may be acquired from the patient by a means of an analog or digital sensor. The dataset may represent a physiological signal or a calculated, estimated or derived physiological parameter or health index. A health index is a numerical representation based on one or more physiological parameters, or features of their signals. The health index correlates with patient health, disease state or overall patient status. In one embodiment of the invention the dataset is a respiratory parameter derived from a transthoracic impedance measurement. In one embodiment the dataset is a calculation of minute ventilation, calculated based on a measurement of transthoracic impedance. In one embodiment the dataset is a respiratory health index based on the combination of variability in tidal volume, the trend in minute ventilation and the duty cycle of the respiratory rate. In another embodiment of the invention, the dataset is the rapid shallow breathing index derived from the patient's respiratory parameters over time. [0038] In one embodiment of the invention, the physiological parameter is Minute Ventilation (MV). The trends in MV combined with an assessment of the variability of MV can assist medical caregivers to identify periods of apnea, hypopnea, hyperventilation, impending respiratory failure/arrest, response to narcotics, pain level, and/or depth of anesthesia. [0039] The method described herein is preferably applied to the dataset first by implementing a filter to reduce the perceived complexity of the dataset. The filter enables the caregiver to quickly assess trends in the data without suffering from information overload of the entire dataset. The filter applied to the dataset may be applied in software or electrical hardware. The filter applied to the dataset may be a time-domain filter or frequency domain filter. The filter may be moving average, a weighted moving average, a smoothing algorithm, a Chebyshev filter, a Butterworth filter, a Bessel filter, an elliptic filter, constant k filter, m-derived filter, special filter, top-hat filter, or other Fourier-transform-based filter. The window of the filter may be 2 minutes, 5 minutes, 10 minutes, 1 hour, a custom time frame, or another time frame and preferably corresponds to the rate at which trends are likely to appear in the data. [0040] An embodiment of the invention implements a smoothing average over a two-minute window. This smoothed data is then displayed as the trend over time. The middle panel in FIG. 1 shows an example of the smoothed trend line overlaid on the dataset. [0041] After the filter highlights the trend in the data, the method preferably adds a visual indication of variability to the graph. The visual indication of variability preferably consists of an envelope which overlays the smoothed trend. The visualization preferably updates in real-time for monitored parameters, but may be applied retroactively on historical data. [0042] In one embodiment of the invention, the minimum and maximum points within each window are determined and stored in an array of peaks. Preferably once the minimum and maximum points are determined in each window position, all the peaks are plotted on the graph. The maximum peaks are preferably then connected by line segments, with points between the peaks being interpolated. The minimum points are also preferably connected by line segments with points between the minimum peaks being interpolated. The bottom panel in FIG. 1 is an example of this envelope. In this embodiment, the area within the maximum envelope and the minimum envelope may be shaded. [0043] A quantitative coefficient of variability is preferably calculated for each point on the chart and displayed. The coefficient of variability is preferably calculated from a window of data points which is smaller than the total number of points on the graph. The coefficient of variability is preferably based on the statistics of the dataset calculated within the window. The coefficient of variability is preferably a function of statistical variance, standard deviation, or entropy. [0044] In one embodiment, error bars are applied behind the smoothed dataset. The error bars are preferably a function of the standard deviation of the dataset within a window of, for example, 2 minutes. The error bar is preferably overlaid on the graph at the last point in the window, the center point in the window, or the first point in the window. [0045] In one embodiment, a function of one or more fractal scaling coefficients, or a function of a ratio of at least two fractal scaling coefficients is utilized and overlaid on the graph. In one embodiment, a set of fractal scaling coefficients is calculated for the entire dataset (FC 1 ), then again for the window (FC 2 ). The coefficient of variability is preferably calculated as a function of one or more coefficients from the set of FC 1 as compared to FC 2 . One embodiment of the visualization is to display variability as a function of the difference or absolute value of the difference of two or more smoothing algorithms applied to the dataset. In one embodiment of the invention, two moving average algorithms are applied to the dataset, one with a window of ten (10) minutes and one with a window of two (2) minutes. The visualization preferably consists of a graph of the two moving averages overlaid on each other, or both overlaid on the dataset, smoothed or un-smoothed. This may enable the caregiver to see the trend from the smoothed data as well as discern the absolute difference between the smoothed data trends. It is understood that when the two averages cross, i.e. the absolute difference between the two averages reaches zero, the trend in the data has changed direction. This can predict a rapid change in state and trigger an alarm signal. [0046] In another embodiment, the difference between the results of the two smoothing algorithms is calculated and displayed on a graph. The graph is preferably overlaid on the graph of the smoothed dataset, or appears in its own space. This visualization preferably provides an indicator of the momentum behind a trend, where a large difference between the results indicates a strong trend, and a small difference between the results indicates a stable trend. However, a change in sign indicates a reversal of the previous trend. [0047] Another visualization that can be applied to the data is a stochastic plot. The stochastic plot may be overlaid on the raw dataset or a smoothed dataset. The stochastic plot can be interpreted by a care provider to predict a patient's future status. [0048] In one embodiment of the invention, the visualization including a smoothing component and an indication of variability is applied to one or more datasets relating to the respiratory system. The user can interpret the visualization in order to assess or predict patient state, health state, respiratory status, disease state or response to a medical intervention. The user may also use the visualization of variability to diagnose a disease. The user may draw conclusions from the visualization including, an assessment of the patient's response to an opioid, a diagnosis or prediction of respiratory arrest, respiratory failure, apnea or cardiac arrest. The user may assess the patient's respiratory sufficiency, likelihood of successful extubation or the necessity of intubation. [0049] FIG. 3 illustrates an example of the display of the visualization algorithm on a minute ventilation dataset. The patient in the example maintains a similar minute ventilation and minute ventilation variability over time. A caregiver could draw the conclusion that the patient has a good status, free of various disease states. FIG. 11 shows an example of a healthy response to an opioid dose, with only a slightly downward trend on the MV dataset, and little change in the signal variability. This type of response would lead a caregiver to conclude that the patient is correctly dosed. [0050] FIG. 4 indicates an example of an agitated patient. In this instance, the increase in MV variability and MV trend as shown in the visualization could lead a caregiver to conclude that the patient is undermedicated and could adjust the patient's dose of pain medication accordingly. FIG. 9 is an example of a patient who responds idiosyncratically to an opioid dose. The variability increases, which could indicate restlessness and discomfort and general inefficacy of the pain medication. [0051] It is often critical for caregivers to respond to indications of respiratory compromise as quickly as possible. The example in FIG. 5 is a case in which a caregiver could use the visualization to diagnose respiratory compromise and undertake a medical intervention to prevent patient state from worsening. Interventions could include waking the patient, administering an opoid antagonist such as Naloxone, or intubating and ventilating the patient. FIG. 8 is an example of the visualization applied to an MV dataset in a patient suffering respiratory compromise as a result of a dose of an opioid. [0052] Apnea is a state in which the breathing is interrupted. It may result from a variety of causes, including opioid toxicity. The sooner opiate toxicity can be identified, the sooner a caregiver can undertake measures to prevent the patient's condition from worsening. Periods of apnea are generally followed by a period of rescue breathing which may include larger than normal or faster than normal breaths, which normalize over time. The difference between the breaths during these periods translates to a high index of variability in datasets related to the respiratory system. Apnea can be identified by a downward trend in minute volume, a high variability in respiratory rate, or interbreath interval, and a high variability in tidal volume and minute ventilation. FIG. 6 shows an example of the increased variability and decrease in trend in minute ventilation to indicate the onset of apnea. FIG. 7 shows an example of the onset of apnea as a symptom of opioid toxicity in response to a dose of opioid pain medication. [0053] FIG. 10 shows an example of the visualization on the MV dataset in a patient suffering hypopnea, or shallow breathing. In terms of the trend, it is difficult to differentiate hypopnea from apnea, however, the variability in each case is very different. The variability in the hypopneic patient's dataset is much lower, which allows a caregiver to differentiate between the two cases. [0054] The methods disclosed herein may also be applied to parameters associated with the circulatory system including measurements of the heart rate, or its inverse, beat-to-beat interval. Low variability in the heart rate can predict or, indicate, or quantify the progression of many conditions including myocardial infarction, congestive heart failure, diabetic neuropathy, depression or susceptibility to SIDS. In this embodiment, the envelope provides a visualization of heart rate variability to assist the caregiver in identifying, or assessing the risk of the aforementioned conditions. [0055] FIG. 13 depicts a preferred embodiment of a patient monitoring system 1300 adapted to calculated and display a physiological parameter's trend and variability as well as their evolution over time. Preferably, patient monitoring system 1300 is a portable device that can be mounted on an IV pole, attached to a bed, attached to a wall, placed on a surface or otherwise positioned. Patient monitoring system 1300 may be adapted for use during medical procedures, recovery, and/or for patient monitoring. Preferably, patient monitoring system 1300 is battery powered and/or has a power cable. Patient monitoring system 1300 preferably has at least one input port 1305 . Preferably, each input port 1305 is adapted to receive signals from one or more sensors remote to patient monitoring system 1300 . Additionally, patient monitoring system 1300 may further include wireless communication technology to receive signals from remote and wireless sensors. The sensors may be adapted to monitor for a specific patient characteristic or multiple characteristics. Patient monitoring system 1300 preferably is adapted to evaluate the data received from the sensors and apply the algorithms described herein to the data. Furthermore, the patient monitoring system 1300 may be able to receive custom algorithms and evaluate the data using the custom algorithm. [0056] Patient monitoring system 1300 preferably further includes a screen or display device 1310 . Preferably, screen 1310 is capable of displaying information about patient monitoring system 1300 and the patient being monitored. Screen 1310 preferably displays at least one graph or window of the patient's condition, as described herein. Each graph may be a fixed size or adjustable. For example, the graph may be customizable based on the number of data points, a desired length and/or time of measurement, or a certain number of features (i.e. breaths, breath pauses, or obstructed breaths). Additionally, the scale of the graph may be adjustable. Furthermore, the patient or caregiver (or clinician) may be able to choose what is displayed on screen 1310 . For example, screen 1310 may be able to display the mean, median, and/or standard deviation of data being monitored; the max, min and or range of data being monitored; an adaptive algorithm based on trend history; a adapted algorithm based on large populations of like patients (i.e. condition, age, weight, and events); and/or patent breathing parameters (i.e. blood pressure, respiratory rate, CO 2 , and/or O 2 rates). [0057] Patient monitoring system 1300 is preferably equipped with an alarm. The alarm can be an audio alarm and/or a visual alarm. The alarm may trigger based on certain conditions being met. For example, based on trends, real-time conditions, or patient parameter variability. The alarm may be customizable, both in sound/visualization and in purpose. The patient and/or caregiver may be able to navigate through multiple windows that display different information. For example, certain windows may display the graphs described herein, certain windows may display the patient's biographical data, and certain windows may display the system's status. Additionally, custom windows may be added (e.g by the patient, caregiver, or by the system automatically). For example, a custom window may be for clinical use, to mark events, or to display the patient's condition. [0058] In a preferred embodiment, patient monitoring system 1300 has a plurality of configurations. The configurations are preferably adapted to display relevant information to a caregiver or patient about the patient based on the patient's current condition. For example, for a patient undergoing a surgery, the nurse or doctor may need different information than for a patient recovering from an illness. Preferably, at the initiation of monitoring the patient, the patient monitoring system 1300 allows the patient or caregiver to select a configuration. Selectable configurations may include, but are not limited to specific procedures, specific illnesses, specific afflictions, specific patient statuses, specific patient conditions, general procedures, general illnesses, general afflictions, general patient statuses, and/or general patient conditions. Upon selection, preferably, the patient monitoring system 1300 will automatically display data relevant to the selection. In another embodiment, the patient monitoring system 1300 may automatically determine an appropriate configuration based on the data received from the patient. The patient or caregiver may be able to customize configurations once they are chosen. [0059] With reference to FIG. 12 , an exemplary system includes at least computing device 1200 , for example contained within the system depicted in FIG. 13 , including a processing unit (CPU) 1220 and a system bus 1210 that couples various system components including the system memory such as read only memory (ROM) 1240 and random access memory (RAM) 1250 to the processing unit 1220 . Other system memory 1230 may be available for use as well. It can be appreciated that the invention may operate on a computing device with more than one CPU 1220 or on a group or cluster of computing devices networked together to provide greater processing capability. The system bus 1210 may be any of several types of bus structures including a memory bus or memory controller, a peripheral bus, and a local bus using any of a variety of bus architectures. A basic input/output (BIOS) stored in ROM 1240 or the like, may provide the basic routine that helps to transfer information between elements within the computing device 1200 , such as during start-up. The computing device 1200 further includes storage devices such as a hard disk drive 1260 , a magnetic disk drive, an optical disk drive, tape drive or the like. The storage device 1260 is connected to the system bus 1210 by a drive interface. The drives and the associated computer readable media provide nonvolatile storage of computer readable instructions, data structures, program modules and other data for the computing device 1200 . The basic components are known to those of skill in the art and appropriate variations are contemplated depending on the type of device, such as whether the device is a small, handheld computing device, a desktop computer, a computer server, a handheld scanning device, or a wireless devices, including wireless Personal Digital Assistants (“PDAs”), tablet devices, wireless web-enabled or “smart” phones (e.g., Research in Motion's Blackberry™, an Android™ device, Apple's iPhone™), other wireless phones, a game console (e.g, a Playstation™, an Xbox™, or a Wii™), a Smart TV, a wearable internet connected device, etc. Preferably, the system is technology agnostic. [0060] Although the exemplary environment described herein employs the hard disk, it should be appreciated by those skilled in the art that other types of computer readable media which can store data that are accessible by a computer, such as magnetic cassettes, flash memory cards, digital versatile disks, cartridges, random access memories (RAMs), read only memory (ROM), a cable or wireless signal containing a bit stream and the like, may also be used in the exemplary operating environment. [0061] To enable user interaction with the computing device 1200 , an input device 1290 represents any number of input mechanisms, such as a microphone for speech, a touch-sensitive screen for gesture or graphical input, keyboard, mouse, motion input, speech, game console controller, TV remote and so forth. The output device 1270 can be one or more of a number of output mechanisms known to those of skill in the art, for example, printers, monitors, projectors, speakers, and plotters. In some embodiments, the output can be via a network interface, for example uploading to a website, emailing, attached to or placed within other electronic files, and sending an SMS or MMS message. In some instances, multimodal systems enable a user to provide multiple types of input to communicate with the computing device 1200 . The communications interface 1280 generally governs and manages the user input and system output. There is no restriction on the invention operating on any particular hardware arrangement and therefore the basic features here may easily be substituted for improved hardware or firmware arrangements as they are developed. [0062] For clarity of explanation, the illustrative system embodiment is presented as comprising individual functional blocks (including functional blocks labeled as a “processor”). The functions these blocks represent may be provided through the use of either shared or dedicated hardware, including, but not limited to, hardware capable of executing software. For example the functions of one or more processors presented in FIG. 12 may be provided by a single shared processor or multiple processors. (Use of the term “processor” should not be construed to refer exclusively to hardware capable of executing software.) Illustrative embodiments may comprise microprocessor and/or digital signal processor (DSP) hardware, read-only memory (ROM) for storing software performing the operations discussed below, and random access memory (RAM) for storing results. Very large scale integration (VLSI) hardware embodiments, as well as custom VLSI circuitry in combination with a general purpose DSP circuit, may also be provided. [0063] Embodiments within the scope of the present invention may also include computer-readable media for carrying or having computer-executable instructions or data structures stored thereon. Such computer-readable media can be any available media that can be accessed by a general purpose or special purpose computer. By way of example, and not limitation, such computer-readable media can comprise RAM, ROM, EEPROM, CD-ROM or other optical disk storage, magnetic disk storage or other magnetic storage devices, or any other medium which can be used to carry or store desired program code means in the form of computer-executable instructions or data structures. When information is transferred or provided over a network or another communications connection (either hardwired, wireless, or combination thereof) to a computer, the computer properly views the connection as a computer-readable medium. Thus, any such connection is properly termed a computer-readable medium. Combinations of the above should also be included within the scope of the computer-readable media. [0064] Computer-executable instructions include, for example, instructions and data which cause a general purpose computer, special purpose computer, or special purpose processing device to perform a certain function or group of functions. Computer-executable instructions also include program modules that are executed by computers in stand-alone or network environments. Generally, program modules include routines, programs, objects, components, and data structures, etc. that perform particular tasks or implement particular abstract data types. Computer-executable instructions, associated data structures, and program modules represent examples of the program code means for executing steps of the methods disclosed herein. The particular sequence of such executable instructions or associated data structures represents examples of corresponding acts for implementing the functions described in such steps. [0065] Those of skill in the art will appreciate the preferred embodiments of the invention may be practiced in network computing environments with many types of computer system configurations, including personal computers, hand-held devices, multi-processor systems, microprocessor-based or programmable consumer electronics, network PCs, minicomputers, mainframe computers, and the like. Networks may include the Internet, one or more Local Area Networks (“LANs”), one or more Metropolitan Area Networks (“MANs”), one or more Wide Area Networks (“WANs”), one or more Intranets, etc. Embodiments may also be practiced in distributed computing environments where tasks are performed by local and remote processing devices that are linked (either by hardwired links, wireless links, or by a combination thereof) through a communications network, e.g. in the “cloud.” In a distributed computing environment, program modules may be located in both local and remote memory storage devices. [0066] Other embodiments and uses of the invention will be apparent to those skilled in the art from consideration of the specification and practice of the invention disclosed herein. All references cited herein, including all publications, U.S. and foreign patents and patent applications, are specifically and entirely incorporated by reference. It is intended that the specification and examples be considered exemplary only with the true scope and spirit of the invention indicated by the following claims. Furthermore, the term “comprising of” includes the terms “consisting of” and “consisting essentially of.”

Embodiments of the invention are directed to methods and devices for displaying trends and variability in a physiological dataset. The method comprises obtaining the physiological dataset, applying a smoothing algorithm to the physiological dataset to obtain a trend of the physiological dataset, applying a variability algorithm to the physiological dataset to obtain the variability of the physiological dataset, outputting a graph of the trend of the physiological dataset, and outputting a graph of the variability of the physiological dataset.

CROSS-REFERENCE TO RELATED APPLICATIONS The present application claims priority to U.S. Provisional Application No. 61/222,296 filed Jul. 1, 2009. BACKGROUND OF INVENTION The present invention is related to a capacitor exhibiting high capacitance per unit volume. More specifically, the present invention is related to an improved conductive inner electrode design which improves electrode overlap, and therefore capacitance, with high voltage rating and no arc-over. Traditional high voltage capacitor designs, such as for use at ≧500Vdc, typically combine 2 or more capacitors in series within the same multilayer ceramic device package. These serial designs are effective at increasing effective voltage since the effective voltage is divided between the 2 capacitors. Capacitors arranged in series are also effective in decreasing the occurrence of surface-arc-over. Unfortunately, the effective capacitance, C eff , of a serial device is significantly lowered since 1/C eff =Σ1/C n where n is the number of capacitors in series. The practitioner has therefore had to balance the desire for high voltage capability, which can be improved by serial capacitors, with the desire for high capacitance, which is compromised with serial capacitors. For voltages up to about 2,500 Vdc the capacitance can be increased with minimal flash over by coating the capacitors themselves, or the board or assembled device, using standard MLCC designs. In the case of the individual monolithic multilayer capacitors the leads are attached and the part epoxy coated. A significant disadvantage to this approach is that the leaded part cannot typically be used in an automated surface mount assembly process and there is some additional cost associated with the leads and epoxy. One approach to mitigate the problem associated with flashover is described in U.S. Pat. No. 6,134,098 wherein lower K dielectric layers are used on the top and bottom of a series capacitor design. Although this approach is effective to decrease flash over this is still a serial capacitor design and the effective capacitance is lower as detailed above. Furthermore, differences in the thermal expansion coefficient of the various materials are problematic since thermal stresses are created during firing. Japanese Patent Abstract 2006-066831 by SHIMIZU MICHINAO, ITO KAZUNORI and KOMATSU TOSHIAKI discloses a multilayer ceramic capacitor design which raises the starting voltage of the surface discharge. To achieve this effect a serial type arrangement of capacitors, using multiple internal electrode prints, is required. Coating of parts whilst retaining the ability to surface mount can retard arc over. U.S. Pat. No. 6,627,529, by Duva and related U.S. Pat. No. 6,683,782, both of which are incorporated herein by reference, describe the benefits, and method, for applying para-xylylene polymer coatings to multi-layer ceramic capacitors. Coating individual parts, or the final assemblies, is cost prohibitive so these approaches have been restricted to high value added applications in electronics. Capacitance, C, is defined by the following equation; C=∈ r ∈ 0 An/t; where ∈ r is the relative permittivity of the dielectric; ∈ 0 is a constant equal to the permittivity of free space; A is the overlap area for each internal conductive layer, also referred to as an active; n is the number of actives and t is the separation distance or thickness between the electrodes. Therefore, it is an ongoing desire to increase the number of layers and overlap area while decreasing the layer separation. Often the efforts to increase voltage are contrary to one, or more of these desires. For example, in a more recent approach presented in U.S. Pat. No. 7,336,475 by Bultitude et al, which is incorporated herein by reference, shield electrodes are used which allow for a high voltage capability by prohibiting surface-arc-over whilst retaining a relatively high overlap area for high capacitance in a non-serial design. This design combines a top and bottom shield electrode that protects the oppositely charged electrode below from arc-over from the terminal in contact with the shield. Side shields are also described which function in a similar manner by protecting each active electrode along the side of the part by connecting to the terminal of opposite polarity while overlapping the active electrode to prevent arc over. US Pat. Publ. No. 2009/0052111 also to Bultitude, the entirety of which is incorporated by reference, describes the use of a coating of polyimide applied by spin coating to further increase voltage breakdown. Related US Pat. Publ. No. 2009/0052112, the entirety of which is incorporated by reference, describes the need to shield between the terminal and the opposed electrode. In both cases the MLCC designs described use side shields connected to the opposed terminal. The presence of side shields connected to the opposite terminal in each of the active layers confers a risk of a breakdown pathway between the shields and the active electrode. This pathway may occur due to contamination or electrode “bleed out” during the electrode printing process that would result in a short circuit and catastrophic failure of the capacitor. Furthermore, although the prior art designs have more overlap, and therefore higher capacitance, than the serial designs the side shields take-up a significant area which does not contribute to capacitance. The area occupied by the side shields decreases the available capacitance as a function of total volume since the area occupied by the shields can not be utilized for electrode overlap. In spite of the advances in the art there is still a long standing desire for a capacitor with improved capacitance, for use in high voltage applications, which has minimal flashover. Such a capacitor is provided herein. SUMMARY OF THE INVENTION It is an object of this invention to provide a capacitor with reduced flashover, also called surface-arc-over, without the need for another type of dielectric with potential thermal mismatch issues between different dielectrics whilst maintaining a high capacitance. It is another object of the invention to provide a capacitor with improved capacitance, per unit volume, without loss of effective voltage rating and with decreased flashover. These and other inventions, as will be realized an improved capacitor. The capacitor has first internal conductors and second internal conductors in an alternating layer wherein the first internal conductor has a first polarity and the second internal conductor has opposing polarity. A first external termination is in electrical contact with the first internal conductors wherein the first external termination has a first side extension which extends a distance along a side of the capacitor which is perpendicular to the first internal conductors and the second internal conductors. A second external termination is in electrical contact with the second internal conductors wherein the second external termination has a second side extension which extends a second distance along a second side of the capacitor which is perpendicular to the first internal conductors and the second internal conductors. The first internal conductors extend towards the second external termination to a separation distance from the second external termination which is less than the second distance. The first internal conductors comprise a bulk region and a secondary region wherein the secondary region has a region width which is less than a bulk width of the bulk region. Yet another embodiment is provided in an improved capacitor. The capacitor has first internal conductors and second internal conductors in an alternating layer wherein the first internal conductor has a first polarity and the second internal conductor has opposing polarity. A first external termination is in electrical contact with the first internal conductors wherein the first external termination has a first side extension which extends a distance along a side of the capacitor which is perpendicular to the first internal conductors and the second internal conductors. A second external termination is in electrical contact with the second internal conductors wherein the second external termination has a second side extension which extends a second distance along a second side of the capacitor which is perpendicular to the first internal conductors and the second internal conductors. The first internal conductors extend towards the second external termination to a separation distance from the second external termination which is less than the second distance. The first internal conductors comprise a bulk region and a secondary region wherein the secondary region is further from the second side extension than the second distance. Yet another embodiment is provided in a method of forming an multilayered ceramic capacitor. The method includes the steps of: printing a pattern of print regions of conductive material on a series of sheets wherein each print region has a bulk region and a secondary region wherein the secondary region has a region width which is less than a bulk width of the bulk region; forming a layered assembly by the steps of: overlaying a first sheet over a bottom sheet in parallel offset fashion wherein at least one print region of the bottom sheet is overlapped but laterally offset from a print region of the first sheet with a dielectric precursor between the overlapped but laterally offset print regions; overlaying a second sheet over the first sheet wherein at least one print region of the second sheet is overlapped but offset from the print region of the first sheet and the print region of the bottom sheet with a dielectric between the overlapped but laterally offset print regions; overlaying additional sheets with alternating sheets having the print region aligned with the first sheet and the second sheet respectively with a dielectric between the overlapped but laterally offset print regions, overlaying a top sheet with the print region aligned with the bottom sheet with a dielectric between the overlapped but laterally offset print regions; compacting and dicing the overlayed sheets to isolate a layered structure with print regions of the first layer forming first internal conductors; print regions of the second layer forming second internal conductors and print regions of the top sheet and the bottom sheet forming shield layers; firing the compacted and diced overlayed sheets to remove organic materials and fuse the overlayed sheets into a fired monolith; forming a first external termination in electrical contact with the first internal conductors; and forming a second external termination in electrical contact with the second internal conductors. BRIEF DESCRIPTION OF FIGURES FIG. 1 is a schematic cross-sectional view of a capacitor. FIG. 2 is a schematic cross-sectional view of a capacitor taken along line 2 - 2 of FIG. 1 . FIG. 3 is a schematic cross-sectional view of a capacitor. FIGS. 4A-4F are schematic representations of conductive inner electrodes. FIG. 5 is a schematic representation of an active electrode print. FIG. 6 . is a schematic representation of an top and bottom shield electrode print. FIG. 7 is a schematic representation of an active electrode print. FIG. 8 is a schematic representation of an active electrode print. FIG. 9 is a schematic representation of an active electrode print. FIG. 10A-F are schematic representations of conductive inner electrodes. FIG. 11 is a schematic representation of an active electrode print. FIG. 12 is a schematic cross-sectional view of a capacitor. FIG. 13 is a schematic cross-sectional view of the capacitor of FIG. 11 taken along line 13 - 13 . FIG. 14 is a schematic cross-sectional view of the capacitor of FIG. 11 taken along line 14 - 14 . FIG. 15 is a schematic representation of an active electrode print. DETAILED DESCRIPTION The present invention is directed to an improved capacitor. More specifically, the present invention is directed to a capacitor with improved geometry of inner conductive layers. The invention will be described with reference to the various figures which are an integral non-limiting component of the disclosure. Throughout the figures similar elements will be numbered accordingly. For simplicity, a minimal number of active layers is illustrated with the understanding that the actual number used may be quite large. A cross-sectional schematic view of a multi-layer ceramic capacitor of the present invention is illustrated schematically in FIG. 1 . In FIG. 1 , the capacitor, generally represented at 10 , comprises a multiplicity of conductive inner electrodes, 11 and 12 , of alternating polarity with dielectric ceramic layers, 15 , dispersed there between. The alternating conductive inner electrodes terminate at opposing external terminals, 13 and 14 . An insulating layer, 16 , may be applied. A cross-sectional schematic view of the capacitor of FIG. 1 taken along line 2 - 2 is provided in FIG. 2 . In FIG. 2 , an arc point exist as the closest point between the side extension, 17 , of the external termination, 14 , and the closest extent, 18 , of the conductive inner electrode, 11 , of opposing polarity. An embodiment of the invention is illustrated in cross-sectional schematic view taken parallel to the inner electrodes in FIG. 3 . In FIG. 3 , a first conductive inner electrode, 111 , is in electrical contact with an external termination of common polarity, 113 . A second conductive electrode, 112 , is also in electrical contact with an external termination of common polarity, 114 , with the first and second conductive inner electrodes being of opposing polarity as would be realized. Dielectric, 115 , is between and around the conductive electrodes. An insulating layer, 116 , may be applied. For the purposes of discussion the first conductive inner electrode and second conductive inner electrode are of the same shape and size. Different shapes and sizes are functional yet for manufacturing purposes it is highly desirable that they be the same since each is designed to be as large as possible within the constraints of avoiding flashover as will be more fully described. In the discussion, conductive inner electrode will refer to one layer or both layers. The inner conductive layer is defined as having a bulk zone, 120 , which is most preferably rectangular, and a secondary zone, 121 . The bulk zone and secondary zone are defined for the purposes of geometry and taken together they form a seamless inner conductive layer preferably with no difference in layer thickness or composition. At least a portion of the secondary zone is a distance, D 1 , from the external termination of opposing polarity than the and a distance, D 2 , is the distance the external termination side extension, 117 , extends along the side away from the external termination. The bulk zone, 120 , preferably is as large as possible to provide the most overlap with the inner conductive layer of opposing polarity. The secondary zone, 121 , comprises a region which has a width which is narrower than the width, W, of the bulk zone. The narrowed region of the secondary zone insures that the closest distance between the external termination side extension, 117 , and the narrowed portion, 118 , of the secondary zone is at least as large as the closest separation distance between the conductive inner electrode and external termination of opposing polarity, represented as D 1 . The height of the bulk zone, H, is preferably at least 66% of the longest length of the inner conductive layer measured from the contact point with the exterior termination of common polarity. A height of the bulk zone of as low as 25% has been demonstrated successfully. Representative conductive inner electrodes are illustrated schematically in FIGS. 4A-4F wherein each conductive inner electrode, 111 , is illustrated with a rectangular bulk zone, 120 , and a secondary zone, 121 . In FIG. 4A , the secondary zone comprises a semiround shape. The semiround shape can have the same radius over the entire zone thereby forming a semicircle. Alternatively, the radius can vary thereby forming a semi-oval shape or a semi-obround shape wherein an obround shape consist of two semicircles connected by parallel lines tangent to their endpoints. In FIG. 4B the secondary zone comprises a partially rounded rectangular shape. The rounded portions may have the same radius over the entire round zone thereby forming a semicircle or the radius can vary thereby forming a semi-oval shape or a semi-obround shape. In FIG. 4C the secondary zone is trapezoidal with the shorter parallel face preferably opposite to the bulk zone. In FIG. 4D the secondary zone is rectangular with a length, L, which is less than the width, W, of the bulk zone. In FIG. 4E the secondary zone is a concave trapezoid wherein the non-parallel sides of a trapezoid are concave. The concave shape is preferably rounded and may have the same radius over the entire round zone thereby forming a semicircle or the radius can vary thereby forming a semi-oval shape or a semi-obround shape as described relative to FIG. 4A . In FIG. 4F the secondary zone is a combination with a first secondary zone being trapezoidal and the second secondary zone being semiround. In the secondary zone the radius of any rounded portion is sufficiently large that the separation between the closest extent of the external termination side extension and the inner conductive electrode is larger than the separation between the secondary portion and the external termination of opposing polarity. The dielectric ceramic layers preferably comprise a dielectric ceramic composition. The major constituent material for the ceramic, for example, may be made of BaTiO 3 , BaCaTiZrO 3 , BaCaZrO 3 , BaZrO 3 , CaZrO 3 and/or CaTiO 3 but the current invention is not particularly limiting to the type of ceramic dielectric material used and other dielectric materials, insulators, magnetic materials and semiconductor materials, or combinations thereof, as known in the art. The dielectric ceramic composition can be used in conjunction with precious metal or base metal inner electrodes. Cheaper base metal electrodes are most preferred and they require a non-reducible ceramic which can be sintered in a reducing atmosphere below the melting temperature of common base metals, such as nickel, without detriment to the electrode thereby yielding a capacitor with high electrode continuity and excellent electrical properties. The conductive inner electrodes comprise precious metal or base metal. Common base metals include nickel, tungsten, molybdenum, aluminum, chromium, copper or an alloy thereof which can be fired in a reducing atmosphere. Common precious metals are silver, palladium, platinum, gold or alloys thereof. Most preferably the base metal is nickel. The composition of the external terminations and side extensions is not particularly limiting herein and any composition typically employed in the art is sufficient. Silver, palladium, copper, nickel or alloys of these metals compatible with the inner electrodes blended with various glass frits are particularly relevant. A plating layer or multiple plating layers can be formed on the external end terminations. Because of the use of base metals in the conductive inner electrodes, the capacitor of the present invention is preferably fired in a reducing atmosphere. The reducing overall atmosphere average PO 2 is preferably between 10 −3 to 10 −18 atm, while the PO 2 in localized regions within the capacitor monolith have been estimated to be as low as ˜10 −28 atm (C. A. Randall, et al., “A Structure-Property-Processing Approach Targeted to the Challenges in Capacitive Ceramic Devices,” CARTS USA 2006 PROCEEDINGS, at 3-12, Apr. 3-6, 2006). An advantage of the present invention is the ability to use the same materials commonly employed and the conventional tape casting process familiar to those skilled in the art. In this process the ceramic powder, such as the preferred base metal compatible X7R dielectric comprising a substantial portion of barium titanate, is dispersed in an organic medium then cast into a tape. Some of the tape is printed with the electrode pattern, in this case a paste of nickel in organic medium. Merely as an example of the manufacturing process of the present invention, a ceramic slurry is prepared by blending and milling the ceramic compounds of choice with a dispersant in either water or an organic solvent such as, for example, ethanol, isopropanol, toluene, ethyl acetate, propyl acetate, butyl acetate or a blend thereof. After milling a ceramic slip is prepared for tape-casting by adding a binder and a plasticizer to control rheology. The slip is then processed into a thin sheet by tape-casting. After drying the sheet, a multiplicity of electrodes are patterned on the sheet by using, for example, a screen-printing method to form a printed ceramic sheet. A laminate green body is prepared by stacking onto a substance such as polycarbonate, polyester or a similar method: 1) a certain number of unprinted ceramic sheets representing the bottom covers, then 2) a certain number of printed ceramic sheets in alternate directions so as to create alternating electrodes that terminate at opposing ends, and 3) a certain number of unprinted ceramic sheets representing the top covers. Variations in the stacking order of the printed and unprinted sheets can be used with the dielectric material of this invention. The stack is then pressed at between 20° C. and 120° C. to promote adhesion of all laminated layers. The laminated green body is then cut into individual green chips. Capacitors made with precious metal inner electrodes can be sintered in air up to temperatures not exceeding 1400° C. In the case of base metals the ceramic is then sintered in a reductive atmosphere with a partial oxygen partial pressure of 10 −3 to 10 −18 atm at a temperature not to exceed approximately 1500° C. The sintered capacitor is preferably subjected to end surface grinding by barrel or sand blast, as known in the art, followed by applying external electrode paste to form the terminations to the inner electrode. A further firing is then done to complete the formation of the termination. For precious metal electrodes this firing is typically done in air at temperatures of about 500° C. to 900° C. For base metals this firing is typically done in nitrogen atmosphere at a temperature of about 600° C. to 1000° C. for about 0.1 to 1 hour. Layers of nickel and tin may then be plated on the outer electrodes to enhance solderability and prevent oxidation of the outer electrodes. A particularly preferred embodiment of the invention is illustrated in FIGS. 10A-10F wherein each electrode has a bulk region, 120 , and a secondary region, 121 , as illustrated in FIGS. 4A-F and described relative thereto. In FIGS. 10A-10F a tertiary region, 121 ′, is provided which is preferably identical to the secondary zone in shape and size. The secondary zone and tertiary zone can be different in shape and size but this is highly undesirable due to increases in manufacturing complexity as will be better understood from the discussion which follows. The advantage of a symmetrical electrode, as described relative to FIGS. 10A-10F will be discussed with reference to FIG. 11 . In FIG. 11 a conductive region is illustrated, for convenience, having a rectangular bulk region and symmetrically disposed trapezoid secondary and tertiary regions. A sheet, 700 , is prepared with a multiplicity of identical print zones, 701 , thereon. It is preferred that each print zone is separated a distance, S, from the adjacent print zone as measured between the narrowed ends. In practice, the distance S needs to be sufficiently large to avoid any shorting or arching between subsequent print regions. A separation of at least 0.20 mm (0.008 inches) is satisfactory. An advantage of this design is that the top and bottom shield electrodes and electrodes with both polarities can be made from a common print. This eliminates the necessity for multiple print patterns and greatly improves manufacturability. By way of example, the sheet can be cut along line, 702 and 702 ′, wherein each half of the illustrated print zone will function as a shield electrode in the finished product as will be more clearly realized with reference to FIGS. 12-14 and discussion thereof. Similarly, the sheet can be cut along line, 703 and 703 ′, which is intended to just separate the print zone, to form an active layer of a first polarity by being attached to an external termination at the cut line. Similarly, the sheet can be cut along line, 704 and 704 ′, to form an active layer of a second polarity. Cut line 702 and 702 ′ are preferably centered within the print zone whereas cut lines 703 , 703 ′; 704 and 704 ′ are preferably just inside of the print zone thereby insuring adequate contact with the eventual external termination. The layers are cut along lines 705 and 705 ′ to isolate individual capacitive units. A capacitor formed utilizing the symmetrical electrode of FIG. 11 is illustrated in cross-sectional side view in FIG. 12 . FIG. 13 is a cross-sectional view of the capacitor of FIG. 12 taken along line 13 - 13 and FIG. 14 is a cross-sectional view of the capacitor of FIG. 12 taken along line 14 - 14 . In FIGS. 12-14 , the active electrodes, 1111 and 1112 , are of opposing polarity with alternate active electrodes in electrical contact with opposing external terminations, 1113 and 1114 . Tabs, 1019 , are remnants of the cut pattern as realized from the cut patterns illustrated in FIG. 15 . The tabs are not particularly preferred but are an artifact of the cutting operation. The shield electrodes, 1011 , 1012 , 1013 and 1014 , are disposed on each face, parallel to the active electrodes. Shield electrodes 1012 and 1013 are functional shields which protect the adjacent active electrode from arcing to the external termination in closest proximity. Shield electrodes, 1011 and 1014 , are optional electrodes provided for manufacturing convenience as understood in the art. The optional insulating layer, 1116 , is as discussed above. The shield electrodes are separated by a distance, S, which corresponds to the separation of the print zones as described relative to FIG. 11 . As would be realized from the discussion relative to FIGS. 11-14 the symmetrical electrode pattern allows for a single pattern to be used for shield electrodes, and both actives, by merely shifting adjacent sheets in a parallel arrangement. This greatly simplifies sheet placement during capacitor manufacture and any sheet can function for any layer within the capacitor thereby minimizing the number of different parts which must be manufactured. EXAMPLES The following examples use tapes made of the same material and with the same fired thickness of 0.001″ (25.4 μm). All of the parts utilized a 1206 case size manufactured with the same materials by the same process the only factor affecting the electrical properties is the overlap area A which is a function of the design of the internal conductive electrode. No coatings were applied to these capacitors. Conductor designs are described in more detail in Table 1 and in the examples. TABLE 1 Top & Total Number of Active or Intermediate Bottom Shield Example Electrode Prints Active Electrode Prints Electrode Prints 1 40 40 0 2 42 40 2 3 42 40 2 4 42 40 2 5 42 40 2 6 42 40 2 7 42 40 2 8 42 40 2 Comparative Example 1 A basic MLCC was manufactured using the active overlap pattern shown in FIG. 5 wherein for adjacent sheets the areas in the window overlap as would be realized by one of skill in the art. Comparative Example 2 A similar active design was used to the design described in Example 1 above accept that additional first and last prints were added with a top and bottom shield electrode pattern with the intermediate actives identical to those described in Example 1. This top and bottom shield electrode pattern is shown in FIG. 6 by overlaying the part area in the window with a window of the printed tape of FIG. 5 . Comparative Example 3 In addition to using the top and bottom shields described in Example 2 the side shields were used in the intermediate actives as shown in FIG. 7 below. Furthermore, in order to maximize the available overlap area, and so achieve the highest possible capacitance, only 2 side shields are employed. It can also be seen that since the side shields are connected to the opposite terminal of the capacitor breakdown caused by a low insulation pathway between a side shield and active would result in a short circuit and catastrophic failure. Inventive Examples 4-7 Top and bottom shields as described in Examples 2 and 3 were used but there are no side shields in the active layers as described FIG. 7 above. The inventive internal conductors eliminate the requirement for side shields by using secondary zones of the electrode to increase the distance from the termination of opposite polarity and the end of the conductive inner layer. Although the tapering decreases the available overlap area compared to Examples 1 and 2 it still achieves a higher electrical breakdown than either of these examples whilst retaining a higher capacitance in all cases compared to Example 3. The dimensions, after firing, used in the inventive electrode designs of Examples 4, 5, 6 and 7 are summarized in Table 2 with reference to FIG. 8 . In this way capacitance can be maximized whilst retaining a high voltage breakdown as noted in the electrical properties shown in Table 3. TABLE 2 Example A 4 (mm) A 4 (inches) D 4 (mm) D 4 (inches) 4 0.998 0.0393 0.500 0.0197 5 2.02 0.0795 0.500 0.0197 6 0.998 0.0393 0.813 0.0320 7 2.02 0.0795 0.813 0.0320 Inventive Example 8 A semi-circle tapered design was used at the end of the electrode. In this case the maximum extent of the electrode (A 4 ) is 2.02 mm (0.0795 inches), after firing, which is the same as examples 5 and 7. The intermediate active prints are shown in FIG. 9 . The electrical properties of Examples 1-8 are summarized in Table 3. TABLE 3 Capacitance and Voltage Breakdown Dissipation Factor - 50 pcs in Air - 50 pcs (VDC) 48 hr Cap Cap Std Dev Cap % Std 48 hr Df Df Std Dev Std. Example Mean (nF) (nF) Dev Mean (%) (%) Avg. Max. Min. Dev. 1 137.48 0.86 0.63% 1.42 0.039 972 1350 730 146 2 141.00 1.44 1.02% 1.48 0.024 1347 1720 1060 156 3 81.01 0.74 0.91% 1.47 0.015 1712 2140 1120 224 4 85.34 0.55 0.64% 1.49 0.010 1504 2070 1150 203 5 98.21 0.86 0.88% 1.35 0.029 1653 1860 1270 118 6 98.09 1.44 1.47% 1.41 0.028 1635 1860 1210 166 7 109.06 0.74 0.68% 1.44 0.022 1635 1840 1350 138 8 107.37 0.63 0.58% 1.46 0.027 1603 1830 1150 188 This electrical data shows the average capacitance of an MLCC made with the design described in Examples 4, 5, 6, 7 and 8 are higher than in comparative Example 3. Example 4 has a capacitance of 85.34 nF compared to 81.01 nF for the patented design in Example 3. Example 4 has 5.3% more capacitance than Example 3. Table 3 shows the standard deviations (σ) associated with these capacitance measurements. The 3σ associated with Examples 3 and 4 are 2.22 nF and 1.65 nF, respectively, and since the increased capacitance of 4.33 nF is higher than the combination of these (3.87 nF) the results are significant. The minimum voltage breakdown for Examples 4, 5, 6, and 7 are higher, in all cases, than the minimum of 1120 V recorded for Example 3. The minimum voltage breakdown is a good indicator of the design capability so the new designs disclosed in Examples 4, 5, 6, 7 and 8 offers an increased capacitance over Example 3 with similar voltage capability. The present invention provides capacitors with a break down voltage of over 1120 volts. It should also be noted that although Examples 1 and 2 have the highest capacitance their voltage breakdowns are lower than all the other examples. Furthermore, it can be seen that the highest minimum breakdown voltage was 1350 V for Example 7, the highest capacitance obtained for the inventive design that is 34.6% higher capacitance than Example 3. The semi-circle electrode pattern described in Example 8 has a similar capacitance to Example 7 but the Average, Maximum and Minimum UVBD are all slightly less for Example 8. Inventive Examples 9-12 Four batches of MLCC were manufactured with the electrode pattern of FIG. 15 used for each layer. In FIG. 15 , the top and bottom shield layers were ultimately formed by cutting the pattern shown in cut box 1501 . A first polarity active terminal, and related tab, were ultimately formed by cutting the pattern shown in cut box 1502 and a second polarity active terminal, and related tab, were ultimately formed by cutting the pattern shown in cut box 1503 . The fired thickness of each layer was 25.4 μm (0.001 inch). Each MLCC was formed using 44 layers. The electrical properties of each batch are provided in Table 4. TABLE 4 Capacitance and Dissipation Factor - 50 pcs Cap Std Cap % 48 hr Df Voltage Breakdown 48 hr Cap Dev Std Mean Df Std in Air - 50 pc Example Mean (nF) (nF) Dev (%) Dev (%) Avg. Max. Min. Std. Dev. 9 95.57 1.58 1.65% 1.24 0.013 1781 2140 1330 256 10 95.71 1.04 1.09% 1.24 0.012 1846 2170 1420 202 11 94.13 0.99 1.06% 1.10 0.013 1810 1930 1590 100 12 94.85 0.87 0.92% 1.10 0.014 1837 2050 1690 103 As can be realized from the data presented in Table 4, a single electrode pattern provides a high capacitance with a high breakdown voltage which is otherwise unavailable. The capacitance values exceed those presented in Example 3 of U.S. Pat. No. 7,336,475 even allowing for the additional capacitance attributable to and additional 2 electrode prints which are used as shields. A single pattern would not be useable in the teachings of U.S. Pat. No. 7,336,475 due to the formation of gaps in the top and bottom shields. High voltage capacitor designs are demonstrated herein that provide higher capacitance and increased voltage handling capability than currently available in the prior art. The invention has been described with particular reference to preferred embodiments without limitation thereto. One of skill in the art will realize additional alterations, embodiments and examples which are not specifically set forth but which are within the meets and bounds of the invention as more specifically set forth in the claims appended hereto.

New designs for multilayer ceramic capacitors are described with high voltage capability without the need of coating the part to resist surface arc-over. One design combines a high overlap area for higher capacitance while retaining a high voltage capability. A variation of this design has increased voltage capability over this design as well as another described in the prior art although overlap area and subsequently capacitance is lowered in this case. These designs are compared to the prior art in examples below.

BACKGROUND OF THE INVENTION Directional microphones are an effective way to facilitate the comprehension of voice in an environment full of interfering sound since they have a sensitivity depending on the direction of the incidence of sound (directional pattern) and, thus, produce a spatial suppression of interfering sounds. Directional pattern or directional effect describes the ratio of the sensitivities of a microphone to sound sources impinging on the microphone from all directions of one plane and essentially depends on the construction of the microphone. Known directional patterns are spherical or omnidirectional, figure-of-eight or bidirectional, cardioid, supercardioid, hypercardioid and lobe pattern. The spherical pattern is distinguished by the fact that the sound is picked up with the same strength from all directions. A microphone having a spherical pattern is, for example, the “pressure transducer”, the diaphragm of which, only the front of which is exposed to the sound field, picks up all pressure fluctuations located in the sound field regardless of the direction from which they come. Since this microphone does not have a preferred directional effect, it has a spherical pattern and is frequently called a “spherical microphone”. A figure-of-eight pattern is distinguished by the fact that the sound is picked up with particular intensity from two selected directions which are opposite to one another. Microphones having a figure-of-eight pattern, also called “figure-of-eight microphones”, have been developed for, among other things, the M/S stereo method and enable the stereo base to be subsequently influenced right up to mono. A microphone having a figure-of-eight pattern is, e.g., the “pressure-gradient transducer” or “pressure-difference transducer” which is designed in such a way that the sound reaches the diaphragm both from the front and from the back, which requires two sound entry openings so that the diaphragm is not deflected when sound arrives from the side and a “figure-of-eight” directional pattern is guaranteed. A further possibility of achieving a figure-of-eight pattern which, moreover, is more flexible than the purely mechanical arrangement of the pressure-gradient transducer, is an arrangement of two simple spherical microphones which are slightly offset in space (array). The directional effect is obtained by electronically subtracting the spherical-microphone signal at the front (from the point of view of the incident sound) from the delayed signal of the spherical microphone at the rear. The precise shape of the directional pattern is defined by the microphone spacing and the internal electrical delay. The pressure-difference or pressure-gradient transducer supplies a signal proportional to cos(α) with a sound incident at an angle α and is, therefore, a directional microphone having a first-order directional pattern. Dispensing with close-talking microphones in telephones, in video conferences or in automatic voice recognition leads to reverberation and background noises becoming superimposed on voice. These unwanted signal components are compensated for by using a directional microphone having one of the patterns mentioned above, particularly via a controllable (directional-) microphone array, the main lobe of which is focused on the speaker, typically automatically. In this context, “controllable” refers to the direction (orientation) of the main lobe, which is determined by an angle (φ) which is preset or automatically orientated toward a speaker by methods of localization and voice detection (i.e., is variable), being adjustable by, in particular digital, signal postprocessing of the received signals generated by the directional microphones from an incident sound. Therefore, a controllable first-order directional microphone is obtained in a familiar manner when a signal generated by a first-order directional microphone (e.g., pressure-difference transducer) is postprocessed via signal processing so that a desired direction (φ) of the main lobe is imparted to the signal and, finally, a signal results which is proportional to cos(φ+α). However, directional-microphone arrangements with a second-order directional pattern, particularly controllable directional-microphone arrangements, are not known. An object of the present invention is, therefore, to specify a system and a method which ensure a, particularly controllable, second-order directional-microphone pattern. SUMMARY OF THE INVENTION Accordingly, in an embodiment of the present invention, a directional-microphone system is provided which includes: a first directional microphone with a figure-of-eight pattern (“figure-of-eight microphone”) and a second figure-of-eight microphone which are arranged in such a manner that the major axis of the first figure-of-eight microphone and the major axis of the second figure-of-eight microphone extend in parallel with a first axis; a third figure-of-eight microphone and a fourth figure-of-eight microphone, which are arranged in such a manner that the major axis of the third figure-of-eight microphone and the major axis of the fourth one extend in parallel with a second axis, the first axis and the second axis being orthogonal to one another; a fifth figure-of-eight microphone which is arranged in such a manner that the major axis of the fifth-figure-of-eight microphone extends orthogonal to the major axis of the first figure-of-eight microphone; and a device for phase shifting which is connected downstream of the second figure-of-eight microphone and third figure-of-eight microphone. This system ensures that, with a minimum number of directional microphones, received signals which are at least almost proportional to sin(α), cos(α), sin(α)*cos(α), cos 2 (α) or sin 2 (α), are generated from a sound wave which comes from a direction with the angle α (referred to the first axis); i.e., both first-order directional microphones (received signal proportional to cos(α)) and second-order directional microphones (received signal proportional to cos 2 (α)) are implemented, the filter arrangement equalizing any phase shift. In addition, the system only needs little space since the distance between the first figure-of-eight microphone and the second figure-of-eight microphone and the distance between the third figure-of-eight microphone and fourth figure-of-eight microphone is of the order of magnitude of 3 cm. In a method according to the present invention: a) a first arrangement of two figure-of-eight microphones with mutually parallel major axes are driven in such a manner that a first received signal proportional to A*cos 2 (α) is obtained; b) a second arrangement of two figure-of-eight microphones with mutually parallel major axes are driven in such a manner that a second received signal proportional to B*sin 2 (α) is obtained; c) a fifth figure-of-eight microphone with a major axis orthogonal to a figure-of-eight microphone of the first figure-of-eight microphone arrangement or a figure-of-eight microphone of the second figure-of-eight microphone arrangement is driven in such a manner that a third received signal proportional to C*cos(α)*sin(α) is obtained; d) a figure-of-eight microphone of the first figure-of-eight microphone arrangement and figure-of-eight microphone of the second figure-of-eight microphone arrangement, the major axes of which extend orthogonal to one another, are driven in such a manner that a fourth received signal proportional to D*cos(α)+E*sin(α) is obtained; and e) the fourth received signal is phase-shifted by 90° and linearly combined with the sum of the first received signal, the second received signal and the third received signal, setting A:=cos 2 (φ) B:=sin 2 (φ) C:=−2 cos(φ)*sin(φ) D:=cos(φ) E:=−sin(φ), and where α:=the direction from which a sound wave is coming φ:=desired direction of the major lobe. An advantage of the method according to the present invention is the simple implementation of a controllable directional pattern which at least approximately corresponds to a second-order directional pattern, the partial multiple use or, respectively, signal processing of individual received signals generated by the figure-of-eight microphones due to a sound incident at α having the result that a minimum number of figure-of-eight microphones is sufficient for generating a second-order directional pattern. In addition, a first-order directional pattern is also generated via this method (fourth received signal) so that optionally the first- or second-order directional pattern can be selected as required and the first- and second-order directional pattern also can be selected in combination so that, overall, it is possible to generate different shapes of directional patterns. In an embodiment, postprocessing of the received signals generated by the figure-of-eight microphones is provided depending on the use of the directional-microphone system. Thus, when it is used, for example, in systems where the sound to be received comes from a preferred direction, a major lobe direction (angle φ) is defined by signal processing performed by the control device, and in systems where the sound to be received does not have a preferred direction, a major lobe direction is set depending on the current direction of sound incidence via special algorithms of the signal processing. In an embodiment, received signals of more precise proportionality to cos(α)*sin(α) and cos 2(α), for which these directional microphones are responsible, can be generated. In an embodiment, received signals of more precise proportionality to cos(α) and −sin(α), for which these directional microphones are responsible, can be generated. In an embodiment, a simple form of a directional microphone is provided having a figure-of-eight pattern (figure-of-eight microphone). In an embodiment, a higher flexibility of the system with respect to the directional pattern is ensured since the figure-of-eight pattern is generated by two spherical patterns and, therefore, both figure-of-eight patterns and spherical patterns are available as required. In addition, this development has the advantage of a higher degree of freedom in the tuning of the system since the spherical microphones of the pairs of spherical microphones which, in each case, create a figure-of-eight microphone which can be repositioned. In an embodiment, a more precise formation of the second-order directional pattern is allowed since a signal component with spherical pattern is required for precisely generating such a second-order pattern, unless it is neglected, as is generally the case, in which case the spherical pattern can be achieved, for example, via a further development of the present invention. Additional features and advantages of the present invention are described in, and will be apparent from, the following Detailed Description of the Invention and the Figures. BRIEF DESCRIPTION OF THE FIGURES FIG. 1 shows a controllable directional-microphone system with five figure-of-eight microphones (abstract representation). DETAILED DESCRIPTION OF THE INVENTION FIG. 1 shows a first axis x 1 and a second axis x 2 . Furthermore, five directional microphones (figure-of-eight microphones) Mik 1 , Mik 2 , Mik 3 , Mik 4 and Mik 5 with figure-of-eight-shaped directional pattern (figure-of-eight pattern) can be seen, these figure-of-eight microphones in each case being formed by a pair of directional microphones with spherical pattern (spherical microphones) arranged to be offset, the figure-of-eight pattern being achieved by subtracting the signals generated by the individual spherical microphones of the pair of spherical microphones. As an alternative to the pairs of spherical microphones, other pressure-gradient transducers also can be used as figure-of-eight microphones, or a mixed form of the individual variants, in particular with pairs of spherical microphones; e.g., in the case where at least one spherical pattern is necessary. On the first axis x 1 , the first figure-of-eight microphone Mik 1 and, offset thereto, the second microphone Mik 2 are arranged in such a manner that their major axes extend in parallel, particularly almost coincident, with respect to the first axis x 1 . The major axis of the figure-of-eight microphones Mik 1 , Mik 2 , Mik 3 , Mik 4 and Mik 5 , shown in FIG. 1 , extends perpendicularly and centrally with respect to the pairs of spherical microphones. In the embodiment of the figure-of-eight microphones as pressure-gradient transducers, the major axis extends perpendicularly and centrally with respect to the diaphragm or, respectively, to the sound entry opening(s). This offset placement of the first figure-of-eight microphone Mik 1 and second figure-of-eight microphone Mik 2 on one axis results in a second-order directional-microphone arrangement because it supplies a received signal proportional to cos 2 (α) in the case of the incidence of a sound at the angle α (the first axis x 1 is assumed to be the reference axis for angles). On the second axis x 2 , the third figure-of-eight microphone Mik 3 and, offset thereto, the fourth figure-of-eight microphone Mik 4 are arranged in such a manner that their major axes in each case extend in parallel, particularly almost coincident with respect to the second axis x 2 . This placement also results in a second-order directional-microphone arrangement but generates a received signal proportional to sin 2 (α) in the case of the incidence of a sound at the angle α, the reference axis again being the first axis x 1 , since the second axis x 2 is orthogonal to the first axis x 1 . It is particularly when the second figure-of-eight microphone Mik 2 and the third figure-of-eight microphone Mik 3 are placed closely next to one another so that they come to be almost coincident, where, in particular, the centers of the microphones come to be almost coincident, that requirements for the space required for implementing a second-order directional-microphone arrangement are reduced to a minimum. In this arrangement, the centers are determined by the center of the line connecting the two spherical microphones if pairs of spherical microphones are used for implementing figure-of-eight microphones, or by the center of the diaphragm if other pressure-difference transducers are used. Due to this placement, with a sound incident at the angle α, a received signal proportional to cos(α) is generated by the second figure-of-eight microphone Mik 2 on the one hand, and, on the other hand, a received signal proportional to sin(α) is generated by the third figure-of-eight microphone Mik 3 . In particular, the fifth figure-of-eight microphone Mik 5 is placed in such a manner that it comes to be almost coincident with the first figure-of-eight microphone Mik 1 , in particular so that the centers (see above) come to be almost coincident. From this placement, a received signal proportional to cos(α)*sin(α) is obtained due to the offset of the first figure-of-eight microphone Mik 1 and the second figure-of-eight microphone Mik 2 in conjunction with the orthogonal relation of the second figure-of-eight microphone Mik 2 to the third figure-of-eight microphone Mik 3 with a sound incident at the angle α. The precise placement of the individual figure-of-eight microphones Mik 1 . . . Mik 5 , i.e. the respective offset spacing of the microphones on the respective axes x 1 , x 2 , if coincidence with the axes x 1 , x 2 or, respectively, the respective centers is given or if parallelism with respect to the axes x 1 , x 2 is given, depends on various parameters. For example, mainly, on tolerances of the microphones used or required accuracy of the directional pattern and, in addition, to a slight extent on the field of use to be expected (noise background, transfer function of the space) so that, lastly, it must be determined by simulation and/or test configurations in conjunction with suitable measurements, and slight variations are therefore possible. To achieve controllability of the figure-of-eight microphone arrangement described, the figure-of-eight microphones Mik 1 . . . Mik 5 are linked to a control device μP; for example, a microprocessor. In this context, controllability refers to the respective received signals of the individual figure-of-eight microphones Mik 1 . . . Mik 5 being processed further, preferably digitally, in such a manner that they are in each case associated with coefficients or factors depending on an angle φ, the angle φ (also referred to the first axis x 1 ) being the desired orientation of the major lobe. The decision whether the orientation is predefined or should be variable depends on the planned type of use of a directional-microphone system and is reflected in the algorithms used for defining the orientation φ. Furthermore, the control device drives the figure-of-eight microphone system described in such a manner that it now implements a controllable first-order directional-microphone system and/or a controllable second-order directional-microphone system. A directional-microphone system with a general second-order directional pattern is achieved via an output signal of the system which is proportional to K+L *cos(α+φ)+ M *cos 2 (α+φ) where the term (coefficient) K is obtained by a signal having a spherical pattern, the term L*cos(α+φ) is obtained with a signal having a first-order figure-of-eight pattern and the term M*cos 2 (α+φ) is obtained with a signal having a second-order figure-of-eight pattern and where the term K is generally negligible so that it is essentially sufficient to generate a first-order figure-of-eight pattern and a second-order figure-of-eight pattern. For a first-order figure-of-eight pattern, therefore, the system is driven in a method step in such a manner that two of the figure-of-eight microphones Mik 1 . . . Mik 5 are selected which, with a sound incident at α, generate received signals, one of which is proportional to cos(α) (third figure-of-eight microphone Mik 3 ) and one of which is proportional to sin(α) (second figure-of-eight microphone Mik 2 ), these received signals being combined linearly in accordance with the following formula D *cos(α)+ E *sin(α). To obtain a shape proportional to cos(α+φ), the factor D=cos(φ) and the factor E=−sin(φ) are now generated in a signal processing step so that, according to the theorem of addition cos( x+y )=cos( y )*cos( x )−sin( y )*sin( x ) the signal (fourth received signal) cos(α+φ)=cos(α)*cos(α)−sin(φ)*sin(α) is obtained. To generate a second-order figure-of-eight pattern, therefore, in a further method step two further figure-of-eight microphones (first figure-of-eight microphone Mik 1 and second figure-of-eight microphone Mik 2 ) of the figure-of-eight microphones Mik 1 . . . Mik 5 are selected which generate a first received signal which is proportional to cos 2 (α) with the sound incident at α, and the third figure-of-eight microphone Mik 2 and fourth figure-of-eight microphone Mik 4 are selected which generate a second received signal proportional to sin 2 (α) in conjunction with one another. Furthermore, the third figure-of-eight microphone Mik 3 and the fifth figure-of-eight microphone Mik 5 are selected which generate a third received signal proportional to sin(α)*cos(α) in conjunction with one another. The first, second and third received signal are then combined in a signal processing step according to the following formula A *cos 2 (α)+ B *sin 2 (α)+ C *cos(α)*sin(α). To obtain a signal according to cos 2 (α+φ), the factors A, B and C are developed by signal processing, using the theorem of addition cos 2 ⁡ ( x + y ) = ⁢ [ cos ⁡ ( y ) * cos ⁡ ( x ) - sin ⁡ ( y ) * sin ⁡ ( x ) ] 2 = ⁢ cos 2 ⁡ ( y ) * cos 2 ⁡ ( x ) - 2 * sin ⁡ ( y ) * sin ⁡ ( x ) * cos ⁡ ( y ) * ⁢ cos ⁡ ( x ) + sin 2 ⁡ ( y ) * sin 2 ⁡ ( x ) in the following manner A=cos 2 (φ) B=sin 2 (φ) C=−2*sin(φ)*cos(φ), resulting in the second-order figure-of-eight pattern according to cos 2(φ+α). Lastly, in order to implement the controllable directional-microphone system having a general second-order directional pattern, a phase shift by 90°, which exists between the first-order figure-of-eight pattern and the second-order figure-of-eight pattern, is firstly equalized via a device (for example, a Hilbert filter) which is connected downstream of the second figure-of-eight microphone Mik 2 and the third figure-of-eight microphone Mik 3 , so that a fifth received signal is produced, and then the first, second, third and fourth received signal are added, weighted with factors. If the component of the spherical pattern (term K) of the general second-order directional pattern is not to be neglected, this component can be generated as a fifth received signal, for example in an implementation of the figure-of-eight microphones Mik 1 . . . Mik 5 via spherical microphones, by picking up at least one of the signals generated by the individual spherical microphones and then processing the signal. As an alternative, it is also possible to combine the first and second received signal linearly in such a manner that a fifth received signal with spherical pattern is obtained which is then added, weighted with a factor, to the sum of the first, second, third and fourth received signal. The exemplary embodiment only represents one of the embodiments possible according to the present invention. Thus, an expert active in this field is capable of creating a multiplicity of further embodiments via advantageous modifications (e.g., modifications of the method steps, modification of the placement of the microphones, use) without changing the character (nature) of the present invention (minimum number of directional microphones due to multiple use for the signal processing, generation of suitable trigonometric functions in dependence on the orientation of the main lobe for generating necessary patterns, etc). These embodiments are also to be covered by the present invention.

Provided is a directional-microphone system, as well as a method for signal processing in such a directional-microphone system, wherein a particularly controllable second-order directional-microphone pattern is ensured while the number of figure-of-eight microphones required to generate such pattern is minimized.

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention generally relates to computer systems which include a cache memory. Still more particularly, the present invention relates to a cache memory implementation in which the memory locations of the cache can be selectively flushed. 2. Description of the Relevant Art A cache memory is a high-speed memory unit interposed in the memory hierarchy of a computer system generally between a slower system memory (and/or external memory) and a processor to improve effective memory transfer rates and accordingly improve system performance. The cache memory unit is essentially hidden and appears transparent to the user, who is aware only of a larger system memory. The cache memory usually is implemented by semiconductor memory devices having access times that are comparable to the clock frequency of the processor, while the system and other external memories are implemented using less costly, lower-speed technology. The cache concept is based on the locality principle, which anticipates that the microprocessor will tend to repeatedly access the same group of memory locations. To minimize access times of this frequently used data, it is stored in the cache memory, which has much faster access times than system memory. Accordingly, the cache memory may contain, at any point in time, copies of information from both external and system memories. If the data is stored in cache memory, the microprocessor will access the data from the cache memory and not the system or external memory. Because of the cache memory's superior speed relative to external or system memory, overall computer performance may be significantly enhanced through the use of a cache memory. A cache memory typically includes a plurality of memory sections, wherein each memory section stores a block or a "line," of two or more words of data. For systems based on the particularly popular model 80486 microprocessor, for example, a line consists of four "doublewords" (wherein each doubleword comprises four 8-bit bytes). Similar configurations may be used in Pentium compatible microprocessors. Each cache line has associated with it an address tag that uniquely associates the cache line to a line of system memory. When the processor initiates a read cycle to obtain data or instructions from the system or external memory, an address tag comparison first is performed to determine whether a copy of the requested information resides in the cache memory. If present, the data is used directly from the cache. This event is referred to as a cache read "hit." If not present in the cache, a line containing the requested word is retrieved from system memory and stored in the cache memory. The requested word is simultaneously supplied to the processor. This event is referred to as a cache read "miss." In addition to using a cache memory during data retrieval, the processor may also write data directly to the cache memory instead of to the system or external memory. When the processor desires to write data to memory, an address tag comparison is made to determine whether the line into which data is to be written resides in the cache memory. If the line is present in the cache memory, the data is written directly into the line in cache. This event is referred to as a cache write "hit." A data "dirty bit" for the line is then set in an associated status bit (or bits). The dirty status bit indicates that data stored within the line is dirty (i.e., modified), and thus, before the line is deleted from the cache memory or overwritten, the modified data must be written into system or external memory. If the line into which the data is to be written does not exist in the cache memory, the line is either fetched into the cache memory from system or external memory to allow the data to be written into the cache, or the data is written directly into the system memory. This event is referred to as a cache write "miss." Complicating the use of cache memory is the fact that many personal computers include the capability of adding external memory on which relevant data can be stored permanently. Some external memory devices have the size and shape of a credit card and can be inserted into the computer system in a similar fashion to floppy diskettes. These cards are typically referred to as PCMCIA cards, and are used on a regular basis in portable computers to expand the available memory of these computers. Once inserted into an appropriate slot in the computer system, data then can be read from and written to the external memory card. Like a floppy disk, the memory card can be removed from the computer system at any time. Unique problems occur, however, when using cache memory in association with a removable external memory card. The cache memory in the computer may be used to expedite accesses to several memory sources such as system memory and external memory cards. The contents of cache memory, therefore, may reflect the contents of both system and external memory. Memory cards, however, unlike system memory, can be removed from the host device during normal operations. When an operator removes a memory card, the cache contents associated with that card become invalid and should not be accessed by the central processor unit (CPU). Of particular concern is the resulting errors from replacing one memory card with another card. In this situation, the CPU may associate the cache contents pertaining to the memory card previously removed with the new card, thus creating errors as the old card's data may be completely unrelated to the new card's data. To eliminate this potential problem, the industry has taken one of two general approaches. The first approach is to make the contents of the external memory device non-cacheable. While this approach effectively eliminates the problem, it does so at the expense of system performance by not using the cache memory for any transactions to external memory. Instead, all external memory transfers must be accomplished directly through the external memory device. A second approach is to completely flush the cache any time an external memory device is removed from the system. Thus, once the memory card is removed, the entire contents of the cache are "flushed" (i.e, invalidated). Once again, while this approach eliminates the problem, it does so at the sake of system performance by essentially resetting the cache memory. Flushing the entire cache memory contents may be inefficient and wasteful because valid contents unrelated to the removed memory card are flushed unnecessarily. An analogous situation would be the classic case of cutting off a hand because a problem exists with a thumb. Efficiency, therefore, would be enhanced if the cache memory contents could be selectively flushed to invalidate only those contents that have become invalid when, for example, a memory card has been removed. With such a cache memory implementation, valid and unaffected cache data would not be flushed and overall computer performance would be enhanced. Further, such a cache memory implementation would provide a valuable step in the implementation of a plug-n-play computer system, which requires the computer system to adapt on-the-fly as system components and peripheral devices are changed. SUMMARY OF THE INVENTION The present invention solves the shortcomings and deficiencies of the prior art by constructing a computer system capable of selectively flushing a cache memory. In the preferred embodiment, a processing unit contained in the computer system compares cache memory tag address values with the addresses assigned to an external memory device. The processing unit includes registers which provide a window of address values available in the external memory device. The registers preferably include a lower start address register and an upper end address register, which, when initiated, are loaded with the start and end values of the external memory addresses, respectively. A lower and upper comparator compares each tag address from the cache memory with the values in the lower and upper registers, respectively. If a tag address is found which has a value within the window defined by the upper and lower address registers, it is invalidated and the corresponding data is flushed from the cache memory. As an alternative to this hardware implementation of the present invention, instructions may be written in microcode to perform a similar process. Thus, the start and end address values of the external memory device would be fetched and compared through software routines with the tag address values. An instruction to flush a particular line in the cache memory then would be generated by the processor in response to an affirmative comparison. In yet another alternative embodiment, a bus interface unit is provided which contains a memory map of the available addresses in an external memory device. In response to removal of the external memory from the computer system, the bus interface unit sequentially cycles through each available external memory address in the memory map, requesting the cache controller to compare the memory address to tag addresses in cache memory. If a match for the external memory address is found in the tag address, the cache memory contents corresponding to that tag address are invalidated. BRIEF DESCRIPTION OF THE DRAWINGS Other objects and advantages of the invention will become apparent upon reading the following detailed description and upon reference to the accompanying drawings in which: FIG. 1 is a schematic block diagram of a general computer system construction, with a cache memory internal to a microprocessor; FIG. 2 is a schematic block diagram illustrating a configuration of the local bus interface unit and cache memory controller in accordance with an exemplary embodiment; FIG. 3 is flow chart illustrating the preferred process operation to initiate a partial flush of the cache memory; and FIG. 4 is a schematic block diagram depicting an alternative embodiment for initiating a partial cache flush through the use of an external bus interface unit. While the invention is susceptible to various modifications and alternative forms, specific embodiments thereof are shown by way of example in the drawings and will herein be described in detail. It should be understood, however, that the drawings and detailed description thereto are not intended to limit the invention to the particular form disclosed, but on the contrary, the intention is to cover all modifications, equivalents and alternatives falling within the spirit and scope of the present invention as defined by the appended claims. DETAILED DESCRIPTION OF THE INVENTION Turning now to the drawings, FIG. 1 is a block diagram of a general computer system 100 for which the present invention is adapted. The computer system 100, in accordance with generally known conventions, includes a microprocessor or "processor" 101 which functions as the brains of the computer system 100. Processor 101 includes a CPU core 102 coupled to a cache memory 106 by a local bus 165, a cache controller 108, and registers 129. CPU core 101, cache memory 106, cache controller 108 and registers 129 are coupled to a system bus 112 via a local bus interface 109. As one skilled in the art will understand, any of the peripheral components of the processor 101, such as cache memory 106, may be located externally from the processor 101. Similarly, other components shown as external to the processor 101 in FIG. 1 may be integrated as part of microprocessor 101. As will be understood by one skilled in the art, in such a situation the system bus 112 may form part of the CPU local bus 165. The computer system 100 also preferably includes a bus interface unit 110, a local bus peripheral device 111, and a memory controller 116, all connected to the processor 101 via system bus 112 and local bus interface 109. Alternatively, the processor 101 may include the bus interface unit 110, the peripheral device 111, and memory controller 116 as integrated components in the processor design. Bus interface unit 110 provides an interface between an external peripheral bus 120 and the system bus 112 and orchestrates the transfer of data, address and control signals between these busses. As shown in FIG. 1, an external system memory 114 also preferably couples to system bus 112 through memory controller 116. The memory control unit of FIG. 1 couples to the system bus 112 and to a memory bus 117 to control memory transactions between system components and system memory 114. The system memory 114 typically includes banks of dynamic random access memory (DRAM) circuits. The DRAM banks, according to normal convention, comprise the working memory of the integrated processor 100. The DRAM circuits connect to the memory controller 116 via a memory bus 117, comprised of memory address lines, memory data lines, and various control lines. In accordance with the exemplary embodiment of FIG. 1, the memory control unit 116 may also connect to a read only memory (ROM) device (not shown) via the memory bus 117. The ROM device may store the BIOS (basic input/output system) instructions for the computer system. As one skilled in the art will understand, the BIOS ROM may be located elsewhere in the computer system if desired. An alternate peripheral device 122, such as a DMA controller or other device, also may couple to peripheral bus 120. In its illustrated form, computer system 100 embodies a single processor, single-cache architecture. It is understood, however, that the present invention may be adapted to multi-processor and/or multi-cache systems. It is further understood that a variety of other devices may be coupled to peripheral bus 120. The peripheral bus may comprise a PCI bus, an ISA bus, an EISA bus, or any other standard bus. Peripheral device 122 may be illustrative of a variety of bus mastering devices. Exemplary alternate bus masters include disk drives, CD ROM units, and local area network (LAN) devices. The CPU core 102 preferably includes an internal ROM 127 in which the microcode for the CPU 102 is stored. The CPU core 102 is illustrative of, for example, a Pentium compatible microprocessor, with reduced instruction set computer (RISC) operations. The CPU local bus 165 is exemplary of a Pentium compatible style local bus. The CPU local bus 165 includes a set of data lines, a set of address lines, and a set of control lines (not shown individually). Thus, according to normal convention, the processor 101 couples to other peripheral computer components through one or more external buses, such as system bus 112, peripheral bus 120, and memory bus 117. Various peripheral devices 111, 122 may reside on these busses. As shown in FIG. 1, a removable card slot driver may also reside on the peripheral bus 120 or system bus 112, for receiving a removable card, such as a removable external memory device. The external memory device may comprise, for example, a memory card on which the stored information is magnetically encoded. The external memory device in slot driver 144, or peripheral device 122, may also comprise a CD ROM unit, a disk driver, or a local area network (LAN). The details of the cache memory 106 and cache controller 108 will now be discussed. Referring still to FIG. 1, each line of cache memory 106 has associated therewith address tag and state information. The address tag indicates a physical address in system memory 114 or in external memory (such as may be present for example in the removable card driver 144) corresponding to each entry within cache memory 106. In this embodiment each entry within cache memory 106 is capable of storing a line of data. A line of data consists of four doublewords (where each doubleword comprises 32 bits). It is understood, however, that a line could contain any number of words or doublewords, depending upon the system. It is further understood that a doubleword could consist of any number of bits. The state information may, for example, comprise a valid bit and a set of dirty bits. A separate dirty bit is allocated for each doubleword within each line. The valid bit indicates whether a predetermined cache line contains valid cache data, while the dirty bits identify the write status of each double word within each cache line. In an invalid state, there is no valid data in the corresponding cache memory entry. In a valid and clean state, the cache memory 106 entry contains valid data which is inconsistent with system memory 114. Typically, the dirty state results when a cache memory entry is altered by a write operation. Cache controller 108 includes an address tag and state logic circuit 130 that contains and manages the address tag and state information, and a comparator circuit 132 for determining whether a cache hit has occurred. Although not shown, the cache controller 108 may include other logical elements, including for example a snoop write-back circuit that controls the write-back of dirty data within cache memory 106. It will be appreciated by those skilled in the art that cache controller 108 may contain other additional conventional circuitry to control well-known caching functions such as various read, write, update, invalidate, copy-back, and flush operations. Such circuitry may be implemented using a variety of specific circuit configurations. Examples of such specific circuit configurations may be found in a host of publications of the known prior art. As stated previously, each line of data within cache memory 106 is associated with four doublewords of data. Address tag and state logic circuit 130 indicates a physical address in system memory 114 corresponding to each line entry within cache memory 106, and further stores a valid bit and a set of dirty bits associated with each line of data. A separate dirty bit is provided for each doubleword of data within each line. As will be better understood from the following, the address tag and state logic 130 monitors cycles executing on system bus 112 and detects the initiation of a memory cycle (i.e., read or write cycle) by any alternate bus master device in the computer system 100. It is noted that such a cycle could be initiated by peripheral device 122 or by local bus peripheral 111 (i.e., if configured as DMA controller). Referring now to FIG. 2, portions of the cache controller and local bus interface unit are shown in accordance with the preferred embodiment. One skilled in the art will understand that the portions of the bus interface unit and cache memory shown in FIG. 2 may be located in the CPU core or in other locations on or off chip. FIG. 2, therefore, is merely illustrative of the preferred implementation of the present invention. As shown in FIG. 2, the local bus interface unit 109 includes state logic 205, a lower address register 215, and an upper address register 225. The lower address register 215 and upper address register 225 receive lower and upper window address values on bus 275 for the external memory device when the external memory device is removed from the system. Bus 275 may comprise either the local bus or the system bus in the configuration of the system shown in FIG. 1. The address registers receive control signals LEADS and UEADS from the state logic 205 to initiate loading of the appropriate window address value. Those values can be obtained from appropriate registers configured in the BIU 110 (FIG. 1), for example. Similarly, the comparator circuit 132 includes a lower window comparator 220 and an upper window comparator 230, each of which couple to the lower and upper address registers 215, 225, respectively. As one skilled in the art will understand, comparators 220, 230 may be located in the local bus interface 109 or in CPU core 101, if desired. The cache address tag and state logic 130 preferably includes an address tag array 245 and a tag controller 255. The address values stored in the lower and upper address registers 215, 225 are periodically provided as input signals to the associated comparator 220, 230, respectively. The comparator 220, 230 also receives as input signals tag address values from the address tag array 245. The output generated by comparators 220, 230 are relayed to the state logic 205 as signals GTEQ (greater than or equal) from lower window comparator 220, and LTEQ (less than or equal) from upper window comparator 230. The state logic 205 receives as an input a window invalidate (WINDOW -- INVD) signal, which initiates the invalidation process. The state logic also receives a lower enable address (LEADS) signal and an upper enable address (UEADS) signal to indicate that a valid lower or upper window address is being provided on either the system bus or the local bus. In response to receipt of the WINDOW -- INVD signal and the LEADS or UEADS, the state logic 205 enables either the lower address register 215 or the upper address register 225 to capture the window address on the bus 275. The state logic 205 also receives the GTEQ signal from lower window comparator 220, and the LTEQ signal from upper window comparator 230. In response to a hit signal from both comparators, indicating that the tag address is within the external memory window address, the state logic 205 produces an invalidate (WIND -- INVD) signal and the tag address number (WINDOW -- NUMBER) to the tag controller 255, causing the tag address identified by the WINDOW -- NUMBER signal to be flushed from the cache memory. After completion of the partial flush, the state logic generates an acknowledge (WINDOW -- INVD -- ACK) signal. Referring still to FIG. 2, the address tag array 245 includes the tag addresses stored in the cache memory. The tag controller 255 controls the generation of the tag addresses, and functions in the preferred embodiment to implement any flushing of tag address values. The tag controller 255 preferably causes the address tag array 245 to sequentially transmit each of the stored tag values to the comparators 220, 230 via the local bus. The comparators 220, 230 receive the tag address values from the address and compare each tag value with the lower and upper window address of the removed external memory, which is obtained from the lower address register 215 and upper address register 225, respectively. Referring to FIGS. 1 and 2, in an alternative embodiment, the window invalidation may be implemented through instruction in the CPU microcode stored in ROM 127. In this embodiment, the lower and upper address window values are fetched in a software routine and compared with each of the address tag values fetched from the address tag array. Referring now to FIGS. 2 and 3, an exemplary process for implementing the present invention now will be described. In step 302, the local bus interface (or alternatively the CPU core) determines if a partial flush has been requested. Typically, such a partial flush will be initiated in response to detecting that an external memory device has been removed from the system, disabled or modified in some fashion. Upon detecting such a condition, the bus interface unit may issue a WINDOW -- INVD signal, followed by the lower and upper address values and upper and lower enable address signals (UEADS and LEADS) to load the lower and upper address registers 215, 225 (step 304). In step 306, the lower and upper address window values are compared in comparators 220, 230 with a tag address obtained from address tag array 245. If the tag address is greater than or equal to the lower address register value (step 308) indicated by the GTEQ signal, and less than or equal to the upper address register value (step 310) indicated by the LTEQ signal, then the state logic 205 transmits an invalidate (WIND -- INVD) signal and the address to be invalidated (WINDOW -- NUMBER) to the tag controller 255 (step 312). In step 314, the tag controller determines if all tag addresses have been compared to the window address values in registers 215, 225. If all tag address values have not been checked, the tag controller causes the next tag address to be sent to the comparators for comparison with the window values. Referring now to FIG. 4, the cache comparator circuitry 432 and the address tag and logic 430 are shown in isolation with the bus interface unit or BIU 410 interconnected by bus 465. The bus 465 may comprise either a system bus or a local bus for transmitting address values between the BIU 410 and the cache controller logic. In the exemplary embodiment shown in FIG. 4, the BIU 410 generates an address value that is transmitted on bus 465 to comparator circuitry 432 and address tag and logic 430, when a CARD GONE signal is received at BIU 410. The BIU also transmits control (EADS and WINDOW -- INVD) signals to the cache controller logic to indicate the presence of a valid address on bus 465, and to request a partial flush of the cache memory. The BIU receives a hit (HIT) signal from comparator circuitry 432. In the embodiment shown in FIG. 4, the BIU includes a lower address register 460 and an upper address register 470 to specify the memory address window of the removed external memory device. As one skilled in the art will understand, other registers and formats may be used to provide a map of the memory address window values. For example, one or more register(s) may be provided which indicates the start address of the memory values, and an offset for the memory address, which when summed with the start address provides the upper address boundary for the memory. In the embodiment shown in FIG. 4, a counter 485 receives the start address value from register 460, and then counts sequentially to provide subsequent address values. The BIU control logic 450 receives the count from counter 485, compares the count with the upper address value determined from register 470 (or from an offset value), and transmits the address value on bus 465 if the count value is within the memory address window. Substantially simultaneously with the assertion of the address signal on buss 465, the control logic 450 also generates the EADS signal to the address tag and state logic 430 to indicate a valid address is on bus 465. The address tag and state logic 430 includes an address tag array 445 and a tag controller 455. The tag controller receives the control signals from the BIU 410, and generates in response to the EADS signal a comparator enable (COMP ENABLE) signal to permit the comparator circuitry 432 to latch in the address signal appearing on bus 465, and a enable tag (ENABLE TAG) signal to cause address tag array 445 to transmit an address tag value to comparator circuitry 432. The address tag array 445 preferably transmits each tag array value in sequence in response to enable signals from the controller 455. In response to the assertion of the WINDOW -- INVD signal, the tag controller 455 flushes the particular tag address appearing on bus 465. Comparator circuitry 432 includes a comparator 425 for receiving address values from the BIU 410 and the address tag array. The comparator 425 is enabled by an appropriate control signal from tag controller 455 (or alternatively from BIU 410). If the comparator determines that the address values are equal, it generates a hit (HIT) signal that is transmitted to control logic 450. The operation of the BIU initiated flush will now be described with reference to the exemplary embodiment of FIG. 4. When an external card is removed from the computer system, or when a system component is modified or disabled, a CARD GONE or similar signal is provided to the BIU 450. The control logic 450 initializes counter 485, causing it to load the start address for the device which has been removed, disabled or modified. This start address is transmitted on bus 465, at substantially the same time that the EADS signal is asserted. The tag controller enables the comparator to load the address value, while also enabling the address tag array to begin transmitting tag address values to the comparator 425. The comparator 425 compares each of the tag address values with the address value from the BIU 410. If a match is found, the HIT signal is transmitted to the control logic 450, which in turn sends an invalidate (WINDOW -- INVD) signal to the controller to flush this particular tag address value. If no match is found for any address tag, the tag controller sends a TAG CYCLE DONE signal to the control logic to indicate that all address tags have ben compared. The control logic then increments the counter 485, and if the new value is not above the value in the upper address register 470, transmits this new address value to the comparator 425 to perform a new comparison with each address tag value. This operation continues until all address values in the removed memory device have been considered. Numerous variations and modifications will become apparent to those skilled in the art once the above disclosure is fully appreciated. It is intended that the following claims be interpreted to embrace all such variations and modifications.

A computer system is disclosed for selectively invalidating the contents of cache memory in response to the removal, modification, or disabling of system resources, such as for example, an external memory device. The computer system includes an interface unit which defines an address window for the particular system resource. The address window is implemented through the use of a lower address register and an upper address register, which are loaded in response to a lower and upper enable address signal. An upper comparator compares each tag address with the upper address register value, and a lower comparator compares each tag address with the lower address register value. If the tag address falls within the window, it is flushed by the generation of appropriate control signal. In an alternative embodiment, the present invention can be implemented through software by instructions in microcode. As yet another alternative, the present invention can be implemented by comparing each memory window address value with the stored tag address in the cache.

CROSS REFERENCE TO RELATED APPLICATION The present application is a continuation-in-part of PCT application No. PCT/IT97/00150, filed Jun. 25, 1997, which claims priority from Italian application No. RM96/A000451, filed Jun. 27, 1996, the entire contents of both of which are hereby incorporated by reference. DESCRIPTION A proposal for a suture block for surgical sutures. This carefully-devised invention is made of re-absorbable, non-re-absorbable, metallic or a blend of materials, just like normal two-part surgical sutures, which are joined together and secured to prevent the thread from coming undone. Apart form the traditional knot, the options which exist today as regards securing sutures, consist of metal clips or clips made of materials which are gradually reabsorbed. Clips, however, block the thread in the acute angle formed by the two linear parts before they are closed--in other words, in the vertex of the "V". Yet this an unsuitable and imbalanced position since the thread is subjected to traction and tension. Thus, instead of being and remaining in a perfectly orthogonal position in the direction of the traction, the clip tends to assume a vertical position, putting the tissue at one end under pressure and losing optimum surface contact--and hence much of the stability needed for it to serve its purpose. What's more, the linear form of the clip, once closed, is completely ineffectivetl in achieving the desired effect. Invented to hold vessels of tissue together, it is used incorrectly to secure threads. I should add that the use of metal clips entails the use of excessive amounts of material--something which the patent finds hard to accept and which, moreover, interferes with certain diagnostic techniques. Clips made of re-absorbable material do not grip the thread and pose the same problems in terms of stability and ergonomics. Even the recent introduction of the Lapra-Ty suture block, which addresses the problem, does not entirely solve it. In practice, this invention works on the basis of the same principle as a normal clip, already outlined, combined with an eccentric clasp and stop, which thus give rise to its shortcomings, namely, its instability and poor ergonomics. The only difference is that it is thicker than a normal clip and thus relies on this increased contact surface area, in order to secure the thread. The manufacturers themselves suggest that it only be used with woven threads, i.e. with those which nay be compressed and flattened, and which have a limited diameter in other words, least resistant ones. Another method of securing a thread is by passing it through a little bead followed by a small lead ring, which works like a cork and a lead pellet. This method which is used only for cutaneous sutures, has several drawbacks. Firstly, the surgeon is forced to thread the needle first through the bead and then through the lead pellet, which must finally be secured using a surgical instrument: secondly, there is the risk that the needle holder lose its grip, and having to chance instrument is a further waste of time. Besides, the threads available on the market are meant for continuous sutures and a similar procedure for sutures consisting of isolated stitches would be unthinkable, due to the sheer number of beads and lead pellets required, and the risk of confusion on the operating table, which could easily result. Lastly, the sphere which functions as a suture block and which is positioned between the tissue and the lead pellet, in theory only has punctiform contact with the tissue, when fill surface contact is what is really required. In fact, contact between the sphere and the tissue plane only occurs at the tangential point. The result here too is therefore also usatisfactory: in practice, the larger the contact surface area, the less is the pressure when equal force is applied, and, subsequently, the minor the damage done by the suture block to the tissue. The fact that none of these methods are used as a matter of course as a way to avoid tying knots, proves the point. In laparoscopic surgery the same problem exists--all the methods used to secure a suture are awkward and imprecise. Too many problems and risks are therefore involved, using clips for a different purpose from which they were intended, makes the surgeon feel uneasy, and the use of beads and lead pellets, is too complicated, empiric and haphazard. The innovations introduced with this invention are aimed at offering the surgeon with a new, quicker suture technique, which is less painfull and less traumatising for the tissue, and, on occasions, easier to perform. The first characteristic of the invention is its disc-shaped form which provides the optimal surface area for contact with the tissue, whilst using the minimum of material. It thereby distributes the tension of the thread uniformly over the largest possible surface area. The second characteristic of the invention is that it enables the thread to be passed through the centre of the disc thus saving time and, should there be traction, provides balance and stability, guaranteeing optimal, uniform contact between the surface of the disc and the tissue. Another characteristic of the invention is its suture blocking system which prevents the thread from working itself loose and at the same time does not weaken it, which is fundamental given the tension to which it is regularly subjected. Another characteristic of the invention is that it has a peg--the "male" part--which thanks to a labyrinthine system, gradually blocks the thread whatever its thickness (within, of course, the limits of the calibres and materials normally used in surgery). Another characteristic of the invention is that it exploites the elasticity and plasticity of the materials normally used in surgery in order to obtain a suture block fashioned in such a way that as the peg gradually enters its female counterpart, the walls "give" because of their elastomeric properties, both in order to hold the thread in place and to adapt to its variable diameter, without compressing it to such an extent that its resistance is reduced. Another characteristics of the invention is that the front face of the male peg has what could be described as a "V"- shaped mouth, which serves both to position the thread within the suture block, and to ensure that as the thread is introduced, it is gradually tightened, irrespective of its thickness, by a self-blocking system which is independent from the above-mentioned labyrinthine mechanism The self-blocking system is the result of the combined effect of the "V"-shaped mouth, and the light pressure to which the two jaws of the "V" are subjected as the suture stop is closed. It works in the same way as the sheet pins on a yacht. Another characteristic of the invention is that the male part is locked into the shell by a press-stud, spring toggle, or a mixed system Another characteristic of the invention is that its shell may consist of two separate pieces, or may be a single system in which the parts are hinged together, or attached to each other by a film. Another characteristic of the invention is that it has been designed in such a way as to ensure that the thread is always clamped at the centre of the system. Another characteristic of the invention is that a suture which is bound to the tissue is obtained, without the latter being constricted by a knot. This lowers the risk of eschew reduces pain and limits tissue trauma and damage. Another characteristic of the invention is that the edges are rounded and so they reduce the damage that could be caused should they come into contact with the tissue. Another characteristic of the invention is the ease, simplicity and speed with which it may be applied, reducing the complexity, length and cost of the surgical operation. Another characteristic of the invention is that once the disc has been secured at the end of a continuous or isolated--stitch suture by applying a second disc close to the previous one and then cutting the thread between the two, the suture can be made ready for the next stitch, with the suture block already in place at the end of the disc. Another characteristic of the invention is that its saves on the large quantities of sutural thread normally required. Another characteristic of the invention is that it can be applied independently, or with disposable loaders, as is the case with clips. Another characteristic of the invention is to offer the surgeon the possibility of performing a suture involving several stitches, without having to change the disposition of the operational field and without having to put down his instruments to free his hands to tie the knots. With reference to the Figures, the number 1 indicates a suture block for surgical sutures made of re-absorbable or non re-absorbable material. Specifically, the suture block 1 comprises a body 2 of essentially discoidal shape wherein it presents a through female cavity 4 obtained in at least one part 3a, 3b. The number 5 indicates a male peg which is destined to be stably coupled by forced insertion into the female cavity 4 through forced fastening means. Advantageously the peg 5 presents a Transverse through slot 12 which runs longitudinally to the length of the peg 5) to lighten and increase its elastic characteristics. The discoidal body 2 presents centrally an opening 6 for the passage and the transverse positioning into said female cavity 4 of a suture thread. The opening 6 is destined to co-operate with a V-shaped opening 7, elastically deformable, presented by the front end of the male peg 5 centring and blocking the suture thread, whatever its thickness, through the forced insertion of the male peg 5 into said female cavity 4. As is seen in the drawing, the opening 6 may have the shape of a slot, the length and breadth of which are transverse to the insertion direction of the peg 5. As shown in FIGS. 1 and 5, the forced blocking means are constituted by at least one tooth 8 presented laterally by the male peg 5 snapping, at the end of the forced insertion, against at least one corresponding projection 9 presented by the inner surface of the female cavity 4. As shown in particular in FIGS. 1, 2, 3, 4, the female cavity 4 passes through the entire discoidal body 2. The opening 6 for the passage and the positioning of the suture thread is obtained orthogonally to said female cavity 4, from the periphery to the centre of the discoidal body 2. Also in the Figures it is shown that the male peg 5 is inserted from the outside of the discoidal body 2 by forced insertion into said female cavity 4 and it presents on both its sides multiple teeth 8 which are destined to snap against opposing projections 9 presented by the inner surface of the female cavity 4. As shown in FIGS. 5, 6, 7 the discoidal body 2 comprises two semi-discoidal parts mutually connected at an end by a hinge element 11, wherein one of said semi-discoidal parts 3b presents integrally in correspondence with its inner surface the male peg 5 which is destined to be inserted by forced insertion into the female cavity 4 is obtained centrally in the other semi-discoidal part 3a by partial convergent rotation of said semi-discoidal parts 3a, 3b. The opening 6 for the passage and positioning of the suture thread is obtained from opposite conforming central concavities obtained on the opposing inner surfaces of said two semi-discoidal parts 3a, 3b. Advantageously as shown in all figures the discoidal body 2 presents rounded peripheral edges. Naturally, the present invention can be subject to numerous modifications and variations, without thereby departing from the inventive concept which characterises it.

A suture block is a device used to secure surgical sutures, without using knots. By securing the thread with a suture block, it is possible to close a suture in a contact with the tissue, without damaging or mortifying the latter, and without provoking icchemia in the tissue which is compressed by the loop of thread needed to tie a traditional surgical knot. This means that the surgeon no longer has to change the disposition of the operational field at each knot and can avoid having to put down the forceps or the needle-holder, in order to tie a normal knot, thereby saving time. Moreover, far less thread is required and most importantly, the pain caused by the knotted thread damaged and constricts the tissue, is significantly reduced.

CROSS-REFERENCE TO RELATED APPLICATION This application is related to, and claims the benefit of, a foreign priority application filed in China as Serial No. 200720121063.8 on Jun. 22, 2007. The related application is incorporated herein by reference. FIELD OF THE INVENTION The present invention relates to a backlight module that has a fixing structure and a liquid crystal display (LCD) device implementing the backlight module. BACKGROUND LCD devices are commonly used as displays for compact electronic apparatuses, because they provide good quality images with little power consumption and are very thin. The liquid crystal material in an LCD device does not emit light. The liquid crystal material must be lit by a light source to clearly and sharply display text and images. Thus, a backlight module is generally needed for an LCD device. Referring to FIG. 13 , a typical LCD device 1 includes a display panel 19 and a backlight module 10 opposite to the display panel 19 . The backlight module 10 is a direct type backlight module, and includes a metal back frame 15 , a plurality of light sources 14 , a diffuser 11 , and a brightness enhancement film (BEF) 12 . The plurality of light sources 14 , the diffuser 11 , and the BEF 12 are accommodated in the metal back frame 15 in that order from bottom to top. Each light source 14 is a light bar, which includes a base 141 and a plurality of light emitting elements 142 disposed on the base 141 . Some circuits (not shown) disposed on the base 141 are used for electrically connecting an external power supply (not shown) to the light emitting elements 142 . The external power supply provides power to the light emitting elements 142 , enabling the light emitting elements 142 to emit light beams. The light beams emitted from the light emitting elements 142 are provided to the display panel 19 via the diffuser 11 and the BEF 12 . The metal back frame 15 includes a bottom plate 151 and side walls 150 extending perpendicularly from the edges of the bottom plate 151 . The bottom plate 151 and the side walls 150 define an accommodating space (not labeled). The plurality of light sources 14 , the diffuser 11 , and the BEF 12 are received in the accommodating space. When the backlight module 10 is assembled, the light sources 14 are placed on the bottom plate 151 of the back frame 15 and arranged in an array. Two ends (not labeled) of each light source 14 are affixed to the bottom plate 151 using screws (not labeled). An additional screw (not labeled) can be used to fasten the middle part (not labeled) of the light source 14 to the bottom plate 151 . Thus, the backlight module 10 needs plural screws to affix the light sources 14 to the bottom plate 151 of the back frame 15 . The larger the size of the backlight module 10 , the more screws that will be needed. Screws make assembling and disassembling the light sources 14 unduly inconvenient and inefficient. Furthermore, the base 141 of the light source 14 needs to be thin for better thermal conductivity. But the base 141 is liable to warp and lose contact with the bottom plate 151 if it is too thin. Thus conduction of heat away from the light source 14 decreases when the base 141 becomes thinner. Therefore, an improved backlight module is desired to overcome the above-described deficiencies. SUMMARY An aspect of the invention relates to a backlight module including a back frame including a bottom plate and a plurality of light sources each including a base. The bottom plate includes a plurality of fixing structures that are configured for fixing the light sources to the bottom plate such that the bases of the light sources contact the bottom plate. Other novel features and advantages will become more apparent from the following detailed description and when taken in conjunction with the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS The components in the drawings are not necessarily drawn to scale, the emphasis instead being placed upon clearly illustrating the principles of at least one embodiment of the present invention. In the drawings, like reference numerals designate corresponding parts throughout the various views. FIG. 1 is an exploded, isometric view of an LCD device according to a first embodiment of the present invention. FIG. 2 is an enlarged view of a circled portion II of FIG. 1 . FIG. 3 is an exploded, isometric view of a backlight module of an LCD device according to a second embodiment of the present invention. FIG. 4 is an enlarged view of a circled portion IV of FIG. 3 . FIG. 5 is an exploded, isometric view of a backlight module of an LCD device according to a third embodiment of the present invention. FIG. 6 is an exploded, isometric view of a backlight module of an LCD device according to a fourth embodiment of the present invention. FIG. 7 is an enlarged view of a circled portion VII of FIG. 6 . FIG. 8 is an exploded, isometric view of a backlight module of an LCD device according to a fifth embodiment of the present invention. FIG. 9 is an enlarged view of a circled portion IX of FIG. 8 . FIG. 10 is an exploded, isometric view of a backlight module of an LCD device according to a sixth embodiment of the present invention. FIG. 11 is an inverted view of the backlight module of FIG. 10 when assembled. FIG. 12 is an enlarged view of a circled portion XII of FIG. 11 . FIG. 13 is an exploded, isometric view of a conventional LCD device. DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS Reference will now be made to the drawings to describe preferred embodiments of the present invention in detail. Referring to FIG. 1 , an LCD device 2 according to a first embodiment of the present invention is shown. The LCD device 2 includes a display panel 29 and a backlight module 20 opposite to the display panel 29 . The backlight module 20 is a direct type backlight module, and includes a metal back frame 25 , a plurality of light sources 24 , a diffuser 21 , and a BEF 22 . The plurality of light sources 24 , the diffuser 21 , and the BEF 22 are accommodated in the metal back frame 25 in that order from bottom to top. Each light source 24 is a light bar, and includes a base 241 and a plurality of light emitting elements 242 disposed on the base 241 . Some circuits (not shown) disposed on the base 241 are used for electrically connecting an external power (not shown) to the light emitting elements 242 . The external power supply provides power to the light emitting elements 242 , enabling the light emitting elements 242 to emit light beams. The metal back frame 25 includes a bottom plate 251 and side walls 250 extending perpendicularly from the edges of the bottom plate 251 . The bottom plate 251 and the side walls 250 define an accommodating space (not labeled). The plurality of light sources 24 , the diffuser 21 , and the BEF 22 are received in the accommodating space. A plurality of protuberant strips 252 is arranged on the bottom plate 251 in an array. Each protuberant strip 252 has the same shape as the base 241 of the light source 24 and matches to a corresponding light source 24 . An upper surface of each protuberant strip 252 is a bandy surface. Referring also to FIG. 2 , two fixture portions 254 are disposed on the bottom plate 251 and at two ends (not labeled) of each protuberant strip 252 . Each fixture portion 254 includes a groove (not labeled) for receiving the corresponding end of the base 241 . The distance between the two fixture portions 254 is slightly less than the length of the base 241 of the light source 24 , causing the base 241 to bow slightly and match with the corresponding protuberant strip 252 when the two ends of the base 241 of each light source 24 are inserted into the grooves of the corresponding fixture portions 254 . Then the light source 24 becomes fixed on the bottom plate 251 of the metal back frame 25 . The light source 24 can be detached from the bottom plate 251 by removing the ends of the base 241 from the grooves of the corresponding fixture portions 254 . In summary, the light sources 24 are fixed on the bottom plate 251 of the metal back frame 25 with the bases 241 held in contact with the bandy surfaces of the protuberant strips 252 by inserting the ends of the bases 241 into the grooves of the fixture portions 254 . Assembling the light sources 24 does not require external fasteners such as screws, making assembling and disassembling the light sources 24 convenient and efficient. Furthermore, the base 241 is forced into contact with the bandy cambered surface of the corresponding protuberant strip 252 , increasing thermal conductivity and making it difficult for the base 241 to warp. In an alternative embodiment, the plurality of light sources 24 disposed on the bottom plate 251 is not limited to an array having two columns according to the above-described embodiment. For example, the number of the columns of the array can vary according to needs. Furthermore, a screw (not labeled) can be added to affix the middle part of each light source 24 for added security. Referring now to FIG. 3 and FIG. 4 , aspects of a backlight module 30 according to a second embodiment of the present invention are shown. Two first openings 343 are disposed near an end (not labeled) of a base 341 of each light source 34 at two opposite longer edges (not labeled) of the base 341 . The two first openings 343 each have the shape of a circular arc. A second opening 344 with a rectangular (e.g., square) shape is disposed near an opposite end (not labeled) of the base 341 . A metal back frame 35 includes a bottom plate 351 and two opposite side flanges (not labeled). For each light source 34 , two first fixture blocks 353 corresponding to the two first openings 343 are disposed on the bottom plate 351 . A second fixture block 354 corresponding to the second opening 344 is also disposed on the bottom plate 351 . The second fixture block 354 has a substantially L-shaped cross-section, and can be formed by punching the bottom plate 351 . The second fixture block 354 includes a supporting portion (not labeled) and a buckling portion (not labeled). The supporting portion is connected to the bottom plate 351 , and an extending direction of the buckling portion is in a direction away from the first fixture blocks 353 . In the illustrated embodiment, an angle between the supporting portion and the buckling portion is less than 90°. The backlight module 30 is assembled by attaching the light sources 34 one by one. Each light source 34 is maneuvered so that the corresponding second fixture block 354 is received through the second opening 344 . Then the base 341 slid toward the first fixture blocks 353 and is affixed to the bottom plate 351 by buckling the neck between the first openings 343 and the first fixture blocks 353 . Thus the base 341 fully abuts the bottom plate 351 and can contact the bottom plate 351 along a length thereof. Referring to FIG. 5 this shows a backlight module 40 according to a third embodiment of the present invention. The backlight module 40 is similar to the backlight module 30 in FIG. 3 . However, two openings 443 are disposed near opposite ends (not labeled) of a base 441 of each light source 44 at two opposite longer edges (not labeled) of the base 441 . Two fixture blocks 453 corresponding to the two openings 443 are disposed on a bottom plate 451 of a metal back frame 45 . The fixture blocks 453 each have a substantially L-shaped cross-section, and can be formed by punching the bottom plate 451 . The two fixture blocks 453 each include a supporting portion (not labeled) and a buckling portion (not labeled). The supporting portions are connected to the bottom plate 451 , and extending directions of the buckling portions are in opposite directions. In the illustrated embodiment, the angle between the supporting portion and the buckling portion of each fixture block 453 is less than 90°. The backlight module 40 is assembled by attaching the light sources 44 one by one. The base 441 of each light source 44 is placed on the bottom plate 451 with the two openings 443 facing the two corresponding fixture blocks 453 . Next, the base 441 is rotated until the ends of the base 441 at the openings 443 buckle to the fixture blocks 453 of the bottom plate 451 . Referring to FIG. 6 and FIG. 7 aspects of a backlight module 50 according to a fourth embodiment of the present invention are shown. The backlight module 50 is similar to the backlight module 40 in FIG. 5 . However, two openings 543 are disposed near two ends (not labeled) of a base 541 of each light source 54 . The two openings 543 each have a rectangular (e.g., square) shape. Two fixture blocks 553 corresponding to the two openings 543 are disposed on a bottom plate 551 of a metal back frame 55 . The fixture blocks 553 can be formed by punching the bottom plate 551 and creating angles with the bottom plate 551 . The extending directions of the two fixture blocks 553 are toward each other. In the illustrated embodiment, the fixture blocks 553 are gently curved or arced. The angle between each fixture block 553 and the bottom plate 551 is less than 90°. The backlight module 50 is assembled by attaching the light sources 54 one by one. The base 541 of each light source 54 is slightly bent until the corresponding fixture blocks 553 of the bottom plate 551 are inserted into the openings 543 and buckle the base 541 at the openings 543 when the base 541 rebounds. Thus the base 541 abuts the bottom plate 551 , and the light source 54 is fixed to the bottom plate 551 . Referring to FIG. 8 and FIG. 9 , aspects of a backlight module 60 according to a fifth embodiment of the present invention are shown. The backlight module 60 is similar to the backlight module 50 in FIG. 6 . However, fixture blocks 653 are disposed on a bottom plate 651 of a metal back frame 65 . Each fixture block 653 includes a supporting portion 654 , a connection portion 655 , and a buckling portion 656 that are connected. The supporting portion 654 is connected to the bottom plate 651 . The buckling portion 656 includes a downwardly curved part (not labeled). Typically, the buckling portion 656 is resiliently deformable. The fixture blocks 653 are arranged in pairs, with the fixture blocks 653 in each pair pointing in the same direction. The two fixture blocks 653 correspond to two openings 643 of a base 641 of a respective light source 64 . The backlight module 60 is assembled by attaching the light sources 64 one by one. Each pair of fixture blocks 653 are inserted into the two openings 643 of the base 641 of the corresponding light source 64 . Then the base 641 is moved along the opposite direction to the pointing direction of the fixture blocks 653 until the buckling portions 656 press against the base 641 . Thus, the base 641 abuts the bottom plate 651 , and the light source 64 is fixed to the bottom plate 651 . Referring to FIGS. 10-12 , aspects of a backlight module 70 according to a sixth embodiment of the present invention are shown. The backlight module 70 is similar to the backlight module 20 in FIG. 1 . However, a bottom plate 751 of a metal back frame 75 of the backlight module 70 includes a plurality of recesses 752 . The recesses 752 are stripe shaped and can be formed by punching the bottom plate 751 . The number of the recesses 752 matches the number of light sources 74 and the size and shape of each recess 752 match the corresponding light source 74 . Each recess 752 includes four side walls (not labeled). Two through holes (not labeled) are disposed on the two side walls at opposite ends (not labeled) of the recess 752 . A fixture block 753 is disposed at the center part of one of the two longer opposite side walls of the recess 752 . An opening 743 corresponding to the fixture block 753 is disposed on a base 741 of the corresponding light source 74 . The base 741 is longer than the recess 752 . The backlight module 70 is assembled by attaching the light sources 74 one by one. The base 741 of each light source 74 is slightly bent until the two ends of the base 741 are inserted into the two through holes disposed on the two side walls at the two opposite ends (not labeled) of the recess 752 . Then the base 741 rebounds and abuts the bottom plate 751 , with the fixture block 753 fitting into the opening 743 thereby fixing the base 741 on the bottom plate 751 . It is to be understood that even though numerous characteristics and advantages of the present embodiments have been set forth in the foregoing description with details of the structures and functions of the embodiments, the disclosure is illustrative only, and changes made in detail, especially in matters of shape, size, and arrangement of parts, within the principles of the invention, to the full extent indicated by the broad general meaning of the terms in which appended claims are expressed.

An exemplary backlight module ( 20 ) includes a back frame ( 25 ) including a bottom plate ( 251 ) and light sources ( 24 ) each including a base ( 241 ). The bottom plate includes fixing structures ( 254 ) that are configured for fixing the light sources to the bottom plate such that the bases of the light sources contact the bottom plate. A liquid crystal display device ( 2 ) using the backlight module is also provided.

RELATED APPLICATIONS The present application is a continuation of application Ser. No. 09/867,718, filed May 29, 2001, now abandoned, claims priority under 35 U.S.C. § 119(e) from provisional application Ser. No. 60/207,540, filed May 26, 2000. TECHNICAL FIELD The present invention is directed generally to a method and apparatus for generating high-power coherent light; and more particularly to a method and apparatus for generating high-power coherent light from arrays of vertical cavity surface emitting lasers (VCSELs). BACKGROUND ART VCSEL arrays can be used as low-cost, high-power light sources for a variety of military and commercial applications. Currently, the cost of high power (500 to 1000 W) Nd:YAG and CO 2 lasers exceed $100/Watt. Coherent VCSEL arrays have been realized in the premises network market where low power (<0.005 W), VCSEL based transceivers selling for ˜$100 dominate the market, having displaced edge-emitting semiconductor laser based transceivers that sell in the $500 to $5000 range. Other applications, such as optical pumps at 980 nm for Erbium-doped fiber amplifiers (EDFAs) for telecommunications will benefit from low cost lasers with increased power (0.05 to 1.0 W). High-powered EDFAs cannot be achieved from single element VCSELs, but could be economically fabricated with VCSEL arrays. VCSEL arrays are theoretically capable of kW of power with current material and heat sinking technology. Aside from these commercial and economic applications, coherent arrays of VCSELs have far-reaching significance because they have the potential to deliver >>1 W of power, over a wide variety of wavelengths. These devices can be used to accelerate progress in areas such as medicine, communications, manufacturing, and national defense. High-power VCSEL arrays have been demonstrated by several research groups. Grabherr et al. reported VCSEL power densities exceeding 300 W/cm 2 from a 23-element array [M. Grabherr et. al., Electron. Lett., vol. 34, p. 1227, 1998]. Francis et al. demonstrated VCSEL power in excess of 2-W continuous wave and 5 W pulsed from a 1000-element VCSEL array [D. Francis, et. al., IEEE Int. Semiconductor Laser Conf. (ISLC), Nara, Japan, October 1998]. Chen et al. also reported the power density of 10 kW/cm 2 from an array of 1600 VCSELs using a microlens array to individually collimate light from each laser [H. Chen, et. al., IEEE Photon. Technol. Lett., vol. 11, No. 5, p. 506, May 1999]. However, their beam quality at high power is still poor. A high quality beam requires a narrow linewidth single mode with high spatial and temporal coherence. In order to produce coherent, single-frequency, high-power arrays of VCSELs, the elements of one or two-dimensional VCSEL arrays should be phase-locked. Although the light from each individual VCSEL is coherent, the phase and frequencies (or wavelengths) of the light from each VCSEL are slightly different, and therefore uncorrelated. For such an incoherent array consisting of N elements producing the same power P, the on-axis power in the far-field is ˜NP. However, if the array can be made coherent, in phase, and with a single frequency, the on-axis power in the far-field is N 2 P and the width of the radiation pattern is reduced by ˜1/N. This high on-axis far-field power is required in laser applications such as free space optical communications and laser radar where a large amount of power is required at a distance, or in applications such as laser welding, laser machining, and optical fiber coupling that require high power to be focused to a small spot. Previous efforts to phase-lock arrays of VCSELs have used diffraction coupling [J. R. Legar, et. al., Appl. Phys. Lett., vol. 52, p. 1771, 1988] and evanescent coupling [H. J. Yoo, et. al., Appl. Phys. Lett., vol. 56, p. 1198, 1990]. Diffraction coupling depends on geometrical scattering of light and evanescent coupling requires that the optical field of adjacent array elements overlap. Both approaches impose restrictions on the array architecture. More importantly, these existing approaches have had very limited success, even in 1D edge-emitting arrays where both approaches have been extensively investigated. Recently, Choquette et al. has demonstrated phase locking in a VCSEL array using an anti-guide approach [D. K. Serkland, et. al., IEEE LEOS Summer Topical Meeting, p. 267, 1999]. BRIEF SUMMARY OF THE INVENTION The foregoing and other problems and disadvantages of previous attempts to provide a high-power coherent source of light are overcome by the present invention of a high-power coherent array of vertical cavity surface emitting lasers. In accordance with the present invention, a plurality of Vertical Cavity Surface Emitting Lasers (VCSELs) are provided; along with a structure which optically couples each of the VCSELs the plurality of VCSELs to one another by a predetermined amount to cause a coherent mode locking condition to occur. The coupling structure can be a beam cube. More particularly, the beam cube is positioned to couple light from a reference source of light into the plurality of VCSELs with a vertically dependent phase, and to provide a predetermined amount of coupling between the plurality of VCSELs to cause a coherent mode locking condition to occur. Preferably, the light from the reference source which is coupled by the beam cube to the plurality of VCSELs has a phase difference between ones of the plurality of VCSELs which is substantially equal to an integer multiple of 2π radians. In one embodiment of the present invention, VCSEL/waveguide grating system for realizing high-power coherent arrays of VCSELs is provided to achieve phase locking through a waveguide with grating couplers. Coupling into and out of a waveguide using a grating is a simple method to transfer free space data to waveguides in optoelectronic integrated circuits (OEICs). Waveguide gratings can perform a large variety of functions such as reflection, filtering, deflection, and input/output coupling. A periodically modulated grating can perform holographic-wavefront conversion. As a coupler, the grating converts a waveguide mode into a radiation mode, or vice versa. Surface-normal grating couplers direct light perpendicularly into and out of the waveguide. With the advance in VCSEL technology, the use of such diffraction grating becomes an interesting mechanism to create high-power coherent light sources. The approach of the waveguide/grating embodiment of the present invention to achieve high-power coherent lasers is based on the use of a periodic grating in a common connecting waveguide to provide optical coupling between the array elements. FIG. 1( c ) shows a simplified VCSEL/waveguide structure. Each element of the array is a small optical oscillator (laser) which is defined by a pair of distributed Bragg reflector (DBR) mirrors. Each pair of DBR mirrors provides feedback to a multiple quantum well gain region, causing oscillation. Electrons and holes in the gain region produce light when current is injected into the device. Unlike previous phase locking approaches, the distribution waveguide method of the present invention can provide phase locking by controlling a precise amount of coupling between array elements independent of the element size and element spacing. A bulk beam cube, a collection of smaller distributed beam cubes, or gratings formed along the optical path, or the like, provide waveguides which collect and distribute light from/to the VCSELs, and through controlled coupling, provide a phase locking of the VCSELs. In the coupled waveguide approach of the present invention, there is provided a linear array of elements which can be extended into a 2D array. Another major advantage of this approach is that phase adjusters can be included to assist in beam-forming and electronic beam steering. In the simplest implementation, the phase adjusters could be a VCSEL element operated below lasing threshold, where variations in current correspond to refractive index changes in the gain regions causing a change in the effective optical length of the element. This approach brings the proven technological and economic benefits demonstrated by combining transistors, capacitors, and resistors into large scale integrated circuits to integrated photonic circuits consisting of lasers, optical waveguides, and grating or other couplers. These and other features and advantages of the present invention will be more readily understood upon consideration of the following detailed description of various embodiments of the present invention, and accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS FIGS. 1( a ), 1 ( b ), 1 ( c ) and 1 ( d ) are simplified illustrations of a VCSEL array and waveguide structures where light from each VCSEL is coupled into the waveguide, in accordance with the present invention. FIG. 2 is a schematic drawing of a hybrid VCSEL/waveguide structure which includes a VCSEL array and a single common waveguide with a periodic grating, in accordance with the present invention. FIG. 3 is a schematic illustration of a monolithic VCSEL/waveguide structure with a top waveguide grating coupler, in accordance with the present invention. FIG. 4 is a simplified schematic of a monolithic VCSEL/waveguide structure with an internal grating coupler, in accordance with the present invention. FIG. 5 is a transmission electron microscope (TEM) image showing the smoothing effects of a GaAs/AlGaAs superlattice growth using MOCVD. FIG. 6 presents a schematic of the waveguide grating coupler embedded in the waveguide core layer; K 0 , K d , are the wave vectors of an incoming free space beam, and diffracted wave, and the K g is a grating vector. FIG. 7 shows a typical three-layer waveguide. FIGS. 8( a ) and 8 ( b ) show a refractive index profile of an asymmetric waveguide structure which consists of four layers, and the refractive index values used for the four layers, in accordance with the present invention. FIGS. 9( a ) to 9 ( g ) show the optical confinement factor of the four-layer waveguide which is shown in FIG. 8( a ) for different cladding layer thickness d 2 (layer 2 ) of 1.5 μm and 2.0 μm, in accordance with the present invention, where FIG. 9( g ) is a Table of the refractive index values used for FIGS. 9( a ) to 9 ( f ). FIGS. 10( a ) to 10 ( d ) show the effective refractive index of the asymmetric waveguide which is shown in FIG. 8( a ) as a function of layer 3 , in accordance with the present invention. FIG. 11 illustrates the refractive index profile of a five-layer asymmetric waveguide, in which Al compositions are fixed to 0.4 and 0.15 for layers 2 and 3 , respectively, in accordance with the present invention. FIG. 12 is a plot of the grating confinement factor as a function of the thickness of the grating layer for an Al mole fraction of 0.15 in layer 3 and 0.4 in layer 2 , in accordance with the present invention. FIG. 13 exhibits the calculated results of the optimized asymmetric waveguide structure for singlemode operation at 0.85 μm, for Al mole fractions of layers 2 and 3 of 0.4 and 0.15, respectively, in accordance with the present invention. FIGS. 14( a ) and 14 ( b ) provide a plot of the real part of the effective refractive index, FIG. 14( a ), and the grating period, FIG. 14( b ), of the optimized waveguide versus the grating depth, in accordance with the present invention. FIG. 15 shows the number of TE modes in the asymmetric waveguide versus d 3 for respective Al mole fractions of 0.4 and 0.15 for layers 2 and 3 , in accordance with the present invention. FIG. 16 illustrates the calculated results for a multimode asymmetric waveguide grating coupler for different total thickness of layer 3 : 6 μm, 8 μm, and 10 μm, in accordance with the present invention. FIGS. 17( a ) and 17 ( b ) show the real part of the effective index as a function of the grating depth, and the grating period plotted versus the grating depth for different total thicknesses, respectively. FIG. 18 is as simplified illustration of an asymmetric waveguide structure with gratings, in accordance with the present invention. FIG. 19 illustrates the refractive index profile of the asymmetric waveguide shown in FIG. 18 , in accordance with the present invention. FIG. 20 provides circuit model which can be used to analyze the waveguide section of FIG. 18 , in accordance with the present invention. FIGS. 21( a ) to 21 ( d ) illustrate the scattered powers of the grating region of FIG. 18 , in accordance with the present invention. FIG. 22 illustrates the use of a four port network model to characterize the grating region, in accordance with the present invention. DETAILED DESCRIPTION OF THE INVENTION In accordance with the present invention, FIG. 1( a ) illustrates a high power coherent source 10 in which a collimated reference beam 12 is passed through a beam cube 14 and illuminates an array of VCSELs 16 . The beam cube 14 is designed so that the optical power coupled into each element of the VCSEL array 16 is sufficiently large such that the VCSELs will be coherently locked to the reference source 12 . A vertically dependent phase is introduced to the reference beam 12 as it is passed through the beam cube 14 . In order for all the VCSEL elements in the array to have the same phase and add up coherently to form a high power source, the phase difference of the reference beam between any two elements in the array should be close to a multiple of 2π radians. In order to achieve this phase front for the reference beam 12 , the beam cube 14 can be rotated. The coherently summed optical outputs 18 from the VCSEL array 16 are reflected away from the reference source by the beam cube 14 . In another embodiment of the present invention, shown in FIG. 1( b ), the bulk beam cube 14 can be replaced by many smaller beam cubes 20 , where a small beam cube 20 is associated with each element in the VCSEL array 16 . While the embodiments of FIGS. 1( a ) and 1 ( b ) are described in terms of phase adjustments, the time domain phase adjustment function of the beam cubes can instead be implemented in the frequency domain. A frequency domain implementation of phase adjustment can be realized by taking the Fourier Transform of the beam cubes 20 . In the time domain, the beam cubes 20 create phase differences across the reference beam 12 by introducing optical path length differences, which can be adjusted by rotating the beam cubes. In the frequency domain, this is equivalent to a sinusoidal where the phase relationships are adjusted by changing the period of the sinusoidal. An implementation of the above sinusoidal in the frequency domain can be accomplished by the use of surface gratings 22 on waveguides 24 , as shown in FIG. 1( c ). These surface gratings 22 can be fabricated by etching or implantation, for example. Therefore, in accordance with the present invention, a periodic grating is used to implement frequency domain phase adjustment for coherent coupling and mode locking in a VCSEL array. One difference to be noted between the embodiments of FIGS. 1( a ) and 1 ( b ) is that the reference beam 12 which was used to coherently mode lock the VCSELs in those embodiments, is replaced by coherent coupling and mode locking between the VCSEL elements in the array. This is accomplished by coupling part of a VCSEL's output power to a waveguide by the grating structure 22 and coupling part of that power to other VCSELs in the array 16 , thereby forcing all the VCSELs in the array to become mutually coherent. This enables the all the VCSEL outputs to be coherently summed for the purpose of obtaining a high power source. In this implementation, the coherent output of the VCSEL array 16 will be in the same direction as the VCSEL outputs and the waveguide 24 with the surface grating 22 is fabricated on a substrate 26 which is different from the substrate 28 on which the VCSELs are fabricated. Collimating optics 30 may be included in this implementation to improve coupling to the waveguides 24 by the surface gratings 22 . FIG. 1( d ) illustrates an alternative implementation of the embodiment of FIG. 1( c ), which involves placing a highly reflective mirror 32 on the waveguide substrate 26 to reflect light transmitted through the waveguide grating 22 back through the waveguide grating 22 . This implementation will allow the high power coherent output of the VCSEL array to be coupled to the waveguide, resulting in a high power coherent source in a normal to that of the apparatus in FIG. 1( c ). The embodiment of FIG. 1( c ) can be fabricated in a monolithic structure on a single substrate, so that the VCSEL array 16 , waveguides 24 , and gratings 22 are all formed on one substrate, for example, as shown in FIGS. 3 and 4 . This implementation doesn't require any collimating optics 30 and may or may not include mirror 32 as in FIG. 1( d ) to create a structure with the high power coherent output in the plane of the substrate. A variation to be noted between the monolithic embodiments of FIGS. 3 and 4 is that in FIG. 4 , the waveguides 24 and gratings 22 are placed within one of the VCSELs' mirrors (DBRs). The thickness of the waveguide layer 24 is such that it functions as a high index layer of the DBR. The surface-normal waveguide grating coupler embodiment of the present invention, FIGS. 1( d ), 2 , 3 , and 4 , will now be described in greater detail. A surface-normal waveguide grating coupler has been developed to achieve coherent high-power light sources. Three approaches will be described to integrate the grating-coupled waveguide with the VCSEL array: (1) a hybrid VCSEL/waveguide structure, (2) a monolithic VCSEL/waveguide structure with a top waveguide grating coupler, and (3) a monolithic VCSEL/waveguide structure with an internal waveguide grating coupler. Any architecture that attempts to combine individual semiconductor lasers into a coherent array must address several issues: 1) The coupling must achieve coherence. 2) The phase of the coupling between elements needs to be stabilized. 3) The phases should add constructively (“in phase”) for maximum on-axis power. 4) The emitting surface needs to be flat within a fraction of a wavelength. The phase of the coupling is determined by 1) the DBR mirrors; 2) the spacings of all the epitaxial layers; and 3) the index changes of the optical paths due to injected current. This latter mechanism contributes detrimentally to the phase control of existing semiconductor laser arrays since all existing large arrays have individual elements that are electrically connected. As a result, instabilities between the photon densities and injected current in each element are impossible to control. Although individual current control to each element may be cumbersome and undesirable, with the VCSEL geometry, it is possible to use a patterned submount [G. A. Evans and J. M. Hammer, editors, Surface Emitting Semiconductor Lasers, Academic Press, New York, 1993] to individually control the current to each element. Further, instead of directly controlling the current to each array element, the overall complexity can be reduced and the desired amount of phase control still achieved by independently controlling of groups of subarrays of the VCSELs. The phase change due to gain-induced index variations may be exploited to maintain the array in the “in phase” mode. In principle, with additional care in matching the lattice structure of the epilayers, the surface of the array can be made optically flat. In this variation, the ends of the common waveguide can have high reflectivity coatings and the coherent array emission can be emitted through one of the wafer surfaces. Such surface emission could be from either the VCSEL surface or through a transparent substrate. The naturally occurring surface emission (due to the second-order grating coupling light out of the common waveguide and the undeflected light generated by the VCSELs) can be enhanced with the addition of an anti-reflective coating (in the case of emission through a transparent substrate) and possibly an additional outcoupling grating. Hybrid VCSEL/Waveguide Structure FIG. 2 shows a schematic drawing of a hybrid VCSEL/waveguide structure which includes a VCSEL array 34 and a single common waveguide 24 with a periodic grating 22 , labeled external waveguide coupler 38 . The waveguide 24 is attached to the VCSEL array 34 through mechanical spacers (not shown). Optical coupling between the array elements 34 is provided by the grating coupled waveguide 34 . An optical waveguide 24 with a series of gratings 22 allows the distribution and coupling of light into and out of individual VCSEL elements 36 , thereby locking each element into a coherent, single frequency array mode. Light from each VCSEL 36 is coupled by the grating coupler 38 and diffracted equally to the left and to the right of each grating 22 . The grating coupler 38 is designed to separate first-order modes and couple these modes into the waveguide 24 . The waveguide 24 allows the light to travel in either direction. The first-order diffracted light can be transmitted through the grating 22 and reflected back from the grating 22 . The light can be also coupled back into the VCSELs 36 for phase locking. As mentioned previously, phase locking can be achieved using the distribution waveguide method by controlling a precise amount of coupling between array elements. This approach is independent of the element size and element spacing. The amount of coupling for phase locking is dependent on the VCSEL element diameter, grating depth, waveguide dimensions, and material compositions. It is estimated that ˜1% of the single pass optical power in the common waveguide can be coupled into each VCSEL element, which is sufficient for phase locking. The grating coupled waveguide provides a linear array of elements which can be extended into a 2D array to produce high-power coherent arrays of VCSELs. Monolithic VCSEL/Waveguide Structure with Top Waveguide Grating Coupler Referring to FIG. 3 , high-power coherent arrays of VCSELs can be achieved using a monolithic VCSEL/waveguide structure which is shown there. A common waveguide 42 with grating couplers 22 is placed above the VCSELs 36 for coupling the output light from the VCSEL array. For this approach, a VCSEL epitaxial structure 40 is first grown using standard growth techniques such as molecular beam epitaxy (MBE) or metalorganic chemical beam epitaxy (MOCVD). An additional layer 42 is grown on top of the VCSEL structure for the waveguide grating coupler. The coupling waveguide surface 44 is holographically exposed and the resulting photoresist grating is etched into the exposed wafer surface 44 . The grating period required to couple the waveguide light into the VCSEL elements Λ is typically ˜0.25 μm. It is calculated from Λ=λ o /η eff , where λ o is the free space wavelength of the laser and η eff is the effective refractive index of the coupling waveguide. Finally, the waveguide layer is epitaxially grown using a regrowth technique. This approach avoids introducing complexity and losses into the basic VCSEL elements, and allows testing the VCSEL elements on a portion of the wafer before the waveguide and grating is fabricated. After the grating fabrication is complete, the remainder of the waveguide is epitaxially grown, where standard n- and p-side metals are applied prior to wafer testing. Monolithic VCSEL/Waveguide Structure with Internal Waveguide Grating Coupler FIG. 4 shows a schematic of a monolithic VCSEL/waveguide structure with an internal grating coupler 46 . The coupling waveguide 46 is integrated between the two DBR mirrors 48 , 50 . To fabricate this structure, the first bottom DBR mirror 48 , active region 52 , and part of the coupling waveguide (up to the grating surface 54 ) is grown. The grating 56 is then fabricated. The top DBR mirror 50 of the VCSEL structure is then grown. One of the potential challenges associated with the monolithic VCSEL/waveguide structure of FIG. 4 , is the requirement of epitaxial regrowth. Regrowth of epitaxial structures is routinely performed for long-wavelength semiconductor lasers with a buried heterostructure design [Besomi, Wilson, Brown, Dutta, and Nelson, Electron. Lett., Vol. 20, pp. 417–8, 1984]. For short-wavelength semiconductor lasers, the presence of AlGaAs layers has limited the use of epitaxial re-growth. The problem is that Al is very reactive and surface oxides can easily form when the sample is exposed to air. This surface oxide is very difficult to remove and in-situ etching is often required prior to regrowth on the AlGaAs interface [Mui, Strand, Thibeault, Coldren, Int. Symp. on Compound Semiconductor, San Diego, Calif., paper no. TUA4.8, 1994]. Another concern with regrowth on the grating coupler is whether the surface would planarize enough to allow for high quality DBR mirrors on top of the grating. As a safety pre-caution, the active region of the VCSEL structure are grown prior to the definition of the grating. It has been found that MOCVD is the best technique to perform a regrowth on the grating coupler 46 in order to ensure a planarized surface. Depending on the depth of the grating coupler 46 , planarization should occur within 0.5 μm of the regrowth material. FIG. 5 is a transmission electron microscope (TEM) image showing the smoothing effects of a GaAs/AlGaAs superlattice growth using MOCVD [Xu, Huang, Ren, and Jiang, Appl. Phys. Lett., Vol. 64, pp. 2949–51, 1994]. The TEM images indicate that the surface roughness (˜0.1 μm height) was planarized within a few superlattice periods. In the case of the grating couplers, the grating depth is on the order of 50 nm; therefore, it is believed that the DBR mirrors grown on top of the grating coupler would be quite smooth. Waveguide Grating Coupler The waveguide grating coupler is a key component of the VCSEL/waveguide grating system. The performance of the system depends largely on the grating coupler. It is of considerable interest to develop predictions of the efficiency of the diffraction process in terms of the waveguide and grating parameters. The coupling efficiency of a grating coupler is dependent on several parameters such as the grating depth, the index modulation of the grating, and the type of grating. Several theoretical models have been developed to calculate the waveguide-grating interactions in terms of the tooth profile, composition, and position of the grating with respect to the optical waveguide. One model uses a modal formulation based on a Floquet-Bloch approach [Hadjicostas, et. el., IEEE JQE, Vol. 26, No. 5, p. 893, May 1990]. An-other model relies on a boundary element method [Evans, et. al., IEEE JQE, Vol. 27, No. 6, p. 1594, June 1991] and allows analysis of arbitrary grating profiles. The predictions of the Floquet-Bloch model have been compared to a complete, self-consistent experimental measurement of the wavelength dependence of reflection, transmission, and outcoupling from a Bragg second-order grating. Comparisons were made with the calculations for 50% duty cycle square-wave gratings with tooth depths equal to the experimentally measured values ranging from 40 nm to 600 nm. Close agreement between the theoretical and experimental results were obtained [Ayekavadi, et. al., SPIE meeting, Los Angeles, January 1991]. FIG. 6 shows a schematic drawing of a waveguide structure where the VCSEL light is coupled through the surface-normal second-order grating coupler 54 . The phase matching condition dictates that the difference between the wavevector of the incident beam and the wavevector of the diffracted beam has to be conserved through the wavevector of the surface grating. As a result of the phase matching condition, the grating period, Λ for the surface normal grating coupler is chosen to be Λ 32 λ o /η eff , where λ o is the wavelength of the incident light and n eff is the effective index of the guided mode [Gary A. Evans and J. M. Hammer, “Surface Emitting Semiconductor Lasers and Arrays”, Academic Press, 1993]. Waveguide Grating Design A typical three-layer waveguide is shown in FIG. 7 . Layer 2 is the waveguide core and layers 1 and 3 are the cladding layers. n i is the refractive index of layer i. Two different waveguide structures were initially examined; asymmetric and symmetric. An asymmetric waveguide has different refractive indices in the cladding layers (n 1 ≠n 3 ), while the refractive indices in the cladding layers are the same in a symmetric waveguide (n 1 =n 3 ). However, an asymmetric waveguide structure was chosen for this program. It was found from the design process that a symmetric waveguide has several disadvantages over an asymmetric waveguide structure. These include the requirement of an extra epitaxial layer growth and a low optical coupling efficiency due to low index difference at the grating interface. The waveguides are designed for both singlemode and multimode operations. The number of modes in the waveguide is dependent on the thickness of the waveguide core layer as well as the index difference between the waveguide and cladding layers. FIG. 8( a ) shows a refractive index profile of an asymmetric waveguide structure which consists of four layers. Layer 1 is the GaAs substrate; layer 2 is the AlGaAs cladding layer; layer 3 is the AlGaAs waveguide core layer; and layer 4 is the air. The thicknesses and compositions of layers 2 and 3 should be determined to satisfy the operational requirements of the waveguide such as operational wavelength and the modal property. Since a majority of the light will be guided in layers 2 and 3 , these layers must be transparent at the VCSEL emission wavelength of 850 nm. This requirement is satisfied if the mole fraction of Al is greater than ˜5%. The thicknesses of layers 2 and 3 should be designed such that the optical fields are not influenced at the interface between layer 1 and layer 2 . In addition, for the wave to be guided, the refractive index of the waveguide core should be greater than that of the cladding layers, layers 2 and 4 . The thicknesses and compositions of layers 2 and 3 are also determined by considering the number of modes in the waveguide. If the refractive index step is too large, layer 3 will have to be very thin to remain singlemode. If the refractive index step is too small, the light will be loosely confined to layer 3 requiring that layer 2 be very thick so that the light is isolated from the lossy GaAs substrate (layer 1 ). To meet all of these constraints, the composition of layer 3 was chosen to have a mole fraction y of Al between 0.15 and 0.2 and the mole fraction x of Al in layer 2 to be between 0.3 and 0.4. A complete solution of the field configuration (modes) for the four-layer waveguide which is shown in FIG. 4 were obtained by solving the wave equations derived from Maxwell's equations with proper boundary conditions at the interfaces. Several important parameters were calculated from the analysis such as the optical confinement factor and the effective refractive index. These parameters were used in designing the waveguide and grating structures for optimal performance. For example, the real and imaginary parts of the effective refractive index were used to determine the grating period and the mode structure, respectively. The confinement factor and the effective refractive index have a strong dependence on the waveguide layer thicknesses and their index differences. Therefore, it is very important to consider these parameters in the design of waveguide and grating. The optical confinement factor is defined as the ratio of the optical power in a layer to the total mode power. The confinement factor for the ith layer, Γ i is given by Γ i = ∫ i ⁢  E ⁡ ( x )  2 ⁢ ⅆ x ∫ - ∞ + ∞ ⁢  E ⁡ ( x )  2 ⁢ ⅆ x ( 1 ) where E(x) is the transverse field distribution in the waveguide structure and the integral in the numerator is performed over the width of the ith layer region. Since the coupling efficiency of the grating coupler is related to the field at the grating region, it is important to consider the field distribution in order to determine the fraction of the optical power within the grating layer. The grating layer will be etched into layer 3 . FIG. 9 shows the optical confinement factor of the four-layer waveguide which is shown in FIG. 8( a ) for different cladding layer thickness d 2 (layer 2 ) of 1.5 μm and 2.0 μm. The confinement factor in each layer is illustrated as a function of the waveguide core thickness d 3 Layer 2 has an Al mole fraction of either 0.3 or 0.4 and layer 3 has an Al mole fraction of either 0.15 or 0.2. The Table of FIG. 8( c ) shows the refractive index values, at a wavelength of 0.85 μm used in this calculation. The variation of optical confinement with the waveguide layer thickness for d 2 of 1.5 μM is shown in FIGS. 9( a )–( c ) where (a), (b), and (c) are the confinement factors for the waveguide core, cladding layer, and air, respectively. From these figures, it is clear that there is a strong dependence of the optical confinement in each layer on the waveguide layer thickness. As shown in FIG. 9( a ), a significant increase in confinement occurs when d 3 is increased. As d 3 becomes larger, the light is confined more into the waveguide core and more of the total intensity is within the core layer. When layer 3 is thicker than ˜0.6 μm to 0.8 μm, a majority of the mode power is within layer 3 . In addition, the refractive index difference between layers 2 and 3 has a strong effect on the confinement factor. The greater the index difference, the greater the confinement factor. For example, an index difference Δn is 0.15 for x=0.4 (layer 2 ) and y=0.15 (layer 3 ), while Δn is 0.06 for x=0.3 and y=0.2. Therefore, the confinement factor of the former case is larger than that of the latter case. This is because the guided optical power is increased with the index difference between the waveguide core and cladding layers. Unlike the waveguide core layer, the optical confinement in the cladding layer (layer 2 ) is considerably reduced with d 3 , as shown in FIG. 9( b ). If layer 3 is very thin, most of the optical power is spread into the AlGaAs cladding layer (layer 2 ). In FIG. 5( c ), the confinement factor for layer 4 (the air region) is shown as a function of d 3 . Since the grating coupling coefficient is proportional to the product of the field intensity at the grating and the index difference between layers 3 and 4 , it is expected that the most optical coupling to the external waveguide occurs when the confinement factor of layer 4 is near a maximum. FIGS. 9( d )–( f ) show the confinement factor for the cladding layer thickness d 2 of 2 μm. The confinement factor shows a trend similar to the case of d 2 of 1.5 μm. As d 3 increases, the confinement in layer 3 is considerably increased and rapidly saturated with a small value of d 3 ( FIG. 9( d )). When compared to FIG. 9( a ), the confinement factor in layer 3 for large d 2 (2 μm) is a little bit larger than that for d 2 of 1.5 μm. In contrast, the optical confinement in layer 2 is significantly reduced with d 3 , as shown in FIG. 9( d ). This is because as d 3 increases, more of the light intensity is confined to layer 3 . From the solutions of the wave equations, the effective refractive index of an asymmetric waveguide structure can be obtained by considering the propagation constant in the waveguide. The effective refractive index is calculated by the ratio of the wave propagation constant in the waveguide to the free space wave number. This effective index can be complex depending on the parameters of the waveguide structure. FIGS. 10( a ) to 10 ( d ) show the effective refractive index of the asymmetric waveguide which is shown in FIG. 8( a ) as a function of layer 3 , with Al compositions fixed to 0.3 and 0.4 for layer 2 and 0.15 and 0.2 for layer 3 . In FIGS. 10( a ) and ( b ), the loss in the waveguide, which can be related to the imaginary part of the effective index, is illustrated for d 2 of 1.5 μm and 2 μm, respectively. The non-zero values of loss indicate that the optical mode power decays exponentially as the wave propagates in the waveguide and therefore the optical mode is cut-off. If the thickness of layer 3 is too small, then there will be no bound modes. The cut-off thickness of layer 3 for the fundamental TE 0 mode ranges from ˜0.2 μm to 0.4 μm depending on the compositions of layers 2 and 3 . Alternatively, if the thickness of layer 3 is greater than ˜0.6 μm to 1 μm, a higher-mode TE 1 mode will appear. As shown in FIGS. 10( a ) and ( b ), there is a thickness range over which this asymmetric waveguide will operate as a singlemode waveguide. In FIGS. 10( c ) and ( d ), the real part of the effective refractive index, η eff shown as a function of the thickness of layer 3 for d 2 of 1.5 μm and 2 μm, respectively. Only the index values for the fundamental waveguide mode TE 0 are shown. The real part of the effective index was used in the calculation of the grating period. The grating period Λ was chosen to be Λ=λ 0 /η eff where λ o is the free space wavelength of the incident light. From the theoretically calculated results for an asymmetric waveguide, the strongest grating confinement and hence a large optical coupling can be achieved with an asymmetric waveguide with a layer 3 Al mole fraction of 0.15 and a layer 2 Al mole fraction of 0.4. The thickness of the waveguide core layer is then determined mainly by the requirements of optical modal properties such as singlemode or multimode operation. First the design of a singlemode asymmetric waveguide will be considered with an optimum grating parameters to achieve high coupling efficiency. When a grating is etched into the asymmetric waveguide which is shown in FIG. 8( a ), there will be a grating layer at the interfaces between the high index waveguide core and air. The grating layer is treated as a fifth layer. Therefore, the complete waveguide is composed of the GaAs substrate, an AlGaAs cladding layer, an AlGaAs waveguide core layer, a grating layer, and air. FIG. 11 shows the refractive index profile of this structure at 0.85 μm, with Al compositions are fixed to 0.4 and 0.15 for layers 2 and 3 , respectively. The refractive index of the grating layer is given by the geometric mean of the indices of the waveguide core and air. Since the grating is etched into layer 3 , the thickness of layer 3 decreases as the thickness of the grating layer increases. The sum of the thicknesses of the grating layer and layer 3 is a constant and is referred to as the “total thickness”. FIG. 12 is a plot of the grating confinement factor as a function of the thickness of the grating layer for an Al mole fraction of 0.15 in layer 3 and 0.4 in layer 2 . The total thickness of the grating layer and layer 3 ranges from 0.5 μm to 1 μm. From this figure, it is clear that the grating confinement factor increases substantially as the total thickness is reduced. However, for the total thickness of 0.5 μm, there is an optimum range for the grating thickness. In this case, the maximum grating confinement factor of 0.015 can be achieved at the total thickness of ˜0.28 μm. Since the coupling efficiency is directly proportional to the grating confinement factor, the maximum coupling occurs at this peak. FIG. 13 exhibits the calculated results of the optimized asymmetric waveguide structure for singlemode operation at 0.85 μm. Al mole fractions of layers 2 and 3 are assumed to be 0.4 and 0.15, respectively. The grating confinement factor is shown as a function of the grating depth for various total thicknesses of layer 3 . The grating confinement factor for each case has a similar dependence on the grating depth. The optimum grating depth that results in the maximum coupling increases with the total thickness. In FIGS. 14( a ) and 14 ( b ), the real part of the effective refractive index, FIG. 14( a ), and the grating period, FIG. 14( b ), of the optimized waveguide are plotted versus the grating depth. The optimized asymmetric waveguide used an Al mole fraction of 0.4 for layer 2 and an Al mole fraction of 0.15 for layer 3 . The grating period was calculated using the real part of the effective index, as described previously. Since the real part of the effective index is reduced with the grating depth, the grating period is increased with the grating depth (grating period is inversely proportional to the real part of the effective index). For the total thickness of 0.5 μm, the grating period is ˜0.251 μm. A multimode asymmetric waveguide grating coupler was also designed for a laser emission wavelength of 850 nm. The number of optical modes in the waveguide depends on both the thick-ness and the index difference between the waveguide and cladding layers. The number of modes can be approximately calculated from the following equation: m = 1 π ⁡ [ k o ⁢ d 3 ⁢ n 3 2 - n 2 2 - tan - 1 ⁡ ( n 3 2 - n 4 2 n 3 2 - n 2 2 ) ] ( 2 ) where k o is the free space wave number and n i is the refractive index of layer i. This equation was derived by assuming a three-layer asymmetric waveguide which consists of the cladding layer (layer 2 ), the waveguide core (layer 3 ), and the air (layer 4 ). From FIGS. 9( a ) to 9 ( f ), it can be deduced that the field intensity is negligibly small in the GaAs substrate since a majority of the light is confined in layers 2 and 3 . As a result, the GaAs substrate can be neglected. FIG. 15 shows the number of TE modes in the asymmetric waveguide versus d 3 for respective Al mole fractions of 0.4 and 0.15 for layers 2 and 3 . Singlemode operation can be achieved over the ranges between ˜0.17 μm and 0.59 μm. It is expected from Equation 2 that as the thickness of layer 3 increases, the number of modes in the waveguide increases. For example, there are 19 TE modes in the asymmetric waveguide if layer 3 is 8 μm thick. In FIG. 16 , the calculated results for a multimode asymmetric waveguide grating coupler is illustrated for different total thickness of layer 3 : 6 μm, 8 μm, and 10 μm. The grating confinement factor is shown as a function of the grating depth for a multimode asymmetric waveguide with a mole fraction of 0.15 in layer 3 and a mole fraction of 0.4 in layer 2 . The total thickness of layer 3 and the grating layer is fixed for each curve. The confinement factor increases initially with the grating depth, but it is saturated rapidly at the grating depth of ˜1 μm. Therefore, the grating depth of >1 μm does not further increase the optical confinement in the grating region. As the mode order increases with total thickness, more of the light intensity is confined to layers 2 and 3 . Therefore, the lower the mode order, the greater the confinement factor. When compared to a singlemode waveguide structure, the confinement factor for the multimode waveguide is much smaller. From the propagation constant in the waveguide, the effective refractive index was calculated. FIG. 17( a ) shows the real part of the effective index as a function of the grating depth. The total thickness of layer 3 and grating layer is fixed for each curve: 6 μm, 8 μm, and 10 μm. In FIG. 17( b ), the grating period is plotted versus the grating depth for different total thicknesses. The grating period was calculated from the real part of the effective index. Scattering Characteristics of Waveguide Grating A schematic diagram of the waveguide grating coupler structure of the present invention is shown in FIG. 18 . The waveguide has a finite-length grating that is etched onto an AlGaAs guide layer with an Al mole fraction of 0.15. The optical modes propagating from left to right are designed so that a majority of the optical power is confined to the guide layer. Since the waveguide is highly asymmetrical, in terms of the refractive index values of the layers surrounding the guide layer, much of the modal power will reside in the guide layer. In fact, the fraction of modal power that “feels” the grating will be small because of “leakage” to the cladding layer. It was assumed that an optical mode propagates from left to right. When the mode reaches the grating region, some power will be scattered at the interface of the “ungrated waveguide” and the “grated waveguide”. The calculations which follow neglect the interface discontinuities because the scattered power can be minimized by proper design of the grated and ungrated waveguides. The objective of the present invention is to couple light between the optical guide layer and a surface emitting laser that is just above the grating region of FIG. 18 . Conversely, light from the surface emitting laser can be coupled to the guide layer. Accordingly, the light from the laser and the waveguide will couple in a unique fashion. In order to analyze the combination, it is only necessary to determine the scattering characteristics of the finite section of the grated waveguide. To couple several sources, the “unit cell” shown in FIG. 14 can be extended along the lateral direction. Analysis can be satisfactorily obtained from the scattering matrix of the unit cell. The cross-section of the waveguide shows that grating 56 is etched onto the main guide layer 56 that is surrounded by cladding layer 58 below and an air layer above. The guide layer 56 has a refractive index value of n=3.5101468 while the cladding layer 58 has n=3.3601311. All refractive index values are for a free-space wavelength λ=0.85 μm. The cladding layer 58 has a thickness of 0.4 μm while the guide layer 56 thickness is 0.4 μm and the grating depth is 0.1 μm. It is assumed that the total thickness of the grating and waveguide layer is 0.5 μm. The refractive index profile of the asymmetric waveguide shown in FIG. 18 is illustrated in FIG. 19 . The grating starts at x=0 and extends to x=the grating depth. The figure shows that the index of refraction of the grating regions has a value of ˜2.5. This value is obtained by taking the average of the refractive index of the material of the guide layer and that of air. This estimated value of the index can be used to approximate the axial propagation constant of the Floquet-Bloch mode propagating the dielectric region of the structure. The waveguide section of FIG. 18 can be analyzed using the circuit model which is shown in FIG. 20 . Note that optical power will be directed from the left waveguide. As light propagates in the grating, there will be power scattered in four directions: (a) the grating will scatter light into air above the grating (b) light will scatter below the grating into air (c) light will be reflected backward (d) light will be transmitted to the waveguide to the right side of the grating. The powers radiated in the up and down directions are computed using Poynting vectors. The up and down powers are computed by integrating the upward (or downward) component of the Poynting vector over the grating length L. Only the fast-wave space harmonics around the second Bragg are needed for the radiated power calculation. The scattered powers are shown in FIG. 21 . The grating depth is 0.1 μm while the waveguide and cladding layer thickness are 0.4 μm. The second Bragg detuning parameter is equivalent to sin θ, where θ characterizes the direction of radiation relative to the normal of the waveguide. For example, when the Bragg detuning parameter is 0.005, the radiation will be directed at θ=0.005 rad. This is because sin θ is approximately θ. The waveguide whose length L=10 μm exhibits very little dispersion about the second Bragg. ˜8% of the input power is radiated in the upward direction, while 2% is lost to the region below the guide. The grating of length L=10 μm produces very little reflected power, while the transmitted power is ˜90%. Because of the reciprocity condition, light from a source above the grating will couple ˜8% into one direction in the waveguide. This corresponds to ˜16% total (left and right directions.). Because the grating acts as a four port network, the grating region can be characterized as a four port network as shown in FIG. 22 . The circuit model of the single scattering section can be used to model the performance of a group of cascaded elements. Four-port network can be characterized with its scattering matrix: S = [ S 11 ⁢ S 12 ⁢ S 13 ⁢ S 14 S 21 ⁢ S 22 ⁢ S 23 ⁢ S 24 S 31 ⁢ S 32 ⁢ S 33 ⁢ S 34 S 41 ⁢ S 42 ⁢ S 43 ⁢ S 44 ] ( 3 ) Assuming input is from port 1 , S 11 represents the reflection coefficient, S 12 represents the transmission coefficients to the second port, etc. If the port is lossless, then Sij=S*ji, where * is the complex conjugate. Because of the symmetry conditions between ports 1 and 2 , all scattering elements can be found. The magnitude of the reflection coefficient S 11 is the square root of the reflected power ( FIG. 21( c )), while the magnitude of the transmission coefficient S 12 is the square root of the transmitted power ( FIG. 21( d )). Similarly, the magnitude of the transmission coefficients S 14 and S 13 are determined from transmitted powers (square roots) shown in FIGS. 21( a ) and ( b ), respectively. Although phases of the scattering matrix elements are not shown, their values play key roles in determining the performance of the cascaded circuits. High-power coherent light sources can be achieved by using a VCSEL/waveguide structure. The surface-normal grating coupler is employed to achieve the desired coupling light from the VCSEL into a single common waveguide for phase locking. Three architectures have been proposed to integrate the grating-coupled waveguide with the VCSEL array. These architectures can be utilized to fabricate low-cost, high-power coherent light sources for a variety of military and commercial applications. The present invention has been described above with reference to a grating coupling embodiment. However, those skilled in the art will recognize that changes and modifications may be made in the above described embodiments without departing from the scope of the invention. Furthermore, while the present invention has been described in connection with a specific processing flow, those skilled in the are will recognize that a large amount of variation in configuring the processing tasks and in sequencing the processing tasks may be directed to accomplishing substantially the same functions as are described herein. These and other changes and modifications which are obvious to those skilled in the art in view of what has been described herein are intended to be included within the scope of the present invention.

A high-power coherent array of Vertical Cavity Surface Emitter Lasers is described in which a plurality of Vertical Cavity Surface Emitting Lasers (VCSELs) are provided along with a structure which optically couples each of the VCSELs the plurality of VCSELs to one another by a predetermined amount to cause a coherent mode locking condition to occur. The coupling structure can be a beam cube, a plurality of smaller bean cubes, or a waveguide/grating system, for example. A reference source, or controlled coupling among the VCSELs, is used to phase lock the VCSELs to one another.

TECHNICAL FIELD OF THE INVENTION The field of the invention is in biology and more specifically in the subspecialty of cell biology. BACKGROUND OF THE INVENTION The serum-free culture of normal human epidermal keratinocytes without the use of companion-cells,, cell feeder layer or organotypic substrate, e.g. collagen or gelatin, is disclosed in this invention. Traditionally, tissue culture of normal epithelial cells has been attempted in a variety of commercially available media designed for the growth of less fastidious types of cells, i.e., malignant cells transformed in vitro from cell lines derived from human or nonhuman tissues, cell lines developed from human or nonhuman tumors, or cell lines developed for human or nonhuman embryonic mesenchymal cell types. In contrast, the culture of normal human epithelial stem cells has presented many difficulties not the least of which is the inexorable tendency for these cells to undergo uncontrolled, irreversible, terminal differentiation with the consequent loss of cell division capacity. A significant development which permitted the growth of human epidermal cells in culture was the formulation of a selective basal nutrient medium and its supplementation with specified growth factors and hormones [Tsao, M. C., et al., J. Cellular Physiol. 110:219-229 (1982)]. This selective medium was designated MCDB 152. Further refinements of this medium lead to the formulation of MCDB 153 [Boyce, S. T. and Ham, R. G., J. Invest. Dermatol. 81:33-40 (1983) ]. The use of these media permitted a more accurate characterization of the necessary growth factors, hormones and Ca 2+ requirements for retention of high cloning efficiency necessary to maintain proper genetic programming for continued subculture of pluripotent basal epidermal stem cells [Wille, J. J., et al., J. Cellular Physiol. 121:31-44 (1984)]. The actual role of serum in cell culture medium as a complex mixture of both growth factors and differentiation-inducing factors was resolved by careful clonal growth, cell division kinetics, and flow cytofluorography [Pittelkow, M. R., et al., J. Invest. Dermatol. 86:410-417 (1986) ]. These findings indicated that serum, known to contain fibroblastic cell growth factors, e.g.,, 5 platelet-derived growth factor, was an inhibitor of basal epidermal cell growth. Further, the differentiation-inducing factors in serum could be equated with serum's content of 8-transforming growth factor, (β-TGF) , [Shipley, S. D., et al., Cancer Res. 46:2068-2071 (1986)]. Recently, the inventor and colleagues reported that normal human keratinocytes actually produce their own growth factors. That is, proliferating basal cells are stimulated to secrete α-transforming growth factor (α-TGF) in response to the presence of added epidermal growth factor (EGF) and decrease production of α-TGF at high cell densities near confluence. Under the latter condition, the arrested cells secrete an inactive form of β-TGF [Coffen, R. J., et al. , Nature 328:817-820 (1987)]. These considerations recently led the inventor to the idea that the natural mechanism of growth stimulation and its regulation in intact epidermis involved coordinated secretions of α- and β-TGF's, and that the provision of such factors would eliminate the need for any organic substrate as well. Further experimentation to verify this surmise resulted in the findings in the present invention. Previously, a patent [Green, H. and Kehinde, O., U.S. Pat. No. 4,304,866, 1981] was obtained for an in vitro method for the formation of epithelial sheets from cultured keratinocytes. This method uses a serum-containing medium and a feeder layer of murine (mouse) fibroblast cells to accomplish cell growth and differentiation. This procedure has serious limitations for large scale production of genetically-defined (autologous) human skin substitute. For example, the use of serum inextricably confounds the culture of purely basal cells with the dynamics of serum-induced differentiation. The net result is that subcultivation of such cultures yields low (<5%) clonal efficiencies preventing step-wise large scale build up of uncommitted pluripotent basal cells as a prelude to their conversion into usable sheets of transplantable, histologically-complete, human epidermis. moreover, the process of Green, H. and Kehinde, O. [U.S. Pat. No. #4,304,866, 1981] does not describe a histologically-complete epidermis. i.e. an epidermis which is formed of all six major identifiable layers of a complete human epidermis. Rather, the procedures therein can only form an epidermis lacking a stratum corneum (SEE: FIG. 1E], this being necessary for maximizing the utility of the tissue, and, thus, this limits the product uses. In a more recent methodology, a complete epidermis has been achieved, but only in the presence of a complete skin starter sample and serum-containing media that are combined with an organotypic substratum containing growth factors produced by companion cells [E. Bell, U.S. Pat. No. 4,485,096, 1984; and E. Bell & L. Dubertret, U.S. Pat. No. 4,604,346, 1986]. Although it is conceivable that these latter processes may be used in the absence of serum, the continued use of any organotypic substrate as well as feeder or companion cell types, e.g. fibroblasts, seriously limits, in an immunologically safe manner as well as an economic manner, their large-scale use, e.g. burn patients [Nanchahal, J. , et al., Lancet II (8656) :191-193, (1989)]. In order to remedy these deficiencies the inventor has dispensed with serum-containing media, eliminated any substratum support, dispensed with the requirement for innumerable skin starter samples, and designed a new basal nutrient medium capable of supporting the growth and development of a complete epidermis. Moreover, the identification of essential process steps leading to a functional epidermis has been discovered and can be monitored with specific monoclonal antibodies. In retrospect, the culturing of epidermal keratinocytes in medium containing undefined serum and/or feeder cell factors and/or organotypic substrates, and millimolar concentrations of ca 21 were not designed for the unlimited proliferation of undifferentiated basal cells. Such cultures can spontaneously undergo maturation and uncontrolled differentiation. The result was that an incomplete epidermis was produced. By contrast, the design of serum-free culture process described in this invention produces a complete epidermis by an orderly sequence at will, from a defined starting point in the culture process. SUMMARY OF THE INVENTION There is disclosed the design and formulation of the novel HECK-109 mediums which have been differently supplemented to provide for the serial achievement of the three-step cellular differentiation process of pluripotent basal cell keratinocytes to a fully differentiated human skin in vitro: i] HECK-109, the basal medium for cell starting; ii]HECK-109 fully-supplemented medium (hereinafter referred to as HECK-109PS) for control over cellular growth; iii] HECK-109-differentiation medium (hereinafter referred to HECK-109DM) for the induction of differentiation and formation of a Malpighiian layer (SEE: FIG. 1, A+B)) ; and iv] HECK-109-cornification medium (hereinafter referred to HECK-109CM) designed for the induction of cellular differentiation of a stratum lucidum, stratum corneum and stratum disjunction (SEE: FIG. 1D-F) in a preexisting reformed epidermis produced by HECK-DM. The entire system involves the matter of the sequential rendering of the culture process steps and the method of sequential control in the in vitro construction of a histologically-complete living skin substitute in a totally serum-free medium, feeder layer-free, and matrix-free (collagen or other organotypic matrix) process. This disclosure includes: I a nutrient basal medium designated HECK-109. The critical component concentrations incorporated into this medium design are about: i) (N-[2-OH-ethyl-)piperazine-N'-[2-ethane-sulfonic acid]) (hereinafter referred to as HEPES) at 14-22 mM; ii) NaCl at 90-140 mill; iii) low Ca 2+ level at 0.03-0.3 mM; and iv] six key amino acids of Stock 1 of HECK-109 (SEE: TABLE 1) set at about the following concentrations, Histidine=1.0-2.5×10 -4 M; Isoleucine=0.5-5.0×10 -4 M; Methionine=1.0-5.0×10 -4 M; Phenylalanine=1.0-5.0×10 -4 M; Tryptophan=0.5-5.0×10 -4 M; and Tyrosine=1.0-5.0×10 -4 M. Taken together, Hepes, NaCl, and the six key amino acids are critically superior to any previous media or similar design, in toxicity, osmolarity, and support of clonal growth of basal epidermal cells; II a growth medium for undifferentiated basal keratinocytes based on HECK-109 basal medium and herein designated HECK-109PS. This medium consists of basal nutrient medium HECK-109 supplemented at about the following levels: Ca 2+ =0.3-0.30 mM; hydrocortisone=1.0-5.0×10M; phosphoethanolamine 0.5-2.0×10 -4 M; ethanolamine=0.5-2.0×10 -4 M; epidermal growth factor (EGF)=1-25 ng/ml; insulin-like growth factor-1 (IGF-1)=0.3-30 ng/ml This medium is selective for the growth of normal human epidermal keratinocytes and is essential f or Phase I of the culture growth in that it supports the formation of a hole-free monolayer of undifferentiated keratinocytes while suppressing growth-arrest and any significant decline in clonogenic potential. These properties are unlike any previous media used to support proliferation of basal keratinocytes. The key features of HECK-109FS which make it different and superior to all other keratinocyte growth media are the use of IGF-1 and EGF as the only two protein growth factors used in conjunction with low Ca 2+ (0.03-0.30 mm) ; III a cytodifferentiating growth medium based on basal HECK-109 medium and herein designated HECK-109DM. As detailed in the disclosure, Example 4, the induction of synchronous growth arrest, commitment to terminal keratinocyte differentiation, and formation of a supra-basal cell layer superimposed on top of a proliferation-competent basal cell layer is achieved by replacement of HECK-109FS with HECK-109DM. The latter medium is composed of HECK-109 basal medium supplemented at about the following levels: Ca 2+ =0.7-3.0 mM; hydrocortisone=1-10×10 -7 M; phosphoethanolamine=0.5-2.0×10 -4 M; ethanolamine=0.5-2.0×10 -4 M; EGF=1-5 ng/ml; IGF-1=0.3-30.0 ng/ml; and β-transforming growth factor (β-TGF)=3-30 ng/ml. Addition of β-TGF is a key required to arrest basal keratinocytes through a pathway that prepares the monolayer for induction of stratification, a step under the joint control of EGF (1-5 ng/ml), β-TGF (3-30 ng/ml), and Ca.sup. 2+ (0.7-3.0 mM). HECK-109DM must be replaced by HECK-109CM (Cornification-inducing Medium) to achieve the final steps in the induction of a full-thickness, histologically-complete epidermis; iv a differentiation and cornification medium based on basal HECK-109 medium and herein designated HECK-109cm. This medium is designed to induce the competent formation of a stratum corneum, which also leads to the appearance of a stratum lucidum and stratum disjunction (SEE: FIG. 1D-F) HECK-109CM is based on HECK-109 basal medium and has about the following levels of critical components which achieve this step (in addition to HECK-109 basal medium): linoleic acid=1-15 gg/ml; hydrocortisone=1.0-10.0×10 -7 M; phosphoethanolamine=0.5-2.0×10 -4 M; ethanolamine=0.5-2.0×10 -4 M; and Ca 2+ =0.7-3.0 mM; V a method, including design and formulation of a cell competency solution (herein designated CCS) , whereby clonally competent basal keratinocytes are isolated from human skin samples by the procedures outlined in Example 1. The essence of these steps is the recovery of a unique subpopulation of basal cells which differ from basal cells tightly associated with the dermis. Separation versus tight association is defined as those cells (the unique disassociated subpopulation) which are recovered from treatment of a human skin biopsy with 0.1-0.2 percent trypsin (W/v) dissolved in CCS. CCS is designed to permit the initial isolation of a subpopulation of clonally competent basal keratinocytes that retain a high clonality. This is due to the low toxicity of this medium and improved osmolality which differ from all other isolation solutions for such cells. The approximate composition of ccs is as follows: glucose=10 MM; KCl=3 mill; NaCl 90-140 mill; Na 2 HPO 4 .7H 2 O=1 mill; phenol red=0.0033 mM; HEPES 16-22 mill; 100 Units both of penicillin and streptomycin and SOTI=0.1-1.0 percent (W/v). The isolated subpopulation of competent basal cells are then seeded into HECK-109FS at 5×10 4 cells/cm 2 and are clonally amplified to the density of 2×10 4 to 2×10 5 cells/cm prior to their serial passage into secondary culture, and the clonal growth of said cells; and VI a method wherein the requirements for the preparation and sequential 35 differentiation of a secondary proliferating monolayer of undifferentiated or differentiated keratinocytes are outlined (referred to as Phases I, II, and III). Said procedures include the seeding of clonally competent keratinocytes into HECK-109FS at an initial cell density of about 5×10 2 to 3×10 3 cells/cm 2 and their growth to a density of about 2-4×10 5 cell/cm 2 prior to the induction of differentiation (Phase I) and sequential formation of a histologically-complete stratified epithelium by the controlled progressive and sequential culture of the cells in HECK-109DM (Phase II), and HECK-109CM (Phase III) wherein the final in vitro skin product contains all the layers outlined in FIG. 1. The above description discloses a process that is premised upon the realization that a viable, and completely reformed human epidermis with a stratum corneum [SEE: FIG. 1E) can be entirely reformed in culture by following an orderly sequence of steps hitherto unknown whereby these steps are absent serum, feeder cells or organotypic substrates of any type. Phase I is the culturing of primary normal human keratinocytes in a newly designed serum-free medium [Medium HECK-109). Although the usual procedure for obtaining keratinocytes involves foreskins, adult skin specimens from virtually any body site and of at least 1 to 2 cm 2 (such as a punch biopsy) provides a sufficient number of input cells to start a primary culture. Phase I is capable of amplifying the initial input of cells of the epidermis by a factor of 100,000 by serial subcultivation procedures (secondary cultures), requires less than two weeks, and provides enough basal cells to eventually form about 2 to 3 square meters of histologically complete and viable epidermis. once secondary cultures of basal cells have been amplified in Phase I to the desired extent, the proliferating cultures are stimulated to reach confluence and form a hole-free sheet in the presence of a medium designed to ensure retention of undiminished clonal growth. This supplementation step is crucial. It is achieved by replacing the basal HECK-109 serum-free culture medium with HECK-109 medium enriched in specific amino acids outlined above and linoleic acid. In this latter medium, the basal cells within the monolayer continue to proliferate resulting in the formation of a crowded monolayer, with continued clonal growth capacity until used in Phase II in the process. Phase II in the cell culture process is the induction of identifiable cell strata with the formation of a nondividing suprabasal cell layer, and continued proliferation of the underlying basal cells. These events are simultaneously induced by replacement of the second-step HECK-109 enrichment medium with the basal HECK-109 serum-free medium containing β-TGF (3 to 30 ng per ml), and Ca 2+ (0.7 to 3.0 mM). This medium additionally lacks EGF and IGF-1. Within a few days, the proliferating cell monolayer converts into a stratified epidermis, which then progressively thickens to form a multilayered living sheet of epidermis. This process continues for about a week in culture and completes Phase II of in vitro formation of a human epidermis. At this stage, the epidermis consists of three histologically recognizable and antibody-identifiable cell layers, a bottom-most basal cell layer [SEE: FIG. 1] (A, stratum germinativum), a spinous cell layer (B, stratum spinosum) above it, and a top-most granular cell layer (C, stratum granulosum), but no formation of a cornified stratum (E, stratum corneum), or bordering layers, e.g. D, stratum lucidum and F, stratum disjunction. This development requires a third phase of culture. The second phase culture, characterized by an incomplete epidermis, will persist in culture for an extended period (>30 days). It will, however, lose the capacity to convert to a complete epidermis. This is prevented by initiation of Phase III of culture. The second phase medium is replaced with a first-phase serum-free medium that lacks all added protein growth factors but has elevated Ca 2+ (0.7-3.0 mM) and linoleic acid (1-15 μg/ml) in the medium. The steps in the culture process that convert an incomplete epidermis to a complete epidermis are outlined in FIG. 1. Unlike the characterization of all existing methods and processes the construction of a completely reformed human epidermis in the above manner is vastly superior to any method employing serum-containing media and/or feeder layer support and/or organotypic matrices because it is faster, reproducible and provides a uniform composition to the finished product from an autologous source. It also affords the possibility of intervening at any of the crucial steps in the process in ways that might augment the cellular content of one of the living versus nonliving cell layers. Finally, the ease of amplifying the initial input through rapid serial cell culture makes this the choice method for instituting autografts within the framework of the time constraints operative during therapeutically-assisted recovery of severe burn patients besides being a long term solution in this and other wound healing problems. DESCRIPTION OF FIGURES FIG. 1 of 6 (Wille). Diagram of the major identifiable layers of a complete human epidermis. FIG. 2 of 6 (Wille) . Human foreskin was treated with 0.17 percent trypsin for 16 hours at 40° C. The specimen was then fixed, embedded in paraffin, sectioned and stained with hematoxylin and eosin by standard procedures. Note: cleavage occurs between the basal layer cells and the overlying suprabasal layer cells (see box). Magnification, 1,250X. FIG. 3 of 6 (Wille) . A typical colony that results from a single-celled clone fixed and stained with crystal violet (0.2 percent w/v) after 2 weeks of growth in complete HECK 109 medium. 15 Magnification, 3.3X. FIG. 4 of 6 (Wille). Reformed human stratified squamous epithelium formed at the end of Phase II culture. Magnification, 980X. FIG. 5 of 6 (Wille). A sheet of complete reformed human epidermis released from its attachment to the plastic dish by Type IV collagenase digestion and photographed by dark-field illumination. Magnification, 4.5X. FIG. 6 of 6 (Wille). Competitive inhibition of radiolabelled [ 3 H]-estradiol binding to complete reformed human epidermis by various sex steroid hormones. The amount of radiolabelled estradiol bound to reformed human epidermis in the absence of steroid hormone 30 competitors was 1.6×10 5 counts per minute. DETAILED DESCRIPTION OF THE INVENTION EXAMPLE 1 Primary and Secondary Culture of Normal Human Epidermal Keratinocytes in HECK-109 Serum-Free medium. Isolation of Basal Cells and Primary Cultures - Through extensive experimentation, I have developed HECK-109, a new serum-free medium, and developed methods detailed below for the successful propagation of normal human basal epidermal keratinocytes from either newborn or adult skin. Primary cultures of normal human basal epidermal keratinocytes are started by subjecting full-thickness skin samples to enzymatic digestion. Skin obtained from biopsies or autopsies is first cleaned of adhering subdermal fat and the dermis is reduced to less than 3 mm in thickness. The skin sample is then typically cut into 8 to 12 small pieces (usually 0.5 cm 2 ). These pieces are floated on top of a sterile Cell Competency Solution [CCS; CCS as follows: glucose, 10 MM; KC1, 3 mM; NaCl, 90-140 mM; Na 2 HPO 4 .7H 2 O, 1 mM; phenol red, 3.3 μM; and (N-[2-OH-Ethyl]Piperazine-N'-[2-EthaneSulfonic acid]) or HEPES at 14-22 mM, [SEE: Shipley, G. D. and Ham, R. G., In Vitro 17:656-670 (1981)], additionally containing 0.10-0.20 percent trypsin (w/v), and antibiotics, 100 units/ml of both penicillin and streptomycin. After 14 to 16 hours of digestion at 40° C. the dermis is separated from the epidermis by a split-dermis technique. This is accomplished by inverting the skin sample, i.e., by placing the cornified layer side of the epidermis onto a clean sterile polystyrene surface, as accomplished by existing typical techniques. The epidermis spontaneously detaches, and the dermis is removed with sterile forceps. I have shown that trypsin digestion cleaves the skin along a fracture line which separates some of the basal cells with the dermis, but frees other basal cells lying between the dermis and the fracture line just above the basal cell layer [SEE: FIG. 2]. The trypsin-treated epidermis, so split from the dermis, is enriched for a subpopulation of loosely-associated, clonally competent basal cells. In a series of experiments, I discovered that these loosely-associated basal cells are larger than the basal cells that remain associated with the dermis. Moreover, these larger basal cells are separable by cell sorting procedures using a florescence-activated cell sorting device. They also have a greater colony-forming ability than the dermis-associated basal cells, as demonstrated by clonal growth experiments. The loosely-associated basal cells are collected in ice-cold (0° to 40° C.) CCS containing 0.1-1.0 percent w/v SOTI solution as outlined above, and the cell suspension filtered on ice through a 100 micrometer sized Nylon mesh by sterile procedures. Filtration removes cell aggregates and ensures preparation of a single cell suspension. The cells are pelleted by low speed centrifugation (800×grav, 5 minutes) at 40° C. The above solution is aspirated off and the remaining cells are resuspended by gentle pipetting in CCS, and washed once with ice-cold, serum-free basal nutrient medium (here designated HECK-109; see Example 2 for detailed composition of this medium). The centrifugation step is repeated as above, and the resulting cell pellet is resuspended in 1 to 2 ml of fresh HECK-109 medium. Cell counts are obtained by standard cell chamber counting methods. Primary cultures are initiated into HECK-109 medium supplemented with 0.1 (0.05-0.20) mM ethanolamine; 0.1 (0.05-0.20) MM phosphoethanolamine; 0.5 (0.1- 1.0) μM hydrocortison 0.2 percent (0.1-1.0) of SOTI, w/v. Antibiotics which are added at this time can be removed 2 to 3 days later when the proliferating cell cultures are refed fresh complete medium. The complete growth medium (HECK-109FS) is further supplemented with 10 ng/ml EGF (1-25 ng/ml), and 5 μg/ml IGF-1 (0.3-30 ng/ml). The latter two protein growth factors are added aseptically to the medium. Other medium supplements and media with the above supplements are sterilized through a commercially available membrane filter. The initial seeding density for initiating the primary culture is 5×10 4 basal cells per 75 cm 2 tissue culture flask. Generally, two such flasks are routinely set up from an initial yield of 1 to 2×10 6 cells isolated from a 1 to 2 cm 2 piece of skin. Secondary Culture Procedure - Secondary cultures initiated from either primary cultures or early passage secondary cultures are passaged by enzymatic dissociation of cells. This serial passage technique is not standard. It involves the use of ice-cold 0.02 (0.02-0.20) percent trypsin (w/v) and 0.1 (0.08-0.12) percent 10 ethylenediaminetetraacetic acid (EDTA; W/v) dissolved in CCS to remove the cells from their plastic substrate. The cells are collected in ice-cold 0.2 (0.1-1.0) percent SOTI (w/v) in CCS as detailed above for initiating primary cultures. Typically, secondary cultures are seeded at an initial cell density at a 1000 cells per cm 2 , but lower seeding densities are possible. The procedures for calculating colony forming efficiency (CFE) of the basal cells recovered from the epidermis and used to initiate a primary culture is to set up duplicate primary cultures at 5000 cells per cm 2 as described above, and then to count the number of cells which attach and which later form a colony of at least 8 or more cells three days after seeding the primary culture. By this method, the percent attachment of epidermal cells is 50 to 60 percent of the input cells. The colony forming efficiency ranges between 0.1 to 0.5 percent of the input cells as measured by ocular micrometer grid square counts on living cultures. EXAMPLE 2 Preparation of HECK-109 Basal Nutrient Medium. Some of the novel methods and materials provided by the invention relate to the preparation of a new basal nutrient medium suitable for the large scale amplification of both primary and secondary cultures of normal human keratinocytes, and for conversion of proliferating normal human keratinocyte monolayer cultures to a stratified squamous epithelium applicable to a transplantable skin equivalent. More particularly, Example 2 is directed to the materials and procedures for preparation of a basal nutrient medium (Human Epidermal Cell Keratinocyte, HECK-109), and evidence for its superiority in stimulating epidermal growth by design of the osmolarity, toxicity, and ph-buffering properties of the standard basal medium formulation. Table I, below, details the concentration of components in basal medium, HECK-109. All biochemicals and hormones are from Sigma Chemical Company (St. Louis, Mo., U.S.A.), and all inorganic chemicals are from Fisher Scientific (Pittsburgh, Pa., U.S.A.). All trace elements in Stock T are from Aesor (Johnson Matthey, Inc., Seabrook, NH, U.S.A., Purotronic Grade). EGF may be prepared according to the procedure of Savage, R. C. and Cohen, S. [J. Biol. Chem. 247:7609-7611 (1972)], or purchased from Collaborative Research, Inc., Waltham, Mass. One liter of HECK-109 is prepared in a separate stock solution fashion as described in Table I with respect to Stocks 2 through 10. Medium HECK-109 differs from all other media in the prior art by its Stock 1 amino acids, its concentration of NaCl (113 mm; Range 90-140) and of HEPES (20 mill; Range 14-22). The design of the level of amino acids must include the following 6 amino acids: Isoleucine=0.5-5.0×10 -4 M; Histidine=0.5-2.5×10 -4 M; Methionine=1.0-5.0×10 -4 M; Phenylalanine=1.0-5.0×10 -4 M; Tryptophan=0.5-5.0×10 -4 M; Tyrosine=1.0-5.0×10 -4 M. TABLE I______________________________________Composition of Basal Nutrient Medium HECK-109 Concentration in final mediumStock Component mg/l mol/l*______________________________________ 1 Arginine.HCl 421.4 2.00 × 10.sup.-3 Histidine.HCl.H.sub.2 O 36.1 1.70 × 10.sup.-4 Isoleucine allo-free 33.0 2.50 × 10.sup.-4 Leucine 132.0 1.00 × 10.sup.-3 Lysine.HCl 36.6 2.00 × 10.sup.-4 Methionine 45.0 3.00 × 10.sup.-4 Phenylalanine 50.0 3.00 × 10.sup.-4 Threonine 23.8 2.00 × 10.sup.-4 Tryptophan 40.8 2.00 × 10.sup.-4 Tyrosine 54.0 3.00 × 10.sup.-4 Valine 70.2 6.00 × 10.sup.-4 Choline 20.8 2.00 × 10.sup.-4 Serine 126.1 1.20 × 10.sup.-3 2 Biotin 0.0146 6.00 × 10.sup.-8 Calcium Pantothenate 0.285 1.00 × 10.sup.-6 Niacinamide 0.03363 3.00 × 10.sup.-7 Pyridoxal.HCl 0.06171 3.00 × 10.sup.-7 Thiamine.HCl 0.3373 1.00 × 10.sup.-6 Potassium chloride 111.83 1.50 × 10.sup.-3 3 Folic acid 0.79 1.80 × 10.sup.-6 Na.sub.2 HPO.sub.4.7H.sub.2 O 536.2 2.00 × 10.sup.-3 4a Calcium cloride.2H.sub.2 O 14.7 1.00 × 10.sup.-4 4b Magnesium 122.0 6.00 × 10.sup.-4 chloride.6H.sub.2 O 4c Ferrous sulfate.7H.sub.2 O 1.30 5.00 × 10.sup.-6 5 Phenol red 1.242 3.30 × 10.sup.-6 6a Glutamine 877.2 6.00 × 10.sup.-3 6b Sodium pyruvate 55.0 5.00 × 10.sup.-4 6c Riboflavin 0.03764 1.00 × 10.sup.-7 7 Cysteine.HCl 37.6 2.40 × 10.sup.-4 8 Asparagine 13.2 1.00 × 10.sup.-4 Proline 34.53 3.00 × 10.sup.-4 Putrescine 0.1611 1.00 × 10.sup.-6 Vitamin B.sub.12 0.407 3.00 × 10.sup.-7 9 Alanine 8.91 1.00 × 10.sup.-4 Aspartic acid 3.99 3.00 × 10.sup.-5 Glutamic acid 14.71 1.00 × 10.sup.-4 Glycine 7.51 1.00 × 10.sup.-410 Adenine 12.16 9.00 × 10.sup.-5 Inositol 18.02 1.00 × 10.sup.-4 Lipoic acid 0.2063 1.00 × 10.sup.-6 Thymidine 0.7266 3.00 × 10.sup.-6Trace Copper sulfate.5H.sub.2 O 0.00025 1.00 × 10.sup.-9Element Selenic acid 0.00387 3.00 × 10.sup.-8T Magnesium sulfate.5H.sub.2 O 0.00024 1.00 × 10.sup.-9 Sodium silicate.9H.sub.2 O 0.1421 5.00 × 10.sup.-7 Ammonium 0.00124 1.00 × 10.sup.-9 molybdate.4H.sub.2 O Ammonium vanadate 0.00059 5.00 × 10.sup.-9 Nickel chloride.6H.sub.2 O 0.00012 5.00 × 10.sup.-10 Stannous chloride.2H.sub.2 O 0.000113 5.00 × 10.sup.-10 Zinc chloride.7H.sub.2 O 0.1438 5.00 × 10.sup.-7Solids Glucose 1081.0 6.00 × 10.sup.-3 Sodium acetate.3H.sub.2 O 500.0 3.70 × 10.sup.-3 Sodium bicarbonate 1176.0 1.40 × 10.sup.-2 Sodium chloride 6600.0 1.13 × 10.sup.-2 HEPES 4700.0 2.00 × 10.sup.-2______________________________________ *All above components come together to a final volume of 1 liter of distilled and 0.22 μmfiltered water. The indicated concentrations of these 6 amino acids have been shown by the inventor to be necessary for sustained basal cell proliferation. By further experimentation, the inventor showed that superior growth occurs when the osmolarity of the basal nutrient medium is 300 (275-325) milliosmoles (mOsM). Finally, through an extensive series of clonal growth experiments in which the osmolarity was held constant at 300 mOsM and the concentration of HEPES varied between 14 to 28 mM it was discovered that the design of HECK-109 must incorporate HEPES at 20 MM (14-22 MM); this is critical to its function with the other ingredients. Table II presents typical results of clonal growth experiments showing that the design of HECK-109 supports a higher growth rate and a higher colony forming efficiency than a standard MCDB 153 commercial medium. At this point, I wish to stress those novel aspects of the HECK-109 basal nutrient medium and, to discuss subsequent discoveries. The most significant discovery is that the concentration of HEPES (20 mM) in HECK 109 medium results in a 2 to 3 fold higher colony forming efficiency than that previously attainable. The second discovery is that an osmolarity of 300 mOsM of the medium permits attainment of higher saturation densities at confluence of monolayer culture. The third discovery is that it is necessary to provide the indicated concentrations of 6 key amino acids present in Stock 1 (2 to 5 times higher concentration than that in commercially available in MCDB 153 medium). This allows normal human keratinocyte cultures to routinely achieve a cell density equal to or greater than 100,000 cells per cm 2 . Media HECK-109 incorporates these three discoveries in such a way that the newly designed formulation will now fully support the formation of a complete reformed human epidermis as detailed below. TABLE II______________________________________Effect of Osmolarity and HEPES Concentrations on theGrowth Response of Normal Human Keratinocytes Growth ResponseCulture HEPES NaCl Osmolarity (Colonies/dish)media (mM) (mM) (mOsM) AHK.sup.a NHK.sup.b______________________________________MCDB-153 28 130 340 84 ± 12 275 ± 24HECK-109 23 104 300 196 ± 23 438 ± 35______________________________________ .sup.a Secondary cultures of adult skin normal human keratinocytes (AHK) were seeded at 2 × 10.sup.3 cells/dish in MCDB l53 medium, and refe HECK109 48 hours later. Dishes were fixed for colony counts 6 days later. .sup.b Clonal growth experiments were performed on neonatal foreskin secondary normal human keratinocytes (NHK) cultures as described in Wille J.J., et al., J. Cellular Physiol. 121:31-44 (1984). EXAMPLE 3 Clonal Growth Studies Employing Single Cell Clones in HECK-109 Medium. Normal human keratinocyte cultures were routinely initiated, from either foreskin or adult female breast skin, as detailed above in Example 1, and then placed into secondary culture in complete HECK-109FS medium. The purpose of the following experiment was to determine the colony forming ability of individual keratinocyte stem cells obtained from different skin donors and from different passage levels of the same normal human keratinocyte sample. It is stressed here that each culture was established from a single genetic source to ensure that the responses observed represent only deliberate experimental manipulations. The technique of cloning individual cells was accomplished by seeding 1000 cells from a exponentially dividing parent culture into a 100 MM 2 Petri dish containing prewarmed HECK-109FS medium. The dish had been pre-seeded with a large number of sterile cloning chips (0.4 CM 2 , Bellco Glass Company, Vineland, N.J., U.S.A.) . Individual glass chips were screened microscopically with an inverted phase contrast microscope and only those bearing a single cell were selected and placed into a sterile 35 cm 2 petri dish and refed fresh HECK-109FS medium. Visual observations of each such single cell isolate were made and a daily record of the number of cells formed from each single-celled clone. The results of these experiments are illustrated in FIG. 3 and Tables III and IV. The data show that each proliferating basal cell from a given donor culture has an exceedingly high clonogenic potential. Typically, a clone is comprised of more than 1000 cells, indicating that the original single cell had undergone more than 10 doublings. Such clones are, by definition, basal stem cells and data on their clonal analysis is presented in Tables III and IV. The results in Table III show that 70 percent of single cells derived from a third passage neonatal foreskin normal human TABLE III______________________________________Comparison of the Proliferative Potential of IndividualAdult Versus Neonatal Keratinocyte Basal CellsPrior Culture Condition.sup.a, bClone Passage Density Average % ProliferativeNo. No. (10.sup.4 /cm.sup.2) GT (hrs) Clones (N)______________________________________Adult 3 0.4 48 48 (109)Neonatal 3 7.5 24 70 (106)______________________________________ .sup.a GT is defined as the average population doubling time (in hours) o the culture. .sup.b N is the number of single cell clones tested. TABLE IV______________________________________Clonal Analysis of the Proliferative Potentialof Individual Keratinocyte Basal CellsNeonatal Prior Culture Condition.sup.a,bClone Passage Cell density Average % ProliferativeNo. level (10.sup.4 /cm.sup.2) GT(hr) Clones(N)______________________________________1 2 1.87 24 (5).sup.c 75 (32)1 3 1.73 24 (6) 66 (35)2 2 1.0 24 (4) 79 (34)3 2 1.1 24 (6) 68 (37)4 2 0.65 30 (4) 51 (93) Mean %=63 (231)______________________________________ .sup.a GT is defined as the average population doubling time (in hours) o the culture. .sup.bN is the number of single cell colonies tested. .sup.cThe number in parentheses within this column indicates the age of the parent culture in days. keratinocyte cultures were, in fact, keratinocyte stem cells. Adult-derived normal human keratinocyte secondary cultures also at the third passage level had a significantly reduced clonogenic potential (48 percent) , which correlates with the slower growth rate (48 hour doubling time) of the parent culture, which when compared with the rapid (24 hour doubling time) of the neonatal foreskin normal human keratinocyte culture clearly shows that the proliferative potential of stem cells is determined by prior culture conditions. Table IV presents data comparing five different neonatal foreskin normal human keratinocyte cultures and shows again, the fact that a consistently high clonogenic potential is maintained in secondary cultures under prior culture conditions. In summary, the combined results of 231 single cells cloned at random from secondary cultures reared IN HECK-109FS medium showed that at least 63 percent were keratinocyte stem cells. The results of these single cell clonal studies indicate that the novel basal medium HECK-109 supports increased clonal growth of basal cells and enhances their clonogenic potential 10 times above the reported values obtained by Green, H. and Rheinwald, J. [U.S. Pat. No. 4,016,0360, 1980] or in the serum-free culturing process of Boyce, S. T. and Ham, R. G. [U.S. Pat. No. #4,673,649, 1986]. These considerations are of utmost relevance to the claims of this patent and for the purpose of obtaining a commercially usable in vitro manufactured living skin substitute. EXAMPLE 4 Steps for the Formation of a complete Epidermis in the Serum-Free HECK-109 Culture Medium. The formation of a complete reformed human epidermis in serum-free HECK-109 medium is accomplished in three separate culture phases. Phase I of culture begins with the seeding of basal keratinocyte stem cells into culture dishes (the number and size of the culture dishes is only limited by the absolute number of cells obtained in the preceding normal human keratinocyte early passage culture) at a cell density of approximately a 1000 cells per cm 2 . Typically, several million keratinocyte stem cells can be prepared from a single primary culture flask, representing about a 5000-fold increase in cells over the starting stem cells recovered from the skin sample. All normal human keratinocyte cultures are fed complete HECK-109FS medium, i.e., basal HECK-109 supplemented with phosphoethanolamine=0.1 MM (0.05-0.20) ethanolamine=0.1 mM (0.05-0.20) ; hydrocortisone=0.5 μM (0.1-1.0); EGF=10 ng/ml (1-25); IGF-1=5 ng/ml (0.3-30.0). Cultures are refed fresh medium every other day until the cell density equals 1 to 2×10.sup. 4 cells per cm 2 . The cultures are then refed HECK-109FS medium containing the following six key amino acids: Histidine=1.7 (0.5-2.5)×10 -4 M; Isoleucine=2.5 (0.5-5.0)×10-4M; Methionine=3.0 (1.0-5.0)×10-4M; Phenylalanine=3.0 (1.0-5.0)×10 -4 M; Tryptophan=2.0 (0.5-5.0)×10-4M; and Tyrosine=3.0 (1.0-5.0)×10M. Cultures refed this medium every other day routinely reach confluence in 6 to 10 days. Phase II, the induction of B, the stratum spinosum and C, the stratum granulosum and concomitant maintenance of the stratum germinativum [SEE: FIG. 1A, the basal cell layer], begins with the removal of the amino acid-enriched HECK-109FS medium and its replacement with complete amino acid-enriched HECK-109DM medium containing 0.7 to 5 mM Ca 2+ and β-TGF (3 to 30 ng/ml). The removal of any one of the media and its replacement with another media is preferably accomplished by any of the common, well-known ways culture media are replaced, such as by aspiration accomplished under sterile conditions. This treatment in low density culture results in a parasynchronous growth arrest in the G 1 phase of the cell cycle [Shipley, G. D., et al., Cancer Res. 46:2068-2071 (1986) and Wilke, M., et al., Amer. J. Pathol. 131:171-181 (1988)]. However, the addition of β-TGF to proliferating monolayer cultures which have attained confluence and which are still dividing, induces, within 48-96 hr, a progressive stratification of the basal cells to form a multilayered epithelium. Concomitantly, the clonogenic potential of the culture declines to approximately 50 percent. By the combined addition of β-TGF, and EGF, a fraction of the dividing basal cells is repressed, and the remaining basal cells, which have already entered into the succeeding cell cycle, are committed to form suprabasal cells. The latter progressively enlarge, differentiate into cell types representative of the spinous and granular cell layers, and migrate to the upper layers of the multilayered epidermis where they are shed into the medium. The result of this differentiation process is the formation of an extended sheet of multilayered epidermis [end of Phase II cell culture; SEE: FIG. 4). This process takes several days to a week to complete, and results in an incomplete living epidermis comprised of a basal cell layer with an overlying Malpighiian cell layer (A, stratum germinativum+B, stratum spinosum). The final step of the of culture process (Phase III) converts the incomplete epidermis to a complete human epidermis by induction 25 in the uppermost layers of a cornified cell layer [stratum lucidum (SEE: FIG. 1D), stratum corneum, [SEE: FIG. 1E] and stratum disjunction (SEE: FIG. 1F) . This step is accomplished by removal of the amino acid-enriched HECK-109DM medium containing β-TGF, EGF and 0.7 to 5 mM Ca 2+ and its replacement with HECK-109CM, i.e. amino acid-enriched basal HECK-109 medium supplemented with 0.7 or 5 mM Ca 2+ , 5 μg linoleic acid (1-15 μg/ml) ; 0.1 mM phosphoethanolamine (0.05-0.20 mm); 0.1 mM ethanolamine (0.05-0.20 mM) ; and 0.5 μM hydrocortisone (0.1-1.0 μM) . During Phase III of culture, granular cells continue to mature into into cornified, anucleate cells which form the topmost layer of the completed epidermis [SEE: FIG. 1]. Thus it can be appreciated from the foregoing that this invention discloses a method for the formation of a histologically-complete skin substitute comprising the steps of: 1) feeding basal keratinocyte stem cells a medium comprising N-[2-OH-ethyl-]piperazine-N'-[2-ethane-sulfonic acid] in a concentration in the range of 14 mM to 22 mM, sodium chloride in a concentration in the range of 90 mM to 140 mM, calcium 2+ ion in a concentration in the range of 0.03 mM to 0.3 mM, histidine in a concentration in the range of 1.0×10 -4 M to 2.5×10 -4 M, isoleucine in a concentration in the range of 0.5×10 -4 M to 5.0×10 -4 M, methionine in a concentration in the range of 1.0×10 -4 M to 5.0×10 -4 M, phenylalanine in a concentration in the range of 1.0×10 -4 M to 5.0×10 -4 M, tryptophan in a concentration in the range of 0.5×10 -4 M to 5.0×10 -4 M, tyrosine in a concentration in the range of 1.0×10 -4 M to 5.0×10 -4 M, hydrocortisone in a concentration in the range of 1.0×10 -7 M to 5.0×10 -7 M, phosphoethanolamine in a concentration in the range of 0.5×10 -4 M to 2.0×10 -4 M, ethanolamine in a concentration in the range of 0.5×10 -4 M to 2.0×10 -4 M, epidermal growth factor in a concentration in the range of 1 ng/ml to 25 ng/ml, and insulin-like growth factor-1 in a concentration in the range of 0.3 ng/ml to 30 ng/ml; 2) the replacement of the preceding medium with a medium comprising N-[2-OH-ethyl-]piperazine-N'-[2-ethane-sulfonic acid] in a concentration in the range of 14 mM to 22 mM, sodium chloride in a concentration in the range of 90 mM to 140 mM, calcium 2+ ion in a concentration in the range of 0.7 mM to 3.0 mM, histidine in a concentration in the range of 1.0×10 -4 M to 2.5×10 -4 M, isoleucine in a concentration in the range of 0.5×10 -4 M to 5.0×10 -4 M, methionine in a concentration in the range of 1.0×10 -4 M to 5.0×10 -4 M, phenylalanine in a concentration in the range of 1.0×10 -4 M to 5.0×10 -4 M, tryptophan in a concentration in the range of 0.5×10 -4 M to 5.0×10 -4 M, tyrosine in a concentration in the range of 1.0×10 -4 M to 5.0×10 -4 M, hydrocortisone in a concentration in the range of 1.0×10 -7 M to 10.0×10 -7 M, phosphoethanolamine in a concentration in the range of 0.5×10 -4 M to 2.0×10 -4 M, ethanolamine in a concentration in the range of 0.5×10 -4 M to 2.0×10 -4 M, epidermal growth factor in a concentration in the range of 1 ng/ml to 5 ng/ml, insulin-like growth factor-1 in a concentration in the range of 0.3 ng/ml to 30 ng/ml, and Beta-transforming growth factor in a concentration in the range of 3.0 ng/ml to 30 ng/ml; and 3) the replacement of the preceding medium with a medium comprising N-[2-OH-ethyl-]piperazine-N'-[2-ethane-sulfonic acid] in a concentration in the range of 14 mM to 22 mM, sodium chloride in a concentration in the range of 90 mM to 140 mM, calcium 2+ ion in a concentration in the range of 0.7 mM to 3.0 mM, histidine in a concentration in the range of 1.0×10 -4 M to 2.5×10 -4 M, isoleucine in a concentration in the range of 0.5×10 -4 M to 5.0×10 -4 M, methionine in a concentration in the range of 1.0×10 -4 M to 5.0×10 -4 M, phenylalanine in a concentration in the range of 1.0×10 -4 M to 5.0×10 -4 M, tryptophan in a concentration in the range of 0.5×10 -4 M to 5.0×10 -4 M, tyrosine in a concentration in the range of 1.0×10 -4 M to 5.0×10 -4 M, linoleic acid in a concentration in the range of 1 microgram/ml to 15 microgram/ml, hydrocortisone in a concentration in the range of 1.0×10 -7 M to 10.0×10 7 M, phosphoethanolamine in a concentration in the range of 0.5×10 -4 M to 2.0×10 -4 M, and ethanolamine in a concentration in the range of 0.5×10 -4 M to 2.0×10 -4 M. More preferably, the method for the formation of a histologically-complete skin substitute includes in the first step the concentration of N-[2-OH-ethyl-]piperazine-N'-[2-ethane-sulfonic acid] in the range of 14 mM to 22 mM, the concentration of sodium chloride in the range of 90 mM to 140 mM, the concentration of calcium 2+ ion in the range of 0.1 mM to 0.15 mM, the concentration of histidine in the range of 1.0×10 -4 M to 2.5×10 -4 M, the concentration of isoleucine in the range of 0.5×10 -4 M to 5.0×10 -4 M, the concentration of methionine in the range of 1.0×10 -4 M to 5.0×10 -4 M, the concentration of phenylalanine in the range of 1.0×10 -4 M to 5.0×10 -4 M, the concentration of tryptophan in the range of 0.5×10 -4 M to 5.0×10 -4 M, the concentration of tyrosine in the range of 1.0× 10 -4 M to 5.0×10 -4 M, the concentration of hydrocortisone in the range of 1.0×10 -7 M to 2.0×10 -7 M, the concentration of phosphoethanolamine in the range of 0.7×10 -4 M to 1.5×10 4 M, the concentration of ethanolamine in the range of 0.7×10 -4 M to 1.5×10 -4 M, the concentration of epidermal growth factor in the range of 1 ng/ml to 5 ng/ml, and the concentration of insulin-like growth factor-1 in the range of 0.3 ng/ml to 3 ng/ml. In the second step the concentration of N-[2-OH-ethyl-]piperazine-N'-[2-ethane-sulfonic acid] is in the range of 14 mM to 22 mM, the concentration of sodium chloride is in the range of 90 mM to 140 mM, the concentration of calcium 2+ ion is in the range of 1.2 mM to 2.5 mM, the concentration of histidine is in the range of 1.0×10 -4 M to 2.5×10 -4 M, the concentration of isoleucine is in the range of 0.5×10 -4 M to 5.0×10 -4 M, the concentration of methionine is in the range of 1.0×10 -4 M to 5.0×10 -4 M, the concentration of phenylalanine is in the range of 1.0×10 -4 M to 5.0×10 -4 M, the concentration of tryptophan is in the range of 0.5×10 -4 M to 5.0×10 -4 M, the concentration of tyrosine is in the range of 1.0×10 -4 M to 5.0×10 -4 M, the concentration of hydrocortisone is in the range of 1.0×10 -7 M to 5.0×10 -7 M, the concentration of phosphoethanolamine is in the range of 0.7×10 -4 M to 1.5×10 -4 M, the concentration of ethanolamine is in the range of 0.7×10 -4 M to 1.5×10 -4 M, the concentration of epidermal growth factor is in the range of 1 ng/ml to 3 ng/ml, the concentration of insulin-like growth factor-1 is in the range of 0.3 ng/ml to 3 ng/ml, and the concentration of Beta-transforming growth factor is in the range of 15 ng/ml to 25 ng/ml. And in the third step the concentration of N-[2-OH-ethyl-]piperazine-N'-[2-ethane-sulfonic acid] is in the range of 14 mM to 22 mM, the concentration of sodium chloride is in the range of 90 mM to 140 mM, the concentration of calcium 2+ ion is in the range of 1.2 mM to 2.5 mM, the concentration of histidine is in the range of 1.0×10 -4 M to 2.5×10 -4 M, the concentration of isoleucine is in the range of 0.5×10 -4 M to 5.0×10 -4 M, the concentration of methionine is in the range of 1.0×10 -4 M to 5.0×10 -4 M, the concentration of phenylalanine is in the range of 1.0×10 -4 M to 5.0×10 -4 M, the concentration of tryptophan is in the range of 0.5×10 -4 M to 5.0×10 -4 M, and the concentration of tyrosine is in the range of 1.0×10 -4 M to 5.0× 10 -4 M, the concentration of linoleic acid is in the range of 7 microgram/ml to 12 microgram/ml, the concentration of hydrocortisone is in the range of 1.0×10 -7 M to 2.0×10 -7 M, the concentration of phosphoethanolamine is in the range of 0.7×10 -4 M to 1.5×10 -4 M, and the concentration of ethanolamine is in the range of 0.7×10 -4 M to 1.5×10 -4 M. The method for the formation of a histologically-complete skin substitute set forth above may include the use of modified concentrations of various components. In one such usage involving modified concentrations, in the first step the concentration of N-[2-OH-ethyl-]piperazine-N'-[2-ethane-sulfonic acid] is in the range of 14 mM to 22 mM, the concentration of sodium chloride is in the range of 90 mM to 140 mM, the concentration of calcium 2+ ion is approximately 0.125 mM, the concentration of histidine is in the range of 1.0×10 -4 M to 2.5×10 -4 M, the concentration of isoleucine is in the range of 0.5×10 -4 M to 5.0×10 -4 M, the concentration of methionine is in the range of 1.0×10 -4 M to 5.0×10 -4 M, the concentration of phenylalanine is in the range of 1.0×10 -4 M to 5.0×10 -4 M, the concentration of tryptophan is in the range of 0.5×10 -4 M to 5.0×10 -4 M, the concentration of tyrosine is in the range of 1.0×10 -4 M to 5.0×10 -4 M, the concentration of hydrocortisone is approximately 1.5×10 -7 M, the concentration of phosphoethanolamine is approximately 1.0×10 -4 M, the concentration of ethanolamine is approximately 1.0×10 - 4 M, the concentration of epidermal growth factor is approximately 1 ng/ml, and the concentration of insulin-line growth factor-1 is approximately 3 ng/ml, in the second step the concentration of N-[2-OH-ethyl-]piperazine-N'-[2-ethane-sulfonic acid] is in the range of 14 mM to 22 mM, the concentration of sodium chloride is in the range of 90 mM to 140 mM, the concentration of calcium 2+ ion is approximately 1.8 mM, the concentration of histidine is in the range of 1.0×10 -4 M to 2.5×10 -4 M, the concentration of isoleucine is in the range of 0.5×10 -4 M to 5.0×10 -4 M, the concentration of methionine is in the range of 1.0×10 -4 M to 5.0×10 -4 M, the concentration of phenylalanine is in the range of 1.0×10 -4 M to 5.0×10 -4 M, the concentration of tryptophan is in the range of 0.5×10 -4 M to 5.0×10 -4 M, the concentration of tyrosine is in the range of 1.0×10 -4 M to 5.0×10 -4 M, the concentration of hydrocortisone is approximately 1.5×10 -7 M, the concentration of phosphoethanolamine is approximately 1.0×10 -4 M, the concentration of ethanolamine is approximately 1.0×10 -4 M, the concentration of epidermal growth factor is approximately 1 ng/ml, the concentration of insulin-like growth factor-1 is approximately 0.3 ng/ml, and the concentration of Beta-transforming growth factor is approximately 20 ng/ml, and in the third step the concentration of N-[2-OH-ethyl-]piperazine-N'-[2-ethane-sulfonic acid] is in the range of 14 mM to 22 mM, the concentration of sodium chloride is in the range of 90 mM to 140 mM, the concentration of calcium 2+ ion is approximately 1.8 mM, the concentration of histidine is in the range of 1.0×10 -4 M to 2.5×10 -4 M, the concentration of isoleucine is in the range of 0.5×10 -4 M to 5.0×10 -4 M, the concentration of methionine is in the range of 1.0×10 -4 M to 5.0×10 -4 M, the concentration of phenylalanine is in the range of 1.0×10 -4 M to 5.0×10 -4 M, the concentration of tryptophan is in the range of 0.5×10 -4 M to 5.0×10 -4 M, and the concentration of tyrosine is in the range of 1.0×10 -4 M to 5.0×10 -4 M, the concentration of linoleic acid is approximately 10 microgram/ml, the concentration of hydrocortisone is approximately 2.0×10 -7 M, the concentration of phosphoethanolamine is approximately 1.0×10 -4 M, and the concentration of ethanolamine is approximately 1.0×10 -4 M. The method for the formation of a histologically-complete skin substitute set forth above may also include an additional step, namely the step of initially treating basal keratinocyte cells to increase clonal growth with a medium comprising N-[2-OH-ethyl-]piperazine-N'-[2-ethane-sulfonic acid] which is in a concentration in the range of 14 mM to 22 mM, sodium chloride which is in a concentration in the range of 90 mM to 140 mM, calcium 2+ ion which is in a concentration in the range of 0.03 mM to 0.3 mM, histidine which is in the concentration in the range of 1.0×10 -4 M to 2.5×10 -4 M, isoleucine which is in a concentration in the range of 0.5×10 -4 M to 5.0×10 -4 M, methionine which is in a concentration in the range of 1.0×10 -4 M to 5.0×10 -4 M, phenylalanine which is in a concentration in the range of 1.0×10 -4 M to 5.0×10 - 4 M, tryptophan which is in a concentration in the range of 0.5×10 -4 M to 5.0×10 -4 M, and tyrosine which is in a concentration in the range of 1.0×10 -4 M to 5.0×10 -4 M. If the additional step is used in the method for the formation of a histologically-complete skin substitute, the concentrations of the components may be modified such that the basal keratinocyte cells are initially treated with a medium in which concentration of N-[2-OH-ethyl-]piperazine-N'-[2-ethane-sulfonic acid] is in the range of 16 mM to 20 mM, the concentration of sodium chloride is in the range of 100 mM to 120 mM, the concentration of calcium 2+ ion is in the range of 0.05 mM to 0.15 mM, the concentration of histidine is in the range of 1.5×10 -4 M to 2.0×10 -4 M, the concentration of isoleucine is in the range of 1.5×10 -4 M to 3.0×10 -4 M, the concentration of methionine is in the range of 2.0×10 -4 M to 4.0×10 -4 M, the concentration of phenylalanine is in the range of 2.0×10 -4 M to 4.0×10 -4 M, the concentration of tryptophan is in the range of 1.5×10 -4 M to 2.5×10 -4 M, and the concentration of tyrosine is in the range of 2.0×10 -4 M to 4.0×10 -4 M. If the additional step is used in the method for the formation of a histologically-complete skin substitute, the concentrations of the components may be modified such that the basal keratinocyte cells are initially treated with a medium in the basal keratinocyte cells are initially treated with a medium in which concentration of N-[2-OH-ethyl-]piperazine-N'-[2-ethane-sulfonic acid] is approximately 20 mM, the concentration of sodium chloride is approximately 113 mM, the concentration of calcium 2+ ion is approximately 0.125 mM, the concentration of histidine is approximately 1.7×10 -4 M, the concentration of isoleucine is approximately 2.5×10 -4 M, the concentration of methionine is approximately 3.0×10 -4 M, the concentration of phenylalanine is approximately 3.0×10 -4 M, the concentration of tryptophan is approximately 2.0×10 -4 M, and the concentration of tyrosine is in the range of 3.0×10 -4 M. There is also disclosed a serum-free medium for use in the formation of a histologically-complete skin substitute comprising N-[2oh-ethyl-]piperazine-N'-[2-ethane-sulfonic acid], sodium chloride, calcium 2+ ion, histidine, isoleucine, methionine, phenylalanine, tryptophan, tyrosine, hydrocortisone, phosphoethanolamine, ethanolamine, epidermal growth factor, and insulin-like growth factor-1. In the above medium the concentration of N-[2-OH-ethyl-]piperazine-N'-[2-ethane-sulfonic acid] is in the range of 14 mM to 22 mM, the concentration of sodium chloride is in the range of 90 mM to 140 mM, the concentration of calcium 2+ ion is in the range of 0.03 mM to 0.3 mM, the concentration of histidine is in the range of 1.0×10 -4 M to 2.5×10 -4 M, the concentration of isoleucine is in the range of 0.5×10 -4 M to 5.0×10 -4 M, the concentration of methionine is in the range of 1.0×10 -4 M to 5.0×10 -4 M, the concentration of phenylalanine is in the range of 1.0×10 -4 M to 5.0×10 -4 M, the concentration of tryptophan is in the range of 0.5×10 -4 M to 5.0×10 -4 M, the concentration of tyrosine is in the range of 1.0×10 -4 M to 5.0×10 -4 M, the concentration of hydrocortisone is in the range of 1.0×10 -7 M to 5.0×10 -7 M, the concentration of phosphoethanolamine is in the range of 0.5×10 -4 M to 2.0×10 -4 M, the concentration of ethanolamine is in the range of 0.5×10 -4 M to 2.0×10 -4 M, the concentration of epidermal growth factor is in the range of 1 ng/ml to 25 ng/ml, and the concentration of insulin-like growth factor-1 is in the range of 0.3 ng/ml to 30 ng/ml. In a modified composition of the above medium, the concentration of N-[2-OH-ethyl-]piperazine-N'-[2-ethane-sulfonic acid] is in the range of 14 mM to 22 mM, the concentration of sodium chloride is in the range of 90 mM to 140 mM, the concentration of calcium 2+ ion is in the range of 0.1 mM to 0.15 mM, the concentration of histidine is in the range of 1.0×10 -4 M to 2.5×10 -4 M, the concentration of isoleucine is in the range of 0.5×10 -4 M to 5.0×10 -4 M, the concentration of methionine is in the range of 1.0×10 -4 M to 5.0×10 -4 M, the concentration of phenylalanine is in the range of 1.0×10 -4 M to 5.0×10 -4 M, the concentration of tryptophan is in the range of 0.5×10 -4 M to 5.0×10 -4 M, the concentration of tyrosine is in the range of 1.0×10 -4 M to 5.0×10 -4 M, the concentration of hydrocortisone is in the range of 1.0×10 -7 M to 2.0×10 -7 M, the concentration of phosphoethanolamine is in the range of 0.7×10 -4 M to 1.5×10 -4 M, the concentration of ethanolamine is in the range of 0.7×10 -4 M to 1.5×10 -4 M, the concentration of epidermal growth factor is in the range of 1 ng/ml to 5 ng/ml, and the concentration of insulin-like growth factor-1 is in the range of 0.3 ng/ml to 3 ng/ml. In yet another modified composition of the above medium the concentration of N-[2-OH-ethyl-]piperazine-N'-[2-ethane-sulfonic acid] is in the range of 14 mM to 22 mM, the concentration of sodium chloride is in the range of 90 mM to 140 mM, the concentration of calcium 2+ ion is approximately 0.125 mM, the concentration of histidine is in the range of 1.0×10 -4 M to 2.5×10 -4 M, the concentration of isoleucine is in the range of 0.5×10 -4 M to 5.0×10 -4 M, the concentration of methionine is in the range of 1.0×10 -4 M to 5.0×10 -4 M, the concentration of phenylalanine is in the range of 1.0×10 -4 M to 5.0×10 -4 M, the concentration of tryptophan is in the range of 0.5×10 -4 M to 5.0×10 -4 M, the concentration of tyrosine is in the range of 1.0×10 -4 M to 5.0× 10 -4 M, the concentration of hydrocortisone is approximately 1.5×10 -7 M, the concentration of phosphoethanolamine is approximately 1.0×10 -4 M, the concentration of ethanolamine is approximately 1.0×10 -4 M, the concentration of epidermal growth factor is approximately 1 ng/ml, and the concentration of insulin-like growth factor-1 is approximately 3 ng/ml. There is also disclosed a serum-free medium for use in the formation of a histologically-complete skin substitute comprising N-[2-OH-ethyl-]piperazine-N'-[2-ethane-sulfonic acid], sodium chloride, calcium 2+ ion, histidine, isoleucine, methionine, phenylalanine, tryptophan, tyrosine, hydrocortisone, phosphoethanolamine, ethanolamine, epidermal growth factor, insulin-like growth factor-1, and Beta-transforming growth factor. In the above medium the concentration of N-[2-OH-ethyl-]piperazine-N'-[2-ethane-sulfonic acid] is in the range of 14 mM to 22 mM, the concentration of sodium chloride is in the range of 90 mM to 140 mM, the concentration of calcium 2+ ion is in the range of 0.7 mM to 3.0 mM, the concentration of histidine is in the range of 1.0×10 -4 M to 2.5×10 -4 M, the concentration of isoleucine is in the range of 0.5×10 -4 M to 5.0×10 -4 M, the concentration of methionine is in the range of 1.0×10 -4 M to 5.0×10 -4 M, the concentration of phenylalanine is in the range of 1.0×10 -4 M to 5.0×10 -4 M, the concentration of tryptophan is in the range of 0.5×10 -4 M to 5.0×10 -4 M, the concentration of tyrosine is in the range of 1.0×10 -4 M to 5.0×10 -4 M, the concentration of hydrocortisone is in the range of 1.0×10 -7 M to 10.0×10 -7 M, the concentration of phosphoethanolamine is in the range of 0.5×10 -4 M to 2.0×10 -4 M, the concentration of ethanolamine is in the range of 0.5×10 -4 M to 2.0×10 -4 M, the concentration of epidermal growth factor is in the range of 1 ng/ml to 5 ng/ml, the concentration of insulin-like growth factor-1 is in the range of 0.3 ng/ml to 30 ng/ml, and the concentration of Beta-transforming growth factor is in the range of 3.0 ng/ml to 30 ng/ml. In a modified composition of the above medium, the concentration of N-[2-OH-ethyl-]piperazine-N'-[2-ethane-sulfonic acid] is in the range of 14 mM to 22 mM, the concentration of sodium chloride is in the range of 90 mM to 140 mM, the concentration of calcium 2+ ion is in the range of 1.2 mM to 2.5 mM, the concentration of histidine is in the range of 1.0×10 -4 M to 2.5×10 -4 M, the concentration of isoleucine is in the range of 0.5×10 -4 M to 5.0×10 -4 M, the concentration of methionine is in the range of 1.0×10 -4 M to 5.0×10 -4 M, the concentration of phenylalanine is in the range of 1.0×10 -4 M to 5.0×10 -4 M, the concentration of tryptophan is in the range of 0.5×10 -4 M to 5.0×10 -4 M, the concentration of tyrosine is in the range of 1.0×10 -4 M to 5.0×10 -4 M, the concentration of hydrocortisone is in the range of 1.0×10 -7 M to 5.0×10 -7 M, the concentration of phosphoethanolamine is in the range of 0.7×10 -4 M to 1.5×10 -4 M, the concentration of ethanolamine is in the range of 0.7×10 -4 M to 1.5×10 -4 M, the concentration of epidermal growth factor is in the range of 1 ng/ml to 3 ng/ml, the concentration of insulin-like growth factor-1 is in the range of 0.3 ng/ml to 3 ng/ml, and the concentration of Beta-transforming growth factor is in the range of 15 ng/ml to 25 ng/ml. In yet another modified composition of the above medium the concentration of N-[2-OH-ethyl-]piperazine-N'-[2-ethane-sulfonic acid] is in the range of 14 mM to 22 mM, the concentration of sodium chloride is in the range of 90 mM to 140 mM, the concentration of calcium 2+ ion is approximately 1.8 mM, the concentration of histidine is in the range of 1.0×10 -4 M to 2.5×10 -4 M, the concentration of isoleucine is in the range of 0.5×10 -4 M to 5.0×10 -4 M, the concentration of methionine is in the range of 1.0×10 -4 M to 5.0×10 -4 M, the concentration of phenylalanine is in the range of 1.0×10 -4 M to 5.0×10 -4 M, the concentration of tryptophan is in the range of 0.5×10 -4 M to 5.0×10 -4 M, the concentration of tyrosine is in the range of 1.0×10 -4 M to 5.0× 10 -4 M, the concentration of hydrocortisone is approximately 1.5×10 -7 M, the concentration of phosphoethanolamine is approximately 1.0×10 -4 M, the concentration of ethanolamine is approximately 1.0×10 -4 M, the concentration of epidermal growth factor is approximately 1 ng/ml, the concentration of insulin-like growth factor-1 is approximately 0.3 ng/ml, and the concentration of Beta-transforming growth factor is approximately 20 ng/ml. There is also disclosed a serum-free medium for use in the formation of a histologically-complete skin substitute comprising N-[2-OH-ethyl-]piperazine-N'-[2-ethane-sulfonic acid], sodium chloride, calcium 2+ ion, histidine, isoleucine, methionine, phenylalanine, tryptophan, tyrosine, linoleic acid, hydrocortisone, phosphoethanolamine, and ethanolamine. In the above medium the concentration of N-[2-OH-ethyl-]piperazine-N'-[2-ethane-sulfonic acid] is in the range of 14 mM to 22 mM, the concentration of sodium chloride is in the range of 90 mM to 140 mM, the concentration of calcium 2+ ion is in the range of 0.7 mM to 3.0 mM, the concentration of histidine is in the range of 1.0×10 -4 M to 2.5×10 -4 M, the concentration of isoleucine is in the range of 0.5×10 -4 M to 5.0×10 -4 M, the concentration of methionine is in the range of 1.0×10 -4 M to 5.0×10 -4 M, the concentration of phenylalanine is in the range of 1.0×10 -4 M to 5.0×10 -4 M, the concentration of tryptophan is in the range of 0.5×10 -4 M to 5.0×10 -4 M, the concentration of tyrosine is in the range of 1.0×10 -4 M to 5.0×10 -4 M, the concentration of linoleic acid is in the range of 1 microgram/ml to 15 microgram/ml, the concentration of hydrocortisone is in the range of 1.0×10 -7 M to 10.0×10 -7 M, the concentration of phosphoethanolamine is in the range of 0.5×10 -4 M to 2.0×10 -4 M, and the concentration of ethanolamine is in the range of 0.5×10 -4 M to 2.0×10 -4 M. In a modified composition of the above medium, the concentration of N-[2-OH-ethyl-]piperazine-N'-[2-ethane-sulfonic acid] is in the range of 14 mM to 22 mM, the concentration of sodium chloride is in the range of 90 mM to 140 mM, the concentration of calcium 2+ ion is in the range of 1.2 mM to 2.5 mM, the concentration of histidine is in the range of 1.0×10 -4 M to 2.5×10 -4 M, the concentration of isoleucine is in the range of 0.5×10 -4 M to 5.0×10 -4 M, the concentration of methionine is in the range of 1.0×10 -4 M to 5.0×10 -4 M, the concentration of phenylalanine is in the range of 1.0×10 -4 M to 5.0×10 -4 M, the concentration of tryptophan is in the range of 0.5×10 -4 M to 5.0×10 -4 M, and the concentration of tyrosine is in the range of 1.0×10 -4 M to 5.0×10 -4 M, the concentration of gamma-linoleic acid is in the range of 7 microgram/ml to 12 microgram/ml, the concentration of hydrocortisone is in the range of 1.0×10 -7 M to 2.0×10 -7 M, the concentration of phosphoethanolamine is in the range of 0.7×10 -4 M to 1.5×10 -4 M, and the concentration of ethanolamine is in the range of 0.7×10 -4 M to 1.5×10 -4 M. In yet another modified composition of the above medium the concentration of N-[2-OH-ethyl-]piperazine-N'-[2-ethane-sulfonic acid] is in the range of 14 mM to 22 mM, the concentration of sodium chloride is in the range of 90 mM to 140 mM, the concentration of calcium 2+ ion is approximately 1.8 mM, the concentration of histidine is in the range of 1.0×10 -4 M to 2.5×10 -4 M, the concentration of isoleucine is in the range of 0.5×10 -4 M to 5.0×10 -4 M, the concentration of methionine is in the range of 1.0×10 -4 M to 5.0×10 -4 M, the concentration of phenylalanine is in the range of 1.0×10 -4 M to 5.0×10 -4 M, the concentration of tryptophan is in the range of 0.5×10 -4 M to 5.0×10 -4 M, and the concentration of tyrosine is in the range of 1.0×10 -4 M to 5.0×10 -4 M, the concentration of linoleic acid is approximately 10 microgram/ml, the concentration of hydrocortisone is approximately 2.0×10 -7 M, the concentration of phosphoethanolamine is approximately 1.0×10 -4 M, and the concentration of ethanolamine is approximately 1.0×10 -4 M. There is also disclosed a serum-free medium for use in the formation of a histologically-complete skin substitute comprising N-[2-OH-ethyl]piperazine-N'-[2-ethane-sulfonic acid], sodium chloride, calcium 2+ ion, histidine, isoleucine, methionine, phenylalanine, tryptophan, and tyrosine. In the above medium the concentration of N-[2-OH-ethyl-]piperazine-N'-[2-ethane-sulfonic acid] is in the range of 14 mM to 22 mM, the concentration of sodium chloride is in the range of 90 mM to 140 mM, the concentration of calcium 2+ ion is in the range of 0.03 mM to 0.3 mM, the concentration of histidine is in the range of 1.0×10 -4 M to 2.5×10 -4 M, the concentration of isoleucine is in the range of 0.5×10 -4 M to 5.0×10 -4 M, the concentration of methionine is in the range of 1.0×10 -4 M to 5.0×10 -4 M, the concentration of phenylalanine is in the range of 1.0×10 -4 M to 5.0×10 -4 M, the concentration of tryptophan is in the range of 0.5×10 -4 M to 5.0×10 -4 M, and the concentration of tyrosine is in the range of 1.0×10 -4 M to 5.0×10 -4 M. In a modified composition of the above medium, the concentration of N-[2-OH-ethyl-]piperazine-N'-[2-ethane-sulfonic acid] is in the range of 16 mM to 20 mM, the concentration of sodium chloride is in the range of 100 mM to 120 mM, the concentration of calcium 2+ ion is in the range of 0.05 mM to 0.15 mM, the concentration of histidine is in the range of 1.5×10 -4 M to 2.0×10 -4 M, the concentration of isoleucine is in the range of 1.5×10 -4 M to 3.0×10 -4 M, the concentration of methionine is in the range of 2.0×10 -4 M to 4.0×10 -4 M, the concentration of phenylalanine is in the range of 2.0×10 -4 M to 4.0×10 -4 M, the concentration of tryptophan is in the range of 1.5×10 -4 M to 2.5×10 =31 4 M, and the concentration of tyrosine is in the range of 2.0×10 -4 M to 4.0×10 -4 M. In yet another modified composition of the above medium the concentration of N-[2-OH-ethyl-]piperazine-N'-[2-ethane-sulfonic acid] is approximately 20 mM, the concentration of sodium chloride is approximately 113 mM, the concentration of calcium 2+ ion is approximately 0.125 mM, the concentration of histidine is approximately 1.7×10 -4 M, the concentration of isoleucine is approximately 2.5×10 -4 M, the concentration of methionine is approximately 3.0×10 -4 M, the concentration of phenylalanine is approximately 3.0×10 -4 M, the concentration of tryptophan is approximately 2.0×10 -4 M, and the concentration of tyrosine is in the range of 3.0×10 -4 M. EXAMPLE 5 Applications of Reformed Human Epidermis as a Living Skin substitute. From previous studies in the literature it is widely known that human skin is a target organ for certain sex steroid hormones. In fact, skin is the next most active site after the liver for the metabolic interconversions of steroid hormones. Nevertheless, little is known about the direct effect of sex steroid hormones such as testosterone, progesterone and estrogens on the growth and differentiation of normal human keratinocytes. A. Effect of sex steroid hormones on basal epidermal cells cultured in serum-free medium. It has been reported (Peehl, D. M. and Ham, R. G., In Vitro 16:516-525 (1980)] that 17-β-estradiol stimulated the growth of epidermal cells in culture. However, the stimulatory effect that was observed was minimal and occurred under less than optimal clonal growth conditions. To whit, the medium employed and the growth factors present in that medium were not the media in which serum-free growth occurs under completely defined conditions. In view of these considerations, and because living skin substitutes are an ideal model for assaying the effects of sex steroid hormones it was important to reassess the effects of sex steroid hormones in HECK-109 medium containing only defined components and supplements. This example (5A) details my findings of the effect of testosterone, progesterone, 17-β-estradiol on the clonal growth of normal human keratinocytes in HECK-109FS. Table V present results which show that both progesterone (3.7×10 -6 M) and 17-β-estradiol (3.4×10 -6 M) exert an inhibitory action on the proliferation of basal keratinocyte stem cells derived from either newborn foreskin or adult breast skin. By contrast, testosterone (3.7×10 -6 M) has only a negligible effect on the clonal growth of these cells. Further, the results show that female-derived keratinocytes are less sensitive to the inhibitory effect of the TABLE V______________________________________Effect of Estradiol, Progesterone, and Testosteroneon Clonal Growth of Normal Human Basal Keratinocytes Growth Responses.sup.a (colonies/dish)Culture conditions AH.sup.b NF.sup.c______________________________________HECK-109FS medium 569 286 585 312+ Testosterone 603 259(1.0 μg/ml) 583 264+ Progesterone 311 58(1.0 μg/ml) 402 26+ Estradiol 426 83(1.0 μg/ml) 363 58______________________________________ .sup.a Values represent the results of duplicate determinations. .sup.b AH, adult skin keratinocytes were seeded at a density of 1000 cell per dish; the dishes were fixed and counted 10 days later. .sup.c NF, foreskin keratinocytes were seeded at a density of 500 cells per dish; the dishes were fixed and counted 10 days later. female sex steroid hormones than are the male-derived keratinocytes (provided that the keratinocytes derived from adult skin are also for some unknown reason less sensitive than newborn). The above following removal from the culture preferably by any of the common, well-known ways that recovery is done, such as by treatment with a protease, results imply that the normal pathways regulating keratinocyte proliferation may be profoundly perturbed by continuous exposure to progesterone or progesterone-related steroids, and therefore, these effects may need to be taken into account where reformed human epidermis is used as a model for the transdermal delivery of contraceptive steroids. B. Demonstration of specific and saturable 17-β-estradiol receptors in reformed human epidermis. Human epidermis reformed in serum-free culture by the process steps outlined above can be used as a model system to assay the affect of a wide variety of test substances, e.g., hormones, toxins, viruses and carcinogens. Of immediate interest for the use of reformed human epidermis as a living skin substitute for transdermal delivery of contraceptive hormones is the question of whether reformed human epidermis has specific and saturable sex steroid hormone binding sites. This example (5B) presents a series of experiments to measure the binding of radiolabelled 17-β-estradiol to replicate samples of human epidermis from a single genetic source. Reformed human epidermis was produced by culturing basal keratinocytes as outlined in Example 2 in replicate 24-well cluster dishes (Corning Tissue Culture Wares, Corning, N.Y.) through Phase III of culture. Several test wells were sampled at the time of the binding experiments by standard histological methods to verify that a complete epidermis had, indeed, been produced. The conditions of the binding assay were as follows: Phase III culture medium was aseptically removed and to the reformed human epidermis in each well 0.5 ml of CCS containing 10 to 50 nmol of radiolabelled 17-beta-estradiol (160 Ci/mM;0.2 μCi/ml) was added. The radiolabelled estradiol was purchased from New England Nuclear Corporation, Boston, Mass. The concentration of radiolabelled estradiol was fixed at half maximal saturation to assure effective competition with unlabelled identical and analogue steroid hormones over a wide range of competitor concentrations. The sex steroid competitors tested in the competition binding assay were 17-β-estradiol and other analogues such as testosterone, estriol, levonorgestral and norethisterone. At the end of the 20 hour incubation interval (at 40° C.) the radiolabelled solutions were removed, the surface of the reformed human epidermis samples rinsed gently with 1 ml of ice-cold CCS and 0.5 ml of Type IV collagenase (Dispase, 20 U/ml, Boehringer-Manheim, Los Angeles, Calif.) added to each well to enzymatically release the intact epidermal sheet. The released reformed human epidermis [SEE: FIG. 5] from each treatment well was transferred to its respective vial and the contained radioactivity was counted in a scintillation spectrometer. As shown in FIG. 6, only 17-β-estradiol was an efficient competitor for the 17-β-estradiol receptor. Estriol, a close structural analog of estradiol also showed significant competition while testosterone and the progesterone analogues were not competitive. These results demonstrate that reformed human epidermis produced as intact epidermal sheets is a good model for biochemical assay of steroid sex hormone receptors and the results also provide direct evidence for the functional fidelity of reformed human epidermis as a living skin substitute. INDUSTRIAL AND CLINICAL APPLICABILITY The following claims are based on the five disclosures presented above in Examples 1 through 5. They include the design and formulation of the novel HECK 109 mediums which have been 5 differently supplemented to provide for the serial achievement of the three-step cellular differentiation process of pluripotent basal cell keratinocytes to a fully differentiated human skin in vitro: i] HECK-109, the basal medium for cell starting; ii] HECK-109-fully supplemented (hereinafter referred to as HECK-109FS) for 10 control over cellular growth; iii] HECK-109-differentiation medium (hereinafter referred to HECK-109DM) for the induction of differentiation and formation of a malphigian layer (SEE: FIG. 1A+B); and iv] HECK-109-cornification medium (hereinafter referred to HECK-109CM) designed for the induction of cellular differentiation of a stratum lucidum, stratum corneum, and stratum disjunction in a preexisting reformed epidermis produced by HECK-DM. The fifth and sixth claims involve the process for the sequential rendering of the culture process steps and the method of sequential control in the in vitro construction of a histologically-complete living skin substitute. These media and processes have application in in vitro testing of pharmaceuticals and topical drugs; screening of toxicants, carcinogens, complete or incomplete tumor promoters; evaluation of infective human agents including viruses, e.g. human papilloma viruses, Herpes-simplex viruses and Epstein-Barr virus; screening of cosmetics; production of keratinocyte products including protease inhibitors, growth factors, wound-healing factors, e.g. α-, β-TGF and α-EGF, low-density lipoprotein receptors, laminins, fibronectins, retinoid receptors and binding proteins, steroid hormone receptors, transglutaminases, and cross-linking proteins of the cornified envelope; products for the abolition and/or prevention of wrinkles or screening of agents with potential for prevention of wrinkles; products for use in the introduction of immunizing agents into the recipient a reformed human epidermis graft or evaluation of cross-typing of donor-recipient tissues; and the use of autologously-derived cells for transplantation in the treatment of burns or other trauma.

Methods and formulations are disclosed for the in vitro formation of a histologically complete human epidermis in a serum-free, companion cell or cell feeder layer-free, and organotypic matrix-free culture system commencing with the isolation and cultivation of a unique population of clonally-competent basal epidermal cells and ending with the formation of a functional, histologically complete, human squamous epithelium. The formation of a histologically complete human epidermis is accomplished in a serum-free medium, without companion-cells or feeder layer cells or any organotypic support using a multi-step process that is controlled by manipulating the growth and differentiation factors requisite to the sequential development of a usable, functional, and completely differentiated epidermis. The entire culture process can be accomplished in a relatively short time (3 to 4 weeks) with complete reproducibility and can supply copious amounts (2 to 3 square meters) of viable reformed human epidermis for a variety of experimental, clinical and commercial purposes where a histologically-complete living skin substitute is required.

STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT Not applicable. CROSS REFERENCE TO RELATED APPLICATIONS Not applicable. REFERENCE TO MICROFICHE APPENDIX Not applicable. CROSS REFERENCE TO RELATED APPLICATIONS Not applicable. REFERENCE TO MICROFICHE APPENDIX Not applicable. BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to the field of bakery cutting devices in general, and in particular to multiple segment bakery cutting devices in particular. 2. Description of Related Art As can be seen by reference to the following U.S. Pat. Nos. 4,250,618; 4,625,404; 5,074,777; and 5,129,159, the prior art is replete with myriad and diverse bakery cutting and/or segmenting devices used to produce uniform size bakery goods. While all of the aforementioned prior art constructions are more than adequate for the basic purpose and function for which they have been specifically designed, they are uniformly deficient with respect to their failure to provide a simple, efficient, and practical way to make a bakery style grid device that will produce a plurality of bakery goods of uniform size and cleanly defined edges. As anyone who has employed the prior art grid devices is all too well aware, the removal of the individual bakery goods from within the individual grid pattern openings is often a cumbersome and messy chore producing less than aesthetically pleasing results. As a consequence of the foregoing situation, there has existed a longstanding need for a new and improved type of bakery grid device that will forcibly separate the bakery goods from the sides of the grid pattern to produce uniform edged bakery goods and the provision of such a construction is a stated objective of the present invention. BRIEF SUMMARY OF THE INVENTION Briefly stated, the impact actuated bakery grid device that forms the basis of the present invention comprises a grid unit provided with a handle unit that is operatively associated with a force generating unit for imparting a controlled impact force to the grid unit. As will be explained in greater detail further on in the specification, the handle unit includes a handle member connected at spaced locations on the grid unit. The force generating unit is centrally disposed on the handle member. In addition, the force generating unit includes a spring biased rod member slideably disposed within a housing element attached to the handle element. The rod member may be retracted against a spring element and then released such that the bottom of the rod member forms an impact surface that is brought into forcible contact with the handle member which transmits the impact force to the grid unit. BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS These and other attributes of the invention will become more clear upon a thorough study of the following description of the best mode for carrying out the invention, particularly when reviewed in conjunction with the drawings, wherein: FIG. 1 is a perspective view of the impact actuated bakery grid device that forms the basis of the present invention; FIG. 2 is a cross-sectional view of the device taken through line 2--2 of FIG. 1; and FIG. 3 is an isolated partial cut-away view of the force transmitting unit of the invention. DETAILED DESCRIPTION OF THE INVENTION As can be seen by reference to the drawings, and in particularly to FIG. 1, the impact actuated bakery grid device that forms the basis of the present invention is designated generally by the reference number 10. The grid device 10 comprises in general a grid unit 11, a handle unit 12, and a force transmitting unit 13. These units will now be described in seriatim fashion. As can be seen by reference to FIGS. 1 and 2, the grid unit 11 comprises a grid member 20 including a plurality of perpendicularly aligned longitudinal 21 and transverse 22 rows of blade elements 23 that are arranged in a grid pattern to define a plurality of identically configured internal compartments 24 and a plurality of identically configured external peripheral panel segments 25 which cooperate with a suitably configured baking pan or the like (not shown) to define similarly configured peripheral compartments 26. In the preferred embodiment of the invention illustrated in the drawings, the blade elements 23 may be fabricated from stainless steel or Teflon® depending upon whether the grid member 20 is to be primarily employed as a cutting tool after the bakery item has been cooked, or is to be used primarily to segregate the bakery item into individual serving portions during the cooking process. Still referring to FIGS. 1 and 2, it can be seen that the handle unit 12 comprises a generally inverted U-shaped handle member 30 having a pair of widely spaced downwardly depending arms 31 which are connected along the longitudinal axis of the grid member 20 for reasons that will be explained presently. Turning now to FIGS. 2 and 3, it can be seen that the force transmitting unit 13 comprises in general, an elongated force transmitting rod member 40 having an enlarged knob element 41 disposed on its upper end. The lower end of the rod member 40 is slideably received in a hollow cylindrical housing element 42 which is centrally disposed on the handle member 30. In addition, the lower end of the rod member 40 is operatively attached to a spring 43 which is captively received within the housing element 42 such that the rod member 40 may be retracted relative to the housing element 42 against the downward biasing force of the spring 43. Then once the knob element 41 is released, the bottom 45 of the rod member 40 will forcibly impact the handle member 30 which will transfer the impact force to the perpendicular rows 21, 22 of blades 23 to forcibly separate the blade surfaces 23 from contact with any adhering portion of the baked goods surrounded by the blade surfaces 23. As can also be seen by reference to FIGS. 2 and 3, the housing element 42 is further provided with a latching element 44 which will releasably engage the spring element 43 to immobilize the rod member 40 relative to the housing element 42 when the rod member 40 is not being used in its force transmitting mode. This arrangement allows the force transmitting unit 13 to act as an extension of the handle unit 12 when not being employed for its primary purpose. As was previously mentioned, the grid device 10 may be used either subsequent to, or during the baking process. In either event, the force generating unit 13 will forcibly dislodge with the assistance of gravity, any baked goods clinging to the interior surfaces of both the interior compartments 24 and the opposed surfaces of the peripheral compartments 26. This procedure can be accomplished without the need to apply downward pressure on the top surface of the individual serving portions of baked goods that would otherwise be frictionally engaged within the compartments 24 or 26. In addition, the generally uniform impact force generated by the force generating unit 13 should also result in a clean disengagement of the individual serving portions from each of the compartments 24, 26, such that the serving and/or segregation of the baked goods will produce individual portions of a uniform size and appearance with virtually no particles of foodstuffs clinging to the surfaces of the rows 21 and 22 of blade elements 23. It should also be noted that when the grid device 10 is in use, the user has the option to selectively disable the force generating unit 13 by use of the latching element 44. When the latching element 44 is engaged, the enlarged knob 41 on the rod member 40 may be used as an extension of the handle member 30 to produce a downwardly directed force on the grid member 20. When the latching element 44 is not operatively engaged, the user can grasp the handle member 30 on opposite sides of the housing element 42 to produce a downwardly directed force on the grid member 20. Furthermore, the widely spaced contact of the arms 31 of the handle member 30 will insure that the force imparted to the handle member 30 by the force generating unit 13 will be uniformly distributed to the grid member 20. Although only an exemplary embodiment of the invention has been described in detail above, those skilled in the art will readily appreciate that many modifications are possible without materially departing from the novel teachings and advantages of this invention. Accordingly, all such modifications are intended to be included within the scope of this invention as defined in the following claims. In the claims, means-plus-function clauses are intended to cover the structures described herein as performing the recited function and not only structural equivalents, but also equivalent structures. Thus, although a nail and a screw may not be structural equivalents in that a nail employs a cylindrical surface to secure wooded parts together, whereas, a screw employs a helical surface, in the environment of fastening wooden parts, a nail and a screw may be equivalent structures.

An impact actuated bakery grid device 10 for producing uniform portions of baked goods wherein the grid device 10 includes a force generating unit 13 operatively associated with a handle member 30 which is connected at widely spaced locations on a grid member 20 for forcibly ejecting the portions of baked goods from within the confines of a plurality of compartments 24 within the grid member 20.

CROSS-REFERENCE TO RELATED APPLICATION The present application is a division of application Ser. No. 07/848,517, filed Mar. 9, 1992, now abandoned, which was a division of application Ser. No. 07/371,249, filed Jun. 26, 1989, now U.S. Pat. No. 5,114,844, which, in turn, was a continuation-in-part application of Ser. No. 07/322,864, filed Mar. 24, 1989, now abandoned, the entire contents of which are hereby incorporated by reference. FIELD OF THE INVENTION The present invention relates to a method for detecting the existence of, a tendency to develop, or the initiation of a process leading to insulin dependent diabetes mellitus (IDDM), and, more particularly, to such a method which detects the presence of a 65 KD heat shock protein (hsp65) or antibodies to this protein. The present invention further relates to a method for the prevention of IDDM or the treatment of IDDM in its incipient stages by administering hsp65 in such a manner as to cause immunological tolerance therefor. BACKGROUND OF THE INVENTION Insulin dependent diabetes mellitus (IDDM) is caused by an autoimmune process which destroys the insulin-producing beta cells. Diabetes becomes clinically evident only after the vast majority of beta cells are irrevocably destroyed (perhaps 90%) and the life of the individual becomes dependent on an exogenous supply of insulin. In other words, at the time of clinical diagnosis, the autoimmune process has already done irreversible damage, most of it without noticeable symptoms. Successful treatment of the autoimmune process responsible for the disease ideally should be initiated before the patient has overt symptoms of diabetes and requires insulin replacement for his or her own lost capability to produce insulin. Termination of the autoimmune process would result in cure of the disease and prevention of the need for exogenous insulin only if the disease process could be halted while the patient still possessed a sufficient number of beta cells to provide adequate amounts of endogenous insulin. Therefore, any form of therapy would be more effective if persons at risk could be identified while they were yet without overt symptoms of IDDM and before the patients require exogenous insulin. About 90% of new cases of IDDM occur outside of families with known cases. Therefore, assays suitable for mass screening are urgently needed to detect the subclinical disease process at a stage before it is irreversible. Fortunately, there are a variety of animal models for IDDM, including BB rats and NOD mice (for example, see Rossini et al., Ann. Rev. Immunol., 3:289-320, 1985). Many of the animals develop autoimmune IDDM spontaneously, and demonstrate many of the features of IDDM in humans. Heat shock proteins (hsp's) are a family of proteins produced by cells exposed to elevated temperatures or other stresses. The hsp's include proteins of various molecular weights, including 20KD, 65-68KD, 70 KD, 90 KD, 110 KD, and others. The heat shock proteins are ubiquitous throughout nature; they are produced by bacteria, yeasts, plants, insects, and higher animals, including humans. The hsp protein molecules are highly conserved and show remarkable homology between all of these diverse creatures. Because of their extreme conservation over evolutionary time, heat shock proteins are thought to perform vital functions. They usually exhibit increased synthesis following exposure of cells to stressful stimuli including heat, certain metals, drugs, or amino acid analogues. Nevertheless, the special functions of these proteins so far are obscure. For example, patients with systemic lupus erythematosus (SLE) were observed to have antibodies to a 90 KD heat shock protein (Minota et el., J. Clin. Invest., 81:106-109, 1988). The function of these antibodies to hsp90 are not known. Hsp65 was found to be involved in adjuvant arthritis in rats, cf. van Eden et al., Nature, 331:171-173, 1988. Adjuvant arthritis is an autoimmune arthritis triggered by immunizing certain strains of rats to Mycobacterium tuberculosis (MT) organisms. It was found that the disease could be transferred to immunologically naive, irradiated rats by a clone of T-lymphocytes reactive to a 9 amino acid peptide sequence (180-188) of the hsp65 of MT. Thus, adjuvant arthritis appeared to be an autoimmune disease produced by anti-hsp65 T-lymphocytes. The autoimmune attack against the Joints was attributed to partial sequence homology between the 180-185 hsp65 peptide and a segment of the link protein of the cartilage proteoglycan (cf. Cohen, Scientific American, 258:52-60, 1988). It was also found that T-lymphocytes from the synovial fluids of patients with rheumatoid arthritis responded to the hsp65 of MT (cf. Res et al., Lancet, II:478-480, (1988). Administration of hsp65 to rats before induction of adjuvant arthritis was found to prevent the later development of arthritis. Thus, the presence of an immune response to hsp65 was associated with arthritis in both rats and humans, and administration of hsp65 could lead to resistance to arthritis. European patent application 262,710 discloses polypeptides useful for alleviation, treatment, and diagnosis of autoimmune arthritis and similar autoimmune diseases. The complete primary structure, including nucleotide and deduced amino acid sequence of the human P1 protein has recently been published in Jindal, S. et al, "Primary Structure of a Human Mitochondrial Protein Homologous to the Bacterial and Plant Chaperonins and to the 65-Kilodalton Mycobacterial Antigen," Molecular and Cellular Biology, 9, 5, 2279-2283, 1989. This protein, disclosed as having a molecular weight of about 63 kDa, is the human heat shock protein referred to herein as the hHSP65 protein. The entire contents of this publication are hereby incorporated herein by reference. SUMMARY OF THE INVENTION It is an object of the present invention to provide a method of early diagnosis of insulin dependent diabetes mellitus (IDDM). It is a further object of the present invention to provide kits for use in the early diagnosis of IDDM. It is another object of the present invention to provide a method for the prevention of IDDM. It is yet another object of the present invention to provide a method for the treatment of IDDM in its incipient stages. It is still a further object of the present invention to provide a tolerogenic composition for the prevention or treatment of IDDM. According to the discovery of the present invention, in the course of developing IDDM, animals express hsp65 molecules which find their way into the blood and urine of the animals. They also express antibodies to the hsp65 molecule. Thus, the presence of hsp65 or antibodies to hsp65 in blood or urine serves as an assay for the detection of the IDDM process before the destruction of beta cells is completed and the individual is doomed to life-long diabetes. The presence or incipience of IDDM in a patient can be diagnosed by testing for the presence of hsp65 or antibodies to hsp65. The present invention also relates to means for performing such assays, as well as kits for performing such assays. The detection of incipient diabetes then permits a patient to begin measures aimed at terminating the autoimmune process. For example, the administration of hsp65 is effective in inducing resistance to the autoimmune process involved in IDDM. The present invention further relates to means for preventing or treating IDDM. It has been discovered that immunization to hsp65 in an appropriate adjuvant can induce IDDM. However, vaccination with hsp65 without an effective adjuvant, and preferably with a tolerogenic carrier, can produce a specific tolerance to the antigen. This effectively creates a resistance to the autoimmune process of IDDM. If the patient is shown to already be in the pre-clinical incipient stages of IDDM, injection with such an antigen can create a tolerance for this antigen and thus arrest the autoimmune process before significant, permanent damage is done. BRIEF DESCRIPTION OF THE DRAWINGS The present invention will be better understood from the following brief description of the drawings and the subsequent detailed description of the preferred embodiments. FIG. 1 shows the amounts of hsp65, anti-hsp65, anti-insulin antibody, and anti-idiotypic antibody in the serum of NOD mice that did not develop IDDM. FIG. 2 is a graph showing that marked increases in hsp65 and anti-hsp65 precede the development of overt IDDM in NOD mice that did develop the disease. Anti-insulin and idiotypic (DM) antibodies preceded IDDM by a lesser extent. FIG. 3A-B shows the nucleotide and deduced amino acid sequences of the human P1 protein, which is an hHSP65. Numbers on the left refer to the nucleotide sequence relative to coordinate 1 at the beginning of the putative initiation codon. The amino acid sequence is numbered starting with 1 at the same point. The 5' extension of this reading frame is shown in one-letter code. The position of the internal EcoRI site (nt 712), which marks the beginning of the λ22a sequence, is indicated. The polyadenylation signal 15 nt from the A tail at the 3' end is underlined. The putative mitochondrial targeting sequence at the N-terminal end and a keratinlike amino acid sequence at the C-terminal end containing repeats of Gly-Gly-Met are boxed. Positively charged amino acids in the leader sequence are identified (+). DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS The particular protein produced by the human body during development of IDDM, which serves as a diagnostic marker in accordance with the present invention for the incipient outbreak of IDDM, is the human heat shock protein having a size of about 65 KD. The nucleotide and deduced amino acid sequence of this protein are set forth in FIG. 3A-B. This protein will hereinafter be referred to as hHSP65. It has been discovered, however, that other proteins may also be present which cross-react to the same antibodies which bind the 65 KD protein. For example, in mice and rats, 47 KD, 30 KD and 25 KD molecules were found which also cross-react with a monoclonal antibody specific to the hsp65 molecule of M. tuberculosis. A 47 KD molecule has also been discovered in rat fibroblasts which is cross-reactive with such an antibody. In view of the cross-species preservation of heat shock protein, it is fully expected that these will also be present in humans. Accordingly, for the purpose of the present specification and claims, the term "hHSP65" is intended to comprehend not only the 65 KD human heat shock protein, but also any other related molecule found in the human serum which cross-reacts with polyclonal antibodies raised against a 65 KD heat shock protein of any species. This definition is specifically intended to include, although it is not limited to, the 65 KD, 30 KD, 25 KD and 47 KD proteins which have already been discovered and are discussed herein.. Because of the structural similarities of heat shock proteins throughout nature, the presence of hHSP65 can be detected by polyclonal or monoclonal antibodies specifically raised against the heat shock protein of any organism. For example, the heat shock protein of M. tuberculosis (MT) can be readily produced in high quantity by genetic engineering techniques. This protein can be used to raise antibodies in rabbits or mice. The polyclonal rabbit anti-MT-hsp65 antibodies can be used in accordance with the present invention to assay for the presence of hHSP65. Similarly, monoclonal antibodies obtained from the spleens of mice immunized against MT hsp65 can be selected which react with MT hsp65. Such monoclonal antibodies will also cross-react with hHSP65. Those of ordinary skill in the art will know of many ways to raise antibodies reactive or cross-reactive to hHSP65, once one is aware of the diagnostic capabilities of hHSP65. Any of such antibodies may be used in accordance with the present invention. Due to the structural similarities, the hsp of any organism can be used as an immunization agent and the antibodies can be raised in any organism. Any specific monoclonal antibodies used in the examples of the present specification are for the purpose of exemplification only. There is no reason to believe that any one such monoclonal antibody specifically raised for its property of specifically reacting with a given antigen, would be better than any other for the purpose of the present invention. As indicated above, not only can the hHSP65 protein be used as the diagnostic marker, but antibodies against hHSP65 can also be used as such. Antibodies which spontaneously form when hHSP65 is released in the human patient can be assayed. A positive assay for the presence of such antibodies will serve as an indication of impending IDDM to the same extent as an assay for the hHSP65 proteins themselves will serve this purpose. The anti-hHSP65 antibodies may be assayed for by looking for reaction with any hsp65 protein. Thus, the MT hsp65 protein will cross-react with anti-hHSP65 antibodies. Of course, the preferred protein for use in assaying for the presence of anti-hHSP65 antibodies is the hHSP65 protein. However, those of ordinary skill in the art can readily empirically determine, without undue experimentation, whether any given protein or protein fragment will cross-react with anti-hHSP65 antibodies. Simple in vitro tests can be used to determine if any such protein or other molecule will immunoreact with anti-hHSP65 antibodies.. If it does, then it can be used in the method of the present invention and it is intended to be comprehended by the present invention. The following examples show specific embodiments of the present invention and experiments relating to the present invention. These are intended as examples only and are presented in a non-limitative manner. EXAMPLE 1: Production of the MT hsp65 Molecule The hsp molecule of Mycobacterium tuberculosis was transfected into E. coli by standard procedures and purified as described by van Eden et al, Nature, 331:171-173, 1988. Such genetically engineered E. coli cells will produce substantial quantities of MT hsp65. Because of the close homology between hsp's of various sources, hsp65 of mammalian or human origin is also effective when produced by genetic engineering or isolation from cells. EXAMPLE 2: Production of Antibodies to MT hsp65 Rabbits of a standard laboratory strain (New Zealand White) were inoculated subcutaneously in the back with 100 micrograms of MT hsp65 produced in accordance with Example 1, in 0.5 ml saline emulsified in 0.5 ml mineral oil (incomplete adjuvant). One month later the rabbits were boosted with 100 micrograms of MT hsp65 in 1.0 ml saline, and two weeks later the rabbits were bled and the serum collected. The rabbits were boosted in a similar manner after two months and bled again. The sera antibodies were used to detect hsp65 in the blood and urine of test animals and humans. EXAMPLE 3: Assay of hsp65 A standard solid phase radioimmunoassay is used to detect the presence of hsp65 molecule. Flexible PVC microtiter plates are coated with 100 μl test serum or urine for 18 hours at 4° C. and washed with phosphate buffered saline (PBS). Control rabbit serum or anti-hsp65 serum (produced in accordance with Example 2) is then diluted 1:100 in PBS+0.1% bovine serum albumin (BSA), and 50 μl is added to each well and incubated for 2-3 hours at 37° C. The wells are then washed three times in PBS. 125 I-goat anti-rabbit Ig, 100,000 cpm/well, is added and the wells are maintained for two hours at 37° C. The plates are then washed four times in PBS and dried, and the wells are counted in a gamma counter. Values obtained with anti-hsp65 serum 2 S.D. above the mean cpm obtained with normal rabbit serum are considered as positive for the presence of hsp65. EXAMPLE 4: Assay of Anti-hsp65 Antibodies Antibodies to hsp65 are detected in a similar fashion except that the antigen bound to the plates is not test serum or urine, but purified MT hsp65 produced in accordance with Example 1, 5 μm/well. The serum to be tested for anti-hsp65 antibodies is diluted 1:50. Urine is used undiluted. The serum or urine is added to the wells containing hsp65 and the presence of antibodies binding to hsp65 is detected using radiolabelled goat anti-mouse Ig for mouse specimens and goat anti-human Ig for human specimens. The remainder of the assay is done as described in Example 3. Positive results are defined as cpm greater than 2 S.D. above the mean cpm obtained using control sera from healthy mice, rats, or humans. EXAMPLE 5: hsp65 Molecules and Anti-hsp65 Antibodies Detect Development of IDDM Before Its Onset NOD Mice Fourteen female NOD mice were bled beginning on day 21 of life at regular intervals for about 200 days and scored for the development of IDDM. The sera were tested for hsp65, anti-hsp65, anti-insulin antibodies, and anti-idiotypic antibodies to DM idiotype. The hsp65 was tested using the assay of Example 3. The presence of anti-hsp65 antibodies was assayed according to the procedure of Example 4. Anti-insulin antibodies are idiotypic antibodies which recognize the receptor binding sites of insulin, sometimes designated DM-idiotypic antibodies. Anti-idiotypic antibodies are antibodies against DM-idiotypic antibodies, sometimes designated anti-DM-idiotypic antibodies. In U.S. application Ser. No. 07/295,401, owned by the present assignee, it is disclosed that the presence of DM-idiotypic antibodies or anti-DM-idiotypic antibodies in the serum or urine of a patient is a positive indication of incipient or active IDDM. Such antibodies are not present in the serum or urine of healthy patients. The procedures used to assay for the presence of anti-insulin antibodies and anti-idiotypic antibodies are as set forth in said Ser. No. 07/295,401, the entire contents of which are hereby incorporated herein by reference. Ten of the NOD mice developed IDDM and four remained free of IDDM. FIG. 1 shows the results of testing the sera of one mouse that did not develop IDDM, and FIG. 2 shows the results of testing the sera of one of the mice that did develop IDDM. It can be seen that compared to the IDDM free mouse, the mouse that did develop IDDM on day 185 of life developed a markedly elevated concentration of hsp65 beginning on day 85. The hsp65 concentration decreased after IDDM actually appeared. Anti-hsp65 antibodies appeared several weeks after the appearance of hsp65. Anti-insulin and anti-idiotypic (DM) antibodies appeared much later. Thus, elevation of hsp65 and anti-hsp65 preceded clinical IDDM and served as early signs of the subclinical disease process. Table 1 shows the cumulative data obtained from the fourteen individual mice. TABLE 1______________________________________Serum Assay of Impending IDDM in NOD Mice Day of IDDM Days Positive Test Preceded IDDM OnsetMouse onset hsp65 anti-hsp65 anti-insulin anti-idiotype______________________________________1 none 0 0 0 02 none 0 0 0 03 none 0 0 0 04 none 0 0 0 05 185 90 45 45 306 185 100 50 45 207 170 90 60 60 308 170 100 50 30 209 145 60 60 25 1510 145 70 30 15 1511 145 60 40 20 2012 130 50 20 0 013 115 55 55 20 2014 115 50 30 30 20Mean 150.5 72.5 44 29 19SE 8.28 6.47 4.33 5.47 2.67Median 145 65 47.5 27.5 20______________________________________ The mean age of IDDM onset was 150.5 days in the mice developing disease. The mean hsp65 serum test was positive 72.5 days before IDDM and the mean anti-hsp65 test was positive 44 days before IDDM. The anti-insulin and anti-idiotypic antibody tests were positive only 29 and 19 days before IDDM on the average. The tests were not significantly positive in mice escaping IDDM. Therefore, hsp65 and anti-hsp65 are relatively early indicators of eventual development of IDDM. Urine was tested for the presence of hsp65 in the NOD mice at about 100 days of age. Table 2 shows that the urine of the mice tested positive in those mice that did develop IDDM. TABLE 2______________________________________Urine Assay of Impending IDDM in NOD Mice Urines IDDM positive for hsp65______________________________________ Yes 10/10 No 0/4______________________________________ BB Rats Table 3 shows that BB rats that did not develop IDDM did not manifest hsp65 or anti-hsp65 in the serum or urine. Rats that did develop IDDM (on days 90-100) were positive when tested 10 to 20 days before the outbreak of IDDM. The assays were conducted as disclosed in Examples 3 and 4. TABLE 3______________________________________Assays of hsp65 and Anti-hsp65 Associated withDevelopment of IDDM in BB RatsDevelopment Serum Urineof IDDM hsp65 anti-hsp65 hsp65 anti-hsp65______________________________________Yes 10/10 5/5 4/5 3/5No 0/5 0/5 0/5 0/5______________________________________ Human IDDM Patients Sera were available from five patients at various times before they developed IDDM. The sera were obtained from these persons 1/2 to 2 years before the onset of IDDM because they were first degree relatives of known IDDM patients and were thought to be at risk of developing IDDM themselves. In addition to those persons, sera and urines of four newly diagnosed IDDM patients were studied for hsp65. Control sera and urines were obtained from 10 patients with active multiple sclerosis and 35 children seen at a general hospital for a variety of problems not related to IDDM. The results are shown in Table 4. The assays were conducted in accordance with the procedures of Examples 3 and 4. TABLE 4______________________________________hHSP65 and anti-hHSP65 in human IDDM patients Serum UrineHumans hHSP65 anti-hHSP65 hHSP65 anti-hHSP65______________________________________Pre-IDDM 4/5 4/5 N.D. N.D.New IDDM 2/4 2/4 2/4 2/4Multiple 0/10 0/10 N.D. N.D.SclerosisHospitalized 0/35 0/35 N.D. N.D.Children(no IDDM)Healthy adults 0/10 0/10 0/10 0/10______________________________________ It can be seen from the above table that four out of five of the pre-IDDM patents and two out of four of the IDDM patients were positive in the hHSP65 and anti-hHSP65 assays. None of the controls was positive. Thus, anti-hsp65 raised in rabbits against hsp65 of MT can detect hHSP65 in human serum and urine in association with the development of IDDM. Moreover, hsp65 of MT could detect human antibodies. As discussed above, antibodies made to hsp65 of human or other origin can also be used in these assays, as well as hsp65 obtained from human or other sources. This is possible because of the high degree of conservation of hsp's throughout biological evolution. That all of the pre-IDDM and new IDDM patients were not positive is explained by the fact that the concentrations of hHSP65 and anti-hHSP65 tend to decrease at or around the actual time of IDDM onset, as shown in FIG. 2. Thus, the negative patients may have lost their positivity when they were tested close to the onset of IDDM. From the above, it is apparent that human patients will be positive for hHSP65 or anti-hHSP65 at some time early before the onset of IDDM. Assays for hHSP65 or anti-hHSP65 are therefore useful in screening populations for those that may be in the process of developing IDDM. The hHSP65 appearing in the blood or urine of individuals developing IDDM could come from several sources. The sources may be hHSP65 expressed normally by healthy beta cells and released when the beta cells undergo viral infection or toxic insult as a prelude to immunological destruction, or it may be released from the beta cells by the stress of immunological destruction. The hHSP65 might also be expressed by the cells of the immune system during their prolonged activity against the beta cells. Although the sources of hHSP65 in the system are not at this time conclusively known, it has been determined that once the hHSP65 is released, the individual is stimulated to make antibodies to the hHSP65 molecule. Antibodies to an undefined molecule of 64,000 molecular weight have been described in some newly diagnosed IDDM patients by Baekeskov et al. in Nature, 298: 167-168, 1982. However, it is not known whether the 64 KD antigen is an hsp. Moreover, the 64 KD antigen is not known to appear in blood or urine before the onset of IDDM. In contrast to this undefined 64KD beta cell antigen, hsp65 is a defined protein whose amino acid sequence is known (Thole et al, Infection and Immunity, 55:1466-1475, 1987). Similarly, the amino acid sequence of hHSP65 is shown and set forth in FIG. 3A-B. EXAMPLE 6: Study of Male Mice of Strain C57BL/Ksj C57BL/KsJ mice develop IDDM approximately two weeks after receiving five consecutive daily inoculations of the beta cell toxin streptozotocin at doses of 40 mg/kg per day. In the experiments described herein, groups of ten male C57BL/Ksj mice, aged 3 months, were or were not subjected to low-dose streptozotocin injections (40 mg/kg daily×5) to induce IDDM (appearing at day 14) and were investigated for the development of IDDM, as measured by blood glucose higher than 250 mg %, and for the appearance of hsp65 and anti-hsp65 antibodies in the blood. As shown in Table 5, the hsp65 appeared by day 10 (before clinical manifestation of IDDM), followed by anti-hsp65. TABLE 5______________________________________Low-dose streptozotocin model of IDDM in C57Bl/ksj mice:Induction of hsp65 and anti-hsp65 IDDM Cumulative Incidence on DaysAppearance of Streptozotocin 0 5 10 25______________________________________IDDM Yes 0 0 0 100 No 0 0 0 0hsp65 Yes 0 0 90 100 No 0 0 0 0anti-hsp65 Yes 0 0 0 90 No 0 0 0 0______________________________________ EXAMPLE 7: Multiple Murine Molecules are Cross-Reactive with hsp65 of Mycobacteria To identify the mammalian molecules recognized by antibodies to mycobacterial hsp65, the rabbit anti-hsp65 antiserum described above was tested, as was a monoclonal antibody designated as TB78. This antibody was developed and supplied by Dr. J. Ivanyi, of the MRC Tuberculosis Unit, Hammersmith Hospital, London. This antibody is specific for the hsp65 molecule of M. tuberculosis. Three types of preparations were assayed for their binding of these antibodies: Cloned hsp65 of M, tuberculosis; the sera of NOD mice developing IDDM and healthy controls; and lysates of rat fibroblasts treated with heat shock and control fibroblast lysates. Hsp65 was prepared as described in Example 1. Rat embryonic-fibroblasts were cultured using standard procedures. To induce heat shock proteins, cultures of fibroblasts were incubated at 42.5° C. for two hours and then for 1/2 hour at 37° C. The heat shocked fibroblasts and control fibroblasts were cultured at 37° C., and about 5×10 6 cells each were then lysed using a lysis buffer composed of 0.1% SDS and 1% Triton together with protease inhibitors. The protein concentration was adjusted by Bradford determination to 2 mg/ml. The material was run in 10% polyacrylamide gel, 100 micrograms per lane, for standard electrophoresis, under reducing conditions (2% 2-mercaptoethanol). Mouse sera from healthy control mice and from NOD mice developing IDDM were diluted to a concentration of 2 mg/ml. Each of these serum preparations was separated by polyacrylamide gel electrophoresis as above. The separated proteins were then transferred overnight to nitrocellulose paper by standard procedures. The papers were then incubated for one hour at room temperature with 1% hemoglobin (for blocking) and then with either normal rabbit serum or anti-hsp65 at a dilution of 1:100, or with TB 78 or a control monoclonal antibody at dilutions of 1:100 for two hours at room temperature. Binding of the antibodies to any of the separated bands was detected by incubation with 125 I-radiolabelled goat anti-rabbit Ig or goat anti-mouse Ig, washed and developed by autoradiography. Molecular weight standards were included. It was found that several bands were detected by the anti-hsp65 antibodies. Mycobacterial hsp65 was detected by both the rabbit antiserum and monoclonal TB68. The antibodies also recognized a 65 KD band in the murine fibroblasts that was expressed in an augmented fashion after heat shock. In the heated fibroblast lysates there were also positive bands at 30 KD and 47 KD. An additional band at about 25 KD was detected in the sera from the NOD mice developing IDDM. Therefore, mammalian molecules of 65 KD, 47 KD, 30 KD and 25 KD are cross-reactive with mycobacterial hsp65. EXAMPLE 8: Hsp65 is Expressed in the Islets of the Pancreas Because the development of IDDM is accompanied by augmented expression of hsp65 in the blood and urine, it was thought that the beta cells in the islets might be the source of the hsp65. In order to test this theory, rabbit anti-hsp65 was tested to see if it would bind to islet cells. A standard procedure was used to prepare frozen sections of rat pancreas, 6-8 microns thick. The sections were overlaid with normal rabbit serum or anti-hsp65 anti-serum (absorbed with liver powder to remove non-specific antibodies) diluted 1:50 and incubated for 30 minutes at room temperature, thoroughly washed with PBS, and then incubated for 5 minutes with 5% normal goat serum before incubation with fluorescein labelled goat anti-rabbit Ig for 30 minutes at room temperature, washed with PBS and examined using a fluorescence microscope. The islets were brightly stained by the anti-hsp65 antiserum, but not by the control rabbit serum. Therefore, islets express hsp65. EXAMPLE 9: Immunization to hsp Induces IDDM Since it was found that islet cells express hsp65, it was postulated that an anti-hsp immune response would damage beta cells and thereby induce IDDM. Male C57BL/KsJ mice, 8 weeks old, or female NOD mice, 4.5 weeks old, were immunized by intraperitoneal injection with 50 μg of hsp65 and tested as to whether they might develop IDDM, as evidenced by blood glucose greater than 250 mg %. At 4.5 weeks of age, the NOD mice were at least three months before spontaneous IDDM. The C57BL/Ksj mice do not develop spontaneous IDDM. The hsp65 was administered emulsified in oil or in PBS. Bovine serum albumin (BSA) emulsified in oil was used as a control. The results are shown in Table 6. It was found that hsp65 in oil, but not in PBS, induced IDDM. Therefore, an immune response to hsp65 can trigger IDDM, probably because the beta cells express an antigen cross-reactive with hsp65. TABLE 6______________________________________ Incidence of IDDM 3 weeksmice antigen adjuvant later______________________________________NOD hsp65 oil 7/10 hsp65 PBS 0/10 BSA oil 0/20C57BL/ksj hsp65 oil 6/7 hsp65 PBS 0/9 none none 0/15______________________________________ In an additional experiment, strains of normal mice which do not develop IDDM spontaneously, as do NOD mice, or even after low dose streptozotocin, as do C57BL/ksJ mice, were inoculated intraperitoneally with 50 μg of antigen, either hsp65 or bovine serum antigen (BSA) emulsified in incomplete Freund's adjuvant (oil). The mice were bled in the morning 19 days later and blood glucose was measured. IDDM was diagnosed by a concentration of blood glucose greater than 200 mg%. The results are shown in Table 7. It can be seen that immunization with hsp65 can induce IDDM even in some apparently normal strains of mice, particularly when administered in an appropriate dosage. This supports the conclusion that hsp65 or molecules immunologically cross-reactive with hsp65, are target antigens in IDDM. TABLE 7______________________________________Immunization to hsp65 Induces IDDM in Non-DiabeticStrains of Mice Blood Glucose (mg %) IDDM Incidence antigens antigensMouse Strain hsp65 BSA hsp65 BSA______________________________________C3H.eB/Fej 270 ± 41 96 ± 32 5/5 0/5C57BL/6j 298 ± 52 122 ± 26 5/5 0/5DBA/2 146 ± 33 126 ± 21 0/5 0/5SJL/j 162 ± 27 139 ± 26 0/5 0/5______________________________________ EXAMPLE 10: hsp65 Can Induce Resistance to Induction of IDDM It is well established that antigen administered without an effective adjuvant, or with a tolerogenic carrier, can induce immunological non-responsiveness, i.e., specific tolerance to the antigen. Therefore, mice that had been injected with hsp65 in PBS were tested to determine if these mice had acquired resistance to IDDM induced by hsp65 in oil. One month after receiving hsp65 in PBS, C57BL/Ksj mice were challenged with hsp65 in oil, and none of these mice developed IDDM as measured by blood glucose greater than 250 mg % three weeks later. In contrast, 8 of 10 control mice that had not received hsp65 in PBS developed IDDM after receiving hsp65 in oil. In another experiment, hsp65 was given to 30 day old female NOD mice in PBS, intraperitoneally, 15 days before challenge with 50 μg hsp65 in oil to induce IDDM. The presence of IDDM was measured by blood glucose concentration of greater than 200 mg% 35 days after challenge. The presence of IDDM was again measured when the mice were 5 months of age. At this age it is known that 50% of all untreated female NOD mice have detectable IDDM. The results are shown in Table 8. TABLE 8______________________________________Use of hsp65 to Vaccinate against IDDM Incidence of IDOMhsp65 in PBS 35 days after(μg) challenge 5 months old______________________________________0 7/81 0/8 0/85 0/8 0/850 0/8 0/8______________________________________ Thus, it can be seen that hsp65 can be used to induce tolerance to a diabetogenic immune process. Not only is this tolerance effective with respect to an immunogenic attack of hsp65, but it remains effective as a treatment against the natural development of spontaneous IDDM in NOD mice. EXAMPLE 11: Treatment of Incipient IDDM Using hHSP65 As shown in Example 10, hsp65 can be used to induce resistance to the autoimmune process of IDDM. This appears to be caused by a mechanism of immunological tolerance to the hHSP65 of the beta cells through exposure to exogenous hsp65. Thus, hsp65 can be useful in treating IDDM before the disease becomes clinically evident and the autoimmune process can be arrested before significant, permanent damage is done. The results of the experiment summarized in Table 8 to the effect that the natural development of spontaneous IDDM in NOD mice can be arrested is significant evidence that hsp65, and particularly hHSP65, can be used therapeutically. The autoimmune process begins very early in NOD mice. At the age of one month insulitis can already be detected. IDDM becomes clinically evident at 5 months in 50% of the female mice of this strain. Administration of hsp65 in 30 day old mice stops this natural development. This establishes that treatment can be effective even after autoimmunity to the islets has already begun. The hsp65 can be used as a therapeutic composition which will be effective against continued development of IDDM by creating tolerance to hHSP65 and thus stopping the self-destruction of the beta cells. The active principle for use in such treatment of incipient IDDM can be any material which is immunologically cross-reactive with hHSP65, i.e., it either cross-reacts with polyclonal antibodies raised against hHSP65 or it raises antibodies which cross-react with hHSP65. Such material, be it a peptide, protein, carbohydrate or other substance, if administered in a tolerogenic manner, will serve to induce tolerance to hHSP65 by virtue of this cross-reactivity. If the substance is an hsp65 protein, it can come from any species. The substance need not be an entire protein in order to be immunologically cross-reactive with hHSP65. It could be a fragment of the protein which retains the antigenic activity of the protein itself. Indeed, it may even be the 9 amino acid peptide sequence (180-188) of the hsp65 of MT identified as the immunologically active portion of hsp65 insofar as adjuvant arthritis is concerned in Van Eden et al, supra, the entire contents of which are hereby incorporated by reference. Routine experimentation will determine whether any given substance is cross-reactive with hHSP65. If the substance cross-reacts with a polyclonal antibody raised against hHSP65 or if it raises antibodies which are cross-reactive with hHSP65, then it is intended to be within the scope of the present invention insofar as therapy of incipient IDDM is concerned. Additional verification of the capability of such a substance to be operable in human therapy would be by means of testing for induction of tolerance in the mouse test described in Example 10. Such experimentation would be routine and would not involve undue experimentation. The preferred compound for treatment of human IDDM is hHSP65. The amino acid sequence of a human heat shock protein has now been elucidated and is set forth in FIG. 3A-B. This protein may be used for this purpose. Besides the hsp65 protein discussed herein, salts, functional derivatives, precursors and active fractions thereof having the ability to immunologically cross-react with hHSP65 may also be used. Sequences such as those of FIG. 3A-B or those disclosed in Van Eden et al, supra, in which one or more amino acids are deleted or replaced with other amino acids, are intended to be encompassed by the present invention as long as they have the ability to immunologically cross-react with hHSP65. As used herein the term "salts" refers to both salts of carboxyl groups and to acid addition salts of amino groups of the protein molecule. Salts of a carboxyl group may be formed by means known in the art and include inorganic salts, for example, sodium, calcium, ammonium, ferric or zinc salts, and the like, and salts with organic bases as those formed, for example, with amines, such as triethanolamine, arginine or lysine, piperidine, procaine and the like. Acid addition salts include, for example, salts with mineral acids such as, for example, hydrochloric acid or sulfuric acid, and salts with organic acids such as, for example, acetic acid or oxalic acid. "Functional derivatives" as used herein covers derivatives which may be prepared from the functional groups which occur as side chains on the residues or the N- or C- terminal groups, by means known in the art, and are included in the invention as long as they remain pharmaceutically acceptable, i.e., they do not destroy the activity of the protein and do not confer toxic properties on compositions containing it. These derivatives may, for example, include aliphatic esters of the carboxyl groups, amides of the carboxyl groups by reaction with ammonia or with primary or secondary amines, N-acyl derivatives of free amino groups of the amino acid residues formed with acyl moieties (e.g., alkanoyl or carbocyclic aroyl groups) or O-acyl derivatives of free hydroxyl group (for example that of seryl or threonyl residues) formed with acyl moieties. "Precursors" are compounds formed prior to, and converted into, hsp65 in the animal or human body. As "active fractions" of the substantially purified protein, the present invention covers any fragment or precursors of the polypeptide chain of an hsp65 protein molecule alone or together with associated molecules or residues linked thereto, e.g., sugar or phosphate residues, or aggregates of the protein molecule or the sugar residues by themselves,.provided said fraction has the ability to immunologically cross-react with hHSP65. It is critical that the active principle described above be administered in a manner which will induce tolerance rather than inducing an immunogenic response. Thus, it should not be administered in oil or any other immunogenic adjuvant. A preferred way of administering the active principle such that it will induce tolerance is to administer it with a carrier that favors induction of tolerance to the antigen when the antigen-carrier conjugate is administered. Such carriers are known as tolerogenic carriers. Examples of known tolerogenic carriers are polymers of D-amino acids, polyethylene glycol, polymers of sugar molecules, self-IgG molecules, self-spleen cells, and fatty acid molecules. An antigen may also be administered in a monomeric highly soluble form to induce tolerance. Another known method of inducing tolerance to an antigen is to administer it orally, even without any carrier specifically chosen for its tolerogenic characteristics. Particular manners of administering an antigen so as to induce tolerance are known to those of ordinary skill in the art and any such manner may be used in accordance with the present invention. Such techniques are not, per se, part of the present invention. Such a tolerogenic composition may be administered as a vaccine for the prevention of the development of IDDM, for example in family members of IDDM patients who may be genetically at risk for the development of IDDM. Preferably, however, the composition is used to stop the continued development of IDDM in persons having detectable hHSP65 in the blood or urine but preferably before they have developed an immune response to the hHSP65. Induction of tolerance will prevent that immune response and therefore prevent the damage (IDDM) caused by an uncontrolled anti-hHSP65 response. However, it is not too late to use the composition of the present invention as treatment even after the appearance of anti-hHSP65 antibodies. The experiment the results of which are shown in Table 8 establishes that the present invention can serve to stop the immune response even after autoimmunity to the islets has already begun. As the autoimmune process may take years in humans, even down-regulation of the response would be beneficial. The composition in accordance with the present invention may be administered orally or parenterally, such as subcutaneously, intramuscularly, intravenously, intranasally or intrarectally. The pharmaceutical tolerogenic compositions may be prepared in a manner known in the art. As shown from the above experiments, islet cells and heat shocked fibroblasts release molecules cross-reactive with mycobacterial hsp65. The fact that immunization of mycobacterial hsp65 can cause IDDM indicates that an immune attack against antigens cross-reactive with mycobacterial hsp65 damages beta cells. Such an immune response could occur as a primary event following accidental immunization to a cross-reactive hHSP65 or an invading microbe. The release of hHSP65 could also arise subsequent to beta cell damage inflicted by a virus or toxins. Thus, it can be understood why the appearance of the hsp65 positive molecules in the blood and urine is an early sign of developing IDDM, because the molecules are released from the beta cells as damage proceeds. Similarly, anti-hHSP65 antibodies are a reliable sign of impending IDDM because an immune response to hHSP65 can itself cause IDDM. Whether the antibodies to hHSP65 are originally raised following accidental immunization or following release of hHSP65 subsequent to beta cell damage inflicted by a virus or toxins, production of anti-hHSP65 antibodies or anti-hHSP65 T-cells could enhance and perpetuate the process of beta cell destruction as the hHSP65 contained on the beta cells themselves will be attacked. This reasoning helps to explain how induction of tolerance or suppression of an immune response to hHSP65 could prevent or cure the diabetic process even after it was initiated. Thus, hsp65, low molecular weight molecules (25, 30 or 47 KD) cross-reactive with hsp65, or fragments, modifed peptide sequences, synthetic peptides or even organic molecules based on the fusion-protein blueprint and designed so as to satisfy the physico-chemical requirements of hsp65, can be used to prevent or treat the IDDM process, as long as they are cross-reactive with polyclonal antibodies raised against hHSP65 or they raise antibodies which are cross-reactive with hHSP65. The presence or incipience of IDDM can also be diagnosed by testing for the presence of any antibody that cross-reacts with hHSP65. Alternatively, this diagnosis can be made by testing for any protein which immunoreacts with an antibody against hHSP65. As noted above, hsp65 is known to be associated with adjuvant arthritis in rats and with rheumatoid arthritis in humans. There would be no uncertainty regarding the assay of hsp65 or anti-hsp65 in discriminating between persons developing IDDM and those suffering from arthritis because, unlike the IDDM process, the process of arthritis is manifested clearly by blatant signs and symptoms of arthritis. Hence, detection of hsp65 or anti-hsp6without signs or symptoms of arthritis would serve to call attention to the possibility of subclinical beta cell destruction and incipient IDDM. Additional tests such as antibodies to beta cells could then be used to confirm a diagnosis of autoimmunity to beta cells. The association of hsp90 with systemic lupus erythematosus (SLE) would also not be confused with the IDDM process because SLE is also characterized by clear signs and symptoms of illness, while the IDDM process is clinically silent. The hsp65 can be used for the diagnosis of IDDM in which the hsp65 is injected subcutaneously into a patient, and the occurrence of a detectable skin reaction is observed. Alternatively, hsp65 is contacted with a patient's blood or blood component, and the occurrence of any immunological reaction with anti-hHSP65, i.e., any antibody which cross-reacts with hsp65, present in the patient's blood is detected by any known immunological method. Such well known immunological methods include radioimmunoassay, fluorescent immunoassay, ELISA, chemiluminescent assay, and the like. In the in vivo skin test, the skin reaction at the site of the injection is measured after a sufficient time period, for example, 24 to 72 hours after administration. Swelling and/or redness is due to a delayed hypersensitivity-like reaction. In the in vitro tests with blood or blood components, hsp65 is contacted, for example, with peripheral blood cells. Lymphocytes of positive patients are stimulated by hsp65 in that they will proliferate and/or produce biologically active factors, such as interleukins or products involved in the degradation of cartilage. Such reactions can be detected by methods well known in the art. For the in vitro serological tests, serum of a patient is contacted with hsp65. If the serum contains antibodies against antigenic determinants of hsp65, an immunological reaction will occur which may be detected and assayed by means of standard techniques such as ELISA, agglutination, etc. Any well known immunoassay technique can be used to detect the presence of hHSP65 or anti-hHSP65. It should be understood that once one of ordinary skill in the art becomes aware of the fact that the presence of anti-hHSP65 antibodies in the serum of a person, determined by means of assay with hsp65, is a positive indication of incipient or existing IDDM, such artisans would be well aware of the types of immunoassay technique which can be used. Besides radioimmunoassay (solid or liquid phase), any conventional immunoassay technique can be used, such as enzyme-linked immunosorbent assay (ELISA), heterogeneous immunoassay (both competitive and non-competitive) using labels other than enzymes and radioisotopes, homogeneous immunoassays based on fluorescence quenching and enzyme channeling, immune precipitation (including radial immune diffusion) and agglutination assays based on visual semiquantitative detection or quantitative turbidimetric detection. The assay may use any conventional solid phase or sandwich assay techniques. Similarly, kits may be prepared for carrying out any of the various assays used for accomplishing the present invention. Each such kit would include all of the materials necessary to conduct a single assay or a fixed number of assays. For example, such a kit for determining the presence of anti-hHSP65 antibodies may contain solid-phase immobilized hsp65 and a tagged antibody capable of recognizing the non-variable region of the anti-hHSP65 antibody to be detected, such as tagged anti-human Fab. A kit for determining the presence of hHSP65 may contain solid-phase immobilized antibody which reacts or cross-reacts with hHSP65, and a tagged antibody capable of reacting with a different epitope of hHSP65 than that recognized by the immobilized antibody. The kit should also contain reagent capable of precipitating immune complexes of hsp65 and anti-hHSP65 antibodies and may contain directions for using the kit and containers to hold the materials of the kit. Any conventional tag or label may be used, such as a radioisotope, an enzyme, a chromophore or a fluorophore. A typical radioisotope is iodine-125 or sulfur-35. Typical enzymes for this purpose include horseradish peroxidase, α-galactosidase and alkaline phosphatase. The hsp65 can be used as immunogen in pharmaceutical compositions, particularly vaccines for the alleviation and treatment of IDDM, as well as antigens in diagnostic compositions for the diagnosis of IDDM. These pharmaceutical and diagnostic compositions, which may be prepared in a manner known in the art, also form part of the present invention. Another way to improve the efficacy as a vaccine or therapeutic agent of the hsp65 is to construct, by known genetic engineering methods, microorganisms expressing the hsp65 either as such or as part of a fusion protein or as a multimer thereof. These microorganisms themselves can be used for the preparation of a live vaccine which will provoke not only the production of antibodies against the micro-organism in question, but will also be useful for the alleviation and treatment of IDDM. These genetically engineered microorganisms, and pharmaceutical compositions containing these, are also part of the present invention. Examples of suitable genetically engineered microorganisms are Vaccinia and Salmonella strains. Diagnostic compositions according to the present invention are prepared by combining hsp65 with suitable adjuvants and auxiliary components. The foregoing description of the specific embodiments will so fully reveal the general nature of the invention that others can, by applying current knowledge, readily modify and/or adapt for various applications such specific embodiments without departing from the generic concept, and therefore such adaptations and modifications are intended to be comprehended within the meaning and range of equivalents of the disclosed embodiments. It is to be understood that the phraseology or terminology herein is for the purpose of description and not of limitation.

A 65 KD heat shock protein, proteins cross-reactive therewith, or antibodies thereto can be used for detecting in humans the existence of, a tendency to develop, or the initiation of a process leading to insulin dependent diabetes mellitus. Antibodies to hsp65 can be used to detect the hsp65 molecule in blood or urine. The hsp65 molecule of any species, or any other substance immunologically cross-reactive therewith, when administered with a tolerogenic carrier, can be used for the prevention or treatment of IDDM prior to development of clinical symptoms thereof.

This is a continuation of application Ser. No. 08/419,320, filed Apr. 10, 1995, now U.S. Pat. No. 5,712,669 which in turn is a continuation of application Ser. No. 08/055,623, filed Apr. 30, 1993, now abandoned. BACKGROUND OF THE INVENTION The present invention relates to ink-jet printers, and more particularly to improvements in a common cartridge platform used for different printheads. Ink-jet printers are in widespread use today for printing functions in personal computer, facsimile and other applications. Such printers typically include replaceable print cartridges which hold a supply of ink and carry the ink-jet printhead. The cartridge typically is secured into a printer carriage which supports one or a plurality of cartridges above the print medium, and traverses the medium in a direction transverse to the direction of medium travel through the printer. Electrical connections are made to the printhead by flexible wiring circuits attached to the outside of the cartridge. Each printhead includes a number of tiny nozzles defined in a substrate and nozzle plate structure which are selectively fired by electrical signals applied to interconnect pads to eject droplets of ink in a controlled fashion onto the print medium. In order to achieve accurate printing quality, each removable cartridge includes datum surfaces which engage against corresponding carriage surfaces to precisely locate the cartridge when inserted into the carriage. In this manner, when a cartridge ink supply is exhausted, the cartridge may be replaced with a fresh cartridge, and the printhead of the new cartridge will be precisely located relative to the carriage. As improvements have been made in the printhead design or in the ink delivery system for cartridges, it has been the common design practice to design entirely new printer cartridges, incurring expenses in the design and tooling for the new cartridges. Thus, if a new printhead is developed which has different physical size parameters from an earlier design of a printhead, advancing for the sake of example, from a 180 dpi to a 300 dpi resolution, the common practice has been to develop an entirely new cartridge platform to support the new printhead, including different datum surfaces, and indeed, requiring a new printer carriage to support the cartridge. It is known, in a one-cartridge printer application, to change the nozzle firing frequency, along with the width of the ink feed slots in the substrate die, without changing the datum structure or ink delivery system in an inkjet cartridge, to achieve improved printing performance. In a series of printers marketed by Hewlett-Packard Company, the "Deskjet" series, two different cartridges are available for use in the same printer, one having a relatively lower ink capacity than the other. In this case, the high and low ink capacity cartridges employ the same datum structure, but different ink delivery systems. In one instance, even though the shape and configuration of the nozzle plate and substrate have not been changed, the size of nozzle plate orifices and substrate firing resistors have been changed, to adapt a particular ink-jet cartridge design to a new ink of different viscosity. In another instance, an existing cartridge designed for black ink was modified to operate with color ink, by changing the nozzle orifice size and substrate firing resistor size, reducing the number of active nozzles, and making slight dimensional variations to the substrate die and nozzle plate, in order to adapt the printhead to different fluidic properties of another ink, while using the same datum structure and ink reservoir system. Commonly assigned U.S. Pat. No. 4,872,027 describes an ink-jet printer having identifiable interchangeable printheads which are interchangeably attachable to the printer carriage. The heads are provided with individual codes read by the printer control system to reconfigure its control functions to suit the control requirements of the identified head. It is therefore an object of this invention to provide a method for designing a cartridge which incorporates a common datum structure and ink delivery system from another cartridge design to support a different printhead with different printing characteristics, thereby allowing the development expenses and tooling costs for the common structure to be spread over more than one cartridge. A further object is to provide a family of ink cartridges, each of which employs a common datum structure and common ink reservoir system but with physically different printheads. SUMMARY OF THE INVENTION This invention in a general sense is a method for constructing an ink cartridge for an ink-jet printer, employing common structure from another ink cartridge to realize a savings in development and manufacturing expenses. The method includes the step of selecting a first preexisting cartridge design for an ink-jet cartridge, the first design characterized by a first datum structure, a first ink reservoir system, and a first printhead structure. The printhead structure includes the ink channel leading from the ink reservoir system, the headland structure, the printhead substrate and nozzle plate, and the electrical interconnection circuit for providing control signals to the substrate. The method further includes the step of utilizing the first datum structure and the first ink delivery system in a second ink cartridge design also characterized by a second printhead structure, wherein the first and second cartridge designs share common datum structures and common ink delivery systems. A new printhead structure is provided for the second cartridge which is physically different in shape or configuration than the printhead structure for the first cartridge. In a preferred application, the new printhead structure is designed to provide a printing resolution which is greater than the printing resolution provided by the first ink cartridge. The particular changes which can be made to the printhead structure to increase the resolution include decreasing the spacing between nozzles and increasing the number of active nozzles; these changes generally, but not necessarily, include a change in the size of the substrate die. The invention further is characterized by a family of ink cartridges for ink-jet printers having a common platform. The family includes a first ink cartridge, comprising a first registration datum structure for registering the position of the first ink cartridge in a printer carriage, a first ink reservoir system and a first printhead structure. A second ink cartridge includes a second registration datum structure for registering the position of the cartridge in a printer carriage, a second ink reservoir system and a second printhead structure. The first and second datum registration structures and the first and second ink reservoir systems are substantially identical. The second printhead structure is physically different in shape or configuration from the first printhead structure. As a result of the new method and cartridge system, significant savings in development and manufacturing costs can be achieved, and the time necessary to bring a new cartridge to the market with different print characteristics can be substantially reduced. BRIEF DESCRIPTION OF THE DRAWING These and other features and advantages of the present invention will become more apparent from the following detailed description of an exemplary embodiment thereof, as illustrated in the accompanying drawings, in which: FIG. 1 is an isometric view of a first ink-jet cartridge employing a given datum structure and ink delivery system with a first printhead structure. FIG. 2 is a partial, broken-away isometric view of a second ink-jet cartridge employing the same datum structure and ink delivery system as in the cartridge of FIG. 1, but with a different printhead configuration. FIG. 3 illustrates the headland structure of the cartridge of FIG. 1. FIG. 4 illustrates the headland structure of the cartridge of FIG. 2. FIGS. 5 and 6 are end views showing a simplified nozzle plate attached to the structure of the snout regions of the cartridges of FIGS. 1 and 2. FIG. 7 is an end view of the snout region of a third cartridge employing the same datum structure and ink delivery system of the cartridges of FIGS. 1 and 2, but with yet another printhead configuration. FIG. 8 is a plan view of an ink-jet cartridge as in FIG.1, showing the common structure of the cartridges of FIGS. 1, 2 and 3, and the printhead headland structure area which is not common to the three cartridges. FIG. 9 is a schematic diagram illustrating the common and variable structure in a family of cartridges embodying this invention. FIGS. 10A and 10B are isometric views of a cartridge peripheral housing structure member illustrating an exemplary embodiment of datum structures for a cartridge. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT FIG. 1 illustrates in isometric view a first ink-jet cartridge 50, which generally includes a housing 52 which houses an ink delivery system including an ink reservoir (not shown). An ink delivery system suitable for the cartridge 50 is described in co-pending, commonly assigned applications "Collapsible Ink Reservoir Structure and Printer Ink Cartridge," Ser. No. 07/929,615, filed Aug. 12, 1992, by George T. Kaplinsky; and "Ink Pressure Regulator for a Thermal Ink-Jet Printer," Ser. No. 07/928,811, filed Aug. 12, 1992, by Tofigh Khodapanah et al. The entire contents of both applications are incorporated herein by this reference. The housing structure 52 in this embodiment comprises a peripheral housing structure 52A, fabricated of a molded engineering plastic. Metal cover plates 52B are assembled to the structure 52A to complete the housing enclosure, as more particularly described in commonly assigned "Thermal Ink-Jet Pen with a Plastic/Metal Attachment for the Cover," Ser. No. 07/994,810, filed Dec. 22, 1992, by D. Timm, Jr. et al., the entire contents of which are incorporated herein by this reference. The housing structure 52 defines a number of datum surfaces, used to precisely position the cartridge 50 within a printer carriage. The structure 52 is shown in isolation in the isometric view of FIGS. 10A and 10B. As shown therein, the structure 52 includes three X axis datum structures X1, X2 and X3, two Y axis datum structures Y1 and Y2, and one Z axis datum structure. A cartridge employing this datum structure is described in commonly assigned application, "Side Biased Pen Datum Scheme for Thermal Ink-Jet Cartridge," Ser. No. 08/057,241, filed Apr. 30, 1993, by D. Swanson et al., the entire contents of which are incorporated herein by this reference. The datum structures typically abut against corresponding datum structures defined on the printer carriage when the cartridge is pushed into place in the carriage. The cartridge 50 further comprises a protruding snout region 56, and a headland region 62 extending at the snout end on which the cartridge ink-jet printhead 70 is mounted. The datum structures for the cartridge are located away from the headland structure, permitting variations to the headland structures without requiring modifications to any datum structures. A printhead 70 includes a thin flexible interconnection circuit carrier 72 which carries a plurality of electrical interconnection pads 74 which make electrical contact with corresponding pads defined in the print carriage socket for the cartridge, when the cartridge is installed in the socket. The pads 74 are connected via wiring traces defined in or on the circuit 72 with active ink-jet firing elements comprising the assembly indicated generally as assembly 76 in FIG. 1. A printhead substrate 76A and a nozzle plate 76B, schematically illustrated in FIG. 9, are secured together to comprise the assembly 76. The substrate/nozzle plate assembly 76 is attached with the flexible carrier 72. In this cartridge embodiment, the carrier 72 wraps around the headland region, and is aligned in position during assembly relative to the datum structure by use of holes 64. Flexible carriers are attached directly to the headland and housing structure by thermal bonding, by the addition of bonding materials, such as hot melts and thermal plastic films, or by thermal and UV-set epoxies. As shown in FIG. 9, a fluid connection is made to the substrate 76A from the ink reservoir system 55 comprising the cartridge 50, as the flexible circuit carrier 72 is secured in position to the headland structure. This provides a means for delivering ink through the ink channel 57 from the reservoir 55 to the substrate/nozzle plate assembly 76 and to tiny ink-jet nozzles formed in the nozzle plate 76B. By selectively activating the active printhead elements, as is well known in the art, tiny ink-droplets can be expelled through the nozzles to print onto the medium. FIG. 2 is a partial isometric view of a second ink-jet cartridge 100, which includes a housing structure 102 which is identical to the housing 52 of cartridge 50, with identical datum structures defined therein. For example, datum structure X1' of cartridge 100 is identical to datum structure X1 of cartridge 50, datum structure X3' is identical to datum structure X3, and so on. The ink reservoir system for the cartridge 100 is identical to that of cartridge 50. The features of cartridge 100 which may differ from corresponding features of cartridge 50 are the ink channel 117 (FIG. 4) and the printhead structure. In comparison to the pattern of electrical interconnection pads 74 of the flexible carrier 70, the pattern of pads 124 of the flexible carrier 120 shown in FIG. 2 has a greater number of pads, i.e., an additional two shortened rows of pads. This permits a greater number of nozzles comprising the nozzle plate portion 126 to be controlled. For example, the printhead of cartridge 50 may include a nozzle pattern for producing a 300 dot per inch print resolution, and the printhead of cartridge 100 may include a nozzle pattern for producing a 600 dot per inch print resolution. The number of nozzles defined in the nozzle plate assembly 126 is greater than the number of nozzles defined in the plate 76, and the nozzle plate spacing is different. Moreover, it will be seen that the area of the substrate/nozzle plate assembly 126 comprising the printhead structure of cartridge 100 is somewhat larger than the area of the substrate/nozzle plate assembly 76 comprising the cartridge 50. The headland surfaces supporting the respective assemblies 76 and 126 of the two cartridges 50 and 100 are shown in FIGS. 3 and 4, respectively. In FIG. 3, the headland region 62 comprises a flat peripheral surface area 62A, a recessed flat area 62C bounded by a generally rectilinear border 62B, and a pair of rib protrusions 62D extending upwardly from the recessed area 62C. A channel opening 57 provides communication between the printhead substrate/nozzle plate assembly 76 and the ink reservoir system 55. The printhead 70 is secured over the recessed region 62C, and edges of the printhead are bonded all around the peripheral region 62A to provide a leakproof seal of the printhead to the headland region 62. In FIG. 4, the headland region 112 of the cartridge 100 includes a generally flat peripheral region 112A, surrounding a rectilinear recessed region 112C, bounded by a border 112B. Rib members 112E extend upwardly from the recessed area 112C to support the printhead 120. A tapered region 112D tapers down to the ink channel 117. The region 112C of the cartridge 100 is somewhat larger in area than the region 62C of cartridge 50. The assembly 126 in this example is somewhat larger in area than the assembly 76 of FIG. 1, and includes a somewhat larger number of nozzles, thereby also requiring a greater number of interconnect pads 114 to provide control of the operation of the nozzles. FIGS. 5 and 6 are end views showing a simplified substrate/nozzle plate assembly of the cartridges 50 and 100 of FIGS. 1 and 2, respectively. Corresponding identical datum structures Y1 and Y1' and 118 are shown in these top views, further illustrating the commonality of the cartridge structure. The printheads 76 and 120 are shown assembled to the respective headland regions. The somewhat longer length of the nozzle assembly 126 in comparison to nozzle assembly 76 is evident from FIGS. 5 and 6. FIG. 7 shows a third example of a cartridge employing a common platform with cartridge 50 of FIG. 1. The housing 152 is identical with housing 50 of FIG. 1, and employs identical datum structures as those structures comprising housing 50; e.g., datum structure Y1" is identical to structure Y1. Moreover, the cartridge 150 employs the same ink reservoir system employed in the cartridge 50. Only the headland region 162 and printhead 170 are changed from the corresponding elements 62 and 70. In this embodiment, the nozzle assembly 176 is rotated 90 degrees relative to the orientation of the nozzle assembly 76 in FIG. 1, e.g., to provide a low profile printer. In other applications, the nozzle assembly 176 could be oriented at an angle other than 90 degrees. The three ink-jet cartridges 50, 100 and 150 are configured to be used with three different printers A, B and C as shown in FIGS. 5, 6 and 7. In a typical application where the cartridges 50, 100 and 150 have physically different electrical connections, the printers will require different carriage electrical connection circuitry to provide the necessary control signals to the different cartridges 50, 100 and 150. FIG. 8 is a side view of the cartridge 50 of FIG. 1, showing the structure which is unchanged in the design of the cartridges 100 and 150. In the three cartridges 50, 100 and 150, the cartridges share the same ink reservoir system design, the same snout, and the same datum structure design. Only the structure of the headland and the printhead has been changed. The commonality of design elements between the three types of cartridges provides savings in development costs and time, and in manufacturing costs as well. Thus, the three cartridges 50, 100 and 150 comprise a family of ink-jet cartridges which share a common cartridge platform, but which have printhead structures which are physically different in shape or configuration to achieve different printing characteristics. FIG. 9 is a schematic block diagram illustrating in a functional sense the cartridge 50 of FIG. 1 and an exemplary printer carriage 40. The cartridge 50 is secured within the carriage by a physical support structure 42 comprising the carriage 40. The carriage also includes carriage datum structures 44 which interact with the housing 52 or datum structures of the cartridge 50, to precisely register the position of the cartridge within the carriage. The carriage further includes electrical interconnection circuit 46 to make electrical contact with the flexible interconnect circuit 72 of the cartridge 50. This electrical interconnection circuitry is a variable structure, in that its design will be varied, depending on the cartridge interconnection circuitry configuration. Still referring to FIG. 9, the common platform comprising the cartridge 50 includes the housing structure 52, the datum structure X1, X2, X3, Y1, Y2 and Z, and the ink reservoir system 55. The variable structure of the cartridge 50, which can be modified in shape or configuration in accordance with the invention to produce new cartridges with different or improved printing characteristics, is the printhead structure, which comprises the headland 62, the substrate 76A, nozzle plate 76B and the flexible interconnect circuit 72. One or all of the variable features may be physically changed in shape or configuration in accordance with the invention to achieve a desired change or improvement in the printing characteristics of the cartridge. A preferred printing characteristic which is improved is the printing resolution, achieved e.g., by decreasing the spacing between nozzles and increasing the number of active nozzles. In accordance with one aspect of the invention, an ink cartridge for an ink-jet printer can be designed, based in part on the common structure design of another cartridge. The method includes the following steps: selecting a first cartridge design characterized by a first datum structure, a first ink reservoir system, and a first printhead structure; utilizing the first datum structure and the first ink reservoir system in a second ink cartridge design also characterized by a second printhead structure, wherein the first and second cartridge designs share common datum structures and common ink reservoir systems, and wherein the second printhead structure is physically different in shape or configuration from the first printhead structure; and constructing a second ink cartridge in accordance with the second cartridge design, the ink cartridge characterized by a datum structure and ink reservoir structure virtually identical to the first datum structure and first ink reservoir system, and wherein the second printhead structure is physically different in shape or configuration from the first printhead structure. The invention allows the investment in research and development and manufacturing of the common platform to be leveraged into different sectors of the ink-jet printing market. The common ink delivery system also lowers the engineering and manufacturing support costs as compared with the conventional one-printhead, one-ink-delivery-system type of design heretofore employed in the design and manufacturing of cartridges. For example, the invention permits the savings of time to design and build a manufacturing line to construct the cartridges; indeed the same line may in some cases be used to build different cartridges designed in accordance with the invention. Since the same or similar production equipment for a given cartridge production line can be used to produce another cartridge in the same family, the equipment can typically be acquired in a shorter time and for less cost than if an entirely new line were designed and set up. It is understood that the above-described embodiments are merely illustrative of the possible specific embodiments which may represent principles of the present invention. The invention is not limited to specific disclosed embodiments of headland structures, substrate or nozzle plate configurations, interconnect circuits, datum structures, ink delivery systems, or the like. Other arrangements may readily be devised in accordance with these principles by those skilled in the art without departing from the scope and spirit of the invention.

A method for designing a second ink-jet cartridge characterized by a datum structure, an ink reservoir system and a printhead structure, given a first cartridge design, wherein the printhead structure of the two cartridges are different. The method uses a common datum structure and ink reservoir system for both the first and second cartridges, to save on development and tooling expenses. The cartridges differ in the shapes or configurations of the headland structures, the flexible interconnect circuits, the nozzle plates, the ink channels or the printhead substrates.

FIELD OF THE INVENTION This invention relates to fuel regulators for combustion engine applications in power automotive vehicles. BACKGROUND OF THE INVENTION It is known to mount a fuel pressure regulator on a fuel rail assembly to regulate the pressure of the fuel that is supplied to the fuel injectors mounted on the fuel rail. The pressurized fuel that is delivered to the fuel rail is pumped from a fuel tank through a fuel supply conduit and excess fuel is returned from the fuel pressure regulator's return port through a fuel return conduit to the tank. This type of system is called a return type system. A typical fuel pressure regulator used in this system provides a movable wall or diaphragm dividing the regulator into chambers on opposite sides thereof at different pressures. The difference in pressure determines the position of the diaphragm, which in turn determines the size of a flow passage through the regulator. Thus, depending upon the difference in pressure on opposite sides of the diaphragm, the flow through the regulator is regulated to a predetermined pressure. Another type of fuel injection system does not have a fuel return conduit and is called a returnless (non-return or dead head) fuel system. In this system, the diaphragm controls the position of a ball valve which is spring-based toward a valve-seat. Fuel flows past the spring and normally opened ball valve into a compartment on one side of the diaphragm for flow to a fuel rail. The opposite side of the diaphragm may have a vacuum reference. It will be appreciated that the difference in pressure between the chambers on the opposite sides of the diaphragm displaces the diaphragm, which in turn mounts a post for moving the ball valve away from the seat or permitting the ball valve to move toward the seat under the spring bias. Such systems are satisfactory for use in providing fuel to a fuel rail at a predetermined regulated pressure. While such pressure regulators have proven satisfactory, there is a need to maximize performance of the combustion engine to which fuel is supplied from the fuel pressure regulator. A combustion engine should not be supplied fuel that is turbulent or aerated. To avoid turbulent flow and aerated fuel, it is generally desirable to maintain a constant level of fuel within and about the fuel pressure regulator. This requires submersing the fuel pressure regulator in fuel. An added benefit from this is the potential reduction in noise. There has developed a need in the mechanical fuel system for a fuel pressure regulator which provides the desired engine performance for a simple and inexpensive means to keep a fuel pressure regulator submersed in fuel. SUMMARY OF THE INVENTION In accordance with one aspect of this invention, a fuel pressure regulator assembly residing in a fuel tank comprising: a containment assembly for submerging a fuel pressure regulator in fuel; a valve element for regulating a fuel pressure and directing excess fuel flow in a fuel system wherein the valve element rests on a valve seat in a closed position to prohibit the fuel flow; and a fuel cover for directing a fuel flow exiting the fuel pressure regulator assembly into the fuel tank. In accordance with another aspect of this invention, a method for reducing noise and hydrocarbon emissions of fuel in a fuel pressure regulator, the method comprising: providing a containment assembly for containing fuel; regulating fuel pressure in a fuel system wherein a valve element rests on a valve seat in a closed position and the valve element displaces axially off the valve seat in an open position; and submerging the fuel pressure regulator in fuel. It is an object of the present invention to provide a fuel pressure regulator that reduces the turbulence and aeration of the fuel that flows to the combustion engine. It is a further object of the present invention to provide a fuel pressure regulator that dampens the noise or vibration of the system. It is also an object of the present invention to keep the fuel pressure regulator submerged in fuel. BRIEF DESCRIPTION OF THE DRAWINGS The invention will be better understood from the following detailed description of the preferred embodiments thereof, taken in conjunction with the accompanying drawings, wherein like reference numerals refer to like parts, in which: FIG. 1 refers to a cross section view of the fuel pressure regulator according to the present invention. FIG. 2 refers to a cross section view of the fuel pressure regulator with a fuel cover. FIG. 3 refers to a cross section view of the fuel pressure regulator with a fuel conduit to the fuel tank. FIG. 4 refers to a perspective view of a fuel cover. FIG. 5 refers to a perspective view of an alternative embodiment of the fuel cover. DETAILED DESCRIPTION FIGS. 1-3 refer to various embodiments of the submersed fuel pressure regulator assembly 10 in accordance with the present invention. Each embodiment includes a fuel pressure regulator assembly 10 , which comprises a fuel pressure regulator 20 that preferably resides in a fuel tank 30 . Fuel tank 30 may be a fuel reservoir (which resides in a fuel tank) or a fuel tank where the fuel pressure regulator assembly 10 is positioned in the line going to the engine on the supply side or in a returnless system where excess fuel is contained in the fuel tank 30 and only consumed fuel is sent to the engine. As also shown in FIGS. 1-3 , each embodiment includes a housing 40 to contain and house the fuel pressure regulator 20 . Housing 40 acts as a wall to collect fuel spray released from the fuel pressure regulator 20 . The preferred shape of the housing 40 is generally a tubular shape but others skilled in the art may select other shapes including oval, circular, and as necessary for convenient packaging. Likewise, each embodiment includes a valve element 50 disposed on fuel pressure regulator 20 , which allows fuel that is at an excess pressure to exit the fuel pressure regulator 20 , while retaining fuel not at an excess pressure within fuel pressure regulator 20 . The preferred type of valve element 50 may be a convex plate but others skilled in the art may select a flat disk, a biased member, a spring, a ball valve or another equivalent relief-type valve. If the fuel pressure exceeds the desired maximum pressure, the valve element 50 which rests on a valve seat 55 allows excess fuel to exit fuel pressure regulator 20 and the fuel is free to fly out in a variety of directions. Valve seat 55 cooperates with valve element 50 that is movably disposed between an open and closed position. In a closed position, the valve element 50 contacts and seals against the seating surface of the valve seat 55 and prevents fuel flow past the valve seat 55 . Pressurized fuel accumulates in fuel regulator 20 until the pressurized fuel contacts the bottom surface of the valve element 50 . The pressurized fuel will then push valve element 50 off of valve seat 55 into an open position allowing fuel to flow. Valve element 50 may be a free floating design where it is not retained by other components of the assembly. Others skilled in the art may have a valve element 50 fastened to fuel pressure regulator 20 where the valve element 50 includes an aperture (not shown) or other release mechanism (not shown) to release the pressure and fuel accumulating in the fuel pressure regulator 20 . Others skilled in the art may use a hermetic seal, weld, crimp, or clamp to fasten the valve element 50 to the valve seat 55 . A containment means may be utilized to insure that fuel pressure regulator 20 remains submersed in fuel. The expected spray pattern, packaging requirements and other factors will dictate the type and geometry of the containment means utilized in the invention. Three different containment means are described below. In the first aspect of the invention, which is shown in FIG. 1 , the containment means consists of housing 40 , which is used to collect the spray of excess fuel exiting the fuel regulator 20 . Housing 40 is a cylindrical wall that surrounds fuel regulator 20 . The expected spray pattern will dictate the height and geometry of housing 40 . In the preferred embodiment, the height of housing 40 will be at least equivalent to the height of valve element 50 . Housing 40 is extended and designed to stand in a generally upright position to allow substantially all of fuel regulator 20 to be maintained submersed in fuel. Housing 40 must be extended such that fuel tank 30 allows the fuel pressure regulator 10 to sit in a pocket of fuel at all times. This submersion minimizes or reduces the amount of air from entering the fuel supply system going to the fuel rail and thus minimizes air bubbles forming in the fuel. Similarly, if the spray pattern of fuel is spread in a variety of directions including horizontal and vertical spray for example when a vehicle is idling, then the fuel will break the surface of the collected fuel in regulator 20 and consequently make noise and produce free hydrocarbons thus increasing emissions from the tank 30 by shooting against the components of the fuel pressure regulator assembly 10 . Thus a need for a fuel cover 60 would be beneficial in this case. FIG. 2 refers to an alternate embodiment of the fuel pressure regulator assembly 10 with fuel cover 60 . In this embodiment, the fuel cover 60 is not hermetically sealed to the housing 40 . Fuel cover 60 comprises extension tabs 61 and 62 to direct the flow of excess fuel back into fuel tank 30 . FIG. 3 refers to an alternative embodiment of the invention whereby fuel pressure regulator 20 is hermetically sealed in a housing 40 by the fuel cover 60 . Others skilled in the art may select not to hermetically seal the fuel cover 60 to the housing 40 because any leakage of fuel will return back to the fuel tank 30 and therefore does not pose any problems. In this embodiment, any excess fuel is directed to the bottom of fuel tank 30 using fuel conduit 70 . In the preferred embodiment, the inlet 80 of fuel conduit 70 may be positioned near the top of housing 40 such that collected excess fuel may remain above the fuel pressure regulator 20 and then be directed toward the bottom of fuel tank 30 . However, there may be other factors (e.g. packaging requirements) that may warrant a different placement of inlet 80 . Preferably, outlet 85 should be disposed below a fuel fluid level in the fuel tank 30 to prevent air from entering the fuel pressure regulator assembly 10 . FIG. 4 refers to fuel cover 60 . The fuel cover 60 is made of a plastic molded material and also includes at least one snap mechanism 90 allowing ease when being affixed to the housing 40 . In the preferred embodiment, the at least one snap mechanism 90 is a tab acting as a clip to hold the fuel pressure regulator 20 in place. One skilled in the art may choose not to affix a fuel cover 60 to the fuel pressure regulator 20 . Similarly, others skilled in the art may select to hermetically seal fuel cover 60 to housing 40 . Fuel cover 60 also acts to keep the fuel pressure regulator 20 submerged in fuel at all times during fuel flow which enhances durability of the fuel pressure regulator 20 as well as dampen any vibrating noise of the fuel pressure regulator assembly 10 . This aids in durability of the spring (not shown) used in the fuel pressure regulator assembly 10 . The accumulation of fuel in the chamber below the fuel cover 60 and above valve element 50 functions to keep pressure regulator 20 submerged in fuel. This configuration also protects the other regulator components i.e. flat spring (not shown) from damage during handling, shipping, & assembly. Similarly, submergence of the fuel pressure regulator 20 in the fuel ensures that the fuel is not aerated which maximizes engine performance and that the fuel exits regulator in an organized flow back to the fuel tank 30 . Depending on the orientation of the fuel pressure regulator 20 and the fuel cover 60 the fuel cover openings 95 may be facing in a vertical direction which would then allow the flow of fuel to enter from the left and exit on the right. For example, in FIG. 3 , those ordinary skilled in the art may rotate the fuel pressure regulator 90° allowing fuel to enter from the side as opposed to the bottom. FIG. 5 refers to an alternative embodiment of fuel cover 60 . In this embodiment, fuel cover 60 includes as least three snap fit mechanisms 90 to affix the fuel cover 60 to housing 40 . Similarly, fuel cover 60 includes a fuel outlet 100 for directing the fuel path from the fuel pressure regulator 20 back to the fuel tank 30 . The fuel will hit the top surface 110 of the fuel cover 60 and then exit through side fuel outlet 100 to the fuel tank 30 . While the foregoing description and drawings represent the preferred embodiments of the present invention, it will be apparent to those skilled in the art that various changes and modifications may be made therein without departing from the true spirit and scope of the present invention.

The present invention refers to a fuel pressure regulator assembly and method for regulating the pressure of the fuel supplied to the fuel rail at a predetermined pressure. The fuel pressure regulator includes a housing and fuel cover for containing the fuel pressure regulator and submersing the fuel pressure regulator in fuel at all times. A valve element allows excess fuel to exit the fuel pressure regulator and return to the fuel tank for reuse. The fuel component assembly also allows for a method of reducing turbulent fuel flow and for controlling noise and hydrocarbon emissions. The method is achieved by providing a containment assembly that submerges the pressure regulator in fuel for containing and directing fuel flow path.

CROSS REFERENCE TO PRIOR APPLICATIONS This application is a U.S. National Phase application under 35 U.S.C. §371 of International Application No. PCT/JP2008/055595, filed on Mar. 25, 2008. The International Application was published in Japanese on Oct. 1, 2009 as WO 2009/118832 A1 under PCT Article 21(2), which is herein incorporated by reference. FIELD OF TECHNOLOGY The present invention relates to a radiographic imaging device for detecting radiation and outputting an image signal, and in particular, relates to a radiographic imaging device provided with a structure for performing a temperature control using a Peltier element. BACKGROUND OF THE INVENTION Conventional radiographic devices are structured such as illustrated in FIG. 6 . The radiation that is incident into the radiographic device is converted into an electric charge through an x-ray converting layer 2 that is structured from a semiconductor thick-film such as amorphous selenium. This charge is read out by a bias voltage V A that is applied between a bias applying electrode 1 , which is provided on the incident radiation side of the x-ray converting layer 2 , and the ground side of a capacitor Ca, described below, through a TFT substrate 3 that is provided on the side that is opposite of the bias applying electrode 1 . This TFT substrate 3 has pixel electrodes 31 that are disposed in the form of a matrix in order to collect the electric charge, capacitors Ca that are connected to the pixel electrodes 31 , and thin-film transistor elements Tr, with the sources thereof connected to the capacitors Ca. Note that the region wherein a single pixel electrode 31 is able to collect charge shall be termed the applicable pixel DU, below. The TFT substrate 3 has gate lines G wherein the gates of all of the thin-film transistor elements Tr belonging to the same row are connected in common, and data lines G, wherein the drains of all of the thin-film transistor elements Tr that belong to the same column are connected in common, where the number of gate lines G and the number of data lines D are equal to the number of rows and columns, respectively. The charge that is produced in the pixel DU is stored in the capacitor Ca through the corresponding pixel electrode 31 . When the charge that is stored causes the potential of the gateline G of the column to which the pixel DU belongs to reach the ON potential, then the thin-film transistor elements TR is turned ON, and that charge is read out on the dataline of the column to which the pixel DU belongs. The potential of a gateline G for an individual row is controlled by a gate driving circuit 5 . On the other hand, the TFT substrate 3 is held on one of the surfaces of a base substrate 4 , made of aluminum, or the like, and amplifier and A/D converter circuits 6 are disposed on the other surface of this base substrate. The data lines D of the TFT substrate 3 , and charge amps 61 of the amplifier and A/D converting circuits 6 are connected by a flexible circuit board 63 . The charge that is read out to the data line D is converted into a voltage by the charge amp 61 , and after conversion into a pixel value by an A/D converter circuit 62 that is connected to the charge amp 61 , [the data value] is stored to a memory unit 71 . After this process has been performed for all of the pixels DU that are subject to reading, then the pixel values that have been stored in the memory unit 71 are sent to an image processing device 8 . This series of operations is controlled by a controller 7 . (See, for example, Japanese Unexamined Patent Application Publication 2006-325631.) In a radiographic device structured in this way, there is a problem in that changes in temperature can cause damage to the x-ray converting layer 2 , and can cause peeling or cracking of the layer due to differences in the coefficients of thermal expansion from that of the active-matrix substrate on which is formed the thin-film transistor elements, which has the x-ray converting layer 2 . Given this, a radiographic device further comprising a thermistor 91 for detecting the temperature of the x-ray converting layer 2 , a Peltier element 92 for changing the temperature of the x-ray converting layer 2 , and temperature controlling means for controlling a voltage applied to the Peltier element 92 based on the detected temperature, has been proposed. (See, for example, Japanese Unexamined Patent Application Publication 2003-014860.) However, a problem of there being noise in the element arises accompanying the driving of the Peltier element 92 . Experimentation by the inventor has confirmed the superimposition of linear noise, as illustrated in FIG. 7 , in particular. Because the location and timing with which the noise is superimposed is unspecified, there is a problem in that it is not possible to perform uniform corrections. The present inventors, through experimentation, have discovered that this problem occurs when there is variation in the driving voltage for the Peltier element 92 during the interval prior to the completion of the A/D conversion after the beginning of reading of the charge when the gate controlling means are open, and discovered that if the frequency of this fluctuation is high, then the noise becomes remarkable. The object of the present invention is to provide a high-quality image with low noise through controlling the noise in a radiographic device accompanying temperature control using a Peltier element. SUMMARY OF THE INVENTION In order to solve the problem set forth above, the radiographic device according to the present invention comprises: an x-ray converting layer for converting radiation into electric charge; a bias applying electrode, provided at the incident radiation side of the x-ray converting layer; pixel electrodes, provided in the form of a matrix, on the side opposite from a common electrode; a switching element provided corresponding to each pixel electrode; gate controlling means for controlling the opening of the switching element; a charge amp for converting into voltage charge that is read out through the switching element; an A/D converting circuit for converting into a digital value a voltage detected by the charge amp; a temperature detecting element for detecting the temperature of the x-ray converting layer; a Peltier element for changing the temperature of the x-ray converting layer; and temperature controlling means for controlling a voltage applied to the Peltier element; wherein: during the reading interval after the switching element is opened by the gate controller and the reading out of the electric charge has commenced up through the completion of the A/D conversion, the temperature controlling means constrain, to no more than a predetermined frequency, the variations in the control voltage. The predetermined frequency is preferably 0 Hz, where the temperature controlling means preferably perform PWM control of the rise and fall of the control voltage during an interval other than the reading interval after the gate controlling means are opened and the reading out of the electric charge has commenced up through the completion of the A/D conversion. (Operation) The fluctuations of the driving voltage of the Peltier element during the aforementioned interval are controlled, controlling the noise that is superimposed on the image. If the voltage does not vary at all during this interval, then there will be no superimposition of noise caused by the driving of the Peltier element. Furthermore, when controlling the voltage, power corresponding to the difference between the reference voltage and the voltage being controlled (that is, the voltage drop) is wasted. Because heat is produced commensurate with the wasted power, this leads to an increase in temperature of the radiographic device through heating, reducing the heat controlling efficiency. Given this point, while with PWM control it is possible to minimize the wasted power, because this is pulse control, large fluctuations in voltage are produced when the voltage falls or rises. Consequently, the amount of noise superimposed on the image is large. This problem is resolved through control wherein the switching of the Peltier element driving voltage ON and OFF is not performed during the reading interval. The radiographic device according to the present invention is able to provide an excellent image wherein there is no superimposition, onto the image, of noise caused by the driving of the Peltier element, or wherein the that superimposition is controlled. Furthermore, structuring the present invention using PWM control is able to minimize the power consumption and able to eliminate the superimposition of noise due to the driving of the Peltier element. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a block diagram illustrating the schematic structure of a radiographic device as set forth in the present invention. FIG. 2 is a diagram illustrating the control timing of the Peltier element according to a first example of embodiment. FIG. 3 is a diagram illustrating the control timing of the Peltier element according to a second example of embodiment. FIG. 4 is a diagram illustrating the control timing of the Peltier element according to a third example of embodiment. FIG. 5 is a diagram illustrating a structure for the temperature controlling means according to a fourth example of embodiment. FIG. 6 is a block diagram illustrating a schematic structure for a conventional radiographic device. FIG. 7 is an image with superimposed noise obtained from a conventional radiographic device. DETAILED DESCRIPTION OF THE INVENTION A summary of the radiographic device according to the present invention is illustrated in FIGS. 1 ( a ) and ( b ). The temperature controlling means 9 are structured fundamentally identically to the conventional structure illustrated in FIG. 6 , with the exception of the point wherein a controller 7 is connected. The controller 7 obtains a frame synchronizing signal from the image processing device 8 . Here the frame synchronizing signal is a pulse train that is produced with each interval that is an integer multiple of a minimum frame, and that is longer than the x-ray radiation expectation time that is set by an operator in an x-ray generating device, not shown, wherein typically the minimum frame is 33 ms. Depending on the system, the frame synchronizing signal may be static. On the other hand, the frame generating signal is sent also to the x-ray generating device, where x-rays are illuminated towards the radiographic device using the frame generating signal as a reference. The incident x-rays are converted into charge by the x-ray converting layer 2 that is structured from a semiconductor thick-film. The charge is collected in pixel electrodes that are disposed in the form of a matrix on the opposite side from bias applying electrodes 1 , through a bias voltage V A that is applied to the bias applying electrodes 1 that are provided on the incident radiation side of the x-ray converting layer 2 . The accumulated charge is stored in capacitors Ca that are provided corresponding to the individual pixel electrodes 31 . Furthermore, the accumulated charge is read out to the data line D that that is connected to the thin-film transistor elements Tr that belong to the same column, when the thin-film transistor elements Tr that has the source thereof connected to the pixel electrode 31 and the capacitor Cs is turned ON. The controller 7 operates the gate driving circuit 5 to turn the thin-film transistor elements Tr ON sequentially after an x-ray illuminating interval and a blinking interval have elapsed after the frame synchronization signal has gone low. The charge that is read out to the data line D is converted into a voltage by a charge amp 61 that is connected to the data line D, and is converted into a digital value by an A/D converting circuit 62 that is connected to the charge amp 61 , which digital value is stored in the memory unit 71 , where, upon the completion of the reading of all of the applicable pixels DU, after the digital values have been stored to the memory unit 71 , the data that is stored in the memory unit 71 is sent to the image processing unit 8 . Moreover, the controller 7 outputs a reading interval-in-process signal to the temperature controlling means 9 . The temperature controlling means 9 comprise a thermister 91 , a Peltier element 92 , an A/D converting circuit 93 for converting the voltage signal of the thermistor 91 into a digital signal, a D/A a converting circuit 94 for outputting a voltage to the Peltier element 92 , and a CPU 90 . The software loaded into the CPU 90 uses, as inputs, the reading interval-in-process signal that is outputted from the controller 7 and the digital values from the A/D converter circuit 93 , to determine the control voltage value for the Peltier element 92 , outputted into the D/A converting circuit 94 . This software and the structure of the controller 7 are explained in detail in Examples of Embodiment 1 through 3, below. (Example of Embodiment 1) The present example of embodiment will be explained in reference to FIG. 2 . In FIG. 2 , the aforementioned frame synchronization signal (I), the aforementioned x-ray illumination interval (II), the reading interval-in-processes signal (III), the driving voltage (IV) that should actually be applied to the Peltier element 92 , and the driving voltage that is actually applied to the Peltier element 92 (V) are each shown aligned with the respective time marks. The controller 7 , after activating the aforementioned the gate circuit 5 , outputs a reading interval-in-process (III) that is at the H level over the interval until the conversion, to digital values, of the voltages corresponding to each of the pixels DU that are to be read has been completed, and a L level during all other intervals. Note that the frame period is anticipated to be 266 ms, and the reading interval is anticipated to be about 120 ms. The reading period requires a time that is the number of pixels multiplied by (the time required for the voltage in the charge amp 61 to stabilize added to the time for the conversion in the A/D converting circuit 62 ). Note that this reading interval can be shortened by providing a plurality of A/D converting circuits and operating the circuits in parallel. The software relating to the present example of embodiment has a feedback control task for repeating the Steps S 11 through S 15 , below, with a predetermined period. (Step S 11 ) Read the voltage signal value I AD of the thermistor 91 . Also read the reading interval-in-processes signal (III) from the controller 7 . (Step S 12 ) Calculate the current temperature T, through linear approximation, from the value I 1 , read in from the A/D converting circuit 93 when the temperature of the Thermistor 91 is at T 1 , stored in advance, the value I 2 , read in from the A/D converting circuit 93 when the temperature of the thermistor 91 is at T 2 , stored in advance, and from I AD . At its simplest, this is calculated as follows: T ={( T 1 −T 2 )·( I 1 −I AD )/( I 1 −I 2 )}+ T 1 . (Step S 13 ) Determine the voltage value V P that should be outputted to the Peltier element from the relationship between the target temperature T 0 and the current temperature T. At the simplest differential control, V P =α·(T 0 −T), is adequate, where α is a coefficient, and the larger the coefficient, the more rapid the tracking; however, this can also cause hunting, and thus the optimal value should be set in accordance with the thermal time constant of the system. When PID control is used for the control, temperatures T from several times previous through the current temperature are stored in memory, where the integral value and the derivative value may be multiplied by respective coefficients and applied to the aforementioned differential control value. The method by which to determine V P may be replaced easily with other well-known control technologies, and because how this determination is made is not related to the essence of the present invention, detailed explanations thereof are omitted. (Step S 14 ) When the reading interval-in-process signal (III) is at the H level (the interval B in FIG. 2 ), then, in order to prevent a change in V P , the value for V P is calculated again. For example, the driving voltage (V) after control such as in FIG. 2 is obtained through recalculating V P as follows. V p = { V p : ⁢ ⁢  V p - V prev  ≤ V th V prev + V th : ⁢ ⁢ V p - V prev > V th V prev - V th : ⁢ ⁢ V prev - V p < V th [ Formula ⁢ ⁢ 1 ] Note that if V th is set to 0, then when the reading interval-in-process signal (III) is at the H level, then there will be no fluctuation whatsoever in the driving voltage for the Peltier element 92 . This corresponds to the fluctuation frequency of the driving voltage being 0. (Step S 15 ) Output this determined V P to the D/A converting circuit 94 . Store the outputted V P as V prev . Note that the specific period is preferably as short as possible within the scope of processing capability of the CPU 90 . For example, when using a CPU for a combination that operates with a clock that is several dozen megahertz, the period may be in the range of several milliseconds to 20 ms. Faster operations can be anticipated through performing similar operations using logic structured from an FPGA (Field Programmable Gate Array). While in the present example of embodiment there is a recalculation so that the difference from the output value from the previous time is simply no greater than a threshold value, this may be replaced with a variety of different recalculation methods, such as maintaining a history of V P over a specific period previously, and then performing a one-dimensional Fourier transform, and then, after removing components of frequencies higher than a specific threshold value, performing a reverse Fourier transform, to recalculate the V P . That is, insofar as the frequency of the driving voltage for the Peltier element 92 during the reading interval is lower than in the other interval (portion), the method for performing the calculation may be varied in a variety of ways, and all are included within the present invention. (Second Example of Embodiment) A second example of embodiment as set forth in the present invention will be explained in reference to FIG. 3 . As with FIG. 2 , FIG. 3 also illustrates changes in the various signals over time. In the program in the present example of embodiment, the feedback control task repeats the Steps S 21 through 24 , below, with a specific period. Note that, aside from the program, the structures are identical to that of the first example of embodiment, and thus explanations thereof are omitted. (Step S 21 ) Read in the voltage signal value I AD of the thermistor 91 from the A/D converting circuit 93 . (Step S 22 ) This is identical to Step S 12 in the first example of embodiment, and thus the explanation thereof is omitted. (Step S 23 ) This is identical to Step S 13 in the first example of embodiment, and thus the explanation thereof is omitted. (Step S 24 ) Convert the determined V P into a duty ratio D, and send to the PWM task. Store V P as V prev . Here the duty ratio D is calculated as described below. P=V P /V max , where V max is the maximum value that can be outputted by the D/A converting circuit. Consequently, −1≦D≦1. On the other hand, PWM task performs the following steps P 21 through P 25 with a period that is shorter than that of the feedback control task. (Step P 21 ) Read the reading interval-in-process signal (III) from the controller 7 . (Step P 22 ) Determine, as follows, the voltage V S that should be outputted to the D/A converting circuit 94 : V s = { V max : ⁢ ⁢ C ≤ ( D × C max ) ⁢ ⁢ and ⁢ ⁢ D > 0 0 : ⁢ ⁢ C > ( D × C max ) ⁢ ⁢ or ⁢ ⁢ D = 0 - V max : ⁢ ⁢ C ≤ ( D × C max ) ⁢ ⁢ and ⁢ ⁢ D < 0 [ Formula ⁢ ⁢ 2 ] Here C is a counter variable value, where C max is the maximum value for C, and corresponds to the resolution of the PWM waveform. (Step the P 23 ) When the reading interval-in-process signal (III) is at the H level (the interval B in FIG. 2 ), replace V S with V SPrev , which is the previous V S . That is, the status of V S does not change while the reading interval-in-process signal (III) is at the H value. (Step P 24 ) Output, to the D/A converting circuit 94 , the V S that has been determined. Save, as V Sprev , the V S that has been outputted. (Step P 25 ) Increment C. If C>C max , then replace C with 0. In this type of control, the actual waveform that should be used for driving, as illustrated in (IV) of FIG. 3 , is constrained to the waveform such as (V), enabling the PWM control to be performed without changing the driving voltage of the Peltier element 92 during the interval B. Note that because the present example of embodiment is able to control the control period for the PWM and the period for the frame synchronization signal independently of each other, this is useful from the perspective of independence of control. (Third Example of Embodiment) A third example of embodiment according to the present invention will be explained in reference to FIG. 4 . As with FIG. 3 , FIG. 4 illustrates the changes over time in each of the signals. The program, and the like in the present example of embodiment are also identical to that in the second form of embodiment, and the only discrepancies are in the operation of the controller 7 . The controller 7 activates the gate driving circuits 5 sequentially. At this time, a short wait period is inserted each time the gate line G is activated for a specific row. In this state, the reading interval-in-process signal ( 3 ) is outputted so as to be at the H level over the interval from the beginning of driving of the gate line G until the end of the conversion, to digital values, of the voltages corresponding to the pixels DU of the specific row, and so as to be at the L level during all other intervals ( FIG. 4 ). Doing so distributes the interval B over which the state of the signal can be changed. The specific interval may be a single row, or may be about half of all of the rows. Insofar as the x-ray illumination and the reading operation can be performed within the scope of the frame period, preferably the value for the specific rows is as small as possible, and many waiting intervals are inserted. The structure set forth above enables the changes in the driving voltages for the Peltier element 92 to be eliminated during the reading interval, while relaxing the constraint on the PWM waveform. (Fourth Example of Embodiment) The structures for achieving in hardware functions that are identical to those in the second and third examples of embodiment, described above, are illustrated in FIG. 5 as a fourth example of embodiment. Note that the structures aside from the temperature controlling means 9 in the present example of embodiment, and the feedback control for determining the output, with the input being the digital values from the A/D converting circuit 93 , are identical to those in the other examples of embodiment, and thus explanations thereof are omitted. The temperature controlling means 9 in the present example of embodiment comprise a thermistor 91 , a Peltier element 92 , an A/D converting circuit 93 for converting to a digital value the voltage value of the thermistor 91 , a PWM controlling circuit 96 for controlling, with a PWM waveform, the driving voltage of the Peltier element 92 , a sampling hold circuit 95 for holding, over the interval over which the reading interval-in-process signal (III) is at the H level, the output value from the PWM controlling circuit 96 , at the point in time of the rising edge of the reading interval-in-process of signal (III) from the controller 7 , and a CPU 90 . The software that is loaded into the CPU 90 calculates and outputs a duty ratio to the PWM controlling circuit 96 with the digital value from the A/D converting circuit 93 as the input. This function can minimize the power consumption, and can eliminate the superimposition of noise due to the driving of the Peltier element.

A radiation image pickup device comprises temperature control means for maintaining the temperature of an X ray conversion layer to be substantially constant by performing a feedback process for controlling a voltage which is applied to the Peltier element based on the temperature of the X ray conversion layer. The temperature control means starts reading out an electric charge from each pixel (DU), then converts the electric discharge to voltage with a charge amplifier and in a period until an A/D conversion process for the voltage is completed, and restricts a variation in the voltage which is applied to the Peltier element.

The present Application is a Divisional Application of U.S. patent application Ser. No. 11/984,043, now U.S. Pat. No. 7,704,827, filed on Nov. 13, 2007, and which claims priority from Japanese Patent Application No. 2006-331619, filed on Dec. 8, 2006, the entire contents of which are incorporated herein by reference. BACKGROUND OF THE INVENTION 1. Field of the Invention This invention relates to a semiconductor device and a method for manufacturing semiconductor device. Particularly, the present invention relates to a vertical MOSFET having a trench gate electrode and a method for manufacturing the same. 2. Description of Related Art With rapid development of microfabrication technology, a semiconductor device continues to be integrated highly. Especially, it is well known that a vertical MOSFET (UMOSFET) having a gate electrode buried in a trench has low on-resistance and high breakdown voltage. Further, high integration is required for lower on-resistance and cost reduction (Japanese Unexamined Patent Application Publication No. 2005-86140 and No. 2001-36074). As one of methods for high integration, it is known that the gate trench is formed deeply in an epitaxial layer so as to shorten an aperture of the gate trench. For another method, it is known that an interlayer insulator is buried completely in the gate trench to shorten the aperture of the trench (Japanese Unexamined Patent Application Publication No. 2003-101027, No. 2000-252468 and U.S. Pat. No. 6,351,009). Hereinafter, a related manufacturing process of UMOSFET, having the interlayer insulator buried in the gate trench completely, will be described. An N-channel type of UMOSFET is taken for instance. As shown in FIG. 9 , an n− type epitaxial layer 82 is formed on a semiconductor substrate 81 by an epitaxial growth. A gate trench 83 is formed to the surface of the n− type epitaxial layer 82 so that the gate trench 83 reaches to the inner of the n− epitaxial layer 82 . A gate insulator 84 is formed on the inner side of the gate trench 83 . Further, a polysilicon 85 as a gate electrode is buried in the gate trench 83 with the gate insulator interposed therebetween. A high temperature oxide film (an HTO film) 86 is formed on the polysilicon 85 and the surface 82 a of the n− type epitaxial layer. A p type diffused base layer 87 and an n+ type diffused source layer 88 are formed on the surface 82 a of the n− type epitaxial layer with ion implantation doping though the HTO film 86 . A boron phosphorus silicate glass film (a BPSG film) 89 is formed on the HTO film 86 . The BPSG film 89 has a flowability. Hence, the surface of the BPSG film 89 is planarized by a heat treatment after forming the BPSG film 89 . An etch-back process is performed from the surface of the planarized BPSG film 89 to the depth of an aperture of the gate trench. So, the HTO film 86 and the BPSG film 89 formed on the n-type epitaxial layer 82 are removed. As shown in FIG. 10 , a source electrode is formed on the entire surface of the semiconductor device. A drain electrode 91 is formed on the back side of semiconductor substrate 81 . Hence, the cell pitch can be reduced, because the interlayer insulator (the BPSG film 89 ) between the gate electrode (the polysilicon 85 ) and the source electrode 90 is buried wholly in the gate trench 83 . In the UMOSFET configured as described above, the polysilicon 85 as the gate electrode is positioned in the lower portion of the gate trench 83 . It is because the BPSG film 89 as the interlayer insulator is buried in the gate trench completely. Hence, it needs to form the n+ type diffused source layer 88 in the lower portion of the gate trench 83 depending on the position of the polysilicon 85 . The process of heat treatment to planarize the BPSG film 89 includes the process to diffuse the n+ type diffused source layer 88 also in order to reduce number of process. Here, this process needs high temperature as to diffuse the n+ diffused source layer 88 sufficiently. However, the thickness of the HTO film 86 between the BPSG film 89 and the n− type epitaxial layer 82 is formed to be thin. It is because the p type diffused base layer 87 and the n+ type diffused source layer 88 are formed by ion implantation doping though the HTO film 86 as described above. Hence, if the heat treatment to planarize the BPSG film 89 is set to be high temperature, the diffusion of boron and phosphorus from the BPSG film 89 to the n-type epitaxial layer 82 is promoted. So, it makes the controllability of the manufacturing the semiconductor device worse. In this way, the UMOSFET having the interlayer insulator buries in the gate trench has the process lower controllability, because impurity like boron and phosphorus diffuse from the BPSG film at the heat treatment. SUMMARY According to one aspect of this invention, there is provided a method for manufacturing a semiconductor device comprising: forming a first oxide film on a surface of a semiconductor layer and a polysilicon in a trench, the trench formed in the semiconductor layer; forming a first diffused layer of a first conductivity type and a second diffused layer of a second conductivity type through the first oxide film; forming a second oxide film on the first oxide film; forming a flowable insulator film on the second oxide film; performing a heat treatment for planarizing the insulator film and diffusing the second diffused layer to prescribe depth; and etching the insulator film. According to another aspect of this invention, there is provided a semiconductor device comprising: a semiconductor layer of a second conductive type; a first diffused region of a first conductive type formed in the semiconductor layer; a second diffused region of the second conductive type selectively formed in the first diffused region; a trench formed in the semiconductor layer; a polysilicon formed in the trench with an insulator intervening; a first oxide film formed on the polysilicon so that the first oxide film is buried in the trench; a second oxide film formed on the first oxide film so that the second oxide film is buried in the trench; a flowable insulator film on the second oxide film. BRIEF DESCRIPTION OF THE DRAWINGS The above and other objects, advantages and features of the present invention will be more apparent from the following description of certain preferred embodiments taken in conjunction with the accompanying drawings, in which: FIG. 1 shows a cross sectional view of the semiconductor device 10 according to a first embodiment; FIG. 2 shows the first process of forming the semiconductor device 10 ; FIG. 3 shows the second process of forming the semiconductor device 10 ; FIG. 4 shows a relationship between temperature (degree Celsius) at a heat treatment and a minimum film thickness t (angstrom); FIG. 5 shows a cross sectional view of the semiconductor device 40 according to a second embodiment; FIG. 6 shows the first process of forming the semiconductor device 40 ; FIG. 7 shows the second process of forming the semiconductor device 40 ; FIG. 8 shows a cross sectional view of another semiconductor device 40 ′ according to the second embodiment; FIG. 9 shows the first process of the related forming process of the semiconductor device; and FIG. 10 shows the second process of the related forming process of the semiconductor device. DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS The invention will now be described herein with reference to illustrative embodiments. Those skilled in the art will recognize that many alternative embodiments can be accomplished using the teachings of the present invention and that the invention is not limited to the embodiments illustrated for explanatory purposes. First Embodiment FIG. 1 shows a cross sectional view of a semiconductor-device according to a first embodiment of the invention. Hereinafter, “n+” means n type semiconductor which n type impurity heavily doped. “n−” means n type semiconductor which n type impurity lightly doped. Likewise, “p+” means p type semiconductor which p type impurity heavily doped. “p−” means p type semiconductor which p type impurity lightly doped. “X direction” means a horizontal direction of drawing sheet and “Y direction” means a vertical direction of drawing sheet. As shown in FIG. 1 , a semiconductor device 10 comprises an n+ type semiconductor substrate 11 . An n− type epitaxial layer 12 is formed on the n+ type semiconductor substrate 11 . A p type diffused base layer 17 (a first diffused layer) is formed on the n− type epitaxial layer 12 . A gate trench 13 is formed on the surface of the p diffused base layer. A plurality of the gate trenches 13 are formed in the X direction. A bottom of the gate trench 13 reaches to the n− epitaxial layer 12 . A gate insulator 14 is formed on an inner wall of the gate trench 13 . A polysilicon 15 is formed on an inner aspect of the gate insulator 14 . The HTO film 16 (a first oxide film) is formed in a lower portion in the Y direction than a surface of p type diffused base layer on the polysilicon 15 . A chemical vapor deposition oxide film (a CVD oxide film) 20 (a second oxide film) is formed so that the CVD oxide film 20 reaches around an aperture of the gate trench 13 . Beside the aperture of the gate trench 13 , an n+ type diffused source layer 18 (a second diffused layer) is formed. A source electrode 21 is formed on the n+ type diffused source layer 18 . The source electrode 21 is connected electrically to the n+ type diffused source layer 18 and the p type diffused base layer 17 . A drain electrode 22 is formed on the backside of the n+ type semiconductor substrate 11 . Next, a method for manufacturing the semiconductor device 10 configured as above is explained hereinafter. FIG. 2 shows a first process for manufacturing semiconductor device 10 . Firstly, the epitaxial layer 12 is formed on the n+ type semiconductor substrate 11 by an epitaxial growth. The gate trench 13 is formed to a surface 12 a of the epitaxial layer so that a bottom of the gate trench 13 reaches to the epitaxial layer 12 . The gate insulator 14 is formed inside the gate trench 13 . The polysilicon 15 is buried in the gate trench 13 with the gate insulator 14 interposed therebetween. The surface of the polysilicon 15 is positioned at a lower portion than the surface of the epitaxial layer 12 a . The HTO film 16 is formed over the polysilicon 15 and the surface 12 a of the n− type epitaxial layer. At this time, as shown in FIG. 2 , p type of impurity is implanted to the surface of the epitaxial layer 12 a through the HTO film 16 to form the p type diffused base layer 17 . In the same way, n type of impurity is implanted to a predetermined portion of the p type diffused base layer 17 through the HTO film 16 . Hence, the n+ type diffused source layer 18 is formed beside the aperture of the gate trench 13 . Next, as shown in FIG. 3 , the CVD oxide film 20 is formed on the HTO film 16 . At this time, the CVD oxide film 20 is formed along a shape of lower layer. Hence, a CVD oxide film 20 a located above the gate trench 13 is deposited with lower position than a CVD oxide film 20 b located above the surface of the epitaxial layer 12 a . The BPSG having a flowability is deposited on the CVD oxide film 20 . A surface of the deposited BPSG film 19 has an asperity along a surface ( 20 a , 20 b ) of the CVD oxide film 20 below the BPSG film 19 (not shown). At this time, a heat treating is performed to planarize the BPSG film 19 , as shown in FIG. 3 . This process of heat treating combines the process to diffuse the n+ diffused source layer 18 injected by ion implantation so that the n+ source layer 18 is diffused as high as the polysilicon 15 . This is for cutting the number of the processes. An etch-back process is performed to the surface of the BPSG film 19 until the surface of CVD oxide film 20 is positioned as high as around the aperture of the gate trench 13 . Hence, the semiconductor device 10 is formed as shown in FIG. 1 . The BPSG film 19 is used for planarization the surface of the CVD oxide film 20 and the HTO film 16 which are not flat as shown in FIG. 1 . For the semiconductor device formed in this way, the CVD oxide film 20 (as shown in FIG. 3 ) formed below the BPSG film 19 can prevent boron and phosphorus of the BPSG film 19 from diffusing to the semiconductor layer (such as p base layer 17 , the n+ diffused source layer 18 and the n− epitaxial layer 12 ). Hence, the n+ diffused source layer 18 is diffused adequately by the heat treating. Concurrently, it can reduce the diffusion of boron and phosphorus the BPSG film 19 includes to the semiconductor layer. As a result, it can enhance a controllability of manufacturing the semiconductor device 10 . It is necessary to set a thickness t of the CVD oxide film 20 , so that the CVD oxide film 20 prevent adequately boron and phosphorus of the BPSG film 19 from diffusing to the semiconductor layer. At a high temperature treatment where process temperature is from 900 to 1100 degree Celsius, a diffusion coefficient of phosphorus is larger than a diffusion coefficient of boron. Hence, it may determine the thickness t of the CVD oxide film 20 considering the diffusion coefficient of phosphorus and production tolerance. Here, phosphorus concentration of the BPSG film 19 is about from 3 to 5 mol % and boron concentration of the BPSG film 19 is about from 10 to 11 mol %. A diffusion coefficient of phosphorus in SiO 2 is about 1×10 −14 (cm 2 /sec) at 1000 degree Celsius. A diffusion coefficient of phosphorus in Si is about 5×10 −13 (cm 2 /sec) at 1000 degree Celsius. A diffusion coefficient of phosphorus in Si at 1000 degree Celsius is about fiftyfold of in SiO 2 . On the other hand, in analysis of SIMS (Secondary Ionization Mass Spectrometer), a depth of phosphorus diffusion in Si after 30 minutes of the heat processing at 1000 degree Celsius is about 1.0 μm. Based on the result in this analysis, it is estimated that a depth of phosphorus diffusion in SiO 2 after 30 minutes of the heat processing at 1000 degree Celsius is about 200 angstrom that is one-fifty of the depth of phosphorus diffusion in Si. As described above, it is estimated that the preferable thickness t of the CVD oxide film 20 is more than 200 angstrom at 1000 degree Celsius of the heat processing. A listing as below shows an estimated preferable minimum film thickness t of the CVD oxide film 20 at 900, 950, 1000 and 1100 degree Celsius estimated in the same way described above. TEMPERATURE AT HEAT TREATMENT FILM THICKNESS t no more than 900 degree Celcius t > 24 angstrom no more than 950 degree Celcius t > 80 angstrom no more than 1000 degree Celcius t > 200 angstrom no more than 1100 degree Celcius t > 1200 angstrom FIG. 4 shows a relation between temperature (degree Celsius) of the heat process and minimum film thickness t of the CVD oxide film 20 . The data of the relation between temperature at the heat process and minimum film thickness in the listing above is plotted on a semi-logarithmic graph. This plotted data is approximated by expression line L. Based on the graph in FIG. 4 , the thickness t of the CVD oxide film 20 can be set more than the value of expression line L for processing temperature after forming the BPSG film 19 . Furthermore, considering an embeddability, cost of manufacturing, variation of etching process to remove the CVD oxide film 20 , the preferable thickness t of the CVD oxide film 20 is 24-10000 angstrom. In the first embodiment, an n channel type of UMOSFET is explained for example, but this invention can be applied to a p type of UMOSFET. Applied to a p type of UMOSFET, advantages of this invention can be obtained. When this embodiment is applied to the p type of UMOSFET, conductivity type of semiconductor device in FIG. 1 is inverted. Second Embodiment FIG. 5 shows a cross sectional diagram of semiconductor device 40 according to a second embodiment of this invention. One feature of the second embodiment is that an NSG film 41 (None-doped Silicate Glass film) (a third oxide film) is formed below the HTO oxide film 16 . Hereinafter, the same number is given to the same composition as the first embodiment. As shown in FIG. 5 , the semiconductor device 40 comprises the n+ type semiconductor substrate 11 . The n− type epitaxial layer 12 is formed on the n+ type semiconductor substrate 11 . The p type diffused base layer 17 is formed on the n− epitaxial layer 12 . The gate trench 13 is formed at the surface of the p type diffused base layer 17 . A plurality of the gate trenches 13 are formed in the X direction. The gate insulator 14 is formed on the sidewall of the gate trench 13 . The polysilicon 15 is formed on the gate insulator 14 . An NSG film 41 is formed on the polysilicon 15 in the gate trench 13 . A dielectric strength of the NSG film 41 is as strong as the CVD oxide film, and the NSG film 41 has a reflowability. Hence, the NSG film 41 is preferable material for an interlayer insulator formed in the gate trench 13 . The HTO film 16 is formed on the NSG film 41 in the gate trench 13 . The CVD oxide film 20 is formed on the HTO film 16 so as to reach the aperture portion of the gate trench 13 . The n+ diffused layer 18 is formed beside the aperture of the gate trench 13 . Next, a manufacturing method of the semiconductor device 40 configured as above is described hereinafter. FIG. 6 shows the first manufacturing process of the semiconductor device 40 . First, the epitaxial layer 12 is formed on the n+ semiconductor substrate 11 by the epitaxial growth. A plurality of the gate trenches 13 are formed in the X direction so that the bottom of the gate trench 13 reaches the epitaxial layer 12 . The gate insulator 14 is formed on an inner aspect of the gate trench 13 . The polysilicon 15 is formed on an inner aspect of the gate insulator 14 . The NSG film 41 is deposited to the polysilicon 15 . Here, the NSG film 41 is formed in the gate trench 13 , and not on the surface 12 a of the epitaxial layer. The HTO film 16 is deposited on the NSG film 41 and the epitaxial layer 12 . At this state, an impurity is implanted to the n− epitaxial layer 12 through the HTO film 16 so that p diffused base layer 17 and the n+ diffused source layer 18 are formed in the n− epitaxial layer 12 . As shown in FIG. 7 , the CVD oxide film 20 is formed on the HTO film 16 . The BPSG film 19 is deposited on the CVD oxide film 20 . As described above, after depositing the BPSG film 19 , the surface of the BPSG film 19 has the ragged asperity along the surface of the BPSG film 19 (not shown). With the high heat processing, the ragged surface of the BPSG film 19 having a reflowability is planarized. An etch-back process is performed to the planarized surface of BPSG film 19 until the surface of CVD oxide film 20 is positioned as high as around the aperture of the gate trench 13 . So, the BPSG film 19 , the CVD oxide film 20 and the HTO film 16 on the epitaxial layer 12 are removed. In this way, the semiconductor device 40 as shown in FIG. 5 is formed. The source electrode 21 and the drain electrode 22 are formed as same as the first embodiment. In the semiconductor device 40 configured as above, as the NSG film 41 is formed between the HTO film 16 and the polysilicon 15 , the gap between the HTO film 16 a on the gate trench 13 and the HTO film 16 b on the surface 12 a of epitaxial layer is less than the first embodiment (see FIG. 6 ). Hence, at the process of forming the p type diffused base layer 17 and the n+ type diffused source layer 18 , it can prevent an impurity from diffusing through the sidewall of the gate trench 13 . As a result, it can prevent the n+ type diffused layer 18 from entering in deeply around the sidewall of the gate trench 13 . So, in the second embodiment, an effect of punch-through phenomena can be reduced more effectively than the first embodiment. Punch-through phenomena become prominent as gate length is shorter. As a result, it can further improve performance of the semiconductor. For the semiconductor device 10 according to the first embodiment as shown in FIG. 1 and the semiconductor device 40 according to the second embodiment, the BPSG film 19 formed in the process of manufacturing is wholly removed by etching. But, this is the case that the thickness of the HTO film 16 and the CVD oxide film 20 are correctly formed and the etch-back process is performed with required accuracy. However, even when the formed BPSG film 19 is not wholly removed, an advantage of this invention to prevent boron and phosphorus from diffusing from the BPSG film 19 can be obtained. FIG. 8 shows a semiconductor device 40 ′ according the second embodiment in the case the BPSG film 19 is not wholly removed. This semiconductor device 40 ′ has the remained BPSG film 19 on the CVD oxide film 20 . In this semiconductor device 40 ′, even if the etch-back process is excessively performed to the NSG film 41 at the manufacturing process of the second embodiment, the thickness of interlayer insulator is enough ensured. Because the CVD oxide 20 , the HTO film 16 , the NSG film 41 , and the BPSG film 19 are layered on the gate trench 13 . Herewith, it can reduce tolerance for etching, and ensure the thickness of the interlayer insulator adequately. As a result, it can diffuse the n+ type diffused source layer 18 to reach the required depth by the heat treatment, and at the time it can restrain diffusing of the impurity. As a result, it can improve performance of UMOSFET having interlayer insulator wholly formed in the gate trench. The case is described that the BPSG film 19 is remained in the second embodiment, but even if the BPSG film 19 may remain in the first embodiment, the advantage of this invention can be obtained also. Material of an oxide film (as the HTO film 16 , the CVD film 20 , the NSG film and the like) is not limited that. A variety of material can be applied to the oxide film. It is apparent that the present invention is not limited to the above embodiments, but may be modified and changed without departing from the scope and spirit of the invention.

A semiconductor device, includes a semiconductor layer of a second conductive type, a first diffused region of a first conductive type formed in the semiconductor layer, a second diffused region of the second conductive type selectively formed in the first diffused region, a trench formed in the semiconductor layer, a polysilicon formed in the trench with an insulator intervening, a first oxide film formed on the polysilicon so that the first oxide film is buried in the trench, a second oxide film formed on the first oxide film so that the second oxide film is buried in the trench, and a flowable insulator film formed on the second oxide film so that the flowable insulator film is buried in the trench.

CROSS-REFERENCE TO RELATED PATENT APPLICATIONS [0001] This application is a Continuation of U.S. application Ser. No. 10/488,790, filed May 4, 2004, which is the National Stage of International Application No. PCT/JP02/08197, filed Aug. 9, 2002, which is based upon and claims the benefit of priority from prior Japanese Patent Application No. 2001-271679, filed Sep. 7, 2001, the entire contents of all of which are incorporated herein by reference. BACKGROUND OF THE INVENTION [0002] 1. Field of the Invention [0003] The present invention relates to an eye optical characteristic measuring apparatus for measuring eye optical characteristics. [0004] 2. Description of the Related Art [0005] Since a Hartmann-Shack wavefront sensor can accurately measure wavefront aberrations of an eye, it has recently attracted considerable attention. This wavefront sensor can become a necessary apparatus in eye surgery in near future especially for the purpose of the planning and follow-up of cornea refractive surgery. [0006] The measurement of the eye wavefront aberrations by the wavefront sensor is greatly different from the measurement of corneal wavefront aberrations by corneal shape measurement in that the measurement result includes an influence of an intraocular optical system, such as a crystalline lens, on the wavefront aberrations. According to this function, it becomes possible to perform an examination in a case where the crystalline lens has refractive index abnormality due to nuclear cataract or the like or in a case where the shape of a refractive plane of the crystalline lens is largely distorted by lenticonus. [0007] As an object of the eye optical system wavefront aberrations measurement, an objective evaluation of visual functions can be named. As the evaluation of the visual functions, a subjective examination has been conventionally recognized as a reliable measurement method as compared with an objective examination. Especially, this is true to such an extent that with respect to an auto-refractometer as a former wavefront sensor, a lens interchange method as the subjective examination is called a gold standard. [0008] When the eye wavefront aberrations measured by the wavefront sensor is compared with corrected eyesight or contrast sensitivity, there is a case where they are fully coincident to each other, and there is a case where they are not coincident to each other especially in, for example, old people. In the case of the inconsistency, there is a case where scattering has a large effect on the eyesight. SUMMARY OF THE INVENTION [0009] As optical factors to influence the visual functions, scattering of an eye optical system, together with the wavefront aberrations, is conceivable. [0010] In the measurement of eye optical characteristics, in the case of aging, cataract, or the like, light scattering from an eye optical system is large, and for the purpose of the objective evaluation of the visual functions, measurement of the light scattering is necessary in addition to the aberrations. An apparatus is desired which enables simultaneous measurement of the light scattering by an optical system of a Hartmann-Shack wavefront sensor which has an established reputation in measurement of the wavefront aberrations. On the other hand, the wavefront aberrations measurement by the Hartmann-Shack wavefront sensor is already in practical use. [0011] In view of the above, the present invention has an object to provide an eye optical characteristic measuring apparatus which can accurately evaluate visual functions by enabling a Hartmann-Shack wavefront sensor, which has a main object of performing wavefront aberrations measurement, to perform light scattering measurement and by performing the light scattering measurement. [0012] Besides, the invention has an object to provide an eye optical characteristic measuring apparatus which enables simultaneous measurement of scattering of the eye by an optical system of the Hartmann-Shack wavefront sensor by developing, as a scattering measurement method by the Hartmann-Shack wavefront sensor, a scattering analytic method for estimating a scattering amount from SIR (Scatter Intensity Ratio) of background light of a Hartmann image. [0013] Besides, the invention has an object to provide an eye optical characteristic measuring apparatus which can measure wavefront aberrations of a light flux incident on a light receiving optical system and a scattering degree of a received light flux from a distribution of relations between the wavefront aberrations of the light flux incident on the light receiving optical system and a point spread function (PSF) of the received light. [0014] Besides, the invention has an object to provide an eye optical characteristic measuring apparatus which can judge that from a distribution of relations between wavefront aberrations of a light flux incident on a light receiving optical system, a scattering degree of a received light flux and a spot diameter of the received light flux, as the wavefront aberrations of the light flux incident on the light receiving optical system and the scattering degree of the received light flux become high, or as the spot diameter of the received light flux becomes large, an influence of cataract or the like becomes large. [0015] In order to achieve the above objects, according to first solving means of the invention, an eye optical characteristic measuring apparatus includes a light source part for emitting a light flux having a specified wavelength, an illumination optical system for illuminating a minute area on a retina of a subject eye with the light flux from the light source part, a light receiving optical system for receiving a part of a reflected light flux of the light flux emitted from the light source part and reflected by the retina of the subject eye through a conversion member for converting it into at least substantially 17 beams, a light receiving part for receiving a received light flux guided by the light receiving optical system to form a signal, and an arithmetic part for obtaining wavefront aberrations of the light flux incident on the light receiving optical system and a scattering degree of the received light flux on the basis of the signal from the light receiving part. [0016] Besides, according to second solving means of the invention, an eye optical characteristic measuring apparatus includes a light source part for emitting a light flux having a specified wavelength, an illumination optical system for illuminating a minute area on a retina of a subject eye with the light flux from the light source part, a light receiving optical system for receiving a part of a reflected light flux of the light flux emitted from the light source part and reflected by the retina of the subject eye through a conversion member for converting it into at least substantially 17 beams, a light receiving part for receiving a received light flux guided by the light receiving optical system to form a signal, and an arithmetic part for obtaining wavefront aberrations of the light flux incident on the light receiving optical system and a spot diameter of the received light flux on the basis of the signal from the light receiving part. [0017] Besides, according to the invention, in the eye optical characteristic measuring apparatus of the first solving means, the arithmetic part can obtain a distribution of relations between the wavefront aberrations of the light flux incident on the light receiving optical system and the scattering degree of the received light flux. Further, according to the invention, in the eye optical characteristic measuring apparatus as stated above, the arithmetic part can be constructed to judge that as the obtained wavefront aberrations of the light flux incident on the light receiving optical system and the scattering degree of the received light flux become high, the influence of cataract or the like becomes large. [0018] Besides, according to the invention, in the eye optical characteristic measuring apparatus of the second solving means, the arithmetic part can obtain a distribution of relations between the wavefront aberrations of the light flux incident on the light receiving optical system and the spot diameter of the received light flux. Further, according to the invention, in the eye optical characteristic measuring apparatus as stated above, the arithmetic part can be constructed to judge that as the obtained wavefront aberrations of the light flux incident on the light receiving optical system and the spot diameter of the received light flux become large, the influence of cataract or the like becomes large. [0019] Besides, according to the invention, in the eye optical characteristic measuring apparatus of the first solving means, the arithmetic part can obtain a distribution of relations among the wavefront aberrations of the light flux incident on the light receiving optical system, the scattering degree of the received light flux, and a spot diameter of the received light flux. Further, according to the invention, in the eye optical characteristic measuring apparatus as stated above, the arithmetic part can be constructed to judge that as the obtained wavefront aberrations of the light flux incident on the light receiving optical system and the scattering degree of the received light flux become high, or the spot diameter of the received light flux becomes large, the influence of the cataract or the like becomes large. [0020] Further, according to the invention, a display part for displaying the distribution obtained by the arithmetic part, the judgment result and the like, or an output part for outputting them to the outside may be included. [0021] Further, according to third solving means of the invention, an eye optical characteristic measuring apparatus includes a light source part for emitting a light flux having a specified wavelength, an illumination optical system for illuminating a minute area on a retina of a subject eye with the light flux from the light source part, a light receiving optical system for receiving a part of a reflected light flux of the light flux emitted from the light source part and reflected by the retina of the subject eye through a conversion member for converting it into at least substantially 17 beams, a light receiving part for receiving a received light flux guided by the light receiving optical system to form a signal, and an arithmetic part for obtaining a point spread function obtained from wavefront aberrations of the light flux incident on the light receiving optical system and an actually measured spot diameter of the received light flux on the basis of the signal from the light receiving part. BRIEF DESCRIPTION OF THE DRAWINGS [0022] FIG. 1 is a view showing a schematic optical system 100 of an eye optical characteristic measuring apparatus of the invention. [0023] FIG. 2 is a structural view of a Placido disk. [0024] FIG. 3 is a block diagram showing a schematic electrical system 200 of the eye optical characteristic measuring apparatus of the invention. [0025] FIG. 4 is a detailed structural view relating to an arithmetic part of the eye optical characteristic measuring apparatus of the invention. [0026] FIG. 5 is a view in which a part of an image received by a first light receiving part 23 is enlarged. [0027] FIG. 6 is an explanatory view for obtaining a point spread function from a wavefront. [0028] FIG. 7 is a view (1) of experimental results according to an eye optical characteristic measuring apparatus of an embodiment. [0029] FIG. 8 is a view (2) of experimental results according to the eye optical characteristic measuring apparatus of the embodiment. [0030] FIG. 9 is an explanatory view showing a picture of point images and point image intensity. DESCRIPTION OF THE PREFERRED EMBODIMENTS [0031] Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. 1. Explanation of Principle of Eye Optical Characteristic Measurement [0032] FIG. 1 is a view roughly showing an optical system 100 of an eye optical characteristic measuring apparatus of the invention. [0033] The optical system 100 of the eye optical characteristic measuring apparatus is an apparatus for measuring, for example, an optical characteristic of an eye 60 to be measured as an object, and includes a first illuminating optical system 10 , a first light receiving optical system 20 , a second light receiving optical system 30 , a common optical system 40 , an adjusting optical system 50 , a second illuminating optical system 70 , and a second light sending optical system 80 . Incidentally, with respect to the eye 60 to be measured, a retina 61 and a cornea 62 are shown in the drawing. [0034] The first illuminating optical system 10 includes, for example, a first light source part 11 for emitting a light flux of a first wavelength, and a condensing lens 12 , and is for illuminating a minute region on the retina (eyeground) 61 of the eye 60 to be measured with the light flux from the first light source part 11 so that its illumination condition can be suitably set. Incidentally, here, as an example, the first wavelength of the illuminating light flux emitted from the first light source part 11 is a wavelength of an infrared range (for example, 780 nm). It is not limited to the wavelength, a illuminating light flux of a specified wavelength can be used. [0035] Besides, it is desirable that the first light source part 11 has a large spatial coherence and a small temporal coherence. Here, the first light source part 11 is, for example, a super luminescence diode (SLD), and a point light source having high luminescence can be obtained. [0036] Incidentally, the first light source part 11 is not limited to the SLD, and for example, a laser having a large spatial coherence and a large temporal coherence can also be used by combining a rotary prism described later. Further, an LED having a small spatial coherence and a small temporal coherence can also be used, if light quantity is sufficient, by inserting, for example, a pinhole or the like at a position of a light source in an optical path. [0037] Besides, in order to uniform the irregular characteristics of reflected light from the retina, a wedge-shaped rotary prism (D prism) 16 is inserted in the illumination optical system. Since an illuminated portion on the retina is operated by the rotation of the rotary prism, the reflected light from the retina becomes uniform, and it is possible to uniform the received light flux (point image) of the light receiving part. [0038] The first light receiving optical system 20 includes, for example, a collimator lens 21 , a Hartmann plate 22 as a conversion member for converting a part of a light flux (first light flux) reflected and returned from the retina 61 of the eye 60 to be measured into at least 17 beams, and a first light receiving part 23 for receiving the plural beams converted by the Hartmann plate 22 , and is for guiding the first light flux to the first light receiving part 23 . Besides, here, a CCD with little readout noise is adopted for the first light receiving part 23 , and as the CCD, a suitable type of CCD, for example, a general low noise type of CCD, a cooling CCD of 1000*1000 elements for measurement, or the like can be applied. [0039] The second illuminating optical system 70 includes a second light source 72 and a Placido's disk 71 . Incidentally, the second light source 72 can be omitted. FIG. 2 shows an example of a structural view of the Placido's disk. The Placido's disk 71 is for projecting an index of a pattern composed of plural co-axial rings. Incidentally, the index of the pattern composed of the plural co-axial rings is an example of an index of a specified pattern, and a different suitable pattern can be used. Then, after an alignment adjustment described later is completed, the index of the pattern composed of the plural co-axial rings can be projected. [0040] The second light sending optical system 80 is for mainly performing, for example, the alignment adjustment described later, and measurement and adjustment of a coordinate origin and a coordinate axis, and includes a second light source part 31 for emitting a light flux of a second wavelength, a condensing lens 32 , and a beam splitter 33 . [0041] The second light receiving optical system 30 includes a condensing lens 34 and a second light receiving part 35 . The second light receiving optical system 30 guides a light flux (second light flux), which is originated from the pattern of the Placido's disk 71 illuminated from the second illuminating optical system 70 and is reflected and returned from the anterior eye part or the cornea 62 of the eye 60 to be measured, to the second light receiving part 35 . Besides, it canal so guide a light flux, which is emitted from the second light source part 31 and is reflected and returned from the cornea 62 of the eye 60 to be measured, to the second light receiving part 35 . Incidentally, as the second wavelength of the light flux emitted from the second light source part 31 , for example, a wavelength different from the first wavelength (here, 780 nm) and longer than that (for example, 940 nm) can be selected. [0042] The common optical system 40 is disposed on an optical axis of the light flux emitted from the first illuminating optical system 10 , can be included in the first and the second illuminating optical systems 10 and 70 , the first and the second light receiving optical systems 20 and 30 , the second light sending optical system 80 and the like in common, and includes, for example, an a focal lens 42 , beam splitters 43 and 45 , and a condensing lens 44 . The beam splitter 43 is formed of such a mirror (for example, a polarization beam splitter) that the wavelength of the second light source part 31 is sent (reflected) to the eye 60 to be measured, the second light flux reflected and returned from the retina 61 of the eye 60 to be measured is reflected, and the wavelength of the first light source part 11 is transmitted. The beam splitter 45 is formed of such a mirror (for example, a dichroic mirror) that the wavelength of the first light source part 11 is sent (reflected) to the eye 60 to be measured, and the first light flux reflected and returned from the retina 61 of the eye 60 to be measured is transmitted. By the beam splitters 43 and 45 , the first and the second light fluxes do not mutually enter the other optical systems to generate noise. [0043] The adjusting optical system 50 is for mainly performing, for example, a working distance adjustment described later, includes a third light source part 51 , a fourth light source part 55 , condensing lenses 52 and 53 , and a third light receiving part 54 , and is for mainly performing the working distance adjustment. [0044] Next, the alignment adjustment will be described. The alignment adjustment is mainly carried out by the second light receiving optical system 30 and the second light sending optical system 80 . [0045] First, the light flux from the second light source part 31 illuminates the eye 60 to be measured as the object with the substantially parallel light flux through the condensing lens 32 , the beam splitters 33 and 43 , and the a focal lens 42 . The reflected light flux reflected by the cornea 62 of the eye 60 to be measured is emitted as a divergent light flux such as is emitted from a point at the half of the radius of curvature of the cornea 62 . The divergence light flux is received as a spot image by the second light receiving part 35 through the a focal lens 42 , the beam splitters 43 and 33 , and the condensing lens 34 . [0046] Here, in the case where the spot image on the second light receiving part 35 deviates from the optical axis, the main body of the eye optical characteristic measuring apparatus is moved and adjusted vertically and horizontally, and the spot image is made to coincide with the optical axis. As stated above, when the spot image coincides with the optical axis, the alignment adjustment is completed. Incidentally, with respect to the alignment adjustment, the cornea 62 of the eye 60 to be measured is illuminated by the third light source 51 , and an image of the eye 60 to be measured obtained by this illumination is formed on the second light receiving part 35 , and accordingly, this image may be used to make the pupil center coincide with the optical axis. [0047] Next, the working distance adjustment will be described. The working distance adjustment is mainly carried out by the adjusting optical system 50 . [0048] First, the working distance adjustment is carried out by, for example, irradiating the eye 60 to be measured with a parallel light flux emitted from the fourth light source part 55 and close to the optical axis, and by receiving the light reflected from the eye 60 to be measured through the condensing lenses 52 and 53 by the third light receiving part 54 . Besides, in the case where the eye 60 to be measured is in a suitable working distance, a spot image from the fourth light source part 55 is formed on the optical axis of the third light receiving part 54 . On the other hand, in the case where the eye 60 to be measured is out of the suitable working distance, the spot image from the fourth light source part 55 is formed above or below the optical axis of the third light receiving part 54 . Incidentally, since the third light receiving part 54 has only to be capable of detecting a change of a light flux position on the plane containing the fourth light source part 55 , the optical axis and the third light receiving part 54 , for example, a one-dimensional CCD arranged on this plane, a position sensing device (PSD) or the like can be applied. [0049] Next, a positional relation between the first illuminating optical system 10 and the first light receiving optical system 20 will be roughly described. [0050] The beam splitter 45 is inserted in the first light receiving optical system 20 , and by this beam splitter 45 , the light from the first illuminating optical system 10 is sent to the eye 60 to be measured, and the reflected light from the eye 60 to be measured is transmitted. The first light receiving part 23 included in the first light receiving optical system 20 receives the light transmitted through the Hartmann plate 22 as the conversion member and generates a received light signal. [0051] Besides, the first light source part 11 and the retina 61 of the subject eye 60 form a conjugated relation. The retina 61 of the subject eye 60 and the first light receiving part 23 are conjugated. Besides, the Hartmann plate 22 and the pupil of the subject eye 60 form a conjugated relation. Further, with respect to the first light receiving optical system 20 , the cornea 62 as the anterior eye part of the subject eye 60 and the pupil, and the Hartmann plate 22 form a substantially conjugated relation. That is, the front focal point of the a focal lens 42 is substantially coincident with the cornea 62 as the anterior eye part of the subject eye 60 and the pupil. Besides, the plane of the rotary prism 16 inclined with respect to the optical axis is disposed at a substantially conjugated position with respect to the pupil. [0052] Besides, the first illuminating optical system 10 and the first light receiving optical system 20 are moved together so that a signal peak by the reflected light at the first light receiving part 23 becomes maximum on the condition that the light flux from the first light source part 11 is reflected at a point on which it is condensed. Specifically, the first illuminating optical system 10 and the first light receiving optical system 20 are moved in a direction in which the signal peak at the first light receiving part 23 becomes large, and are stopped at a position where the signal peak becomes maximum. By this, the light flux from the first light source part 11 is condensed on the eye 60 to be measured. [0053] The lens 12 converts a diffused light of the light source 11 into a parallel light. A diaphragm 14 is positioned at an optically conjugated position with respect to the pupil of the eye or the Hartmann plate 22 . The diaphragm 14 has a diameter smaller than an effective range of the Hartmann plate 22 , and the so-called single path aberrations measurement (method in which the aberrations of the eye has an influence on only the light receiving side) is established. In order to satisfy the above, the lens 13 is disposed such that the conjugated point of the retina of the real light beam coincides with the front focal position, and further, in order to satisfy the conjugated relation between the lens and the pupil of the eye, it is disposed such that the rear focal position coincides with the diaphragm 14 . [0054] Besides, after a light beam 15 comes to have a light path common to a light beam 24 by the beam splitter 45 , it travels in the same way as the light beam 24 paraxially. However, in the single path measurement, the diameters of the light beams are different from each other, and the beam diameter of the light beam 15 is set to be rather small as compared with the light beam 24 . Specifically, the beam diameter of the light beam 15 is, for example, about 1 mm at the pupil position of the eye, and the beam diameter of the light beam 24 can be about 7 mm (incidentally, in the drawing, the light beam 15 from the beam splitter 45 to the retina 61 is omitted). [0055] Next, the Hartmann plate 22 as the conversion member will be described. [0056] The Hartmann plate 22 included in the first light receiving optical system 20 is a wavefront conversion member for converting a reflected light flux into plural beams. Here, plural micro-Fresnel lenses disposed on a plane orthogonal to the optical axis are applied to the Hartmann plate 22 . Besides, in general, with respect to the measuring object part (the eye 60 to be measured), in order to measure a spherical component of the eye 60 to be measured, a third-order astigmatism, and other higher order aberrations, it is necessary to perform the measurement with at least 17 beams through the eye 60 to be measured. [0057] The micro-Fresnel lens is an optical element, and includes, for example, a ring with a height pitch for each wavelength, and a blade optimized for emission parallel to a condensing point. The micro-Fresnel lens here is subjected to, for example, 8-level optical path length variation employing a semiconductor fine working technique, and achieves a high condensing efficiency (for example, 98%). [0058] Besides, the reflected light from the retina 61 of the eye 60 to be measured passes through the a focal lens 42 and the collimate lens 21 , and is condensed on the first light receiving part 23 through the Hartmann plate 22 . Accordingly, the Hartmann plate 22 includes a wavefront conversion member for converting the reflected light flux into at least 17 beams. [0059] FIG. 3 is a block diagram roughly showing an electrical system 200 of the eye optical characteristic measuring apparatus of the invention. The electrical system 200 of the eye optical characteristic measuring apparatus includes, for example, an arithmetic part 210 , a control part 220 , a display part 230 , a memory 240 , a first driving part 250 , and a second driving part 260 . [0060] The arithmetic part 210 receives a received light signal (first signal) ( 4 ) obtained from the first light receiving part 23 , a received light signal (second signal) ( 7 ) obtained from the second light receiving part 35 , and a received light signal ( 10 ) obtained from the third light receiving part 54 , and performs an arithmetical operation on the origin of coordinates, a coordinate axis, movement of coordinates, rotation, ocular aberrations, corneal higher order aberrations, Zernike coefficients, aberration coefficients, a Strehl ratio, a white light MTF, a Landolt's ring pattern and the like. Besides, signals corresponding to such calculation results are outputted to the control part 220 for performing the whole control of an electric driving system, the display part 230 , and the memory 240 , respectively. Incidentally, the details of the arithmetic part 210 will be described later. [0061] The control part 220 controls lighting and lights-out of the first light source part 11 on the basis of the control signal from the arithmetic part 210 , or controls the first driving part 250 and the second driving part 260 . For example, on the basis of the signals corresponding to the operation results in the arithmetic part 210 , the control part outputs a signal ( 1 ) to the first light source part 11 , outputs a signal ( 5 ) to the Placido's disk 71 , outputs a signal ( 6 ) to the second light source part 31 , outputs a signal ( 8 ) to the third light source part 51 , outputs a signal ( 9 ) to the fourth light source part 55 , and outputs signals to the first driving part 250 and the second driving part 260 . [0062] The first driving part 250 is for moving the whole first illuminating optical system 10 in the optical axis direction on the basis of, for example, the received light signal ( 4 ) inputted to the arithmetic part 210 from the first light receiving part 23 , and outputs a signal ( 2 ) to a not-shown suitable lens movement means and drives the lens movement means. By this, the first driving part 250 can perform the movement and adjustment of the first illuminating optical system 10 . [0063] The second driving part 260 is for moving the whole first light receiving optical system 20 in the optical axis direction on the basis of, for example, the received light signal ( 4 ) inputted to the arithmetic part 210 from the first light receiving part 23 , and outputs a signal ( 3 ) to a not-shown suitable lens movement means, and drives the lens movement means. By this, the second driving part 260 can perform the movement and adjustment of the first light receiving optical system 20 . [0064] FIG. 4 is a detailed structural view concerning the arithmetic part of the eye optical characteristic measuring apparatus of the invention. The arithmetic part 210 includes a measurement part 111 , an analysis part 111 ′, a coordinate setting part 112 , an alignment control part 113 , a marker setting part 114 , an input/output part 115 , and a conversion part 116 . [0065] The first light receiving part 23 forms a first received light signal from a received light flux reflected and returned from the retina of the subject eye and guides it to the measurement part 111 . The second light receiving part 35 forms a second received light signal including information of the anterior eye part from the received light flux including information relating to the feature portion of the anterior eye part of the subject eye and/or a marker formed at the anterior eye part of the subject eye, and guides it to the measurement part 111 and the coordinate setting part 112 . [0066] The measurement part 111 obtains the optical characteristics including the refractive power of the subject eye or the corneal formation on the basis of the first received light signal from the first light receiving part. Besides, the measurement part 111 sends the first received light signal to the analysis part 111 ′ for obtaining the spot diameter of the received light flux and the scattering degree of the received light flux. Incidentally, the analysis part 111 ′ may be constructed so as to directly receive the first received light signal from the first light receiving part 23 . The details of the analysis part 111 ′ will be described later. The measurement part 111 performs the eye optical characteristic measurement especially on the basis of the first received light signal from the first light receiving part 23 . Besides, the measurement part 111 performs the cornea topography measurement especially on the basis of the second received light signal from the second light receiving part 35 . Besides, the measurement part 111 performs calculation of aberrations results, and calculation of an aberration amount as the need arises, and outputs the calculation results to a surgical apparatus through the output part 115 . [0067] FIG. 5 is a view in which a part of an image received by the first light receiving part 23 is enlarged. The drawing (A) shows a keratoconic eye, and the drawing (B) shows an example of a Hartmann image in the case of a cataractous eye. The Hartmann image received by the first light receiving part 23 is, for example, the image on the basis of the reflected light from the subject eye, and includes plural area points (circles, ellipses, etc. in the drawing) in the case where the reflected light is received onto the first light receiving part 23 as light fluxes diffused generally outward through the Hartmann plate 22 . An optical signal of the Hartmann image in this example is converted into an electrical signal, and is inputted (or captured) as the first signal to the analysis part 111 ′. [0068] As stated above, the information from the Hartmann-Shack wavefront sensor includes the following. [0069] Wavefront from the barycenter of the point image (classical aberration measurement). [0070] Local information from the blur degree of the point image (local scattering measurement). [0071] Besides, with respect to the eye with much scattering, the blur of an image which can not be explained from only the wavefront aberrations are observed in the Hartmann image. Besides, it is conceivable that the scattering amount is estimated by comparing the Hartmann image obtained by the measurement with the Hartmann image restored from the wavefront aberrations. [0072] The analysis part 111 ′ regards the plural area points as one of the received light fluxes, and obtains the spot diameter of the received light flux and the ratio of the maximum value of the light amount of the received light flux to the minimum value, that is, the scattering degree of the received light flux. The analysis part 111 ′ obtains the distribution indicating the relation between the wavefront aberrations of the light flux incident on the light receiving optical system and the scattering degree of the received light flux. Besides, it obtains the distribution indicating the relation between the wavefront aberrations of the light flux incident on the light receiving optical system and the spot diameter of the received light flux. Incidentally, since the analysis part 111 ′ obtains the distribution concerning the correlation among the wavefront aberrations of the light flux incident on the light receiving optical system, the scattering degree of the received light flux, and the spot diameter of the received light flux, a limitation is not made to the foregoing distribution. [0073] The analysis part 111 ′ obtains the point spread function (PSF) by wave optical calculation from the wavefront aberrations of the light flux incident on the light receiving system, and has a calculation function to compare this with the diameter of the received light flux, that is, the point spread function (PSF) obtained by actually measuring the intensity from the image. For example, there is also a case where a comparison can be made concerning an area at an intermediate value between a maximum value and a minimum value in a square area (length of its side is almost equal to the interval of point images and one point image is generally contained in this area) including the point image, a width or the like. [0074] Incidentally, the foregoing analysis of the analysis part 111 ′ may correspond to plural specified point images of the Hartmann image, and in this condition, as the result of one measurement, the respective point images may be analyzed in the calculation, or an average value of actually measured values may be used. [0075] The analysis part 111 ′ judges that as the obtained scattering degree of the received light flux of the light flux incident on the light receiving optical system as the first light receiving part becomes high, the influence of the cataract or the like becomes large, and can output that to the display part 240 . Besides, the analysis part 111 ′ judges that as the obtained spot diameter of the received light flux in the light receiving optical system as the first light receiving part becomes large, the influence of the cataract or the like becomes large, and can output that to the display part 240 . [0076] Incidentally, the judgment result, analysis result and the like by the analysis part 111 ′ may be displayed in various forms, such as data, table, graph, three-dimensional display and graphic, on the display part 240 , or may be outputted to a recording medium, such as a CD-ROM, a FD or an MO, or another apparatus by the output part. [0077] FIG. 6 is an explanatory view for obtaining the point spread function from the wavefront. [0078] The wavefront of the light flux reflected from the retina of the subject eye passes through the Hartmann plate, and the wavefront aberrations RMS in a lenslet are obtained from the inclination of the light flux at that time, and a factor such as an area of a half-value portion of the point spread function PSF is obtained. [0079] Incidentally, the analysis part 111 ′ can obtain a scattering coefficient in a manner as indicated by a following expression. [0000] Index=√{square root over ( A )}−( a·RMS SL −c )  (1) Index: scattering prediction coefficient (also called scattering prediction index) A: area (average) of the half-value portion of the PSF RMS SL : wavefront aberrations (average) in the lenslet portion [0080] a: constant obtained by non-cataractous eye measurement c: scattering correction constant of measuring apparatus [0081] Incidentally, a and c are coefficients of a regression line obtained in FIG. 7 by using a keratoconic eye and a normal eye. In this case, a: first-order coefficient of 28.894, and c: constant term of 8.6623. [0082] In the actual analysis, there is also a case where the area A is obtained for the plural point images of the Hartmann image, this is subjected to the processing of the above expression and is averaged to obtain the result of one measurement. [0083] This scattering coefficient is obtained for the respective lenslets by using various factors of the respective lenslets. [0084] The relation between the picture of the point image and the point image intensity is as shown in FIG. 9 . At this time, when such a CCD that a gamma value indicating a relation between a light amount and an output becomes 1 is adopted, since the intensity distribution of the PSF is proportional to the digital count (computer count) of the CCD, the measurement is easy. Here, the minimum intensity and the maximum intensity are obtained in a quadrangle 0.6 mm square with the point image as the center, and a Michelson contrast ratio can also be obtained from this, and an area at an intermediate point between the minimum intensity and the maximum intensity can also be obtained. [0085] Besides, a method is also conceivable in which instead of the wavefront aberrations RMS SL , the point spread function (PSF) of FIG. 6 is obtained from the wavefront aberrations by calculation, and this is compared with the actually measured PSF. [0086] In the case where this method is used, it becomes unnecessary to make the correction using the eye with little scattering, such as the normal eye or the keratoconus, and the reliability of the result is increased. On the other hand, in the former method in which the wavefront aberrations and the PSF are compared with each other, since there is no trouble to calculate the PSF by calculation, the total processing time can be made considerably short. [0087] The coordinate setting part 112 converts signals of a first and a second coordinate systems corresponding to the pupil of the subject eye included in the first and the second received light signals into signals of reference coordinate systems, respectively. The coordinate setting part 112 obtains a pupil edge and a pupil center on the basis of the respective signals of the first and the second coordinate systems. [0088] Besides, the coordinate setting part 112 decides the origin of coordinates and the direction of a coordinate axis on the basis of the second received light signal including feature signals of the anterior eye part of the subject eye. Besides, the coordinate setting part 112 obtains the origin of the coordinates, and the rotation and movement of the coordinate axis on the basis of at least one of the feature signals of the anterior eye part of the subject eye of the second received light signal, and correlates the measurement data with the coordinate axis. Incidentally, the feature portion includes at least one of a pupil position, a pupil center, a corneal center, an iris position, an iris pattern, a pupil shape, and a limbus shape. For example, the coordinate setting part 112 sets the origin of the coordinates, such as the pupil center or the corneal center. The coordinate setting part 112 forms the coordinate system on the basis of the feature signal corresponding to the image of the feature portion of the anterior eye part of the subject eye included in the second received light signal. Besides, the coordinate setting part 112 forms the coordinate system on the basis of a marker signal included in the second received light signal and concerning a marker provided on the subject eye, and a signal concerning the anterior eye part of the subject eye. The coordinate setting part 112 can decide the origin of the coordinates and the direction of the coordinate axis on the basis of the second received light signal including the marker signal. The coordinate setting part 112 obtains the origin of the coordinates on the basis of the marker signal in the second received light signal, obtains the rotation and movement of the coordinate axis on the basis of any one of the feature signals of the anterior eye part of the subject eye in the second received light signal, and can correlate the measurement data with the coordinate axis. Alternatively, the coordinate setting part 112 obtains the origin of the coordinates on the basis of at least one of the feature signals concerning the anterior eye part in the second received light signal, obtains the rotation and movement of the coordinate axis on the basis of the marker signal in the second received light signal, and may correlate the measurement data with the coordinate axis. Alternatively, the coordinate setting part 112 obtains the origin of the coordinates and the rotation and movement of the coordinate axis on the basis of at least one of the feature signals of the anterior eye part of the subject eye in the second received light signal, and may correlate the measurement data with the coordinate axis. [0089] The conversion part 116 correlates the first and the second optical characteristics of the subject eye obtained by the measurement part 111 through the respective reference coordinate systems formed by the coordinate setting part and combines them. Besides, the conversion part 116 performs conversion to the reference coordinate system by making the pupil center obtained by the coordinate setting part 112 the origin. [0090] One of, two or more of, or all of the first illuminating optical system 10 , the first light receiving optical system 20 , the second light receiving optical system 30 , the common optical system 40 , the adjusting optical system 50 , the second illuminating optical system 70 , and the second light sending optical system 80 are suitably provided in an alignment part of the optical system 100 . The alignment control part 113 can move this alignment part according to the movement of the subject eye and in accordance with the operation result of the coordinate setting part 112 on the basis of the second received light signal obtained by the second light receiving part. On the basis of the coordinate system set by the coordinate setting part 112 , the marker setting part 114 forms a marker correlated with the coordinate system on the anterior eye part of the subject eye. The input/output part 115 is an interface for outputting data and operation results of the aberration amount, the origin of coordinates, the coordinate axis, the rotation and movement of the coordinate axis, and the ablation amount to the surgical apparatus. A display part 240 displays the optical characteristic of the subject eye obtained by the measurement part 111 in relation to the coordinate system formed by the coordinate setting part. [0091] A surgical apparatus 300 includes a surgical control part 121 , a working part 122 , and a memory part 123 . The surgical control part 121 controls the working part 122 , and controls a surgical operation such as corneal refractive surgery. The working part 122 includes a laser for the surgical operation such as corneal refractive surgery. The surgical memory part 123 stores data for the surgical operation, such as data concerning cutting, a nomogram, a surgical schedule and the like. [0092] Next, FIG. 7 shows a view (1) of experimental results by the eye optical characteristic measuring apparatus of this embodiment. In this embodiment, for the confirmation of measurement of eye optical characteristics, 9 normal eyes, 24 keratoconic eyes, and 17 cataractous eyes were measured, and the half-value widths were obtained. Incidentally, in the drawing, the normal eye (normal) is indicated by rhombus (♦), the keratoconic eye (keratoconus) is indicated by square (▪), and the cataractous eye (cataract) is indicated by triangle (▴). [0093] The measurement part 111 or the analysis part 111 ′ analyses the output result from the first received light signal ( 4 ) by a specified analytic method. That is, the blur of the received laser light is considered to be the scattered light, and there is obtained the half-value width (square root of area for apots) on the basis of the size of the spot diameter of the received light flux or the ratio of the maximum received light amount of the received light flux to the minimum received light amount, that is, the scatter intensity ratio (minimum intensity/maximum intensity, scattering coefficient) is obtained. Besides, the measurement part 111 or the analysis part 111 ′ prepares the distribution ( FIG. 6 ) of the spot diameter of the received light flux or the distribution of the scatter intensity ratio of the received light flux with respect to the phase (standard deviation) of the wavefront aberrations incident on the first light receiving part 23 , which are obtained by the light receiving optical system. [0094] Incidentally, with respect to the cataractous eye, since it deviates from the approximated straight line, it can be differentiated from the keratoconic eye. That is, on the basis of the obtained straight line approximation, a test subject who is suspected of having the cataractous eye is discriminated, and this can be used as information for making a decision about the surgery and remedy. [0095] FIG. 8 shows a view (2) of experimental results by the eye optical characteristic measuring apparatus of this embodiment. [0096] In this drawing, the correction by eq. (1) is added to the half-value width of FIG. 7 . The vertical axis indicates an amount obtained by subtracting a value obtained by substituting the wavefront aberrations of the lenslet into eq. (1) from the half-value width. In non-cataractous eyes, obtained values are arranged substantially horizontally. In the cataractous eye or an eye with large scattering, this value becomes large. Besides, a model eye whose scattering can be neglected is measured, and it is also conceivable that a correction is further performed by this measurement value to make the estimate of the scattering amount more accurate. Although the method used here is suitable for the measurement of the crystalline lens scattering, it is also conceivable to apply this to measurement of retina scattering or the like. [0097] As the result of the analysis, as an example, there were obtained SIR (scatter intensity ratio)=0.460±0.067 for the normal eye, SIR=0.495±0.098 for the keratoconic eye, and SIR=0.667±0.148 for the cataractous eye (ANOVA (dispersion analysis), P<0.01). Besides, the scattering coefficient was 2.61±0.70 for the normal eye, 3.38±2.73 for the keratoconic eye, and 10.13±7.25 for the cataractous eye. Besides, although there was no significant difference between the normal eye and the keratoconic eye (P<0.122), there was significant difference between the normal eye and the cataractous eye, and between the keratoconic eye and the cataractous eye (P<0.01). Incidentally, in order to confirm the effectiveness of the analytic method, 9 normal eyes with little scattering, 24 keratoconic eyes, and 17 cataractous eyes with large scattering were measured. [0098] By this, possibility of measurement of the scattering amount by the Hartmann-Shack wavefront sensor is suggested. After this, evaluation standards comparable to visual functions are examined, and clinical effectiveness is confirmed. INDUSTRIAL APPLICABILITY [0099] According to the present invention, it is possible to provide the eye optical characteristic measuring apparatus which enables the scattering measurement by the Hartmann-Shack wavefront sensor whose main object is wavefront aberration measurement, and can accurately estimate the visual functions by performing the scattering measurement. [0100] Besides, according to the invention, as the scattering measurement method by the Hartmann-Shack wavefront sensor, the scattering analytic method is developed in which the scattering amount is estimated from the scatter intensity ratio (SIR) of background light of the Hartmann image, and the eye optical characteristic measuring apparatus which can enable simultaneous measurement of scattering by the optical system of the Hartmann-Shack wavefront sensor can be provided. [0101] Besides, according to the invention, the eye optical characteristic measuring apparatus can be provided which can make the judgment that from the distribution of relations between the wavefront aberrations of the light flux incident on the light receiving optical system and the scattering degree of the received light flux, as the wavefront aberrations of the light flux incident on the light receiving optical system and the scattering degree of the received light flux become high, the influence of the cataract becomes large. [0102] Besides, according to the invention, the eye optical characteristic measuring apparatus can be provided which can make the judgment that from the distribution of relations among the wavefront aberrations of the light flux incident on the light receiving optical system, the scattering degree of the received light flux, and the spot diameter of the received light flux, as the wavefront aberrations of the light flux incident on the light receiving optical system and the scattering degree of the received light flux become high, or as the spot diameter of the received light flux becomes large, the influence of the cataract becomes large.

Scattering can be measured by using an optical system having a Hartman-Shack wave-surface sensor. An eye optical characteristic measuring instrument comprises a light source unit 10 for emitting a light beam of a wavelength in the near-infrared region, an illumination optical system 40 for illuminating a small area of the retinal of an eye to be measured with the light beam from the light source unit 10 , a light-receiving optical system 20 for receiving a part of the reflected beam of the light beam from the light source unit 10 reflected from the retina through a converting member for converting the part of the reflected light beam into at least substantially 17 light beams, a light-receiving section 23 for receiving the received light beam directed by the light-receiving optical system 20 and generating a signal, and a calculating unit for determining the wavefront aberration of the light beam entering the light-receiving optical system 20 and the degree of scattering of the received light beam on the basis of the signal from the light-receiving section 23.

BACKGROUND OF THE INVENTION U.S. Pat. No. 3,753,179, assigned to the assignee of this application, discloses a keyboard switch containing reed switches oriented vertically. As a result, the height of the keyboard switch is substantial and requires additional wire to be welded to the leads of the reed switches. U.S. Pat. No. 4,346,360 to Del Tufo discloses orienting a reed switch horizontally, thereby reducing the height and avoiding the welding step. However, structure in the Del Tufo patent used to mount the reed switches has shortcomings. SUMMARY OF THE INVENTION It is therefore an important object of the present invention to horizontally mount magnetically actuated switches in a keyboard switch in an improved way. Another object is to provide structure to interlock a plurality of keyboard switches. In summary, there is provided a keyboard switch for mounting on a PC board comprising a housing, a base plate and a cover plate interconnected in stacked relationship and mounted on the housing, at least one of the plates having an elongated cavity therein, a plunger slidably carried by the housing and movable in first and second predetermined directions respectively toward and away from the plates, magnet means carried by the plunger and movable therewith, means biasing the plunger in one of the predetermined directions, an elongated magnetically actuated switch in the elongated cavity and having opened and closed positions, the elongated magnetically actuated switch being opened in response to movement of the plunger in one of the predetermined directions and being closed in response to movement of the plunger in the other of the predetermined directions. The invention consists of certain novel features and a combination of parts hereinafter fully described, illustrated in the accompanying drawings, and particularly pointed out in the appended claims, it being understood that various changes in the details may be made without departing from the spirit, or sacrificing any of the advantages of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS For the purpose of facilitating an understanding of the invention, there is illustrated in the accompanying drawings a preferred embodiment thereof, from an inspection of which, when considered in connection with the following description, the invention, its construction and operation, and many of its advantages should be readily understood and appreciated. FIG. 1 is an elevational view of a keyboard switch incorporating the features of the present invention, mounted on a PC board; FIG. 2 is an elevational view of the keyboard switch rotated 90° with respect to FIG. 1; FIG. 3 is a view in horizontal section taken along the line 3--3 of FIG. 1, on an enlarged scale; FIG. 4 is an exploded view of the keyboard switch; FIG. 5A is an elevational view of the base plate in the keyboard switch; FIG. 5B is an elevational view of the base plate rotated 90° with respect to FIG. 5A; FIG. 6 is a top plan view of the base plate; FIG. 7 is an elevational view of the cover plate in the keyboard switch; FIG. 8 is a top plan view of the cover plate; FIG. 9 is a bottom plan view of the cover plate; FIG. 10 is a fragmentary view in vertical section taken along the line 10--10 of FIG. 1, on an enlarged scale; FIG. 11 is a view in vertical section taken along the line 11--11 of FIG. 1, on an enlarged scale; FIG. 12 is a view of four keyboard switches assembled together; FIG. 13 is a view of six keyboard switches assembled together; and FIG. 14 is a view of three keyboard switches and two spacers assembled together. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Turning now to the drawings, there is depicted a keyboard switch 20 which incorporates the features of the present invention. It is mounted on a PC board 25. The keyboard switch 20 comprises a hollow housing 30 which is generally square in transverse cross section and includes two opposite side walls 31, two opposite side walls 32 and an end wall 33. A relatively large, central hole 34 is in the end wall 33. Respectively in the side walls 31, adjacent to their free ends, are two generally square apertures 35. In one of the side walls 31 and in one of the side walls 32 are dovetail grooves 36. On the other of the side walls 31 and on the other of the side walls 32 are dovetail tongues 37. The keyboard switch 20 further comprises a base plate 40 best seen in FIGS. 5A, 5B and 6. The base plate 40 is generally square in plan, having two opposite sides 41 and two opposite sides 42. The base plate 40 has an upper surface 43 and a lower surface 44 which are parallel. Located in the upper surface 43 near the sides 41 thereof are two elongated cavities 45 and 46 which are generally semicircular in transverse cross section. A lug 47 is on each side wall 41 and is upstanding with respect to the surface 43. Each lug 47 has a camming surface 48 and a locking surface 49. An upstanding peg 50 is on the surface 43 and two depending pegs 51 are on the lower surface 44. The upper surface 43 has a groove 52 generally parallel to the cavities 45 and 46, but nearer the cavity 45. Finally, the base plate 40 includes two holes 53 which, in the embodiment shown, lie on a line parallel to the cavities 45 and 46. The keyboard switch 20 further comprises a cover plate 60 best seen in FIGS. 7-9. The cover plate is generally square in cross section having two opposite sides 61 and two opposite sides 62. The cover plate 60 has an upper surface 63 and a lower surface 64 which are parallel. Located in the lower surface 64 near the sides 61 thereof are two elongated cavities 65 and 66 which are generally semicircular in transverse cross section. Located generally centrally on the surface 63 and upstanding therefrom is a generally hollow post 67 having a wall 68 transversely therein. The sides of the wall may be flared as shown, leading to two holes 69 through the cover plate 60. The distance between the holes 69 matches the distance between the holes 53 in the base plate 40. The keyboard switch 20 comprises a pair of receptacles 70, each having a lead 71. Each receptacle 70 has a reduced-diameter body portion, which portions respectively frictionally fit into the holes 53 in the base plate 40. The leads 71 extend away from the lower surface 44. The keyboard switch 20 further comprises an elongated reed switch 75 of well-known construction. Generally, it consists of an elongated glass envelope which is hermetically sealed and contains an inert gas. In the envelope is a pair of beams which are thin, narrow metal strips that are directed toward one another. At the inner ends of the beams are contacts which are spaced from each other, so that the contacts are normally open. Leads 76 connected to the beams extend out of the glass envelope. When the contacts are oppositely magnetically poled so as to be attracted to each other, they will close. This occurs when they are exposed to a magnetic field with sufficient magnitude to overcome the rigidity of the beams. The keyboard switch 20 further comprises a second reed switch 77 having leads 78 and is identical to the reed switch 75. The base plate 40 and the cover plate 60 are interconnected in stacked relationship, with the surface 43 of the base plate 40 in contact with the surface 64 of the cover plate 60. The cavities 45 and 65 are aligned, thereby creating a composite cavity in which the reed switch 75 is located. Similarly, the cavities 46 and 66 are aligned, thereby creating a composite cavity in which the reed switch 77 is located. The leads 76 of the reed switch 75 are disposed in grooves 46a respectively at the ends of the cavity 46, while the leads 78 of the reed switch 77 are disposed in grooves 45a at the ends of the cavity 45. The leads are bent downwardly so as to depend from the base plate 40. The peg 50 fits into the hole 69a to help to prevent relative movement of the plates 40 and 60. The keyboard switch 20 further comprises a U-shaped clip 80 including a bight 81 and two depending legs 82. The bight 81 is located in the groove 52 of the base plate 40, and the legs 82 depend from the surface 44 of the base plate 40. Each of the legs 82 has a bent portion 83 for springingly engaging holes in the PC board 25. During factory assembly, the reed switches 75 and 77 are respectively placed in the cavities 45 and 46 of the base plate 40 and the leads 76 and 78 bent as explained above. The clip 80 is placed in the groove 52 also as explained above. Then, the cover plate 60 is positioned above the plate 40 and the plates 40 and 60 are brought together, the cover plate 60 being located between the lugs 47. The spacing between the lugs 47 substantially matches the distance between the wall side 61, thereby causing the plates 40 and 60 to become frictionally secured together. No additional means of attachment is required. The reed switches 75 and 77 are firmly held in place, again, without any additional means of attachment. Then, the subassembly consisting of the plates 40 and 60 is mounted on the housing 30. The subassembly is aligned with the end of the housing 30 opposite the end wall 33. The sides 41 are respectively aligned with the side walls 31, and the sides 42 are respectively aligned with the side walls 32. During assembly, the camming surfaces 48 engage the free ends of the side walls 31 causing them to separate slightly. The plate subassembly is forced onto the housing, causes the lugs 47 respectively to snap into the apertures 35. The locking surfaces 49 preclude retrograde movement of the plate subassembly, thereby firmly connecting the plate subassembly with the housing 30. The keyboard switch 20 further comprises a plunger 90 including a body 91 which is generally square in plan. A neck 92 extends from an abutment surface 94 at one end of the body 91. A hole 93 extends through the body 91 and the neck 92. The external side-to-side dimensions of the body 91 are slightly smaller than the internal side-to-side dimensions of the housing 30. The neck 92 has four notches 95 to enable slight deformation of the neck when a cap is applied, as will be described. Within the hole 93 is a ledge 96. Extending through the body 91, adjacent to the four corners thereof, are four holes 97, two of which frictionally retain cylindrical magnets 98 and two of which frictionally retain cylindrical magnets 99. Prior to mounting the plate subassembly, the plunger 90 is inserted into the housing 30. The neck 92 protrudes through the hole 34 in the housing 30, and the abutment surface 94 engages the end wall 33 of the housing 30. A spring 100 is positioned such that one end is within the hole 93 of the plunger 90 and against the ledge 96. The other end of the spring 100 encircles the post 67 on the cover plate 60. Then, the subassembly, including the base plate 40, the cover plate 60 and the elements contained therein, is mounted to the housing as described above. The spring biases the plunger 90 away from the plates 40 and 60. The magnets 98 are normally displaced from the reed switches 75 and 77, which are, therefore, normally open. The magnets 98 are respectively aligned with the ends of the reed switch 75 and the magnets 99 are respectively aligned with the ends of the reed switch 77. The benefits and mode of operation of two smaller magnets to operate a reed switch are described in detail in the above-mentioned U.S. Pat. No. 3,753,179. Suffice it to say that when the magnetic fields created by the magnets 98 and 99 close the reed switches 75 and 77, respectively, when the plunger 90 is depressed. The keyboard switch 20 also comprises a lamp 105, the leads 106 of which are frictionally fit into the receptacles 70. Finally, a cap 110 is provided having a depending tubular portion 111 which frictionally is located in the neck 92. The keyboard switch 20 can be mounted to a PC board. The pegs 51 are placed into holes in the PC board to preclude swiveling of the switch. The leads 76 and 78 of the reed switches extend into holes as do the leads 71 of the receptacles. Suitable electrical connection is made to these leads. The legs 82 of the clip 80 fit into holes in the PC board and the spring portions 83 springingly engage such holes to assist in firmly retaining the switch 20 on the PC board. Although the particular embodiment depicted includes a lamp and two reed switches, there are applications in which the lamp can be omitted and/or one of the reed switches can be omitted. Several keyboard switches 20 may be secured together as depicted in FIGS. 12 or 13 utilizing the dovetail grooves 36 and the dovetail tongues 37 on the housing 30. A spacer 120 is elongated and has two substantially parallel side walls 121. One of the walls carries a dovetail tongue and the other of the walls has a dovetail groove therein. The spacer 120 can be used in assembling keyboard switches 20 in a line as depicted in FIG. 14 to space two keyboard switches 20 from each other. In the foregoing, switches 75 and 77 are described and depicted as reed switches. However, it is to be understood that these switches can be other magnetically actuated switches, such as those incorporating Hall effect devices. Also, in the particular embodiment depicted, the keyboard switch and its basic elements are square in transverse cross section. They could be rectangular. Also, the reed switches have been described as being normally open, and closed when the cap is depressed. These switches could be normally closed. Finally, although the keyboard switch has been described as single pole, single throw, it could be a single pole, double throw switch. While there has been described what is at present considered to be the preferred embodiment of the invention, it is to be understood that changes can be made therein without departing from the true spirit and scope of the claims.

The switch comprises a square, hollow housing. A base plate and a cover plate are snap fitted in stacked relationship. First and second elongated cavities in the base plate are respectively aligned with first and second cavities in the cover plate and within these aligned cavities are respectively located two elongated reed switches. A plunger is slidably carried by the housing and movable toward and away from the plates. The plunger carries two pairs of magnets respectively aligned with the reed switches. When the plunger is depressed, the magnets move into close proximity with the reed switches, closing them. A spring biases the plunger away from the reed switches, whereby the reed switches are normally open.

CROSS-REFERENCES TO RELATED APPLICATIONS [0001] This application is a continuation of PCT/EP2010/052967, filed on Mar. 9, 2010, which claims priority under 35 U.S.C. §119 to DE 10 2009 001 693.7 filed on Mar. 20, 2009, and DE 10 2009 001 803.4 filed on Mar. 24, 2009. FIELD OF THE INVENTION [0002] The present invention generally relates to the use of polymers with carboxyl groups in combination with divalent cations for forming a protective layer on textile fabrics as well as textile treatment agents, in particular washing and cleaning agents that comprise such polymers in a suitable dosage form, in order to enable the formation of a protective layer on textile fabrics. BACKGROUND OF THE INVENTION [0003] In addition to the wish to remove stains from textiles in the most effective possible manner, there exists a further approach for the provision of clean laundry consisting in preventatively impeding a soil deposition on the textiles. Polymers that possess soil repellent properties, the so-called “soil release” or “soil repellency” polymers, have already been described for this purpose. [0004] With this in mind, U.S. Pat. No. 4,007,305 in particular discloses the finishing of textiles with an alkaline aqueous solution that contains fluorinated chemicals, water-soluble polyvinyl pyrrolidone and polymers with carboxyl groups. [0005] The use of substituted polysaccharides for equipping textiles is disclosed in WO 03/040279. BRIEF SUMMARY OF THE INVENTION [0006] According to the present invention, it has now been surprisingly found that an effective protective layer can be formed on textile fabrics by employing polymers with carboxyl groups in combination with divalent cations. [0007] Accordingly, the present invention relates to textile treatment agents, in particular washing and cleaning agents that comprise polymers with carboxyl groups and divalent cations. In this regard an inventive textile treatment agent preferably comprises [0008] a) polymers with carboxyl groups in a concentration of 1 to 10 wt. %, particularly preferably 2 to 4 wt. %, [0009] b) divalent cations in a concentration of 0.001 to 1.0 wt. %, particularly preferably 0.005 to 0.5 wt. %, above all 0.01 to 0.1 wt. %. [0010] Accordingly, the present invention further relates to the use of polymers with carboxyl groups in combination with divalent cations or the use of an inventive textile treatment agent for finishing textile fabrics. [0011] Furthermore, the present invention relates to the use of polymers with carboxyl groups in combination with divalent cations or the use of an inventive textile treatment agent for forming a protective layer on textile fabrics. In this regard the protective layer is preferably suitable for at least partially keeping soils away from textile fabrics in that the soils are preferably deposited on the protective layer rather than on the fabrics. [0012] The present invention also relates to a process for finishing textile fabrics, wherein the textile fabrics are treated with a combination of polymers with carboxyl groups and of divalent cations or with an inventive textile treatment agent, wherein this treatment can both be carried out in one step as well as in sequential process steps. Thus the treatment with the polymers can occur first and then the treatment with the divalent cations or conversely, first the treatment with the divalent cations and then the treatment with the polymers. However, in a preferred embodiment the treatment occurs simultaneously with the polymers and with the divalent cations. [0013] Furthermore, other desirable features and characteristics of the present invention will become apparent from the subsequent detailed description of the invention and the appended claims. DETAILED DESCRIPTION OF THE INVENTION [0014] The following detailed description of the invention is merely exemplary in nature and is not intended to limit the invention or the application and uses of the invention. Furthermore, there is no intention to be bound by any theory presented in the preceding background of the invention or the following detailed description of the invention. [0015] In particular, the polymer with carboxyl groups of the present invention can be obtained by polymerizing monomers that carry ethylenically unsaturated carboxyl groups. Thus it can be a polymer that is obtained by polymerizing or copolymerizing acrylic acid, methacrylic acid or alkyleneterephthalic acids, in particular ethyleneterephthalic acid. With this in mind, polyacrylic acid or polymethacrylic acid are especially inventively employable. [0016] However, in a preferred embodiment the polymer with carboxyl groups is a polysaccharide that contains sugar units that carry carboxyl groups. In this regard the sugar units that carry carboxyl groups are preferably uronic acids, in particular hexuronic acids, principally glucuronic acid, galacturonic acid, iduronic acid or mannuronic acid. Besides uronic acids however, sugar units that are modified for example by carboxyl groups or carboxymethyl groups also come into consideration, such as for example carboxymethyl glucose. [0017] In a preferred embodiment, at least 20%, in particular at least 30, 40 or 50%, particularly preferably at least 60, 70 or 80%, above all at least 90 or 95% of the monomer units of the polymer possess at least one carboxyl group, preferably one, two or three carboxyl groups. [0018] In a preferred embodiment, the polymer is correspondingly a polysaccharide, in which at least 20%, in particular at least 30, 40 or 50%, particularly preferably at least 60, 70 or 80%, above all at least 90 or 95% of the monomer units of the polysaccharide represent uronic acids, in particular hexuronic acid, wherein the uronic acids are preferably selected from glucuronic acid, galacturonic acid, guluronic acid, iduronic acid and mannuronic acid. [0019] In addition, the molecular weight of the polymer with carboxyl groups is preferably from 1000 to 500 000 g/mol, particularly preferably from 10 000 to 200 000 g/mol. [0020] The carboxyl groups of the polymers according to the invention can also be partially esterified with alcohols, in particular with C 1-6 alkanols. [0021] In a particularly preferred embodiment, the polymer with carboxyl groups is selected from the polysaccharides alginate, pectin, glucosaminoglucans, in particular hyaluronic acid or heparin, astragalus, gum arabicum, teichuronic acids and carboxymethyl cellulose, wherein alginate and pectin are particularly preferred. [0022] In a preferred embodiment, the inventively employed polymer is used in the form of a water-soluble salt, in particular as the sodium, potassium or ammonium salt. [0023] The polymer with carboxyl groups is preferably inventively employed in an amount of 1 to 10 wt. %, particularly preferably 2 to 4 wt. %. [0024] The divalent cations are inventively preferably selected from Ca(II), Mg(II), Fe(II) and Zn(II). Ca(II) is particularly preferably employed. [0025] The divalent cations can be employed in any soluble salt form, in particular in the form of an inorganic or organic salt. Halides, in particular fluorides, chlorides or bromides, nitrates or sulfates are preferably employed. [0026] The divalent cations are inventively preferably employed in an amount of 0.001 to 1.0 wt. %, particularly in an amount of 0.005 to 0.5 wt. %, particularly preferably in an amount of 0.01 to 0.1 wt. %. [0027] The textile finishing or the washing process is preferably done at a temperature of 20 to 60° C., particularly preferably at a temperature of 20 to 40° C. [0028] The textile finishing or the washing process is preferably done at a pH of 6 to 11, particularly preferably at a pH of 7.5 to 9.5. [0029] The textile treatment agent according to the invention can exist in any dosage form. For example, it can be in the form of a powder, a liquid or a gel. In a preferred embodiment it is in the form of a liquid or has the consistency of a gel. The polymers with carboxyl groups as well as the divalent cations are preferably present in the liquid or gel-like textile treatment agent in soluble form. [0030] In a particularly preferred embodiment the inventive textile treatment agent is a washing or cleaning agent. Washing and Cleaning Agents [0031] An inventive washing or cleaning agent and in particular an inventive textile washing agent can comprise additional active washing or cleaning ingredients, for example surfactants especially anionic, non-ionic, cationic and/or amphoteric surfactants, builders, especially inorganic and organic builders, active cleaning polymers (for example those with cobuilder properties), foam inhibitors, colorants, fragrances (perfumes), bleaching agents (such as for example peroxy bleaching agents and chlorine bleaching agents), bleach activators, bleach stabilizers, bleach catalysts, enzymes, enzyme stabilizers, anti-graying inhibitors, optical brighteners, UV absorbers, soil repellents or soil release polymers, binding and disintegration auxiliaries, electrolytes, non-aqueous solvents, pH adjustors, perfume carriers, fluorescent agents, thickeners, hydrotropes, silicone oils, shrink preventers, anti-crease agents, color transfer inhibitors, antimicrobials, germicides, fungicides, antioxidants, preservatives, corrosion inhibitors, antistats, bittering agents, ironing auxiliaries, waterproofing and impregnation agents, swelling and anti-slip agents, textile softening components, especially esterquats, heavy metal complexing agents, abrasives, fillers and/or blowing agents. [0032] In regard to inventively preferred employable builders, surfactants, fabric softening components, especially esterquats, polymers, bleaching agent, bleach activators, bleach catalysts, solvents, thickeners, optical brighteners, anti-graying agents, anti-crease agents, antistats, glass corrosion inhibitors, corrosion inhibitors, “soil repellents”, color transfer inhibitors, foam inhibitors, abrasives, disintegration auxiliaries, acidifiers, colorants, fragrances, antimicrobials, UV absorbers and blowing agents as well as their preferred added amounts, reference is made to the laid open publications WO2008/107346 and WO2009/071451. [0033] Processes for cleaning textiles, in which a combination of polymers with carboxyl groups and of divalent cations are employed in at least one of the process steps, represent a separate subject matter of the invention. [0034] These processes include both manual as well as automatic processes, automatic processes being preferred due to their more precise controllability that concerns for example the added quantities and contact times, [0035] Processes for the cleaning of fabrics are generally characterized in that various cleaning-active substances are applied to the material to be cleaned in a plurality of process steps and, after the contact time, are washed away, or that the material to be cleaned is treated in any other way with a washing agent or a solution of this agent. It is possible to add a combination of polymers with carboxyl groups and of divalent cations in at least one of the process steps of all conceivable washing or cleaning processes; these processes then illustrate embodiments of the present invention. [0036] The use of a combination of polymers with carboxyl groups and of divalent cations for cleaning textiles represents a separate subject matter of the invention. Washing by hand or the manual removal of blemishes from textiles or from hard surfaces or the use in connection with an automatic process are exemplary embodiments. [0037] Another subject matter of the present invention is also a product comprising an inventive composition or an inventive textile treatment agent, in particular washing or cleaning agents, and a spray dispenser. In this regard, the product can be either a single chamber container as well as a multi-chamber container, in particular a two-chamber container. The preferred spray dispenser is a manually operated spray dispenser, selected in particular from the group including aerosol spray dispensers pressurized gas containers; also known inter alia as spray cans), self-generated pressure spray dispensers, pump spray dispensers and trigger spray dispensers, particularly pump spray dispensers and trigger spray dispensers with a container made of transparent polyethylene or polyethylene terephthalate. Spray dispensers are extensively described in WO 96/04940 (Proctor & Gamble) and in the U.S. patents cited therein concerning spray dispensers, all of which are referred to in this respect and their content is hereby incorporated in this application. Trigger spray dispensers and pump spray dispensers are advantageous in comparison with pressurized gas containers as no propellant need be employed. By means of attachments suitable for particles, (“nozzle-valves”) on the spray dispenser, the optionally comprised enzyme in this embodiment can also be optionally added in the form of immobilized particles to the composition and can thus be dosed as the cleaning foam. [0038] Particularly preferred textile treatment agents contain 1 to 20 wt. %, preferably 3 to 15 wt % and especially 5 to 12 wt. % of non-ionic, surfactants, in particular fatty alcohol ethoxylates; 1 to 20 wt. %, preferably 3 to 15 wt. % and especially 5 to 12 wt. % of anionic surfactants, in particular from the group of the sulfates or sulfonates, especially linear alkylbenzene sulfonates; 0.5 to 10 wt. %, preferably 1 to 8 wt. % and especially 2 to 6 wt. % of fatty acids; 0.1 to 8 wt. %, preferably 0.5 to 6 wt. % and especially 1 to 5 wt. % of organic acids, in particular polycarboxylic acids and especially citric acid; 0.1 to 5 wt. %, preferably 0.2 to 4 wt. % and especially 0.5 to 3 wt. % of enzyme(s), preferably selected from amylases and proteases; 0.1 to 10 wt. %, preferably 1 to 10 wt. % and especially 2 to 4 wt. % of polymers with carboxyl groups, especially polysaccharides with carboxyl groups, especially alginate or pectin; as well as 0.001 to 1.0 wt. %, preferably 0.005 to 0.5 wt. % and especially 0.01 to 0.1 wt. % of divalent cations, especially Ca(II), preferably in the form of an organic or inorganic salt. EXAMPLES Example 1 Washing Tests with Alginate and Calcium Ions [0046] A washing agent composition comprising: [0000] Fatty alcohol polyethylene oxide 7.0% LAS 9.0% Coconut fatty acid 4.0% Boric acid 1.0% Citric acid 2.0% Propylene glycol 6.0% PTPMP 0.2% NaOH 3.1% Protease 0.8% Amylase 0.1% Water remainder was mixed on the one hand with 2 wt. % of alginate (Texamid 558 P from Cognis), on the other hand with 2 wt. % of alginate and 0.15 wt. % of CaCl 2 . Textiles made of pure cotton were then washed with these washing agent compositions as well as with a washing agent composition as a comparison without added alginate and CaCl 2 . [0047] A washing machine Miele W 918 Novotronic was used for the washing tests. 3.5 kg of clean washing was washed with the standard program with a simple wash cycle at 40° C. using water with a German hardness of 16°. The liquid volume was 18 liters. In order to obtain a statistical mean, 5 parallel wash tests were each carried out. [0048] The clean textiles were each washed three times under the abovementioned conditions each with 100 g of the previously cited washing agent composition. After the third cycle the textiles were soiled with engine oil. The intensity of the soils was recorded with a Minolta camera CR 200 and then left at room temperature for 7 days. The aged soils were then washed again under the previously cited conditions, then allowed to dry and the intensity values of the soils were again determined with the Minolta camera CR 200. [0049] The differences in the intensity values are listed below and were obtained from the difference of each of the obtained intensity values before and after the soiled textiles were washed. The greater the difference the more pronounced is the achieved lightening. [0000] Alginate + 0.15% Soil Reference Alginate CaCl 2 Engine oil 30.8 38.0 42.0 [0050] The results show that an increase in the fat dissolution power could already be achieved in regard to engine oil by adding the alginate to the washing agent composition; however a further significant increase in the fat dissolution power could be achieved by adding CaCl 2 . Example 2 Washing Tests with Pectin and Calcium Ions [0051] A washing agent composition comprising: [0000] Fatty alcohol polyethylene oxide 7.0% LAS 9.0% Coconut fatty acid 4.0% Boric acid 1.0% Citric acid 2.0% Propylene glycol 6.0% PTPMP 0.2% NaOH 3.1% Protease 0.8% Amylase 0.1% Water remainder was mixed on the one hand with 2 wt. % of pectin (PEKTIN AMID AF 025 from Herbstreith & Fox), on the other hand with 2 wt. % pectin as well as 0.15 wt. % of CaCl 2 . Textiles made of pure cotton were then washed with these washing agent compositions as well as with a washing agent composition as a comparison without added pectin and CaCl 2 . [0052] A washing machine Miele W 918 Novotronic was used for the washing tests. 3.5 kg of clean washing was washed with the standard program with a simple wash cycle at 40° C. using water with a German hardness of 16°. The liquid volume was 18 liters. In order to obtain a statistical mean, 5 parallel wash tests were each carried out. [0053] The clean textiles were each washed three times under the abovementioned conditions each with 100 g of the previously cited washing agent composition. After the third cycle the textiles were soiled with engine oil. The intensity of the soils was recorded with a Minolta camera CR 200 and then left at room temperature for 7 days. The aged soils were then washed again under the previously cited conditions, then allowed to dry and the intensity values of the soils were again determined with the Minolta camera CR 200. [0054] The differences in the intensity values are listed below and were obtained from the difference of each of the obtained intensity values before and after the soiled textiles were washed. The greater the difference the more pronounced is the achieved lightening. [0000] Alginate + 0.15% Soil Reference Alginate CaCl 2 Engine oil 30.8 40.7 45.7 [0055] The results show that an increase in the fat dissolution power could already be achieved in regard to engine oil by adding the alginate to the washing agent composition; however a further significant increase in the fat dissolution power could be achieved by adding CaCl 2 . Example 3 Formulations [0056] [0000] E1 E2 E3 C12-18 Fatty acid 7.5 6 3 C12-18 Fatty acid with 7 EO 12 12 10 Sodium lauryl ether sulfate with 2 EO 5 2 5 C12-C14-APG — — 2.5 Linear C10-13 alkylbenzene sulfonic acid 9.6 16 — Citric acid 3 3.5 1 Phosphonic acid 1 0.8 0.2 Boric acid 1 1 1 Polyacrylate thickener 0.35 0.75 0.1 NaOH (50% conc.) 4.70 5.4 1.48 Optical brightener 0.08 0.1 0.04 1,2-Propane diol 7 8.5 — Glycerin — — 4.5 Silicone defoamer 0.1 0.1 0.01 Enzymes (cellulase, protease & amylase) 1.4 1.4 0.6 Perfume 1.5 1.5 0.75 Alginate 2.5 — 1 Pectin — 3 2.5 CaCl 2 0.05 0.1 0.1 Colorant + + + Water ad 100 ad 100 ad 100 [0057] While at least one exemplary embodiment has been presented in the foregoing detailed description of the invention, it should be appreciated that a vast number of variations exist. It should also be appreciated that the exemplary embodiment or exemplary embodiments are only examples, and are not intended to limit the scope, applicability, or configuration of the invention in any way. Rather, the foregoing detailed description will provide those skilled in the art with a convenient road map for implementing an exemplary embodiment of the invention, it being understood that various changes may be made in the function and arrangement of elements described in an exemplary embodiment without departing from the scope of the invention as set forth in the appended claims and their legal equivalents.

The present invention relates to the use of polymers comprising carboxyl groups in combination with bivalent cations for producing a protective layer on a textile sheet material and to textile treatment agents, in particular washing and cleaning agents containing said polymers in a suitable form of administration, in order to enable the formation of a protective layer on textile sheet materials.

BACKGROUND OF THE INVENTION [0001] 1. Field of the Invention [0002] This invention relates to a method of and system for image processing for trimming, and more particularly, to a method of and system for image processing for trimming photographic images of objects comprising a plurality of parts. This invention further relates to a computer program for the image processing. [0003] 2. Description of the Related Art [0004] For example, application of a passport or a license or making own personal history often requires a photograph of his or her face output in a predetermined standard (will be referred to as “a certification photograph”, hereinbelow.) For this purpose, a studio for taking a photograph of the user has been provided and there has been used an automatic camera which automatically takes a photograph of the user seated on a chair in the studio and makes a certification photograph sheet on which a photograph of his or her face is recorded. Such an automatic photograph system is inconvenient in that the place of installment is limited since it is cumbersome, and the user has to find it and visit it in order to obtain the certification photograph. [0005] In order to overcome this problem, it has been proposed to obtain the position of the face from the photographic image of the face employed in making a certification photograph, set a trimming area on the basis of the standard of the certification photograph so that the photographic image of the face is positioned in a predetermined position in the certification photograph, and cut out the image in the trimming area, thereby forming the certification photograph. With this method, the user can request a certification photograph of a DPE shop or the like which exists more than the automatic photograph systems and at the same time, the user can request a DPE shop or the like to make a certification photograph from a photograph which he or she favors. [0006] From the characteristics of the certification photograph, it is necessary that the image of the whole face is in the trimming area and the trimming area is laterally symmetrical about the center of the image of the face. Accordingly, when setting the trimming area, generally, the centerline of the face is set to be the centerline of the trimming (will be referred to as “the trimming centerline”, hereinbelow) and the area which is laterally symmetrical about the trimming centerline is set to be the trimming area. The centerline of the face may be a straight line joining the middle point between eyes, the center point of the nose and the center point of the mouth as disclosed in Japanese Unexamined Patent Publication No. 2003-092726 and the frame of the trimming area may be set so that the centerline of the face is taken as the trimming centerline and the vertical lines are parallel to the trimming centerline. With this method, even if the image of the face in the input photographic image is inclined ( FIG. 21A ), it is possible to set the image of the face not to be inclined ( FIG. 21C ). [0007] However, the method disclosed in Japanese Unexamined Patent Publication No. 2003-092726 is disadvantageous in that, though it is possible to carry out trimming so that neither the image of the face nor the image of the trunk is inclined if the image of the face and the image of the trunk are inclined in substantially the same degree in substantially the same direction when taking the photograph, the trimmed image is bad in its balance as a whole e.g., the inclination of the image of the trunk can be very hard as shown in FIG. 21C or the image of the trunk can be abnormally small, when the photograph is trimmed with the centerline of the face taken as the trimming centerline if the images of the face and the trunk which originally should have the same centerline have different centerlines, e.g., only the image of the face is inclined. SUMMARY OF THE INVENTION [0008] In view of the foregoing observations and description, the primary object of the present invention is to provide an image processing method, an image processing system and a computer program for the purpose which can perform the trimming in a good balance. [0009] In accordance with the present invention, there is provided an image processing method in which a trimmed image is obtained by carrying out trimming for cutting out from a photographic image obtained by taking a photograph of an object comprising a reference part, and one or more other part which, in a state where the object is not inclined, has a common centerline with the reference part and is arranged in a direction in which the centerline of the reference part extends, an image of an area including a part or the whole of the reference part and said other part along a trimming centerline at a predetermined angle to the centerline of the reference part, wherein the improvement comprises the steps of [0010] obtaining the centerline of the reference part and at the same time, detecting the degree of inclination of said other part and the direction thereof upon taking the photograph from the photographic image, [0011] determining said predetermined angle so that the trimming centerline is inclined by a larger angle away from the centerline of the reference part toward the direction of the inclination of said other part as the degree of inclination of said other part increases on the basis of the detected degree of inclination of said other part, and [0012] carrying out the trimming along a trimming centerline at the determined angle. [0013] The “trimming centerline” as used here means the centerline of the area to be cut out upon trimming, and the trimmed image is an image laterally symmetrical about the trimming centerline. [0014] The “inclination of said other part” means inclination of said other part relative to the reference part and the inclination of said other part includes not only those due to inclination of said other part upon taking the photograph but also those due to inclination of the reference part or both the reference part and said other part upon taking the photograph. Since the image processed by the method of the present invention is a photographic image of an object comprising a reference part, and one or more other part which has a common centerline with the reference part in a state where no part is inclined as an image of upper part of a person comprising a face and a trunk, the inclination of said other part relative to the reference part is equal to the inclination of the centerline of said other part to the centerline of the reference part. [0015] It is preferred in the image processing method that the degree of importance of said other part be obtained and said predetermined angle be larger as the degree of importance of said other part increases. [0016] The “degree of importance” means a degree to which much importance be attached to the direction of said other part relative to the reference part in the trimmed image. [0017] The image processing method of the present invention can be applied to trimming of a photographic image of a face of a person. In this case, said object is formed by the upper half of the person, the reference part is formed by the face of the person, and said other part is formed by the trunk of the person. [0018] In accordance with the present invention, there is provided an image processing system in which a trimmed image is obtained by carrying out trimming for cutting out from a photographic image obtained by taking a photograph of an object comprising a reference part, and one or more other part which, in a state where the object is not inclined, has a common centerline with the reference part and is arranged in a direction in which the centerline of the reference part extends, an image of an area including a part or the whole of the reference part and said other part along a trimming centerline at a predetermined angle to the centerline of the reference part, wherein the improvement comprises [0019] a reference part centerline obtaining means which obtains the centerline of the reference part from the photographic image, [0020] an inclination detecting means which detects the degree of inclination of said other part and the direction thereof upon taking the photograph from the photographic image, [0021] a trimming angle determining means which determines said predetermined angle so that the trimming centerline is inclined by a larger angle away from the centerline of the reference part toward the direction of the inclination of said other part as the degree of inclination of said other part increases on the basis of the detected degree of inclination of said other part, and [0022] a trimming means which carries out the trimming along a trimming centerline at the determined angle. [0023] It is preferred that the image processing system of the present invention further comprises an importance degree obtaining means which obtains the degree of importance of said other part and said predetermined angle be larger as the degree of importance of said other part increases. [0024] The image processing system of the present invention can be applied to trimming of a photographic image of a face of a person. In this case, said object is formed by the upper half of the person, the reference part is formed by the face of the person, and said other part is formed by the trunk of the person. [0025] Further, it is preferred that the reference part centerline obtaining means obtains the positions of the eyes and obtains as the centerline of the reference part a straight line which passes the middle point between the eyes and is perpendicular to the straight line joining the eyes. [0026] The inclination detecting means may detect the degree of inclination of the shoulders which are included in said trunk and may detect the degree of inclination of the trunk and the direction thereof on the basis of the difference between the degrees of inclination of the shoulders. [0027] The image processing method of the present invention may be recorded in a computer-readable medium as a computer program for causing a computer to execute an image processing method of the present invention, and the computer-readable medium may be provided together with the computer program. A skilled artisan would know that the computer-readable medium is not limited to any specific type of storage devices and includes any kind of device, including but not limited to CDs, floppy disks, RAMs, ROMs, hard disks, magnetic tapes and internet downloads, in which computer instructions can be stored and/or transmitted. Transmission of the computer code through a network or through wireless transmission means is also within the scope of this invention. Additionally, computer code/instructions include, but are not limited to, source, object and executable code and can be in any language including higher level languages, assembly language and machine language. [0028] In accordance with the image processing method and system of the present invention, when trimming a photographic image of an object comprising a reference part, and one or more other part which has a common centerline with the reference part in a state where no part is inclined as an image of upper part of a person comprising a face and a trunk, the inclination of said other part relative to the reference part is detected and the trimming centerline is obtained by inclining the centerline of the reference part according to the inclination of said other part instead of employing the centerline of the reference part as the trimming centerline as it is. Accordingly, when said other part is not inclined relatively to the reference part, both the reference part and said other part can be cut out not inclined and at the same time, when said other part is inclined relatively to the reference part, though an image of the reference part is somewhat inclined in the trimmed image, an image of said other part is not extremely inclined in the trimmed image, which permits the trimming to be performed in a good balance. [0029] Further, since the centerline of the reference part can be inclined at an angle according to the degree of importance of the part, a trimmed image reflecting the kind of the image, the application of the trimmed image or the user's taste can be obtained. BRIEF DESCRIPTION OF THE DRAWINGS [0030] FIG. 1 is a block diagram showing an ID card issue system in accordance with an embodiment of the present invention, [0031] FIG. 2 is a block diagram showing the ID card making center in the embodiment shown in FIG. 1 , [0032] FIG. 3 is a block diagram showing the face detecting portion of the ID card making center shown in FIG. 2 , [0033] FIG. 4 is a block diagram showing the eye detecting portion of the ID card making center shown in FIG. 2 , [0034] FIGS. 5A and 5B are views for illustrating the positions of the eyes, [0035] FIG. 6A is a view showing the horizontal edge detecting filter, [0036] FIG. 6B is a view showing the vertical edge detecting filter, [0037] FIG. 7 is a view for illustrating calculation of a gradient vector, [0038] FIG. 8A is a view showing the face of a person, [0039] FIG. 8B is a view showing gradient vectors near the eyes and the mouth of the face of a person shown in FIG. 8A , [0040] FIG. 9A is a view showing the histogram of the size of the gradient vector before normalization, [0041] FIG. 9B is a view showing the histogram of the size of the gradient vector after normalization, [0042] FIG. 9C is a view showing the histogram of the size of the five-valued gradient vector, [0043] FIG. 9D is a view showing the histogram of the size of the five-valued gradient vector after normalization, [0044] FIG. 10 are views showing the sample images which have been known that they are the images of face and are used in learning the reference data E 1 , [0045] FIG. 11 are views showing the sample images which have been known that they are the images of face and are used in learning the reference data E 2 , [0046] FIGS. 12A to 12 C are views for illustrating rotation of faces, [0047] FIG. 13 is a flowchart showing learning of the reference data, [0048] FIG. 14 is a view showing derivation of the distinguishers, [0049] FIG. 15 is a view showing the stepwise deformation of the images to be distinguished, [0050] FIG. 16 is a block diagram showing the structure of the trunk inclination detecting portion in the ID card making center shown in FIG. 2 , [0051] FIG. 17 is a block diagram showing the structure of the shoulder detection range setting portion of the trunk inclination detecting portion shown in FIG. 16 , [0052] FIG. 18 is a view for illustrating the action of the shoulder detection range setting portion shown in FIG. 17 , [0053] FIG. 19 is a view for illustrating the action of the inclination detecting portion shown in FIG. 16 , [0054] FIG. 20 is a block diagram showing the structure of the trimming centerline setting portion in the ID card making center shown in FIG. 2 , [0055] FIGS. 21A to 21 C are views showing examples of the photographic images and the trimmed images, and [0056] FIG. 22 is a flowchart showing the processing in the ID card making center shown in FIG. 2 . DESCRIPTION OF THE PREFERRED EMBODIMENT [0057] FIG. 1 is a block diagram showing an ID card issue system in accordance with an embodiment of the present invention. In the ID card issue system of this embodiment, photographic images of the face obtained by photographing persons at various photographing points are sent to an ID card making center (will be described in detail later), in which trimming is carried out on the photographic images sent from the photographing points to obtain trimmed images, and ID cards with a photograph are made by the use of the trimmed images, and the trimming is executed by causing a computer (e.g., a personal computer) to perform the processing program read in an auxiliary storage means. The processing program is stored in a recording medium such as a CD-ROM or distributed by way of a network such as the Internet, and installed in the computer. [0058] As shown in FIG. 1 , the ID card issue system of this embodiment comprises a plurality of photographing points 1 at which persons are photographed and photographic images are obtained and an ID card making center 100 which makes ID cards with a photograph by the use of the face images obtained at the photographing points 1 . The photographing points 1 and the ID card making center 100 are connected by way of a network 5 , and the images are sent from the photographing points 1 to the ID card making center 100 are connected by way of the network 5 . [0059] FIG. 2 is a block diagram showing the ID card making center 100 . [0060] As shown in FIG. 2 , the ID card making center 100 comprises an image input portion 10 through which photographic images S 0 are input, a face detecting portion 20 which detects the approximate position and size of the face in each of the images S 0 from the image input portion 10 and obtains the image of the face S 1 (will be referred to as “the face image S 1 ”, hereinbelow), an eye detecting portion 30 which detects the positions of the eyes in the face image S 1 , a database 40 which stores reference data E 1 and reference data E 2 which are used in the face detecting portion 20 and the eye detecting portion 30 as will be described later, a trunk inclination detecting portion 50 which detects the inclination of the trunk of the person photographed in the image S 0 , a trimming centerline setting portion 60 which sets a trimming centerline, on the basis of which the image S 0 is trimmed, on the basis of the positions of the eyes detected by the eye detecting portion 30 , the inclination of the trunk detected by the trunk inclination detecting portion 50 and a degree of importance a of the trunk set by an importance degree setting portion 80 to be described later, the importance degree setting portion 80 , a trimming performing portion 85 which obtains a trimming area on the basis of the positions of the eyes detected by the eye detecting portion 30 and the trimming centerline set by the trimming centerline setting portion 60 and at the same time, cuts out the image of the obtained trimming area to obtain a trimmed image S 2 , and a card making portion 90 which makes an ID card with a photograph P by carrying out necessary enlargement/contraction, printing or the like on the trimmed image S 2 . [0061] The image input portion 10 is for inputting the photographic images S 0 to be processed by the ID card issue system of this embodiment and forms a receiving portion which receives the photographic images S 0 sent by way of the network 5 . The photographic images S 0 to be processed by the image processing method and system of the present invention include not only the photographic images taken by a digital camera but also those printed on a printing medium such as a paper and a printing paper and those photoelectrically read images on photographic film by, for instance, a scanner. [0062] FIG. 3 is a block diagram showing the face detecting portion 20 of the ID card making center 100 shown in FIG. 2 . As shown in FIG. 3 , the face detecting portion 20 comprises a first characteristic value calculating portion 22 which calculates a characteristic value C 0 from the photographic images S 0 and a face detection performing portion 24 which performs face detection by the use of the characteristic value C 0 and the reference data E 1 stored in the database 40 . The reference data E 1 stored in the database 40 and the face detecting portion 20 will be described in detail, hereinbelow. [0063] The first characteristic value calculating portion 22 of the face detecting portion 20 calculates the characteristic value C 0 from the photographic images S 0 . For example, the first characteristic value calculating portion 22 calculates gradient vectors as the characteristic value C 0 . Calculation of the gradient vectors will be described, hereinbelow. The first characteristic value calculating portion 22 first detects horizontal edges by carrying out on the images S 0 filtering by the use of a horizontal edge detecting filter shown in FIG. 6A . Then the first characteristic value calculating portion 22 detects vertical edges by carrying out on the images S 0 filtering by the use of a vertical edge detecting filter shown in FIG. 6B . The first characteristic value calculating portion 22 further calculates a gradient vector K for each pixel as shown in FIG. 7 on the basis of the size H of the horizontal edge and the size V of the vertical edge of each pixel on the images S 0 . [0064] The gradient vectors K thus calculated, in the case of a face of a person as shown in FIG. 8A , are directed toward the center of an eye or a mouth in a dark part such as eyes or a mouth and are directed outward from the position of a nose in a light part such as a nose. Since the eye is larger than the mouth in change of density, the gradient vectors K are larger in the eye than in the mouth. [0065] The direction and the size of the gradient vector are taken as the characteristic value C 0 , The direction of the gradient vector K is of a value of 0 to 359° with a predetermined direction (e.g., x direction in FIG. 7 ) taken as a reference. [0066] Then the size of the gradient vector K is normalized. The normalization is effected by obtaining a histogram of the sizes of the gradient vectors K of all the pixels in the images S 0 , smoothening the histogram so that the distribution of the sizes of the gradient vectors K are uniformed over the range of values which the pixels in the images S 0 can take (0 to 255 in the case of 8 bit signals), and correcting the sizes of the gradient vectors K on the basis of the smoothening. For example, when the sizes of the gradient vectors K is small and the histogram thereof leans toward the smaller side as shown in FIG. 9A , the sizes of the gradient vectors K are normalized so that the sizes of the gradient vectors K are distributed over the entire range of 0 to 255 and the histogram is as shown in FIG. 9B . In order to reduce the amount of calculation, it is preferred that the distribution range of the gradient vectors in the histogram be divided into, for instance, five, and the gradient vectors be normalized so that the sizes of the gradient vectors K are distributed over the entire range of 0 to 255 in all the frequency distributions divided into five as shown in FIG. 9D . [0067] The reference data E 1 stored in the database 40 is obtained by defining the distinguishing conditions to a combination of the characteristic values C 0 in each of the pixels forming each pixel group for each of a plurality of pixel groups comprising a combination of a plurality of pixels selected from sample images to be described later. [0068] The distinguishing conditions to a combination of the characteristic values C 0 in each of the pixels forming each pixel group in the reference data E 1 have been determined in advance by learning a plurality of sample images which have been known that they are the images of face and a plurality of sample images which have been known that they are not the images of face. [0069] When the reference data E 1 is generated in this embodiment, as the sample images which have been known that they are the images of face, sample images each of which has a size of 30×30 pixels, in which the center-to-center distances between the eyes are 10 pixels, 9 pixels, and 11 pixels and which are obtained by rotating the image of the face perpendicular to the straight line joining the centers of the eyes stepwise by 3° within ±15° in the plane (i.e., −15°, −12°, −9°, −6°, −3°, −0°, 3°, 6°, 9°, 12°, 15°) as shown in FIG. 10 are employed for each face. That is, 33 (3×11) sample images are prepared for each face. In FIG. 10 , only the sample images obtained by rotating the image of the face perpendicular to the straight line joining the centers of the eyes by −15°, 0° and +15° in the plane are shown. The center of rotation is the intersection of the diagonal lines of the sample image. The centers of the eyes are the same in the case of the sample images in which the center-to-center distances between the eyes are 10 pixels. Coordinates of the centers of the eyes are taken as (x 1 , y 1 ) and (x 2 , Y 2 ) in the coordinate system having an origin on the upper left corner of the sample image. The positions of the eyes in the vertical direction (i.e., y 1 and y 2 ) are the same in all the sample images. [0070] As the sample images which have been known that they are not the images of face, arbitrary sample images each of which has a size of 30×30 pixels are employed. [0071] In the case where the sample images which have been known that they are the images of face, are 10 pixels in the center-to-center distances between the eyes and 0° in the rotational angle (that is, the images where the face is vertical) are learned, only the images of faces which are 10 pixels in the center-to-center distances between the eyes and are not rotated by any angle will be distinguished as a face image when the reference data E 1 is referred to. The sizes of the face images which can be included in the photographic images S 0 are not constant. Accordingly, the photographic images S 0 are enlarged or contracted to distinguish a position of face which conforms in size to the sample images when determining whether a face image is included in the photographic images S 0 as will be described later. However, in order to enlarge or contract an image so that the center-to-center distances between the eyes thereof is accurately 10 pixels, it is necessary to effect the distinguishment while the photographic images S 0 is enlarged or contracted stepwise, for instance, by 1.1, which results in a vast amount of calculation. [0072] The face images which can be included in the photographic images S 0 can include not only the images where the face rotational angle is 0° as shown in FIG. 12A but also the images where the face is rotated as shown in FIGS. 12B and 12C . However, when the sample images which are 10 pixels in the center-to-center distances between the eyes and 0° in the rotational angle are only learned, the faces rotated as shown in FIG. 12B or 12 C cannot be distinguished as a face. [0073] Accordingly, in this embodiment, the sample images in which the center-to-center distances between the eyes are 9 pixels, 10 pixels, and 11 pixels and which are obtained by rotating the image of the face perpendicular to the straight line joining the centers of the eyes stepwise by 3° within ±15° in the plane as shown in FIG. 10 are employed as the sample images which have been known that they are the images of face so that the learning of reference data E 1 has a tolerance. By this, when the face detection performing portion 24 to be described later effects the distinguishment, the photographic images S 0 have only to be enlarged or contracted stepwise by 11/9 and accordingly the calculating time can be shortened as compared with when the photographic images S 0 have to be enlarged or contracted stepwise by 1.1. Further, the faces which have been rotated as shown in FIG. 12B or 12 C can be distinguished. [0074] An example of learning the sample image group will be described with reference to the flow chart shown in FIG. 13 , hereinbelow. [0075] In FIG. 14 , each of the pixels forming the distinguisher are a pixel P 1 on the center of the right eye, a pixel P 2 on the right cheek, a pixel P 3 on the forehead and a pixel P 4 on the left cheek of the sample images which have been known that they are the images of face as shown on the left side of FIG. 14 . Then the combination of the characteristic values C 0 on all the pixels P 1 to P 4 for all the sample images which have been known that they are the images of face, and the histogram thereof is made. Though the characteristic value represents the direction and size of the gradient vector K, since the direction of the gradient vector K is written in 360 (0 to 359) ways and the size of the gradient vector K is written in 256 (0 to 255) ways, the combination can be written in (360×256) ways per one pixel when they are used as they are. That is, the combination for 4 pixels can be written in (360×256) 4 ways when they are used as they are and a vast number of samples, a long time and a vast number of memories are required. Accordingly, in this embodiment, the direction 0 to 359 of the gradient vector K is four-valued into a rightward direction (0 to 44 and 315 to 359, value 0), an upward direction (45 to 134, value 1), a leftward direction (135 to 224, value 2) and a downward direction (225 to 314, value 3) and the size of the gradient vector K is three-valued (values 0 to 2). Then the value of the combination is calculated according to the following formulae. the value of the combination=0 (in the case where the size of the gradient vector=0) the value of the combination=((the direction of the gradient vector+1)×the size of the gradient vector (in the case where the size of the gradient vector>0)) [0076] Since the number of combinations becomes 9 4 with this arrangement, the number of pieces of data on the characteristic value can be reduced. [0077] Similarly, a histogram is made for the sample images which have been known that they are not the images of face. In the case of the sample images which have been known that they are not the images of face, pixels corresponding to the positions of the pixels P 1 to P 4 on the sample images which have been known that they are the images of face are used. The histogram representing the logarithmic values of the ratio of the frequencies shown by the two histograms is the histogram which is shown on the rightmost side of FIG. 14 and used as the distinguisher. The value of the ordinate shown by each of the histograms of the distinguisher will be referred to as “the distinguishing point”, hereinbelow. In accordance with the distinguisher, there is a strong probability that the images exhibiting a distribution of the characteristic values corresponding to a positive distinguishing point are images of face, and as the absolute values of the distinguishing point increases, the probability becomes stronger. Conversely, there is a strong probability that the images exhibiting a distribution of the characteristic values corresponding to a negative distinguishing point are not images of face, and as the absolute values of the distinguishing point increases, the probability becomes stronger. In step S 2 , on the basis of the combination of the characteristic values C 0 on all the pixels forming a plurality of pixel groups which may be employed in the distinguishment, a plurality of the distinguishers in the form of a histogram are made. [0078] Then, out of the distinguishers made in step S 2 , a distinguisher which is the most effective to distinguish whether the image is of a face is selected. This selection is effected taking into account the weights of the sample images. In this example, the ratio of the weighted correct answers of the distinguishers, and the distinguisher exhibiting the highest weighted correct answer is selected. (step S 3 ) That is, since initially the sample images are equally weighted by 1, the distinguisher having the most sample images which are correctly distinguished as the image of face by the distinguisher is selected as the most effective distinguisher in the initial step S 3 . Whereas, in second step S 3 after the weight of each sample image is updated in step S 5 as will be described later, sample images whose weight is 1, sample images whose weight is larger than 1 and sample images whose weight is smaller than 1 mingle with each other and the sample image whose weight is larger than 1 is more counted than the sample whose weight is 1 in the evaluation of the ratio of the correct answers. By this, in steps S 3 after the second step S 3 , a more importance is put on the sample images weighted more than the sample images weighted less. [0079] Then whether the ratio of the correct answers of the combination of the distinguishers up to that time, that is, the ratio at which the result of distinguishment whether the sample images are images of face by the use of the distinguishers combined up to that time conforms to the answer whether the sample images are actually images of face, exceeds a predetermined threshold value is checked. (step S 4 ) The sample images used here in the evaluation of the ratio of the correct answers may be the sample images with a current weight or the equally-weighted sample images. When the ratio exceeds the predetermined threshold value, the learning is ended since whether the images are of a face can be distinguished at a sufficiently high probability by the use of the distinguishers selected up to that time. When the ratio does not exceed the predetermined threshold value, the processing proceeds to step S 6 in order to select one or more additional distinguisher to be combined with the distinguishers selected up to that time. [0080] In step S 6 , in order for the distinguisher(s) selected in recent step S 3 not to be selected again, the once-selected distinguisher(s) is omitted. [0081] Then, the weight on the sample image which was not correctly distinguished whether it is an image of face in the preceding step S 3 is increased and the weight on the sample image which was correctly distinguished whether it is an image of face in the preceding step S 3 is reduced. (step S 5 ) The reason why the weights are increased or reduced is that an importance is put on an image which was not correctly distinguished by the distinguishers which have been already selected so that a distinguisher which can correctly distinguish the image whether it is of a face, thereby enhancing the effect of the combination of the distinguishers. Thereafter, the processing returns to step S 3 where the next most effective distinguishers are selected. [0082] After distinguishers corresponding to the combination of characteristic values Co in each of the pixels forming a particular pixel group is selected as distinguishers which are suitable for distinguishing whether the image includes a face by repeating steps S 3 to S 6 , the kind of the distinguishers and the distinguishing conditions used in distinguishment of whether the image includes a face are decided. (step S 7 ) Then the leaning of the reference data E 1 is ended. [0083] When the learning procedure described above is employed, the distinguisher need not be limited to those in the form of a histogram but may be any so long as it provides data on the basis of which whether the image is of a face can be distinguished by the use of the combination of characteristic values Co in each of the pixels forming a particular pixel group, e.g., the distinguisher may be two-valued data, a threshold value or a function. Further, just the same, in the form of a histogram, a histogram representing the distribution of the difference between the two histograms shown at the middle of FIG. 14 may be employed. [0084] Further, the learning procedure need not be limited to that described above but other machine learning procedures such as neural network may be employed. [0085] The face detection performing portion 24 refers to the distinguishing conditions which the reference data E 1 has learned for all the combinations of characteristic values Co in each of the pixels forming a plurality of pixel groups to obtain the distinguishing point of the combination of characteristic values Co in each of the pixels forming pixel groups, and detects a face on the basis of all the distinguishing points. At this time, the direction and the size of the gradient vector which are the characteristic value Co are four-valued and three-valued, respectively. In this embodiment, all the distinguishment points are summed and a face is detected on the basis of whether the sum is positive or negative, and of the magnitude of the sum. For example, when the sum of the distinguishment points is positive, it is determined that the image is of a face, whereas when the sum of the distinguishment points is negative, it is determined that the image is not of a face. [0086] The photographic images S 0 can differ from the sample images of 30 pixels×30 pixels and can be of various sizes. Further, when the image includes a face, the face sometimes rotated by an angle other than 0°. Accordingly, the face detection performing portion 24 , while enlarging or contracting the photographic image S 0 until the vertical side or the horizontal side thereof becomes 30 pixels and stepwise rotating it through 360° in the plane ( FIG. 15 shows a state where the image is contracted), sets a mask M of 30×30 pixels on the photographic image enlarged or contracted in each step, and distinguishes whether the image in the mask M is of a face (that is, whether the sum of the distinguishing points is positive or negative) while moving the mask M one pixel by one pixel on the enlarged or contracted photographic image S 0 as shown in FIG. 15 . This distinguishment is carried out on the photographic image C 0 in all the steps of enlargement/contraction and rotation, and the area of 30×30 pixels corresponding to the position of the mask M at the detection is detected as a face area from the photographic image S 0 of the size and the rotational angle in the step in which the sum of the distinguishing points is positive and the largest, and at the same time, the image in this area is extracted as a face image S 1 from the photographic image S 0 . [0087] Further, since the center-to-center distances between the eyes are 9, 10, or 11 pixels in the sample images employed when the sample images are learned to generate the reference data E 1 , the ratio of enlargement to enlarge or contract the photographic image S 0 may be 11/9. Since in the sample images used in learning upon generation of the reference data E 1 , faces are rotated within ±15° in the plane, the photographic images SO have only to be rotated through 360° 30° by 30°. [0088] The first characteristic value calculating portion 22 calculates the characteristic value on each stage of deformation of the photographic images S 0 , e.g., enlargement/contraction or the rotation of the photographic images S 0 . [0089] The face detecting portion 20 thus detects approximate positions and the sizes of the faces from the photographic images S 0 , and obtains the face images S 1 . [0090] The eye detecting portion 30 detects the positions of the eyes from the face images S 1 obtained by the face detecting portion 20 and FIG. 4 is block diagram showing the arrangement of the eye detecting portion 30 . As shown in FIG. 4 , the eye detecting portion 30 comprises a second characteristic value calculating portion 32 which calculates a characteristic value C 0 from the face images S 1 and an eye detection performing portion 34 which performs the eye detection on the basis of the characteristic value C 0 and the reference data E 2 stored in the database 40 . The position of the eye to be distinguished by the eye detection performing portion 34 is the center between the outside corner of the eye and the inner side of the eye indicated at x in FIG. 5A or 5 B. In the case of an eye looking right ahead, it is the same as the center of the pupil as shown in FIG. 5A whereas in the case of an eye looking rightward, it is in a position deviated from the center of the pupil or on the white of the eye. [0091] Since being the same as the first characteristic value calculating portion 22 in the face detecting portion 20 shown in FIG. 3 except that it calculates the characteristic value C 0 from the face images S 1 instead of the photographic image S 0 , the second characteristic value calculating portion 32 will not be described in detail. [0092] The second reference data E 2 stored in the database 40 defines the distinguishing conditions, for each of a plurality of pixel groups comprising a combination of a plurality of pixels selected from the sample images to be described later, for distinguishing the combination of the characteristic value C 0 of each of the pixels forming each of the pixel groups as the first reference data E 1 . [0093] For learning of the second reference data E 2 , there are used sample images which are 9.7 pixels, 10 pixels and 10.3 pixels in the center-to-center distances between the eyes and are obtained by rotating the image of the face stepwise by 1° within ±3° in the plane. Accordingly, the second reference data E 2 is narrow in the tolerance of learning as compared with the first reference data E 1 , and in accordance with the second reference data E 2 , the positions of the eyes can be detected more accurately. Further, since being equal to learning of the first reference data E 1 except the sample pixel groups employed, the second reference data E 2 will not be described here. [0094] The eye detection performing portion 34 obtains, referring to the distinguishing conditions which the second reference data E 2 has learned on all the combinations of the characteristic values C 0 in the, the distinguishing point on the combination of each of the pixels forming each of the pixel groups and distinguishes the position of the eyes included in the face on the basis of all the distinguishing points. At this time, the direction and the size of the gradient vector K which are the characteristic values C 0 are respectively four-valued and three-valued. [0095] The eye detection performing portion 34 , while stepwise enlarging or contracting the face image S 1 obtained by the face detecting portion 20 and stepwise rotating it through 360° in the plane, sets a mask M of 30×30 pixels on the face image enlarged or contracted in each step, and detects the position of the eyes while moving the mask M one pixel by one pixel on the enlarged or contracted face image. [0096] Further, since the center-to-center distances between the eyes are 9.07, 10, or 10.3 pixels in the sample images employed when the sample images are learned to generate the second reference data E 2 , the ratio of enlargement to enlarge or contract the photographic image S 0 may be 10.3/9.7. Since in the sample images used in learning upon generation of the reference data E 1 , faces are rotated within ±3° in the plane, the face images S 1 have only to be rotated through 360° 6° by 6°. [0097] The second characteristic value calculating portion 32 calculates the characteristic value C 0 on each stage of deformation, e.g., enlargement/contraction or the rotation of the face images S 1 . [0098] Then, in this embodiment, all the distinguishing points are summed on all the stages of deformation of the face images S 1 , and in the image in the 30×30 pixel mask M on the stage of deformation where the sum is the largest, a coordinate system having its origin on the upper left corner is set. Then positions corresponding to coordinates (x 1 , y 1 ) and (x 2 , y 2 ) of the positions of eyes of the sample image are obtained and positions corresponding to the positions in the face image S 1 before deformation are detected as the positions of the eyes. [0099] The eye detecting portion 30 thus detects positions of the eyes from the face image S 1 obtained by the face detecting portion 20 . [0100] The trunk inclination detecting portion 50 of the ID card making center 100 detects the inclination of the trunk of the person photographed in the image S 0 relative to the image of the face on the basis of the positions of the right and left eyes detected by the eye detecting portion 30 and FIG. 16 is a block diagram showing the structure thereof. As shown in FIG. 16 , the trunk inclination detecting portion 50 comprises a shoulder detection range setting portion 52 , an edge detecting portion 54 , a shoulder line obtaining portion 56 and an inclination calculating portion 58 . The trunk inclination detecting portion 50 will be described in detail hereinbelow. [0101] As shown in FIG. 17 , the shoulder detection range setting portion 52 comprises a face frame estimating portion 52 a and a shoulder range estimating portion 52 b. The face frame estimating portion 52 a calculates a distance D between the right and left eyes on the basis of the positions of the eyes (A 1 and A 2 ) detected by the eye detecting portion 30 and estimates the frame (the frame shown by the dotted line in the example shown in FIG. 18 ) of the face circumscribing the face according to the following formulae (1). La=D×Ua Lb=D×Ub Lc=D×Uc Ua=3.250 Ub=1.905 Uc=2.170 [0102] wherein La, Lb and Lc respectively represent the width of the frame of the face having its center on the middle point between the eyes in each of the photographic images S 0 as shown in FIG. 18 . The coefficients Ua, Ub and Uc are of values empirically obtained from a number of sample images and are stored in a storage portion (not shown). . . . (1) [0103] The shoulder range estimating portion 52 b estimates a range over which an image of a shoulder is to be detected, that is, a range in which an image of a shoulder can exist (abbreviated to a shoulder range, hereinbelow.) on the basis of the frame of the face estimated by the face frame estimating portion 52 a in the following manner in this example. The shoulder range estimating portion 52 b first obtains a straight line (will be referred to as “the face centerline”, hereinbelow) M which passes through the middle point between the eyes in perpendicular to a straight line joining the eyes. Then the shoulder range estimating portion 52 b estimates as the range of the left shoulder an area WL which is adjacent to the frame of the face, has the face centerline M as a part of the right side and is 1.5×La in width and La+Lb in height and estimates as the range of the right shoulder an area WR which is adjacent to the frame of the face, has the right side of the area WL as the left side thereof, and is the same as the area WL in size. The “right” or “left” as used here are as seen from the side of viewer of the photographic images S 0 . [0104] Then the shoulder detection range setting portion 52 outputs information representing the positions and the sizes of the ranges of the left and right shoulders WL and WR to the edge detecting portion 54 . [0105] The edge detecting portion 54 carries out edge detection processing in the vertical direction (the direction in which the face centerline M shown in Figure extends) on the ranges of the shoulders WL and WR and removes the edges which are of the strength not larger than a predetermined threshold value, thereby detecting contour lines shown by the thick line in FIG. 19 , that is, contour lines of the shoulders. The edge detecting portion 54 outputs information representing positions of pixels showing the contour lines to the shoulder line obtaining portion 56 . [0106] The shoulder line obtaining portion 56 carries out approximation by least square method on the two contour lines and obtains two straight lines N 1 and N 2 respectively as a left shoulder line and a right shoulder line. [0107] The inclination calculating portion 58 calculates the inclination of the image of the trunk relative to the image of the face on the basis of the straight line obtained by the shoulder line obtaining portion 56 . Specifically, the inclination calculating portion 58 first obtains the intersection B of the shoulder lines N 1 and N 2 and then obtains angles K 1 and K 2 which the shoulder lines N 1 and N 2 make with a line parallel to the face centerline M at the intersection B. In the photographic image S 0 , the angles K 1 and K 2 should be equal to each other when the image of the trunk is not inclined, and accordingly, the inclination calculating portion 58 calculates the inclination of the image of the trunk on the basis of the difference between the angles K 1 and K 2 . The “inclination of the image of the trunk” means inclination of the image of the trunk relative to the face and the inclination of the image of the trunk includes not only those due to inclination of the image of the trunk upon taking the photograph but also those due to inclination of the face upon taking the photograph. [0108] The inclination calculating portion 58 obtains the difference (K 1 −K 2 ) between the angles K 1 and K 2 , and calculates ½ of the absolute value of the difference as the degree of inclination of the trunk and obtains the direction of inclination on the basis of whether the difference (K 1 −K 2 ) is positive or negative. For example, when the difference (K 1 −K 2 ) is positive, that is K 1 >K 2 , the inclination calculating portion 58 determines that the inclination is in the clockwise direction and when the difference (K 1 −K 2 ) is negative, that is K 1 <K 2 , the inclination calculating portion 58 determines that the inclination is in the counterclockwise direction. In the example shown in FIG. 19 , the inclination is in the clockwise direction. [0109] The inclination calculating portion 58 outputs the degree of inclination of the trunk and the direction of inclination thus obtained to the trimming centerline setting portion 60 . [0110] FIG. 20 is a block diagram showing the structure of the trimming centerline setting portion 60 . As shown in FIG. 20 , the trimming centerline setting portion 60 comprises a reference centerline calculating portion 62 which calculates a reference centerline and a centerline correcting portion 64 which obtains a trimming centerline by correcting the reference centerline. [0111] Since the ID card issue system of this embodiment issues an ID card with a photograph, the reference centerline calculating portion 62 calculates a face centerline M such as shown in FIG. 21A as the reference centerline. The face centerline M is a straight line passing through the middle point Pm between the right and left eyes in perpendicular to a straight line joining the positions of the eyes, and may be newly obtained on the basis of the positions of the eyes detected by the eye detecting portion 30 or may be the face centerline M calculated when the shoulder range estimating portion 52 b estimates the range of an image of a shoulder. [0112] In the conventional trimming, since the trimmed image is obtained by taking the face centerline as the trimming centerline and cutting out the areas laterally symmetrical to the trimming centerline, in the case of a photographic image where the image of the trunk is inclined relative to the image of the face as shown in FIG. 21A , the inclination of the image of the trunk is prominent in the trimmed image (the part of the image in the dotted frame in FIG. 21C ), and the trimmed image is not good in balance. [0113] Accordingly, the trimming centerline setting portion 60 in the ID card making center 100 of the ID card issue system of this embodiment obtains a trimming centerline M′ shown in FIG. 21B by correcting the face centerline M by the centerline correcting portion 64 according to the inclination of the image of the trunk detected by the trunk inclination detecting portion 50 and the degree of importance a of the trunk set by the importance degree setting portion 80 . For example, a line obtained by rotating the face centerline M about the middle point Pm between the right and left eyes in the direction of the inclination is employed as the trimming centerline M′. The angle K by which the face centerline M is rotated is calculated according to the following formula (2). K=α×|K 1− K 2|/2, (0≦α≦1)   (2) [0000] wherein K represents the angle by which the face centerline M is rotated, K 1 and K 2 represent the angles which the shoulder lines make with the face centerline M, and a represents the degree of importance. [0114] Further, in this embodiment, the importance degree setting portion 80 comprises an input means (not shown) through which the user inputs the importance degree of the trunk relative to the face, that is, the extent to which the face centerline M is to be corrected according to the inclination of the trunk when the trimming centerline M′ is determined, and provides to the trimming centerline setting portion 60 the importance degree input by the user through the input means after transforming it to a value from 0 to 1. [0115] The GUI (graphic user interface) which the importance degree setting portion 80 provides to the user may be any so long as it can input the importance degree α. For example, the importance degree α may be input by providing a slide bar in a display means such as a monitor and by causing the user to move a point on the slide bar with, for instance, a mouse. When there is no input by the user, it is assumed that a default importance degree (α=0) is input. In this case, the correction according to the inclination of the trunk is not executed. [0116] The trimming centerline setting portion 60 outputs information representing the trimming centerline M′ obtained by correcting the face centerline M by the centerline correcting portion 64 to the trimming performing portion 85 . The trimming performing portion 85 sets a trimming area (the part of the image in the dotted frame in FIG. 21C ) which is laterally symmetrical about the trimming centerline M′ on the basis of the trimming centerline M′ and at the same time, cuts out the image of the obtained trimming area to obtain a trimmed image S 2 . [0117] The card making portion 90 makes an ID card with a photograph P by carrying out necessary enlargement/contraction on the trimmed image S 2 , and printing the processed image on an ID card. [0118] FIG. 22 is a flowchart for illustrating the processing in the ID card making center 100 of the ID card issue system of the embodiment shown in FIG. 1 . As shown in FIG. 22 , when photographic images S 0 are input into the ID card making center 100 by the image input portion 10 , the face detecting portion 20 carries out on the photographic images S 0 processing for detecting a face to obtain the face image S 1 (step S 10 ) The eye detecting portion 30 detects the positions of the eyes from the face image S 1 (step S 15 ) and the trunk inclination detecting portion 50 sets the range over which an image of the shoulder is to be detected, detects the shoulders and calculates the shoulder lines on the basis of the positions of the eyes detected, as well as calculates the inclination of the trunk (the degree and the direction of the inclination) on the basis of the shoulder lines (step S 20 ). The trimming centerline setting portion 60 obtains the face centerline M and at the same time, obtains a trimming centerline M′ (steps S 25 , S 30 and S 35 ) by correcting the face centerline M according to the inclination of the image of the trunk and the degree of importance α of the trunk set by the importance degree setting portion 80 . The trimming performing portion 85 sets a trimming area which is laterally symmetrical about the trimming centerline M′ obtained by the trimming centerline setting portion 60 and cuts out the image of the obtained trimming area to obtain a trimmed image S 2 (step S 40 ). The card making portion 90 makes an ID card with a photograph P (step S 45 ) by carrying out necessary enlargement/contraction on the trimmed image S 2 , and printing the processed image on an ID card. [0119] As can be understood from the description above, in accordance with the ID card issue system of this embodiment of the present invention, the trimming centerline is obtained by correcting the centerline of the face (the reference part) according to the inclination of the trunk. Accordingly, when the trunk is not inclined relatively to the face, the trimmed image can be obtained without the face and the trunk inclined and at the same time, when the trunk is inclined relatively to the face, though an image of the face is somewhat inclined in the trimmed image, an image of the trunk is not extremely inclined in the trimmed image, whereby the trimmed image is good in balance. [0120] Further, since the centerline of the face is corrected according to the degree of importance of the trunk, a trimmed image reflecting, for instance, the user's taste can be obtained. [0121] Though, a preferred embodiment of the present invention has been described above, the image processing method and system and the computer program for the purpose need not be limited to the embodiment described above, but may be variously modified within the scope of the spirit of the present invention. [0122] For example, though in the embodiment described above, a straight line perpendicular to a straight line joining the right and left eyes is obtained as the face centerline, the middle point between the eyes, the center point of a nose and the center point of a mouth may be obtained and a straight line joining these points may be employed as the face centerline as disclosed, for instance, in Japanese Unexamined Patent Publication No. 2003-092726. [0123] Further, the methods of detecting the face, eyes, and shoulder need not be limited to the methods in the embodiment described above. For example, the user may be caused to designate the methods of detecting the face, eyes, and shoulder. [0124] Further, the method of detecting the inclination of the trunk need not be limited to that where the shoulder lines are detected. [0125] Further, the method of obtaining the trimming centerline by correcting the face centerline need not be limited to that described above where the face centerline is directly corrected so long as it can result in correction of the face centerline. For example, the outer ends of the respective right and left shoulders may be obtained so that a straight line which intersects first and second straight lines at the middle of the right and left eyes and intervenes between the first and second straight lines is obtained as the trimming centerline, the first straight line being a straight line passing through the middle between the eyes in perpendicular to a straight line joining the outer ends and the second straight line being a face centerline. In this case, the trimming centerline may be decided toward the first straight line as the importance degree of the trunk increases. [0126] Further, though the face centerline is rotated about the middle between the eyes in the embodiment described above, the face centerline may be rotated about the center of a face or the upper part of the person. Further, the face centerline may be rotated about the center of the waist when the position of the waist can be known from the height of the chair as in the automatic photograph box. [0127] Further, the objects comprise only the trunks and the faces since the objects to be processed are the photographic images in the ID card issue system of this embodiment, the image processing method and system of the present invention may be applied to trimming of the photographic images of objects comprising three or more parts, and the objects need not be limited to persons.

A trimmed image is obtained by trimming for cutting out from a photographic image obtained by taking a photograph of an object including a reference part, and one or more other part which has a common centerline with the reference part and is arranged in a direction in which the centerline of the reference part extends, an image of an area including a part or the whole of the reference part and said other part along a trimming centerline. The centerline of the reference part is obtained and the degree and the direction of inclination of said other part are detected from the photographic image. The trimming centerline is inclined by a larger angle away from the centerline toward the direction of the inclination of said other part as the degree of inclination increases.

FIELD OF THE INVENTION [0001] The instant invention relates to a wrench for use in limited access areas and areas requiring a small turning arc. BACKGROUND OF THE INVENTION [0002] There are a number of wrenches currently available that can be used to tighten or loosen a nut or headed bolt. One type of flat wrench is of a fixed size and shaped to fit a single nut or bolt, while a wrench with adjustable jaws can be used for nuts or bolts of varying sizes. Socket wrenches are also made to fit a specific nut or bolt. All of these wrenches require a turning arc that is determined by the shape of the nut or bolt. When the socket or jaws of the wrench is shaped like the nut or bolt head, a specific turning arc is needed for the wrench to be effective. For example, a square nut or bolt requires a minimum turning arc of 90° while a hexagonal nut or bolt requires a minimum turning arc of 60°. This means that the wrench must be turned at least by the minimum arc before it can be removed from the nut and reseated. In many instances the location of the nut or bolt does not provide enough space to permit the use of such wrenches. Wrenches with ratchet mechanisms are also well known, but are subject to breakage under excessive forces and can usually be rotated in only one direction. [0003] Doughty, in U.S. Pat. No. 1,355,455, teaches a ratcheted socket wrench specifically designed for use in automobiles where there is limited access to certain nuts and bolts. This wrench has two rotatable ratchet wheels, each on an opposite side of a shank. The two wheels are rotatable with the socket member and wrench head. There is a pawl associated with each ratchet wheel and a pawl releasing member for each side. When the wrench is rotated in one direction one wheel is engaged and the pawl on the other side is released. When rotated in the opposite direction the other wheel is engaged and the first pawl is released. This wrench can be use to both tighten and loosen a nut or bolt and uses a small turning arc, but the mechanism can be subject to breakage under pressure. Summers teaches a wrench designed for use on Ford automobiles in areas with very limited access. (U.S. Pat. No. 1,434,635) The bolt engaging part of the wrench is a spring loaded ratchet mechanism controlling the rotation of a socket. The wrench has a handle consisting of a long solid rod with an L-shaped configuration. The end is bent over upon itself to provide a hand grip. Additionally, the wrench head can be rotated 180° and held fast by a set screw. The combination of handle shape and two head positions enables access to tight areas. Another socket wrench designed for use in motor vehicles has a long thin flat handle with an L-shaped end portion for use as a grip and to provide leverage. The long handle provides access to tight areas. This patent teaches the use of a hexagonal socket interior and also suggests the use of a square, octagonal or fluted socket interior. (Curtis, U.S. Pat. No. 2,601,800) [0004] A wrench consisting of two pieces is taught by Faw in U.S. Pat. No. 1,504,035. A simple socket has an elongated barrel with an axial hexagonal passage and a transverse round passage. A straight handlebar of hexagonal cross section fits the axial passage tightly and the transverse passage loosely. To seat the nut the handlebar is placed in the axial passage and is rotated between the palms of the hands until the nut is screwed as tightly as possible. The handlebar is then inserted into the transverse passage providing considerable leverage to complete the tightening of the nut. In the axial position the wrench can be used in a limited space, but when it is necessary to make the nut tight, a much larger turning area is required since the transverse use requires the full area traversed by the handlebar. [0005] A novel bolt or nut head is taught by Newell et al. in U.S. Pat. No. 3,482,481. The head is frustoconical with two sets of grooves. The grooves in each set are parallel and oblique to the generatrix of the cone. One set of grooves slants to the right and the other to the left. The cooperating wrench has two ends, each with a frustoconical socket having one set of ribs, the set at one end corresponding to the right slanting grooves and the set at the other end corresponding to the left slanted grooves. One end of the wrench is used to tighten the bolt and the other to loosen it. The frustoconical shape requires the wrench to be separated only a small distance from the bolt head but the turning arc is determined by the spacing of the ribs. The wrench and bolt head must be used as a combination and neither can accommodate or be accommodated by conventional hardware. [0006] British patent No. 16,793 to Delacroix describes a rod having one end with five surfaces, each with a raised cross. The rod is used with a set of sockets to fit different sized nuts. Each socket has two notches in its upper surface. The notches cooperate with the crosses. Each cross connects the rod to the socket at a different angle which enables access to a different limited space. German patent No. 575,904 to Forst shows a socket wrench consisting of a shank with connecting means at both ends and a socket member with two sockets of different interior diameters set at right angles to each other. Each socket interior cooperates with one end of the shank. The socket not attached to the shank forms the usable part of the wrench. This wrench can only be used with nuts and bolts of sizes corresponding to the socket selected. [0007] Patent 604,812 from Great Britain describes a one piece socket wrench with a fluted socket interior specifically designed for use when the nut is so close to a wall that the socket cannot fit over the nut. A part of the exterior wall of the socket is ground off to form a sloping face. The socket is placed over the nut with the ground face adjacent to the wall or other obstruction. The nut is turned as far as possible and the socket is removed and reseated. [0008] The ratchet wrenches described above are subject to breakage under large forces while many of the other wrenches are made for specific uses and are not practical for general usage. There is a need for a wrench that can be used to tighten or loosen a nut or bolt situated in any hard to reach area and where only a small turning arc is available. There is a need for a wrench that has minimal components and can withstand the large forces often necessary to remove a nut or bolt that has been in place for a long time. There is a need for a wrench that is adaptable for nuts and bolts of different sizes and shapes and one that is inexpensive and simple to manufacture. BRIEF SUMMARY OF THE INVENTION [0009] The instant invention may provide a socket wrench for use in tight areas where there is limited access or a very small turning arc or both. The wrench may have two basic components and no moving parts. The wrench may not be damaged under the stress of normal use and may be used with nuts and bolts of various shapes. Accommodations may be made for nuts and bolts of different sizes. [0010] It is an object of the instant invention to provide a wrench that can be used where there is limited access to the site of the nut or bolt to be tightened or loosened. [0011] An object of the instant invention is to provide a wrench that can be used where there is only enough space for a small turning arc. [0012] It is another object of the instant invention to provide a wrench that is easy and inexpensive to manufacture. [0013] A further object of the instant invention is to provide a wrench with a socket that can be used with nuts and bolts of different shapes. [0014] A still further object of the instant invention is to have a wrench that can be rotated to the right or to the left as needed without adjustments or alterations. [0015] Another object of the instant invention is to provide a wrench that is strong enough to withstand considerable force without becoming damaged or distorted. [0016] A further object of the instant invention is to provide a wrench that enables resetting the handle with minimal separation of the handle from the socket. [0017] Another object of the instant invention is to provide a wrench that requires no separation of the socket from the nut or bolt while the handle is reset. [0018] A still further object of the instant invention is to have a wrench that can be used by a right-handed or left-handed person with equal ease. [0019] A wrench for use in limited access areas to tighten or remove nuts and bolts comprises a hollow cylindrical socket having vertically fluted interior walls and a handle assembly comprising a horizontal shaft and a cylindrical head fixedly attached to one end of the shaft, the head having a vertically fluted exterior to complement the fluted interior walls of the socket, and the head being insertable into the socket for driving rotation thereof by movement of the shaft through an arc. When the socket is placed over a nut or bolt and the head is inserted into the top of the socket the shaft can be rotated thereby causing the socket and the nut or bolt to be rotated with it and thereafter the head is lifted clear of the socket, returned to the starting position, and reinserted into the socket so the shaft can be rotated again, and these steps are repeated as needed to tighten or remove the nut or bolt. [0020] A wrench for use in limited access areas to tighten or remove nuts and bolts comprises a hollow cylindrical socket having fluted interior walls; a horizontal partition dividing the interior of the socket into an upper chamber and a lower chamber, the walls of the upper chamber and the fluting in the upper chamber converging inwardly toward the partition, and the walls of the lower chamber and the fluting in the lower chamber being vertical; and a handle assembly comprising a horizontal shaft and a frustoconical head fixedly attached to one end of the shaft, the head having a fluted exterior to complement the fluted interior walls of the upper chamber of the socket, and the head being insertable into the socket for driving rotation of the socket by movement of the shaft through an arc. When the socket is placed over a nut or bolt and the head is inserted into the upper chamber of the socket so that the fluted exterior of the head cooperates with the fluted interior of the upper chamber the shaft can be rotated thereby causing the socket and with it the nut or bolt to be rotated, and thereafter the head is lifted upwardly of the socket a distance sufficient only to permit the flutings to separate and the shaft to be returned to the starting position and thereafter the head is reinserted into the socket so the shaft can be rotated again, and these steps repeated as needed to tighten or remove the nut or bolt. [0021] An extension for use with a wrench of a type having a socket with fluted interior walls and a handle assembly having a head complementing the interior of the socket and affixed to one end of a shaft that comprises an upper body member having a circular recess with fluted walls dimensioned to accept the head of the handle assembly, a rod having a first end and a second end and being fixedly attached at its first end to the bottom of the upper body member at the center thereof, a lower body member being cylindrical with a fluted exterior, dimensioned to be matingly accepted within the socket, and affixed to the second end of the rod; and retention means disposed within the lower body member for retaining said lower body member within said socket. When the lower body member is inserted into and retained within the socket and the handle assembly is inserted into the upper body member the wrench can be used in areas with very limited access to tighten and loosen nuts and bolts. [0022] A handle assembly for driving rotation of a socket of a type having fluted interior walls comprises a rod having a first end and a second end and a U-shaped portion substantially near the first end, a hand grip rotatably affixed to the first end of the rod, a head being cylindrical with a fluted exterior and dimensioned to be matingly accepted within the socket affixed to the second end of the rod, and retention means disposed within the head for retaining said head within said socket. When the head is inserted into and retained within the socket and the user holds the hand grip in one had and the vertical part of the U-shaped portion of the rod in the other hand and rotates the rod, the socket is rotated thereby rotating a nut or bolt held within the socket and situated in a limited access area. [0023] A wrench for use in limited access areas to tighten or remove nuts and bolts comprises a hollow cylindrical socket having an upper portion and a lower portion, said upper portion having fluted exterior walls and said lower portion having vertically fluted interior walls and a handle assembly that comprises a horizontal shaft and a cylindrical head fixedly attached to one end of the shaft, the head having a circular recess in the underside, the recess having fluted walls to complement and cooperate with the fluted exterior walls of the upper portion of the socket, and the head being superposable onto the upper portion of the socket for driving rotation thereof by movement of the shaft through an arc. When the socket is placed over a nut or bolt and the head is superposed onto the upper portion of the socket the shaft can be rotated thereby rotating the socket and the nut or bolt and thereafter the head is lifted from the socket, returned to the starting position, and repositioned onto the socket so the shaft can be rotated again, and these steps are repeated as needed to tighten or remove the nut or bolt. [0024] Other features and advantages of the invention will be seen from the following description and drawings. BRIEF DESCRIPTION OF THE DRAWING [0025] FIG. 1 is a cutaway perspective view of one form of the device of the instant invention; [0026] FIG. 2 is a side plan view of the handle assembly; [0027] FIG. 3 is a top plan view of the handle assembly; [0028] FIG. 4 is a perspective view of a portion of the shaft and the head; [0029] FIG. 5 is a cutaway perspective view of the device of FIG. 1 with a nut; [0030] FIG. 6 is a bottom plan view of the device of FIG. 1 with a nut; [0031] FIG. 7 is a cutaway perspective view of a second embodiment of the device of the instant invention; [0032] FIG. 8 is a side plan view of a second form of the handle assembly; [0033] FIG. 9 is a top plan view of the second form of the handle assembly; [0034] FIG. 10 is a side plan view of the connecting pin; [0035] FIG. 11 is a cutaway perspective view of a third embodiment of the device of the instant invention; [0036] FIG. 12 is section through line 12 - 12 of FIG. 11 ; [0037] FIG. 13 is a side plan view of a third form of the handle assembly; [0038] FIG. 14 is a side plan view of the third form of the handle assembly with pivot pin and spring in place; [0039] FIG. 15 is an exploded view of the third embodiment of the instant invention; [0040] FIG. 16 is a top plan view of a handle assembly showing a small turning angle; [0041] FIG. 17 is a top plan view of a handle assembly showing larger turning angle; [0042] FIG. 18 is a sectional view of the second embodiment of the instant invention showing the clearing distance for the head; [0043] FIG. 19 is a sectional view of the third embodiment of the instant invention showing the clearing distance for the head; [0044] FIG. 20 is a perspective view of one additional socket; [0045] FIG. 21 is a perspective view of a second additional socket; [0046] FIG. 22 is perspective view of an extension for the head for hard to reach areas; [0047] FIG. 23 is a perspective view of an alternate handle assembly for hard to reach areas; and [0048] FIG. 24 is a perspective view of an alternate handle assembly head and socket. DETAILED DESCRIPTION OF THE INVENTION [0049] A first embodiment of the instant invention may consist of two parts, the socket 30 and the handle assembly 31 . The socket 30 , seen in FIGS. 1 and 5 , may be a hollow cylinder that may have axially fluted interior walls. The fluting 32 may provide a good grip on nuts and bolts having different shapes, i.e., square or hexagonal. An example of a hexagonal nut 36 within the socket 30 may be seen in FIGS. 5 and 6 . The handle assembly 31 may have a solid cylindrical head 33 with fluting 34 on its outer surface which may cooperate with and complement the fluting 32 of the interior of the socket 30 . The head 33 may be attached to one end of a shaft 35 . The shaft 35 may be affixed to the head 33 by welding or other means known in the art. The head 33 and shaft 35 may also be of singular construction. See FIGS. 2, 3 and 4 . The head 33 may be inserted into the top of the socket 30 to form a socket wrench. [0050] To use the wrench the socket 30 may be placed over the nut 36 or bolt (not shown) and the head 33 of the handle assembly 31 inserted into the top of the socket 30 . The shaft 35 may be rotated in one direction as far as possible, then the head 33 lifted until it may be separated from the socket 30 so the shaft 35 may be rotated to the starting position, reseated in the socket 30 and rotated again. These steps may be repeated until the nut or bolt is tightened sufficiently or removed, as needed. The smaller the available turning arc, the more often these steps must be repeated to complete the task. The fluted interior of the socket and exterior of the head may enable use of this wrench when only a very small turning arc is available. [0051] A second embodiment of the instant invention may also consist of a hollow cylindrical socket 40 and handle assembly 41 . Referring to FIG. 7 , the socket 40 may be divided into two interior compartments, an upper compartment and a lower compartment, by means of a transverse partition 46 . The interior walls of both compartments may be fluted. The fluting 42 of the upper compartment may have the same tooth size and arrangement as in the lower compartment, or it may be different, according to usage and method of manufacture. There may be a depression or opening 47 with threaded walls centrally located on the upper surface of the partition 46 . Alternatively, a threaded nut or small cylinder (not illustrated) may be welded to the center of the partition. The handle assembly 41 may also consist of a solid cylindrical head 43 with a fluted 44 outer surface and a shaft 45 . There may be a smooth bore 48 through the end of the shaft 45 and extending through the center of the head 43 . FIGS. 8 and 9 . [0052] A pin 37 having one threaded end 38 and one flattened end forming a stop 39 ( FIG. 10 ) may be a part of the wrench. The pin 37 may be inserted downwardly through the bore 48 and fastened into the opening 47 in the partition 46 by mating the threading 38 of the pin 37 with the threaded wall of the opening 47 in the partition 46 . The length of the pin 37 may be slightly greater than the sum of the thickness of the shaft 45 , the depth of the head 43 , and the depth of the upper compartment of the socket 40 . The diameter of the pin 37 may be slightly smaller than the diameter of the bore 48 so that the pin 37 may be easily inserted through the bore 48 and so that the head 43 may be smoothly moved upward and downward while the pin 37 remains fixed in the opening 47 in the partition 46 . The stop 39 of the pin 37 may be larger than the bore 48 so that the head 43 may not slip off the end of the pin 37 . The pin 37 may be used to prevent the head 43 from becoming completely disengaged from the socket 40 and so the head 43 may be quickly and accurately reinserted into the socket 40 for greater efficiency during use. [0053] In operation, the head 43 may be set into the upper compartment of the socket 40 where the fluting 44 of the head 43 and the fluting 42 of the socket 40 may be in intimate cooperation. The pin 37 may be inserted through the bore 48 and held in place by means of the treaded opening 47 . The socket 40 may be placed over the nut or bolt to be manipulated and the shaft 45 rotated as far as space may permit. The handle assembly 41 may then be lifted upward until the fluting 44 of the head 43 is no longer in cooperation with the fluting 42 of the socket 40 while the pin 37 may prevent complete separation of two components. The shaft 45 may then be rotated in the reverse direction and the head 43 lowered back into the socket 40 . These steps may be repeated as many times as necessary until the nut or bolt is as tight as desired or as loose as desired. [0054] A third embodiment of the instant invention may be the most efficient when operating in a limited space. A socket 50 may be constructed in a similar manner to socket 40 , having a partition 56 separating the interior into two compartments. There may be a threaded depression or opening 57 in the center of the upper surface of the partition 56 . The lower compartment may have fluting 59 as previously noted. However, the fluting 52 in the upper compartment may converge inwardly toward the partition 56 . See FIGS. 11 and 12 . To accommodate the converging fluting 52 in the upper compartment, the handle assembly 51 may be altered accordingly. The head 53 of the handle assembly 51 may be frusto-conical in shape and may have fluting 54 on its exterior surface to cooperate with the converging fluting 52 of the upper compartment of the socket 50 . There may be a bore 58 through the end of the shaft 55 of the handle assembly 51 and through the head 53 as seen in FIG. 13 . A pin 60 with a threaded end 61 may be disposed within the bore 58 and screwed into the threaded opening 57 in the partition 56 of the socket 50 . The socket 50 and handle assembly 51 form a wrench that is operable as described above. However, the inward sloping fluting 52 and frusto-conical head 53 , enable the user to reset the wrench by merely lifting the handle assembly 51 a very small distance above the socket 50 . This dissociates the two components sufficiently to rotate the handle assembly 51 in either direction and reinsert it into the socket 50 . These steps may be repeated as necessary and the turning arc may be as great or as small as the working space permits. The pin 60 of the third embodiment 50 need only be slightly longer than the thickness of the shaft 55 and the depth of the head 53 taken together. [0055] A small turning arc A may be seen in FIG. 16 , while a larger turning arc B is illustrated in FIG. 17 . When the straight sided socket 40 is used, the head 43 must be lifted upward a distance equal to the full depth of the head 43 , the distance C as seen in FIG. 18 , before the head 43 may be reinserted. The advantage of the alternately shaped system of the third embodiment may be evident in reviewing FIG. 19 which may illustrate the small distance D the head 53 must be lifted to disengage the two components before rotating and reseating the head 53 . [0056] To further increase the efficiency of the wrench, a compression spring 62 may surround the lower portion of the pin 60 extending beyond the bottom of the head 53 . A washer 63 may be placed against the spring 62 before the pin 60 is screwed into the threaded opening 57 in the partition 56 of the socket 50 . The pin 60 may have a flattened or enlarged stop 64 at the top so the head 53 may be restrained by the pin 60 from becoming completely separated from the socket 50 even under the tension of the spring 62 . See FIGS. 14 and 15 . [0057] To operate the wrench composed of socket 50 , handle assembly 51 , and pin 60 with the spring 62 , the components may be put together as illustrated in FIG. 15 . The socket 50 may be placed over the nut or bolt to be rotated and the shaft 55 pressed downward to engage the flutings 52 and 54 . The shaft 55 may then be rotated to the left or right as needed and through the turning distance or arc as permitted by the accessible space. When rotated as far as possible the pressure on the shaft 55 may be released so that the spring 62 forces the head 53 upward. The length of the pin 60 may be dimensioned to permit the head to be raised just far enough to disengage the fluting 54 of the head 53 from the fluting 52 of the socket 50 . The frusto-conical shape of the head 53 and the corresponding shape of the upper compartment of the socket 50 may enable a very short distance D through which the head 53 must be raised to disengage the head 53 from the socket 50 . See FIG. 19 . Once the flutings are disengaged the user may rotate the shaft in either direction as far as permitted by the available space and thereafter press the shaft 55 downward tore-engage the components. The above described steps may be repeated until the nut or bolt is tightened sufficiently or removed. [0058] It should be noted that if the socket 40 and handle assembly 41 of the second embodiment are used with the pin 37 , a spring and washer may be used also. For these components, the pin 37 , as noted above must be long enough to raise the head 44 above the socket 40 in order to disengage the flutings, with or without the assist of the spring. See FIG. 18 . [0059] The fluted socket may enable one socket to accommodate a variety of nuts and bolts of different shapes and, within limitations, different sizes. One single handle assembly may be used with more than one socket as long as the upper compartments of the sockets are of the same dimensions and have the same fluting arrangement to cooperate with the fluting of the head. The socket may then have a lower compartment with a smaller diameter to accommodate smaller nuts and bolts as seen in FIG. 20 , or a lower compartment with a larger diameter as seen in FIG. 21 to accommodate larger nuts and bolts. The wrench may be sold in combinations with one handle assembly and several sockets. There may be more than one such wrench combination to accommodate most common nut and bolt sizes. [0060] At times the nut or bolt to be rotated may be recessed in such a way that the handle assembly cannot reach into the area. An extender 65 may be used with the wrench. A typical extender 65 seen in FIG. 22 may have a female cylindrical upper member 66 of comparable dimensions as the upper compartment of the socket and having the same fluting 67 . One end of a rod 68 may be affixed to the underside of the upper member 66 and the other end of the rod 68 may be affixed to a solid cylindrical male member 69 . The male member 69 may have fluting 70 about its outer surface to cooperate with the fluting of the upper compartment of the socket. In operation, the male member 69 of the extender 65 may be inserted into the upper compartment of the socket so that the user may extend the socket into the recessed area and place it over the nut or bolt to be rotated. To insure that the socket does not separate from the extender 65 a spring loaded ball 71 or other retention means known in the art may be placed within a recess in the male member 69 to hold it in place within the socket. The handle assemblies 35 and 45 described above may be used with the extender 65 in the described manner. Handle assembly 51 may require the interior fluting of the upper member of the extender to converge downwardly so as to accommodate the head 53 , and the male member to be frustoconical in shape. [0061] When the nut or bolt to be rotated may be situated within a recess with insufficient room to permit any rotation of the handle assembly an alternate handle assembly may be used. One type of alternate handle assembly 72 may be seen in FIG. 23 . A configured rod 73 may have a U-shaped section 74 near the top. There may be hand grip 75 rotatably affixed to the top of the rod 73 . A solid cylindrical male member 76 with fluting 77 about its outer surface may be affixed to the bottom of the rod 73 . In operation, the male member 76 may be inserted into the upper compartment of the socket in the same manner as noted above for the extender 65 . To insure that the socket does not separate from the male member 76 , a spring loaded ball 78 or other retention means known in the art may be placed within a recess in the male member 76 . The combination unit may then be lowered to the site of the nut or bolt to be rotated and placed over the nut or bolt. The hand grip 75 may be held in one hand and the vertical portion 79 of the U-shaped section of the rod 73 may be held in the other hand. The rod 73 may then be rotated using both hands and the nut or bolt may be rotated with it. This alternate handle assembly 72 may also be used when a nut or bolt is resistant to rotation when only a small rotation arc is available, since the added leverage obtained by the use of two hands may provide an advantage. Also, continued rotation may be possible when using the alternate handle 72 since it may not have to be reset after each rotation. A similar alternate handle assembly with a frustoconical male member may be used with the socket 50 of the third embodiment. [0062] The various embodiments of the sockets of the instant invention may be manufactured from one single cylinder, more especially socket 30 . The other embodiments, sockets 40 and 50 may be made from one piece or they may be made from two sections welded together with the partition welded between the two sections. [0063] It may also be noted that the wrench may be made with an alternate socket 80 which may have a male member 81 as its upper section and a female member 82 as the head of the handle assembly 83 . A set of two or more sockets with different sized lower compartments may be accommodated by the same handle assembly 83 . [0064] While several embodiments of the instant invention have been illustrated and described in detail, it is to be understood that this invention is not limited thereto and may be otherwise practiced within the scope of the following claims. [0065] This parts list is for examination purposes only and should not be published with the patent. Richter Parts List [0066] 30 Socket I 31 handle assembly 32 fluting in socket 33 Head of handle assembly 34 Fluting on head 35 Shaft of handle assembly 36 Hexagonal nut 37 Pin 38 Threaded end of pin 39 stop 40 socket II 41 handle assembly II 42 fluting in socket 43 head of handle assembly 44 fluting on head 45 shaft of handle assembly 46 partition in socket II 47 threaded opening in partition 48 bore 49 — 50 socket III 51 handle assembly III 52 fluting in socket III 53 head 54 fluting on head 55 shaft of handle assembly 56 partition 57 threaded opening in partition 58 bore 59 fluting in lower compartment 60 pin 61 threaded end of pin 62 spring 63 washer 64 top of pin 65 extender 66 upper female member of extender 67 fluting on female member 68 rod 69 lower male member 70 fluting on male member 71 spring loaded ball 72 alternate handle assembly 73 rod 74 U-shaped portion of rod 75 rotatable grip 76 male head 77 fluting 78 spring loaded ball 79 vertical portion of Ushape 80 alternate socket 81 female upper portion 82 male head 83 handle assembly 84 85

A wrench compatible for use in limited access areas is made up of two components. A socket with fluted interior walls cooperates with a handle assembly consisting of a head with complementary fluting on its exterior surface attached to one end of a shaft. The head is inserted into the top of the socket and the shaft is rotated as far as the available space permits. The handle assembly is then lifted upward until the head is separated from the socket, the shaft is thereafter returned to the starting point, the head returned to the socket and rotated again. These steps are repeated until the nut or bolt is tightened or removed. The interior fluting permits the rotation of the socket by small or large increments. Additional embodiments include a spring loaded pin that connects the head of the handle assembly to the socket while assisting the head to be raised a sufficient distance for the head of the handle assembly to be rotated and reseated in the socket. Additional sockets with lower portions having different interior diameters can be used with the same handle assembly for nuts and bolts of smaller and larger diameters. An auxiliary extender and an alternate handle assembly make tight or narrow areas more accessible.

BACKGROUND OF THE INVENTION 1. Field of the Invention This invention describes products containing more than one hydroxyl functionality and in addition thereto, a polar group. 2. Description of the Art Practices It is now known from this author's work that certain polyhydric alcohols, particularly those having a geminal-bis(hydroxymethyl) functionality are highly useful for curing urethane compositions. Such work is described in the U.S. Pat. Rogier No. 4,216,343 issued Aug. 5, 1980. Such compounds are geminal-bis(hydroxymethyl) alcohols which also contain a terminal hydroxyl functionality. An example of such material is gem-bis(hydroxymethyl) octadecanol. It has been found highly desirable to use such compounds due to the high reactivity of the hydroxyl groups and the stability of the polyol. Additional work concerning such materials is shown in a series of articles from the Northern Regional Research Laboratory of the U.S. Department of Agriculture at Peoria, Ill. Representative of such materials worked on by the NRRL in obtaining 9,9(10,10)-bis(hydroxymethyl) octadecanoate esters and the corresponding acid. Such work is described by Miller and Pryde [J. Amer. Oil Chemists Soc. 54, 822A-885A (1977); ibid, 55, 469-470 (1978); U.S. Pat. No. 4,093,637]. Further disclosures of hydroformylation technology are an article entitled Obtention of De Derives Biofunctionnels found by R. Lai in Rev. Fr. Corps Gras. 17:455 (1970).b. Such compounds, however, have carboxyl groups or hydrolyzable ester groups and are thus not fully usable for wetting pigments in polyurethane coatings. Furthermore, compounds such as are disclosed in this invention are miscible with polyisocyanates used to formulate coating systems. It is, of course, necessary to have sufficient miscibility to allow the formulations of the polyhydroxy compounds of the present invention into polyurethanes. Of course, the compounds of the present invention may be utilized in any area where both a polyhydroxyl functionality and a polar group are required. Throughout the specification and claims, percentages and ratios are by weight, pressure is gauge, and temperatures are in degrees Celsius unless otherwise indicated. SUMMARY OF THE INVENTION The present invention describes polyhydroxymethyl compounds containing a polar group which have the formula: CH.sub.3 (CH.sub.2).sub.m [C(CH.sub.2 OH)X].sub.n (CH.sub.2).sub.p [C(CH.sub.2 OH)X].sub.q (CH.sub.2).sub.r [C(CH.sub.2 OH)X].sub.s (CH.sub.2).sub.t CH.sub.2 M and mixtures thereof wherein X is either hydrogen or hydroxymethyl but not mixtures thereof provided that there are at least two hydroxymethyl groups per molecule; n plus q plus s are integers the sum of which is from 1 to 3; n, q and s are 0 or 1; m through t are integers the sum of which is from 11 to 19; and M is CN. DETAILED DESCRIPTION OF THE INVENTION The present invention as previously noted deals with polyhydroxyl materials which contain a polar functional group which may be introduced into the molecule in one of several methods. The hydroxyl functionality is introduced into the molecules by utilizing an unsaturated material which is hydroformylated utilizing synthesis gas to introduce a formyl group at the site of the unsaturation. Catalysts may be selected such that a polyunsaturated material is either polyhydroformylated or is monohydroformylated. Rhodium catalysts give products which introduce the formyl group at substantially every location of unsaturation in the molecule. Whereas, cobalt catalysts introduce a formyl group only at one site of unsaturation in conjugated polyunsaturated materials. The formyl groups can then be reacted via a Tollens' reaction utilizing a strong base and two moles of formaldehyde per mole of the original formyl group to convert the formyl group directly to the geminal-bis(hydroxymethyl) structures. If, however, it is desired, the formyl group may be converted with selective catalysts such as sodium borohydride to convert the formyl group to a hydroxymethyl group. It is noted, however, that the present invention requires that if such a reaction is conducted that the intermediate aldehyde must contain more than one formyl group to ensure that a polyhydroxymethyl compound will be obtained. The starting materials which may be converted into the desired products of this invention include oleonitrile, an item of commerce. The reactions are shown in the following scheme: ##STR1## In a similar fashion, linoleonitrile can be converted into a tetrahydroxynitrile or a dihydroxy nitrile as shown in the following scheme: ##STR2## Likewise, linolenonitrile can be converted into the triformyl derivative by hydroformylation using a rhodium catalyst and synthesis gas. A tri [gem-bis(hydroxymethyl)]octadecanonitrile can be formed by reacting triformyl nitrile with excess formaldehyde and caustic. In this invention, unsaturated fatty compounds having 14-24 carbon atoms and having the above terminal polar function can be used. Similarly, 9,9(10,10)-bis(hydroxymethyl)-N,N-disubstituted octadecanamide can be obtained from oleic acid as a starting material as illustrated in the following scheme: ##STR3## A 9,9(10,10)-bis(hydroxymethyl)N,N-disubstituted octadecanamide. The value of R in the disubstituted amide above for example can be dimethyl, diethyl, diphenyl, dibutyl, piperidene or morpholine. Again, where oleic acid is used as an example and non-conjugated linoleic and linolenic acids can be used as well as the unsaturated amides. It is also been determined that one particular ester of oleic acid may be converted very usefully through the use of isobutylene to give the tertiary butyl ester denominated as t-butyl 9,9(10,10)-bis(hydroxymethyl) octadecanoate. The t-butyl esters of linolenic and linoleic acids are also employed. Another class of compounds are noted as starting materials for containing the nitrile, amide or ester functionality which are reacted with synthesis gas to obtain the formyl group in more than one position in the molecule. In this case, oleic acid or oleyl alcohols are no longer sufficient and linoleyl or linolenyl acid or alcohol must be the starting material to ensure that there is more than one site of unsaturation. The formyl groups, which will be two or three according to the generic formula given herein, may be reduced with sodium borohydride to obtain, for instance, 9(10), 12(13) di-hydroxymethyloctadecanonitrile, amide or the tertiary butyl ester of the starting acid. It should be noted herein that the sum of m through t in the generic formula given in the Summary of the Invention, has a value of 11 through 19; that n plus q plus s are 1 through 3; n, q, and s are 0 or 1, preferably such that the sum of m through t is from 13 to 17 and that m and t are each 3 or greater. It is further preferred that m and t each have a value of 4, 5 or 6 or greater. It is also a preferred situation where q is 1 and n and s are each 0. It is again emphasized that at least two hydroxymethyl groups must be present on each molecule. This requirement may be satisfied by the two substituents being in a geminal configuration or by placing two hydroxymethyl groups on separate carbon atoms in the backbone. R is defined as an organic moiety which cause the amide to be tertiary. Suggested values for R are those having from 1 to 4 carbon atoms such as methyl, ethyl, propyl, butyl, secbutyl or compounds such as morpholine, piperidine, hydroxypropyl, hydroxyethyl or mixtures thereof. To conduct the synthesis gas reaction, hydrogen and carbon monoxide are added in a closed vessel at temperatures of from 100 to 150 degrees C. The hydrogen and carbon monoxide may be maintained conveniently at from ratios of 1.5:0.5 to about 0.5:1.5 molar ratio to one another. It is noted that the ratio is not critical so long as the pressure is maintained in the reaction vessel by the component gases and that the amount of hydrogen is not so great as to substantially reduce the unsaturated starting materials. In practice, the hydroformylation with the synthesis gas is conducted at from about 90 degrees C. to about 170 degrees C., preferably from 110 degrees C. to about 130 degrees C. Above the higher temperatures described above, increased amounts of unwanted by-products are formed in the reaction mixture. The pressure conditions are maintained in this sealed system at from about 20 to about 500 atmospheres, preferably from about 30 to about 100 atmospheres absolute during the hydroformylation. Conventional cobalt catalyst may be employed to obtain a single formyl group, but it is not desired for the polyunsaturated compounds due to reduction of the unsaturation. Conveniently, however, the practical catalyst to use during the synthesis gas reaction is rhodium. The rhodium may be in any convenient form such as rhodium metal, rhodium oxide, and various other rhodium salts such as rhodium chloride, rhodium dicarbonyl chloride dimer, rhodium nitrate, rhodium trichloride and other similar materials. The rhodium catalyst is also best utilized with a ligand such as trisubstituted phosphine or trisubstituted phosphite. The term trisubstituted includes both alkyl and aryl compounds and the substituted compounds of alkyl and aryl compounds. A particularly valuable ligand for the rhodium carbonyl hydride is triphenylphosphite or triphenylphosphine in that both compounds are particularly useful in minimizing migration of the double bond thereby avoiding a large number of isomers with respect to the formyl group. In general, triarylphosphines or triarylphosphites may be used for this purpose in the formation of the rhodium carbonylhydride ligand. In addition, the foregoing materials are extremely valuable in minimizing the undesired saturation of the double bond or the reduction of the formyl group. As was previously noted, materials such as sodium borohydride may be utilized to reduce the formyl group to a hydroxymethyl group thereby obtaining desired compounds of the invention. However, in most cases it is desirable to convert the formyl group via the Tollens' reaction completely to the gem-bis(hydroxymethyl) structure. Such is done by utilizing two moles of formaldehyde per formyl group and also utilizing a strong base as a reactant. Should it be desired from some reason, weak base and one mole formaldehyde may be used to obtain the hydroxymethyl formyl compound which may be utilized for various purposes including subsequent reduction of the formyl group to give the gem-bis(hydroxymethyl) variety of the claimed compounds. In either case, excess amounts of formaldehyde due to its inexpensive nature are utilized up to 1.5 preferably up to 1.2 times the amount of formaldehyde actually required to obtain the hydroxymethyl formyl or the gem-bis(hydroxymethyl) compounds. A convenient manner of adding the formaldehyde and conducting the Tollens' reaction is by using a methanol solution of formaldehyde. The strong bases which may be employed conveniently include sodium hydroxide, althrough potassium or calcium hydroxide may also be employed. The Tollens' reaction is conducted at a temperature of from about 0 degrees to about 100 degrees C., preferably from about 20 degrees C. to about 70 degrees C. The compounds of the present invention are most likely to be utilized to form urethanes with polyisocyanates. A substantial advantage in the present invention is that polar groups introduced into the molecule enhance miscibility of the respective urethane forming components. Another significant advantage is the wetting ability of the polar groups which allow for the introduction of pigments such as organic or inorganic pigments including titanium dioxide, chrome yellow, calcium or barium Lithol, phthocyanines and oxide pigments thereby providing urethane coatings with a high pigment carrying capability. The following are suggested embodiments of the present invention. EXAMPLE I Preparation of formyloctadecanonitrile (FON) Into a 1 liter, 316 SS autoclave equipped with stirrer and heat exchange coil is placed 617 grams of olenitrile, 3.0 grams of 5 percent rhodium on aluminum (Englehardt Industries) and 3.2 grams of triphenylphosphite. The autoclave is flushed with nitrogen then pressurized with carbon monoxidehydrogen (1:1) to 1080 psig. The temperature is increased to 127-133 degrees C. and maintained from 3.3 hours with a CO--H 2 pressure of 970-1080 psig. At this point a GC analysis indicated complete reaction of oleonitrile with the formation of FON. The reaction was cooled, the pressure vented and the product filtered. The yield of FON is 681. Rhodium is removed from the product by vacuum distillation. EXAMPLE II Preparation of gem-bis(hydroxymethyl)octadecanonitrile (BHMON) Into a 3 liter, glass reaction flask is placed 762 grams (2.60 moles) of formyloctadecanonitrile, 321 grams (5.84 moles) of a 54.6 percent solution of formaldehyde in methanol (Methyl Formcel, a product of Celanese Chemical Company), and 6.6 milliliters of 40 percent solution of sodium hydroxide in water. The temperature of the system is maintained at 40 degrees C. for 36 minutes then increased to 50 degrees C. Then a 40 percent solution of sodium hydroxide in water is added (25 minutes) at a rate of 5.3 milliliters/minutes until a total of 297 grams is added, including the 6.6 milliliters initially added. Temperature is maintained at 45-50 degrees C. throughout the addition and then held at 50 degrees C. for an additional 2 hours. The reaction mixture was cooled to 16 degrees C. and 27.9 grams of a 12 percent solution of sodium borohydride in 43 percent sodium hydroxide is added. The reaction temperature is maintained between 16-27 degrees C. for 20 minutes. The reaction mixture is stripped under vacuum at 49 degrees to remove methanol and water. The residual product is washed at 54 degrees C. with 500 milliliters of water plus 100 milliliters of saturated sodium sulfate solution. The upper organic phase is separated and washed successively with 500 milliliters of 0.1 N sodium hydroxide solution and 4X with 500 milliliters portions of water. The product is finally dried in vacuum (1 mm Hg) at 70 degrees C. The yield of crude BHMON was 832 grams. EXAMPLE III Preparation of 9(10), 12(13)-diformyloctadecanonitrile Hydroformylation of 9,12-linoleonitrile was carried out similar to conditions described in Example I, except that the CO--H 2 pressure is maintained at 2000 psig. EXAMPLE IV Preparation of 9(10), 12(13)-bis(hydroxymethyl)octadecanonitrile Into a solution of 8.86 grams of 9(10), 12(13)-diformyloctadecanonitrile (containing about 47 percent 9(10)-formyloctadecanonitrile) in 8.3 grams of isopropyl alcohol at 25 degrees C. is added 0.77 grams of sodium borohydride over a period of 5 minutes. After 4 hours at 28 degrees, additional sodium borohydride (9.24 grams) is added. After 44 minutes the reaction is worked up by addition of 5 milliliters acetone, distillation of the volatiles in vacuo. The residue is dissolved in a mixture of ether-water and the ether layer is washed with water. Evaporation of the ether yielded 7.60 grams of 9(10), 12(13)-bis(hydroxymethyl)octadecanonitrile containing some 9(10)-hydroxymethyloctadecanonitrile. Identification of the products was made by I.R., NMR and GC-MS. EXAMPLE IV Preparation of 9(10), 12(13)-bis(hydroxymethyl)octadecanonitrile Into a solution of 8.86 grams of 9(10), 12(13)-diformyloctadecanonitrile (containing about 47 percent 9(10)-formyloctadecanonitrile) in 8.3 grams of isopropyl alcohol at 25 degrees C. is added 0.77 grams of sodium borohydride over a period of 5 minutes. After 4 hours at 28 degrees, additional sodium borohydride (0.24 grams) is added. After 44 minutes the reaction is worked up by addition of 5 milliliters acetone and distillation of the volatiles in vacuo. The residue is dissolved in a mixture of ether-water and the ether layer is washed with water. Evaporation of the ether yielded 7.60 grams of 9(10), 12(13)-bis(hydroxymethyl)octadecanonitrile. Identification of the products is made by I.R., NMR and GC-MS. EXAMPLE VI Thermoplastic and thermosetting polymers are prepared as shown in the table. TABLE I______________________________________NCO TerminatedPrepolymer Curative Split tear1 equivalent 0.95 equivalent (psi)______________________________________A. BHON/PM 1000 BHON/80 1344 4:1 MDI 1:2B. BHON/PM 1000 1,4 BD/BHON/C-20 triol 1288 4:1 MDI 8:2:1______________________________________ These products show exceptional split tear strength. BHON is used to indicate 9(10) gem-bis(hydroxymethyl) octadecanonitrile. MDI is methylene diisocyanate and PM 1000 is PolyMeg 1000 a polyoxytetramethylene glycol. The ratios are in equivalents. BD indicates 1,4 butane diol and C-20 triol is 9(10) gem-bis(hydroxymethyl) octadecanol. A is a thermoplastic elastomer and B is a thermosetting elastomer.

The present invention deals with obtaining fatty alcohols which have polar groups located on the molecule. The fatty alcohols and polyhydric and present excellent vehicles for wetting pigments in coating compositions and paints.

BACKGROUND OF THE INVENTION 1. (Field of the Invention) The present invention relates to a method of manufacturing a resin-sealed type semiconductor device and, more particularly, to a method of the resin sealing by melting and injecting a resin tablet in a mold. 2. (Description of Related Art) The sealing a semiconductor device with a resin is accomplished by using a resin molding machine. This resin molding machine is set with top and bottom forces to form a cavity portion, which is filled with a molten resin by injection. This sealing resin is prepared by forming thermoset resin powder into a cylindrical tablet shape. The bottom force has a pot portion to be charged with the sealing resin; a plunger for pressing and injecting the charged resin onto a cull portion of the top force; and runner portions for guiding the molten resin into the cavity portion. Moreover, the top and bottom forces are individually equipped with heaters for heating and melting the sealing resin. By using the resin molding machine thus constructed, a lead frame on which a semiconductor element is mounted and to which wire bonding is performed is clamped by the top and bottom forces and by injection-molding of the sealing resin the resin-sealed type semiconductor device is fabricated. This fabrication method will be described in more detail in the following. In the resin injecting portion of the resin molding machine, the plunger is moved downward to an original position, and the space defined by the top face of the plunger and the side wall of the pot portion is charged with the resin tablet. Then, the top and bottom forces are hydraulically clamped. Next, the plunger is moved upward to press the resin tablet onto the cull portion. The injected resin flows through the runner portions into the cavity portion so that the cavity portion is wholly charged with the sealing resin. After lapse of a predetermined time period, the sealing resin is hardened, and the mold is opened to part the sealing resin of the molded piece, the cull portion and the runner portions, thus ending a series of resin molding steps. If necessary, a cleaning step of the mold surfaces may be added. In a conventional method, the process is transferred to the pressure molding step immediately, continuously after the resin molding machine has been charged with the resin tablet. The fabrication method of the prior art involves following defects. First of all, bonding wires for connecting the bonding pads of a semiconductor element mounted on the island of the lead frame to the inner leads are usually stretched straight when viewed from above but may be greatly curved by the fluid resistance of the sealing resin to cause short-circuit failures. Moreover, the corner portions near the gates of the cavity surfaces of the bottom force always contacts with the new sealing resin flowing through the runners so that they are liable to be blotted with low-molecular weight components of the sealing resin, wax and resin components of unreacted hardening agent or the like. This appears as mold blots and causes uneven surfaces of molded pieces, semiconductor devices, resulting in appearance defect of the products and marking defect. Blotted mold causes another following problem at the mold parting time. In the parting operation, either of the top and bottom forces is moved relatively apart from each other to open the mold. When the bottom force is moved downward, for example, the ejector pins of the force are simultaneously projected out to part the hardened resin from the top force. Next, when the bottom force drops to its bottom dead center, i.e., the knock-out position, the ejector pins of the bottom force are projected out to separate the sealing resin from the bottom force. In existing fabrication methods, however, the ejector pins are not uniformly raised even when the molded piece is pushed by the ejector pins. As a result, a uniform parting operation cannot be effected to leave the resin in the bottom force or break the resin at the runner portion. SUMMARY OF THE INVENTION An object of the present invention is to provide a resin-sealed type semiconductor device manufacturing method which can effect injection and parting of a sealing resin easily. Another object of the present invention is to provide a resin-sealed type semiconductor device manufacturing method which can effect the resin sealing without any large deformation of the bonding wires. The present invention is based upon a new knowledge that the above-mentioned defects of the prior art are caused because of unsufficient melting of the resin tablet before the injection. Since the injected resin is not sufficiently melted, it has a high molten viscosity and an incomplete progress of the hardening reaction. The present invention is characterized in that the viscosity of the sealing resin is dropped to improve the fluidity by heating the charged resin tablet for a predetermined time period before the injection. According to the present invention, the resin tablet is applied to the cull portion and held in a slightly deformed state under a condition of stopping movement of the plunger for a predetermined time period so that the injection may be effected after the resin tablet is heated by the heats coming from the top and bottom forces. While the deformed state is held, the cylindrical side of the resin tablet and the inner wall of the pot portion are close contact with each other so that the contact area between the resin tablet and the mold surface is maximized to accomplish the heating efficiently. The viscosity of the injected resin is decreased by the sufficient heating so that the bonding wires are hardly deformed by the flow of the injected resin and the parting from the mold is facilitated. The time period for the heating at the deformed state and at a condition of stopping vertical movement of the plunger depends upon the kind and amount of the sealing resin and is restricted by the time period required for the injection and the fluidity of the resin. Thus, the heating time period is preferably 5 sec or more and 20 sec or less when the thermoset resin to be molded at about 175° C. for the semiconductor device has a spiral flow value of 50 to 120 cm, the value indicating its fluidity, and a gelling time period of 10 to 50 sec. The especially suitable value for the heating is about 10 sec. The process for manufacturing the resin-sealed type semiconductor device according to the present invention can be realized merely by changing the sequences for the injection while requiring neither any drastic change of the ordinary resin molding machine nor any design change and any addition of a preheater for the sealing resin. BRIEF DESCRIPTION OF THE DRAWINGS The above-mentioned and other objects, features and advantages of the present invention will become more apparent by reference to the following detailed description of the invention taken in conjunction with the accompanying drawings, wherein: FIGS. 1A to 1D show a first embodiment of the present invention and are partially sectional views of a resin injecting portion, illustrating individual fabricating steps; FIGS. 2A to 2C show a second embodiment of the present invention and are partially sectional views of a resin injecting portion, indicating individual fabricating steps; FIGS. 3A and 3B are timing charts showing the movement of the bottom force and the plunger of the first embodiment and the second embodiment according to the present invention, respectively; and FIG. 4 is a section showing a mold for illustrating the parting of the sealing resin. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A fabrication method of a first embodiment according to the present invention will be described in the following with reference to FIG. 1. In the present embodiment, a sealing resin to be used is an epoxy resin, and four resin tablets having a diameter of 13 mm and a height of 11 mm are used for one mold set. This mold has top and bottom forces which are heated in advance at 180° C. Each lead frame is mounted with eight semiconductor elements having a size of 4 mm×15 mm. Two lead frames are set in the cavity of the mold, and simultaneous injections from four cull portions are performed. One of these cull portions and its vicinity are shown in FIG. 1. First of all, as shown in FIG. 1A, a pot portion 5, which is formed in a bottom force 2 and fitted with a plunger 6, is charged with a tablet-shaped sealing resin 7 on the plunger 6. Then, a top force 1 and the bottom force 2 are hydraulically clamped at their not-shown portions. When resin tablet 7 is charged, there is a clearance between the side faceof the cylindrical contour of the tablet and the inner wall of the pot portion 5, and there is also a space above its top face because of the provision of the cull portion. Only its bottom face is in contact with thetop face of the plunger 6. At this stage, therefore, the heat received fromthe bottom force 2 through the plunger 6 is remarkably restricted. Next, as shown in FIG. 1B, the plunger 6 is raised to bring the sealing resin 7 into contact to the cull portion 3 of the top force 1 and to squash its upper part, and is then stopped and left as it is for a predetermined time period while mashing the sealing resin 7 slightly. As aresult of this mashing step, the sealing resin has the side of the sealing resin is in close contact with the inner wall of the pot portion 5 and thetop face is in close contact with the cull portion 3 over a rather extendedarea. Thus, the sealing resin 7 is sufficiently heated by the heat coming from the top and bottom forces. Next, as shown in FIG. 1C, the rise of the plunger 6 is restarted to compress the sealing resin 7 so that the resin 7 melts to flow into runnerportions 4. Next, as shown in FIG. 1D, the injection is completed by raising the plunger 6 further to feed the sealing resin 7 into the not-shown cavity portions. In this state, the sealing resin 7 stops flowing, and its hardening progresses. The parting and ejection of the hardened resin will be described with reference to FIG. 4. Cavity portions 9 on the both sides of the cull portion 3 are also shown in FIG. 4. First of all, the bottom force 2 is moved downward. Simultaneously with this, the ejector pins 10 of the top force 1 are pushed to part the hard sealing resin 7 from the top force 1. When the bottom force 2 drops to its bottom dead point, in which it is to be knocked out, the ejector pin 11 of the bottom force 2 are pushed to part the hard sealing resin 7 from the bottom force 2 altogether with its portions filling up the spaces of the cavity portions 9, the runner portions 4 and the cull portion 3. Thus, the sealing resin 7 is ejected from the mold together with the semiconductor elements (not-shown) which are resin-sealed on a lead frame 8. Next, the timing operations of the manufacturing process of FIG. 1 will be described in detail with reference to FIG. 3A. In FIG. 3A, the ordinate plots the operation strokes of the bottom force and the plunger, and the abscissa plots the required time period. This time period indicates the lapse from a mold clamping start time T 1 . After the charge of the resin tablet 7, the bottom force 2 starts rising simultaneously with the start of the mold clamping. After 5 sec, the bottom force 2 rises 40 mm from the original point D 0 to reach a speed changing point P 1 . After 7 sec, the bottom force 2 rises 45 mm to complete the mold clamping.After 10 sec (at the injection start time T 2 ), the plunger 6 starts torise. After 11 sec (T 3 ), the plunger 6 rises 2 mm from the origin P 0 to start the abutment of the sealing resin 7 against the cull portion 3, so that the plunger 6 reaches a tablet abutment position P 6 to stop during 5 sec. In other words, the heating is accomplishedin 5 seconds. After 16 sec (11 sec+5 sec), the injection is restarted at T 4 , so that the plunger 6 rises 12 mm to reach an injection end pointP 4 . After 23 sec, the operation comes an injection end T 5 . The sealing resin is hardened in that position. After 127 sec, the hardening ends to start the parting of the mold at T 6 . Then, the bottom force 2starts descending. After 129 sec, the bottom force 2 descends by 5 mm to pass the speed changing point P 1 . After 134 sec, the bottom force 2 moves down by 40 mm from P 1 to return the original point D 0 . After 140 sec, the rise of the plunger 6 and the fall of the bottom part 2are simultaneously started. As a result, the plunger 6 rises 14 mm to reachthe face position P 3 of the bottom force whereas the bottom force 2 reaches a knock-out position P 2 . Then, these two members stop for 1 sec. so that the knock-out is accomplished by the ejector pins 11. After 142 sec, the bottom force 2 starts to rise to return to the original pointD 0 at a time after 143 sec, whereas the plunger 6 drops from the original point P 0 to a head lowering position P 5 at a level of 2.5 mm from the original point P 0 to release the adhesion of the resin from the cull portion. After this, the plunger rises again to the face position P 3 of the bottom force until it returns to the originalpoint P 0 at a time after 147 sec, thus ending one injection process. Thus, the plunger stops for the heating for 5 sec. from the abutment start T 3 to the injection restart T 4 within the time period of 13 sec.from the injection start T 2 to the injection end T 5 . Generally, the stopping period of the plunger (from T 3 to T 4 ) is 5 sec. or more and 20 sec. or less. The fabrication process of a second embodiment according to the present invention will be described with reference to FIG. 2. The conditions in this description are identical to those of the first embodiment. As shown in FIG. 2A, the tablet-shaped sealing resin 7 put in the pot portion 5 is brought into abutment against the cull portion 3 of the top force 1 by therise of the plunger 6. In this state, the top force 1 and the bottom force 2 are clamped. In other words, the plunger 6 starts to rise at the timing of the clamping start, and the sealing resin 7 has already been heated from both of the top and bottom forces at the end of the mold clamping. Next, as shown in FIG. 2B, the sealing resin 7 is melted by the rise of the plunger 6 and has the injection starts to flow into the runner portions 4. Next, as shown in FIG. 2C, the plunger 6 is further raised to feed the sealing resin 7 into the cavity portions (not shown) and harden it therein. The subsequent parting and draw of the sealing resin are similar to those described with reference to FIG. 4. In the present embodiment, the abutment against the cull portion 3 by the plunger 6 is carried out simultaneously with the molding clamping. Despite of this fact, the sealing resin 7 may have already been raised above the top face of the bottom force 2 before the mold clamping and adjustment may be made so that the upper face of the sealing resin abuts against the cull portion3 after the mold clamping. Next, the timing operations of the fabrication process of FIG. 2 will be described in the following with reference to FIG. 3B. The numerical valuesfor this description are similar to those of FIG. 3A. In the present embodiment, the mold clamping start T 1 and the injection start T 2 occur simultaneously, and the rises of the plunger 6 and the bottom force 2 are started simultaneously with the start of the mold clamping. Accordingly, the timings of the abutment start T 3 and the injection restart T 4 becomes earlier to prolong the hardening time till the mold opening start T 6 . Table 1 shows, for the conventional method and the first and second embodiments of the present invention: the numbers of shots (i.e., injections) of defective parting per 100 shots (with additional notes of the time periods of interruption of operation due to the defective parting); the numbers of defectives due to curve of the bonding wires of the moldings per 100 shots for the lead frame having eight semiconductor elements mounted thereon; and the sealing yields (%) separately totaled. Moreover, in the righthand column, the number of shots in a cycle from a mold cleaning to the next cleaning are shown. It could be found that the numbers of defective parting and defectives are drastically reduced according to the present invention, that the filling yields are remarkablyincreased, and that the mold blotting is reduced to suppress the cleaning frequencies. TABLE 1__________________________________________________________________________ Number of Defective Parting (Interruption Number of Cleaning Time of Operation by Wire Defect Sealing Frequency of the Defective Parting) by Shot Yield % Mold (Force)__________________________________________________________________________Prior Art 23/100 315/(8 × 100) 55 1/590 Shots (2.5)First Embodiment 1/100 7/(8 × 100) 95 1/1620 Shots (0.5)Second Embodiment 0/100 2/(8 × 100) 98 1/2360 Shots (0)__________________________________________________________________________ Although the present invention has been described with reference to the specific embodiments, it is not meant to be construed in a limiting sense.Various modifications of the disclosed embodiments, as well as other embodiments of the invention, will become apparent with reference to the description of the invention. It is therefore contemplated that the appended claims will cover any modifications as fall within the true scopeof the invention.

A method of manufacturing a resin-sealed type semiconductor device including heating sealing resin at a state of contacting the resin to a cull portion by means of a plunger during a predetermined period at the time the plunger stops its movement. The sealing resin is sufficiently heated to become low viscosity melting state. Thereafter, the melting state resin is injected into a cavity where resin sealing is performed.

CROSS-REFERENCE TO RELATED APPLICATIONS [0001] This application claims the benefit of U.S. Provisional Application No. 61/110,234, filed Jan. 30, 2015; which is incorporated herein by reference in its entirety, including any drawings. BACKGROUND [0002] 1. Field [0003] The embodiments discloses herein related chromium compositions and methods of using same for the treatment and/or prevention of diabetic retinopathy. The present application is based, in part, on the surprising discovery that chromium histidinate (“CrHis”) can be used to treat and/or prevent diabetic retinopathy. CrHis may also be used to reduce levels of retina malondialdehyde and glycosylated hemoglobin and/or decrease oxidative stress and lipid oxidation in the retina. [0004] 2. Description of Related Art Diabetic Retinopathy [0005] Diabetic retinopathy is a common diabetic eye disease and a leading cause of blindness in working-age population. The pathophysiology of diabetic retinopathy is complex and multifactorial. The pathogenic process involves intricate interactions between oxidative stress and hyperglycemia. [0006] In a high energy-demanding tissue such as retina, the regulation of glucose uptake and its utilization is important for the maintenance of normal retinal function. Glucose uptake is regulated by glucose transporter proteins (GLUTs) and all mammalian cells contain one or more members of this GLUT protein family. Glucose uptake into retina cells occurs across the blood-retinal barrier. Chromium [0007] Chromium is an essential trace element. The essentiality of chromium in the diet was established in 1959 by Schwartz. (Schwartz, “Present Knowledge in Nutrition,” page 571, fifth edition (1984, the Nutrition Foundation, Washington, D.C.)). Chromium is essential for optimal insulin activity in all known insulin-dependent systems (Boyle et al. (1977) Southern Med. J. 70:1449-1453). Chromium depletion is characterized by the disturbance of glucose, lipid and protein metabolism and by a shortened lifespan. Insufficient dietary chromium has been linked to both maturity-onset diabetes and to cardiovascular disease. [0008] Dietary supplementation of chromium to normal individuals has been reported to lead to improvements in glucose tolerance, serum lipid concentrations, including high-density lipoprotein cholesterol, insulin and insulin binding. (Anderson (1986) Clin. Psychol. Biochem. 4:31-41). Supplemental chromium in the trivalent form, e.g. chromic chloride, is associated with improvements of risk factors associated with adult-onset (Type 2) diabetes and cardiovascular disease. Chromium supplementation has been shown to reduce hyperglycemia, as well as promote weight loss, as described in U.S. Pat. Nos. 5,929,066, 6,329,361, and 6,809,115, which are each hereby incorporated by reference in their entirety. In a clinical study, Anderson et al. ( Metabolism (1987) 36(4):351-355, 1987), chromium supplementation was shown to alleviate hypoglycemic symptoms and raise serum glucose levels out of the hypoglycemic range. In another study, chromium supplementation to overweight children with Type 1 diabetes did not result in any cases of hypoglycemia (May, 2007). In yet another study, chromium supplementation to adults with Type 1 diabetes did not result in any cases of hypoglycemia; and allowed a 50% reduction in insulin dose (Ravina et al. (1995) J. Trace Elements in Experimental Med. 12:71-83). [0009] The principal energy sources for the body are glucose and fatty acids. Chromium depletion results in biologically ineffective insulin and compromised glucose metabolism. Under these conditions, the body relies primarily upon lipid metabolism to meet its energy requirements, resulting in the production of excessive amounts of acetyl-CoA and ketone bodies. Some of the acetyl-CoA can be diverted to increased cholesterol biosynthesis, resulting in hypercholesterolemia. Diabetes mellitus is characterized in large part by glycosuria, hypercholesterolemia, and often ketoacidosis. The accelerated atherosclerotic process seen in diabetics is associated with hypercholesterolemia. (Boyle et al. (1977) Southern Med. J. 70:1449-1453). [0010] Chromium functions as a cofactor for insulin. It binds to the insulin receptor and potentiates many, and perhaps all, of its functions. (Boyle et al. (1977) Southern Med. J. 70:1449-1453). These functions include, but are not limited to, the regulation of carbohydrate and lipid metabolism. (Schwartz, “Present Knowledge in Nutrition,” page 571, fifth edition (1984, the Nutrition Foundation, Washington, D.C.)). The introduction of inorganic chromium compounds per se into individuals is not particularly beneficial. Chromium must be converted endogenously into an organic complex or must be consumed as a biologically active molecule. Only about 0.5% of ingested inorganic chromium, however, is assimilated into the body. (Recommended Daily Allowances, Ninth Revised Edition, The National Academy of Sciences, page 160, 1980). Only 1-2% of most organic chromium compounds are assimilated into the body. [0011] U.S. Pat. Nos. 4,315,927 and Re. 33,988 disclose that when selected essential metals, including chromium, are administered to mammals as exogenously synthesized coordination complexes of picolinic acid, they are directly available for absorption without competition from other metals. Describes therein are compositions and methods for selectively supplementing the essential metals in the human diet and for facilitating absorption of these metals by intestinal cells. These complexes are safe, inexpensive, biocompatible, and easy to produce. The exogenously synthesized essential metal coordination complexes of picolinic acid (pyridine-2-carboxylic acid) have the following structural formula: [0000] [0000] wherein M represents the metallic cation and n is equal to the cation's valence. For example, when M is Cr and n=3, then the compound is chromic tripicolinate. Other chromium picolinates disclosed include chromic monopicolinate and chromic dipicolinate. [0012] The U.S. Recommended Daily Intake (RDI) of chromium is 120 μg. U.S. Pat. No. 5,087,623, the entire contents of which are hereby expressly incorporated herein by reference, describes the administration of chromic tripicolinate for the treatment of adult-onset diabetes in doses ranging from 50 to 500 μg. U.S. Pat. No. 6,329,361, the entire contents of which are hereby expressly incorporated herein by reference, discloses the use of high doses of chromic tripicolinate (providing 1,000-10,000 μg chromium/day) for reducing hyperglycemia and stabilizing the level of serum glucose in humans with Type 2 diabetes. U.S. Pat. Nos. 5,789,401 and 5,929,066, the entire contents of which are hereby expressly incorporated herein by reference, disclose a chromic tripicolinate-biotin composition and its use in lowering blood glucose levels in humans with Type 2 diabetes. [0013] U.S. Pat. Nos. 5,087,623; 5,087,624; and 5,175,156, the entire contents of which are hereby expressly incorporated herein by reference, disclose the use of chromium tripicolinate for supplementing dietary chromium, reducing hyperglycemia and stabilizing serum glucose, increasing lean body mass and reducing body fat, and controlling serum lipid levels, including the lowering of undesirably high serum LDL-cholesterol levels and the raising of serum High Density Lipid (HDL)-cholesterol levels. U.S. Pat. Nos. 4,954,492 and 5,194,615, the entire contents of which are hereby expressly incorporated by reference, describe a related complex, chromic nicotinate, which is also used for supplementing dietary chromium and lowering serum lipid levels. Picolinic acid and nicotinic acid are position isomers having the following structures: [0000] [0014] Nicotinic acid and picolinic acid form coordination complexes with monovalent, divalent and trivalent metal ions and facilitate the absorption of these metals by transporting them across intestinal cells and into the bloodstream. Chromium absorption in rats following oral administration of CrCl 3 was facilitated by the non-steroidal anti-inflammatory drugs (NSAIDs) aspirin and indomethacin. (Davis et al. (1995) J. Nutrition Res. 15:202-210; Kamath et al. (1997) J. Nutrition 127:478-482). These drugs inhibit the enzyme cyclooxygenase which converts arachidonic acid to various prostaglandins, resulting in inhibition of intestinal mucus formation and lowering of intestinal pH which facilitates chromium absorption. [0015] There remains a constant need for effective treatments of diabetic retinopathy and associated conditions. The present embodiments disclosed herein address this need by providing a safe, inexpensive, drug-free therapeutic agent, and methods of administering the same. Different forms of chromium exhibit different and unpredictable absorption and activity profiles in vivo. In order for a chromium complex to exert a biological effect in vivo, it must (1) be absorbed by the body; (2) be absorbed in the right cells (tissues or organs); and (3) must be released from the complex once within the cells. The fact that a particular chromium complex may be absorbed by certain cells does not necessarily guarantee a biological effect. Whether a particular form of chromium will be effectively absorbed, let alone whether the chromium will be released from the complex once absorbed to exert any physiological effect is unpredictable. SUMMARY [0016] The embodiments disclosed herein are based, in part, upon the surprising discovery that chromium and histidinate, chromium histidinate complexes, and combinations thereof possess improved therapeutic efficacy and benefits in treating and/or preventing diabetic retinopathy and associated conditions. Chromium histidinate complexes may have a greater therapeutic effect than other chromium complexes when used to treat or prevent diabetic retinopathy and its associated symptoms. See, e.g., U.S. Patent Appl. No. 2010/0009015, incorporated by reference in its entirety. [0017] Embodiments disclosed herein relate to the use of compositions comprising, consisting essentially of, or consisting of chromium and histidine, chromium histidinate complexes, chromium trihistidinate, chromium polyhistidinate complexs, or combinations thereof, including pharmaceutically acceptable salts, hydrates, solvates, or mixtures thereof for the improved treatment and/or prevention of diabetic retinopathy and related conditions, diseases, and disorders. [0018] Some embodiments comprise methods of treating and/or preventing and/or ameliorating the symptoms of diabetic retinopathy by administering chromium histidinate, chromium trihistidinate, or chromium polyhistidinate, or any combination thereof, to a patient. Some embodiments comprise methods of lowering the levels of retina malondialdehyde by administering chromium histidinate, chromium trihistidinate, or chromium polyhistidinate, or any combination thereof, to a patient in need thereof. Some embodiments comprise methods of lowering the levels of glycosylated hemoglobin by administering chromium histidinate, chromium trihistidinate, or chromium polyhistidinate, or any combination thereof, to a patient in need thereof. Some embodiments comprise methods of decrease treating and/or preventing and/or reducing oxidative stress in the retina by administering chromium histidinate, chromium trihistidinate, or chromium polyhistidinate, or any combination thereof, to a patient in need thereof. Some embodiments comprise methods of decrease treating and/or preventing and/or reducing lipid oxidation in the retina by administering chromium histidinate, chromium trihistidinate, or chromium polyhistidinate, or any combination thereof, to a patient in need thereof. [0019] Some embodiments relate to decreasing metabolic abnormalities implicated in the pathogenesis of diabetic retinopathy. In some embodiments, these metabolic abnormalities comprise increased oxidative stress, increased lipid peroxidation, hyperglycemia, and increased protein glycation. Some embodiments relate to reducing free radical oxidation of the retinal photoreceptors. Some embodiments relate to decreasing or preventing loss of lipoprotein membrane content. Some embodiments relate to decreasing or preventing the retinal capillary basement membrane from thickening. Some embodiments relate to decreasing or preventing retinal microangiopathy. [0020] Some embodiments relate to decreasing the risk of loss in visual acuity in individuals having diabetic retinopathy. Some embodiments relate to preventing loss in visual acuity in individuals having diabetic retinopathy. Some embodiments relate to reducing the degree of retinal hard exudates. Some embodiments relate to decreasing ocular glucose levels. Some embodiments relate to decreasing ocular cholesterol levels. Some embodiments relate to decreasing ocular triglyceride levels. Some embodiments relate to decreasing levels of glycosylated hemoglobin. [0021] Some embodiments relate to pharmaceutical compositions comprising one or more compositions disclosed herein, with a pharmaceutically acceptable vehicle, excipient, or diluent. For example, pharmaceutically acceptable vehicles can include carriers, excipients, diluents, and the like, as well as combinations or mixtures thereof. [0022] Some embodiments relate to co-administration with antidiabetic drugs to provide an additive effect. Some embodiments relate to co-administration with antidiabetic drugs to provide a synergistic effect. Some embodiments relate to improving an individual's carbohydrate metabolic profile. In some embodiments, a carbohydrate metabolic profile is assessed by measuring expression of insulin as well as various glucose transporter proteins. Some embodiments relate to improving insulin binding to retinal cells. [0023] In some aspects, the effective amount of chromium in the composition can be between about 5 and 2,000 micrograms. In some aspects, the chromium is selected from the group of chromium complexes consisting of chromium picolinate, chromic tripicolinate, chromium nicotinate, chromic polynicotinate, chromium chloride, chromium histidinate, chromium trihistidinate, and chromium yeasts. Preferably, the chromium comprises chromium histidinate. In some aspects, the composition comprises chromium histidinate in combination with one or more additionally chromium complexes. [0024] The present compositions can take the form of solutions, suspensions, emulsion, tablets, pills, pellets, capsules, capsules containing liquids, powders, sustained-release formulations, suppositories, emulsions, aerosols, sprays, suspensions, or any other form suitable for use. In some embodiments, the composition is topically administered to the eye. Some embodiments relate to a solid formulation. Other modes of administration useful in the methods include but are not limited to intradermal, intramuscular, intraperitoneal, intravenous, subcutaneous, intranasal, epidural, oral, sublingual, intranasal, intracerebral, intravaginal, transdermal, rectally, by inhalation, or topically, particularly to the ears, nose, eyes, or skin. [0025] In some aspects, a method for treating, preventing, or ameliorating diabetic retinopathy in a subject in need thereof, comprises identifying a subject having or at risk for developing diabetic retinopathy and administering a therapeutically effective amount of at least one chromium complex. The at least one chromium complex may consists essentially of chromium and histidine, a chromium histidinate complex, or combinations thereof. At least one chromium complex may be co-administered with a second therapeutic agent selected from the group consisting of insulin, metformin, and a chromium-insulin complex. The second therapeutic agent may be administered orally. The administering a therapeutically effective amount of at least one chromium complex may comprise administering a topical ophthalmic formulation. [0026] In some aspects, a formulation for topical ophthalmic administration comprises a therapeutically effective amount of one or more chromium complexes and at least one ophthalmically acceptable excipient. The formulation may include a second therapeutic agent selected from the group consisting of insulin, metformin, and a chromium-insulin complex. BRIEF DESCRIPTION OF THE FIGURES [0027] FIGS. 1A-1E illustrates the effect of chromium supplementation on the expression of, GLUT 1 (Panel A), GLUT3 (Panel B), insulin (Panel C), MDA (Panel D) values, and density of proteins (Panel E) in the retina tissue regions of DR rats. Data are means of quadruplets of assays and expressed as relative to control (%). Blots were repeated at least three times (n=3) and a representative blot for each is shown. Actin was included to ensure equal protein loading. Values are LS means±SE. Different letters within the retina parts indicate statistical differences among groups (p<0.05). [0028] FIG. 2 illustrates paraffin section photograph(s) of rat retina control and experimental group, control (A), CrHis alone (B), STZ+CrHis (C), and STZ alone (D) showing the histopathological changes. DETAILED DESCRIPTION Chromium [0029] As used herein, the term “chromium” refers to chromium chloride, chromium yeasts, as well as chromium complexes. Some chromium complexes useful in the embodiments disclosed herein include, but are not limited to, the following: chromium histidinate; chromium trihistidinate; chromium polyhistidinate; chromium dinicocysteinate; chromium dinicotinate tryptophan; chromium dinicotinate tyrosine; chromium dinicotinate hydroxycitrate; chromium dinicotinate cinnamate; chromium dinicotinate gallate; chromium dinicotinate 5-hydroxytryptophan; chromium dinicotinate aspartate; chromium dinicotinate glutamate; chromium dinicotinate arginate; chromium tris(tryptophan); chromium nicotinate, chromium polynicotinate; chromium picolinate; chromium monopicolinate; chromium dipicolinate; chromium tripicolinate; chromium triphenylalanine; chromium tris(tyrosine); chromium tris(hydroxycitrate); chromium tris(5-hydroxytryptophan); chromium tris(cinnamate); chromium tris(gallate); chromium complexes disclosed herein are chromium having three different carboxylate ligands. [0030] As used herein, the term “hydrophilic chromium complex” or “fast acting chromium complex” refers to a chromium complex that is charged at physiological pH, or has polar properties. Non-limiting examples of hydrophilic, fast-acting chromium complexes include chromium acetate, chromium chloride, chromium histidinate and chromium nicotinate, and the like, or any pharmaceutically acceptable salts, hydrates, solvates, or mixtures thereof. [0031] The term “lipophilic chromium complex” or “slow-acting chromium complex” refers to a chromium complex that is not charged at physiological pH, and that does not have polar properties. Chromium picolinate, and any pharmaceutically acceptable salts, hydrates, or solvates thereof, is a non-limiting example of a lipophilic, slow-acting chromium complex. [0032] The eye includes multiple parts, such as the aqueous humor, vitreous humor, and the retina. One skilled in the art would recognize that references to the “eye” and to the “retina” may include overlapping parts of the eye. [0033] In preferred embodiments, the hydrophilic chromium complex or the “fast-acting” chromium complex is chromium histidinate, chromium trihistidinate, or chromium polyhistidinate, or any combination thereof. Preferably, the lipophilic chromium complex or the “slow-acting” chromium complex is chromium picolinate. [0034] In various cases, the ligand(s) has/have the ability to bond to chromium via its carboxylate functional group as well as through pi electron-d orbital interaction. This secondary interaction between the ligand and chromium can increase the bioavailability and absorption of chromium. [0035] In some embodiments, the chromium can be in the form of complexes of trivalent chromium and at least one and no more than three tyrosine or tryptophan ligands. In specific embodiments, the chromium can be in the form of chromium complexes such as chromium (III) tris(tryptophan) and chromium (III) tris(tyrosine). [0036] In some embodiments, the chromium complexes can be complexes of trivalent chromium and one or more compounds extracted from plants. Non-limiting examples of plants from which these compounds can be extracted include plants such as genus Garcinia, Groffonia simplicifolia, cinnamon bark, gallnuts, sumac, witch hazel, tea leaves, and oak bark. For example, in some embodiments, chromium can be provided in the form of chromium hydroxycitrate, chromium hydroxytryptophan, chromium cinnamate, and chromium gallate. [0037] Preferably, the chromium is provided as a combination of chromium picolinate and chromium histidinate, or as a combination of chromium nicotinate and chromium histidinate. In other preferred embodiments, the chromium is provided as chromium histidinate. In another preferred embodiment, chromium is provided as a chromium histidinate complex. The compositions disclosed herein may consist of, consist essentially or, and/or comprise chromium histidinate complexes. [0038] While the chromium complexes aid in the absorption of chromium by intestinal cells, in some embodiments, uncomplexed chelating agents are advantageously included in the compositions to facilitate absorption of other ingested chromium as well as other metals including, but not limited to, copper, iron, magnesium, manganese, and zinc. Suitable chelating agents include histidine, any essential amino D or L amino acids, tri amino acid formulae including but not limited to, triphenylalanine, tri histidine, tri arginine, picolinic acid, nicotinic acid, or both picolinic acid and nicotinic acid. [0039] Chelating agents such as histidine, picolinic acid and nicotinic acid are available from many commercial sources, including Sigma-Aldrich (St. Louis, Mo.) (picolinic acid; catalog No. P5503; nicotinic acid; catalog No. PN4126). In some embodiments, the ratio of the chromium complex to the chelating agent in the embodiments disclosed herein can be from about 10:1 to about 1:10 (w/w), more preferably from about 5:1 to about 1:5 (w/w), e.g., 5:1, 5:2, 5:3, 5:4, 1:1; 1:2, 1:3, 1:4, 1:5, or any number in between. Alternatively, the molar ratio of chromium complex to the uncomplexed chelating agent is preferably 1:1, and can be from about 5:1 to about 1:10, e.g., e.g., 5:1, 5:2, 5:3, 5:4, 1:1; 1:2, 1:3, 1:4, 1:5, 1:6, 1:7, 1:8, 1:9, 1:10, or any number in between. The chelating agents with D or L amino acid and or with tri or mono and di forms of chromium complex with tri amino acid or one or more amino acids but not limited to chromium triphenylanine, chromium trihistidine, chromium poly phenylanine, chromium poly hisitidine, chromium polynicotinate, chromium di phenylananine, chromium di picolinic acid, chromium di hisitidine etc. [0040] Some embodiments provide methods of identifying a subject having diabetic retinopathy. Some embodiments provide methods of identifying a subject at risk of developing diabetic retinopathy. In some embodiments, identifying the subject having or at risk of developing diabetic retinopathy comprises performing blood tests, including, but not limited to testing blood glucose levels, malondialdehyde levels, anti-oxidant levels, cortisol levels, insulin levels, oxidative stress markers, oxidized fatty acids, and hemoglobin Alc. [0041] In some embodiments, identifying the subject having or at risk of developing diabetic retinopathy comprises performing eye examinations, including, but not limited to fundus photographic sets (for example, two fundus images from each eye), visual acuity testing, tonometry of the eye(s), pupil dilation and physical examination of the retina, ophthalmoscopy, slit lamp exam, gonioscopy, and optical coherence tomography (OCT). In some embodiments, the subject has symptomatic diabetes. In some embodiments, the subject has asymptomatic diabetes. [0042] Some embodiments provide methods of decreasing levels of malondialdehyde in the eye. In some embodiments, malondialdehyde levels in the eye are decreased by at least about 5%, at least about 10%, at least about 15%, at least about 20%, at least about 25%, at least about 30%, at least about 35%, at least about 40%, at least about 45%, at least about 50%, at least about 55%, at least about 60%, at least about 65%, at least about 70%, at least about 75%, at least about 80%, at least about 85%, at least about 90%, at least about 95%, at least about 98%, or at least about 99%. [0043] Some embodiments provide methods of decreasing levels of HbAlc in the eye. In some embodiments, HbAlc levels in the eye are decreased by at least about 5%, at least about 10%, at least about 15%, at least about 20%, at least about 25%, at least about 30%, at least about 35%, at least about 40%, at least about 45%, at least about 50%, at least about 55%, at least about 60%, at least about 65%, at least about 70%, at least about 75%, at least about 80%, at least about 85%, at least about 90%, at least about 95%, at least about 98%, or at least about 99%. [0044] Some embodiments provide methods of decreasing levels of oxidized lipids in the eye. In some embodiments, oxidized lipid levels in the eye are decreased by at least about 5%, at least about 10%, at least about 15%, at least about 20%, at least about 25%, at least about 30%, at least about 35%, at least about 40%, at least about 45%, at least about 50%, at least about 55%, at least about 60%, at least about 65%, at least about 70%, at least about 75%, at least about 80%, at least about 85%, at least about 90%, at least about 95%, at least about 98%, or at least about 99%. [0045] Some embodiments provide methods of improving visual acuity. In some embodiments, visual acuity is increased by at least about 5%, at least about 10%, at least about 15%, at least about 20%, at least about 25%, at least about 30%, at least about 35%, at least about 40%, at least about 45%, at least about 50%, at least about 55%, at least about 60%, at least about 65%, at least about 70%, at least about 75%, at least about 80%, at least about 85%, at least about 90%, at least about 95%, at least about 98%, or at least about 99%, using standard measures of visual acuity. [0046] Some embodiments provide compositions and methods of treating subjects with compositions that comprise or consist of a therapeutically effective amount of chromium. Some embodiments provide compositions and methods of treating subjects with compositions that comprise, consist essentially of, or consist of a therapeutically effective amount of insulin. Some embodiments provide compositions and methods of treating subjects with compositions that comprise, consist essentially of, or consist of a therapeutically effective amount of chromium and a therapeutically effective amount of insulin. For example, some embodiments provide compositions and method of treating subjects that comprises, consists essentially of, or consist of a chromium-insulin complex. Various methods of treatment are discussed below. [0047] A “therapeutically effective amount” as used herein includes within its meaning a non-toxic but sufficient amount of a compound active ingredient or composition comprising the same for use in the embodiments disclosed herein to provide the desired therapeutic effect. The exact amount of the active ingredient disclosed herein required will vary from subject to subject depending on factors such as the species being treated, the age and general condition of the subject, the severity of the condition being treated, the particular agent being administered, the weight of the subject, and the mode of administration and so forth. Thus, it is not possible to specify an exact “effective amount”. However, for any given case, an appropriate “effective amount” may be determined by one of ordinary skill in the art using only routine methods. [0048] By way of example, a “therapeutically effective amount” of the chromium disclosed herein can be, for example, 0.001 μg/kg, 0.01 μg/kg, 0.1 μg/kg, 0.5 μg/kg, 1 μg/kg, 1.5 μg/kg, 2.0 μg/kg, 2.5 μg/kg, 3.0 μg/kg, 3.5 μg/kg, 4.0 μg/kg, 4.5 μg/kg, 5.0 μg/kg, 10 μg/kg, 15 μg/kg, 20 μg/kg, 25 μg/kg, 30 μg/kg, 35 μg/kg, 40 μg/kg, 45 μg/kg, 50 μg/kg, 55 μg/kg, 60 μg/kg, 65 μg/kg, 70 μg/kg, 75 μg/kg, 80 μg/kg, 85 μg/kg, 90 μg/kg, 95 μg/kg, 100 μg/kg, 150 μg/kg, 200 μg/kg, 250 μg/kg, 300 μg/kg, 350 μg/kg, 400 μg/kg, 450 μg/kg, 500 μg/kg, 550 μg/kg, 600 μg/kg, 650 μg/kg, 700 μg/kg, 750 μg/kg, 80 μg/kg 0, 850 μg/kg, 900 μg/kg, 1 mg/kg, 1.5 mg.kg, 2.0 mg/kg, 2.5 mg/kg, 3 mg/kg, 4.0mg/kg, 5.0 mg/kg, 6 mg/kg, 7 mg/kg, 8 mg/kg, 9 mg/kg, 10 mg/kg, 15 mg/kg, 20 mg/kg, 25 mg/kg, 30 mg/kg, 35 mg/kg, 40 mg/kg, 45 mg/kg 50 mg/kg, 55 mg/kg, 60 mg/kg, 65 mg/kg, 70 mg/kg, 75 mg/kg, 80 mg/kg, 85 mg/kg, 90 mg/kg, 95 mg/kg, 100 mg/kg, 125 mg/kg, 150 mg/kg, 200 mg/kg, 250 mg/kg, 300 mg/kg, 350 mg/kg, 400 mg/kg, 450 mg/kg, 500 mg/kg, 550 mg/kg, 600 mg/kg, 650 mg/kg, 700 mg/kg, 750 mg/kg, 800 mg/kg, 850 mg/kg, 900 mg/kg, 950 mg/kg, lg/kg, 5 g/kg, 10 g/kg, or more, or any fraction in between of chromium. Accordingly, in some embodiments, the dose of chromium in compositions disclosed herein can be about 0.001 μg to about 100 g, preferably per day. For example, the amount of chromium can be 0.001 μg, 0.01 μg, 0.1 μg, 0.2 μg, 0.3 μg, 0.4 μg, 0.5 μg, 0.6 μg, 0.7 μg, 0.8 μg, 0.9 μg, 1 μg, 2 μg, 3 μg, 4 μg, 5 μg, 6 μg, 7 μg, 8 μg, 9 μg, 10 μg, 15 μg, 20 μg, 25 μg, 30 μg, 35 μg, 40 μg, 45 μg, 50 μg, 55 μg, 60 μg, 65 μg, 70 μg, 75 μg, 80 μg, 85 μg, 90 μg, 95 μg, 100 μg, 125 μg, 150 μg, 175 μg, 200 μg, 225 μg, 250 μg, 275 μg, 300 μg, 325 μg, 350 μg, 375 μg, 400 μg, 425 μg, 450 μg, 475 μg, 500 μg, 525 μg, 575 μg, 600 μg, 625 μg, 650 μg, 675 μg, 700 μg, 725 μg, 750 μg, 775 μg, 800 μg, 825 μg, 850 μg, 875 μg, 900 μg, 925 μg, 950 μg, 975 μg, 1000 μg, 1.25 g, 1.5 g, 1.75 g, 2.0 g, 2.25 g, 2.5 g, 2.75 g, 3.0 g, 3.25 g, 3.5 g, 3.5 g, 3.75 g, 4.0 g, 4.25 g, 4.5 g, 4.75 g, 5.0 g, 5.25 g, 5.5 g, 5.75 g, 6.0 g, 6.25 g, 6.5 g, 6.75 g, 7.0 g, 7.25 g, 7.5 g, 7.75 g, 8.0 g, 8.25 g, 8.5 g, 8.75 g, 9.0 g, 8.25 g, 9.5 g, 9.75g, 10 g, 20 g, 30 g, 40 g, 50 g, 60 g, 70 g, 80 g, 90 g, 100 g, or more, or any range or amount in between any two of the preceding values. The exemplary therapeutically effective amounts listed above, can, in some embodiments be administered in the methods described elsewhere herein on an hourly basis, e.g., every one, two, three, four, five, six, seven, eight, nine, ten, eleven, twelve, thirteen, fourteen, fifteen, sixteen, seventeen, eighteen, nineteen, twenty, twenty-one, twenty-two, twenty-three hours, or any interval in between, or on a daily basis, every two days, every three days, every four days, every five days, every six days, every week, every eight days, every nine days, every ten days, every two weeks, every month, or more or less frequently, as needed to achieve the desired therapeutic effect. [0049] In some embodiments, the compositions disclosed herein, e.g., compositions that comprise a chromium complex, can be administered to a subject 1 time, 2 times, 3 times, 4 times 5 times, 6 times, 7 times, 8 times, 9 times, 10 times, or more, per day, for a period of time, such as 1 day, 2 days, 3 days, 4 days, 5 days, 6 days, 7 days, 8 days, 9 days, 10 days, 11 days, 12 days, 13 days, 2 weeks, 3 weeks, 4 weeks, 5 weeks, 6 weeks, 7 weeks, 2 months, 3 months, 4 months, 5 months, 6 months, 7 months, 8 months, 9 months, 10 months, 11 months, 1 year, or more, or any amount of time in between the preceding values. [0050] In some embodiments, the compositions described herein, for example compositions that comprise chromium complexes can be administered to a subject per se, or in pharmaceutical compositions where they are mixed with other active ingredients, as in combination therapy, or suitable carriers or excipient(s). Techniques for formulation and administration of the compounds of the instant application may be found in “Remington's Pharmaceutical Sciences,” Mack Publishing Co., Easton, Pa., 18th edition, 1990. [0051] By way of example, some embodiments are formulated for topical ophthalmic administration. Some embodiments comprise a sterile solution, a preservative, a solubility enhancer, a viscosity building agent, a surfactant, a pH adjusting agent, a tonicity agent, an antioxidant, or combinations thereof. [0052] Some embodiments comprise a solution for topical ophthalmic administration having a pH from about 3.0 to about 9.0. Some embodiments comprise a solution having a pH from about 4.0 to about 8.0. Some embodiments comprise a solution having a pH from about 4.5 to about 8.0. Some embodiments comprise a solution having a pH from about 5.0 to about 8.0. Some embodiments comprise a solution having a pH from about 5.5 to about 8.0. Some embodiments comprise a solution having a pH from about 6.0 to about 8.0. Some embodiments comprise a solution having a pH from about 6.5 to about 8.0. Some embodiments comprise a solution having a pH from about 7.0 to about 8.0. Some embodiments comprise a solution having a pH from about 7.5 to about 8.0. Some embodiments comprise a solution having a pH from about 6.5 to about 7.5. [0053] Some embodiments comprise a solution for topical ophthalmic administration having an osmolarity of about 150 milliosmoles per kilogram of water (mOsm/kg) to about 450 mOsm/kg. Some embodiments comprise a solution for topical ophthalmic administration having an osmolarity of about 200 mOsm/kg to about 450 mOsm/kg. Some embodiments comprise a solution for topical ophthalmic administration having an osmolarity of about 225 mOsm/kg to about 400 mOsm/kg. Some embodiments comprise a solution for topical ophthalmic administration having an osmolarity of about 250 mOsm/kg to about 375 mOsm/kg. Some embodiments comprise a solution for topical ophthalmic administration having an osmolarity of about 275 mOsm/kg to about 350 mOsm/kg. Some embodiments comprise a solution for topical ophthalmic administration having an osmolarity of about 300 mOsm/kg to about 325 mOsm/kg. [0054] Some embodiments described herein relates to a composition, that can include an effective amount of one or chromium complexes described herein (e.g., CrHis), and a carrier, diluent, excipient or combination thereof. [0055] As used herein, a “carrier” refers to a compound that facilitates the incorporation of a compound into cells or tissues. For example, without limitation, dimethyl sulfoxide (DMSO) is a commonly utilized carrier that facilitates the uptake of many organic compounds into cells or tissues of a subject. [0056] As used herein, a “diluent” refers to an ingredient in a composition that lacks biological activity but may be otherwise necessary or desirable. For example and without limitation, it may also be a liquid for the dissolution of a compound to be administered to the eye, and/or by injection, ingestion, or inhalation. A common form of diluent in the art is a buffered aqueous solution such as, without limitation, phosphate buffered saline that mimics the composition of human blood or tears. [0057] As used herein, an “excipient” refers to an inert substance that is added to a composition to provide, without limitation, bulk, consistency, stability, binding ability, lubrication, disintegrating ability etc., to the composition. A “diluent” is a type of excipient. [0058] The compositions described herein can be administered to a human per se, or in compositions where they are mixed with other active ingredients, or carriers, diluents, excipients or combinations thereof. Proper formulation is dependent upon the route of administration chosen. Techniques for formulation and administration of the compounds described herein are known to those skilled in the art. [0059] The compositions disclosed herein may be manufactured in a manner that is itself known, e.g., by means of conventional mixing, dissolving, granulating, dragee-making, levigating, emulsifying, encapsulating, entrapping or tableting processes. Additionally, the active ingredients are contained in an amount effective to achieve its intended purpose. Many of the compounds used in the combinations disclosed herein may be provided as salts with pharmaceutically compatible counterions. [0060] One may also administer the compound in a local rather than systemic manner, for example, via administering the solution as an eye drop. In some embodiments, the eye drops consist essential of chromium histidinate complexes. [0061] The compositions may, if desired, be presented in a pack or dispenser device which may contain one or more unit dosage forms containing the active ingredient. The pack may for example comprise metal or plastic foil, such as a blister pack, or in single-use eye drop containers. The pack or dispenser device may be accompanied by instructions for administration. Compositions that can include a compound described herein formulated in a compatible carrier may also be prepared, placed in an appropriate container, and labeled for treatment of an indicated condition. [0062] Advantageously, an individual is administered a pharmaceutically effective dose of a chromium complex such as chromium histidinate alone or in combination with at least one other chromium complex. In one embodiment, a composition disclosed herein (e.g., chromium histidinate) and another chromium complex are administered substantially simultaneously. In an alternative embodiment, the compositions disclosed herein (e.g., chromium histidinate) and another chromium complex are provided to the subject sequentially in either order. If administered separately, the chromium complex and diet and composition disclosed herein (e.g., chromium histidinate) should be given in a temporally proximate manner, e.g., within a twenty-four hour period. More particularly, the chromium complex and composition disclosed herein (e.g., chromium histidinate) can be given within one hour of each other. EXAMPLES [0063] These examples are provided for illustrative purposes only and not to limit the scope of the claims provided herein. General Procedures [0064] Diabetes was induced with streptozotocin [(STZ), 55 mg/kg] by intraperitoneal injection in male Long-Evans rats. Three weeks after STZ injection, rats were divided into four groups, namely, untreated normal controls, normal rats receiving CrHis (110 μg/kg/day); untreated diabetics and diabetics treated with CrHis (110 μg/kg/day) orally for 12 weeks. [0065] In the untreated diabetic group, levels of serum glucose, glycosylated haemoglobin (HbAlc), total cholesterol (TC) and retina malondialdehyde (MDA) were significantly increased, while expressions of retina insulin, and glucose transporter 1 (GLUT 1) and glucose transporter 3 (GLUT3) and level of serum insulin were decreased. [0066] Twenty eight Long Evans rats per experiment, aged 8 weeks with 250±20 g of body weight were used in these experiments. All the animals were kept and maintained under standard guidelines. The animals were kept and maintained at 22±2° C., humidity of 55%±5% and 12/12-hour light/dark cycle. The rats were weighed every week and at the end of the study. Blood sample was collected from the tail vein of each rat for the measurement of biochemical efficacy and safety markers. [0067] The CrHis was given in the water and administered at a concentration of 110 μg/kg bw/d) to get 9.16 μg elemental Cr (kg body/d), which is an equivalent dose of 614 μg Cr for a 70-kg adult human based on previous work. The Cr concentration of the water provided the control group was negligible (<1 μg/L). The water provided the Cr-supplemented group was initially prepared as a solution containing 3000 μg CrHis/L of water. The CrPic-supplemented water was diluted to achieve the target Cr intake per group on the basis of measured water intake. To induce experimental diabetes, STZ was dissolved in citrate buffer (pH 4.5) and injected once intraperitoneally at a dose of 55 mg/kg to the remainder of the animals. A control group was given citrate buffer via intraperitoneal injection. [0068] Fourteen rats were treated with STZ (55 mg/kg body weight) through intraperitoneal injection. All rats were then fasted for 16 hour prior to treatment, but they had access to drinking water. The animals were divided into 4 groups: group I (Control) rats received citrate buffer intraperitoneally and isotonic saline, orally; group II (Control+CrHis) rats were administered chromium histidinate orally (110 μg/kg body weight) daily for a period of four weeks; group III (Diabetic) rats received single injection of STZ (55 mg/kg body weight) intraperitoneally and were also given isotonic saline, orally for the duration of the study; group IV (Diabetic+CrHis) diabetic rats were administered chromium orally as chromium histidinate (110 μg/kg body weight) daily for a period of 12 weeks after the induction of diabetes. [0069] Body weight and blood glucose concentrations were monitored weekly. Blood was collected from the tail vein of the rats. Blood glucose was determined by one touch glucometer (ACCU-Check Active, Roche Diagnostics, Mannheim, Germany) after the injection for 72 h. Before STZ injection, glucose concentrations of study rats and controls were measured and compared. After the injection of STZ, animals that exhibited fasting glucose levels greater than 140 mg/dL were considered as neonatal STZ diabetic resembling diabetes mellitus in humans. [0070] Blood samples were centrifuged at 3000×g for 10 min and sera were separated. Serum glucose concentrations were measured by using ACCU-Chek Active (Roche Diagnostics, Basel, Switzerland). Serum insulin levels were measured with the Rat Insulin Kit (Linco Research, St Charles, Mo.) by enzyme-linked immunosorbent assay (ELISA, Elx-800, BioTek Instruments, Winooski, Vt.). Serum concentrations of total cholesterol (TC) were measured by diagnostic kits (Sigma Diagnostics, St Louis, Mo.). Blood glycosylated haemoglobin (HbAlc) was also measured by routine kit (Alfabiotech, Milano, Italy) using the autoanalyzer. [0071] After rats were sacrificed, both eyes were either (1) enucleated and frozen at −80° C. for the measurements of the target biomarker(s) and/or other analysis or (2) are examined immediately post-sacrifice for morphological changes. For Western blot analyses protein extraction was performed by homogenizing the retina in 1 ml ice-cold hypotonic buffer A, containing 10 mM 2-[4-(2-Hydroxyethyl)-1-piperazinyl]ethanesulfonic acid [HEPES] (pH 7.8), 10 mM KCl, 2 mM MgCl2, 1 mM DTT, 0.1 mM EDTA, and 0.1 mM phenylmethylsulfonyl-fluoride (PMSF). The homogenates were added with 80 μl of 10% Nonidet P-40 (NP-40) solution and then centrifuged at 14,000×g for 2 min. The precipitates were washed once with 500 μl of buffer A plus 40 μl of 10% NP-40, centrifuged, re-suspended in 200 μl of buffer C [50 mM HEPES [pH 7.8], 50 mM KCl, 300 mM NaCl, 0.1 mM EDTA, 1 mM dihiothreitol [DTT], 0.1 mM PMSF, 20% glycerol], and recentrifugedat 14,800×g for 5 min. The supernatants were collected for determinations of GLUT-1, GLUT-3 and insulin according to the method described by Sahin et al. [0072] Equal amounts of protein (50 μg) were electrophoresed and subsequently transferred onto a nitrocellulosemembrane (Schleicher and Schuell Inc., Keene, N.H., USA). Antibodies against target biomarker(s) were diluted as necessary in the same buffer containing 0.05% Tween-20. Protein loading was controlled sing a monoclonal mouse antibody against β-actin (A5316; Sigma). Bands were analyzed densitometrically using an image analysis system (Image J; National Institute of Health, Bethesda, USA). [0073] After the eye extirpation, tissue (retina) of each rat was also examined grossly. The tissue was removed for histologic study, washed with normal saline, and immersion-fixed in 10% buffered formalin immediately upon removal. They were gradually dehydrated, embedded in paraffin, cut into 5-μm sections, and stained with hematoxylin and eosin for histologic examination according to standard procedures. [0074] Data were analyzed statistically using one-way ANOVA. In the analyses for the biomarker(s), the repeated statement was added in the general linear model. The group differences were attained by the Fisher's multiple comparison test [Statistical Package for the Social Sciences (SPSS)]. A P value of less than 0.05 was considered significant. Example 1 Chromium Histidinate Reduces Levels of Biomarkers Related to Diabetic Retinopathy in Rats [0075] General procedures were conducted as described above. After rats were sacrificed, both eyes were enucleated and frozen at −80° C. for the measurements of MDA, GLUT 1, GLUT3 and insulin. The retina MDA content was measured by high performance liquid chromatography (HPLC, Shimadzu, Tokyo, Japan) using a Shimadzu UV-vis SPD-10 AVP detector and a CTO-10 AS VP column in a mobile phase consisting of 30 mM KH 2 PO 4 and methanol (82.5+17.5, v/v; pH 3.6) at a flow rate of 1.2 ml/min. Column effluents were monitored at 250 nm and the volume was 20 μl. The retina homogenate (10%, w/v) was prepared in 10 mM phosphate buffer (pH 7.4), centrifuged at 13,000×g for 10 min at 4° C., and the supernatant was collected and stored at −80° C. for MDA analysis. [0076] STZ administration affected the levels of typical blood parameters characteristic for diabetes, which are also accepted values in diabetes diagnostic (glucose, insulin and HbAlc). Blood glucose, HbAlc and total cholesterol levels were significantly increased in untreated diabetic rats compared to control groups while insulin levels were decreased (P<0.5). When diabetic retinopathy rats were treated with CrHis, significant increases in blood glucose, HbAlc, insulin and total cholesterol levels were observed in diabetic retinopathy rats. CrHis treatment also resulted in a significant decrease in mean serum total cholesterol concentration of diabetic retinopathy animals. Body weight was significantly decreased (P<0.001) in the untreated diabetic rats when compared to control group. CrHis treatment significantly increased body weight (P<0.001) compared to the untreated diabetic group (Table 1). [0000] TABLE 1 Effect of CrHis supplementation on biochemical parameters in diabetic rats Parameters Control CrHis STZ STZ + CrHis Body weight (g) 330 (3.6)bc 340 (3.9)b 225 (3.5)c 250 (3.5)a Glucose (mg/dL) 110 (2.3)a 100 (2.0)a 480 (8.0)b 290 (2.7)c Insulin (μU/mL) 47.4 (0.20)a 50.3 (0.22)a 20.2 (0.25)b 25.0 (0.25)c Total cholesterol (mg/dL) 90 (0.64)a 80 (0.34)a 240 (0.90)b 218 (0.80)c Glycosylated hemoglobin 0.29 (0.02)a 0.20 (0.01)a 0.82 (0.05)b 0.45 (0.03)c (mg/g) [0077] Expressions of GLUT1, GLUT3 and insulin showed significant upward regulation (P<0.05) in the retina of diabetic rats compared to control. Treatment using CrHis significantly (P<0.05) reversed these changes to near control levels ( FIG. 1 , Panel A-C). [0078] Data are means of quadruplets of assays and expressed as relative to control (%). Blots were repeated at least 3 times (n=3) and a representative blot for each is shown. Actin was included to ensure equal protein loading. Values are LS means±SE. Different letters within the retina parts indicate statistical differences among groups (p<0.05). [0079] The retina of untreated diabetic rats had considerably higher MDA expressions compared with controls (P<0.001). A statistically significant reduction of MDA expression was found in retina of diabetic rats when the diabetic rats were treated with CrHis ( FIG. 1 , Panel D). Example 2 Chromium Histidinate Ameliorates the Physiological Effects of Diabetic Retinopathy Better than Other Chromium Species [0080] General procedures were conducted as described above. Retinas were highly organized in the normal (control) rats, with intact layers. The retinas were disorganized in the diabetic rats with impaired layers. But the retinas in CrHis group were surprisingly improved compared to the diabetes group. Similar experiments are conducted with other chromium species such as chromium nicotinate and chromium picolinate. Surprisingly, the chromium histidinate complex is more efficacious at reducing the physiological effects of diabetic retinopathy than other chromium complexes at equivalent total dosages of chromium. Example 3 Chromium Histidinate Reduces Retinal Lipid Oxidation [0081] General procedures are conducted as described above. Retinal lipids are extracted from the retinal cellular lysate and characterized by liquid chromatography-mass spectrometry. Surprisingly, the chromium histidinate complex is more efficacious at reducing the retinal lipid oxidation than other chromium complexes at equivalent total dosages of chromium. Example 4 Chromium Histidinate Reduces Free Radical Oxidation of Retinal Photoreceptors [0082] General procedures are conducted as described above. Retinal lipids are extracted from the retinal cellular lysate and characterized by liquid chromatography-mass spectrometry. Surprisingly, the chromium histidinate complex is more efficacious at reducing the free radical oxidation of retinal photoreceptors than other chromium complexes at equivalent total dosages of chromium. Example 5 Chromium Histidinate Reduces Both Hemoglobin Glycation and Retinal Protein Glycation [0083] General procedures are conducted as described above. General procedures are conducted as described above. Retinal proteins are extracted from the retinal cellular lysate and characterized by liquid chromatography-mass spectrometry and/or Western Blotting. Surprisingly, the chromium histidinate complex is more efficacious at reducing hemoglobin glycation and/or retinal protein glycation than other chromium complexes at equivalent total dosages of chromium. Example 6 Chromium Histidinate Decreases Loss of Retinal Lipoprotein Membrane Content [0084] General procedures are conducted as described above. Retinal lipids are extracted from the retinal cellular lysate and characterized by liquid chromatography-mass spectrometry. Surprisingly, the chromium histidinate complex is more efficacious at decreasing the loss of retinal lipoprotein membrane content than other chromium complexes at equivalent total dosages of chromium. Example 7 Chromium Histidinate Prevents Retinal Capillary Basement Membrane from Thickening [0085] General procedures are conducted as described above. Retinal capillary basement membrane thickening is characterized by physical examination of the eye using standard techniques. Surprisingly, the chromium histidinate complex is more efficacious at preventing retinal capillary basement membrane from thickening than other chromium complexes at equivalent total dosages of chromium. Example 8 Chromium Histidinate Decreases Microangiopathy [0086] General procedures are conducted as described above. Retinal microangiopathy is characterized using standard ophthalomogic techniques. Surprisingly, the chromium histidinate complex is more efficacious at decreasing microangiopathy than other chromium complexes at equivalent total dosages of chromium. Example 9 Chromium Histidinate Reduces Retinal Hard Exudates [0087] General procedures are conducted as described above. Retinal hard exudates are extracted from the retinal cellular lysate and characterized by liquid chromatography-mass spectrometry. Surprisingly, the chromium histidinate complex is more efficacious at reducing hard exudates than other chromium complexes at equivalent total dosages of chromium. Example 10 Co-administration of Chromium Histidinate with Insulin or Metformin Provides a Synergistic Effect in Treating Diabetic Retinopathy [0088] General procedures are conducted as described above. Co-administration of chromium histidinate with insulin or metformin is performed. Retinal biomarker(s) are extracted from the retinal cellular lysate and characterized by liquid chromatography-mass spectrometry. Surprisingly, the results demonstrate that co-administration of chromium histidinate with insulin or metformin provides a synergistic effect in treating diabetic retinopathy than at equivalent total dosages of chromium and/or insulin metformin. Example 11 Ophthalmic Solution [0089] To prepare a pharmaceutical ophthalmic solution composition, 100 mg of chromium and histidine, chromium histidinate complexes, chromium trihistidinate, chromium polyhistidinate complexs, or combinations thereof, including pharmaceutically acceptable salts, hydrates, solvates, or mixtures thereof are mixed with 0.9 g of NaCl in 100 mL of purified water and filtered using a 0.2 micron filter. The resulting isotonic solution is then incorporated into ophthalmic delivery units, such as eye drop containers, which are suitable for ophthalmic administration. [0090] Each of the papers and patents discussed herein are expressly incorporated by reference in their entirety, including any drawings or figures.

The embodiments discloses herein related chromium compositions and methods of using same for the treatment and/or prevention of diabetic retinopathy. The present application is based, in part, on the surprising discovery that the administration of chromium complexes and, in particular, the administration of chromium histidinate, improves diabetic retinopathy and symptoms thereof, reduces the levels of retina malondialdehyde and glycosylated hemoglobin, and decreases oxidative stress and lipid oxidation in the eye/retina.

CROSS REFERENCE TO RELATED APPLICATION This application is a Divisional of U.S. patent application Ser. No. 14/204,524 filed Mar. 11, 2014, now U.S. Pat. No. 9,295,246, which claims the benefit of priority to U.S. Provisional Application Ser. No. 61/777,766 filed Mar. 12, 2013. The entire disclosure of each of the applications listed in this paragraph are incorporated herein by specific reference thereto. GOVERNMENT LICENSE RIGHTS This invention was made with Government support under Dept. of Agriculture—Agricultural Research Service Agreement No.: 58-0208-3-001 (Durable Coating-Embedded Adulticide (CEA), Larvicide (CEL) and Durable Dual-Action Lethal Ovitraps (DDALO) for Management of Dengue Vector Aedes albopictus and Other Container-Breeding Mosquitoes). The government has certain rights in this invention. FIELD OF INVENTION This invention relates to killing mosquitoes, and in particular to lethal containers, apparatus, devices, systems, coatings, compositions, formulas, applications and methods of using pesticide coatings to kill adult mosquitoes and their larvae, and in particular to containers coated internally with coating-embedded pesticides designed to hold water, to attract mosquitoes, and kill adult mosquitoes and their larvae, which include specific shaped containers, and applications of using the coating-embedded larvicide to various objects such as tokens, marbles, pebbles, stones, chips and the interior of various water-holding containers, such as flower pots, water-holding dishes used under plant pots, vases, bird baths, fountains, and other similar containers, and the like. BACKGROUND AND PRIOR ART Over the years, ovitrap type containers have been used and deployed to control mosquitoes. See for example, U.S. Pat. No. 5,983,557 to Perich et al.; U.S. Pat. No. 6,185,861 to Perich; and U.S. Pat. No. 6,389,740 to Perich et al.; and Zeichner, Brian C. “The lethal ovitrap: a response to the resurgence of dengue and chikungunya”, U.S. Army Medical Journal, July-September 2011. These types of ovitraps have generally used a paper strip having insecticide that hangs within a cup filled with water up to a series of drain holes. The insecticide strip will hang into the water, with the intention of killing female mosquitoes as they land on the ovitrap to lay eggs. However, these types of Ovitraps have limitations due to the insecticide on the paper breaking down rapidly because of water contact, and also the trap is not designed to kill larvae. For example, these traps have lacked the use of a timed release of insecticide, and the water ended up breaking down the insecticide to become ineffective or not killing fast enough to prevent egg laying because of insecticide resistance in the mosquito population. A study in Key West, Fla. that used thousands of ovitraps ended up producing mosquitoes from these water filled containers. Additionally, the ovitraps only used an adulticide, which was not effective in killing mosquito larvae. Still furthermore, Mosquito ovitraps available in the market do not contain larvicide and only adulticide so if eggs are laid larvae can develop. The addition of larvicide would prevent that problem. Thus, the need exists for solutions to the above problems with the prior art. SUMMARY OF THE INVENTION A primary objective of the present invention is to provide dual action lethal containers, apparatus, devices, systems, applications and methods, which are used to kill adult mosquitoes and their larvae. A secondary objective of the present invention is to provide novel, long-lasting coatings, compositions and formulas that can be used to kill both adult mosquitoes and their larvae. A third objective of the present invention is to provide mosquito control devices and methods of using and coating water-holding containers, such as but not limited to flower pots, water holding dishes used under plant pots, vases, bird baths, and fountains coated internally with coating containing a mosquito larvicide. A fourth objective of the present invention is to provide mosquito control devices and methods of coating pebbles, stones, marbles and other types of objects coated with coating-embedded larvicide which can be added to water-holding containers. A fifth objective of the present invention is to provide mosquito control devices and methods of imbedding objects with durable coatings which releases the larvicide over time so that its action can be prolonged over the duration of a fully season. Long lasting insecticidal coatings used in the invention can prevent quick degradation of insecticidal activity as occurs when insecticides are applied directly to surfaces of lethal ovitraps. Use of slow release coatings encapsulates most insecticide so that pesticide exposure by humans is minimized when treated surfaces are accidentally contacted. Use of different active ingredients for elimination of adults and larvae can delay development of pesticide resistance in mosquito populations and provide more efficient control of disease vectors. Containment of insecticides within an ovitrap can minimize environmental contamination, non-target exposure and chances of accidental insecticide poisoning to humans and animals. Improvements Over the Prior Art. The use of long-lasting insecticidal coating provides long-lasting control, as opposed to direct application of insecticides to internal surfaces of lethal ovitraps. The invention has the addition of larvicide to lethal ovitraps. A synergist can be added to the long-lasting coating to overcome insecticide resistance in mosquito populations. The coating not only can protect the insecticidal active ingredient, but also synergists from degradation over time. Additionally, a combination of both an adulticide and a larvicide with a different mode of action in a single coating could allow for easier manufacturing. Marketing Novelty. The dual action ovitrap can be sold both in the retail market, for use by homeowners who need to eliminate mosquitoes from their property, and professional market, for use by mosquito control districts, pest control operators, the armed forces, humanitarian institutions and others involved in the control of mosquitoes in different situations. The long-lasting insecticide coatings can be marketed for other uses where insect control is desired. Such coating could be used in external building walls, internal walls, and any other surfaces where mosquitoes and other pestiferous insects may rest and congregate. The insecticidal coatings can have colors incorporated that are attractive to mosquitoes. This dual action lethal ovitrap would be useful for control of mosquitoes that vector dengue, west Nile virus, yellow fever, and other pathogens. Embedding the insecticides in coatings within lethal ovitrap can protect the active ingredient and/or synergist from degradation by the water in the ovitrap, and results in slow release of the active ingredient over time to kill mosquitoes. If the mosquitoes lay eggs before they die, a larvicide also embedded in the coating, is protected from degradation, and slowly releases over time to kill any larvae that hatch from the mosquito eggs. The dual action of the ovitrap assures that the device will not produce mosquitoes as a result of degradation of the active ingredients. Further objects and advantages of this invention will be apparent from the following detailed description of the presently preferred embodiments, which are illustrated schematically in the accompanying drawings. BRIEF DESCRIPTION OF THE FIGURES FIG. 1 is a perspective left front side of a first embodiment dual action ovitrap container. FIG. 2 is a front view of the dual action ovitrap container of FIG. 1 . FIG. 3 is a top view of the dual action ovitrap container of FIG. 1 . FIG. 4 is a side cross-sectional view of the dual action ovitrap container of FIG. 2 along arrow 4 X. FIG. 5A is a right side view of another dual action ovitrap container. FIG. 5B is a cross-sectional view of the container of FIG. 5A along arrow 5 B. FIG. 6 is a front view of the dual action ovitrap container of FIG. 5 along arrow 6 X. FIG. 7 is a left side view of the dual action ovitrap container of FIG. 5 . FIG. 8 is a top view of the dual action ovitrap container of FIG. 5 along arrow 8 X. FIG. 9 shows another embodiment of using the novel coatings with a flower pot. FIG. 10 shows another embodiment of using the novel coatings with water-holding dishes used under a plant pot. FIG. 11 shows another embodiment of using the novel coatings with a water-holding vase. FIG. 12 shows another embodiment of using the novel coatings with a water-holding bird bath. FIG. 13 shows another embodiment of using the novel coatings with a water-holding fountain. FIG. 14 shows another embodiment of using the novel coatings with small objects in a water-holding storm-water inlet. FIG. 15 shows another embodiment of using the novel coatings with small objects that can be used with another water-holding area. FIG. 16 shows another embodiment of using the novel coatings on wood surfaces, such as stalls and fences and walls. FIG. 17 is a graph of mosquito larval mortality after 0-week aging with the average live mosquitoes on the vertical axis versus exposure time on the horizontal axis. FIG. 18 is a graph of mosquito larval mortality after 20-week aging with the average live mosquitoes on the vertical axis versus exposure time on the horizontal axis. FIG. 19 is a graph of percent of mosquito eggs on the vertical axis versus cavity size on the horizontal axis. FIG. 20 shows a bar graph of results of a two-way choice test for mosquito females placed in a small-cage with containers with CEA (0.7% permethrin) vs. control, both using unchlorinated water, with number of dead mosquitoes and percentage of eggs found in each treatment on the vertical axis. FIG. 21 shows a bar graph of results of a two-way choice test for mosquito females placed in a small-cage with containers with CEA (0.7% permethrin) vs. control, both with oak-leaf infusion water, with number of dead mosquitoes and percentage of eggs found in each treatment on the vertical axis. FIG. 22 shows a bar graph of a two-way ovitrap choice test with Aedes albopictus , with percentage of mosquitoes on the vertical axis versus the location where they were found. FIG. 23 shows percent adult mosquito emergence on the vertical axis versus coatings in which the larvicide pyriproxyfen was embedded at different rates. FIG. 24 shows percent adult mosquito emergence on the vertical axis versus two coatings in which the larvicide pyriproxyfen was embedded and applied to containers which were washed with different volumes of water. DESCRIPTION OF THE PREFERRED EMBODIMENTS Before explaining the disclosed embodiments of the present invention in detail it is to be understood that the invention is not limited in its applications to the details of the particular arrangements shown since the invention is capable of other embodiments. Also, the terminology used herein is for the purpose of description and not of limitation. A list of the components will now be described. 100 First embodiment container 110 narrow cap top on container 112 grate with openings 120 raised ribs 121 internal concave ribs 122 upper end of container 126 lower curved side edges 128 bottom of container 130 hook 140 sideway protruding raised opening 200 First embodiment container 210 narrow cap top on container 212 grate with openings 220 raised ribs 221 inner rib surfaces 222 upper end of container 226 lower curved side edges 228 bottom of container 230 hook 240 sideway protruding raised opening 300 flower pot 310 internal surface of pot 400 plant pot with water dish 420 dish 425 internal surface of dish 430 pot 500 vase 510 internal surface of vase 600 bird bath 610 internal surface of bowl 700 fountain 710 internal surface of fountain 800 coated objects for a storm water inlet 810 interior surface of storm water inlet 900 coated objects for another water holding container 910 interior surface of another container 1000 small mosquito control coated objects 1100 wood stalls and fences and walls and boxes FIG. 1 is a perspective left front side of a first embodiment dual action ovitrap container 100 . FIG. 2 is a front view of the dual action ovitrap container 100 of FIG. 1 . FIG. 3 is a top view of the dual action ovitrap container 100 of FIG. 1 . FIG. 4 is a side cross-sectional view of the dual action ovitrap container 100 of FIG. 2 along arrow 4 X. Referring to FIGS. 1-4 , container 100 can have a modified pyramid shape with rounded sides. Insects such as mosquitoes can enter inside the container through grate 112 , and side raised opening 140 . The container 100 can include a raised side opening 140 so that water inside the container is maintained to be no higher than the bottom of the side opening 140 . Any water inside the container 100 can run out of side opening 140 . On the top of the container 100 can be an attachable cap such as a snap-on cap 110 . Alternatively the cap 110 can be threadably attached to the upper portion of the container 100 . A grate 112 within openings therethrough can be oriented at an inclined angle and be used to obstruct objects larger than insects, such as but not limited to leaves, branches, hands, fingers and the like, from entering container 100 . The narrow opening can create dead-air, high humidity conditions that mosquitoes prefer as oviposition and resting sites. A narrow opening can also prevent excessive rain from entering and rinsing larvicide from the interior of the ovitrap. The narrow opening also can prevent dilution of the larvicide and adulticide active ingredients which can slowly escape from the coatings in order to control mosquitoes. The inclined grate 112 opening increases the attractiveness of the trap for the mosquito. A horizontal oriented grate would not be as effective an attractant opening as an inclined grate. The inclined grate 112 also more closely replicates an opening in a tree which is usually not horizontal and the tree opening which can hold water is the most attractive hatching condition for attracting mosquitoes into the container 100 . A built on hook 130 , such as a loop, can be used to hang the container 100 in an elevated position such as but not limited to hanging the container 100 from a branch, under a tree, and the like. The novel ovitrap 100 can be deployed on a surface through bottom 128 or hanging by hook 130 from a support, as opposed to single-action ovitraps that need to be placed on a completely horizontal surface. The hook 130 offers many more opportunities for placement of ovitraps in locations that are more attractive to mosquitoes and protected from animal activities, as well as in conditions that prevent disturbances by children. Raised ribs 120 on the container 100 form concave curved stacked sections 121 inside the container 100 . The stacked concave interior surfaces 121 allow for an easier landing surface for the mosquitoes to land on and hatch. The ribs 120 and interior surfaces 121 are slightly inclined so that when water evaporates and goes down, each rib section 120 and corresponding interior surface 121 have a section above and below the water level. The ribs 120 and interior surfaces 121 have the effect of limiting the wind turbulence that can enter inside of the container 100 through the side opening 140 and grate 112 . Incoming wind can cause a Venturi effect inside the container 100 . The inside stacked concave rib sections 121 can reduce the Venturi effect and any turbulence inside the container 100 . This is very important since Mosquitoes prefer to lay eggs when there is less or no wind. The bottom 128 of the container 100 can be flat to allow for the container stability to stand on its' own on a ground or raised flat surface, with lower side curved edges 126 . The inside walls of the container can be coated with a single coating having both larvicide and adulticide described in reference to the tables below. The double coating can be coated on interior walls and the floor both below and above the water line formed from side opening 140 . The container 100 can be formed from molded plastic material such as those used to form water bottles and the like, with a rougher interior surface. The plastic container 100 can be pretreated in order to make the interior surface coatings rough and not too smooth, in order to provide cavities of approximately 150 to approximately 500 μm wide. Mosquitoes prefer to deposit eggs in indentations on the surface of containers. Laboratory testing for desired cavity sizes was done at the University of Florida, Gainesville, Fla. in the summer of 2013, where the inventors modified wood surfaces (using popsicle sticks), and glued plastic mesh on top of the sticks. Six different sizes of mesh were tested, each being placed in a cup of water, which were placed in a lab cage where mosquitoes were present. The holes of the mesh became the sides of the cavities and the wood being the bottom of the cavities. The materials were left untreated, and testing and observations was completed to determine which mesh size was most desirable for the female mosquitoes to lay their eggs. Laboratory testing determined the highest results of killed mosquitoes occurred with mesh cavity having dimensions of approximately 250 μm wide. A range of approximately 150 to approximately 500 μm wide was also determined to cover desirable mesh size cavities. The term approximately can include +/−10%. The textured internal surfaces with formed cavities demonstrate that optimum resting and oviposition can be obtained by modifying the coatings accordingly. The interior walls surfaces of the containers 100 can be roughened into having textured surfaces with cavities by at least three different processes. One process can include using a plastic or material that inherently has a rough surface. The plastic can be formed from molds that form selected cavity sizes on the interior surfaces of the plastic container. Another process can include re-treating the interior surfaces of a container, such as plastic with a separate textured material coating that artificially forms a roughened surface. For example, a paintable primer, or a sprayable primer, and the like, can be used. The textured material coatings can be selected in order to create the selected cavity sizes based on applying those material coatings to the surfaces of the container. Mosquitoes can enter either by the top or the side entry into the container (which can have a partial bottle configuration. The mosquitoes have a choice of vertical and horizontal surfaces to rest, all of which are coated with insecticidal coating. Any coating and/or primer can be applied inside the container by various techniques such as but not limited to inserting a spray nozzle in the bottle and spraying aground to cover 360° internally below a selected level. A still another process can include adding additional grains such as but not limited to sand, acrylics, into the insecticide coating, which can then be coated to the interior surfaces of the container which forms a roughened surface, having the selected cavity sizes. Similarly, techniques to spray inside the container can include but are not limited to having any coating and/or primer can be applied by inserting a spray nozzle into the opening(s) of the container and spraying around to cover 360° internally below a selected level. The outside of the container 100 can have different colors. The exterior of container can be darkened to black, brown, and other dark colors that replicate a tree type structure. For example, a dark color attracts mosquitoes. The cap 110 can have a different color such as red that causes contrast with the dark color of the rest of the container 100 , which would replicate surfaces of the tree having wet and dry areas. Mosquitoes associate red and black to ideal tree surface locations. The side opening 140 and the grate opening also appear to replicate a tree surface along with the coloring of the container surface, which are attractive to mosquitoes. The inside of the container 100 can include a separate mosquito attractant either or both embedded into the coating or loose inside the container 100 . The attractant can include but it not limited to broken leaves, artificial and natural scents, contained or not in cloth, paper, or mesh bag similar to a teabag that can replicate moist wet areas that are normally attracted to mosquitoes. The object of the interior surface of the container with or without the attractant is to form an attractant environment and not a repellent environment for mosquitoes. Table 1 lists examples of adulticide and larvacidal coating ingredients that can be used in the interior coatings of the container 100 along with a range for each components and preferred percentage for combined adultacidal and larvacidal coating. TABLE 1 Preferred Main Choice Preferred Exemplary Ingredients Ingredients Range Amount Choice of Coating 83.0-99.9989%    98.59%  Acrylic paint Oil based paint Plastic polymer Choice of Adulticidal Active 0.001-5.0%  0.7% Ingredient: Pyrethroid insecticide Organophosphate insecticide Carbamate insecticide Permethrin   0.2-5.0% 0.7% (pyrethroid) Cypermethrin  0.02-5.0% 0.1% (pyrethroid) Deltamethrin  0.001-5% 0.06%  (pyrethroid) Bifenthrin  0.001-5% 0.06%  (pyrethroid) Chlorpyrifos   0.2-5.0% 0.5% (organophosphate) Propoxur   0.2-5.0% 0.5% (carbamate) Diazinon   0.2-5.0% 1.0% (organophosphate) Choice of Larvicidal Active 0.0001-2% 0.01%  Ingredient: Bacillus 0.0001-2% 0.01%  thuringiensis israelensis Methoprene 0.0001-2% 0.01%  Pyroproxifen 0.0001-2% 0.01%  Spinosad 0.0001-2% 0.01%  Choice of Synergist:  0-10.0% 0.7% Piperonyl Butoxide  0-10.0% 0.7% MGK-264  0-10.0% 1.4% Etofenprox   0-5.0% 0.7% Pyrethrins   0-5.0% 0.7% Table 2 lists the main components along with a range for each components and preferred percentage for an adultacidal coating. TABLE 2 Preferred Main Choice Preferred Exemplary Ingredients Ingredients Range Amount Choice of Coating 85.0-98.999%   98.6%  Acrylic paint Oil based paint Plastic polymer Choice of Adulticidal Active 0.001-5.0%  0.7% Ingredient: Pyrethroid insecticide Organophosphate insecticide Carbamate insecticide Permethrin (pyrethroid) 0.2-5.0% 0.7% Cypermethrin 0.02-5.0%  0.1% (pyrethroid) Deltamethrin (pyrethroid) 0.001-5%  0.06%  Bifenthrin (pyrethroid) 0.001-5%  0.06%  Chlorpyrifos 0.2-5.0% 0.5% (organophosphate) Propoxur (carbamate) 0.2-5.0% 0.5% Diazinon 0.2-5.0% 1.0% (organophosphate) Choice of Synergist:  0-10.0% 0.7% Piperonyl Butoxide  0-10.0% 0.7% MGK-264  0-10.0% 1.4% Etofenprox   0-5.0% 0.7% Pyrethrins   0-5.0% 0.7% Table 3 lists the main components along with a range for each components and preferred percentage for larvacidal coating. TABLE 3 Preferred Main Choice Preferred Exemplary Ingredients Ingredients Range Amount Coating (choice of one) 88.0-99.9999%    99.82%  Acrylic paint Oil based paint Plastic polymer Choice of Larvicidal Active 0.0001-2% 0.01% Ingredients: Bacillus 0.0001-2% 0.01% thuringiensis israelensis Methoprene 0.0001-2% 0.01% Pyroproxifen 0.0001-2% 0.01% Spinosad 0.0001-2% 0.01% Choice of 1-3 Synergists:  0-10.0%  0.7% Piperonyl Butoxide  0-10.0%  0.7% MGK-264  0-10.0%  1.4% Etofenprox   0-5.0%  0.7% Pyrethrins   0-5.0%  0.7% The interior surface coatings can include those described and used in related U.S. patent application Ser. No. 13/866,656 to Koehler et al. which is assigned to the same assignee as that of the subject invention, and which is incorporated by reference in its' entirety. FIG. 5A is a right side view of another dual action ovitrap container 200 . FIG. 5B is a cross-sectional view of the container of FIG. 5A along arrow 5 B. FIG. 6 is a front view of the dual action ovitrap container 200 of FIG. 5 along arrow 6 X. FIG. 7 is a left side view of the dual action ovitrap container 200 of FIG. 5 . FIG. 8 is a top view of the dual action ovitrap container 200 of FIG. 5 along arrow 8 X. Referring to FIGS. 5A-8 , part numbers 210 , 212 , 220 , 221 , 222 , 226 , 228 , 230 , 240 correspond and function to similar part numbers 110 , 112 , 120 , 121 , 122 , 126 , 128 , 130 and 140 in the previous embodiment. In these figures, the bottom of the container 200 can have a length between the back and front of approximately 5 inches and a width between the left side and right side of approximately 4¾ inches, and a height between the bottom 228 and the upper end of the container 200 being approximately 4½ inches from the bottom 228 of the container 200 , with the upper end having a length of approximately 2⅛ inches and a width of approximately 2¾ inches. The parallel raised ribs 220 can be spaced apart from each other by approximately ½ inch and each rib can be approximately ½ inch thick, and can extend outward from the sides of the container 200 by approximately ⅜ of an inch. Each of the ribs 220 can be angled downward from the front of the container to the rear of the container. At the bottom 228 of the container 200 , the lowest rib can start approximately 1¼ inches from the front of the container 200 and angle downward to be approximately 1 inch from the rear of the container 200 . The ribs 220 and interior surfaces 221 have the effect of limiting the wind turbulence that can enter inside of the container 200 through the side opening 240 and grate 212 . Incoming wind can cause a Venturi effect inside the container 200 . The inside stacked concave rib sections 221 can reduce the Venturi effect and any turbulence inside the container 200 . This is very important since Mosquitoes prefer to lay eggs when there is less or no wind. The novel ovitrap internal incline plane rib surfaces offer both horizontal and vertical surfaces for female mosquitoes to oviposit and rest. This configuration makes these surfaces available to oviposition and resting regardless of the level of the water in the ovitrap. All of these surfaces can be coated with the coating-embedded larvicides and adulticides. The inclined grate 212 can have a generally oval shape with a width of approximately 2¾ inches. The sideway protruding opening 240 can be generally oval shape with a height of approximately 1⅛ inches and a width of approximately ⅞ inch. Other dimensions are shown in the figures. The coatings described above, and all their applications with the containers 100 , 200 can be used with other water holding containers, and objects. FIG. 9 shows another embodiment of using the novel coatings with a flower pot 300 . The internal surface 310 can be coated with coatings containing a mosquito larvicide coatings. FIG. 10 shows another embodiment of using the novel coatings with a water holding dishes 420 used under a plant pot 430 . The internal surface 425 of the dish 420 can be coated with coatings containing a mosquito larvicide coatings. FIG. 11 shows another embodiment of using the novel coatings with a water holding vase 500 . The internal surface 510 of the vase 500 can be coated with coatings containing a mosquito larvicide coatings. FIG. 12 shows another embodiment of using the novel coatings with a water holding bird bath 600 . The internal surface 610 of the bath bowl can be coated with coatings containing a mosquito larvicide coatings. FIG. 13 shows another embodiment of using the novel coatings with a water holding fountain 700 . The internal surface 710 of the fountain can be coated with coatings containing a mosquito larvicide coatings. Additional mosquito control objects 1000 can be coated with larvicide such as but not limited to pebbles, stones, marbles and other types of objects coated with coating-embedded larvicide. These small coated objects can be placed in water holding containers such as but not limited to using untreated containers previously described or other types of containers so that the larvicide can leach out over time. Additionally, the interior coated water holding containers can also have the small coated objects 100 dropped inside the containers. FIG. 14 shows another embodiment of using the novel coatings with a small coated objects 1000 in a water holding storm water inlet 800 . Alternatively internal surface areas 810 in the storm water inlet can also be coated with coatings containing mosquito larvicide coatings. The small coated objects can also be dropped into standing water in storm water inlets and the like so as to prevent those areas from becoming larvae breeding grounds. Also any other type of standing water can use the coated small objects dropped into the standing water. FIG. 15 shows another embodiment of using the novel coatings with a small coated objects 1000 in another water holding container 900 such as an aquarium. Alternatively, internal surface areas 910 can also be coated with coatings containing mosquito larvicide coatings. FIG. 16 shows another embodiment of using the novel coatings on wood surfaces 1100 , such as wooden stalls for horses and fences and walls and boxes, and the like. Other surfaces that can become damp and wet, such as but not limited to other wood surfaces and the like, can also be treated with the coatings. FIGS. 17-24 show the results of testing using the containers and different coatings of the first two embodiments of the invention described above for killing mosquitoes. FIG. 17 is a graph of mosquito larval mortality over 0-week aging with amount of mosquitoes on the vertical axis versus exposure time on the horizontal axis. FIG. 18 is a graph of mosquito larval mortality over 20-week aging on the vertical axis versus exposure time on the horizontal axis. FIG. 19 is a graph of percent of mosquito eggs on the vertical axis versus cavity size on the horizontal axis. FIG. 20 shows a bar graph of results of a two-way choice test for mosquito females placed in a small-cage with containers with CEA (0.7% permethrin) vs. control, both using unchlorinated water, with number of dead mosquitoes and percentage of eggs found in each treatment on the vertical axis. FIG. 21 shows a bar graph of results of a two-way choice test for mosquito females placed in a small-cage with containers with CEA (0.7% permethrin) vs. control, both with oak-leaf infusion water, with number of dead mosquitoes and percentage of eggs found in each treatment on the vertical axis. FIG. 22 shows a bar graph of a two-way ovitrap choice test with Aedes albopictus , with percentage of mosquitoes on the vertical axis versus the location where they were found. FIG. 23 shows percent adult mosquito emergence on the vertical axis versus coatings in which the larvicide pyriproxyfen was embedded at different rates. FIG. 24 shows percent adult mosquito emergence on the vertical axis versus two coatings in which the larvicide pyriproxyfen was embedded and applied to containers which were washed with different volumes of water. Referring to FIGS. 17-18 , the placement of the larvicide pyriproxyfen in a coating does not prevent its action in preventing mosquito emergence, either with new material or material that had been aged for 20 weeks. In water that is in contact with the coating-embedded larvicide, or larvicide applied directly to the container without coating, mosquito larvae start to die as they reach the pupal stage. This shows that the coating does not interfere with the larvicide action. By embedding the larvicide pyriproxyfen in a coating, the mosquito killing action is protected from degradation for more than 20 weeks. Referring to FIG. 19 , mosquitoes ( Aedes aegyptii and Aedes albopictus ) preferred to lay eggs in cavities of 250 μm size, whereas smaller and larger cavities were not as preferred, and very large cavities (2000 μm) were even less preferred. This figure shows that a certain texture to the coating or container walls can make it a preferred oviposition site. Referring to FIGS. 20-22 , female mosquitoes were placed in cages where they had a choice of 2 containers filled with water to stimulate oviposition, one container with a coating-embedded adulticide (CEA) containing the adulticide permethrin, and the other container containing no insecticide. Reference to FIG. 20 , pure water was used, whereas reference to FIG. 21 , the water was mixed with oak-leaf infusion. In both tests, higher numbers of dead mosquito females were found in the adulticide-containing water, whereas greater number of eggs were found in containers with no insecticide. The presence of leaf infusion did not prevent the insecticidal action of the coating-embedded adulticide. Referring to FIG. 22 , adult female mosquitoes were found dead mostly in the container coated with coating-embedded adulticide, whereas few mosquitoes were found dead in the water-only control or the cage floor. This shows that once the adults contact the coating-embedded adulticide, they normally do not leave the container and die. Few mosquitoes that are able to fly away from the container with the coating-embedded adulticide also die later. Referring to FIG. 23 , three different coating were used to embed the larvicide pyriproxyfen at 3 different rates. Coatings were applied to plastic containers that were filled with water, before mosquito larvae were transferred to these containers. The addition of pyriproxyfen to different coatings produced similar results (no emergence of mosquitoes even at low pyriproxyfen content) while in the water standard, mosquito emergence was only inhibited at the high pyriproxyfen level. This shows that the different coatings can protect the action of pyriproxyfen. Several different formulae (polycrylic, Polyurethane and Latex paint) have been tested as coatings for the larvicide. All coatings performed well in preventing adult emergence from larvae added to water-holding containers coated internally with the coating-embedded larvicide even with 0.0001% of the active ingredient in the coating. Water treated with 0.01% rate is considered potable by the World Health Organization (WHO). Referring to FIG. 24 , two of the coating tested previously (refer to FIG. 23 ) were also tested for durability under high volume washing to see if they could stand under heavy rains. The coatings applied to plastic containers were subject to continuous washing with tap water for total volumes equivalent to 5×, 20×, and 50× the container volumes. Afterwards the containers were refilled with fresh water and mosquito larvae were added to the water. Adult emergence from the larvae was only observed in containers with coatings that contained no embedded larvicide. The larvicide embedded in both coatings prevented the emergence of adults, even when the coating was washed with 50× volume of water. Coatings prevent larvicide washing off, with up to 50 times the volume of water as contained in the ovitrap. Most larvicides are applied to water and disappear when containers are emptied and re filled either naturally by rain action or by other means. The coating constantly treats new water put in containers with enough larvicide to preserve the mosquito-killing action. Both polycrylic and polyurethane protect the action of pyriproxyfen larvicide when containers coated with these materials are subjected to washing. This shows that coating-embedded larvicide can survive extensive rain-water rinsing. The addition of larvicide kills any larvae that can emerge from eggs that females are able to lay before dying from exposure to adulticide in the lethal ovitrap. Field deployment of single-action lethal ovitrap allowed development of larvae which can lead to actual increase in the mosquito population. While the invention has been described, disclosed, illustrated and shown in various terms of certain embodiments or modifications which it has presumed in practice, the scope of the invention is not intended to be, nor should it be deemed to be, limited thereby and such other modifications or embodiments as may be suggested by the teachings herein are particularly reserved especially as they fall within the breadth and scope of the claims here appended.

Dual action lethal containers, systems and methods and novel compositions and formulas which are used to kill mosquitoes and their larvae. Generally pyramid shaped containers can have combined interior larvacidal and adultacidal coatings above and below a side opening in the container. A removable inclined grate cap can also allow for mosquitoes to enter into the container. Inclined stacked walls inside the container form attractive surfaces for mosquitoes to breed. Water-holding containers, such as flower pots, water holding dishes used under plant pots, vases, bird baths, and fountains and storm water inlets, can be coated with novel larvicide and/or adulticide coatings. Small objects can be coated with larvicide or larvicide and adulticide combination, which can be dropped in water-holding containers which can leach out pesticide over time which prevents mosquitoes from breeding in the water-holding containers.

BACKGROUND OF THE INVENTION [0001] 1. Field of the Invention [0002] The present invention is generally related to manufacturing floor control systems and methods, and more specifically, to a method for dynamically generating work flows for components based on sensed production activities and/or order characteristics. [0003] 2. Description of the Related Art [0004] Today's customers demand that products be tailored to their specifications and be delivered in a ready-to-use manner. They also demand the lowest possible cost. These conflicting demands place great pressure on manufacturing organizations to efficiently produce solutions based on customer specifications. [0005] As product complexity increases and product life cycles become shorter, it is increasingly difficult to verify product configurations or permutations prior to shipment. Currently, three techniques are used. The first, percentage sampling, involves defining a percentage of products that must be routed through a specific inspection step or operation somewhere in the manufacturing process. For fixed products that are all identical, statistical process control (SPC) can be used to determine optimum sampling rates, etc. This process is most effective in a high-volume business that has little variation product content, single-unit based manufacturing (i.e., units of 1), and constant cycle times. [0006] The second technique, 100% inspection, involves routing each and every assembly through a specific inspection step or operation somewhere in the manufacturing process to ensure quality. The third technique, operator training, involves training on employees to recognize problems during the normal process steps and then relying on judgment to take appropriate actions. The second and third approaches are more effective in a low volume, high margin businesses. SUMMARY OF THE INVENTION [0007] The present invention provides a method for dynamically altering manufacturing routings to add, remove, or skip operations and combinations of operations within a shop floor control system, both at the present step and at future steps in the routing map or tree, considering all of the factors present when the new routing is generated. Significantly, the dynamic work flow adjustment is not limited to a pre-defined set of possibilities. That is, the manufacturing entity does not need to pre-define all possible routing maps ahead of time. Embodiments can build and modify routings in real-time, as the assembly is built. [0008] Embodiments of the present invention may also provide for dynamically controlling the interaction of more than one sampling method on any given product at any one time. That is, these embodiments blend and adjust routings based on multiple sampling strategies operative on the same assembly. In addition, embodiments of the invention may dynamically generate sampling orders for complex configured products where the configuration determines the sampling plan desired, or where past actions and analysis are taken into account to develop future sampling in future production cycles. [0009] One aspect of the present invention is a computer-implemented method for dynamically generating a manufacturing production work flow. One embodiment of this method comprises receiving indication that an assembly has completed a manufacturing operation, the assembly having a work flow and a sampling strategy associated therewith; querying a data source for characteristics of a plurality of previously sampled components; querying a manufacturing floor control system for current production status; and dynamically updating the work flow for the assembly based at least in part on the sampling strategy, characteristics of the plurality of previously sampled components, and the current production status. [0010] Another aspect of the present invention is a method for deploying computing infrastructure, comprising integrating computer readable program code into a computing system, wherein the code in combination with the computing system is adapted to perform a method for generating a manufacturing production work flow. The method for generating a manufacturing production work flow, in turn, comprises receiving indication that an assembly has completed a manufacturing operation, the assembly having a work flow and a sampling strategy associated therewith; querying a data source for characteristics of a plurality of previously sampled components; querying a manufacturing floor control system for current production status; and dynamically updating the work flow for the assembly based at least in part on the sampling strategy, characteristics of the plurality of previously sampled components, and the current production status. [0011] Another aspect of the present invention is a system, comprising a processing unit and a memory operatively connected to the processing unit. In one embodiment, the memory contains an adaptive engine configured to receive indication that an assembly has completed a manufacturing operation, the assembly having a work flow and a sampling strategy associated therewith; query a data source for characteristics of a plurality of previously sampled components; query a manufacturing floor control system for current production status; and dynamically update the work flow for the assembly based at least in part on the sampling strategy, characteristics of the plurality of previously sampled components, and the current production status. [0012] One feature and advantage of some embodiments is that they provide the ability for a manufacturing floor control system to sense changes in throughput and automatically adjust sampling to keep a smoother rate. For example, embodiments can adjust with varying manufacturing activities, such as: short parts, priority changes, critical order situations, revenue trade-offs, quality holds, etc. Some embodiments may also support combinatorial methods (i.e., multiple sampling strategies in effect at the same time) and support multiple dimensions (i.e., account for sampling activities driven from other processes, product, etc.) [0013] Another feature and advantage of some embodiments is that, unlike conventional statistical quality control techniques, coverage can be ensured for uniquely configured products and, in cases where new configurations are ordered in batches by customers, to identify which one will complete the manufacturing process first and thus should be verified to validate the entire shipment or batch. This, in turn, ensures less product escapes and customer quality issues are contained at the manufacturing location, while limiting quality inspection resources to minimum level required to maintain/ensure quality targets are being met prior to shipment. [0014] Yet another feature and advantage of some embodiments is that they allow for real-time controlled response to containing quality issues as they are detected, without requiring ‘armies’ of people finding/tracking machines on a production floor. These embodiments help ensure adequate testing is performed when product or process changes are released, especially when the first instance of a customer order to be affected by the changes is not known when released into production. [0015] Embodiments of the present invention are also desirable because they provide the ability to have sampling algorithms impact future activities. Thus, for example, one embodiment can determine that when completing operation X, you need to do a random sampling at operation X+1, but since you inserted operation X+1 after operation X, you also need to add operations Y 1 , Y 2 , and Y 3 later in manufacturing as operations X+20, X+21, and X+22. [0016] In addition, some embodiments are desirable because they can look at manufacturing impacts on an order by order basis to steer sampling to avoid production cycle time issues. Thus, for example, if a product needs certain percentage sampling on a product line, but an order is running late due to supply constraints, embodiments can pick an alternative candidate and still met the required compliance percentage. BRIEF DESCRIPTION OF THE DRAWINGS [0017] So that the manner in which the above recited features, advantages and objects of the present invention are attained and can be understood in detail, a more particular description of the invention, briefly summarized above, may be had by reference to the embodiments illustrated by the appended drawings. These drawings, however, illustrate only typical embodiments of the invention and are not limiting of its scope, for the invention may admit to other equally effective embodiments. [0018] FIG. 1A shows one embodiment of a manufacturing floor control system. [0019] FIGS. 1B-1C depict some sample tables in the WIP database. [0020] FIG. 2 is a high-level overview of one embodiment of the present invention in operation [0021] FIG. 3 is an original production routing for an example product. [0022] FIG. 4 illustrates a modified production routing for the example product, according to a “first off” sampling strategy. [0023] FIG. 5 illustrates a modified production routing for the example product, according to a ‘percentage’ sampling strategy. [0024] FIG. 6 illustrates a modified production routing for the example product, according to a ‘special config’ sampling strategy. [0025] FIG. 7 illustrates the operation of one adaptive engine embodiment. [0026] FIG. 8 illustrates one embodiment of the first instance sampling (“FOT”) sampling program in more detail. [0027] FIG. 9 illustrates one embodiment of a fingerprint ID service. [0028] FIG. 10 illustrates how to calculate a fingerprint in more detail. [0029] FIGS. 11-12 illustrate the operation of the rate/qualification based sampling strategy program in more detail. DETAILED DESCRIPTION [0030] FIG. 1A shows one embodiment of a manufacturing floor control system 100 capable of dynamically altering manufacturing work flows in real time based on multiple sampling strategies and changing product configurations on an individual unit basis. This manufacturing floor control system 100 comprises one or more central processing units 110 a - 110 d (“CPU”) connected to a main memory unit 112 by a system bus 119 . The main memory 112 contains an operating system 124 , manufacturing execution system (MES) 126 , and a work in progress database (WIP) 128 . The MES 126 , in turn, comprises an adaptive engine 121 and a fingerprint ID service 123 , and is in communication with an external first off test (FOT) sampling strategy program 122 a , an external rate/qualify (RATE) sampling strategy program 122 b , and an external special configuration sampling strategy program 122 c (collectively sampling programs 122 ). The MES 126 controls the flow of a plurality of manufacturing number (MFGN) assemblies 190 a , work units 190 b , sub-work-units 190 c , etc (for clarity, all of the various product levels will be referred to herein as assemblies 190 ) past a variety of managed stations 191 . At some of the managed stations 191 , assembly tasks are performed; at others, inspection tasks are performed. [0031] This manufacturing floor control system embodiment 100 further comprises a mass storage interface 114 , a terminal/display interface 116 , a network interface 118 , and an input/output (“I/O”) interface 120 by the system bus 119 . The mass storage interfaces 114 , in turn, connect the system bus 119 to one or more mass storage devices, such as a direct access storage device 140 or a readable/writable optical disk drive 142 . The network interfaces 118 allow the manufacturing floor control system 100 to communicate with the managed stations 191 over a communications medium 116 . [0032] As best shown in FIGS. 1B-1C , the WIP database 128 contains a sampling strategy table 180 comprising a plurality of WIP records 170 (one shown for clarity). Each WIP record 170 contains a product group field 171 , a sequence field 172 , an activation criteria field 173 , an invoking operation field 174 , a sampling exclusion criteria field 175 , a conditions field 176 , a sampling program type field 177 , a manufacturing entity level field 178 , and a WIP item field 179 . The WIP database 128 also contains a WIP history table 181 containing a plurality of WIP records 182 a - 182 c containing a running history of each WIP item 179 ; a first_config history table 184 a date on which each unique assembly 190 was first built; and a first_config requirements table 186 that defines the specific operation(s), quantity, and expiration date(s) that will be done for each type of assembly. [0033] FIG. 2 provides a high-level overview 200 of one embodiment of the present invention in operation. At block 202 , the MES 126 receives an external call from one of its managed stations 191 , triggered by the completion of a process step, and then sends the current routing/product data for that assembly 190 to the adaptive engine 121 . At block 204 , the adaptive engine 121 reviews current sampling strategies for the assembly 122 , along sampling history for that type of assembly 190 . At block 206 , the adaptive engine 121 resolves one or more sampling strategies assigned to the current assembly 190 , and then generates an updated routing. In some embodiments, this will include using one or more of the external sampling programs 122 . These programs 122 , in turn, can resolve strategies defined against the assembly 190 as a whole and/or against its sub-assemblies, sub-sub-assemblies, etc. Control returns again at block 202 , where the adaptive engine 121 will return the updated routing to the MES 126 , which generates the corresponding work orders. In this way, the multiple sampling strategies can be set in motion for each assembly, and execution of these strategies is adapted in real time to respond to actual floor conditions. [0034] FIGS. 3-6 further illustrate the adaptive engine 121 in operation. FIG. 3 shows the original production routing 300 for an example product 302 , such as a server. The product 302 comprises a plurality of a first type of assembly 304 a - 304 e , such as a drawer build; a second type of assembly 310 , such as a controller; and a third type of assembly 320 a - 320 b , such as a power supply unit. The first assemblies 304 in this example are merged into a higher assembly unit 330 ; which in turn is merged with the second assembly 310 and the third assembly 320 to form a routing group 340 a - 304 n , such as a system level build unit. The routing groups 340 , in turn, are processed through a series of system level manufacturing operations 342 a - 342 n . The routing groups 340 are eventually combined with one or more accessories 345 to form a final customer shipment 350 . [0035] FIG. 4 shows a modified production routing 400 for the example product 402 , according to the “first off” sampling strategy 122 a . As in FIG. 3 , the product 402 comprises a plurality of a first type of assembly 404 a - 404 e ; a second type of assembly 410 ; and a third type of assembly 420 a - 420 b . The first assemblies 404 in this example are merged into a higher level assembly 430 ; which in turn is merged with the second assembly 410 and the third assembly 420 to form a routing group 440 a - 440 n . The routing groups 440 , in turn, are processed through a series of system level manufacturing operations 442 a - 442 n . The routing groups 440 are eventually combined with one or more accessories 445 to form a final customer shipment 450 . Because the manufacturer has implemented the ‘first off’ sampling strategy 122 a , however, the adaptive engine 121 dynamically adds operations 460 and 462 to the assembly 430 , as this was the first time this particular “group” configuration was produced. [0036] FIG. 5 shows a modified production routing 500 for the example product 502 , according to overlapping ‘first off’ strategy 122 a and ‘rate/qualify’ sampling strategy 122 b . As in FIG. 3 , the product 502 comprises a plurality of a first type of assembly 504 a - 504 e ; a second type of assembly 510 ; and a third type of assembly 520 a - 520 b . The first assemblies 504 in this example are merged into a higher level assembly 530 ; which in turn is merged with the second assembly 510 and the third assembly 520 to form a routing group 540 a - 540 n . The routing groups 540 , in turn, are processed through a series of system level manufacturing operations 342 a - 542 n . The routing groups 540 are eventually combined with one or more accessories 545 to form a final customer shipment 550 . Because the manufacturer has implemented both the ‘first off’ 122 a and the ‘rate/qualify’ 122 b sampling strategies, operation 564 was also dynamically added to unit of work 520 b as that type of assembly hit desired sample rate. [0037] FIG. 6 shows a modified production routing 600 for the example product 602 added a ‘special config’ 122 c sampling strategy to the ‘first off’ 122 a and ‘percentage’ 122 b strategies. As in FIG. 3 , the product 602 comprises a plurality of a first type of assembly 604 a - 604 e ; a second type of assembly 610 ; and a third type of assembly 620 a - 620 b . The first assemblies 604 in this example are merged into a higher level assembly 630 ; which in turn is merged with the second assembly 610 and the third assembly 620 to form a routing group 640 a - 640 n . The routing groups 640 , in turn, are processed through a series of system level manufacturing operations 642 a - 642 n . The routing groups 640 are eventually combined with one or more accessories 645 to form a final customer shipment 650 . Because the manufacturer has also added the ‘special config’ 122 c sampling strategy, however, a system level operation 640 b was dynamically removed due to the presence of the triggering special configuration. [0038] FIG. 7 illustrates the operation of one adaptive engine embodiment 121 in more detail. At block 702 , the adaptive engine 121 receives an external call from one of the various systems 191 under its control. These calls occur each time an assembly 190 has reached a defined operation 174 in its manufacturing flow. At block 704 , the adaptive engine 121 determines if the assembly 190 has an existing ‘currently active sampling plan’ (not shown) in the work in progress (WIP) database 128 . [0039] If the adaptive engine 121 determined at block 704 that the product does not have an existing sampling plan, the adaptive engine 121 first searches the sampling strategy table 180 for matching record product groups 171 and activation criteria 173 at blocks 730 - 734 . That is, the manufacturing entity in this embodiment has defined various process steps and tests it wants to occur. The adaptive engine 121 searches the sampling strategy table 180 to determine if a matching strategy exists. If the adaptive engine 121 finds a matching strategy, the adaptive engine 121 will start a new WIP record 182 in the WIP database 128 at block 738 and update the strategies WIP table 170 at block 732 . This initiates the record in the WIP table that future processing will update. [0040] If the adaptive engine 121 determined at block 704 that an active sampling plan exists or if the adaptive engine 121 created a new active sampling plan at blocks 730 - 738 , the adaptive engine 121 then begins to apply the strategy at blocks 706 - 724 . More specifically, starting at block 706 , the adaptive engine 121 searches the WIP record 170 for operations 174 that match the triggering event (block 702 ). The adaptive engine 121 then reviews the corresponding sampling exclusion criteria 175 at blocks 708 - 712 to determine if there are any systematic reasons why the action should not occur (e.g., the test station is unavailable, the action occurs too near a critical deadline). In some embodiments, this may be as simple as reviewing the WIP database records 180 for the corresponding criteria 175 . In other embodiments, these blocks may include calling one of the sampling strategy programs 122 at block 710 to resolve more complex set of circumstances. If the action is excluded by the exclusion criteria, the adaptive engine 121 records this fact in the WIP database record 182 for the assembly 190 and then returns the next process step at block 728 in response to the original external call (block 702 ). [0041] If the action was not excluded at blocks 708 - 712 , the adaptive engine 121 then calls one or more of the sampling dimension programs 122 at blocks 714 - 718 to determine if any actions need to be added to or deleted from the manufacturing routing for this particular product. These one or more sampling programs 122 include the FOT 122 a , RATE 122 b , and special config 122 c programs described with reference to FIGS. 3-6 . [0042] If the sampling dimension programs 122 did not recommend a change to the routing (block 718 ), the sampling dimension program adds the ‘updated’ routing to the routing map at block 728 , where the update will indicate no changes were required. However, if the sampling dimension programs 122 did recommend a change to the routing (block 718 ), then the adaptive engine 121 begins to iterate through each unit under evaluation at blocks 720 - 726 . More specifically, at block 720 , the adaptive engine 121 first determines whether, for the current unit, this is a continuation of an existing sampling strategy. If so, then the sampling proceeds directly to block 723 ; otherwise, the adaptive engine 121 updates the WIP table at block 721 and then proceeds to block 724 . [0043] At block 724 , the adaptive engine 121 reviews the conditions field 176 and the recommended sampling dimensions (blocks 714 - 718 ), resolves the conditional logic, and then calculates routing change orders. These routing change orders, in turn, determine if/when various operations occur in view of past sample selection, execution, and/or results. For example, in one embodiment, the conditions field 176 may contain an “*ALL” condition or an “*OPT” condition. The “*ALL” condition indicates the corresponding operation should be executed if the sampling dimension program returns a routing change. The “*OPT” condition indicates that the corresponding operation should execute only if the calling sampling dimension returns a routing change and any of the previous conditions have not been met for the manufacturing entity. Table 1 provides the resolution of how the conditional Boolean logic resolves in some example circumstances. [0000] TABLE 1 Mfg. Sampling Entity Conditions Dimension Level Interpretation of Conditional Logic *ALL 1. FOT 1. WU 1. If the FOT program recommends a routing change, then *ALL means VALID *OPT 2. PART 2. WU 2. If the PART program recommends a routing change and FOT (1) was also VALID, then *OPT means that this operation is skipped for this mfg. entity. IF FOT (1) was INVALID and if PART recommends a routing change, then *OPT means VALID *ALL 3. FOT 3. MFGN 3. IF FOT for different ENTITY level recommends routing change, then *ALL means VALID *OPT 4. RATE 4. MFGN 4. If RATE recommends routing change and none of the previous (FOT (1), RATE (2), FOT (2)) were VALID, then *OPT means VALID. If any of (FOT (1), RATE (2), FOT (2)) were VALID, then OPT means operation is skipped. As shown, the “*OPT” condition is particularly desirable because it helps distribute the global sampling plan across the total production run. That is, the “*OPT” condition prevents one particular assembly 190 from being sampled repeatedly, thus throwing off the overall validity of the testing program. The “*OPT” condition can also help avoid bottlenecks by allowing inspection operations to be deferred during particularly busy times or in response to shortages and/or outages. [0044] FIG. 8 illustrates one embodiment of the first instance sampling (“FOT”) sampling program 122 a in more detail. In operation, each order is processed by a fingerprint service 123 that coverts the specific list of machine type model numbers (MTMs, sometimes known as product numbers or SKUs), feature codes, and quantities into a fingerprint. The resulting fingerprint is then checked against a database of previously built products and, if fingerprint not found, the order is assigned the required additional operation(s) and the table is updated. If, however, the fingerprint is found, then the system's 100 current date is compared against an ‘expiration’ criterion. If the previous instance was too old, then the current order is also scheduled for inspection. [0045] More specifically, at block 802 , the FOT sampling program 122 a receives order information from the adaptive engine 121 indicating that the organization wants “FOT” sampling and indicating that the order passed all of the exclusionary checks (described with reference to blocks 708 - 712 in FIG. 7 ). Next, the FOT program 122 a determines at blocks 804 - 810 what product level the order involves, e.g., system level analysis 806 , unit of work level analysis 808 , or order level analysis 810 . This operation may involve reviewing the first_config requirements table 186 ( FIG. 10 ). At block 820 , the FOT program 122 a then determines whether the assembly 190 already has an appropriate level fingerprint in the WIP database 128 . If not, the FOT program 122 a first if checks an ignore/suppress table 821 to determine if any portions of the configuration can be ignored when calculating the fingerprint at blocks 822 - 823 , then calls the fingerprint service 123 at block 824 to calculate the fingerprint using the required level, nomenclature, and entity number. [0046] At block 830 , the FOT program 122 a compares the fingerprint for the current assembly 190 to the first_config history table 184 ( FIG. 10 ) in the WIP database 128 . The sampling dimension program 130 then determines at block 832 if the required sampling quantity for this fingerprint has been met within the date range. Part of this operation includes querying the first_config history table 184 . If additional sampling is required, the FOT program 122 a determines which operations to add at block 836 , again using the first_config requirements table 186 . The FOT program 122 a concludes by updating the WIP records at block 838 and then returning a “sampling required” response, together with the correct operation(s), to the MES 126 at block 840 . [0047] If, however, the FOT program 122 a determined at block 832 that the required quantity of this config ID has already been met within the date range, the FOT program 122 a writes this result to the first_config history table 184 at block 850 and then returns a “sampling not required” response to the MES 126 at block 852 . [0048] FIG. 9 illustrates one embodiment of the fingerprint ID service 123 . At block 904 , the fingerprint ID service 123 receives an order (block 902 a - 902 c ) from the adaptive engine 121 requesting a new or updated fingerprint. At block 906 , the fingerprint ID service 123 parses the order to obtain the information that will be required to form the fingerprint, such as the entity ID, the units of work and their IDs, the unit placement, the device codes, feature bills of materials (BOM) and placement, and installed parts and placement. At blocks 908 - 914 , the fingerprint ID service 123 parses the order to determine what type of fingerprint is responsive to the original request. [0049] The fingerprint ID service then gathers the information necessary to calculate the fingerprint at block 916 . In some embodiments, this may include querying an ignore-suppress table at blocks 918 - 920 to determine if any portions of the order should be ignored for this assembly. That is, if a ‘system’ fingerprint normally is normally generated from items A, B, C, and D, the ignore-suppress table may indicate that the fingerprint ID service should skip item B for this particular assembly 190 . The fingerprint ID service 123 then calculates the requested fingerprint type at block 922 and returns the result at block 924 . [0050] FIG. 10 illustrates how to calculate the fingerprint in more detail. At block 1002 , the fingerprint ID service 123 receives an order from the adaptive engine 121 requesting a new or updated fingerprint. The fingerprint ID service 123 may also search the WIP database 128 to obtain the information that will be required to form the fingerprint, such as the entity ID, the units of work and their IDs, the unit placement, the device codes, feature bills of materials (BOM) and placement, and installed parts and placement. The fingerprint ID service 123 parses the request for the desired configuration level(s) at block 1004 and then selects the first configuration data element at block 1006 . Next, the fingerprint ID service 123 converts the configuration data element(s) into base-64 at block 1008 and then divides that result into 64 bit blocks at block 1010 . Some embodiments will pad the last block to ensure it has the full 64 bits. Next, at blocks 1012 - 1020 , the fingerprint ID service 123 will then compute a hash from the 64 bit blocks. Although the particular hash in described in FIG. 10 is desirable because it produces similar outputs for similar inputs, any known check-sum, message digest, or hashing algorithm that produces a unique result may be used. The resulting hash is returned at block 1022 as the fingerprint. [0051] FIG. 11 illustrates the operation of the rate/qualification based sampling strategy program 122 b in more detail. In operation, this program 122 b tracks for which systems or units of work a sampling operation is selected, and the corresponding attribute list is used to determine whether or not to sample this particular item. More specifically, at block 1102 , the RATE program 122 b receives a call asking it to evaluate the sampling strategy for an assembly 190 . The RATE program 122 b responds by first reviewing a routing map definition file for the next operation (i.e., the operation after the one that triggered the call) at blocks 1103 - 1104 . Next, at block 1106 , the RATE program 122 b determines if the next operation is a sampling operation. If not, it leaves the next operation in the routing map at block 1105 and exits; otherwise, the RATE program 122 b proceeds to block 1108 . [0052] At block 1108 , the RATE program 122 b determines if the next operation is a system level operation. If so, the RATE program 122 b then asks whether the previous operation completed the sampling strategy for any lower level assembly 190 (e.g., assembly 190 b in MFGN 190 a ) at block 1112 . If yes, then the RATE program 122 b skips the next operation at block 1110 to avoid dirty data in the population and then returns to block 1102 ; otherwise, the RATE program 122 b determines at block 1113 if the highest level for this assembly 190 had been previously selected. If no, then the RATE program 122 b determines whether a sampling operation should be performed at block 1115 (described in more detail with reference to FIG. 12 ), otherwise, if RATE program 122 b determined the highest level for this assembly 190 had been previously selected at block 1113 , the RATE program proceeds to block 1105 . [0053] At block 1120 , if an additional sampling operation was required by block 1115 , then the RATE program 122 b issues work orders requesting the tests be performed at block 1122 , updates the sample population data at block 1124 , and then proceed to block 1105 . If, however, an additional sampling operation was not required at block 1120 , then the RATE program 122 b proceeds to update the WIP database 128 with the new sample data at block 1130 and update the sample population data at block 1132 and block 1134 . That is, the RATE program 122 b logs that there was an assembly 190 that met the population requirements, or the RATE program 122 b logs the number sampled and indicates that the assembly 190 is marked but not yet complete. When the sampling completes, then the assembly 190 is updated again to reflect that fact. These two pieces of data are desirable to show how many were assemblies 190 were actually sampled and how many assemblies 190 were produced in total. Thus, using this information, the RATE program 122 b can access the percentage sampled already, etc. [0054] At block 1140 , if the RATE program 122 b determined at block 1108 that this was not a system level operation, then the RATE program 122 b determines whether the previous operation was the last defined for the sub-assembly 190 b , 190 c , etc. This decision may include querying the manufacturing history for the sub-assembly 190 b , 190 c , etc. If previous operation did complete the sub-assembly 190 b , 190 c , etc, then the RATE program 122 b determines at block 1142 whether the sub-assembly 190 b , 190 c , etc. was previously selected; otherwise the RATE program 122 b proceeds to block 1110 . [0055] If the sampling strategy determined at block 1142 that sub-assembly 190 b , 190 c , etc. was previously selected, then the RATE program 122 b proceeds to block 1105 , otherwise the RATE program 122 b proceeds to block 1115 and resolves the sub-assembly 190 b , 190 c , etc. [0056] FIG. 12 illustrates the operation of block 1115 in more detail. At block 1203 , the RATE program 122 b determines what type of sampling is requested by the call, and then selects matching sampling control records. Next, at block 1204 , the RATE program 122 b determines if any sampling programs have been previously set up. If so, then the RATE program 122 b determines if there are any remaining sampling control records (a table in which users identify what type of sampling to initiate, at what operation, for which products, and the corresponding sampling parameters, not shown) at block 1206 , otherwise the RATE program 122 b replies at block 1208 that ‘no sample’ is required and exits. If RATE program 122 b determined at block 1206 that sampling control records remain, then the RATE program 122 b selects the relevant sampling control records at block 1210 ; otherwise the RATE program 122 b replies that no sample is required at block 1208 and exits. [0057] At block 1214 , the RATE program 122 b determines whether ‘qualify’ or ‘rate’ sampling was specified. If ‘qualify’ was specified, then the RATE program 122 b determines at block 1216 whether the current sample count is less then the required sample value. This determination may include querying the sampling control records 1217 (a table in which users identify what type of sampling to initiate, at what operation, for which assemblies, and the corresponding sampling parameters) and a sample population information table 1219 (tracks sample population per attribute used in determining sample selection). If the current sample count is less then the required sample value, then the RATE program 122 b returns that ‘a sample is required’ at block 1218 ; otherwise, the RATE program 122 b iterates through the remaining bills of materials (BOM) for the assembly to determine if any remain at blocks 1220 - 1222 . If the sample count is less then the sample value and no remaining BOM's remain in the list, then the RATE program 122 b will return to block 1206 . [0058] If ‘rate’ was specified at block 1204 , then the RATE program 122 b determines at block 1230 whether the sample count/population size is less then the required sampling rate. If so, then the RATE program 122 b returns a sample required message at block 1218 , otherwise the RATE program 122 b iterates through the remaining bills of materials (BOM) for the assembly 190 to determine if any remain at blocks 1232 - 1234 . If the required rate has been satisfied and no remaining BOM's remain in the list, then the RATE program 122 b will return to block 1206 . [0059] Referring again to FIGS. 1A-1C , the computing system 100 in this embodiment comprises a plurality of central processing units 110 a - 110 d (herein generically referred to as a processor 110 or a CPU 110 ) connected to a main memory unit 112 , a mass storage interface 114 , a terminal/display interface 116 , a network interface 118 , and an input/output (“I/O”) interface 120 by a system bus 119 . The mass storage interfaces 114 , in turn, connect the system bus 119 to one or more mass storage devices, such as a direct access storage device 140 or a readable/writable optical disk drive 542 . The network interfaces 118 allow the computer system 100 to communicate with other computing systems 100 over the communications medium 106 . [0060] The computing system 100 in this embodiment is a general-purpose computing device. Accordingly, the CPU's 110 are capable of executing program instructions stored in the main memory 112 and are constructed from one or more microprocessors and/or integrated circuits. Moreover, in this embodiment, the computing system 100 contains multiple processors and/or processing cores, as is typical of larger, more capable computer systems. However, in other embodiments, the computing systems 100 may comprise, in whole or in part, a single processor system; a single processor designed to emulate a multiprocessor system; or special purpose processing devices, such as an application specific integrated circuit (ASIC). [0061] When the computing system 100 starts up, the associated processor(s) 110 initially execute the program instructions that make up the operating system 124 , which in turn, manages the physical and logical resources of the computer system 100 . These resources include the main memory 112 , the mass storage interface 114 , the terminal/display interface 116 , the network interface 118 , and the system bus 119 . As with the processor(s) 110 , some computer system 100 embodiments may utilize multiple system interfaces 114 , 116 , 118 , 120 , and busses 122 , which in turn, may each include their own separate, fully programmed microprocessors. [0062] The system bus 119 may be any device that facilitates communication between and among the processors 110 ; the main memory 112 ; and the interfaces 114 , 116 , 118 , 120 . Those skilled in the art will appreciate that the system bus 119 may be a relatively simple, single bus structure that provides a direct communication path among the system bus 119 (as depicted in FIG. 1A ), or may be a more complex structure, such as point-to-point links in hierarchical, star or web configurations; multiple hierarchical buses; parallel and redundant paths, etc. [0063] The main memory 112 and the mass storage devices 140 work cooperatively in this embodiment to store the operating system 124 , the MES 126 , the WIP database 128 , the sampling programs 122 . In this embodiment, the main memory 112 is a random-access semiconductor device capable of storing data and programs. Although FIG. 1A conceptually depicts this device as a single monolithic entity, the main memory 112 in some embodiments may be a more complex arrangement, such as a hierarchy of caches and other memory devices. Thus, for example, the main memory 112 may comprise multiple levels of caches, and these caches may be further divided by function, so that one cache holds instructions while another holds non-instruction data, which is used by the processor or processors. The memory may be further distributed and associated with different CPUs 110 or sets of CPUs 110 , as is known in any of various so-called non-uniform memory access (NUMA) computer architectures. Moreover, some embodiments may utilize virtual addressing mechanisms that allow the computing systems 100 to behave as if it has access to a large, single storage entity instead of access to multiple, smaller storage entities such as the main memory 112 and the mass storage device 140 . [0064] Moreover, while the operating system 124 , the MES 126 , the WIP database 128 , and the sampling programs 122 are illustrated as being contained within the main memory 112 , some or all of them may be physically located on different computer systems and may be accessed remotely, e.g., via a communications medium, such as the Internet. That is, while the operating system 124 , the MES 126 , the WIP database 128 , and the sampling programs 122 are illustrated as being contained within the main memory 112 , these elements are not necessarily all completely contained in the same physical device at the same time, and may even reside in the virtual memory of other computer systems 100 . Such arrangements are common in virtualized and cloud-based embodiments. [0065] The system interface units 114 , 116 , 118 , 120 support communication with a variety of storage and I/O devices, including the managed stations 191 . More specifically, the mass storage interface unit 114 supports the attachment of one or more mass storage devices 140 , which are typically rotating magnetic disk drive storage devices, although they could alternatively be other devices, including arrays of disk drives configured to appear as a single large storage device to a host and/or archival storage media, such as hard disk drives, tape (e.g., mini-DV), writeable compact disks (e.g., CD-R and CD-RW), digital versatile disks (e.g., DVD, DVD-R, DVD+R, DVD+RW, DVD-RAM), holography storage systems, blue laser disks, IBM Millipede devices and the like. [0066] The terminal/display interface 116 directly connects one or more display units 199 to the computer system 100 . These display units 180 may be non-intelligent (i.e., dumb) terminals, such as a cathode ray tube, or may themselves be fully programmable workstations used to allow IT administrators and users to communicate with the computing system 100 . Note, however, that while the interface 116 is provided to support communication with one or more displays 180 , the computer systems 100 does not necessarily require a display 180 because all needed interaction with users and other processes may occur via network interface 118 . [0067] The communications medium may be any suitable network or combination of networks and may support any appropriate protocol suitable for communication of data and/or code to/from multiple computing systems 100 . Accordingly, the network interfaces 118 can be any device that facilitates such communication, regardless of whether the network connection is made using present day analog and/or digital techniques or via some networking mechanism of the future. Those skilled in the art will appreciate that many different network and transport protocols can be used to implement the network. The Transmission Control Protocol/Internet Protocol (“TCP/IP”) suite contains suitable network and transport protocols. [0068] The computing system 100 in FIGS. 1A-1C is depicted with multiple attached terminals 180 , such as might be typical of a multi-user “mainframe” computer system. In such a case, the actual number of attached devices is typically greater than those shown in FIG. 1A , although the present invention is not limited to systems of any particular size. The computing systems 100 may alternatively be a single-user system, typically containing only a single user display and keyboard input, or might be a server or similar device which has little or no direct user interface, but receives requests from other computer systems (clients). One exemplary computing system 100 is the IBM Power® platform running the i5/OS® multitasking operating system, both of which are available from International Business Machines Corporation of Armonk, N.Y. However, those skilled in the art will appreciate that the methods, systems, and apparatuses of the present invention apply equally to any computing system 100 and operating system combination, regardless of whether one or both of the computer systems 100 and terminals 180 are complicated multi user computing apparatuses, a single workstations, lap-top computers, mobile telephones, personal digital assistants (“PDAs”), video game systems, embedded computer systems, appliances, tablet computer, pocket computer, telephone, pager, automobile, teleconferencing system, appliance, or any other appropriate type of electronic device, or the like. [0069] Although the present invention has been described in detail with reference to certain examples thereof, it may be also embodied in other specific forms without departing from the essential spirit or attributes thereof. For example, those skilled in the art will appreciate that the present invention is capable of being distributed as a program product in a variety of forms, and applies equally regardless of the particular type of computer-readable signal bearing medium used to actually carry out the distribution. Examples of tangible, computer-readable signal bearing media include, but are not limited to: (I) read-only storage media (e.g., read only memory devices (“ROM”), CD-ROM disks readable by a CD drive, and Digital Versatile Disks (“DVDs”) readable by a DVD drive); (ii) writable and rewriteable storage media (e.g., floppy disks readable by a diskette drive, CD-R and CD-RW disks readable by a CD drive, random access memory (“RAM”), and hard disk drives). Examples of communication signal bearing media include, but are not limited to: (i) computer networks, such as those implemented using “Infiniband” or IEEE 802.3x “Ethernet” specifications; (ii) telephone networks, including cellular transmission networks; and (iii) wireless networks, such as those implemented using the IEEE 802.11x, IEEE 802.16, General Packet Radio Service (“GPRS”), Family Radio Service (“FRS”), and Bluetooth specifications). Those skilled in the art will appreciate that these embodiments specifically include computer software downloaded over the Internet. [0070] The present invention may also be embodied part of a service engagement with a client corporation, nonprofit organization, government entity, internal organizational structure, or the like. Aspects of these embodiments may include configuring a computer system to perform, and deploying software, hardware, and web services that implement, some or all of the methods described herein. Aspects of these embodiments may also include analyzing the client's operations, creating recommendations responsive to the analysis, building systems that implement portions of the recommendations, integrating the systems into existing processes and infrastructure, metering use of the systems, allocating expenses to users of the systems, and billing for use of the systems. These service engagement embodiments may be directed at providing complete manufacturing solutions, to providing only information services, or some combination thereof. [0071] The accompanying figures and this description depicted and described embodiments of the present invention, and features and components thereof. Those skilled in the art will appreciate that any particular program nomenclature used in this description was merely for convenience, and thus the invention should not be limited to use solely in any specific application identified and/or implied by such nomenclature. Thus, for example, the routines executed to implement the embodiments of the invention, whether implemented as part of an operating system or a specific application, component, program, module, object, or sequence of instructions could have been referred to as a “program”, “application”, “server”, or other meaningful nomenclature. Indeed, other alternative hardware and/or software environments may be used without departing from the scope of the invention. Likewise, reference to “the invention” shall not be construed as a generalization of any inventive subject matter disclosed herein and shall not be considered to be an element or limitation of the appended claims except where explicitly recited in a claim(s). Therefore, it is desired that the embodiments described herein be considered in all respects as illustrative, not restrictive, and that reference be made to the appended claims for determining the scope of the invention.

A method for dynamically altering manufacturing routings to add, remove, or skip operations and combinations of operations within a shop floor control system in real-time to respond to current conditions. One aspect of the present invention is a computer-implemented method for dynamically generating a manufacturing production work flow. One embodiment of this method comprises receiving indication that an assembly has completed a manufacturing operation, the assembly having a work flow and a sampling strategy associated therewith; querying a data source for characteristics of a plurality of previously sampled components; querying a manufacturing floor control system for current production status; and dynamically updating the work flow for the assembly based at least in part on the sampling strategy, characteristics of the plurality of previously sampled components, and the current production status.

This is a continuation of application Ser. No. 214,879, filed July 5, 1988, which is a continuation of Ser. No. 029,388, filed Mar. 23, 1987, now abandoned, which is a continuation of Ser. No. 650,263, filed Sept. 13, 1984, now abandoned. TECHNICAL FIELD The invention relates to an infrared detector, and in particular to a thermal detector. Infrared radiation absorbed by a thermal detector produces a rise in temperature of the detector material. The detector material is selected to have a temperature dependent property affected by temperature change, and this property is monitored to provide a signal indicating the infrared intensity illuminating the detector. Thermal detectors are distinguishable from photodetectors, also referred to as photon detectors and also used for infrared detection. In a photon detector, radiation absorbed excites electronic transitions within the detector material producing a signal arising from the changed electronic energy distribution. Photoconductive and photovoltaic detectors operate in this way. For detection of infrared wavelengths longer than 3 μm, cooling is normally required to reduce thermally induced transitions so that photon-induced transitions predominate. BACKGROUND ART Pyroelectric materials are known for use as thermal detectors. The internal electrical polarisation of a pyroelectronic material changes rapidly with temperature in the region of its Curie temperature. Single-element pyroelectric detectors have been used as infrared detectors in burglar alarms, radiometers and the like. The pyroelectric material is arranged as a capacitor dielectric, and an electrical signal across the capacitor is monitored for changes arising from dielectric property variation with temperature affected by infrared absorption. Reticulated multi-element arrays of pyroelectric detectors are also known, in for example the pyroelectric vidicon tube. In this device the pyroelectric material is scanned with an electron beam to read out the varying surface charge pattern induced by infrared emission from a scene. The electrical current in the tube circuit is dependant on the polarisation charge on the detector surface at the point addressed by the electron beam. A pyroelectric material for a thermal detector is selected to have its Curie temperature at about ambient temperature to permit operation without cooling. Sensitivity is a function of pyroelectric properties. Unfortunately, no improvement in performance can be obtained by cooling; performance can in fact worsen with cooling if the material is taken far from its Curie point. Compounds with suitable pyroelectric properties are comparatively expensive to make in the form of detector quality slices of pyroelectric material suitable for detector arrays. Moreover, the required signal read-out apparatus is complex. The pyroelectric vidicon tube for example requires a comparatively bulky vacuum tube containing an electron gun and an arrangement of beam deflection and current collection electrodes. The electron beam produces an undesirable degree of electrical noise. Generally speaking, photon detectors are more sensitive than pyroelectric thermal detectors. However, for high sensitivity applications cooling to cryogenic temperatures (77° K.) is required, resulting in an undesirably bulky, complex and expensive arrangement. Simple thermoelectric cooling devices of acceptable power requirements are not adequate to give the necessary degree of cooling. Joule-Kelvin effect coolers are required. Photovoltaic devices such as photodiodes and Schottky photoemitters are known, these being usually operated at low and stable temperature. They accordingly normally consist of comparatively thick semiconductor material in intimate thermal contact with a heat sink and cooler. This minimizes and maintains constant unwanted thermally induced transitions. DISCLOSURE OF THE INVENTION It is an object of the present invention to provide a thermal detector capable of: (a) inexpensive production singly or in arrays, (b) comparatively simple read-out, and (c) operation at ambient temperature or with increased sensitivity at low temperature. The present invention provides a thermal detector including: (1) a sensing element comprising a semiconductor device of thin film construction having at least one pn junction, (2) a thin layer of infrared absorptive material in intimate thermal contact with the sensing element, and (3) a sensing element support of low thermal conductance. The detector of the invention is capable of inexpensive production since thin film semiconductor devices can be made singly or in arrays by known thin film technology, and this applies also to the associated infrared absorptive material. Provision of the support presents no difficulty. The detector of the invention is operative at ambient temperature, or at low temperature if increased sensitivity is required. The cooling requirements are less than those necessary for photon detectors, a simple thermoelectric cooler normally sufficing. As will be described later in more detail, signal read-out is comparatively simple compared to read-out from pyroelectric devices. In view both of the thin film construction of the sensing element and associated absorptive material, and of the thermal isolation provided by the low conductance support, the element and absorptive material have low thermal capacity and rapidly follow temperature changes in a scene. The sensing element may be a bipolar transistor or a junction diode. The diode may be of the light emitting (LED) variety. In the case of a transistor, the sensing element may also act as a preamplifier and read-out device in addition to storage properties arising from the thermal time constant. The preamplifier function arises from normal transistor properties, and read-out may be provided for by employing means for pulsing the transistor base voltage appropriately. Alternatively, the transistor may be supplemented by a switching transistor inserted in its emitter-collector circuit. To further advantage, the transistor may be combined with a shielded dummy transistor in a long-tailed pair configuration affording adaptive threshold subtraction. An LED provides light output which is a function of temperature. The light output may be monitored by any conventional means. In a preferred embodiment of the invention, the sensing element has a thickness less than 10 μm and is formed of semiconductor material having a band gap greater than 1 eV, e.g. Si, GaAs, GaAlAs or GaP. In addition, the sensing element has a thermal conductance less than 0.4 W/K cm 2 . The support may be of silicon oxide foam glass or foam plastics material. Thermal conduction between the sensing element and the support may be inhibited by partly relieving the support surface. In a further embodiment, there is provided an array of detectors each in accordance with the invention hereinbefore disclosed. The array preferably includes a plurality of sensing elements of reticulated thin film construction. BRIEF INTRODUCTION OF THE DRAWINGS In the drawings that accompany this specification: FIG. 1 is a cross-section showing the structure of a single element thermal detector, an embodiment of this invention; FIG. 2 is a circuit diagram for the detector of FIG. 1 above; FIGS. 3(a)-(d) are cross-sections showing various stages in the manufacture of the detector of FIG. 1 above; FIGS. 4 and 5 shown in cross-section and plan-view the structure of a multi-element array thermal detector, also an embodiment of this invention; FIG. 6 is a circuit diagram for the array detectors of FIGS. 4 and 5 above; and FIGS. 7 and 8 are circuit diagrams of alternative long-tail pair transistors that may be substituted for the single transistors shown in FIGS. 2 and 6 above. DESCRIPTION OF PREFERRED EMBODIMENTS Below are given expressions describing the performance characteristics derived for a simple thermally insulated diffusion limited bipolar transistor, a thin film sensing element mounted upon a low thermal conductance support. Similar considerations also apply to the performance characteristics of a junction diode, whether a homojunction or heterojunction device. In a diffusion limited bipolar transistor the current-voltage (I-V) characteristics for the emitter-base junction are of the form: ##EQU1## where: V b (volts) is the emitter-base voltage; T T (K) is the absolute temperature of the junction; q (Coulomb) is the electron charge constant; k B (J.K -1 ) is the Boltzman constant; and I O (T) is a current parameter strongly dependent upon temperature. At temperatures above the intrinsic temperature characteristic of the material, this expression reduces to ##EQU2## where Eg (electron-volts) is the energy band-gap of the transistor material. The responsivity R I λ of the transistor detector, i.e. the rms signal current ΔI per unit rms radiant power ΔP upon the detector is thus given by the following expression: ##EQU3## where G (Watt/K) is the thermal conductance of the detector. In deriving an expression for the detector conductance G, the contribution of the thin film transistor (which is of higher conductivity material than that of the supporting mounting) can be ignored to a first approximation: ##EQU4## where: A (cm 2 ) is the area of the transistor element in contact with the supporting mounting; d (cm) thickness of the mounting; k T (Watt/cm.K) is the thermal conductivity of the mounting; ρ s (J/cm 3 K) is the volume specific heat of the mounting; and, F (Hz) is a sampling frequency. The optimum thickness d o of the support is given when the two terms of the conductance are equal, and the conductance is therefore a minimum ##EQU5## The detectivity of this device will now be derived: The minimum detector power (noise equivalent P Nd is given by: P.sub.Nd =(4 k.sub.B T.sup.2 G).sup.1/2 E. 5 The current noise i na of the transistor must also be considered: i.sub.na =(2qI).sup.1/2 . . . Amp/Hz-1/2 and the corresponding noise power P Na : P.sub.Na =(2qI).sup.1/2 /R.sub.Iλ E. 6 For a transistor of sensible construction, the contribution of partition (1/f) noise may be ignored to first approximation, the total noise equivalent power P N is thus given by the rms summation: P.sub.N =[P.sub.Nd.sup.2 +P.sub.Na.sup.2 ].sup.1/2 E. 7 Thus the normalised detectivity D* defined as: ##EQU6## is given by: ##EQU7## In the high current limit, where the detector noise is dominant, i.e.: ##EQU8## this expression for the normalised detectivity reduces to: ##EQU9## In general it can be said of the device that the responsivity is optimal at high current, low temperature, and with minimal support conductance. The detectivity is optimal for low temperature and with minimal support conductivity. Examples are now given: EXAMPLE 1 A thin film silicon transistor 50 μm square, supported on a solid layer support of silicon oxide of optimal thickness and maintained in an enclosure held at room temperature (300 K.): Eg=1.12 eV; k.sub.T =0.014 W/cm.K.; ρ.sub.s =0.03 J/cm.sup.3 K; d.sub.o =63 μm Operating with a gate volta V b =0.687 volts, a standing collector current I of 10 Amp and sampling frequency of 25 Hz: ##EQU10## Taking radiant power density as 2×10 -4 Watt/cm.K over 8-12 μm wavelength IR band: ΔT.sub.junction 10.sup.-4 K/K temperature change ΔT' in thermal scene. ##EQU11## D*.sub.300 =1.5×10.sup.8 cmHz1/2Watt.sup.-1 This may be compared to the detectivity pertaining in the case of ideal thermal isolation and where heat transfer is by radiation only, this representing the theoretical limit: D.sub.R *=(16 σk.sub.B T.sup.5).sup.-1/2 =1.8×10.sup.10 cmHz1/2Watt.sup.-1. EXAMPLE 2 As in example 1, but at reduced temperature (77 K.) Eg=1.15 eV V.sub.b =1.017 v. Evaluation of the above expressions gives: ##EQU12## D*.sub.77 =2.3×10.sup.9 W cm.sup.-1 EXAMPLE 3 A thin film silicon transistor 50 μm square, supported on a solid layer support of foam glass. k.sub.T =300 μW/cm.K; ρ.sub.s =600 μWatt/cm.K; d.sub.o =63 μm. Evaluation of the above expressions gives: ΔT/ΔT'≃5×10.sup.-3 K/K ##EQU13## D*.sub.300 =7×10.sup.9 cmHz1/2Watt.sup.-1 It is noted that yet further improvement in detectivity is attainable by reducing the support conductance--e.g. by etching away part of the support surface underlying the transistor. Further improvement in responsivity is also attainable, for example, by using in place of silicon a material of higher energy band-gap--e.g. gallium arsenide (Eg=1.4 eV @ 300 K.) for which the intrinsic carrier concentration varies more rapidly with temperature. Further embodiments of the invention will now be described, by way of example only, with reference to the drawings accompanying the specification. A single element detector 1 is shown in cross-section in FIG. 1 and the equivalent circuit, a conventional common-emitter transistor circuit, is shown in FIG. 2. The detector 1 is comprised of a thin monocrystalline film 3 of n-type silicon material, bonded to the surface of a low thermal conductance substrate 5 of silicon oxide. The thicknesses t and d o respectively, of the film and the substrate, are approximately 2 μm and -60 μm. The substrate 5 is bonded to the surface of a high thermal capacity metal shield 7, which during operational conditions is maintained at a constant temperature. P- and N-type diffusions have been introduced in the silicon film 3, to define the emitter e, base b, and collector c regions, of an n-p-n transistor structure T and resistive contact leads, for example tracks of polysilicon (not shown) have also been provided. Part of the silicon film 3 has been recessed 9 by photolith etch definition to delineate the area of the transistor sensor T and to minimise lateral thermal diffusion. The sensor T is square of side 1 of dimension 2 mm and serves thus as a large area detector. A thin low thermal conductance infrared absorptive layer 10 of e.g. graphite or a metal dispersion--gold-black or the like, is formed over the surface of the sensor T. The collector voltage and base voltage supply lines V cc , V b are shown in FIG. 2, as also a load resistor R L between the collector c and the collector voltage line V cc . Preamplifier transistors may be formed in the silicon film 3 at the periphery of the sensor T. FIG. 3 serves to illustrate the process steps adopted during the manufacture of the detector 1 just described. In the first stage of this process (see FIG. 3(a)) a thin film epitaxial layer 3 of n-type silicon is grown upon the clean planar surface of a good quality monocrystalline substrate 11 of p-type silicon. This latter is of conventional thickness ˜200 μm. P- and N-type diffusions are then formed to define the transistor structure. At this stage all other peripheral transistor structures may also be defined (see FIG. 3(b)). Following this stage, the substrate 11 is removed by means of a p-n selective etchant, and the film 3 bonded upon the low conductance substrate 5 which may be of silicon oxide, foam glass or foam plastics material of appropriate optimal thickness. The film 3 is then reticulated 9, following photolith pattern definition, using an appropriate etchant (see FIG. 3(c)). An inter-connect pattern of polysilicon resistive leads 13, 15 and 17 together with contact pads at the detector periphery are then defined (see FIG. 3(d)), and absorbtive material deposited. It will be understood, that given appropriate low conductance substrate material and process temperatures, the order of the steps recited above may be rearranged as is convenient. It is also possible to construct multi-element array detectors employing the technical process above described. A typical example of such an array detector is shown in cross-section and plan in FIGS. 4 & 5. As shown, the silicon film 3 is mounted upon an etched low conductance substrate 5, the latter having been etched to form a support structure with no more than minimal thermal contact with the film, enough to provide adequate mechanical support. The film 3 has been reticulated and transistor structures T 11 , T 12 . . . have been formed in row and column two-dimensional array. Each transistor sensor T 11 , . . . T nm is of size 50 μm square. The operational circuit for this array detector is shown in FIG. 6. The interconnection pattern is such that for each row of transistors e.g. T 11 , T 12 , . . . T 1m the base contacts b are connected to a corresponding common row address line. For each column of transistors e.g. T 12 , T 22 , . . . T n2 the collector contacts c are connected to a corresponding common column output line, one end of which is connected to the collector volta V cc supply line via an active resistive load R L . Each column output line is tapped above the resistive load R L to provide connection to a corresponding one of a number of preamplifiers A 1 , A 2 , . . . , A m . The output of each amplifier is connected to a multiplexer 21 and a line signal is provided at output O/P. Each row of transistors is pulsed once each frame. A typical frame interval being 40 msec (i.e. sample freq. f=25 Hz). The switch pulses are fed from an address circuit 23, for example a shift register. In this arrangement each transistor T 11 to T nm thus serves not only as a sensor of thermal radiation, but as an integrating store between each pulse, and, as a switch on each pulse. In a modification of the above array circuit for each transistor T 11 to T nm an additional transistor could be inserted between collector and output line and connected at its base to the corresponding address line. The base b of each sensing transistor is then instead connected to a common gate voltage line. The signal current is then drawn by switching on collector voltage for the sensing transistors rather than using the sensing transistor as its own switch. Alternatively, both base and collector could be addressed to allow co-ordinate selection. Standing current bias in the measured signal may be removed by using a chopper to interrupt the radiation falling upon the array and subtracting alternate frame signals. An alternative approach is to employ matched, paired, transistors e.g. T 1 , T 2 in long-tail pair configuration as shown in FIG. 7. One transistor T 1 is masked from the thermal radiation, a reflecting metal shield being mounted over the transistor. Each transistor is referred to a common base voltage and switching is performed by an additional transistor T G interposed in the emitter circuit. A similar circuit is shown in FIG. 8, but here each transistor T 1 and T 2 is referred to a different collector voltage line V c1 , V c2 via different resistive loads R 1 , R 2 . In this arrangement, the dummy transistor T 1 may be of significantly smaller geometry and designed to occupy significantly less space in the detector plane. This then allows a greater packing density in sensing elements with consequent improvement in spatial resolution. The transistor circuits used for line and co-ordinate address above could be arranged in common base or common collector configuration. Active feedback could also be introduced. It will be appreciated that the array address that may be used is not restricted to the direct address schemes as described above. The examples of the invention hereinbefore described of transistor sensing elements provide the advantages that the sensing element may act as its own preamplifier, read-out device or switch, and integrating store, as previously indicated. The preamplifier function arises from the transistor property of amplification and impedance conversion, and the storage function from thermal time constant effects common to all thermal detectors. In applications for which preamplification or read-out is not required to be incorporated in the sensing element, the sensing element may be a pn junction diode produced singly or in arrays. The current-voltage or I-V characteristics of a pn junction vary with temperature (and thus infrared radiation received from a scene) as follows from E.2: ##EQU14## Monitoring the current in the diode when biassed accordingly provides a measure of the infrared radiation received by the diode. The diode or diode array is produced similarly to the transistor embodiments, i.e. in thin film form with an associated infrared absorption layer and low conductance support. Since only two leads are required per diode, thermal conduction along leads to each diode is less than for a transistor; only one per junction is required, so the device is thinner with lower thermal capacity. If the diode is of the light-emitting variety (LED), the intensity of the LED light emission is a function of temperature. A thin film (˜2 μm) pn junction LED thermally isolated as previously described for transistors will change in temperature in accordance with the intensity of infrared radiation it receives. The temperature change produces a corresponding change in the LED operating point in its I-V characteristic. Necessarily, an attendant change in the LED emission intensity occurs which may be monitored by conventional means. Group III-V semiconductor LEDs incorporating Ga emit light in the visible or near infrared, since their band gaps are above 1 eV. Detection of their light emission with adequate sensitivity is a much simpler problem than detecting infrared light of wavelength 3 μm or longer. Furthermore, materials such as GaAs and GaP used for LEDs have wider band gaps than Si, and this enhances responsivity (see E.2). A planar reticulated array of LEDs of similar construction to earlier embodiments of the invention may be employed as a detector. One side of the array receives infrared radiation from a scene, and light is emitted from the reverse side. A change-coupled device (CCD) camera of known kind may be employed to monitor light emission and provide an electrical output. Optical outputs from individual diodes of the detector array appear in parallel--i.e. simultaneously. The diode output is optically coupled to monitoring means, so there is no requirement for output connection leads which increase thermal conduction and worsen thermal isolation of the detector. The diodes may be pulsed for operation at high current levels to increase responsibility. From E.2, R I λ ∝I, so that high pulsed current but low average current produces high responsivity without an unacceptable degree of diode heating.

A thermal detector comprises a thin film diode transistor coated with infrared absorbent material, and mounted on a thermally insulating support such as silicon oxide, foam glass or foam plastics material. The support may be recessed to improve insulation. The detector may be an array of diodes or transistors, and the diodes may be LEDs. Addressing may be line-by-line or co-ordinate selection. A transistor detector array may be arranged for signal integration and sample switching. A chopper may be used to modulate radiation illuminating the detector, whose output is fed to subtractive circuitry. Alternatively, a transistor detector array may incorporate additional transistors for bias current subtraction, each detecting transistor forming a long-tailed pair configuration with a respective additional transistor.

The present invention relates to the liquid phase separation of mixtures of lactulose and lactose. More particularly, it relates to such a separation by selective adsorption on certain types of zeolite molecular sieves. Lactulose is a disaccharide sugar constituted of galactose and fructose which has properties of considerable interest in the medical and food industries. It may be formed by converting lactose, another disaccharide, to lactulose by isomerization. Lactose is a disaccharide formed by linking two six-carbon sugars, glucose and galactose. Lactose can be converted into lactulose by catalysis by bases, alkali or alkaline earth borates or aluminates, ion exchange resins, or enzymes. Because the reaction is usually incomplete, the reaction products are mixtures of lactose and lactulose. For many medical or food industry uses, the lactulose must be separated from such mixtures. There is one diclosed method to separate lactose and lactulose using selective adsorption: Japanese Kokai No. 77-71409 (Odawara). Odawara teaches the use of an X- or Y-type zeolite substituted with alkaline earth metal ions (preferably calcium, strontium or barium) to separate the components of the mixture. Barium-substituted Type X (BaX) zeolite adsorbs neither lactulose nor lactose significantly. Calcium-substituted Type Y zeolite does not adsorb lactulose particularly strongly. As a result, the calcium-substituted Type Y zeolite is not particularly effective in separating the two sugars in that much of the lactulose contains quantities of lactose, rendering it impure. In the case of barium-substituted Type Y zeolite, the rate of approach to adsorption equilibrium is very slow, requiring a low process flow rate (approximately 0.072 gpm/ft 2 ). At such a low flow rate, the adsorption/desorption cycle time is very long. Thus, the capital investment for the separation process is not efficiently utilized. Another disadvantage to using barium-substituted Y-type zeolite (hereinafter referred to as "BaY") is the presence of barium ions on the zeolite. Although the feed solution containing lactose and lactulose may also contain a variety of cations, it is unlikely that barium ions will be among them. Therefore, as the feedstock travels through the zeolite, the barium ions will tend to be lost from the zeolite and leach into the product stream. This would, in turn require removal of barium ions from the product as well as either adding them to the feed stream in order to prevent loss of barium ions from the zeolite or periodic addition of ions to the zeolite to replenish the supply on the zeolite. Since the sugar adsorption is cation-specific, it might be expected that a zeolite containing a larger number of cations would exhibit stronger affinity for adsorbates than a zeolite with a smaller number of cations. It is also expected that zeolites with stronger affinity for sugars would have poor counterdiffusion rates (see Table I for retention volumes which reflect adsorption affinities of zeolites.) It has been discovered that potassium-exchanged zeolites with framework structures similar to that of the Y-type zeolite, but with much lower ion concentrations than either X- or Y-type zeolites (i.e., "modified Type Y zeolite"), separate lactose and lactulose better than KY. Furthermore, the barium form of this modified Y-type zeolite not only provides longer retention times than conventional barium-exchanged Y-type zeolites, but also unexpectedly exhibited greatly improved rates of adsorption and desorption. BRIEF DESCRIPTION OF FIGURES FIG. 1 shows the separation of lactose and lactulose by a conventional Type-Y zeolite which has been barium-exchanged. FIG. 2 shows the separation of lactose and lactulose by a steam-modified Type-Y zeolite which has been barium-exchanged. FIGS. 3 and 4 show separations of lactose and lactulose using steam-modified zeolite Type Y which has been potassium-exchanged. FIG. 5 represents one typical embodiment of the process of the present invention. DESCRIPTION OF THE INVENTION The present invention comprises a process for separating lactulose from admixture with lactose by selective adsorption which comprises contacting a mixture comprising said compounds at a temperature of from 30° C. to 100° C. and at a pressure sufficient to maintain the system in the liquid phase with an adsorbent composition comprising at least one crystalline aluminosilicate zeolite selected from a group consisting of modified Type Y zeolite having a cation site concentration of from about 40 to about 10 equivalents per mole unit cell and a face centered cubic unit cell having an a o (for the decationized form; e.g., after steaming and before further cation exchange) of from 24.3 to 24.6 A, in which the zeolitic cations are more than 50% barium or potassium, whereby lactulose is selectively adsorbed thereon; removing the non-adsorbed portion of said mixture from contact with the zeolite adsorbent; and desorbing the lactulose therefrom by contacting said adsorbent with a desorbing agent and removing the desorbed lactulose. Zeolite Y and the method for its manufacture are described in detail in U.S. Pat. No. 3,130,007, issued Apr. 21, 1964 to D. W. Breck. It is preferred that the modified Type Y zeolite be prepared in accordance with the method disclosed in British Pat. No. 1,506,429, published Apr. 5, 1978. This process comprises heating an ammonium-exchanged Type Y zeolite at a temperature between 550° and 800° C. for a period of at least 0.25 hours in pure steam or an inert atmosphere comprising a substantial amount of steam (at least 2 psia and preferably 1 atm of steam), removing at least a major proportion, preferably all, of any ammonia generated by the heated zeolite from contact with the zeolite, and cooling the steamed zeolite to a temperature below 350° C. and preferably below 300° C. The final product can be characterized by a o values (for the decationized form; e.g., after steaming and before further cation exchange) between about 24.3 and about 24.6 A and cation concentrations of from 40 to 10 equivalents per mole unit cell. It is believed that steaming causes an alteration of the zeolite framework so as to reduce the framework aluminum content with a concommitant decrease in cation exchange capacity. Therefore, it is expected that, while the steaming method is preferred, other methods for modifying Type Y zeolites so as to reduce cation exchange capacity will produce zeolites with separation capabilities similar to those of the steamed zeolites. The adsorption affinities of various zeolites for sugars was determined by a "pulse test". This test consisted of packing a column with the appropriate zeolite, placing it in a block heater to maintain constant temperature, and eluting solutions through the column to determine retention volume of solute. The retention volume of solute is defined as elution volume of solute minus "void volume". "Void volume" is the volume of solvent needed to elute a non-sorbing solute through the column. A soluble polymer of fructose, inulin, which is too large to be sorbed into the zeolite pores, was chosen as the solute to determine void volume. The elution volume of inulin was first determined. The elution volumes of sugars were then determined under similar experimental conditions. The retention volumes were calculated and are recorded in Table I, below. From the retention volume data, the separation factor (S.F.), (α lactulose)/(lactose), was calculated in accordance with the following equation: ##EQU1## An α value greater than unity indicates that the particular adsorbent was lactulose-selective. The separation factor values calculated according to the above-mentioned method are found in Table II. It is apparent from Table II that the barium- and potassium-substituted modified Zeolite Y are lactulose-selective. Barium-substituted conventional zeolite X and potassium substituted conventional zeolite Y provided no separation whatsoever. TABLE I______________________________________RETENTION VOLUME OF SUGARS(in ml)Flow Rate: 1 ml/min.Temp: 70° C.Elution peak was detected by differential refractometerColumn Dimension: 40 cm × 0.77 cm (ID)Zeolite Inulin Lactose Lactulose______________________________________BaX 0 0.04 0BaY 0 1.7 3.1BaSY 0 3.5 5.8KY 0 2.0 2.0KSY 0 2.3 3.5______________________________________ TABLE II______________________________________SEPARATION FACTORS FOR LACTULOSE/LACTOSE SEPARATION LACTULOSEZEOLITE .sup.α LACTOSE______________________________________BaX 1.0BaY 1.82BaSY 1.66KY 1.00KSY 1.52______________________________________ Another parameter which is important in determining the overall separation efficiency of the zeolite used in the process of this invention is the "R-factor". This factor is often used to determine separation efficiency because it takes into account the rate of diffusion through the zeolite as well as selectivity, or adsorption affinity. The R-factor is defined as follows: ##EQU2## where the peak width is measured at half-height of the peaks of elution curves which measure concentration versus elution volume. Referring to FIG. 1, the calculated R-factor is 0.34 for barium-substituted zeolite Type Y. In comparison, the calculated R-factor for barium-substituted modified zeolite Type Y, as determined from FIG. 2, is 1.14. Thus it can be seen that the modified zeolite has superior overall separation characteristics, despite its stronger affinity for lactose and lactulose. In separating lactulose and lactose in the present process, a bed of solid zeolite adsorbent is contacted with a feed mixture, the lactulose is preferentially adsorbed on the adsorbent, the unadsorbed or raffinate mixture is removed from the adsorbent bed, and the adsorbed lactulose is desorbed from the zeolite adsorbent. The adsorbent can, if desired, be contained in a single bed, a plurality of beds in which conventional swing-bed operation techniques are utilized, or a simulated moving-bed countercurrent type of apparatus. The preferred mode of operation is the simulated moving-bed technique such as that described in U.S. Pat. No. 2,985,589 issued May 23, 1961 to D. B. Broughton et al. In this method of operation, the selection of a suitable displacing or desorbing agent or fluid (solvent) must take into account the requirements that it be capable of readily displacing absorbed lactulose from the adsorbent bed and also that lactulose from the feed mixture be able to displace adsorbed desorbing agent from a previous desorption step. Further, the desorbing agent employed should be readily separable from admixture with the sugar components of the feedstock. Therefore it is contemplated that a desorbing agent having characteristics which allow it to be easily fractionated from the sugars should be used. For example, volatile desorbing agents should be used, such as alcohols, ketones, admixtures of alcohols and water, particularly methanol and ethanol. The most preferred desorbing agent which can be used in the present process is water. Of the particular above-enumerated zeolites, barium-substituted modified zeolite Y (BaSY) is found to be most advantageous in this process. It has been found to have high selectivity for lactulose and to impart no serious rate (diffusion) or catalytic problems to the separation process. Also preferred is the use of potassium-substituted modified zeolite Y (KSY). Potassium salts may be used as catalysts in the conversion of lactose to lactulose and therefore may be present in the feedstock. If a potassium-substituted zeolite is used for separation, the potassium ions will not leach into the product during the process. This eliminates the need for regeneration of the zeolite. While it is possible to utilize the activated adsorbent zeolite crystals in a non-agglomerated form, it is generally more feasible, particularly when the process involves the use of a fixed adsorption bed, to agglomerate the crystals into larger particles to decrease the pressure drop in the system. The particular agglomerating agent and the agglomeration procedure employed are not critical factors, but it is important that the bonding agent be as inert toward the lactulose, lactose and the desorbing agent as possible. The proportions of zeolite and binder are advantageously in the range of 4 to 20 parts zeolite per part binder on an anhydrous weight basis. The temperature at which the adsorption step of the process should be carried out should be from about 30° C. to about 100° C. It has been found that at temperatures below about 30° C. the counter-diffusion rate between lactulose and lactose is too slow, i.e., a sufficient selectivity for the lactulose is not exhibited by the zeolite. Above about 100° C. the sugars tend to degrade. Preferably, the adsorption step should take place between about 60° C. and about 80° C. Pressure conditions must be maintained so as to keep the system in liquid phase. Thus, higher process temperatures needlessly necessitate high pressure apparatus and increase the cost of the process. In the drawings FIG. 5 represents a hypothetical moving-bed countercurrent flow diagram involved in carrying out a typical process embodiment of the present invention. With reference to the drawing, it will be understood that whereas the liquid stream inlets and outlets are represented as being fixed, and the adsorbent mass is represented as moving with respect to the counterflow of feedstock and desorbing material, this representation is intended primarily to facilitate describing the functioning of the system. In practice the sorbent mass would ordinarily be in a fixed bed with the liquid stream inlets and outlets moving with respect thereto. Accordingly, a feedstock consisting essentially of a mixture of 10 weight percent lactulose and 24 weight-percent lactose is fed into the system through line 10 to adsorbent bed 12 which contains particles of activated zeolite KSY or BaSY adsorbent in transit downwardly therethrough. The temperature is at 70° C. throughout the entire system and the pressure is substantially atmospheric. The lactulose component of the feedstock is adsorbed preferentially on the zeolite particles moving through bed 12, and the raffinate lactose is entrained in the liquid stream of water desorbing agent which flows upwardly through bed 12. This liquid mixture of the lactose component and the desorbing agent leave bed 12 through line 14 and a major portion thereof is withdrawn through line 16 and fed into evaporation apparatus 18 wherein the mixture is fractionated and the concentrated lactose is discharged through line 20 to be recycled to the isomerization reactor. The water desorbing agent leaves the evaporation apparatus 18 through line 22 and is fed to line 24 through which it is admixed with additional desorbing agent leaving the adsorbent bed 26, and is recycled to the bottom of adsorbent bed 30. The zeolite KSY or BaSY carrying adsorbed lactulose passes downward through line into bed 30 where it is counter-currently contacted with recycled desorbing agent which effectively desorbs the lactulose therefrom before the adsorbent passes through bed 30 and enters line 32 through which it is recycled to the top of adsorbent bed 26. The desorbing agent and desorbed lactulose leave 30 through line 34. A portion of this liquid mixture is diverted through line 36, where it passes evaporation apparatus 38, and the remaining portion passes upward through adsorbent bed 12 for further treatment as hereinbefore described. In evaporation apparatus 38, the desorbing agent and lactulose are fractionated. The lactulose product is recovered through line 40 and the desorbing agent is either disposed of or passes through line 42 into line 24 for recycle as described above. The undiverted portion of the desorbing agent/lactose mixture passes from bed 12 through line 14 enters bed 26 and moves counter-currently upward therethrough with respect to the desorbing agent laden zeolite adsorbent passing downwardly therethrough from recycle line 32. The desorbing agent passes from bed 26 in a relatively pure form through recycle line 24 and to bed 30 as hereinbefore described. The following examples are illustrative of the practice of this invention. However, they do not serve to limit the invention to the embodiments in the Examples. As used in the Examples appearing below the following abbreviations and symbols have the indicated meaning: BaY . . . barium-exchanged conventional zeolite Y BaSY . . . barium-exchanged steam-modified zeolite Y gpm/ft 2 . . . gallons per minute per square foot KSY . . . potassium-exchanged steam-modified zeolite Y EXAMPLE 1 A 1.6 meter column having an inside diameter of 0.77 cm was filled with 30×50 mesh barium-exchanged conventional zeolite Y bonded with 20% binder. The column was filled with water and flow rate through the column of 0.53 gpm/ft 2 was maintained. The column was held at a temperature of 160° F. For a period of two minutes a solution containing 5 weight percent lactose and 5 weight percent lactulose ("feed pulse") was substituted for the water stream and then the water stream containing no dissolved sugars was reestablished. The composition of the effluent stream from the column was determined by collecting samples and analyzing samples over time with a liquid chromatograph. The elution curves of the sugars are given in FIG. 1. At this flow rate, BaY cannot separate lactulose from lactose with efficiency. EXAMPLE 2 The same column and experimental procedures used in Example 1 were used. However, instead of using 30×50 mesh BaY, 30×50 mesh BaSY bonded with 20% binder was used. The elution curves given in FIG. 2 demonstrate that BaSY can efficiently separate lactulose from lactose. EXAMPLE 3 The same column and experimental procedures used in Example 1 were used. However, instead of using 30×50 mesh BaY, 30×50 mesh KSY bonded with 20% binder was used. The elution curves given in FIG. 3 indicate that KSY can also separate lactulose from lactose. EXAMPLE 4 The same column, experimental procedures and zeolite used in Example 3 were used. However, the feed pulse contained 5 weight % lactulose and 5% lactose. The elution curves are given in FIG. 4.

Lactulose is selectively adsorbed from admixture with lactose using specific cationic forms (particularly barium or potassium) of modified zeolite Y.

CROSS-REFERENCE TO RELATED APPLICATION This application is based upon and claims the benefit of priority of the prior Japanese Patent Application No. 2008-243237, filed on Sep. 22, 2008, the entire contents of which are incorporated herein by reference. FIELD The embodiments discussed herein are related to a housing in an electronic device and an electronic device having a housing in which a board is disposed. BACKGROUND Generally, as a method for joining walls of a housing of an electronic device such as a personal computer, there are known a method using screws and a method using claws protruding from one inner wall of a housing to be engaged in another wall (see, for example, Japanese Laid-open Patent Publications No. 05-315767 and No. 2000-59041). Meanwhile, a housing of an electronic device is required not only to have its walls firmly joined together thereby reliably preventing the separation of the walls, but also to avoid such an inconvenience that a wall of the housing is warped by receiving an external force like a press on the wall by a user. Further, as for a housing of an electronic device expected to reduce the size and weight, such as a notebook personal computer and a mobile telephone, disconnection of walls and deformation of a wall due to an external force need to be prevented efficiently in a limited space. SUMMARY According to an aspect of the invention, a housing includes: a pair of housing walls that face each other with an inner space therebetween; a first projection that projects from a first housing wall of the pair of housing walls toward a second housing wall of the pair of housing walls and abuts the second housing wall; and a second projection that projects from the second housing wall toward the first housing wall and engages in the first projection thereby preventing separation of the pair of housing walls. According to the housing described above, the first projection is formed to project from the first housing wall and abut the second housing wall to support the housing from inside, thereby preventing the second housing wall from warping due to an external force applied to the second housing wall. In addition, the second projection is formed to project from the second housing wall and engage in the first projection, thereby preventing the separation of the pair of housing walls. Further, since the second projection becomes integral with the first projection by engaging in the first projection, the space required to prevent the separation and the warp is made small. In other words, the housing described above makes it possible to efficiently prevent, in a tight space, the housing walls from being separated from each other and the wall being warped due to an external force. The object and advantages of the invention will be realized and attained by means of the elements and combinations particularly pointed out in the claims. It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory and are not restrictive of the invention, as claimed. BRIEF DESCRIPTION OF DRAWINGS FIG. 1 is an external view of a personal computer in a state (closed state) where a display unit is closed with respect to a main unit; FIG. 2 is an external view of the personal computer in a state (open state) where the display unit is opened with respect to the main unit; FIG. 3 is an external view of the personal computer in the closed state as illustrated in FIG. 1 , where the undersurface of the main unit is seen, with the display unit down; FIG. 4 illustrates a state where a dust filter illustrated in FIG. 3 is detached; FIG. 5 illustrates a state where a panel serving as the lower surface of the main unit illustrated in FIG. 4 is detached and thus an internal structure of the main unit is exposed; FIG. 6 illustrates a state where the dust filter is placed so as to have its filter main body inserted between a blowing opening of a fan and a heat radiating section; FIG. 7 is an enlarged view of the fan and the heat radiating section in a cooling unit illustrated in FIG. 5 ; FIG. 8 is an enlarged view of the dust filter; FIG. 9 illustrates a state where the dust filter and the fan are arranged; FIG. 10 illustrates a state where the dust filter and the heat radiating section are arranged; FIG. 11 illustrates a main unit of another embodiment in which the cooling unit in the main unit illustrated in FIG. 5 is replaced with another type of cooling unit which transfers heat to a heat radiating section by circulating a coolant; FIG. 12 illustrates a state where a dust filter is attached in the cooling unit illustrated in FIG. 11 ; FIG. 13 illustrates a side of the dust filter illustrated in FIG. 12 , which comes into contact with a blowing opening; FIG. 14 illustrates a state where a leaf spring of the dust filter is disposed at a position across the first and second pipes; FIG. 15 illustrates a state where three flat cables illustrated in FIG. 5 are connected to connectors mounted on the back side of the main board; FIG. 16 illustrates cable holding sections from the front side of the main board illustrated in FIG. 5 ; FIG. 17 illustrates the cable holding sections from a direction different from FIG. 16 on the front side of the main board illustrated in FIG. 5 ; FIG. 18 is an enlarged view of a sub-board illustrated in FIG. 5 ; FIG. 19 illustrates a state where the sub-board detached from the main board is turned over and connectors of the respective boards is seen; FIG. 20 is a side view illustrating how the sub-board connector and the main board connector are connected to each other; FIG. 21 illustrates a state where a TV signal cable illustrated in FIG. 5 is connected to an antenna module mounted on the back side of the sub-board; FIG. 22 illustrates the antenna module having the TV signal cable connected thereto; FIG. 23 is an enlarged view illustrating a cable holding section together with an output connector temporarily held by the cable holding section; FIG. 24 illustrates the display unit illustrated in FIG. 2 in a state of being detached from the main unit; FIG. 25 illustrates an upper panel removed from the display unit; FIG. 26 illustrates the display unit having the upper panel removed therefrom; FIG. 27 illustrates a state where locking claws arranged on a lower frame part, a liquid crystal side rib and a short rib are lined up; FIG. 28 is an enlarged view of an inverter circuit board in a housed state; FIG. 29 illustrates a state where a portion, covering an upper side of the inverter circuit board, in a retaining sheet covering the inverter circuit board is opened; FIG. 30 illustrates a state where the inverter circuit board is taken out of a concave section together with the retaining sheet; FIG. 31 illustrates a state where a single-lamp inverter circuit board also illustrated in FIG. 29 and the like and a double-lamp inverter circuit board are laid out; and FIG. 32 illustrates a state where the double-lamp inverter circuit board is housed in the concave section for housing the single-lamp inverter circuit board. DESCRIPTION OF EMBODIMENTS With reference to the drawings, description will be given below of a specific embodiment. An embodiment of an electronic device described below is a so-called notebook personal computer and has a structure in which a main unit and a display unit are connected to each other so as to be opened and closed. The main unit includes a keyboard and the like, and processes various kinds of information. The display unit displays images and the like. FIG. 1 is an external view of the personal computer in a state (closed state) where the display unit is closed with respect to the main unit. FIG. 2 is an external view of the personal computer in a state (open state) where the display unit is opened with respect to the main unit. This personal computer 10 includes a main unit 20 and a display unit 30 as described above. The main unit 20 and the display unit 30 are connected so that the display unit 30 is opened and closed in an arrow A direction with respect to the main unit 20 . The main unit 20 of the personal computer 10 has components such as a hard disk drive and various boards housed in a main-unit housing 21 . Further, the main unit 20 includes, on its upper surface, a keyboard 22 having multiple keys arranged thereon, a track pad 23 , a right-click button 24 and a left-click button 25 . The display unit 30 of the personal computer 10 displays results of information processing executed by the main unit 20 . The display unit 30 has a flat liquid crystal panel 32 , a control circuit for the liquid crystal panel 32 and the like housed in a display housing 31 . FIG. 3 is an external view of the personal computer in the closed state as illustrated in FIG. 1 , illustrating a state where the undersurface of the main unit is seen, with the display unit down. Note that FIG. 3 illustrates the rear of the personal computer 10 directed frontward in contrast to FIGS. 1 and 2 . The personal computer 10 of this embodiment, to be described later, uses a cooling unit for cooling with air various electronic components in the main unit 20 . As illustrated in FIG. 3 , the main unit 20 includes an inlet 26 on its lower surface. From the inlet 26 , cooling air is taken into the main unit 20 . The cooling unit allows the cooling air to absorb heat produced by the various electronic components so as to cool the various electronic components. As a result, the air thus warmed is discharged to the outside of the main unit 20 from an outlet 27 provided in the rear of the main unit 20 . Moreover, in this embodiment, a dust filter 131 for removing dust from the air used for cooling in the cooling unit is detachably attached to the main-unit housing 21 . FIG. 4 illustrates a state where the dust filter illustrated in FIG. 3 is detached. As illustrated in FIG. 4 , the dust filter 131 includes a filter main body 131 a having multiple ribs arranged in a lattice pattern. This filter main body 131 a removes dust from the air flowing toward the outlet 27 . The main-unit housing 21 has, in its lower surface, an opening 28 extended parallel to the outlet 27 . The dust filter 131 is inserted into the opening 28 . Meanwhile, the dust filter 131 has a leaf spring 131 b which biases the filter main body 131 a in a longitudinal direction indicated by an arrow B. When the dust filter 131 is inserted into the opening 28 , the leaf spring 131 b presses the filter main body 131 a against the main-unit housing 21 in the longitudinal direction indicated by the arrow B. The action by the leaf spring 131 b of pressing the filter main body 131 a fixes the dust filter 131 to the main-unit housing 21 . Moreover, a user may detach the dust filter 131 from the main-unit housing 21 by pushing the leaf spring 131 b with his/her finger and pulling the leaf spring 131 b out from the main-unit housing 21 . In this embodiment, the dust filter 131 may be easily detached from the main-unit housing 21 in this manner. Thus, the dust filter 131 may be cleaned as appropriate to avoid clogging of the dust filter 131 and the like. FIG. 5 illustrates a state where a panel serving as the lower surface of the main unit illustrated in FIG. 4 is detached and thus an internal structure of the main unit is exposed. Note that, in FIG. 5 , the display unit 30 and the dust filter 131 are also removed. As illustrated in FIG. 5 , the main unit 20 has a main board 110 , a sub-board 120 and the like housed therein. The main board 110 is a large-size board having various electronic components mounted thereon, such as a CPU 111 for performing overall control of the personal computer 10 and chipsets 112 for controlling data communication and the like in the CPU 111 and the like. The sub-board 120 is connected to the main board 110 through a connector and has an antenna module to be described later and the like mounted thereon. The CPU 111 and the chipsets 112 mounted on the main board 110 produce heat while executing signal processing. Therefore, those components are preferably constantly cooled during operations of the personal computer 10 in order to avoid malfunction or the like due to the heat thus produced. In this embodiment, for cooling the CPU 111 and the chipsets 112 , a cooling unit 130 to be described below is mounted on the main unit 20 . The cooling unit 130 includes a heat transfer section 132 having a heat absorbing plate 132 a made of copper. The heat absorbing plate 132 a comes into contact with the CPU 111 and the two chipsets 112 to absorb heat produced by those components. The heat transfer section 132 also has a heat pipe 132 b for transferring the heat absorbed by the heat absorbing plate 132 a to a heat radiating section 133 to be described later. In the cooling unit 130 , the heat transfer section 132 brings the heat produced by the CPU 111 and the two chipsets 112 into the heat radiating section 133 . The heat radiating section 133 has a structure in which metal fins 133 a are arranged at predetermined intervals in a ventilator through which the air passes. Here, the ventilator defines a ventilation area. The heat transferred to the heat radiating section 133 by the heat transfer section 132 comes to the fins 133 a included in the heat radiating section 133 . The cooling unit 130 further includes a fan 134 for blowing air in a direction indicated by an arrow C so as to allow the air to flow between the fins 133 a in the heat radiating section 133 . The air blown by the fan 134 passes between the fins 133 a so that the heat coming to the fins 133 a is radiated into the air. The air warmed by the heat radiation is discharged from the outlet 27 illustrated in FIGS. 3 and 4 . In this event, if some of the air blown over the heat radiating section 133 leaks to the surrounding without passing between the fins 133 a , cooling efficiency of the fins 133 a is lowered. This lowered cooling efficiency of the fins 133 a eventually causes a decrease in efficiency of cooling the CPU 111 and the chipsets 112 . Here, in this embodiment, the dust filter 131 illustrated in FIGS. 3 and 4 is disposed such that the filter main body 131 a is inserted through the opening 28 illustrated in FIG. 4 to be placed between the heat radiating section 133 and a blowing opening 134 a . The blowing opening 134 a is directed toward the heat radiating section 133 so that the air pushed by the fan 134 comes out through the blowing opening 134 a. FIG. 6 illustrates a state where the dust filter is placed so as to have the filter main body inserted between the blowing opening of the fan and the heat radiating section. The filter main body 131 a of the dust filter 131 removes dust from the air blown toward the heat radiating section 133 by the fan 134 . Thus, clogging between the fins 133 a in the heat radiating section 133 or the like is avoided. However, the filter main body 131 a resists the air blown toward the heat radiating section 133 . Therefore, some of the air hitting the filter main body 131 a tends to veer off the direction heading toward the heat radiating section 133 . Here, in this embodiment, the filter main body 131 a of the dust filter 131 also serves as a part of a duct wall which surely guides the air from the fan 134 to the spaces between the fins 133 a included in the heat radiating section 133 while preventing air leaks to the surrounding. Meanwhile, a wall surface or the like of the main-unit housing 21 forms a different portion of the duct wall, which also helps forcibly guide the air that tends to veer toward the heat radiating section 133 . Thus, a decrease in cooling efficiency is prevented. Moreover, this embodiment employs a commercially available fan as the fan 134 included in the cooling unit 130 and commercially available radiating fins as the heat radiating section 133 , so that a cost reduction is achieved. However, this has resulted in the differences in size and position between the blowing opening 134 a in the fan 134 and the heat radiating section 133 , which will be described below. FIG. 7 is an enlarged view of the fan and the heat radiating section in the cooling unit illustrated in FIG. 5 . As illustrated in FIG. 7 , in this embodiment, a width d 1 of the blowing opening 134 a is smaller than a width d 2 of the heat radiating section 133 . Moreover, the position of the right side surface of the blowing opening 134 a is shifted from the position of the right side surface of the heat radiating section 133 . Furthermore, the position of the left side surface of the blowing opening 134 a is also shifted from the position of the left side surface of the heat radiating section 133 . Therefore, in this embodiment, in order to allow the filter main body 131 a of the dust filter 131 to serve as a part of the duct wall, a shape of the dust filter 131 is designed as described below to guide the air blown out of the blowing opening 134 a to the spaces between the fins 133 a included in the heat radiating section 133 . FIG. 8 is an enlarged view of the dust filter. FIG. 8 illustrates the dust filter 131 with a side to contact the blowing opening 134 a facing upward and a side to contact the heat radiating section 133 facing downward. In this embodiment, the filter main body 131 a of the dust filter 131 includes two shielding ribs, a shielding rib 131 c on the fan side and a shielding rib 131 d on the heat radiating section side, as shielding ribs for preventing the air blown out of the blowing opening 134 a from leaking laterally. The shielding rib 131 c protrudes along the side surface of the fan 134 toward the fan 134 from the side of the filter main body 131 a that comes into contact with the blowing opening 134 a . The shielding rib 131 c is provided at a position corresponding to the width d 1 of the blowing opening 134 a illustrated in FIG. 7 . Moreover, the shielding rib 131 d protrudes along the side surface of the heat radiating section 133 toward the heat radiating section 133 from the side of the filter main body 131 a coming into contact with the heat radiating section 133 . The shielding rib 131 d is provided at a position corresponding to the width d 2 of the heat radiating section 133 illustrated in FIG. 7 . FIG. 9 illustrates a state where the dust filter and the fan are arranged. FIG. 10 illustrates a state where the dust filter and the heat radiating section are arranged. As illustrated in FIG. 9 , the shielding rib 131 c is provided at a position slightly outside the edge of the blowing opening 134 a . As a result, the filter main body 131 a of the dust filter 131 is provided with an air inlet of a size and a position corresponding to those of the blowing opening 134 a of the fan 134 so that the air blown out of the blowing opening 134 a is taken into the filter main body 131 a without any leak. Moreover, as illustrated in FIG. 10 , the shielding rib 131 d is provided at a position slightly outside the edge of the heat radiating section 133 . Furthermore, a blocking plate 131 e is provided between the shielding rib 131 c and the shielding rib 131 d . Thus, as illustrated in FIG. 10 , the air passing near the shielding rib 131 c flows in a direction indicated by an arrow D and heads toward the heat radiating section 133 without leaking. In this structure, the filter main body 131 a of the dust filter 131 is provided with an air outlet of a size and a position corresponding to those of a portion of the heat radiating section 133 onto which the air is blown, so that the air taken into the filter main body 131 a flows toward the heat radiating section 133 . As described above with reference to FIGS. 6 to 10 , in the cooling unit 130 of this embodiment, the filter main body 131 a of the dust filter 131 has the air inlet of the size and the position corresponding to those of the blowing opening 134 a of the fan 134 and the air outlet of the size and the position corresponding to those of the portion of the heat radiating section 133 onto which the air is blown. Thus, the filter main body 131 a serves as a part of the wall of the duct which takes in the air blown out of the blowing opening 134 a without any leak and guides the air to the heat radiating section 133 . As a result, the CPU 111 and the chipsets 112 illustrated in FIG. 5 are efficiently cooled. Note that, there has been described the cooling unit 130 , illustrated in FIG. 5 , of the type using the heat pipe 132 b to transfer the heat to the heat radiating section, as an example of the cooling unit for cooling the CPU 111 and the chipsets 112 . However, the cooling unit for cooling the CPU 111 and the chipsets 112 is not limited to this type of cooling unit but may be of a different type which transfers the heat to the heat radiating section by circulating a coolant. This different type of cooling unit will be described below. Note that this different type of cooling unit will be hereinafter called a second cooling unit. FIG. 11 illustrates a main unit of another embodiment in which the cooling unit in the main unit illustrated in FIG. 5 is replaced with a second cooling unit which transfers heat to a heat radiating section by circulating a coolant. A main unit 20 ′ of the another embodiment illustrated in FIG. 11 has a second cooling unit 510 mounted thereon, which transfers heat to a heat radiating section by circulating a coolant, the second cooling unit being of a type different from that of the cooling unit 130 illustrated in FIG. 5 . The second cooling unit 510 includes one CPU heat absorbing section 511 and two chipset heat absorbing sections 512 , which are metal heat absorbing sections in which the coolant flows. Specifically, the CPU heat absorbing section 511 absorbs heat produced by a CPU 111 , and the chipset heat absorbing sections 512 absorb heat produced by two chipsets 112 , respectively. In the second cooling unit 510 , the above three heat absorbing sections are connected to each other. Inside the connected body, provided are partition walls 513 forming, together with pipes to be described later, a passage indicated by arrows in FIG. 11 that guides the coolant to flow out of a heat radiating section 515 and back to the heat radiating section 515 . Moreover, the second cooling unit 510 also includes a fan 514 equivalent to the fan 134 illustrated in FIG. 5 and further includes the heat radiating section 515 having metal fins arranged in a blowing opening through which air from the fan 514 passes. Moreover, the heat radiating section 515 also includes a liquid passage through which the coolant flows, and the fins come into contact with the liquid passage. The air passing between the fins discharges heat of the coolant in the liquid passage. The heat radiating section 515 is connected to the chipset heat absorbing section 512 through a first pipe 516 guiding the coolant from the heat radiating section 515 elsewhere. Moreover, the heat radiating section 515 is connected to the CPU heat absorbing section 511 through a second pipe 517 guiding the coolant to the heat radiating section 515 . Moreover, the second cooling unit 510 includes a pump 518 for circulating the coolant. Thus, in the second cooling unit 510 , a circulating passage is formed, which allows the coolant to flow out of the heat radiating section 515 , through the two chipset heat absorbing sections 512 , the pump 518 and the CPU heat absorbing section 511 in this order, and then to come back to the heat radiating section 515 . Here, among the CPU 111 and the two chipsets 112 , the CPU 111 is a maximum heat-producing element having a maximum heating value. In general, a conventional type of cooling unit, which transfers heat to a heat radiating section by circulating a coolant, often allows the coolant in a lowest temperature state, which has just left the heat radiating section, preferentially to flow to a maximum heat absorbing section which absorbs heat produced by the maximum heat-producing element such as the CPU. Meanwhile, from the viewpoint of heat resistance, many pumps used for circulating such a coolant have an upper limit set for a temperature of the coolant that flows therethrough. When the coolant preferentially flows to the maximum heat absorbing section as described above, the temperature of the coolant is likely to exceed the upper temperature limit in the pump. Thus, many conventional units require a complex passage, in which the coolant, after flowing out of the heat radiating section, goes to the maximum heat absorbing section thereby having the temperature increased, and then comes back to the heat radiating section again for radiating heat, and finally arrives at the pump. In contrast, in the second cooling unit 510 illustrated in FIG. 11 , the coolant that has just left the heat radiating section 515 preferentially flows to the chipset heat absorbing sections 512 absorbing the heat of the chipsets 112 having a heating value smaller than that of the CPU 111 . In the second cooling unit 510 , the chipset heat absorbing sections 512 serve as minimum heat absorbing sections having a heat absorption amount smaller than that of the CPU heat absorbing section 511 that is a maximum heat absorbing section. Moreover, in the second cooling unit 510 , the coolant that has left the chipset heat absorbing sections 512 as the minimum heat absorbing sections is sent to the CPU heat absorbing section 511 as the maximum heat absorbing section through the pump 518 . In the development of the second cooling unit 510 , the following has been confirmed. Specifically, an increase in the temperature of the coolant due to the heat produced by the chipsets 112 does not exceed the upper temperature limit in the pump 518 . Furthermore, even the coolant having the temperature somewhat increased by the heat produced by the chipsets 112 sufficiently endures a transfer of heat produced by the CPU 111 and absorbed by the CPU heat absorbing section 511 . The second cooling unit 510 cools the CPU 111 and the chipsets 112 with a shortest passage, unlike a conventional complex passage, by circulating the coolant in the above order. Therefore, the second cooling unit 510 is efficiently placed in a limited space within the electronic device and thus cools the electronic device. Meanwhile, in the second cooling unit 510 , both of the two chipset heat absorbing sections 512 as the minimum heat absorbing sections are arranged on the upstream side of the pump 518 . Although the pump 518 generates some heat, the above arrangement of the two chipset heat absorbing sections 512 in the second cooling unit 510 makes it possible to cool both of the two chipsets 112 while avoiding the influence of the heat produced by the pump 518 . Thus, the second cooling unit 510 realizes further efficient cooling. Moreover, in the second cooling unit 510 , the heat of the coolant inside the heat radiating section 515 is radiated by the air from the fan 514 . Thus, compared with, for example, heat radiation by natural convection, further efficient heat radiation is performed. Note that, here, the description has been given of the structure in which all of the heat absorbing sections for the two chipsets are arranged on the upstream side of the pump in the flow of the coolant as an example of the cooling unit of the type which transfers the heat to the heat radiating section by circulating the coolant. However, the cooling unit of the type which transfers the heat to the heat radiating section by circulating the coolant is not limited thereto but at least one of the heat absorbing sections for the chipsets may be arranged on the upstream side of the pump. Here, the second cooling unit 510 also includes a dust filter having a filter main body for removing dust from air flowing toward the heat radiating section 515 from the fan 514 and serving as a part of a duct wall for blowing air from the fan 514 onto the heat radiating section 515 without any leak. Note that FIG. 11 illustrates a state where the dust filter is removed. FIG. 12 illustrates a state where the dust filter is attached in the second cooling unit illustrated in FIG. 11 . As illustrated in FIG. 12 , also in the second cooling unit 510 , there is provided a dust filter 519 having a filter main body 519 a inserted between a blowing opening 514 a of the fan 514 and the heat radiating section 515 . Here, in the second cooling unit 510 , a width of the blowing opening 514 a (see FIG. 11 ) and a width of the heat radiating section 515 are approximately equal to each other. Moreover, positions, in a width direction, of the blowing opening 514 a and the heat radiating section 515 approximately agree with each other. Meanwhile, as illustrated in FIG. 12 , there is a difference between a height h 1 of the blowing opening 514 a and a height h 2 of the heat radiating section 515 . Furthermore, positions of the blowing opening 514 a and the heat radiating section 515 are shifted from each other in a height direction. Here, in the second cooling unit 510 , the shape of the filter main body 519 a of the dust filter 519 is designed as described below to deal with the differences in height and position. In this embodiment, first, in the filter main body 519 a of the dust filter 519 , a shielding rib 519 b for preventing the air coming out of the blowing opening 514 a from leaking in the height direction is provided on the blowing opening 514 a side having a relatively low height in the filter main body 519 a of the dust filter 519 . FIG. 13 illustrates a side of the dust filter illustrated in FIG. 12 , which comes into contact with the blowing opening. As illustrated in FIG. 13 , the shielding rib 519 b is a canopy-shaped rib protruding along an upper surface of the fan 514 toward the fan 514 from the side of the filter main body 519 a coming into contact with the blowing opening 514 a . This shielding rib 519 b is provided at a position in the filter main body 519 a , the position corresponding to the height h 1 (see FIG. 12 ) of the blowing opening 514 a. Moreover, in this embodiment, as illustrated in FIG. 12 , an upper surface 519 c of the dust filter 519 is provided at a position corresponding to the relatively high height h 2 of the heat radiating section 515 . Furthermore, an edge of the upper surface 519 c on the heat radiating section 515 side protrudes toward the heat radiating section 515 to be in a canopy shape along an upper surface of the heat radiating section 515 . Furthermore, as indicated by a dotted line in FIG. 12 , a blocking plate 519 d is provided to block a space between the shielding rib 519 b and the upper surface 519 c on the fan 514 side. Moreover, a passage of the air passing through the filter main body 519 a extends from the fan 514 side toward the heat radiating section 515 as indicated by a dotted line in FIG. 12 . Moreover, the shape of a lower surface opposed to the upper surface 519 c in the dust filter 519 spreads toward a lower surface of the heat radiating section 515 from a lower surface of the blowing opening 514 a . This structure allows formation of an air inlet and an air outlet in the dust filter 519 , a size and a position of the air inlet corresponding to those of the blowing opening 514 a of the fan 514 and a size and a position of the air outlet corresponding to those of a portion of the heat radiating section 515 onto which the air is blown. Thus, the air coming from the fan 514 heads toward the heat radiating section 515 without leaking. Moreover, as in the case of the dust filter 131 illustrated in FIG. 4 and the like, the dust filter 519 also has a leaf spring 519 e provided as illustrated in FIGS. 12 and 13 , the leaf spring being intended to fix the dust filter 519 with a pressing operation of the filter main body 519 a against the housing. In order to effectively press the filter main body 519 a against the housing, the leaf spring 519 e is preferably disposed as close to the filter main body 519 a as possible. Incidentally, in the second cooling unit 510 illustrated in FIGS. 11 to 13 , the first and second pipes 516 and 517 are connected to the heat radiating section 515 . These pipes are arranged just proximal to the heat radiating section 515 along the flow of the air. Thus, if the leaf spring 519 e of the dust filter 519 is disposed near the filter main body 519 a as described above, the leaf spring 519 e interferes with the first and second pipes 516 and 517 . On the other hand, when the pipes are detoured and arranged to dispose the leaf spring 519 e at the desirable position, the circulation route of the coolant devised as described with reference to FIG. 11 has to be extended. Such a detour lowers cooling efficiency of the second cooling unit 510 . Therefore, the second cooling unit 510 is configured so that, in attachment of the dust filter 519 , the leaf spring 519 e of the dust filter 519 is disposed at a position across the first and second pipes 516 and 517 arranged just proximal to the heat radiating section 515 . FIG. 14 illustrates a state where the leaf spring of the dust filter is disposed at a position across the first and second pipes. As illustrated in FIG. 14 , in the second cooling unit 510 , the leaf spring 519 e of the dust filter 519 is disposed at a position slightly distant from the filter main body 519 a. Thus, in attachment of the dust filter 519 , the leaf spring 519 e is disposed at a position across the first and second pipes 516 and 517 arranged just proximal to the heat radiating section 515 . In the second cooling unit 510 , such arrangement of the leaf spring 519 e enables the first and second pipes 516 and 517 to be arranged just proximal to the heat radiating section 515 , thereby preventing a decrease in cooling efficiency. Note that the description has been given of the dust filter 519 of a type having the leaf spring disposed to avoid the pipes passing near the heat radiating section as an example of the dust filter including the filter main body and the leaf spring. However, the dust filter having the leaf spring disposed to avoid the components near the heat radiating section is not limited to this example. For instance, the dust filter may be a type having the leaf spring disposed to avoid electronic components and the like near the heat radiating section. This concludes the description of the another embodiment including the second cooling unit 510 with reference to FIGS. 11 to 14 . Referring back to FIG. 5 again, an internal structure of the main unit 20 of the personal computer 10 illustrated in FIG. 5 will be described. In the main unit 20 , various input signals generated using the keyboard 22 , the track pad 23 and the right and left click buttons 24 and 25 illustrated in FIG. 2 by the user operating the respective parts are sent to the main board 110 . In this embodiment, three flat cables 140 are used to transmit the various input signals to the main board 110 . The three flat cables 140 each have one end connected to a connector mounted on a back side of the main board 110 through a path which is partially along an inner wall of the main-unit housing 21 , the back side of the main board 110 being opposed to the side having the CPU 111 and the cooling unit 130 mounted thereon. FIG. 15 illustrates a state where the three flat cables illustrated in FIG. 5 are connected to the connectors mounted on the back side of the main board. FIG. 15 illustrates an enlarged view of a portion where the back side of the main board 110 is exposed from the main-unit housing 21 in a state where the keyboard 22 is detached from the main unit 20 illustrated in FIG. 2 . As illustrated in FIG. 15 , on the back side of the main board 110 , three flat cable connectors 113 are mounted so as to correspond to the three flat cables 140 , respectively. The flat cables 140 are connected to the flat cable connectors 113 , respectively. Here, in order to connect the flat cables 140 to the flat cable connectors 113 , respectively, in assembly of the main unit 20 , leading ends of the flat cables 140 have to be moved in a direction of connection to the flat cable connectors 113 indicated by arrows E in FIG. 15 , in other words, in longitudinal directions of the flat cables 140 . Conventionally, above operations are often performed by positioning the flat cables by temporarily fixing the flat cables to the housing or the like with tapes and then connecting the flat cables to the connectors by moving the leading ends of the flat cables in the longitudinal directions. Such a method requires some margins in length between the temporary fixing positions and the leading ends for allowing an operator to perform the operation by moving the leading ends. As a result, the lengths of the connected flat cables turn out to be redundant. Accordingly, there arises a problem that such redundancies hinder the assembly operation of the electronic device after connection of the flat cables and thus workability is lowered. Therefore, in this embodiment, flat cable holding sections 21 a for holding the flat cables 140 while allowing the flat cables 140 to be movable in the longitudinal directions are provided on the paths before reaching the flat cable connectors 113 , respectively. FIG. 16 illustrates the cable holding sections from the front side of the main board illustrated in FIG. 5 . FIG. 17 illustrates the cable holding sections from a direction different from FIG. 16 on the front side of the main board illustrated in FIG. 5 . The flat cable holding sections 21 a are provided for the flat cables 140 respectively. The flat cable holding section 21 a has a band-shaped structure, which protrudes higher than a thickness of the flat cable 140 from the inner wall of the main-unit housing 21 , is bent in a direction along the inner wall, and extends longer than a width of the flat cable 140 along the inner wall. Each of the flat cables 140 extends toward the main board 110 from the front side of the main board 110 and reaches the back side of the main board 110 by passing under the extended portion of each of the flat cable holding sections 21 a . In this way, the flat cable 140 is connected to each of the flat cable connectors 113 as illustrated in FIG. 15 . Such a structure enables the flat cables 140 to be held by the flat cable holding sections 21 a while being movable in the longitudinal directions when the flat cables 140 are to be connected to the flat cable connectors 113 . Thus, margins for moving the leading ends as in the conventional case are not particularly required to be prepared. Accordingly, the flat cables 140 is shortened and thus the workability is improved. Moreover, in this embodiment, the main board 110 is attached to the inner wall of the main-unit housing 21 . The flat cables 140 are connected to the flat cable connectors 113 mounted on the back side of the main board 110 , that is, the inner wall side of the main board 110 . With this structure, in the processing of connecting the flat cables 140 , the main-unit housing 21 , which is in a state of having the main board 110 attached thereto and having the flat cables 140 laid to some extent, needs to be turned over at least once. In this embodiment, during turning over the main-unit housing 21 , the flat cables 140 are held by the above flat cable holding sections 21 a . Thus, the main-unit housing 21 may be turned over while maintaining the positions of the arranged flat cables 140 . In this regard as well, the workability is improved. Moreover, as described above, in this embodiment, each of the flat cable holding sections 21 a is provided for each of the flat cables 140 . Thus, the positions of the flat cables 140 are surely maintained for each of the flat cables 140 as described above. Note that the description has been given here of the flat cable holding sections 21 a holding the flat cables as an example of the cable holding sections for holding the cables so that the cables are movable along the arrangement paths as described above. However, such cable holding sections are not limited to the use in holding the flat cables but also may be applied to hold general cables. This concludes the description of the flat cables 140 with reference to FIGS. 15 to 17 . Referring back to FIG. 5 again, description of the internal structure of the main unit 20 of the personal computer 10 of this embodiment will be continued. As described above, the main unit 20 has the main board 110 and the sub-board 120 housed therein, the sub-board being connected to the main board 110 through a connector and including an antenna module to be described later and the like mounted thereon. Here, in this embodiment, the sub-board 120 is fixed to the main board 110 and the main-unit housing 21 with screws. Thus, through-holes through which the screws for fixing those described above penetrate are provided in the sub-board 120 . FIG. 18 is an enlarged view of the sub-board illustrated in FIG. 5 . As illustrated in FIG. 18 , in the sub-board 120 , provided are: two through-holes (main board through-holes) 121 for screwing the sub-board 120 to the main board 110 ; and four through-holes (housing through-holes) 122 for screwing the sub-board 120 to the main-unit housing 21 . Moreover, in this embodiment, the two main board through-holes 121 are circular holes and the four housing through-holes 122 are elongate holes. This is because the sub-board 120 and the main board 110 are connected to each other through connectors as described below. FIG. 19 illustrates a state where the sub-board detached from the main board is turned over and the connectors of the respective boards is seen. FIG. 20 is a side view illustrating how the sub-board connector and the main board connector are connected to each other. Note that FIGS. 19 and 20 illustrate a state where the antenna module to be described later is detached from the sub-board. As illustrated in FIG. 19 , the sub-board 120 includes a rectangular male connector 123 for connection to the main board 110 on a back side opposed to the side illustrated in FIG. 18 . Meanwhile, the main board 110 includes on its front side a rectangular female connector 114 to be engaged with the male connector 123 . These two board connectors are connected to each other as illustrated in FIG. 20 in assembly of the main unit 20 . Here, the male connector 123 is attached to the sub-board 120 , and the female connector 114 is attached to the main board 110 by soldering the connectors to the boards, respectively. Thus, a position on the sub-board 120 to which the male connector 123 is attached, and a position on the main board 110 to which the female connector 114 is attached may be erroneously shifted in a rotational direction from their respective attachment positions in design. When there are such shifts in the rotational direction in the attachment positions of the male connector 123 and the female connector 114 , the sub-board 120 is shifted in a circumferential direction indicated by an arrow F around the male connector 123 as illustrated in FIG. 18 . As a result, between each of the six through-holes provided in the sub-board 120 and each of screw holes corresponding thereto, there occur positional shifts around the male connector 123 in a direction corresponding to the circumference according to a distance from the center. Among the six through-holes, the two main board through-holes 121 are provided near the male connector 123 , and thus, such positional shifts are small. However, the four housing through-holes 122 provided at positions distant from the male connector 123 may have large positional shifts. Therefore, in this embodiment, in order to cope with such positional shifts, the four housing through-holes 122 are formed to be the elongate holes extending in the direction of a tangent to the circumference passing through the screw attachment positions around the male connector 123 . Thus, even if there are such shifts of the attachment positions of the male connector 123 and the female connector 114 , the sub-board 120 is easily screwed to the main-unit housing 21 . Note that, in consideration of a manufacturing workability, this embodiment provides the description in which the direction of the tangent to the circumference passing through the screw attachment positions is used as an example of a direction having a predetermined relationship with the circumference. Moreover, the housing through-holes 122 are formed as elongate holes linearly extended in the direction of the tangent to the circumference passing through the screw attachment positions. However, the direction having the predetermined relationship with the circumference passing through the screw attachment positions may be a direction along the circumference. Moreover, the housing through-holes 122 may be circular elongate holes along the circumference. Moreover, here, the screws have been described as an example of fastening members for fixing the sub-board 120 to the main board 110 and the main-unit housing 21 as described above. However, the fastening members are not limited to the screws but may be other kinds of fastening members such as press-fit pins. This concludes the description of screwing the sub-board 120 with reference to FIGS. 18 to 20 . Referring back to FIG. 5 again, description of the internal structure of the main unit 20 of the personal computer 10 of this embodiment will be continued. In this embodiment, the main unit 20 includes a TV signal connector 150 capable of receiving a TV antenna signal. Moreover, a TV signal cable 160 extending from the TV signal connector 150 to transmit the TV antenna signal is connected to the antenna module to be described later which is mounted on the back side of the sub-board 120 . FIG. 21 illustrates a state where the TV signal cable illustrated in FIG. 5 is connected to the antenna module mounted on the back side of the sub-board. FIG. 22 illustrates the antenna module having the TV signal cable connected thereto. An antenna module 170 is a board for converting the TV antenna signal into a signal that may be handled within the personal computer 10 by performing signal processing compliant with predetermined communication standards, the TV antenna signal received by the TV signal connector 150 and transmitted through the TV signal cable 160 . This antenna module 170 is mounted on the back side of the sub-board 120 . Moreover, on the antenna module 170 , a connector (input connector) 171 for inputting a TV signal to the antenna module 170 is mounted. Furthermore, the TV signal cable 160 includes a TV signal output connector 161 at its leading end on the antenna module 170 side, the TV signal output connector 161 being connected to the TV signal input connector 171 . Here, FIG. 22 illustrates an enlarged view of a portion where the antenna module 170 is exposed from the main-unit housing 21 in a state where the keyboard 22 is detached from the main unit 20 illustrated in FIG. 2 . As illustrated in FIG. 22 , the main-unit housing 21 includes an operation opening 21 b for the operator to access the TV signal input connector 171 of the antenna module 170 in assembly of the main unit 20 . The TV signal output connector 161 of the TV signal cable 160 is connected to the TV signal input connector 171 of the antenna module 170 with an operation through the operation opening 21 b in the main-unit housing 21 . Here, generally, the above TV signal connector is often attached to the back side of the main unit of the personal computer as in the case of this embodiment illustrated in FIG. 5 . On the other hand, the antenna module may be disposed at a position near the front side opposed to the back side, as in the case of this embodiment illustrated in FIG. 5 , as a matter of arrangement convenience inside the main unit. In this case, the output connector of the TV signal cable is connected to the input connector of the antenna module in the following manner. First, as illustrated in FIG. 5 , the lower surface of the main unit is turned up and the TV signal cable is arranged so as to allow the output connector to come close to the antenna module. Thereafter, the main unit is turned over and the output connector is connected to the input connector with an operation through the operation opening for the access to the antenna module on the upper surface of the main unit. Conventionally, during such an operation, operational inefficiency often occurs in that the TV signal cable has to be rearranged, since the output connector of the TV signal cable retracts into the housing when the main unit is turned over. To avoid such operational inefficiency, in the main unit 20 of this embodiment, the TV signal output connector 161 may be temporarily held when the TV signal cable 160 is arranged as described above. For this purpose, a TV signal cable holding section 21 c is provided on the lower surface illustrated in FIGS. 5 and 21 in the main-unit housing 21 . Specifically, the TV signal cable holding section 21 c holds the TV signal cable 160 so as to allow a part (that is an end or a middle part) of the TV signal cable 160 to reach the operation opening 21 b. FIG. 23 is an enlarged view illustrating the cable holding section together with the output connector temporarily held by the cable holding section. The TV signal cable holding section 21 c has a slit formed therein, the slit having a width smaller than the size of the TV signal output connector 161 . Once the TV signal cable 160 is arranged as described above, a cable main body 162 is inserted into the slit as illustrated in FIG. 23 . As mentioned above, the slit in the TV signal cable holding section 21 c has the width smaller than the size of the TV signal output connector 161 . Therefore, even when the main unit 20 is turned over to connect the TV signal output connector 161 to the TV signal input connector 171 of the antenna module 170 , the TV signal output connector 161 remains being held by the TV signal cable holding section 21 c . Accordingly, it is possible to avoid such an operational inefficiency that the TV signal output connector 161 retracts into the main-unit housing 21 during the operation. In this embodiment, the workability is improved by such an action of the TV signal cable holding section 21 c. Moreover, in this embodiment, the antenna module 170 has the TV signal input connector 171 on the side facing the operation opening 21 b . Thus, the connectors are allowed to be connected through the operation opening 21 b . In this regard as well, the workability is improved. Moreover, in this embodiment, the TV signal cable holding section 21 c is provided on the arrangement path of the TV signal cable 160 and on the edge of the operation opening 21 b . Thus, the operation of connecting the connectors through the operation opening 21 b is facilitated. Thus, the workability is further improved. Note that, here, the description has been given of the TV signal cable 160 and the antenna module as examples of the cable and the board, which are connected to each other by engaging the connectors thereof with each other. However, the cable and the board are not limited thereto and a radio communication cable and a radio module, for example, may be used. This concludes the description of the internal structure of the main unit 20 with reference to FIGS. 5 to 23 . Next, the display unit 30 illustrated in FIG. 2 will be described. FIG. 24 illustrates the display unit illustrated in FIG. 2 in a state of being detached from the main unit. As described above, the display unit 30 has the flat liquid crystal panel 32 , the control circuit for the liquid crystal panel and the like housed in the display housing 31 . Moreover, the display housing 31 includes an upper panel 311 and a lower panel 312 . The upper panel 311 is a housing wall forming a frame of an opening through which a display screen of the liquid crystal panel 32 is exposed. The lower panel 312 is a housing wall facing the upper panel 311 with an internal space therebetween. In the internal space, the liquid crystal panel 32 and the like are housed. Electronic components to be housed in the display unit 30 , such as the liquid crystal panel 32 , are fixed to the lower panel 312 . FIG. 25 illustrates the upper panel removed from the display unit. FIG. 26 illustrates the display unit having the upper panel removed therefrom. FIG. 25 illustrates the upper panel 311 in a reversed state. Moreover, FIG. 25 illustrates a connection side of the main unit 20 and the display unit 30 positioned frontward. FIG. 26 illustrates the liquid crystal panel 32 fixed to the lower panel 312 , an inverter circuit board 33 for turning on a backlight of the liquid crystal panel 32 , and the like. Moreover, in the lower panel 312 , a concave section 313 for housing the inverter circuit board 33 is provided, the concave section 313 being formed of ribs surrounding its periphery. The inverter circuit board 33 is housed in the concave section 313 in a state of being covered with a retaining sheet 34 for retaining the inverter circuit board 33 in the concave section 313 . Specifically, the retaining sheet 34 is formed of a PET film and details thereof will be described later. In this embodiment, the upper panel 311 is fixed to the lower panel 312 by use of screws or by locking with locking claws provided on an outer edge of the upper panel 311 . Here, a lower frame part 311 a of the upper panel 311 on the connection side is wider than an upper frame part 311 b opposed to the connection side or two side frame parts 311 c. Thus, in the lower frame part 311 a , a space is easily formed between the liquid crystal panel 32 and an inner edge of the lower frame part 311 a. Therefore, in this embodiment, four locking claws 311 d for preventing the lower frame part 311 a and the lower panel 312 from separating from each other by fixing the inner edge of the lower frame part 311 a to the lower panel 312 are arranged near the inner edge so as to align along the edge of the liquid crystal panel 32 in a state where the upper panel 311 is assembled to the lower panel 312 . The four locking claws 311 d are protrusions protruding toward the lower panel 312 from the lower frame part 311 a . The locking claws 311 d catch on a rib (liquid crystal side rib) 313 a on the liquid crystal panel 32 side among the ribs forming the concave section 313 illustrated in FIG. 26 and a short rib 314 arranged to the right, in FIG. 26 , of the liquid crystal side rib 313 a with a wiring space left therebetween. FIG. 27 illustrates a state where the locking claws 311 d arranged on the lower frame part, the liquid crystal side rib 313 a and the short rib 314 are lined up. As illustrated in FIG. 27 , the liquid crystal side rib 313 a has three locking holes 313 a _ 1 provided therein and the short rib 314 has one locking hole 314 a provided therein. Among the four locking claws 311 d , the three locking claws 311 d on the left side in FIG. 27 catch on the three locking holes 313 a _ 1 in the liquid crystal side rib 313 a , respectively. Moreover, among the four locking claws 311 d , the one locking claws 311 d on the right side in FIG. 27 catches on the locking hole 314 a in the short rib 314 . When the four locking claws 311 d catch on the three locking holes 313 a _ 1 in the liquid crystal side rib 313 a and the one locking hole 314 a in the short rib 314 , respectively, the inner edge of the lower frame part 311 a is fixed to the lower panel 312 . Thus, the liquid crystal panel 32 and the inner edge of the lower frame part 311 a are prevented from being spaced apart from each other. Moreover, since the lower frame part 311 a is wide as described above, the lower frame part 311 a is easily bent when pressed by the user or the like. Therefore, in this embodiment, the liquid crystal side rib 313 a and the short rib 314 are formed so as to have their upper edges come into contact with the lower frame part 311 a of the upper panel 311 in a state where the upper panel 311 is attached to the lower panel 312 . Thus, the liquid crystal side rib 313 a and the short rib 314 react to the pressure applied to the lower frame part 311 a , thereby preventing the lower frame part 311 a from bending. Here, in this embodiment, as described above, in the state where the upper panel 311 is attached to the lower panel 312 , the locking claws 311 d , for preventing the liquid crystal panel 32 and the inner edge of the lower frame part 311 a from being spaced apart from each other, and the ribs 313 a and 314 for preventing the lower frame part 311 a from bending are integrated with each other. Thus, in this embodiment, the spacing and bending are efficiently prevented within a limited space. Note that, here, the description has been given of the structure in which the four locking claws 311 d are provided as protrusions protruding toward the lower panel 312 from the upper panel 311 and the two types of ribs, the liquid crystal side rib 313 a and the short rib 314 , are provided as the protrusions protruding toward the upper panel 311 from the lower panel 312 . However, the numbers of claws and ribs are not limited thereto. Alternatively, the number of the claws and that of the ribs may be different from each other or different from the example described above, or a single claw and a single rib may be provided. Furthermore, only the number of either the claws or the ribs may be more than one. Moreover, here, the description has been given of the display housing 21 having the opening provided therein, through which the display screen of the liquid crystal panel 32 is exposed. However, spacing and bending prevention by the locking claws and the ribs may be also applied to prevention of spacing and bending between simple housing walls having no such opening provided therein. Next, a structure of housing the inverter circuit board 33 in the lower panel 312 will be described. FIG. 28 is an enlarged view of the inverter circuit board in a housed state. Note that, in FIG. 28 , the liquid crystal panel 32 is detached from the lower panel 312 . As described above, in the lower panel 312 , the concave section 313 is provided, which is surrounded by multiple ribs including the liquid crystal side rib 313 a. Moreover, the inverter circuit board 33 is housed in the concave section 313 in the state of being covered with the retaining sheet 34 . Here, in this embodiment, the retaining sheet 34 covering the inverter circuit board 33 retains the inverter circuit board 33 within the concave section 313 . FIG. 29 illustrates a state where a portion, covering an upper side of the inverter circuit board, in the retaining sheet covering the inverter circuit board is opened. FIG. 30 illustrates a state where the inverter circuit board is taken out of the concave section 313 together with the retaining sheet. The retaining sheet 34 has a bottom portion 341 , a side portion 342 and an upper portion 343 . The bottom portion 341 covers a rear surface of the inverter circuit board 33 , which is opposed to a component mounting surface, and is provided between the rear surface of the inverter circuit board 33 and a bottom of the concave section 313 . The side portion 342 is bent toward the component mounting surface from the bottom portion 341 . The upper portion 343 is bent from the side portion 342 so as to cover the component mounting surface. In housing of the inverter circuit board 33 , a surface of the bottom portion 341 on the bottom side of the concave section 313 is attached to the bottom of the concave section 313 with a double-sided tape. Moreover, three rectangular protrusions 343 a are provided on an edge of the upper portion 343 . Moreover, two cutouts 313 a _ 2 and one protrusion hole 313 a _ 3 are provided on the liquid crystal side rib 313 a among the ribs forming the concave section 313 . In housing of the inverter circuit board 33 , the two left and right protrusions 343 a among the three protrusions 343 a are fitted into the two cutouts 313 a _ 2 as illustrated in FIG. 28 . Moreover, in housing of the inverter circuit board 33 , the center protrusion 343 a among the three protrusions 343 a is fitted into the one protrusion hole 313 a _ 3 as illustrated in FIG. 28 . Furthermore, a cushion member 344 for elastically pressing the inverter circuit board 33 is attached to a surface of the upper portion 343 on the inverter circuit board 33 side. When the inverter circuit board 33 is housed in the concave section 313 in the state of being covered with the retaining sheet 34 as illustrated in FIG. 28 , there occur the following actions: the bottom portion 341 is attached to the bottom of the concave section 313 ; the edge of the upper portion 343 is locked by fitting the three protrusions 343 a into the cutouts 313 a _ 2 and the protrusion hole 313 a _ 3 ; and the inverter circuit board 33 is pressed by the cushion member 344 . With these actions, the inverter circuit board 33 is retained in the concave section 313 . In this embodiment, a metal radiator plate 35 for diffusing heat produced by the inverter circuit board 33 is attached to the lower panel 312 , and a part of the radiator plate 35 extends into the concave section 313 . Further, the bottom portion 341 of the retaining sheet 34 made of an insulating material of the PET film also has a function of insulating the radiator plate 35 and the inverter circuit board 33 from each other. Here, it is conceivable to allow the retaining sheet 34 to have other functions than the insulating function unlike this embodiment. As a conceivable example, a retaining sheet of a different structure may be formed of a so-called graphite sheet that is a resin material containing graphite and has a good thermal diffusion property to diffuse heat produced by the inverter circuit board. Further, as another conceivable example, a retaining sheet of a different structure may be formed of a so-called radio wave absorbing sheet that is a resin material containing ferrite and has a good radio wave absorbing property to absorb electromagnetic noise generated by the inverter circuit board. Here, in the graphite sheet or the radio wave absorbing sheet, graphite or ferrite contained in the corresponding resin material is conductive. Thus, in order to secure insulation properties in each of the sheets, insulating layers made of an insulating material such as PET are generally formed on both surfaces of each sheet. Incidentally, the liquid crystal panel 32 of this embodiment illustrated in FIG. 26 is a single-lamp liquid crystal panel using one fluorescent lamp as a backlight. The inverter circuit board 33 is a single-lamp inverter circuit board corresponding to the single-lamp liquid crystal panel. Generally, as the liquid crystal panel used in the notebook personal computer, other than the single-lamp liquid crystal panel, there is a double-lamp liquid crystal panel using two fluorescent lamps. Since the single-lamp liquid crystal panel and the double-lamp liquid crystal panel often have the same external shape or the like, a common housing that allows the both types of liquid crystal panels to be attached thereto is desired in terms of reduction in manufacturing cost, and the like. On the other hand, external dimensions and the like of the inverter circuit board often differ between the single-lamp type and a double-lamp type. Conventionally, the inverter circuit board is often retained in the housing by screwing or the like. Thus, in many cases, screwing positions or the like for retaining the inverter circuit board differ between the single-lamp type and the double-lamp type. Therefore, conventionally, such a difference becomes a factor that hinders realization of the housing that may be commonly used for the single-lamp type and the double-lamp type. Meanwhile, in this embodiment, as a method for retaining the inverter circuit board 33 , the method for covering the inverter circuit board 33 with the retaining sheet 34 is adopted as described above. Thus, a conventional structure such as screw holes for retaining the inverter circuit board, which hinders common use of the housing between the single-lamp type and the double-lamp type, is no longer required in the display housing 31 of the display unit 30 . As a result, in this embodiment, a double-lamp inverter circuit board is housed and retained in the concave section 313 for housing the single-lamp inverter circuit board 33 to be described below. FIG. 31 illustrates a state where the single-lamp inverter circuit board also illustrated in FIG. 29 and the like and the double-lamp inverter circuit board are laid out. FIG. 32 illustrates a state where the double-lamp inverter circuit board is housed in the concave section for housing the single-lamp inverter circuit board. As illustrated in FIG. 31 , a double-lamp inverter circuit board 55 is longer and slightly wider than the single-lamp inverter circuit board 33 , which is adopted in this embodiment, due to differences in sizes and types of mounted components, the number thereof and the like therebetween. Here, as illustrated in FIG. 29 or the like, in this embodiment, the concave section 313 is formed to be slightly wider than the single-lamp inverter circuit board 33 . In this embodiment, the cushion member 344 attached to the upper portion 343 of the retaining sheet 34 also functions to prevent the single-lamp inverter circuit board 33 from moving within the wide concave section 313 . The width of the concave section 313 is designed with regard to the double-lamp inverter circuit board 55 which may possibly be housed therein. Thus, the concave section 313 has the width that allows the double-lamp inverter circuit board 55 to be just fitted therein as illustrated in FIG. 32 . For housing and retaining the double-lamp inverter circuit board 55 , the retaining sheet 34 used for housing and retaining the single-lamp inverter circuit board 33 is used as it is as illustrated in FIG. 32 . Specifically, the bottom portion 341 of the retaining sheet 34 is attached to the bottom of the concave section 313 with a double-sided tape, and the upper portion 343 covers a component mounting surface of the double-lamp inverter circuit board 55 . Moreover, the three protrusions 343 a are fitted into the two cutouts 313 a _ 2 and the one protrusion hole 313 a _ 3 in the liquid crystal side rib 313 a. In this event, the cushion member 344 attached to the upper portion 343 elastically presses the double-lamp inverter circuit board 55 . Thus, the double-lamp inverter circuit board 55 is retained in the concave section 313 as in the case of the single-lamp inverter circuit board 33 . As described above, in this embodiment, the display housing 31 having the single-lamp liquid crystal panel 32 and the single-lamp inverter circuit board 33 mounted therein may also be used for the double-lamp liquid crystal panel and the double-lamp inverter circuit board 55 . Thus, unlike the conventional case, it is no longer required to prepare housings for the respective types. As a result, manufacturing cost may be reduced. Note that the notebook personal computer 10 has been described above as an example of the electronic device. However, the electronic device of the present invention is not limited thereto. The electronic device may be other types of personal computers such as a desktop type or a laptop type, or may be a computer more sophisticated than the personal computer. Alternatively, the electronic device is not limited to the computer but may be household electrical appliances or the like. As described above, according to the embodiment, it is possible to obtain a housing where separation of housing walls and a warp of a wall due to an external force is efficiently prevented in a limited space, and also to realize an electronic device mounted with such a housing. All examples and conditional language recited herein are intended for pedagogical purposes to aid the reader in understanding the invention and the concepts contributed by the inventor to furthering the art, and are to be construed as being without limitation to such specifically recited examples and conditions, nor does the organization of such examples in the specification relate to a showing of the superiority and inferiority of the invention. Although the embodiments of the present invention have been described in detail, it should be understood that the various changes, substitutions, and alterations could be made hereto without departing from the spirit and scope of the invention.

A housing includes a pair of housing walls that face each other with an inner space therebetween. The housing further includes: a first projection that projects from a first housing wall of the pair of housing walls toward a second housing wall of the pair of housing walls and abuts the second housing wall; and a second projection that projects from the second housing wall toward the first housing wall and engages in the first projection thereby preventing separation of the pair of housing walls.

REFERENCE TO RELATED APPLICATION [0001] This application is a continuation-in-part of U.S. patent application Ser. No. 10/306,278 filed on Nov. 27, 2002, now U.S. patent______and of U.S. design patent application Ser. No. 29/189,455 filed on Sep. 5, 2003. The benefits of these earlier filing dates are claimed for all matter common therewith. BACKGROUND OF THE INVENTION [0002] 1. Field of the Invention [0003] The present invention relates to satellite dish antenna mounts, and more particularly to a conveniently transported mount assembly useful to combine into a dish antenna mount that may be generally fixed at various selected orientations. [0004] 2. Description of the Prior Art [0005] The transmission of television and other similar signals has gone through several evolutions, first in the form of broadband radio signal then followed by various land lines or cable networks. In each instance either the physical burden of various in-ground or overhead cables or the width of the useable electromagnetic spectrum have limited the number of available programming sources. The granulation of available programming bandwidths, however, has recently gone through a dramatic evolutionary step with the recent advent of transmission techniques relying on geosynchronous satellites each serving as the signal emitting source for a particular program grouping, this evolution then being further reinforced by legislation like the Telecommunications Act of 1996. [0006] In this latter method the satellites associated with each particular signal group are distributed equatorially above the Earth, with a singular line of sight set of coordinates then ascribed to each geographic location. These alignment coordinates are then used for orienting the sensing axes of highly polarized antennae generally known as a satellite dish. The fixed nature of the viewing coordinates has led to a generally universal, more or less permanent, installation process with the fixed satellite dish mounting structure positioned adjacent the residence that is serviced thereby and the installation process then providing the customer garnering mechanism for a particular program source. [0007] In typical practice the coordinates for each antenna location are expressed as a corrected magnetic North azimuth and degrees of elevation from the local horizontal plane. As a consequence installation facility has become generally widespread and along with the wide acceptance of satellite programming by fixed residences there has also now emerged a robust trend to implement movable structures like recreational vehicles or motor homes with deployable antenna mounts. These deployable mounts most often follow the earlier practices of satellite based surveying or measuring antennae typically supported on an adjustable tripod, such as those described in U.S. Pat. No. 4,767,090 issued to Hartman, et al.; U.S. Pat. No. 5,249,766 issued to Vogt; U.S. Pat. No. 5,614,918 issued to Dinardo, et al.; U.S. Pat. No. 5,769,370 issued to Ashjace; U.S. Pat. No. 6,450,464 issued to Thomas; and others. Similar tripod mounted structures are also commercially sold, as for example the tripod mount sold under the model designation TR-2000 Tripod/Base Mount by the Winegard Company, 3000 Kirkwood Street, Burlington, Iowa 52601-2000. While suitable for the purposes intended each of the foregoing entail complex assortments of parts which include metal structures that distort or wholly obliterate any magnetic compass reading, while those made wholly of plastic like the antenna mount sold under the mark or model “The Buoy” by Camping World, Three Springs Road, P.O. Box 90017, Bowling Green, Ky. 42102-9017, lack the leveling indicia for alignment precision. Thus either the resulting measurement and erection complexity or lack of precision have unnecessarily detracted from the use convenience and proliferation of the deployable mount has been less than ringing in the recent past. A conveniently assembled, variously supported mount structure is therefore extensively desired and it is one such structure that is disclosed herein. SUMMARY OF THE INVENTION [0008] Accordingly, it is the general purpose and object of the present invention to provide an erectable antenna mount assembly all the parts thereof being formed from non-magnetic materials. [0009] Other objects of the present invention are to provide a conveniently erected antenna mount assembly supported on a base container that is selectively ballasted by storing water therein. [0010] Further objects of the invention are to provide an array of cooperating parts that are conveniently interlocked and thereafter aligned to support an antenna dish. [0011] Yet additional objects of the invention are to provide an interlocking array of parts that is easily assembled to form a satellite dish antenna mount provided with structural interlocks that are engaged without substantial ambiguity. [0012] Further and other objects of the invention are to adapt a portable dish antenna mount assembly for various mounting applications. [0013] Briefly, these and other objects are accomplished within the present invention by providing a generally hollow base formed as an annular liquid container having the central opening therein keyed and dimensioned for conforming orthogonal receipt of a similarly keyed end of a cylindrical mount. The other end of the mount is then provided with a selectively releasable universal swivel fixed by threaded advancement of the bottom end of a support post extending therefrom. The support post, in turn, terminates at the other end in a dished cavity into which a leveling bubble assembly is placed which is then useful to align the support post on the cylindrical mount to a generally vertical alignment regardless of the inclination of the hollow base. Once aligned the base is then filled with water to provide ballast fixing the base on the ground. [0014] Preferably the hollow base, the cylindrical mount and the support post are all formed of a polymeric material structure, such as polyvinyl chloride or other generally rigid polymer structure having material properties that allow the machining and cutting thereof Similarly, the pivoting mechanism fixing the support post alignment relative the cylindrical mount also comprises non-magnetic components, the non-ferrous assembly therefore allowing use of an inexpensive magnetic compass to assist in the orientation of the base along a predetermined azimuth. In this manner the induced magnetic distortion errors that are usually associated with unwanted distortions of the local magnetic field are wholly avoided. This cooperative structural arrangement is further simplified by way of a threaded extension of the mounting post into a domed ball surface captured between a cap on the end of the cylindrical mount by a helical spring and a dished surface within the cylinder opposing the threaded extension or the post so that a partial turn thereof then provides the frictional interlock to fix its generally vertical alignment as determined by the bubble level seated in the free end of the post. A satellite dish antenna, conventionally provided with elevation adjustment, can then be fixed to the mounting post along the azimuth referenced to the compass. [0015] One will appreciate that the planform of the base container and its several surfaces may be variously shaped for clear visual indication of the azimuth alignment thereof Moreover various storage provisions may be formed in the surfaces of the container that retain the compass and the component array of the cylindrical support assembly. In this manner a convenient, easily transported and easily aligned antenna mount assembly is provided that is useful at all geographic locations. [0016] It is to be noted that the utility of the foregoing mount assembly is particularly effective in a mobile setting and an alternative attachment structure is therefore provided conformed for engagement to the ladder parts and hand-hold structures of recreational vehicle. For those traveling by water where boat movement even when at the dock precludes useful reception an arrangement is provided that conveniently attaches the base to the typical triangular lid of a dock box. In these applications the three supports of the hollow base may be provided with extendable laniards that are then tied to the lid or, alternatively, a three legged platform may be provided of a planform similar to the above hollow base, the platform again including a central mounting aperture for receiving the cylindrical mount and also several openings along the edge to be engaged by elastic cords again capturing the lid. In this manner wide utility is obtained in a minimal complement. BRIEF DESCRIPTION OF THE DRAWINGS [0017] [0017]FIG. 1 is a perspective illustration, separated by parts, of the inventive satellite dish antenna mount assembly; [0018] [0018]FIG. 2 is yet another perspective illustration of the inventive antenna mount assembly in its deployed form; [0019] [0019]FIG. 3 is a sectional detail view taken along line 3 - 3 of FIG. 2; [0020] [0020]FIG. 4 is a plan view illustration of the inventive antenna mount assembly in its collapsed form for convenient storage; [0021] [0021]FIG. 5 is a side view of the collapsed assembly shown in FIG. 4; [0022] [0022]FIG. 6 is yet a further perspective illustration of an alternative implementation of the inventive mount assembly conformed for attachment to the top cover of a dock storage box; [0023] [0023]FIGS. 7 a and 7 b are each perspective illustrations, separated by parts, of a mounting adapter sub-assembly useful to support the inventive mount from either a vertical or a horizontal structural member of a recreational vehicle; [0024] [0024]FIG. 8 is a sectional view taken along line 8 - 8 of FIG. 2 illustrating a further alternative configuration for fixing the post assembly in the base of the inventive mount; [0025] [0025]FIG. 9 is a perspective illustration, once more separated by parts, of mounting adapter for rendering more convenient the installation of the satellite dish assembly onto the inventive mount; and [0026] [0026]FIGS. 10 a , 10 b and 10 c are each perspective details of a further mounting attachment. DESCRIPTION OF THE PREFERRED EMBODIMENT [0027] As shown in FIGS. 1 through 5, the inventive antenna mount assembly, generally designated by the numeral 10 , includes a hollow base container 11 of a generally triangular planform provided with a vertically aligned circular annulus 12 radially deformed to include a keyway 13 , thus forming a triangular enclosure supported on pads 14 along its bottom surface 15 at each apex of the triangle. The upper surface 16 of the container 11 , in turn, is provided with a circular depression 17 conformed for fitted receipt of a magnetic compass 20 adjacent one rear panel 19 of the container which further includes in opposed alignment at the distally opposite apex a fill opening 21 a closed by a threaded cap 21 , thus forming an enclosure into which water can be selectively admitted to weigh down the base and thereafter drained out before transport. [0028] The generally elongate rear surface 19 may also serve as a storage panel for the other components of the assembly 10 , including the storage of a cylindrical mount assembly 40 effected by hoop-and-pile strips 31 a and 31 b adhered on surface 19 engaging a similar strip 31 c on the exterior of a cylindrical segment 41 forming the primary support element of mount assembly 40 . Upon arrival to the placement site or terrain PT where the satellite dish antenna is to be deployed, the mount assembly 40 is released from this captive engagement and then fixed in the annulus 12 of the base container 11 by inserting the lower end 41 a of the cylindrical segment 41 therein. The upper end 41 b of segment 41 is then useful to deploy an adjustably securable universal pivot structure generally shown at 45 , described in more detail below, above the base with the receiving orientation of segment 41 in annulus 12 fixed by a projecting key 41 c inserted in the keyway 13 that is also aligned with a north-south orientation of the compass azimuth and the planform position of the fill opening 21 a . Thus a coordinated north-south orientation is provided in the alignment of the magnetic compass 20 and also in the orientation of the apex marked by the fill opening 21 a relative the rear surface 19 . Once the assembly is thus generally aligned the final adjustment to a vertical orientation is effected by manual movement of an adjustable mounting post 49 that projects from the universal pivot structure 45 with the assistance of a bubble level 25 seated in the free end of the post. The assembly is then in position to support the conventionally vended antenna dish assembly AD that itself includes further provisions for the final elevation and azimuth adjustments. [0029] Those in the art will appreciate that an equatorial geosynchronous satellite transmission system will invariably entail a generally southward antenna focus for all receiving antennae in the northern hemisphere of the Earth while those viewing in the southern hemisphere will necessarily be pointing generally northward. Thus a well indicated north-south orientation greatly assists in selecting the desired terrain on which the assembly is erected, particularly since the range of any adjustment is always limited. To further assist in the final alignment of the dish AD the pivot assembly 45 may also include azimuth markings AZ about its periphery geometrically referenced through the keyed insertion of the cylindrical segment. Thus all the necessary indicia are imbedded in the inventive assembly which is then fixed by water ballast in the base. [0030] In more detail, pivot structure 45 is defined by an end cap 46 mounted onto the upper end 41 b of segment 41 to capture therebetween a generally hemispherical, centrally threaded pivot base 47 engaged by a threaded projection 48 extending axially from the mounting post 49 into the interior of cap 46 through a chamfered opening 46 a . The interior surface of the segment's upper end is further provided with an internal seat or shoulder 41 d supporting the peripheral edge a circular dished plate 52 aligned to oppose and thus limit the threaded advancement of projection 48 through the pivot base 47 . A helical spring 51 compressed between plate 52 and the pivot base 47 then maintains frictional contact between the pivot base and the interior surface of cap 46 , right at the chamfered edge of the opening 46 a , and the dished arc of plate 52 , selected to match the pivot arc of projection 48 , is then useful to lock the post alignment with a small, fractional further turn advancing projection 48 against plate 52 , thus providing a convenient locking mechanism fixing the post relative the cylinder 41 . This conveniently locked and unlocked final alignment of the post 49 is made with concurrent visual reference to the bubble level 25 received in the free end of the post. Once thus aligned to a vertical alignment and locked, the mounting post is then captured by the clamping attachment CA normally provided with the antenna dish AD, fixing the antenna along the specified azimuth and elevation. This azimuth selection may be further assisted by scribing the exterior of cap 46 with the compass markings AZ that are coordinated with the compass alignment in the base. [0031] It will be appreciated that the foregoing structure may be conveniently formed thereof can be effected by well known adhesive processes. Moreover, by selecting conventional pipe dimensions commercially vended water conveying or electrical pipe can be utilized along with all the conventional fittings and caps that are concurrently vended therewith. The hook-and-pile strips are similarly of conventional form, often referred to by their mark or style “Velcro” and variously distributed as strips provided with adhesive backing. Thus widely available, conveniently formed and assembled components are combined to form an antenna mount that is easily and accurately deployed. [0032] By reference to FIGS. 6 through 10 c several adaptations and modifications can be included in the inventive mount assembly disclosed herein to further expand the usefulness and convenience thereof. For example, the inventive mount assembly can be conveniently adapted for marine use in accordance with the teaching hereinafter set out by particular reference to FIG. 6. Like numbered parts functioning in like manner to that previously described the mount assembly 40 is modified at the lower end of the cylindrical segment 41 to engage an annulus 112 in a triangular platform 111 which on its opposing lower surface 115 is provided with support legs 116 cushioned at their ends by pads 116 a when in position on the top cover TC of a dock box DB normally found in a marina. A set of perforations 117 along the edges of the platform 111 are then useful to secure the ends of a plurality of elastic straps 118 which at their other ends then engage the periphery PE of the top cover TC. [0033] Of course, while this secured attachment obviates the need for a ballasted base structure it is contemplated within the teachings herein that the hollow base container 11 may be similarly provisioned with attachments illustrated in FIGS. 10 a through 10 c that may also be useful to secure same to the top of the dock box. [0034] The portability of the instant mount assembly may be also rendered useful with motor homes or recreational vehicles that are stabilized at the temporary site by deployable hydraulic or mechanical supports. Once so stabilized the recreational vehicle RV provides the necessary base from which the mount assembly can then be deployed. To render convenient the attachment of the mount assembly to various structural members of the stabilized vehicle RV a mounting adapter 210 is shown in FIGS. 7 a and 7 b comprising two mating clam shell halves 211 and 212 defining a common recess which is then clamped onto a horizontal or vertical structural element HE or VE. A set of clamping screws 213 and 214 then extend through the mated shell halves to threadably engage one of two threaded opening sets 215 or 216 in the end of a fitting 220 provided with a split bore 221 conformed to receive the end of the cylindrical segment 41 where it is clamped by a clamping screw 223 . In this manner the satellite dish can be deployed directly from a structure like a ladder or luggage rack on the vehicle RV. [0035] In all the foregoing implementations alternative engagement modes may be utilized to secure the end of the post assembly 40 in the corresponding base. For example, as illustrated in FIG. 8 a mismatched taper may be provided to the lower end portion 41 a (or 141 a ) of the cylindrical segment 41 and the annulus 12 (or 112 ) threadably drawn to an interference fit by advancing a threaded apex 41 c into a similarly threaded end opening 12 c in the annulus. This manner of engagement may assist in the assembly convenience of an interlocked structure while also reducing the necessary precision in the mating parts. [0036] Similar simplifications can be effected in the mounting structure of the dish assembly AD as illustrated in FIG. 9. In this modification a tubular sleeve 149 is provided including an interior bore 149 a conformed to the exterior dimensions of the post 49 . The sleeve is then clamped in the dish mounting assembly CA and a single cinch screw 149 b is then useful to secure the dish assembly AD to the mount. [0037] Further securing conveniences can be obtained in the structure of the hollow base container 11 as illustrated in FIGS. 8, 10 a , 10 b and 10 c . More precisely each of the base legs 14 may be provided with a threaded insert 14 a which then engages a resilient pad assembly 14 b provided with a threaded post 14 c . A cable loop 14 d is then selectively captured between the pad and the corresponding leg in a deployment subjacent the lower surface 15 or projecting beyond the base planform. When projecting to the exterior each of the loops may be engaged by the aforementioned elastic straps 118 for mounting on a dock locker or may be pinned to the ground by spikes 14 e. [0038] It will be appreciated that each of the foregoing variations and adaptations expand the utility of the inventive mount assembly as well as the convenience in its use. In this manner the task of erecting the satellite antenna in the course of travel is greatly simplified thus rendering the assembly convenient and useful. Of course this convenience is not just useful for television signal reception but also in the course of setting up portable satellite communication stations. [0039] Obviously, many modifications and variations can be effected without departing from the spirit of the invention instantly disclosed. It is therefore intended that the scope of the invention be determined solely by the claims appended hereto.

In an array of cooperating parts useful to form a portable satellite dish antenna mount base an assortment of attachments is provided to secure the base to a marina storage box, structural elements of a stabilized recreational vehicle and also to ground. At the same time the interface between the base and the mount itself may be tapered along interfering tapers to render the assembly and disassembly convenient. Once assembled an end mounting post on the mount is aligned to a vertical alignment with the assistance of a bubble level in the post end to support the dish antenna thereon. The base may further include a magnetic compass to aid in the antenna alignment.

This application is a continuation-in-part of application Ser. No. 08/871,347, filed Jun. 9, 1997, now U.S. Pat. No. 5,916,780. BACKGROUND OF THE INVENTION 1. Field of the Invention This invention relates to the production of fuel alcohol from cellulose. More specifically, this invention relates to the pretreatment of cellulose feedstocks for ethanol production. The pretreatment reaction of feedstocks chosen with a ratio of arabinan plus xylan to non-starch polysaccharides (AX/NSP) of greater than about 0.39 produces a superior substrate for enzymatic hydrolysis than other feedstocks. These pretreated feedstocks are uniquely suited to ethanol production. Examples of feedstocks that could be chosen in such a pretreatment process include some varieties of oat hulls and corn cobs, and feedstocks selectively bred for high AX/NSP. 2. Brief Description of the Prior Art The possibility of producing ethanol from cellulose has received much attention due to the availability of large amounts of feedstock, the desirability of avoiding burning or landfilling the materials, and the cleanliness of the ethanol fuel. The advantages of such a process for society are described, for example in a cover story of the ATLANTIC MONTHLY, (April 1996). The natural cellulosic feedstocks for such a process typically are referred to as "biomass." Many types of biomass, including wood, agricultural residues, herbaceous crops, and municipal solid wastes, have been considered as feedstocks for ethanol production. These materials primarily consist of cellulose, hemicellulose, and lignin. This invention is concerned with converting the cellulose to ethanol. The familiar corn starch-to-ethanol process, in which the starch is converted to ethanol using sulfurous acid and amylase enzymes, lies outside the scope of this invention. Cellulose is a polymer of the simple sugar glucose connected by beta 1,4 linkages. Cellulose is very resistant to degradation or depolymerization by acid, enzymes, or micro-organisms. Once the cellulose is converted to glucose, the resulting sugar is easily fermented to ethanol using yeast. The difficult challenge of the process is to convert the cellulose to glucose. The oldest methods studied to convert cellulose to glucose are based on acid hydrolysis (review by Grethlein, Chemical Breakdown Of Cellulosic Materials, J. APPL. CHEM. BIOTECHNOL. 28:296-308 (1978)). This process can involve the use of concentrated or dilute acids. The concentrated acid process uses 72%, by weight, sulfuric acid or 42%, by weight, hydrochloric acid at room temperature to dissolve the cellulose, followed by dilution to 1% acid and heating to 100° C. to 120° C. for up to three hours to convert cellulose oligomers to glucose monomers. This process produces a high yield of glucose, but the recovery of the acid, the specialized materials of construction required, and the need to minimize water in the system are serious disadvantages of this process. Similar problems are encountered when concentrated organic solvents are used for cellulose conversion. The dilute acid process uses 0.5% to 2%, by weight, sulfuric acid at 180° C. to 240° C. for several minutes to several hours. BRINK (U.S. Pat. Nos. 5,221,537 and 5,536,325) describes a two-step process for the acid hydrolysis of lignocellulosic material to glucose. The first (mild) step depolymerizes the hemicellulose to xylose and other sugars. The second step depolymerizes the cellulose to glucose. The low levels of acid overcome the need for chemical recovery. However, the maximum glucose yield is only about 55% of the cellulose, and a high degree of production of degradation products can inhibit the fermentation to ethanol by yeast. These problems have prevented the dilute acid hydrolysis process from reaching commercialization. To overcome the problems of the acid hydrolysis process, cellulose conversion processes have been developed using two steps: (1) a pretreatment, and (2) a treatment comprising enzymatic hydrolysis. The purpose of pretreatment is not to hydrolyze the cellulose completely to glucose but, rather, to break down the integrity of the fiber structure and make the cellulose more accessible to attack by cellulase enzymes in the treatment phase. After a typical pretreatment of this type, the substrate has a muddy texture. Pretreated materials also look somewhat similar to paper pulp, but with shorter fibers and more apparent physical destruction of the feedstock. The goal of most pretreatment methods is to deliver a sufficient combination of mechanical and chemical action, so as to disrupt the fiber structure and improve the accessibility of the feedstock to cellulase enzymes. Mechanical action typically includes the use of pressure, grinding, milling, agitation, shredding, compression/expansion, or other types of mechanical action. Chemical action typically includes the use of heat (often steam), acid, and solvents. Several known pretreatment devices will be discussed below, and with specific reference to extruders, pressurized vessels, and batch reactors. A typical treatment by enzymatic hydrolysis is carried out by mixing the substrate and water to achieve a slurry of 5% to 12%, by weight of cellulose, and then adding cellulase enzymes. Typically, the hydrolysis is run for 24 to 150 hours at 50° C., pH 5. At the end of the hydrolysis, glucose, which is water soluble, is in the liquid while unconverted cellulose, lignin, and other insoluble portions of the substrate remain in suspension. The glucose syrup is recovered by filtering the hydrolysis slurry; some washing of the fiber solids is carried out to increase the yield of glucose. The glucose syrup is then fermented to ethanol by yeast, and the ethanol recovered by distillation or other means. The ethanol fermentation and recovery are by well-established processes used in the alcohol industry. The two-step process of pretreatment plus enzyme hydrolysis overcomes many of the problems associated with a single harsh acid hydrolysis. The specific action of the enzymes decreases the amount of degradation products and increases the yield of glucose. In addition, the fact that the pretreatment for fiber destruction is milder than that for cellulose hydrolysis means that lower chemical loadings can be used, decreasing the need for chemical recovery, and a lower amount of degradation products are made, increasing the yield and decreasing the inhibition of fermentation to ethanol by yeast. Unfortunately, to date the approach of a pretreatment and an enzyme hydrolysis treatment has not been able to produce glucose at a sufficiently low cost, so as to make a fermentation to ethanol commercially attractive. Even with the most efficient currently known pretreatment processes, the amount of cellulase enzyme required to convert the cellulose to glucose is so high as to be cost-prohibitive for ethanol production purposes. Several approaches have been taken to attempt to decrease the amount of cellulase enzyme required. The approach of simply adding less cellulase to the system decreases the amount of glucose produced to an unacceptable extent. The approach of decreasing the amount of enzyme required by increasing the length of time that the enzyme acts on the feedstock leads to uneconomical process productivity, stemming from the high cost of hydrolysis tanks. The approach of reducing the amount of cellulase enzyme required by carrying out cellulose hydrolysis simultaneously with fermentation of the glucose by yeast is also inefficient. The so-called simultaneous saccharification and fermentation (SSF) process is not yet commercially viable because the optimum operating temperature for yeast, 28° C., is too far below the optimum 50° C. conditions required by cellulase. Operating a SSF system at a compromise temperature of 37° C. is also inefficient, and invites microbial contamination. The desire for a cost-effective ethanol production process has motivated a large amount of research into developing effective pretreatment systems. Such a pretreatment system would achieve all of the advantages of current pretreatments, including low production of degradation products and low requirements for chemical recovery, but with a sufficiently low requirement for cellulase enzymes so as to make the process economical. The performance of a pretreatment system is characterized strictly by the amount of enzyme required to hydrolyze an amount of cellulose to glucose. Pretreatment A performs better than pretreatment B, if A requires less enzyme to produce a given yield of glucose than B. The early work in pretreatment focused on the construction of a working device and determination of the conditions for the best performance. One of the leading approaches to pretreatment is by steam explosion, using the process conditions described by FOODY (U.S. Pat. No. 4,461,648), which is incorporated herein by reference. In the FOODY process, biomass is loaded into a vessel known as a steam gun. Up to 1% acid is optionally added to the biomass in the steam gun or in a presoak. The steam gun is then filled very quickly with steam and held at high pressure for a set length of time, known as the cooking time. Once the cooking time elapses, the vessel is depressurized rapidly to expel the pretreated biomass, hence the terminology "steam explosion" and "steam gun". In the FOODY process, the performance of the pretreatment depends on the cooking time, the cooking temperature, the concentration of acid used, and the particle size of the feedstock. The recommended pretreatment conditions in the FOODY process are similar for all the cellulosic feedstocks tested (hardwood, wheat straw, and bagasse) provided they are divided into fine particles. Furthermore, the cooking temperature is determined by the pressure of the saturated steam fed into the steam gun. Therefore, the practical operating variables that effect the performance of the pretreatment are the steam pressure, cooking time, and acid concentration. The FOODY process describes combinations of these variables for optimum performance; as one might expect, increasing the time decreases the temperature used, and vice versa. The range of steam pressure taught by FOODY is 250 psig to 1000 psig, which corresponds to temperatures of 208° C. to 285° C. Another published study of steam explosion pretreatment parameters is Foody, et al, Final Report, Optimization of Steam Explosion Pretreatment, U.S. DEPARTMENT OF ENERGY REPORT ET230501 (April 1980). This study reported the effects of the pretreatment variables of temperature (steam pressure), particle size, moisture content, pre-conditioning, die configuration, and lignin content. The optimized steam explosion conditions were reported for three types of straws, five species of hardwood, and four crop residues. The optimum pretreatment conditions as published by FOODY were subsequently confirmed by others using other feedstocks and different equipment. For example, GRETHLEIN (U.S. Pat No. 4,237,226), describes pretreatment of oak, newsprint, poplar, and corn stover by a continuous plug-flow reactor, a device that is similar to an extruder. Rotating screws convey a feedstock slurry through a small orifice, where mechanical and chemical action break down the fibers. GRETHLEIN specifies required orifice sizes, system pressures, temperatures (180° C. to 300°C.), residence times (up to 5 minutes), acid concentrations (up to 1% sulfuric acid) and particle sizes (preferred 60 mesh). GRETHLEIN obtained similar results for all of the specified substrates he identified (See Column 3, line 30). Even though the GRETHLEIN device is quite different from the steam gun of FOODY, the time, temperature, and acid concentration for optimum performance are similar. More recent work has focused on understanding the means by which pretreatment improves the enzymatic hydrolysis of a given substrate. BRINK (U.S. Pat. No. 5,628,830) describes the pretreatment of lignocellulosic material by using a steam process to break down the hemicellulose and following with hydrolysis of the cellulose using cellulase enzymes. The first explanation offered to characterize the advantage of a pretreatment was that a pretreatment should be evaluated on the amount of lignin removed, with better performance associated with higher degrees of delignification. See Fan, Gharpuray, and Lee, Evaluation Of Pretreatments For Enzymatic Conversion Of Agricultural Residues, PROCEEDINGS OF THE THIRD SYMPOSIUM ON BIOTECHNOLOGY IN ENERGY PRODUCTION AND CONSERVATION, (Gatlinburg, Tenn., May 12-15, 1981). The notion that delignification alone characterizes pretreatment was also reported by Cunningham, et al, PROCEEDINGS OF THE SEVENTH SYMPOSIUM ON BIOTECHNOLOGY FOR FUELS AND CHEMICALS, (Gatlinburg, Tenn., May 14-17, 1985). Grethlein and Converse, Common Aspects of Acid Prehydrolysis and Steam Explosion for Pretreating Wood, BIORESOURCE TECHNOLOGY 36(2):77-82 (1991), put forth the proposition that the degree of delignification is important only for previously dried substrates and, therefore, not a relevant consideration to most pretreatment processes that use undried feedstocks. Knappert, et al, A Partial Acid Hydrolysis of Cellulosic Materials as a Pretreatment for Enzymatic Hydrolysis, BIOTECHNOLOGY AND BIOENGINEERING 23:1449-1463 (1980) reported that the increased susceptibility to enzyme hydrolysis after pretreatment is caused by the creation of micropores by the removal of the hemicellulose, a change in crystallinity of the substrate, and a gross reduction in the degree of polymerization of the cellulose molecule. Grohmann, et al, Optimization of Dilute Acid Pretreatment of Biomass, SEVENTH Symposium ON BIOTECHNOLOGY FOR FUELS AND CHEMICALS (Gatlinburg, Tenn., May 14-17, 1985) specifically supported one of the hypotheses of Knappert, et al by showing that removal of hemicellulose in pretreatment results in improved enzymatic hydrolysis of the feedstock. (See p.59-80). Grohmann, et al worked with wheat straw and aspen wood at temperatures of 95° C. to 160° C. and cooking times of up to 21 hours. For both feedstocks, about 80% of the cellulose was digested by cellulase enzymes after optimum pretreatments, in which 80% to 90% of the xylan was removed from the initial material. Grohmann and Converse also report ed that the crystallinity index of the cellulose was not changed significantly by pretreatment. They further reported that pretreatments can create a wide range of degrees of polymerization while resulting in similar susceptibility to enzymatic hydrolysis. Another alternative explanation offered for the improvements in enzymatic hydrolysis due to pretreatment is the increase in surface area of the substrate. Grethlein and Converse refined this explanation by showing that the surface area that is relevant is that which is accessible to the cellulase enzyme, which has a size of about 51 angstroms. The total surface area, which is measured by the accessibility of small molecules such as nitrogen, does not correlate with the rate of enzymatic hydrolysis of the substrate, for the reason that small pores that do not allow the enzyme to penetrate do not influence the rate of hydrolysis. In spite of a good understanding of devices and optimum conditions for pretreatment, and a large quantity of research into the mechanism of a pretreatment process, there still does not exist an adequate pretreatment for a commercially feasible process to convert cellulosic materials to ethanol. Such a pretreatment process would be of enormous benefit in bringing the cellulose-to-ethanol process to commercial viability. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1. A graph of cellulose conversion for certain feedstocks after pretreatment reaction at 121° C., as a function of AX/NSP of the initial material, according to EXAMPLE 3. FIG. 2. A graph of cellulose conversion for certain feedstocks after pretreatment reaction at 230° C., as a function of AX/NSP of the initial material, according to EXAMPLE 4. SUMMARY OF THE INVENTION The inventors have discovered that a critical property of a feedstock determines its relative cellulase enzyme requirement to convert the cellulose to glucose after the pretreatment reaction. That property is the ratio of arabinan plus xylan to total nonstarch polysaccharides, which we will refer to hereinafter as "AX/NSP." The inventors have discovered that the higher the AX/NSP, the less cellulase enzyme is required after the pretreatment reaction, and hence the more economical the production of ethanol. Feedstocks with AX/NSP over about 0.39 are particularly well suited for a cellulose-to-ethanol process. Examples of such feedstocks are certain varieties of oat hulls and corn cobs. Based on this discovery, the inventors have developed improved pretreatment processes prior to enzyme treatment that converts a lignocellulosic feedstock to ethanol. One such process consists essentially of the steps: 1. Choosing a lignocellulosic feedstock with a ratio of arabinan plus xylan to total nonstarch polysaccharides (abbreviated AX/NSP) of greater than 0.39. 2. Reacting the chosen feedstock at conditions which disrupt the fiber structure and effect an hydrolysis upon portions of both cellulose and hemicellulose, so as to improve digestibility of the pretreated feedstock by a subsequent cellulase enzyme treatment. A second such process consists essentially of the steps: 1. Choosing a lignocellulosic feedstock selectively bred to have a relatively increased ratio of arabinan plus xylan to total nonstarch polysaccharides (AX/NSP). 2. Reacting the chosen feedstock at conditions which disrupt the fiber structure and effect an hydrolysis upon portions of both cellulose and hemicellulose, so as to improve digestibility of the pretreated feedstock by a subsequent cellulase enzyme treatment. Once a feedstock is chosen based on high AX/NSP, the pretreatment reactions can be carried out in a manner consistent with previous reports. This might include single stage or two stage reactions in steam guns, extruders, or other devices used previously. By choosing the feedstock based on AX/NSP, the resulting cellulase enzyme requirement after the pretreatment reaction is significantly lower than otherwise required. This results in significant savings in the cost of producing ethanol from lignocellulosic materials. There have been no previous reports of the superior performance after pretreatment of feedstocks specifically chosen because of any particular level of AX/NSP, let alone an AX/NSP level that is greater than 0.39, by weight. The present invention is very surprising in view of the U.S. D.O.E. study by FOODY, et al, supra, which observed no correlation between xylan content of the feedstocks and glucose yield after steam explosion and hydrolysis by cellulase. FOODY, et al was a study of thirteen feedstocks. The resulting conversion of cellulose to glucose varied widely among the pretreated feedstocks, between 46% to 50% for oak and sunflower stalks to 86% to 87% for barley straw and maple. The two best feedstocks of FOODY et al, barley straw and maple wood, had xylan contents of 31% and 19%, respectively, which were among the highest and lowest values reported. Oak and aspen both contained 21% xylan, yet they achieved widely differing glucose yields after hydrolysis by cellulase, 46% and 72%, respectively. The present invention also is very surprising in view of the patent to GRETHLEIN, supra. GRETHLEIN described a device for the pretreatment of feedstocks using dilute sulfuric acid All four of the GRETHLEIN feedstocks (oak, newsprint, poplar, and corn stover) performed similarly (Column 3, lines 25 to 32). This reported result is exactly contrary to the teachings of the present invention, who have found and identified a novel feedstock property, AX/NSP, that can reliably be used to predict the performance of the feedstocks after treatment. The present invention also is very surprising in view of the publication by Knappert, et al., supra, which reviewed four feedstocks: Solka floc, newsprint, oak, and corn stover. Knappert, et al obtained optimum yields of glucose from cellulose after pretreatment reactions. One hundred percent yield was obtained from newsprint, corn stover, and oak, and 81% yield was obtained from Solka floc (Tables I and II, page 1453-1457). As the only feedstocks with cellulose and xylan content reported were newsprint and Solka floc, this study simply does not address the relationship between AX/NSP of the feedstock and the digestibility of the material by cellulase enzymes after pretreatment reaction. The present invention actually suggests that the teachings of Knappert, et al are incorrect. At the very least, the teachings of Knappert, et al are at odds with the teachings of the present invention. Knappert et al taught that a low hemicellulose content of a material presages little improvement in cellulose digestibility during pretreatment. The present invention, at EXAMPLE 5, shows a large improvement in the digestibility of oat hulls with pretreatment reaction after the hemicellulose has been removed by a mild reaction. SUMMARY OF TERMINOLOGY The invention and preferred embodiments described hereafter are to be construed using certain terms as hereafter defined, for purposes of the present invention. Lignocellulosic feedstock means any raw material that one might consider for a cellulose-to-ethanol process. Such a material has at least about 25% cellulose, and the cellulose is substantially converted to glucose and then ethanol in the process. Typical lignocellulosic feedstocks materials are wood, grains, and agricultural waste. For the present purposes there are no specifications on the lignin, starch, protein, or ash content. Examples of lignocellulosic feedstocks that have been considered for an ethanol process are wood, grasses, straws, and crop waste. Often, a lignocellulosic feedstock originates from one species of fiber. However, for present purposes the lignocellulosic feedstock can be a mixture that originates from a number of different species. Conversion to fuel ethanol denotes the conversion of at least about 40% of the cellulose to glucose, and then fermentation of the glucose to ethanol. For the present purposes there are no specifications on the conversion products made from the lignin or the hemicellulose. In a preferred embodiment, at least 60% of the cellulose is converted to glucose and fermented to ethanol. Xylan and xylan content are the terms used to express the quantity of anhydroxylose present in the feedstock. Much of the anhydroxylose is present as a linear beta 1,4-linked polysaccharide of xylose, but the designation xylan is not limited to anhydroxylose of this structure. Arabinan and arabinan content are the terms used to express the quantity of anhydroarabinose present in the feedstock. Much of the anhydroarabinose is present as a branched alpha 1,3-linked polysaccharide of arabinose, but the designation arabinan is not limited to anhydroarabinose of this structure. Arabinan plus xylan refers to the sum of the arabinan content and the xylan content of the feedstock. This is distinguished from the term arabinoxylan, which refers to an alpha 1,3-linked polymer of arabinose and xylose. Arabinoxylan is a specific example of arabinan and xylan, but does not comprise all possible forms of arabinan and xylan. Hemicellulose is a general term that includes all natural polysaccharides except cellulose and starch. The term includes polymers of xylose, arabinose, galactose, mannose, etc. and mixtures thereof. In the present work, the primary constituents of the hemicellulose are arabinose and xylose. AX/NSP is the ratio of arabinan plus xylan to non-starch polysaccharides and can be measured for any feedstock based on the analytical procedures described herein. AX/NSP is calculated from EQUATION (1): AX/NSP=(xylan+arabinan)/(xylan+arabinan+cellulose) (1) where the xylan, arabinan, and cellulose contents of the feedstocks are measured according to the procedures in EXAMPLE 1 and AX/NSP is calculated as shown in EXAMPLE 1. AX/NSP is taught herein to characterize the performance of the pretreatment. The higher the AX/NSP, the less cellulase enzyme is required to hydrolyze the cellulose to glucose after a given pretreatment. The pretreatment performance is particularly good for feedstocks with AX/NSP of greater than about 0.39. This point is illustrated in EXAMPLES 3 and 4. The AX/NSP content should be measured for each batch of a feedstock used, as it will no doubt vary seasonally and with the age, geographical location, and cultivar of the feedstock. Therefore, there are no absolute values of AX/NSP that are always valid for a given species. However, samples of oat hulls and corn cobs exhibited the highest AX/NSP in the data collected, as well as the highest performance in pretreatment. Oat hulls and corn cobs from the lots sampled would therefore be preferred feedstocks for an ethanol process. The theoretical upper limit of AX/NSP is 0.75. This would be present in a material that was 25% cellulose and 75% arabinan plus xylan. The inventors know of no materials with this composition. The highest AX/NSP observed by the inventors is 0.422 . The hemicellulose, cellulose, arabinan, and xylan content of various materials have been widely published. However, the analytical methods used can greatly influence the apparent composition, and these publications are often based on widely varying methods. Therefore, these publications can be relied on only to give a general idea as to the approximate composition of these materials. For the purposes of practicing the invention, the same analytical methods must be applied to each candidate feedstock, and those of Example 1 are preferred for the absolute values being claimed. In practicing the invention, feedstocks with high AX/NSP can be identified by two generic methods: (1) by screening of natural fibers and grains, and (2) by screening of varieties selectively bred for higher AX/NSP levels. Reaction or Pretreatment reaction refers to a chemical process used to modify a lignocellulosic feedstock to make it more amenable to hydrolysis by cellulase enzymes. In the absence of pretreatment, the amount of cellulase enzyme required to produce glucose is impractical. Improve digestibility by cellulose enzymes by disrupting the fiber structure and effecting the hydrolysis of a portion of the hemicellulose and the cellulose. This terminology refers to the physical and chemical changes to the feedstock caused by the pretreatment reaction. At a minimum, pretreatment increases the amount of glucose hydrolyzed from the feedstock by cellulase, disrupts the fibers, and hydrolyzes some fraction of the cellulose and hemicellulose. The pretreatment process of the invention preferably is part of an integrated process to convert a lignocellulosic feedstock to ethanol. Such a process includes, after pretreatment, enzymatic hydrolysis of cellulose to glucose, fermentation of the glucose to ethanol, and recovery of the ethanol. Cellulose hydrolysis refers to the use of cellulase enzymes to convert the pretreated cellulose to glucose. In the present invention, a minority of the cellulose is hydrolyzed during the pretreatment, and the majority survives pretreatment and is subjected to hydrolysis by cellulase enzymes. The manner in which the enzymatic hydrolysis is carried out is not constrained by the invention, but preferred conditions are as follows. The hydrolysis is carried out in a slurry with water that is initially 5% to 12% cellulose and is maintained at pH 4.5 to 5.0 and 50° C. The cellulase enzymes used might be any of the commercial cellulases available, which are manufactured by IOGEN CORPORATION, NOVO NORDISK, GENENCOR INTERNATIONAL, PRIMALCO, and other companies. The cellulase enzymes might be supplemented with beta-glucosidase to complete the conversion of cellobiose to glucose. A commercial beta-glucosidase enzyme is NOVOZYM 188, sold by NOVO NORDISK. The skilled practitioner will realize that the amount of cellulase enzyme used in the hydrolysis is determined by the cost of the enzyme and the desired hydrolysis time, glucose yield, and glucose concentration, all of which are influenced by the process economics and will vary as each of the relevant technologies is evaluated. The typical enzyme dosage range is 1 to 50 Filter Paper Units (FPU) cellulase per gram cellulose for 12 to 128 hours. In a preferred embodiment the cellulase enzyme dosage is 1 to 10 FPU per gram cellulose. EXAMPLES 2 and 3 describe cellulose hydrolysis in more detail. In a preferred embodiment, cellulose hydrolysis and ethanol fermentation are carried out simultaneously, using those techniques generally employed in an SSF process, as discussed previously herein. Ethanol fermentation and recovery are carried out by conventional processes that are well known, such as yeast fermentation and distillation. The invention is not constrained by the manner in which these operations are carried out. DESCRIPTION OF PREFERRED EMBODIMENTS In practicing the invention, any type of feedstock, including but not limited to naturally occurring and selectively bred feedstock, can be employed. As emphasized above, the novelty of the present invention relates to the use of a high AX/NSP ratio, heretofore unrecognized as a critical standard for choosing optimum feedstocks for glucose and ethanol production; the origin of the feedstock is of secondary importance. In one embodiment, the feedstock is naturally occurring. In this case, the AX/NSP of the feedstock is measured by the method of Example 1. Feedstocks with AX/NSP of greater than about 0.39 are preferred for a cellulose-to-ethanol process. The AX/NSP content should be measured for each batch of a feedstock used, as it will no doubt vary seasonally and with age, geographic location, and cultivar of the feedstock. As experience with a given feedstock accumulates, the frequency of testing AX/NSP will lessen. In a preferred embodiment, the feedstock is not corn fiber (also known as corn kernel hulls). In a preferred embodiment, the starch content of the feedstock is less than 10%. Feedstocks with more than this level of starch will have severe sugar degradation in a pretreatment process designed for cellulose, and are better suited to glucose production using amylase enzymes. Starch content is measured by the method described in Example 1. In a more preferred embodiment, the starch content of the feedstock is less than 7%. In another preferred embodiment, the feedstock has already been selectively bred. In this case, the AX/NSP of the bred feedstock is measured by the method of Example 1 and compared with that of the natural feedstock. If the AX/NSP has been increased by breeding, the feedstock is more suitable for cellulose conversion than the natural or starting feedstock material. Such breeding can, in principle, be carried out by any of the common methods used to select for desired traits in plant breeding. These methods are summarized by H. B. Tukey, "Horticulture is a Great Green Carpet that Covers the Earth" in American Journal of Botany 44(3):279-289 (1957) and Ann M. Thayer, "Betting the Transgenic Farm" in Chemical and Engineering News, Apr. 28, 1997, p. 15-19. The methods include: 1. Scientific Breeding. Screen varieties of a species for a high level of AX/NSP and repeatedly grow those varieties which exhibit the trait. Selective breeding protocols directed to obtaining species that have a high level of AX/NSP may involve enhancing the levels of xylan within the species. 2. Chimeras. Graft two or more species and screen the resulting species for the level of AX/NSP. 3. Pollination breeding. Combine two or more species by cross pollination and screen for AX/NSP level. 4. Chemical thinning. Expose plants to chemical toxins such that only the fittest survive. Requires a toxin that is resisted by arabinan or xylan. 5. Induction. Expose species to conditions that induce higher levels of AX/NSP. 6. Environmental distress. Expose species to conditions that induce death unless protested by high levels of AX/NSP. 7. Nutrition and fertilizers. Develop nutritional regimen to increase AX/NSP. 8. Genetic engineering. Genetically modify a species so as to increase its level of AX/NSP. Specifically, the production of transgenic plants that express genes that result in high levels of AX/NSP within the plant. For example, such genetic modification may include, but is not limited to, genes encoding enzymes involved in enhancing the levels of xylan within the species. Constructs comprising genes of interest can be introduced into plant cells using for example, Ti plasmids, Ri plasmids, plant virus vectors, direct DNA transformation, microinjection, electroporation, etc. (Miki and Iyer, Fundamentals of Gene Transfer in Plants. In Plant Metabolism, 2d Ed. D T Dennis, D H Turpin, D D Lefebrve, D B Layzell (Eds.), Addison Wesly, Langmans Ltd. London, pp. 561-579 (1997).) In one preferred embodiment, the selectively bred feedstock is corn, oats, wheat, sugar cane, or a component of these. These materials are well suited to ethanol production and are widely available. In another preferred embodiment, the selectively bred feedstock is a C4 grass. C4 grasses are so classified by their pathway of carbon dioxide metabolism, which involves intermediates with 4 carbon atoms. This is described in Biology of Plants, by Raven, Evert, and Curtis, Worth Publishing Co., second edition, 1976, pages 116-117. Of the C4 grasses, preferred feedstocks are C4 perennial grasses. The perennial grasses do not require yearly planting and fertilization and are therefore more suitable for ethanol production than annual grasses. Of the C4 perennial grasses, the most preferred are switch grass, miscanthus, cord grass, and rye grass. These grasses are particularly fast growing. Cord grass is classified as a C4 grass even though a portion of its growth cycle uses C3 metabolism. In another preferred embodiment, the selectively bred lignocellulosic feedstock has an AX/NSP level that is greater than about 0.39, and such a selectively bred feedstock then is reacted to increase its digestibility by cellulase enzymes and converted to ethanol by hydrolyzing the cellulose to glucose with cellulase enzymes, fermenting the glucose, and recovering the ethanol. In another preferred embodiment, the selectively bred lignocellulosic feedstock has an increased AX/NSP level over a starting feedstock material, but still below 0.39. Such a selectively bred feedstock is then reacted to increase its digestibility to cellulase enzymes and converted to ethanol. The reason that increasing the AX/NSP content of a feedstock is beneficial, even if the level remains below 0.39, is that in certain geographical areas the climate supports the growth of only a narrow range of feedstocks. For example, corn does not grow in climates where the annual number of [degree] days above 40° F. is less than 240. In these cooler areas, the choice of feedstocks is limited, and there might not be any feedstocks available with AX/NSP close to 0.39. In these climates, improving such a feedstock by selectively breeding to increase its AX/NSP over a starting feedstock material would improve the efficiency of a cellulose-to-ethanol plant significantly, even if the AX/NSP still remained below 0.39. In these situations, the present invention would provide a novel standard against which such selectively bred feedstocks could be measured and compared. The desired extent of pretreatment might be achieved by any means available, including but not limited to those discussed in the preferred embodiments or examples contained herein. Any combination of mechanical and chemical treatments that results in the chemical changes noted lies within the scope of practicing the invention. This includes any reactors, chemicals added, temperature, time, particle size, moisture, and other parameters that result in the changes to the feedstock. In a first preferred embodiment, the pretreatment reaction is carried out at the broad conditions described by GRETHLEIN for acid pretreatments. This is done by subjecting the chosen feedstock to a temperature of about 180° C. to about 270° C., for a period of 5 seconds to 60 minutes. It is understood by those skilled in the art that the feedstock temperature is that of the feedstock itself, which might differ from the temperature measured outside the reaction chamber. It is also understood by those skilled in the art that a temperature range specified over a time period is the average temperature for that period, taking into account the effect of temperature on the rate of reaction. For example, the reaction chamber might require a short period to heat from ambient conditions up to 180° C. Based on knowledge of reaction kinetics (for example, within limited temperature ranges for a given substance, the rate approximately doubles over a 10° C. increase in temperature), the effect of the temperature increase on the overall reaction can be calculated and thereby the average temperature determined. The pretreatment reaction is typically run with 0.1% to 2% sulfuric acid present in the hydrolysis slurry. However, those skilled in the art are aware that alkali or acid present in some feedstocks can alter the acid requirement to be outside of the typical range. The degree of acidity present is better expressed by the target pH range, which is 0.5 to 2.5 regardless of the acid or concentration used. EXAMPLE 8 illustrates pretreatment reactions at this range of conditions. A second preferred embodiment uses the narrower set of conditions identified by FOODY as optimal for steam explosion pretreatment. This is illustrated in EXAMPLE 4 with pretreatment consisting of a cooking step at a temperature between 220° C. to 270° C. at pH 0.5 to 2.5 for 5 seconds to 120 seconds. Devices used to carry out this pretreatment preferably include sealed batch reactors and continuous extruders. Large scale examples of these pretreatment conditions are described in EXAMPLES 6 and 7. A third preferred embodiment uses a two-stage pretreatment, whereby the first stage improves the cellulose hydrolysis somewhat while solubilizing primarily the hemicellulose but little cellulose. The second stage then completes a full pretreatment. In this embodiment, the first stage reaction is run at a temperature of less than 180° C. while the second stage reaction is run at a temperature of greater than 180° C. An advantage of a two-stage pretreatment, as shown hereafter in EXAMPLE 5, is that a separate recovery of the hemicellulose for downstream processing is facilitated. In the third preferred embodiment, the first stage of reaction is carried out at a temperature of about 60° C. to about 140° C. for 0.25 to 24 hours at pH 0.5 to 2.5. More preferably, the first stage of pretreatment is carried out at a temperature of 100° C. to 130° C. for 0.5 to 3 hours at pH 0.5 to 2.5. In the fourth preferred embodiment, the second stage of reaction is carried out at a temperature of 180° C. to 270° C., at pH 0.5 to 2.5 for a period of 5 seconds to 120 seconds. The feedstock also can be dry (free from added moisture) or in a slurry with water. Another aspect to successful practice of the present invention is to integrate the pretreatment process within a process that hydrolyzes the pretreated feedstock with cellulase enzymes to produce glucose. In a preferred embodiment, at least 40% of the cellulose in the pretreated feedstock is hydrolyzed by cellulase enzymes to produce glucose. The glucose produced can be purified, crystallized, and packaged as solid sugar. Alternatively, it can be left dissolved in a liquid slurry for further processing or use. EXAMPLE 1: MEASUREMENT OF AX/NSP IN FEEDSTOCKS The ratio of arabinan plus xylan to total non-starch polysaccharides of a given feedstock was determined based on a compositional analysis of the feedstocks. This analysis was performed, as follows. Feedstocks examined were barley straw, wheat straw, wheat chaff, oat hulls, switch grass, corn stover, maple wood, pine wood, and three varieties of corn cobs. All were obtained locally in Ottawa, Ontario except the oat hulls, which were from Quaker Oats in Peterborough, Ontario. The feedstocks were coarsely ground in a Waring blender and then milled through a #20 gauge screen using a Wiley mill. The feedstocks were stored at ambient temperature in sealed bags until the time of use. The moisture content of small samples was 5% to 10% and was determined by drying at 100° C. Approximately 0.3 grams of sample was weighed into test tubes, each containing 5 ml of 70% sulfuric acid. The tubes were vortex mixed, capped, and placed in a 50° C. water bath for one hour, with vigorous vortex mixing every 10 minutes. After the one hour incubation, the tube contents were transferred into preweighed 250 ml flasks containing 195 ml deionized water, which reduced the acid content to 1.75%. The contents were mixed, and then 10 gram aliquots were transferred into test tubes. The tubes were vortex mixed and then transferred to a steam autoclave, where they were maintained for 1 hour at 121° C. After autoclaving, the solution contents were neutralized using a small amount of barium carbonate, and then vacuum-filtered over glass microfiber filter paper. The concentrations of glucose, xylose, and arabinose present in the filtrates were measured by using a Dionex Pulse-Amperometric HPLC. These measurements were then related to the weight of the initial sample of feedstock present and expressed as glucan, xylan, and arabinan contents, respectively, of the feedstock, with small adjustments to take into account (1) the water of hydration to make the monomers from polymers and (2) the amount of material destroyed by the concentrated acid, which was measured by taking pure cellulose, xylose, and arabinose controls through the procedure. The determination was performed in triplicate and the average value is reported. The cellulose content was determined by subtracting the starch content from the total glucan. The starch content was determined by adding 1 gram of Wiley-milled feedstock to a 250 ml flask containing 20 ml of deionized water, 0.2 ml of 91.7 g/L CaCl 2 ·2H 2 O stock solution, and 50 microliters of a 1:100 solution of Sigma Alpha Amylase #A3403 in deionized water. Each flask was adjusted to pH 6.4 to 6.6 using dilute sodium hydroxide, then incubated in a boiling water bath for one hour. The flasks were incubated for 30 minutes in a steam autoclave at 121° C. after the addition of a second 50 ml dose of amylase. Finally, the flask was incubated for another 60 minutes in the boiling water bath with a third 50 ml dose of amylase. The flasks were then cooled to ambient temperature and adjusted to pH 4.2 to 4.4 using dilute hydrochloric acid. A 0.5 ml aliquot of Novo Spritamylase stock solution was added; the stock solution consisted of 3 grams of enzyme in 100 ml deionized water. The flasks were shaken at 50° C. for 20 hours with 150 RPM agitation. The flasks were then cooled and the contents were filtered over glass microfiber filter paper. The glucose concentration was then measured on a Yellow Springs Instrument (YSI) glucose analyzer and used to determine the starch concentration of the feedstock, taking into account the water necessary to hydrolyze the starch. The protein and ash content of the feedstocks were determined by standard Kjeldahl nitrogen and ash oven methods. The lignin content of the samples was determined by measuring the amount of insoluble solids remaining after the sulfuric acid treatment of the feedstocks, then subtracting the amount of ash present. The results of these measurements are shown in TABLE 1. The material recovered was between 842 and 1019 mg per gram of original solids (mg/g). This corresponds to 84.2%, by weight, to 101.9% of the starting material, which is typical mass balance closure in these systems. TABLE 1__________________________________________________________________________COMPOSITION OF THE FEEDSTOCKSMeasured composition (mg/g) Arab-FeedstockGlucan Starch Xylan inan Lignin Ash Protein Total__________________________________________________________________________Barley426 19.6 161 28 168 82 64 929StrawWheat464 8.6 165 25 204 83 64 1005StrawWheat405 14.4 200 36 160 121 33 955chaffSwitch403 3.4 184 38 183 48 54 910grassCorn 411 3.2 128 35 127 60 81 842stoverMaple504 4.0 150 5 276 6 6 947woodPine 649 1.0 33 14 320 0 2 1018woodCorn cobs436 34 253 38 ND (2) ND ND ND(red)Corn cobs439 28 250 38 ND ND ND ND(white)Corn cobs438 8.5 240 36 ND ND ND ND(Indian)Oat Hulls481 89 247 39 170 44 38 1019__________________________________________________________________________ (1) Total = Glucan + Xylan + Arabinan + Lignin + Ash + Protein (2) ND = Not determined The AX/NSP content of the feedstocks is shown in TABLE 2. Of the 11 feedstocks analyzed, four have AX/NSP of greater than about 0.39. These include the samples of oat hulls and corn. The other seven feedstocks have AX/NSP content below about 0.39. TABLE 2______________________________________AX/NSP COMPOSITION OF THE FEEDSTOCKS Cellulose AX NSP (mg/g) (mg/g) (mg/g)Feed-stock (1) (2) (3) AX/NSP______________________________________Barley 407 189 596 0.317StrawWheat 455 190 645 0.295StrawWheat 391 236 627 0.376chaffSwitch 399 222 621 0.357grassCorn 408 163 571 0.285stoverMaple 500 155 655 0.237woodPine 648 47 695 0.068woodCorn cobs 402 291 693 0.420(red)Corn cobs 411 288 699 0.412(white)Corn cobs 429 276 705 0.391(Indian)Oat Hulls 392 286 678 0.422______________________________________ (1) Cellulose = Glucan - Starch (2) AX = Xylan + Arabinan (3) NSP = Xylan + Arabinan + Cellulose EXAMPLE 2: MEASUREMENT OF CELLULASE ACTIVITY OF AN ENZYME The cellulase activity of an enzyme is measured using the procedures of Ghose, PURE AND APPL. CHEM., 59:257-268 (1987), as follows. A 50 mg piece of Whatman #1 filter paper is placed in each test tube with 1 ml of 50 mM sodium dtrate buffer, pH 4.8. The filter paper is rolled up and the test tube is vortex mixed to immerse the filter paper in the liquid. A dilution series of the enzyme is prepared with concentrations ranging between 1:200 and 1:1600 of the initial strength in 50 mM sodium citrate buffer, pH 4.8. The dilute enzyme stocks and the substrates are separately preheated to 50° C., then a 0.5 ml aliquot of each dilute enzyme stock is placed in a test tube with substrate. The test tubes are incubated for 60 minutes at 50° C. The reaction is terminated by adding 3 ml of dinitrosalicyclic acid (DNS) reagent to each tube and then boiling for 10 minutes. Rochelle salts and deionized water were added to each tube to develop the color characteristic of the reaction between reducing sugars and DNS reagent. The amount of sugar produced by each sample of enzyme is measured, taking into account the small background from the enzyme and the filter paper, by comparing the amount of sugar in each tube with that of known sugar standards brought through the reaction. A unit of filter paper activity is defined as the number of micromoles of sugar produced per minute. The activity is calculated using the amount of enzyme required to produce 2 mg of sugar. A sample of Iogen Cellulase was found to have 140 filter paper units per ml, as shown in TABLE 3. TABLE 3______________________________________FILTER PAPER ACTIVITY OF IOGEN CELLULASEAmount of enzyme (ml) Enzyme activityto make 2 mg sugar (FPU/ml)______________________________________0.00264 140.0______________________________________ EXAMPLE 3: MILD PRETREATMENT REACTION WITH THE FEEDSTOCKS This example illustrates the comparative performance of the feedstocks after a mild pretreatment reaction that primarily dissolves the hemicellulose. This pretreatment reaction by itself is not optimal, although it could be the first stage of a two-stage pretreatment reaction. This mild reaction illustrates the use of AX/NSP to characterize the suitability of a feedstock for ethanol production. Optimized pretreatment reactions are described in later examples. Samples of 4 grams of Wiley-milled feedstocks from EXAMPLE 1 were placed in 96 grams of 1% sulfuric acid (pH 0.6 to 0.9) in a 250 ml flask. The contents of the flasks were gently mixed, and then the flasks were placed in a steam autoclave at 121° C. for 1 hour. The flasks were then cooled and vacuum-filtered over glass microfiber filter paper. The glucose, xylose, and arabinose concentrations of selected filtrates were determined by neutralizing with barium carbonate and analyzing the samples using a Dionex Pulsed-Amperometric HPLC. The filter cakes were washed with tap water and air dried. The cellulose, xylan, and arabinan concentrations in the solids were determined by dissolution of aliquots in 70% sulfuric acid, as described in EXAMPLE 1. The effect of the reaction on the cellulose and hemicellulose levels in the selected feedstocks is shown in TABLE 4. In all cases, small amounts (less than 8%) of the cellulose is hydrolyzed, while more than 70% of the hemicellulose is hydrolyzed. TABLE 4______________________________________EFFECT OF 121° C. PRETREATMENTREACTION ON DIFFERENT FEEDSTOCKSDissolution (%)Feedstock Cellulose Hemicellulose______________________________________Barley straw 3.2 85Wheat straw 3.6 72Wheat chaff <2 75Switch grass 5.7 80Corn stover 4.3 82Maple wood <2 80Oat hulls 7.9 85______________________________________ All 11 pretreated feedstocks were subjected to cellulase enzyme hydrolysis as follows. A sample of the pretreated solids corresponding to 0.2 grams of cellulose was added to a 250 ml flask with 19.8 grams of 0.05 M sodium citrate buffer, pH 5.0. Iogen Cellulase (standardized to 140 FPU/ml) and Novozym 188 beta-glucosidase (1440 BGU/ml) were added to the flask in an amount corresponding to 9 FPU/gram cellulose and 125 BGU/gram cellulose. The small amount of glucose carried into the flask with the beta-glucosidase was taken into account. Each flask was placed on a New Brunswick gyratory shaker at 50° C. and shaken for 20 hours at 250 RPM. At the end of this period, the flask contents were filtered over glass micro fiber filter paper, and the glucose concentration in the filtrate was measured by a YSI glucose analyzer. The glucose concentration was related to the cellulose concentration of the pretreated feedstock to determine the cellulose conversion. FIG. 1 is a graph of cellulose conversion for certain feedstocks, as a function of AX/NSP, at an average temperature of 121° C., according to EXAMPLE 3. Surprisingly, as shown in FIG. 1, for this particular pretreatment reaction the cellulose conversion increases linearly with the AX/NSP of the initial feedstock. The four feedstocks with the highest AX/NSP (oat hulls and the three corn cobs) had the highest conversion to glucose. These results indicate that the higher the AX/NSP of the feedstock, the more suitable the feedstock will be for ethanol production after a given pretreatment. EXAMPLE 4: HIGH PERFORMANCE PRETREATMENT REACTION WITH THE FEEDSTOCKS This example illustrates the comparative performance of the feedstocks after a pretreatment reaction. This pretreatment reaction is at conditions that optimize performance in the subsequent cellulose hydrolysis. Samples of 0.28 grams of Wiley-milled feedstocks from EXAMPLE 1 were placed in 7 grams of 1% sulfuric acid (pH 0.6 to 0.9) in a sealed stainless steel "bomb" reactor. The capacity of the bomb reactor is 9 ml. For any one experiment, five bombs of identical contents were set up and the reaction products were combined to produce a pool of adequate quantity with which to work. The bombs were placed in a preheated 290° C. oil bath for 50 seconds, then removed and cooled by placing them in tap water. Thermocouple measurements showed that the temperature in the interior of the bomb reached 260° C. by the end of the heating period. The average equivalent temperature was 235° C. The contents of the bombs were removed by rinsing with tap water, and then vacuum-filtered over glass microfiber filter paper. The filter cakes were washed with tap water and air dried. The cellulose concentration in the solids was determined by dissolution of aliquots in 70% sulfuric acid, as described in EXAMPLE 1. The reacted feedstocks were subjected to hydrolysis by cellulase as follows. A sample of the reacted solids corresponding to 0.05 grams of cellulose was added to a 25 ml flask with 4.9 grams of 0.05 M sodium citrate buffer, pH 4.8. Iogen Cellulase (140 FPU/ml) and Novozym 188 beta-glucosidase (1440 BGU/ml) were added to the flask in an amount corresponding to 9 FPU/gram cellulose and 125 BGU/gram cellulose. The small amount of glucose carried into the flask with the beta-glucosidase was taken into account. Each flask was placed on an Orbit gyratory shaker at 50° C. and shaken for 20 hours at 250 RPM. At the end of this period, the contents of the flasks were filtered over glass microfiber filter paper, and the glucose concentration in the filtrate was measured by a Dionex Pulsed-Amperometric HPLC. The glucose concentration was related to the cellulose concentration in the pretreated feedstock to determine the cellulose conversion. FIG. 2 is a graph of cellulose conversion for certain feedstocks, as a function of AX/NSP, at an average temperature of 235° C., according to EXAMPLE 4. As with the 121° C. reaction, FIG. 2 shows a cellulose conversion that also increases linearly with the AX/NSP of the initial feedstock. The four feedstocks with the highest AX/NSP (oat hulls and the three corn cobs) had the highest level of cellulose conversion observed, with more than 65% of the cellulose hydrolyzed to glucose. These results demonstrate that the higher the AX/NSP of the feedstock, the more suitable the feedstock will be for ethanol production after a high performance pretreatment. TABLE 5 shows the amount of cellulase enzyme required to reach 80% conversion to glucose. The amount of enzyme required is a key factor in determining the feasibility of an ethanol production process. The data in TABLE 5, are derived from the results shown in FIG. 2 plus other data describing cellulose conversion as a function of cellulase dosage. The top four feedstocks, including oat hulls and corn cobs, require 23% to 68%, less cellulase enzyme to convert to cellulose to glucose than the next best feedstock: wheat chaff. The top four feedstocks have a great performance advantage over the other feedstocks tested. The top four feedstocks have AX/NSP greater than 0.39, while the other feedstocks have AX/NSP below this value. This data demonstrates that significantly less cellulase enzyme is required for feedstocks with AX/NSP above about 0.39. This lower enzyme requirement is a significant advantage in an ethanol production process. TABLE 5______________________________________CELLULASE ENZYME REQUIREMENTS Cellulase dosage (FPU/g) for 80% conversion inFeedstock 20 hr AX/NSP______________________________________Corn Cobs (Red) 6.6 0.420Corn cobs (White) 8.7 0.412Corn cobs (Indian) 15.6 0.391Oat hulls 16.3 0.422Wheat chaff 21.0 0.376Switch grass 27.1 0.357Barley straw 28.3 0.317Wheat straw 44.5 0.295Maple wood 45.5 0.237Corn stover 63.4 0.285______________________________________ EXAMPLE 5: TWO-STAGE PRETREATMENT REACTION OF OAT HULLS This example demonstrates the use of a two-stage pretreatment reaction of oat hulls, the first mild stage followed by a second harsher stage. For the first stage, samples of 4 grams of Wiley-milled feedstocks from EXAMPLE 1 were placed in 96 grams of 1% sulfuric acid (pH 0.6 to 0.9) in a 250 ml flask. The contents of the flasks were gently mixed, and then the flasks were placed in a steam autoclave at 121° C. for 40 minutes. The flasks were then cooled and vacuum-filtered over glass microfiber filter paper. The glucose, xylose, and arabinose concentrations of the filtrates were determined by neutralizing with barium carbonate and analyzing the samples by using a Dionex Pulsed-Amperometric HPLC. The filter cakes were washed with tap water and air dried. The cellulose, xylan, and arabinan concentrations in the solids were determined by dissolution of aliquots in 70% sulfuric acid, as described in EXAMPLE 1. The effect of the mild reaction on the cellulose and hemicellulose (arabinan+xylan) levels in the feedstock is shown in TABLE 6. Almost all of the hemicellulose is dissolved, which enriches the concentration of cellulose. TABLE 6______________________________________COMPOSITION OF OAT HULLSAFTER MILD PRETREATMENT REACTIONFeedstock: Oat hulls Cellulose (%) Hemicellulose (%)______________________________________Before Pretreatment 27.9 22.0After Pretreatment 39.5 3.0______________________________________ Samples of 0.28 grams of feedstocks reacted under mild conditions were placed in 7 grams of 1% sulfuric acid (pH 0.6 to 0.9) in a sealed stainless steel "bomb" reactor as described in EXAMPLE 4. Five bombs of identical contents were set up and the reaction products were combined to produce a pool of adequate quantity with which to work. The bombs were placed in a preheated 290° C. oil bath for 50 seconds, then removed and cooled by placing them in tap water. The contents of the bombs were removed by rinsing with tap water, and then vacuum-filtered over glass microfiber filter paper. The filter cakes were washed with tap water and air dried. The cellulose concentration in the solids was determined by dissolution of aliquots in 70% sulfuric acid, as described in EXAMPLE 1. After one or two stages of pretreatment reaction, various feedstocks were subjected to hydrolysis by cellulase, as follows. A sample of the pretreated solids corresponding to 0.05 grams of cellulose was added to a 25 ml flask with 4.9 grams of 0.05 M sodium citrate buffer, pH 4.8. Iogen Cellulase (140 FPU/ml) and Novozym 188 beta-glucosidase (1440 BGU/ml) were added to the flask in an amount corresponding to 10 FPU/gram cellulose and 125 BGU per gram cellulose. The small amount of glucose carried into the flask with the beta-glucosidase was taken into account. Each flask was placed on an Orbit gyratory shaker at 50° C. and shaken for 20 hours at 250 RPM. At the end of this period, the contents of the flasks were filtered over glass microfiber filter paper, and the glucose concentration in the filtrate was measured by a Dionex Pulsed-Amperometric HPLC. The glucose concentration was related to the cellulose concentration in the pretreated feedstock to determine the glucose yield. The results are summarized in TABLE 7. After the first stage of reaction, little hemicellulose remained in the oat hulls. The glucose yield after the cellulose was hydrolyzed by cellulase was only 340 mg/g. After the second stage of pretreatment reaction, the glucose yield is over 85% higher than that of the first stage. The second stage pretreatment reaction therefore provided a significant enhancement of the hydrolysis performance. The two stage pretreatment results in a glucose yield within 6% of that after the single stage reaction of oat hulls described in EXAMPLE 4. These results ran exactly opposite to the teachings of Knappert, et al, who concluded that a material with low hemicellulose content does not have an improved digestibility by cellulase enzymes after pretreatment reaction. In the present example, after the first stage of reaction, very little hemicellulose remained in the oat hulls, yet the second stage reaction increased the digestibility significantly. Knappert et al taught that such a low-hemicellulose material should not respond well to pretreatment reaction. The present invention teaches the opposite. TABLE 7______________________________________TWO STAGE PRETREATMENT REACTION OF OAT HULLS HemicellulosePretreatment content before Glucose yieldreaction this stage (%) (mg/g cellulose)______________________________________Two stage 3.0 645First stage 22.0 340Single stage 22.0 685(EXAMPLE 4)______________________________________ EXAMPLE 6: LARGE SCALE PRETREATMENT REACTION WITH OAT HULLS A large scale pretreatment of oat hulls was carried out using a Werner-Pflederer twin-screw extruder (Ramsey, N.J.). After milling in a Wiley mill, the oat hulls were slurried to a 30% solids concentration in 1% sulfuric acid (pH 0.7 to 1.2). The slurry was fed to the extruder at a rate of 10 pounds per hour and the pressure was 500 psig. The extruder was maintained at 230° C. with live steam injection. At the average feed rate, the material passed through the extruder within 30 seconds. The extruded oat hulls were collected and washed with water to remove dissolved material, then filtered over glass microfiber filter paper. The cellulose content of the extruded oat hulls was measured using the methods of EXAMPLE 1. The extruded oat hulls were subjected to hydrolysis by cellulase as follows. A sample of the extruded oat hulls corresponding to 0.05 grams of cellulose was added to a 25 ml flask with 4.9 grams of 0.05 M sodium citrate buffer, pH 4.8. Iogen Cellulase (140 FPU/ml) and Novozym 188 beta-glucosidase (1440 BGU/ml) were added to the flask in an amount corresponding to 9 FPU/gram cellulose and 125 BGU/gram cellulose. The small amount of glucose carried into the flask with the beta-glucosidase was taken into account. Each flask was placed on an Orbit gyratory shaker at 50° C. and shaken for 20 hours at 250 RPM. At the end of this period, the contents of the flask were filtered over glass microfiber filter paper, and the glucose concentration in the filtrate was measured by a Dionex Pulse-Amperometric HPLC. The glucose concentration was related to the cellulose concentration of the extruded oat hulls to determine the glucose yield. The results are listed in TABLE 8. The glucose yield from the large scale pretreatment reaction of oat hulls was slightly (8%) less than that from the laboratory scale pretreatment in EXAMPLE 4. This indicates that the oat hull pretreatment reaction can be run on a large scale, as optimization of the extrusion operation will no doubt overcome the 8% advantage of the laboratory pretreatment reaction. TABLE 8______________________________________GLUCOSE YIELD FROM PRETREATED OAT HULLSPretreatment Glucose (mg/g cellulose)______________________________________Extruder 630Bomb (EXAMPLE 4) 685______________________________________ EXAMPLE 7: LARGE SCALE PRETREATMENT OF HARDWOOD A sample of aspen wood was pretreated using the steam explosion device and technique described by FOODY, U.S. Pat. No. 4,461,648. The resulting pretreated material was washed with water and is denoted as "Steam exploded hardwood". The cellulose content of the steam exploded hardwood was measured using the methods of EXAMPLE 1. The steam exploded hardwood was subjected to hydrolysis by cellulase enzyme as follows. A sample of the steam exploded hardwood corresponding to 0.05 grams of cellulose was added to a 25 ml flask with 4.9 grams of 0.05 molar sodium citrate buffer, pH 4.8. Iogen Cellulase (140 FPU/ml) and Novozym 188 beta-glucosidase (1440 BGU/ml) were added to the flask in an amount corresponding to 9 FPU/gram cellulose and 125 BGU/gram cellulose. The small amount of glucose carried into the flask with the beta-glucosidase was taken into account. Each flask was placed on an Orbit gyratory shaker at 50° C. and shaken for 20 hours at 250 RPM. At the end of this period, the contents of the flask were filtered over glass microfiber filter paper, and the glucose concentration in the filtrate was measured by a Dionex Pulsed-Amperometric HPLC. The glucose concentration was related to the cellulose concentration of the steam exploded hardwood to determine the glucose yield. The results are listed in TABLE 9. The performance of the hardwood reacted using the large scale device is within 2%, by weight, of that using the laboratory device. In this case, the large scale use of steam explosion has been extensively optimized and can match the laboratory results. TABLE 9______________________________________PRETREATMENT REACTION OF HARDWOODDevice Glucose yield (mg/g cellulose)______________________________________Steam explosion 415Laboratory (EXAMPLE 4) 425______________________________________ EXAMPLE 8: EFFECT OF TEMPERATURE ON SINGLE-STAGE AND TWO-STAGE PRETREATMENT REACTION OF OAT HULLS This example demonstrates the use of a range of temperatures with both single stage and two-stage pretreatment reactions of oat hulls. For the single stage reactions, samples of 0.28 grams of oat hulls were placed in 7 grams of 1% sulfuric acid (pH 0.6) in a sealed stainless steel "bomb" reactor as described in EXAMPLE 4. Five bombs of identical contents were set up and the reaction products combined to produce a pool of adequate quantity with which to work. The bombs were placed in a preheated oil bath, then removed and cooled by placing them in tap water. The temperatures and times in the oil bath were, as follows: (1) 235° C., 50 seconds; (2) 180° C., 6 minutes; (3) 170° C., 8 minutes. The contents of the bombs were removed by rinsing with tap water, and then vacuum-filtered over glass microfiber filter paper. The filter cakes were washed with tap water and air dried. The cellulose concentration in the solids was determined by dissolution of aliquots in 70% sulfuric acid, as described in EXAMPLE 1. For the two stage reactions, the first stage was carried out by placing samples of 4 grams of Wiley-milled oat hulls in 96 grams of 1% sulfuric add (pH 0.6) in a 250 ml flask. The contents of the flasks were gently mixed, and then the flasks were placed in a steam autoclave at 121° C. for 40 minutes. The flasks were then cooled and the contents were vacuum-filtered over glass microfiber filter paper. The filter cakes were washed with tap water and air dried. The cellulose, xylan, and arabinan concentrations in the solids were determined by dissolution of aliquots in 70% sulfuric acid, as described in EXAMPLE 1. The second stage was carried out by placing samples of 0.28 grams of material from the first stage in 7 grams of 1% sulfuric acid (pH 0.6) in a sealed stainless steel "bomb" reactor as described in EXAMPLE 4. Five bombs of identical contents were set up and the reaction products combined to produce a pool of adequate quantity to work with. The bombs were placed in a preheated oil bath, then removed and cooled by placing them in tap water. The temperatures and times in the oil bath matched those for the single stage reaction: (1) 235° C., 50 seconds; (2) 180° C., 6 minutes; (3) 170° C., 8 minutes. The contents of the bombs were removed by rinsing with tap water, and then vacuum-filtered over glass microfiber filter paper. The filter cakes were washed with tap water and air dried. The cellulose concentration in the solids was determined by dissolution of aliquots in 70% sulfuric acid, as described in EXAMPLE 1. Feedstocks after one or two stages of reaction were subjected to cellulase enzyme hydrolysis as follows. A sample of the reacted solids corresponding to 0.05 grams of cellulose was added to a 25 ml flask with 4.9 grams of 0.05 molar sodium citrate buffer, pH 4.8. IOGEN Cellulase (140 FPU/ml) and NOVOZYM 188 beta-glucosidase (1440 BGU/ml) were added to the flask in an amount corresponding to 9 FPU/gram cellulose and 125 BGU per gram cellulose. The small amount of glucose carried into the flask with the beta-glucosidase was taken into account. Each flask was placed on an Orbit gyratory shaker at 50° C. and shaken for 20 hours at 250 RPM. At the end of this period, the contents of the flasks were filtered over glass microfiber filter paper, and the glucose concentration in the filtrate was measured by a Dionex Pulsed-Amperometric HPLC. The glucose concentration was related to the cellulose concentration in the pretreated feedstock to determine the glucose yield. The results are summarized in TABLE 10. Using a single stage reaction, the glucose yield is almost as high at 180° C. as at the optimum temperature. The glucose yield drops as the temperature is decreased from 180° C. to 170° C. The two stage reaction has the same temperature profile as the single stage pretreatment reaction, with a similar performance at 180° C. and the optimum temperature, and a drop in performance below 180° C. Glucose yields in the two-stage reaction were 15% below those with the single stage reaction. TABLE 10______________________________________EFFECT OF TEMPERATURE ONGLUCOSE YIELD FROM OAT HULLS Glucose Reaction Reaction yield Relative Temperature Time (mg/g GlucosePretreatment (C.) (sec) cellulose) yield______________________________________Single stage 235 50 685 100Single stage 180 360 660 96Single stage 170 480 555 81Two stages 235* 50 575 84Two stages 180* 360 560 82Two stages 170* 480 485 71______________________________________ *Following a first stage at 121° C. While preferred embodiments of our invention have been shown and described, the invention is to be defined solely by the scope of the appended claims, including any equivalent for each recited claim element that would occur to one of ordinary skill and would not be precluded by prior art considerations.

An improved pretreatment of cellulosic feedstocks, to enable economical ethanol production by enzyme treatment. The improved pretreatment comprises choosing either a feedstock with a ratio of arabinoxylan to total nonstarch polysaccharides (AX/NSP) of greater than about 0.39, or a selectively bred feedstock on the basis of an increased ratio of AX/NSP over a starting feedstock material, and reacting at conditions that disrupt the fiber structure and hydrolyze a portion of the cellulose and hemicellulose. This pretreatment produces a superior substrate for enzymatic hydrolysis, by enabling the production of more glucose with less cellulose enzyme than any known procedures. This pretreatment is uniquely suited to ethanol production. Preferred feedstocks with an AX/NSP level greater than about 0.39 include varieties of oat hulls and corn cobs.

TECHNICAL FIELD [0001] The present invention generally relates to measurement of the distance of a shaft from the bottom of a vessel and the amount by which the shaft is offset from the center of the vessel. More particularly, the present invention relates to the precise measurement of shaft height and shaft offset in vessels employed in dissolution testing systems. BACKGROUND ART [0002] In the pharmaceutical industry, dissolution testing and analysis is required to be performed on samples taken from batches of tablets or capsules manufactured by pharmaceutical companies in order to assess efficacy and other properties. Dissolution analysis by automated means has become popular for increasing throughput and improving accuracy, precision, reliability, and reproducibility. Automation also relieves the tedium of manually performing a variety of requisite procedures, including: handling and delivering dosage units such as capsules and tablets; monitoring dissolution system parameters; manipulating the shafts carrying the agitation paddles or sample baskets; recording, displaying and printing accumulated data and test results; and cleaning and filtering the vessels employed in such procedures. [0003] Despite the benefits accruing from automation, validation of the procedures employed in dissolution testing and analysis remains a critical consideration. A typical dissolution test requires, among other things, that a rotatable shaft equipped with a paddle or basket be properly positioned in the center of, and properly located a specified distance from the bottom of, a dissolution test vessel prior to conducting the test. The USP has promulgated guidelines for the pharmaceutical industry which are enforced by the FDA. Under USP 24, General Chapters, Dissolution ( 711 ), the shaft must be positioned such that its centerline is not more than 2 mm at any point from the vertical axis of the vessel, and such that the paddle or basket (typically mounted to the lower end of the shaft) be positioned at 25 mm ±2 mm from the bottom of the vessel. [0004] Various hand-held devices have been utilized to carry out the measurements required to determine whether a shaft is positioned in a dissolution test vessel in compliance with the above-cited guidelines. Rulers, machinist calipers and micrometers, and pass/fail fixtures typify such devices and are known to persons skilled in the art. It is readily apparent to such skilled persons that operation of these devices requires a great deal of manual handling, with critical specifications largely determined by sight and feel. Conventional shaft measurement devices therefore engender an unacceptably high risk of error. There accordingly exists a long felt need for improved apparatus and methods for determining the position of a shaft installed in the vessel of a dissolution testing station. DISCLOSURE OF THE INVENTION [0005] In accordance with the present invention, an apparatus is mountable to a shaft disposed within a vessel and is adapted for measuring the magnitude by which the centerline of the shaft is offset from the central axis of the vessel. The apparatus comprises a housing and a plunger slidably mounted to the housing. The plunger has an outer section extending radially outwardly beyond a wall of the housing, and means such as a spring for biasing the plunger radially outwardly. A transducer is operatively mounted to the housing. The transducer is adapted to encode positions of the plunger and to produce an electrical signal proportional to a change in position resulting from displacement of the plunger. Means such as data lines are provided for transferring the signal to means such as a microprocessor for interpreting the signal. [0006] In another embodiment according to the present invention, an apparatus is mountable to a shaft having a paddle or basket disposed within a vessel. The vessel has a central axis and a hemispherical end region. The apparatus is adapted for measuring the distance from a distal surface of the paddle or basket to a lowermost point on the inside surface of the hemispherical end region. The apparatus comprises a housing and a plunger slidably mounted to the housing. The plunger has an outer section extending outwardly beyond a wall of the housing, and means such as a spring for biasing the plunger outwardly. An end portion extends transversely from the plunger beneath the housing and is substantially centered about a central portion of the housing. A transducer is operatively mounted to the housing. The transducer is adapted to encode positions of the plunger and to produce an electrical signal proportional to a change in position resulting from displacement of the plunger. Means such as data lines are provided for transferring the signal to means such as a microprocessor for interpreting the signal. [0007] In another embodiment according to the present invention, a system is provided for determining the location of a rotatable shaft in relation to a vessel mounted to a rack of a dissolution testing station. The shaft has a first end mounted to the testing station above the vessel, a second end disposed within the vessel and an operative component secured to the second end. The system comprises a housing including means such as a resilient clip and groove for removably mounting the housing to the shaft, and a plunger slidably mounted to the housing. The plunger has an outer section extending radially outwardly beyond a wall of the housing and extendable to an inside lateral surface of the vessel, and has means such as a spring for biasing the plunger radially outwardly. A transducer is operatively mounted to the housing. The transducer is adapted to encode positions of the plunger, and to produce an electrical signal proportional to a distance from a reference position to an extended position at which the plunger is in contact with the inside lateral surface of the vessel. Means such as data lines are provided for transferring the signal to means such as a microprocessor for interpreting the signal. [0008] In another embodiment according to the present invention, a system is provided for determining the location of a rotatable shaft in relation to a vessel. The vessel has a central axis and a hemispherical end region, and is mounted to a rack of a dissolution testing station. The shaft has a first end mounted to the testing station above the vessel, a second end disposed within the vessel and an operative component such as a paddle or basket secured to the second end. The system comprises a spherical object removably disposed in a lowermost point on an inside surface of the hemispherical end region of the vessel. A housing includes means such as a resilient clip or groove for removably mounting the housing to the shaft. A plunger is slidably mounted to the housing. The plunger has an outer section extending beyond a wall of the housing and extendable to the spherical object, and has means such as a spring for biasing the plunger outwardly. An end portion has an upper surface and a lower surface, and extends transversely from the plunger and between the operative component and the spherical object. [0009] A transducer is operatively mounted to the housing. The transducer is adapted to encode positions of the plunger, and to produce an electrical signal proportional to a distance from a reference position at which the top surface of the end portion of the plunger is biased against the operative component to an extended position at which the lower surface is in contact with the spherical object. Means such as data lines are provided for transferring the signal to means such as a microprocessor for interpreting the signal. [0010] In another object according to the present invention, a system is provided for determining the location of a shaft in relation to a vessel in which the shaft is disposed. The vessel has a central axis and a hemispherical end region. The system comprises a shaft offset measurement device which includes a first housing and a first plunger slidably mounted to the first housing. The first plunger has an outer section extending radially outwardly beyond a wall of the first housing and means such as a spring for biasing the first plunger radially outwardly. A first transducer is operatively mounted to the first housing. The first transducer is adapted to encode positions of the first plunger and to produce a first electrical signal proportional to a change in position resulting from displacement of the first plunger. [0011] The system further comprises a shaft height measurement device which includes a second housing and a second plunger slidably mounted to the second housing. The second plunger has an outer section extending outwardly beyond a wall of the second housing, and means such as a spring for biasing the second plunger outwardly. An end portion extends transversely from the second plunger beneath the second housing and is substantially centered about a central portion of the second housing. A second transducer is operatively mounted to the second housing. The second transducer is adapted to encode positions of the second plunger and to produce a second electrical signal proportional to a change in position resulting from displacement of the second plunger. [0012] The system further comprises a console including logic means such as a microprocessor for effecting interpretations of the first and second electrical signals and means such as an LCD display for displaying the interpretations in human-readable form. Means such as data lines are provided for transferring the first and second electrical signals to the logic means. [0013] In another embodiment according to the present invention, an apparatus is adapted for measuring the magnitude by which the centerline of a shaft is offset from the central axis of a vessel in which the shaft is disposed, and for measuring the distance from a distal end of the shaft to the lowermost point on an inside surface of a hemispherical end region of the vessel. The apparatus comprises a mounting assembly, a lateral plunger slidably mounted to the mounting assembly, a lateral transducer operatively disposed with respect to the mounting assembly and to the lateral plunger, a vertical plunger slidably mounted to the mounting assembly, and a vertical transducer operatively disposed with respect to the mounting assembly and to the vertical plunger. [0014] The lateral plunger has means such as a spring for biasing the lateral plunger radially outwardly. The lateral transducer is adapted to encode positions of the lateral plunger and to produce an electrical signal proportional to a change in position resulting from displacement of the lateral plunger. The vertical plunger has means such as a spring for biasing the vertical plunger downwardly with respect to the mounting assembly, and includes an upper end portion extending transversely from the vertical plunger. The vertical transducer is adapted to encode positions of the vertical plunger and to produce an electrical signal proportional to a change in position resulting from displacement of the vertical plunger. Means such as data lines are provided for transferring the signals produced respectively by the lateral and vertical transducers to means for interpreting the signals. The signal interpreting means can include a console with which the signal transferring means communicates, wherein the console has logic means such as a microprocessor for effecting interpretations of the signals and means such as an LCD display for displaying the interpretations in human-readable form. [0015] The present invention also provides methods for determining the position of a shaft installed in a vessel with respect to the central axis of the vessel and/or lowermost point inside the vessel. [0016] Accordingly, a method is provided for measuring the amount by which the centerline of a shaft is offset from the central axis of a vessel in which the shaft is to be disposed, comprising the following steps. A measurement device which includes a radially outwardly biased plunger is mounted to the shaft. The plunger has a settable zero reference position. The shaft is inserted into the vessel at a normal operating position of the shaft, wherein a distal end of the plunger is in contact with a lateral inside surface of the vessel at a first distal plunger position. A first displaced plunger position is defined as a position on the plunger located a distance by which the plunger has moved in relation to the zero reference position, the distance being equal a first displacement magnitude. [0017] The displacement magnitudes are measured by encoding the displaced plunger position and interpreting the displaced plunger position in relation to the zero reference position, wherein the displacement magnitudes determine the shaft centerline offset amount. A value for the shaft centerline offset amount is calculated based on the measured first displacement magnitudes. Finally, a signal is produced which is indicative of the shaft centerline offset amount. [0018] Accordingly, another method is provided wherein a distal end of the plunger position is in contact with a lateral inside surface of the vessel at a first distal plunger position. This first displaced plunger position is reset to the zero reference position. The shaft is then rotated one full revolution while continuously sampling the displacement of the plunger position is defined as a position on the plunger located a distance by which the plunger has moved in relation to the zero reference position, the distance being equal to the displacement magnitude from this continuous sampling, the lowest and the largest displacement magnitudes are kept. [0019] Another method according to the present invention is for measuring a shaft height, which is defined as the distance between the distal end of a shaft and the inside lowermost surface of a hemispherical end region of a vessel in which the shaft is to be disposed. The method comprises the following steps. A measurement device which includes a downwardly biased plunger is mounted to the shaft. The plunger includes an end portion. The end portion extends below the shaft and has a predetermined end portion height. A zero reference position of the plunger is defined by urging the end portion against the distal end of the shaft. The zero reference position is encoded. The inside lowermost surface of the hemispherical end region of the vessel is located by inserting a spherical object having a predetermined diameter into the vessel. The shaft is inserted into the vessel at a normal operating position of the shaft, permitting the end portion of the plunger to contact the spherical object. [0020] A displaced plunger position is defined as a position on the plunger located a distance by which the plunger has moved in relation to the zero reference position in order to contact the spherical object, the distance being equal to a displacement magnitude. The displacement magnitude is measured by encoding the displaced plunger position and interpreting the displaced plunger position in relation to the zero reference position, wherein the sum of a predetermined constant plus the displacement magnitude is proportional to the shaft height. A value for the shaft height is calculated based on the measured displacement magnitude. A signal is produced which is indicative of the shaft height. [0021] A further method according to the present invention is for measuring the amount by which the centerline of a shaft is offset from the central axis of a vessel in which the shaft is to be disposed, and for measuring a shaft height defined as the distance between the distal end of the shaft and the inside lowermost surface of a hemispherical end region of the vessel. The method comprises the following steps. The inside lowermost surface of the hemispherical end region of the vessel is located by inserting a spherical object into the vessel. A measurement device is mounted over the vessel. The measurement device includes a lateral plunger and a vertical plunger. The vertical plunger includes an end portion. The shaft is inserted into the vessel at a normal operating position of the shaft. [0022] A distal end of the lateral plunger is permitted to contact a lateral inside surface of the vessel. A displaced lateral plunger position is defined as a position on the lateral plunger located a lateral distance by which the lateral plunger has moved in relation to a predetermined zero reference position of the lateral plunger, the lateral distance being equal to a lateral displacement magnitude. The lateral displacement magnitude is measured by encoding the displaced lateral plunger position and interpreting the displaced lateral plunger position in relation to the zero reference position of the lateral plunger, wherein the lateral displacement magnitude determines the shaft centerline offset amount. A value for the shaft centerline offset amount is calculated based on the measured lateral displacement magnitude. A signal is produced which is indicative of the shaft centerline offset amount. [0023] The end portion of the vertical plunger is permitted to contact the spherical object. A displaced vertical plunger position is defined as a position on the vertical plunger located a vertical distance by which the vertical plunger has moved in relation to a predetermined zero reference position of the plunger, the vertical distance being equal to a vertical displacement magnitude. The vertical displacement magnitude is measured by encoding the displaced vertical plunger position and interpreting the displaced vertical plunger position in relation to the zero reference position of the vertical plunger, wherein the vertical displacement magnitude determines the shaft height. A value for the shaft height is calculated based on the measured vertical displacement magnitude. A signal is produced which is indicative of the shaft height. [0024] It is therefore an object of the present invention to provide an apparatus for measuring the amount by which the centerline of a shaft disposed in a vessel is offset from the central vertical axis of the vessel. [0025] It is another object of the present invention to provide an apparatus for measuring the height of such shaft above the lowermost inside point of the vessel. [0026] It is a further object of the present invention to provide an apparatus for controlling the process by which the shaft centerline offset amount and shaft height are measured, and for expressing the results of such process using peripheral devices. [0027] It is yet another object of the present invention to provide improved methods for determining accurate values for the shaft centerline offset amount and shaft height. [0028] Some of the objects of the invention having been stated hereinabove, other objects will become evident as the description proceeds, when taken in connection with the accompanying drawings as best described hereinbelow. BRIEF DESCRIPTION OF THE DRAWINGS [0029] [0029]FIG. 1 is a cross-sectional view of a paddle shaft installed in a vessel in which the present invention is implemented; [0030] [0030]FIG. 2 is a perspective view of a dissolution testing station in which the present invention is implemented; [0031] [0031]FIG. 3A is a perspective view of a shaft centerline offset and height measurement system according to the present invention; [0032] [0032]FIG. 3B is a perspective view of a shaft height measurement device according to the present invention; [0033] [0033]FIG. 3C is a perspective view of a shaft centerline offset measurement device according to the present invention; [0034] [0034]FIG. 4A is a front elevation view of the shaft centerline offset measurement device in FIG. 3C; [0035] [0035]FIG. 4B is a rear elevation view of the shaft centerline offset measurement device in FIG. 3C; [0036] [0036]FIG. 4C is a top plan view of the shaft centerline offset measurement device in FIG. 3C; [0037] [0037]FIG. 4D is a bottom plan view of the shaft centerline offset measurement device in FIG. 3C; [0038] [0038]FIG. 5A is a front elevation view of the shaft height measurement device in FIG. 3B; [0039] [0039]FIG. 5B is a rear elevation view of the shaft height measurement device in FIG. 3B; [0040] [0040]FIG. 5C is a top plan view of the shaft height measurement device in FIG. 3B; [0041] [0041]FIG. 5D is a bottom plan view of the shaft height measurement device in FIG. 3B; [0042] [0042]FIGS. 6A and 6B are front and rear elevation views, respectively, of a shaft centerline offset measurement device mounted to a shaft within a vessel according to the present invention; [0043] [0043]FIGS. 7A and 7B are front and rear elevation views, respectively, of a shaft height measurement device mounted to a shaft within a vessel according to the present invention; [0044] [0044]FIGS. 8A, 8B and 8 C are geometric views illustrating a method for calculating the offset amount of the centerline of a shaft according to the present invention; [0045] [0045]FIG. 9 is a geometric view illustrating another method for calculating the offset amount of the centerline of a shaft according to the present invention; [0046] [0046]FIGS. 10A and 10B are perspective views of a combined shaft centerline offset and height measurement device according to the present invention; [0047] [0047]FIGS. 11A and 11B are detailed perspective views of a shaft centerline offset measurement module of the device in FIGS. 10A and 10B; [0048] [0048]FIG. 12 is a detailed perspective view of a shaft height measurement module of the device in FIGS. 10A and 10B; and [0049] [0049]FIGS. 13A and 13B are a flow diagram of a test routine according to the present invention. DETAILED DESCRIPTION OF THE INVENTION [0050] [0050]FIG. 1 illustrates a typical vessel V employed in a dissolution testing station, while FIG. 2 illustrates one such testing station generally designated DTS. Vessel V has an open upper end 12 , a lateral side region 14 , and a hemispherical end region 16 . A plurality of vessels V (typically 6 or 8 ) are mounted in a rack 18 of dissolution testing station DTS for high-throughput testing. Each vessel V is centered and locked into position on rack 18 with the aid of a vessel centering ring CR (not shown in FIG. 2). Dissolution testing station DTS includes, among other components, a water bath WB for temperature control of vessels V and a programmable systems control module 20 having peripheral elements such as an LCD display 20 A, a keypad 20 B, and individual readouts 20 C. A shaft S provided with a paddle or basket P may be inserted into each vessel V. One or more spindle motors (not shown) housed within control module 20 drive the rotation of shafts S through a chuck (not shown) or equivalent coupling means. Referring specifically to FIG. 1, the parameters of shaft position relative to vessel V sought to be determined are shaft centerline offset determined by shaft distance x, and shaft or paddle height y. The present invention described in detail below has been found by applicants to measure these parameters accurately to within 0.1 mm. [0051] [0051]FIGS. 3A through 3C show a shaft centerline offset and height measurement system according to the present invention and generally designated 30 . Primary components of measurement system include a shaft centerline offset measurement device generally designated 40 , a height measurement device generally designated 50 , and a control/display console generally designated 60 . Control/display console 60 is portable and thus includes a handle 60 A. A keypad 60 B is provided for inputting commands, calibration data, and the like. Results derived from measurements taken by centerline offset and height measurement devices 40 , 50 are transferred through electrical conduits EC and may be displayed at display screen 60 C, which is preferably an LCD type display. Alternatively, these results may be sent through a communication port 60 D such as an RS 232 port to another peripheral such as a remote computer. Control/display console 60 can also be equipped with an on-board dot-matrix printer 60 E. In addition, control/display console 60 includes a decoder chip adapted for decoding signal received from transducers, a CPU for performing calculations and other computing functions, a memory register, and other associated logic components and circuitry (not shown). A suitable decoder chip is a quadrature decoder available from HEWLETT PACKARD as model designation HCTL-2016. A suitable CPU is a micro controller unit available from PHILLIPS as model designation 87C52. [0052] Centerline offset measurement device 40 is illustrated in more detail in FIGS. 3C and 4A through 4 D. Height measurement device 50 is illustrated in more detail in FIGS. 3B and 5A through 5 D. [0053] Referring particularly to FIGS. 3C and 4A, centerline offset measurement device 40 includes a housing 42 , a lateral plunger 44 , and a horizontally-oriented sensor or transducer 46 (indicated schematically in FIG. 4A by phantom lines). Preferably, both lateral plunger 44 and transducer 46 are mounted within housing 42 . Lateral plunger 44 is movably mounted to housing 42 by conventional means, such that lateral plunger 44 can slide inwardly and outwardly with respect to housing 42 . An outer section 44 A of lateral plunger 44 extends outside housing 42 through a hole 42 A in a wall 42 B of housing 42 . Means such as a spring (not shown) is provided to interface with lateral plunger 44 and housing 42 and to impart a biasing force to lateral plunger 44 in a radially outward direction away from housing 42 . Preferably, an arrow-shaped plunger head 44 B is provided at a distal end 44 C of lateral plunger 44 for a purpose described hereinbelow. Means such as an electrical conduit EC containing lead wires is provided for transferring signals generated by transducer 46 . [0054] Transducer 46 serves to measure a change in lateral position of lateral plunger 44 by converting a sense of the physical change in such position to an electronic signal representative of the magnitude of such change. For this purpose, transducer 46 is preferably an optical linear encoder module such as model designation HEDS 9200 R00 available from HEWLETT PACKARD. Transducer 46 operates in conjunction with a code strip (not shown) in a manner typical of optical encoders. Because transducer 46 is to measure positional changes of lateral plunger 44 , the code strip is mounted to an inner section 44 D of lateral plunger 44 in the vicinity of transducer 46 . Hence, as lateral plunger 44 moves, the code strip moves with respect to transducer 46 . As the code strip passes by transducer 46 , transducer 46 optically reads and counts lines on the code strip. The number of lines counted is correlated to a magnitude by which lateral plunger 44 has moved from an initial reference position. Alternatively, transducer 46 could be mounted to lateral plunger 44 and the code strip fixedly secured within housing 42 . [0055] Referring to FIGS. 3C, 4B and 4 C, a longitudinal recess 48 is formed in a rear face 42 C of housing 42 by a recess wall 48 A. Preferably, recess wall 48 A has a cylindrical profile to better accommodate the contour of shaft S. In an upper section 48 B of longitudinal recess 48 proximate to a top face 42 D of housing 42 , a clip-like member 49 is provided to assist the secure mounting of shaft centerline offset measurement device 40 to shaft S. Clip-like member 49 includes a pair of resilient prongs 49 A and 49 B. In addition, a bottom face 42 E of housing 42 may be configured to conform to the specific type of operative component, e.g., paddle or basket P, carried on shaft S in order to further assist in mounting thereto. Thus, in the exemplary embodiment shown in FIG. 4D, bottom face 42 E includes a groove 42 F that enables housing 42 to straddle paddle P when mounted to shaft S. FIGS. 6A and 6B show centerline offset measurement device 40 mounted to shaft S and shaft S installed in vessel V. [0056] Referring particularly to FIGS. 3B and 5A, height measurement device 50 includes a housing 52 , a vertical plunger 54 , and a vertically-oriented sensor or transducer 56 (indicated schematically in FIG. 5A by phantom lines). As in the case of centerline offset measurement device 40 , both vertical plunger 54 and transducer 56 are preferably mounted within housing 52 . Vertical plunger 54 is movably mounted to housing 52 by conventional means, such that vertical plunger 54 can slide inwardly and outwardly with respect to housing 52 . An outer section 54 A of vertical plunger 54 extends outside housing 52 through a hole 52 A in a wall 52 B of housing 52 . Means such as a spring (not shown) is provided to interface with vertical plunger 54 and housing 52 and to impart a biasing force to vertical plunger 54 in a downward direction away from housing 52 . An end portion 54 B is attached to vertical plunger 54 in offset relation thereto by means of an intermediate member 54 C. Accordingly, when height measurement device 50 is mounted to shaft S, vertical plunger 54 is situated in parallel relation to shaft S and end portion 54 B is centrally disposed beneath shaft S and its operative component P. The purpose of end portion 54 B is described hereinbelow. Finally, means such as an electrical conduit EC containing lead wires is provided for transferring signals generated by transducer 56 . [0057] In a manner analogous to that respecting centerline offset measurement device 40 , transducer 56 serves to measure a change in vertical position of vertical plunger 54 by converting a sense of the physical change in such position to an electronic signal representative of the magnitude of such change. Consequently, transducer 56 specified for height measurement device 50 is the same or similar unit as transducer 46 specified for centerline offset measurement device 40 , as well as the associated code strip which preferably is mounted to vertical plunger 54 . [0058] Referring to FIGS. 3B, 5B and 5 C, means are provided for mounting height measurement device 50 to shaft S similar to that respecting centerline offset measurement device 40 . That is, a longitudinal recess 58 is formed in a rear face 52 C of housing 52 by a cylindrically-profiled recess wall 58 A. A clip-like member 59 including a pair of resilient prongs 59 A and 59 B is disposed in an upper section 58 B of longitudinal recess 58 proximate to a top face 52 D of housing 52 . In addition, a bottom face 52 E of housing 52 includes a groove 52 F or other means for improving the securement of height measurement device 50 to shaft S provided with paddle P or the like, as shown in FIG. 5D. FIGS. 7A and 7B show height measurement device 50 mounted to shaft S and shaft S installed in vessel V. [0059] The operation of shaft centerline offset and height measurement system 30 will now be described with particular reference to FIGS. 3A, 6A, 6 B, 7 A, 7 B, 8 A through 8 C, and 9 . By way of example, an indication of centerline offset is obtained before an indication of shaft or paddle height is obtained. [0060] Referring to FIGS. 6A and 6B, the operation of centerline shaft measurement device 40 will first be described. Centerline offset measurement device 40 is affixed to shaft S. Shaft S is then lowered into vessel V at a normal operating position for shaft S. Because lateral plunger 44 is preferably biased radially outwardly, the tapered edges that comprise arrow-shaped plunger head 44 B assist in installing and removing shaft S from vessel V when centerline offset measurement device 40 is mounted to shaft S. After shaft S is disposed in its normal operating position, a distal end (which in the present exemplary embodiment corresponds to the outermost surface of plunger head 44 B) of outwardly biased lateral plunger 44 is in contact with a lateral inside surface ID of vessel V. [0061] At this point, assuming shaft S is offset from the true central vertical axis of vessel V, lateral plunger 44 will have displaced laterally with respect to a zero reference position. At this plunger position, lateral plunger 44 will have displaced a distance equal to a displacement magnitude. This displacement magnitude is evident by the change in position of the code strip mounted to lateral plunger 44 . Transducer 46 encodes the displaced position of the code strip, and thus the displaced position of lateral plunger 44 , and sends the encoded signal to control/display console 60 (see FIG. 3A), which decodes, stores, and processes the signal. [0062] The displacement magnitude measured is one indication of the amount by which shaft S is offset from the central axis of vessel V. This displacement magnitude alone, however, is not necessarily a good indication when one considers that the position of lateral plunger 44 will change when lateral plunger 44 is disposed at other distal plunger positions on the circumference of lateral inside surface ID of vessel V. Accordingly, more precision can be achieved by employing transducer 46 to sample a plurality of displaced plunger positions. These displaced plunger positions are obtained when lateral plunger 44 is rotated to define a plurality of distal plunger positions located on the circumference of lateral inside surface ID. By doing so, a calculation of the centerline offset amount can be based on a plurality of displacement magnitudes measured by transducer 46 at different circumferential locations on lateral inside surface ID. [0063] Referring to FIGS. 8A through 8C, lateral inside surface ID is assumed to be a perfect circle ABC for purposes of calculation and has a center O through which central axis of vessel V runs. The centerline of the shaft S is represented by a point T, thus illustrating that shaft S is clearly not in alignment with the central axis of vessel V. Shaft S with centerline offset measurement device 40 mounted thereto is inserted into vessel V as described above, at which time distal end or plunger head 44 B of lateral plunger 44 contacts lateral inside surface ID at a first distal plunger position A. The distance by which lateral plunger 44 is displaced at this time is encoded by transducer 46 and stored in control/display console 60 as a first displacement magnitude. After the first displacement magnitude is measured, second and third displacement magnitudes are likewise measured by respectively rotating lateral plunger 44 120° (or one-third of a revolution around lateral inside surface ID) to a second distal plunger position B and another 120° to a third distal plunger position C. [0064] Lateral plunger 44 can be rotated by manually rotating housing 42 around shaft S or by rotating shaft S itself. In order to aid in locating the 120° positions, indicator marks (not shown) could be provided, for instance, on vessel centering ring CR (see FIG. 1). Nevertheless, the method described herein will give an accurate indication of centerline offset even if readings are taken at plunger positions that deviate approximately ±5° from the 120° positions. [0065] Referring to FIG. 8A, a radial distance d 1 along lateral plunger 44 from centerline T to first distal plunger position A, a radial distance d 2 along lateral plunger 44 from centerline T to second distal plunger position B, and a radial distance d 3 along lateral plunger 44 from centerline T to third distal plunger position C are obtained. Radial distances d 1 , d 2 and d 3 can be derived in a variety of ways, such as by taking a value representing some constant plunger length and adjusting that value by taking into account the measured first, second and third displacement magnitudes, respectively. A chordal distance AB between first and second distal plunger positions A, B, a chordal distance AC between first and third distal plunger positions A, C and a chordal distance BC between second and third distal plunger positions B, C are then calculated respectively according to the following equations derived from the law of cosines: AB = ( d 1 ) 2 + ( d 2 ) 2 - 2 · d 1 · d 2 · cos  ( 2 · π 360 · 120 ) AC = ( d 1 ) 2 + ( d 3 ) 2 - 2 · d 1 · d 3 · cos  ( 2 · π 360 · 120 ) BE = ( d 3 ) 2 + ( d 2 ) 2 - 2 · d 3 · d 2 · cos  ( 2 · π 360 · 120 ) [0066] Next, a theoretical radius R for circle ABC based on chordal distances AB, AC, and BC is calculated according to the following equation: R = AB · AC · BC 4 · S · ( S - AB ) · ( S - AC ) · ( S - BC ) wherein     factor     S = AB + AC + BC 2 [0067] Referring to FIG. 8B, it follows that radius R is equal to a radius AO from center O to first distal plunger position A, a radius BO from center O to second distal plunger position B, and a radius CO from center O to third distal plunger position C. An angle AOB between radii AO and BO is then calculated according to the following equation derived from the law of cosines: AOB = cos - 1  ( ( AO ) 2 + ( BO ) 2 - ( AB ) 2 2 · AO · BO ) · 360 2 · π [0068] Referring to FIG. 8C, values for radial distances AT and BT are equal to radial distances d 1 and d 2, respectively. Thus, an angle ABT between radial distances AT and BT is calculated according to the following equation derived from the law of sines: ABT = sin - 1  ( d 1 · sin  ( 120 · 2 · π 360 ) AB ) · 360 2 · π [0069] Next, an angle ABO between chordal distance AB and radius BO and an angle OBT between radius BO and radial distance BT are calculated according to the following equations: ABO = 180 - AOB 2 OBT = ABT - ABO [0070] It will be seen from FIG. 8C that a triangle is defined by three vertices corresponding to center O, centerline T, and second distal plunger position B. Because the values for two sides of this triangle, radius BO and radial distance BT, and the angle OBT therebetween are known, control/display console 60 can now calculate the value for the remaining side, which is the offset distance OT of centerline T from center O. Offset distance OT is calculated according to the following equation derived from the law of cosines: OT = ( BO ) 2 + ( d 2 ) 2 - ( 2 · BO · d 2 · cos  ( OBT · 2 · π 360 ) ) [0071] The offset distance OT provides an accurate indication of the amount by which the centerline of shaft S is offset from the central axis of vessel V in any radial direction. This is because the calculation is based on three displacement magnitudes measured at three different positions of lateral plunger 44 within vessel V, and the relationships between the various points and distances observed within vessel V and described hereinabove can be resolved by trigonometric equations. [0072] A preferred modification to the method described above yields the same result, i.e., calculation of offset distance OT, yet avoids the additional task of deriving values for radial distances AT, BT and CT from the first, second and third displacement magnitudes. In this preferred modification, advantage is taken of the fact that the first, second and third displacement magnitudes measured by transducer 46 are linearly proportional to radial distances AT, BT and CT, respectively. Thus, radial distance d 1 is set equal to zero, radial distance d 2 is set equal to a value based on the second displacement magnitude relative to the first displacement magnitude, and radial distance d 3 is set equal to a value based on the third displacement magnitude relative to the first displacement magnitude. For example, d 1 =0, d 2 =−0.1, and d 3 =−0.9. If such values for d 1 , d 2 and d 3 are used and the above equations applied, the same value for offset distance OT is obtained. [0073] A further alternative method for calculating the amount by which the centerline of shaft S is offset from the central axis of vessel V will now be described with reference to FIG. 9. Lateral inside surface ID of vessel V is represented by a circle AB in FIG. 9, and has a center O through which the central axis of vessel V runs. The centerline of shaft S is represented by point T. If a diameter for circle AB is drawn through center O and centerline T, it is observed that a maximum displacement magnitude will be measured when lateral plunger 44 is disposed within vessel V along a maximum radial distance AT, and a minimum displacement magnitude will be measured when lateral plunger 44 is rotated 180° and disposed along a minimum radial distance BT. If lateral inside surface ID of vessel V were a perfect circle, an offset distance OT could be found by subtracting radius AO from radial distance AT or by subtracting radial distance BT from radius BO. A preferred method of calculation, however, is derived as follows. [0074] It is observed that maximum radial distance AT=AO+OT and minimum radial distance BT=BO−OT. For purposes of calculation, lateral inside surface ID of vessel V is assumed to be a perfect circle such that AO=BO. Thus, minimum radial distance BT=AO−OT. Offset distance OT can be found by subtracting maximum radial distance AT from minimum radial distance BT as follows: AT - BT = ( AO + OT ) - ( AO - OT ) = 2  OT Therefore ,  OT = ( AO + OT ) - ( AO - OT ) 2 = AT - BT 2 [0075] In order to implement this method, lateral plunger 44 is rotated 360°, i.e., one full revolution around the inside of vessel V. At predetermined intervals while lateral plunger 44 is rotating, e.g., every 5 ms, transducer 46 encodes the position of lateral plunger 44 to generate a data set consisting of a plurality of displacement magnitudes. From this data set, a maximum measured displacement magnitude d MAX and a minimum measured displacement magnitude d MIN are selected. An example of a subroutine that could perform this selection process can be constructed from the following steps: [0076] 1) READ a first displacement magnitude and STORE; [0077] 2) READ a second displacement magnitude and STORE; [0078] 3) IF second displacement magnitude<first displacement magnitude, THEN SET second displacement magnitude=d MIN AND SET first displacement magnitude=d MAX , ELSE SET second displacement magnitude=d MAX AND SET first displacement magnitude=d MIN ; [0079] 4) READ a third displacement magnitude; [0080] 5) IF third displacement magnitude<d MIN THEN SET third displacement magnitude=d MIN ; [0081] 6) IF third displacement magnitude>d MAX THEN SET third displacement magnitude=d MAX . [0082] This procedure is repeated successively until each sampled displacement magnitude is determined to be either the maximum or minimum for the data set. Offset distance OT is then calculated according to the following equation: OT = d MAX - d MIN 2 [0083] Referring primarily to FIGS. 7A and 7B, the operation of height measurement device 50 will now be described. Height measurement device 50 is affixed to shaft S. Prior to installation of shaft S in vessel V, a spherical object such as a stainless steel ball 65 having a predetermined uniform diameter is placed into vessel V. Stainless steel ball 65 will come to rest at a lowermost point 19 on the inside surface of hemispherical end region 16 of vessel V, thereby locating the true bottom of vessel V. Vertical plunger 54 is biased to a fully downwardly extended position. In order to obtain a zero reference position, end portion 54 B of vertical plunger 54 is urged upwardly until good contact is made with the underside of paddle P or other operative component of shaft S. Shaft S is then inserted into vessel V at a normal operating position for shaft S. [0084] Once shaft S has been installed, vertical plunger 54 moves downwardly until coming into contact with stainless steel ball 65 . At this point, vertical plunger 54 will have displaced vertically with respect to the zero reference position. The distance by which vertical plunger 54 displaces is characterized as its displacement magnitude. Transducer 56 encodes the displaced position by reading the code strip mounted to vertical plunger 54 and generates a signal representative of the measured displacement magnitude, in a manner analogous to the interaction of transducer 46 and the code strip of lateral plunger 44 of centerline offset measurement device 40 described hereinabove. Transducer 56 sends the encoded signal to control/display console 60 (see FIG. 3A). The height of paddle P above lowermost point 19 of hemispherical end region 16 is most easily derived from the measured displacement magnitude by adding together the values for the displacement magnitude, the height of end portion 54 B and the diameter of stainless steel ball 65 . [0085] As an alternative embodiment of the present invention, shaft centerline offset and height measurement system 30 can be modified to incorporate both the shaft centerline offset and height measurement functions in a single measurement device. That is, housing 42 or 52 can be adapted to accommodate both transducers 46 and 56 , plungers 44 and 54 , and their associated components described hereinabove. However, a preferred approach to this functional combination is to provide a more modular device which does not require the mounting of a single (and bulkier and heavier) housing to shaft S. [0086] This preferred alternative embodiment will now be described with reference to FIGS. 10A, 10B, 11 A, 11 B and 12 , illustrating a combined shaft centerline offset and height measurement device generally designated 70 . [0087] Instead of employing a housing to serve as a mounting assembly for centralizing the operative components of the present embodiment, a modified 10 vessel centering ring 75 is provided. Modified vessel centering ring 75 includes a central region 75 A having a bore 75 B through which shaft S with paddle P or the like can be inserted. [0088] Combined shaft centerline offset and height measurement device 70 includes a centerline offset measurement module generally designated 80 and a height measurement module generally designated 90 . It will be noted that all operative components of combined shaft centerline and offset measuring device 70 , including centerline offset measurement module 80 and a height measurement module 90 , are mounted directly or indirectly to modified vessel centering ring 75 , and thus operate independently of shaft S. Thus, while only one centerline offset measurement module 80 could be provided and rotated by means such as a turntable mounted to modified vessel centering ring 75 , it is more advantageous to provide three centerline offset measurement modules 80 , all of which are suspended from modified vessel centering ring 75 independently of shaft S. Moreover, as shown in FIGS. 10A and 10B, centerline offset measurement modules 80 are oriented 120° from each other, thereby eliminating the alignment and rotation steps attending centerline offset measurement device 40 in FIGS. 4A through 4D. [0089] Referring to FIGS. 11A and 11B, each centerline offset measuring module 80 includes a sensor body 82 which serves as a mounting bracket for a lateral plunger 84 and a transducer 86 . Sensor body 82 preferably has a U-shaped profile defined by a central region 82 A and legs 82 B and 82 C. Transducer 86 is preferably secured directly to the inside of leg 82 B of sensor body 82 , and preferably is an optical linear encoder similar to transducers 46 and 56 . An upper linear bearing 102 A is attached to a top surface 82 D of central region 82 A and a lower linear bearing 104 A is attached to an end 82 E of leg 82 C. A lower bearing track 104 B is attached to each lateral plunger 84 and engages lower linear bearing 104 A, thereby enabling lateral plunger 84 to slide laterally with respect to sensor body 82 . A code strip 106 is fixedly secured to lateral plunger 84 to cooperate with transducer 86 in the manner described hereinabove. [0090] As shown in FIG. 10B, three upper bearing tracks 102 B (of which only two are shown) are attached to central region 75 A of modified vessel centering ring 75 . Upper linear bearing 102 A of each sensor body 82 engages a corresponding upper bearing track 102 B to enable each sensor body 82 to slide laterally with respect to modified vessel centering ring 75 . In the exemplary embodiment shown in FIGS. 10A and 10B, means such as springs (not shown) are provided respectively for biasing each lateral plunger 84 radially inwardly and for biasing each sensor body 82 radially outwardly. Thus, when shaft S is installed into vessel V, plunger tips 84 A of lateral plungers 84 are biased to contact shaft S while rear faces 82 F of sensor bodies 82 are biased to contact lateral inside surface ID of vessel V. Each lateral plunger 84 has upper and lower guide members 84 B and 84 C, respectively, to assist in urging lateral plungers 84 outwardly when shaft S is being inserted and removed from vessel V. [0091] [0091]FIG. 12 is a detailed view of height measurement module 90 , which is an alternative to incorporating the structure of height measurement device 50 described hereinabove. Height measurement module 90 includes a sensor mounting bracket 92 , a vertical plunger 94 , and a vertically-oriented transducer 96 . Vertical plunger 94 preferably includes a vertical rail 94 A, an upper arm 94 B, and a lower arm 94 C. Sensor mounting bracket 92 includes a clamping section 92 A by which sensor mounting bracket 92 is fixedly secured to vertical rail 94 A, such as by inserting vertical rail 94 A through clamping section 92 A and tightening clamping section 92 A with a fastener (not shown) threaded into holes 92 B. [0092] In the preferred embodiment, lower arm 94 C includes an arcuate section 94 CA and a lower end portion 94 CW extending horizontally from arcuate section 94 CA. Likewise, upper arm 94 B includes an arcuate section 94 BA and a lower end portion 94 BB extending horizontally from arcuate section 94 BA. Arcuate sections 94 BA and 94 CA are disposed adjacent to each other, and upper end portion 94 BB is disposed above lower end portion 94 CB. Means such as a spring 98 is connected between upper end portion 94 BB and lower end portion 94 CB in order to vertically bias upper and lower end 94 BB and 94 CB portions away from each other. [0093] Lower arm 94 C is secured to sensor mounting bracket 92 , or preferably is secured directly to vertical arm 94 A such as by inserting vertical arm 94 A into an upper portion of lower arm 94 CC and employing fastening means similar to clamping section 92 A. Upper arm 94 B is mounted to an annular bearing 99 through which vertical rail 94 A extends, thus enabling upper arm 94 B to move vertically with respect to lower arm 94 C and transducer 96 . Vertical rail 94 A is provided with a longitudinal groove 94 A' which engages a complementary tongue (not shown) disposed within annular bearing 99 , thereby preventing annular bearing 99 and upper arm 94 B from rotating around vertical rail 94 A. Upper arm 94 B includes a recessed area 94 BC into which a code strip (not shown) is attached to cooperate with transducer 96 . [0094] Vertical rail 94 A is movably attached to modified vessel centering ring 75 in order to render combined shaft centerline offset and height measurement device 70 compatible with vessels V of different sizes. Preferably, an annular bearing (not shown) similar to annular bearing 99 is attached to modified vessel centering ring 75 and vertical rail 94 A is extended therethrough. In addition, means such as a spring (not shown) is provided to bias vertical rail 94 A (and thus height measurement module 90 in its entirety) downwardly. [0095] To complete the measurement system, it will be readily apparent that combined shaft centerline and offset measurement device 70 is operable in conjunction with control/display console 60 in FIG. 3A, although some reprogramming is necessary. Combined shaft centerline and offset measurement device 70 can be made to communicate with control/display console 60 by running appropriate data lines such as conduits EC from transducers 86 , 96 to control/display console 60 . [0096] The operation of combined shaft centerline and offset measurement device 70 will now be described. Stainless steel ball 65 is inserted into vessel V in order to locate lowermost point 19 of hemispherical end region 16 . Modified vessel centering ring 75 , equipped with combined shaft centerline and offset measurement device 70 , is then fitted onto rack 18 of dissolution testing station DTS over one of vessels V. At this time, rear face 82 F of radially outwardly biased sensor body 82 of each centerline offset measurement module 80 makes contact with lateral inside surface ID of vessel V. Additionally, lower end portion 94 CB of downwardly biased vertical plunger 94 of height measurement module 90 makes contact with stainless steel ball 65 . [0097] Shaft S is then lowered into vessel V to its normal operating position. Shaft S passes through bore 75 B of modified vessel centering ring 75 while being lowered into vessel V. Also, paddle P contacts one or more upper guide members 84 B of lateral plungers 84 while shaft S is being lowered into vessel V, thus urging one or more of lateral plungers 84 outwardly to clear the way for paddle P to pass downwardly. Once shaft S reaches its normal operating position, plunger tips 84 A of radially inwardly biased lateral plungers 84 are in full contact with shaft S. [0098] Assuming shaft S is offset from the central axis of vessel V, one or more of lateral plungers 84 of centerline offset measurement modules 80 will have displaced outwardly with respect to a predetermined zero reference position for displaced lateral plunger or plungers 84 . Hence, lateral plungers 84 operate in a manner analogous to lateral plunger 44 of centerline offset measurement device 40 . Each lateral plunger 84 if displaced will have moved by a distance equal to a displacement magnitude along the radial direction of that particular lateral plunger 84 . This physical event is measured and converted into an electrical signal by the coaction of transducer 86 and its associated code strip 106 as described hereinabove. Accordingly, three signals representing the displacement magnitudes at the 120° positions along lateral inside surface ID of vessel V are sent to control/display console 60 . Offset distance OT is then preferably calculated by employing the sequence of steps including the trigonometric equations described hereinabove. [0099] Height measurement module 90 also operates when shaft S is installed in vessel V. Before the bottom end of shaft S or its paddle P reaches its lowermost position within vessel V, upper end portion 94 BB of upper arm 94 B of vertical plunger 94 is biased in its highest position above lower end portion 94 CB of lower arm 94 C. This constitutes a zero reference position for vertical plunger 94 . As shaft S is being lowered into vessel V, paddle P makes contact with upper end portion 94 BB. By the time shaft S reaches its final, normal operating position, paddle P will have urged upper end portion 94 BB downwardly towards lower end portion 94 CB against the biasing force of spring 98 . As the code strip for vertical plunger 94 is fixedly mounted in recessed area 94 BC of upper arm 94 B, the code strip moves downwardly by the same distance as upper end portion 94 BB. This distance constitutes the displacement magnitude for vertical plunger 94 , which is encoded by transducer 96 , and a signal is sent to control/display console 60 for further processing. One way to derive or interpret the height of paddle P above lowermost point 19 of vessel V is to add together values for the measured displacement magnitude, the height of upper end portion 94 BB, the height of lower end portion 94 CB, and the diameter of stainless steel ball 65 . [0100] It will be understood that while the Figures depict control/display console 60 as being portable and designed for remote operation, the present invention encompasses a variation wherein control/display console 60 is integrated into dissolution testing station DTS. For example, the operative components of control/display console 60 can be housed within programmable systems control module 20 of dissolution testing station DTS (see FIG. 2). [0101] [0101]FIGS. 13A and 13B illustrate by way of example a flow diagram of a test routine executable by software written for control/display console 60 . The particular test routine illustrated manages the operation of shaft centerline offset and height measurement system 30 with centerline offset measurement device 40 and height measurement device 50 . It will be understood, however, that the software can be rewritten without undue experimentation and adapted for use of control/display console 60 with combined shaft centerline offset and height measurement device 70 . It is also to be noted that this test routine can be configured, for example, to test up to 30 dissolution testing stations DTS and up to 8 shafts S and corresponding vessels V per dissolution testing station DTS. Therefore, a total of 240 shaft sites can be tested in a single test routine if desired. [0102] Referring again to FIGS. 13A and 13B, display screen 60 C of control/display console 60 displays a main menu at step 115 , prompting the user to select either a test run for shaft height measurement or a test run for shaft offset measurement. If the user selects a test run for shaft height measurement, a shaft height measurement subroutine 120 - 137 is initiated. On the other hand, if the user selects a test run for shaft offset (or “ctr line”) measurement, a shaft offset measurement subroutine 140 - 157 is initiated. [0103] When the shaft height measurement subroutine is initiated, the user is prompted at step 120 to assign an integer from 1 to 30 to the dissolution testing station presently being tested in order to distinguish that testing station from other testing stations to be tested. The user is then prompted at step 125 to input an identification for that particular testing station, such as a serial number. Shafts operating in that testing station are assigned numbers according to the respective positions of the shafts in the testing station, such as 1 through 6 or 1 through 8. Thus, the user is prompted at step 130 to either initiate testing of a particular shaft, proceed to the next shaft, or exit the shaft height measurement subroutine and return to the main menu. [0104] If the user desires to test that particular shaft, the user is prompted at step 131 to input an identification for the shaft, such as a serial number. Next, the user is prompted at step 132 to input an identification for the vessel in which the shaft operates. The user is then prompted to place the stainless steel ball into the vessel at step 133 , install the shaft height measurement device at step 134 , press the vertical plunger upwardly against the paddle or basket of the shaft in order to obtain a zero reference reading at step 135 , and lower the shaft equipped with the height measurement device into the vessel at step 136 . Once the shaft height measurement has been taken and appropriately interpreted, a readout or indication of the shaft height is displayed at step 137 and the user is prompted to test another shaft in the particular testing station being tested. [0105] When the shaft centerline offset measurement subroutine is initiated by selection at step 115 , the user is prompted at step 140 to assign an integer to the dissolution testing station presently being tested. The user is then prompted at step 145 to input an identification for that particular testing station. Next, the user is prompted at step 150 to either initiate testing of a particular shaft identified by its position number, proceed to the next shaft, or exit the shaft centerline offset measurement subroutine and return to the main menu. [0106] If the user desires to test that particular shaft, the user is prompted at step 151 to input an identification for the shaft. Next, the user is prompted at step 152 to input an identification for the vessel in which the shaft operates. The user is then prompted to install the shaft centerline offset measurement device at step 153 , and to lower the shaft equipped with the offset measurement device into the vessel at step 154 . After a key input is entered at this position, the user is prompted at step 155 to rotate the shaft 120°. A key input is requested to indicate the completion of this step. The user is then prompted at step 156 to rotate the shaft another 120°, and a key input is requested to indicate the completion of this step. Once the measurements taken at these positions have been appropriately interpreted and the offset distance calculated, a readout or indication of the shaft centerline offset is displayed at step 157 and the user is prompted to test another shaft in the particular testing station being tested. [0107] These steps are repeated for every shaft and dissolution testing station desired by the user to be tested. [0108] It will be understood that in the case where the centerline offset is measured by making one full rotation around the vessel in order to sample a plurality of displacements, the steps of the test routine are modified accordingly. It will also be understood that in the case where a testing routine such as that just described is adapted for use in conjunction with combined shaft centerline offset and height measurement device 70 , the total number of steps required by the test routine can be reduced. [0109] It will be further understood that various details of the invention may be changed without departing from the scope of the invention. Furthermore, the foregoing description is for the purpose of illustration only, and not for the purpose of limitation—the invention being defined by the claims.

Apparatus and methods for measuring the amount by which the centerline of a shaft disposed in a vessel is offset from the central vertical axis of the vessel, and for measuring the height of such shaft above the inside bottom of the vessel. Apparatus includes a shaft centerline offset measurement device, a shaft height measurement device, and a control/display console. Each measurement device includes a transducer or optical encoder for sensing a displaced position of a biased plunger to which a code strip is mounted. The devices may be combined into a single shaft offset and height measurement device. Improved methods include calculating shaft offset based on a plurality of readings from the transducer, and applying trigonometric relationships. The apparatus and methods are particularly useful in the verification of paddle or basket shafts utilized in dissolution testing stations, so that the dissolution testing protocol complies with government agency guidelines.

CROSS-REFERENCE TO RELATED APPLICATIONS None. TECHNICAL FIELD The present invention relates to a collapsible storage cabinet. More specifically, embodiments of the present invention relate to a collapsible storage cabinet having ease of assembly, improved stability when assembled, and an improved configuration for packaging when in a collapsed state. BACKGROUND OF THE INVENTION Storage cabinets are well known and utilized in a variety of locations in homes and businesses to satisfy several needs. Storage cabinets come in many shapes and sizes to meet these wide-ranging needs. The storage cabinets may be provided to a consumer in a fully assembled state or a disassembled state, requiring the consumer to then assemble the cabinet. From a consumer perspective, it is advantageous for the storage cabinet to be fully assembled when purchased, as it is ready to use. In fact, a number of storage cabinets are manufactured and shipped in a fully assembled state. However, shipping storage cabinets in a fully assembled state requires sizeable amounts of packaging and space when in transit, resulting in increased shipping costs. These higher costs are typically passed on to the consumer through the price of the storage cabinet. Storing fully assembled storage cabinets also requires large amounts of storage space. Occupying large amounts of both storage and display space at a retailer can result in fewer cabinets being ordered by retailers due to limited inventory/display space, and therefore fewer cabinets available for consumers to purchase. From a manufacturer, transport, and retail perspective, it is more advantageous to provide the storage cabinet to the consumer in a disassembled state, such that the pieces of the cabinet can be packaged in a more efficient manner, such as in a flat and stackable box. However, requiring a consumer to assemble a cabinet having many pieces may prevent some consumers from purchasing the cabinet. Furthermore, storage cabinets of the prior art which are designed to be assembled by the consumer are often times constructed in a way to promote easier assembly. However, such storage cabinets may not provide as much structural integrity as storage cabinets designed to be assembled at a factory and shipped as a finished unit. SUMMARY In accordance with the present invention, there is provided a novel and improved storage cabinet which seeks to overcome the shortcomings of the prior art. In an embodiment of the present invention, a collapsible storage cabinet is provided having a front wall, an opposing back wall, a pair of folding sidewalls, a top wall, and a bottom wall, where the top and bottom walls are secured to the front, back and sidewalls in a way so as to be recessed within a top opening and bottom opening. In an alternate embodiment of the present invention, a wall member for a collapsible storage cabinet is provided. The wall member comprises a generally planar body, a pair of first support walls oriented generally perpendicular to the generally planar body with each of the first support walls also having a first lip oriented parallel to the generally planar body. The wall member also has a pair of second support walls oriented generally perpendicular to both the generally planar body and the first support walls with each of the second support walls also having a second lip oriented parallel to the generally planar body. In another embodiment of the present invention, a collapsed storage cabinet is provided comprising a front wall having a first pair of generally planar end faces, a back wall opposite the front wall and parallel thereto and having a second pair of generally planar end faces. The collapsed storage cabinet also comprises a pair of collapsible sidewalls with each sidewall having a plurality of hinged panels where the panels are in contact with each other and positioned such that the first pair of generally planar end faces are adjacent to and parallel to the second pair of generally planar end faces. Additional advantages and features of the present invention will be set forth in part in a description which follows, and in part will become apparent to those skilled in the art upon examination of the following, or may be learned from practice of the invention. The instant invention will now be described with particular reference to the accompanying drawings. BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS The present invention is described in detail below with reference to the attached drawing figures, wherein: FIG. 1 is a perspective view of an embodiment of a collapsible storage cabinet in a fully assembled condition; FIG. 2 is a cross-sectional side elevation view of the storage cabinet of FIG. 1 in a collapsed condition and packaged for shipment by the manufacturer; FIG. 3 is a perspective view of the storage cabinet of FIG. 1 in a collapsed condition once removed from the packaging of FIG. 2 and with portions removed from an interior cavity defined by the collapsed cabinet; FIG. 4 is an alternate perspective view of the collapsible subassembly of the storage cabinet of FIG. 3 ; FIG. 5 is a perspective view of the storage cabinet of FIG. 3 in a partially expanded condition; FIG. 6 is a perspective view of a top wall or bottom wall for the storage cabinet of FIG. 1 ; FIG. 7 is an exploded view of the storage cabinet of FIG. 1 depicting the collapsible subassembly, the top wall, the bottom wall, and the door panels; FIG. 8 is a cross-sectional view of a portion of the storage cabinet of FIG. 1 taken along the line 8 - 8 ; FIG. 9 is a perspective view of the storage cabinet of FIG. 1 in which the door panels are open; FIG. 10 is an enlarged, fragmentary, perspective view of a clip arrangement used to support a shelf in the collapsible storage cabinet taken in the area 10 of FIG. 7 ; FIG. 11 is an enlarged, fragmentary, perspective view of a tongue arrangement used to support a shelf in the collapsible storage cabinet; FIG. 12 is cross-sectional view of the tongue arrangement taken along the line 12 - 12 of FIG. 11 ; and FIG. 13 is the cross-sectional view of FIG. 12 , but with a shelf supported on the tongue arrangement. DETAILED DESCRIPTION The subject matter of the present invention is described with specificity herein to meet statutory requirements. However, the description itself is not intended to limit the scope of this patent. Rather, the inventors have contemplated that the claimed subject matter might also be embodied in other ways, to include different components, combinations of components, steps, or combinations of steps similar to the ones described in this document, in conjunction with other present or future technologies. Referring initially to FIG. 1 , a collapsible storage cabinet 100 is depicted in its fully assembled condition. The collapsible storage cabinet 100 of the present invention can serve a variety of uses. One such use is being in a garage to store tools, supplies or other similar equipment. The collapsible storage cabinet 100 includes a collapsible subassembly 101 having a front wall 102 and an opposing back wall 104 spaced a distance apart when the cabinet is in the fully assembled condition. Referring to FIG. 3 , the collapsible storage cabinet 100 is provided with a bracket 105 for hanging the cabinet 100 from a wall, if desired. The bracket 105 would be mounted to the wall and the storage cabinet would be supported thereon by way of a lip 111 along an edge of the bracket 105 interlocking with a corresponding lip 113 extending from the back side of the rear wall 104 . The collapsible storage cabinet 100 also comprises a pair of folding sidewalls 106 extending between and coupling the front wall 102 and back wall 104 , as shown in FIGS. 1 and 5 . The folding sidewalls 106 are connected to the front wall 102 and back wall 104 by a hinge 108 ( FIGS. 5 and 7 ) or other comparable device. The hinge 108 permits the one or more panels 110 , which form the sidewalls 106 , to collapse as shown in FIGS. 2-5 . Referring now to FIGS. 2, 4, and 5 , the front wall 102 and back wall 104 each comprise additional structural features which aid in the packaging of the storage cabinet 100 in its collapsed condition for shipment and storage. More specifically, the front wall 102 further comprises a pair of extensions 102 A and corresponding first pair of generally planar end faces 112 which extend from the front wall 102 . The back wall 104 , similarly, also has a pair of extensions 104 A and a corresponding second pair of generally planar end faces 114 . The first and second generally planar end faces 112 and 114 are located such that when the storage cabinet 100 is in the fully collapsed state, as shown in FIG. 4 , the first pair of generally planar end faces 112 are positioned adjacent to and parallel with the second pair of generally planar end faces 114 , thereby forming an interior cavity or open region 116 between the front wall 102 , the back wall 104 , and the collapsed sidewalls 106 . As it can be seen in FIG. 4 , when the storage cabinet 100 is in the collapsed condition, the plurality of panels 110 forming the pair of collapsible sidewalls 106 are folded so as to be in contact with each other. Furthermore, the plurality of panels 110 are folded so as to also be contained between the front wall 102 and back wall 104 . That is, as can be seen in FIGS. 5 and 7 , the plurality of panels 110 which form the collapsible sidewalls 106 are hinged to the extensions 102 A of the front wall 102 and extensions 104 A of the back wall 104 so that the hinges 108 are not visible from the exterior of the collapsible storage cabinet 100 when it is in its fully assembled position. A lip 103 extends beyond an inner edge of one of the panels 110 on each side to prevent the panels 110 from opening or flexing outward. Further, in the illustrated embodiment, the hinges 108 are not standard, piano-type hinges in that they do not directly couple interior corners of the extensions 102 A, 104 A to interior corners of the panels 110 , as one would normally think a hinge would do. Instead of keeping the corners adjacent to each other throughout the collapsing of the cabinet 100 , the hinges 108 are constructed to move the panels 110 between being aligned with the extensions 102 A, 104 A in the fully assembled position, as best illustrated in FIG. 7 , to being adjacent the extensions 102 A, 104 A in the fully collapsed position, as best illustrated in FIG. 2 . As illustrated in FIG. 2 , the hinges 108 permit each panel to be moved to a location generally perpendicular to and next to or inside of, as opposed to cattycorner or diagonal, the extension to which it is connected. This moves the panels 110 out of the way so the front extensions 102 A almost touch (or do touch) the rear extensions 104 A. If the panels 110 were connected to the extensions 102 A, 104 A with piano hinges, the abutting panels 110 would space the extensions 102 A, 104 A further apart, thus making the depth (i.e., the vertical dimension in FIG. 2 ) of the collapsed cabinet unit greater. As illustrated in FIGS. 2, 5 and 8 , the hinges 108 accomplish this by being attached to an inner face of the extensions 102 A, 104 A and an inner face of the panels 110 . The hinges include an angled bracket portion that spans the space between the panels 110 and the extensions 102 A, 104 A in the fully assembled position. The hinges 108 , as best seen in FIGS. 7 and 10 , also include a plurality of openings 115 therein into which a clip 117 may be placed. A clip 117 may be placed in an opening in each of the hinges 108 at a same vertical height and the shelf 150 may be removably supported thereon. The storage cabinet 100 further comprises a front frame 118 , as shown in FIGS. 1, 4, and 5 , with the front frame 118 encompassing one or more doors 120 . As it can be seen from FIGS. 1, 4, 5, 7, and 9 , the embodiment of the collapsible storage cabinet 100 depicted has two doors 120 which open outward, thereby providing access to the inside of the storage cabinet 100 . The doors 120 are hinged to a side portion of the front frame 118 in a traditional cabinet-style arrangement. However, the exact number and arrangement of the one or more doors 120 can vary. The one or more doors 120 and front frame 118 also include a locking mechanism 122 permitting the user of the storage cabinet 100 to selectively lock the one or more doors 120 . A key type locking mechanism 122 is utilized in the collapsible storage cabinet 100 shown in FIGS. 1, 3-5, and 7 . However, it is possible to utilize other types of locking mechanisms, such as a combination lock. Referring now to FIG. 6 , the collapsible storage cabinet 100 also comprises a wall member 130 having a unique structural design. The wall member 130 is preferably used as a top wall 132 and/or a bottom wall 134 for the collapsible storage cabinet 100 , as shown in FIGS. 1, 7, and 9 . The wall member 130 has a generally planar body 136 having a length dimension L and a width dimension W. The wall member 130 also has a pair of first support walls 138 , oriented generally perpendicular to the generally planar body 136 , and a pair of first lips 140 that are parallel to the generally planar body 136 . The wall member 130 also comprises a pair of second support walls 142 , oriented generally perpendicular to the generally planar body 136 , as well as the pair of first support walls 138 . Each of the second support walls 142 also comprise a second lip 144 which, like the first lip 140 , is generally parallel to the generally planar body 136 . The first and second lips 140 and 144 each contain one or more openings 146 to aid in securing the top wall 132 and the bottom wall 134 to the collapsible subassembly 101 . The one or more openings 146 correspond to respective openings 148 in top and bottom portions of the front wall 102 , the back wall 104 , and the sidewalls 106 , as shown in FIGS. 5 and 7 . The wall member 130 , shown in FIG. 6 , can be fabricated from a single piece of sheet metal that is cut and formed to the desired shape by a bending process such as a press brake. Utilizing such a process provides an economical and reliable means of fabrication. More specifically, the wall member 130 has a generally planar body 136 , which is cut and then folded on each of its four sides to form the first support walls 138 and second support walls 142 . Then the first and second lips 140 and 144 are formed by bending a portion of the first and second support walls, 138 and 142 , respectively. The one or more openings 146 can be placed in the wall member 130 at a convenient time in the manufacturing process. Referring back to FIG. 2 , the storage cabinet 100 shown in its collapsed and packaged condition. The collapsed condition provides a more compact product to be shipped to retailers. More specifically, the storage cabinet, when collapsed, defines an open region 116 , as discussed above. The open region 116 is sized such that the top wall 132 , bottom wall 134 , one or more shelves 150 , and the bracket 105 , along with any fasteners, clips, or other hardware, can be placed within the open region 116 for purposes of packaging and shipping the collapsible storage cabinet 100 . FIG. 2 also shows how the collapsible storage cabinet 100 fits within a limited amount of disposable packaging 107 (e.g., cardboard), which may or may not include multiple layers and/or padding 109 (e.g., foam) so as to protect the collapsible storage cabinet 100 when in transit. The storage cabinet 100 of the present invention provides numerous benefits over cabinets of the prior art, some of which are quick and easy assembly, improved structural support, and enhanced storage features. As shown in FIG. 2 , the collapsible storage cabinet 100 provides a more efficient packaging, thereby using less storage space for shipping and in retail locations. With respect to assembly of the collapsible storage cabinet 100 , once the top wall 132 , bottom wall 134 , and one or more shelves 150 are removed from the packaged unit in FIG. 2 , the collapsible storage cabinet 100 is opened by separating the front wall 102 from the back wall 104 , as shown in FIG. 5 . Then, once the folding sidewalls 106 are fully extended, the top wall 132 is secured to the upper portion of the front wall 102 , the back wall 104 and the sidewalls 106 , as shown in FIG. 7 . A plurality of removable fasteners 152 , such as screws or bolts, are placed through the one or more openings 146 in the first and second lips 140 and 144 and into the corresponding openings 148 in the front wall 102 , back wall 104 and sidewalls 106 . The corresponding openings 148 may be threaded such that the removable fasteners 152 engage and secure the top wall 132 to the storage cabinet 100 . It is possible for other types of fasteners 152 to be used such as ¼ turn fasteners or push pin connectors. The bottom wall 134 is secured to the collapsible storage cabinet 100 in the same manner as the top wall 132 . Finally, the one or more shelves 150 are placed in the storage cabinet 100 , as shown in FIG. 9 . In the event the storage cabinet 100 is to be collapsed, the one or more shelves 150 are removed, the fasteners 152 are removed, and the top wall 132 and bottom wall 134 are then removed. The storage cabinet 100 can then be collapsed to the flattened condition shown in FIGS. 3 and 4 . The design of the top wall 132 and bottom wall 134 also provide increased structural stability for the storage cabinet 100 . Referring to FIG. 8 , a partial cross-sectional view of the storage cabinet 100 depicting the top wall 132 is shown. A similar construction occurs with respect to the bottom wall 134 . This cross section view of the storage cabinet 100 shows the generally planar body 136 , first support walls 138 and first lips 140 . The first support walls 138 , which are generally perpendicular to the generally planar body 136 , are thereby generally parallel to the inner portions of the front wall 102 and back wall 104 , providing increased structural rigidity to the collapsible storage cabinet 100 , helping to prevent any twisting or lateral movement of the front wall 102 or back wall 104 , and helping to prevent collapsing of the folding sidewalls 106 . The recessed, tray-like shape of the wall member 130 , provides for a portion of the wall member 130 being between the front wall 102 , the back wall 104 , and the sidewalls 106 when the collapsible storage cabinet 100 is in its fully assembled condition, thereby providing enhanced anti-collapsibility functionality when compared to a flat top or bottom that merely spans across the upper or lower edges of the walls 102 , 104 , 106 . In addition to the structural benefits discussed above, the geometry of the top wall 132 also provides an enhanced feature for the collapsible storage cabinet 100 . That is, the tray-like shape of the top wall 132 allows for additional items, such as small tools or supplies, to be stored on top of the storage cabinet 100 without a risk of them falling or rolling off of the top wall 132 . The collapsible storage cabinet 100 is preferably fabricated from sheet metal such as stainless, galvanized or tool steel. However, for lighter and less rugged applications, it is possible for the collapsible storage cabinet 100 to be fabricated from lighter weight materials, such as plastic. Turning now to FIGS. 11-13 , an alternate method of supporting a shelf in the collapsible storage cabinet 100 is disclosed. To provide increased rigidity to the collapsible storage cabinet 100 when in the fully assembled position, the shelf 150 may be coupled to the hinges 108 , one or more panels 110 , the sidewalls 106 , and/or the back wall 104 . With the use of the clips 117 discussed above, the shelf 150 simply sits on the clips 117 . However, by replacing the openings 115 and clips 117 with a tongue 154 , a more secure connection may be made. As illustrated in FIG. 11 , a tongue 154 may be formed where the opening 115 would otherwise be located. The tongue 154 may be formed by bending a portion of the metal into tongue-like configuration. The tongue 154 defines a space or gap 156 between the tongue 154 and the panel or wall in which it is formed (e.g., hinge 108 , sidewall 106 , back wall 104 , etc.). A bottom portion 158 of the shelf 150 is provided with one or more openings 160 . The shelf is placed inside the collapsible storage cabinet 100 when it is in the fully assembled position in a horizontal orientation above the tongues 154 . It is then lowered down toward the tongues, wherein a distal end 162 of the tongues 154 are received in the openings 160 in the bottom of the shelf 150 . The shelf 150 is lowered until a bottom of the shelf 150 abuts the tongue 154 , as illustrated in FIG. 13 . A portion of the shelf 150 is pinched between the tongue 154 and the hinge 108 to, in essence, clamp the shelf 150 in place. This makes the shelf 150 more secure, but also ties the panels 110 together and to the shelf, for a more secure arrangement. The present invention has been described in relation to particular embodiments, which are intended in all respects to be illustrative rather than restrictive. Alternative embodiments will become apparent to those of ordinary skill in the art to which the present invention pertains without departing from its scope. From the foregoing, it will be seen that this invention is one well adapted to attain all the ends and objects set forth above, together with other advantages which are obvious and inherent to the system and method. It will be understood that certain features and sub-combinations are of utility and may be employed without reference to other features and sub-combinations. This is contemplated by and within the scope of the claims.

A collapsible storage cabinet having an improved structure and assembly technique is disclosed. The storage cabinet is designed to collapse to a compact size to minimize required shipping and retail space usage, while providing for ease of assembly by a consumer and improved structural design via recessed top and bottom walls. The collapsible storage cabinet includes a collapsible subassembly having a front wall, an opposing back wall, and a pair of folding sidewalls extending between and coupling the front wall and back wall. Top and bottom walls are selectively secured to the subassembly to maintain the cabinet in a fully assembled state.

BACKGROUND OF THE INVENTION [0001] 1. Field of the Invention [0002] The invention relates to appliance security systems, in particular security devices for prevention or deterrence of theft of appliances which are permanently installed in buildings. It will be convenient to describe the invention with particular reference to application for prevention of theft of appliances which are installed during construction of a building, especially in a domestic dwelling or dwellings, although it would be appreciated that the invention may have wider application. [0003] 2. Description of the Related Art [0004] During construction of domestic dwellings a range of appliances are generally installed. These appliances may include gas, solar or electric hot water services, heating systems, furnaces, air-conditioning units, ovens, stoves, dishwashers, in-built vacuum systems, garage door activators and motors, spa baths and associated equipment and pumps and filters for swimming pools. Many of these appliances must be installed outside the building. [0005] The cost of such appliances can be quite substantial and as a consequence, such appliances are often targeted for theft. Although such items are not readily portable, security on building sites is often inadequate and these appliances are particularly vulnerable. Security fencing and security patrols may be provided to improve security on building sites, however, the effectiveness of such measures is limited. The costs of 24 hour security patrols may be prohibitive. In addition, some theft of appliances may be by people authorised to access the site, making enforcement difficult. A range of anti-theft devices have been proposed for more portable electronic apparatus such as televisions, video cassettes recorders, personal computers, stereo equipment and the like for example, in U.S. Pat. No. 4,987,406. These devices generally render the apparatus inoperative after occurrence of a disabling event like movement of the apparatus from one place to another. This type of apparatus are more frequently the target of theft from domestic residences after they have been purchased by the consumer and taken home, installed and used as they are generally easily removed during opportunistic breakings and enterings. [0006] The likelihood of theft of permanently installed appliances such as fixed air-conditioning after installation while the building is occupied is quite remote but much higher prior to installation on the building site. [0007] Clearly, the costs associated with replacing stolen appliances is undesirable and leads to greater building costs and/or insurance premiums. Thus, it is an object of the invention to reduce instances of theft of appliances particularly from building sites. It is also an object of the invention to provide such security functionality without major or costly alteration to existing appliance hardware or software. SUMMARY OF THE INVENTION [0008] In accordance with one aspect of the invention there is provided an appliance security system comprising: a controller for selectively enabling and disabling operation of the appliance, a lock for the controller, the lock having a first condition wherein it prevents the controller from functioning, and a code entry facility for co-operation with the lock, wherein transmission of a predetermined code from the code entry facility to the lock changes the lock to a second condition at which the lock is deactivated thereby allowing functioning of the controller whereby the appliance is secured against unauthorized use whilst the lock is in its first condition. [0012] Preferably, the appliance is one which is to be permanently installed and performs a domestic utility function especially a heating appliance, air-conditioner or cooler, although other appliances such as permanently installed cooking, washing, vacuuming, door actuation, filtering or pumping appliance or the like may be the subject of other embodiments. [0013] The appliance will have a controller for controlling the operation of the appliance, which may be a simple on/off operation, or a more complex on/off operation coupled with a thermostatic control or secondary control functions. It will be appreciated that in many appliances the control means incorporates a microprocessor or other electronic circuitry. In the normal use of the appliance the controller is switched by the user to operate the appliance for example, setting a desired temperature on a heating or cooling appliance. The controller may be located on the appliance itself or it may be located remote from but in communication with the main appliance apparatus. For example, the controller may be a thermostat control located in a selected situation in a dwelling, where the main heating or cooling appliance apparatus is located in a discrete position outside the dwelling. [0014] There is also provided a lock to prevent the selective enablement and disablement of the controller. In a preferred embodiment the appliance is supplied from the manufacturer with the lock in a locked state so that the controller cannot function. In other words, once the appliance leaves its place of manufacture it cannot be operated until the lock is deactivated therefore rendering the appliance useless unless it is subsequently unlocked thereafter. In one embodiment, the lock may act on a uniquely coded remote control unit which communicates with the controller, thus preventing a signal from being transmitted from the remote control unit to the controller when the lock is activated. [0015] The lock is preferably an electronic lock, i.e., circuitry or software which locks the functioning of the controller. [0016] There is further provided a code entry facility for conveying a code to permanently deactivate the lock when the code matches a corresponding memorised code in the lock. Generally the code would be conveyed to the lock by the code entry facility after installation of the appliance and after the building has reached a stage where the risk of theft has passed. In one embodiment, the code entry facility for conveying the code is a separate electronic key which may be plugged into a communications port in the appliance to transmit the code to unlock the lock. After this operation, the electronic key, which is preferably of low cost and low complexity, may be disposed of as it has no further function. [0017] In yet another embodiment, the appliance can be locked out of operation until an authorized installer deactivates the lock for an initial period, and once that period has expired, the lock then reactivates to prevent functioning of the controller. The lock may then be subsequently deactivated, for example by the home owner, once the building becomes occupied, as described above. Preferably the lock is permanently deactivated at this stage as the risk of theft of the appliance has passed. The initial period for which the lock is deactivated may be selected from one of a number of options, for example 12 hours, 48 hours or 30 days. This enables the appliance to be installed, operated and commissioned then locked out prior to hand over to the end customer. Such a code entry facility may be used by an authorized installer for multiple appliances. [0018] In another embodiment, the code entry facility for conveying the code is a remote control unit supplied with the appliance which is normally used to communicate with the controller. The remote control may have a dedicated ‘activation’ program operated prior to the first use of the appliance where the code is transmitted and the lock may be permanently deactivated. [0019] In another embodiment there is provided a method of deferring theft of an appliance for fixing in a building, the appliance including a controller for selectively enabling and disabling operation of the appliance, the method comprising the steps of: (i) providing a lock for the controller; (ii) conditioning the lock to a first condition whereat it prevents functioning of the controller; (iii) providing a data entry facility for use with the lock, and (iv) conditioning the data entry facility and the lock such that entry of a first code into the data entry facility will deactivate the lock to a second position whereby it will allow functioning of the controller, wherein theft of the appliance is deterred whilst the lock is in the first condition whereby the appliance cannot be activated. [0024] It will now be convenient to describe certain aspects of the invention with reference to preferred embodiments and drawings. It is to be understand that the following description relates to preferred embodiments only and is not intended to limit the scope of the invention. BRIEF DESCRIPTION OF THE DRAWINGS [0025] FIG. 1 is a schematic diagram of an appliance and code entry facility of the present invention. [0026] FIG. 2 is a schematic diagram of an appliance and remote controller with code entry facility of the present invention. [0027] FIG. 3 is a plan of an electronic key for use with the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT [0028] In FIG. 1 , appliance 1 has a controller 3 for selectively enabling an disabling operation of the appliance 1 . Where the appliance 1 is, for example, an air conditioner, heater, filter or pump, the controllers may control functioning of a motor, valve, burner or combination of these, generally shown as part 5 . Lock 7 is associated with controller 3 and in a first condition prevents the controllers from functioning and controlling part 5 . In the embodiment of the appliance 1 shown in FIG. 1 , there is no pre-existing method of entering digital data into lock 7 because such an appliance does not use a communications socket, but may use a “Honeywell”™ type input. Because there is a need to transmit a digital code to controller 3 to unlock it, and a simple contact is not generally suited to do this, a multi-pin socket 9 is provided as a communications port. Electronic key 11 includes a key body 13 and a multi-pin plug 15 which can be located in the corresponding multi-pin socket 9 . Key body 13 has data entry keys more clearly shown in FIG. 3 . Keys 17 a , 17 b and 17 c are each labelled with a different time duration, such as 12 hours, 48 hours or 30 days. [0029] In one embodiment, at an appropriate point during the manufacture of appliance 1 , a code is entered into a non-volatile memory of controller 3 . Different appliances may be designated with different individual codes. Once the code is installed the appliance 1 may be pre-programmed to only run for a limited time, for example, an hour, to enable testing of the appliance immediately after installation by a tradesman. After that initial testing period has expired, the main controller 3 will be locked out from functioning until a further code matching the individual code is entered into lock 7 to disable the lock out function. Preferably, appliance 1 is supplied from the manufacturer with lock 7 in a locked state so that controller 3 is prevented from functioning. Once the tradesman has then installed the appliance and is ready to test it, multi-pin plug 15 is inserted into multi-pin socket 9 and one of keys 17 a, b or c is pressed so that the lock changes to a second condition where it is deactivated for a limited time. Electronic key 11 is then removed from multi-pin socket 9 and the tradesman can test appliance 1 . After the selected time period has expired lock 7 will automatically revert to its first condition where it again prevents the controllers from functioning. [0030] Appliance 1 then remains locked until the danger of theft during construction of the house or building has passed. When appliance 1 is ready to be commissioned to commence its normal functioning, electronic key 11 , or some similarly configured electronic key with a multi-pin plug can be inserted into multi-pin socket 9 and a button 19 depressed so that electronic key 11 sends a code to lock 7 to change the lock 7 to the second condition where the lock is deactivated and allowing functioning of the controllers. Preferably this permanently deactivates lock 7 . [0031] In an alternative embodiment shown in FIG. 2 , appliance 1 is controlled by way of a remote control 21 having a wireless transmitter 23 communicating with a wireless receiver 25 associated with slave controller 27 . Slave controller 27 controls the functioning of part 5 which again may be a motor, pump, valve, or the like. In this embodiment the master controller is remote from appliance 1 and is capable of transmitting a digital signal to wireless receiver 25 . It is therefore convenient that instead of using a separate electronic key as shown in FIG. 1 , the remote control 21 can be programmed to transmit the locking and unlocking data to lock 7 via wireless receiver 25 which will comprise circuitry associated with slave controller 27 . [0032] The use of the lock code and unlocking function can be limited to a once only action to avoid accidental locking of the product through the rest of its serviceable life. This would stop any later problems of the appliance 1 being locked inadvertently long after it has been installed and the building in which it is installed has been occupied. [0033] To avoid altering any software already used in a remote 21 control which may conventionally be supplied with an appliance 1 the address facility to establish communication between the remote control processor and the main control may be used as is. On a ‘virgin unit’, the communication address function is carried out as normal. In one embodiment, another 4 digit code may be entered straight after the address code and is accepted as a PIN number or to activate the lock function, initialising a pre-programmed PIN number. The unlock function is performed in the same manner, unlocking the unit and disabling it from ever being locked again. This method means the existing remote controllers used in such appliances can incorporate the invention without alteration. Changes can be made to the main controller software to enable use of its non-volatile memory in this manner. [0034] Alternatively, the appliance 1 may be manufactured and supplied in an unlocked state, and activation of the lock-out function may initially be caused by entry of a code into the main control. [0035] In one embodiment, each key may be code set by use and cannot be altered. The PIN number is also attached to the key so that a control board can be locked with a matching number. There also is the possibility of the manufacturer maintaining a master key to which access is restricted and coding of the master key may change from time to time. [0036] In one embodiment, after the key is used once for final unlocking there is no further use for it and it may be thrown away. It may also be possible to lock the unit, provided it is a “virgin” unit as outlined previously. [0037] This key may be a small PCB, with only one dedicated integrated circuit. The manufacture during production may program them in sequential numbers which are unalterable. The operation power for the key may be obtained from the multi-pin socket 9 of the appliance 1 so the content of the key is kept quite simple. [0038] In some circumstances it may be necessary to recall an individual PIN number; for example if the PIN is lost. In one embodiment a fault LED of the controller 3 could identify the PIN code and could be accessed in a suitable form. For added security the observed code may be in the form of a number of flashes arranged in digits of the fault LED. This could be either the actual representation of the PIN code which has to be input or an encrypted code which must be passed through a ‘filter’ available only at the manufacturer's selected centres, where the actual unlock code is determined. Obviously this process is only used when the assigned PIN number is lost and verification of those wishing to know is ascertained. The filter may be a special algorithm performed on flash count reading that produces the actual 4 digit unlock code. This is obviously a higher level of security designed to stop the unlock code recovery being easily obtainable by those in the “know” and to delete the necessity of a database of unlock codes to serial numbers being stored. [0039] The above is one concept and, there are many possible variations of the above scheme using a PIN number system. [0040] It is to be understood that various alterations, modifications and/or additions may be introduced into the parts previously described without departing from the spirit of the invention.

An appliance security system to secure appliances such as air or water heaters, air conditioners, pumps, cooling, cooking or washing appliances against theft from building sites. The system includes a lock means acting on control means of the appliance, and code entry means wherein entry of the code into the code entry means permanently deactivates the lock. This is performed by an authorised person after the risk of theft has diminished.

This is a Continuation-in-part application of U.S. patent application Ser. No. 352,496 filed Feb. 25, 1982, now U.S. Pat. No. 4,516,881. DISCLOSURE STATEMENT Reference is made to the following publications which provide information regarding the art of vertically moored platforms. A. The Vertically Moored Platform, for Deepwater Drilling and Production; by M. Y. Berman, K. A. Blenkarn, and D. A. Dixon; OTC Paper #3049, Copyright 1978 Offshore Technology Conference; and B. Motion, Fatigue and the Reliability of Characteristics of a Vertically Moored Platform; by P. A. Beynet, M. Y. Berman, and J. T. von Aschwege; OTC Paper #3304; Copyright 1978, Offshore Technology Conference. Reference is also made to U.S. Pat. No. 4,127,005 issued Nov. 28, 1978, entitled: "Riser/Jacket Vertical Bearing Assembly for Vertically Moored Platform" and U.S. Pat. No. 4,130,995 issued Dec. 26, 1978, entitled: "VMP Riser Horizontal Bearing". U.S. Pat. Nos. 4,127,005 and 4,130,995 are assigned to the assignee of this application. BACKGROUND OF THE INVENTION 1. Field of the Invention This invention lies in the field of vertically moored platforms (VMP) or other floating structures, for offshore, deepwater oil production which are connected to anchors in the sea floor by large diameter pipes commonly called riser pipes. More particularly, it concerns improvements in the manner by which the riser pipes are attached at their upper ends to the floating platform, and at their lower ends to anchor means at the mudline, such as conductor pipe set in holes driven into the sea floor. The riser pipes are maintained in tension at all times. When the platform is directly over the conductor pipes, there is no deflection in the riser pipes, and therefore no lateral stress in the riser pipes. However, as the pressure of wind, tide and current causes the platform to move laterally, there must be a bending of the riser pipes. 2. Description of the Prior Art The vertically moored platform (VMP) is anchored by vertical pipes called riser pipes, kept under high tension. As the platform and jacket move horizontally, under the influence of wind, wave and current, the riser pipes are deformed. The high tension has a tendency to concentrate the bending deformation in the riser pipes at each end of the risers, where they extend vertically into the ground at the bottom end, and into the platform at the upper end. These large deformations are detrimental to the risers. To distribute these deformations along the riser pipes, to decrease the maximum stresses, terminators have been designed. The terminators are sections of pipe constructed of varying diameter and wall thickness, the diameter and wall thickness both decrease from a mid-section towards each end, so that the flexibility of the end portions is greater than at the mid portion of the terminator. This variable flexibility introduced into the riser pipe system by the terminator distributes the curvature and helps appreciably to reduce the maximum stresses in the riser pipes. Horizontal bearings have been introduced and positioned at the mid-section of the terminator, so that the terminator itself can rotate in a vertical plane throughout its axis, and, therefore, distribute part of the bending above and below the horizontal bearing, which supports the riser. SUMMARY OF THE INVENTION In the past, terminators were made as short as possible from the point of rigid connection to the midpoint, which is held by a horizontal bearing. However, it has been found that if such portion is lengthened and allowed to bend with certain limits, then the overall lengths and thickness of the terminator can, surprisingly, be reduced. We have found that by use of our invention a greater flexibility in angular deflection at the support point (which may for convenience be called rotation) can be provided without increased stress in the terminator/riser structure, while permitting the design of a smaller terminator with a consequent saving of construction and installation cost. It is a primary object of this invention to provide a terminator and terminator extension, for anchoring the VMP or other floating structure to the upper end of each riser pipe, and also to provide a terminator and terminator extension at the lower end of the riser when it connects to anchor means at the sea floor. It is a further object to provide a novel bearing arrangement for transmitting axial and lateral forces from the riser pipe to the jacket leg. These and other objects are realized and the limitations of the prior art are overcome in this invention by using (a) a terminator and (b) a terminator extension, which when (a) and (b) are combined may be called a "multiterminator" (1) to anchor the upper end of the riser pipe to legs or other appropriate structures of the vertically moored platform and (2) to anchor the lower end of the riser pipe in the conductor pipe at the mudline. A terminator is a steel tubular device, made of pipe sections of varying length, diameter and wall thickness so that the outer contour of the terminator varies from a cylindrical mid-section, where it is of maximum diameter and selected length, tapering towards both ends. Normally, one end is farther from the largest diameter portion than the other end and consequently tapers more slowly and gradually than does the shorter end. The precise diameters and wall thicknesses vary throughout the length of the tapered portions and are designed to provide a graduated bending as a function of position on either side of the widest portion of the terminator, where it is mounted in an encircling sleeve supported in a leg or jacket of the VMP at the top and supported at the bottom by a pile secured in the earth. In the first or long terminator of a multiterminator mounted to a floating structure, the longest tapered end is directed downwardly and becomes an extension of the riser pipe which continues downwardly to the mudline where it is connected to a corresponding first or long terminator and a terminator extension, both making up a second multiterminator. In order to provide tension in the riser pipe, which is necessary to provide the properly controlled motion of the VMP, an axial or thrust bearing can be provided between the terminator and the encircling sleeve, so that the tension in the riser pipe can be transmitted to the jacket of the VMP. In accordance with our invention the upper short end of the first or long terminator is preferably connected to a short length of riser pipe and then to a second or "short" terminator structure which is connected to surface equipment on the deck of the VMP. A second or upper horizontal bearing can be, but not necessarily, attached between the sleeve inside a leg of a VMP and the second or short terminator so that the pipe passing through the two horizontal bearings can be deflected at each point. Thus the total deflection by this type of rotation support will permit a reduction in stress along the pipe, from the long terminator up to the surface, without providing a very large deflection in the vicinity of the first or lower horizontal bearing. By the use of a terminator extension, the combined length, weight and cost of the terminator and extension is much less than in the case where the terminator is used alone. As mentioned, the terminator and extension can be supported in a sleeve inside the jacket (or leg) of the VMP or a floating structure. We have found that an increased flexibility can be provided if the lateral restraints of the horizontal bearings are flexible, in the sense that the pipe can bend in a vertical plane about the center of the horizontal bearing which then acts as a buffer against which the pipe is being bent and the two ends are pressed in a direction opposite the thrust of the bearing. BRIEF DESCRIPTION OF THE DRAWINGS These and other objects and advantages of this invention and a better understanding of the principles and details of the invention will be evident from the following description taken in conjunction with the appended drawings, in which: FIG. 1 illustrates schematically a complete section of the riser pipe, from below the mudline up through the sea and up into the jacket of a vertically moored platform showing the type of curvature that is experienced. FIG. 2. illustrates a general design for a terminator. FIG. 3 illustrates the construction of a terminator and terminator extension of our invention, positioned inside a jacket leg with proper horizontal bearings. FIGS. 4 and 5 show schematically the arrangement of the terminator extensions respectively at the mudline, and inside the jacket leg. FIG. 6 illustrates an alternate embodiment of that shown in FIG. 3. FIG. 7 illustrates a combination horizontal and thrust bearing for positioning the terminator in the jacket leg. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT Referring now to the drawings and in particular to FIG. 1, there is shown a simple diagram of a vertically moored platform (VMP) indicated generally by the numeral 10 having a jacket leg 12 into which is inserted, through the bottom, a riser pipe 26 which is in effect a continuation of a pipe or casing 38 which is anchored below the mudline after passing through conductor casing 36. The bottom anchor of the riser pipe is such that it can support the tension which will be required to hold the vertically moored platform in position on the sea surface. At the point 22 there is a horizontal bearing for transmitting lateral or horizontal forces, and at point 14 there is a vertical bearing for transmission of axial forces. There are flexure zones 24 and 28 within the length of the riser pipe near the platform and the mud-line, respectively. The portion 26A between the flexure point is substantially straight but non-vertical, while the riser pipe is vertical in the earth and is vertical inside the platform leg. Thus bending is concentrated where the curvature is shown just below the platform leg and just above the well template 32 which rests on the mud surface 34. The object of the terminator is not only to anchor the riser pipe at the platform but also to design the anchor mechanism so as to properly provide the necessary curvature shown in FIG. 1 without stressing the pipe or terminator and other tubular members, that may be inside the riser, more than a selected maximum. FIG. 2 illustrates a typical prior art design of a terminator, which is joined at its two ends 42A and 42B, to riser pipes extending upwardly and downwardly. The terminator is designated generally by the numeral 40 and has a cylindrical portion 40D of selected length and diameter which tapers off through appropriate conical pipes 40E going down to the riser pipe, and various sections 40C, 40B, 40A, etc. going upwardly to the riser pipe. As shown on the drawing, the inner diameter and outer diameter vary throughout the length of the terminator, while one is constant the other varies and vice versa, or both vary simultaneously depending upon the most convenient way to design and construct the device. There is no precise dimension for the overall length of the terminator. It can have the two ends of equal length or have a longer portion in one direction, length L1, and a shorter portion of length L2 in the other direction. The reason that this is preferred is that in the end which is joined to pipe inside a containing pipe or sleeve, the amount of deflection that can be permitted is less than the other long end L1, where the pipe is in the water and has no lateral constraint. If the design were symmetrical about the anchor point 43, then the deflection would be symmetrical on each side of the point, and the design of the terminator would be symmetrical also. The mathematics for determining lateral deflection of a vertically suspended pipe are well known. The system can be described by the following beam column differential equation: ##EQU1## where: E(x)=modulus of elasticity, I(x)=moment of inertia, P(x)=axial load, y(x)=lateral deflection, and x=location along the length of the beam column. By applying the known boundary conditions of a system, the differential equation can be solved such as to satisfy all required conditions. Such required conditions can include stress level, lateral deflection limits, or structural section size and/or configuration. Referring now to FIG. 3, there is shown in schematic outline a construction of a novel multiterminator having a terminator indicated generally by the numeral 58 and a termination extension generally indicated by numeral 64. Terminator 58 has a short leg 59 and a long leg 60. The long leg is directed downwardly and joins a length of riser pipe 26. The mid section, which is preferably not in the center of the terminator, is held in a horizontal bearing 54. This horizontal bearing 54 provides a lateral restraint for the terminator 58. If the horizontal bearing 54 is modified as shown in FIGS. 6 or 7, it can also provide for axial force transmission. As previously indicated, the lengths of the short and long ends 59A and 60A preferably are not equal and may roughly be defined in a ratio of approximately 1:2. The overall length can vary depending on the size and dimensions of the pipes, etc., and the tension required. The terminator 58 is provided with horizontal support at the lower horizontal bearing 54 which will be discussed in connection with FIG. 7. The length of the terminator extension is indicated by the numeral 62 and is a portion of the assembly reaching from the point of horizontal bearing 54 of the terminator 58 to the point 66, above a second horizontal bearing 56. The length of the terminator 58 is indicated by 58A. A suitable horizontal bearing is shown in U.S. Pat. No. 4,130,995 entitled "VMP Riser Horizontal Bearing" issued on Dec. 26, 1978. Sleeve 50 forms an inner opening through the jacket leg 12 through which the riser pipe enters up into the drilling and producing portions of the platform. The top of the short leg 59 goes to a short length 26' of the riser pipe which is connected to a "short" or second terminator 63 that has a double-ended, substantially symmetrical, tapered section 64, which can be provided with a second horizontal bearing 56 inside sleeve 50. Riser pipe section 26' and short terminator 63 and terminator end 58 form what can be called a terminator extension 62. That portion of FIG. 3 indicated by sections 60A and 62 can be called a "multiterminator". The upper end 66 of the terminator extension is roughly set at the point where there is little or no bending moment in the pipe 26". The riser pipe 26" then extends through an optional vertical bearing 57, which permits sliding contact of very small amounts which occur as the curvature of the pipe 26 varies. However, since the motion of the pipe 26" through the vertical bearing 56 is very small, the construction can be simple friction contact. A suitable vertical bearing 57 can be such as shown in U.S. Pat. No. 4,127,005 entitled "Riser/Jacket Vertical Bearing Assembly for Vertically Moored Platform" issued Nov. 28, 1978. For the purposes of the following discussions, three bearings 54, 56 and 57 will be referred to, as well as two terminators 58 and 63; however, it should be understood that only two bearings are needed for the purposes of the present invention. That is, bearing 54 and 56 can be used, but bearing 57 is optional as design loads dictate its use. The use of bearing 56 and the second terminator 63 may not be needed, as shown in FIG. 6, if design loads dictate; however, it has been found for most applications the use of the two terminators and at least two bearings is preferable to provide the beneficial results described hereinbelow. Referring to FIGS. 4 and 5, FIG. 4 shows the lower end of the riser pipe as it is anchored to the conductor pipe 70, which is anchored in the earth 71. The principal terminator 58 with legs 60 and 59, are the same as illustrated in FIG. 3 and the section of riser pipe 26' and also the second terminator 64 and horizontal bearings 56 and 54 are all as shown in FIG. 3, except that at the lower end of the pipe, the terminator is inverted with respect to the upper end of the anchoring at the VMP or other floating structure. FIG. 5 is similar except that it is now in the same direction of installation as in FIG. 3, with the long leg 60 of the principal terminator pointed downwardly into the water, while the short end is connected through a section of riser pipe 26A and the short terminator 63 and the pipe 26B going up through the vertical bearing 57. The curved line 76 which passes through the center 86 of the lower horizontal bearing 54 and also through the center 88 of the upper horizontal bearing 56 would illustrate in an exaggerated fashion, the curvature of the structure of FIG. 5 when there is a deflection, for example, of the VMP to the left. The lower portion 75 of the curve is deflected to the right of the upper portion 76 of the curve as the jacket tends to move to the left. The terminator rotates, i.e., angularly deflects inside bearing 54. Again, the upper terminator 64 angularly deflects a small amount in its bearing 56 in a reverse direction with decreasing amplitude over the amplitude in the section between the two terminators. Thus the curvature would be greatest at the lower end 75, less on the top 77 of the lower 58 terminator and lower still 78 above the smaller terminator 64. The arrow 80 is shown as the direction of the force being applied by the platform to the riser pipe through the horizontal bearing 54. The lower portion of the riser pipe is anchored in the earth and the earth provides a restraining force 82. There is also a restraining force 89 applied above the lower terminator by a horizontal force applied at the upper bearing 56. Any type of bearing support 54 may be used between the upper terminator 63 and the platform leg, as previously mentioned, so long as it provides for a bending in any vertical plane through the leg of the jacket of the VMP. It is also necessary to provide a tension in the riser pipe below the lower bearing 54. A bearing of the type shown in FIG. 7 provides for transmission of both vertical and horizontal forces. The direction of portion 75 of the line 79 in FIG. 5 makes an angle 81 with the axis of sleeve 72. The direction of the line 79 above the lower bearing 54 makes an angle 83. The lower terminator 58 mid section angularly deflects about point 86 to be tangent to this curve. Angle 83 is smaller than 81. Again, the upper terminator 63 will rotate about point 88 to be tangent to the line 79 at 88. There will be a smaller deflection 78 of the pipe above the upper terminator. Thus, by providing the multiple terminators (there could be a third and fourth one above the top terminator 63, not shown), each in its own bearing 54, 56, a much greater deflection angle 81 can be provided without increasing the stress in the riser pipe. The first horizontal bearing 54 of FIG. 3 can be as shown in FIG. 7, which indicates a fixture 90 surrounding the pipe 58B which is the cylindrical center portion of the terminator 58. The fixture 90 has two rings, an upper ring 92, and a lower ring 94. Point 86 represents the center of the spherical portions. The horizontal bearing centerline 54A will pass through that center 86. The bearing elements are essentially an outer steel base ring 96 and an inner steel ring 98 supported by ring 92. Ring 98 is attached to ring 92 and its outer surface is spherical. The inner surface of the outer portion 96 which is attached to the sleeve 50 is also spherical and the center shell portion 100 is a resilient elastomeric compliant material, which is bonded to the spherical suriaces of the portions 98 and 96. Thus the two surfaces 98 and 96 have limited movement to rotate about the center 86 with respect to each other, while the inner material 100 moves in a shearing action, so that a substantially frictionless rotation is possible over a limited angle. The lower spherical bearing has an inner ring 98A and an outer ring 96A, with a corresponding intermediate portion 100A. This is an alternate means to provide the thrust transmission means required to maintain the tension in the riser pipe, but still permits the rotational feature controlled by the horizontal bearings 54. The bearing rings 98A, 96A, and 100A are supported on ring 94. The center of the spherical surfaces 98A, 96A is at point 86. While the success of the bearing, such as the one illustrated in FIG. 7, is important to the success of the entire anchoring system, including the terminator and the terminator extension; and while the design shown in FIG. 3 may be preferred, other designs can, of course, be used provided they meet all of the motion and stress requirements, and utilize flexibility of the terminator and terminator extension previously described. The upper horizontal bearing 56 of FIG. 5, which supports the upper terminator 63, is not required to take thrust. Therefore, bearing 56 may simply be the horizontal bearing portion 92 of the bearing assembly shown in FIG. 7. This would include the ring 92, the two spherical rings 98 and 96 and the compliant shell 100. Ring 98 has an outer surface which is spherical, centered at point 86. Ring 96 has an inner surface which is spherical, also centered at point 86. Point 86 is on the axis of the terminator and sleeve 50. It also lies on the central horizontal plane 54A through the rings 98, 96. The spherical surfaces of the rings 98 and 96 are spaced apart a selected distance, and this space is filled with a selected elastomeric material, which is preferably bonded to both spherical surfaces. The two portions of the bearing assembly lateral bearing 92 and thrust bearing 94 are mounted on a rigid internal pipe 58B, which comprises the cylindrical midsection of the principal terminator 58. The tubular members 91, shown by dashed lines, represent one of a plurality of casings which may lie in the annulus between the innermost casing or conductor pipe 93. These are all substantially co-axial pipes, and form another reason for limiting the maximum stress and deflection at all points along the riser pipe. We have shown in FIGS. 3 and 5 a complete set of bearings for the multiterminator or terminator extension of this invention. In FIG. 7 we have shown the thrust bearing 94 as a part of an assembly with one of the lateral bearings 92. However, it is equally possible to apply the thrust bearing widely spaced from the lateral bearings. With the thrust bearing widely spaced from the lateral bearings, a lateral bearing is required which has a combination of rotary and sliding motion. Such a bearing is illustrated in FIG. 5 of U.S. Pat. No. 4,130,995 which has a portion 48 which combines an outer cylindrical surface 82 with an inner spherical surface 56. Another embodiment of the present invention is shown in FIG. 6, wherein a terminator assembly is provided with only two bearings 54 and 57. In this embodiment, the first terminator 58 has its long leg 60 connected to a riser pipe 26 which extends up from the sea floor or downward from the sleeve 50. A bearing 57, either a horizontal or a combination of a horizontal and a vertical bearing, is spaced a certain distance up or down the riser 26". This distance is important because it should be of a length such that under maximum design loads the riser 26" and 26' will deflect or bend no more than to allow the riser to contact the interior wall of the sleeve 50. Depending upon the sleeve's 50 construction and structural support, the sleeve 50 can withstand some amount of force exerted on it by the riser. However, it is preferable that the distance between the bearing 57 and bearing 54 is such that under maximum design loads there will be no contact between the riser and the sleeve 50. We have described a multiterminator which is an improvement in the anchoring mechanism by which a riser pipe is attached in a vertical manner inside a jacket leg of a vertically moored platform or other floating structure. The same construction can also be utilized at the lower anchorage of the riser pipe with the earth. By the use of the terminator and terminator extension (multiterminator), it is possible to maintain a greater total angular deflection of the pipe without providing any greater maximum value of stress in the pipe at any point. The required length and weight of the prior art terminator and of the multiterminator of our invention were calculated using known tension beam equations for the following design conditions of an offshore location. Water depth--1000 feet Wind--130 knots Wave--90 feet maximum; 13.5 second period Current--4.4 feet/second Riser outside diameter--18.625 inches Riser wall thickness--0.625 inches Pre-tension per riser--600,000 pounds Pre-tension per riser--600,000 pounds Diameter of sleeve 50 in jacket leg through which riser passes--45 inches Diameter of piles or conductor pipes 70 in sea floor through which riser extends--40 inches Maximum allowable outer fiber stress--65,000 pounds/sq. in. The following table shows the results of our calculations comparing the length and weight of our multiterminator (as indicated in FIG. 3) and the prior art terminator (as indicated in FIG. 2) in which the outer fiber stress from the combined effects of axial tension and bending moment is equal to the maximum allowable value along the entire length of the terminator assembly. ______________________________________Length Length Weight Weight(Prior Art (Multi- (Prior art (Multi-terminator) terminator) terminator) terminator)______________________________________Upper Assembly176 ft. 106 ft. 83,300 lbs 42,700 lbsLower Assembly176 ft. 127 ft. 6 in. 127,000 lbs 90,800 lbs______________________________________ This reduction in overall length and total weight is most important. For example, these terminators will have to be manufactured at specially equipped fabrication centers and shipped and installed as a unit. The reduction in length and weight of multiterminators using our invention makes the offshore installation much more practical and in some cases permits installations which might otherwise be prohibited because of the size of terminator required under the prior art system. While we have described this invention as related to the vertically moored platform, for which it is admirably suited, it can also be used with other types of floating structure. While the invention has been described with a certain degree of particularity, it is manifest that many changes may be made in the details of construction and the arrangement of components without departing from the spirit and scope of this disclosure. It is understood that the invention is not limited to the exemplified embodiments set forth herein but is to be limited only by the scope of the attached claim or claims, including the full range of equivalency to which each element thereof is entitled.

This invention is an improvement over the simple riser pipe terminator, which has been applied at the mudline and at the platform level, to resist very large stresses in the riser pipes when a vertically moored platform (VMP) or other similarly tethered structure is subjected to wind, tide and current. A second or short terminator is used with the terminator to form a multiterminator which results in the length and weight of the terminator assembly for a given site being greatly reduced from that of the prior art terminator. Thus, the cost of construction of the terminator assembly is drastically reduced with the use of our invention. Also disclosed is a novel bearing arrangement between the structure VMP and the terminator assembly.

CROSS REFERENCE TO RELATED APPLCIATIONS [0001] This application is a continuation of U.S. application Ser. No. 09/617,793 filed Jul. 17, 2000. [0002] This application is related to concurrently filed U.S. application (Attorney Docket 31713-164687) which is a continuation of U.S. application Ser. No. 09/617,974. BACKGROUND OF THE INVENTION [0003] The invention relates to a method for stacking containers that have been shaped and punched from a sheet of thermoplastic plastic in a shaping tool, and guided to stack magazines, as defined in the preamble to the main claim. The invention further relates to an apparatus for executing the method. [0004] It is known to stack containers that have been shaped and punched from a sheet of thermoplastic plastic in stack magazines, and to remove the stacks from the stack magazines when a specific length or specific piece number is attained, then supply them to successive devices. In these successive devices, either processing takes place, such as bordering of the container edge, or the rods are packaged in foil and transferred to cartons. It is also known to shape the containers in a plurality of rows, with several containers per row, and to guide the stacks consecutively with a transfer device, so they pass through a single bordering station, for example. Stack magazines for receiving the total batch of containers shaped per cycle in the shaping tool are disposed in front of the shaping tool, which is pivoted into the transfer position. [0005] Transporting stacks of specific lengths out of the stack magazines stipulates a certain amount of time. During this time, the shaping tool must continue producing, and the containers must be able to be stacked. German utility model application DE 298 02 318 U 1 proposes to arrange a stationary stack magazine in the stacking station, and above it, a movable stack magazine, with the movable stack magazine being displaceable in both the stacking direction and the direction transverse thereto. The containers are first transferred into the stationary stack magazine, then enter the movable stack magazine after a specified stack height has been attained. [0006] German Patent DE-PS 26 48 563 C 2 likewise discloses transferring the containers into a stationary, lower stack magazine initially, then into a stack magazine that is adjustable in height and lifts a stack once it reaches a specific length or a specific number of containers. A lateral sliding element transfers these stacks to a horizontal receiving sheet. [0007] Handling stacks in this manner does not provide consecutive guidance of the stacks. They would have to be taken up again, a process that would be susceptible to disturbances. A disadvantage of the two cited publications is that, during the time in which the stacks are transferred from the stack magazines, the number of stacked containers depends on the cycle number of the shaping tool. The transfer time of the stacks is constant because of the established paths and speeds of the drives. This means, however, that a varying number of containers is shaped and stacked during this transfer time. This is significant, and is associated with control problems, if stacks are to be formed from a specific number of containers. A further drawback of the two stacking methods is that the containers must be pressed over two stacking edges, which always poses a risk of deformation. As the movable stack magazine returns, it must be pushed across the standing stacks, which can also cause deformation, because each container edge of the standing containers must be guided by these retaining elements. This method of gripping containers is highly susceptible to disturbances, which may necessitate shutting down the shaping machine, cleaning the stack magazines or organizing the containers located in the stack magazines. [0008] It is the object of the invention to execute the method in order to create stacks of a predetermined number of containers, regardless of the cycle number of the shaping tool, and independently of the time required for transferring the stacks to successive devices, even if the apparatus is shut down. The method is intended to be insusceptible to disturbances, and able to be executed even with high cycle numbers of the shaping tool. Furthermore, the method should permit the transfer of container stacks in rows to a successive device, and a fast changeover of the apparatus for a different batch of containers. SUMMARY OF THE INVENTION [0009] The above object generally is achieved according to a first aspect of the invention by a method for stacking containers that have been shaped and punched from a sheet of thermoplastic plastic in a shaping tool, and guided to stack magazines, and for transferring the stacks to a successive device, wherein the containers are transferred into a first stack magazine at a stacking station; after a predetermined number of containers per stack has been attained in the first stack magazine, the first stack magazine is displaced into a stack-removal station, and a second stack magazine is transferred out of the stack-removal station into the stacking station, between two cycles of the shaping tool; and while the containers are being stacked in the second stack magazine at the stacking station, the first stack magazine is emptied, and the removed stacks are guided to a successive device. [0010] The above object generally is achieved according to a second aspect of the invention by an apparatus for stacking containers that have been ejected from a shaping tool after being shaped and punched out with, for executing the method [0011] according to the invention wherein two stack magazines, which can be displaced between a stacking station and a [0012] stack-removal station are provided. [0013] The method is described in detail in conjunction with the schematic drawings of various embodiments of the apparatus. BRIEF DESCRIPTION OF THE DRAWINGS [0014] [0014]FIG. 1 is a side view of the apparatus according to the invention. [0015] [0015]FIG. 2 is a plan view of the apparatus according to the invention. [0016] [0016]FIGS. 3 and 4 are views in the direction X of FIG. 2 in two phases of the method for a first embodiment of the apparatus. [0017] [0017]FIG. 5 is a side view of a second embodiment of the apparatus according to the invention. [0018] [0018]FIGS. 6 and 7 are a side view and plan view, respectively, of a third embodiment of the apparatus according to the invention. [0019] [0019]FIG. 8 is a plan view of an apparatus according to a fourth embodiment of the invention. [0020] [0020]FIGS. 9 and 10 show a variation of the invention having pivotable and possibly traveling stack magazines. [0021] [0021]FIGS. 11 and 12 show a variation of the invention having a pallet belt. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS [0022] Referring now to FIG. 1, the apparatus for executing the method of the invention is disposed downstream of a thermoforming machine, which employs a shaping tool 1 to shape and punch containers 2 from a heated sheet 3 of thermoplastic plastic. In the illustrated examples, one half of the shaping tool 1 is embodied to pivot to a horizontal position, so that the containers 2 are ejected horizontally from the shaping tool 1 by, for example, push-rods. Other directions of ejection are also feasible for the method of the invention, such as with the pivoting of the shaping tool 1 by only 75 rather than 90° from the vertical. [0023] In an apparatus according to a first embodiment, as illustrated in FIGS. 1 through 4, a first stack magazine 4 is disposed sufficiently close to the opening of the pivoted shaping tool 1 that the containers 2 can be stacked directly in the magazine—this position is referred to as the stacking station 33 . Retaining elements retain the containers 2 in a known manner. The stack magazine 4 is adjustable in height, and can be lowered from the stacking station 33 (position A in FIG. 3) while a second stack magazine 5 is brought into position A. This movement occurs between two work cycles of the shaping tool 1 . The lowered stack magazine 4 can now be displaced horizontally by a motorized or pneumatic drive, not shown, by a distance greater than its structural width, until it reaches the position B in FIG. 3. The magazine is supported and guided by guides 6 . From this position B, the magazine is raised in stages into a stack-removal station 32 , where first the upper row of stacks 7 stops at the height of a transverse transport belt 8 having transverse supports 9 (position shown in FIG. 4). Sliding elements or push-rods 10 eject a row of stacks 7 onto the transport belt 8 . The transport belt 8 guides the stacks 7 —possibly via a further transport belt—to a site of further processing or handling. The stack magazine 4 is raised again, so the next row of stacks 7 can be ejected. With three-row stack magazines, the third stack row is cleared in the same manner. [0024] Once the stack magazine 4 has been emptied, it is lowered and guided back into the position A. It waits there until the predetermined number of containers 2 per stack 7 has been attained in the stack magazine 5 . Then, the stack magazines 4 and 5 are exchanged between two cycles of the shaping tool 1 , with the stack magazine 5 being raised into the position D and the stack magazine 4 assuming its stacking position. The stack magazine 5 can be adjusted in height by way of a drive, and displaced horizontally by way of a second drive, until it reaches the position E (FIG. 3), thereby being guided and supported by guides 11 . From the position E, the magazine is lowered in stages, so the individual stack rows can be guided in front of the transport belt 8 and ejected. [0025] After the stack magazine 5 has been emptied, it is transferred into the position D and kept ready for the next magazine exchange, so the exchange can be performed very quickly with a short travel path. The arrows 12 , 13 illustrate the directions of movement of the two stack magazines 4 , 5 . [0026] This method permits all of the containers 2 to be stacked directly, without a further transfer, in stack magazines 4 , 5 , and permits counted stacks 7 to be produced simply. The apparatus can be reset simply for a different container shape through an exchange of the two stack magazines 4 , 5 and a programming of the stroke required for clearing the individual stack rows. This can be done quickly and simply. With this method, the containers are not subjected to any large movements in the free atmosphere, which could cause the growth of microorganisms on the container surface. [0027] [0027]FIG. 5 illustrates an expansion of the stacking method, in which the containers 2 are rotated by 180° prior to stacking; that is, they are pushed bottom-first into the stack magazines 4 , 5 . This is particularly advantageous for stack formation and the further guidance of the stacks to successive devices. In this case, a turning device 14 is disposed, as a transfer device, between the tipped shaping tool 1 and the stack magazines 4 , 5 . The turning device takes up the ejected containers 2 via of a suction plate 15 , possibly having centering arbors 16 , then rotates the containers and transfers them into the stack magazines 4 , 5 , which, in this embodiment, are disposed to be displaced in the same manner—only at a distance from the shaping tool 1 . [0028] A variation of the method that is described in conjunction with the apparatus according to FIGS. 6 and 7 permits an improved accessibility of the shaping tool 1 , e.g., for exchanging, cleaning and observing it. Also in this case, the ejected containers 2 are transferred to a transfer device in the form of a retaining or vacuum plate 15 , which can be displaced transversely on guides 16 , until it is in front of a stack magazine 17 , into which the containers 2 are transferred. This transfer is effected by a relative movement between the stack magazine 17 and the retaining plate 15 by way of a drive, not shown, which operates at the stack magazine 17 or the retaining plate 15 . This stack magazine 17 can be exchanged with a stack magazine 18 in the manner illustrated in FIG. 3. The stacks 7 are ejected in the same way, by means of an ejection device 19 , onto a transport belt 20 and possibly onto a further transport belt 21 . [0029] In an apparatus according to FIG. 8, the method is modified such that the containers 2 are transferred alternatingly in two directions by means of two retaining plates 22 , 23 . The retaining plate 22 guides the containers 2 on one side to a stacking station 33 with the stack magazines 24 , 25 (as indicated by the dotted illustration of the plate 22 ), while the other retaining plate 23 guides them to a second stacking station 33 with the stack magazines 26 , 27 . Thus, two ejection devices 28 , 29 and two transport belts 30 , 31 are used. The stack magazines 24 , 25 and 26 , 27 are exchanged as described above. [0030] This method offers the additional advantage that it can be used with very high cycle numbers of the shaping tool 1 if a cycle time in the order of magnitude of 1.5 seconds is insufficient to guide the containers 2 that have been taken up by the transfer device to a lateral stacking station 33 , and back in front of the shaping tool 1 . [0031] In the examples illustrated in FIGS. 1 through 8, the stacking is effected horizontally from the shaping tool. If the process is effected at a diagonal, as shown in FIGS. 9 and 10, it can be advantageous to pivot the stack magazines 34 disposed in the stack-removal station 32 into the horizontal position, as shown in FIG. 9, before the stacks 7 are ejected, and possibly move the magazines in the stacking direction, as indicated in FIG. 10, so they lie in front of a transverse conveyor belt 35 . [0032] [0032]FIGS. 11 and 12 illustrate a modification of the method in which, prior to stacking, the containers 2 are transferred into a circulating pallet belt 36 having pallets 37 that are provided with holes. From these pallets, the containers are transferred into the vertical stack magazines 38 , 39 , which are alternatingly guided via a pallet 37 , and thus into a stacking station 33 , beneath which an ejection device 42 is disposed. These figures illustrate, by way of example, that the stack magazines 38 , 39 are guided from the stacking station 33 to two stack-removal stations 32 , so after the stack magazines 38 , 39 have been raised and tipped in this stack-removal station 32 , the stacks 7 are guided onto two transport belts 40 , 41 . The stacks 7 can be transported out in rows by a stack-removal device 43 through a corresponding lowering of the stack magazines 38 , 39 . It is also possible in the same manner, however, to guide the two stack magazines 38 , 39 to a single stack-removal station 32 , as in the other embodiments, through a corresponding U-shaped movement of the two stack magazines 38 , 39 . [0033] The invention now being fully described, it will be apparent to ne of ordinary skill in the art that many changes and modifications can be made thereto without departing from the spirit or scope of the invention as set forth herein.

A method to improve the stacking of containers comprising thermoplastic plastic, and the transfer of the stacks to a successive device. Stacks of a predetermined number are intended to be produced without disturbances, even with a high cycle number of the shaping tool. This is achieved in that the containers are stacked in a first stack magazine, which is exchanged for an adjacent stack magazine between two cycles of the shaping tool after the predetermined number has been reached. The containers are stacked in the stack magazines directly from the shaping tool, or by an intermediate transfer device.

[0001] This application claims the benefit of Japanese Application No. 2001-21491 filed in Japan on Jan. 30, 2001, the contents of which are incorporated by this reference. BACKGROUND OF THE INVENTION [0002] The present invention relates generally to an image pickup system such as a silver-salt or digital camera, and more particularly to an image pickup system comprising an electronic view finder suitable for use with a compact image display device, especially a reflection type liquid crystal display device. [0003] Most of silver-salt or digital cameras comprise means for recording images picked up by an image pickup optical system and a viewing optical system for checking an image pickup range. For the recording of images, chemistries on film surfaces are used in the case of silver-salt cameras, and information obtained through photoelectric conversion at electronic image pickup devices such as CCDs are employed in the case of digital cameras. [0004] On the other hand, most of viewing optical systems are of the type designed to form an image on the retina of a viewer's eye, thereby viewing the image to be picked up. This type of viewing optical system does or does not comprise an image pickup optical system for forming an image to record a part of the entrance side. A typical example of the former is a single-lens reflex camera, and that of the latter is a real image type finder suitable for use on a zoom optical system, including an objective optical system, an image-erecting means and an eyepiece optical system and now mounted on most products. These are often collectively called an optical finder. [0005] In many cases, digital cameras or video cameras are put on the market while they are provided thereon with an electronic finder designed to display an image on an LCD (liquid crystal display device) rather than an optical finder, so that the image pickup range can be checked by allowing an observer to have a direct view of the image. Digital cameras with both an optical finder and an electronic finder mounted thereon, too, are now commercialized. [0006] Furthermore, the so-called EVF (electronic view finder) designed to view images on LCDs via a viewing optical system is proposed. For conventional commodities with such an electronic finder mounted thereon, there is used a display device with a display screen having a diagonal length of about 0.5 inches or 12 mm. [0007] However, there are growing demands for size reductions of cameras. The associated viewing optical system has been designed in conformity with conventional LCD size; the whole size of the viewing optical system cannot be reduced or some limitations are placed on further size reductions of image pickup systems. [0008] Meanwhile, some LCDs have been developed with size smaller than so far achieved. However, when such LCDs are used with an electronic view finder, existing viewing optical systems offer a problem that the angle of field for viewing subjects becomes small depending on LCD size so that satisfactory observation becomes difficult. [0009] Further, as the whole size of a viewing optical system is reduced in conformity with LCD size, some inconveniences such as failures in obtaining the eye relief necessary for observation are unavoidable. [0010] Furthermore, as the magnification of the viewing optical system increases with decreasing image display device size, not only is chromatic aberration of magnification likely to occur but there is also a problem that dust, etc. deposited on the viewing optical system is visible on an enlarged scale. [0011] To add to this, when a reflection type display device with light rays incident on its display screen side is used as the image display device, it is required to get hold of the separate optical path necessary for display purposes. SUMMARY OF THE INVENTION [0012] In view of such problems as mentioned in conjunction with the prior art, the present invention has been accomplished to achieve any one of the following objects. [0013] One object of the invention is to provide an image pickup system with an electronic view finder mounted thereon, which is suitable for achieving compactness. [0014] Another object of the invention is to provide an image pickup system that allows viewers to have an easy grasp of an image pickup range. [0015] Yet another object of the invention is to provide an image pickup system that ensures a sufficient viewing angle of field and satisfactory optical performance even when used with an image display device having a short diagonal length of its display surface. [0016] Still yet another object of the invention is to provide an image pickup system having an electronic view finder well corrected for chromatic aberration of magnification. [0017] A further object of the invention is to provide an image pickup system having an electronic view finder, where dust, etc., if deposited on a viewing optical system, are virtually unnoticeable, [0018] A further object of the invention is to provide an image pickup system with an electronic view finder mounted thereon, which enables optical elements to be appropriately located even when a reflection type image display device is used as an image display device. [0019] A further object of the invention is to provide an image pickup system having an electronic view finder capable of accomplishing a plurality of such objects as mentioned above. [0020] According to the first aspect of the invention, there is provided an image pickup system comprising an image pickup device, an image display device for displaying an image, a controller for converting image formation obtained from said image pickup device into a signal that enables said image information to be formed on said image display device, and a viewing optical system for guiding an image displayed on said display device to a viewer's eye, characterized in that: [0021] said viewing optical system comprises at least three lens elements, at least two of which are cemented together to form a doublet component. [0022] An account is now given of what is achieved by the first image pickup system. [0023] To achieve the necessary angle of field (of, e.g., 22°) at the diagonal length of the display screen of an image display device in a conventional image pickup system, an eyepiece magnification of around 7 would be plenty good enough. However, to obtain a sufficient angle of field in the case where a smaller image pickup device is used, too, it is required for a viewing optical system to have a higher eyepiece magnification than a conventional one. To ensure a sufficient angle of field and satisfactory optical performance even when such a smaller image display device is used, therefore, it is required to use at least three lenses for the viewing optical system. This then enables the number of refracting surfaces to be so increased that any sharp refraction by refracting surfaces can be prevented, resulting in a sensible tradeoff between correction of aberrations and ensuring the necessary angle of field. [0024] A lens arrangement consisting of two positive lenses and one negative lens or three lenses in all is more preferable in consideration of cost, because chromatic aberrations and other aberrations can be corrected with a reduced number of lenses. [0025] The doublet component is not only effective for correction of chromatic aberrations but can also have a larger thickness as compared with a lens arrangement comprising separate single lenses. It is thus possible to reduce lens tilt errors on assembly. It is here noted that when the image pickup optical system used is of an interchangeable type, the present invention also includes an image pickup system proper alone. [0026] According to the second aspect of the invention, the image pickup system of the first aspect is further characterized in that said viewing optical system comprises two positive lens elements and one negative lens element. [0027] What is achieved by the second image pickup system is now explained. [0028] With the positive lenses and negative lens incorporated in the viewing optical system, it is possible to make correction for a variety of aberrations inclusive of chromatic aberration of magnification. With the use of at least two positive lenses, positive power can be dispersed throughout the viewing optical system so that spherical aberrations liable to occur with increasing magnification can be well corrected. [0029] According to the third aspect of the invention, the image pickup system of the second aspect is further characterized in that one of said at least two positive lens elements is cemented together with said one negative lens element to form said doublet component. [0030] What is achieved by the third image pickup system is now explained. [0031] Chromatic aberration of magnification likely to occur when the magnification of the viewing optical system becomes high can be well corrected with the doublet. [0032] According to the fourth aspect of the invention, the image pickup system of the third aspect is further characterized-in that at least one lens element different from said doublet component in said viewing optical system is a lens element having an aspheric surface. [0033] What is achieved by the fourth image pickup system is now explained. [0034] When an aspheric lens is used in a doublet, it is required to meet both cementing precision and aspheric precision. However, if an aspheric surface is used for one single lens, it is then possible to improve yield with cost reductions. It is here noted that the action of positive power becomes strong at the marginal region of the doublet. By using the aspheric surface at the surface spaced away form the doublet, it is thus possible to make well-balanced correction for axial to off-axis aberrations occurring at the doublet. [0035] According to the fifth aspect of the invention, the image pickup system of the fourth aspect is further characterized in that said lens element having an aspheric surface is a plastic lens element. [0036] An account is now given of what is achieved by the fifth image pickup system. [0037] By forming the lens with an aspheric surface using a plastic material, it is possible to improve processability. [0038] According to the sixth aspect of the invention, the image pickup system of the second aspect is further characterized in that at least one of said two positive elements is a lens element having an aspheric surface. [0039] What is achieved with the sixth image pickup system of the invention is now explained. [0040] It is preferable to use the aspheric surface in the positive lens, because cost reductions are achieved. [0041] According to the seventh aspect of the invention, the image pickup system of the firth aspect is further characterized in that said viewing optical system has an aspheric lens surface. [0042] An account is now given of what is achieved by the seventh image pickup system of the invention. [0043] As the magnification of the viewing optical system becomes high, off-axis aberrations are likely to occur. By the incorporation of an aspheric surface, however, it is possible to make well-balanced correction for axial to off-axis aberrations. [0044] According to the eighth aspect of the invention, the image pickup system of the first aspect is further characterized in that said viewing optical system consists of two lens components or a doublet component composed of one negative lens element and one positive lens element and one single-lens component whose absolute value for refracting power is smaller than either one of the absolute value for refracting power of said positive lens element and the absolute value for refracting power of said negative lens element. [0045] According to the ninth aspect of the invention, the image pickup system of the first aspect is further characterized in that said viewing optical system comprises a single-lens element having an aspheric surface. [0046] Reference is here made to what is achieved by the eighth and ninth image pickup systems of the invention. [0047] Main power for the viewing optical system is allocated to the doublet so that aberrations from axial to off-axis ones are well balanced by the single lens. This single lens, because its optical power can be reduced, also makes it easy to form an aspheric surface thereon, so that a reasonable tradeoff can be made between the number of lenses and correction of aberrations as well as processability. [0048] According to the tenth aspect of the invention, the image pickup system of the ninth aspect is further characterized in that said single-lens component has positive refracting power. [0049] Reference is now made to what is achieved by the tenth image pickup system of the invention. [0050] By using the single lens in the form of a positive lens, it is further possible to make satisfactory correction for spherical aberrations, etc. likely to occur at a viewing optical system of high magnification. [0051] According to the eleventh aspect of the invention, there is provided an image pickup system of the first aspect, characterized in that said viewing optical system consists of three lens elements or, in order from said image display device side, a positive lens element, a negative lens element and a positive lens element, while the first-mentioned positive lens element is cemented together with said negative lens element. [0052] An account is now given of what is achieved by the 11th image pickup system. [0053] Power is almost symmetrically allocated in +−+ order from the display device side, so that a variety of aberrations inclusive of spherical aberrations can be well corrected. A cemented surface for correction of chromatic aberration of magnification can be defined by cementing the positive lens on the display device side together with the negative lens. [0054] Further, main power is allocated on the display device side by locating the doublet on the display device side, so that the display device is located far away from the viewing optical system. This keeps diopter with respect to dust, etc. deposited on the viewing optical system remote from diopter with respect to the display screen, eliminating the inconvenience due to dust. [0055] Furthermore, it is easy to save space for the provision of a reflecting surface for guiding to the display screen the illumination light that is necessary when a reflection type image display device is used as the image display device. [0056] According to the twelfth aspect of the invention, the image pickup system of the first aspect is further characterized in that said viewing optical system consists of three lenses or, in order from said image display device side, a positive lens element, a positive lens element and a negative lens element, while the second-mentioned positive lens element and said negative lens element are cemented together. [0057] What is achieved by the 12th image pickup system is now explained. [0058] The principal point is shifted by allocating power in ++− order from the display device side, so that the display device is located far away from the viewing optical system. This keeps diopter with respect to dust, etc. deposited on the viewing optical system remote from diopter with respect to the display screen, eliminating the inconvenience due to dust. [0059] Further, a cemented surface for correction of chromatic aberration of magnification is defined by cementing together the positive lens on the viewer side and the negative lens. [0060] Furthermore, it is easy to save space for the provision of a reflecting surface for guiding to the display screen the illumination light that is necessary when a reflection type image display device is used as the image display device. [0061] According to the thirteenth aspect of the invention, the image pickup system of any one of the 1st, 8th, 9th, 11th and 12th aspects is further characterized by satisfying the following condition (1): 1.0 <b/a   (1) Here the small letter a is a distance from the display screen of the image pickup device to the surface, nearest to the image display device side, of the viewing optical system, and the small letter b is a total length from the surface, axially nearest to the image display device side, of the viewing optical system to the surface thereof nearest to the viewer side. [0062] What is achieved by the 13th aspect of the invention is now described. [0063] Condition (1) is provided to balance the distance from the display screen to the viewing optical system with the total length of the viewing optical system. To obtain a large angle of field with a image display device of small size, it is required to keep the focal length of the viewing optical system short. However, as the lower limit of 1.0 to condition (1) is not reached or the total length of the viewing optical system becomes short, it is required to increase the angle of refraction of axial and off-axis light rays through the viewing optical system, resulting in spherical aberrations, coma, chromatic aberration of magnification, etc. being likely to occur. Otherwise, the distance from the display screen to the viewing optical system becomes too long to obtain the necessary angle of field. To reduce the whole size of the electronic view finder, it is preferable to meet the following condition (1-1): 1.0 <b/a <3.5  (1-1) [0064] The same as mentioned-above goes true for the lower limit of 1.0 to this condition (1-1). As the upper limit of 3.5 is exceeded, it is difficult to achieve compactness even when a smaller image display device is used, because the total length of the viewing optical system becomes too long. Otherwise, the spacing between the display screen and the viewing optical system becomes short; dust deposited on the viewing optical system is more noticeable. In addition, it is difficult to take an optical path for guiding illumination light when a reflection type image display device is used as the image display device. [0065] More preferably, the following condition (1-2) should be satisfied: 1.5 <b/a <3.0  (1-2) [0066] According to the fourteenth aspect of the invention, the image pickup system of any one of the 1st, 8th, 9th, 11th and 12th aspects is further characterized by satisfying the following condition (2): 1.0 <a/c   (2) Here the small letter a is the distance from the display screen of the image pickup device to the surface, nearest to the image display device side, of the viewing optical system, and the small letter c is a length of the short side of the display screen of the image display device. [0067] What is achieved by the 14th image pickup system is now referred to. [0068] Condition (2) is provided to define the length from the display screen to the viewing optical system with respect to the length of the short side of the display screen. As the lower limit of 1.0 to condition (2) is not reached, dust deposited on the viewing optical system is more noticeable. In addition, when a reflection type image display device is used, it is impossible to take any reflection optical path for guiding illumination light thereto. [0069] To reduce the whole size of the electronic view finder, it is preferable to meet the following condition (2-1): 1.0 <a/c <4.5  (2-1) [0070] The same as set forth above holds for the lower limit of 1.0 to this condition (2-1). As the upper limit of 4.5 is exceeded, any compactness is never achievable even with a smaller image display device, because the spacing between the image display device and the viewing optical system becomes too large. [0071] More preferably, the following condition should be satisfied: 2.0 <a/c <4.0  (2-2) [0072] According to the fifteenth aspect of the invention, the image pickup system of any one of the 1st, 8th, 9th, 11th and 12th aspects is further characterized by satisfying the following condition (3): 1.4 <f e /a <2.4  (3) Here the small letter a is the distance from the display screen of the image pickup device to the surface, nearest to the image display device side, of the viewing optical system, and f e is a focal length of the viewing optical system. [0073] What is achieved by the 15th image pickup system is now described. [0074] Condition (3) is provided for the sufficient spacing between the display device and the viewing optical system as well as for the necessary eye relief. As the lower limit of 1.4 is not reached, it is difficult to take the eye relief necessary for observation. As the upper limit of 2.4 is exceeded, on the other hand, it is difficult to take any angle of field plenty enough for observation. [0075] More preferably, the following condition (3-1) should be met: 1.6 <f e /a <2.5  (3-1) [0076] According to the sixteenth aspect of the invention, there is provided an image pickup system comprising an image pickup device, an image display device for displaying an image, a controller for converting image formation obtained from said image pickup device into a signal that enables said image information to be formed on said image display device, and a viewing optical system for guiding an image displayed on said display device to a viewer's eye, characterized in that: [0077] said viewing optical system comprises at least three lens elements, and the following conditions (1) and (3) are satisfied: 1.0 <b/a   (1) 1.4 <f e /a <2.4  (3) Here the small letter a is a distance from the display screen of the image pickup device to the surface, nearest to the image display device side, of the viewing optical system, the small letter b is a total length from the surface, axially nearest to the image display device side, of the viewing optical system to the surface thereof nearest to the viewer side, and f e is a focal length of the viewing optical system. [0078] Referring to what is achieved by the 16th image pickup system of the invention, the actions obtained by meeting condition (1) for the 3rd image pickup system and condition (3) for the 15th image pickup system are attained in addition to those of the 1st image pickup system. [0079] Thus, condition (1) is provided to balance the distance from the display screen to the viewing optical system with the total length of the viewing optical system. To obtain a large angle of field with a compact image display device, it is required to keep the focal length of the viewing optical system short. However, as the lower limit of 1.0 to condition (1) is not reached or the total length of the viewing optical system becomes short, it is required to increase the angle of refraction of axial and off-axis light rays through the viewing optical system, resulting in spherical aberrations, coma, chromatic aberration of magnification, etc. being likely to occur. Otherwise, the distance from the display screen to the viewing optical system becomes too long to obtain the necessary angle of field. To reduce the whole size of the electronic view finder, it is preferable to meet the following condition (1-1): 1.0 <b/a <3.5  (1-1) [0080] The same as mentioned above goes true for the lower limit of 1.0 to this condition (1-1). As the upper limit of 3.5 is exceeded, it is difficult to achieve compactness even when a more compact image display device is used, because the total length of the viewing optical system becomes too long. Otherwise, the spacing between the display screen and the viewing optical system becomes short; dust deposited on the viewing optical system is more noticeable. In addition, it is difficult to take an optical path for guiding illumination light when a reflection type image display device is used as the image display device. [0081] More preferably, the following condition (1-2) should be satisfied: 1.5 <b/a <3.0  (1-2) [0082] Condition (3) is provided for the sufficient spacing between the display device and the viewing optical system as well as for the necessary eye relief. As the lower limit of 1.4 is not reached, it is difficult to take the eye relief necessary for observation. As the upper limit of 2.4 is exceeded, on the other hand, it is difficult to take any angle of field plenty enough for observation. [0083] More preferably, the following condition (3-1) should be met: 1.6 <f e /a <2.5  (3-1) [0084] According to the seventeenth aspect of the invention, the image pickup system of the 16th aspect is further characterized in that said viewing optical system comprises two positive lens elements and one negative lens element. [0085] No account is given of what is achieved by the 17th image pickup system because the same as referred to in conjunction with the 2nd image pickup system is achieved. [0086] According to the eighteenth aspect of the invention, the image pickup system of the 16th aspect is further characterized in that said viewing optical system has an aspheric lens surface. [0087] No account is given of what is achieved by the 18th image pickup system because the same as referred to in conjunction with the 7th image pickup system is achieved. [0088] According to the nineteenth aspect of the invention, the image pickup system of the 18th aspect is further characterized in that said lens element having an aspheric surface is a plastic lens element. [0089] No account is given of what is achieved by the 19th image pickup system because the same as referred to in conjunction with the 5th image pickup system is achieved. [0090] According to the 20th aspect of the invention, the 16th image pickup system is further characterized in that said viewing optical system consists of two lens components or a doublet component composed of one negative lens element and one positive lens element and one single-lens component whose absolute value for refracting power is smaller than either one of the absolute value for refracting power of said positive lens element and the absolute value for refracting power of said negative lens element. [0091] No account is given of what is achieved by the 20th image pickup system because the same as set forth in conjunction with the 8th image pickup system is achieved. [0092] According to the 21st aspect of the invention, the 16th image pickup system is further characterized in that said viewing optical system comprises a single-lens component having an aspheric surface. [0093] No account is given of what is achieved by the 21st image pickup system because the same as set forth in conjunction with the 9th image pickup system is achieved. [0094] According to the 22nd aspect of the invention, the 16th image pickup system is further characterized in that said viewing optical system consists of three lens elements or, in order from said image display device side, a positive lens element, a negative lens element and a positive lens element, while the first-mentioned positive lens element is cemented together with said negative lens element. [0095] No account is given of what is achieved by the 22nd image pickup system because the same as set forth in conjunction with the 11th image pickup system is achieved. [0096] According to the 23rd aspect of the invention, the 16th image pickup system is further characterized in that said viewing optical system consists of three lenses or, in order from said image display device side, a positive lens element, a positive lens element and a negative lens element, while the first-mentioned positive lens element and said negative lens element are cemented together. [0097] No account is given of what is achieved by the 23rd image pickup system because the same as set forth in conjunction with the 12th image pickup system is achieved. [0098] According to the 24th aspect of the invention, there is provided an image pickup system comprising an image pickup device, an image display device for displaying an image, a controller for converting image formation obtained from said image pickup device into a signal that enables said image information to be formed on said image display device, and a viewing optical system for guiding an image displayed on said display device to a viewer's eye, characterized in that: [0099] said viewing optical system consists of, in order from said image pickup device side, a negative single-lens component composed of one negative lens element and a positive single-lens component composed of one positive lens element, and the following condition (1)′ is satisfied: 0.6 <b/a   (1)′ Here the small letter a is a distance from the display screen of the image pickup device to the surface, nearest to the image display device side, of the viewing optical system, and the small letter b is a total length from the surface, axially nearest to the image display device side, of the viewing optical system to the surface thereof nearest to the viewer side. [0100] What is achieved by the 24th image pickup system is now explained. [0101] To obtain a sufficient angle of field, the viewing optical system must have a higher eyepiece magnification than a conventional one even when an image pickup device of small size is used. To ensure a sufficient angle of field with two lenses even when an image pickup system of small size is used, therefore, the viewing optical system must be composed of, in order from the image pickup device, a negative single lens and, a positive single lens. As a result, it is possible to spread out light rays with the negative single lens and guide the light rays to a viewer's eyeball through the positive single lens, thereby securing the necessary angle of field. [0102] When the viewing optical system is constructed of two lenses, the lens surface is spaced away from the image plane. This is preferable for preventing an image being observed from becoming worse due to the deposition of dust. For this reason, condition (1)′ is broader than condition (1). As the lower limit of 0.6 to condition (1)′ is not reached or the whole length of the viewing optical system becomes short, it is required to increase the angle of refraction of axial and off-axis light rays through the viewing optical system, resulting in aberrations such as spherical aberrations, coma and chromatic aberration of magnification being likely to occur. Otherwise, the distance from the display screen to the viewing optical system becomes too long to obtain the necessary angle of field. As a matter of course, the lower limit to this condition (1)′ may be set at 1.0 as in the case of condition (1). To reduce the whole size of the electronic view finder, it is preferable to meet the following condition (1-1): 1.0 <b/a <3.5  (1-1) [0103] The same as mentioned above goes true for the lower limit of 1.0 to this condition (1-1). As the upper limit of 3.5 is exceeded, it is difficult to achieve compactness even when a more compact image display device is used, because the total length of the viewing optical system becomes too long. Otherwise, the spacing between the display screen and the viewing optical system becomes short; dust deposited on the viewing optical system is more noticeable. In addition, it is difficult to take an optical path for guiding illumination light when a reflection type image display device is used as the image display device. [0104] More preferably, the following condition (1-2) should be satisfied: 1.5 <b/a <3.0  (1-2) [0105] According to the 25th aspect of the invention, the 24th image pickup system is further characterized by satisfying the following condition (2): 1.0 <a/c   (2) Here the small letter a is the distance from the display screen of the image pickup device to the surface, nearest to the image display device side, of the viewing optical system, and the small letter c is a length of the short side of the display screen of the image display device. [0106] What is achieved by the 25th image pickup system is now referred to. [0107] Condition (2) is provided to define the length from the display screen to the viewing optical system with respect to the length of the short side of the display screen. As the lower limit of 1.0 to condition (2) is not reached, dust deposited on the viewing optical system is more noticeable. In addition, when a reflection type image display device is used, it is impossible to take any reflection optical path for guiding illumination light thereto. [0108] To reduce the whole size of the electronic view finder, it is preferable to meet the following condition (2-1): 1.0 <a/c <4.5  (2-1) [0109] The same as set forth above holds for the lower limit of 1.0 to this condition (2-1). As the upper limit of 4.5 is exceeded, any compactness is never achievable even with a more compact image display device, because the spacing between the image display device and the viewing optical system becomes too large. [0110] More preferably, the following condition (2-2) should be satisfied: 2.0 <a/c <4.0  (2-2) [0111] According to the 26th aspect of the invention, there is provided an image pickup system comprising an image pickup device, an image display device for displaying an image, a controller for converting image formation obtained from said image pickup device into a signal that enables said image information to be formed on said image display device, and a viewing optical system for guiding an image displayed on said display device to a viewer's eye, characterized in that: [0112] said viewing optical system consists of, in order from said image pickup device side, a negative single-lens component composed of one negative lens element and a positive single-lens component composed of one positive lens element, [0113] said negative lens element is a double-concave lens element, [0114] said positive lens element is a double-convex lens element, [0115] of said negative lens element and said positive lens element, only said positive lens element has an aspheric surface, [0116] a light beam from said image display device is guided by refraction alone to said viewer's eye, and the following condition (2) is satisfied: 1.0 <a/c   (2) Here the small letter a is a distance from the display screen of the image pickup device to the surface, nearest to the image display device side, of the viewing optical system, and the small letter c is a length of the short side of the display screen of the image display device. [0117] What is achieved by the 26th image pickup system is now explained. [0118] To obtain a sufficient angle of field, the viewing optical system must have a higher eyepiece magnification than a conventional viewing optical system even when an image pickup device of small size is used. To ensure a sufficient angle of field with two lenses even when an image pickup system of small size is used, therefore, the viewing optical system must be composed of, in order from the image pickup device, a negative single lens and a positive single lens. As a result, it is possible to spread out light rays with the negative single lens and guide the light rays to a viewer's eyeball through the positive single lens, thereby securing the necessary angle of field. [0119] Condition (2) is provided to define the length from the display screen to the viewing optical system with respect to the length of the short side of the display screen. As the lower limit of 1.0 to condition (2) is not reached, dust deposited on the viewing optical system is more noticeable. In addition, when a reflection type image display device is used, it is impossible to take any reflection optical path for guiding illumination light thereto. [0120] To reduce the whole size of the electronic view finder, it is preferable to meet the following condition (2-1): 1.0 <a/c <4.5  (2-1) [0121] The same as set forth above holds for the lower limit of 1.0 to this condition (2-1). As the upper limit of 4.5 is exceeded, any compactness is never achievable even with a more compact image display device, because the spacing between the image display device and the viewing optical system becomes too large. [0122] More preferably, the following condition (2-2) should be satisfied: 2.0 <a/c <4.0  (2-2) [0123] Especially for correction of aberrations, it is preferable to use a double-concave lens for the negative single lens and a double-convex lens for the positive single lens, because the refracting power loaded on each lens can be allocated to both surfaces of each lens. In addition, as the light beam from the image display device is designed to be guided by refraction alone to the viewer's eyeball, the image under observation is lesser likely to become worse as compared with the provision of a reflecting surface, because of no tilt due to the reflecting surface. [0124] According to the 27th aspect of the invention, the 26th image pickup system is further characterized by satisfying the following condition (1): 1.0 <b/a   (1) Here the small letter a is a distance from the display screen of the image pickup device to the surface, nearest to the image display device side, of the viewing optical system, and the small letter b is a total length from the surface, axially nearest to the image display device side, of the viewing optical system to the surface nearest to the viewer side. [0125] No account is given of what is achieved by the 27th image pickup system because the same as set forth in conjunction with the 13th image pickup system. [0126] According to the 28th aspect of the invention, the 24th, 25th, 26th or 27th image pickup system is further characterized by satisfying the following condition (3): 1.4 <f e /a <2.4  (3) Here the small letter a is the distance from the display screen of the image pickup device to the surface, nearest to the image display device side, of the viewing optical system, and f e is the focal length of the viewing optical system. [0127] No account is given of what is achieved by the 28th image pickup system because the same as set forth in conjunction with the 15th image pickup system is achieved. [0128] According to the 29th aspect of the invention, there is provided an image pickup system comprising an image pickup device, an image display device for displaying an image, a controller for converting image formation obtained from said image pickup device into a signal that enables said image information to be formed on said image display device, and a viewing optical system for guiding an image displayed on said display device to a viewer's eye, characterized in that: [0129] said image display device has a display screen with a diagonal length in the range of 2.5 mm to 8 mm. [0130] What is achieved by the 29th image pickup system is now explained. [0131] Preferably in this aspect, the image display device should have a display screen with a diagonal length in the range of 2.5 mm to 8 mm. As the lower limit of 2.5 mm is not reached, any angle of field necessary for observation is hardly obtained. As the upper limit of 8 mm is exceeded, the effect on reductions in the whole size of the electronic view finder becomes slender. [0132] According to the 30th aspect of the invention, the 29th image pickup system is further characterized in that said viewing optical system comprises at least a lens element or at most three lens elements. [0133] An account is given of what is achieved by the 30th image pickup system. [0134] The incorporation of at least a lens element enables the viewing optical system to work through at least two refracting surfaces. The incorporation of at most three lens elements, on the other hand, keeps the viewing optical system from being composed of lenses more than required, resulting is some significant cost reductions. In addition, the incorporation of three lens elements in the viewing optical system is preferable for correction of aberrations. To meet both requirements for cost and correction of aberrations, the viewing optical system should preferably be constructed of three lens elements. [0135] According to the 31st aspect of the invention, the 29th image pickup system is further characterized in that the angle of field in a diagonal direction of an image being observed through said viewing optical system is in the range of 15° to 30°. [0136] What is achieved by the 31st image pickup system is now explained. [0137] The angle of field in the diagonal direction of the image being observed through the viewing optical system should be in the range of 15° to 30°. As the lower limit of 15° is not reached, it is difficult to observe images in the image pickup range. As the upper limit of 30° is exceeded, the whole size of the electronic view finder can hardly be reduced. [0138] More preferably, this angle of field should be in the range of 20° to 26°. [0139] According to the 32nd aspect of the invention, there is provided an image pickup system comprising an image pickup device, an image display device for displaying an image, a controller for converting image formation obtained from said image pickup device into a signal that enables said image information to be formed on said image display device, and a viewing optical system for guiding an image displayed on said display device to a viewer's eye, characterized in that: [0140] said image display device is a reflection type image display device for displaying an image by illumination from a display screen side thereof and comprises an illumination member for illuminating the display screen of said reflection type image display device, and [0141] said viewing optical system comprises a plurality of lens elements and further includes at least one aspheric surface. [0142] What is achieved by the 32nd image pickup system is briefly explained. [0143] For observing sharp images, it is more preferable to use a reflection type image display device as the image display device with the viewing optical system comprising a plurality of lens elements and further including at least one aspheric surface, because it is possible to make use of the high aperture efficiency of that reflection type image display device. [0144] According to the 33rd aspect of the invention, there is provided an image pickup system comprising an image pickup device, an image display device for displaying an image, a controller for converting image formation obtained from said image pickup device into a signal that enables said image information to be formed on said image display device, and a viewing optical system for guiding an image displayed on said display device to a viewer's eye, characterized in that: [0145] said viewing optical system comprises a plurality of lens components in which all surfaces thereof, in contact with air, are convex on an air side, and an angle of field, 2ω, in a diagonal direction of an image being observed through said viewing optical system is at least 22.01°. [0146] According to the 34th aspect of the invention, the 33rd image pickup system is further characterized in that the angle of field, 2ω, in the diagonal direction of the image being observed through said viewing optical system is at least 23.01°. [0147] What is achieved by the 33rd and 34th image pickup systems is now described. [0148] For the viewing optical system it is required to have positive refracting power. Preferably in this case, however, the positive refracting power should be dispersed. By using a plurality of lens components in which all the surfaces thereof, in contact with air, have positive powers, it is thus easy to make the angle of field wide. If the angle of field, 2ω, in the diagonal direction of the image under observation is at least 22.01°, it is then easy to see the image large. In particular, the angle of field of 22.01° makes observation easier. [0149] According to the 35th aspect of the invention, the 1st, 16th, 24th, 26th, 32nd or 33rd image pickup system is further characterized in that a diagonal length of the display screen of said image display device is in the range of 2.5 mm to 8 mm. [0150] No account is given of what is achieved by the 35th image pickup system because the same as set forth in conjunction with the 29th image pickup system is achieved. [0151] According to the 36th aspect of the invention, the 1st, 16th, 24th or 26th image pickup system is further characterized in that the angle of field in the diagonal length of the image being observed through said viewing optical system is in the range of 15° to 30°. [0152] No account is given of what is achieved by the 36th image pickup system because the same as mentioned in conjunction with the 31st image pickup system is achieved. [0153] According to the 37th aspect of the invention, the 1st, 16th, 24th, 26th, 29th or 33rd image pickup system is further characterized in that said image display device is a reflection type image display device for displaying an image by illumination from a display screen side thereof, and comprises an illumination member for illuminating the display screen of said reflection type image display device. [0154] No account is given of what is achieved by the 37th image pickup system because the same as mentioned in conjunction with the 32nd image pickup system is achieved. [0155] According to the 38th aspect of the invention, the 16th, 29th or 32nd image pickup system is further characterized in that said viewing optical system comprises a plurality of lens components in which all surfaces thereof, in contact with air, are convex on an air side. [0156] No account is given of what is achieved by the 38th image pickup system because the same as mentioned in conjunction with the 33rd image pickup system is achieved. [0157] According to the 39th aspect of the invention, the 1st, 16th, 24th, 26th, 29th, 32nd or 33rd image pickup system is further characterized by further comprising a phototaking optical system for guiding a light beam to said image pickup device. [0158] What is achieved by the 39th image pickup system is now explained. [0159] While the present invention has been described on the premise that the phototaking optical system is used, it is understood that the image pickup system proper may be provided with a mount at which replaceable phototaking optical systems are arbitrarily mounted. Such an image pickup system free from any phototaking optical system, too, is included in the image pickup system of the invention. [0160] It is also understood that if an image pickup optical system for guiding a light beam to the image pickup device is used as in the 39th image pickup system, it is then possible to observe a subject's image depending on the properties (angle of view, depth of focus, etc.) of the image pickup optical system. [0161] According to the 40th aspect of the invention, there is provided an image pickup system comprising an image pickup device, an image display device for displaying an image, a controller for converting image formation obtained from said image pickup device into a signal that enables said image information to be formed on said image display device, and a viewing optical system for guiding an image displayed on said display device to a viewer's eye, characterized in that: [0162] said viewing optical system consists of two single-lens elements or, in order from said display device side, a single-lens element in a negative meniscus form convex on said display device side and a positive single-lens element in a double-convex form, and surfaces located from a display screen to a viewer's eyeball are all composed only of refracting surfaces. [0163] What is achieved by the 40th image pickup system is now explained. [0164] With the lens arrangement where the negative single-lens element and the double-convex positive single-lens element are located in order from the display screen side, it is possible to secure a wide field. [0165] Preferably in this case, the negative lens element should be in a meniscus form convex on the display screen side, because the surface of positive power, the surface of negative power and the surface of positive power are arranged in order from the display screen side so that aberrations can be well corrected with a reduced number of lenses. [0166] Furthermore, much more simplified construction is achievable because of no reflection of an optical path from the display screen. [0167] According to the 41st aspect of the invention, the 40th image pickup system is further characterized by satisfying the following condition (3): 1.4 <f e /a <2.4  (3) Here the small letter a is the distance from the display screen of the image pickup device to the surface, nearest to the image display device side, of the viewing optical system, and f e is the focal length of the viewing optical system. [0168] No account is given of what is achieved by the 41st image pickup system because the same as mentioned in conjunction with the 15th image pickup system is achieved. [0169] According to the present invention, a plurality of the aforesaid aspects may be used in suitable combinations while the effect of each aspect is kept intact. [0170] Even though only the upper or lower limit to each condition is satisfied, the effect corresponding to that limit may be achievable. [0171] It is also understood that the values referred to in the following examples may be used as the upper or lower limit values. [0172] Still other objects and advantages of the invention will in part be obvious and will in part be apparent from the specification. [0173] The invention accordingly comprises the features of construction, combinations of elements, and arrangement of parts which will be exemplified in the construction hereinafter set forth, and the scope of the invention will be indicated in the claims. BRIEF DESCRIPTION OF THE DRAWINGS [0174] FIG. 1 is illustrative in schematic of the construction of a digital camera that is one embodiment of the image pickup system according to the invention. [0175] FIG. 2 is illustrative of the construction of a sliver-salt camera to which the image pickup system of the invention is applied. [0176] FIG. 3 is illustrative of the construction of a typical electronic view finder according to the invention. [0177] FIGS. 4 ( a ) through 4 ( d ) are sectional views inclusive of the optical axes of the viewing optical systems in Examples 1 to 4 of the invention. [0178] FIGS. 5 ( a ) through 5 ( c ) are sectional views inclusive of the optical axes of the viewing optical systems in Examples 5 to 7 of the invention. [0179] FIG. 6 is an aberration diagram for the viewing optical system of Example 1. [0180] FIG. 7 is an aberration diagram for the viewing optical system of Example 2. [0181] FIG. 8 is an aberration diagram for the viewing optical system of Example 3. [0182] FIG. 9 is an aberration diagram for the viewing optical system of Example 4. [0183] FIG. 10 is an aberration diagram for the viewing optical system of Example 5. [0184] FIG. 11 is an aberration diagram for the viewing optical system of Example 6. [0185] FIG. 12 is an aberration diagram for the viewing optical system of Example 7. DESCRIPTION OF THE PREFERRED EMBODIMENTS [0186] Some embodiments of the image pickup system according to the invention are now explained. [0187] FIG. 1 is illustrative of the construction of a digital camera that is one embodiment of the image pickup system according to the invention. [0188] Referring to FIG. 1 , reference numeral 10 indicates an image pickup system or a digital camera comprising an image pickup optical system 1 , a filter 2 , an image pickup device 3 , a controller 4 , a built-in memory 5 , an electronic view finder 6 , and an interface 7 . [0189] In the aforesaid image pickup system, light emanating from an object point is focused through the image pickup system 1 comprising optical elements (such as lenses) on the light-sensing surface of the image pickup device 3 such as a CCD to form an object image thereon. The image pickup device 3 is an array of regularly arranged photoelectric converters, and between the image pickup system 1 and the image pickup device 3 there is located a filter 2 having a low-pass effect on prevention of a moiré phenomenon due to such an array. In some cases, an infrared cut filter for cutting off infrared light may be located. [0190] A light beam incident on the image pickup device 3 is converted by the photoelectric converters to electric signals which are then inputted into the controller 4 , where they are subjected to image processing such as gamma correction and image compression and then sent to a personal computer 9 or the like via the built-in memory 5 and interface 7 . [0191] The resultant signals are then transmitted to a reflection type image display device (not shown in FIG. 1 ), from which they are fed to the electronic view finder 6 comprising an illumination system, a reflection type image display device, a viewing optical system or the like, so that the image to be picked up or the picked up image can be observed by an observer. Image data may be sent from the built-in memory 5 to an auxiliary memory 8 , while the same image data may be sent from the interface 7 to the personal computer 9 . [0192] FIG. 2 is illustrative of the construction of a silver-salt camera to which the image pickup system according to the invention is applied. As shown in FIG. 2 , a silver-salt camera 20 comprising the image pickup system of the invention is provided with an image pickup optical system 11 , a film 12 , an objective lens 13 , an image pickup device 14 such as a CCD, a first controller 15 and another or a second controller 16 as well as, as in the case of the FIG. 1 digital camera, a built-in memory 5 and an electronic view finder 6 . [0193] In the silver-salt camera 20 shown in FIG. 2 , a light beam from an object point is focused through the image pickup optical system 11 on the film 12 to form an object image thereon. A light beam from the object point is also focused through the objective lens 13 separate from the image pickup optical system 11 on the image pickup device 14 such as a CCD to form an object image thereon. The light beam incident on the image pickup device 14 is converted by photoelectric converters forming the image pickup device 14 to electric signals, which are then inputted into the first controller 15 , where they are subjected to image processing such as gamma correction and image compression and then sent to a reflection type image display device and fed to the electronic view finder 6 constructed of an illumination system, a reflection type image display device, a viewing optical system, etc., so that the image to be picked up can be observed by an observer. [0194] On the other hand, if information, etc. stored by the controller 15 in the built-in memory 5 are used, it is then possible for the user (observer) to view the picked-up image. [0195] The second controller 16 is provided to control the image pickup optical system 11 . On the basis of signals from the second controller 16 , the first controller 15 may recognize information on the zooming, focusing, etc. of the image pickup optical system 11 , so that adjustments are made depending on the image pickup angle of view of the image to be displayed on the reflection type image display device. Alternatively, the second controller 16 may recognize information on the focusing, etc. of the image pickup optical system 11 , so that the range of the image displayed on the reflection type display device is corrected (for parallax). Still alternatively, signals may be sent from the first controller 15 to the built-in memory 5 or an interface (not shown), thereby producing output on a personal computer or the like. [0196] Further, the objective lens 13 may be dispensed with. For instance, a light beam from the image pickup optical system 11 may be split into two or more beams, one of which is used for finder purposes. This finder light beam is used to form an image on the image pickup device 14 such as a CCD for viewing purposes. [0197] Next, the electronic view finder used herein is explained. [0198] FIG. 3 is illustrative of the construction of a typical electronic view finder used herein. Reference numerals 21 R, 21 G and 21 B represent a red light source, a green light source and a blue light source, respectively. For instance, light-emitting diodes are used. Reference numeral 22 stands for an illumination optical system, 23 a viewing optical system, 24 the optical axis of the viewing optical system 23 , 25 a viewer's eye, 26 a reflection type image display device, and 27 a plane-parallel plate with a polarizing half-silvered mirror 28 mounted thereon. [0199] In the thus constructed finder, illumination light from the light sources 21 R, 21 G and 21 B is reflected by the illumination optical system 22 comprising a reflecting mirror in one direction (upwardly in FIG. 3 ). The optical axis 24 of the viewing optical system 23 is designed to intersect vertically the substantial center of the image display device 26 . [0200] Leaving the light sources 21 R, 21 G and 21 B and reflected by the illumination optical system 22 constructed of a reflecting mirror in one direction, illumination light propagates with its center intersecting almost vertically the optical axis 24 of the viewing optical system 23 , and is then reflected at the half-silvered mirror 28 toward the reflection type image display device 26 . [0201] The reflection type image display device 26 used is a reflection type twisted nematic liquid crystal display device with its twist angle set at 45°. [0202] An image displayed on this reflection type display device 26 is viewed by an observer via the viewing optical system 23 through the plane-parallel plate 27 with the polarizing half-silvered mirror 28 mounted thereon. [0203] In the electronic view finder of such construction, when the illumination light emanating from the light sources 21 R, 21 B and 21 B is in a randomly polarized state, it is linearly polarized by the polarizing half-silvered mirror 28 in a certain direction for illuminating the liquid crystal display device 26 . For instance, when the polarizing half-silvered mirror 28 is designed in such a way as to reflect S waves and transmit P waves, the illumination light reflected at the half-silvered mirror 28 is defined by S waves. Reflected at the half-silvered mirror 28 to illuminate the liquid crystal display device 26 that is an image display device, the illumination light passes through voltage-applied pixels and a liquid crystal layer, at the bottom of which it is reflected, leaving with the polarizing direction turned through 90°. Thus, the illumination light, which has been entered as S waves into the image pickup display device 26 and modulated thereat, leaves in the form of P waves. Upon re-incidence on the plane plate 27 , nearly all this P-wave light transmits through the polarizing half-silvered mirror 28 , arriving at a viewer's eye 25 via the viewing optical system 23 . [0204] The light sources 21 R, 21 G and 21 B are put on in order, so that red, green and blue light rays are successively guided to the liquid crystal display device 26 . In turn, the liquid crystal display device 26 displays successively images corresponding to the thus guided light rays, so that color images are formed. [0205] As mentioned above, the electronic view finder used herein can be a compact, light-weight finder that is simplified in construction, and makes effective use of light, because of no substantial losses in the quantity of light emanating from the light sources 21 R, 21 G and 21 B. The action of the viewing optical system 23 enables the observer to perceive images on the image display device 26 as virtual images on an enlarged scale. Preferably in this case, the electronic view finder should be designed such that an illumination optical path where light beams leaving the light sources 21 R, 21 G and 21 B enter the image display device 26 upon reflection at the polarizing half-silvered mirror 28 and a viewing optical path where light beams reflected at the image display device 26 are guided to the viewer's eye upon transmission through the polarizing half-silvered mirror 28 form a reciprocating optical path between the polarizing half-silvered mirror 28 and the image display device 26 . With this arrangement, the optical path through the viewing optical system can be used as a combined forward and backward optical path, so that wasted optical elements (transmitting surfaces or reflecting surfaces) and space can be eliminated unlike an optical system having separate two optical paths, thereby making the image pickup system compact. This arrangement is also helpful for prevention of flare light. [0206] In the finder shown in FIG. 3 , it is noted that a curved surface such as a rotationally symmetric paraboloid may be used instead of the half-silvered mirror 28 . It is also noted that the illumination optical system 22 may be located at an optical path passing through the half-silvered mirror 28 and the viewing optical system 23 may be positioned at an optical path for reflecting the half-silvered mirror 26 . In the case, the distance a from the display screen of the image display device 26 to the surface of the viewing optical system 23 located nearest to the image display device 26 side is understood to mean the length of that optical path. [0207] The viewing optical system 23 in the electronic view finder shown in FIG. 3 may be constructed as in the following examples. [0208] In the following Examples 1 to 5, the display screen is in a rectangular form having a length of 3.84 mm in the horizontal direction and a length of 2.88 mm in the vertical (short-side) direction with a diagonal length of 4.8 mm. In the following Example 6, the display screen is in a rectangular form having a length of 8.96 mm in the horizontal direction and a length of 6.66 mm in the vertical (short-side) direction with a diagonal length of 11.164 mm. [0209] FIGS. 4 ( a ) through 4 ( d ) are sectional views including the optical axes of the viewing optical systems according to Examples 1 to 4, and FIGS. 5 ( a ) through 5 ( c ) are sectional views including the optical axes of the viewing optical systems according to Examples 5 to 7. Numerical data on these examples will be enumerated later. In each example, “LCD” represents a liquid crystal display device forming part of the image display device, “EP” an eye point”, and “L” the diagonal length of the image display device. [0210] As shown in FIG. 4 ( a ), the viewing optical system of Example 1 is composed of, in order from the image display device side, a double-convex positive lens and a doublet consisting of a double-convex positive lens and a negative meniscus lens concave on its object side, while the surface nearest to the eye point side is formed of an aspheric surface. [0211] The values for conditions (1) to (3) in this example and the angle of field, 2ω, in the diagonal direction of an image-under observation are as follows: [0212] a=6.59 mm [0213] b=16.06 mm [0214] c=2.88 mm [0215] f e =12.77 mm [0216] b/a=2.435 [0217] a/c=2.289 [0218] f e /a=1.937 [0219] 2ω=22.01° [0220] As shown in FIG. 4 ( b ), the viewing optical system of Example 2 is composed of, in order from the display device side, a doublet consisting of a double-convex positive lens and a negative meniscus lens concave on its object side and a double-convex positive lens, while the object side-surface of the double-convex positive lens located on an eye point side is formed of an aspheric surface. [0221] The values for conditions (1) to (3) in this example and the angle of field, 2ω, in the diagonal direction of an image under observation are as follows: [0222] a=7.00 mm [0223] b=13.12 mm [0224] c=2.88 mm [0225] f e =11.97 mm [0226] b/a=1.876 [0227] a/c=2.430 [0228] f e /a=1.710 [0229] 2ω=23.01° [0230] As shown in FIG. 4 ( c ), the viewing optical system of Example 3 is composed of, in order from a display device side, a double-convex positive lens and a doublet consisting of a double-convex positive lens and a negative meniscus lens concave on its object side, while the surface, on an eye point side, of the double-convex positive lens on the object side is formed of an aspheric surface. [0231] The values for conditions (1) to (3) in this example and the angle of field, 2ω, in the diagonal direction of an image under observation are as follows: [0232] a=6.52 mm [0233] b=15.13 mm [0234] c=2.88 mm [0235] f e =12.09 mm [0236] b/a=2.319 [0237] a/c=2.265 [0238] f e /a=1.853 [0239] 2ω=23.03° [0240] As shown in FIG. 4 ( d ), the viewing optical system of Example 4 is composed of, in order from a display device side, a negative meniscus lens convex o its object side and a double-convex positive lens while the object-side surface of the double-convex positive lens is formed of an aspheric surface. [0241] The values for conditions (1) to (3) in this example and the angle of field, 2ω, in the diagonal direction of an image under observation are as follows: [0242] a=12.28 mm [0243] b=8.03 mm [0244] c=2.88 mm [0245] f e =18.24 mm [0246] b/a=0.654 [0247] a/c=4.266 [0248] f e /a=1.485 [0249] 2ω=15.05° [0250] As shown in FIG. 5 ( a ), the viewing optical system of Example 5 is composed of, in order from a display device side, a double-concave negative lens and a double-convex positive lens, while the eye point-side surface of the double-convex positive lens is formed of an aspheric surface. [0251] The values for conditions (1) to (3) in this example and the angle of field, 2ω, in the diagonal direction of an image under observation are as follows: [0252] a=10.91 mm [0253] b=8.49 mm [0254] c=2.88 mm [0255] f e =18.24 mm [0256] b/a=0.778 [0257] a/c=3.789 [0258] f e /a=1.671 [0259] 2ω=15.45° [0260] As shown in FIG. 5 ( b ), the viewing optical system of Example 6 is made up of, in order from a display device side, a double-concave negative lens and a double-convex positive lens while the object-side surface of the double-convex positive lens is formed of an aspheric surface. [0261] The values for conditions (1) to (3) in this example and the angle of field, 2ω, in the diagonal direction of an image under observation are as follows: [0262] a=14.64 mm [0263] b=9.16 mm [0264] c=6.66 mm [0265] f e =21.21 mm [0266] b/a=0.626 [0267] a/c=2.198 [0268] f e /a=1.448 [0269] 2ω=30.04° [0270] As shown in FIG. 5 ( c ), the viewing optical system of Example 7 is made up of, in order from a display device side, a negative meniscus lens convex on the display device side and a double-convex positive lens while the object-side surface of the double-convex positive lens is formed of an aspheric surface. In this example, there is used a transmission type liquid crystal display device wherein light sources are located on the back side of a display screen so that an image is formed by light transmitting through the transmission type liquid crystal display device. [0271] The values for conditions (1) to (3) in this example and the angle of field, 2ω, in the diagonal direction of an image under observation are as follows: [0272] a=15.04 mm [0273] b=10.38 mm [0274] c=6.66 mm [0275] f e =21.27 mm [0276] b/a=0.69 [0277] a/c=2.26 [0278] f e /a=1.41 [0279] 2ω=30.02° [0280] In what follows, numerical data on each example will be given. It is noted that r 1 , r 2 , * * * represent the radius of curvature of each lens surface, d 1 , d 2 , * * * represent the spacing between lens surfaces, n d1 , n d2 , * * * represent the d-line refractive index of each lens, and ν d1 , ν d2 , * * * represent the Abbe number of each lens. It is also noted that r 0 stands for the radius of curvature of the display screen of “LCD”, d 0 indicates the spacing between the display screen of “LCD” and the first lens surface, r 6 in Examples 1-3 and r 5 in Examples 4-6 each show the radius of curvature of the “EP” surface, and d 5 in Examples 1-3 and d 4 in Examples 4-6 each represent an eye relief. Length is given in mm. Here let x stand for an optical path provided that the direction of propagation of light is positive and y indicate a direction perpendicular to the optical axis. Aspheric surface shape is given by x =( y 2 /r )/[1+{1−( K +1)( y/r ) 2 }/ 1/2 ]+A 4 y 4 +A 6 y 6 +A 8 y 8 Here r is a paraxial radius of curvature, K is a conical coefficient, and A 4 , A 6 and A 8 are the 4th, 6th and 8th aspheric coefficients, respectively. EXAMPLE 1 [0281] r 0 = ∞ (LCD) d 0 = 6.59 r 1 = 52.055 d 1 = 6.86 n d1 = 1.58913 ν d1 = 61.14 r 2 = −11.570 d 2 = 1.09 r 3 = 54.042 d 3 = 6.06 n d2 = 1.56384 ν d2 = 60.67 r 4 = −9.258 d 4 = 2.05 n d3 = 1.80518 ν d3 = 25.42 r 5 = −17.680 (Aspheric) d 5 = 17.00 r 6 = ∞ (EP) Aspherical Coefficients 5th surface K = 0.000 A 4 = 1.57513 × 10 −5 A 6 = 2.15451 × 10 −7 A 8 = −4.32763 × 10 −9 EXAMPLE 2 [0282] r 0 = ∞ (LCD) d 0 = 7.00 r 1 = 10.449 d 1 = 7.54 n d1 = 1.56384 ν d1 = 60.67 r 2 = −14.467 d 2 = 1.64 n d2 = 1.80518 ν d2 = 25.42 r 3 = −114.013 d 3 = 0.50 r 4 = 20.456 (Aspheric) d 4 = 3.45 n d3 = 1.58913 ν d3 = 61.14 r 5 = −18.079 d 5 = 17.00 r 6 = ∞ (EP) Aspherical Coefficients 4th surface K = 0.000 A 4 = −3.29162 × 10 −4 A 6 = 1.70351 × 10 −6 A 8 = −7.06260 × 10 −8 EXAMPLE 3 [0283] r 0 = ∞ (LCD) d 0 = 6.52 r 1 = 52.055 d 1 = 8.25 n d1 = 1.58913 ν d1 = 61.14 r 2 = −10.708 (Aspheric) d 2 = 0.30 r 3 = 34.600 d 3 = 5.78 n d2 = 1.56384 ν d2 = 60.67 r 4 = −9.258 d 4 = 0.80 n d3 = 1.80518 ν d3 = 25.42 r 5 = −23.115 d 5 = 17.00 r 6 = ∞ (EP) Aspherical Coefficients 2nd surface K = 0.000 A 4 = 4.79644 × 10 −5 A 6 = −6.80364 × 10 −7 A 8 = 5.86617 × 10 −9 EXAMPLE 4 [0284] r 0 = ∞ (LCD) d 0 = 12.28 r 1 = 50.414 d 1 = 1.06 n d1 = 1.58423 ν d1 = 30.49 r 2 = 9.124 d 2 = 0.55 r 3 = 9.908 (Aspheric) d 3 = 6.42 n d2 = 1.49236 ν d2 = 57.86 r 4 = −9.014 d 4 = 17.00 r 5 = ∞ (EP) Aspherical Coefficients 3rd surface K = 0.000 A 4 = −4.23266 × 10 −4 A 6 = 1.26605 × 10 −5 A 8 = −1.87739 × 10 −7 EXAMPLE 5 [0285] r 0 = ∞ (LCD) d 0 = 10.91 r 1 = −26.234 d 1 = 1.06 n d1 = 1.58423 ν d1 = 30.49 r 2 = 24.828 d 2 = 1.51 r 3 = 13.612 d 3 = 5.92 n d2 = 1.49236 ν d2 = 57.86 r 4 = −8.868 (Aspheric) d 4 = 17.00 r 5 = ∞ (EP) Aspherical Coefficients 4th surface K = 0.000 A 4 = 2.46412 × 10 −4 A 6 = 2.50349 × 10 −6 A 8 = 1.52473 × 10 −8 EXAMPLE 6 [0286] r 0 = ∞ (LCD) d 0 = 14.64 r 1 = −37.022 d 1 = 1.02 n d1 = 1.58423 ν d1 = 30.49 r 2 = 52.882 d 2 = 1.32 r 3 = 15.833 (Aspheric) d 3 = 6.82 n d2 = 1.52542 ν d2 = 55.78 r 4 = −13.482 d 4 = 17.00 r 5 = ∞ (EP) Aspherical Coefficients 3rd surface K = 0.000 A 4 = −2.24211 × 10 −4 A 6 = 6.92370 × 10 −7 A 8 = −1.96757 × 10 −9 EXAMPLE 7 [0287] r 0 = ∞ (LCD) d 0 = 15.04 r 1 = 68.309 d 1 = 1.77 n d1 = 1.58423 ν d1 = 30.49 r 2 = 17.414 d 2 = 0.71 r 3 = 13.379 (Aspheric) d 3 = 7.90 n d2 = 1.52542 ν d2 = 55.78 r 4 = −15.234 d 4 = 17.00 r 5 = ∞ (EP) Aspherical Coefficients 3rd surface K = 0.000 A 4 = −1.72329 × 10 −4 A 6 = 7.59604 × 10 −7 A 8 = −5.05665 × 10 −9 [0288] FIGS. 6 to 12 are aberration diagrams for Examples 1 to 7, in which “SA”, “AS” and “CC” represent spherical aberrations, astigmatism and chromatic aberration of magnification, respectively. [0289] As can be appreciated from the foregoing, the present invention can provide such image pickup systems as summarized below: [0290] an image pickup system having an electronic view finder suitable for achieving compactness; [0291] an image pickup system that enables an observer to have an easy grasp of the image pickup range; [0292] an image pickup system that gets hold of a sufficient angle of field and satisfactory optical performance even when using an image display device provided with a display screen having a short diagonal length; [0293] an image pickup system having an electronic view finder with well-corrected chromatic aberration of magnification; [0294] an image pickup system provided with an electronic view finder wherein dust, etc. deposited on a viewing optical system are unnoticeable; and [0295] an image pickup system provided with an electronic view finder that enables appropriate optical elements to be located even when a reflection type image display device is used as an image display device.

The invention relates to an image pickup system comprising an electronic view finder suitable for achieving compactness and having a sufficient viewing angle of field and satisfactory optical performance. The image pickup system comprises an image pickup device, an image display device for displaying an image, a controller for converting image formation obtained from the image pickup device into a signal that enables the image information to be formed on the image display device, and a viewing optical system for guiding an image displayed on the display device to a viewer's eye. The viewing optical system comprises at least three lenses.

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a radar system for use on cars and radar modules thereof, and in particular to a small-sized and low production cost radar module and radar system. 2. Description of the Related Art A radar system loaded on cars, such as passenger car, is utilized in combination with an alarm device or display device for avoiding collision. In such a car-loaded radar system, detectability for a short distance on the order of tens of centimeters is required since a rear-end impact in a short distance between cars during traffic congestion or near collisions during putting a car into a garage is also a target to be warned, and hereby the shape of FM radar signal is more suitable than that of pulse radar. Also in miniaturizing a module, using a millimeter electric wave having a high frequency is preferable. Such a millimeter wave FM radar system is disclosed in the specification of U.S. Pat. Nos. 5,181,037 and 5,229,774 related to the prior application of the present applicant. Generally, in an FM radar system, the frequency of a beat signal is arranged to rise in proportion to the distance to an object that generated a reflected wave. Accordingly, with shorter distance to the object, the frequency of a beat signal lowers and becomes undetectable under disturbance of 1/f noise which is generated in a mixer. In an FM radar system according to the prior patents mentioned above, to reduce the effect of 1/f noise by raising the frequency of a beat signal, a heterodyne method for modifying the frequency of a local signal is employed or a delay line is inserted. However, a heterodyne method requires a local oscillator used for frequency conversion and accordingly becomes expensive, whereas a method for inserting a delay circuit has a size problem in that an inserted delay line requires a module to be larger in size. Furthermore, an FM radar system according to the prior patents mentioned above is arranged to switch a transmitter step multiplier, a circulator, antennas used in common for transmission and receiving, a mixer and a receiver step multiplier constituting each FM radar module by a synchronous operation between a transmitter side switch and a receiver side switch. Thus, as many transmitter-receiver sections as antennas become necessary and the number of parts increase, so that there arise problems that the whole FM module does not only become large in size but production cost also increases considerably. SUMMARY OF THE INVENTION It is the object of the present invention to provide a small-sized and low-production-cost radar module comprising a few parts and a radar system using this radar module by implementing an arrangement in which a transmitter-receiver section is used in common with a plurality of antennas. In a radar module according to the present invention, a planar array antenna used in common for transmission and receiving and a transmitter-receiver section for supplying a radiative signal to this array antenna and receiving the reflected signal are layered via an intermediate layer on which a delay section made of a delay line is formed. According to a preferred embodiment of the present invention, said planar array antenna comprises a plurality of antenna portions used in common for transmission and receiving and a selective connection section for selectively connecting each of these antenna portions via said delay line to said transmitter-receiver section. A delay line implemented with a microstrip line or the like is provided for improving a detection function at near distance by seemingly moving an obstacle to be detected to the front of a car and raising the frequency of a beat signal. This delay line needs to be typically as long as tens of centimeters. By employing a fold back structure, such as a meander line, and a spiral structure, shortening the length of a delay line is performed but is limited in itself. According to the present invention, the size is greatly reduced by placing a delay line between a planar array antenna and a transmitter-receiver section in built layers rather than by placing a delay line in the same plane as with a planar array antenna and a transmitter-receiver section. According to a preferred embodiment of the present invention, a low-loss resin wave guide newly developed is employed as a delay line. According to a more preferred embodiment of the present invention, a plurality of antenna portions used in common for transmission and receiving are selectively connected to a transmitter-receiver section under control of a selective connection section. Accordingly, one series of transmitter-receiver section including an amplifier, circulator and mixer, is enough for this and thus the number of parts and the space is greatly reduced. BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING FIG. 1 is a sectional view showing the configuration of an FM radar module according to one embodiment of the present invention; FIG. 2 is a plan view showing the constitution of each layer (A: planar array antenna PA taken along a line 2A--2A of FIG. 1; B: delay section DL taken along a line 2B--2B of FIG. 1; and C: transmitter-receiver section TR taken along a line 2C--2C of FIG. 1) of the FM radar module shown in FIG. 1; FIG. 3 is a block diagram showing one example of a typical FM radar system including the FM radar module shown in FIGS. 1 and 2; FIG. 4 is a plan view showing the planar array antenna PA in the top layer shown in FIGS. 1 and 2 (A); FIG. 5 is a sectional view showing one example of a resin wave guide d comprising the delay section DL in the intermediate layer shown in FIGS. 1 and 2 (B); FIG. 6 is a drawing showing one example of beam patterns B1 to B4 of electric waves radiated from each of the antenna portions A1 to A4 shown in FIG. 3; and FIG. 7 is a drawing showing the disposition and one example of beam pattern of four radar modules LM1 to LM4 included in the car-loaded FM radar system shown in FIG. 3. DETAILED DESCRIPTION Referring to the accompanying drawings, the embodiments of the present invention will be described. FIG. 1 is a sectional view showing the configuration of an FM radar module according to one embodiment of the present invention. This FM radar module is so constructed that a planar array antenna PA commonly used for transmission and receiving and a transmitter-receiver section TR for supplying an FM signal to be radiated to this planar array antenna and receiving the received signal are vertically layered via a signal delay section DL in the intermediate layer on which a delay line d is formed. An input signal to or output signal from the monolithic microwave integrated circuit (MMIC) is input or output through a terminal T1. An input signal for scanning a beam is input to a terminal T2, by which the planar array antenna PA is controlled. The planar array antenna PA has a plurality of patches P11 to P44 provided on the surface of a dielectric board DB. On the rear face of the dielectric board DB, a grounding metal layer GP is formed. The planar array antenna PA is covered and protected with a radome R from the external environment. A planar array antenna PA, the top layer of a layered block, a delay section DL, the intermediate layer, and a transmitter-receiver section TR, the bottom layer are so constructed as shown in the respective plan views of FIGS. 2 (A), (B), and (C). Between the planar array antenna PA of the top layer and one terminal of a delay line d forming the signal delay section DL of the intermediate layer a high frequency connection is provided via a pin P1. Between the other terminal of the delay line d and the transmitter-receiver section TR, the bottom layer, a high frequency connection is achieved via a pin P2. The FM radar module according to the present embodiment shown in FIGS. 1 and 2 corresponds, for example to one of four FM radar modules LM1 to LM4 constituting the car-loaded FM radar system shown in the block diagram of FIG. 3. The car-loaded FM radar system shown in FIG. 3 comprises four FM radar modules LM1 to LM4 and a process block PS for controlling an action of each FM radar module, processing a signal including information relative to an obstacle, and issuing an alarm. As represented by FM radar module LM1, each of FM radar modules LM1 to LM4 comprises a transmitter-receiver section TR in the bottom layer including an FM signal generator M1, a signal delay section DL, in the intermediate layer, including a delay line d, and a multibeam planar antenna section PA, in the top layer, including four antenna portions A1 to A4. As shown in the enlarged plan view of FIG. 4, a planar array antenna PA in the top layer, includes 16 patches of rectangular shape P11-P14, P21-24, P31-34, and P41-P44 arranged on the dielectric board DB on the rear face of which a grounding metal layer GP is formed. At the center of the dielectric board DB, a power section P corresponding to the tip part of the pin P1 is formed. Supply lines S0, and S1 to S4 of microstrip type for connecting this power section P and each patch is formed on the dielectric board DB. 16 patches P11-14, p21-24, p31-34, and P41-44 form four antenna portions A1, A2, A3, and A4 for radiating beams of different tilt angles set in according with a difference in the length of supply lines to them. The right lower antenna portion A1 comprises left two patches P11, P12 of the same supply line length measured from the power section P and right two patches P13, P14 of a supply line length longer by L1 than these, whereas the right upper antenna portion A2 comprises left two patches P21, P22 of the same supply line length measured from the power section P and right two patches P23, P24 of a supply line length longer by L2 than these. Similarly, the left upper antenna portion A3 comprises right two patches P31, P32 of the same supply line length measured from the power section P and left upper two patches P33, P34 of a supply line length longer by L3 than these, whereas the left lower antenna portion A4 comprises right two patches P41, P42 of the same supply line length measured from the power section P and left two patches P43, P44 of a supply line length longer by L4 than these. The supply line lengths L1-L4 shift the phase of supply signal between the left patches (P11, P12 etc.) and right patches (P13, P14 etc.) and tilt up transmit-receive beam in accordance with the phase difference. Power supply from the power section P to the antenna portion A1 is provided through supply lines S0 and S1 of microstrip type, while power supply from the power section P to the antenna portion A2 is provided through supply lines S0 and S2. Power supply from the power section P to the antenna portion A3 and to the antenna section A4 is provided through supply lines S0 and S3 and through supply lines S0 and S4, respectively. Between the supply line S0 and the individual supply lines S1 to S4, respective PIN diodes D1, D2, D3 and D4 excellent in high frequency characteristics are provided. A bias circuit for each PIN diode is formed including bias input terminals V0 and V1 to V4, and low-pass filters F0 and F1 to F4 on the dielectric board DB. That is, a positive voltage is always kept to be applied to a common bias input terminal V0, while either a higher positive voltage than that applied to the terminal V0 or the ground (zero) voltage is selectively applied to each of the bias input terminals V1 to V4. This selective voltage is supplied from a timing control circuit P3 in the processing section PS of FIG. 3 through a terminal T2 of FIG. 1. When the ground voltage is applied to any of bias input terminals V1 to V4, the corresponding one of PIN diode D1 to D4 becomes conductive so that the supply line S0 and the corresponding one of supply lines S1 to S4 is electrically connected and thus a high frequency power is supplied from the power section P to the corresponding one of antenna portions A1 to A4. A delay line d comprising a signal delay section DL in the intermediate layer comprises a resin wave guide of spiral shape. This resin wave guide was newly made by the inventors for an FM radar module according to the present embodiment on an experimental basis and has a cross-sectional shape shown in FIG. 5. The resin wave guide is made of polytetrafluoroethylene (PTFE), has a rectangular cross-section, and comprises a metal foil M deposited on the surface of a rod-shaped dielectric line PTFE by plating. The aspect ratio of the cross-section of the dielectric line is approx. 1:2, and when the frequency of an FM signal to be delayed is 60 GHz, the transverse width is 3.8 mm, smaller than that of a wave guide (5.8 mm). Because of being smaller in size than a normal wave guide and elastic, this resin wave guide has advantages in that a delay line of still smaller size can be implemented with a high density winding. The passing loss in this resin wave guide is approx. 3 dB/m in a state of straight line when the frequency of a signal is 60 GHz. However, bending at a small radius of curvature increases the passing loss to on the order of 4 dB/m. This value of passing loss is greater than a value of a wave guide without dielectric loss (approx. 1.2 dB/m), but rather smaller than a value of a microstrip line (approx. 7 dB/m). The feature of a resin wave guide, formed by depositing a metal foil on the surface of a rod-like body made of polytetrafluoroethylene (PTFE) or the like, is its elasticity and accordingly its delay time can be made longer by implementing a longer dielectric line in a dense spiral shape as shown in FIGS. 1 and 2(B). Incidentally, since the passing loss increases with smaller radius of curvature, employing a helical structure in which all parts are one and the same radius of curvature enables a constitution of reduced passing loss in place of a spiral structure in which the radius of curvature decreases for the inner part. As represented by the transmitter-receiver section LM1 in FIG. 3, the transmitter-receiver section TR in the bottom layer comprises an FM signal generation circuit M1, a directional coupler M2, an amplifier M3, a circulator M4, and a mixer M6. As shown in FIG. 2 (C), this transmitter-receiver section TR is made into a monolithic microwave integrated circuit (MMIC) and housed in a package. An FM signal is provided to the package through an input/output pin P2. A timing signal or connection control instruction is input from the processing section PS in FIG. 3 through signal lines B1, B2, and DC operational power is supplied through a power supply line VB. Where the circulator M4 is relatively difficult to be made into MMIC, a hybrid microintegration construction may be employed in which the circulator M4 will be added externally of a separate member which in turn is made into MMIC, abandoning making the circulator itself into MMIC. Because of having mutually different tilt angles, the antenna sections A1 to A4 of each FM radar module radiate four beams B1 to B4 in different directions as shown in FIG. 6. Thus, if one of four beams B1, B2, B3 and B4 is radiated in sequence for a predetermined period (2-6 msec) from one of four antenna portions A1, A2, A3 and A4 by making one of four PIN diodes D1, D2, D3 and D4 conductive in the same sequence for a predetermined period (2-6 msec) and each reflected wave generated at an object is propagated along a reverse route to the power section P, then beam scanning is carried out in four different direction with these planar array antennas. Each of radar modules LM1 to LM4 is installed on four corners of a car as shown in the drawing of FIG. 7, and the processing section PS is installed at an appropriate place in the car. Referring to FIG. 3, an FM signal generator M1 in the FM radar modules LM1 to LM4 generates an FM signal whose frequency changes for a predetermined period in a sawtooth form in response to timing control signals received from the timing control circuit P3 of the processing section PS. Part of the generated FM signal is supplied through the directional coupler M2, amplifier M3, and circulator M4 to the multibeam planar array antenna PA, propagates through one of PIN diodes D1 to D4 to be turned ON/OFF (2-6 msec) in response to a control signal received from the timing control circuit P3 in the processing section PS, and radiated from the corresponding one of antenna portions A1 to A4 to the outside of a car. An FM signal radiated from an antenna portion and reflected from an object outside of the car is received by the corresponding antenna portion and supplied through the delay line d constructed using the resin wave guide and through the circulator M4 to one input terminal of the mixer M5. To the other terminal of the mixer 5, part of the FM signal generated in the FM signal generator M1 is supplied through the coupler M2. Thus, the mixer M5 outputs a beat signal whose frequency increases in accordance with the distance to the object generating the reflected wave. The respective beat signal outputted from each of FM radar modules LM1 to LM4 is supplied to the selector P5 in the processing section PS. Referring to a radar module specifying signal supplied from the timing control circuit P3, a beat signal to be supplied to the A/D conversion circuit P6 is selectively switched in a time sharing method by the selector P5. A beat signal selected by the selector P5 is converted by the A/D convertor P6 into a digital signal. The beat signal converted into a digital signal is divided into frequency spectra in a fast Fourier transformation circuit (FFT) P7. The signal processing circuit P1 comprises a CPU which does not only detect the information relative to an obstacle by referring to the frequency spectra of the beat signal and computes the position of the obstacle and the relative velocity speed of approach but also judges the possibility of collision with the obstacle and displays information relative to the existence of the obstacle, the distance to the obstacle, the possibility of collision and the like on a display P4. Incidentally, the signal processing circuit P1 can also generate a signal for controlling the accelerator and brake of the car. Heretofore, the tilt angles were set right-to-left. However, setting the tilt angles front-to-back or setting the tilt angles right-to-left and front-to-back in combination is also possible according to the present invention. Although each antenna portion is described as comprising four patches, according to the need, for example for sharpening the directional characteristic, each antenna portion can comprise a larger appropriate number of patches than four. Furthermore, an application of beam to scanning by radiating an electric wave from only one of a plurality of antenna portions is described. However, the present invention is applicable to changing the synthetic directional characteristic by radiating electric waves from any two of these. Also, a structure of implementing a delay line for an FM signal by using a resin wave guide of small passing loss is disclosed. However, when an increase in passing loss is allowable, using a delay line of microstrip type or triplet type is also possible in place of a dielectric line. Also, there is described herein an FM radar module for radiating an FM signal as an example, but the present invention is applicable also to a pulse radar module for radiating a pulse signal. As described in detail, a radar module according to the present invention presents a stereographic structure in which a planar array antenna commonly used for transmission and receiving and a transmitter-receiver section are layered via the intermediate layer in which a delay line is formed and thus has advantages in that the function of close distance detection can be implemented in a small-sized structure. Also, according to a preferred embodiment of the present invention, a planar array antenna of the type commonly used for transmission and receiving comprises a plurality of antenna portions that can be selectively connected through the above delay line to the transmitter-receiver section. Thus, a single transmitter-receiver section is used in common with a plurality of antenna portions, so that the production cost is greatly reduced with a great decrease in the number of parts and miniaturization can also be implemented.

The radar module comprises a vertical layered block of a planar array antenna, a signal delay section, and a transmitter-receiver section. The planar array antenna comprises: four antenna portions different in beam direction; and a selective connection section for selectively connecting each antenna portion with the signal delay section. Reducing the number of parts, saving the production cost and miniaturizing the apparatus is achieved by an arrangement in which a single transmitter-receiver section is in common use with a plurality of antenna portions. The signal delay section comprises a spiral dielectric line with a metal layer covering around a dielectric of rectangular section to achieve ensuring the delay time and reducing the package area.

BACKGROUND OF THE INVENTION This invention relates to thermoplastic injection molding in general, and specifically to a foam injection molding apparatus and process for foam injection molding of large parts useful in various industries. The injection molding process is one of the most prolific and universally adaptable methods used to produce molded plastic parts of many shapes, sizes, and physical properties that is available today. Unfortunately, when producing pieces over roughly 25 pounds, problems appear which reduce the efficiency of the process. Improving the overall efficiency for producing large structural pieces is one objective of this invention. Injection molding machines range from a fraction of an ounce injection capacity to very large units that can provide a shotsize over 800 ounces. The total machine process usually involves a machine, plus mold and necessary auxiliary equipment such as material granulating and loading, parts removal, etc. The typical injection molding machine consists of two basic entities: (1) the injection unit, which converts the cool solid plastic raw material into a viscous liquid by melting the plastic and then pumps it through a tube "runner system" at extremely high pressure (typically 15,000 to 20,000 psi) into the mold and (2) the clamp unit, which carries the fixed and moving halves of the mold. The clamp opens the mold to release the part previously molded then closes and builds clamp pressure against the mold during injection and solidification of the next part. The predominant injection system today is the screw-type. The present invention is drawn to methods and apparatus for improving the operating efficiency of this type of injection system. The most widely used methods of operating the clamp mechanism are: (1) toggle type, (2) straight hydraulic and (3) hydromechanical. Clamping force is required to resist the mold's tendency to open up while being injected with high pressure melted plastic. The toggle type utilizes the action of toggle linkages to multiply the force of a small hydraulic cylinder many times. This system is most used on machines from 50 to 500 tons clamp pressure. A straight hydraulic clamp mechanism utilizes a large, full-stroke hydraulic cylinder to open and close the mold and to build clamp pressure. The system is found in all sizes of machines; it is most popular, however, from 200 tons up to the largest available. The hydromechanical-type clamp mechanism utilizes small cylinders to open and close the mold and one or more large diameter, short-stroke cylinders to build full clamp pressure. This type of clamp mechanism has mainly been utilized in machines of 1,000 tons clamp pressure and over. The method of building full clamp tonnage varies between utilizing one large cylinder at the center of the machine and four smaller cylinders working on the machine's tie rods. It would be extremely advantageous if an injection molding process could be devised that could reduce the amount of clamping force required to hold the clamps closed. The large amount of clamp pressure requires a great amount of strength in the molds themselves, leading to very large molds. The larger a mold is, the more heat must be dissipated from the mold, as to be discussed below. Machines are generally sized by five parameters: (1) dimensions of the platens which hold the molds, (2) length of stroke of the platens, (3) clamp force to hold the molds closed (4) injection capacity (the maximum amount of molten plastic that can be injected ("shotsize")), and (5) plasticating rate (the rate the plastic can be melted). Once the part size and number of cavities is established, a layout of the mold can be made and physical size and stroke of the injection machine determined. The other parameters require knowledge of the material, the process, and a large amount of judgment, based mainly on tests performed on the machines. In a typical molding cycle, the plastic material is prepared and melted, accumulated and then injected or directly injected into the mold cavity, cooled, and removed from the mold. The cycle can be regarded as a large heat exchange system whereby energy is put in at the injection end; the material transferred to the mold where energy is removed (mold cooling). Unnecessary additional heat input at the injection end lengthens the cooling time required, which can be very significant for large pieces produced on such a machine; thus, proper setup is important in obtaining the most productive cycle. Further, in procedures which utilize a typical accumulator, the first melt into the accumulator is not necessarily the first out, and some degradation (and thus waste) of melt is frequent. Cooling time in general is the largest portion of the overall cycle time, except where very thin wall parts are involved. The direct time elements can be summarized as: (1) mold close and clamp build-up pressure; (2) injection of melted plastic; (3) part cooling; and (4) unclamping and opening of the mold to remove the part. Many thermoplastic and thermosetting resins can be injection molded. The process is rapid and highly reproducible parts can be achieved. However, the properties of the resin and the characteristics of the injection molding process are extremely important to achieve satisfactory products. Normally, the "melt" (molten plastic) viscosity as a function of temperature is the most important property of the polymer. For most polymer melts, the viscosity is also dependent on shear rate. This is an important property to understand since within a mold cavity, narrow cross-sections can give high shear rates with a resulting change in viscosity. Injection molded articles generally have superior mechanical properties in the direction parallel to melt flow compared to those perpendicular to melt flow (i.e., anisotropic). This is due to preferential molecular chain alignment. The extent of anisotrophy increases with decreasing melt temperature. Also, inlet melt pressure affects flow rate and usually gives larger anisotrophy in the molded material when increased. Thus, it would be advantageous to operate at higher temperatures and lower pressures. However, the high temperature leads to significantly increased cycle time, as discussed above, since the cooling time is substantially increased. The production of very large, structurally sound, but lightweight parts are the focus of many manufacturers today. Some industries, such as the automotive industry, use reaction injection molding, or RIM. RIM utilizes a complete processing system comprised of appropriate mechanical equipment and a properly compounded chemical system to achieve fast and economical production of large parts. Pumps capable of very precise volume control are known in this art. High pressure supplies sufficient energy into the materials to permit intimate mixing in impingement mixhead designs which require no solvent or air flushing between shots and can be directly attached to a mold. The machinery, which is capable of high throughputs, can fill large mold cavities, requiring more than 25 or 30 lbs. of elastomeric materials, in extremely short time periods. These efforts are indeed impressive, but the production of even larger parts is necessary to produce structures such as underground storage tanks, and other large, structurally sound products. In RIM injection molding, the processor is in fact utilizing a complex chemical reaction within the mold unit and consequently must exert a great degree of control over temperature and material flow in order to obtain the necessary reproducibility. A further disadvantage is that control of temperature affects the pumping and mixing characteristics of the ingredients as well as their reactivity. Further, RIM is not suitable for producing large size parts (greater than about 30 lbs.) having great toughness and strength. Thus, techniques other than RIM have been resorted to. When injection molding a thermoplastic material such as polypropylene, manufacturers have tried to inject gases into the polymer melt so as to control the "blow factor" of the final product. The term "blow factor," as used herein, means the percentage of void space in the final polymer product. For example, for a given volume of 1 lb. solid resin, a 25% blow factor means only 0.75 lb. of resin would fill the given volume. Manufacturers have identified polymer melt pressure, temperature and injected gas content of the polymer melt as critical factors to control the blow factor in the finished product. A slow cooling is necessary for thick-walled parts where a surface skin will harden and trap molten material at the center. If the skin is not thick enough at the time the part is removed from the mold ("ejection"), the part will shrink extensively, distort and harden with large internal voids. If cooling is too rapid, high molded-in stress and warpage of the molded piece will occur. Thus the precise cooling rate must be determined and controlled to reduce cycle time for conventional injection molding of large pieces. In very large parts, e.g., over 30 lbs., there is some cooling of the plastic as the plastic reaches the furthest extremities of the mold. This cooling affects the amount of injection force that is required to completely form the products that are injection molded since viscosity increases proportionately with cooling. Manufacturers have tried to adjust the amount of injected gas to overcome this cooling effect, by expanding gas after the melt is pumped into the mold, but their methods have been less than satisfactory. Frequently the final product wall has a thick outer skin portion which changes abruptly to an internal void region. In other words, although the final blow factor may be precisely as required in percentage of void space, the actual product will shrink extensively and distort or harden with large internal voids, as discussed above. It would be advantageous to develop an improved foam injection molding method and apparatus which overcome the disadvantages of these methods. Particularly, it would be advantageous to operate a plasticating extruder more efficiently by using it continuously in a foam injection molding process. It would also be advantageous if the molding cycle time could be reduced through efficient mold and mold gate assembly design, reducing part cooling time, which ties up valuable machine time. SUMMARY OF THE INVENTION A process and apparatus have now been discovered that allows removal of molds from the injection molding station prior to the time the product must be ejected from the mold without the loss of polymer foam from the mold, eliminating the long cooling periods required in prior methods and apparatus, and thus significantly reducing the cycle time. Further, a plasticating extruder can be operated continuously using the method and accumulator described herein, and through efficient mold gate assembly design and polymer foaming apparatus, the final blow factor of the products can be precisely controlled. The process does not require a conventional press as polymer melt is kept hot and thus at low viscosity, although conventional presses may be used if desired. The apparatus and method are suitable for processing a large variety of raw thermoplastic materials, including recyclable thermoplastics of a single type and mixtures of two or more thermoplastics. The foam injection molding process of the present invention comprises plasticating a solid polymer into a polymer melt, accumulating the polymer melt in an accumulator having a telescoping inlet and a substantially hollow piston attached to the telescoping inlet. This novel accumulator stores the melt allowing the plasticating extruder to operate continuously and, thus, more efficiently, because the extruder does not have to be shut down during periods when there is no mold in the machine. More importantly, the first polymer melt into the accumulator is the first to leave the accumulator, greatly reducing degradation and waste of polymer melt. The process further includes pumping the polymer melt into a mixing region and combining the polymer melt in the mixing region with gas in bubble form. These bubbles are of preselected size, to form a melted polymer foam. Polymer foam then proceeds through a shearing section or region, thereby reducing or maintaining the bubble size of injected gas in the polymer foam. Polymer foam is then injected into a mold, where the operator is simultaneously adjusting the mold temperature, injection pressure, and size of the injected gas bubbles in the polymer foam, thereby controlling the blow factor of the final polymer foam product to a degree not possible in previously known methods. Gases used in the process for injection into the polymer melt are generally inert to the polymer melt, although in some cases gases or gas mixtures may be used which react in some way with the polymer melt. This may be disadvantageous in some cases. Oxygen, for example, degrades most polymers by oxidation, especially polymers having double bonds, ether linkages, or tertiary carbons. If the prevention of oxidation is not critical, ordinary shop air can be used as the gas. Bottled gases, commercially available meeting known specifications, such as nitrogen, may be preferred in some applications. The gases may contain small amounts of moisture; however, if the polymer has hydrolyzable linkages such as urethanes and aliphatic ester groups, care must be taken to eliminate moisture. Preferred gases have little moisture and can be considered substantially dry. As previously stated, one advantage of the present process is in allowing the plasticating extruder to operate continuously, through action of the novel accumulator apparatus. A further advantage is realized in the fact that the molds themselves are kept at a temperature higher than would previously be recommended in such an apparatus. Previously known methods and apparatus would have the injection temperature as low as possible above the melting temperature of the polymer so that the molding cycle would be reduced by not having to cool the mold as long. In fact, the present process reduces molding cycle time, by reducing the wall thickness of molds used, reducing the injection pressures used, increasing the temperature used, a novel gate assembly, a "first-in-first-out" accumulator, and a gas bubble pump to be discussed herein. A further advantage is that the blow factor can be controlled very precisely through the use of a gas bubble pump. The gas is injected precisely at the outlet of a gear pump thereby injecting the gas at a high shear region in the polymer melt. This acts to evenly disperse the bubbles and cause a pulsation effect in the gas in the gas tubes, whereby the gas is alternately compressed and expanded as the gear pump blades pass by a gas injection location. The polymer foam then traverses a shearing region in which the bubbles are reduced in size within the polymer melt. Then the foamed melt is in a state poised to expand due to the pressure inside the bubbles when the polymer foam reaches the heated mold. The furthest extremities of the mold cavities of even the largest parts can therefore be reached with the expansion of the gas bubbles within the molds. The bubbles in the polymer foam nearest the mold walls actually coalesce, are compressed by the expanding foam and break to form a skin region, the thickness of which can be controlled. The remaining foam gradually forms a region of larger bubbles towards the center of the wall of the molded piece. This gradual change in bubble size has been a goal of previous methods but has not been achieved. It is achieved quite precisely with the apparatus and methods described herein. Blow factor of the final product can be controlled, ranging from about 1% to about 80%, preferably from about 20% to about 60%, primarily by adjusting the output of the bubble pump. The method of controlling the blow factor can be further described as melting a solid plastic to form a polymer melt at a preselected temperature; flowing a preselected and controlled amount of the polymer melt into a foaming region; combining a preselected volume of gas bubbles with the polymer melt in the foaming region to form a polymer foam with a preselected blow factor; and flowing the polymer foam through a shearing region having a plurality of alternating extrusion plates and rotating blades, the extrusion plates having a plurality of holes. The extrusion plates can either have the plurality of holes with the same diameter for each plate, or, in the preferred embodiment, each succeeding extrusion plate has a smaller hole size. The method of controlling the blow factor further comprises injecting the polymer foam into a mold, expanding the foam in the mold to form a substantially bubble free skin region and a region where the gas bubble volume increases towards the center of the molded product, and cooling to form the final injection molded product. In one embodiment, the method of reducing the cycle time and controlling the blow factors utilizes a gear pump having an inlet taking melted plastic from an accumulator and having an outlet pressure and volume which can be precisely controlled, the gear pump outlet having gas conduits attached thereto so that gas bubbles may be injected into the polymer melt, forming the polymer foam. The polymer melt foaming apparatus further comprises a gas bubble pump having a plurality of cylinders to form gas bubbles, the cylinders having pistons actuated by cams. Each cylinder of the gas bubble pump has a reed valve by which gas bubbles are released from each cylinder. The gas bubbles travel through the conduits to the melt stream at the outlet of the gear pump. A further feature of the foam injection apparatus and process is a mold gate assembly comprising a gate valve actuating tube; a gate valve nose retention rod coaxial within the gate valve actuating tube; and a hollow gate nose having a plurality of detents on its inner surface, the gate nose removably attached to the retention rod. The hollow gate nose is designed to be removable from the gate assembly and remain with a mold acting as its plug as the mold is removed from the foam injection molding apparatus proper. This apparatus allows polymer foam to expand within the mold, thereby allowing the polymer melt to reach the furthest extremities of the mold cavity, while preventing the polymer foam from actually expanding and leaving the mold cavity itself through the injection gate. The gate valve actuating tube and the retention rod are preferably individually actuated, and the retention rod is preferably adapted to move axially within the actuating tube. The gate nose inner and outer surfaces are generally cylindrical and have detents, the inner detents adapted to receive ball bearings, the outer detents adapted to receive projections on the mold itself. The ball bearings coordinate with the gate nose detents and with the retention rod to give the advantages of removability of the gate nose as explained above. This is an important aspect of the invention as the removable gate nose allows the mold and nose to be removed from the molding station prior to the time the product must be ejected from the mold, without loss of polymer foam, reducing the cycle time substantially. A further advantage of the foam injection molding process is in an accumulator comprising a cylinder, a telescoping inlet section, the inlet section connected to a substantially hollow piston internal to the containing cylinder. The accumulator piston outside surface conforms to the inner contours of the containing cylinder, the piston having a head including adjustable apertures. The apertures are adjusted by use of one or more rotatable adjustment plates having openings mounted adjacent a fixed plate in the piston head with similar openings, thereby allowing variation of the quantity of polymer melt to be expelled from the accumulator as the cross-sectional area of the openings is adjusted. This essentially is a gating mechanism allowing more efficient operation of the entire apparatus since the plasticating extruder can be operated continuously, not in alternating off/on modes. Further features and advantages of the inventive injection molding apparatus and process will be described with reference to the drawing figures as well the explanation which follows. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic diagram of a foam injection molding process in accordance with the present invention; FIG. 2 is a cross-sectional elevation view of an accumulator in accordance with the present invention; FIG. 3 shows a cross-sectional view of the accumulator shown in FIG. 2, showing the apertures in the adjustable plates located in the piston head; FIG. 4 shows a cross-section view of a foaming region and part of a shearing region, showing gear pump, mixing region, shearing region, extrusion plates, and rotating blades of the shearing region; FIG. 5 shows a perspective, partially sectioned view of the polymer foaming and shearing region of a polymer foam injection apparatus; FIG. 6 is a cross-section view of a bubble pump; FIG. 7 shows a cross-section of one cylinder of the bubble pump shown in FIG. 6 showing the reed valve which forms individual bubbles or pulses of gas; FIG. 8 shows a detail cross-section of the gate assembly in accordance with the present invention; FIGS. 9-12 further show the gate assembly of FIG. 8 in various positions of operation, in which the nose piece is shown removable; and FIG. 13 is a partially exploded perspective view of a transition block, showing how the shearing region, transition block, and gate extension tube and corresponding gate assembly may be configured in one embodiment. DESCRIPTION OF PREFERRED EMBODIMENTS FIG. 1 shows the foam injection molding process in its operational and assembled form, albeit in schematic. Similar features in similar drawings figures are given the same numbering. Thus, FIG. 1 shows at 1 the foam injection molding process, having a plasticating extruder 2, which delivers polymer melt at a preselected temperature to an accumulator 3 having an outlet 4. Further shown in schematic in FIG. 1 is foaming region 5, shearing region 7, which takes feed from the foaming region 5, and the mold gate assembly 9. Completing the process is the mold itself 11, which it will be understood can be any size and shape in accordance with the present invention. The process and apparatus of the present invention is however highly suitable for foam injection molding of products having a weight of 25 lbs. or more; the upper limit generally depending on customer demand. Those skilled in the art will recognize that there is essentially no lower limit on part weight that can be injected molded using this apparatus. The size of the finished product from mold 11 is limited only by the practical aspects of handling an extremely large plastic part and by the customer's needs. Again referring to FIG. 1, the process can be described in more detail as having an extruder 2 in which polymer melt is extruded through a die 13, the polymer melt passing through an accumulator inlet pipe 15, the accumulator 3, and an accumulator outlet 4. Further shown in FIG. 1 is an accumulator outlet pipe 17 leading directly to the gear pump 19. (In other preferred embodiments accumulator outlet 17 may be shortened considerably or entirely deleted.) The gear pump has two gears which rotate in the direction of the arrows as shown. Gas bubble pump 21 has a plurality of gas conduits 23 leading therefrom into the outlet of gear pump 19. Polymer melt thus flows through gear pump 19, takes up gas bubbles in the foaming region 5, and then passes through shearing region 7. Shearing region 7 has extrusion plates 25 having holes 67 (see FIG. 5) and rotating blades 27. The spacing between extrusion plates 25 and rotating blades 27 is generally substantially constant, but can vary. In one preferred embodiment, the spacing between extrusion plates 25 and rotating blades 27 is very small, on the order of about 5 mm to about 10 mm. The size and number of holes 67 in extrusion plates 25 are not critical and may vary, not only from extrusion plate to extrusion plate, but within individual extrusion plates 25. Preferably holes 67 range from about 0.030 inch (0.8 mm) to about 0.125 inch (3.5 mm). The particular number of holes 67 depends of course on the diameter of both extrusion plates 25 and holes 67, and is within the skill of persons familiar with fluid mechanics, the only critical aspect being that enough holes are provided so as to not build too great a pressure in as polymer melt flows through the apparatus. The entire shearing region is heated via heating bands 29, thus keeping the entire polymer melt at a preselected temperature as it passes from extruder 2 to mold assembly 11, contrary to methods well known in the art where the melt cools somewhat as it flows into the mold cavity. All component parts of the process which are in contact with the polymer melt are kept at essentially the polymer melt temperature as required under various process conditions which can be determined by the operator. In one preferred embodiment, when polymer foam is formulated using polypropylene, the temperature of the processing apparatus ranges from about 250° F. to about 525° F., more preferably ranging from about 375° F. to about 425° F. Referring now to FIGS. 2 and 3, FIG. 2 shows an elevated cross section of an accumulator in accordance with the present invention. The accumulator, shown generally at 3, has cylinder 16, cup-shaped piston 35, adjustment holes 37 in piston head 35a, and an adjustment plate 38 having holes 38a which can be rotated within the cup-shaped piston 35. Piston 35 generally has an external contour which aligns with the inside surface of accumulator 3. It will be understood that the physical shape and size of the accumulator will vary depending on the processor's needs. This embodiment of the accumulator is completed by having a telescoping inlet section 39 which receives polymer melt from the plasticating extruder 2. As can be seen in FIGS. 1-3, this type of telescoping inlet 39 on accumulator 3 allows the plasticating extruder to be operated continuously and in "first-in-first-out" mode, even should a mold assembly 11 not be on the process as shown in FIG. 1 for an extended period. This allows more efficient operation of the extruder and reduced waste plastic, since operational discontinuities and departure from first-in-first-out flow pattern in injection molding apparatus are well known sources of excessive power consumption and plastic degradation. Adjustment plate 38 can be arranged so that its holes 38a are either fully or partially aligned, or fully unaligned, with holes 37 in piston head 35a (FIG. 3 shows the respective holes fully unaligned for clarity). The alignment is chosen by the operator so that the pressure P 1 is always greater than pressure P 2 (see FIG. 2) when melt flow into mold 11 is greater than melt production from extruder 2, causing piston 35 to move downwards as shown in the arrow of FIG. 2 as gear pump 19 accepts polymer melt from accumulator 3. When one mold has thus been filled to its required amount, and flow to the mold station is stopped, P 2 will be higher than P 1 and piston 35 will move upward as shown by the alternate arrow in FIG. 2. As will be noted by those skilled in the art, a single plate with a single hole can be designed to produce repeated moldings using the same polymer, and this is considered to be within the scope of the invention. FIG. 4 shows a cross section of a mixing region and a foaming region. The embodiments shown in FIG. 4 include a foaming region generally at 5, and an expanded foaming region 6, leading into a shearing region 7. Shearing region 7 includes a shearing region shaft 8, onto which rotating blades 27 are attached. Shearing region shaft 8 passes through extrusion plates 25 and is supported thereby. In further detail, FIG. 4 shows gas conduit plate 14 with hold down bolts 141, which hold the conduit plate to the shear box 12. Gas bubble conduits 23 are shown passing through conduit plate 14, gas conduits 23 having their distal ends at the outlet of gears 18 of gear pump 19. In this way, the gas pulses or bubbles which pass through conduits 23 are injected directly into the polymer melt at the highest shear point, shown at 33 in FIG. 4. This ensures a highly divided gas in the polymer melt, and although the pressure drops somewhat in passing through the expanded region 6, the polymer melt having gas therein then passes through extruder plates 25 having holes therein and then preferably immediately through shearing plates 27. Thus the polymer foam is enduring a series of shearing actions which further reduce the gas bubbles and prevent them from coalescing into larger bubbles or pockets within the polymer melt, which is disadvantageous to the expansion of the gas within the mold. Further shown in FIG. 4 is the extrusion plate holding bolts 26, space bar 28, and heating bands 29, the heating bands maintaining the temperature of the polymer foam as it passes through the shearing region 7. This is an extremely important feature of the invention, in that proper maintenance of temperature, shear, pressure, and gas volume and bubble size as the polymer foam approaches the mold assembly ensures a high degree of control of the blow factor of the final mold product. According to the process of the present invention, the blow factor of the final product can be controlled by adjusting the process temperature, pressure, and size or volume of the gas bubbles in the polymer foam. This degree of control has not heretofore been seen and is quite advantageous in producing large structural parts which do not shrink or warp upon cooling. For example, the thickness of a bubble free region of the final foam injection molded product can be controlled either by increasing the injection pressure through gear pump 19, and increasing the amount of polymer melt pumped. Alternatively, the blow factor may be controlled by increasing the process temperature to increase the bubble free region. Increasing temperature expands the gas and causes bubbles to collapse near the mold wall. Another control alternative comprises decreasing the amount of gas injected to form the polymer foam. These four parameters, process temperature, process pressure, amount of gas in the polymer foam, and size of the gas bubbles, provide a great degree of control of the physical characteristics of the final product. Preferably, the blow factor can be controlled within a range of from about 1% to about 80%. More preferably, the blow factor can be controlled within a range of about 20% to about 60%. Thus, if one knows the specific gravity of the polymer resin to be used, for example, polypropylene ranging from about 0.94 to about 0.99, and if one knows the weight of the particular foam injection molded product that the customer wishes to achieve for particular size, the blow factor can be adjusted to meet the customer weight and size precisely. Not only can the weight and size be precisely controlled however, the structural integrity of the wall sections of the molded piece can be controlled by the blow factor control of the present invention. As the gear pump and bubble pump are positive displacement momentum transfer devices, the quantities of polymer melt and gas to be combined can be precisely controlled, and by means of the shearing region, the gas dispersion in the polymer melt can be controlled to produce a highly uniform polymer foam. This in turn leads to a great degree of control over the bubble free region or the skin region thickness in the final product. A gradual change from a no bubble region to a region of relatively large bubbles is important to prevent shrinkage and warpage of solidified large products. Generally larger parts need thicker outer skins for structure, but since larger parts shrink more, a high degree of control is desirable and achievable with the methods and apparatus described herein. Some further, although perhaps more cumbersome methods of controlling the blow factor can be envisioned, wherein the hole size in the extrusion plates, rotation rate of the rotating blades, and individual spacing between extrusion plates and rotating blades could be adjusted on-line, that is, while injecting foam into a mold. Preferably, the spacing between extrusion plates and rotating blades is minimal and as small as possible without creating unnecessary friction. The typical spacing ranges from about 0 mm to about 20 mm, more preferably from about 0 mm to about 15 mm. Referring now to FIG. 5, a perspective, partially sectioned view of a mixing region 5, shearing region 7 and gas bubble pump 21 is shown. Gas conduits 23 are shown leading from individual cylinders 43 of gas pump 21, ending at individual gas bubble inlet holes 31 around the circumference of gear pump outlet 33, at the point of highest turbulence, pulsing, and folding caused by the blades of gear pump 19. (Note all conduits 23 are not shown for sake of clarity. The conduits 23 that are not shown would lead from further "banks" of cylinders 43, as shown in FIG. 1, but not shown for clarity purposes in FIGS. 4 and 5.) As shown in FIG. 5, shear plates 25 have holes 67 through which polymer foam flows. The important feature shown in FIG. 5 is the extrusion plate/rotating blade spacing 69 (shown essentially as 0 in FIG. 5). Although the spacing 69 can be any degree ranging from about 0 to about 20 mm, it is preferred that the rotating blades are essentially right up against the extrusion plates 25. In this embodiment, it can be seen that as the polymer melt having gas bubbles therein flows through extrusion plates 25 having somewhat smaller holes than the initial gas bubble size in the melt, the polymer foam will immediately pass through a high shear region precipitated by the rotating blades 27. Although most polymer melts will exhibit an increase in viscosity due to the high shear, the entire apparatus is kept heated by heating bands 29, thus keeping the viscosity at a controllable level. The advantage of having small gas bubble sizes overshadows the disadvantage of any increase in viscosity. Typically, the bubbles have volumes ranging from 0.01 cc to about 0.20 cc, more preferably ranging from about 0.01 cc to about 0.10 cc. Gases used in the process for injection into the polymer melt may be inert to or react with the polymer melt, and may be a single gas or combination of gases. In some cases gases or gas mixtures which react in some way with the polymer melt may be disadvantageous. Oxygen, for example, degrades most polymers by oxidation, especially polymers having double bonds, ether linkages, or tertiary carbons. If the prevention of oxidation is not critical, ordinary shop air can be used as the gas. Bottled gases, commercially available meeting known specifications, such as nitrogen, may be preferred in some applications. The gases may contain small amounts of moisture; however, if the polymer has hydrolyzable linkages such as urethanes and aliphatic ester groups, care must be taken to eliminate moisture. Preferred gases have little moisture and can be considered substantially dry. In most cases, shop air is the preferred gas because of its general availability to run air tools and because it is relatively inexpensive compared with bottled gases. The gas bubble pump of the present invention is shown in one embodiment in FIG. 6 in cross section. At 41 is shown gas outlets from bubble pump 21 comprising eight gas conduits 23, as shown in FIGS. 4 and 5. Bubble pump 21 has cylinders 43, the cylinders having cylinder bore 44 and pistons 45. Pistons 45 reciprocate in cylinder bores 44 when cam 47 is rotated on cam shaft 48. Each cylinder 43 has a cylinder discharge plate 49, shown more clearly in FIG. 7. As each individual piston 45 moves towards individual discharge plate 49, gas is compressed and then is passed through cylinder outlets 55 and through conduits 23 and on toward the mixing region. With reference to FIG. 7, is can be seen that cylinder discharge plate 49 has an elastic flap 51 forming a reed valve in each cylinder. As cam 47 rotates, each piston forces gas to compress within each cylinder 43 until flap 51 is caused to move from its initial sealed position to an extended position thereby releasing gas. The gas released is not continuous but is rather in a pulse or bubble form. The degree of control of elasticity of flap 51 allows very precise control of pulse volume going into the polymer foam. Further, the radial design allows gas to be put into the polymer melt as pulses at different times and locations at gear pump outlet 33. Such a high degree of control is not known or disclosed in other foaming apparatus to the knowledge of the inventor. The discharge pressure of the bubble pump can range from about 300 psi to about 1000 psi, with a range of about 300 psi to about 500 psi being preferable. Further, the bubbles preferably have a volume ranging from about 0.01 cc to about 0.20 cc, more preferably ranging from about 0.01 cc to about 0.10 cc. Therefore, any materials of construction which can meet these requirements have utility for the present bubble pump construction. For example, material of choice for the cylinders is regular carbon steel, while the reed valves can be metal alloy, copper, or plastic such as polypropylene or high strength fluoropolymers, such as polytetrafluoroethylene. Referring now to FIG. 8, a gate assembly is shown having gate extension tube 76 which axially contains therein the mechanism which operates retention and ejection of gate nose 77. Gate nose 77 is removably attached to gate nose arbor 78, the gate nose arbor being permanently attached to a gate valve actuating tube 81 via bolts 81a. Gate valve actuating tube 81 correspondingly has a gate head 82, with an expanded hollow section whose function is to be described herein. Gate head expanded section 82a has coaxially and movably contained therein gate valve nose retention rod 83. Gasket 84 is provided to seal gate valve actuating tube 81 against gate plate 80 as described below. As shown in FIG. 8, gate nose 77 has internal grooves 85 on its inner surface, these grooves allowing movement of ball bearings 87 into and out thereof. Ball bearings 87 are also movable within gate nose arbor 78 in a fashion to be further described with reference to FIGS. 9 through 12. Various other gaskets have similar functions and are shown collectively as 88. Mold retaining pins 93 hold a mold 150 having polymer foam passage 151 onto gate plate 80, gate plate 80 being held to gate extension tube flange 76a via bolts 86. Other parts of the molding station shown in FIG. 8 include a mold gate 95 and mold gate adaptor plate and bolting assembly 97. Pivot bolt assembly 99 allows the mold gate adaptor plate and bolting assembly to be pivoted away from the mold after the mold is removed from the injection molding machine. Heating bands 29 are shown in this embodiment surrounding the entire circumference of gate extension tube 76. Now referring to FIGS. 9 through 12, the operation of the mold gate assembly is described. The operation can be described in four repeatable steps for each mold to be used in the process. Gate nose 77 is designed to fit in all of the mold gate adaptor plates 97 used in the process so that different sizes of gate nose 77 need not be fashioned for different size molds. (For clarity purposes, only detail reference numerals are given in FIG. 9, it being understood that the same numerals are used for the same parts in FIGS. 10-12.) In FIG. 9, note that gate valve nose retention rod 83 is moved axially in the vertical direction coaxial within gate valve actuating tube 81, that is, radial extensions 83a in gate nose retention rod 83 are abutted against notch 81b of gate valve actuating tube 81. In this first position, note that ball bearings 87 have moved to a position where at least part of the ball bearings lie within the inner surface of the internal groove 85 of gate nose 77. (Note that gate nose arbor 78 has through holes through which ball bearings 87 move, the through holes are not numbered for clarity.) As the gate valve actuating tube 81 and gate valve nose retention rod 83 are simultaneously moved axially stopping the polymer foam flow in the direction of the arrow shown in FIG. 9, gate nose external grooves 85a on the outer surface of gate nose 77 engages mold retaining pin projections 94 on mold retaining pins 93, as shown in FIG. 10. FIG. 9 represents the position of the mold gate assembly when polymer foam is flowing into a mold, whereas FIG. 10 represents the position of the gate assembly when polymer foam has partially filled a mold and it is desired to terminate polymer foam flow to the mold, using sealing gaskets 84 and 88. This stage usually occurs when the mold cavity has attained about 60% to about 95% of complete mold fill, more preferably about 75% to about 90% mold fill volume. Gas pressure within the gas bubbles causes the foam to expand and fill the remainder of the mold cavity ("free rise"). The free rise can be adjusted precisely by the operator so that a variety of skin thicknesses and blow factors can be obtained using the same apparatus. As shown in FIG. 10, gate valve nose retention rod 83 has not changed position axially within gate valve actuating tube 81. Referring now to FIGS. 11 and 12, gate valve nose retention rod 83 is now moved in the direction of the arrow shown in FIG. 11. This movement causes gate valve nose retention rod radial depressions 83b (FIG. 9) to move into a position to partially accept ball bearings 87. As discussed previously, ball bearings 87 move through holes 85 in gate nose arbor 78. In the positions of FIGS. 11 and 12, ball bearings 87 now have none of their diameter within gate nose internal groove 85, and simultaneously gate nose external grooves 85a, which are on the outside surface of gate nose 77, are engaged by mold retaining pin projections 94 (FIG. 9). Progressing from FIG. 11 to FIG. 12, the mold gate assembly 95 and mold 150 (not shown) are now ready to be removed from the machine with the mold having polymer foam therein filled to a preselected percentage of capacity. Mold gate assembly 95 is moved in the direction of arrows shown in FIG. 12. Gate nose retention rod radial extensions 83a are moved to a position away from gate valve actuating tube notch 81b (FIG. 9). Thus, as mold gate assembly 95 and mold 150 are pulled away from the injection molding machine proper, gate nose 77 remains with the mold gate 95. As a final step in the sequence, a new gate nose 77 (not shown) may be inserted onto gate nose arbor 78, a new and different mold assembly attached to the machine, and gate valve actuating tube 81 and gate valve nose retention rod 83 moved in the direction opposite to the arrow shown in FIG. 9 so that polymer foam may flow into a new mold, and so on. The exact configuration of the connection between the mixing/shearing region and the gate extension tube 76 is not critical, although gate extension tube 76 typically projects at a substantially 90° angle to the shearing region shaft 8. Gate extension tube 76 and gate valve actuating tube 81, etc. generally will lie in a plane parallel to that of the mixing/shearing region, this being merely for accessible arrangement of the drive means of gate valve actuating tube 81, gate valve nose retention rod 83, and shearing region shaft 8. The drive mechanisms for the mold gate assembly and the shearing region are well known in the art and are generally purchased items. For example, the shearing region shaft can be driven by a typical motor, gear box, and drive belt assembly. This arrangement will allow for controlling the rate of rotation of the shearing region drive shaft 8, and thus the rotating blades 27. Further, gate valve actuating tube 81 and gate valve nose retention rod 83 may be actuated by coaxially moving hydraulic pistons, the hydraulic mechanisms generally being purchased items. The materials of construction of pieces such as the gate extension tube, gate valve actuating tube, gate nose retention rod, etc. are well known in the art and are typically carbon steel or one of the many varieties of stainless steel, such as a 316 stainless. A typical connector region between the shearing region and the mold gate assembly is shown in FIG. 13 generally at transition block 100. In FIG. 13, polymer foam passes through shearing region outlet 103 and subsequently through transition block 100, which is substantially hollow. Polymer foam then moves through transition block outlet 105 and on into gate extension tube 76. Gate extension tube 76, having flanges 76a and b, can then be connected to transition block 100 and mold gate assembly 95. Gate valve actuating tube 81 has a diameter which is smaller than gate extension tube 76, allowing polymer foam to flow around gate valve actuating tube 81. As can be seen in FIG. 13, the arrangement of transition block 100 allows positioning of drive means for shearing region shaft 8 and gate valve actuating tube 81 and gate valve nose retention rod 83 to be positioned accordingly, for ease of operation and maintenance. (The drivers for the assemblies are not shown in FIG. 13, being well known in the art.) In the embodiment shown in FIG. 13, transition block 100 is made of aluminum, although other materials, such as carbon cast iron, steel or stainless steel may be appropriate. Aluminum has the advantages of being easily machinable and is suitable for most purposes because of its quickness in changing temperatures due to its inherently excellent thermal properties. Transition block flange 111 and outlet 113 have a diameter similar or equal to the internal diameter of gate extension tube 76, allowing polymer foam to flow through transition block 100 and through gate extension tube 76, allowing gate valve actuating tube to move coaxially therethrough. Transition block flange 111 has bolt holes 112 which mate with holes 107 and holes 109 in the gate extension tube flange and transition block, respectively. It will be noted by those skilled in the art that the placement of the bolts can be equally spaced or nonequally spaced according to the pressures the manufacturer wishes to use in the process and to prevent leakage of polymer foam. It will also be noted that the relative angle between the gate assembly, that is, the gate valve actuating tube 81, etc., and the shearing region shaft 8 can vary to angles other than substantially 90°. The materials of construction of the various component parts of the injection molding apparatus described herein are similar to those generally used in injection molding machines. Similarly, materials used in the bubble pump may be any of those materials used with compression equipment as known in the art. The accumulator 3, piston 35, telescoping inlet 39, and the various other parts of accumulator 3 may be made of any material which can withstand the processing temperatures and pressures used for the polymer foam injection process. Generally the materials of preference are carbon steel due to its low cost, although more exotic alloys may be required, such as stainless and high chrome steels. Again, the choice of materials depends on the particular process, although when processing polypropylene into a polymer foam, the choice of material is generally carbon steel. Many items are commercially available: gear pump, gaskets, ball bearings, motors, gear boxes, gear box and motor couplings, heater bands, drive belts and pulleys, and reed valves being examples. The foregoing description is offered primarily for purposes of illustration. It will be readily apparent to those skilled in the art that further modifications, variations and the like may be introduced in the materials, configurations, arrangements and shapes of the various elements of the structure and process without departing from the spirit and scope of the invention. For example, an automated, "closed-loop" control system could be used rather than an "open-loop," human controlled system for controlling blow factor and reducing cycle time of the process described herein. Suitable closed-loop systems might include a supervisory control computer, which takes input information such as polymer foam and mold temperatures, gas bubble content, and polymer foam viscosity, and adjusts the rotation speed of the rotating blades in the shearing region, or the output from the gas bubble pump. Other variations of control schemes can be envisioned and are deemed within the scope of the appended claims.

Foam thermoplastic injection molding apparatus and method produces structurally superior foam injection molded products. The process includes plasticating solid polymer to a polymer melt; accumulating the melt in an accumulator having a telescoping inlet, which allows the first melt which enters to be the first to leave the accumulator; combining a preselected amount of melt with a preselected amount of gas in bubble form to form homogenized polymer foam; shearing the homogenized polymer foam to reduce the size of gas bubbles; and injecting the polymer foam through a special gate assembly into a mold. The gate assembly has a removable nose which remains with the mold, allowing the foam to expand within the mold but not allowing the foam to escape the mold. The process and apparatus allow low molded-in stress products to be produced, and can process recyclable thermoplastics, either single materials or mixtures. Thus, no segregation of materials is required.

BACKGROUND OF THE INVENTION 1. Field of the Invention The invention relates to certain 2-phenylpiperidine compounds, more particularly to certain 2-[2-hydroxy-4-(ZW-substituted)phenyl]piperidines of the formula ##STR3## or a pharmaceutically acceptable acid addition salt thereof, useful as CNS agents, especially as analgesics, antiemetic and antidiarrheal agents for use in mammals, including man, methods for their pharmaceutical compositions containing them and intermediates therefore. 2. Description of the Prior Art Despite the current availability of a number of analgesic agents, the search for new and improved agents continues, thus pointing to the lack of an agent useful for the control of broad levels of pain and accompanied by a minimum of side-effects. The most commonly used agent, aspirin, is of no practical value for the control of severe pain and is known to exhibit various undesirable side-effects. Other, more potent analgesics such as d-propoxyphene, codeine, and morphine, possess addictive liability. The need for improved and potent analgesics is, therefore, evident. More recently, great interest in cannabinol-type compounds as analgesic agents has been exhibited, see, for example, R. Mechoulam, Ed., "Marijuana Chemistry, Pharmacology, Metabolism and Clinical Effects", Academic Press, New York, N.Y., 1973; Mechoulam, et al., Chemical Reviews, 76, 75-112 (1976). U.S. Pat. No. 4,147,872, issued Apr. 23, 1979, discloses a series of 3-[2-hydroxy-4-(substituted)phenyl]piperidine CNS agents of the formula ##STR4## where R 2 and R 3 have certain values in common with R 2 and R 3 , respectively, as defined for the instant compounds of formula (I). The compounds of formula (II) are active analgesics, tranquilizers, sedatives and antianxiety agents for use in mammals, and/or as anticonvulsants, diuretics and antidiarrheal agents. U.S. Pat. No. 4,306,097, issued Dec. 15, 1981, discloses 3-[2-hydroxy-4-(substituted)phenyl]cycloalkanol analgesic agents. SUMMARY OF THE INVENTION It has now been found that certain 2-[2-hydroxy-4-(substituted)phenyl]piperidines and derivatives thereof are effective CNS agents, especially as analgesics, tranquilizers, sedatives and antianxiety agents in mammals, including humans and/or anticonvulsants, diuretics and antidiarrheal agents in mammals, including man. They are especially effective in said mammals as analgesics, antidiarrheals and as agents for treatment and prevention of emesis and nausea, especially that induced by antineoplastic drugs. Said invention compounds, which are nonnarcotic and free of addiction liability, are of the formula ##STR5## or a pharmaceutically acceptable acid addition salt thereof, wherein R 1 is H, benzyl, benzoyl, formyl, (C 2 -C 7 )alkanoyl or CO(CH 2 ) p NR 4 R 5 where p is zero or is 1-4 and R 4 and R 5 are each H or (C 1 -C 4 )alkyl or taken together with the nitrogen atom to which they are attached, they form a piperidino, pyrrolo, pyrrolidino, morpholino or N-[(C 1 -C 4 )alkyl]piperazino group; R 2 is H, formyl, (C 1 -C 6 )alkyl, (C 2 -C 6 )alkenyl, (C 2 -C 6 )alkynyl, (C 2 -C 7 )hydroxyalkyl, (C 2 -C 7 )alkylcarbonyl, (C 3 -C 7 )alkenylcarbonyl, (C 3 -C 7 )alkynylcarbonyl, (C 1 -C 6 )alkylsulfonyl, (C 2 -C 7 )alkoxycarbonyl or (C 2 -C 7 )hydroxyalkylcarbonyl; R 3 is two atoms of hydrogen, a carbonyl oxygen atom, ##STR6## Z is (C 1 -C 13 )alkylene or -(alk 1 ) m -O-(alk 2 ) n - where each of (alk 1 ) and (alk 2 ) is (C 1 -C 13 )alkylene with the proviso that the sum of carbon atoms in (alk 1 ) plus (alk 2 ) is not greater than 13, and each of m and n is 0 or 1; and W is hydrogen, pyridyl or W 1 C 6 H 4 where W 1 is H, F or Cl. Particularly preferred compounds of formula (I) are those wherein: R 1 is hydrogen or alkanoyl, especially hydrogen or acetyl; R 2 is (C 1 -C 6 )alkyl, (C 2 -C 6 )alkenyl, (C 2 -C 6 )alkynyl, (C 2 -C 7 )alkylcarbonyl, (C 2 -C 7 )alkoxycarbonyl or (C 1 -C 6 )alkylsulfonyl, especially n-propyl, 2-propenyl, 2-propynyl, (C 2 -C 5 )alkylcarbonyl or (C 2 -C 4 )alkoxycarbonyl; R 3 is ##STR7## Z is said alkylene or O(alk 2 ); and W is hydrogen or phenyl; especially preferred ZW are C(CH 3 ) 2 (CH 2 ) 5 CH 3 or OCH(CH 3 )(CH 2 ) 3 C 6 H 5 . More particularly preferred compounds of the invention because of their enhanced biological activity relative to other compounds described herein are the cis isomers of the formula ##STR8## where R 2 is as shown in the table. R 2 CH 2 CH 2 CH 3 CH 2 CH═CH 2 CH 2 C.tbd.CH CO 2 CH 3 CO 2 CH 2 CH 3 SO 2 CH 3 COCH 3 COCH 2 CH 3 COCH 2 CH 2 CH 3 CO(CH 2 ) 3 CH 3 Most particularly preferred such compounds are N-butyryl cis-2-[4-(1,1-dimethylheptyl)-2-hydroxyphenyl]-4-piperidinol and N-ethoxycarbonyl cis-2-[4-(1,1-dimethylheptyl)-2-hydroxyphenyl]-4-piperidinol. More particularly preferred compounds of the invention which are useful as intermediates in preparation of the above biologically active compounds, are of the formula ##STR9## where R 2 and ZW are as previously defined. Especially preferred such intermediates are those wherein R 2 is COOCH 3 or COOC 2 H 5 and ZW is C(CH 3 ) 2 (CH 2 ) 5 CH 3 or OCH(CH 3 )(CH 2 ) 3 C 6 H 5 . Also included in the present invention are the pharmaceutically acceptable acid addition salts of the compounds of formula (I) which contain a basic group. In compounds having two or more basic groups present, such as those wherein W is pyridyl and/or R 1 represents a basic ester moiety, polyacid addition salts are possible. Representative of such pharmaceutically acceptable acid addition salts are the mineral acid salts such as the hydrochloride, hydrobromide, sulfate, phosphate, nitrate; organic acid salts such as the citrate, acetate, sulfosalicylate, tartrate, glycolate, malate, malonate, maleate, pamoate, salicylate, stearate, phthalate, succinate, gluconate, 2-hydroxy-3-napthoate, lactate, mandelate and methanesulfonate. Compounds of formula (I) contain an asymmetric center at the 2-position and, when R 3 is a secondary alcohol group, at the 4-position. They may contain additional centers of asymmetry in the R 1 , R 2 and ZW substituents. For convenience, the above formulae depict the racemic compounds. However, the above formulae are considered to be generic and embracive of racemic modifications of the compounds of the invention, the diastereomeric mixtures, the pure enantiomers and diastereomers thereof. The utility of the racemic mixture, the diastereomeric mixture as well as the pure enantiomers and diastereomers is determined by the biological evaluation procedures described below. As mentioned above, the compounds of the invention are particularly useful as analgesics, antidiarrheals and as antiemetic and antinausea agents for use in mammals, including man. The invention further provides a method for producing analgesia in mammals and a method for prevention and treatment of nausea in a mammal subject to nausea, in each case by oral or parenteral administration of an effective amount of a compound of formula (I) or a pharmaceutically acceptable salt. Also provided are pharmaceutical compositions for use as analgesics, as well as those suitable for use in prevention and treatment of nausea, comprising an effective amount of compound of the invention and a pharmaceutically acceptable carrier. DETAILED DESCRIPTION OF THE INVENTION The compounds of this invention having formula (I) wherein R 3 is a carbonyl oxygen atom are prepared from the appropriate hydroxy-protected 2-bromo 5-(Z-W substituted)phenol. Suitable hydroxy protecting groups are those which do not interfere with subsequent reactions and which can be removed under conditions which do not cause undesired reactions at other sites of said compounds or of products produced therefrom. Representative of such protective groups are methyl, ethyl, benzyl or substituted benzyl wherein the substituent is, for example, alkyl having from one to four carbon atoms, halo (Cl, Br, F, I) and alkoxy having from one to four carbon atoms. The exact chemical structure of the protecting group is not critical to this invention since its importance resides in its ability to perform in the manner described above. The selection and identification of appropriate protecting groups can easily and readily be made by one skilled in the art. The suitability and effectiveness of a group as a hydroxy protecting group are determined by employing such a group in the herein-illustrated reaction sequences. It should, therefore, be a group which is easily removed to regenerate the hydroxy groups. The benzyl group is a preferred group since it can be removed by catalytic hydrogenolysis or acid hydrolysis. Detailed procedures for preparing the hydroxy-protected 2-bromo-5(ZW-substituted)phenol starting materials, including those of formula (V) wherein the hydroxy-protecting group is benzyl, are described in U.S. Pat. Nos. 4,147,872 and 4,306,097 each of which are hereby incorporated herein by reference. The protected 2-bromo-5-(ZW-substituted)phenol (V) is subjected to a copper catalyzed Grignard reaction in a reaction-inert solvent with the appropriate N-R 2 -substituted-4-oxo-1,2,3,4-tetrahydropyridine (IV) as shown in Scheme A for the preferred case where the hydroxy protecting group is benzyl. Suitable reaction-inert solvents are cyclic and acyclic ethers such as, for example, tetrahydrofuran, dioxane, diethyl ether and ethylene glycol dimethyl ether. ##STR10## The Grignard reagent is formed in known manner, as, for example, by refluxing a mixture of one molar proportion of the bromo reactant and two molar proportions of magnesium in a reaction-inert solvent, e.g., tetrahydrofuran at reflux temperature. The resulting mixture is then cooled to about -20° to 25° C. and a cuprous salt, for example, cuprous iodide or cuprous bromide, added in a catalytic amount. The appropriate 4-oxo-1,2,3,4-tetrahydropyridine[2,3-dihydro-4-(1H)pyridinone (IV)] is then added at a temperature of from about -20° to 0° C. The product of the Grignard reaction of formula (III) can then be treated with an appropriate reagent to remove the protecting group. If desired, the benzyl group on the phenolic hydroxy group is conveniently removed by catalytic hydrogenation over palladium-on-carbon. Alternatively, the phenolic benzyl group can be removed by acid hydrolysis using, for example, trifluoroacetic acid. The preferred intermediate (III) can also be reacted under reducing conditions known to convert ketones to secondary alcohol groups. For example, catalytic hydrogenation over a noble metal catalyst, for example, platinum, palladium or nickel; or reduction with an alkali metal hydride, for example, lithium aluminum hydride, sodium borohydride, potassium borohydride. A preferred reducing agent for this conversion is sodium borohydride because it gives rise to a predominantly di-cis-product (VI). The reaction is carried out in a polar solvent, for example, a lower alcohol such as methanol, ethanol or 2-propanol; water, an ether such as diethyl ether, tetrahydrofuran, diglyme or mixtures thereof; and at a temperature of from about -70° C. up to the reflux temperature of the solvent. An especially preferred temperature is in the range of from -50° to 25° C., at which temperature the reaction is substantially complete in a few hours. The resulting 4-piperidinol is separated by known methods and purified, if desired, for example, by silica gel column chromatography. Alternatively, the intermediate ketones of formula (III) can be reduced to the corresponding piperidine derivatives of formula (IX) by methods known to reduce ketones to hydrocarbons. Examples of such methods are the well known Clemmensen method employing amalgamated zinc and hydrochloric acid (see e.g., "Organic Reactions", Academic Press, New York, Vol. 1, 1942, page 155) and the Wolff-Kishner reduction employing hydrazine and a strong base such as potassium hydroxide [see, e.g., "Organic Reactions", Vol. 4, page 378 (1948)]. A particularly preferred method is the Wolff-Kishner reduction employing hydrazine hydrate and potassium hydroxide in ethylene glycol as solvent. A preferred temperature for this reaction is from 50° to 250° C., especially 100°-200° C., at which temperature the reaction is complete within a few hours. The benzyl ether of the 2-phenylpiperidine compound of formula (IX) is then isolated by methods well known in the art and the benzyl group removed by methods described above. As mentioned above, the benzyl hydroxy-protecting group such as that present in the above compounds of formulae (III) or (VI), for example, are preferably removed by catalytic hydrogenolysis. The hydrogenolysis of such compounds is ordinarily carried out by means of hydrogen in the presence of a noble metal catalyst. Examples of noble metals which may be employed are nickel, palladium, platinum and rhodium. The catalyst is ordinarily employed in catalytic amounts, e.g., from about 0.01 to 10 weight-percent and preferably from about 0.1 to 2.5 weight-percent, based on the starting compound, e.g. the benzyl ether (III) or (VI). It is often convenient to suspend the catalyst on an inert support, a particularly preferred catalyst is palladium suspended on an inert support such as carbon. One convenient method of carrying out this transformation is to stir or shake a solution of the starting compound, e.g. (III) or (VI), under an atmosphere of hydrogen in the presence of one of the above noble metal catalysts. Suitable solvents for this hydrogenolysis reaction are those which substantially dissolve the starting compound but which do not themselves suffer hydrogenation or hydrogenolysis. Examples of such solvents include the lower alkanols such as methanol, ethanol and isopropanol; ethers such as diethyl ether, tetrahydrofuran, dioxane and 1,2-dimethoxyethane; low molecular weight esters such as ethyl acetate and butyl acetate; tertiary amides such as N,N-dimethylformamide, N,N-dimethylacetamide and N-methylpyrrolidone; and mixtures thereof. Introduction of the hydrogen gas into the reaction medium is usually accomplished by carrying out the reaction in a sealed vessel, containing the starting compound, the solvent, the catalyst and the hydrogen. The pressure inside the reaction vessel can vary from about 1 to about 100 kg/cm 2 . The preferred pressure range, when the atmosphere inside the reaction vessel is substantially pure hydrogen, is from about 2 to about 5 kg/cm 2 . The hydrogenolysis is generally run at a temperature of from about 0° to about 60° C., and preferably from about 25° to about 50° C. Utilizing the preferred temperature and pressure values, hydrogenolysis generally takes place in a few hours, e.g., from about 2 hours to about 24 hours. The product is then isolated by standard methods known in the art, e.g., filtration to remove the catalyst and evaporation of solvent or partitioning between water and a water immiscible solvent and evaporation of the dried extract. As illustrated in Scheme B, above, an N-alkoxycarbonyl intermediate of formula (X) can be subjected to hydrolysis and decarboxylation to provide the corresponding base of formula (XI). The free base can then be alkylated or acylated by reaction with a compound of formula R 2 L wherein R 2 may have any of the values given above, but preferably is not H, and L is a leaving group, to provide the corresponding compound of formula (VI). The hydrolysis and decarboxylation of the N-alkoxycarbonyl compounds such as the N-ethoxycarbonyl compound of formula (X) is carried out in an aqueous solvent, and a strong base. Preferred solvents for this conversion are a lower alcohol, e.g., methanol, ethanol or isopropanol; a glycol such as ethylene glycol or diethylene glycol, water or mixtures thereof. Preferred as strong base for the hydrolysis are potassium hydroxide, sodium hydroxide, calcium hydroxide or potassium carbonate. In an especially preferred such method the N-ethoxycarbonyl compound of formula (X) in ethanol is added to ethylene glycol containing a molar excess of potassium hydroxide and water. The mixture is evaporated to remove alcohol and then heated at reflux for 1-2 days. The decarboxylated product of formula (XI) is then isolated, e.g. by extraction and purified by column chromatography, if desired. The 2-phenyl-4-(R 3 substituted)piperidine free base, for example that of formula (XI), may then be converted to the analogous N-alkyl, N-alkenyl, N-alkynyl, N-alkylsulfonyl or N-acyl derivative of formula (I, R 1 =H) by well known alkylation, sulfonylation or acylation techniques, as shown in Scheme B, above. For the reagents of formula R 2 L preferred leaving groups, L, are the halogens, Cl, Br, or I; HO or acyloxy. For these reagents wherein R 2 is said alkyl, alkenyl, alkynyl, hydroxyalkyl, alkylcarbonyl, alkenylcarbonyl, alkynylcarbonyl, hydroxyalkylcarbonyl or alkylsulfonyl, an especially preferred leaving group is Cl, Br or I. When R 2 is said alkylcarbonyl, alkenylcarbonyl, alkynylcarbonyl or hydroxyalkylcarbonyl, preferred leaving groups, L, are OH or acyloxy where said acyl is the residue of an acid anhydride or a mixed anhydride. The reactions of reagents R 2 L with free bases such as those of formula (X) for example, are carried out by methods well known in the art for alkylation or acylation of secondary amines to form tertiary amines or amides, respectively. For acylation of the piperidine free bases of formula (XI) the acylating agent, R 2 L, is preferably the appropriate carboxylic acid or activated derivative thereof, for example, the acid chloride, acid bromide or acid anhydride. The reaction is preferably carried out in the presence of a reaction inert solvent, preferably, methylene chloride, chloroform, ethyl ether, tetrahydrofuran, acetone or acetonitrile and optionally in the presence of an acid acceptor which may be organic or inorganic. Suitable binding agents are, for example, the alkali metal carbonates and hydroxides, pyridine, 4-N,N-dimethylaminopyridine, triethylamine and N-methylmorpholine. The acylation is preferably carried out at a temperature of from 0° up the the reflux temperature of the solvent. When the acylation agent, R 2 L, is a carboxylic acid it is preferred to carry out the reaction in the presence of one of the condensing agents known to be useful in forming amides, e.g., dicyclohexylcarbodiimide. When the piperidine free base (XI) is to be alkylated with the reagent R 2 L an especially preferred reagent is R 2 Cl or R 2 Br. The reaction is conducted in a solvent, e.g. an alkanol such as ethanol, n-butanol or isoamylalcohol at a temperature of from about room temperature up to the reflux temperature of the solvent. An acid acceptor, e.g. those set forth above and especially potassium carbonate or triethylamine, is also preferably employed in this reaction. An alternative method for obtaining invention compounds wherein R 2 is alkyl or hydroxyalkyl is to carry out the above described acylation of, e.g. a compound of formula (XI), followed by reduction of the resulting amide of formula (XII) with, e.g. lithium aluminum hydride, to provide the desired compound of formula (XII) wherein R 2 is said alkyl, alkenyl or alkynyl. When the acylation is carried out with an hydroxyalkyl carboxylic acid, the hydroxy group of which is protected, or an activated derivative thereof, e.g. a benzyloxyalkyl carboxylic acid or an activated derivative such as the acid chloride, and the resulting amide is reduced with lithium aluminum hydride and the benzyl protecting groups subsequently removed, e.g. by hydrogenolysis, the product obtained is of formula (I) wherein R 1 is hydrogen and R 2 is hydroxyalkyl. The requisite N-R 2 -substituted 4-oxo-1,2,3,4-tetrahydropyridine starting materials of formula (IV) are obtained by methods described by Haider et al., Helvetica Chimica Acta, 58, 1287 (1975) and in references set forth therein. A preferred method is by sodium borohydride reduction of the corresponding N-R 2 -substituted-pyridone in an alcoholic solvent, e.g. t-butanol. At 25° C. the reaction proceeds in high yield after 2 days, and the product is isolated by standard methods. ##STR11## A preferred 4-oxopyridone reagent for this reaction is one where R 2 is alkoxycarbonyl, e.g. ethoxycarbonyl. Esters of compounds of formula (I) wherein R 1 is benzoyl, alkanoyl or --CO--(CH 2 ) p --NR 4 R 5 are readily prepared by reacting forumla (I) compounds wherein R 1 is hydrogen with benzoic acid, the appropriate alkanoic acid or acid of formula HOOC--(CH 2 ) p --NR 4 R 5 in the presence of a condensing agent such as dicyclohexylcarbodiimide. Alternatively, they are prepared by reaction of the formula (I) (R 1 =H) compound with the appropriate acid chloride or anhydride, e.g., benzoyl chloride, acetyl chloride or acetic anhydride, in the presence of a base such as pyridine. The presence of a basic group in the ester moiety (OR 1 ) in the compounds of this invention permits formation of acid-addition salts involving said basic group. When the herein described basic esters are prepared via condensation of the appropriate amino acid hydrochloride (or other acid addition salt) with the appropriate compound of formula (I) in the presence of a condensing agent, the hydrochloride salt of the basic ester is produced. Careful neutralization affords the free base. The free base form can then be converted to other acid addition salts by known procedures. Acid addition salts can, of course, as those skilled in the art will recognize, be formed with the invention compounds of formula (I) having a basic nitrogen moiety. Such salts are prepared by standard procedures. The basic ester derivatives of these piperidine compounds are, of course, able to form mono- or di-acid addition salts because of their dibasic functionality. The analgesic properties of the compounds of this invention are determined by tests using thermal nociceptive stimuli, such as the mouse tail flick procedure, or chemical nociceptive stimuli, such as measuring the ability of a compound to suppress phenylbenzoquinone irritant-induced writhing in mice. These tests and others are described below. TESTS USING THERMAL NOCICEPTIVE STIMULI (a) Mouse Hot Plate Analgesic Testing The method used is modified after Woolfe and MacDonald, J. Pharmacol. Exp. Ther., 80, 300-307 (1944). A controlled heat stimulus is applied to the feet of mice on a 1/8" thick aluminum plate. A 250 watt reflector infrared heat lamp is placed under the bottom of the aluminum plate. A thermal regulator, connected to thermistors on the plate surface, programs the heat lamp to maintain a constant temperature of 57° C. Each mouse is dropped into a glass cylinder (61/2" diameter) resting on the hot plate, and timing is begun when the animal's feet touch the plate. At 0.5 and 2 hours after treatment with the test compound, the mouse is observed for the first "flicking" movements of one or both hind feet, or until 10 seconds elapse without such movements. Morphine has an MPE 50 =4-5.6 mg/kg (s.c.). (b) Mouse Tail Flick Analgesic Testing Tail flick testing in mice is modified after D'Amour and Smith, J. Pharmacol. Exp. Ther., 72, 74-79 (1941), using controlled high intensity heat applied to the tail. Each mouse is placed in a snug-fitting metal cylinder, with the tail protruding through one end. This cylinder is arranged so that the tail lies flat over a concealed heat lamp. At the onset of testing, an aluminum flag over the lamp is drawn back, allowing the light beam to pass through the slit and focus onto the end of the tail. A timer is simultaneously activated. The latency of a sudden flick of the tail is ascertained. Untreated mice usually react within 3-4 seconds after exposure to the lamp. The end point for protection is 10 seconds. Each mouse is tested at 0.5 and 2 hours after treatment with morphine and the test compound. Morphine has an MPE 50 of 3.2-5.6 mg/kg (s.c.). (c) Tail Immersion Procedure The method is a modification of the receptacle procedure developed by Benbasset, et. al., Arch. int. Pharmacodyn., 122, 434 (1959). Male albino mice (19-21 g) of the Charles River CD-1 strain are weighed and marked for identification. Five animals are normally used in each drug treatment group with each animal serving as its own control. For general screening purposes, new test agents are first administered at a dose of 56 mg/kg intraperitoneally or subcutaneously, delivered in a volume of 10 ml/kg. Preceding drug treatment and at 0.5 and 2 hours post drug, each animal is placed in the cylinder. Each cylinder is provided with holes to allow for adequate ventilation and is closed by a round nylon plug through which the animal's tail protrudes. The cylinder is held in an upright position and the tail is completely immersed in the constant temperature waterbath (56° C.). The endpoint for each trail is an energetic jerk or twitch of the tail coupled with a motor response. In some cases, the endpoint may be less vigorous post drug. To prevent undue tissue damage, the trail is terminated and the tail removed from the waterbath within 10 seconds. The response latency is recorded in seconds to the nearest 0.5 second. A vehicle control and a standard of known potency are tested concurrently with screening candidates. If the activity of a test agent has not returned to baseline values at the 2-hour testing point, response latencies are determined at 4 and 6 hours. A final measurement is made at 24 hours if activity is still observed at the end of the test day. TEST USING CHEMICAL NOCICEPTIVE STIMULI Suppresion of Phenylbenzoquinone Irritant-Induced Writhing Groups of 5 Carworth Farms CF-1 mice are pretreated subcutaneously or orally with saline, morphine, codeine or the test compound. Twenty minutes (if treated subcutaneously) or fifty minutes (if treated orally) later, each group is treated with intraperitoneal injection of phenylbenzoquinone, an irritant known to produce abdominal contractions. The mice are observed for 5 minutes for the presence or absence of writhing starting 5 minutes after the injection of the irritant. MPE 50 's of the drug pretreatments in blocking writhing are ascertained. TESTS USING PRESSURE NOCICEPTIVE STIMULI EFFECT ON THE HAFFNER TAIL PINCH PROCEDURE A modification of the procedure of Haffner, Experimentelle Prufung Schmerzstillender. Mittel Deutch Med. Wschr., 55, 731-732 (1929) is used to ascertain the effects of the test compound on aggressive attacking responses elicited by a stimulus pinching the tail. Male albino rats (50-60 g) of the Charles River (Sprague-Dawley) CD-strain are used. Prior to drug treatment, and again at 0.5, 1, 2 and 3 hours after treatment, a Johns Hopkins 2.5-inch "bulldog" clamp is clamped onto the root of the rat's tail. The endpoint at each trial is clear attacking and biting behavior directed toward the offending stimulus, with the latency for attack reported in seconds. The clamp is removed in 30 seconds if attacking has not yet occurred, and the latency of response is recorded as 30 seconds. Morphine is active 17.8 mg/kg (i.p.). TESTS USING ELECTRICAL NOCICEPTIVE STIMULI THE "FLINCH-JUMP" TEST A modification of the flinch-jump procedure of Tenen, Psychopharmacologia, 12, 278-285 (1968) is used for determining pain thresholds. Male albino rats (175-200 g) of the Charles River (Sprague-Dawley) CD strain are used. Prior to receiving the drug, the feet of each rat are dipped into a 20% glycerol/saline solution. The animals are then placed in a chamber and presented with a series of 1-second shocks to the feet which are delivered in increasing intensity at 30-second intervals. These intensities are 0.26, 0.39, 0.52, 0.78, 1.05, 1.31, 1.58, 1.86, 2.13, 2.42, 2.72, and 3.04 mA. Each animal's behavior is rated for the presence of (a) flinch, (b) squeak and (c) jump or rapid forward movement at shock onset. Single upward series of shock intensities are presented to each rat just prior to, and at 0.5, 2, 4 and 24 hours subsequent to drug treatment. Results of the above tests are recorded as percent maximum possible effect (% MPE). The % MPE of each group is statistically compared to the % MPE of the standard and the predrug control values. The % MPE is calculated as follows: ##EQU1## As mentioned above, the compounds of the invention are especially useful as antiemetic and antinausea agents in mammals. They are particularly useful in preventing emesis and nausea induced by antineoplastic agents. The antiemetic properties of the compounds of formula (I) are determined in unanesthetized unrestrained cats according to the procedure described in Proc. Soc. Exptl. Biol. and Med., 160, 437-440 (1979). ANTAGONISM OF PGE 2 * DIARRHEA IN MICE The antidiarrheal activity of the invention compounds is determined by a modification of the method of Dajani et al., European Jour. Pharmacol., 34, 105-113 (1975). This method reliably elicits diarrhea in otherwise untreated mice within 15 minutes. Pretreated animals in which no diarrhea occurs are considered protected by the test agent. The constipating effects of test agents are measured as an "all or none" response, diarrhea being defined as watery unformed stools, very different from normal fecal matter, which consists of well-formed boluses, firm and relatively dry. Male albino mice of the Charles River CD-1 strain are used. They are kept in group cages and tested within one week following arrival. The weight range of the animals when tested is between 20-25 g. Pelleted rat chow is avilable ad libitum until 18 hours prior to testing, at which time food is withdrawn. Animals are weighed and marked for identification. Five animals are normally used in each drug treatment group. Mice weighing 20-25 g are housed in group cages, and fasted overnight prior to testing. Water is available ad libitum. Animals are challenged with PGE 2 (0.32 mg/kg i.p. in 5% ETOH) one hour after drug treatment, and immediately placed individually in transparent acrylic boxes of 15×15×18 cm. A disposable cardboard sheet on the bottom of the box is checked for diarrhea on an all or nothing basis at the end of 15 minutes. A vehicle +PGE 2 treatment group and a vehicle treatment group serve as controls in each day's testing. The data are analyzed using weighted linear regression of probit-response onlog dose, employing the maximum likelihood procedure. A computer program prints results in an analysis of linear regression format, including degrees of freedom, sum of squares, mean squares and critical values of F 05 and Chi square. If the regression is significant, the ED 30 , ED 50 , ED 70 , and ED 90 and then 95% confidence limits are calculated. The compounds of the present invention are active analgesics, antidiarrheals, antiemetics or antinauseants via oral and parenteral administration and are conveniently administered for these uses in composition form. Such compositions include a pharmaceutical carrier selected on the basis of the chosen route of administration and standard pharmaceutical practice. For example, they may be administered in the form of tablets, pills, powders or granules containing such excipients as starch, milk sugar, certain types of clay, etc. They may be administered in capsules, in admixtures with the same or equivalent excipients. They may also be administered in the form of oral suspensions, solutions, emulsions, syrups and elixirs which may contain flavoring and coloring agents. For oral administration of the therapeutic agents of this invention, tablets or capsules containing from about 0.01 to about 100 mg are suitable for most applications. Suspensions and solutions of these drugs, particularly those wherein R 1 is hydrogen, are generally prepared just prior to use in order to avoid problems of stability of the drug (e.g. oxidation) or of suspensions or solution (e.g. precipitation) of the drug upon storage. Compositions suitable for such are generally dry solid compositions which are reconstituted for injectable administration. The physician will determine the dosage which will be most suitable for an individual patient and it will vary with the age, weight and response of the particular patient and the route of administration. Generally, however, the initial analgesic dosage, as well as the initial dosage for prevention or treatment of nausea, in adults may range from 0.01 to 500 mg per day in single or divided doses. In many instances, it is not necessary to exceed 100 mg daily. The favored oral dosage range is from about 0.01 to about 300 mg/day; the preferred range is from about 0.10 to about 50 mg/day. The favored parenteral dose is from about 0.01 to about 100 mg/day; the preferred range from about 0.01 to about 20 mg/day. The invention is further illustrated by the following Examples. Abbreviations used in the Examples are: PMR, proton magnetic resonance; s, singlet; d, doublet; dd, double doublet; t, triplet; q, quartet; m, multiplet; Ar, aromatic; b, broad; IR, infrared spectrum; HRMS, high resolution mass spectrum; M + , molecular ion. EXAMPLE 1 N-Ethoxycarbonyl-2-[2-benzyloxy-4-(1,1-dimethylheptyl)phenyl]-4-piperidinone To 3.45 (0.142 mole) of magnesium is added a solution of 27.6 g (0.071 mole) of 2-benzyloxy-1-bromo-4-(1,1-dimethylheptyl)benzene in 71 ml of tetrahydrofuran, at such a rate that gentle reflux occurs. The Grignard solution is allowed to cool to 25° C. over 30 minutes, diluted with 71 ml of ether, the mixture cooled to -12° C. and 2.13 g (0.0112 mole) cuprous iodide is added followed by addition of 8.00 g (0.0473 mole) of N-ethoxycarbonyl-2,3-dihydro-4(1H)-pyridinone in 47 ml of ether over 20 minutes. The reaction is stirred 30 minutes longer at -12° C. and then added to 2 liters ether and 600 ml saturated ammonium chloride. The organic extract is washed with three 600 ml portions of saturated ammonium chloride, dried over magnesium sulfate and evaporated to an oil. This crude product is purified via column chromatography on 2 kg of silica gel eluting in 500 ml fractions with 50% ether-hexane to yield (fractions 17-24) 16.0 g (71%) of the title compound as an oil. PMR (CDCl 3 ) ppm (delta): 1.22 (s, gem CH 3 ), 2.47 (dd, J=7 and 5 Hz, CH 2 ), 2.91 (d, J=5 Hz, CH 2 ), 3.3-4.4 (m, CH 2 ), 4.09 (q, J=7 Hz, CH 2 ), 5.10 (s, OCH 2 ), 5.77 (t, J=6 Hz, CH), 6.8 (m, Ar, 2H), 7.10 (d, J=8 Hz, Ar, 1H), 7.39 (m, Ar, 5H). IR (CHCl 3 ) 1721, 1681, 1605, 1570 cm -1 . HRMS (m/e) 479.3278 (M + , Calcd. for C 30 H 41 NO 4 : 479.3025), 406, 388, 91. EXAMPLE 2 N-Ethoxycarbonyl-cis-2-[2-benzyloxy-4-(1,1-dimethylheptyl)phenyl]-4-piperidinol To a -50° C. solution of 12.1 g (25.1 mmol) of N-ethoxycarbonyl-2-[2-benzyloxy-4-(1,1-dimethylheptyl)phenyl]-4-piperidinone in 90 ml methanol and 90 ml of tetrahydrofuran is added 1.04 g (27.5 mmole) of sodium borohydride. The reaction is stirred 2 hours at -50° C. and then allowed to warm to 25° C. The reaction is quenched by addition to 300 ml saturated sodium chloride and the mixture extracted with ethyl ether (2 liters). The organic extract is washed with 300 ml saturated sodium chloride, dried over magnesium sulfate and the ether evaporated in vacuo. The crude product is purified via column chromatography on 2 kg silica gel eluting in 500 ml fractions with 2% methanol-5% ether-93% dichloromethane to yield (fractions 20-26) 6.04 g (50%) of the title compound as an oil and 3.75 g (31% of a mixture of the title compound and its trans-isomer. Further chromatography yields pure trans-isomer. Cis-Isomer PMR (CDCl 3 ), ppm (delta): 1.22 (s, gem CH 3 ), 3.2-4.2 (m, CH 2 , CH), 4.02 (q, J=7 Hz, CH 2 ), 5.07 (s, OCH 2 ), 5.35 (t, J=6 Hz, CH), 6.8 (m, Ar, 2H), 7.06 (d, J=8 Hz, Ar, 1H), 7.35 (m, Ar, 5H). IR (CHCl 3 ) 3559, 3443, 1672, 1610, 1572 cm -1 . HRMS (m/e) 481.3154 (M + , Calcd. for C 30 H 43 NO 4 : 481.3181), 408, 390, 91. Trans-Isomer PMR (CDCl 3 ) ppm (delta): 1.22 (s, gem CH 3 ), 2.55 (m), 3.0-4.3 (m), 4.02 (q, J=7 Hz, CH 2 ), 5.08 (s, OCH 2 ), 5.68 (bd, J=6 Hz, 1H), 6.8 (m, Ar, 3H), 7.35 (m, Ar, 5H). HRMS (m/e) 481.3275 (M + , Calcd. for C 30 H 43 NO 4 : 481.3181), 463, 408, 390, 91. EXAMPLE 3 Cis-2-[2-benzyloxy-4-(1,1-dimethylheptyl)phenyl]-4-piperidinol To a solution of 4.62 g (9.59 mmole) of N-ethoxycarbonyl-cis-2-[2-benzyloxy-4-(1,1-dimethylheptyl)phenyl]-4-piperidinol in 5 ml ethanol is added a solution of 4.2 g (75 mmole) of potassium hydroxide in 25 ml ethylene glycol and 4.2 ml water. The resultant mixture is evaporated at reduced pressure to remove ethanol and is then heated to reflux (bath 185° C.). After 24 hours material boiling at 80°-100° C. is removed by distillation, 6 ml ethylene glycol is added and the reaction continued at reflux for 17 hours. After cooling, the mixture is added to 500 ml dichloromethane and 80 ml water. The organic extract is washed with 80 ml saturated sodium chloride, dried over magnesium sulfate and evaporated in vacuo. The resulting crude oil is purified via column chromatography on 300 g of silica gel eluting in 20 ml fractions with 2.5% triethylamine, 2.5% methanol, 95% ethyl ether (fractions 1-109) and 5% triethylamine, 5% methanol, 90% ethyl ether (fractions 110-200). Fractions 138-190 gave 3.13 g (83%) of the title compound. PMR (CDCl 3 ) ppm (delta): 1.22 (s, gem CH 3 ), 3.8 (m, 1H), 4.0 (m, 1H), 5.05 (s, OCH 2 ), 6.9 (m, Ar, 2H), 7.35 (m, Ar, 6H). IR (CHCl 3 ) 3546, 3279, 1608, 1621 cm -1 . HRMS (m/e) 409.2886 (M + , Calcd. for C 27 H 39 NO 2 : 409.2971), 392, 364, 318, 135, 91. EXAMPLE 4 N-Ethoxycarbonyl-2-[4-(1,1-dimethylheptyl)-2-hydroxyphenyl]-4-piperidinone A mixture of 369 mg (0.77 mmole) of N-ethoxycarbonyl-2-[2-benzyloxy-4-(1,1-dimethylheptyl)phenyl]-4-piperidinone and 414 mg of 5% palladium on carbon (50% wet) in 5 ml ethanol was stirred under 1 atmosphere of hydrogen at 25° C. until the hydrogen uptake is complete (approximately 3 hours). The reaction is filtered through a filter aid, washing with ethanol and the filtrate evaporated in vacuo. The residual crude oil is purified via column chromatography on 22 g of silica gel eluting in 4 ml fractions with 15% ethyl ether in dichloromethane to yield (fractions 28-42) 174 mg (57%) of the title compound as an oil. PMR (CDCl 3 ) ppm (delta): 0.83 (m, CH 3 ), 1.25 (s, gem --CH 3 ), 3.7-4.4 (m), 5.45 (m, 1H), 6.7-7.2 (m, Ar, 3H). IR (CHCl 3 ) 3559, 3333, 1678, 1623, 1575 cm -1 . HRMS (m/e) 389.2544 (M + , Calcd. for C 23 H 35 NO 4 : 389.2557), 316, 304, 300, 273, 258, 161, 142. EXAMPLE 5 N-Methyl-cis-2-[2-benzyloxy-4-(1,1-dimethylheptyl)phenyl]-4-piperidinol To a 25° C. slurry of 267 mg (7.04 mmole) of lithium aluminum hydride in 12 ml ethyl ether is added dropwise over 30 minutes a solution of 1.50 g (3.11 mmole) of N-ethoxycarbonyl-cis-2-[2-benzyloxy-4-(1,1-dimethylheptyl)phenyl]-4-piperidinol. The reaction is stirred for 0.5 hour at 25° C., then two hours at reflux. The reaction is quenched by addition of wet magnesium sulfate followed by decantation and washing of the salts with two 30 ml portions of ether. The ether extract is washed with 10 ml saturated sodium chloride, dried over magnesium sulfate and evaporated to give 1.19 g (91%) of the title compound as a solid. PMR (CDCl 3 ) ppm (delta): 0.82 (m, CH 3 ), 1.24 (s, gem --CH 3 ), 2.00 (s, N--CH 3 ), 3.0 (m, 1H), 3.4-4.0 (m, 2H), 5.04 (s, OCH 2 ), 6.9 (m, Ar, 2H), 7.35 (m, Ar, 6H). IR (CHCl 3 ) 3571, 3378, 1613, 1575 cm -1 . HRMS (m/e) 423.3100 (M + , Cacld. for C 28 H 41 NO 2 : 423.3127), 408, 332, 314, 300, 246, 91. EXAMPLE 6 N-Methyl-cis-2-[4-(1,1-dimethylheptyl)-2-hydroxyphenyl]-4-piperidinol Using the procedure of Example 4, 1.13 g (2.68 mmole) of N-methyl-cis-2-[2-benzyloxy-4-(1,1-dimethylheptyl)phenyl]-4-piperidinol and 452 mg of 5% palladium on carbon (50% wet) affords 0.752 g (84%) of the title compound as an oil. PMR (CDCl 3 ) ppm (delta): 0.80 (m, CH 3 ), 1.22 (s, gem CH 3 ), 2.16 (s, NCH 3 ), 2.9-4.0 (m), 6.7 (m, Ar, 3H). IR (CHCl 3 ) 3571, 3425, 1623, 1572, 1502 cm -1 . HRMS (m/e) 333.2650 (M + , Calcd. for C 21 H 35 NO 2 : 333.2659), 318, 316, 249, 114. EXAMPLE 7 A. N-Ethoxycarbonyl-cis-2-[4-(1,1-dimethylheptyl)-2-hydroxyphenyl]-4-piperidinol Using the procedure of Example 4, 423 mg (0.878 mmole) of N-ethoxycarbonyl-cis-2-[2-benzyloxy-4-(1,1-dimethylheptyl)phenyl]-4-piperidinol and 210 mg of 5% palladium on carbon (50% wet) provides 265 mg (77%) of the title compound as an oil. PMR (CDCl 3 ) ppm (delta): 0.82 (m, CH 3 ), 1.22 (s, gem CH 3 ), 3.0-4.2 (m), 4.04 (q, J=7 Hz, CH 2 ), 5.26 (t, J=6 Hz, CH), 6.75 (m, Ar, 2H), 7.51 (d, J=8 Hz, Ar, H). IR (CHCl 3 ) 3684, 3589, 3216, 1649, 1564 cm -1 . HRMS (m/e) 391.2699 (M + , Calcd. for C 23 H 37 NO 4 : 391.2713), 318, 306, 300, 161. B. Cis-2-[4-(1,1-dimethylheptyl)-2-hydroxyphenyl]-4-piperidinol Similarly, 758 mg (1.85 mmol) of cis-2-[2-benzyloxy-4-(1,1-dimetylheptyl)phenyl]-4-piperidinol and 303 mg of 5% palladium-on-carbon (50% wet) yields 403 mg (68%) of the title compound, M.P. 97°-102° (dichloromethane-pentane). PMR (CDCl 3 ) ppm (delta): 0.80 (m, CH 3 ), 1.22 (s, gem --CH 3 ), 1.22-4.8 (m), 6.8 (m, Ar, 3H). IR (CHCl 3 ) 3559, 3378, 3279, 1623, 1570, 1493 cm -1 . HRMS (m/e) 319.2465 (M + , Calcd. for C 20 H 33 NO 2 : 319.2503), 302, 274, 163, 161, 148, 100. EXAMPLE 8 N-Propionyl-cis-2-[2-benzyloxy-4-(1,1-dimethylheptyl)phenyl]-4-propionylpiperidine To a 25° C. solution of 689 mg (1.68 mmole) cis-2-[2-benzyloxy-4-(1,1-dimethylheptyl)phenyl]-4-piperidinol and 1.02 g (8.36 mmole) 4-N,N-dimethylaminopyridine in 2.6 ml dichloromethane is added, at once, 0.64 ml (5.0 mmole) of propionic anhydride. The reaction is stirred 3 hours and then added to a mixture of 20 ml 1N hydrochloric acid and 100 ml ethyl ether. The organic layer is washed with 15 ml 1N hydrochloric acid, 25 ml saturated sodium bicarbonate, 20 ml saturated sodium chloride, dried over magnesium sulfate and the solvent is evaporated to afford an oil. The crude product is purified via column chromatography on 50 g of silica gel eluting in 10 ml fractions with 20% hexane in ethyl ether to give 768 mg (88%) of the title compound as an oil. PMR (CDCl 3 ) ppm (delta): 0.62-1.3 (m, all CH 3 ), 4.5 (m, 1H), 5.05 (s, OCH 2 ), 5.37 (m, 1H), 6.8 (m, Ar, 2H), 7.00 (d, J=8 Hz, Ar, H), 7.35 (q, Ar, 5H). IR (CHCl 3 ) 1736, 1639, 1575 cm -1 . EXAMPLE 9 N-Propyl-cis-2-[4-(1,1-dimethylheptyl)-2-hydroxyphenyl]-4-piperidinol A. N-Propyl-cis-2-[2-benzyloxy-4-(1,1-dimethylheptyl)phenyl]-4-piperidinol Using the procedure of Example 5, 723 mg (1.46 mmole) of N-propionyl-cis-2-[2-benzyloxy-4-(1,1-dimethylheptyl)phenyl]-4-propionyloxypiperidine and 129 mg (3.40 mmole) of lithium aluminum hydride gives 582 mg (88%) of the title compound as an oil. PMR (CDCl 3 ) ppm (delta): 0.6-1.22 (m, all CH 3 ), 2.9-4.0 (m, 4H), 5.04 (s, OCH 2 ), 6.85 (m, Ar, 2H), 7.35 (m, Ar, 6H). IR (CHCl 3 ) 3571, 3390, 1613, 1575 cm -1 . HRMS (m/e) 451.3449 (M + , Calcd. for C 30 H 45 NO 2 : 451.3439), 422, 404, 91. B. Employing the procedure of Example 4, 535 mg (1.18 mmole) N-propyl-cis-2-[2-benzyloxy-4-(1,1-dimethylheptyl)phenyl]-4-piperidinol and 212 mg 5% palladium on carbon (50% wet) gives 402 mg (94%) of the title compound as an oil. PMR (CDCl 3 ) ppm (delta): 0.65-1.25 (m, all CH 3 ), 3.0-4.0 (m, 3H), 6.75 (s, Ar, 3H). IR (CHCl 3 ) 3521, 3367, 1613, 1565 cm -1 . HRMS (m/e) 361.2963 (M + , Calcd. for C 23 H 39 NO 2 : 361.2971), 332, 314, 271. EXAMPLE 10 N-(2-Propenyl)-cis-2-[2-benzyloxy-4-(1,1-dimethylheptyl)phenyl]-4-piperidinol A mixture of 778 mg (1.90 mmole) of cis-2-[2-benzyloxy-4-(1,1-dimethylheptyl)phenyl]-4-piperidinol, 160 microliters (1.84 mmole) of 1-bromo-2-propene and 300 mg (2.17 mmole) of potassium carbonate in 10 ml ethanol is stirred at 25° C. for 20.5 hours. An additional 4 microliters of 1-bromo-2-propene is added to the reaction and stirring continued for 7 hours. The reaction mixture is then added to 50 ml saturated sodium chloride and extracted with 250 ml ethyl ether. The ether extract is dried over magnesium sulfate and the solvent is evaporated. The resulting oil is purified via column chromatography on 28 g of silica gel eluted in 7 ml fractions with 1:3 methanol/ethyl ether to yield (fractions 10-35) 518 mg (61%) of the title compound as an oil. PMR (CDCl 3 ) ppm (delta): (m, CH 3 ), 1.22 (s, gem --CH 3 ), 3.0-4.0 (m, 5H), 4.8-5.2 (m, vinyl 2H), 5.02 (s, OCH 2 ), 5.3-6.2 (m, vinyl H), 6.9 (m, Ar, 2H), 7.35 (m, Ar, 6H). IR (CHCl 3 ) 3584, 3436, 1675, 1647, 1618, 1580 cm -1 . HRMS (m/e) 449.3199 (M + , Calcd. for C 30 H 43 NO 2 : 449.3283), 432, 408, 390, 358, 340, 328, 140, 91. EXAMPLE 11 N-(2-Propenyl)-cis-2-[4-(1,1-dimethylheptyl)-2-hydroxyphenyl]-4-piperidinol A solution of 6.8 ml (74.6 mmole) of propanethiol in 75 ml of tetrahydrofuran is degassed by three freeze-thaw cycles at 0.1 torr. The resultant solution is cooled to -78° C. and 28 ml of 2.5M n-butyllithium in hexane is added. The reaction is then allowed to warm to 25° C. and stirred 3 hours longer. The reaction is evaporated to dryness under high vacuum and the residue dissolved in 70 ml of degassed hexamethylphosphoramide. To a 25° C. degassed solution of 218 mg (0.486 mmole) of N-(2-propenyl)-cis-2-[2-benzyloxy-4-(1,1-dimethylheptyl)phenyl]-4-piperidinol in 1 ml of hexamethylphosphoramide is added 2.2 ml of the above prepared solution of lithium propanethiolate. The reaction is stirred 30 minutes at 25° C. and 1.5 hour at 105° C. followed by cooling to 25° C. The reaction is quenched by addition to 30 ml water and the mixture extracted with 150 ml ethyl ether. The ether extract is washed twice with 30 ml water, once with 30 ml saturated sodium chloride, dried over magnesium sulfate and evaporated to an oil. The crude product is purified via column chromatography on 48 g of silica gel eluting in 8 ml fractions with ethyl ether to give (fractions 12-24) 101 mg (58%) of the title compound as an oil. PMR (CDCl 3 ) ppm (delta): 0.80 (m, CH 3 ), 1.24 (s, gem --CH 3 ), 2.9-4.2 (m, 5H), 5.15 (m, vinyl 2H), 5.4-6.3 (m, vinyl H), 6.85 (m, Ar, 3H). IR (CHCl 3 ) 3546, 3390, 1618, 1572, 1495 cm -1 . HRMS (m/e) 359.2830 (M + , Calcd. for C 23 H 37 NO 2 : 359.2815), 318, 300, 275, 140. EXAMPLE 12 N-Methoxycarbonyl-cis-2-[4-(1,1-dimethylheptyl)-2-hydroxyphenyl]-4-piperidinol A. N-Methoxycarbonyl-cis-2-[2-benzyloxy-4-(1,1-dimethylheptyl)phenyl]-4-piperidinol To a 0° C. solution of 193 mg (0.471 mmole) of cis-2-[2-benzyloxy-4-(1,1-dimethylheptyl)phenyl]-4-piperidinol and 0.29 ml triethylamine in 2.2 ml tetrahydrofuran is added dropwise 40 microliters (0.518 mmole) of methyl chloroformate. The reaction is stirred 40 minutes and then another 10 microliters of methyl chloroformate is added. The reaction is stirred 40 minutes longer, diluted with ether and filtered. The filtrate is washed with saturated sodium bicarbonate and saturated sodium chloride, dried over magnesium sulfate and evaporated to an oil. The crude product is purified via column chromatography on 10.4 g of silica gel eluting in 3 ml fractions with 1:3 ethyl ether/hexane to yield (fractions 16-30) 198 mg (80%) of the title compound as an oil. PMR (CDCl 3 ) ppm (delta): 0.82 (m, CH 3 ), 1.20 (s, gem CH 3 ), 3.57 (s, OCH 3 ), 4.1 (m, CH), 5.02 (s, OCH 2 ), 5.33 (bt, J=6 Hz, CH), 6.85 (m, Ar, 2H), 7.00 (d, J=8 Hz, Ar, H), 7.27 (s, Ar, 5H). IR (CHCl 3 ) 3521, 3390, 1681, 1597, 1570, 1490 cm -1 . HRMS (m/e) 467.3070 (M + , Calcd. for C 29 H 41 NO 4 : 467.3025), 449, 409, 408, 376, 158, 91. B. Debenzylation of 177 mg (0.377 mmole) of N-methoxycarbonyl cis-2-[2-benzyloxy-4-(1,1-dimethylheptyl)phenyl]-4-piperidinol with 144 mg of 5% palladium on carbon (50% wet) by the procedure of Example 4 affords 81.3 mg (57%) of the title compound as an oil, 4.1 mg (3%) of by-product 5-(1,1-dimethylheptyl)-2-[3-hydroxy-5-(N-methoxycarbonylamino)pentyl]phenol as an oil, and 49.2 mg (35%) of a mixture of the two. Title Compound PMR (CDCl 3 ) ppm (delta): 0.8 (m, CH 3 ), 1.22 (s, gem --CH 3 ), 3.66 (s, OCH 3 ), 4.15 (m, CH), 5.36 (bt, J=7 Hz, CH), 6.8 (m, Ar, 2H), 7.55 (d, J=8 Hz, Ar, H). IR (CHCl 3 ) 3534, 3145, 1647, 1616, 1560 cm -1 . HRMS (m/e) 377.2565 (M + , Calcd. for C 22 H 35 NO 4 : 377.2557), 318, 292, 260, 161. By-Product HRMS (m/e) 379.2699 (M + , Calcd. for C 22 H 37 O 4 : 379.2713), 361, 347, 318, 147. EXAMPLE 13 N-Methylsulfonyl-cis-2-[4-(1,1-dimethylheptyl)-2-hydroxyphenyl]-4-piperidinol A. N-Methylsulfonyl-cis-2-[2-benzyloxy-4-(1,1-dimethylheptyl)phenyl]-4-piperidinol Reacting 409 mg (0.997 mmol) of cis-2-[2-benzyloxy-4-(1,1-dimethylheptyl)phenyl]-4-piperidinol and 81 microliters (1.05 mmole) of methanesulfonyl chloride by the procedure of Example 12, Part A, gives 130 mg (27%) of the mesylate as an oil. PMR (CDCl 3 ) ppm (delta): 0.82 (m, CH 3 ), 1.22 (s, gem --CH 3 ), 2.51 (s, SCH 3 ), 5.07 (s, OCH 2 ), 6.9 (m, Ar, 2H), 7.31 (m, Ar, 6H). IR (CHCl 3 ) 3509, 3378, 1751, 1605, 1567, 1488. HRMS (m/e) 487.2696 (M + , Calcd. for C 28 H 41 NO 4 S: 487.2746), 408, 402, 390, 91. B. Hydrogenolysis of 121 mg (0.248 mmol) of N-methylsulfonyl-cis-2-[2-benzyloxy-4-(1,1-dimethylheptyl)phenyl]-4-piperidinol with 110 mg of 5% palladium on carbon (50% wet) by the procedure of Example 4 gives 85.3 mg (86%) of the title compound as an oil. PMR (CDCl 3 ) ppm (delta): 0.8 (m, CH 3 ), 1.22 (s, gem --CH 3 ), 2.46 (s, SCH 3 ), 4.67 (t, J=7 Hz, CH), 6.85 (m, Ar, 2H), 7.22 (d, J=8 Hz, Ar, H). IR (CHCl 3 ) 3534, 3344, 1613, 1563, 1493 cm -1 . HRMS (m/e) 397.2253 (M + , Calcd. for C 21 H 35 NO 4 S: 397.2313), 318, 312, 300, 294, 161. EXAMPLE 14 N-(3-Hydroxypropionyl)-cis-2-[4-(1,1-dimethylheptyl)-2-hydroxyphenyl]-4-piperidinol A. N-(3-Benzyloxy)propionyl-cis-2-[2-benzyloxy-4-(1,1-dimethylheptyl)phenyl]-4-piperidinol To a solution of 789 mg (1.93 mmole) of cis-2-[2-benzyloxy-4-(1,1-dimethylheptyl)phenyl]-4-piperidinol and 347 mg (1.93 mmole) of 3-benzyloxypropionic acid in 2.5 ml of dichloromethane is added 403 mg (1.95 mmole) of dicyclohexylcarbodiimide. The reaction is stirred for 3.5 hours and then an additional 42.9 mg of dicyclohexylcarbodiimide is added. The reaction is stirred 18 hours longer and then filtered. The filtrate is washed with 1N hydrochloric acid, saturated sodium bicarbonate solution, dried over magnesium sulfate and evaporated to an oil. This crude product is purified via column chromatography on 78 g of silica gel, eluting in 16 ml fractions with 1:3 ethyl ether/hexane to give 712 mg (65%) of the desired amide as an oil which is used in the next step. PMR (CDCl 3 ) ppm (delta): 0.82 (m, CH 3 ), 1.20 (s, gem CH 3 ), 4.47 (s, OCH 2 ), 5.08 (s, OCH 2 ), 5.4 (m, 1H), 6.95 (m, Ar, H), 7.23 (s, Ar, 5H), 7.36 (s, Ar, 5H). IR (CHCl 3 ) 3623, 3460, 1626, 1572, 1481 cm -1 . HRMS (m/e) 571.3584 (M + , Calcd. for C 37 H 49 NO 4 : 571.3649), 480, 408, 318, 91. B. Hydrogenolysis of 710 mg (1.24 mmole) of N-(3-benzyloxypropionyl)-cis-2-[2-benzyloxy-4-(1,1-dimethylheptyl)phenyl]-4-piperidinol with 700 mg of 5% palladium on carbon (50% wet) by the method of Example 4 yields 429 mg (88%) of the title compound. M.P. 119°-121° C. PMR (CDCl 3 ) ppm (delta): 0.82 (m, CH 3 ), 1.22 (s, gem CH 3 ), 3.3-4.3 (m), 5.59 (t, J=7 Hz, CH), 6.8 (m, Ar, 2H), 7.57 (d, J=8 Hz, Ar, H). IR (CHCl 3 ) 3571, 3125, 1587 cm -1 . HRMS (m/e) 391.2716 (M + , Calcd. for C 23 H 37 NO 4 : 391.2713), 374, 319, 318, 302, 161. Analysis: Calcd. for C 23 H 37 NO 4 : C, 70.55; H, 9.53; N, 3.58. Found: C, 70.66; H, 9.19; N, 3.61. EXAMPLE 15 N-Butyryl-cis-2-[4-(1,1-dimethylheptyl)-2-hydroxyphenyl]-4-piperidinol A. N-Butyryl-cis-2-[2-benzyloxy-4-(1,1-dimethylheptyl)phenyl]-4-piperidinol Acylation of 421 mg (1.03 mmole) of cis-2-[2-benzyloxy-4-(1,1-dimethylheptyl)phenyl]-4-piperidinol with 110 mg (1.03 mmol) of butyryl chloride by the procedure of Example 12, Part A, gives 530 mg (96%) of the desired amide as an oil. PMR (CDCl 3 ) ppm (delta): 0.8-1.2 (m, all CH 3 ), 5.10 (s, OCH 2 ), 5.35 (m, CH), 6.85 (m, Ar, 2H), 7.04 (d, J=8 Hz, Ar, H), 7.35 (s, Ar, 5H). IR (CHCl 3 ) 3655, 3587, 3451, 1627, 1572 cm -1 . HRMS (m/e) 479.3418 (M + , Calcd. for C 31 H 45 NO 3 : 479.3388), 408, 388, 372, 318, 300, 100, 91. B. Debenzylation of 529 mg (1.10 mmol) of the product of Part A, above with 301 mg of 5% palladium on carbon (50% wet) by the method of Example 4 affords 334 mg (78%) of the title compound as an oil. PMR (CDCl 3 ) ppm (delta): 0.7-1.2 (m, all CH 3 ), 3.55 (m, CH 2 ), 4.05 (m, CH), 5.61 (t, J=7 Hz, CH), 6.8 (m, Ar, 2H), 7.62 (d, J=8 Hz, Ar, H). IR (CHCl 3 ) 3686, 3591, 3448, 1548, 1499 cm -1 . HRMS (m/e) 389.2903 (M + , Calcd. for C 24 H 39 NO 3 : 389.2920), 372, 318, 302, 284, 274, 257, 234, 217, 161, 100. Employing the appropriate acid chloride in place of butyryl chloride in the procedure of Part A, above and debenzylation by the method of Part B similarly provides the following amides: ______________________________________ ##STR12## Yield,R.sub.1 R.sub.2 % Physical Data______________________________________benzyl acetyl 99 PMR (CDCl.sub.3) ppm (delta): 0.8 (m, CH.sub.3), 1.22 (s, gem CH.sub.3), 1.91 (s, CH.sub.3), 5.08 (s, OCH.sub.2), 5.27 (m, CH), 6.82 (m, Ar, 2H), 7.03 (d, J = 8 Hz, Ar, H), 7.35 (s, Ar, 5H). IR (CHCl.sub.3) 3587, 3420, 1630, 1573, 1495 cm.sup.-1. HRMS (m/e) 451.3089 (M.sup.+, Calcd. for C.sub.29 H.sub.41 NO.sub.3 : 451.3076), 408, 360, 344, 318, 300, 91.H acetyl 91 PMR (CDCl.sub.3) ppm (delta); 0.8 (m, CH.sub.3), 1.22 (s, gem CH.sub.3), 2.08 (s, CH.sub.3), 3.55 (m, 2H), 4.08 (m, CH), 5.57 (t, J = 7 Hz, CH), 6.81 (m, Ar, 2H), 7.63 (d, J = 8 Hz, Ar, H). IR (CHCl.sub.3) 3598, 3405, 1603, 1499 cm.sup.-1. HRMS (m/e) 361.2596 (M.sup.+ Calcd. for C.sub.22 H.sub.35 NO.sub.3 : 361.2608), 344, 318, 302, 234, 217, 199, 162, 161.benzyl propionyl 100 PMR (CDCl.sub.3) ppm (delta): 1.20 (s, gem CH.sub.3), 5.06 (s, OCH.sub.2), 5.29 (m, CH), 6.78 (m, Ar, 2H), 6.98 (d, J = 8 Hz, Ar, H), 7.30 (m, Ar, 5H). IR (CHCl.sub.3) 3591, 3444, 1630, 1572, 1496 cm.sup.-1. HRMS (m/e) 465.2646 (M.sup.+, Calcd. for C.sub.30 H.sub.43 NO.sub.3 : 465.3232), 408, 318, 91.H propionyl 91 PMR (CDCl.sub.3) ppm (delta): 1.22 (s, gem CH.sub.3), 3.53 (m, 2H), 4.1 (m, CH), 5.63 (bt, J = 7 Hz, CH), 6.82 (m, Ar, 2H), 7.63 (d, J = 8 Hz, Ar, H). IR (CHCl.sub.3) 3595, 3400, 1601, 1499 cm.sup.-1. HRMS (m/e) 375.2711 (M.sup.+, Calcd. for C.sub.23 H.sub.37 NO.sub.3 : 375.2764), 358, 346, 318, 302, 300, 284, 234, 217, 199.benzyl n-pentanoyl 99 PMR (CDCl.sub.3) ppm (delta): 0.8-1.2 (m, all CH.sub.3), 5.10 (s, OCH.sub.2), 5.30 (bt, J = 6 Hz, CH), 6.87 (m, Ar, 2H), 7.02 (d, J = 8 Hz, Ar, H), 7.36 (m, Ar, 5H). IR (CHCl.sub.3) 3593, 3457, 1629, 1573, 1495 cm.sup.-1. HRMS (m/e) 493.3224 (M.sup.+, Calcd. for C.sub.32 H.sub.47 NO.sub.3 : 493.3544), 408, 402, 386, 318, 91.H n-pentanoyl 47 PMR (CDCl.sub.3) ppm (delta): 1.22 (s, gem CH.sub.3), 3.55 (m, 2H), 4.15 (m, CH), 5.60 (bt, J = 6 Hz, CH), 6.79 (m, Ar, 2H), 7.60 (d, J = 8 Hz, Ar, H). IR (CHCl.sub.3) 3595, 3420, 1598, 1499 cm.sup.-1. HRMS (m/e) 403.3072 (M.sup.+, Calcd. for C.sub.25 H.sub.41 NO.sub.3 : 403.3076), 387, 324.______________________________________ EXAMPLE 16 N-(3-Hydroxypropyl)-cis-2-[4-(1,1-dimethylheptyl)-2-hydroxyphenyl]-4-piperidinol Reduction of 593 mg (1.51 mmole) of N-(3-hydroxypropionyl)-cis-2-[4-(1,1-dimethylheptyl)-2-hydroxyphenyl]-4-piperidinol with 152 mg (4.01 mmole) of lithium aluminum hydride by the procedure of Example 5 provides 398 mg (70%) of the title compound as an oil. PMR (CDCl 3 ) ppm (delta): 1.24 (s, gem --CH 3 ), 3.0-4.6 (m), 6.75 (s, Ar, 3H). IR (CHCl 3 ) 3592, 3462, 1622, 1605, 1573 cm -1 . HRMS (m/e) 377.2933 (M + , Calcd. for C 23 H 39 NO 3 : 377.2920), 332, 314, 271, 161, 158, 88. EXAMPLE 17 N-Formyl-cis-2-[4-(1,1-dimethylheptyl)-2-hydroxyphenyl]-4-piperidinol A. N-Formyl-cis-2-[2-benzyloxy-4-(1,1-dimethylheptyl)phenyl]-4-piperidinol Using the procedure of Example 14, Part A, 1.81 g (4.42 mmole) of cis-2-[2-benzyloxy-4-(1,1-dimethylheptyl)phenyl]-4-piperidinol, 206 mg (4.48 mmole) of formic acid and 1.04 g (5.04 mmole) of dicyclohexylcarbodiimide gives 1.32 g (70%) of the corresponding formamide. M.P. 119.5°-122.5° C. (recrystallized from methanol). PMR (CDCl 3 ) ppm (delta): 0.82 (m, CH 3 ), 1.23 (s, gem --CH 3 ), 5.02 (s, OCH 2 ), 6.88 (m, Ar, 2H), 7.25 (m, Ar, 6H), 7.58 (s, CHO). IR (CHCl 3 ) 3687, 3586, 3426, 1648, 1611, 1571, 1494 cm -1 . HRMS (m/e) 437.2935 (M + , Calcd. for C 28 H 39 NO 3 : 437.2920), 408, 347, 91. B. Debenzylation of 1.31 g (2.99 mmol) of the product of Part A with 830 mg of 5% palladium on carbon (50% wet) gives 752 mg (72%) of the title compound. M.P. 149°-150° C. (recrystallized from methanol-water). PMR (CDCl 3 ) ppm (delta): 0.80 (m, CH 3 ), 1.25 (s, gem --CH 3 ), 6.75 (m, Ar, 2H), 7.10 (d, J=8 Hz, Ar, H), 7.49 (s, CHO). IR (CHCl 3 ) 3593, 3250, 1644, 1585 cm -1 . HRMS (m/e) 347.2415 (M + , Calcd. for C 21 H 33 NO 3 : 347.2452), 346, 330, 262, 161. Analysis: Calcd. for C 21 H 33 NO 3 : C, 72.60; H, 9.57; N, 4.03. Found: C, 73.38; H, 9.24; N, 3.95. EXAMPLE 18 N-Propioloyl-cis-2-[4-(1,1-dimethylheptyl)-2-hydroxyphenyl]-4-piperidinol Repeating the procedure of Example 10, but with 760 mg (2.38 mmole) of cis-2-[4-(1,1-dimethylheptyl)-2-hydroxyphenyl]-4-piperidinol, 970 mg (11 mmole) of propynoyl chloride and 2.07 g (15 mmole) of potassium carbonate in 70 ml of tetrahydrofuran yields 430 mg (38%) of the title compound as an oil. PMR (CDCl 3 ) ppm (delta): 0.82 (m, CH 3 ), 1.22 (s, gem --CH 3 ), 3.11 (s, CH), 5.65 (bt, J=6 Hz, CH), 6.80 (m, Ar, 2H), 7.60 (d, J=8 Hz, Ar, H). IR (CHCl 3 ) 3595, 3296, 3200, 2110, 1621, 1602, 1500 cm -1 . HRMS (m/e) 371.2495 (M + , Calcd. for C 23 H 33 NO 3 : 371.2452), 354, 287, 286, 233, 199, 187, 161. EXAMPLE 19 N-(2-Propynyl)-cis-2-[4-(1,1-dimethylheptyl)-2-hydroxyphenyl]-4-piperidinol Employing the procedure of Example 10 with 321 mg (1.01 mmole) of cis-2-[4-(1,1-dimethylheptyl)-2-hydroxyphenyl]-4-piperidinol, 82 microliter (1.06 mmole) or propynyl bromide and 292 mg (2.12 mmole) of potassium carbonate affords 205 mg (57%) of the title compound as an oil. PMR (CDCl 3 ) ppm (delta): 0.82 (m, CH 3 ), 1.25 (s, gem --CH 3 ), B 2.22 (t, J=2 Hz, .tbd.CH), 3.35 (d, J=2 Hz, 2H), 6.78 (Ar, 3H). IR (CHCl 3 ) 3595, 3303, 1627, 1576, 1502 cm -1 . HRMS (m/e) 357.2682 (M + , Calcd. for C 23 H 35 NO 2 : 357.2659), 340, 318, 233, 138. EXAMPLE 20 N-Ethoxycarbonyl-2-[2-benzyloxy-4-(5-phenyl-2-pentyloxy)phenyl]-4-piperidon Repeating the procedure of Example 1 but preparing the Grignard reagent with 2-benzyloxy-4-(5-phenyl-2-pentyloxy)bromobenzene, affords the title compound in like manner. EXAMPLE 21 Similarly, the following products are prepared by the procedure of Example 1 ##STR13## where Z and W are as defined below. ______________________________________ Z W______________________________________C(CH.sub.3).sub.2 (CH.sub.2).sub.2 HC(CH.sub.3).sub.2 (CH.sub.2).sub.10 HC(CH.sub.3).sub.2 (CH.sub.2).sub.4 C.sub.6 H.sub.5C(CH.sub.3).sub.2 (CH.sub.2).sub.4 4-pyridylC(CH.sub.3).sub.2 (CH.sub.2).sub.3 2-pyridylC(CH.sub.3).sub.2 (CH.sub.2).sub.10 C.sub.6 H.sub.5CH(CH.sub.3)(CH.sub.2).sub.2 C.sub.6 H.sub.5CH(C.sub.2 H.sub.5)(CH.sub.2).sub.2 4-ClC.sub.6 H.sub.5CH(C.sub.2 H.sub.5)(CH.sub.2).sub.4 4-FC.sub.6 H.sub.4(CH.sub.2).sub.5 HCH.sub. 2 C.sub.6 H.sub.5(CH.sub.2).sub.11 H(CH.sub.2).sub.13 H(CH.sub.2).sub.4 C.sub.6 H.sub.5(CH.sub.2).sub.8 HO(CH.sub.2).sub.4 4-FC.sub.6 H.sub.4O(CH.sub.2).sub.8 C.sub.6 H.sub.5O(CH.sub.2).sub.10 4-ClC.sub.6 H.sub.4OCH(CH.sub.3)(CH.sub.2).sub.8 C.sub.6 H.sub.5OCH(CH.sub.3)CH.sub.2 4-FC.sub.6 H.sub.4OCH(CH.sub.3)(CH.sub.2).sub.3 C.sub.6 H.sub.5OCH.sub.2 CH(CH.sub.3 )CH.sub.2 C.sub.6 H.sub.5OCH(CH.sub.3)(CH.sub.2).sub.10 HOC(CH.sub.3).sub.2 (CH.sub.2).sub.5 HOC(CH.sub.3).sub.2 (CH.sub.2).sub.7 HO(CH.sub.2).sub.13 HO(CH.sub.2).sub.13 C.sub.6 H.sub.5OCH(CH.sub.3)(CH.sub.2).sub.6 4-FC.sub.6 H.sub.4OC(CH.sub.3).sub.2 (CH.sub.2).sub.10 4-FC.sub.6 H.sub.4O(CH.sub.2).sub.12 C.sub.6 H.sub.5O(CH.sub.2).sub.6 C.sub.6 H.sub.5O(CH.sub.2).sub.2 4-pyridylOCH(CH.sub.3)(CH.sub.2).sub.3 2-pyridylO(CH.sub.2).sub.5 3-pyridylO(CH.sub.2).sub.10 2-pyridylOCH(C.sub.2 H.sub.5)(CH.sub.2).sub.2 4-pyridyl______________________________________ EXAMPLE 22 In like manner the following congeners are prepared by the procedure of Example 1 from the appropriate N-substituted-2,3-dihydro-4(1H)pyridinone and 2-benzyloxy-4-ZW-substituted bromobenzene. ______________________________________ ##STR14##R.sub.2 Z W______________________________________CH.sub.3 C(CH.sub.3).sub.2 (CH.sub.2).sub.6 H(CH.sub.2).sub.2 CH.sub.3 C(CH.sub.3).sub.2 (CH.sub.2).sub.6 HCH.sub.2 CH(CH.sub.3).sub.2 C(CH.sub.3).sub.2 (CH.sub.2).sub.6 H(CH.sub.2).sub.4 OCH(CH.sub.3)(CH.sub.2).sub.3 C.sub.6 H.sub.5CH.sub.2 CH(C.sub.2 H.sub.5).sub.2 OCH(CH.sub.3)(CH.sub.2).sub.3 C.sub.6 H.sub.5CH(CH.sub.3)CH.sub.2 CH.sub.3 CH.sub.2 OCH.sub.2 H(CH.sub.2).sub.5 CH.sub.3 CH.sub.2 O(CH.sub.2).sub.4 C.sub.6 H.sub.5CH.sub.2 CH(CH.sub.3)(CH.sub.2).sub.2 CH.sub.3 CH.sub.2 O(CH.sub.2).sub.12 4-FC.sub.6 H.sub.4CHCH.sub.2 CH.sub.2 OCH.sub.2 CH(C.sub.2 H.sub.5)CH.sub.2 4-pyridylCH.sub.2 CHCH.sub.2 CH.sub.2).sub.2 O(CH.sub.2).sub.2 HCH.sub.2 CHCHCH.sub.3 (CH.sub.2).sub.3 O(CH.sub.2).sub.3 H(CH.sub.2).sub.2 CHCH.sub.2 (CH.sub.2).sub.3 O(CH.sub.2).sub.5 HCH.sub.2 CHCH(CH.sub.2).sub.2 CH.sub.3 (CH.sub.2).sub.5 O(CH.sub.2).sub.8 HCH.sub.2 CHCH.sub.2 (CH.sub.2).sub.6 O(CH.sub.2).sub.7 C.sub.6 H.sub.5C(CH.sub.3)CHCH.sub.2 CH(CH.sub.3)(CH.sub.2).sub.2 O(CH.sub.2).sub.4 HC(CH.sub.3)CHCHCH.sub.3 (CH.sub.2).sub.6 O C.sub.6 H.sub.5CH.sub.2 C(CH.sub.3)CH.sub.2 (CH.sub.2).sub.13 O 2-pyridyl(CH.sub.2).sub.4 CHCH.sub.2 CH(CH.sub.3)(CH.sub.2).sub.2 O C.sub.6 H.sub.5CHCHCH.sub.3 (CH.sub.2).sub.8 O 4-pyridylCH.sub.3 CO (CH.sub.2).sub.3 O 2-pyridylCH.sub.3 CH.sub.2 CO (CH.sub.2).sub.3 OCH(CH.sub.3) C.sub.6 H.sub.5CH.sub.3 (CH.sub.2).sub.2 CO C(CH.sub.3).sub.2 (CH.sub.2).sub.5 H(CH.sub.3).sub.2 CHCH.sub.2 CO O(CH.sub.2).sub.5 4-FC.sub.6 H.sub.4CH.sub.3 (CH.sub.2).sub.5 CO O(CH.sub.2 ).sub.13 C.sub.6 H.sub.5(CH.sub.3).sub.2 CHCO OCH(CH.sub.3)(CH.sub.2).sub.3 C.sub.6 H.sub.5(CH.sub.3).sub.2 C(CH.sub.3)CO OCH(CH.sub.3)(CH.sub.2).sub.3 4-ClC.sub.6 H.sub.4(C.sub.2 H.sub.5).sub.2 CHCO (CH.sub.2).sub.4 O(CH.sub.2).sub.5 4-pyridyl(C.sub.2 H.sub.5).sub.2 CHCH.sub.2 CO (CH.sub.2).sub.8 O(CH.sub.2).sub.5 4-pyridylHCO CH.sub.2 HCH.sub.3 OCO CH.sub.2 C.sub.6 H.sub.5C.sub.2 H.sub.5 OCO OCH.sub.2 HC.sub.2 H.sub.5 OCO OCH.sub.2 C.sub.6 H.sub.5CH.sub.3 OCO (CH.sub.2).sub.4 OCH.sub.2 HCH.sub.3 OCO CH.sub.2 O(CH.sub.2).sub.12 Hn-C.sub.3 H.sub.7 OCO CH.sub.2 OCH.sub.2 C.sub.6 H.sub.5n-C.sub.3 H.sub.7 OCO (CH.sub.2).sub.2 O(CH.sub.2).sub.2 Hi-C.sub.4 H.sub.9 OCO C(CH.sub.3).sub.2 (CH.sub.2).sub.6 Hn-C.sub.5 H.sub.11 OCO C(CH.sub.3).sub.2 (CH.sub.2).sub.6 Hn-C.sub.6 H.sub.13 OCO OCH(CH.sub.3)(CH.sub.2).sub.3 C.sub.6 H.sub.5i-C.sub.4 H.sub.9 OCO OCH(CH.sub.3)(CH.sub.2).sub.3 4-ClC.sub.6 H.sub.4sec-C.sub.5 H.sub.11 OCO (CH.sub.2).sub.5 H______________________________________ EXAMPLE 23 Sodium borohydride reduction of the 4-piperidones prepared in Examples 20-22 by the method of Example 2 similarly provides the corresponding 4-hydroxypiperidines of the formula below where R 1 is benzyl. ##STR15## Catalytic hydrogenolysis employing a palladium catalyst and the method of Example 4 likewise provides the corresponding phenols where R 1 is hydrogen. In each case R 2 , Z and W are as defined in Examples 20-22. EXAMPLE 24 cis-2-[(5-phenyl-2-pentyloxy)-2-hydroxyphenyl]-4-piperidinol Hydrolysis of N-ethoxycarbonyl-2-[2-benzyloxy-4-(5-phenyl-2-pentyloxy)phenyl]-4-piperidinol by the procedure of Example 3 and subsequent hydrogenolysis by the procedure of Example 4 provides the title compound in like manner. Similarly the compounds of the formula below are obtained from the remaining N-alkoxycarbonyl compounds provided in Example 23 ##STR16## where Z and W are as defined in Examples 21 and 22. EXAMPLE 25 cis-N-Methyl-2-[4-(5-phenyl-2-pentyloxy)-2-hydroxyphenyl]-4-piperidinol Lithium aluminum hydride reduction of N-ethoxycarbonyl-2-[4-(5-phenyl-2-pentyloxy)-2-benzyloxyphenyl]-4-piperidone or the corresponding 4-piperidinol by the method described in Example 5 and debenzylation by the method of Example 6 provides the title compound. In similar manner the compounds of the formula below are obtained ##STR17## where R 1 is H or benzyl, R 2 is methyl and Z and W are as defined for the starting materials provided in Examples 21-23. In like manner the corresponding N-alkyl compounds [R 2 =(C 2 -C 6 )alkyl] are obtained when the alkanoylamides provided in Example 22 are employed as starting material. EXAMPLE 26 N-Propyl-cis-2-[4-(5-phenyl-2-pentyloxy)-2-hydroxyphenyl]-4-piperidinol Acylation of 2-[4-(5-phenyl-2-pentyloxy)-2-benzyloxyphenyl]-4-piperidinol with propionic anhydride by the method of Example 8, followed by lithium aluminum hydride reduction of the resulting N,O-dipropionyl intermediate by the method of Example 9, Part A, and finally, debenzylation by the method of Example 9, Part B, provides the title compound in like manner. Similarly, the reaction of piperidinol bases provided in Examples 3 and 24 by the above reaction sequence, but employing the appropriate acid anhydride or acid chloride in place of propionic anhydride, provides the corresponding compounds as shown in the following reaction sequence: ##STR18## Z and W are as defined in Examples for the starting piperidinol and R 6 is an (C 1 -C 6 )alkyl residue. EXAMPLE 27 N-Isobutyl-2-[2-hydroxy-4-(1,1-dimethylheptyl)phenyl]piperidine A. N-Isobutyl-2-[2-benzyloxy-4-(1,1-dimethylheptyl)phenyl]piperidine A mixture of 2.32 g (5 mmoles) of N-isobutyl-2-[2-benzyloxy-4-(1,1-dimethylheptyl)phenyl]-4-piperidone, 10.2 ml hydrazine hydrate and 20 ml ethylene glycol is heated at 100° C. for one hour. The mixture is cooled to 60° C, and 4.05 g (72.3 mmoles) solid potassium hydroxide is added. After heating at 200° C. for two hours, the reaction mixture is cooled and added to 500 ml 1N hydrochloric acid and 300 ml ethyl ether. The ether layer is separated, washed with brine, sodium bicarbonate solution, dried over magnesium sulfate and the solvent evaporated at reduced pressure. The crude product is purified, if desired, by column chromatography on silica gel. B. Debenzylation of the product obtained in Part A by the method of Example 4 provides the title compound. C. In like manner the remaining N-alkyl piperidones and N-alkenylpiperidones provided in Example 22 are converted to the corresponding piperidine compounds of the formula ##STR19## where R 2 is an alkyl or alkenyl residue as defined in Example 22. EXAMPLE 28 Employing the appropriate alkenyl bromide, alkenyl chloride or alkenyl iodide and the appropriate 2-[2-benzyloxy-4-(ZW-substituted)phenyl]-4-piperidinol in the procedure of Example 10 provides the corresponding compound of the formula below where R 1 is benzyl. Removal of the benzyl group by the procedure of Example 4 yields the compound where R 1 is H. In each case R 2 is a (C 2 -C 6 )alkenyl group and Z and W are as defined in Example 22. ##STR20## EXAMPLE 29 By means of the procedures of Examples 12 through 19, above, but employing the appropriate starting materials in each case, the following compounds are obtained in like manner. ______________________________________ ##STR21##R.sub.2 Z W______________________________________CH.sub.3 OCO CH.sub.2 HC.sub.2 H.sub.5 OCO OCH.sub.2 C.sub.6 H.sub.5CH.sub.3 OCO (CH.sub.2).sub.4 O(CH.sub.2).sub.2 Hn-C.sub.3 H.sub.7 OCO CH.sub.2 OCH.sub.2 C.sub.6 H.sub.5i-C.sub.4 H.sub.9 OCO OCH.sub.2 (CH.sub.3)(CH.sub.2).sub.3 4-ClC.sub.6 H.sub.4n-C.sub.6 H.sub.13 OCO OCH(CH.sub.3)(CH.sub.2).sub.3 C.sub.6 H.sub.5C.sub.2 H.sub.5 OCO C(CH.sub.3).sub.2 (CH.sub.2).sub.4 4-pyridylCH.sub.3 CH.sub.2 SO.sub.2 C(CH.sub.3).sub.2 (CH.sub.2).sub.6 HCH.sub.3 SO.sub.2 OCH(CH.sub.3)(CH.sub.2).sub.3 C.sub.6 H.sub.5i-C.sub.3 H.sub.7 SO.sub.2 (CH.sub.2).sub.11 Hn-C.sub.3 H.sub.7 SO.sub.2 C(CH.sub.3).sub.2 (CH.sub.2).sub.10 C.sub.6 H.sub.5n-C.sub.4 H.sub.9 SO.sub.2 O(CH.sub.2).sub.4 4-FC.sub.6 H.sub.4i-C.sub.4 H.sub.9 SO.sub.2 CH.sub.2 OCH(CH.sub.3)(CH.sub.2).sub.4 2-pyridylsec-C.sub.4 H.sub.9 SO.sub.2 O(CH.sub.2).sub.2 4-pyridyln-C.sub.5 H.sub.11 SO.sub.2 OCH(CH.sub.3)(CH.sub.2).sub.3 C.sub.6 H.sub.5(CH.sub.3).sub.2 CH(CH.sub.2).sub.3 SO.sub.2 OCH(CH.sub.3)(CH.sub.2).sub.3 4-ClC.sub.6 H.sub.4HOCH.sub.2 CO OCH(CH.sub.3)(CH.sub.2).sub.3 C.sub.6 H.sub.5HOCH.sub.2 CH.sub.2 OCH(CH.sub.3)(CH.sub.2).sub.3 C.sub.6 H.sub.5HO(CH.sub.2).sub.2 CO OCH(CH.sub.3)(CH.sub.2).sub.3 C.sub.6 H.sub.5HO(CH.sub.2).sub.2 CH.sub.2 OCH(CH.sub.3)(CH.sub.2).sub.3 C.sub.6 H.sub.5CH.sub.3 CH(OH)CO CH(CH.sub.3)(CH.sub.2).sub.4 HCH.sub.3 CH(OH)CH.sub.2 C(CH.sub.3).sub.2 (CH.sub.2).sub.4 HHO(CH.sub.2).sub.3 CO C(CH.sub.3).sub.2 (CH.sub.2).sub.4 HHO(CH.sub.2).sub.3 CH.sub.2 C(CH.sub.3).sub.2 (CH.sub.2).sub.4 HHO(CH.sub.2).sub.4 CO OCH(CH.sub.3)CH(CH.sub.3)(CH.sub.2).sub.4 C.sub.6 H.sub.5HO(CH.sub.4)CH.sub.2 OCH(CH.sub.3 )CH(CH.sub.3)(CH.sub.2).sub.4 C.sub.6 H.sub.5CH.sub.3 CH.sub.2 CH(OH)CH.sub.2 CO (CH.sub.2).sub.4 O(CH.sub.2).sub.4 2-pyridylCH.sub.3 CH.sub.2 CH(OH)CH.sub.2 CH.sub.2 (CH.sub.2).sub.4 O(CH.sub.2).sub.4 2-pyridylCH.sub.3 (CH.sub.2).sub.2 CH(OH)CH.sub.2 CO (CH.sub.2).sub.4 O(CH.sub.2).sub.9 HHO(CH.sub.2).sub.6 CO (CH.sub.2).sub.9 O(CH.sub.2).sub.4 HHO(CH.sub.2).sub.6 CH.sub.2 (CH.sub.2).sub.9 O(CH.sub.2).sub.4 HCH.sub.3 (CH.sub.2).sub.4 CH(OH)CO OCH(CH.sub.3)(CH.sub.2).sub.3 C.sub.6 H.sub.5CH.sub.3 (CH.sub.2).sub.4 CH(OH)CH.sub.2 OCH(CH.sub.3)(CH.sub.2).sub.3 C.sub.6 H.sub.5CHO OCH(CH.sub.3)(CH.sub.2).sub.3 C.sub.6 H.sub.5CHO (CH.sub.2).sub.3 O(CH.sub.2).sub.3 HCH.sub.3 CO OCH(CH.sub.3)(CH.sub.2).sub.3 C.sub.6 H.sub.5CH.sub.3 CH.sub.2 CO (CH.sub.2).sub.4 O C.sub.6 H.sub.5(CH.sub.3).sub.2 CHCO (CH.sub.2).sub.3 O 4-ClC.sub.6 H.sub.4CH.sub.3 (CH.sub.2).sub.3 CO OC(CH.sub.3 ).sub.2 (CH.sub.2).sub.4 HHCCCO OCH(CH.sub.3)(CH.sub.2).sub.3 C.sub.6 H.sub.5HCCCH.sub.2 CO OCH(CH.sub.3)(CH.sub.2).sub.3 C.sub.6 H.sub.5CH.sub.3 CCCH.sub.2 CO OCH(CH.sub.3)(CH.sub.2).sub.3 C.sub.6 H.sub.5HCC(CH.sub.2).sub.4 CO C(CH.sub.3).sub.2 (CH.sub.2).sub.6 HCH.sub.3 (CH.sub.2).sub.3 CCCO C(CH.sub.3).sub.2 (CH.sub.2).sub.6 HCH.sub.3 CH.sub.2 CCCH.sub.2 CO OCH(CH.sub.3)(CH.sub.2).sub.3 C.sub.6 H.sub.5HCCCH.sub.2 OCH(CH.sub.3)(CH.sub.2).sub.3 C.sub.6 H.sub.5CHCCH.sub.2 (CH.sub.2).sub.2 O(CH.sub.2).sub.4 HHC CCH.sub.2 CH(CH.sub.3)(CH.sub.2).sub.3 O C.sub.6 H.sub.5CH.sub.3 CCCH.sub.2 (CH.sub.2).sub.4 O 4-pyridylHCC (CH.sub.2).sub.3 O 2-pyridylHCC OCH(CH.sub.3)(CH.sub.2).sub.3 C.sub.6 H.sub.5CH.sub.3 CH.sub.2 CCCH.sub.2 OCH(CH.sub.3)(CH.sub.2).sub.3 4-ClC.sub.6 H.sub.5CH.sub.3 CHCC(CH.sub.2).sub.2 C(CH.sub.3).sub.2 (CH.sub.2).sub.3 HCH.sub.3 (CH.sub.2).sub.2 CCCH.sub.2 C(CH.sub.3).sub.2 (CH.sub.2).sub.3 2-pyridyl______________________________________ EXAMPLE 30 N-n-Butyryl-2-[2-hydroxy-4-(5-phenyl-2-pentyloxy)phenyl]-4-piperidone A. To a cooled solution of 25.8 g (50 mmol) N-n-butyryl-2-[benzyloxy-4-(5-phenyl-2-pentyloxy)phenyl]-4-piperidinol, 100 ml acetone, 6.0 g. (60 mmole) chromium trioxide, 15 ml water and 20 ml acetic acid is added dropwise 20 ml concentrated sulfuric acid at such a rate as to maintain the temperature at 5° C. The resulting mixture is stirred at 5°-20° C. for five hours, and then neutralized with ammonium hydroxide. The mixture is extracted with ethyl ether, the extracts washed with brine, dried (MgSO 4 ) and the solvent evaporated. The resulting crude material is purified by chromatography on silica gel to afford N-n-butyryl-2-[2-benzyloxy-4-(5-phenyl-2-pentyloxy)phenyl]-4-piperidone. B. A mixture of 5 g of the benzyl ether obtained in Part A is dissolved in 100 ml ethanol and 100 ml ethyl acetate. To this is added 2 g of 10% palladium on carbon catalyst and the mixture is stirred under one atmosphere of hydrogen for 3 hours. The product is isolated and purified by the method of Example 4. C. The remaining 4-piperidinols provided above are converted to the corresponding 4-piperidones of the formula below in like manner. ##STR22## EXAMPLE 31 N-Propyl-2-[2-(4-N-piperidylbutyryloxy)-4-(1,1-dimethylheptyl)phenyl]-4-piperidinone Hydrochloride To a solution of 0.9 g (2.5 mmole) N-propyl-2-[2-hydroxy-4-(1,1-dimethylheptyl)phenyl]-4-piperidinone in 25 ml methylene chloride is added 0.52 g (2.5 mole) 4-piperidylbutyric acid hydrochloride, 0.573 g (2.78 mmole) dicyclohexylcarbodiimide and the mixture is stirred at room temperature for six hours. After holding overnight at 0° C., the mixture is filtered, the filtrate evaporated and the residue triturated with ethyl ether to afford the desired hydrochloride salt. Alternatively, the filtrate is extracted with dilute hydrochloric acid. The aqueous phase washed with ether, neutralized with potassium hydroxide solution and extracted with ether. Evaporation affords the free base of the title compound. Repetition of this procedure, but employing the appropriate phenol of the formula below where R 1 is H, and the appropriate carboxylic acid in place of 4-piperidylbutric acid hydrochloride provides the following compounds in like manner ##STR23## where R 2 , R 3 , Z and W are as defined above and R 1 is as shown below. R 1 COCH 2 CH 3 CO(CH 2 ) 2 CH 3 CO(CH 2 ) 3 CH 3 COCH 2 NH 2 CO(CH 2 ) 2 NH 2 CO(CH 2 ) 4 NH 2 CO(CH 2 )N(CH 3 ) 2 CO(CH 2 ) 2 NH(C 2 H 5 ) CO(CH 2 ) 4 NHCH 3 CONH 2 CON(C 2 H 5 ) 2 CON(C 4 H 9 ) 2 CO(CH 2 ) 3 NH(C 3 H 7 ) CO(CH 2 ) 2 N(C 4 H 9 ) 2 COCH 2 -piperidino COCH 2 -pyrrolo CO(CH 2 ) 2 -morpholino CO(CH 2 ) 2 -N-butylpiperazino CO(CH 2 ) 3 -pyrrolidino CO-piperidino CO-morpholino CO-pyrrolo CO--N-(methyl)piperazino CO--C 6 H 5 COCH(CH 3 )(CH 2 ) 2 -piperidino CHO Basic esters are obtained as their hydrochloride salts. Careful neutralization with sodium hydroxide affords the free basic esters. EXAMPLE 32 General Hydrochloride Acid Addition Salt Formation Into an ethereal solution of the appropriate free base of formula (I), having one or more basic nitrogen containing groups, is passed a molar excess of anhydrous hydrogen chloride and the resulting precipitate is separated and recrystallized from an appropriate solvent, e.g. methanol-ether. Similarly, the free bases of formula (I) are converted to their corresponding hydrobromide, sulfate, nitrate, phosphate, acetate, butyrate, citrate, malonate, maleate, fumarate, malate, glycolate, gluconate, lactate, salicylate, sulfosalicylate, succinate, pamoate and tartarate salts. EXAMPLE 33 N-Butyryl-cis-2-[4-(1,1-dimethylheptyl)-2-hydroxyphenyl]-4-piperidinol, 100 mg, is intimately mixed and ground with 900 mg of starch. The mixture is then loaded into telescoping gelatin capsules such that each capsule contains 10 mg of drug and 90 mg of starch. EXAMPLE 34 A tablet base is prepared by blending the ingredients listed below: ______________________________________Sucrose 80.3 partsTapioca starch 13.2 partsMagnesium stearate 6.5 parts______________________________________ N-Ethoxycarbonyl-cis-2-[4-(1,1-dimethylheptyl)-2-hydroxyphenyl]-4-piperidinol is blended into this base to provide tablets containing 0.1, 0.5, 1, 5, 10 and 25 mg of drug. EXAMPLE 35 Suspensions of N-n-pentanoyl-cis-2-[4-(1,1-dimethylheptyl)-2-hydroxyphenyl]-4-piperidinol hydrochloride are prepared by adding sufficient amounts of drug to 0.5% methylcellulose to provide suspensions having 0.05, 0.1, 0.5, 1, 5 and 10 mg of drug per ml.

2-[2-Hydroxy-4-(substituted)phenyl]piperidines and derivatives thereof of the formula ##STR1## or a pharmaceutically acceptable acid addition salt thereof, wherein R 1 is H, benzyl or certain acyl groups, R 2 is H, certain alkyl, alkenyl, alkynyl, hydroxyalkyl, acyl or alkylsulfonyl groups; R 3 is H 2 , O, ##STR2## and Z is (C 1 -C 13 )alkylene or -(alk 1 ) m -O-(alk 2 ) n - where each of (alk 1 ) and (alk 2 ) is (C 1 -C 13 )alkylene, provided that the number of carbon atoms in (alk 1 ) plus (alk 2 ) is not greater than 13; each of m and n is 0 or 1; and W is H, pyridyl or optionally substituted phenyl; their use as analgesic agents, intermediates therefor and processes for their preparation.

BACKGROUND OF THE INVENTION [0001] 1. Field of the Invention [0002] The invention concerns a cosmetic product that includes a flowable cosmetic composition dispensed from a heating device wherein the composition has extended heat retention. [0003] 2. The Related Art [0004] Heated lotions have several benefits. A fleeting unpleasant wince may occur when a cold fluid is first topically applied to human skin. Warmed lotions do not elicit the same negative response. [0005] Warmed cosmetic fluids are believed to better penetrate the skin. Warmth is viewed as an assistance in opening pores. This allows deeper penetration into the skin of the cosmetic fluid. [0006] Therapeutic effects may also be achievable by heated lotions. These may mitigate joint aches, sore muscles and other body tightness. For all these reasons, mechanical devices have been developed to heat cosmetic fluids. [0007] U.S. Pat. No. 6,216,911 B1 (Kreitemier et al.) describes an apparatus for quickly heating a predetermined volume of viscous fluid. The fluid is then efficiently dispensed at one or more selected temperatures. In one embodiment, the predetermined volume of viscous fluid is partially housed in a predelivery chamber separate from the main fluid reservoir. An apparatus described by this patent is commercially available from New Sensations LLC, Englewood, Colo. under the brand New Sensation Lotion Spa. [0008] U.S. Patent Application Publication 2002/0108965 A1 (Hill et al.) discloses a fluid heating and dispensing device with a first reservoir, a second reservoir, a pump, a heating device and a delivery device. This document appears to describe a commercially available apparatus from Conair Corporation under the designation HLD 31 and HLD 20. [0009] U.S. Pat. No. 6,056,160 (Carlucci et al.) reports a device for heating and dispensing, to a user through an outlet, a foaming liquid such as shaving cream from a pressurized can. [0010] With the advent of suitable delivery devices, a need has developed to improve the cosmetic fluids dispensed therefrom. An important problem to be solved is the extension of the heating effect for the cosmetic composition subsequent to being dispensed. SUMMARY OF THE INVENTION [0011] A cosmetic product for use with a heating device is provided which includes: (i) a cosmetic composition having from about 0.01 to about 20% by weight of porous particles having an average particle size ranging from about 0.1 to about 100 μm in a cosmetically acceptable carrier; (ii) a package containing the cosmetic composition; and (iii) instructions associated with the package describing use of the cosmetic composition which includes charging the cosmetic composition into the heating device, applying heat to the composition, thereafter activating a dispensing mechanism associated with the device and transferring dispensed heated composition to a human body. [0015] A method for treating skin is provided which includes: (i) providing a cosmetic composition including from about 0.01 to about 20% by weight of porous particles having an average particle size ranging from about 0.1 to about 100 μm in a cosmetically acceptable carrier; (ii) providing a heating device including a chamber for receiving a flowable cosmetic composition, a heating element for imparting heat to the cosmetic composition, and an outlet for dispensing heated cosmetic composition; and (iii) applying dispensed heated cosmetic composition onto the skin. DETAILED DESCRIPTION OF THE INVENTION [0019] Now it has been found that a heated flowable cosmetic composition can longer retain heat when formulated with even a small amount of porous particles. Upon being placed onto skin, the porous particle fortified compositions maintain warmth on the skin for the critical few seconds to minutes after initial application. [0020] Dispensing devices for heating cosmetic fluid compositions as noted above have been described in U.S. Pat. No. 6,216,911 B1; U.S. Patent Application Publication 2002/0108965 A1 and U.S. Pat. No. 6,056,160, the specifications of which are herein incorporated by reference. Also there are commercial devices available. One device is sold by Conair Corporation of Stamford, Conn. and another by New Sensations LLC of Englewood, Colo. [0021] Heating devices of the present invention are best operated to deliver a composition that exhibits a dispensed temperature between about 30° to about 60° C., more preferably from 36° C. to 54° C., even more preferably from 380 to 49° C. and optimally from 40° to 46° C. [0022] Porous particles of the present invention in preferred embodiments may allow a 10 gram dispensed unit of cosmetic composition to maintain an elevated temperature relative to a composition absent those particles. The elevated temperature may range from 1.50 to 10° C., preferably from 2° to 8° C., optimally from 3° to 6° C. dependent on the level of porous particles formulated into the composition. Maintenance of the elevated temperature may range from 5 seconds to about 10 minutes, preferably from 15 seconds to 5 minutes, more preferably from 10 seconds to 2 minutes, and optimally from 20 seconds to 1 minute upon skin after being dispensed. [0023] Porous particles of the present invention may either be organic or inorganic. Preferably but not necessarily, the particles may be formed as spherical beads. The particles preferably are water-insoluble and polymeric. [0024] By the term “porous” is meant an open or closed cell structure. Preferably the particles are hollow beads. Average particle size may range from about 0.1 to about 100, preferably from about 0.5 to about 50, more preferably from 1 to about 15, optimally from about 3 to about 10 μm. [0025] Representative inorganic materials of this invention are silicas such as Spheron® P-1500 sold by Presperse Inc. However, organic polymers or copolymers are the preferred materials. These can be formed from monomers including the acid, salt or ester forms of acrylic acid, methacrylic acid, methyl methacrylate, ethylacrylate, ethylene, propylene, vinylidene chloride, acrylonitrile, maleic acid, vinyl pyrrolidone, styrene, divinylbenzene, butadiene and mixtures thereof. The polymers are especially useful in cross-linked form. Cells of the porous particles may be filled by a gas which can be air, nitrogen or a hydrocarbon. Oil Absorbance (castor oil) is a measure of porosity and may range from about 10 to about 500, preferably from about 80 to about 300, optimally from about 120 to about 180 mI/100 grams. Density of the particles in preferred embodiments may range from about 0.08 to 0.55, preferably from about 0.15 to 0.48 g/cm 3 . [0026] Silicone based materials may be employed as the porous particles, most especially spherical organic silicone particles. These may be chosen from microbeads of methylsilsesquioxane resins. Commercially they are available from Toshiba Silicone under the name Tospearl® 145A. Also suitable are spherical particles of cross-linked polydimethylsiloxanes commercially available from the Dow Corning Toray Silicone Company under the name Trefil E-506C® or Trefil E-505C®. [0027] Non-silicone based porous particles may also be suitable. These include microbeads of poly(methyl methacrylate) such as those sold by Seppic under the name of Micropearl M 100®. Spherical particles of polyamide may also be useful, especially those of Nylon 12 such as those sold by Atochem under the name Orgasol 2002 D Nat C05®. Polystyrene microspheres might also be suitable and are sold by Dyno Particles Company under the name Dynospheres®. Styrene/acrylate copolymer particles also have suitability and are available from Rohm & Haas under the name Ropaque™. [0028] Most preferred for this invention are porous polymers of cross-linked poly(methylmethacrylate). Representative is a poly(methylmethacrylate) named as Ganzpearl GMP 0820® available from Presperse, Inc., Piscataway, N.J., known also by its INCI name of Methyl Methacrylate Crosspolymer. The product specifications of Ganzpearl GMP 0820® include: spherical, white fine powder having a particle size of 4-10.5 μm, preferably 4-8 μm, high oil absorption, and specific gravity of 1.10 to 1.25. Its loss on ignition (400° C.) is less than 0.1%, and on drying (105° C./2 hours) is less than 2.0%. The surface residual monomer content of Ganzpearl GMP 0820® is less than 20 ppm, with total residual monomer content being less than 100 ppm. [0029] Methyl methacrylate crosspolymers are also commercially available from Nihon Junyaku under the trademark Jurymer MP-1P and from Tomer under the trademark Microsphere M-305. [0030] Amounts of the porous particles may range from about 0.01 to about 20%, preferably from about 0.1 to about 10%, more preferably from about 0.25 to about 8%, still more preferably from about 0.5 to about 3%, and optimally from about 0.75 to about 2% by weight of the composition. [0031] Compositions of the present invention will also include a cosmetically acceptable carrier. Water is the most preferred carrier. Amounts of water may range from about 1 to about 99%, preferably from about 5 to about 90%, more preferably from about 35 to about 70%, optimally between about 40 and about 60% by weight. Ordinarily the compositions will be water and oil emulsions of the W/O or O/W variety. [0032] Other cosmetically acceptable carriers may include mineral oils, silicone oils, synthetic or natural esters, fatty acids and alcohols and humectants. Amounts of these materials may range from about 0.1 to about 50%, preferably from about 0.1 to about 30%, more preferably from about 1 to about 20% by weight of the composition. [0033] Silicone oils may be divided into the volatile and non-volatile variety. The term “volatile” as used herein refers to those materials which have a measurable vapor pressure at ambient temperature. Volatile silicone oils are preferably chosen from cyclic or linear polydimethylsiloxanes containing from about 3 to about 9, preferably from about 4 to about 5, silicon atoms. [0034] Linear volatile silicone materials generally have viscosities less than about 5 centistokes at 25° C. while cyclic materials typically have viscosities of less than about 10 centistokes. [0035] Nonvolatile silicone oils useful as carrier material include polyalkyl siloxanes, polyalkylaryl siloxanes and polyether siloxane copolymers. The essentially non-volatile polyalkyl siloxanes useful herein include, for example, polydimethyl siloxanes with viscosities of from about 5 to about 100,000 centistokes at 25° C. [0036] Among suitable esters are: (1) Alkenyl or alkyl esters of fatty acids having 10 to 20 carbon atoms, Examples thereof include isopropyl palmitate, isopropyl isostearate, isononyl isonanonoate, oleyl myristate, oleyl stearate, and oleyl oleate. (2) Ether-esters such as fatty acid esters of ethoxylated fatty alcohols. (3) Polyhydric alcohol esters. Ethylene glycol mono and di-fatty acid esters, diethylene glycol mono- and di-fatty acid esters, polyethylene glycol (200-6000) mono- and di-fatty acid esters, propylene glycol mono- and di-fatty acid esters, polypropylene glycol 2000 monooleate, polypropylene glycol 2000 monostearate, ethoxylated propylene glycol monostearate, glyceryl mono- and di-fatty acid esters, polyglycerol poly-fatty esters, ethoxylated glyceryl monostearate, 1,3-butylene glycol monostearate, 1,3-butylene glycol distearate, polyoxyethylene polyol fatty acid ester, sorbitan fatty acid esters, and polyoxy-ethylene sorbitan fatty acid esters are satisfactory polyhydric alcohol esters. (4) Wax esters such as beeswax, spermaceti, myristyl myristate, stearyl stearate. (5) Sterols esters, of which soya sterol and cholesterol fatty acid esters are examples thereof. [0042] Fatty acids having from 10 to 30 carbon atoms may be included in the compositions of this invention. Illustrative of this category are Ipelargonlc, lauric, myristic, palmitic, stearic, isostearic, hydroxyystearic, oleic, linoleic, ricinoleic, arachidic, behenic and erucic acids. [0043] Humectants of the polyhydric alcohol-type may also be included in the compositions of this invention. The humectant aids in increasing the effectiveness of the emollient, reduces scaling, stimulates removal of built-up scale and improves skin feel. Typical polyhydric alcohols include glycerol (also known as glycerin), polyalkylene glycols and more preferably alkylene polyols and their derivatives, including propylene glycol, dipropylene glycol, polypropylene glycol, polyethylene glycol and derivatives thereof, sorbitol, hydroxypropyl sorbitol, hexylene glycol, 1,3-butylene glycol, 1,2,6-hexanetriol, ethoxylated glycerol, propoxylated glycerol and mixtures thereof. For best results the humectant is preferably glycerin. The amount of humectant may range anywhere from 0.5 to 30%, preferably between 1 and 15% by weight of the composition. [0044] Emulsifiers may be present in cosmetic compositions of the present invention. Total concentration of the emulsifier may range from about 0.1 to about 40%, preferably from about 1 to about 20%, optimally from about 1 to about 5% by weight of the total composition. The emulsifier may be selected from the group consisting of anionic, nonionic, cationic and amphoteric actives. Particularly preferred nonionic surfactants are those with a C 10 -C 20 fatty alcohol or acid hydrophobe condensed with from about 2 to about 100 moles of ethylene oxide or propylene oxide per mole of hydrophobe; C 2 -C 10 alkyl phenols condensed with from 2 to 20 moles of alkylene oxide; mono- and di-fatty acid esters of ethylene glycol; fatty acid monoglyceride; sorbitan, mono- and di- C 8 -C 20 fatty acids; and polyoxyethylene sorbitan as well as combinations thereof. Alkyl polyglycosides and saccharide fatty amides (e.g. methyl gluconamides) are also suitable nonionic emulsifiers. [0045] Preferred anionic emulsifiers include soap, alkyl ether sulfate and sulfonates, alkyl sulfates and sulfonates, alkylbenzene sulfonates, alkyl and dialkyl sulfosuccinates, C 8 -C 20 acyl isethionates, C 8 -C 20 alkyl ether phosphates, alkylethercarboxylates and combinations thereof. [0046] Preservatives can desirably be incorporated into the cosmetic compositions of this invention to protect against the growth of potentially harmful microorganisms. Suitable traditional preservatives for compositions of this invention are alkyl esters of para-hydroxybenzoic acid. Other preservatives which have more recently come into use include hydantoin derivatives, propionate salts, and a variety of quaternary ammonium compounds. Cosmetic chemists are familiar with appropriate preservatives and routinely choose them to satisfy the preservative challenge test and to provide product stability. Particularly preferred preservatives are iodopropynyl butyl carbamate, phenoxyethanol, methyl paraben, propyl paraben, imidazolidinyl urea, sodium dehydroacetate and benzyl alcohol. The preservatives should be selected having regard for the use of the composition and possible incompatibilities between the preservatives and other ingredients in the emulsion. Preservatives are preferably employed in amounts ranging from about 0.01% to about 2% by weight of the composition. [0047] Thickening agents may be included in compositions of the present invention. Particularly useful are the polysaccharides. Examples include starches, natural/synthetic gums and cellulosics. Representative of the starches are chemically modified starches such as aluminum starch octenylsuccinate. Suitable gums include xanthan, sclerotium, pectin, karaya, arabic, agar, guar, carrageenan, alginate and combinations thereof, Suitable cellulosics include hydroxypropyl cellulose, hydroxypropyl methylcellulose, ethylcellulose and sodium carboxy methylcellulose. Synthetic polymers are still a further class of effective thickening agent. This category includes crosslinked polyacrylates such as the Carbomers, polyacrylamides such as Sepigel® 305 and taurate copolymers. Particularly preferred are the taurate copolymers such as Acryloyl Dimethyltaurate/Vinyl Pyrrolidone Copolymer (available commercially as Aristoflex® AVC) and Sodium Acrylate/Acryloyldimethyl Taurate Copolymer (available commercially as Simulgel EG). [0048] Amounts of the thickener may range from about 0.001 to about 5%, preferably from about 0.1 to about 2%, optimally from about 0.2 to about 0.5% by weight. [0049] Colorants, fragrances and abrasives may also be included in compositions of the present invention. Each of these substances may range from about 0.05 to about 5%, preferably between 0.1 and 3% by weight. [0050] Except in the operating and comparative examples, or where otherwise explicitly indicated, all numbers in this description indicating amounts of material ought to be understood as modified by the word “about”. [0051] The term “comprising” is meant not to be limiting to any subsequently stated elements but rather to encompass non-specified elements of major or minor functional importance. In other words the listed steps, elements or options need not be exhaustive. Whenever the words “including” or “having” are used, these terms are meant to be equivalent to “comprising” as defined above. [0052] The following Examples will more fully illustrate the embodiments of this invention. All parts, percentages and proportions referred to herein and in the appended claims are by weight unless otherwise indicated. EXAMPLE 1 [0053] A typical emulsion type cosmetic composition of the present invention is reported in Table 1. [0000] TABLE 1 Component Weight % Glycerin 10.00 Stearic Acid 2.34 Glyceryl Monostearate/Stearamide AMP 1.38 Isopropylmyristate 1.30 Petrolatum 1.25 Silicone 50 ct 1.00 Simulgel EG ® 0.75 Triethanolamine (99%) 0.70 Glycerol Monostearate 0.64 Ganzpearl GMP 0820 ® 0.50 Cetyl Alcohol 0.37 Fragrance 0.30 DMDM Hydantoin 0.17 Titanium Dioxide 0.10 Glydant Plus ® 0.09 Disodium EDTA 0.05 Water Balance [0054] The composition of Table 1 was formulated in the following manner. A reactor was charged with the deionized water and disodium EDTA. Heat was applied till 60° C. in combination with stirred mixing. Simulgel EG® was added to the reactor and the temperature maintained at 77-80° C. for 10 to 15 minutes. In a separate vessel, the oil phase components were added. Light mixing of the batch was performed with heating in a water bath to 75-77° C. The water reactor was maintained at 60-65° C. and slow addition occurred for glycerin, titanium dioxide and triethanolamine. Continuous mixing was done until the aqueous system was uniform. Very slowly the oil phase was added to the water phase at 75-77° C. under moderate mixing. After full emulsification, the batch was agitated for a further 5 minutes. Thereupon the resultant emulsion was homogenized using an ARDE Barenco® apparatus for 20-30 seconds at 35%. The resultant system was then topped with further deionized water. Cooling then began with a large sweep (50 rpm) mixer. Preservatives Glydant Plus® and DMDM Hydantoin were then added with the batch held at 50-55° C. Thereafter a slurry of Ganzpearl GMP 0820® in the silicone oil was added to the batch. At a temperature of 45-50° C., the fragrance was charged to the reactor. Heating was then discontinued and mixing was stopped when the temperature reached 38-40° C. [0055] After formation, the composition was charged into a Conair HLD31® Hot Lotion Dispenser. An essentially identical composition but without the porous cross-linked poly(methlymethacrylate), Ganzpearl GMP 0820®, was prepared in parallel and placed into a separate Conair HLD31® Hot Lotion Dispenser. Approximately a 10 gm amount of each of the compositions was dispensed from the Conair appliance onto left and right hands, respectively of several evaluators. The composition that included Ganzpearl® noticeably retained heat longer than the control sample without the Ganzpearl®. EXAMPLE 2 [0056] Experiments were conducted to quantitivately evaluate the heat retention effect of Ganzpearl® in formulas according to the present invention in the context of dispensing from a heated lotion appliance. A series of five formulas with different levels of Ganzpearl® were evaluated. These formulas utilized the composition of Example 1, except for variation in the level of Ganzpearl®. [0057] Time to cool subsequent to dispensing from the hot lotion appliance was measured according to the following procedure. A liquid crystal film sourced from Educational Innovations Inc., Norwalk, Conn. served as the temperature sensor. This film displays colors as a function of temperature between 30 and 35° C. This temperature range was selected based on typical skin surface temperatures of 32°. A Gardener Wet Film Applicator Rod (No. 22) was employed to create a uniform wet film (56.4 micron thickness) of each sample lotion on the liquid crystal film. The color of the film was recorded each minute until the film surface had cooled below 30° C. The color was then converted into temperature values with a color scale obtained by calibrating the film's color in an oven. [0058] Samples were run side-by-side. Always the sample without Ganzpear® was placed adjacent those with varying levels of this material. One side of the film, attached to a board to facilitate the casting process, consistently cooled faster. This was measured in use to normalize the data against baseline. Table 2 summarizes the results showing effects of the addition of Ganzpearl® on the time to cool from 35° C. to 30° C. [0000] TABLE 2 Weight % Ganzpearl % Increase In Time To Cool 0.00 — 0.25  6 0.50 32 0.75 81 1.00 87 [0059] Evident from the results is that even small amounts of Ganzpearl® had a significant effect upon increasing the “time to cool”. After 1% Ganzpearl®, the effect appears to plateau.

A product and method for treating skin with a heated lotion is herein described. The product is a packaged cosmetic composition with associated instructions for applying to skin a heated form of the cosmetic composition dispensed from a heating device. The cosmetic composition includes porous particles which function to retain heat within the composition to a greater extent than in the absence of the particles.

FIELD OF THE INVENTION This invention belongs to the field of organic chemistry. In particular, this invention relates to a method for invisibly marking or tagging petroleum products for identification purposes. BACKGROUND OF THE INVENTION It is known that the various petroleum hydrocarbons can be marked using colorants. However, there exists a need for invisibly marking petroleum-derived products in order to identify the various grades of fuels, to distinguish manufacturer's brands, and to make misuse impossible or at least traceable. In this regard, it is desirable that the added marker be readily detected by non-scientific personnel. Finally, the marker should be detectable at low enough levels so that the physical and chemical properties of the petroleum product are not appreciably altered. Historically, various problems have accompanied the use of dyes or colorants as markers for petroleum products, including sludging, crystallization, or agglomeration of the dye upon standing or storage. U.S. Pat. Nos. 2,028,637; 2,925,333; 3,004,821; 3,164,449; 3,350,384; 3,435,054; 3,690,809; 3,704,106; 4,009,008; 4,049,393; 4,303,407; and 4,735,631; European Application No. 95 975; and U.S.S.R. Patent No. 297,659 describe the use of colorants and dyes in marking petroleum products. Ger. Offen. 1,913,912; and U.S. Pat. Nos. 4,278,444, 4,992,204; and 5,279,967 describe visible or ultraviolet fluorescing compounds useful as markers in petroleum products. The marking or tagging systems based on UV fluorescence have the inherent disadvantage that many of the petroleum hydrocarbons themselves contain condensed aromatic compounds which fluoresce when exposed to UV radiation. U.S. Pat. No. 5,201,921 describes a method for marking plastic with UV fluorescent compounds. U.S. Pat. No. 4,540,595 teaches the marking of documents such as bank checks with certain fluorescent phenoxazine dyes. U.S. Pat. No. 5,093,147 describes the use of polymethine infrared fluorescent compounds in bar codes. U.S. Pat. No. 3,630,941 describes 16,17-dialkoxy-violanthrones vat dyes for use as infrared fluorescers for marking articles. All of the above infrared fluorophores lack adequate solubility in most petroleum hydrocarbons to be suitable for such use. This invention provides a method for marking or tagging various petroleum products, for identification purposes. Preferably, the markers of the present invention are squaraines, phthalocyanines, or naphthalocyanines which fluoresce in the near infrared region when exposed to near infrared light. Also provided are certain near infrared fluorophoric compounds which are soluble in petroleum hydrocarbons. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 depicts an apparatus useful for practicing the present invention for identification of the near infrared (NIR) marker in the petroleum products as described herein. This arrangement will be understood to be an application of commercially available fluorometers. As may be seen from FIG. 1, there is present a light source (1) capable of emitting radiation in the visible and NIR region which illuminates the near infrared fluorophore-marked sample (2) through a wavelength selector (3) e.g., monochromator or interference filter. A wavelength selector (4) and a NIR sensitive photodetector (5) is placed at 90° or less angle. It may be seen from FIG. 1 that light source (1), wavelength selector (3 & 4) and photodetector (5) are all arranged on two sides of a triangle to minimize scattered light entering the detector. The light source (1) in FIG. 1 may be replaced with lasers, preferably semiconductor lasers. The output of photodetector (5) is provided to level adjustment amplifier (6), the output of which is provided to an integrated circuit digital multimeter (7). The output of the digital multimeter is connected to a computer display so as to provide a numeral and graphical indication of the amount of luminous flux at the predetermined wavelength (preferably at the emission maxima) emitted by the substance contained in sample. FIG. 2 shows a preferred apparatus useful for practice of the present invention which will be understood to be a specialized arrangement for performing the tests of the present invention. As may be seen from FIG. 2, there is present a laser diode light source (1) capable of emitting radiation in the NIR region which is collimated through a collimating lens (2), and illuminates the sample (4) through an optical filter (3). A focusing lens (5) and a beam compressor are placed at 30 degrees or less angle. It may be seen from FIG. 2 that the laser diode light source and the collimating lens are arranged to minimize scattered light from entering the detector. An optical filter (6) is placed between the compressor lenses (7 & 8) to select the wavelength of fluorescence of the tagging molecule which is focused on the photodetector. A current-to-voltage converter is connected to the photodetector (9) to amplify the detector signal. The arrangement and the electronic circuitry of the current-to-voltage amplifying (10) is widely known and the routines of amplifying and processing the photodetector signal are also well-known. The signal from the current-to-voltage converter circuit is detected by a threshold detector (11). The threshold level of the threshold detector is set at the level required to minimize any interference from unmarked samples. The presence of tagged samples in front of the preferred apparatus is indicated by the light-emitting diode (LED) indicator (12). FIGS. 1 and 2 are more fully described below. SUMMARY OF THE INVENTION The present invention provides a method for tagging, for identification purposes, a petroleum product which comprises dissolving in said product a near infrared fluorophoric compound. As a further aspect of the invention there is provided a petroleum product having dissolved therein at least one near infrared fluorophoric compound. As a further aspect of the invention, there is provided a method for identifying a petroleum product, wherein said product has one or more near infrared fluorophoric compounds dissolved therein, which comprises the steps: (a) exposure of a petroleum hydrocarbon composition to electromagnetic radiation having wavelengths of 670-850 nm, wherein said petroleum hydrocarbon composition comprises a petroleum hydrocarbon material having dissolved therein one or more near infrared fluorescent tagging compounds, wherein said tagging compound(s) is (are) present in a concentration sufficient to impart detectable fluorescence when exposed to electromagnetic radiation of about 670-850 nm provided by light sources; followed by (b) detection of the emitted fluorescent radiation by near infrared detection means. DETAILED DESCRIPTION OF THE INVENTION In the practice of the present invention, it is possible to mark, for example, one grade of gasoline with one near infrared flurophoric compound and another grade with a near infrared fluorophoric marker which fluoresces at a detectably different wavelength. In this fashion, the identity of a certain grade of gasoline can be confirmed without resorting to chemical analysis. Ideally, the near infrared fluorophores useful in the practice of the invention should possess the following properties: 1. adequate solubility in petroleum hydrocarbons to allow easy dissolution to give concentrations of infrared fluorophore detectable by available infrared detectors; 2. strong absorbance of infrared light in the 670-850 nm wavelength range; 3. little or no absorbance in the 400 to about 670 nm range (visible), to permit essentially "invisible" markings; 4. strong infrared fluorescence when irradiated with infrared radiants having wavelengths of about 670-850 nm; 5. give detectable emission levels when added to petroleum hydrocarbons at extremely low levels, e.g. 1 ppm or less. 6. have adequate stability, e.g. to sunlight, water, oxygenates, temperature, etc. 7. be environmentally safe. It is also within the scope of the invention to mark one or more petroleum hydrocarbons with two or more infrared fluorophores, said fluorescing compounds having been selected so that they absorb infrared and/or reemit fluorescent light at wavelengths different enough from each other as not to interfere with individual detection. It is preferred that the infrared fluorophores absorb strongly at wavelengths below about 850 nm, since petroleum hydrocarbons have inherent interfering absorption of wavelengths above about 850 nm. Growing concern about pollution from the use of petroleum fuels requires that any marker for petroleum hydrocarbons be added at the lowest levels possible to minimize any discharges into the atmosphere during combustion. Thus, the infrared fluorophore is preferably added at the lowest levels needed to produce a consistently detectable signal, preferably at about 1 ppm or less, by near infrared detection means, when irradiated by a light source. The term "light sources" refers to devices used to irradiate the samples with near infrared radiation having wavelength outputs from 670 to 850 nm such as laser diodes, solid state lasers, dye lasers, incandescent, or any other known light source. Such light sources can be used in conjunction with wavelength selectors such as filters, monochromators, etc. The preferred light sources are those that have a maximum signal at the maximum of the absorbance of the tagging fluorophore. Examples include the laser diodes, light emitting diodes, or solid state lasers. In the above method, it will be appreciated that near infrared detection means denotes any apparatus capable of detecting fluorescence in the range described herein. Such detection means are the devices for detecting photons emitted by the fluorescent samples at wavelengths of about 670 to 2500 nm such as photomultiplier tubes, solid state detectors, semi-conductor based detectors, or any such device. The preferred means of detection has an optimum sensitivity at the preferred wavelength region. Examples include the silicon photodiodes or germanium detectors. In the above method, the phrase "detectibly different wavelength or wavelengths" refers to phenomenon that fluorescence by one or more of the near infrared fluorophores will occur at a different wavelength (or wavelengths in the case of two or more fluorophores) and such difference will, by necessity be one that is capable of detection. Using state of the art detection equipment it is believed that such differences in absorption/fluorescence of as little as 20 nm in wavelength can be discerned. Of course, this limitation is not critical and will decrease as detection methodology improves. Thus, the presence of a near infrared fluorophore (NIRF) provides highly effective tags for identification of petroleum products. Ideally, as noted above, the NIRF "tag" should have good thermal stability and little light absorption in the visible region; that is they should impart little or no color to the petroleum product to which the NIRF is copolymerized or admixed with. Also, they should have strong absorption of near infrared light (high molar extinction coefficients, e.g., >20,000) and have strong fluorescence in the near infrared over the wavelengths of about 670-2500 nm. To produce essentially "invisible" tags the near infrared fluorescent compounds must absorb little if any light having wavelengths in the 400-670 nm range; however, since the compounds are present in extremely low concentrations, a small amount of absorption may be tolerated without imparting significant color. The preferred near infrared fluorescent compounds which are useful in the practice of the invention are selected from the classes of phthalocyanines, 2,3-naphthalocyaninessquaraines (squaric acid derivatives) and croconic acid derivatives and correspond to Formulae I, II, III, and IV, respectively: ##STR1## wherein Pc and Nc represent the phthalocyanine and naphthalocyanine moieties of Formulae Ia and IIa, ##STR2## respectively, covalently bonded to hydrogen or to various halometals, organometallic groups, and oxymetals including AlCl, AlBr, AlF, AlOR 5 , AlSR 5 , SiCl 2 , SiF 2 , Si(OR 6 ) 2 , Si(SR 6 ) 2 , Zn or Mg, wherein R 5 and R 6 are selected from hydrogen, alkyl, aryl, heteroaryl, alkanoyl, arylcarbonyl, arylaminocarbonyl, trifluoroacetyl, ##STR3## groups of the formula ##STR4## wherein R 7 , R 8 and R 9 are independently selected from alkyl, phenyl or phenyl substituted with alkyl, alkoxy or halogen; X is selected from oxygen, sulfur, selenium, tellurium or a group of the formula N-R 10 , wherein R 10 is hydrogen, cycloalkyl, alkyl, acyl, alkylsulfonyl, or aryl or R 10 and R taken together form an aliphatic or aromatic ring with the nitrogen atom to which they are attached; Y is selected from alkyl, aryl, heteroaryl, halogen or hydrogen; R is selected from hydrogen, unsubstituted or substituted alkyl, alkenyl, alkynyl, C 3 -C 8 cycloalkyl, aryl, heteroaryl, alkylene ##STR5## --(X-R) m is one or more groups selected from alkylsulfonylamino, arylsulfonylamino, or a group selected from the formulae --X(C 2 H 4 O) z R, ##STR6## wherein R is as defined above; Z is an integer of from 1-4; or two --(X-R) m groups can be taken together to form divalent substituents of the formula ##STR7## wherein each X 1 is independently selected from --O--, --S--, or --N-R 10 and A is selected from ethylene; propylene; trimethylene; and such groups substituted with lower alkyl, lower alkoxy, aryl and cycloalkyl; 1,2-phenylene and 1,2-phenylene containing 1-3 substituents selected from lower alkyl, lower alkoxy or halogen; R' and R" are independently selected from lower alkyl and cycloalkyl; R 1 and R 2 are independently selected from hydrogen, alkyl, alkoxy, halogen, aryloxy, alkylthio, arylthio, alkylsulfonyl, arylsulfonyl, alkylsulfonylamino, arylsulfonylamino, cycloalkylsulfonylamino, unsubstituted and substituted carbamoyl and sulfamoyl, alkoxycarbonyl, cycloalkoxycarbonyl, alkanoyloxy, ##STR8## R 3 and R 4 are independently selected from hydrogen, lower alkyl, alkenyl or aryl; n is an integer from 0-16; n 1 is an integer from 0-24, m is an integer from 0-16; m 1 is an integer from 0-24; provided that the sums of n+m and n 1 +m 1 are 16 and 24, respectively. In the definitions of the substituents (Y)n, (Y)n 1 , --(XR)m and (--X--R)m 1 these substituents are not present when n, n 1 , m and m 1 are zero, respectively. Substituents (X--R)m and (Y)n are present in compounds Ia on the peripheral carbon atoms, i.e. in positions 1, 2, 3, 4, 8, 9, 10, 11, 15, 16, 17, 18, 22, 23, 24, 25 and substituents (X-R)m 1 and (Y)n 1 are present on the peripheral carbon atoms of IIa, i.e. in positions 1, 2, 3, 4, 5, 9, 10, 11, 12, 13, 14, 18, 19, 20, 21, 22, 23, 27, 28, 29, 30, 31, 32 and 36. In a preferred embodiment of this invention the near infrared fluorescing compound is a squaraine compound of Formula III, wherein R 1 and R 2 are independently alkoxycarbonyl. In a further preferred embodiment of this invention, the near infrared fluorescing compound is a 2,3-naphthalocyanine compound of Formula II, wherein the naphthalocyanine moiety is bonded (at the 37 and 39 positions) to hydrogen, AlCl, AlOH, AlOR 5 , SICl 2 , Si(OH) 2 , Si(OR 6 ) 2 , Zn or Mg, m 1 is 0, Y is selected from hydrogen and alkyl and n 1 is 24 with Y groups representing at least four alkyl or aryl groups. In a further preferred embodiment of this invention, the near infrared fluorescing compound is a phthalocyanine compound of Formula I, wherein X is oxygen, R is aryl or alkyl, Y is hydrogen, m is 4, and n is 12; and wherein the phthalocyanine moiety is bonded (at the 29 and 31 positions) to hydrogen, AlCl, AlOH, AlOCOCF 3 , AlOR 5 , SICl 2 , Si(OH) 2 , or Si(OR 6 ) 2 , Zn or Mg. In a further preferred embodiment, the phthalocyanine and naphthalocyanine compounds are bonded to hydrogen, i.e., at the 29 and 31 positions of the phthalocyanine and the 37 and 39 position of the naphthalocyanine. In an especially preferred embodiment, the phthalocyanine, naphthalocyanine squaraine and croconic acid derivatives consist of carbon, hydrogen, and nitrogen atoms. Other examples of preferred near infrared fluorescing compounds and moieties can be found in the tables below. The term "lower alkyl" is used to represent straight or branched chain hydrocarbon radicals containing 1-6 carbons. In the terms alkyl, alkoxy, alkylthio, alkylsulfonyl, alkoxycarbonyl, alkanoyl and alkanoyloxy, the alkyl portion of the groups contain 1-20 carbons and may contain straight or branched chains. The term "cycloalkyl" is used to represent a cyclic aliphatic hydrocarbon radical containing 3-8 carbons, preferably 5 to 8 carbons and these radicals substituted by one or more groups selected from the group of alkyl, alkoxy or alkanoyloxy. The alkyl and lower alkyl portions of the previously defined groups may contain as further substituents one or more groups selected from halogen, cyano, C 1 -C 6 -alkoxy, cycloalkyl, aryl, C 1 -C 6 -alkylthiol, arylthio, aryloxy, C 1 -C 6 -alkoxycarbonyl or C 1 -C 6 -alkanoyloxy. The term "aryl" includes carbocyclic aromatic radicals containing 6-18 carbons, preferably phenyl and naphthyl, and such radicals substituted with one or more substituents selected from alkyl, alkoxy, halogen, --CH═N--alkyl, alkylthio, N(alkyl) 2 , trifluromethyl, cycloalkyl, --CH═N--C 6 H 4 --CO 2 alkyl, alkoxycarbonyl, alkanoylamino, alkylsulfonylamino, arylsulfonylamino, cycloalkylsulfonylamino, alkanoyloxy, cyano, phenyl, phenylthio and phenoxy. The term "heteroaryl" is used to represent mono or bicyclic hetero aromatic radicals containing at least one "hetero" atom selected from oxygen, sulfur and nitrogen or a combination of these atoms. Examples of suitable heteroaryl groups include: thiazolyl, benzothiazolyl, pyrazolyl, pyrrolyl, thienyl, furyl, thiadiazolyl, oxadiazolyl, benzoxazolyl, benzimidazolyl, pyridyl, pyrimidinyl and triazolyl. These heteroaryl radicals may contain the same substituents listed above as possible substituents for the aryl radicals. The term triazolyl also includes structure V and mixed isomers thereof, ##STR9## wherein R 11 is hydrogen or selected from alkyl and alkyl substituted with one or two groups selected from halogen, alkoxy, aryl, cyano, cycloalkyl, alkanoyloxy or alkoxycarbonyl. The terms "alkenyl and alkynyl" are used to denote aliphatic hydrocarbon moiety having 3-8 carbons and containing at least one carbon-carbon double bond and one carbon-carbon triple bond, respectively. The term halogen is used to include bromine, chlorine, fluorine and iodine. The term "substituted alkyl" is used to denote a straight or branched chain hydrocarbon radical containing 1-20 carbon atoms and containing as substituents 1 or 2 groups selected from halogen, cycloalkyl, cyano, C 1 -C 6 alkoxy, aryl, C 1 -C 6 alkylthio, arylthio, aryloxy, C 1 -C 6 alkoxycarbonyl, or C 1 -C 6 alkanoyloxy. The term "substituted carbamoyl" is used to denote a radical having the formula --CONR 12 R 13 , wherein R 12 and R 13 are selected from unsubstituted or substituted alkyl, alkenyl, alkynyl, cycloalkyl, aryl, heteroaryl, or R 12 and R 13 when alkyl may be combined to form a 5-8 membered ring which may be substituted with 1-4 lower alkyl groups. The term "substituted sulfamyl" is used to denote a radical having the formula --SO 2 NR 12 R 13 , wherein R 12 and R 13 are as defined above. The term "alkylene" refers to a divalent C 1 -C 20 aliphatic hydrocarbon moiety, either straight or branched-chain, and either unsubstituted or substituted with one or more groups selected from alkoxy, halogen, aryl, or aryloxy. The term "acyl" refers to a group of the formula R° C(O)--O--, wherein R° is preferably a C 1 -C 20 alkyl moiety. The term "alkyl sulfonyl" refers to a group of the formula R° SO 2 --, wherein R° is as defined for acyl. Typical alkyl groups include methyl, ethyl, propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, n-pentyl, isopentyl, neopentyl, n-hexyl, isohexyl, heptyl, octyl, nonyl, 2-ethylhexyl, decyl, undecyl, dodecyl, tetradecyl, hexadecyl, octadecyl and eicosyl. Typical cycloalkyl groups include cyclopentyl, cyclohexyl, cycloheptyl, 2,3 and 4-methylcyclohexyl, 3,4-dimethylcyclohexyl, 3,5-dimethylcyclohexyl and menthyl(2-isopropyl-5-methylcyclohexyl). Typical aryl groups include phenyl, naphthyl, 2,3 and 4-methylphenyl, 2,3 and 4-ethylphenyl, 4-isopropylphenyl, 2-n-propylphenyl, 4-n-butylphenyl, 4-sec-butylphenyl, 4-tert-butylphenyl, 2,6-diethylphenyl, 2-ethyl-6-methylphenyl, 2,4,6-trimethylphenyl, 4-n-pentylphenyl, 4-octylphenyl, 4-cyclohexylphenyl, 4-dodecylphenyl, 4-hexyloxyphenyl, 4-n-butoxyphenyl, 4-n-butoxycarbonylphenyl, 4-hexyloxycarbonylphenyl, 4-isobutyloxyphenyl, 4-hexanoyloxyphenyl and 4-(2-ethyl-hexyloxy)phenyl. Typical --X-R groups include those listed in Table 1 below. Two general routes are available for the synthesis of the NIRF compounds of Formula I. Route I involves the reaction of substituted phthalonitriles VI containing one or more leaving groups Z with one or more nucleophiles VII (A. W. Snow and J. R. Griffith, Macro-molecules, 1984, 17 (1614-1624), in the presence of a high boiling polar solvent such as N,N-dimethyl-formamide, N,N-dimethylacetamide, N-methyl-2-pyrrolidinone, tetramethylurea, and hexamethylphospho-triamide to give intermediates VIII, which are further reacted by known procedures to give compounds I directly in a one-pot process or to give the isoindoline derivatives IX, which are converted into the desired phthalocyanines I by known processes. ##STR10## Of course, the starting compounds VI may contain further substituents which are not replaced by reaction with the nucleophile. Route 2 employs similar reaction conditions, as involved in initial step of Route 1, and makes use of the reactivity of the halogen atoms in polyhalo phthalocyanines X, containing 4-16 halogen atoms attached at peripheral carbon atoms, with nucleophiles VII (see U.K. Patent No. 1,537,375 and U.S. Pat. No. 4,606,859) to give NIRF compounds I. ##STR11## In the above nucleophilic reactions utilized in Routes 1 and 2, the base, or acid binding agent, may be an alkali metal hydroxide, an alkali metal bicarbonate or an alkali metal carbonate. For example, sodium carbonate, potassium carbonate, lithium hydroxide, sodium hydroxide, sodium bicarbonate and suitable bases. The 2,3-naphthalocyanines of Formula II can be prepared by reacting 2,3-naphthalene-dicarbonitrile compounds XI to give 1,3-diiminobenz[f]-isoindolines XII, which are then converted to the naphthalocyanines of Formulae II by known procedures [J.A.C.S. 1984, 106, 7404-7410; U.S. Pat. No. 5,039,600, incorporated herein by reference; Zn. Obshch. Khim, 1972, 42(3), 696-9 (CA 77: 141469m); and Jap. Pat. 61,215,663 (CA 106:86223s)]. ##STR12## Intermediate compounds XI which contain one or more electron donating groups (--X-R) are conveniently prepared by reacting intermediate 2,3-naphthalenecarbonitriles XIII ##STR13## containing replaceable halogens with one or more nucleophiles under reaction conditions which favor nucleophilic displacements (J. Heterocyclic Chem. 1990, Vol. 27, Iss. 7, pp 2219-20). The squaraines of Formula III can be prepared by reacting the corresponding unsubstituted and substituted 1,3-dihydro-2-methylene-1,1-dimethyl-1H-benz[e]indoles with squaric acid IS. Cohen, et al., JACS, 81, 3480 (1959)]. The reactions of squaric acid are well known in the art [R. West, editor, OXOCARBONS, Academic Press, New York, 1980, pp 185-231; G. Maahs and P. Hagenberg, Angew. Chem. internat. Edit., Vol. 5 (1966), No. 10, p 888; A. H. Schmidt, Synthesis, December 1980, p, 961]. The intermediate 1,3-dihydro-2-methylene-1,1-dimethyl-H-benz[e]indoles XIV can be synthesized by known procedures [U.S. Pat. No. 5,030,708, incorporated herein by reference]. The synthetic route is illustrated as follows: ##STR14## Intermediate 1,3-dihydro-2-methylene-1,1-dimethyl-H-benz[e] indoles XIV are reacted with squaric acid XV as shown to produce the squaraines. Of course, an unsymmetrical derivative is obtained as one of the components of the mixture prepared by reacting a mixture of two or more different intermediate benz[e]indole compounds XIV with squaric acid. Croconic acid derivatives IV are prepared by the same procedure as the squaraines, except that croconic acid is used instead of squaric acid. The preferred compounds which are useful in the practice of the invention contain one or a multiplicity of hydrocarbon moieties which can impart adequate solubility in the petroleum hydrocarbons. Usually the hydrocarbon moieties contain at least one straight or branched chain C 4 -C 20 groups, which may be in combination with one or more aryl or cycloalkyl groups. In general, if only one or two hydrocarbon moieties are present the alkyl portion of the moiety should contain at least eight carbon atoms. A convenient method for introducing adequate hydrocarbon moieties into the infrared fluorophore structure is to react infrared fluorophores (FL) containing electron deficient functional groups such as carboxy, carbonyl chloride, carbalkoxy or sulfonyl chloride with hydrocarbon rich compounds which contain electron rich groups such as alcohols and amines to give the corresponding esters and amides. Or, on the contrary, one can react infrared fluorophores (FL) containing functional amines and hydroxy groups with hydrocarbon rich compounds which contain functional groups such as carboxy, carbonyl chloride, carbalkoxy or sulfonyl chloride. Preferably, the carbalkoxy groups should be lower carbalkoxy, e.g. carbomethoxy, to promote easier transesterification. Typical reactions include the following: ##STR15## wherein n is 1-8 and Z is a hydrocarbon rich moiety. Reaction 1 may be conveniently carried out by heating the infrared fluorophore which contains the carbomethoxy group(s) with excess hydrocarbon rich alcohol(s), ZH, in the presence of a transesterification catalyst such as titanium IV isopropoxides while allowing the methanol thus formed to be removed. Reactions 2, 3 and 4 are normally performed in the presence of base to facilitate completion of the reaction. Such bases include alkali metal carbonates, alkali metal bicarbonates, amines, e.g. trialkylamines and pyridine. To promote the formation of fluorophores having optimum solubility it is desirable that they be largely amorphous and to have low melting points or even be liquids. One method to accomplish this desired feature is to intentionally produce mixtures of fluorophores, preferably containing a high degree of branching in the alkyl portion of the hydrocarbon moiety. The following examples illustrate further the synthetic methods which are used in preparing the compounds which are useful in the practice of the invention. Experimental Section EXAMPLE 1 A mixture of methyl 1,1,2-trimethyl-1H-benz[e]-indole-7-carboxylate (tautomer is methyl 1,3-dihydro-2-methylene-1,1-dimethyl-1H-benz [e]indole-7-carboxylate), 2.67 g (0.01 m) (see U.S. Pat. No. 5,030,708), squaric acid (0.57 g, 0.005 m) and 2-ethoxyethanol (40 g) was heated at reflux under nitrogen for 16 hours. The reaction mixture was cooled with an ice bath and the green solid collected by filtration, washed with isopropanol and dried in air. Recrystallization from 2-ethoxyethanol (20 mL), collection of the solid by filtration, washing of the solid with isopropanol and drying gave the pure product. Mass spectrometry indicated mostly the following structure plus a small amount ##STR16## of the mono 2-ethoxyethyl ester which had been produced by transesterification. In methylene chloride an absorption maximum (A max) was observed in the visible-near infrared absorption spectrum at 690 nm (ε--214, 287). EXAMPLE 2 A mixture of methyl 1,1,2-trimethyl-1H-benz[e]-indole-7-carboxylate (tautomer is methyl 1,3-dihydro-2-methylene-1,1-dimethyl-1H-benz[e]-indole-7-carboxylate) [2.67 g (0.01 m)], croconic acid trihydrate, (0.98 g, 0.005 m) and 2-ethoxyethanol (40 g) was heated at reflux under nitrogen for 16 hours. After allowing to cool, the reaction mixture was filtered and the solid was washed with methanol and dried in air (yield 2.2 g). The product was reslurried in boiling methanol, collected by filtration, washed with methanol and dried in air (yield--2.13 g). Mass spectrometry indicated mostly the following structure: ##STR17## In methylene chloride an absorption maximum (λ max) was observed in the visible--near infrared absorption spectrum at 816 nm. EXAMPLE 3 A mixture of methyl 1,1,2-trimethyl-1H-benz[e]-indole-7-carboxylate (tautomer is methyl 1,3-dihydro-2-methylene-1,1-dimethyl-1H-benz[e]-indole-7-carboxylate) [2.67 g (0.01 m)], squaric acid (0.57 g, 0.005 m), 2-ethylhexanol (30 g) and 2 drops of titanium IV isopropoxide was heated at reflux under nitrogen for 6 hours. The excess alcohol was removed by heating on a steam bath under vacuum. A solid was produced by treating the residue with hexane (some solubility) and was collected by filtration, washed with petroleum ether and dried in air (yield 2.92 g). Mass spectrometry and proton NMR supported the following structure: ##STR18## In toluene, an absorption maximum at 698 nm was observed in the near infrared absorption spectrum (E-192,197). EXAMPLE 4 A 300 mL 3-neck round-bottom flask was equipped with a magnetic stirrer, thermometer and gas inlet tube. Methanol (50 mL) was added followed by sodium metal (0.66 g, 0,029 mole) with stirring to facilitate reaction and solution, with a slow nitrogen purge applied. To this solution was added 12.54 g (0.058 mole) of 4-phenoxyphthalonitrile (A. W. Snow and J. R. Griffith, Macromolecules, 1984, 17, 1614-24), followed by additional methanol (50 mL). Anhydrous ammonia was bubbled in under the surface, giving an exotherm to 45° C. and total solution. The ammonia addition was continued until no more starting material was evident by thin-layer chromatography. The solution was clarified by filtering through a pad of Dicalite filter aid which had a small layer of charcoal on it and the filtrate drowned into water. The oily product layer thus produced was washed by decantation with 500 mL portions of water (4-5 times or until pH reached about 7-8). After the final wash water was decanted off, methanol was added to dissolve the product, which crystallized upon stirring overnight at room temperature. After being collected by filtration, the greenish-yellow solid was washed with methylene chloride and dried in air. The yield was 13.75 g, 91.1% of the theoretical yield. Mass spectrometry showed the product to consist largely of the desired 5-phenoxy-1,3-diiminoisoindoline. EXAMPLE 5 A mixture of 5-phenoxy-1,3-diiminoisoindoline (3.68 g, 0.016 m) (from Example 4), 1,2,3,4-tetrahydro-aphthalene (20 mL) and tri-n-butylamine (10 mL) was stirred under a nitrogen sweep. Aluminum chloride (3.19 g, 0.024 m) was added to give a slurry. After the reaction mixture was heated at about 180° C. for 4 hours, it was allowed to cool to room temperature and diluted with methanol to enhance solubility to facilitate transfer into about 500 mL of ice-water mixture containing 10 mL HCl. The somewhat "greasy" solid product was collected by filtration and washed with dilute HCl. The filter cake was washed on the filter with cyclohexane and finally washed thoroughly with ethyl acetate and dried in air. Mass Spectrometry indicated good quality 2(3), 9(10), 16(17), 23(24)-tetraphenoxy-Pc-Al-Cl (Pc=phthalocyanine moiety) having the desired molecular weight of 942 (1.56 g, 41.4% of the theoretical yield). EXAMPLE 6 A portion (110 mg) of the tetraphenoxy-chloroluminumphthalo-cyanine of Example 5 was dissolved in trifluoroacetic acid (10 mL) and allowed to evaporate at room temperature. As evidenced by mass spectrometry, the residual product was mostly 2(3), 9(10), 16(17), 23(24)-tetraphenoxy-Pc-AlOCOCF 3 , molecular weight 1020. In methylene chloride, absorption maxima were observed at 696 nm (ε--126,170), 629 nm (ε--26,697), 341 nm (ε--58,872) and 292 nm (ε--30,600) in the ultraviolet, visible, near-infrared absorption spectra. EXAMPLE 7 A reaction mixture of tetraphenoxy-chloroaluminum phthalocyanine (0.94 g) of Example 5, dimethyl-3-ydroxyisophthalate (0.24 g) and pyridine (20 g) was heated at reflux for 24 hours and allowed to cool to room temperature. Isopropanol (20 mL) was added and then by the addition of water, the phthalocyanine (Pc) product was precipitated, [2(3), 9(10), 16(17), 23(24)-tetraphenoxy-pc-AlOC 6 H 3 -3,5-di--CO 2 CH 3 ], which was collected by filtration, washed with water and dried in air (yield--0.90 g). In methylene chloride, absorption maxima were observed at 696 nm (104,585), 626 nm (32,882) and 343 nm (64,090) in the ultraviolet, visible and near infrared absorption spectra. EXAMPLE 8 A mixture of 5-phenoxy-1,3-diiminoisoindoline (3.68 g, 0.016 mole), silicon tetrachloride (4.0 g, 0.024 mole) 1,2,3,4-tetrahydronaphthalene (20 mL) and tri-n-butylamine (10 mL) was heated under nitrogen at about 200° C. for 40 minutes, allowed to stir overnight at room temperature and reheated to 180° C. and held for about 2.0 hours. After cooling to room temperature, the reaction mixture was diluted with 30 mL of methanol, filtered, and the collected solid washed with methanol and dried in air (yield--2.71 g, 69.3% of the theoretical yield). Mass spectrometry supported the structure: 2(3), 9(10), 16(17), 23(24)-tetra-phenoxy-Pc--Si-(Cl) 2 . EXAMPLE 9 A mixture of the tetraphenoxy-dichlorosiliconphthalocyanine (0.49 g) of Example 8, methyl 4-hydroxy-benzoate (0.16 g) and pyridine (5 g) was heated at reflux for 3 hours under nitrogen. To the cooled reaction mixture were added isopropanol (20 mL) and then water (20 mL) with stirring. The product was collected by filtration, washed with water and dried in air. Mass spectrometry supports the structure: 2(3), 9(10), 16(17), 23(24)-tetraphenoxy-pc-Si-(OC 6 H 4 --4--CO 2 CH 3 ) 2 . EXAMPLE 10 A mixture of silicon phthalocyanine dichloride (0.2 g) was dissolved in trifluoroacetic acid (10 mL) and the reaction mixture allowed to stand in a hood in an evaporating dish until all the excess trifluoroacetic acid had evaporated. Absorption maxima were observed at 691 nm (ε--168,645), 659 nm (ε--21,596), 622 nm (ε--4,789), 356 nm (ε--50,090) and 334 nm (ε--44,608) in the ultraviolet-visible-near infrared absorption spectra. The product was assumed to be silicon phthalocyanine trifluroacetate [Pc-Si (OCOCF 3 ) 2 ]. EXAMPLE 11 A reaction mixture of Nc-Si(OH) 2 (1.5 g) (J.A.C.S. 1984, 106, 7404-7410), pyridine (150 mL) and chloro dimethylphenylsilane (10 mL) was heated at reflux for 5 hours and then allowed to cool. Some insolubles were filtered off and the filtrate stripped on a rotary evaporator under vacuum. Pentane (300 mL) was added to the residue to produce a solid upon stirring which was collected by filtration, washed with 50/50 acetone/water, then with pentane and dried in air. The solid (1.9 g) was reslurried in hot pentane (300 mL) and filtered hot. The solid thus obtained was washed with pentane and air dried (yield--1.5 g). Mass spectrometry supported the following structure Nc-Si[O-si (CH 3 ) 2 C 6 H 5 ] 2 . EXAMPLE 12 A mixture of 5-phenoxy-1,3-diminoiosindoline (11.04 g, 0,047 m), tetrahydronaphthalene (60 mL), and tri-n-butyl amine (30.0 mL) was stirred. Silicon tetra-chloride (12.0 g, 0.071 m) was then added and the reaction mixture was heated slowly to reflux and held for 4 hours. After allowing to cool, the reaction mixture was diluted with an equal volume of methanol. The product, 2(3), 9(10), 16(17), 23(24) tetraphenoxy-PcSiCl 2 was collected by filtration, washed with methanol, then washed with water and dried in air. The yield of product was 7.7 g. EXAMPLE 13 A portion (7.0 g, 0.0072 m) of the product of Example 11, methyl 4-hydroxybenzoate (2.4 g, 0.016 m) and pyridine (150 mL) were mixed and heated at reflux with stirring for 20 hours. The reaction mixture was cooled and then drowned into 500 mL water. Added about 50 mL of saturated sodium chloride solution with stirring. The product was collected by filtration, washed with water and dried in air (yield--7.1 g). Mass spectrometry confirmed the product to be the desired product [2(3), 9(10), 16(17), 23(24) tetraphenoxy-PcSi-(OC 6 H 4 -4--CO 2 CH 2 ) 2 ]. Absorption maxima were obtained at 649 nm and 691 nm in the light absorption spectrum in methylene chloride. EXAMPLE 14 A mixture of 3-phenylnaphthalene-2,3-dicarboxylic acid anhydride (6.26 g, 0.023), urea (45.0 g), ammonium molybdate (0.10 g) and aluminum chloride (0.90 g, 0.006 m) was heated under nitrogen at about 250° C. with stirring for 2.0 hours. Heat was removed and the dark brownish-black solid transferred into boiling water with stirring. The product was collected by filtration, reslurried in dilute hydrochloric acid, filtered, reslurried in dilute ammonium hydroxide, filtered, reslurried in hot water and finally filtered, washed with water and dried in air (yield--5.0 g). The product was presumed to be 5(36), 9(14), 18(23), 27(32) tetraphenyl-NcAlCl (Nc=naphthalocyanine moiety). EXAMPLE 15 A mixture of 3,6-di-n-butoxy phthalonitrile (2.50 g, 0.0092 m), urea (20.0 g), ammonium molybdate (0.1 g) and aluminum chloride (0.41 g, 0.003 m) was heated under nitrogen with stirring at 250° C. in a Belmont metal bath for 2.0 hours. The dark solid was removed, pulverized and then added to a dilute HCl solution and stirred. The product was then collected by filtration, reslurried in dilute ammonium hydroxide, filtered, washed with water and dried in air. The product was presumed to be 1,4,8,11,15,18,22,25-octa-n-butoxy-PcAlCl. EXAMPLE 16 A mixture of 6-t-butyl-2,3-dicyanonaphthalene (23.4, 0.10 m), aluminum chloride (3.5 g) and urea (23.0 g) was heated at 218°-220° C. for 1.0 hour in a Belmont metal bath with stirring. The reaction mixture was allowed to cool and the solid was pulverized using a mortar and pestle and then slurried in 10% NaOH, collected by filtration, washed with methanol and dried in air (yield 10.3 g). Based on mass spectrometry, it was concluded that the product was a mixture of 2(3), 11(12), 20(21), 29(30)-tetra-t-butyl-NcAlCl and 2(3), 11(12), 20(21), 29(30)-tetra-t-butyl-NcAlOH. EXAMPLE 17 A mixture of 3-[2-(carbo-n-pentoxy)phenylthio]-phthalonitrile (7.0 g, 0.02 m), urea (28.6 g, 0.47 m) and aluminum chloride (0.713 g, 0.0053 m) was stirred in a Belmont metal bath (230° C.). The reddish melt was stirred slowly until homogeneous, then rapidly at about 215°-225° C. for 10 minutes. Stirring and heating were continued under a stream of N 2 for about 1.25 hours. The reaction flask was removed from the metal bath and allowed to cool. The solid was removed from the flask, placed in conc. HCl, ground to a good slurry in a mortar and pestle, filtered and washed with boiling water. Finally, the dark green solid was placed in fresh conc. HCl, the mixture boiled and then the solid was collected by filtration, washed with hot water and dried in air. The product, 1(4), 8(11), 15(18), 22(25)-tetra[2-carbo-n-pentoxy)phenylthio]-PcAlCl, when dissolved in N,N-dimethylformamide had a maximum absorption at 714 nm in the light absorption spectrum. EXAMPLE 18 A mixture of aluminum phthalocyanine chloride (5.0 g, 0.0087 m), dimethyl 5-hydroxyisophthalate (1.83 g, 0.0087 m) and pyridine (25 mL) was heated and stirred at reflux for about 18 hours under nitrogen and then after cooling was drowned into water (500 mL). The green solid was collected by filtration, washed with water (1 l) and air dried. The product, PcAlOC 6 H 3 -3,5-diCO 2 CH 3 , had an absorption maximum at 675 nm (ε--198,481) in the light absorption spectrum in N,N-dimethylformamide. EXAMPLE 19 A mixture of 4-phenylthiophthalonitrile (2.36 g, 0.01 m), aluminum chloride (0.35 g, 0.0026 m), ammonium molybdate (0.10 g) and urea (40.0 g) was placed in a flask and heated in a Belmont metal bath at about 200° C. with stirring for 2.5 hours at about 245° C. The flask was removed from the metal bath and allowed to cool. The solid was ground in a mortar and pestle, added to hot water, collected by filtration, washed with hot water, 5% HCl, dilute NH 4 OH, hot water, 10% HCl, warm water and air dried (yield 2.50 g, 99.4% of the theoretical yield). An absorption maximum was observed at 701 nm in the light absorption spectrum of the product, 2(3), 9(10), 16(17), 23(24)-tetraphenylthio-PcAlCl, when dissolved in N,N-dimethylformamide. EXAMPLE 20 A mixture of a portion (2.33 g, 0.0023 m) of the product of Example 19, dimethyl 5-hydroxyisophthalate (0.49 g, 0.0023 m) and pyridine (25 g) was heated and stirred at reflux under N 2 for 16 hours and then allowed to cool. The product [2(3), 9(10), 16(17), 23(24)-tetraphenylthio-AlOC 6 H 3 -3,5-diCO 2 CH 3 ] was isolated by drowning into water (500 mL) and collecting by filtration and was then washed with water, acetone and methanol and dried in air. Attempts to obtain light absorption spectrum failed because of insolubility of the product. EXAMPLE 21 A mixture of aluminum naphthalocyanine chloride (0.98 g, 0.00126 m) (Aldrich Chemical Co.), dimethyl 5-hydroxyisophthalate (0.21 g, 0.001 m), potassium carbonate (0.09 g) and dimethyl sulfoxide (23 g) was heated and stirred under N 2 , at 95°-100° C. for about 8 hours. Very little solution of reactants seemed to have occurred. Added pyridine (23 mL) and heated at reflux under N 2 for about 96 hours (over the weekend). The green reaction mixture was allowed to cool and then drowned in water. The product (NcAl-OC 6 H 3 -3,5-di-CO 2 CH 3 ) was collected by filtration, washed with water, reslurried in water, collected again by filtration, washed with water and dried in air (yield--0.94 g, 79.0% of the theoretical yield. An absorption maximum at 779 nm was observed in the light absorption spectrum in dimethyl sulfoxide. EXAMPLE 22 A mixture of silicon naphthalocyanine dichloride (0.20 g, 2.46×10 -4 m), methyl 4-hydroxybenzoate (0.075 g, 4.93×10 -4 m), dimethyl sulfoxide (11.4 g) and pyridine (10.5 g) was heated and stirred under N 2 at reflux for about 64 hours. The reaction mixture was drowned into ice water mixture and the product [NcSi(OC 6 H 4 -4---CO 2 CH 3 ) 2 ] was collected by filtration, washed with water and dried in air. An attempt to obtain the absorption maximum in dimethyl sulfoxide (very slightly soluble) gave an apparent maximum at 773 nm in the light absorption spectrum. EXAMPLE 23 A portion (2.0 g) of the product of Example 16 was added to conc. HCl (200 mL) and the mixture refluxed for 24.0 hours. The product 2(3), 11(12), 20(21), 29(30)-tetra-t-butylNcAlCl, was collected by filtration, washed with conc. HCl, washed with water and dried in air. An absorption maximum at 779 nm was observed in the light absorption spectrum in N,N-dimethylformamide. EXAMPLE 24 A mixture of 3-phenoxyphthalonitrile (4.4 g, 0.02 m), aluminum chloride (0.8 g, 0.005 m) was placed in a Belmont metal bath at 250° C. and heated with stirring for 30 minutes under a nitrogen sweep. The reaction mixture was allowed to cool and the solid product was ground using a mortar and pestle and then slurried in hot water (500 mL) with stirring. After being collected by filtration, the product [1(4), 8(11), 15(18), 22(25)-tetraphenoxy-PcAlCl] was washed with boiling water (1 l), washed with cyclohexane, washed with n-hexane and dried in air (yield--4.3 g, 91.3% of the theoretical yield). An absorption maximum was observed at 700 nm in the light absorption spectrum in N,N-dimethylformamide. EXAMPLE 25 A portion (2.0 g, 0.002 m) of the product of Example 24, dimethyl 5-hydroxyisophthalate (0.5 g, 0.002 m) and pyridine (100 mL) were mixed and heated with stirring at reflux for 24 hours. The reaction mixture was drowned into water and the solid was collected by filtration, washed with cyclohexane, washed with n-hexane and dried in air (yield 2.1 g, 94.2% of the theoretical yield). The product [1(4), 8(11), 15(18), 22(25)-tetraphenoxy-PcAlOC 6 H 3 -3,5-diCO 2 CH 3 ] had an absorption maximum at 699 nm in the light absorption spectrum in N,N-dimethylformamide. EXAMPLE 26 A mixture of 3-phenylthiophthalonitrile (11.8 g, 0.05 m) aluminum chloride (1.8 g, 0.014 m) was heated in a Belmont metal bath under a nitrogen sweep at about 250° C. for 1 hour. The reaction mixture was allowed to cool and the solid was ground in a mortar and pestle and then slurried by stirring in a warm 6% HCl aqueous solution. The product [1(4), 8(11), 15(18), 22(25)-tetraphenylthio-PcAlCl] was collected by filtration washed with warm water, washed with 6% HCl solution, washed with warm water and dried in air. Field desorption mass spectrometry showed a molecular ion of 1006, which supports the expected structure. An absorption maximum at 724 nm (ε--114,724) was observed in the light absorption spectrum in N,N-dimethyl-formamide. EXAMPLE 27 A portion (5.03 g 0.005 m) of the product of Example 26, dimethyl 5-hydroxyisophthalate (1.05 g, 0.005 m) and pyridine (250 mL) were mixed and heated at reflux for 48 hours. The cooled reaction mixture was then drowned into water and the solid product was washed with warm water and dried in air (yield--5.4 g). A portion (1.5 g) of the product was dissolved in tetrahydrofuran (25.0 mL) and the solution placed on a column of activated aluminum oxide (150 mesh) (Aldrich Chem. Co.) and then eluted with methylene chloride to remove a fast moving band. The remaining product was eluted with methanol and then the methanol was removed by evaporation (yield--0.72 g). Field desorption mass spectrometry supported the desired product, 1(4), 8(11), 15(18), 22(25)-tetraphenylthio-pcAlOC 6 H 3 -3,5-diCO 2 CH 3 . An absorption maximum was observed at 729 nm (ε--128,526) in the light absorption spectrum of the chromatographed product in N,N-dimethylformamide. EXAMPLE 28 A mixture of 6-t-butyl-1,3-diiminobenz(b) isoindoline (15.0 g, 0.06 m) silicon tetrachloride (10.8 mL), tetrahydronaphthalene (100.0 mL) and tributylamine (40.0 mL) was heated to reflux over a 1.0 hour period. After being refluxed for 3.0 hours, the reaction mixture was allowed to cool and then was treated with isopropanol (400 mL). The mixture was then drowned into water (1.0 l) and the solid [2(3), 11(12), 20(21), 29(30)-tetra-t-butyl-NcSiCl 2 ] was collected by filtration, washed with water and dried in air (yield--12.0 g). Absorption maxima were observed at 777 nm and 835 nm in the light absorption spectrum in N,N-dimethylformamide. EXAMPLE 29 A mixture of 3-nitrophthalonitrile (8.65 g, 0.05 m), aluminum chloride (1.67 g, 0.0125 m) was heated in a Belmont metal bath under a nitrogen sweep at about 250° C. for 1 hour. The reaction mixture was allowed to cool and the solid was ground in a mortar and pestle and then slurried in a warm 6% HCl aqueous solution. The product [1(4), 8(11), 15(18), 22(25)-tetranitro-PcAlCl] was collected by filtration, washed with warm water, washed with 6% HCl solution, washed with warm water and dried in air. EXAMPLE 30 A mixture of 2-3-dicyano-5-nitronaphthalene (8.9 g, 0.04 m), aluminum chloride (1.33 g, 0.01 m) was heated in a Belmont metal bath under a nitrogecn sweep at about 250° C. for 1 hour. The reaction mixture was allowed to cool and the solid was ground in a mortar and pestle and then slurried in a warm 6% HCl aqueous solution. The product [1(4), 10(13), 19(22), 29(31)-tetranitro-NcAlCl] was collected by filtration, washed with warm water, washed with 6% HCl solution, washed with warm water and dried in air. EXAMPLE 31 A stock solution of the infrared fluorophore of Example 3 in toluene was prepared by dissolving 0.0089 g of fluorophore in 100 g of toluene (0.089 g/L, 890×10 -4 g/L). Dilutions of 1/25, 1/100, 1/200 and 1/1000 to give concentrations of 356×10 -5 g/L, 890×10 -6 g/L, 445×10 -6 g/L and 890×10 -7 g/L (8.9×10 -5 g/L) were made. At the lower concentration levels color was invisible to the eye. When exposed to light generated by a laser diode at 670 nm all of the samples had detectable fluorescence with a detector designed to detect infrared radiation having wavelengths in the 700-720 nm range. EXAMPLE 32 The stock solution of Example 31 was diluted at the ratio of 1/25, 1/100, 1/200 and 1/1000 using premium grade gasoline to produce concentrations of 356×10 -5 g/L, 890×10 -6 g/L, 445×10 -6 g/L and 890×10 -7 g/L (8.9×10 -5 g/L). No color was observable in the samples having the lower concentrations. When exposed to light generated by a laser diode at 670 nm all of the samples had detectable fluorescence with a detector designed to detect infrared radiation having wavelengths in the 700-720 nm range. Upon standing several days none of the infrared fluorophores had settled or crystallized out even in the higher concentrations. TABLE 1__________________________________________________________________________EXEMPLARY XR GROUPSXR XR__________________________________________________________________________OCH.sub.2 CH(CH.sub.3).sub.2 ##STR19##OCH.sub.4 H.sub.9 -n ##STR20##OC(CH.sub.3).sub.3 ##STR21##OC.sub.12 H.sub.25 -n ##STR22##SCH.sub.2 CH(C.sub.2 H.sub.5)C.sub.4 H.sub.9 -n ##STR23##S(CH.sub.2).sub.12 OCOCH.sub.3 ##STR24##SC.sub.8 H.sub.17 -n ##STR25##OCH.sub.2 CH(C.sub.2 H.sub.5)C.sub.4 H.sub.9 -n ##STR26##OCH.sub.2 CHCH.sub.2 ##STR27##OCH.sub.2 CHCH.sub.2 ##STR28##SCH.sub.2 C.sub.6 H.sub.5 ##STR29##SCH.sub.2 CH(OCOC.sub.4 H.sub.9 -n)CH.sub.2 OCOC.sub.4 H.sub.9 -n OCH.sub.2 C.sub.6 H.sub.4 -4-COO(CH.sub.2).sub.6 CH.sub.3OCH.sub.2 C CH OC.sub.6 H.sub.4 -4-CH.sub.2 COO(CH.sub.2).sub.7 CH.sub.3N(C.sub.4 H.sub.9 -n).sub.2 OCH.sub.2 CH.sub.2 CO.sub.2 C.sub.4 H.sub.9 -nNHC.sub.6 H.sub.4 -4-C(CH.sub.3).sub.3 OCH.sub.2 CH.sub.2 OCOCH.sub.2 CH(C.sub.2 H.sub.5)C .sub.4 H.sub.9 -nN(C.sub.4 H.sub.9 -n)C.sub.6 H.sub.5 OC.sub.6 H.sub.4 -4-OCH.sub.2 CH.sub.3N[C.sub.2 H.sub.4 OCO(CH.sub.2).sub.4 CH.sub.3 ].sub.2 OC.sub.6 H.sub.4 -4-OCH.sub.2 CH.sub.2 OCOC.sub.4 H.sub.9 -nNHC.sub.6 H.sub.11 ##STR30##N(C.sub.4 H.sub.9 -n)C.sub.6 H.sub.11 ##STR31## ##STR32##OC.sub.6 H.sub.5 O(CH.sub.2 CH.sub.2 O).sub.2 COC.sub.3 H.sub.7 -nOC.sub.6 H.sub.4 -4-COO(CH.sub.2).sub.12 CH.sub.3 S(CH.sub.2 CH.sub.2 O).sub.2 COC.sub.4 H.sub.9 -nSC.sub.6 H.sub.4 -4-COO(CH.sub.2).sub.17 CH.sub.3 O(CH.sub.2 CH.sub.2 O).sub.4 COCH.sub.2 CH(C.sub.2 H.sub.5)C.sub.4 H.sub.9 -nOC.sub.6 H.sub.3 -3,5-diCOO(CH.sub.2).sub.7 CH.sub.3 O(CH.sub.2 CH.sub.2 O).sub.3 CH.sub.3OC.sub.6 H.sub.3 -3,5-diCO.sub.2 (CH.sub.2).sub.5 CH.sub.3 O(CH.sub.2 CH.sub.2 O).sub.2 C.sub.6 H.sub.5SC.sub.6 H.sub.4 -2-COOC.sub.4 H.sub.9 -n NH(CH.sub.2 CH.sub.2 O).sub.2 CO(CH.sub.2).sub.11 CH.sub.3SC.sub.6 H.sub.4 -3-CO.sub.2 CH.sub.2 CH(CH.sub.3).sub.2OC.sub.6 H.sub.4 -4-C.sub.2 H.sub.4 OCOC.sub.6 H.sub.11__________________________________________________________________________ TABLE 2 SQUARAINE COMPOUNDS ##STR33## EX. NO. R.sub.1, R.sub.2 R.sub.3, R.sub.4 R', R" 33 7-CO.sub.2 (CH.sub.2).sub.3 CH.sub.3 CH.sub.3 CH.sub.3 34 7-CO.sub.2 C.sub.2 H.sub.5 C.sub.6 H.sub.5 CH.sub.3 35 7-CO.sub.2 (C.sub.6 H.sub.4 -4-CH(CH.sub.3).sub.2 C.sub.6 H.sub.4 -4-CH.sub.3 CH.sub.3 36 7-CONHCH.sub.2 CH(C.sub.2 H.sub.5)C.sub.4 H.sub.9 -n H CH.sub.3 37 7-CONHC.sub.2 H.sub.4 OCO(CH.sub.2).sub.6 CH.sub.3 H CH.sub.3 38 7-CON(CH.sub.3)C.sub.2 H.sub.4 OCOCH.sub.2 CH(CH.sub.3).sub.2 CH.sub.3 CH.sub.3 39 7-CON(CH.sub.3)C.sub.6 H.sub.11 H CH.sub.3 40 7-CONHC.sub.6 H.sub.11 C.sub.4 H.sub.9 -n CH.sub.3,CH.sub.2 CH.sub.3 41 7-CONHC.sub.6 H.sub.4 -4-C.sub.6 H.sub.11 H CH.sub.2 CH.sub.3,CH.sub.2 CH.sub.3 42 7-CONHCH.sub.2 C.sub.6 H.sub.10 -4-CH.sub.2 OH CH.sub.3 CH.sub.3,CH.sub.2 CH(CH.sub.3).sub.2 43 7-CONHC.sub.6 H.sub.4 -4-CO.sub.2 CH.sub.3 H CH.sub.3,CH.sub.2 CH.sub.2 CH(CH.sub.3).sub.2 44 7-SO.sub.2 N(CH.sub.3)(CH.sub.2).sub.6 CH.sub.3 H CH.sub.3,CH(CH.sub.3).sub.2 45 7-SO.sub.2 N(C.sub.4 H.sub.9 -n).sub.2 CH.sub.3 CH.sub.2 CH(CH.sub.3).sub.2,CH.sub.2 CH.sub.3 46 7-SO.sub.2 N(CH.sub.3)C.sub.6 H.sub.11 CH.sub.3 (CH.sub.2).sub.5 CH.sub.3,(CH.sub.2).sub.5 CH.sub.3 47 ##STR34## H CH.sub.3 48 ##STR35## H CH.sub.3 49 ##STR36## H CH.sub.3 50 7-SO.sub.2 NHCH.sub.2 C(CH.sub.3).sub.2 CH.sub.3 C.sub.6 H.sub.5 CH.sub.3 51 7-SO.sub.2 NH(CH.sub.2).sub.17 CH.sub.3 H CH.sub.3 52 7-SO.sub.2 NHC.sub.6 H.sub.4 -3-CO.sub.2 (CH.sub.2).sub.6 CH.sub.3 H CH.sub.3 53 7-SO.sub.2 NHC.sub.6 H.sub.4 -4-(CH.sub.2).sub.11 CH.sub.3 H CH.sub.3 54 7-SO.sub.2 NHC.sub.6 H.sub.4 -3-CH.sub.2 OCO(CH.sub.2).sub.10 CH.sub.3 CH.sub.3 CH.sub.3 55 7-SO.sub.2 NHC.sub.6 H.sub.10 -4-CH.sub.3 CH.sub.2 CHCH.sub.2 CH.sub.3 56 7-(CH.sub.2).sub.8 CH.sub.3 H CH.sub.3 57 7-OC.sub.6 H.sub.6 -4-OCH.sub.2 CH(CH.sub.3).sub.2 H CH.sub.3 58 7-(OC.sub.2 H.sub.4).sub.3 OCH.sub.3 H CH.sub.3 59 7-S(CH.sub.2).sub.9 CH.sub.3 H CH.sub.3 60 7-SC.sub.6 H.sub.4 -4-C.sub.6 H.sub.11 H CH.sub.3 61 8-(CH.sub.2).sub.3 CH.sub.3 CH.sub.3 CH.sub.3 62 8-OCH.sub.2 CH(C.sub.2 H.sub.5)C.sub.4 H.sub.9 -n H CH.sub.3 63 8-O(CH.sub.2).sub.11 CH.sub.3 H CH.sub.3 64 8-OCO(CH.sub.2).sub.6 CH.sub.3 H CH.sub.3 65 7-C.sub.6 H.sub.11 H CH.sub.3 66 7-COOC(CH.sub.3).sub.3 H CH.sub.3 67 7-CO.sub.2 (CH.sub.2).sub.3 CH(CH.sub.3).sub.2 H CH.sub.3 68 7-CO.sub.2 (CH.sub.2).sub.2 CH(CH.sub.3).sub.2 H CH.sub.3 69 7-CH.sub.2 CH(CH.sub.3)CH.sub.2 C(CH.sub.3).sub.2 CH.sub.3 H CH.sub.3 70 ##STR37## C.sub.6 H.sub.5 CH.sub.3 71 7-SO.sub.2 C.sub.6 H.sub.4 -4-O(CH.sub.2).sub.3 CH(CH.sub.3).sub.2 H CH.sub.3 72 7-SO.sub.2 (CH.sub.2).sub.2 CH(CH.sub.3)CH.sub.2 CH.sub.3 H CH.sub.3 73 7-SO.sub.2 (CH.sub.2).sub.13 CH.sub.3 H CH.sub.3 74 7-SO.sub.2 C.sub.6 H.sub.4 -3-CO.sub.2 (CH.sub.2).sub.11 CH.sub.3 H CH.sub.3 75 ##STR38## H CH.sub.3 76 ##STR39## H CH.sub.3 77 7-NHSO.sub.2 (CH.sub.2).sub.11 CH.sub.3 CH.sub.3 CH.sub.3 78 7-NHSO.sub.2 C.sub.6 H.sub.4 -4-CH.sub.2 CH.sub.3 H CH.sub.3 79 7-NHSO.sub.2 C.sub.6 H.sub.11 H CH.sub.3 80 7-N(C.sub.6 H.sub.11)SO.sub.2 (CH.sub.2).sub.5 CH.sub.3 H CH.sub.3 81 7-Sn(CH.sub.3).sub.3 CH.sub.3 CH.sub.3 82 7-Sn(OCH.sub.2 CH.sub.3).sub.3 H CH.sub.3 83 7-Si(CH.sub.3).sub.2 C.sub.6 H.sub.5 H CH.sub.3 84 7-Si(OC.sub.4 H.sub.9 -n).sub.3 H CH.sub.3 85 7-Si[OCH.sub.2 C(CH.sub.3).sub.3 ].sub.3 H CH.sub.3 TABLE 3__________________________________________________________________________PHTHALOCYANINE COMPOUNDS(Pc = PHTHALOCYANINE NUCLEUS)EX.NO. COMPOUND__________________________________________________________________________86 1(4), 8(11), 15(18), 22(25)-Tetra[4(2-ethylhexyloxycarbonyl)phenylthio] PcH.sub.287 2(3), 9(10), 16(17), 23(24)-Tetraphenoxy-PcAl--OC.sub.6 H.sub.4 -4-CO.sub.2 CH.sub.2 CH(C.sub.2 H.sub.5)C.sub.4 H.sub.9 -n88 2(3), 9(10), 16(17), 23(24)-Tetraphenoxy-PcAl--SC.sub.6 H.sub.4 -2-CO.sub.2 (CH.sub.2).sub.3 CH(CH.sub.3).sub.289 2(3), 9(10), 16(17), 23(24)-Tetraphenoxy-PcAl--S--C.sub.6 H.sub.4 -2-CO.sub.2 C.sub.4 H.sub.9 -n90 2(3), 9(10), 16(17), 23(24)-Tetraphenoxy-PcAlOC.sub.6 H.sub.4 -4-C.sub. 6 H.sub.1191 2(3), 9(10), 16(17), 23(24)-Tetra-(4-n-butoxyphenoxy)-PcAlOCOCF.sub.392 2(3), 9(10), 16(17), 23(24)-Tetra-(4-nonylphenoxy)PcH.sub.293 2(3), 9(10), 16(17), 23(24)-Tetra-(4-t-butylphenylthio)-PcH.sub.294 2(3), 9(10), 16(17), 23(24)-Tetra-(4-isoamylphenylthio)-PcZn95 2(3), 9(10), 16(17), 23(24)-Tetra-(4-n-hexylphenoxy)-PcSiCl.sub.296 2(3), 9(10), 16(17), 23(24)-Tetra-[4-(2-ethylhexyloxycarbonyl)-phenylth io]PcH.sub.297 2(3), 9(10), 16(17), 23(24)-Tetra-(4-cyclohexylphenoxy)-PCSi(OCH.sub.2 CH.sub.2 OC.sub.4 H.sub.9 -n).sub.298 2(3), 9(10), 16(17), 23(24)-Tetra-(4-dodecylphenoxy)-PcSi(OC.sub.4 H.sub.9 -n).sub.299 2(3), 9(10), 16(17), 23(24)-Tetra-(4-undecylphenoxy)-PcSi(OCOCH.sub.3). sub.2100 2(3), 9(10), 16(17), 23(24)-Tetra-(4-tetradecylphenoxy)-PcH.sub.2101 2(3), 9(10), 16(17), 23(24)-Tetra-(4-octadecylphenoxy)-PcMg102 2(3), 9(10), 16(17), 23(24)-Tetra-(dodecylthio)-PcH.sub.2103 2(3), 9(10), 16(17), 23(24)-Tetra-(4-carbodecyloxyphenoxy)-PcH.sub.2104 2(3), 9(10), 16(17), 23(24)-Tetra-(2(carbononyloxyphenylthio)-PcSi(OH). sub.2105 2(3), 9(10), 16(17), 23(24)-Tetrallyloxy-PcAlCl106 2(3), 9(10), 16(17), 23(24)-Tetra(2-ethylhexylamino)PcH.sub.2107 2(3), 9(10), 16(17), 23(24)-Tetracyclohexyloxy-PcSi[OC(C.sub.6 H.sub.5).sub.3 ]1.sub.2108 2(3), 9(10), 16(17), 23(24)-Tetra(6-t-butylbenzothiazol-2-ylthio)-PcAlC l109 2(3), 9(10), 16(17), 23(24)-Tetra(6-isopropylbenzoxazol-2-ylthio)PcAlOC OCF.sub.3110 2(3), 9(10), 16(17), 23(24)-Tetra(5-n-hexyl-1,3,4-thiadiazol-2-ylthio)P cAlCl111 2(3), 9(10), 16(17), 23(24)-Tetra(4,6-di-methyl-2-pyridylthio)-PcSi(OC. sub.6 H.sub.4 -4-t-butyl).sub.2112 2(3), 9(10), 16(17), 23(24)-Tetra(4-cyclohexylphenyl)telluro-PcSi(OH.su b.2)113 2(3), 9(10), 16(17), 23(24)-Tetra(4-dodecylphenyl)seleno-PcAlCl114 2(3), 9(10), 16(17), 23 (24)-Tetra-n-octylthio-PcSi(OC.sub.6 H.sub.4 -4-F).sub.2115 2(3), 9(10), 16(17), 23(24)-Tetra-(6-t-butyl-2-naphthylthio)-PcAlOH116 2(3), 9(10), 16(17), 23(24)-Tetradioctylamino-PcAlOCOCF.sub.3117 2(3), 9(10), 16(17), 23(24)-Tetrapiperidino-PcAlOH118 2(3), 9(10), 16(17), 23(24)-Tetratriazol-3-ylthio-PcSiCl.sub.2119 2(3), 9(10), 16(17), 23(24)-Tetratriazol-3-ylthio-PcH.sub.2120 2(3), 9(10), 16(17), 23(24)-Tetratriazol-3-ylthio-PcSi(OH.sub.)2121 2(3), 9(10), 16(17), 23(24)-Tetra[(2-ethylhexyloxy)anilino]-PcH.sub.2122 2(3), 9(10), 16(17), 23(24)-Tetra(4-dodecyloxyphenoxy)-PcH.sub.2123 2(3), 9(10), 16(17), 23(24)-Tetra(2-naphthyloxy)-PcH.sub.2124 2(3), 9(10), 16(17), 23(24)-Tetra(4-carboneopentyloxyphenylthio)-PcH.su b.2125 1,4,8,11,15,18,22,25-octahexyloxy-2,3,9,10,16,17,23,24-octachloro-PcSi( OH).sub.2126 1,4,8,11,15,18,22,25-octa-n-butoxy-2,3,9,10,16,17,23,24-octachloro-PcH. sub.2127 1,4,8,11,15,18,22,25-octa-isohexyloxy-2,3,9,10,16,17,23,24-octachloro-P cH.sub.2128 Hexadecamethyl-PcAlOH129 Hexadecaanilino-PcSi(OH).sub.2130 Hexadeca(4-methylphenylthio)-PcSi(OC.sub.6 F.sub.5).sub.2131 1,4,8,11,15,18,22,25-Octabutoxy-PcH.sub.2132 1, 4,8,11,15, 18,22, 25-Octaphenylthio-PcSi[ O--Si(CH.sub.3).sub.2 C.sub.6 H.sub.5 ].sub.2133 1,4,8,11,15,18,22,25-Octa-(4-n-hexyloxyphenoxy)-PcH.sub.2134 1,4,8,11,15,18,22,25-Octa-(4-t-butylphenylthio)-PcH.sub.2135 1,4,8,11,15,18,22,25-Octa-(4-octylthiophenylthio)PcSiCl.sub.2136 2,3,9,10,16,17,23,24-Octaethoxy-Pc--Al--OH137 2,3,9,10,16,17,23,24-Octa-(4-t-butylphenylthio)PcH.sub.2138 2,3,9,10,16,17,23,24-Octadecyloxy-Pc--SiCl.sub.2139 2,3,9,10,16,17,23,24-Octaphenylthio-PcSi(OC.sub.6 H.sub.5).sub.2140 2,3,9,10,16,17,23,24-Octa(12-acetoxydodecyloxy)PcSi[OC.sub.6 H.sub.4 -4-CO.sub.2 hexyl].sub.2141 2,3,9,10,16,17,23,24-Octa(2-ethylhexyl)PcSi(OCOCF.sub.3).sub.2142 2,3,9,10,16,17,23,24-Octa(2-isooctylphenylthio)-PcAlOH143 2,3,9,10,16,17,23,24-Octa(t-butoxyphenoxy)-PcAlCl144 2,3,9,10,16,17,23,24-Octa(6-isopropylbenzothiazol-2-ylthio)PcAlOH145 1,4,8,11,15,18,22,25-Octa(3-methylbutoxy)-2,3,9,10,16,17,23,24-octaphen ylthio-PcAlOH146 1,4,8,11,15,18,22,25-Octa(3-methylbutoxy)-2,3,9,10,16,17,23,24-octaphen oxy-PcSi(OH).sub.2147 1,4,8,11,15,18,22,25-Octa(3-methylbutoxy)-2,3,9,10,16,17,23,24-octa-n-b utylthio-PcAlOH148 1,4,8,11,15,18,22,25-Octa(3-methylbutoxy)-2,3,9,10,16,17,23,24-octa-4(t -butylphenylthio)PcAlCl149 1,4,8,11,15,18,22,25-Octafluoro-2,3,9,10,16,17,23,24-octaphenylthio-PcA lOC.sub.6 H.sub.4 -4-CO.sub.2 CH.sub.3150 1,4,8,11,15,18,22,25-Octafluoro-2,3,9,10,16,17,23,24-octaphenylthio-PcA lOH151 2(3), 9(10), 16(17), 23(24)-Tetra(N-cyclohexyl-N-decanylamino)-PcAlCl152 2(3), 9(10), 16(17), 23(24)-Tetra(3,5-di-t-butylphenoxy)PcH.sub.2153 2(3), 9(10), 16(17), 23(24)-Tetracyclohexanesulfonamido-PcAlOH154 2(3), 9(10), 16(17), 23(24)-Tetra[4-(carbo-2-ethylhexyloxy)phenoxy]PcH. sub.2155 2(3), 9(10), 16(17), 23 (24)-Tetra-[Si(CH.sub.3).sub.2 C.sub.6 H.sub.5 ]--PcAlCl156 2(3), 9(10), 16(17), 23(24)-Tetra[Si(OCH.sub.3).sub.3 ]--PcAlOH157 2(3), 9(10), 16(17), 23 (24)-Tetra[Sn(C.sub.4 H.sub. 9 -n).sub.3 --AlCl158 2(3), 9(10), 16(17), 23(24)-Tetra[Sn(Oamyl).sub.3 ]--PcAlOH159 2(3), 9(10), 16(17), 23(24)-Tetra[N-phenylbutanesulfonamido)-PcAlCl160 2(3), 9(10), 16(17), 23(24)-Tetra(N-octylbenzamido)-PcSi(OH).sub.2161 2(3), 8(11), 15(18), 22(25)-Tetraamino-PcAlOH162 PcAlOC.sub.6 H.sub.4 -4-CH.sub.2 CH.sub.2 OCOCH.sub.2 CH(C.sub.2 H.sub.5)C.sub.4 H.sub.9 -n163 PcAlOC.sub.6 H.sub.2 -3,5-di-CO.sub.2 octyl-4-NO.sub.2164 1,2,3,4,8,9,10,11,15,16,17,18,22,23,24,25-Hexadecyl(4-t-butylphenylthio )PcH.sub.2165 2(3), 9(10), 16(17), 23(24)-Tetra(3-pentadecylphenoxy)-PcH.sub.2166 2(3), 9(10), 16(17), 23(24)-Tetra(l,l-dimethylpropyl)-PcH.sub.2167 2(3), 9(10), 16(17), 23(24)-Tetra(l,l-dimethylpropyl)-PcAlOC.sub.6 H.sub.3 -3,5-di-CO.sub.2 cyclohexyl168 2(3), 9(10), 16(17), 23(24)-Tetra(n-dodecylthio)-PcAlOC.sub.6 H.sub.3 -3,5-di-CO.sub.2 -methyl169 1(4), 8(11), 15(18), 22(25)-Tetra-NHC.sub.8 H.sub.17 --PcH.sub.2170 1(4), 8(11), 15(18), 22(25)-Tetra-NHC.sub.12 H.sub.25 --PcH.sub.2171 1(4), 8(11), 15(18), 22(25)-Tetra-[N(COCF.sub.3)C.sub.8 H.sub.17 ]--PcAlCl172 1(4), 8(11), 15(18), 22(25)-Tetra-N(C.sub.8 H.sub.17).sub.2 --PcAlCl__________________________________________________________________________ TABLE 4__________________________________________________________________________NAPHTRALOCYANINE COMPOUNDS(Nc = NAPHTHALOCYANINE NUCLEUS)EX. NO.COMPOUND__________________________________________________________________________173 2(3), 11(12), 20(21), 29(30)-Tetra-t-butyl-NcH.sub.2174 2(3), 11(12), 20(21), 29(30)-Tetraisopentyl-NcAlOC.sub.6 H.sub.4-4-CO.sub.2 CH.sub.3175 2(3), 11(12), 20(21), 29(30)-Tetraisobutyl-NcSi(OH).sub.2176 2(3), 11(12), 20(21), 29(30)-Tetraisoamyl-NcAlOH177 2(3), 11(12), 20(21), 29(30)-Tetraoctyl-NcH.sub.2178 2(3), 11(12), 20(21), 29(30)-Tetraisohexyl-NcSi[OSn(C.sub.4 H.sub.9n).sub.3 ].sub.2179 2(3), 11(12), 20(21), 29(30)-Tetraoctyl-NcSi[OGe[Ohexyl].sub.3].sub.2180 2(3), 11(12), 20(21), 29(30)-Tetranonyl-NcSi(OCH.sub.2 CH.sub.2CH.sub.2 CH.sub.2 OC.sub.4 H.sub.9 n).sub.2181 2(3), 11(12), 20(21), 29(30)-Tetra-(2,2,4-trimethylpentyl)-NcAlOC.sub.6 H.sub.4 -4-CO.sub.2 methyl182 2(3), 11(12), 20(21), 29(30)-Tetra-(2-ethylhexyl)-NcAlOC.sub.6H.sub.3 -3,5-diCO.sub.2 dodecyl183 2(3), 11(12), 20(21), 29(30)-Tetra-t-butyl-NcSi(OC.sub.6 H.sub.4-4-CO.sub.2 cyclohexyl).sub.2184 2(3), 11(12), 20(21), 29(30)-Tetra-t-butyl-NcSi(OCO-t-butyl).sub.2185 2(3), 11(12), 20(21), 29(30)-TetrapentadecylNcH.sub.2186 2(3), 11(12), 20(21), 29(30)-Tetra(hexadecyloxy)-NcH.sub.2187 2(3), 11(12), 20(21), 29(30)-Tetra-t-butyl-NcZn188 2(3), 11(12), 20(21), 29(30)-Tetrabenzyl-NcAlOH189 2(3), 11(12), 20(21), 29(30)-Tetra(2-ethylhexyloxy)-NcAlCl190 NcSi(OCH.sub.2 CH.sub.2 CH.sub.2 CH.sub.2 OC.sub.4 H.sub.9 n).sub.2191 NcSiOCO(CH.sub.2).sub.7 CH.sub.3192 ##STR40##193 2(3), 11(12), 20(21), 29(30)-Tetra-[OC.sub.6 H.sub.4 CO.sub.2(CH.sub.2).sub.2 CH.sub.3 ]NcAlCl194 2(3), 11(12), 20(21), 29(30)-Tetra-[OC.sub.6 H.sub.3 -3,5-diCO.sub.2CH.sub.2 CH(CH.sub.3).sub.2 ]NcAlOH195 2(3), 11(12), 20(21), 29(30)-Tetra[SC.sub.6 H.sub.4 -3-CO.sub.2CH.sub.2 CH(CH.sub.3).sub.2 ]NcSi(OH).sub.2196 2(3), 11(12), 20(21), 29(30)-Tetra-n-butoxy-NcSi[OSi(C.sub.6H.sub.5).sub.3 ].sub.2197 2(3), 11(12), 20(21), 29(30)-Tetra-n-butoxy-NcSi[OCOC.sub.6 H.sub.11).sub.2198 2(3), 11(12), 20(21), 29(30)-Tetradodecyloxy-NcSi(OH).sub.2199 2(3), 11(12), 20(21), 29(30)-Tetra(6-dodecyloxybenzothiazol-2-ylthio)-NcAlOH200 2(3), 11(12), 20(21), 29(30)-Tetra(6-hexylbenzimidazol-2-ylthio)-NcAlOCOCF.sub.3201 2(3), 11(12), 20(21), 29(30)-Tetra(t-butylphenylseleno)-NcAlCl.sub.2202 2(3), 11(12), 20(21), 29(30)-Tetra(n-butylphenyltelluro)-NcSiCl.sub.2203 2(3), 11(12), 20(21), 29(30)-Tetra(t-butylanilino)-NcSi(OH).sub.2204 2(3), 11(12), 20(21), 29(30)-Tetra(6-n-butyl-2-naphthyloxy)-NcSi(OCOCF.sub.3).sub.2205 2(3), 11(12), 20(21), 29(30)-Tetra(6-neopentyl-2-naphthylthio)-NcSi(OCOCH.sub.3).sub.2206 2(3), 11(12), 20(21), 29(30)-Tetraallyloxy-NcAlOH207 2(3), 11(12), 20(21), 29(30)-Tetrapropargyloxy-NCSi(OH).sub.2208 2(3), 11(12), 20(21), 29(30)-Tetra(cyclohexyloxy)-NCSi[OC.sub.6H.sub.3 -3,5-diCO.sub.2 CH.sub.3 ].sub.2209 2(3), 11(12), 20(21), 29(30)-Tetra(2-phenoxyethoxy)-NcAlOH210 2(3), 11(12), 20(21), 29(30)-Tetra(2-phenylethoxy)-NcH.sub.2211 2(3), 11(12), 20(21), 29(30)-Tetra(benzyloxy)-Nc AlOH212 2(3), 11(12), 20(21), 29(30)-Tetrapiperidino-NcSi(OH).sub.2213 5,9,14,18,23,27,32,36-Octa(N-n-butyl-N-phenylamino)-NcSi(OH).sub.2214 5,9,14,18,23,27,32,36-Octa(di-N,N-n-butylamino)-NcAlCl215 5,9,14,18,23,27,32,36-Octa-n-butoxy-NcSi(OCCOCF.sub.3).sub.2216 5,9,14,18,23,27,32,36-Octa-n-butoxy-NcSi(OH).sub.2217 5,9,14,18,23,27,32,36-Octaphenoxy-NcH.sub.2218 5,9,14,18,23,27,32,36-Octaallyloxy-NcAlOC.sub.6 H.sub.4 -4-CO.sub.2menthyl219 5,9,14,18,23,27,32,36-Octa(octylthio)-NcAlCl220 2(3), 11(12), 20(21), 29(30)-Tetra(4-t-butylphenoxy)-NcAlOH221 2(3), 11(12), 20(21), 29(30)-Tetra(4-isoamylphenoxy)-NcAlCl222 2,3,11,12,20,21,29,30-Octa(4-cyclohexylphenoxy)-NcSi(OH).sub.2223 2,3,11,12,20,21,29,30-Octa(hexadecyloxy)-NcAlOH224 2,3,11,12,20,21,29,30-Octa(octadecyloxy)-NcSi(OH).sub.2225 2,3,11,12,20,21,29,30-Octa(icosanyloxy)-NcSi(OCOCF.sub.3).sub.2226 2,3,11,12,20,21,29,30-Octa(2-ethylhexyloxy)-NcAlCl227 2,3,11,12,20,21,29,30-Octa(undecanyloxy)-NcAlOH228 2,3,11,12,20,21,29,30-Octa(4-t-butoxyphenoxy)NcAlOH229 2,3,11,12,20,21,29,30-Octa(4-n-butoxyphenylthio)NcSi(OH).sub.2230 2,3,11,12,20,21,29,30-Octa(2-ethylhexoxy)-NcSi(OH).sub.2231 2,3,11,12,20,21,29,30-Octa[CH.sub.3 O(CH.sub.2 CH.sub.2 O).sub.3]NcAlCl232 2,3,11,12,20,21,29,30-Octa[OCH.sub.2 CH.sub.2 OCOCH.sub.2 CH(C.sub.2H.sub.5)C.sub.4 H.sub.9 n]NcSi(OH).sub.2233 2,3,11,12,20,21,29,30-Octa(4-t-butoxybutylthio)-NcAlOH234 2,3,11,12,20,21,29,30-Octamethyl-NcAlOH235 2,3,11,12,20,21,29,30-Octa-(4-t-butylphenylthio)-NcSi(OH).sub.2236 2(3), 11(12), 20(21), 29(30)-Tetradiethylamino-NcAlOH237 2(3), 11(12), 20(21), 29(30)-Tetramorpholino-NcAlOCOCF.sub.3238 2(3), 11(12), 20(21), 29(30)-Tetra-O(C.sub.2 H.sub.4 O).sub.2CH.sub.3 NcSiCl.sub.2239 2(3), 11(12), 20(21), 29(30)-Tetra-O(C.sub.2 H.sub.4 O).sub.3CH.sub.3 NcSi(OH).sub.2240 2(3), 11(12), 20(21), 29(30)-Tetra[(CH.sub.3).sub.3 SiCH.sub.2S]NcSi[OSi(C.sub.4 H.sub.9).sub.3 ].sub.2241 2(3), 11(12), 20(21), 29(30)-Tetra[(C.sub.2 H.sub.5).sub.3 Si(CH.sub.2).sub.2 S]NcSi[OSi(CH.sub.3).sub.3 ].sub.2242 2(3), 11(12), 20(21), 29(30)-Tetra[(C.sub.6 H.sub.11).sub.3 SiCH.sub.2 S]NcSi[OSi(OCH.sub.3).sub.3 ].sub.2243 2(3), 11(12), 20(21), 29(30)-Tetra[(CH.sub.3 O).sub.3 Si(CH.sub.2).sub.3 S]NcGe[OSi(C.sub.2 H.sub.5).sub.3 ].sub.2244 2(3), 11(12), 20(21), 29(30)-Tetra[(C.sub.6 H.sub.5 O).sub.3SiCH.sub.2 S]NcGe[OSi(OCH.sub.3).sub.3 ].sub.2245 2(3), 11(12), 20(21), 29(30)-Tetra[(CH.sub.3).sub.3 SiCH.sub.2CH.sub.2 O]NcSi(OH).sub.2 ]246 2(3), 11(12), 20(21), 29(30)-Tetra[(CH.sub.3).sub.3 SiC(Cl).sub.2CH.sub.2 S]NcSi[OSi(CH.sub.3).sub.3 ].sub.2247 2(3), 11(12), 20(21), 29(30)-Tetra[(C.sub.6 H.sub.5).sub.3 SiCH.sub.2 O]NcAlOH248 2(3), 11(12), 20(21), 29(30)-Tetra[(CH.sub.3).sub.3 SiCH.sub.2S]NcSi[OSi(C.sub.2 H.sub.5).sub.3 ].sub.2249 2(3), 11(12), 20(21), 29(30)-Tetra[(CH.sub.3).sub.3 SiCH.sub.2S]NcSi[OC.sub.18 H.sub.37).sub.2250 2(3), 11(12), 20(21), 29(30)-Tetra[(CH.sub.3).sub.2 C.sub.6 H.sub.5Si(CH.sub.2).sub.4 O]NcAlOH251 2,3,11,12,20,21,29,30-Octa[(CH.sub.3).sub.3 SiCH.sub.2 S]NcSi(OH).sub.2252 5(36), 9(14), 18(23), 27(32)-Tetra(4-t-butylphenyl)-2(3),11(12),20(21),29(30)-tetra-t-butyl-NcH.sub.2253 5(36), 9(14), 18(23), 27(32)-Tetra(4-hexylphenyl)-NcH.sub.2254 5(36), 9(14), 18(23), 27(32)-Tetra(4-octylphenyl)-NcH.sub.2255 5(36), 9(14), 18(23), 27(32)-Tetra(4-dodecylohexyl)-NcAlOH256 1(4), 10(13), 19(22), 28(31)-Tetra(dodecylamino)-NcAlCl257 1(4), 10(13), 19(22), 28(31)-Tetra(n-octylamino)-NcAlOH258 1(4), 10(13), 19(22), 28(31)-Tetra(n-octylamino)-NcAlOC.sub.6H.sub.3 -3,5-di-CO.sub.2 CH.sub.3259 2(3), 11(12), 20(21), 29(30)-Tetra(dodecylthio)-NcAlOH260 2(3), 11(12), 20(21), 29(30)-Tetra(n-octylthio)-NcAlCl261 2(3), 11(12), 20(21), 29(30)-Tetra(dodecylthio)-NcAlOC.sub.6 H.sub.3-3,5-di-CO.sub.2 CH.sub.3262 2,3,11,12,20,21,29,30-Octa(dodecylthio)NcSi(OH).sub.2263 2,3,11,12,20,21,29,30-Octa(dodecylthio)NcSi(OC.sub.6 H.sub.4-4-CO.sub.2 CH.sub.3).sub.2264 NcSi(OCOC.sub.6 H.sub.4 -4-t-butyl).sub.2265 NcSi[OCOC.sub.6 H.sub.4 -4-CO.sub.2 (CH.sub.2).sub.12 CH.sub.3].sub.2266 NcSi[COCONHC.sub.6 H.sub.4 -4-CO.sub.2 (CH.sub.2 CH.sub.2 O).sub.3CH.sub.3 ].sub.2267 NcSi[OCONHC.sub.6 H.sub.3 -3,5-di-CO.sub.2 CH.sub.2 CH(C.sub.2H.sub.5)C.sub.4 H.sub.9 -n].sub.2268 2(3), 11(12), 20(21), 29(30)-Tetra-t-butyl-NcMg269 NcSi[OC.sub.6 H.sub.3 -3,5-diCO.sub.2 CH.sub.2 CH(C.sub.2 H.sub.5)C.sub.4 H.sub.9 -n].sub.2270 NcAlOC.sub.6 H.sub.4 -4-OC.sub.10 H.sub.21271 2(3), 11(12), 20(21), 29(30)-Tetra(2-ethylhexylamino)NcH.sub.2272 2(3), 11(12), 20(21), 29(30)-Tetra(4-t-butylphenoxy)NcZn273 2(3), 11(12), 20(21), 29(30)-Tetra(4-n-hexylphenylthio)NcMg274 2(3), 11(12), 20(21), 29(30)-Tetra[4-CHNCH.sub.2 (C.sub.2 H.sub.5)C.sub.4 H.sub.9 n-phenoxy]NcH.sub.2275 NcSi[OC.sub.6 H.sub.4 -4-CHNC.sub.6 H.sub.4 -4-CO.sub.2 CH.sub.2CH(C.sub.2 H.sub.5)C.sub.4 H.sub.9 -n].sub.2__________________________________________________________________________ TABLE 5__________________________________________________________________________CROCONIC ACID DERIVED COMPOUNDS ##STR41##EX. NO.R.sub.1, R.sub.2 R.sub.3, R.sub.4 R', R"__________________________________________________________________________276 7-CO.sub.2 (CH.sub.2).sub.3 CH.sub.3 H CH.sub.3277 7-CO.sub.2 CH.sub.2 CH(C.sub.2 H.sub.5)(CH.sub.2).sub.3 CH.sub.3 H CH.sub.3278 7-CO.sub.2 NHC.sub.8 H.sub.17 H CH.sub.3279 7-CO.sub.2 NHC.sub.6 H.sub.4 -4-C(CH.sub.3).sub.3 CH.sub.3 CH.sub.3280 7-SO.sub.2 NHC.sub.12 H.sub.25 C.sub.6 H.sub.5 CH.sub.3281 7-(CH.sub.2).sub.7 CH.sub.3 CH.sub.2 CH.sub.3 CH.sub.3282 7-CO.sub.2 C.sub.6 H.sub.10 -4-CH.sub.3 CH.sub.3 CH.sub.3, CH.sub.2 CH.sub.3283 7-SO.sub.2 (CH.sub.2).sub.3 CH(CH.sub.3)CH.sub.3 H CH.sub.3, CH(CH.sub.3).sub.2284 7-CO.sub.2 C.sub.6 H.sub.4 -4-O(CH.sub.2).sub.12 CH.sub.3 H CH.sub.3, CH.sub.2 CH(CH.sub.3).sub.2285 7-CO.sub.2 NHC.sub.6 H.sub.4 -4-C.sub.6 H.sub.11 H CH.sub.3286 7-SO.sub.2 NHCH.sub.2 (CH.sub.2 CH.sub.3)C.sub.6 H.sub.9 n H CH.sub.3287 7-SO.sub.2 N(C.sub.4 H.sub.9 n)C.sub.6 H.sub.11 H CH.sub.3288 7-S(CH.sub.2).sub.10 CH.sub.3 H CH.sub.3289 7-OCH.sub.2 CH(C.sub.2 H.sub.5)C.sub.4 H.sub.9 n H CH.sub.3290 8-(CH.sub.2).sub.3 CH.sub.3 H CH.sub.3__________________________________________________________________________

This invention provides a method for imparting invisible markings for identification purposes to petroleum hydrocarbons by incorporating one or more infrared fluorescing compounds therein. Certain infrared fluorophores from the classes of squaraines (derived from squaric acid), phthalocyanines and naphthalocyanines are useful in providing invisibly marked petroleum hydrocarbons such as crude oil, lubricating oils, waxes, gas oil (furnace oil), diesel oil, kerosene and in particular gasoline. The near infrared fluorophores are added to the hydrocarbons at extremely low levels and are detected by exposing the marked hydrocarbon compositions to near infrared radiation having a wavelength in the 670-850 nm range and then detecting the emitted fluorescent light via near infrared light detection means.

CROSS-REFERENCE TO RELATED APPLICATIONS [0001] This application claims priority from U.S. Provisional Patent Application No. 60/437,606 filed Jan. 2, 2003. BACKGROUND OF THE INVENTION [0002] The present invention relates generally to roof construction and repair, and in particular the present invention relates to an undersiding flashing receiver. [0003] The problem of how to seal and make waterproof or water resistant vertical and horizontal building surfaces is as old as the building trades. In its most rudimentary fashions, this problem was solved by the blending and sealing of the vertical and horizontal surfaces with sheet metal such as sheet copper, aluminum or lead. This sheet metal is often referred to as flashing. The sealing of the flashing to the respective surfaces was effected with a mastic such as tar. This method of sealing building surfaces is still commonly used. [0004] In the past few decades, a new form of building renewal has come into wide spread use namely the trade of applying interlocking siding to the vertical surfaces of buildings in order to give these surfaces a new appearance. In this regard, the application of interlocking panels of vinyl and aluminum siding to older structures has become quite common. Because this siding is often applied to older structures, two problems often arise. [0005] First, the roofing on the structure is often replaced at intervals of fifteen to twenty-five years. Additionally, damage as a result of high wind, hail, carpenter ants, termites, fire, improper ventilation, sun, shingle manufacturing defects, falling trees, ice dams, etc. may necessitate the repair or replacement of the roof. With a structure's life expectancy of one hundred years, multiple applications of roofing are possible. When repairing or replacing the roof, it is usually necessary to replace all flashing. Current methods and devices do not provide a roof-siding transition such that the flashing may easily be replaced. [0006] The second problem arises when siding installers place a nail through the lower end of the new siding and the roof-wall transition flashing. This greatly complicates the repair or replacement of the flashing or roofing material because the siding must be removed to replace the flashing. The replacement of the flashing is further complicated by multiple layers of siding, as in the case of new siding installed directly over existing exterior wall coverings. Two layers of siding nailed to the flashing and the wall prevents repair or replacement of the flashing or roofing material in accordance with current Asphalt Roofing Manufacturers' Association Standards or the Standards of the National Association of Roofing Contractors. [0007] Moreover, it has recently been recognized that the bottom of sidings adjacent to roof areas should be maintained at a minimum distance above the roof covering to prevent moisture from seeping into and rotting the lower wall boards. Today, many siding installers, out of carelessness or ignorance, set a siding “J” channel directly on the roofing material or at an inadequate height above the roof. Placing the “J” channel directly on the roof does not provide the minimum distance required by most siding manufacturers nor does it allow for future repair or replacement of the flashing. This is an adverse situation for the customer because now the top layer of siding has to be removed so that new flashing can be installed. This adds considerable costs to the job of roof repair or replacement. [0008] The present invention is directed to overcoming one or more of the problems set forth above. BRIEF SUMMARY OF THE INVENTION [0009] It is a principal aspect of the present invention to supply and maintain a void for receiving flashing material at a desired location to correctly locate wall coverings, such as siding. The application of this void will allow the immediate and future repair or replacement of the flashing or roofing material without removal of the wall covering. It will ultimately provide a benefit to the customer by reducing the costs to repair or replace roofing materials over the life of the building. [0010] It is another aspect of the present invention to provide for quick installation of new flashing due to a back flange of the flashing being set directly on the roof sheathing. This automatically sets a front flange at the correct position for properly locating the siding. A bottom of the front flange is set so that the wall covering end runs parallel with it. Depending on the type of wall covering used or its location, use of a plain receiver, “J” channel receiver, or a starter strip receiver may be necessary. [0011] Yet another aspect of the present invention is to provide an upper area of the void with a locating feature that stops the front flange from being nailed back tight; thus ensuring that the undersiding flashing receiver remains open to receive flashing. [0012] Another aspect of the present invention is to provide an undersiding flashing receiver made from standard siding materials and color matched to the most common shades of contemporary siding colors. [0013] The above aspects are accomplished by an undersiding flashing receiver comprising a thin gauge material that is shaped to properly locate siding and receive the flashing. [0014] The above aspects are merely illustrative and should not be construed as all-inclusive; nor should they be construed as limiting the scope of the invention. BRIEF DESCRIPTION OF THE DRAWINGS [0015] Reference is now made to the accompanying drawings which illustrate the best known mode for carrying out the invention: [0016] [0016]FIG. 1 is a side view of a first embodiment of an undersiding flashing receiver; [0017] [0017]FIG. 2 is a front view of the embodiment shown in FIG. 1; [0018] [0018]FIG. 3 is a perspective view of the first embodiment illustrating its use in a roof-wall transition; [0019] [0019]FIG. 4 is a cross-sectional view generally taken along line 3 - 3 in FIG. 3; [0020] [0020]FIG. 5 is a side view illustrating a second embodiment of the undersiding flashing receiver; [0021] [0021]FIG. 6 is a front view of the embodiment shown in FIG. 5; [0022] [0022]FIG. 7 is a side view illustrating a third embodiment of the undersiding flashing receiver; [0023] [0023]FIG. 8 is a front view of the embodiment shown in FIG. 7; [0024] [0024]FIG. 9 is a side view illustrating a fourth embodiment of the undersiding flashing receiver; [0025] [0025]FIG. 10 is a front view of the embodiment shown in FIG. 9; [0026] [0026]FIG. 11 is a side view illustrating a fifth embodiment of the undersiding flashing receiver; [0027] [0027]FIG. 12 is a front view of the embodiment shown in FIG. 11; [0028] [0028]FIG. 13 is a side view illustrating a sixth embodiment of the undersiding flashing receiver; and [0029] [0029]FIG. 14 is a front view of the embodiment shown in FIG. 13. DETAILED DESCRIPTION OF THE INVENTION [0030] Referring now to the drawings, and initially to FIGS. 1 and 2, an undersiding flashing receiver is generally indicated by numeral 10 . The undersiding flashing receiver 10 includes a thin gauge material 12 which may be bent or extruded into the desired shape. The thin gauge material 12 is preferably extruded vinyl but can also be made from aluminum, galvanized steel, or copper. If the undersiding flashing receiver 10 is to be made from metal, sheets or coilstock may be used. [0031] The undersiding flashing receiver 10 also includes a first leg 11 , a second leg 17 , and an intermediate member 14 . The intermediate member 14 is also referred to as a spacer. The spacer 14 is made from resilient material, such as foam or rubber, and provides a gap 16 for receiving standard flashing. The depicted embodiment of the undersiding flashing receiver 10 further includes a “J” channel 18 . The “J” channel 18 forms a gutter 13 for receiving exterior wall coverings, such as siding. The “J” channel 18 is at a height H above a bottom 15 of the undersiding flashing receiver 10 such that a standard flashing may be easily inserted or removed after the undersiding flashing receiver 10 is installed. The “J” channel 18 must also overlap the top portion of the standard flashing to prevent water from seeping behind the standard flashing. The overlap should be no less than one-half inch (13 millimeters). The use of the “J” channel 18 properly locates a wall covering, such as siding, at a vertical distance above the flashing and/or roof. [0032] Referring now to FIGS. 3 and 4, there is shown one possible use of the first embodiment. In this application, the undersiding flashing receiver 10 is provided as part of the roof-wall transition and mounted to a wall 38 . The undersiding flashing receiver 10 may be mounted using various fastening devices, such as nails or screws. A standard flashing 32 is inserted into the undersiding flashing receiver 10 and is secured to a roof 33 . Roofing material 24 covers the roof 33 and a portion of the standard flashing 32 . The undersiding flashing receiver 10 also receives a lower portion of siding 26 . The undersiding flashing receiver 10 properly spaces the siding 26 above the roof 33 . The siding 26 covers the wall 38 . In this manner, the siding 26 is properly spaced above the roof and the flashing may be easily removed at some later date in the event of roof repair or replacement. [0033] In FIGS. 5 and 6, a second embodiment of the undersiding flashing receiver is generally indicated by numeral 40 . The undersiding flashing receiver 40 includes a thin gauge material 42 , a first leg 43 , a second leg 45 , and an intermediate member 44 . The undersiding flashing receiver 40 also includes slots 46 . The slots 46 may be used to operatively connect a starter strip, commonly known in the art and therefore not described in more detail, to the undersiding flashing receiver 40 . The slots 46 may also be nail slots for securing the undersiding flashing receiver 40 . The combination of the undersiding flashing receiver 40 and the starter strip may be used for applications where the siding and the roof are not perpendicular to one another but are at an obtuse angle. An example of this situation may be the transition between a porch roof and vertical siding. The slots 46 may be omitted in some instances, such as when a starter strip is not necessary for the application. [0034] [0034]FIGS. 7 and 8 illustrate a third embodiment of the. undersiding flashing receiver, generally indicated by numeral 50 . The undersiding flashing receiver includes a first leg 53 and a second leg 55 . In the depicted embodiment, the undersiding flashing receiver 50 includes a starter strip 56 for the installation of siding. The use of this embodiment eliminates the need for additional components when transitioning from the roof to the siding in an application where the roof and the siding are substantially in the same plane or at an obtuse angle to each other. The undersiding flashing receiver 50 also includes a thin gauge material 52 and an intermediate member 54 . [0035] A fourth embodiment of the undersiding flashing receiver, generally indicated by numeral 60 , is shown in FIGS. 9 and 10. The undersiding flashing receiver 60 may include nail slots 66 for the purpose of installation. The undersiding flashing receiver 60 is similar to the first embodiment in that it includes a “J” channel 68 forming a gutter 63 for receiving exterior wall coverings, such as siding. The undersiding flashing receiver 60 includes a first leg 62 , a second leg 67 , and an intermediate member 61 . [0036] As seen in FIG. 9, the undersiding flashing receiver 60 has an upper surface 64 and a lower surface 65 . The upper surface 64 is used to attach the undersiding flashing receiver 60 to a substantially vertical member, such as a wall. The lower surface 65 is shown offset from the upper surface 64 for the purpose of allowing a flashing to be located between the lower surface 65 and the substantially vertical member. While a parallel offset is shown, other transitions between upper surface 64 and lower surface 65 may be used. What is important is that lower surface 65 is located at a sufficient distance away from the mounting surface (i.e. upper surface) 64 such that a flashing can be inserted between the lower surface 65 and a substantially vertical member, such as a wall. [0037] FIGS. 11 - 14 illustrate two additional embodiments. In FIGS. 11 and 12, an undersiding flashing receiver 70 includes an extended tip 72 . Alternatively, a wall covering, such as siding, may be directly attached to the extended tip 72 . In some embodiments the undersiding flashing receiver 70 includes a starter strip, similar to the starter strip 56 shown in Fib. 7 , attached to the extended tip 72 . The undersiding flashing receiver 70 may include nail slots 76 for installation. The undersiding flashing receiver 70 also includes a first leg 71 , a second leg 73 , and an intermediate member 75 . [0038] An undersiding flashing receiver 80 shown in FIGS. 13 and 14 is similar to the embodiment shown in FIG. 9 except that it does not include a “J” channel. The undersiding flashing receiver 80 has an upper surface 84 and a lower surface 85 . The lower surface 85 is shown offset from the upper surface 84 for the purpose of allowing a flashing to be located between the lower surface 85 and the substantially vertical member, such as a wall. While a parallel offset is shown, other transitions between upper surface 84 and lower surface 85 may be used. What is important is that lower surface 85 is located at a sufficient distance away from the mounting surface (i.e. upper surface) 84 such that a flashing can be inserted between the lower surface 85 and a substantially vertical member, such as a wall. The undersiding flashing receiver 80 may include nail slots 86 for installation. The undersiding flashing receiver 80 also includes a first leg 82 , a second leg 83 , and an intermediate member 87 . [0039] A method of using an undersiding flashing receiver includes locating the undersiding flashing receiver along lower boards of a wall adjacent to a roof, securing the undersiding flashing receiver to the wall, inserting a flashing into the undersiding flashing receiver, securing the flashing to the roof, at least partially covering the roof and flashing with roofing material, and operatively connecting exterior wall coverings to the undersiding flashing receiver. [0040] Other aspects, objects and advantages of the present invention can be obtained from a study of the drawings, the disclosure and the accompanying claim. The invention in its broader aspects is not limited to the specific steps and apparatus shown and described but departures may be made therefrom within the scope of the accompanying claim without departing from the principles of the invention and without sacrificing its chief advantages. For example, while the above illustrates the use of an undersiding flashing receiver in home construction, it can equally be adapted for commercial building construction.

An undersiding flashing receiver for use on a roof-wall transition to weatherproof a new or existing home. The undersiding flashing receiver is comprised of thin gauge material shaped to properly locate an exterior wall covering, such as siding, and receive flashing. The undersiding flashing receiver also includes a spacer to provide a gap to receive the flashing.

FIELD OF THE INVENTION The present invention is directed to a method for isolating and identifying the nucleotide sequence for a novel macrophage receptor with a collagenous domain, termed "MARCO". In addition, the invention relates to the nucleotide sequence for MARCO identified by the process of the invention and the isolated and purified polypeptide chain encoded by such a nucleotide sequence. The invention also provides for the use of the identified nucleotide sequence (or fragments thereof) to detect the gene or its parts, or its mRNA transcript in tissue, cell or fluid samples in normal or pathological situations. Moreover, the invention relates to the production of MARCO as recombinant protein or purified from tissues as well as for the generation of antibodies against the protein itself, and for the use of such antibodies to detect the protein in tissue, cell or fluid samples, or to interfere with the function of the receptor. BACKGROUND OF THE INVENTION Macrophages are bone marrow-derived cells that form an important part of the host defense system. They play a role in physiological as well as pathological processes, such as inflammation, fibrosis atherogenesis, and tumor invasion. Macrophages are relatively large (10-20 μm), long-lived, amoeboid, phagocytic and pinocytotic cells present in blood, lymph and other tissues. They are derived from monocytes which form a pool of precursors migrating from blood into peripheral tissues such as liver, spleen, lung, lymph nodes, peritoneum, skin, brain and bone, where they differentiate into macrophages with organ specific features. Macrophages play important roles in host resistance to a variety of pathogenic microorganisms, having important functions in, for example, phagocytosis, inflammation, antibody formation, cell-mediated cytotoxicity and delayed hypersensitivity. In this regard, the major characteristic of macrophages is their ability to recognize, internalize and destroy a variety of foreign and endogenous substances and, thus, to function as scavengers that engulf pathogenic organisms, such as bacteria, parasites and viruses. Macrophages also remove extravasated blood cells or dead cells in tissues and, thereby, participate in the maintenance of tissues. Furthermore, macrophages are thought to play a role in immune response by presenting foreign antigens (i.e., are antigen-presenting cells) to lymphocytes. The macrophages have been shown to be able to bind "nonself" pathogens directly, or they recognize pathogens as foreign because they have been coated by antibodies or complement. The exact recognition mechanism is unknown, but it has been proposed that receptors with broad binding specificity are used to discriminate between self and nonself. Scavenger receptors are macrophage cell membrane proteins that can bind a variety of substances and facilitate their uptake and removal from blood or connective tissue (see Krieger and Hertz, Ann. Rev. Biochem. 63, 601-637, 1994). The macrophage scavenger receptors have been suggested to play a role in the binding of foreign antigens, in addition to their apparently important role in atherogenesis. These receptors have unusually broad ligand binding specificity and, thus, differ from many other cell surface receptors. Scavenger receptors of types I and II are trimeric membrane proteins with a small N-terminal intracellular domain, a transmembrane domain, and an extracellular portion containing a short spacer domain, an α-helical coiled coil domain, and a short triple-helical collagenous domain (Krieger and Hertz, Ann. Rev. Biochem., 63,601-637, 1994). The type I scavenger receptor differs from the type II scavenger receptor in that it contains an additional C-terminal cysteine-rich domain. These receptors, which are present in macrophages in diverse tissues, such as liver and lung, have been shown to bind a variety of ligands such as chemically modified lipoproteins and albumin, polyribonucleotides, polysaccharides, phospholipids, asbestos etc. It has been proposed that the scavenger receptors play a key role in the development of atherosclerosis where they mediate macrophage uptake of modified low density lipoproteins (LDL) in arterial walls. Furthermore, the scavenger receptors are likely to function in host defense as some forms of gram-negative bacterial endotoxin and gram-positive bacteria can serve as their ligands. The collagenous domain of the scavenger receptor has been shown to mediate the binding activities assigned to these receptors. The collagenous domain of the scavenger receptor is a triple helix formed by three chains which contain 24 consecutive Gly-Xaa-Yaa-triplets. Such Gly-Xaa-Yaa-triplets are the hallmark of the α chains of collagens, which are a family of extracellular proteins constituting the major structural proteins of the extracellular matrix. There are several proteins without structural functions that contain collagenous domains. As the scavenger receptors, most of those belong to the host defense mechanisms, such as complement factor C1q, conglutinin, mannose binding proteins, and pulmonary surfactant associated proteins. All these proteins are thought to participate in the removal of extracellular debris such as pathogenic material. Furthermore, enzymes such as acetyl cholinesterase and bacterial pullulanase contain collagenous domains. Along these lines, applicants have identified and characterized a novel and unique macrophage receptor with collagenous structure. This protein, which shows structural homology with scavenger receptor type I, was expressed strongly after birth in a subset of macrophages in mouse spleen and lymph nodes. Furthermore, it is expressed in peritoneal macrophages, but not by macrophages of the liver or lung. The receptor was shown to bind bacteria and acetylated LDL, but not yeast. Based on its binding activity and distribution, the biological role of this receptor is believed to be related with immune defense and/or phagocytosis. The results suggest that the novel protein discovered by applicants is a macrophage-specific membrane receptor which has a role in host defense as it is expressed after birth in subpopulation of macrophages that are considered responsible for the binding of bacterial antigens and phagocytosis. SUMMARY OF THE INVENTION The present invention is directed to processes for isolating and identifying the nucleotide sequence of a gene for a novel macrophage receptor with collagenous structure, termed "MARCO" by the applicants. The new macrophage receptor with a collagenous domain binds gram positive and negative bacteria and acetylated LDL. Moreover, the invention relates to the nucleotide sequence for MARCO identified by the process of the invention and the isolated and purified polypeptide chain encoded by such a nucleotide sequence. Further, the invention provides for the use of the identified nucleotide sequence, or DNA fragments thereof, to prepare DNA or RNA probes, radiolabeled, enzyme-labeled, chemiluminescence-labeled, avidin or biotin-labeled, or containing modified nucleotides, incorporated into a self-replicating vector, a viral vector, linear or circular, to detect the presence of the gene or mutations in the gene which can directly or indirectly produce disease. The invention also relates to the use of gene fragments from human genomic or cloned DNA for detection and analysis of the gene. Additionally, the invention provides for the use of identified DNA sequence to correct for gene defects leading to mutations causing a malfunctioning MARCO. The instant invention also provides for methods for detecting the presence of specific MARCO mRNA in cells and tissues with an effective amount of nucleic acid probe, which probe contains a sense or antisense of MARCO mRNA sequence. In particular, the probes containing the identified nucleotide sequence or fragments thereof, radiolabeled, enzyme-labeled, chemiluminescence-labeled, avidin or biotin-labeled, or containing modified nucleotides, incorporated into a self-replicating vector, a viral vector which can be linear or circular. The instant invention also provides for methods for generating the MARCO protein as recombinant protein or fragments thereof by inserting the gene into micro-organisms and expressing it in micro-organisms or eukaryotic cells. Similarly, the invention provides for the synthesis of peptides from the MARCO polypeptide chain based on the amino acid sequence derived from the coding sequence of the cloned gene. The present invention also provides for the generation of immunoreactive antibodies, made against the MARCO protein or parts thereof, including synthetic peptides, that specifically detect the receptor protein and which can be used to detect the expression of the receptor in tissue, cell and fluid samples as well as for interfering with the binding of ligands such as bacteria to the macrophage receptor. Furthermore, the present invention involves several different embodiments. The invention provides clones coding for the entire mouse MARCO polypeptide chain. The invention is directed, in particular, to a full-length mouse cDNA clone Maf-6. In addition, the invention provides for nucleotide sequences which encode the entire mouse amino acid sequences of the MARCO polypeptide. Furthermore, the invention provides for vectors containing parts of the mouse Maf-6 cDNA for the production of recombinant proteins. The invention also provides for two types of polyclonal antibodies recognizing the intra and extracellular domains of murine MARCO, respectively. These and other objects and features of the invention will be apparent from the following drawings, detailed description of the invention and from the claims. It should, however, be understood that the detailed description and the specific examples, while indicating preferred embodiments of the invention, are given by way of illustration only, since various modifications and changes within the spirit and scope of the invention will become apparent to those skilled in the art. BRIEF DESCRIPTION OF THE DRAWINGS The following is a brief description of the drawings which are presented for the purpose of illustrating the invention and not for the purpose of limiting same. FIG. 1 shows restriction map of a cDNA clone (Maf-6) coding for the mouse MARCO subunit polypeptide chain. The 5'- and 3'-end orientations are indicated. Restriction endonuclease cleavage sites EcoRI (E) and Pst I (P) are shown. The translation initation site (ATG) and termination (TGA) sites and a potential polyadenylation site (AATAAA) are shown as well as a poly (A) tail (AAAAAA). Scale in base pairs is shown below the clone. FIGS. 2A and B show the nucleotide sequence (first line) of the murine MARCO chain cDNA (SEQ ID NO: 1) and its predicted (deduced) amino acid sequence (second line) shown with the one letter code (SEQ ID NO: 2). The tentative transmembrane domain II is indicated by an underline and cysteine residues and the two potential glycosylation sites are circled. The 3' end termination codon is indicated by "ter". A putative polyadenylation signal AATAAA is double-underlined. FIG. 3 depicts the predicted tertiary structure of the macrophage MARCO receptor. The MARCO receptor is a trimeric protein containing an N-terminal end intracellular domain I, a transmembrane domain II, and an extracellular domain consisting of a "spacer" domain III, a collagenous domain IV with 89 Gly-Xaa-Yaa-repeat sequences interrupted at one location and a C-terminal end cysteine-rich domain V. FIGS. 4A-4H show the results of in situ hybridization analyses of MARCO expression and comparison of immunolocalization of MARCO and macrophage R-TR9 and MOMA-1 antigens in mouse spleen and lymph node. Hybridization with the MARCO antisense probe (A,B) showed strong signals in cells located in a circle-like array in the marginal zone (mz) between the white (w) and red (r) pulps. Immunostaining with an antibody against the intracellular domain I of MARCO (C) and with the ER-TR9 antibody specific for marginal zone macrophages (D) showed codistribution of antigens. Double-staining with MARCO (blue) and MOMA-1 (red) antibodies showed some marginal zone macrophages positive for MARCO, but negative for ER-TR9 (E). Double-staining with MARCO (blue) and MOMA-1 (red) antibodies shows respectively, staining of marginal zone macrophages and metallophilic macrophages lining the marginal sinus (F). Hybridization with the MARCO antisense probe (G and H, dark and light fields, respectively) showed strong signals in cells located in the meduallary cord region of lymph node. E, capsule; mc, medullary cord; pc, paracortex. Bars in A, 800 μm; in C, D, E and F, 35 μm; in G and H, 400 μm. FIGS. 5A-5B shows localization of the MARCO protein on the surface of cultured IC-21 macrophages using field emission scanning immunoelectron microscopy carried out with a polyclonal antibody against the extracellular domain. In FIG. 5A, intense gold label can be seen on the cell surface proper and pseudopodia (×10,000). FIG. 5B is magnification (×50,000) of pseudopodia. No label was observed with antibodies against domain I (not shown). FIG. 6 demonstrates binding of MARCO antibodies to spleen marginal zone macrophages in vivo. Rabbit antiserum to the extracellular domain V of MARCO was injected intravenously into mouse after which tissue was removed and processed for staining using a FITC-labeled anti-rabbit IgG. The label was confined to marginal zone (mz) macrophages located between the red (r) and white (w) pulps. Antibodies against domain I did not bind cells (not shown). FIGS. 7A-7B show immunoprecipitation and immunoblot analyses of MARCO protein from mouse tissues and transfected COS cells. In FIG. 7A, protein from spleen and kidney was extracted, immunoprecipitated with antisera against recombinant domains I (N) or V (C) of MARCO, electrophoresed on a 5% gel without reduction and immunoblotted. The antisera precipitated a 210,000 dalton protein from spleen (lanes 1 and 2), while no proteins were precipitated from the kidney (lanes 3 and 4) extract. The broad band of about 160,000 daltons seen in both spleen and kidney samples is immunoglobulin. When the same samples were electrophoresed on 8% gels after reduction, a major band of about 80,000 daltons was present in the spleen sample (lane 5), but not in that of kidney (lane 6). A broad ˜50,000 dalton band representing IgG chains was seen in both samples. In FIG. 7B, protein extracts of 35 S-methionine-labeled COS cells transfected with the MARCO cDNA (MARCO) or the same cDNA in the opposite orientation (control) were immunoprecipitated with MARCO antiserum, electrophoresed and processed for autoradiography. After a 4-hour pulse the immunoprecipitate migrated as a 210,000 dalton protein doublet under nonreducing conditions on 5% SDS-PAGE (lane 1). After reduction the major band had a size of about 60,000 daltons, with additional bands corresponding to differentially glycosylated forms of up to 80,000 daltons were also present (lane 3). After 18 hrs chase two bands of 70,000 daltons and a doublet of about 80,000 daltons remained (lane 4). Incubation with Tunicamycin revealed a band of 50,000 daltons (lane 5). No specific protein was precipitated from control samples (lanes 2 and 6). FIGS. 8A-8F illustrate binding of fluorescein-labeled E. coli , S. aureus and Zymosan A (S. cerevisiae) bacteria to MARCO receptors on cells transfected with full-length cDNA. Transfected COS cells or IC-21 macrophages were incubated with FITC-labeled S. aureus (A, D), E. coli (B, E) and Zymosan A (C, F) and the MARCO expressing COS cells were visualized by immunostaining with MARCO antibodies and a rhodamine labeled secondary antibody. The IC-21 cells were stained with ethidium bromide. MARCO positive COS cells, but not negative control COS cells showed specific binding of E. coli and and S. areus (A, B), while these cells did not bind Zymosan A (S. cerevisiae) (C). In contract, the IC-21 macrophages bond all three probes (D,E,F). This binding was shown to be specific as it could be inhibited by incubation of the cells prior to the addition of the labeled bacteria (E). FIG. 9 illustrates how antibodies against the extracellular domains IV and V of MARCO inhibit the biding of FITC-labeled Staphylococcus aureus bacteria to COS cells transfected with full-length MARCO cDNA and expressing native MARCO receptor. FIGS. 10A-10B show binding of DiI-labeled AcLDL to COS cells expressing the MARCO receptor. The MARCO expressing cell were incubated with DiI-AcLDL (5 μg/ml) and visualized with MARCO antiserum and a FITC-labeled secondary antibody. Immunopositive COS cells (A) readily bound DiI-AcLDL (B). DETAILED DESCRIPTION OF THE INVENTION The applicants have discovered a novel gene encoding for a previously unknown protein. The DNA-derived amino acid sequence of the protein is unique, not existing in the available data bases. The protein is a novel murine plasma associated protein expressed postnatally by subpopulations of macrophages. The new polypeptide chain (SEQ ID NO: 2), which was shown to be a one of three, presumably identical subunit chains of a macrophage membrane receptor with a collagenous structure, has been designated as "MARCO" for macrophage receptor-collagenous. The MARCO polypeptide chain was discovered by the isolation and nucleotide sequencing of cDNA clones which were identified during the screening of a mouse macrophage cDNA library with a human type XIII collagen DNA probe. This screening yielded several overlapping clones coding for a previously undescribed collagenous sequence, and rescreening of the same library with one of the cDNA inserts yielded new clones one of which, Maf-6 (FIG. 1), spanned a 1.8 kb sequence. The sequence of Maf-6 (SEQ ID NO: 1) contained a 159 bp 5'-end untranslated region, a 1554 bp open reading frame, followed by an over 156 bp 3'-end untranslated region containing a TGA translation stop codon, a putative AATAAA polyadenylation signal and a poly(A) tail (FIGS. 1 and 2). The sequence surrounding the putative initiator methionine codon ATG does not agree completely with the Kozak consensus sequence, but it can be designated as strong translation initiation site when considering positions -3 and +4 (Kozak, M., The scanning model for translation: An update, J. Cell. Biol. 108, 229-241 (1989)). Analysis of the 1554 bp open reading frame predicted the sequence for a unique 518 residue polypeptide not existing in the data base (FIG. 2). The molecular weight of this polypeptide chain was calculated to be 52,738. The amino acid sequence indicated the presence of several distinct domains. The open reading frame starts with an ˜50-residue rather hydrophilic domain I which starts with the initiator methionine and contains one cysteine. See FIGS. 2 and 3. Therefore, this protein does not contain a hydrophobic signal peptide-like sequence characteristic for secreted proteins. Domain II has an ˜25-residue hydrophobic sequence, which is followed by a hydrophilic domain III containing 75 residues, including two cysteine residues. Domain III also has two putative N-glycosylation sites (FIG. 2). The sequences of domains I, II and III are each unique. Domain IV has a 270-residue collagenous sequence characterized by 89 Gly-Xaa-Yaa triplets interrupted at one location (residues 174-176) by the sequence Ala-Glu-Lys. The C-terminal globular domain V which has 99 residues, six of which are cysteine. The sequence of this domain showed 48.9% sequence identity with the C-terminal domain of scavenger receptor type I (Krieger and Hertz, 1994). With the exception of the collagenous domain IV, the other domains did not show significant homology with scavenger receptors or other known proteins. As indicated above, the novel collagenous macrophage receptor with collagenous structure described here is referred to by the applicants as MARCO. Since the initial cDNA clones for MARCO were isolated from a macrophage cDNA library, the applicants examined if the protein is expressed in some other cells or tissues. In order to obtain an overall picture of the spatial expression of MARCO, Northern analyses were first carried out on RNA isolated from several mouse tissues, freshly isolated peritoneal macrophages and cultured cells. Using mRNA from adult mice, strong signals were observed with RNA from spleen and peritoneal macrophages, but not in other tissues, including liver (data not shown). In order to more exactly determine the sites of MARCO expression, in situ hybridization was carried out on whole different age embryos and tissues from newly born and adult mice. The results showed no signals above background in the embryonic tissues (data not shown), but strong signals were seen with a MARCO antisense probe in a highly region-specific manner, both in spleen and lymph nodes (FIG. 4). Signals above background were not seen with the same probe in other tissues such as lung and liver, which are normally rich in macrophages (data not shown). The signals observed in the spleen were localized to macrophage-like cells in the marginal zone at the interface of the white and red pulps (FIG. 4A, B). In lymph nodes strong signals were seen in cells of the medullary region which is rich in macrophages (FIG. 4G, H). Similar anlyses with a sense probe did not reveal positive signals in any of the tissues studied (not shown). The applicants also examined if MARCO is expressed in established macrophage cell lines using Northern analysis with mRNA isolated from a cultured macrophage cell line IC-21 (ATCC TIB 186), and the results revealed intense expression of an about 1.8 kb transcript (not shown). In order to determine where the MARCO protein is located in vivo, antibodies were raised for immunohistological analyses. The putative extracellular globular domains IV and V and intracellular domain I of the MARCO polypeptide chain were expressed as glutathione S-transferase (GST) fusion proteins in the pGEX-1λT vector in E. coli, as described in Examples below, and then purified and used as antigens to raise antisera in rabbits. Immunostaining of frozen 2-month-old mouse spleen tissues revealed specific staining in macrophages located in the same region of the marginal zone (FIG. 4C) where expression was observed by in situ hybridization (FIG. 4A, B). This indicates that MARCO is directly associated with the cells and not deposited into the extracellular matrix. Both antibodies gave identical results. No positive staining was observed in liver which is rich in scavenger receptor containing macrophages, indicating that the antibodies do not cross-react with the scavenger receptors. Based on the immunohistochemical data, a close relationship was observed in the spleen between the expression of MARCO and the marginal zone macrophage marker ER-TR9 (Dijkstra, C. D., Van Vliet, E., Dopp, E. A., Van der Lelij, A. A., and Kraal, G., Marginal zone macrophages identified by a monoclonal antibody: characterization of immuno- and enzyme-histochemical properties and functional capasities, Immunology 55, 23-28 (1985)). In the splenic marginal zone practically complete overlap was seen between the two macrophage markers (FIG. 4 C, D, E), and a similar correlation could be found for the expression of the two molecules in medullary macrophages in lymph nodes (not shown). Immunohistological staining of lymph node tissue with both MARCO antibodies stained macrophages located in medullary cords (not shown) in accordance with the expression pattern obtained with the in situ hybridization riboprobe (not shown). This correlates completely with the expression of ER-TR9 as previously reported (Dijkstra et al., 1985). The following experiments (for more specificity, see the Examples below) were carried out by the applicants to determine the orientation of MARCO on the macrophage plasma membrane. First, cultured transformed IC-21 macrophages shown to normally express MARCO were processed for field emission scanning electron microscopy (FESEM) of the cell surface and reacted with the antisera against the putative extracellular C-terminal or intracellular N-terminal domains made by the applicants, followed by incubation with a gold-labeled second antibody. The antibody against the C-terminal domain V readily bound to the cell surface (FIGS. 5A and 5B), while the antibody against the N-terminal domain I did not (data not shown). The antibodies decorated the cell surface quite evenly and they also bound strongly to pseuodopodia which could protrude quite long distances from the cell membrane. In a second set of experiments transmission immunoelectron microscopy was carried out with the antibodies and this revealed that MARCO is associated with the plasma membranes. Together, these results demonstrated that MARCO is a membrane protein, and that within the plasma membrane domain I is located intracellularly and domain V extracellularly. In a third experiment carried out to examine the orientation of MARCO in the plasma membrane, antisera against domains I or IV and V were injected intravenously into mice, after which the tissues were processed, cryosectioned and analyzed for staining using an FITC-conjugated second antibody. In the spleen the strong staining was observed in marginal zone macrophages when the antiserum against domain V was used (FIG. 6), whereas no staining was observed in spleen sections of mice injected with the antiserum against domain I (data not shown). Also, other tissues such as liver were negative in this experiment, indicating that the protein is mainly present in spleen. These results support the hypothesis that the N-terminal domain I, and C-terminal domains IV and V are intracellular and extracellular, respectively. It could be hypothesized that MARCO is a trimeric protein with a triple-helical domain similar to those in collagenous proteins, based on the fact that the MARCO subunit chain contained a 270-residue long Gly-Xaa-Yaa-repeat containing sequence. Furthermore, the presence of several cysteines in the polypeptide suggested that the chains might be disulfide-linked in such a trimer. In order to examine this, the applicants extracted protein from intact mouse spleen and kidney (negative control) tissues, and carried out immunoprecipitation with the antibodies against domains I or V of MARCO, followed by immunoblotting as more particularly described in the Examples below. This study revealed that when the spleen extract was immunoprecipitated, electrophoresed on a 5% gel without reduction and immunoblotted, a major band of about 210,000 daltons and a second slightly smaller, weaker band, were seen with both antibodies (FIG. 7A lanes 1 and 2). A broad band of about 160,000 daltons representing IgG was also present. These bands disappeared when the samples were electrophoresed after reduction, while one diffuse major band of about 80,000 daltons and one weaker, slightly smaller band appeared (FIG. 7A lane 5). In addition, a strong 50,000 dalton band representing IgG was present. No specific protein was precipitated from the kidney extract with the MARCO antibodies (FIG. 7A, lanes 3, 4 and 6). These results strongly suggest that the MARCO molecule has a trimeric conformation containing interchain disulfide bonds. The nature of the weaker, smaller bands is not sure, but since they were recognized by both antibodies, they might represent forms with different post-translational modifications. The applicants carried out further characterization of the MARCO protein using by metabolic labeling of transfected COS cells. COS cells, which normally do not express MARCO, were transfected with full-length cDNA to study glycosylation of the chains and also if native MARCO trimers can be formed with a single type of chains. Furthermore, labeling studies were carried out in the presence of Tunicamycin in order to examine if the minor heterogeneity of specifically immunoprecipitated bands might be due to differences in degree of glycosylation. Incubation with Tunicamycin, which inhibits N-glycosylation, revealed a MARCO chain with a size of ˜50,000 daltons which agrees well with the calculated size based on the amino acid sequence predicted from the cDNA (FIG. 7B, lane 5). In pulse-chase experiments, cells were first pulsed for 1 or 4 hours and the label was then chased for up to 18 hours. After the pulse the major band had a size of about 60,000 daltons, but additional specifically immunoprecipitated bands had sizes of up to 80,000 daltons after reduction (FIG. 7B, lane 3). After 18 hours chase the 60,000 dalton bands had disappeared, but two bands of 70,000 daltons and a doublet of about 80,000 remained (FIG. 7B, lane 4). These results suggest that the microheterogeneity of sizes of the subunit chains of MARCO is due to differences in glycosylation, but not proteolysis as these proteins were detected with antibodies reacting with both ends of the polypeptide (data not shown). Pulse-labeled immunoprecipitated MARCO extracted from the transfected cells was electrophoresed on SDS-PAGE without reduction and compared with MARCO immunoprecipitated from a spleen tissue extract. The results showed that the sizes of trimeric MARCO proteins from the COS cells (FIG. 7B, lane 1) and spleen (FIG. 7A, lanes 1 and 2) corresponded to each other. COS cells transfected with a construct containing MARCO cDNA in the wrong orientation did not reveal specific bands after immunoprecipitation (FIG. 8B, lanes 2 and 6). Together, the labeling data demonstrated that the transfected cells were able to synthesize single MARCO chains and assemble them into disulfide-bonded homotrimers. The applicants also studied if the homotrimers are transported to the plasma membrane using immunoelectron microscopy and this revealed staining for the MARCO chain mainly in plasma membranes of the transfected cells, indicating that the trimer was actually integrated into the plasma membrane (data not shown). The marginal zone macrophages in the spleen have been proposed to play a key role in the host-defense system by recognizing and phagocytosing blood pathogens such as bacteria and yeast. For example, the cells can selectively take up neutral polysaccharides present on bacterial walls. To initially characterize the potential binding properties of MARCO, cultured transfected COS cells, and IC-21 macrophages used as positive control cells, were incubated with several fluorescein-labeled bioprobes. When transfected COS cells expressing MARCO were incubated with labeled E. coli and S. areus bacteria, specific binding was seen to cells which were immunopositive with MARCO antibodies (FIG. 8A, B). In contrast, labeled S. cerevisiae (Zymosan A) did not bind to COS cells expressing MARCO (FIG. 8C). Cultured IC-21 macrophages bound all three probes (FIG. 8D-F). As negative control, COS cells transfected with a plasmid containing MARCO cDNA in the wrong orientation did not bind any of the probes (not shown). The binding of S. areus could be inhibited efficiently by antiserum (not shown) and IgG (FIG. 9) raised against domains IV and V. Binding of E. coli could also be inhibited by these antibodies (not shown). Due to the structural homology of MARCO with macrophage scavenger receptors which bind a variety of ligands such as acetylated LDL, the applicants also investigated if MARCO cDNA transfected COS cells bind this compound. The results showed that MARCO expressing COS cells readily bound DiI-acetylated LDL (FIG. 10). Accordingly, applicants' study provides the first description of a unique plasma membrane-bound macrophage receptor with collagenous structure (MARCO) expressed in specific subpopulations of macrophages in spleen, lymph nodes as well as in peritoneum. This receptor was shown to bind both gram positive and negative bacteria and acetylated LDL, but not yeast. The structure of MARCO resembles to some extent that of scavenger receptor type I (Kodama, T. Freeman, M., Rohrer, L., Zabrecky, J., Matsudaira, P., and Krieger, M., Type I macrophage receptor contains α-helical and collagen-like coiled coils, Nature 343,531-535 (1990)) which also is a macrophage specific protein. However, MARCO is clearly a distinct gene product with somewhat different binding properties than the scavenger receptor. In addition, the following observations were also concluded from applicants' study: A) MARCO (SEQ ID NO: 2) is a Membrane-Bound Trimeric Protein Based on the deduced amino acid sequence of the MARCO polypeptide which contains a 270-residue Gly-Xaa-Yaa-repeat sequence, it could be predicted that MARCO is a trimeric protein where this domain folds into a triple helix similar to that of collagens. This assumption gained support by experiments showing that MARCO extracted from both spleen tissue and transfected COS cells had a molecular weight of about 210,000 on SDS-PAGE without reduction. These experiments also demonstrated that the subunit chains are disulfide-bonded. The calculated molecular weight of a MARCO trimer containing unprocessed chains would be 160,000, but glycosylation of one or both of the two potential glycosylation sites in the MARCO polypeptides could explain a molecular weight of over 200,000 as determined by SDS-PAGE. The pulse-chase and Tunicamycin labeling studies carried out in this study supported this assumption. As the collagenous sequence of the MARCO chain is interrupted at one site by the sequence Ala-Glu-Lys close to the N-terminal end of the collagenous domain, the triple helix of domain IV in MARCO is likely to have a "kink" or "hinge" as has been shown to be the case in collagens with interrupted triple helices such as type IV collagen (Hudson, B. G., Reeders, S. T., and Tryggvason, K., Type IV collagen: Structure, gene organization and role in human diseases. Molecular basis of Goodpasture and Alport syndromes and diffuse leiomyomatosis, J. Biol. Chem. 15, 26033-26036, (1993)). At the present, it is not known if the MARCO molecules in vivo are homo- or heterotrimers, but applicants' experiments demonstrated that homotrimers can be formed in transfected COS cells from the MARCO subunit chain cloned in this study. The primary structure of MARCO is that it is not a secreted protein, as it does not contain a typical signal peptide sequence as in the case for the scavenger receptors. The hydrophobic sequence of domain II which resembles that of the single transmembrane domain of the scavenger receptor chains further indicated that MARCO is a membrane protein and this was confirmed in various immunological studies which clearly localized the protein to the plasma membrane, but also to intracellular membranes. The fact that grains were seen in association with intracellular membranes in immunoelectron microscopy may not necessarily mean that MARCO functions intracellularly, as it is possible that the intracellular membrane association is due to newly synthesized MARCO which is being transported out of the cell or, alternatively, internalized MARCO. B. MARCO Shows Structural Similarities with Scavenger Receptor Type I The primary structure of the MARCO subunit chain characterized here has higher similarity with the scavenger receptor chains than with any of the chains of structural collagens or other proteins with collagenous domains, including C1q, conglutinin, mannose binding proteins, pulmonary surfactant associated proteins, acetyl cholinesterase and bacterial pullulanase (Reid, K. B. M., Lowe, D. M., and Porter, R. R., Isolation and characterization of Clq, subcomponent of the first component of complement from human and rabbit sera, Biochem. J. 130, 749-763 (1972); Mays, C. and Rosenberry, T. L., Characterization of pepsin-resistant collagen-like tail subunit fragments of 18S and 14S acetylcholinesterase from Electrophorus electricus, Biochemistry 20, 2810-2817 (1981); Drickamer, K., Dordal, M. S., and Reynolds, L., Mannose-binding proteins isolated from rat liver contain carbohydrate-recognition domains linked N collagenous tails, J. Biol. Chem. 261, 6878-6887 (1986); Charalambous, B. M., Keen, J. N., and McPherson, M. J., Collagen-like sequences stabilize homotrimers of a bacterial hydrolase, EMBO J. 7, 2903-2909 (1988); Lee, Y.-M., Leiby, K. R., Allar, J., Paris, K., Lerch, B., and Okarma, T. B., Primary structure of bovine conglutinin, a member of the C-type animal lectin family, J. Biol. Chem. 266, 2715-2723 (1991); Krejci, E., Coussen, F., Duval, N., Chatel, J.-M., Legay, C., Puype, M., Vandekerckhove, J., Cartaud, J., Bon, S., and Massoulie, J., Primary structure of a collagenic tail peptide of Torpedo acetylcholinesterase: co-expression with catalytic subunit induces the production of collagen tailed forms in transfected cells, EMBO J. 10, 1285-1293 (1991); Petry, F., Reid, K., and Loos, M., Isolation sequence analysis and characterization of cDNA clones coding for the C chain of mouse, Clq. Eur. J. Biochem. 209,129-134 (1992). Furthermore, the predicted tertiary structure (FIG. 3) and the polarity of amino acids next to the hydrophobic domain II strongly indicate that MARCO is, indeed, an integral trimeric membrane molecule, where each chain has a single membrane-spanning domain and an N-terminal cytoplasmic domain I as in the scavenger receptor. The orientation of MARCO was verified by immunohistochemical and FESEM analyses which clearly demonstrated that domain V is extracellular and domain I intracellular. In addition, it has been determined that the 75-residue extracellular domain III of the MARCO chain which corresponds to the 33-residue domain III in the scavenger receptor chains, probably participates in a "spacer" domain between the plasma membrane and the rod-like triple-helical domain IV of MARCO. The triple-helical domain IV of MARCO differs substantially from the coiled coil region formed by domains IV and V of the scavenger receptor. Domain IV of MARCO forms a triple-helical collagenous domain interrupted at one site by an Ala-Glu-Lys sequence, while the scavenger receptor has first a noncollagenous α-helical coiled coil followed by a classical collagenous triple helix which, however, is considerably shorter than that of MARCO. The C-terminal end domains V and VI of MARCO and scavenger receptor type I, respectively, are quite homologous, each containing six cysteine residues with similar spacing. This scavenger receptor cysteine-rich motif (SRCR domain) has been found in a number of other proteins. All of the known mammalian SRCR-domain-containing proteins are expressed on the surfaces of cells associated with the immune system and host defence functions (T cells, B cells and macrophages) or are secreted and known or suspected of being involved with host defence (Resnick, D., Pearson, A., and Krieger, M., The SRCR superfamily: a family reminiscent of the Ig superfamily, Trends Biochem. Sci. 19, 5-8 (1994)). As can be seen in FIG. 11, this sequence is highly conserved between MARCO and scavenger receptor, the sequence identity being 48.9% and sequence similarity 61.5% when conserved amino acid substitutions are taken into account. C. Expression of MARCO in a Subset of Macrophages and Binding of Bacteria Indicates Role in Host Defense The expression of MARCO in specific macrophage subpopulations in lymphoid organs only is indicative of a role for MARCO in immunological reactions. It also emphasizes the heterogeneity within macrophage populations and the compartmentalization of the lymphoid system. The marginal zone macrophages of the spleen in which MARCO is highly expressed form, in many respects, a very special population. These large macrophages are strategically positioned in the anatomical compartment of the spleen where the bloodstream leaves the small arterioles into the "open" venous system (Kraal, G., Ter Hart H., Meelhuizen, C., Venneker, and Claassen, E., Marginal zone macrophages and their role in the immune response against T-independent type 2 antigens. Modulation of the cells with specific antibody, Eur. J. Immunol. 19, 675-681 (1989)). Here, in the marginal zone, the first contact of the phagocytosing system with blood borne pathogens takes place, and especially the highly phagocytic marginal zone macrophages can take up material, even without the need of prior opsonization. Despite structural similarities with scavenger receptor type I, the MARCO molecule probably has different functions as it is present in different types of macrophages. For example, MARCO was not found in liver or lung tissues. However, as scavenger receptors, MARCO binds acetylated LDL and bacteria, but it differs by not binding yeast. The restricted expression of the MARCO receptor on macrophages capable of binding and possibly taking up acetylated LDL and located at sites in the spleen where they are in continuous contact with the blood stream points to a significant role in the clearance of serum components. Taken together, the restricted expression of MARCO in subpopulations of macrophages which are involved in the uptake of (bacterial) antigenic polysaccharides, and the structural similarities with scavenger receptors indicate that MARCO plays an important role in the host defense system and homeostasis of the body. The following examples further illustrate the specific embodiments of the present invention. It is to be understood that the present invention is not limited to the examples, and various changes and modifications may be made in the invention without departing from the spirit and scope thereof. EXAMPLES A. Experimental Procedures Isolation and Characterization of cDNA Clones Coding For the Murine MARCO Polypeptide Chain A mouse macrophage cDNA library in λgt11 (Clontech ML1005) was screened with a human type XIII collagen DNA. Clones were screened to purity with 32 P-labeled probes at low stringency conditions at +37° C. in 5×SSC, 5×Denhart's, 0.1% SDS, 50% formamide, 200 mg/ml salmon sperm DNA. Filters were washed with 0.2×SSC, 0.1% SDS at +42° C. Positive clones were isolated and subcloned into pUC18/19- or M1318/19-vectors with standard methods, and sequenced from both strands with the dideoxynucleotide chain-termination procedure using Sequenase enzyme (United States Biochemicals). Either universal primers or specific oligonucleotide primers were used in the sequencing. RNA Isolations and Northern Analysis Total RNA from tissues (liver, kidney, spleen, lung, brain and thymus) of about 2-month-old (adult) mice was extracted (Chomeczynski, P., and Sacchi, N., Single step method of RNA isolation by acid quanidium thiocyamate phenol chloroform extraction, Anal. Biochem. 162, 156-159, (1987)). mRNA was isolated directly from cultured cells or from total RNA with a slight modification of the Fast Track RNA isolation kit method (Invitrogen) by oligo dT cellulosa (Pharmacia). For Northern analysis mRNA was electrophoresed on a 1.0% agarose gel in the presence of formaldehyde. The RNA was transferred to nitrocellulose filters, which were hybridized with a MARCO cDNA insert labeled with 32 P-dCTP by random priming. Prehybridization and overnight hybridization were done at +42° C. in 5×SSC, 5×Denhart's, 0.1% SDS, 50% formamide, 200 mg/ml salmon sperm DNA solution. Membranes were washed in 2×SSC, 0.1% SDS +42° C. In Situ Hybridization In situ hybridization was carried out on whole 14 to 17 day-old mouse embryos and on lung, liver spleen, lymph nodes, kidney and heart tissues of 9-day-old pups, as well as on bone marrow, intestine, lung, liver, spleen, lymph nodes, kidney and thymus of adult mice. Tissues were dissected in phosphate-buffered saline, pH 7.3 and fixed in paraformaldehyde at +4° C. for 1 h or overnight, dehydrated, and embedded in paraffin wax. Sections of 7 μm were placed on silanized glass slides and stored at +4° C. until used. For the preparation of RNA probes, DNA fragments (nucleotides 65-398 and 2211-1672 in FIG.2) were amplified by PCR using the Maf-6 cDNA clone as template. PCR primers contained restriction sites for subcloning into pSP64 and pSP65 plasmid vectors (Promega). The labeling of probes and in situ hybridization were performed (Wilkinson, D. G., and Green, J., In situ hybridization and the three dimensional reconstruction of serial sections. In Postimplantation mammalian embryos, A. J. Copp and D. L. Cockroft, eds. (Oxford: OUP), pp. 155-171 (1990)). Briefly, the plasmids were first linearized and 35 S!-UTP -labeled (1000 Ci/nmol, Amersham) probes were transcribed from the SP6 promoter. The probes were fractionated with Sephadex G-50 (Pharmacia), precipitated with ethanol, mixed with hybridization mixture, and placed on the pretreated sections. The sections were incubated overnight at +50° C., washed under high stringency condition, and dipped in autographic emulsion (Kodak NTB2). After exposure for 11 days, the emulsion was developed and the sections were stained with hematoxylin and mounted. Preparation of Antibodies Monoclonal antibodies, ERTR-1 and MOMA-1, against macrophage antigens have previously been described (Dijkstra, C. D., Van Vliet, E., Dopp, E. A., Van der Lelij, A. A., and Kraal, G., Marginal zone macrophages identified by a monoclonal antibody: characterization of immuno- and enzyme-histochemical properties and functional capasities, Immunology 55, 23-28 (1985); Kraal, G., Ter Hart H., Meelhuizen, C., Venneker, and Claassen, E., Marginal zone macrophages and their role in the immune response against T-independent type 2 antigens. Modulation of the cells with specific antibody, Eur. J. Immunol. 19, 675-681 (1989)). For the production of polyclonal antibodies domains of the MARCO polypeptide were expressed as glutathione S-transferase (GST) fusion proteins in the pGEX-1λT vector (Pharmacia) in E. coli. DNA fragments encoding the putative extracellular domain IV and V (residues 369-518, FIG. 2) and intracellular domain I (residues 1-50, FIG. 2) of the MARCO polypeptide were generated by polymerase chain reaction (PCR) using primers containing restriction sites for cloning into the pGEX-1λT vector (Pharmacia). Sequences were confirmed by DNA-sequencing. Fusion proteins produced in bacteria were purified using glutathione Sepharose 4B (Pharmacia) and eluted with 5 mM glutathione. Purified MARCO polypeptides were mixed with Freund's adjuvant (Difco), and used for immunization of rabbits. Antisera were used after the third booster. IgGs were first purified by protein A Sepharose (Pharmacia) and then further purified by negative immunoabsorption from unspecific antibodies against the GST-protein and E. coli proteins using GST-E. coli total protein lysate coupled to CNBr-activated Sepharose 4B (Pharmacia). Immunohistochemical Staining Light microscopy immunohistochemical analyses were carried out on cryosections of mouse tissues. The sections were fixed in ethanol or acetone, air-dried and then used for immunostaining using either peroxidase or fluorescence dyes. For staining with monosclonal antibody against the macrophage marker ER-TR9 (Kraal, G., Ter Hart H., Meelhuizen, C., Venneker, and Claassen, E., Marginal zone macrophages and their role in the immune response against T-independent type 2 antigens. Modulation of the cells with specific antibody, Eur. J. Immunol. 19, 675-681 (1989)), sections were incubated with the antibody for 1 h at 4° C., washed twice with PBS and incubated with horse radish peroxidase (HRP)-conjugated rabbit anti-rat IgG second antibody (Dako, Denmark). After washing HRP activity was demonstrated with amino-ethyl carbazole (AEC) and H 2 O 2 for 4 min., resulting in a red reaction product. For double staining the sections were thereafter incubated with rabbit anti-MARCO peptide antiserum against extracellular domain IV and V for 1 h at 4° C., washed and incubated with a swine anti-rabbit IgG-HRP conjugate (Dako, Denmark), HRP activity was now demonstrated using 4-chloro-1-naphtol and H 2 O 2 for 4 min., resulting in a blue reaction product. Immunolocalization For staining with monoclonal antibody against the macrophage marker ER-TR9 (Kraal, 1992), crysections were first incubated with the antibody, and then with horseradish peroxidase (HRP)-conjugated rabbit anti-rat IgG second antibody (Dako, Denmark). HRP activity was demonstrated with amino-ethyl carbazole (AEC) and H 2 O 2 , resulting in a red reaction product. For double staining the sections were thereafter incubated with rabbit anti-MARCO IgG (100 μg/ml) against domains I or V and incubated with a swine anti-rabbit IgG-HRP conjugate (Dako, Denmark). HRP activity was now demonstrated using 4-chloro-1-naphtol and H 2 O 2 , resulting in a blue reaction product. For immunofluorescence microscopy sections were incubated with anti-MARCO IgG (100 μg/ml) and then with FITC-conjugated goat anti-rabbit IgG (Cappel). For field emission electron microscopy cells were fixed with 4% and 8% paraformaldhyde for 10 min each, followed by incubation with anti-MACRO IgG anti-rabbit IgG labeled with 30 nm gold particles (Amersham). The cells were post-fixed with 2.5% glutaraldehyde, dehydrated in alcohol, dried in Balzers CPD 030 critical point dryer, coated with a thin carbon layer and examined in a Jeol JSM-6300 F electron microscope. Immunoprecipitation Immunoprecipitation was carried out with standard procedures (Sambrook, J., Fritsch, E. F., and Maniatis, T., Molecular Cloning: A laboratory Manual Second Edition. Cold Spring Harbor, N.Y., Cold Spring Harbor Laboratory Press (1989). Briefly, membranes were partially purified from mouse spleen and kidney (Schneider, W. J., Goldstein, J. L., and Brown, M. S., Partial purification and characterization of the low density lipoprotein receptor from bovine adrenal cortex, J. Biol. Chem. 255, 11442-11447 (1980)) and the membranes and cells were extracted into triple detergent buffer (50 mM Tris-HCl, pH 8, 150 mM NaCl, 1% Nonidet P-40, 0.1% SDS, 0.5% sodiumdeoxycholate, 100 mg/ml phenymethylsulfonyl fluoride (PMSF), 0.02% sodium azide, 1 mg/ml aprotinin). The extract supernates were then precleared by incubating with irrevelant serum followed by incubation with S. aureus cells (Fluka). The antigen was precipitated using polyclonal antisera or purified IgG against MARCO and incubated with protein A-Sepharose (Pharmacia). The protein A-sepharose-IgG complex was washed with NET buffer (50 mM Tris-HCl, pH 7.5, 150 mM NaCl, 0.1% Nonidet P-40, 1 mM EDTA, pH 8, 0.25% gelatin and 0.02% sodium azide) and then with 10 mM Tris-HCl, pH 7.5, 0.1% NP-40 solution, and heated in sample buffer at 95° C. in the presence or absence of 5% mercaptoethanol prior SDS-PAGE. SDS-PAGE and Western Analysis Reduced and nonreduced samples were separated by electrophoresis on 8% or 5% SDS polyacrylamide gels (Laemmli, U. K., Cleavage of structural proteins cluring the assembly of the head of bacteriophage T4, Nature 227, 680-685 (1970)). Gels with radioactive protein samples were impregnated in EN 3 HANCE (Du Pont) before drying and exposure to film at -70° C. For Western analysis, gels were electroblotted onto Immobilon P membrane (Millipore), using semidry method (Biometra Fast Blot B33). Following electrophoresis the membranes were blocked with 3% milk powder in TBS buffer (25 mM Tris-HCl, pH 7.4, 137 mM NaCl, 2.7 mM KCl) followed by incubation with MARCO antiserum diluted 1:50-1:100 in TBS buffer. After washings with TBS buffer the membranes were incubated with alkaline-phosphatase-conjugated anti-rabbit IgG (Sigma), washed and developed with nitroblue tetrazolium/5-bromo-4-chloro-3-indolyl phosphate. Cell Culture, Transfections and Metabolic Labeling Cell lines IC-21 and COS-7 were from ATCC. IC-21 cells were grown in RPMI 1640 medium and COS-7 cells in high glucose (4.5 g/l) Dulbecco's Modified Eagle's medium (Gibco laboratories) both mediums were supplemented with 10% fetal calf serum, 2 mM L-glutamine, 100 IU/ml penicillin, and 75 mg/ml ascorbate. For cell transfections, a cDNA fragment containing the entire coding region of MARCO with the authentic translation initiation sequence was generated by oligonucleotide-primed polymerase chain reaction and its sequence was confirmed by DNA-sequencing. The product was cloned into the pSG5 expression vector (Green, S., Isseman, I., and Sheer, E., A versatile in vivo and in vitro eukaryotic expression vector for protein engineering, Nucl. Acid. Res. 16, 399 (1988)) using Bgl II restriction sites engineered into the primers. Additionally, a construct made with a 5'-PCR primer containing an additional consensus sequence GCCGCCACCATGG (Kozak, M, The scanning model for translation: An update. J. Cell. Biol. 108, 229-241 (1989)) was made for more effective initiation of translation. A construct containing the coding region in the opposite orientation (3'-5') was used as a control. A day before transfection, COS-7 cells were plated at 0.7×10 6 cells per 90 mm tissue culture dish. The cells were transfected overnight by the calcium phosphate method (Gorman, C., High efficiency gene transfer into mammalian cells. In DNA cloning, Volume II, A practical approach, D. M. Glover, ed (Oxford: IRL press), pp. 143-161 (1985)) using 20 μg DNA isolated with CsCl gradient centrifugation. After 18 hrs the calcium phosphate precipitate was removed, and cells used for immunostaining or binding assays were harvested with trypsin and replated. For metabolic labeling cells were incubated for 1 hr or 4 hrs in methione-free DMEM medium containing 200 μCi/ml ( 35 S)methionine (Amersham>1000 Ci/mmol) and 10% dialysed FCS. The cells were then chased for 0, 3, 8 or 18 hrs in medium supplemented with unlabeled methionine. Following the pulse-chase label, the cells were washed with PBS buffer and then used in the immunoprecipitations. In N-glycosylation inhibition studies 3 mg/ml Tunicamycin was included in the medium 3 hrs before labeling and during the 4 hrs labeling period. Studies of Ligands Binding to the MARCO Receptor and Inhibition of Binding With MARCO Antibodies For binding studies, IC-21 macrophages (positive control) and transfected COS cells cultured on coverslips were incubated in the culture medium at +37° C. with fluorescent labeled ligand candidates (Molecular Probes Inc); with FITC-labeled BioParticles, Escherichia coli, Staphylococcus aureus and Zymosan A (Saccharomyces cerevisiae) for 1 hour, and with DiI (1,1'-dioctadecyl-3,3,3',3'-tetramethyl-indocarbocyanine perchlorate)-labeled AcLDL (5 mg/ml) for 3-5 hrs. Bio Particles and cells were incubated in 50:1-100:1 ratios. In the Zymosan A binding studies higher particle amounts and longer incubation times were also tested. Following incubation the cells were rinsed five times with PBS solution, fixed with 4% paraformaldehyde or with ethanol for 10 minutes, and then immunostained using IgG against MARCO polypeptides and FITC- or rhodamine-labeled secondary antibodies as described in the immunofluorescence and confocal microscopy paragraph above. As negative controls, COS cells transfected with a plasmid containing cDNA in the wrong orientation were used. Binding inhibition studies were carried out by adding normal rabbit IgG and MARCO anti-rabbit IgG (25-500 μg/ml) or preimmune and anti-MARCO sera at 1/10-1/100 dilutions prior to the addition of ligands. Bound bacteria were counted from one hundred cells positive with anti-MACRO antibodies, each experiment being carried out in triplicates. B. Results cDNA Clones and Deduced Primary Structure Screening of a mouse macrophage cDNA library with a human type XIII collagen cDNA probe yielded several overlapping clones coding for a previously undescribed collagenous sequence. Screening of the same library with one of the cDNA inserts yielded new clones one of which, Maf-6, spanned a 1.8 kb sequence. This sequence contained an apparent 159 bp 5'-end untranslated region, a 1554 bp open reading frame, followed by over 156 bp 3'-end untranslated region containing a TGA translation stop codon, a putative AATAAA polyadenylation signal and a poly(A) tail (FIG. 2). The sequence surrounding the putative initiator methionine codon ATG does not agree completely with the Kozak consensus sequence, but it can be designated as strong translation initiation site when considering positions -3 and +4. Analysis of the 1554 bp open reading frame predicted the sequence for a unique 518 residue polypeptide not existing in the data base (FIG. 2). The molecular weight of this polypeptide chain was calculated to be 52,738. The amino acid sequence indicated the presence of several distinct domains. The open reading frame starts with an ˜50-residue hydrophilic domain I which starts with the initiator methionine and contains one cysteine. Therefore, this protein does not contain a hydrophobic signal peptide-like sequence characteristic for secreted proteins. Domain II has an ˜25-residue hydrophobic sequence, which is followed by a hydrophilic domain III containing 75 residues, including two cysteine residues. Domain III also has two putative N-glycosylation sites (FIG. 2). The sequences of domain I, II and III are each unique, with no significant homology with sequences in the EMBL and Swiss protein data bases. Domain IV has a 270-residue collagenous sequence characterized by 89 Gly-Xaa-Yaa triplets interrupted at one location (residues 174-176) by the sequence Ala-Glu-Lys. The C-terminal globular domain V which has 99 residues, six of which are cysteine. The sequence of this domain showed 48.9% sequence identity with the C-terminal domain of scavenger receptor type I. With the exception of the collagenous domain IV, the other domains did not show significant homology with scavenger receptors or other known proteins. Expression of MARCO The initial cDNA clones for MARCO were isolated from a macrophage cDNA library. In order to obtain an overall picture of the spatial expression of MARCO, Northern analyses were first carried out with RNA isolated from several tissues, freshly isolated peritoneal macrophages and cultured cells. Using mRNA from adult mice, strong signals were observed with RNA from spleen and peritoneal macrophages, but not in other tissues, including liver (data not shown). In situ hybridization was carried out on whole 14-17-day-old embryos and tissues from 2-month-old mice to assess more exactly which cells express MARCO in vivo. No signals above background were observed in the embryonic tissues (data not shown), but strong signals were seen with the MARCO antisense probe in a highly region-specific manner, both in spleen and lymph nodes (FIG. 4). In contrast, all other tissues examined, including lung and liver, which are rich in macrophages, did not show signals above background using the same probe (data not shown). The signals observed in the spleen were present in macrophage-like cells in the marginal zone at the interface of the white and red pulps (FIG. 4A, B). In lymph nodes strong signals were seen in cells of the medullary region which is rich in macrophages (FIG. 4G, H). Similar anlyses with a sense probe did not reveal positive signals in any of the tissues studied (not shown). To examine if MARCO is expressed in established macrophage cell lines, applicants carried out Northern analysis with mRNA isolated from a cultured macrophage cell line IC-21 (ATCC TIB 186). These cells exhibited intense expression of an about 1.8 kb transcript (not shown). Immunohistochemical Localization of MARCO to Macrophages In order to determine where the MARCO protein is located in vivo, antibodies were raised for immunohistological analyses. The putative extracellular globular domain V and intracellular domain I of the MARCO polypeptide chain were expressed as glutathione S-transferase (GST) fusion proteins in the pGEX-1λT vector in E. coli and then purified and used as antigens to raise antisera in rabbits. Immunostaining of frozen 2-month-old mouse spleen tissues revealed specific staining in macrophages located in the same region of the marginal zone (FIG. 4C) where we observed expression by in situ hybridization (FIG. 4A, B). This indicates that MARCO is directly associated with the cells and not deposited into the extracellular matrix. Both antibodies gave identical results. No positive staining was observed in liver which is rich in scavenger receptor containing macrophages, indicating that the antibodies do not cross-react with the scavenger receptors. Based on the immunohistochemical data a close relationship was observed in the spleen between the expression of MARCO and the marginal zone macrophage marker ER-TR9 (Dijkstra, C. D., Van Vliet, E., Dopp, E. A., Van der Lelij, A. A., and Kraal, G., Marginal zone macrophages identified by a monoclonal antibody: characterization of immuno- and enzyme-histochemical properties and functional capasities, Immunology 55, 23-28 (1985)). In the splenic marginal zone practically complete overlap was seen between the two macrophage markers (FIG. 4C, D, E), and a similar correlation could be found for the expression of the two molecules in medullary macrophages in lymph nodes (not shown). As can be seen from FIG. 4, expression of MARCO and ER-TR9 was not present in the macrophages lining the marginal sinus which normally express the MOMA-1 antigen (FIG. 4F). Immunohistological staining of lymph node tissue with both MARCO antibodies stained macrophages located in medullary cords (not shown) in accordance with the expression pattern obtained with the in situ hybridization riboprobe (FIG. 4G, H). This correlates completely with the expression of ER-TR9 as previously reported (Dijkstra et al., 1985). Immunolocalization and Orientation of MARCO on Macrophage Cell Surface Cultured IC-21 transformed macrophages were processed for field emission scanning electron microscopy (FESEM) of the cell surface and reacted with antisera against the putative extracellular C-terminal or intracellular N-terminal domains followed by incubation with a gold-labeled second antibody. The antibody against the C-terminal domain V readily bound to the cell surface (FIGS. 5A and 5B), while the antibody against the N-terminal domain I did not (data not shown). The antibodies decorated the cell surface quite evenly and they also bound strongly to pseuodopodia which could protrude quite long distances from the cell membrane. Transmission immunoelectron microscopy revealed gold particles particularly associated with the plasma membranes, but also to some extent in intracellular membranes (not shown). Together, these results demonstrated that MARCO is a membrane protein, and that within the plasma membrane domain I is located intracellularly and domain V extracellularly. In order to further examine the orientation of MARCO in the plasma membrane antisera against domains I or V were injected intravenously into mice, after which the tissues were processed, cryosectioned and analyzed for staining using an FITC-conjugated second antibody. In the spleen results revealed solely staining of marginal zone macrophages when the antiserum against domain V was used (FIG. 6), whereas no staining was observed in spleen sections of mice injected with the antiserum against domain I (data not shown). Other tissues such as liver were negative in this experiment. These results support the hypothesis that the N-terminal domain I and C-terminal domain V are intracellular and extracellular, respectively. MARCO Polypeptide Chains Form Disulfide-linked Trimers in Vivo The presence of a 270-residue long Gly-Xaa-Yaa-repeat containing sequence indicated that MARCO is a trimeric protein with a triple-helical domain similar to those in collagenous proteins. Furthermore, the presence of several cysteines in the polypeptide suggested that the chains might be disulfide-linked in such a trimer. In order to address this question, we extracted protein from intact mouse spleen and kidney (negative control) tissues, and carried out immunoprecipitation with the antibodies against domains I or V of MARCO, followed by immunoblotting (Sambrook, J., Fritsch, E. F., and Maniatis, T., Molecular Cloning: A laboratory Manual Second Edition. Cold Spring Harbor, N.Y., Cold Spring Harbor Laboratory Press (1989)) as described in Experimental Procedures. This study revealed that when the spleen extract was immunoprecipitated, electrophoresed on a 5% gel without reduction an immunoblotted, a major band of about 210,000 daltons and a second slightly smaller, weaker band, were seen with both antibodies (FIG. 7A lanes 1 and 2). A broad band of about 160,000 daltons representing IgG was also present. These bands disappeared when the samples were electrophoresed after reduction, while one diffuse major band of about 80,000 daltons and one weaker, slightly smaller band appeared (FIG. 7A lane 5). In addition, a strong 50,000 dalton band representing IgG was present. No specific protein was precipitated from the kidney extract with the MARCO antibodies (FIG. 7A, lanes 3, 4 and 6). These results strongly suggest that the MARCO molecule has a trimeric conformation containing interchain disulfide bonds. The nature of the weaker, smaller bands is not sure, but since they were recognized by both antibodies, they might represent forms with different posttranslational modifications. Characterization of MARCO by Metabolic Labeling of Transfected COS Cells COS cells, which normally do not express MARCO, were transfected with full-length cDNA to study glycosylation of the chains and also if native MARCO trimers can be formed with a single type of chains. Furthermore, labeling studies were carried out in the presence of Tunicamycin in order to examine if the minor heterogeneity of specifically immunoprecipitated bands might be due to differences in degree of glycosylation. Incubation with Tunicamycin, which inhibits N-glycosylation, revealed a MARCO chain with a size of ˜50,000 daltons which agrees well with the calculated size based on the amino acid sequence predicted from the cDNA (FIG. 7B, lane 5). In pulse-chase experiments, cells were first pulsed for 1 or 4 hours and the label was then chased for up to 18 hours. After the pulse the major band had a size of about 60,000 daltons, but additional specifically immunoprecipitated bands had sizes of up to 80,000 daltons after reduction (FIG. 7B, lane 3). After 18 hours chase the 60,000 dalton bands had disappeared, but two bands of 70,000 daltons and a doublet of about 80,000 remained (FIG. 7B, lane 4). These results suggest that the microheterogeneity of sizes of the subunit chains of MARCO is due to differences in glycosylation, but not proteolysis as these proteins were detected with antibodies reacting with both ends of the polypeptide (data not shown). Pulse-labeled immunoprecipitated MARCO extracted from the transfected cells was electrophoresed on SDS-PAGE without reduction and compared with MARCO immunoprecipitated from a spleen tissue extract. The results showed that the sizes of trimeric MARCO proteins from the COS cells (FIG. 9B, lane 1) and spleen (FIG. 7A, lanes 1 and 2) corresponded to each other. COS cells transfected with a construct containing MARCO cDNA in the wrong orientation did not reveal specific bands after immunoprecipitation (FIG. 7B, lanes 2 and 6). Together, the labeling data demonstrated that the transfected cells were able to synthesize single MARCO chains and assemble them into disulfide-bonded homotrimers. Studies on Binding Properties of MARCO The marginal zone macrophages in the spleen have been proposed to play a key role in the host-defense system by recognizing and phagocytosing blood pathogens such as bacteria and yeast. For example, the cells can selectively take up neutral polysaccharides present on bacterial walls. To initially characterize the potential binding properties of MARCO, cultured transfected COS cells, and IC-21 macrophages used as positive control cells, were incubated with several fluorescein-labeled bioprobes. When transfected COS cells expressing MARCO were incubated with labeled E. coli and S. aureus bacteria, specific binding was seen to cells which were immunopositive with MARCO antibodies (FIG. 8 A,B). In contrast, labeled S. cerevisiae (Zymosan A) did not bind to COS cells expressing MARCO (FIG. 8 C). Cultured IC-21 macrophages bound all three probes (FIG. 8 D-F). As negative control, COS cells transfected with a plasmid containing MARCO cDNA in the wrong orientation did not bind any of the probes (not shown). The binding of S. aureus could be inhibited efficiently by antiserum (not shown) and IgG (FIG. 9) raised against domains IV and V. Binding of E. coli could also be inhibited by these antibodies (not shown). Due to the structural homology of MARCO with macrophage scavenger receptors which bind a variety of ligands such as acetylated LDL, we also investigated if MARCO cDNA transfected COS cells bind this compound. The results showed that MARCO expressing COS cells readily bound DiI-acetylated LDL (FIG. 10). The invention has been described with reference to the preferred embodiment. Obviously, modifications and alterations will occur to others upon reading and understanding the preceding detailed description. It is intended that the invention be construed as including all such modifications and alterations insofar as they come within the scope of the appended claims or the equivalents thereof. __________________________________________________________________________SEQUENCE LISTING(1) GENERAL INFORMATION:(iii) NUMBER OF SEQUENCES: 2(2) INFORMATION FOR SEQ ID NO:1:(i) SEQUENCE CHARACTERISTICS:(A) LENGTH: 1868 base pairs(B) TYPE: Nucleic acid(C) STRANDEDNESS: Single(D) TOPOLOGY: Linear(ii) MOLECULE TYPE: Nucleotide-genomic DNA(iii) HYPOTHETICAL: Not relevant(iv) ANTI-SENSE: Not relevant(x) SEQUENCE DESCRIPTION: SEQ ID NO:1:TCCCCACAGCCAGGAAACATTGTGCAAATTGAAAAATCA39TTGCCAAAGGGAAGTTGTATGCATCTCCAGCTAGCTGCCGCAGTTAAATGGGAGCCCTGC99TTCCTCCTAGGGGAGAGTTTCTGCTGGCTCCAGGGCTTTGGCCACCTATAAAGCTTAGCA159ATGGGAAGTAAAGAACTCCTCAAAGAGGAAGACTTCTTGGGCAGCACA207METGLYSERLYSGLULEULEULYSGLUGLUASPPHELEUGLYSERTHR151015GAAGACAGAGCCGATTTTGACCAAGCTATGTTCCCTGTGATGGAGACC255GLUASPARGALAASPPHEASPGLNALAMETPHEPROVALMETGLUTHR202530TTCGAAATCAATGATCCAGTGCCCAAGAAGAGAAATGGGGGGACCTTC303PHEGLUILEASNASPPROVALPROLYSLYSARGASNGLYGLYTHRPHE354045TGCATGGCAGTCATGGCCATCCACCTGATCCTGCTCACGGCAGGTACT351CYSMETALAVALMETALAILEHISLEUILELEULEUTHRALAGLYTHR505560GCACTGCTGCTGATTCAAGTTCTCAATCTGCAGGAGCAGCTCCAGATG399ALALEULEULEUILEGLNVALLEUASNLEUGLNGLUGLNLEUGLNMET65707580CTAGAGATGTGCTGTGGCAATGGATCACTAGCTATCGAGGACAAGCCC447LEUGLUMETCYSCYSGLYASNGLYSERLEUALAILEGLUASPLYSPRO859095TTCTTCTCGCTGCAGTGGGCACCCAAAACACACCTGGTACCTAGAGCA495PHEPHESERLEUGLNTRPALAPROLYSTHRHISLEUVALPROARGALA100105110CAGGGGCTGCAAGCCTTGCAGGCCCAGCTCAGCTGGGTCCATACCAGC543GLNGLYLEUGLNALALEUGLNALAGLNLEUSERTRPVALHISTHRSER115120125CAGGAGCAACTCCGTCAGCAGTTCAACAACCTCACTCAAAATCCAGAG591GLNGLUGLNLEUARGGLNGLNPHEASNASNLEUTHRGLNASNPROGLU130135140TTGTTCCAGATTAAAGGTGAACGAGGCTCTCCAGGTCCAAAAGGGGCC639LEUPHEGLNILELYSGLYGLUARGGLYSERPROGLYPROLYSGLYALA145150155160CCGGGTGCTCCTGGAATCCCCGGGCTGCCTGGGCCAGCTGCTGAGAAG687PROGLYALAPROGLYILEPROGLYLEUPROGLYPROALAALAGLULYS165170175GGAGAAAAGGGGGCTGCAGGTCGTGATGGAACCCCAGGTGTCCAAGGA735GLYGLULYSGLYALAALAGLYARGASPGLYTHRPROGLYVALGLNGLY180185190CCCCAGGGCCCACCAGGCAGCAAGGGAGAGGCAGGCCTCCAGGGACTT783PROGLNGLYPROPROGLYSERLYSGLYGLUALAGLYLEUGLNGLYLEU195200205ACGGGTGCACCAGGGAAGCAAGGAGCAACTGGTGCTCCAGGACCTCGA831THRGLYALAPROGLYLYSGLNGLYALATHRGLYALAPROGLYPROARG210215220GGAGAGAAGGGCAGCAAAGGTGACATAGGTCTCACTGGCCCCAAGGGG879GLYGLULYSGLYSERLYSGLYASPILEGLYLEUTHRGLYPROLYSGLY225230235240GAACATGGCACCAAGGGAGACAAAGGGGACCTAGGCCTTCCAGGAAAC927GLUHISGLYTHRLYSGLYASPLYSGLYASPLEUGLYLEUPROGLYASN245250255AAAGGGGACATGGGCATGAAGGGAGACACGGGGCCCATGGGGTCCCCT975LYSGLYASPMETGLYMETLYSGLYASPTHRGLYPROMETGLYSERPRO260265270GGAGCTCAGGGAGGTAAAGGTGATGCTGGAAAACCAGGCCTACCAGGT1023GLYALAGLNGLYGLYLYSGLYASPALAGLYLYSPROGLYLEUPROGLY275280285TTGGCTGGATCTCCAGGAGTCAAAGGTGACCAAGGAAAACCTGGAGTG1071LEUALAGLYSERPROGLYVALLYSGLYASPGLNGLYLYSPROGLYVAL290295300CAGGGTGTTCCAGGCCCTCAAGGTGCACCAGGACTTTCAGGTGCCAAG1119GLNGLYVALPROGLYPROGLNGLYALAPROGLYLEUSERGLYALALYS305310315320GGTGAGCCAGGACGCACTGGTCTTCCTGGGCCAGCAGGACCCCCGGGA1167GLYGLUPROGLYARGTHRGLYLEUPROGLYPROALAGLYPROPROGLY325330335ATTGCTGGGAATCCAGGGATTGCAGGTGTGAAAGGAAGCAAGGGTGAC1215ILEALAGLYASNPROGLYILEALAGLYVALLYSGLYSERLYSGLYASP340345350ACAGGAATTCAAGGACAGAAAGGCACAAAAGGAGAATCAGGAGTCCCA1263THRGLYILEGLNGLYGLNLYSGLYTHRLYSGLYGLUSERGLYVALPRO355360365GGTCTTGTAGGCAGAAAGGGAGACACTGGAAGCCCTGGGCTGGCAGGT1311GLYLEUVALGLYARGLYSGLYASPTHRGLYSERPROGLYLEUALAGLY370375380CCCAAAGGAGAACCTGGACGAGTCGGTCAGAAGGGAGACCCGGGGATG1359PROLYSGLYGLUPROGLYARGVALGLYGLNLYSGLYASPPROGLYMET385390395400AAAGGGTCTTCTGGCCAGCAAGGACAAAAGGGAGAAAAGGGTCAAAAA1407LYSGLYSERSERGLYGLNGLNGLYGLNLYSGLYGLULYSGLYGLNLYS405410415GGCGAATCTTTCCAACGCGTCCGGATCATGGGTGGCACCAACAGAGGC1455GLYGLUSERPHEGLNARGVALARGILEMETGLYGLYTHRASNARGGLY420425430CGAGCTGAAGTTTACTATAACAATGAGTGGGGGACAATTTGTGATGAT1503ARGALAGLUVALTYRTYRASNASNGLUTRPGLYTHRILECYSASPASP435440445GATTGGGATAATAATGATGCGACTGTCTTCTGTCGCATGCTCGGTTAC1551ASPTRPASPASNASNASPALATHRVALPHECYSARGMETLEUGLYTYR450455460TCCAGAGGGAGAGCACTTAGCAGCTATGGAGGTGGCTCTGGGAACATC1599SERARGGLYARGALALEUSERSERTYRGLYGLYGLYSERGLYASNILE465470475480TGGCTGGACAATGTGAATTGTCGGGGCACAGAGAACAGTTTGTGGGAC1647TRPLEUASPASNVALASNCYSARGGLYTHRGLUASNSERLEUTRPASP485490495TGCAGTAAGAACTCCTGGGGCAATCACAATTGCGTACATAATGAAGAT1695CYSSERLYSASNSERTRPGLYASNHISASNCYSVALHISASNGLUASP500505510GCGGGTGTGGAATGCTCCTGACTTGGGAGCCCGAGAGGTCATCAGTGTGTCCCC1749ALAGLYVALGLUCYSSERter515AGGTGTCTTTGGTTCCACCCACATGGAAATCTGTGGGCTTGCCAACTCTGTTGAGGGGAA1809GTTAATAAAGCTCAAGTGGGGATCTGAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA1868(2) INFORMATION FOR SEQ ID NO:2:(i) SEQUENCE CHARACTERISTICS:(A) LENGTH: 518 amino acids(B) TYPE: amino acid(C) STRANDEDNESS: Single(D) TOPOLOGY: Linear(x) SEQUENCE DESCRIPTION: SEQ ID NO:2:MetGlySerLysGluLeuLeuLysGluGluAspPhe1510LeuGlySerThrGluAspArgAlaAspPheAspGln1520AlaMetPheProValMetGluThrPheGluIleAsn253035AspProValProLysLysArgAsnGlyGlyThrPhe4045CysMetAlaValMetAlaIleHisLeuIleLeuLeu505560ThrAlaGlyThrAlaLeuLeuLeuIleGlnValLeu6570AsnLeuGlnGluGlnLeuGlnMetLeuGluMetCys7580CysGlyAsnGlySerLeuAlaIleGluAspLysPro859095PhePheSerLeuGlnTrpAlaProLysThrHisLeu100105ValProArgAlaGlnGlyLeuGlnAlaLeuGlnAla110115120GlnLeuSerTrpValHisThrSerGlnGluGlnLeu125130ArgGlnGlnPheAsnAsnLeuThrGlnAsnProGlu135140LeuPheGlnIleLysGlyGluArgGlySerProGly145150155ProLysGlyAlaProGlyAlaProGlyIleProGly160165LeuProGlyProAlaAlaGluLysGlyGluLysGly170175180AlaAlaGlyArgAspGlyThrProGlyValGlnGly185190ProGlnGlyProProGlySerLysGlyGluAlaGly195200LeuGlnGlyLeuThrGlyAlaProGlyLysGlnGly205210215AlaThrGlyAlaProGlyProArgGlyGluLysGly220225SerLysGlyAspIleGlyLeuThrGlyProLysGly230235240GluHisGlyThrLysGlyAspLysGlyAspLeuGly245250LeuProGlyAsnLysGlyAspMetGlyMetLysGly255260AspThrGlyProMetGlySerProGlyAlaGlnGly265270275GlyLysGlyAspAlaGlyLysProGlyLeuProGly280285LeuAlaGlySerProGlyValLysGlyAspGlnGly290295300LysProGlyValGlnGlyValProGlyProGlnGly305310AlaProGlyLeuSerGlyAlaLysGlyGluProGly315320ArgThrGlyLeuProGlyProAlaGlyProProGly325330335IleAlaGlyAsnProGlyIleAlaGlyValLysGly340345SerLysGlyAspThrGlyIleGlnGlyGlnLysGly350355360ThrLysGlyGluSerGlyValProGlyLeuValGly365370ArgLysGlyAspThrGlySerProGlyLeuAlaGly375380ProLysGlyGluProGlyArgValGlyGlnLysGly385390395AspProGlyMetLysGlySerSerGlyGlnGlnGly400405GlnLysGlyGluLysGlyGlnLysGlyGluSerPhe410415420GlnArgValArgIleMetGlyGlyThrAsnArgGly425430ArgAlaGluValTyrTyrAsnAsnGluTrpGlyThr435440IleCysAspAspAspTrpAspAsnAsnAspAlaThr445450455ValPheCysArgMetLeuGlyTyrSerArgGlyArg460465AlaLeuSerSerTyrGlyGlyGlySerGlyAsnIle470475480TrpLeuAspAsnValAsnCysArgGlyThrGluAsn485490SerLeuTrpAspCysSerLysAsnSerTrpGlyAsn495500HisAsnCysValHisAsnGluAspAlaGlyValGlu505510515CysSer__________________________________________________________________________

The present invention is directed to processes for isolating and identifying the nucleotide sequence of a gene for a novel macrophage receptor with collagenous structure, termed "MARCO". The new macrophage receptor with a collagenous domain binds gram positive and negative bacteria and acetylated LDL. Moreover, the invention relates to the nucleotide sequence for MARCO identified by the process of the invention and the isolated and purified polypeptide chain encoded by such a sequence.

RELATED APPLICATION This application claims priority under 35 U.S.C. §119 or 365 to Great Britain, Application No. 0807506.1, filed Apr. 24, 2008. The entire teachings of the above application are incorporated herein by reference. TECHNICAL FIELD This invention relates to a communication method and apparatus, particularly but not exclusively for use in packet-based communication systems. BACKGROUND Packet-based communication systems allow the user of a device, such as a personal computer, to communicate across a computer network such as the Internet. Packet-based communication systems include voice over internet protocol (“VoIP”) communication systems. These systems are beneficial to the user as they are often of significantly lower cost than fixed line or mobile networks. This may particularly be the case for long-distance communication. To use a VoIP system, the user must install and execute client software on their device. The client software provides the VoIP connections as well as other functions such as registration and authentication. In addition to voice communication, the client may also provide further features such as video calling, instant messaging, voicemail and file transfer. SUMMARY One type of packet-based communication system uses a peer-to-peer (“P2P”) topology built on proprietary protocols. To enable access to a peer-to-peer system, the user must execute P2P client software provided by a P2P software provider on their computer, and register with the P2P system. When the user registers with the P2P system the client software is provided with a digital certificate from a server. Once the client software has been provided with the certificate, communication can subsequently be set up and routed between users of the P2P system without the further use of a server. In particular, the users can establish their own communication routes through the P2P system based on the exchange of one or more digital certificates (or user identity certificates, “UIC”), which enable access to the P2P system. The exchange of the digital certificates between users provides proof of the users' identities and that they are suitably authorised and authenticated in the P2P system. Therefore, the presentation of digital certificates provides trust in the identity of the user. It is therefore a characteristic of peer-to-peer communication that the communication is not routed using a server but directly from end-user to end-user. Further details on such a P2P system are disclosed in WO 2005/009019. The client software enables a large variety of different communication events (e.g. voice calls, instant messages, voicemails, video calls and file transfers) to be received at the user terminal of a user from a potentially large number of contacts. It can therefore be difficult for the user to keep track of the ongoing conversations and communication events that are received at the client. The invention seeks to provide a method of sorting communication events at a user terminal that enables the user to readily maintain and access ongoing communications. According to one aspect of the invention there is provided a method of sorting communication events at a user terminal connected to a communication network and executing a communication client arranged to be operable by a user, the method comprising: storing an event list comprising a list of identifiers, each identifier having information relating to at least one previously received communication event associated therewith, wherein the identifier identifies the initiator of the associated at least one previously received communication event and each identifier is listed only once in the list of identifiers; displaying the event list in a user interface of the communication client; receiving an incoming communication event at the user terminal from an initiating user over the communication network; determining whether the initiating user is present in the list of identifiers stored in the event list; in the case that the initiating user is present in the list of identifiers, amending the event list by adding information relating to the incoming communication event to the information relating to the at least one previously received communication event associated with the identifier of the initiating user; in the case that the initiating user is not present in the list of identifiers, creating a new entry at the top of the event list comprising an identifier for the initiating user and having information relating to the incoming communication event associated therewith; and updating the display of the event list in the user interface of the communication client. According to another aspect of the invention, there is provided a user terminal connected to a communication network and executing a communication client arranged to be operable by a user, comprising: a storage means arranged to store an event list comprising a list of identifiers, each identifier having information relating to at least one previously received communication event associated therewith, wherein the identifier identifies the initiator of the associated at least one previously received communication event and each identifier is listed only once in the list of identifiers; a receiving means arranged to receive an incoming communication event at the user terminal from an initiating user over the communication network; a processing means arranged to determine whether the initiating user is present in the list of identifiers stored in the event list, such that, in the case that the initiating user is present in the list of identifiers, the processing means is arranged to amend the event list by adding information relating to the incoming communication event to the information relating to the at least one previously received communication event associated with the identifier of the initiating user, and, in the case that the initiating user is not present in the list of identifiers, the processing means is arranged to create a new entry at the top of the event list comprising an identifier for the initiating user and having information relating to the incoming communication event associated therewith; and a display means arranged to display the event list in a user interface of the communication client. According to another aspect of the invention, there is provided a method of sorting communication events at a user terminal connected to a communication network and executing a communication client arranged to be operable by a user, the method comprising: storing an event list comprising a list of identifiers, each identifier having information relating to at least one previously received communication event and a priority weighting associated therewith, wherein the identifier identifies the initiator of the associated at least one previously received communication event, each identifier is listed only once in the list of identifiers, and the event list is ordered according to the priority weighting; displaying the event list in a user interface of the communication client; receiving an incoming communication event at the user terminal from an initiating user over the communication network; determining whether the initiating user is present in the list of identifiers stored in the event list; in the case that the initiating user is present in the list of identifiers, amending the event list by adding information relating to the incoming communication event to the information relating to the at least one previously received communication event associated with the identifier of the initiating user; in the case that the initiating user is not present in the list of identifiers, determining the priority weighting for the incoming communication event and creating a new entry at a position in the event list in dependence on the priority weighting, the new entry comprising an identifier for the initiating user and having information relating to the incoming communication event associated therewith; and updating the display of the event list in the user interface of the communication client. According to another aspect of the invention, there is provided a user terminal connected to a communication network and executing a communication client arranged to be operable by a user, comprising: a storage means arranged to store an event list comprising a list of identifiers, each identifier having information relating to at least one previously received communication event and a priority weighting associated therewith, wherein the identifier identifies the initiator of the associated at least one previously received communication event, each identifier is listed only once in the list of identifiers, and the event list is ordered according to the priority weighting; a receiving means arranged to receive an incoming communication event at the user terminal from an initiating user over the communication network; a processing means arranged to determine whether the initiating user is present in the list of identifiers stored in the event list, such that, in the case that the initiating user is present in the list of identifiers, the processing means is arranged to amend the event list by adding information relating to the incoming communication event to the information relating to the at least one previously received communication event associated with the identifier of the initiating user, and, in the case that the initiating user is not present in the list of identifiers, the processing means is arranged to determine the priority weighting for the incoming communication event and create a new entry at a position in the event list in dependence on the priority weighting, the new entry comprising an identifier for the initiating user and having information relating to the incoming communication event associated therewith; and a display means arranged to display the event list in a user interface of the communication client. According to another aspect of the invention, there is provided a computer program product comprising program code means which when executed by a computer implement the steps according to the above-described method. BRIEF DESCRIPTION OF THE DRAWINGS For a better understanding of the present invention and to show how the same may be put into effect, reference will now be made, by way of example, to the following drawings in which: FIG. 1 shows a packet-based communication system. FIG. 2 shows a user interface of a communication client. FIG. 3 shows a user terminal on which is executed a communication client. FIGS. 4A and 4B shows a contact list user interface of a communication client. FIGS. 5A and 5B shows a conversation list user interface of a communication client. FIG. 6 shows a flowchart of a method of sorting the entries in the conversation list. FIG. 7A-7C shows the behaviour of the conversation list with new communication events in a first scenario. FIG. 8A-8C shows the behaviour of the conversation list with new communication events in a second scenario. FIG. 9 shows the conversation list user interface with an incoming call. FIG. 10 shows the conversation list user interface with a plurality of entries arriving over a period of time. FIG. 11 shows marking an entry in the conversation list as unread. FIG. 12 shows a flowchart of an alternative method of sorting the entries in the conversation list. DETAILED DESCRIPTION Reference is first made to FIG. 1 , which illustrates a P2P communication system 100 . Note that whilst this illustrative embodiment is described with reference to a P2P communication system, other types of communication system could also be used, such as non-P2P, VoIP systems. A first user of the P2P communication system (named “Tom Smith” 102 ) operates a user terminal 104 , which is shown connected to a P2P network 106 . Note that the P2P network 106 utilises a communication system such as the Internet. The user terminal 104 may be, for example, a personal computer (“PC”), personal digital assistant (“PDA”), a mobile phone, a gaming device or other embedded device able to connect to the P2P network 106 . The user device is arranged to receive information from and output information to a user of the device. In a preferred embodiment of the invention the user device comprises a display such as a screen and a keyboard and mouse. The user device 104 is connected to the P2P network 106 via a network interface 108 such as a modem, and the connection between the user terminal 104 and the network interface 108 may be via a cable (wired) connection or a wireless connection. The user terminal 104 is running a client 110 , provided by the P2P software provider. The client 110 is a software program executed on a local processor in the user terminal 104 . The user terminal 104 is also connected to a handset 112 , which comprises a speaker and microphone to enable the user to listen and speak in a voice call. The microphone and speaker does not necessarily have to be in the form of a traditional telephone handset, but can be in the form of a headphone or earphone with an integrated microphone, or as a separate loudspeaker and microphone independently connected to the user terminal 104 . An example of a user interface 200 of the client 110 executed on the user terminal 104 of the first user “Tom Smith” 102 is shown illustrated in FIG. 2 . The client user interface 200 displays the username 202 of “Tom Smith” 102 in the P2P system, and the user can set his own presence state (that will be seen by other users) using a drop down list by selecting icon 204 . The client user interface 200 comprises a button 206 labelled “contacts”, and when this button is selected the contacts stored by the user in a contact list are displayed in a pane 209 below the button 206 . In the example user interface in FIG. 2 , four contacts of other users of the P2P system are shown listed in contact list 208 . Each of these contacts have authorised the user of the client 110 to view their contact details and presence state and mood message information. Each contact in the contact list has a presence status icon associated with it. For example, the presence status icon for “Kevin Jackson” 210 indicates that this contact is “online”, the presence icon for “Maria Jones” 212 indicates that this contact is “not available”, the presence icon for “Roger White” 214 indicates that this contact's state is “do not disturb”, the presence icon for “Sarah Rowling” 216 indicates that this contact is “offline”. Further presence indications can also be included. Next to the names of the contacts in pane 209 are mood messages 220 of the contacts. The contact list for the users (e.g. the contact list 208 for “Tom Smith”) is stored in a contact server (not shown in FIG. 1 ). When the client 110 first logs into the P2P system the contact server is contacted, and the contact list is downloaded to the user terminal 104 . This allows the user to log into the P2P system from any terminal and still access the same contact list. The contact server is also used to store the user's own mood message (e.g. a mood message 222 of the first user 102 ) and a picture 224 selected to represent the user (known as an avatar). This information can be downloaded to the client 110 , and allows this information to be consistent for the user when logging on from different terminals. The client 110 also periodically communicates with the contact server in order to obtain any changes to the information on the contacts in the contact list, or to update the stored contact list with any new contacts that have been added. Presence state information is not stored centrally in the contact server. Rather, the client 110 periodically requests the presence state information for each of the contacts in the contact list 208 directly over the P2P system. Similarly, the current mood message for each of the contacts, as well as a picture (avatar—e.g. picture 226 for “Kevin Jackson”) that has been chosen to represent the contact, are also retrieved by the client 110 directly from the respective clients of each of the contacts over the P2P system. Calls to the P2P users in the contact list may be initiated over the P2P system by selecting the contact and clicking on a “call” button 228 using a pointing device such as a mouse. Referring again to FIG. 1 , the call set-up is performed using proprietary protocols, and the route over the network 106 between the calling user and called user is determined by the peer-to-peer system without the use of servers. For example, the first user 102 can call a second user “Kevin Jackson” 114 . Following authentication through the presentation of digital certificates (to prove that the users are genuine subscribers of the P2P system—described in more detail in WO 2005/009019), the call can be made using VoIP. The client 110 performs the encoding and decoding of VoIP packets. VoIP packets from the user terminal 104 are transmitted into the network 106 via the network interface 108 , and routed to a computer terminal 116 of the called party 114 , via a network interface 118 . A client 120 (similar to the client 110 ) running on the user terminal 116 of the called user 114 decodes the VoIP packets to produce an audio signal that can be heard by the called user using the handset 122 . Conversely, when the second user 114 talks into handset 122 , the client 120 executed on user terminal 116 encodes the audio signals into VoIP packets and transmits them across the network 106 to the user terminal 104 . The client 110 executed on user terminal 104 decodes the VoIP packets, and produces an audio signal that can be heard by the user of the handset 112 . The VoIP packets for calls between P2P users (such as 102 and 114 ) as described above are passed across the network 106 only, and the PSTN network is not involved. Furthermore, due to the P2P nature of the system, the actual voice calls between users of the P2P system can be made with no central servers being used. This has the advantages that the network scales easily and maintains a high voice quality, and the call can be made free to the users. Additionally, calls can also be made from the client ( 110 , 122 ) using the P2P system to fixed-line or mobile telephones, by routing the call to the PSTN network. Similarly, calls from fixed-line or mobile telephones can be made to the P2P system via the PSTN. In addition to making voice calls, the user of the client 110 can also communicate with the users listed in the contact list 208 in several other ways. For example, an instant message (also known as a chat message) can be sent by typing a message in box 230 and sending it by selecting the “send message” button 232 . Additionally, the first user 102 can use the client 110 to transmit files to users in the contact list 208 , send voicemails to the contacts or establish video calls with the contacts (not illustrated in FIG. 2 ). FIG. 3 illustrates a detailed view of the user terminal ( 104 ) on which is executed client 110 . The user terminal 104 comprises a central processing unit (“CPU”) 302 , to which is connected a display 304 such as a screen, an input device such as a keyboard 306 , a pointing device such as a mouse 308 , a speaker 310 and a microphone 312 . The speaker 310 and microphone 312 may be integrated into a handset 112 or headset, or may be separate. The CPU 302 is connected to a network interface 108 as shown in FIG. 1 . FIG. 3 also illustrates an operating system (“OS”) 314 executed on the CPU 302 . Running on top of the OS 314 is a software stack 316 for the client 110 . The software stack shows a protocol layer 318 , a client engine layer 320 and a client user interface layer (“UI”) 322 . Each layer is responsible for specific functions. Because each layer usually communicates with two other layers, they are regarded as being arranged in a stack as shown in FIG. 3 . The operating system 314 manages the hardware resources of the computer and handles data being transmitted to and from the network via the network interface 108 . The client protocol layer 318 of the client software communicates with the operating system 314 and manages the connections over the P2P system. Processes requiring higher level processing are passed to the client engine layer 320 . The client engine 320 also communicates with the client user interface layer 322 . The client engine 320 may be arranged to control the client user interface layer 322 to present information to the user via the user interface of the client (as shown in FIG. 2 ) and to receive information from the user via the user interface. Furthermore, the client engine layer 320 is also arranged to store information relating to communication events received at the client in a storage device 321 . For example, the client engine 320 stores messages (e.g. IM chat messages) as well as information about communication events, such as their sender and the time they are received. The client engine layer 320 is arranged to control the display of information regarding these communication events to the user on the display 304 , and also perform calculations on the information contained therein, as described hereinafter. A communication client may therefore be capable of receiving a variety of different types of communication event. Furthermore, these communication events can often be received contemporaneously, such that, for example, voice calls, IM messages and file transfers are all received in close succession. It can therefore become difficult for the user to manage all the communication events that are happening in the client. This is compounded if the user has a large number of contacts. This is particularly the case when the client is arranged to open a new user interface window for each communication event that is incoming to the client. This can often result in the user having many windows open on his user terminal, each of which can have different communications ongoing with different contacts. This can cause a great deal of confusion to the user, as it becomes hard to manage all the open windows. Frequently, this leads the user to close some of the windows, with the result that the user neglects certain ongoing communications by, for example, forgetting to reply to a message. It is therefore advantageous to have a technique of organising and sorting all the communication events at the client, such the communication events can be much more easily and effectively managed by the user. Such a technique is presented herein. To describe the operation of the method of sorting and arranging the communication events, reference is first made to FIG. 4A . FIG. 4A illustrates the pane 209 of the client user interface, as shown in FIG. 2 , prior to a communication event being received at the user terminal 104 . The button labelled “Contacts” 206 has been selected such that the full contact list 208 of the user is displayed. FIG. 4B illustrates the pane 209 of the client user interface following a communication event being received at the user terminal 104 . In this example, a communication event is received from the user “Maria Jones”. This is, for example, an IM chat message, although other types of communication event could also be received. The receipt of the communication event is processed by the client engine 320 and stored in the communication event storage device 321 . The receipt of a communication event is indicated with a marker 402 next to the contact's name in the contact list 208 . In addition, a button labelled “Conversations” 234 is highlighted, preferably by changing the button's colour (not illustrated in FIG. 4B ) and by the addition of a numeric indicator 404 to indicate to the user the number of new communication events that have been received. The “Conversations” button 234 enables the user to view currently active communication events, thereby enabling the user to quickly and efficiently see what communication is ongoing in the client. The operation of the “Conversations” button 234 is described hereinafter. FIG. 5A illustrates the effect of the user selecting the “Conversations” button 234 . When the “Conversations” button 234 is selected, the contact list 208 is removed from the pane 209 , and replaced by a list of conversations 502 that the user is or has been engaged in using the client 110 . A “conversation” in this context corresponds to an aggregation of the communication events that the user has had (or is having) with a particular contact. For example, the “conversation” stream between the user “Tom Smith” and “Kevin Jackson” (as illustrated in FIG. 1 ) can comprise a plurality of IM chats, voice calls, file transfers and voicemails sent and received over a period of time. Therefore, a “conversation” for a certain contact is a grouping of all the different types of communication event that has occurred with that contact, sorted by the name of the contact. Information on the conversation stream with a particular contact is accessible to the user by selecting the contact's name in the conversation list 502 . Therefore, a conversation list is a list of ongoing communications, organised by the names of the contacts with which communications is ongoing. In particular, the name of a contact appears only once in the contact list, and information regarding all the ongoing communications (potentially of different types) with this contact is accessible by the user selecting the name of the contact. An entry for a particular contact is included in the conversation list after receipt of a communication event from the contact, and this entry remains in the conversation list until it is manually cleared by the user. In the case of the example shown in FIG. 5A , a single communication event has occurred, which is an IM chat received from “Maria Jones”. The numeric indicator 402 on the “Conversations” button 234 indicates that there is one unacknowledged (unread) conversation. The conversation list 502 displays the name 504 of the contact from which the communication event was received and a summary 506 of the communication (e.g. the first line of the IM chat in this example). A further numerical indicator 508 shows the number of unacknowledged communication events that have been received from this particular contact. A date indicator 510 indicates the date on which the communication event present in the conversation list 502 was received. In the specific case of IM chat messages, the further numeric indicator 508 counts the number of individual unread chat messages that are received from a particular contact in a single session. Therefore, the number in the further numerical indicator 508 can be higher than the number shown in the indicator 402 on the “Conversations” button 234 . This is because the number shown in the indicator 402 on the “Conversations” button 234 indicates the total number of unacknowledged conversations, whereas the further numerical indicator 508 indicates the number of unread messages. In other words, the example in FIG. 5A indicates that there is one unread conversation, and this conversation comprises three unread IM chat messages. Note that the number shown on the numeric indicator 508 does not only refer to IM chat messages, but represents an aggregate of all other unacknowledged communication events, including further events such as file transfers, voicemails, missed calls and other events. Therefore, when new communication events are received at the client, they are stored in the communication event storage 321 (along with their date and time of arrival) and displayed in the conversation list 502 according to the contact to which they relate. Hence, the information is arranged according to the contact from which the communication event was received, regardless of the type of communication or whether there is a combination thereof. FIG. 5B illustrates the conversation list 502 after the user 102 has selected the entry from “Maria Jones”. When a conversation listed under a contact's name in the conversation list 502 is selected, the information related to the communication event is displayed to the user. For example, in the case of the IM chat in FIG. 5B , the three IM chat messages sent from “Maria Jones” are displayed in another portion of the client user interface (not shown in FIG. 5B ). Because these messages are now considered to have been read or acknowledged by the user, the look of the entry in the conversation list is changed, preferably so that the summary ( 506 in FIG. 5A ) is removed. The user can now tell that this entry relates to a conversation that has been read. When an entry in the conversation list 502 has been selected by the user 102 , the further numerical indicator 508 is replaced by a “close” button 512 . The “close” button 502 removes the entry for this contact from the conversation list 502 . This allows the user 102 to manually control which conversations remain in the conversation list (e.g. if they require further action, replies, etc.) and which ones can be removed (e.g. if they have been acknowledged or can be ignored). It should be noted that if an entry is removed from the conversation list 502 using the close button 512 , then the contact is not removed from contact list 208 , and the information regarding the communication event or contained therein may further remain accessible to the user via an additional stored communication history record. Obviously, unless the user is proactively removing entries from the conversation list 502 as soon as they are read, then it will quickly become populated with a large number of contacts from whom communication events have been received, such that it becomes unwieldy for the user to distinguish which communication events are new and need acting upon, and which are old or can be ignored. This therefore becomes similar to a simple history of all communication events received at the client. This has the same problem as the contact list, in that it is difficult to manage the active conversations. A technique for managing the entries in the conversation list 502 to solve this problem is described with reference to FIG. 6 . FIG. 6 illustrates a flowchart for determining how to sort the entries in the conversations list 502 . Specifically, the flowchart in FIG. 6 determines where in the conversation list 502 an entry should be placed when a communication event arrives at the client 110 . In step S 602 a communication event is received at the client 110 from a contact of the user 102 . In step S 604 , it is checked whether the incoming communication event relates to a previous entry already present in the conversation list 502 . Preferably, this step checks whether an entry is already present in the conversation list 502 from the same contact as the newly received communication event. If this is not the case, then the incoming communication event requires a new entry in the conversations list 502 . As this is a new entry in the list, it needs to be made prominent to the user. Entries that are at the top of the conversations list are the most prominent to the users, and hence the most likely to be seen and acted upon. Therefore, in step S 606 , the new entry is placed at the top of the conversation list 502 . If the incoming communication event does relate to a previously received communication event that is still listed in the conversation list 502 (e.g. if a new communication event is received from a contact already listed in the conversation list, regardless of whether it is the same type of communication event), then a decision has to be made as to whether to maintain the current entry in its existing position in the list, but update it to indicate a new communication event has been received (i.e. increment the numerical indicator 508 and show the summary 506 shown in FIG. 5A ), or to move the entry for this contact in the conversation list 502 to the top of the list (and also increment the numerical indicator 508 and show the summary 506 shown in FIG. 5A ). It is important to appreciate that there is never more than one entry in the conversation list for a particular contact. Therefore, the choice is only whether to move the existing entry in the conversation list or to keep it in its existing position. However, there is a trade-off to be made between moving the entries and maintaining them. Moving an entry to the top of the list makes it more prominent to the user. However, excessive rearrangement of the entries in the conversation list makes it difficult for the user to keep track of where entries are, and hence it becomes more difficult for the user to find a given entry again. In preferred embodiments, to avoid excessive rearrangement of conversation list entries, and the consequential confusion caused to the user, the entry for a particular contact is only moved in the conversation list 502 if a predetermined period of time has elapsed since the previous most recent communication event for that contact was received. In step S 608 , the time of arrival of the new communication event is compared to the time of the previous communication event for this contact. In the case that the time difference between the current and previous communication event for this contact is less than the predetermined period, then, in step S 610 , the position of the contact in the conversation list 502 is maintained (i.e. not moved), but is updated to reflect the new communication event (i.e. incrementing the numerical indicator 508 and adding the summary 506 as shown in FIG. 5A ). This ensures that when several communication events are arriving from a particular contact in reasonably close succession, the entry in the conversation list 502 is not constantly moving to the top of the list. This is particularly useful in the case that there are further concurrent communication events arriving from other contacts, as this would otherwise result in the entry at the top of the conversation list 502 swapping frequently between the active contacts as the communication events arrived. In the case that the time difference between the current and previous communication event for this contact is greater than the predetermined period, then, in step S 612 , the position of the contact in the conversation list 502 is moved to the top of the conversation list 502 . The entry is also updated to reflect the new communication event (i.e. incrementing the numerical indicator 508 and adding the summary 506 as shown in FIG. 5A ). Preferably, the predetermined time period above which the entry in the conversation list is moved to the top is one hour. However, the value used can be configurable to any value depending on user behaviour and the types of communication events that can be received at the client 110 . The operation of the flowchart in FIG. 6 is further illustrated with reference to FIGS. 7A-C and 8 A-C. Reference is first made to FIG. 7A , which illustrates the conversation list 502 shown in the pane 209 in the state as shown in FIG. 5B , such that a communication event (in this case in IM chat message) has been received from “Maria Jones” and read by the user. In addition, a further new communication event has been received from a different contact, “Roger White”. Because there is not a previous entry in the conversation list 502 for “Roger White”, then the result of the analysis in step S 604 is negative and the entry 702 is displayed at the top of the conversation list 502 (step S 606 ), as illustrated in FIG. 7A . The entry 702 for “Roger White” also has a summary 704 and a numerical indicator 706 showing the number of unacknowledged communication events, in order to indicate to the user that there are unread/unacknowledged communication events from this contact. In FIG. 7B , time has passed since the communication event from “Roger White” arrived. Specifically, the user has viewed the message from “Roger White” by selecting the entry 702 in the conversation list 502 , such that only his name is now displayed (i.e. the summary 704 and indicator 706 are removed), and sufficient time has elapsed such that the communication events from “Roger White” and “Maria Jones” are shown as having been received yesterday by date indicator 510 . In particular, the time elapsed since the last communication event from “Maria Jones” is greater than the predetermined time in step S 608 . FIG. 7C shows the situation where, following the elapsed time, an additional communication event has been received from “Maria Jones”. Because there is already an entry 504 in the conversation list 502 for “Maria Jones”, the result of the analysis in step S 604 is positive, and the time difference between the new and previous communication event of “Maria Jones” is considered in step S 608 . As stated above, this is greater than the predetermined time period. Therefore, according to step S 612 , the entry 504 for “Maria Jones” is moved to the top of the conversation list 502 , as illustrated in FIG. 7C . The presence of an unread communication event is indicated to the user by the addition of summary line 708 and a numerical indicator 710 to show the number of unacknowledged communication events from this contact. Indicator 402 is also incremented. The date indicator 510 now shows that the communication event from “Maria Jones” was received today. An additional date indicator 712 is therefore required for yesterday, under which the entry for “Roger White” remains. An alternative scenario is illustrated with reference to FIGS. 8A-8C . FIG. 8A shows an identical scenario to FIG. 7A , in that a communication event has been received from “Roger White” which is placed at the top of the conversation list 502 . FIG. 8B shows a similar scenario to FIG. 7B described above, except that a shorter period of time has elapsed. In particular, the time that has elapsed since the arrival of the communication event for “Maria Jones” at entry 504 in the conversation list 502 is less than the predetermined time period of S 608 . Note that (in comparison to FIG. 7B ) the date indicator 510 still reads “today”. FIG. 8C shows the situation where, following the elapsed time, an additional communication event has been received from “Maria Jones”. Because there is already an entry 504 in the conversation list 502 for “Maria Jones”, the result of the analysis in step S 604 is positive. The time difference between the new and previous communication event of “Maria Jones” is considered in step S 608 , which is, as stated above, less than the predetermined time period. Therefore, according to step S 610 , the entry 504 for “Maria Jones” is maintained in its current position (and not moved to the top of the conversation list 502 ) as illustrated in FIG. 8C . The presence of an unread communication event is indicated to the user by the addition of summary line 802 and a numerical indicator 804 to show the number of unacknowledged communication events from this contact. Indicator 402 is also incremented. Therefore, FIGS. 7A-7C illustrate the case where a communication event is received, and the time elapsed since the previous communication event from that contact was received is greater than a predetermined period, and FIGS. 8A-8C illustrate the case where the time period is less than a predetermined period. This technique ensures that entries in the conversation list are not moved around unnecessarily, thereby increasing the usability of the conversation list. Reference is now made to FIG. 9 , which illustrates a further enhancement to the operation of the conversation list sorting technique shown in FIG. 6 . Certain communication events have the specific property that they need to be acted on immediately. An example of this is a voice call. If a voice call is received at the client, the user needs to answer it within a short period of time, as otherwise the calling user will hang-up or be diverted to the called user's voicemail. Other examples of this type of communication event are a video call or a voicemail. It is therefore desirable to ensure that these communication events are brought to the user's attention immediately, regardless of how recently a previous communication event from this contact was received. As a result of this, the flowchart of FIG. 6 can be modified to assess the type of communication event, such that if the communication event is an incoming call (voice or video) or voicemail then an entry in the conversation list is always placed at the top of the list. This is illustrated in FIG. 9 , where a notification of an incoming call from “Sarah Rowling” is displayed at the top of the conversation list 502 with an appropriate icon 904 . Furthermore, if an incoming call is unanswered, then an entry is placed in the conversation list 502 to notify the user of a missed call. Preferably, this type of event is also always placed at the top of the conversation list in order to increase its prominence to the user. However, in alternative embodiments, the time difference elapsed since the last communication event with this contact can be taken into account. FIG. 10 illustrates a conversation list 502 comprising several communication events from different contacts that have occurred over a period of time. In particular, FIG. 10 shows a set of 17 unread IM chat messages from “Maria Jones” ( 1002 ); a file transfer from “Roger White” ( 1004 ); a missed call from “Sarah Rowling” ( 1006 ); and a communication event from “Kevin Jackson” ( 1008 ) that has been selected and read by the user. FIG. 10 further illustrates how the entries in the conversation list 502 are divided up into a plurality of time categories ( 1010 , 1012 , 1014 ), such that a degree of chronology for the arrival of the communication events can be discerned by the user. Note however, that whilst these time categories do indicate the date on which a communication event was received, the individual entries within a single date are not necessarily in a precise chronological order, as they may or may not be moved within the conversation list depending on the time interval between subsequent communication events from a given contact (as described with reference to FIG. 6 ). Therefore, the conversation list 502 does not represent merely a chronological history of communication events. FIG. 10 illustrates a selection of the types of communication event that can be shown in the conversation list. In particular, the conversation list 502 can include entries relating to the following communication events received at the client: Missed calls; New voicemails; IM chat message received; Incoming file transfer; Incoming authorisation request (i.e. from a person not yet in the user's contact list); Authorisation request accepted (i.e. a person has accepted a request for authorisation originating from the user of the client); Third party alerts (e.g. alerts from a payment provider); and Contact alerts (e.g. it is a contact's birthday). FIG. 11 illustrates a further feature of the conversation list 502 . Once the user has selected an entry in the conversation list 502 , the entry is shown as read/acknowledged. However, after initially viewing the entry in the conversation list, the user may wish to act further on this communication event (e.g. by sending an IM message reply, or returning a voice call). In order to highlight the fact that the communication event requires further action, the user can select the entry in the conversation list such that a menu of options 1102 is displayed. One of these options is “Mark as unread” 1104 . When this option is selected, an indictor 1106 is placed next to the entry in the conversation list 502 in order to highlight it to the user. The indicator is similar to the numerical indicators displayed for new communication events (such as indicator 508 of FIG. 5A ). Marking a conversation as unread shows the number of communication events that were present before the entry was selected (i.e. marked as read). This means that if an entry in the conversation list had five unread communication events before being selected, then selecting the entry clears the numerical indicator 508 showing “5”, and subsequently marking the entry as “unread” (with option 1104 ) restores the numerical indicator 508 showing “5”. This therefore enables the user to rapidly see entries in the conversation list that are marked as requiring further attention (i.e. are unacknowledged), thereby ensuring that important communication events are not forgotten about or ignored. In a further embodiment of the invention, the ordering of the entries in the conversation list can be based upon a weighting value assigned to each entry, such that the weighting value denotes a level of importance or priority to the entry. For example, communication events received from certain people can be more important to the user than others. It is therefore useful for the user to be able to assign importance or priority weightings to particular contacts in the contact list 208 . Such importance or priority weightings can take the form of simple “low”, “medium” or “high” weightings, or can be more precise, in the form of a one to ten rating. These weightings are set by the user and stored at the user terminal. Each contact will also have a default weighting, in case the user does not explicitly set a weighting. This can be, for example, a weighting of “medium” importance. Once the weightings are defined for the contacts, the ordering of the conversations list is performed according to the flowchart shown in FIG. 12 . In S 1202 an incoming communication event is received at the user terminal. In S 1204 it is determined whether the incoming communication event relates to a previous entry already present in the conversation list 502 . Preferably, this step checks whether an entry is already present in the conversation list 502 from the same contact as the newly received communication event. If the communication event does not relate to a previous entry in the conversation list, then in step S 1206 a weighting of the importance of the communication event is determined. This is performed by looking up the weighting value for the identity of the contact associated with of the communication event. In step S 1208 a new entry is created in the conversation list. However, unlike in FIG. 6 , in step S 1208 this is not always placed at the top of the list. Rather it is placed according to the weighting value, such that it is below entries with a higher importance weighting, but above those with a lower importance weighting. Therefore, the highest priority events are at the top of the conversation list, and the lowest priority events are at the bottom of the conversation list. In this way, new events from contacts that are deemed less important are not made as prominent to the user, whereas ones that are deemed very important are made most prominent as they will be placed at the top of the conversation list. Note that there can be situations where several events are in the list with the same weighting value (particularly if simple “low”, “medium” and “high” categories are used). In this case, the newest entries are preferably placed at the top of the older entries having a given priority weighting. However, in alternative embodiments, other contention mechanisms can be used, such as placing the entries in alphabetical order. Returning again to step S 1204 , if the communication event does relate to a previous entry in the conversation list, then in step S 1210 it is checked whether the weighting value for this contact remains consistent with the current position of the event in the conversation list. This can occur because the user can change the importance weighting for a given contact between receiving communication events. For example, if the user is expecting to receive an important communication event from a particular contact, then he can increase the importance weighting to “high” in order to ensure that he does not overlook the communication event. If the weighting value remains the same for the communication event then, in step S 1212 , the position of the entry in the conversation list is maintained, but updated to reflect the new communication event (as was shown with reference to FIG. 8C ). If the weighting value has changed, then in step S 1214 , the position of the entry in the conversation list is updated to reflect the changed weighting in a similar manner to the positioning of the new event in S 1208 . Specifically, the event is moved such that it is below entries with a higher importance weighting, but above those with a lower importance weighting. As described above, a contention mechanism is used when there are multiple entries with the same weighting value, such as placing the most recently received events above older events with the same weighting. The flowchart in FIG. 12 therefore provides a technique by which a conversation list can be ordered such that communication events deemed to have a higher importance than others are made more prominent to the user. In yet further embodiments, different measures of the weighting value can be used in combination with the flowchart of FIG. 12 . For example, rather than associating a weighing of importance to the identity of a contact, difference weightings can be associated to different types of communication event. For example, communications events such as missed voice or video calls can be given “high” priority, instant messaging can be given “medium” priority, and other events such as file transfers can be given “low” priority. The operation of the flowchart of FIG. 12 is then identical, but the ordering of the conversation list now depends on the type of communication event received. For example, following the receipt of IM messages from a contact, then there is an entry in the conversation list for this contact. After a period of time and the receipt of other messages from other users, this entry is located in the middle of the conversation list. However, if there is a missed call from this contact, then this has a higher priority weighting than IM messages, and the entry is moved to the top of the list. Furthermore, the importance weighting for a communication event can also be dependent on the contents of the communication event itself. For example, the user can define certain words as being a trigger for important messages. Therefore, the user defines a list of words and associates a particular priority weighting with each of these words. The contents of a message are compared to the trigger words, and any messages containing these words are given the associated weighting. This can be of particular use with regards to setting the weighting of IM messages, where the contents of the messages are simple text. However, it can also be used for file transfers, by utilising the contents of the file or the filename, or for voicemails by utilising speech recognition technology. This can also be used in combination with any of the previous techniques for ordering the conversation list, to give an additional level of accuracy to the ordering of the entries in the conversation list. While this invention has been particularly shown and described with reference to preferred embodiments, it will be understood to those skilled in the art that various changes in form and detail may be made without departing from the scope of the invention as defined by the appendant claims.

A method of sorting communication events at a user terminal connected to a communication network and executing a communication client arranged to be operable by a user is provided. The method comprises storing an event list comprising a list of identifiers, each identifier having information relating to at least one previously received communication event associated therewith, wherein the identifier identifies the initiator of the associated at least one previously received communication event and each identifier is listed only once in the list of identifiers. The event list is displayed in a user interface of the communication client. The method further comprises receiving an incoming communication event at the user terminal from an initiating user over the communication network and determining whether the initiating user is present in the list of identifiers stored in the event list. In the case that the initiating user is present in the list of identifiers, the event list is amended by adding information relating to the incoming communication event to the information relating to the at least one previously received communication event associated with the identifier of the initiating user. In the case that the initiating user is not present in the list of identifiers, a new entry is created at the top of the event list comprising an identifier for the initiating user and having information relating to the incoming communication event associated therewith. The display of the event list is updated in the user interface of the communication client.

This application is a US National Stage of International Application No. PCT/CN2012/085598, filed on 30 Nov. 2012, designating the United States, and claiming the benefit of Chinese Patent Application No. 201210484945.6, filed with the State Intellectual Property Office of People's Republic of China on Nov. 23, 2012 and entitled “Method and node device for transmitting data based on a Time Triggered Ethernet”, which is hereby incorporated by reference in its entirety. FIELD The present invention relates to the field of Ethernet technologies and particularly to a method and node device for transmitting data based on a Time Triggered Ethernet (TTE). BACKGROUND In recent years, the Ethernet has been significantly developed in the field of industry control into a widely applied local area network technology, and an industry control network can intercommunicate with the global Internet conveniently by using the Ethernet. Moreover a large number of upper protocols have been applied successfully to the Ethernet technology, for example, the TCP/IP protocol has been applied successfully to the Ethernet technology, so the Ethernet can be applied conveniently in various applications. A bus access scheme in the Time Triggered Architecture (TTA) is embodied as a Time Division Multiple Access (TDMA) scheme, where there are several timeslots included in one TDMA cycle. At most one of the timeslots in each cycle can be occupied by one switch, and the respective switches may transmit different data in each cycle. With the Time Triggered Ethernet (TTE), a time trigger is made instead of an event trigger so that a communication task is transmitted based on a timing trigger by reasonable schedule to be temporally triggered for transmission to thereby ensure contention for a physical link in data transmission so as to guarantee real-time data transmission. The TTE in the prior art can address the problem of contention for a physical link between devices to thereby guarantee real-time data transmission. Due to the TTE technology, although the problem of contention for a physical link between devices throughout the network can be solved, a considerable waste of bandwidth resources in the network may come therewith. The following description will be given with reference to the drawings. FIG. 1 illustrates a schematic diagram of data transmission based on the TTE in the prior art. The network includes a plurality of Personal Computers (PCs) (nodes) including P 1 to P 4 respectively, and a plurality of switches including a switch 1 , a switch 2 , a switch 3 and a switch 4 respectively. Here data need to be transmitted in real time between the PC 1 and the PC 2 , data need to be transmitted in real time between the PC 2 and the PC 3 , and data need to be transmitted in real time between the PC 3 and the PC 4 . In each scheduling cycle, a primary node allocates a timeslot to each of nodes so that in the timeslot allocated to the node, the entire physical link in a local area network, where the node is located, is for exclusive use by the node. For example, data need to be transmitted in real time between the PC 1 and the PC 2 , between the PC 2 and the PC 3 , and between the PC 3 and the PC 4 through the switch 1 to the switch 2 , the switch 2 to the switch 3 , and the switch 3 to the switch 4 respectively. The primary node allocates timeslots to the PC 1 , the PC 2 and the PC 3 respectively in a temporally sequential order in each scheduling cycle. The PC 1 transmits data through the physical link of the switch 1 to the switch 2 in the timeslot allocated thereto. In the TTE mechanism, the same primary node can schedule only one node in one timeslot even if the physical links where the other nodes are currently located are not occupied. As no timeslots have been currently allocated to the other nodes, their physical links have to be idle. For example at this time the PC 1 occupies the physical link of the switch 1 to the switch 2 , and the entire physical link of the switch 1 to the switch 2 to the switch 3 to the switch 4 in the local area network where the PC 1 is located is occupied by the PC 1 , so at this time even if the switch 2 to the switch 3 , and the switch 3 to the switch 4 are idle, they may not be available to the other nodes, thus resulting in a considerable waste of network bandwidths, and the waste of network bandwidths will be exacerbated if there are a larger number of nodes in the physical link of the local area network. SUMMARY Embodiments of the invention provide a method and node device for transmitting data based on a time triggered Ethernet (TTE) so as to address the problem of a waste of network bandwidths in data transmission based on the TTE in the prior art. The present invention provides a method for transmitting data based on a time triggered Ethernet (TTE), the method including: receiving, by each node, a scheduling period table, determined from time-triggered messages, transmitted by a primary node; determining, by a node, when the node has an event-triggered message to be transmitted, a physical link corresponding to the event-triggered message; judging, according to the physical link, timeslot allocation information and information about physical link corresponding to each timeslot, stored in the scheduling period table, whether the physical link collides with a physical link corresponding to a current timeslot; and transmitting the event-triggered message in the current timeslot when it is determined that there is no collision. The invention provides a device for transmitting data over a time triggered Ethernet, the device including: a receiving module configured to receive a scheduling period table, determined from time-triggered messages, transmitted by a primary node; a determining module configured, when there is an event-triggered message to be transmitted, to determine a physical link corresponding to the event-triggered message; a judging module configured to judge, according to the physical link, timeslot allocation information and information about physical link corresponding to each timeslot, stored in the scheduling period table, whether the physical link collides with a physical link corresponding to a current timeslot; and a transmitting module configured to transmit the event-triggered message in the current timeslot when the judging module determines that there is no collision. The embodiments of the present invention provide a method and node device for transmitting data based on a TTE, and in the method, the primary node determines a scheduling period table from time-triggered messages, and when each node has an event-triggered message to be transmitted, the node transmits the event-triggered message in the current timeslot upon determining from the information stored in the scheduling period table that a physical link occupied by the event-triggered message does not collide with a physical link corresponding to the current timeslot. In the present invention, the primary node will not allocate timeslots separately for the event-triggered messages of the respective nodes, and when each node has the event-triggered message to be transmitted, the node can transmit the event-triggered message in the current timeslot as long as the physical link occupied by the event-triggered message does not collide with the physical link corresponding to the current timeslot to thereby effectively improve the efficiency of data transmission and the utilization ratio of network bandwidths. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 illustrates a schematic diagram of data transmission based on the TTE in the prior art; FIG. 2 illustrates a schematic diagram of the process of data transmission based on the TTE according to a particular embodiment of the invention; FIG. 3 illustrates a schematic structural diagram of a scheduling period table generated by the primary node according to an embodiment of the invention; FIG. 4 illustrates a particular implementation of a method for transmitting data based on the TTE according to an embodiment of the invention; FIG. 5 illustrates another particular implementation of a method for transmitting data based on the TTE according to an embodiment of the invention; and FIG. 6 illustrates a schematic structural diagram of a device node for transmitting data based on the Time-Triggered Ethernet (TTE) according to an embodiment of the invention. DETAILED DESCRIPTION OF THE EMBODIMENTS The invention provides a method and node device for transmitting data based on a Time-Triggered Ethernet (TTE) to thereby effectively improve the utilization ratio of network bandwidths in a mechanism of transmitting data based on the TTE. The invention will be described below in details with reference to the drawings. FIG. 2 illustrates a schematic diagram of a process of transmitting data based on a TTE according to a particular embodiment of the invention, and the process includes the following operations: Operation 201 : Each node receives a scheduling period table determined from time-triggered message, transmitted by a primary node. In the present invention, the primary node determines the scheduling period table from information about the number of bytes included in the time-triggered message transmitted by each node in one cycle, and information about physical link occupied by the time-triggered message. That is, the scheduling period table includes a correspondence relationship between information about each node, information about timeslot allocated to the node, and information about physical links occupied by the node for transmitting message in the timeslot. After the primary node generates the scheduling period table, the primary node transmits the scheduling period table to each node, so that each node can use the scheduling period table when transmitting an event-triggered message. Operation 202 : When a node has an event-triggered message to be transmitted, the node determines a physical link corresponding to the event-triggered message. Since each message includes information about a source address, and information about a destination address, for the transmission of the message, the physical link corresponding to the message can be determined from the message. Operation 203 : It is judged, according to the physical link, the timeslot allocation information, and the information about the physical link corresponding to each timeslot, stored in the scheduling period table, whether the physical link collides with a physical link corresponding to a current timeslot, and if not, then the process goes to the operation 204 ; otherwise, the process goes to the operation 205 . Here in the present invention, as long as at least one of nodes in the physical link is the same as one of nodes in the physical link corresponding to the current timeslot, it is determined that these two physical links collide. For example, the physical link corresponding to the event-triggered message is A-B-C, and the physical link corresponding to the current timeslot is a-b-c, and since none of the nodes in these two physical links are the same, it is determined that these two physical links do not collide; and when the physical link corresponding to the event-triggered message is A-B-C, and the physical link corresponding to the current timeslot is A-B-c, and since the nodes A and B are included in both of the physical links, it can be determined that these two physical links collide. Operation 204 : The event-triggered message is transmitted in the current timeslot. When the physical link corresponding to the event-triggered message does not collide with the physical link corresponding to current timeslot, the event-triggered message can be transmitted in the current timeslot, and since the physical link occupied by the event-triggered message does not collide with the physical link corresponding to the current timeslot, the event-triggered message can be transmitted without any influence on message transmission in the current timeslot. Operation 205 : The event-triggered message is not transmitted in the current timeslot. When the physical link occupied by the event-triggered message collides with the physical link corresponding to the current timeslot, the event-triggered message may not be transmitted to thereby guarantee message transmission in the current timeslot. In the present invention, the primary node determines the scheduling period table from time-triggered messages, where the scheduling period table includes the timeslot allocated to each node, and the physical links occupied by the node for transmitting the time-triggered message in the timeslot, and transmits the scheduling period table to each node. When the node has an event-triggered message to be transmitted, according to the locally stored scheduling period table and the physical link occupied by the event-triggered message, the node judges whether the physical link collides with the physical link corresponding to the current timeslot, and transmits the event-triggered message in the current timeslot when there is no collision. In the present invention, the primary node will not allocate timeslots separately for the event-triggered messages of the respective nodes, and when each node has an event-triggered message to be transmitted, the node can transmit the event-triggered message in the current timeslot as long as the physical link occupied by the event-triggered message does not collide with the physical link corresponding to the current timeslot to thereby effectively improve the efficiency of data transmission and the utilization ratio of network bandwidths. In the present invention, the primary node determines the scheduling period table from time-triggered messages transmitted by the respective nodes in one cycle. Here each node reports time-triggered message transmission request to the primary node, and here the transmission request carries information about the number of bytes included in time-triggered message transmitted by the node in one cycle, and information about source address and destination address of the time-triggered message. Upon reception of the transmission request transmitted by each node, the primary node determines a time required for transmitting the time-triggered message, according to the information about the number of bytes included in the time-triggered message carried in the transmission request, and allocates the timeslot to the node according to the time; and determines the physical link occupied by the time-triggered message according to the information about the source address and the destination address of the time-triggered message carried in the transmission request; and the primary node generates the scheduling period table according to the timeslot allocated to each node, and the physical link occupied by each node for transmitting the time-triggered message, and transmits the scheduling period table to each node. Each node receives and stores the scheduling period table transmitted by the primary node, and here the scheduling period table includes the information about the timeslot allocated to each node in one cycle, and the information about the physical link over which the node corresponding to the timeslot transmits the time-triggered message FIG. 3 illustrates a schematic structural diagram of the scheduling period table generated by the primary node according to the embodiment of the invention, and the scheduling period table includes the information about each node, the information about the timeslot allocated to the node, and the information about the physical link occupied by the node when transmitting the message in the timeslot. Particularly the information about the node can be identification information of the node, the information about the timeslot allocated to the node can identify start time and end time of the timeslot, and the information about the physical link can include identification information of respective nodes by which the physical link is formed. In the present invention, no timeslots will be reallocated for event-triggered messages, and when the node has an event-triggered message to be transmitted, the node transmits the event-triggered message upon determining that the physical link corresponding to the current timeslot does not collide with the physical link over which the node transmits the event-triggered message, according to the scheduling period table determined by the primary nodes for the transmission of time-triggered messages of each node. In the present invention, the current timeslot is a timeslot corresponding to a current event. When the respective nodes are transmitting the messages upon determining from the physical links that there is no confliction, if there are a large number of bytes included in the event-triggered message of some node, then such a problem may arise that the event-triggered message fails to be transmitted. Thus in the present invention, the information about the number of bytes included in the event-triggered message can be further taken into account in the present invention to thereby further improve the efficiency and the success ratio of data transmission as well as the utilization ratio of network bandwidths. FIG. 4 illustrates a particular implementation of a method for transmitting data based on the TTE according to an embodiment of the invention, and the process includes the following operations: Operation 401 : Each node receives a scheduling period table determined from time-triggered messages transmitted by a primary node. Operation 402 : When a node has an event-triggered message to be transmitted, the node determines a physical link corresponding to the event-triggered message. Here the physical link corresponding to the event-triggered message, which can also be referred to as a physical link occupied by the event-triggered message, is determined from information about a source address, and information about a destination address, in the event-triggered message. Operation 403 : It is judged, according to the physical link, the timeslot allocation information, and the information about the physical link corresponding to each timeslot, stored in the scheduling period table, whether the physical link collides with a physical link corresponding to a current timeslot, and if not, then the process goes to the operation 404 ; otherwise, the process goes to the operation 407 . Operation 404 : A remaining length of time of the current timeslot is determined from a current time, and an end time of the current timeslot. Operation 405 : It is judged, according to the number of bytes included in the event-triggered message and the remaining length of time of the current timeslot, whether the transmission of the event-triggered message can be completed in the remaining length of time, and if it is determined that the transmission of the event-triggered message can be completed in the remaining length of time, then the process goes to the operation 406 ; otherwise, the process goes to the operation 407 . Operation 406 : The event-triggered message is transmitted in the current timeslot. Operation 407 : The event-triggered message is not transmitted in the current timeslot. In order to effectively improve the efficiency of data transmission and the utilization ratio of bandwidths and to guarantee the success ratio of data transmission, in the above embodiment of the present invention, when the node has an event-triggered message to be transmitted, the node determines a physical link corresponding to the event-triggered message, and judges whether the physical link collides with the physical link for the current timeslot corresponding to the current time, according to the information recorded in the locally stored scheduling period table, and the node can further judge whether the remaining time of the current timeslot is sufficient to transmit the event-triggered message, upon determining that the physical link does not collide with the physical link corresponding to the current timeslot. The node determines the remaining length of time of the current timeslot according to the current time and the end time of the current timeslot, upon determining that the physical link does not collide with the physical link corresponding to the current timeslot; and the node judges, according to the number of bytes included in the event-triggered message, and the remaining length of time of the current timeslot, whether the transmission of the event-triggered message can be completed in the remaining length of time. Particularly since the number of bytes included in the event-triggered message is determined, the node can further determine a length of time for transmitting the event-triggered message including the number of bytes, and moreover since the remaining length of time of the current timeslot can also be determined, the length of time for transmitting event-triggered message can be compared with the remaining length of time, and if the length of time for transmitting the event-triggered message is longer than the remaining length of time, then it is determined that the transmission of the event-triggered message can not be completed in the remaining length of time; otherwise, if the length of time for transmitting the event-triggered message is no longer than the remaining length of time, then it is determined that the transmission of the event-triggered message can be completed in the remaining length of time. When the transmission of the event-triggered message can be completed in the remaining length of time, the event-triggered message is transmitted in the current timeslot. When it is determined that the physical link occupied by the event-triggered message does not collide with the physical link corresponding to the current timeslot, in order to guarantee the success ratio of transmitting the message, it is judged whether the event-triggered message can be transmitted in the current timeslot, according to the number of bytes included in the event-triggered message, and the remaining length of time of the current timeslot in the present invention. When the transmission of the event-triggered message can not be completed in the remaining length of time of the current timeslot, the event-triggered message may not be transmitted in the current timeslot. However in order to further improve the utilization ratio of network bandwidths and to effectively improve the efficiency of data transmission, it can be further judged whether the event-triggered message can be transmitted in the next timeslot or the timeslot after next of the current timeslot in the invention. FIG. 5 illustrates another particular implementation of a method for transmitting data based on a TTE according to an embodiment of the invention. Operation 501 : Each node receives a scheduling period table determined from time-triggered messages transmitted by a primary node. Operation 502 : When a node has an event-triggered message to be transmitted, the node determines a physical link corresponding to the event-triggered message. Here the physical link corresponding to the event-triggered message, which can also be referred to as a physical link occupied by the event-triggered message, is determined from information about a source address, and information about a destination address, in the event-triggered message. Operation 503 : It is judged, according to the physical link, the timeslot allocation information, and the information about the physical link corresponding to each timeslot, stored in the scheduling period table, whether the physical link collides with a physical link corresponding to a current timeslot, and if not, then the process goes to the operation 504 ; otherwise, the process goes to the operation 507 . Operation 504 : A remaining length of time of the current timeslot is determined from a current time, and an end time of the current timeslot. Operation 505 : It is judged, according to the number of bytes included in the event-triggered message and the remaining length of time of the current timeslot, whether the transmission of the event-triggered message can be completed in the remaining length of time, and if it is determined that the transmission of the event-triggered message can be completed in the remaining length of time, then the process goes to the operation 506 ; otherwise, the process goes to the operation 507 . Operation 506 : The time-triggered message is transmitted in the current timeslot. Operation 507 : A length of time for transmitting the event-triggered message is determined according to the number of bytes included in the event-triggered message. Operation 508 : Each corresponding timeslot in the length of time is determined, starting with the current time, according to the length of time and the length of each timeslot stored in the scheduling period table. Operation 509 : It is judged whether a physical link corresponding to each timeslot collides with the physical link corresponding to the event-triggered message, and if it is determined that the physical link corresponding to the each timeslot does not collide with the physical link corresponding to the event-triggered message, then the process goes to the operation 510 ; otherwise, the process goes to the operation 511 . Operation 510 : The event-triggered message is transmitted in the current timeslot if the physical link corresponding to the each timeslot does not collide with the physical link corresponding to the event-triggered message. Operation 511 : The time-triggered message is not transmitted in the current timeslot. In the above embodiment of the present invention, in order to effectively guarantee the transmission of the event-triggered message, when the transmission of the event-triggered message can not be completed in the remaining length of time of the current timeslot, if a next timeslot and a timeslot after next of the current timeslot are taken into account, the length of time for transmitting the event-triggered message is determined according to the number of bytes included in the event-triggered message, and each corresponding timeslot in the current length of time is determined, starting with the current time, according to the length of time and the length of each timeslot included in the scheduling period table. The event-triggered message is transmitted in the current timeslot if none of the physical links corresponding to the respective timeslots coincides with the physical link corresponding to the event-triggered message. The invention will be described below in details in connection with a particular embodiment thereof. Referring to FIG. 1 , the primary node determines the scheduling period table as depicted in Table below and transmits the scheduling period table to each node. Timeslot Corresponding physical link Node information information (ms) information PC1 0~10 Switch1, Switch2, Switch3 PC3 11~32  Switch3, Switch2 PC4 33~82  Switch4, Switch3 PC2 83~100 Switch2, Switch1 The scheduling period table above includes the timeslots allocated to the respective nodes, and the information about the physical links corresponding to the timeslots, in each scheduling cycle with the length of 100 ms. With the scheduling period table, when the PC 1 has an event-triggered message to be transmitted at the 34th ms in some scheduling cycle, the PC 1 determines the physical link corresponding to the event-triggered message according to the information about the source address, and the information about the destination address, included in the event-triggered message. For example, if the information about the source address included in the event-triggered message is the identification information of the PC 1 , and the information about the destination address included therein is the identification information of the PC 2 , the physical link corresponding to the event-triggered message is determined as the switch 1 to the switch 2 . At the 34th ms in the scheduling cycle, the corresponding current timeslot is the timeslot of 33 to 82 corresponding to the PC 4 , and the physical link corresponding to the current timeslot is the switch 4 to the switch 3 , so it is determined that the physical link of the switch 1 to the switch 2 corresponding to the event-triggered message does not collide with the physical link of the switch 4 to the switch 3 corresponding to the current timeslot, and then the PC 1 determines that the event-triggered message can be transmitted in the current timeslot. In order to further improve the utilization ratio of network bandwidths and the efficiency and success ratio of data transmission, in this embodiment, the PC 1 can further determine the length of time for transmitting the event-triggered message, and the remaining length of time of the current timeslot, for example, the length of time for transmitting the event-triggered message is 20 ms, and the remaining length of time of the current timeslot is 82−34=48 ms, so the remaining length 48 of time of the current timeslot is longer than the length 20 of time for transmitting the event-triggered message, and thus it is determined that the transmission of the event-triggered message can be completed in the remaining length of time, and the event-triggered message is transmitted in the current timeslot. If the number of bytes included in the event-triggered message is relatively large, and the length of time for transmitting the event-triggered message is 60 ms, then it is determined that the transmission of the event-triggered message can not be completed in the remaining length of time, and then in order to further improve the utilization ratio of network bandwidths, two corresponding timeslots, which are timeslots corresponding respectively to the PC 4 and the PC 2 , in the length of time 60 ms are determined starting with the current time, and physical links corresponding to these two timeslots are the switch 4 to the switch 3 and the switch 2 to the switch 1 respectively. It is judged whether the physical links corresponding to these two timeslots collide with the physical link of the switch 1 to the switch 2 corresponding to the event-triggered message, and since the physical link of the switch 2 to the switch 1 collides with the physical link of the switch 1 to the switch 2 , the event-triggered message can not be transmitted in the current timeslot. FIG. 6 illustrates a schematic structural diagram of a device node for transmitting data based on a time triggered Ethernet (TTE) according to an embodiment of the invention, and the node device includes: A receiving module 61 is configured to receive a scheduling period table determined from time-triggered messages transmitted by a primary node; A determining module 62 is configured, when there is an event-triggered message to be transmitted, to determine a physical link corresponding to the event-triggered message; A judging module 63 is configured to judge, according to the physical link, timeslot allocation information and information about physical link corresponding to each timeslot, stored in the scheduling period table, whether the physical link collides with a physical link corresponding to a current timeslot; and A transmitting module 64 is configured to transmit the event-triggered message in the current timeslot when the judging module determines that there is no collision. The transmitting module 64 is further configured to report a time-triggered message transmission request to the primary node, where the transmission request carries information about the number of bytes included in a time-triggered message transmitted by the device in one cycle, and information about a source address and a destination address of the time-triggered message; and The receiving module 61 is further configured to receive and store the scheduling period table transmitted by the primary node, where the scheduling period table includes the information about the timeslots allocated to each node in one cycle, and the information about the physical link over which the node corresponding to the timeslot transmits the time-triggered message. The judging module 63 is configured to determine sequentially for each node in the physical link whether the node is the same as each of nodes in the physical link corresponding to the current timeslot; and to determine that the physical link collides with the physical link corresponding to the current timeslot, when at least one of the nodes in the physical node is the same as the node in the physical link. The transmitting module 64 is configured to determine a remaining length of time of the current timeslot according to a current time and an end time of the current timeslot; to judge whether the transmission of the event-triggered message can be completed in the remaining length of time, according to the number of bytes included in the event-triggered message, and the remaining length of time of the current timeslot; and to transmit the event-triggered message in the current timeslot when the transmission of the event-triggered message can be completed in the remaining length of time. The transmitting module 64 is further configured, when the transmission of the event-triggered message can not be completed in the remaining length of time, to determine a length of time for transmitting the event-triggered message, according to the number of bytes included in the event-triggered message; to determine each corresponding timeslot in the length of time, starting with the current time, according to the length of time and the length of each timeslot stored in the scheduling period table; to judge whether a physical link corresponding to each timeslot collides with the physical link corresponding to the event-triggered message; and to transmit the event-triggered message in the current timeslot when the physical link corresponding to the each timeslot does not collide with the physical link corresponding to the event-triggered message. The embodiments of the present invention provide a method and node device for transmitting data based on a TTE, and in the method, the primary node determines a scheduling period table from time-triggered messages, and when each node has an event-triggered message to be transmitted, the node transmits the event-triggered message in the current timeslot upon determining from the information stored in the scheduling period table that a physical link occupied by the event-triggered message does not collide with a physical link corresponding to the current timeslot. In the present invention, the primary node will not allocate timeslots separately for the event-triggered messages of the respective nodes, and when each node has the event-triggered message to be transmitted, the node can transmit the event-triggered message in the current timeslot as long as the physical link occupied by the event-triggered message does not collide with the physical link corresponding to the current timeslot to thereby effectively improve the efficiency of data transmission and the utilization ratio of network bandwidths. Those skilled in the art shall appreciate that the embodiments of the invention can be embodied as a method, a system or a computer program product. Therefore the invention can be embodied in the form of an all-hardware embodiment, an all-software embodiment or an embodiment of software and hardware in combination. Furthermore the invention can be embodied in the form of a computer program product embodied in one or more computer useable storage mediums (including but not limited to a disk memory, a CD-ROM, an optical memory, etc.) in which computer useable program codes are contained. The invention has been described in a flow chart and/or a block diagram of the method, the device (system) and the computer program product according to the embodiments of the invention. It shall be appreciated that respective flows and/or blocks in the flow chart and/or the block diagram and combinations of the flows and/or the blocks in the flow chart and/or the block diagram can be embodied in computer program instructions. These computer program instructions can be loaded onto a general-purpose computer, a specific-purpose computer, an embedded processor or a processor of another programmable data processing device to produce a machine so that the instructions executed on the computer or the processor of the other programmable data processing device create means for performing the functions specified in the flow(s) of the flow chart and/or the block(s) of the block diagram. These computer program instructions can also be stored into a computer readable memory capable of directing the computer or the other programmable data processing device to operate in a specific manner so that the instructions stored in the computer readable memory create an article of manufacture including instruction means which perform the functions specified in the flow(s) of the flow chart and/or the block(s) of the block diagram, These computer program instructions can also be loaded onto the computer or the other programmable data processing device so that a series of operational steps are performed on the computer or the other programmable data processing device to create a computer implemented process so that the instructions executed on the computer or the other programmable device provide steps for performing the functions specified in the flow(s) of the flow chart and/or the block(s) of the block diagram. Although the preferred embodiments of the invention have been described, those skilled in the art benefiting from the underlying inventive concept can make additional modifications and variations to these embodiments. Therefore the appended claims are intended to be construed as encompassing the preferred embodiments and all the modifications and variations coming into the scope of the invention. Evidently those skilled in the art can make various modifications and variations to the invention without departing from the spirit and scope of the invention. Thus the invention is also intended to encompass these modifications and variations thereto so long as the modifications and variations come into the scope of the claims appended to the invention and their equivalents.

A time-triggered Ethernet (TTE)-based data transmission method and node device, solving the problem of wasting network bandwidth resources in the prior art during TTE-based data transmission; in the method, a main node determines a scheduling period table based on a time-triggered packet; when a node has a to-be-transmitted event-triggered packet, and the node determines, according to the information stored in the scheduling period table, that a physical link occupied by the event-triggered packet is not in conflict with a physical link corresponding to the current time slot, the node transmits the event-triggered packet in the current time slot. The main node does not need to separately allocate time for the event-triggered packet of each node. Therefore, when a node has a to-be-transmitted event-triggered packet, the node can transmit the event-triggered packet in the current time slot as long as the physical link occupied by the event-triggered packet is not in conflict with the physical link corresponding to the current time slot, thus effectively improving data transmission efficiency and network bandwidth utilization.

CROSS-REFERENCE TO RELATED APPLICATION [0001] This patent application is a continuation of, and claims priority to U.S. Patent Application No. 14/321,110, filed on Jul. 1, 2014, and entitled “AGGREGATION OF MOBILE DEVICE DATA FOR FACILITATION OF RULE-BASED ACTION”. The entirety of the foregoing application is hereby incorporated by reference herein. TECHNICAL FIELD [0002] This disclosure relates generally to aggregation of mobile device data, such as location data, e.g., via an indoor positioning system, to facilitate an action based on the aggregated mobile device data and rule(s) defined via a user interface. [0003] BACKGROUND [0004] Indoor position systems (IPSs) comprise a network of devices used to wirelessly locate objects or people inside a building. Instead of using satellites, an IPS relies on nearby anchors e.g., nodes with a known position), which either actively locate tags or provide ambient location or environmental context for devices to get sensed. These anchors can use different ways to determine positions of objects or people including: choke point concepts, grid concepts, long-range sensor concepts, angle of arrival, time of arrival, signal strength indication, or inertial measurements, or combinations thereof. The localized nature of an IPS has resulted in systems making use of various optical, radio, or even acoustic technologies. [0005] Most applications currently rely on global positioning system (GPS), and function poorly indoors as a result. Due to signal attenuation caused by construction materials, satellite based GPS signals lose significant power indoors decreasing coverage for receivers. In addition, multiple reflections at surfaces cause multi-path propagation, which can cause uncontrollable error. Indoor positioning is, however, a vehicle for the expansion of location-aware mobile computing indoors. [0006] Other IPS platforms can be integrated into the infrastructure of buildings, but this type of service is costly and labor intensive because it involves custom engineering at each location by assimilating and analyzing radio frequency (RF) measurement data, identifying and mapping radiation sources, and studying building area floor plans and obstructions. [0007] The above-described background relating to IPS systems is merely intended to provide a contextual overview, and is not intended to be exhaustive. Other contextual information may become further apparent upon review of the following detailed description. BRIEF DESCRIPTION OF THE DRAWINGS [0008] Non-limiting and non-exhaustive embodiments of the subject disclosure are described with reference to the following figures, wherein like reference numerals refer to like parts throughout the various views unless otherwise specified. [0009] FIG. 1 illustrates an example system for determining when a mobile device is within range of a network device and communicating mobile device data to the network based on a defined rule. [0010] FIG. 2 illustrates an example system for determining when multiple mobile devices are within range of a network device and communicating mobile device location data, in relation to each mobile device, to the network based on a defined rule. [0011] FIG. 3 illustrates an example system for determining when a mobile device is within range of a network device and communicating mobile device location data, representative of previous and current mobile device locations, to the network based on a defined rule. [0012] FIG. 4 illustrates an example system for several network devices associated with several locations communicating mobile device location data, representative of previous and current mobile device locations, to the network based on a defined rule. [0013] FIG. 5 illustrates an example flow diagram of a method for communicating mobile device data to the network and performing an action based on a defined rule. [0014] FIG. 6 illustrates an example flow diagram of a system for storing and communicating mobile device data to a network and performing an action based on a defined rule. [0015] FIG. 7 illustrates an example flow diagram of a computer readable storage medium for communicating mobile device data to a network and performing an action based on a defined rule in relation to a mobile device distance from another mobile device. [0016] FIG. 8 illustrates an example flow diagram of a system for storing and communicating mobile device data to a network and performing an action comprising sending a coupon. [0017] FIG. 9 illustrates an example flow diagram of a method for subscribing to a subscriber-based platform and generating user-defined rules. [0018] FIG. 10 illustrates an example flow diagram of mobile device entering into the range of a network device and the network device initiating an action based on a user-defined rule. [0019] FIG. 11 illustrates a block diagram of an example mobile handset operable to engage in a system architecture that facilitates secure wireless communication according to the embodiments described herein. [0020] FIG. 12 illustrates a block diagram of an example computer operable to engage in a system architecture that facilitates secure wireless communication according to the embodiments described herein. DETAILED DESCRIPTION [0021] In the following description, numerous specific details are set forth to provide a thorough understanding of various embodiments. One skilled in the relevant art will recognize, however, that the techniques described herein can be practiced without one or more of the specific details, or with other methods, components, materials, etc. In other instances, well-known structures, materials, or operations are not shown or described in detail to avoid obscuring certain aspects. [0022] Reference throughout this specification to “one embodiment,” or “an embodiment,” means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment. Thus, the appearances of the phrase “in one embodiment,” “in one aspect,” or “in an embodiment,” in various places throughout this specification are not necessarily all referring to the same embodiment. Furthermore, the particular features, structures, or characteristics may be combined in any suitable manner in one or more embodiments. [0023] As utilized herein, terms “component,” “system,” “interface,” and the like are intended to refer to a computer-related entity, hardware, software (e.g., in execution), and/or firmware. For example, a component can be a processor, a process running on a processor, an object, an executable, a program, a storage device, and/or a computer. By way of illustration, an application running on a server and the server can be a component. One or more components can reside within a process, and a component can be localized on one computer and/or distributed between two or more computers. [0024] Further, these components can execute from various computer readable media having various data structures stored thereon. The components can communicate via local and/or remote processes such as in accordance with a signal having one or more data packets (e.g., data from one component interacting with another component in a local system, distributed system, and/or across a network, e.g., the Internet, a local area network, a wide area network, etc. with other systems via the signal). [0025] As another example, a component can be an apparatus with specific functionality provided by mechanical parts operated by electric or electronic circuitry; the electric or electronic circuitry can be operated by a software application or a firmware application executed by one or more processors; the one or more processors can be internal or external to the apparatus and can execute at least a part of the software or firmware application. As yet another example, a component can be an apparatus that provides specific functionality through electronic components without mechanical parts; the electronic components can include one or more processors therein to execute software and/or firmware that confer(s), at least in part, the functionality of the electronic components. In an aspect, a component can emulate an electronic component via a virtual machine, e.g., within a cloud computing system. [0026] The words “exemplary” and/or “demonstrative” are used herein to mean serving as an example, instance, or illustration. For the avoidance of doubt, the subject matter disclosed herein is not limited by such examples. In addition, any aspect or design described herein as “exemplary” and/or “demonstrative” is not necessarily to be construed as preferred or advantageous over other aspects or designs, nor is it meant to preclude equivalent exemplary structures and techniques known to those of ordinary skill in the art. Furthermore, to the extent that the terms “includes,” “has,” “contains,” and other similar words are used in either the detailed description or the claims, such terms are intended to be inclusive—in a manner similar to the term “comprising” as an open transition word—without precluding any additional or other elements. [0027] As used herein, the term “infer” or “inference” refers generally to the process of reasoning about, or inferring states of, the system, environment, user, and/or intent from a set of observations as captured via events and/or data. Captured data and events can include user data, device data, environment data, data from sensors, sensor data, application data, implicit data, explicit data, etc. Inference can be employed to identify a specific context or action, or can generate a probability distribution over states of interest based on a consideration of data and events, for example. [0028] Inference can also refer to techniques employed for composing higher-level events from a set of events and/or data. Such inference results in the construction of new events or actions from a set of observed events and/or stored event data, whether the events are correlated in close temporal proximity, and whether the events and data come from one or several event and data sources. Various classification schemes and/or systems (e.g., support vector machines, neural networks, expert systems, Bayesian belief networks, fuzzy logic, and data fusion engines) can be employed in connection with performing automatic and/or inferred action in connection with the disclosed subject matter. [0029] In addition, the disclosed subject matter can be implemented as a method, apparatus, or article of manufacture using standard programming and/or engineering techniques to produce software, firmware, hardware, or any combination thereof to control a computer to implement the disclosed subject matter. The term “article of manufacture” as used herein is intended to encompass a computer program accessible from any computer-readable device, computer-readable carrier, or computer-readable media. For example, computer-readable media can include, but are not limited to, a magnetic storage device, e.g., hard disk; floppy disk; magnetic strip(s); an optical disk (e.g., compact disk (CD), a digital video disc (DVD), a Blu-ray Disc™ (BD)); a smart card; a flash memory device (e.g., card, stick, key drive); and/or a virtual device that emulates a storage device and/or any of the above computer-readable media. [0030] As an overview of various embodiments presented herein, to correct for the above identified deficiencies and other drawbacks of GPS networks, various embodiments are described herein to facilitate the use of IPS networks. [0031] For simplicity of explanation, the methods (or algorithms) are depicted and described as a series of acts. It is to be understood and appreciated that the various embodiments are not limited by the acts illustrated and/or by the order of acts. For example, acts can occur in various orders and/or concurrently, and with other acts not presented or described herein. Furthermore, not all illustrated acts may be required to implement the methods. In addition, the methods could alternatively be represented as a series of interrelated states via a state diagram or events. Additionally, the methods described hereafter are capable of being stored on an article of manufacture (e.g., a computer readable storage medium) to facilitate transporting and transferring such methodologies to computers. The term article of manufacture, as used herein, is intended to encompass a computer program accessible from any computer-readable device, carrier, or media, including a non-transitory computer readable storage medium. [0032] Utilizing a configurable IPS in conjunction with a wireless network and a user interface for creating rules can aid in a customer experience via their mobile devices. Described herein are systems, methods, articles of manufacture, and other embodiments or implementations that can facilitate usage of an IPS and associated wireless networks. The various embodiments can be implemented in connection with any type of device with a connection to a communications network (e.g., a wireless communications network, the Internet, or the like), such as a mobile handset, a computer, a handheld device, or the like. [0033] An IPS device can be used to send targeted messages to a customer's mobile device within a specific area or perimeter designated by a user device associated with a user identity, such as a business owner identity or administrator identity. The targeted messages can be sent via Wireless Fidelity (Wi-Fi) protocols or other RF protocols based on information that is defined by the user identity via the user device. User input associated with the user identity can be entered via a website, an application, or other graphical user interface (GUI). This process can allow the user to configure an IPS device to send custom messages based on entry or exit of a mobile device into or from designated areas of a specific location including, but not limited to, businesses or warehouses. Therefore, this process can reduce or eliminate the need for labor-intensive custom engineering generally associated with larger stores. This process can increase scalability and reduce costs for smaller business. The system can comprise an opt-in subscription-based service that can determine charges based on a number of defined rules created and/or the number of IPS devices utilized to create a version of the messaging platform. The subscription-based system can allow reception of Wi-Fi media access control (MAC) addresses along with respective targeted messages for each of the MAC addresses. [0034] Within the subscription-based platform, location-specific messages can be assigned and scheduled to respective locations via the GUI. Time or behavioral-based rules for disseminating the messages can also be set up via the GUI. The location data and traffic reports can be collected and stored by the IPS and sent to network device of a wireless network, where the location data and traffic reports can later be reviewed and analyzed via a user device. [0035] In one embodiment, a wireless network can communicate with an end-user device and a network device. User-defined rules can be sent from the end-user device to the network. The network can send those rules to the network device where the network device can perform an action based on the set of rules and a nearby mobile device. [0036] According to another embodiment, described herein is a method for determining that a mobile device is within range of a network device. The method can then initiate an action to be performed based on a defined rule. [0037] According to yet another embodiment, an article of manufacture, such as a computer readable storage medium or the like, can store instructions that, when executed by a computing device, can facilitate initiation of an action based on a mobile device being in range of a network device. The article of manufacture can also allow a user device to define rules that must be satisfied prior to the initiation of the action. [0038] Additionally, according to a further embodiment, described herein is a system that can facilitate a connection between a user device, a network device, and a mobile device for the purpose of initiating an action at the mobile device. The system can also facilitate a storing of location data of the mobile device. The system can include a display component or GUI that allows a user device for defining rules for initiating the action at the mobile device. The system can also include one or more servers in a cloud-computing environment that can store information about mobile devices and system preferences of a identity. [0039] These and other embodiments or implementations are described in more detail below with reference to the drawings. [0040] Referring now to FIG. 1 , illustrated is a system for determining when a mobile 108 device is within a range 106 of a network device 104 and communicating mobile device 108 data to the network 102 based on a defined rule. An end-user device 100 can be used to store or transmit data to the network 102 . The end-user device 100 can be any device that can connect to the network 102 including, but is not limited to, a mobile phone, a laptop, etc. The end-user device 100 can connect to the network 102 via any wireless means including, but not limited to, the internet, Wi-Fi, Bluetooth, 3G, 4G, or the like. [0041] A subscription-based platform, including a service or application, can be accessed via the end-user device 100 . The subscription-based platform can allow selection of rules at an end-user device 100 to apply to the network device 104 . The subscription-based platform can require a fee for opting into the service to allow setting of rules for the network devices 104 . For example, a rule can be set at the end-user device 100 which can define the range 106 of the network device 104 to be twenty feet. Thus, a mobile device 108 must be within twenty feet of the network device 104 before any communication can take place. The mobile device 108 can connect to the network 102 via the network device 104 by any wireless means including, but not limited to, the internet, Wi-Fi, Bluetooth, 3G, 4G, or the like. Other rules can also be defined at the end-user device 100 . For instance, the end-user device 100 can allow for setting a rule that allows a message to be sent to any mobile device 108 within the range 106 of the network device 104 . [0042] The message sent to the mobile device 108 can include, but is not limited to, text, video, coupons, etc. The message sent to the mobile device 108 can also prompt a mobile device user, namely a customer, to perform some action on the mobile device 108 . The network device 104 can receive data from the mobile device 108 including, but not limited to, network device-prompted responses, current mobile device 108 location data, previous mobile device 108 location data, time a mobile device 108 has spent in a specific location, etc. [0043] The network device 104 can also receive data from the mobile device 108 with regard to its distance from another mobile device 108 within the range 106 . The data received by the network device 104 can be stored at the network device 104 and/or forwarded to the network 102 . The network 102 can store the data received from the network device 104 and/or forward the data to the subscription-based platform. The subscription-based platform can allow an end-user to access and analyze the aggregated data at the end-user device 100 . [0044] Referring now to FIG. 2 , illustrated is a system for determining when multiple mobile devices 208 are within a range 206 of a network device 204 and communicating mobile device 208 location data, in relation to each mobile device 208 , to the network 202 based on a defined rule. An end-user device 200 can be used to store or transmit data to the network 202 . The end-user device 200 can be any device that can connect to the network 202 including, but not limited to, a mobile phone, a laptop, etc. The end-user device 200 can connect to the network 202 via any wireless means including, but not limited to, the internet, Wi-Fi, Bluetooth, 3G, 4G, or the like. [0045] A subscription-based platform, including a service or application, can be accessed via the end-user device 200 . The subscription-based platform can allow selection of rules at an end-user device 200 to apply to the network device 204 . The subscription-based platform can require a fee for opting into the service to set rules for the network devices 204 . For example, the end-user device 200 can allow for defining a range 206 of the network device to be twenty feet. Thus, in the previous scenario, a mobile device 208 must be within twenty feet of the network device 204 before any communication can take place. The mobile device 208 can connect to the network 202 via the network device 204 by any wireless means including, but not limited to, the internet, Wi-Fi, Bluetooth, 3G, 4G, or the like. Other rules can also be defined at the end-user device 200 . For instance, the end-user device 200 can allow for setting a rule to have a message sent to any mobile device 208 within the range 206 of the network device 204 . [0046] The message sent to the mobile device 208 can include, but is not limited to, text, video, coupons, etc. The message sent to the mobile device 208 can also prompt a mobile device user, namely a customer, to perform some action at the mobile device 208 . The network device 204 can receive data from the mobile device 208 including, but not limited to, network device-prompted responses, current mobile device 208 location data, previous mobile device 208 location data, time a mobile device 208 has spent in a specific location, etc. [0047] The network device 204 can also receive data from the mobile device 208 with regard to its distance from other mobile devices 208 within the range 206 . Data relating to a mobile device's 208 distances from other mobile devices 208 can be used to determine customer habits based on location information. The data received by the network device 204 can be stored at the network device 204 and/or forwarded to the network 202 . The network 202 can store the data received from the network device 204 and/or forward the data to the subscription-based platform. The subscription-based platform can allow for access and analysis of the aggregated data from the end-user device 200 . [0048] Referring now to FIG. 3 , illustrated is a system for determining when a mobile device 308 is within a range 306 of a network device 304 and communicating mobile device 308 location data, representative of previous and current mobile device locations, to the network based on a defined rule. An end-user device 300 can be used to store or transmit data to the network 302 . The end-user device 300 can be any device that can connect to the network 302 including, but not limited to, a mobile phone, a laptop, etc. The end-user device 300 can connect to the network 302 via any wireless means including, but not limited to, the internet, Wi-Fi, Bluetooth, 3G, 4G, or the like. [0049] A subscription-based platform, including a service or application, can be accessed via the end-user device 300 . The subscription-based platform can allow selection of rules at an end-user device 300 to apply to the network device 304 . The subscription-based platform can require a fee for opting into the service to set rules for the network devices 304 . For example, the end-user device 300 can allow for defining a range 306 of the network device to be twenty feet. Thus, in the previous scenario, a mobile device 308 must be within twenty feet of the network device 304 before any communication can take place. The mobile device 308 can connect to the network 302 via the network device 304 by any wireless means including, but not limited to, the internet, Wi-Fi, Bluetooth, 3G, 4G, or the like. Other rules can also be defined at the end-user device 300 . For instance, the end-user device 300 can allow for setting a rule to have a message sent to any mobile device 308 within the range 306 of the network device 304 . [0050] The message sent to the mobile device 308 can include, but is not limited to, text, video, coupons, etc. The message sent to the mobile device 308 can also prompt a mobile device user, namely a customer, to perform some action at the mobile device 308 . The network device 304 can receive data from the mobile device 308 including, but not limited to, network device-prompted responses, current mobile device 308 location data, previous mobile device 308 location data, time a mobile device 308 has spent in a specific location, etc. In FIG. 3 , the network device 304 can communicate to the network 302 that the mobile device 308 was located at Location A before proceeding to Location B and then to Location C. [0051] The network device 304 can also receive data from the mobile device 308 with regard to its distance from other mobile devices 308 within the range 306 . Data relating to a mobile device's 308 distances from other mobile devices 308 can be used to determine customer habits based on location information. The data received by the network device 304 can be stored at the network device 304 and/or forwarded to the network 302 . The network 302 can store the data received from the network device 304 and/or forward the data to the subscription-based platform. The subscription-based platform can allow an end-user to access and analyze the aggregated data from the end-user device 300 . [0052] Referring now to FIG. 4 , illustrated is a system for several network devices 404 A, 404 B, 404 C associated with several locations (Location A, Location B, and Location C) communicating mobile device 408 location data, representative of previous and current mobile device 408 locations, to the network 402 based on a defined rule. An end-user device 400 can be used to store or transmit data to the network 402 . The end-user device 400 can be any device that can connect to the network 402 including, but not limited to, a mobile phone, a laptop, etc. The end-user device 400 can connect to the network 402 via any wireless means including, but not limited to, the internet, Wi-Fi, Bluetooth, 3G, 4G, or the like. [0053] A subscription-based platform, including a service or application, can be accessed via the end-user device 400 . The subscription-based platform can allow selection of rules at an end-user device 400 to apply to the network devices 404 A, 404 B, 404 C. The subscription-based platform can require a fee for opting into the service to allow for setting rules for the network devices 404 A, 404 B, 404 C. For example, a rule may be set at the end-user device 400 to define a range 406 A, 406 B, 406 C of the network devices 404 A, 404 B, 404 C to be twenty feet. Thus, in the previous example, a mobile device 408 must be within twenty feet of the network devices 404 A, 404 B, 404 C before any communication can take place. The mobile device 408 can connect to the network 402 via the network devices 404 A, 404 B, 404 C by any wireless means including, but not limited to, the internet, Wi-Fi, Bluetooth, 3G, 4G, or the like. Other rules can also be defined at the end-user device 400 . For instance, a rule can be set at the end-user device 400 to have a message sent to any mobile device 408 within the ranges 406 A 406 B 406 C of the network devices 404 A 404 B 404 C. [0054] The message sent to the mobile device 408 can include, but is not limited to, text, video, coupons, etc. The message sent to the mobile device 408 can also prompt a mobile device user, namely a customer, to perform some action at the mobile device 408 . The network devices 404 A, 404 B, 404 C can receive data from the mobile device 408 including, but not limited to, network device-prompted responses, current mobile device 408 location data, previous mobile device 408 location data, time a mobile device 408 has spent in a specific location, etc. In FIG. 4 , each network device 404 A, 404 B, 404 C can communicate current and past location data of the mobile device 408 to the network 402 . Network devices 404 A, 404 B, 404 C can also communicate between each other. For instance, network device 404 A can communicate to network device 404 B that the mobile device 408 was at Location A before proceeding to Location B. Likewise, network device 404 B can communicate to network device 404 C that the mobile device 408 was at Location B before proceeding to Location C. [0055] The network devices 404 A, 404 B, 404 C can also receive data from the mobile device 408 with regard to its distance from other mobile devices 408 within the ranges 406 A, 406 B, 406 C. Data relating to a mobile device's 408 distances from other mobile devices 408 can be used to determine customer habits based on location information. The data received by the network devices 404 A, 404 B, 404 C can be stored at each respective network device 404 A, 404 B, 404 C and/or forwarded to the network 402 . The network 402 can store the data received from the network devices 404 A, 404 B, 404 C and/or forward the data to the subscription-based platform. The subscription-based platform can allow for access and analysis of the aggregated data from the end-user device 400 . [0056] Referring now to FIG. 5 , illustrated is a schematic process flow diagram of a method for communicating mobile device data to a network and performing an action based on a defined rule. Element 500 can use store instruction data received from another network device based on subscription data defining a set of defined rules. A subscription-based platform, including a service or application, can be accessed via an end-user device. The subscription-based platform can allow for a determination of which rules to apply to the network device of element 500 . The subscription-based platform can require a fee for opting into the service to set rules for the network device of element 500 . Element 502 can store location data received from a mobile device comprising distance data, representative of a distance of the mobile device from the network device. For example, the end-user device can allow for setting a rule to define a range of the network device to be twenty feet. Thus, based on the previous example, a mobile device must be within twenty feet of the network device before any communication can take place. The mobile device can connect to the network via the network device by any wireless means including, but not limited to, the internet, Wi-Fi, Bluetooth, 3G, 4G, or the like. Such communication can then be stored via element 502 . [0057] Element 504 can initiate an action based on the location data being determined to indicate that the mobile device is within a defined distance of the network device. The action of element 504 can include, but is not limited to, sending a message, which was generated at the end-user device, to the mobile device within the range of the network device. The message sent to the mobile device can include, but is not limited to, text, video, coupons, etc. The message sent to the mobile device can also prompt a mobile device user, namely a customer, to perform some action at the mobile device. [0058] Element 506 can send the location data received from the mobile device to the other network device. The data received by the network device at element 506 can be stored at network device and/or forwarded to the network. The network can store the data received from the network device and/or forward the data to the subscription-based platform of element 500 . The subscription-based platform can allow for access and analysis of the aggregated data from the other network device. [0059] Referring now to FIG. 6 , illustrated is a schematic process flow diagram of a system for storing and communicating mobile device data to a network and performing an action based on a defined rule. Element 600 can receive subscription data comprising a set of defined rules related to a set of conditions. A subscription-based platform, including a service or application, can be accessed via an end-user device. The subscription-based platform can allow for a determination of which rules to apply to a network device. The subscription-based platform can require a fee for opting into the service to allow for setting of rules for the network device. Element 602 can store the subscription data of element 600 comprising the set of defined rules related to the set of conditions. For example, a rule can be set at the end-user device to define a range of the network device to be twenty feet. Thus, based on the previous example, a mobile device must be within twenty feet of the network device before any communication can take place. The mobile device can connect to the network via the network device by any wireless means including, but not limited to, the internet, Wi-Fi, Bluetooth, 3G, 4G, or the like. [0060] Element 604 can receive location data of a mobile device in response to the mobile device being determined to be in the range of the network device as determined by element 600 . Element 606 can determine that a condition, of the set of conditions, has been satisfied, wherein the condition is related to other location data of the mobile device. The location data of the mobile device can include, but is not limited to, network device-prompted responses, current mobile device location data, previous mobile device location data, time a mobile device has spent in a specific location, etc. [0061] Element 608 can perform an action in response to a determination that the condition of the other location data of element 606 is satisfied. The action of element 608 can include, but is not limited to, sending a message, which was generated at the end-user device, to the mobile device within the range of the network device. The message sent to the mobile device can include, but is not limited to, text, video, coupons, etc. The message sent to the mobile device can also prompt a mobile device user, namely a customer, to perform some action at the mobile device. [0062] Referring now to FIG. 7 , illustrated is a schematic process flow diagram of a computer readable storage medium for communicating mobile device data to a network and performing an action based on a defined rule in relation to a mobile device distance from another mobile device. Element 700 can receive subscription data comprising a set of defined rules related to a set of conditions. A subscription-based platform, including a service or application, can be accessed via an end-user device. The subscription-based platform can allow an for a determination of which rules to apply to a network device. The subscription-based platform can require a fee for opting into the service to set rules for the network device. [0063] Element 702 can store the subscription data of element 700 comprising the set of defined rules related to the set of conditions. For example a rule to defining a range of the network device to be twenty feet can be set at the end-user device. Thus, based on the previous example, a mobile device must be within twenty feet of the network device before any communication can take place. The mobile device can connect to the network via the network device by any wireless means including, but not limited to, the internet, Wi-Fi, Bluetooth, 3G, 4G, or the like. Element 704 can receive a first location data of a first mobile device in response to the first mobile device being determined to be in a first range of a first network device. Element 706 can receive a second location data of a second mobile device in response to the second mobile device being determined to be in a second range of a second network device. Element 708 can determine that a condition, of the set of conditions, has been satisfied, wherein the condition is related to a distance between the first mobile device and the second mobile device. The network device can receive distance data from each mobile device within range of their respective network devices. Data relative to a mobile device's distance from other mobile devices can be used to determine customer habits based on location information. [0064] Referring now to FIG. 8 , illustrated is a schematic process flow diagram of a system for storing and communicating mobile device data to a network and performing an action comprising sending a coupon. Element 800 can receive subscription data comprising a set of defined rules related to a set of conditions. A subscription-based platform, including a service or application, can be accessed via an end-user device. The subscription-based platform can allow for a determination of which rules to apply to a network device. The subscription-based platform can require a fee for opting into the service to set rules for the network device. Element 802 can store the subscription data of element 800 comprising the set of defined rules related to the set of conditions. For example, a rule to define a range of the network device to be twenty feet can be set at the end-user device. Thus, a mobile device must be within twenty feet of the network device before any communication can take place. The mobile device can connect to the network via the network device by any wireless means including, but not limited to, the internet, Wi-Fi, Bluetooth, 3G, 4G, or the like. [0065] Element 804 can receive location data of a mobile device in response to the mobile device being determined to be in the range of the network device as determined by element 800 . Element 806 can determine that a condition, of the set of conditions, has been satisfied, wherein the condition is related to other location data of the mobile device. The location data of the mobile device can include, but is not limited to, network device-prompted responses, current mobile device location data, previous mobile device location data, time a mobile device has spent in a specific location, etc. [0066] Element 808 can perform an action in response to a determination that the condition of the other location data of element 806 is satisfied. The action of element 808 can include, but is not limited to, sending a message, which was generated at the end-user device, to the mobile device within the range of the network device. The message sent to the mobile device can include, but is not limited to, text, video, coupons, etc. The message sent to the mobile device can also prompt a mobile device user, namely a customer, to perform some action at the mobile device. [0067] Referring now to FIG. 9 , illustrated is a schematic process flow diagram of a method for subscribing to a subscriber-based platform and generating user-defined rules. The process can start at element 900 . At element 902 an administrator can enable and positions radiation sources strategically in the respective areas for message delivery. Element 904 can allow the administrator to subscribe on a web site or other application messaging service via an end-user device. The end-user device can be used to store or transmit data to the network. The end-user device can be any device that can connect to the network including, but not limited to, a mobile phone, a laptop, etc. The end-user device can connect to the network via any wireless means including, but not limited to, the internet, Wi-Fi, Bluetooth, 3G, 4G, or the like. The subscription-based platform, including a service or application, can be accessed via the end-user device. The subscription-based platform can allow for a determination of which rules to apply to the network device. At element 906 the subscriber can enter identifying information for the radiation sources including, but not limited to, MAC address, service set identification (SSID), identification number, etc. The subscription-based platform can require a fee for opting into the service to set rules for the network devices. [0068] The subscriber can enter custom messages for devices entering/exiting each radiation source at element 908 . The message sent to the mobile device can include, but is not limited to, text, video, coupons, etc. The message sent to the mobile device can also prompt a mobile device user, namely a customer, to perform some action at the mobile device. The mobile device can connect to a network via the network device by any wireless means including, but not limited to, the internet, Wi-Fi, Bluetooth, 3G, 4G, or the like. At element 910 , the subscriber can enter other pertinent information such as schedules for messaging, class of devices to message, etc. The process can end at element 912 . [0069] Referring now to FIG. 10 , illustrated is a schematic process flow diagram of mobile device entering into a range of a network device and the network device initiating an action based on a user-defined rule. The process can start at element 1000 . A mobile device can load or already has a client/service running at element 1002 . At element 1004 the mobile device can enter a general region of a target area location (e.g. location area code (LAC)/routing area code (RAC)) and can trigger download of target area location information in the general region. At element 1006 the mobile device can enter the target area covered by a radiation source. The mobile device can connect to a network via the network device by any wireless means including, but not limited to, the internet, Wi-Fi, Bluetooth, 3G, 4G, or the like. [0070] At element 1008 , an application or service running on the mobile device can recognize a radiation point as the target area by a MAC address or other identification. Element 1010 can comprise a decision where the system can determine whether the mobile device is eligible to receive a message. If the system determines that the mobile device is not eligible to receive the message, then the process can end at element 1018 . If the system determines that the mobile device is eligible to receive the message, then the process can move to element 1012 where the application can locate and display the appropriate message on the mobile device. The message sent to the mobile device can prompt a mobile device user, namely a customer, to perform some action at the mobile device. At element 1014 actions (read message/clicked on message, etc.) of the mobile device user can be noted and uploaded to a server. The network device can receive data from the mobile device including, but not limited to, network device-prompted responses, current mobile device location data, previous mobile device location data, time a mobile device has spent in a specific location, etc. At element 1016 the mobile device can be counted and categorized (messaged/not messaged/etc.) The process can end at element 1018 . [0071] Referring now to FIG. 11 , illustrated is a schematic block diagram of an exemplary end-user device such as a mobile device 1100 capable of connecting to a network in accordance with some embodiments described herein. Although a mobile handset 1100 is illustrated herein, it will be understood that other devices can be a mobile device, and that the mobile handset 1100 is merely illustrated to provide context for the embodiments of the innovation described herein. The following discussion is intended to provide a brief, general description of an example of a suitable environment 1100 in which the various embodiments can be implemented. While the description includes a general context of computer-executable instructions embodied on a computer readable storage medium, those skilled in the art will recognize that the innovation also can be implemented in combination with other program modules and/or as a combination of hardware and software. [0072] Generally, applications (e.g., program modules) can include routines, programs, components, data structures, etc., that perform particular tasks or implement particular abstract data types. Moreover, those skilled in the art will appreciate that the methods described herein can be practiced with other system configurations, including single-processor or multiprocessor systems, minicomputers, mainframe computers, as well as personal computers, hand-held computing devices, microprocessor-based or programmable consumer electronics, and the like, each of which can be operatively coupled to one or more associated devices. [0073] A computing device can typically include a variety of computer-readable media. Computer readable media can be any available media that can be accessed by the computer and includes both volatile and non-volatile media, removable and non-removable media. By way of example and not limitation, computer-readable media can comprise computer storage media and communication media. Computer storage media can include volatile and/or non-volatile media, removable and/or non-removable media implemented in any method or technology for storage of information, such as computer-readable instructions, data structures, program modules or other data. Computer storage media can include, but is not limited to, RAM, ROM, EEPROM, flash memory or other memory technology, CD ROM, digital video disk (DVD) or other optical disk storage, magnetic cassettes, magnetic tape, magnetic disk storage or other magnetic storage devices, or any other medium which can be used to store the desired information and which can be accessed by the computer. [0074] Communication media typically embodies computer-readable instructions, data structures, program modules or other data in a modulated data signal such as a carrier wave or other transport mechanism, and includes any information delivery media. The term “modulated data signal” means a signal that has one or more of its characteristics set or changed in such a manner as to encode information in the signal. By way of example, and not limitation, communication media includes wired media such as a wired network or direct-wired connection, and wireless media such as acoustic, RF, infrared and other wireless media. Combinations of the any of the above should also be included within the scope of computer-readable media. [0075] The handset 1100 includes a processor 1102 for controlling and processing all onboard operations and functions. A memory 1104 interfaces to the processor 1102 for storage of data and one or more applications 1106 (e.g., a video player software, user feedback component software, etc.). Other applications can include voice recognition of predetermined voice commands that facilitate initiation of the user feedback signals. The applications 1106 can be stored in the memory 1104 and/or in a firmware 1108 , and executed by the processor 1102 from either or both the memory 1104 or/and the firmware 1108 . The firmware 1108 can also store startup code for execution in initializing the handset 1100 . A communications component 1110 interfaces to the processor 1102 to facilitate wired/wireless communication with external systems, e.g., cellular networks, VoIP networks, and so on. Here, the communications component 1110 can also include a suitable cellular transceiver 1111 (e.g., a GSM transceiver) and/or an unlicensed transceiver 1113 (e.g., WiFi, WiMax) for corresponding signal communications. The handset 1100 can be a device such as a cellular telephone, a PDA with mobile communications capabilities, and messaging-centric devices. The communications component 1110 also facilitates communications reception from terrestrial radio networks (e.g., broadcast), digital satellite radio networks, and Internet-based radio services networks. [0076] The handset 1100 includes a display 1112 for displaying text, images, video, telephony functions (e.g., a Caller ID function), setup functions, and for user input. For example, the display 1112 can also be referred to as a “screen” that can accommodate the presentation of multimedia content (e.g., music metadata, messages, wallpaper, graphics, etc.). The display 1112 can also display videos and can facilitate the generation, editing and sharing of video quotes. A serial I/O interface 1114 is provided in communication with the processor 1102 to facilitate wired and/or wireless serial communications (e.g., USB, and/or IEEE 1394) through a hardwire connection, and other serial input devices (e.g., a keyboard, keypad, and mouse). This supports updating and troubleshooting the handset 1100 , for example. Audio capabilities are provided with an audio I/O component 1116 , which can include a speaker for the output of audio signals related to, for example, indication that the user pressed the proper key or key combination to initiate the user feedback signal. The audio I/O component 1116 also facilitates the input of audio signals through a microphone to record data and/or telephony voice data, and for inputting voice signals for telephone conversations. [0077] The handset 1100 can include a slot interface 1118 for accommodating a SIC (Subscriber Identity Component) in the form factor of a card Subscriber Identity Module (SIM) or universal SIM 1120 , and interfacing the SIM card 1120 with the processor 1102 . However, it is to be appreciated that the SIM card 1120 can be manufactured into the handset 1100 , and updated by downloading data and software. [0078] The handset 1100 can process IP data traffic through the communication component 1110 to accommodate IP traffic from an IP network such as, for example, the Internet, a corporate intranet, a home network, a person area network, etc., through an ISP or broadband cable provider. Thus, VoIP traffic can be utilized by the handset 800 and IP-based multimedia content can be received in either an encoded or decoded format. [0079] A video processing component 1122 (e.g., a camera) can be provided for decoding encoded multimedia content. The video processing component 1122 can aid in facilitating the generation, editing and sharing of video quotes. The handset 1100 also includes a power source 1124 in the form of batteries and/or an AC power subsystem, which power source 1124 can interface to an external power system or charging equipment (not shown) by a power I/O component 1126 . [0080] The handset 1100 can also include a video component 1130 for processing video content received and, for recording and transmitting video content. For example, the video component 1130 can facilitate the generation, editing and sharing of video quotes. A location tracking component 1132 facilitates geographically locating the handset 1100 . As described hereinabove, this can occur when the user initiates the feedback signal automatically or manually. A user input component 1134 facilitates the user initiating the quality feedback signal. The user input component 1134 can also facilitate the generation, editing and sharing of video quotes. The user input component 1134 can include such conventional input device technologies such as a keypad, keyboard, mouse, stylus pen, and/or touch screen, for example. [0081] Referring again to the applications 1106 , a hysteresis component 1136 facilitates the analysis and processing of hysteresis data, which is utilized to determine when to associate with the access point. A software trigger component 1138 can be provided that facilitates triggering of the hysteresis component 1138 when the Wi-Fi transceiver 1113 detects the beacon of the access point. A SIP client 1140 enables the handset 1100 to support SIP protocols and register the subscriber with the SIP registrar server. The applications 1106 can also include a client 1142 that provides at least the capability of discovery, play and store of multimedia content, for example, music. [0082] The handset 1100 , as indicated above related to the communications component 810 , includes an indoor network radio transceiver 1113 (e.g., Wi-Fi transceiver). This function supports the indoor radio link, such as IEEE 802.11, for the dual-mode GSM handset 1100 . The handset 1100 can accommodate at least satellite radio services through a handset that can combine wireless voice and digital radio chipsets into a single handheld device. [0083] Referring now to FIG. 12 , there is illustrated a block diagram of a computer 1200 operable to execute a system architecture that facilitates establishing a transaction between an entity and a third party. The computer 1200 can provide networking and communication capabilities between a wired or wireless communication network and a server and/or communication device. In order to provide additional context for various aspects thereof, FIG. 12 and the following discussion are intended to provide a brief, general description of a suitable computing environment in which the various aspects of the innovation can be implemented to facilitate the establishment of a transaction between an entity and a third party. While the description above is in the general context of computer-executable instructions that can run on one or more computers, those skilled in the art will recognize that the innovation also can be implemented in combination with other program modules and/or as a combination of hardware and software. [0084] Generally, program modules include routines, programs, components, data structures, etc., that perform particular tasks or implement particular abstract data types. Moreover, those skilled in the art will appreciate that the inventive methods can be practiced with other computer system configurations, including single-processor or multiprocessor computer systems, minicomputers, mainframe computers, as well as personal computers, hand-held computing devices, microprocessor-based or programmable consumer electronics, and the like, each of which can be operatively coupled to one or more associated devices. [0085] The illustrated aspects of the innovation can also be practiced in distributed computing environments where certain tasks are performed by remote processing devices that are linked through a communications network. In a distributed computing environment, program modules can be located in both local and remote memory storage devices. [0086] Computing devices typically include a variety of media, which can include computer-readable storage media or communications media, which two terms are used herein differently from one another as follows. [0087] Computer-readable storage media can be any available storage media that can be accessed by the computer and includes both volatile and nonvolatile media, removable and non-removable media. By way of example, and not limitation, computer-readable storage media can be implemented in connection with any method or technology for storage of information such as computer-readable instructions, program modules, structured data, or unstructured data. Computer-readable storage media can include, but are not limited to, RAM, ROM, EEPROM, flash memory or other memory technology, CD-ROM, digital versatile disk (DVD) or other optical disk storage, magnetic cassettes, magnetic tape, magnetic disk storage or other magnetic storage devices, or other tangible and/or non-transitory media which can be used to store desired information. Computer-readable storage media can be accessed by one or more local or remote computing devices, e.g., via access requests, queries or other data retrieval protocols, for a variety of operations with respect to the information stored by the medium. [0088] Communications media can embody computer-readable instructions, data structures, program modules or other structured or unstructured data in a data signal such as a modulated data signal, e.g., a carrier wave or other transport mechanism, and includes any information delivery or transport media. The term “modulated data signal” or signals refers to a signal that has one or more of its characteristics set or changed in such a manner as to encode information in one or more signals. By way of example, and not limitation, communication media include wired media, such as a wired network or direct-wired connection, and wireless media such as acoustic, RF, infrared and other wireless media. [0089] With reference to FIG. 12 , implementing various aspects described herein with regards to the end-user device can include a computer 1200 , the computer 1200 including a processing unit 1204 , a system memory 1206 and a system bus 1208 . The system bus 1208 couples system components including, but not limited to, the system memory 1206 to the processing unit 1204 . The processing unit 1204 can be any of various commercially available processors. Dual microprocessors and other multi processor architectures can also be employed as the processing unit 1204 . [0090] The system bus 1208 can be any of several types of bus structure that can further interconnect to a memory bus (with or without a memory controller), a peripheral bus, and a local bus using any of a variety of commercially available bus architectures. The system memory 1206 includes read-only memory (ROM) 1210 and random access memory (RAM) 1212 . A basic input/output system (BIOS) is stored in a non-volatile memory 1210 such as ROM, EPROM, EEPROM, which BIOS contains the basic routines that help to transfer information between elements within the computer 1200 , such as during start-up. The RAM 1212 can also include a high-speed RAM such as static RAM for caching data. [0091] The computer 1200 further includes an internal hard disk drive (HDD) 1214 (e.g., EIDE, SATA), which internal hard disk drive 1214 can also be configured for external use in a suitable chassis (not shown), a magnetic floppy disk drive (FDD) 1216 , (e.g., to read from or write to a removable diskette 1218 ) and an optical disk drive 1220 , (e.g., reading a CD-ROM disk 1222 or, to read from or write to other high capacity optical media such as the DVD). The hard disk drive 1214 , magnetic disk drive 1216 and optical disk drive 1211 can be connected to the system bus 1208 by a hard disk drive interface 1224 , a magnetic disk drive interface 1226 and an optical drive interface 1228 , respectively. The interface 1224 for external drive implementations includes at least one or both of Universal Serial Bus (USB) and IEEE 1294 interface technologies. Other external drive connection technologies are within contemplation of the subject innovation. [0092] The drives and their associated computer-readable media provide nonvolatile storage of data, data structures, computer-executable instructions, and so forth. For the computer 1200 the drives and media accommodate the storage of any data in a suitable digital format. Although the description of computer-readable media above refers to a HDD, a removable magnetic diskette, and a removable optical media such as a CD or DVD, it should be appreciated by those skilled in the art that other types of media which are readable by a computer 1200 , such as zip drives, magnetic cassettes, flash memory cards, cartridges, and the like, can also be used in the exemplary operating environment, and further, that any such media can contain computer-executable instructions for performing the methods of the disclosed innovation. [0093] A number of program modules can be stored in the drives and RAM 1212 , including an operating system 1230 , one or more application programs 1232 , other program modules 1234 and program data 1236 . All or portions of the operating system, applications, modules, and/or data can also be cached in the RAM 1212 . It is to be appreciated that the innovation can be implemented with various commercially available operating systems or combinations of operating systems. [0094] A user can enter commands and information into the computer 1200 through one or more wired/wireless input devices, e.g., a keyboard 1238 and a pointing device, such as a mouse 1240 . Other input devices (not shown) may include a microphone, an IR remote control, a joystick, a game pad, a stylus pen, touch screen, or the like. These and other input devices are often connected to the processing unit 1204 through an input device interface 1242 that is coupled to the system bus 1208 , but can be connected by other interfaces, such as a parallel port, an IEEE 2394 serial port, a game port, a USB port, an IR interface, etc. [0095] A monitor 1244 or other type of display device is also connected to the system bus 1208 through an interface, such as a video adapter 1246 . In addition to the monitor 1244 , a computer 1200 typically includes other peripheral output devices (not shown), such as speakers, printers, etc. [0096] The computer 1200 can operate in a networked environment using logical connections by wired and/or wireless communications to one or more remote computers, such as a remote computer(s) 1248 . The remote computer(s) 1248 can be a workstation, a server computer, a router, a personal computer, portable computer, microprocessor-based entertainment device, a peer device or other common network node, and typically includes many or all of the elements described relative to the computer, although, for purposes of brevity, only a memory/storage device 1250 is illustrated. The logical connections depicted include wired/wireless connectivity to a local area network (LAN) 1252 and/or larger networks, e.g., a wide area network (WAN) 1254 . Such LAN and WAN networking environments are commonplace in offices and companies, and facilitate enterprise-wide computer networks, such as intranets, all of which may connect to a global communications network, e.g., the Internet. [0097] When used in a LAN networking environment, the computer 1200 is connected to the local network 1252 through a wired and/or wireless communication network interface or adapter 1256 . The adapter 1256 may facilitate wired or wireless communication to the LAN 1252 , which may also include a wireless access point disposed thereon for communicating with the wireless adapter 1256 . [0098] When used in a WAN networking environment, the computer 1200 can include a modem 1258 , or is connected to a communications server on the WAN 1254 , or has other means for establishing communications over the WAN 1254 , such as by way of the Internet. The modem 1258 , which can be internal or external and a wired or wireless device, is connected to the system bus 1208 through the serial port interface 1242 . In a networked environment, program modules depicted relative to the computer, or portions thereof, can be stored in the remote memory/storage device 1250 . It will be appreciated that the network connections shown are exemplary and other means of establishing a communications link between the computers can be used. [0099] The computer is operable to communicate with any wireless devices or entities operatively disposed in wireless communication, e.g., a printer, scanner, desktop and/or portable computer, portable data assistant, communications satellite, any piece of equipment or location associated with a wirelessly detectable tag (e.g., a kiosk, news stand, restroom), and telephone. This includes at least WiFi and Bluetooth™ wireless technologies. Thus, the communication can be a predefined structure as with a conventional network or simply an ad hoc communication between at least two devices. [0100] Wi-Fi, or Wireless Fidelity, allows connection to the Internet from a couch at home, a bed in a hotel room, or a conference room at work, without wires. Wi-Fi is a wireless technology similar to that used in a cell phone that enables such devices, e.g., computers, to send and receive data indoors and out; anywhere within the range of a base station. Wi-Fi networks use radio technologies called IEEE 802.11 (a, b, g, etc.) to provide secure, reliable, fast wireless connectivity. A Wi-Fi network can be used to connect computers to each other, to the Internet, and to wired networks (which use IEEE 802.3 or Ethernet). Wi-Fi networks operate in the unlicensed 2.4 and 5 GHz radio bands, at an 11 Mbps (802.11a) or 54 Mbps (802.11b) data rate, for example, or with products that contain both bands (dual band), so the networks can provide real-world performance similar to the basic 10BaseT wired Ethernet networks used in many offices. [0101] The above description of illustrated embodiments of the subject disclosure, including what is described in the Abstract, is not intended to be exhaustive or to limit the disclosed embodiments to the precise forms disclosed. While specific embodiments and examples are described herein for illustrative purposes, various modifications are possible that are considered within the scope of such embodiments and examples, as those skilled in the relevant art can recognize. [0102] In this regard, while the subject matter has been described herein in connection with various embodiments and corresponding FIGs, where applicable, it is to be understood that other similar embodiments can be used or modifications and additions can be made to the described embodiments for performing the same, similar, alternative, or substitute function of the disclosed subject matter without deviating therefrom. Therefore, the disclosed subject matter should not be limited to any single embodiment described herein, but rather should be construed in breadth and scope in accordance with the appended claims below.

A network device can be placed in a central location to detect and disseminate mobile device data via a wireless network. The network device actions can be determined by an end-user device that receives subscription-based data. The end-user can determine parameters for communication between the network, network device, and the mobile device and determine actions based on the communication.

BACKGROUND [0001] The present invention relates to a tool device, and more particularly to a driver including a driving shaft rotatably attached to a handle. More particularly, the invention relates to a driver with a shaft that is either rotatable relative to the handle to a straight position in line with the handle to form a typical screw driving tool, or rotatable relative to the handle to a perpendicular position relative to the handle to form a T-shaped driving tool for allowing the tool device to be worked in different working positions. [0002] It is well known in the prior art to provide a screwdriver in which a driving shaft is rotatable relative to a handle for facilitating a user to apply additional drive torque to the screwdriver. However, a shortcoming in prior art drivers of this type is that the connection between the driving shaft and the handle is typically flimsy and unstable. Specifically, the mechanism provided in the prior art for holding the driving shaft in a fixed alignment with the handle is typically flimsy, and may allow the alignment of the shaft to suddenly become released or disconnected from its position, and rotate to another position. This can have severely disadvantageous results, in which the user may be injured, or the work piece being worked upon may become damaged. [0003] Thus there is a need in the art for a driver tool that overcomes these shortcomings. The present invention addresses these and other disadvantages. SUMMARY OF THE INVENTION [0004] In a preferred embodiment, the present invention includes a screwdriver that is movable from a first position to a second position. In the first position, the drive shank of the screwdriver is positioned parallel with the elongate handle. In the second position, the drive shank of the screwdriver is positioned perpendicular to the elongate handle, and is selected when additional torque must be applied to the drive shank. [0005] The preferred embodiment comprises an elongate handle, the handle defining a handle slot extending along the handle, the handle further defining a parallel stub hole and a perpendicular stub hole. A pin passes through the handle slot, the pin extending perpendicular to the handle. A drive shank is located partially in the handle slot, the shank defining an elongate shank slot, and further defining a stub at a terminal end of the shank, the stub being sized to fit snugly within the parallel stub hole and, separately, to fit snugly within the perpendicular stub hole, wherein, the pin extends through the shank slot such that the shank is configured to rotate about the pin and also to slide longitudinally in relation to the pin. Arising from this structure, the shank is configured to be moved, electively, to a first position extending parallel with the handle such that the stub is snugly positioned within the parallel stub hole, and, electively, to a second position extending perpendicular to the handle such that the stub is snugly positioned within the perpendicular stub hole. In another aspect of the invention, the screwdriver further comprises a spring positioned between the pin and the shank, the pin being configured to bias the shank away from the pin. In a preferred aspect, the shank comprises a drive shaft that defines the screw driver tip at a distal end: and further comprises a holder that defines the shank slot and defines the stub, and also defines a cylindrical opening configured to receive the drive shaft. [0006] These and other advantages of the invention will become more apparent from the following detailed description thereof and the accompanying exemplary drawings. BRIEF DESCRIPTION OF THE DRAWINGS [0007] FIG. 1 is a front view of a screwdriver, in a first position, showing features of the present invention. [0008] FIG. 2 is a front view of the screwdriver of FIG. 1 , shown in a second position. [0009] FIG. 3 is a front sectional view of a screwdriver in a first position as seen in FIG. 1 . [0010] FIG. 4 is a front sectional view of a screwdriver in a position intermediate the first position as seen in FIG. 1 and the second position as shown in FIG. 2 . [0011] FIG. 5 is a front sectional view of a screwdriver in a second position, as shown in FIG. 2 . [0012] FIG. 6 is a side sectional view taken substantially through line 6 - 6 in FIG. 3 . [0013] FIG. 7 is a side sectional view taken substantially through line 7 - 7 in FIG. 3 . DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS [0014] With reference to the figures, a detailed description of the preferred embodiment of the present invention is described showing a screwdriver having features of the present invention. The screwdriver 10 of the preferred embodiment has a handle 12 for applying torque to a drive shaft 14 . The drive shaft 14 may extend between two positions in relation to the handle, namely a first position shown in FIG. 1 , and a second position shown in FIG. 2 . In the first position, the shaft 14 extends parallel with the longitudinal axis of the handle 12 , and provides the shape of a regular screwdriver. In the second position, the shaft 14 extends perpendicular with the longitudinal axis of the handle 12 to provide a T-shaped connection which is useful for tasks requiring a large amount of torque to be transmitted via the shaft. [0015] In order to support the novel features of the invention, a pin 18 is provided to extend through the handle 12 . A holder 20 is positioned within the handle, is configured to rotate about the pin 18 , and also to receive and capture the drive shaft 14 . Importantly, the holder defines an elongate slot 24 which extends longitudinally along the holder. At a first end of the holder is a male stub 21 sized to mate with two female stub holes inside the handle. As used herein, the shaft 14 and the holder 20 are together referred to as a “shank” or “drive shank.” The pin 18 passes through the holder slot 24 to secure the holder 20 from falling out of the handle. The configuration of the holder in relation to the handle 12 and the shaft 14 permits the holder 20 two degrees of freedom. First, the holder (with shaft held in the holder) can rotate about the pin 18 thereby allowing the shaft to rotate from the first position ( FIG. 1 ) to the second position ( FIG. 2 ). To facilitate this rotational movement, a handle slot 16 is provided in the handle that is configured to allow the holder and shaft to pass through the handle (via the handle slot 16 ) between first and second positions. Second, the holder (with shaft held in the holder) can slide along the longitudinal axis of the holder in relation to the pin 18 . This sliding motion will be described in further detail below, but it may be seen with reference to FIGS. 4 and 5 in which FIG. 4 shows the holder (and shaft) slid longitudinally upward in relation to the pin, and FIG. 5 shows the holder (and shaft) slid longitudinally downward in relation to the pin. [0016] Additional components of the preferred embodiment include a spring 22 (preferably a helical spring) which is positioned inside the holder 20 to abut against the pin 18 , and is configured to provide a force on the holder that biases the holder away from the pin and into the handle, in both the first and second positions. Further features of the preferred embodiment include a parallel stub hole 28 and a perpendicular stub hole 26 . These two stub holes are sized to snugly receive the stub 21 of the holder, and thus to provide a detent feature between the stub 21 and the stub holes 26 , 28 . [0017] Thus, in the first position as seen in FIGS. 1 and 3 , the holder 20 is biased into the handle 12 by the spring 22 so that the stub 21 is biased towards and fits snugly into the parallel stub hole 28 . Thus, the holder 20 is provided with resistance against rotation in relation to the handle by a couple provided a contact between the stub 21 and parallel stub hole 28 , and contact between the pin 18 and holder slot 24 . These two contact points along the shank separated from each other by a lever arm of about one half to one inch, and prevent the shaft from rotating away from the first position in relation to the handle during use. [0018] In the second position as seen in FIGS. 2 and 5 , the holder is biased across the handle 12 by the spring 22 so that the stub 21 is biased towards and fits snugly into the perpendicular stub hole 26 . Thus, the holder 20 is provided with resistance against rotation in relation to the handle by a couple provided by a contact between the stub 21 and perpendicular stub hole 26 , and contact between the pin and holder slot. These two contact points are likewise separated from each other by a lever arm of about one half to one inch, and prevent the shaft from rotating away from the second position in relation to the handle during use. [0019] Furthermore, when the stub 21 of the holder 20 is positioned in one of the stub holes 26 , 28 , the holder is provided with a bias by the spring 22 against popping out of either stub hole, thereby ensuring an advantageously safe working condition. [0020] In use, the screwdriver of the present invention is configured to operate as follows. Taking the screwdriver in its first position ( FIGS. 1 and 3 ) the user may apply torque to a work piece (not shown). If the user determines that he requires greater torque than he can generate with the screwdriver in the first position, he pulls the shank (i.e. the shaft 14 along with the holder 20 ) longitudinally out of the handle against the bias of the spring 22 so that the spring 22 becomes compressed against the pin 18 . He then rotates the shaft in relation to the handle by passing it through the handle slot 16 until it reaches a position that is perpendicular to the handle, as exemplified in FIG. 4 . It will be seen in FIG. 4 that the spring 22 is still in the compressed condition. The user then either lets go of the shank thereby allowing the spring 22 to push the shaft into the handle, and thus allowing the pin 18 to slide within and relative to the holder slot 24 so that the stub 21 of the holder 20 snugly enters the perpendicular stub hole 26 where it is held securely with a détente action. In this second position, the shaft 14 is held securely against rotation in relation to the handle 12 , and the user may apply the required degree of torque to the work piece (not shown.). [0021] Once this application of torque is complete, and in reverse, the user may then pull the shaft from its second position ( FIG. 5 ) against the bias of the spring 22 , to compress the spring 18 , and withdraw the stub 21 from the perpendicular stub hole 26 (as seen FIG. 4 ). The user then rotates the shaft to align the shaft with the handle (by passing the shaft through the handle slot 16 ), and then allows the spring 22 to bias the shaft into the handle so that the stub 21 snugly enters the parallel stub hole 28 to secure the shaft and holder in the first position, as seen in FIG. 3 . Naturally, in either case, the user may assist the spring 22 bias by pushing the shank with his hand in the desired assisting direction, either horizontally or perpendicularly. [0022] The resulting structure provides a stable couple to hold the shank in both the first and second positions, and allows a user to easily adjust the shank from the first to the second positions by merely pulling the shank out of its first restrained position, rotating the shank, and inserting the shank into a second restrained position that is perpendicular to the first, and then to reverse the process when desired. The large restraining couple lever arm allows for stabilizing forces internal to the handle of the screwdriver that are much smaller than forces that are generated in mechanisms of the prior art configured to hold a shank in a stable position against rotation. With smaller restraining forces in the present invention, the handle and its restraining mechanism have a prospect of a longer user life than screwdrivers in the prior art that are configured to adjust between two perpendicular positions. [0023] Thus, there has been described a configuration for a screwdriver that overcomes shortcomings in the prior art. The present invention may, of course, be carried out in other specific ways than those herein set forth without departing from the essential characteristics of the invention, which is set forth in the claims below.

The application discloses a screwdriver that is movable from a first position to a second position. In the first position, the drive shank of the screwdriver is positioned parallel with the elongate handle. In the second position, the drive shank of the screwdriver is positioned perpendicular to the elongate handle, and is selected when additional torque must be applied to the drive shank. Structure of the screwdriver provides enhanced stability for the drive shank supported by the handle.

CROSS-REFERENCE TO RELATED APPLICATIONS [0001] This application is based upon and claims the benefit of priority to provisional U.S. Application No. 62/092,570, filed Dec. 16, 2014, the entire contents of which are incorporated herein by reference. BACKGROUND [0002] 1. Field of Disclosure [0003] Embodiments described herein generally relate to a framework for randomizing instruction sets, memory registers, and pointers of a computing system. [0004] 2. Description of Related Art [0005] The background description provided herein is for the purpose of generally presenting the context of the disclosure. Work of the presently named inventors, to the extent the work is described in this background section, as well as aspects of the description that may not otherwise qualify as prior art at the time of filing, are neither expressly nor impliedly admitted as prior art against the present disclosure. [0006] Instruction sets, memory registers, and pointers that are used in most computing systems are fairly standardized. Standardized machine instruction sets provide consistent interfaces between software and hardware, but they are a double-edged sword. Although they yield great productivity gains by enabling independent development of hardware and software, the ubiquity of well-known instructions sets also allows a single attack designed around an exploitable software flaw to gain control of thousands or millions of systems. Accordingly, having a standardized instruction set facilitates intellectual property theft, computer exploitation, hacking and the like. [0007] Address space layout randomization (ASLR) is a memory-protection process for operating systems (OSes) that guard against buffer-overflow attacks by randomizing the location where system executables are loaded into memory. While ASLR is a practice to randomize instruction addresses in library code, and is a form of ontology encoding that thwarts library injection code attacks, ASLR does not address the challenges faced by a cloud application that is based on binary code static instruction addresses. [0008] Accordingly, a technique is required to address the above stated deficiencies in the art and to further provide software protection such that code cannot be decrypted or attacked by side-channels. SUMMARY [0009] Computer systems utilize standardized instruction sets and, to a lesser extent, memory registers and pointers, regardless of the chip sets used. Such an industry standard help promote software development. An aspect of the present disclosure provides for the randomization of instruction sets, memory registers, and pointers thereby providing security against reverse engineering, side-channel intercept and analysis, and other methods of data analysis. An aspect of the present disclosure provides for randomizing instruction sets, memory registers and pointers without requiring changes in software development, neither in chip set design nor manufacturing. Accordingly, the security techniques described herein overcome technological limitations in both randomization and key index management. [0010] An aspect of the present disclosure provides for a method and apparatus for software protection such that software code cannot be decrypted or attacked by side-channels. Furthermore, by one embodiment, the present disclosure overcomes the limitations associated with standardized instruction sets, memory registers and pointers by introducing a notion of randomness in their respective generations. Furthermore the present disclosure provides an improvement over typical run-time per call dispatch decryption, wherein typically the body of the code remains encrypted in that it leverages, among other things, new discoveries in the field of Full Ontological Encryption (FOE), artificial intelligence, machine learning, networks of semi-autonomous agents, Self-Modifying Instruction Randomization Code (SMIRC), and Semantic Dictionary Encryption (SDE). [0011] The foregoing paragraphs have been provided by way of general introduction, and are not intended to limit the scope of the following claims. The described embodiments, together with further advantages, will be best understood by reference to the following detailed description taken in conjunction with the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS [0012] A more complete appreciation of the disclosure and many of the attendant advantages thereof will be readily obtained as the same becomes better understood by reference to the following detailed description when considered in connection with the accompanying drawings, wherein: [0013] FIG. 1 illustrates according to one embodiment, an exemplary hierarchy of processes; [0014] FIG. 2 illustrates an example depicting the randomization performed by a processor; [0015] FIG. 3 illustrates one embodiment of the framework according the invention; [0016] FIG. 4 illustrates one embodiment of the process according to the invention; and [0017] FIG. 5 illustrates a block diagram of a computing device according to one embodiment. DETAILED DESCRIPTION OF EMBODIMENTS [0018] Referring now to the drawings, wherein like reference numerals designate identical or corresponding parts throughout the several views. Accordingly, the foregoing discussion discloses and describes merely exemplary embodiments of the present disclosure. As will be understood by those skilled in the art, the present disclosure may be embodied in other specific forms without departing from the spirit or essential characteristics thereof. Accordingly, the present disclosure is intended to be illustrative, but not limiting of the scope of the invention, as well as other claims. The disclosure, including any readily discernible variants of the teachings herein, defines, in part, the scope of the foregoing claim terminology such that no inventive subject matter is dedicated to the public. [0019] Turning to FIG. 1 is depicted an exemplary interlocking set of processors. By one embodiment, an application program can be divided into various jobs, referred to herein as sub-routines or tasks. Each of the tasks can be distributed by a master processor to a subordinate processor. The subordinate processor thereafter may elect to become its own master processor, and further subdivide the task assigned to it into various sub-tasks and assign each of the sub-tasks to its subordinate processors. Thus, in this manner, the program may be divided into many different tasks, with each task assigned to a subordinate processor. It must be appreciated that each subordinate processor is a master processor with regard to the processors to whom the subordinate processor assigns tasks. Thus, the execution of the program may be considered to be performed by a hierarchy of processors as shown in FIG. 1 . [0020] Grammars are used to describe sentence structures based on a set of rules, which depend on the type of grammar being implemented. For instance, a context-free grammar (CFG) is a set of recursive rewriting rules (or productions) that are used to generate patterns of strings. A CFG includes the following components: a set of terminal symbols, which are the characters of the alphabet that appear in the strings generated by the grammar; a set of nonterminal symbols, which are placeholders for patterns of terminal symbols that can be generated by the nonterminal symbols; a set of productions, which are rules for replacing (or rewriting) nonterminal symbols (on the left side of the production) in a string with other nonterminal or terminal symbols (on the right side of the production); and a start symbol, which is a special nonterminal symbol that appears in the initial string generated by the grammar. [0021] By one embodiment of the present disclosure, a master processor creates a hierarchy of processors that execute an application program. Specifically, as stated previously, a master processor creates a random number of sub-processes. Each sub-processor in turn, may act as a master processor and create its own sub-processes. Each of the sub-processors is assigned a unique random instruction set, memory registers and pointers by its master processor. By one embodiment, grammars may be used to determine a randomized instruction set, memory registers and pointers for each sub-processor. In doing so, the present disclosure incurs the advantageous ability of providing a security mechanism against potential exploitation threats to the program. [0022] Accordingly, the attempts by malicious software programs or reverse engineering techniques made to exploit the vulnerabilities of the program are prevented. Specifically, due to the number of processors that are used to execute the program are random, and the instruction set assigned to each processor is determined in a random manner (based on the Grammar), current and future reverse engineering programs have no mechanism of acquiring the translation table for the instruction set, or the locations of pointers and memory registers. [0023] Furthermore, as an added layer of security, each time the application is turned on, a new translation table is provided by a higher-layer processor and attempts to compromise the processor fail because the various running applications within the processor will not adhere to standardized instruction sets, memory registers or pointers. Thus, by one embodiment, the number of processors used will be random and as such the reverse engineer or malicious software will not know how many times it must attempt to break out of each processor, and the attempt to break out of the processor will cause the supervising processor to shut down the sub-processor and reboot it, with an entirely new randomized instruction set, memory registers and pointers. [0024] By one embodiment of the present disclosure, Van Wijngaarden (VW) grammar is used to create a random instruction set, memory registers, and pointers that are assigned to each sub-processor. VW grammar can be visualized as a composition of two context-free grammars (i.e., the VW is a two-level grammar). The first context-free grammar is used to generate a set of terminal symbols which acts as non-terminals for the second context-free grammar. [0025] Ontology encryption is a cypher system that obscures the content of data in such a way that operations can be performed on specific elements of the data without revealing the contents of those elements. Homomorphic encryption techniques rely on homomorphsims, which can be defined as a data map which preserves structure of data groups, in other words it shifts data relative to a single grammar. In contrast, ontology encryption is different as it shifts data relative to multiple grammars. Specifically, by one embodiment of the present disclosure, data may be shifted within a single grammar, within a two-layer grammar (VW grammar) and/or within M of N grammars. M of N grammars can be parallel, serial, or cascading. Accordingly, ontology encryption can occur by using many methods and embodiments of the present disclosure can incorporate and leverage all forms of ontology encryption. [0026] FIG. 1 depicts a non-limiting example illustrating a hierarchy of processors 100 . As shown in FIG. 1 , an application program 101 is executed in a hierarchy of three levels of processors. The hierarchical series of processors 100 includes a master processor 110 that controls sub-processors 121 , 122 , and 123 . Each processor is allocated a randomized instruction set, memory pointers, and registers that enable securing, data, instruction set, memory pointers and registers from an adversary attempting to reverse engineer, understand, or cause the processor to perform unauthorized procedures or assist the adversary in a manner the adversary chooses. [0027] As shown in FIG. 1 , the master processor 110 implements a master randomization process 131 (i.e., creating a grammar) to generate a translation table 141 (translation table of instruction sets) that assigns a randomized instruction set, memory registers and pointers to the first sub-processor 121 . In a similar manner, the sub-processor 121 may act as its own master processor and assign a portion or all of the tasks assigned to it by the master processor 110 , to a second sub-processor 122 . In doing so, the sub-processor 121 also allocates a randomized instruction set, memory registers, and pointers (by implementing sub-randomization process 132 ) to generate a translation table 142 for the second sub-processor 122 . [0028] Furthermore, the second sub-processor 122 may implement a sub-randomization process (i.e., creating grammar based on VW grammar) to assign a randomized instruction set, memory registers, and pointers to a third sub-processor 123 , via the third translation table 143 . Moreover, it must be appreciated that although the illustration as depicted in FIG. 1 includes only three levels (iterations) of sub-processor creation, the techniques described herein are applicable to any number of hierarchical processors. [0029] In FIG. 1 , each sub-processor is provided a randomized instruction set, memory register, and pointers by its managing processor that controls it. For instance, instead of being required to add X+Y, the sub-processor would be tasked with adding Z mod X with A mod Y. It is the task of the controlling processor (i.e., the managing processor/master processor of the sub-processor) to know the true algorithm, and when provided with an answer (by the sub-processor) to apply the algorithm (translation) to derive the correct solution. Thus, in this manner, each processor will process only portions of the program, and each of those portions of the program will have gone through several obfuscation steps. Additionally, by one embodiment, each time the corresponding portion of the program is run, it may be executed on a different processor, in a different virtual machine. Specifically, due to the randomness in determining the number of processors to use in execution of a particular program, each portion of the program may be executed on different processors during each execution iteration of the application. [0030] In this manner, an adversary will be challenged to know the exact data that is being processed at a particular time instant, and also where the full program resides. Furthermore, the adversary will not know where the unencrypted data resides (instruction set, memory pointer, or register) or even the layer of obfuscation that the adversary is examining at that moment, or at which layer does the master processor create the master translation table and stores the method of key management and randomization for the processors immediately under its control. [0031] Furthermore, as each processor activates a sub-processor under its temporary control, the processor injects randomization into the controlled processes and retains a generated master index for the processor. Accordingly, the overall program is more fully protected. The sub-processors controlled by the master processor are themselves in control of yet other sub-processors underneath them and act as master processors for those sub-processors. Thus, the program expands and retracts in a random manner with each expansion being assigned to a newly appointed master control processor. In this manner, the program maintains state, yet its location in the computer system is known only by itself and each part of it is contained in a protected stub state as the program expands throughout the computer system only to retract again, reformulate, assign a new master controller processor and repeat an expansion cycle. [0032] An advantageous ability incurred in performing the randomization of the number of processors as well as randomizing the instruction sets, memory registers, and pointers is that a malicious software or reverse engineer would only be able to determine that the command being executed at a particular time instant is, for example, 2+2. An adversary seeing this command would not know if the number 2 is an encrypted and randomized number, if the addition instruction is indeed a true instruction, and neither would the adversary know which processor in the computer system is the current master control, sub-processor and the like. [0033] Finally, the adversary would not know as to why this instruction set is being executed at a particular time instant. As the adversary attempts to compromise and analyze each processor in the computer system, the adversary will still not know how many processors are actually in the computer system, because the number of processors themselves is randomly chosen. Furthermore, by one embodiment, a random number of additional processors are introduced in order to create noise, which appears to be valid processing but is disregarded by the program. [0034] Additionally, but the malicious software or reverse engineer would not know what the command 2+2 designates, as it has been translated by the master processor. Furthermore, the next time that command is run, it might appear as ⅚ , as the master processor (of a particular sub-processor) randomizes the instruction set at each cycle of execution. [0035] It must be appreciated that embodiments described herein are not limited to a single computer system but is also applicable to a networked computer system having distributed storage, and processing computer systems, and the like. Additionally, the above described embodiments are equally applicable to a distributed processing and storage systems, referred to as ‘the cloud network’. [0036] Moreover, whether leveraging distributed processing and storage systems, the process of the above described embodiments is still applicable, i.e., a random number of processors is chosen by the master processor and assigned to the temporary cluster of processors needed for the task. Such an M of N structure (i.e., random number of processors, each with a random number of processing cycles) further obfuscates the processes and data such that an adversary will not know how many processors he or she must examine to fully analyze the process and data. The master processor may assign tasks to each layer-1 processor, which in turn may create additional layers underneath it and act as a sub-master processor. Such a process continues until the cluster of processors is instructed to reconfigure itself with a new master processor and new layers. [0037] Turning now to FIG. 2 is illustrated a non-limiting example depicting the randomization process described in the above embodiments. FIG. 2 depicts an instance of a program loader 210 coupled to processor/virtual machine 220 and a bytecode file 230 that corresponds to a computer object code. The processing performed on the bytecode file 230 by a randomization process of the present disclosure is depicted in 240 . [0038] The loader 210 is a component that locates a given program (which can be an application or, in some cases, part of the operating system of the computer itself) in an offline storage (such as a hard disk), and loads it into a main storage (e.g., random access memory in a personal computer) for execution. [0039] Further, the bytecode file 230 includes a computer object code that is processed by a program (e.g., a virtual machine). As shown in FIG. 2 , the bytecode file includes a header and a sequence of indexes 250 for the instructions. For each index (corresponding to an instruction), by one embodiment of the present disclosure, a special key 260 (i.e., an opcode) is generated in a random manner. Note that the opcode generated for an instruction specifies an operation to be performed. Accordingly, by randomly generating an opcode for the instruction set, provisions the present disclosure to prevent malicious software or reverse engineers to track the exact execution of the application. In other words, the bytecode file is encrypted (in a random manner at run time) such that when the file is decrypted the runtime processing is rearranged. [0040] By one embodiment of the present disclosure, the steps that each processor undertakes in the randomization process are as follows: 1) the binary code is transformed into an Self-Modifying-Instruction-Randomization-Code (SMIRC) and Semantic Dictionary Encryption (SDE) (i.e., a SMIRC+SDE) representation, 2) the SMIRC+SDE representation is further transformed into a Van Wijngaarden Grammar Synthesizer (VWGS), that generates via a write-back process a generator stub (block of instructions) the which creates a small binary executable. Note that the stub is protected via run-time per-call dispatch decryption while the body of code remains encrypted. The process may further regenerate the original application in binary form. Accordingly, a full ontology encryption is employed by the embodiments described herein via run-time randomization, at random times, of the binary using ontological encryption generated from the stub. Cryptographic Protocol [0041] The processing system (for example a virtual machine (VM)) is composed of two parts: an Outer Processing System (OPS) OPS host running on the real cpu hardware, and an inner, guest part running in an Inner Processing System (IPS) such as in a virtualized virtual machine container (i.e. like qemu). All information about the real identity of the user and the user's process (i.e computer) is maintained by the OPS. All application subroutines are run from the IPS. Writable access control is solely permitted by the IPS as a subordinate processor such as a virtual device provided by the OPS. Encryption runs on the OPS such that the inner machine does not have access to the key. [0042] In this way the OPS functions as a Master Processor and the IPS functions as a Subordinate Processor (which can also function as a Master Processor for its own Subordinate Processors). The OPS, (for example an IPSOPS virtual machine image) is part of a host VM that houses the IPS (for example an inner OPS VM), so that each instance of an OPS appears identical in every way that can be seen from inside (i.e. user name, mac addresses, and IP addresses). The interface presented to the inner machine by the outer machine is always the same also; for example, the inner machine always refers to the outer machine using the same names. [0043] The outer machine runs from a hypervisor, and all code that has to talk to the “real” network. The inner machine can only connect only to the allocated cryptographic port of the outer machine. The outer machine has a firewall configured such that no traffic can ever be relayed directly from the inner machine to the network. The only way the inner machine can talk to another processor should be through the port allocated by the outer machine. [0044] There are two types of cryptography: [0045] 1. symmetric cryptography (such as RC4, RC5, SHA-1 and MD5) and [0046] 2. asymmetric cryptography (such as RSA and ECC). [0047] The OPS creates the SMIRC+SDE via cryptography mechanisms, as shown in FIG. 4 . In this example the symmetric RC5 algorithm is used however any symmetric encryption algorithm may be used and adopted for communication between application subroutines (i.e. these are co-routines or resource constrained nodes running as a component of the master application). An asymmetric cryptography (such as the RSA algorithm), is applied for communication between OPS and IPS. [0048] The two protection mechanisms execute within trusted emulators while remaining out-of-band of untrusted systems (i.e. the systems that are being emulated). The integrity and reliability of the system depends upon keeping attackers in sandboxes within the emulated environments. The OPS) and IPS) interact using the following rules: [0049] 1. OPS copies IPS instructions from IPS memory into OPS memory. [0050] 2. IPS instructions are translated to a set of OPS instructions. When this set of translated OPS instructions execute the state of IPS memory and registers is modified such that it appears as if the original IPS instructions had been executed. [0051] 3. The translation process ensures IPS instructions read and write IPS memory exclusively. The OPS memory is inaccessible by IPS instructions and the translated set of OPS instructions cannot read or write OPS memory. As a result, the set of translated instructions will never be self-reading. The IPS instructions sandbox is the restricted memory space. [0052] End-to-end encryption is impractical because of large number of communicating nodes in a Cloud framework because of the need to manage, store and recall large numbers of encryption keys. In the present method, we assume the number of computation nodes is N, we allocate the OPS to perform a hop-by-hop encryption with IPS nodes, in which each IPS subnode stores encryption keys shared with its immediate neighbors. Keys stored in OPS nodes include the keys shared with its neighbors and the IPS node which has keys shared with its subnodes and one key with the OPS. This method minimizes memory required for keys as well as the power consumption of transmitting keys. Method Protocol [0053] 1. OPS clones encrypted IPS SMIRC+SDE instructions into OPS memory. The encrypted IPS decrypt in OPS memory. These instructions remain, therefore, out-of-band of the IPS and are not accessible by the IPS. [0054] 2. Decrypted IPS SMIRC+SDE instructions are translated (or interpreted) to a set of OPS instructions using a Van Wijngaarden grammar specified as a simple two-layer translator (see FIG. 4 ) of the target IPS. [0055] 3. The set of translated OPS instructions execute the state of the IPS and such that it appears as if the original IPS instructions had been executed. The translation process ensures IPS instructions never read decrypted IPS instructions. [0056] 4. The encrypted instructions are decrypted in OPS memory using OPS routines. The emulation sandbox ensures OPS memory is inaccessible by the IPS (i.e. decrypted instructions and decryption routines are out-of-band). The encrypted IPS executable does not have any decryption process and does not see the key needed to decrypt the instructions: decryption always stays out-of-band. [0057] 5. The translation mechanism of the OPS will re-write the instructions it has executed using the two level grammar into the IPS, which means the IPS never has the same image twice in a row and therefore the attack surface will never be the same twice. Method: Key-CodeHash Pairing Whitelist [0058] The encryption key itself is associated, using a simple hashmap to a hash (for example an MD5) of the subroutine or IPS code as the IPS code reciprocally has the OPS hash: this encoding defines an execution model that executes only paired signed OPS with IPS and IPS with its subnodes: therefore, unpaired unsigned malicious code such as rootkits and exploits will never be executed the principal reason is that the hash (example MD5) has to be recomputed each time a new translation is completed and this provides tamper evidence as well as tamper resistance. Van Wijngaarden (VW) Grammar Rules [0059] VW grammars are context-sensitive and therefore, for those skilled in art, can be used to write rules which transform one form of code (of, for example, an x86 instruction set) into another form while preserving its semantics which is its context's information. VW can define a long-range relation: this means that information flows contextually through the sentential form of the representation of the code (e.g. x86 assembler). When the VW is used in the context of the OPS and IPS then information must flow to the subnodes which look at their neighbors to rewrite one code form into another. Thus, using the VW grammar as a code translation engine implies that it requires almost all rules to know something about almost all the other rules which makes the attack surface very difficult. The First Level Translator Grammar [0060] The first level grammar generates the computer code. As a concrete example, the first level grammar for the x86 instruction set can be given using symbols S, T, U and V as: [0061] S -> mov eax, key T [0062] T -> xor [ ebx], eax U [0063] U -> inc ebx V [0000] This first level grammar generates the following executable instruction codes: [0064] mov eax, key [0065] xor [ ebx], eax [0066] inc ebx [0067] The codes are generated by the sequence of non-terminal symbols S -> T -> U -> V. Specifically, a non-terminal such as S can be rewritten as “mov eax, key T”, which can be again rewritten as “mov eax, key xor [ebx], eax U”, etc . . . . The production rules defined can generate an equivalent sequence of instructions for arbitrary programs: [0068] S -> mov eax, key T | push key; pop eax T [0069] T -> xor [ebx], eax U | mov ecx, [ebx]; [0070] and ecx, eax; not ecx; or [ebx], eax; [0071] and [ ebx], ecx U [0072] U -> inc ebx V | add ebx, 1 V [0073] Similarly, code without any functional effect can be added to vary the IPS by the OPS. This can be done by adding a new non-terminal which generates “non-operational sequences” instructions with small overheads such as: S -> G mov eax, key T | G push key; pop eax T [0074] These increase the number of instruction sequences that can be generated to increase the variance in the IPS and subnodes. The Second-Level Translator Grammar [0075] In the present patent, the method used is a random generator during the production process, to enable the production to randomly generate semantic and context preserving code sequences using the following VW metarules (to distinguish between metarules, the hyperrules, and the production rules, we change the usual Backus-Naur syntax ‘-> ’into ‘;’ and :: for metarules and colon (‘:’) for hyperrules. To separate the different alternatives of a rule we use semi-colon ‘;’ instead of ‘|’): [0076] N :: 0; 1; 2; . . . ; 9; 0N; . . . 9N; [0077] HEXIDECIMAL :: N; a; b; f; a HEXIDECIMAL; b HEXIDECIMAL; . . . ; f HEXIDECIMAL. [0078] ADDRESS :: 0xN. [0079] NUMBER :: MEMORY ADDRESS; HEXIDECIMAL. [0080] INSTRUCTION :: mov; push; pop. [0081] MEMORY REGISTER :: eax; ebx; edx. [0082] STACK :: esp. [0083] MEMORY REGISTERS :: STACK; REGISTER. [0084] REGISTER NUMBER :: REGISTER; NUMBER. [0085] MEMORY :: [ REGISTER]; [ ADDRESS]. [0086] TO :: ‘,’. [0087] In the following table we demonstrate in lay terms how Ontological Encryption functions independent of chip architecture because it is done at a binary level. [0000] Ontologically Actual Ontologically Encrypted Instruction Original Binary Encrypted Binary Instruction Add 2 to 2 01000001 01100100 01110011 01110101 Subtract 3 from 3 01100100 00100000 01100010 01110100 00110010 00100000 01110010 01100001 01110100 01101111 01100011 01110100 00100000 00110010 00100000 00110011 00100000 01100110 01110010 01101111 01101101 00100000 00110011 Compare 01100011 01101111 01101101 01101111 Move 3 to 2 eax to ebx 01101101 01110000 01110110 01100101 01100001 01110010 00100000 00110011 01100101 00100000 00100000 01110100 01100101 01100001 01101111 00100000 01111000 00100000 00110010 01110100 01101111 00100000 01100101 01100010 01111000 [0088] The metanotion NUM represents an address or a hexadecimal number while INSTRUCTION represents several instructions, not just a single instruction (e.g. mov, push and pop). The following translations will modify an instruction into a readable and rewritable sentence that can be executed as equivalent to its subroutine given by the following hyperrules: [0089] mov REGISTERS TO REGISTER NUMBER : [0090] move REGISTER NUMBER in REGISTERS. [0091] push REGISTER NUMBER : [0092] save REGISTER NUMBER. [0093] pop REGISTERS : [0094] restore REGISTERS. [0095] As a concrete example of a short subroutine, the codes “mov eax, 0” will be replaced by “move 0 in eax”, because of the first hyperrule. To generate even higher complexity, we can add hyperrules which will transform codes into other equivalent codes: [0096] move REGSTER NUMBER in MEMORY : [0097] mov, MEMORY, TO, REGISTER NUMBER; [0098] move REGISTER NUMBER in REGISTERS : [0099] mov, REGISTERS, TO, REGISTER NUMBER; [0100] save REGISTER NUMBER, restore REGISTERS. [0101] For example, the codes obtained before (“move 0 in eax”) can be revised into “mov, eax, ‘,’, 0” or by “save 0, restore eax”. The first alternative will halt the generation process. However, the codes “mov”, “eax”, “‘,’ ” and “0”, where none of them match a left-hand side of a hyperrule will halt. However, other alternatives will continue generation, and both parts of the code, “save 0” and “restore eax”, will be replaced independently from each other. Therefore, “save 0” can be replaced by “push, 0 ” or by “subtract 4 from esp, move 0 in [ esp]”, etc. The metarules defined above can be more extended by creating tables of equivalent instruction grammars for different processors (e.g. ARM, Intel, or other hardware) because they are performed through binary translation which means that the invention is not restricted to just one binary instruction chip architecture but may be used by any chip architecture (ARM, Intel or other hardware). The VW grammars can generate an infinite set of instructions for variability and so the hyperrules generate an infinite number of production rules: in practice, the amount is limited by setting a fixed counter on a per IPS basis to ensure diversity but also minimizing overheads of runtime. We call each of the VW generated target code sequences a “Stub”. [0102] The various subroutines of an IPS can each be defined by a separate VW grammar. Starting symbols of the grammar are themselves starting symbols of a grammar describing each program as a construction of stubs. The VW grammar produces a constructive method to generate those codes of the target machine CPU automatically. The OPS provides the whole operational program but the OPS itself can be redefined by the same process of the IPS. Thus a Van Wijngaarden grammar can be used to define IPS from the starting OPS which produces all the parts of the IPS, then the OPS can itself be translated via a runtime cloning or copying process: As an example, for a OPS with 4-level VW grammar definition where the parent, OPS, rewrites ongoingly is: [0103] OPS : IPS-STUB01, IPS-STUB02, IPS-STUB03, IPS-STUB04 [0104] IPS-STUB01 :VW-Grammar of STUB01 paired and signed to OPS-CHILD [0105] IPS-STUB02 :VW-Grammar of STUB02 paired and signed to OPS-CHILD [0106] IPS-STUB03 :VW-Grammar of STUB03 paired and signed to OPS-CHILD [0107] IPS-STUB04 :VW-Grammar of STUB04 paired and signed to OPS-CHILD [0108] OPS-CHILD : OPS-CHILD paired and signed to OPS [0109] For instance, see Dick Grune, How to produce all sentences from a two-level grammar Information Processing Letters Volume 19, Issue 4, 12 Nov. 1984, Pages 181-185, incorporated herein by reference. Specifically, each stub is assigned to a different processor, for instance, in a cloud environment or some other computer system (described with reference to FIG. 5 ), to be processed and reported back to a supervising processor. In this way, adversaries are challenged to gather the entire code structure, and each time the code runs it will have different instruction sets, memory pointers, registers and data encryption. [0110] FIG. 3 illustrates an example of the processing system including a virtual machine (VM) that is composed of the Outer Processing System (OPS) ( 301 ), and an inner, guest part running in an Inner Processing System (IPS) ( 302 ) as is described above. The OPS 301 includes a meta-data two layer grammar translator. An asymmetric cryptography is applied for communication between OPS 301 and IPS 302 . Furthermore, symmetric cryptography is used for communication between application subroutines. [0111] FIG. 4 illustrates the process for randomizing instruction sets, memory registers, and pointers of a computing system. The execution VM that runs the STUB (to actually run the program) uses the randomly generated codes—in other words, the executing code always appears once, and then the codes leaves while the stack (part of the stub) remains for the next VM to continue the computation. [0112] In step 1, the instructions are encrypted using the OP-Hash in the inner process. In step 2, the encrypted instructions are transmitted to the outer process. In step 3, the instructions are decrypted into the OPS memory and are executed by the VM that runs the STUB. These decrypted instructions remain out-of-band of the IPS and are not accessible by the IPS. The encrypted instructions are decrypted in OPS memory using OPS routines. The emulation sandbox ensures OPS memory is inaccessible by the IPS (i.e. decrypted instructions and decryption routines are out-of-band). The encrypted IPS executable does not have any decryption process and does not see the secret key needed to decrypt the instructions: decryption always stays out-of-band. [0113] In step 4, the decrypted instructions are translated (or interpreted) to a set of OPS instructions using a Van Wijngaarden grammar specified as a simple two-layer translator of the target IPS. The set of translated OPS instructions execute the state of the IPS such that it appears as if the original IPS instructions had been executed. The translation process ensures IPS instructions never read decrypted IPS instructions. [0114] In step 5, the translation mechanism of the OPS re-writes the instructions it has executed using the two level grammar into the IPS. This writing ensures that the IPS never has the same image twice in a row and therefore the attack surface will never be the same twice. [0115] Note the entire process chain shown in FIG. 4 is not required for the system to operate. For instance, although the system goes through all of these steps in one embodiment, in a different embodiment steps may be switched around (reordered) or each and every step may not be required (some steps could be left out). [0116] As stated previously, each of the functions of the above described embodiments may be implemented by one or more processing circuits. A processing circuit includes a programmed processor (for example, processor 503 in FIG. 5 ), as a processor includes circuitry. A processing circuit also includes devices such as an application-specific integrated circuit (ASIC) and conventional circuit components arranged to perform the recited functions. By one embodiment, the circuitry as described in FIG. 5 , can be used to perform the randomization of the instruction sets, memory registers, and pointers to provide the security features described herein. Accordingly, the circuitry upon implementing the randomization process, can provide a secure framework to execute applications thereby improving the overall functionality of the computer. [0117] The various features discussed above may be implemented by a computing device such as a computer system (or programmable logic). The circuitry may be particularly designed or programmed to implement the above described functions and features which improve the processing of the circuitry and allow data to be processed in ways not possible by a human or even a general purpose computer lacking the features of the present embodiments. FIG. 5 illustrates such a computer system 501 . The computer system 501 of FIG. 5 may be a particular, special-purpose machine. In one embodiment, the computer system 501 is a particular, special-purpose machine when the processor 503 is programmed to compute vector contractions. [0118] The computer system 501 includes a disk controller 506 coupled to the bus 502 to control one or more storage devices for storing information and instructions, such as a magnetic hard disk 507 , and a removable media drive 508 (e.g., floppy disk drive, read-only compact disc drive, read/write compact disc drive, compact disc jukebox, tape drive, and removable magneto-optical drive). The storage devices may be added to the computer system 501 using an appropriate device interface (e.g., small computer system interface (SCSI), integrated device electronics (IDE), enhanced-IDE (E-IDE), direct memory access (DMA), or ultra-DMA). [0119] The computer system 501 may also include special purpose logic devices (e.g., application specific integrated circuits (ASICs)) or configurable logic devices (e.g., simple programmable logic devices (SPLDs), complex programmable logic devices (CPLDs), and field programmable gate arrays (FPGAs)). [0120] The computer system 501 may also include a display controller 509 coupled to the bus 502 to control a display 510 , for displaying information to a computer user. The computer system includes input devices, such as a keyboard 511 and a pointing device 512 , for interacting with a computer user and providing information to the processor 503 . The pointing device 512 , for example, may be a mouse, a trackball, a finger for a touch screen sensor, or a pointing stick for communicating direction information and command selections to the processor 503 and for controlling cursor movement on the display 510 . [0121] The processor 503 executes one or more sequences of one or more instructions contained in a memory, such as the main memory 504 . Such instructions may be read into the main memory 504 from another computer readable medium, such as a hard disk 507 or a removable media drive 508 . One or more processors in a multi-processing arrangement may also be employed to execute the sequences of instructions contained in main memory 504 . In alternative embodiments, hard-wired circuitry may be used in place of or in combination with software instructions. Thus, embodiments are not limited to any specific combination of hardware circuitry and software. [0122] As stated above, the computer system 501 includes at least one computer readable medium or memory for holding instructions programmed according to any of the teachings of the present disclosure and for containing data structures, tables, records, or other data described herein. Examples of computer readable media are compact discs, hard disks, floppy disks, tape, magneto-optical disks, PROMs (EPROM, EEPROM, flash EPROM), DRAM, SRAM, SDRAM, or any other magnetic medium, compact discs (e.g., CD-ROM), or any other optical medium, punch cards, paper tape, or other physical medium with patterns of holes. [0123] Stored on any one or on a combination of computer readable media, the present disclosure includes software for controlling the computer system 501 , for driving a device or devices for implementing the invention, and for enabling the computer system 501 to interact with a human user. Such software may include, but is not limited to, device drivers, operating systems, and applications software. Such computer readable media further includes the computer program product of the present disclosure for performing all or a portion (if processing is distributed) of the processing performed in implementing any portion of the invention. [0124] The computer code devices of the present embodiments may be any interpretable or executable code mechanism, including but not limited to scripts, interpretable programs, dynamic link libraries (DLLs), Java classes, and complete executable programs. Moreover, parts of the processing of the present embodiments may be distributed for better performance, reliability, and/or cost. [0125] The term “computer readable medium” as used herein refers to any non-transitory medium that participates in providing instructions to the processor 503 for execution. A computer readable medium may take many forms, including but not limited to, non-volatile media or volatile media. Non-volatile media includes, for example, optical, magnetic disks, and magneto-optical disks, such as the hard disk 507 or the removable media drive 508 . Volatile media includes dynamic memory, such as the main memory 504 . Transmission media, on the contrary, includes coaxial cables, copper wire and fiber optics, including the wires that make up the bus 502 . Transmission media also may also take the form of acoustic or light waves, such as those generated during radio wave and infrared data communications. [0126] Various forms of computer readable media may be involved in carrying out one or more sequences of one or more instructions to processor 503 for execution. For example, the instructions may initially be carried on a magnetic disk of a remote computer. The remote computer can load the instructions for implementing all or a portion of the present disclosure remotely into a dynamic memory and send the instructions over a telephone line using a modem. A modem local to the computer system 501 may receive the data on the telephone line and place the data on the bus 502 . The bus 502 carries the data to the main memory 504 , from which the processor 503 retrieves and executes the instructions. The instructions received by the main memory 504 may optionally be stored on storage device 507 or 508 either before or after execution by processor 503 . [0127] The computer system 501 also includes a communication interface 513 coupled to the bus 502 . The communication interface 513 provides a two-way data communication coupling to a network link 514 that is connected to, for example, a local area network (LAN) 515 , or to another communications network 516 such as the Internet. For example, the communication interface 513 may be a network interface card to attach to any packet switched LAN. As another example, the communication interface 513 may be an integrated services digital network (ISDN) card. Wireless links may also be implemented. In any such implementation, the communication interface 513 sends and receives electrical, electromagnetic or optical signals that carry digital data streams representing various types of information. [0128] The network link 514 typically provides data communication through one or more networks to other data devices. For example, the network link 514 may provide a connection to another computer through a local network 515 (e.g., a LAN) or through equipment operated by a service provider, which provides communication services through a communications network 516 . The local network 514 and the communications network 516 use, for example, electrical, electromagnetic, or optical signals that carry digital data streams, and the associated physical layer (e.g., CAT 5 cable, coaxial cable, optical fiber, etc.). The signals through the various networks and the signals on the network link 514 and through the communication interface 513 , which carry the digital data to and from the computer system 501 may be implemented in baseband signals, or carrier wave based signals. [0129] The baseband signals convey the digital data as unmodulated electrical pulses that are descriptive of a stream of digital data bits, where the term “bits” is to be construed broadly to mean symbol, where each symbol conveys at least one or more information bits. The digital data may also be used to modulate a carrier wave, such as with amplitude, phase and/or frequency shift keyed signals that are propagated over a conductive media, or transmitted as electromagnetic waves through a propagation medium. Thus, the digital data may be sent as unmodulated baseband data through a “wired” communication channel and/or sent within a predetermined frequency band, different than baseband, by modulating a carrier wave. The computer system 501 can transmit and receive data, including program code, through the network(s) 515 and 516 , the network link 514 and the communication interface 513 . Moreover, the network link 514 may provide a connection through a LAN 515 to a mobile device 517 such as a personal digital assistant (PDA) laptop computer, or cellular telephone. [0130] According to one embodiment there is described an method and apparatus for randomizing instructions to increase computer security. The process includes the steps of encrypting instructions in an inner processing system (IPS) of a processing system including a virtual machine (VM) that is composed of an outer processing system (OPS) and the IPS, transmitting the encrypted instructions to the outer processing system, decrypting the encrypted instructions at the OPS such that the decrypted instructions are out-of-band of the IPS and are not accessible by the IPS, executing the decrypted code via a stub routine in the virtual machine, translating the decrypted instructions to a set of OPS instructions using a Van Wijngaarden grammar specified as a simple two-layer translator for the IPS, and transmitting the translated instructions to the IPS. [0131] While aspects of the present disclosure have been described in conjunction with the specific embodiments thereof that are proposed as examples, alternatives, modifications, and variations to the examples may be made. Furthermore, it should be noted that, as used in the specification and the appended claims, the singular forms “a,” “an,” and “the” include plural referents unless the context clearly dictates otherwise.

Described herein is a method and apparatus to randomize instruction sets, memory registers, and pointers to increase computer security by increasing resource commitment requirements for malicious software, malicious computer users, or reverse engineers to understand the meaning of the new instruction sets, memory registers, and pointers.

FIELD OF THE INVENTION [0001] The present invention relates to a device used for baking food and other materials. More particularly, the invention relates to a conduction coil or mass used to conduct heat from a heat source into food to cook the interior of the food while the outside is also being baked or otherwise heated. BACKGROUND OF THE INVENTION [0002] Cooking food, such as by baking, consumes time, energy and money, but produces delicious foods for family and those we dine with. Ingredients are mixed and placed in a bowl, pan, pot or other cooking dish. The dish is heated in an oven, on the stove, in a broiler, outdoor grill or other methods. [0003] It would be of advantage in the art if a device could be provided that would save time, energy and/or money while producing the same or better quality dishes. [0004] Yet another advantage would be if the device was simple, easy to clean and safe to use. [0005] It would be another advance in the art if the device could be used to either heat or cool items such as food. [0006] Other advantages will appear hereinafter. SUMMARY OF THE INVENTION [0007] It has now been discovered that the above and other advantages of the present invention may be obtained in the following manner. Specifically, the present invention is a simple, high-efficiency instrument that uses highly thermally conductive materials to drive heat energy into and out of foods, food dishes, and other materials. The heat energy is transferred by solid conductive portions that are inserted into the material and by a conductive portion that remains outside the material. This arrangement quickly and naturally equalizes the temperature differences inside and outside of the material. Thus the invention provides a device for conducting heat or cooling from an external source, such as an oven or refrigerator, to the inside of a mixture of food or other materials that need to be heated, or cooled, internally as well as external heat or cooling. [0008] The device comprises a conductive object having at least one first portion such as a prong or rod that can be inserted into the material being processed, and a second portion capable of absorbing heat or cooling that is conducted to the at least one first portion and thus to the interior of the material. The device is preferably made from metals and preferably from copper, aluminum and alloys thereof. Other conductive materials are also within the scope of this invention. For example, silver is very conductive, but is not preferred due to its higher cost than aluminum or copper. BRIEF DESCRIPTION OF THE DRAWINGS [0009] For a more complete understanding of the invention, reference is hereby made to the drawings, in which: [0010] FIG. 1 is a perspective view of one embodiment of the present invention. [0011] FIG. 2 is a perspective view of another embodiment of the present invention. [0012] FIG. 3 is a perspective view of yet another embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT [0013] The present invention provides for substantial improvements in heating and/or cooling masses of material by conduction. When used to heat material, ovens are often used, but the device is also capable of absorbing and therefore conducting heat from other sources of heat, such as a barbeque grill, particularly if the grill has a closed cover or lid. Similarly, when used to cool material, refrigerators and freezers are often used. Other environments including ambient temperature will provide cooling energy that the device conducts to the interior of the material. [0014] FIG. 1 illustrates one embodiment of the present invention, 10 generally, that has a pair of rods 11 and 13 that are designed to be inserted into material that is to be heated or cooled internally. Rods 11 and 13 are each connected at one end to center mass 15 . Center mass 15 is shown as a coil but other shapes including a simple extension of rods 11 and 13 , a larger solid mass in a rectangular, cubic, round, donut or other shape is also within the scope of this invention. The function of rods 11 and 13 , or other shapes as noted below, is to transfer heat or cold that is conducted into them from center mass 15 so as to change the interior temperature of the material. The exterior of the material may or may not be simultaneously heated or cooled as desired. [0015] FIG. 2 illustrates an alternative embodiment 20 where rods 11 and 13 of FIG. 1 are replaced with coils 17 and 19 . These coils get larger at the end that is to be inserted into the material being heated or cooled to transfer more heat or cold to the inside. Alternatively, coils 17 and 19 can be uniform in size, or smaller at their ends. Other shapes besides rods or coils, such as flat blades, spoons, forks and other shapes are also effective. [0016] FIG. 3 shows yet another embodiment 30 which has one portion 21 for insertion into the material being heated or cooled and a second portion 23 for absorbing and conducting heat or cooling to the first portion 21 and thus to the interior of the material. As noted above, the shape of portions 21 and 23 is exemplary and not limiting. Other shapes that function to absorb heat or cooling and conduct the same into the interior of the material being treated are also fully within the scope of this invention. [0017] As noted above, the primary materials used for this project will be copper, aluminum, and their appropriate alloys. These materials will be extruded into a shape to maximize both strength and surface area, while having the mass to conduct adequate thermal energy into or out of the material. Each device will have one or more tines, which will be inserted into the material as described above. Some versions will have straight tines; others will have something of a cork-screw, embordering a coil of the same extrusion, acting as a radiator. This will speed the process of conduction into the material. The finished form will then be coated/ treated as needed by anodizing the aluminum or plating/treating the copper. This will be done for aesthetics and to prevent acids from leaching the base metal into the material that is to be heated or cooled. [0018] Also as noted above, the preferred materials, copper and aluminum, have been selected due to their high thermal conductivity; copper being 401 and aluminum being 237. Silver at 429 has the highest thermal conductivity of any metal but was not selected due to cost constraints. [0019] For the initial testing, 2 lb. sample materials were heated from an internal temperature of 45 degrees Fahrenheit to 160 degrees Fahrenheit. The devices of this invention used only 54-59% of the energy required compared to the device not being used. Using the device of this invention has been shown to cut cooking time nearly in half (with identical cooking results), or lower cooking temperature settings required for the same cooking time. [0020] If just half of U.S. households used their oven only once a week, using the present invention, would save approximately 300 million dollars a year. In addition, many mass food producers, such as restaurants, caterers, schools, military mess units etc. could also use the present invention to save time and money. This will appeal to families to more quickly create a meal, and also make cooking more attractive to those who think it just takes too much time. The present invention will also appeal to those who want to conserve energy for cost savings, as well as for the environment. [0021] While particular embodiments of the present invention have been illustrated and described, it is not intended to limit the invention, except as defined by the following claims.

A device for heating or cooling material, having at least one first conductive portion sized to be inserted into the material; and at least one second conductive portion conductively attached to the first portion. the second portion is sized to absorb and conduct heat or cooling from a source proximate the second portion into the first portion. The first portion heats or cools the interior of the material.

CROSS-REFERENCE TO RELATED APPLICATIONS U.S. Provisional Patent Application Ser. No. 61/930,972, filed Jan. 24, 2014 is incorporated herein by reference in its entirety. In some embodiments, any feature or combination of features described in the present document may be combined with any feature of combination of features described in U.S. Provisional Patent Application Ser. No. 61/930,972. PCT Application No. PCT/IB2013/000203, filed Feb. 17, 2013 is incorporated herein by reference in its entirety. In some embodiments, any feature or combination of features described in the present document may be combined with any feature of combination of features described in application PCT/IB2013/000203. British Patent Application No. GB1202706.6, filed Feb. 16, 2012 is incorporated herein by reference in its entirety. In some embodiments, any feature or combination of features described in the present document may be combined with any feature of combination of features described in British Patent Application No. GB1202706.6. U.S. Provisional Patent Application Ser. No. 61/602,093, filed Feb. 23, 2012 is incorporated herein by reference in its entirety. In some embodiments, any feature or combination of features described in the present document may be combined with any feature of combination of features described in U.S. Provisional Patent Application Ser. No. 61/602,093. FIELD AND BACKGROUND OF THE INVENTION The present invention relates to gastrointestinal capsules (GICs). Intestinal constipation is a widespread gastrointestinal motility disorder. Various treatment programs are known, employing dietary modifications and supplements, laxatives, and suppositories. In severe cases, surgery may be indicated. Constipation may be considered a symptom, and care must be taken, in treating the symptom, not to exacerbate or aggravate the general condition of the patient. Thus, by way of example, the frequent or long-term use of laxatives may be detrimental, as such laxatives may compromise the ability of the body to independently effect bowel movements. An ingestible gastrointestinal capsule for mechanically stimulating a segment of the gastrointestinal wall is disclosed by U.S. Patent Publication No. 20090318841, which is incorporated by reference for all purposes as if fully set forth herein. However, the present inventor has recognized a need for improved gastrointestinal capsules and treatment methods utilizing such capsules. SUMMARY OF THE INVENTION According to the teachings of the present invention there is provided a gastrointestinal capsule (GIC) including: (a) a capsule housing having a longitudinal axis; (b) at least one thrusting mechanism, disposed within the housing, the thrusting mechanism adapted to exert radial forces on the housing, in a radial direction with respect to the axis, such that, when the capsule is disposed within a gastrointestinal tract of a user, and the mechanism is in an active mode, the gastrointestinal capsule exerts forces against, or in a direction of the walls of the tract; and (c) a power supply adapted to power the mechanism, wherein a ratio of the radial forces to axial forces exerted in an axial direction with respect to the axis, on the housing, by the thrusting mechanism, is at least 1:1, at least 1.25:1, at least 1.5:1, at least 2:1, at least 3:1, at least 4:1, or at least 5:1. According to yet another aspect of the present invention there is provided a gastrointestinal capsule including: (a) a housing; (b) a thrusting mechanism, disposed within the housing, the mechanism having an active mode and a passive mode, with respect to the active mode, the mechanism adapted to exert a radial force on the housing, whereby, when the capsule is disposed within a gastrointestinal tract of a user, and the mechanism is in the active mode, the gastrointestinal capsule stimulates the walls of the tract; and (c) a battery adapted to power the mechanism, wherein the active mode includes a series of at least two pulses of the radial force, the series having a first duration, the passive mode has a second duration, and wherein an activation cycle is defined by the series of pulses followed by the second duration, and wherein the first duration is within a range of 1-10 seconds. According to still further features in the described preferred embodiments, the ratio is at most 20:1, at most 12:1, at most 10:1, at most 8:1, at most 7:1, or at most 6:1. According to still further features in the described preferred embodiments, the ratio is within a range of 1:1 to 15:1, 2.5:1 to 15:1, 2.5:1 to 10:1, 2.5:1 to 8:1, or 2.5:1 to 6:1. According to still further features in the described preferred embodiments, the at least one thrusting mechanism includes an axial perturbation arrangement having: (i) a motor electrically connected to the power supply; and (ii) an urging mechanism, associated with, and driven by, the motor, the urging mechanism adapted to exert the axial forces. According to still further features in the described preferred embodiments, the urging mechanism includes: a motor shaft, disposed at least partially in a direction along the longitudinal axis, the shaft being operatively connected to, and driven by, the motor; and a thrusting weight associated with the shaft, the urging mechanism further adapted to at least periodically urge the weight along the shaft, to deliver the axial forces. According to still further features in the described preferred embodiments, the urging mechanism further includes a stopper or cap, adapted to receive a distal end of the shaft, the stopper or cap impinging against an inner wall of the capsule housing. According to still further features in the described preferred embodiments, the urging mechanism further includes a spring associated with the motor shaft, the urging mechanism being adapted such that, in a first state, the spring is compressed, and such that, in a second state, the spring is released against the weight, to urge the weight along the shaft, to deliver the axial forces against the capsule housing. According to still further features in the described preferred embodiments, the motor shaft passes through the weight, the motor shaft has an external interrupted thread, and the weight has a threaded internal surface generally complementary to a threading of the interrupted thread, whereby, in the first state, the external interrupted thread engages the threaded internal surface, and in the second state, the threaded internal surface is disengaged and longitudinally free with respect to the interrupted thread. According to still further features in the described preferred embodiments, the motor shaft passes through the weight, the weight being adapted to turn with the shaft, the motor shaft having an external interrupted thread, and the weight having a threaded internal surface generally complementary to a threading of the interrupted thread, the urging mechanism being further adapted such that in the first state, the external interrupted thread engages the threaded internal surface to compress the spring, and in a second state, the threaded internal surface is disengaged and longitudinally free with respect to the interrupted thread, such that the spring is released against the weight. According to still further features in the described preferred embodiments, the thrusting mechanism includes a rotatably mounted eccenter, the thrusting mechanism being adapted to rotate the eccenter to exert the radial forces. According to still further features in the described preferred embodiments, the thrusting mechanism is configured to have the active mode and a passive mode with respect to the active mode, the active mode including a series of at least two pulses of the radial forces, wherein the series has a first duration, the passive mode has a second duration, and wherein the second duration exceeds the first duration. According to still further features in the described preferred embodiments, the first duration and the second duration define an activation cycle, the thrusting mechanism being configured such that the activation cycle has a period within a range of 5-60 seconds, 7-40 seconds, 8-30 seconds, 10-30 seconds, or 12-25 seconds. According to still further features in the described preferred embodiments, the first duration and the second duration define an activation cycle, the thrusting mechanism being configured such that the activation cycle has a period of at least 5, at least 6, at least 7, at least 8, at least 10, at least 12, or at least 15 seconds, and/or at most 60, at most 40, at most 30, at most 25, or at most 20 seconds. According to still further features in the described preferred embodiments, the thrusting mechanism is configured such that the first duration is within a range of 1-10 seconds, 2-8 seconds, or 2.5-6 seconds. According to still further features in the described preferred embodiments, the thrusting mechanism is configured such that a net force exerted by the capsule on an external environment is at least 400 grams force, at least 450 grams force, at least 500 grams force, or at least 600 grams force. According to still further features in the described preferred embodiments, the thrusting mechanism is configured such that the net force is an instantaneous net force of at least 800 grams force, at least 1000 grams force, at least 1200 grams force, at least 1400 grams force, or at least 1500 grams force. According to still further features in the described preferred embodiments, the thrusting mechanism is configured to exert the radial forces on the housing to attain a vibrational frequency, of the housing, within a range of 12 Hz to 80 Hz. According to still further features in the described preferred embodiments, the thrusting mechanism is configured such that this range is 12 Hz to 70 Hz, 15 Hz to 60 Hz, 15 Hz to 50 Hz, 18 Hz to 45 Hz, or 18 Hz to 40 Hz. According to still further features in the described preferred embodiments, the thrusting mechanism is configured such that this vibrational frequency is at least 15 Hz, at least 18 Hz, at least 20 Hz, or at least 22 Hz. According to still further features in the described preferred embodiments, the thrusting mechanism is configured such that this vibrational frequency is at most 75 Hz, at most 70 Hz, at most 60 Hz, at most 50 Hz, at most 45 Hz, or at most 40 Hz. According to still further features in the described preferred embodiments, the axial arrangement is adapted to exert the axial forces in opposite directions. According to still further features in the described preferred embodiments, the axial arrangement is adapted to deliver at least a portion of the axial forces in a knocking mode. According to still further features in the described preferred embodiments, the thrusting mechanism has a first individual motor for delivering the radial forces and a second individual motor for delivering the axial forces. According to still further features in the described preferred embodiments, the first individual motor and the second individual motor are disposed on different sides of the capsule, with respect to the axis. According to still further features in the described preferred embodiments, the thrusting mechanism is adapted such that when the capsule is disposed within the tract, and the mechanism is in the active mode, the capsule stimulates the walls of the tract. According to still further features in the described preferred embodiments, the thrusting mechanism includes a controller, electrically attached to the power supply, the controller adapted to control the thrusting mechanism. According to still further features in the described preferred embodiments, the controller is physically isolated from all motors within the housing. According to still further features in the described preferred embodiments, the controller is physically isolated, by at least 2 mm, from all motors within the housing. According to still further features in the described preferred embodiments, the thrusting mechanism is adapted to exert a radial force on the housing, whereby, when the capsule is disposed within a gastrointestinal tract of a user, and the thrusting mechanism is in the active mode, the gastrointestinal capsule induces a peristaltic wave in the walls of the tract. According to still further features in the described preferred embodiments, the length of the GIC is at most 28 mm, at most 26 mm, at most 25 mm, at most 24 mm, at most 22 mm, at most 20 mm, at most 18 mm, at most 15 mm, or at most 12 mm. According to still further features in the described preferred embodiments, the weight of the GIC is at most 25 grams, at most 22 grams, at most 20 grams, at most 17 grams, at most 15 grams, at most 12 grams, or at most 10 grams. According to yet another aspect of the present invention there is provided a therapeutic method for mechanically stimulating a wall of a segment of a mammalian gastrointestinal tract of a user by means of a gastrointestinal capsule, the method including: (a) providing the gastrointestinal capsule; (b) administering at least one treatment session, each treatment session including: (i) delivering the gastrointestinal capsule into the tract; and (ii) effecting activation of a thrusting mechanism of the gastrointestinal capsule to achieve mechanical stimulation of the wall of the gastrointestinal tract. According to still further features in the described preferred embodiments, the at least one treatment session includes a plurality of the treatment sessions. According to still further features in the described preferred embodiments, at least one of the treatment sessions is administered per week, over a treatment period extending for at least two weeks, at least three weeks, at least four weeks, at least five weeks, at least six weeks, or at least eight weeks. According to still further features in the described preferred embodiments, at least 1.5, at least 1.75, at least 2, at least 2.5, or at least 3 of the treatment sessions is administered per week of the treatment period. According to still further features in the described preferred embodiments, a frequency of the treatment sessions administered to the user is within a range of 1.5 to 6 per week of the treatment period. According to still further features in the described preferred embodiments, the frequency is within a range of 1 to 7, 1.5 to 7, 1.5 to 6, 1.5 to 5, 1.5 to 4, 1.5 to 3.5, 1.5 to 3, 2 to 6, 2 to 5, 2 to 4, 2 to 3.5, or 2 to 3, per week of the treatment period. According to still further features in the described preferred embodiments, within each the treatment session, the activation of the thrusting mechanism is performed for a duration effective to achieve the mechanical stimulation of the wall of the gastrointestinal tract. According to still further features in the described preferred embodiments, within each treatment session, the activation of the thrusting mechanism is performed for a duration effective to increase a frequency of spontaneous bowel movements of the user. According to still further features in the described preferred embodiments, within each treatment session, the activation of the thrusting mechanism is performed for a duration effective to increase a frequency of spontaneous bowel movements of the user by at least 25%, at least 50%, at least 75%, or at least 100%. According to still further features in the described preferred embodiments, within each treatment session, the activation of the thrusting mechanism is performed for a duration effective to at least partially relieve, or to completely relieve, a condition of constipation of the user. According to still further features in the described preferred embodiments, the vibration frequency and relaxation period may be varied, within a single treatment period, in order to prevent habituation. According to still further features in the described preferred embodiments, the delivering of the GIC is performed via oral insertion. According to still further features in the described preferred embodiments, the delivering of the GIC is performed by inserting the GIC into the tract via a rectal opening of the user. BRIEF DESCRIPTION OF THE DRAWINGS The invention is herein described, by way of example only, with reference to the accompanying drawings. With specific reference now to the drawings in detail, it is stressed that the particulars shown are by way of example and for purposes of illustrative discussion of the preferred embodiments of the present invention only, and are presented in the cause of providing what is believed to be the most useful and readily understood description of the principles and conceptual aspects of the invention. In this regard, no attempt is made to show structural details of the invention in more detail than is necessary for a fundamental understanding of the invention, the description taken with the drawings making apparent to those skilled in the art how the several forms of the invention may be embodied in practice. Throughout the drawings, like-referenced characters are used to designate like elements. In the drawings: FIG. 1 is a schematic exploded view of a GIC according to some embodiments of the present invention; FIG. 2A is a cut-open, perspective view of the GIC provided in FIG. 1 ; FIG. 2B is a side view of the cut-open GIC of FIG. 2A ; FIG. 3A is a schematic, top view of a cut-open GIC according to some embodiments of the present invention; FIG. 3B is a side view of the cut-open GIC of FIG. 3A ; FIG. 3C is a partial perspective view of the cut-open GIC of FIG. 3A ; FIG. 3D is another partial view of cut-open GIC 300 , showing a magnified perspective view of an external interrupted thread of screw shaft, according to one embodiment of the invention; FIG. 4A is a sectional illustration of a screw shaft and a weight forming part of GIC 300 in a first state, according to an embodiment of the invention; FIG. 4B is a sectional illustration of the screw shaft and the weight of FIG. 4A , in a second state, according to an embodiment of the invention; and FIG. 4C is a sectional perspective view of the weight of FIGS. 4A and 4B . DESCRIPTION OF THE PREFERRED EMBODIMENTS The principles and operation of the inventive gastrointestinal capsules, and the treatment methods utilizing such capsules, may be better understood with reference to the drawings and the accompanying description. Before explaining at least one embodiment of the invention in detail, it is to be understood that the invention is not limited in its application to the details of construction and the arrangement of the components set forth in the following description or illustrated in the drawings. The invention is capable of other embodiments or of being practiced or carried out in various ways. Also, it is to be understood that the phraseology and terminology employed herein is for the purpose of description and should not be regarded as limiting. FIG. 1 is a schematic exploded view of a GIC 100 according to some embodiments of the present invention. GIC 100 may include a capsule housing or shell 105 (best seen in FIG. 2A ) having complementary (e.g., male and female) components 105 A, 105 B. Within the capsule housing may be disposed a thrusting mechanism that may include a motor 110 and a circuit board 122 having a CPU, microprocessor or controller 120 . Within the capsule housing may further be disposed a power supply such as at least one battery 140 , an electrically conductive bridge such as metal bridge 130 , and an insulator 138 . A cut-open, perspective view of GIC 100 is provided in FIG. 2A . Three disc-shaped batteries 140 and circuit board 122 may be held together by metal bridge 130 . Bridge 130 may be adapted to make electrical contact with a broad face of the battery distal to circuit board 122 , and may provide power to circuit board 122 . Batteries 140 may also power motor 110 , e.g., via conducting wires (not shown) attached to circuit board 122 . The thrusting mechanism may be adapted to deliver to exert radial forces on capsule housing 105 . In one embodiment, motor 110 is an eccentric motor having an eccentric weight 112 . As motor 110 spins in a generally normal fashion with respect to a longitudinal axis 108 of GIC 100 , radial forces are exerted on housing 105 . A side view of the cut-open GIC 100 is provided in FIG. 2B . The inventive GIC is adapted such that, after ingestion thereof, the GIC is carried by bodily forces through the upper and lower gastrointestinal tracts. Ultimately, the GIC may be naturally evacuated along with the stool. In accordance with some embodiments of the present invention is provided the GIC may be adapted to repeatedly vibrate within the gastrointestinal walls of the user. The GIC may be automatically activated at a predefined time following ingestion. Similarly, a timing mechanism of (or associated with) CPU 120 may be initiated at, or prior to, ingestion. In accordance with some embodiments of the present invention, activation of the GIC may be set to automatically occur 2 to 12 hours, 2 to 10 hours, or 2 to 8 hours following ingestion, and more typically, 6 to 10 hours or 6 to 8 hours following ingestion. Such a (typically pre-determined) time delay may match the transit time in which the GIC reaches the large bowel via the upper gastrointestinal tract. The transit time within the large bowel may be significantly longer, in the range of 2 to 5 days, depending on whether the transit time is normal or prolonged, as in cases of constipation. In such cases, the time delay for activation may range between 6 and 24 hours. Once activated, the inventive GICs may be adapted to agitate for at least 15 minutes, at least 30 minutes, at least 1 hour, at least 1.5 hours, at least 2 hours, at least 2.5 hours, or at least 3 hours, including intermittent periods of rest. Typically, the inventive GICs may be adapted to agitate for less than 8 hours, including intermittent periods of rest. FIG. 3A is a schematic, top view of a cut-open GIC 300 according to some embodiments of the present invention. GIC 300 may include a capsule housing or shell 305 having complementary components 305 A, 305 B. Within capsule housing 305 may be disposed a thrusting mechanism that may include a motor 310 and a circuit board 322 having a CPU, microprocessor or controller 320 . Within the capsule housing may further be disposed a power supply such as at least one battery 340 , and an electrically conductive bridge such as metal bridge 330 . An insulating barrier (shown in FIG. 1 ) may be disposed between battery 340 and bridge 330 , to avoid short-circuiting. As shown in FIG. 3A , two (by way of example) disc-shaped batteries 340 and circuit board 322 may be held together by metal bridge 330 . Bridge 330 makes electrical contact with a broad face of the battery distal to circuit board 322 , and may provide power to circuit board 322 . Batteries 340 may also power motor 310 , e.g., via conducting wires (not shown) attached to circuit board 322 . Microprocessor or controller 320 may be mechanically and electrically attached to circuit board 322 by means of electrically conductive connectors 324 . As described hereinabove, the thrusting mechanism may be adapted to exert eccentric or radial forces on capsule housing 305 . The motor may be an eccentric motor having an eccentric weight 312 . As motor 310 spins in a generally normal fashion with respect to a longitudinal axis of GIC 300 , radial forces are exerted on housing 305 . GIC 300 may be equipped with an auxiliary axial perturbation arrangement such as axial perturbation arrangement 350 , adapted to effect axial forces on housing 305 . The axial perturbation arrangement may be part of the thrusting mechanism. In the exemplary embodiment provided in FIG. 3A , perturbation arrangement 350 includes a motor 368 that is electrically connected to batteries 340 . Motor 368 may be disposed at a distal end of GIC 300 , with respect to motor 310 . Axial perturbation arrangement 350 may further include a motor screw or screw shaft such as axial motor screw shaft 364 , mechanically associated with, and driven by, motor 368 , and aligned in a generally axial fashion within GIC 300 , typically along, generally along, or parallel to a longitudinal axis 308 of the capsule; a spring 362 , which may be concentrically disposed on shaft 364 , proximal to motor 310 ; a weight 360 , which may be aligned in an axial fashion within GIC 300 , and which may typically be disposed between spring 362 and motor screw 364 ; a stopper 366 , adapted to receive a distal end (with respect to motor 310 ) of motor screw 364 , and impinging against an inner wall 365 of capsule housing 305 . A side view of cut-open GIC 300 is provided in FIG. 3B . FIG. 3C is a partial view of cut-open GIC 300 , showing a magnified perspective view of perturbation arrangement 350 , according to one embodiment of the invention. FIG. 3D is another partial view of cut-open GIC 300 , showing a magnified perspective view of an external interrupted thread 363 of screw shaft 364 , according to one embodiment of the invention. Weight 360 , which may be generally of an annular shape, may advantageously have a threaded internal surface 369 , shown clearly in FIG. 4C , that may be generally circumferentially complementary to the threading of interrupted thread 363 . The interrupted portion 365 of interrupted thread 363 may have a twin interrupted portion on the (radially and longitudinally) opposite side of screw shaft 364 . In one exemplary mode of operation of perturbation arrangement 350 , screw shaft 364 , driven by motor 368 , engages the threaded internal surface 369 of weight 360 , such that weight 360 is drawn towards spring 362 , and compression of spring 362 ensues (“State 1 ”). As screw shaft 364 continues to turn, the interrupted portion 365 of interrupted thread 363 meets the threaded internal surface 369 of weight 360 , as seen clearly in FIG. 4B , whereupon weight 360 becomes disengaged and longitudinally free with respect to interrupted thread 363 of shaft 364 . Spring 362 , disposed in a compressed position, is now free to longitudinally extend (“State 2 ”), forcefully urging weight 360 towards stopper 366 , and thereby axially impacting capsule housing 305 . As screw shaft 364 continues to turn, screw shaft 364 again engages the threaded internal surface 365 of weight 360 , whereby perturbation arrangement 350 again reassumes State 1 . We have found that the ratio of the radial forces exerted to the axial forces exerted, on the housing, may be at least 1:1, at least 1.25:1, or at least 1.5:1, and more typically, at least 2:1, at least 3:1, at least 4:1, or at least 5:1. Without wishing to be bound by theory, the inventor believes that the radial forces provide the primary effect of stimulating the walls of the lower gastrointestinal tract. Nonetheless, the axial forces may be useful in the locomotion of the capsule, particularly in regions that are partially clogged or blocked by chyme. Since the power supply is limited, a relatively high ratio of the radial forces exerted to the axial forces exerted may be critical in delivering the requisite stimulation to the walls of the tract. The ratio of forces may be defined as the sum of the radial forces delivered to the sum of the axial forces delivered, over the entire time of activity of the GIC. For a GIC having a substantially repeating period, the ratio of forces may be defined as the sum of the radial forces delivered to the sum of the axial forces delivered, over one complete period. In one embodiment, the GIC may be introduced to the body of the user via oral insertion. In one embodiment, the GIC may be introduced into a lower end of the large intestine via the rectal opening. The general procedure may be similar to the introduction of a suppository. A first end of the GIC, which may have a tapered shape, and may be lubricated, may be placed at the rectal opening and gently pushed into the rectum. The GIC may be manually urged up the rectal tract, to a distance of several centimeters and up to about eight centimeters from the rectal opening. Deeper insertion, to the end of the rectum distal to the rectal opening, may be achieved by means of an insertion apparatus. Such an apparatus may include a long, smooth rod, preferably made of, or coated with, a flexible, smooth, biocompatible substance such as silicone. At a first end of the apparatus may be disposed a securing mechanism adapted to secure the GIC until the GIC has reached the desired position within the rectum, and a release mechanism adapted to release the GIC, upon demand. The securing and release mechanism may include a spring. Such an apparatus, whose structure or structures will be readily apparent to those of ordinary skill in the art, may enable the introduction of the GIC through the rectal tract, to a position of at least 8 cm, at least 10 cm, at least 12 cm, or at least 14 cm from the rectal opening. In an actual capsule prototype, the capsule length was 24.2 mm, and the capsule diameter was 11.3 mm. The shell was made of medical Makrolon® 2458, a biocompatible material. The voltage was 4.5 Volts. Following ingestion of the capsule, the vibrating sequence begins after a predetermined amount of time (delay). This delay (6 or 8 hours) may allow the capsule to reach the large intestine before the vibrating sequence is initiated. The capsule may be activated by an electromagnetic signal carrying an activation code. The activation may be confirmed, e.g., by vibration of the capsule (e.g., 3 consecutive vibrations), or by any of various visual (e.g., LED) or audio signals, to ensure that the output (or the programming result) is identical to the requirements indicated by the physician. The capsule typically contains an electromechanical system that operates a mechanically controlled vibrating mechanism adapted to induce peristaltic wave activity in the large intestine. A computerized algorithm may provide the vibration rate and relaxation period in order to prevent habituation. Various therapeutic modes may be pre-programmed or pre-set for the GIC. For example: Mode A: activation delay is set to 8 hours. The vibration rate is 180 vibration cycles per hour, each cycle consisting of 4 seconds of a vibration period and 16 seconds of a repose (relaxation) period, corresponding, on a per hour basis, to 12 minutes of vibration periods and 48 minutes of rest intervals or periods. Mode B: activation delay is set to 6 hours. The vibration rate is 240 vibration cycles per hour, each cycle consisting of 4 seconds of a vibration period and 11 seconds of a repose period, corresponding, on a per hour basis, to 16 minutes of vibration periods and 44 minutes of rest intervals or periods. To ensure that the capsule has reached the large intestine, the capsule is equipped with an activation delay mechanism (typically having a pre-determined delay of 6-8 hours) that defines the time period between activation (and typically, ingestion) and the initial onset of the vibrating phase. The capsule may be advantageously activated by qualified medical personnel. In some cases, the capsule may be activated by the user. In some embodiments of the present invention, various dedicated GI capsules may be produced, that may be pre-programmed according to the needs of various patients. Such embodiments may not require the transmitter and antenna. In some embodiments employing programming according to the needs of the patient: A. The capsule may be equipped with an electronic circuit, transmitter and antenna, adapted to receive an external signal regarding the mode of activation required. B. The capsule may be activated via a dedicated base unit. The base unit may include an electronic circuit, a power supply (batteries), software and a socket adapted to receive the capsule. The base unit has various programming modes that enable the medical personnel to select the appropriate one according to the specific needs of the patient/user, e.g., according to the severity of the constipation (e.g., Rome II, Rome III, etc.). C. The activation of the capsule with the selected mode of operation may be performed by the dedicated base unit, which may transmit to the capsule the programmed mode, by a simple push of a button on the base unit. D. The capsule may be adapted to signal that receipt of the mode of work chosen, and after this signal, the capsule may be activated and may then be ready to be swallowed. The GICs of the present invention are effective in treating various levels of functional constipation, including Rome I, Rome II and Rome III criteria (severity) levels. The GICs of the present invention may be effective in treating more serious levels/criteria of constipation. The GICs of the present invention have been found to be effective in relieving functional constipation accompanied by abdominal pain, such as irritable bowel syndrome with constipation (IBS-C). The GICs of the present invention have been found to be effective in relieving functional constipation, such as chronic idiopathic constipation (CIC). The Rome III criteria for functional constipation are provided below. Rome III diagnostic criteria for functional constipation, based on: ROME III: The Functional Gastrointestinal Disorders, Third Edition ( October, 2006) 1. Must include two or more of the following: a. Straining during at least 25% of defecations b. Lumpy or hard stools in at least 25% of defecations c. Sensation of incomplete evacuation for at least 25% of defecations d. Sensation of anorectal obstruction/blockage for at least 25% of defecations e. Manual maneuvers to facilitate at least 25% of defecations (e.g., digital evacuation, support of the pelvic floor) f. Fewer than three defecations per week 2. Loose stools are rarely present without the use of laxatives 3. Insufficient criteria for irritable bowel syndrome * Criteria fulfilled for the last 3 months with symptom onset at least 6 months prior to diagnosis The Rome II diagnostic criteria for functional constipation are similar, but the timeframe is more relaxed: at least 12 weeks, which need not be consecutive, in the preceding 12 months. According to one aspect of the present invention there is provided a method for mechanically stimulating a wall of a segment of a mammalian gastrointestinal tract of a user by means of a gastrointestinal capsule, the method including the steps of: (a) providing at least one capsule (preferably any one of the capsules disclosed herein); and (b) administering at least one treatment session, each treatment session including: (i) delivering the gastrointestinal capsule into the tract; and (ii) effecting activation of a thrusting mechanism of the gastrointestinal capsule to achieve mechanical stimulation of the wall of the gastrointestinal tract. The at least one treatment session may advantageously include a plurality of treatment sessions. Typically, at least one of the treatment sessions is administered per week, over a treatment period extending for at least two weeks, at least three weeks, at least four weeks, at least five weeks, at least six weeks, or at least eight weeks. At least 1.5, at least 1.75, at least 2, at least 2.5, or at least 3 of the treatment sessions may be administered per week of the treatment period. In some embodiments, the frequency of the treatment sessions administered to the user is within a range of 1.5 to 7 per week of the treatment period. In some embodiments, the frequency is within a range of 1 to 7, 1.5 to 6, 1.5 to 7, 1.5 to 6, 1.5 to 5, 1.5 to 4, 1.5 to 3.5, 1.5 to 3, 2 to 6, 2 to 5, 2 to 4, 2 to 3.5, or 2 to 3, per week of the treatment period. In some embodiments, within each treatment session, the activation of the thrusting mechanism is performed for a duration effective to achieve mechanical stimulation of the wall of the gastrointestinal tract. In some embodiments, within each treatment session, the activation of the thrusting mechanism is performed for a duration effective to increase a frequency of spontaneous bowel movements of the user. In some embodiments, within each treatment session, the activation of the thrusting mechanism is performed for a duration effective to increase a frequency of spontaneous bowel movements of the user by at least 25%, at least 50%, at least 75%, or at least 100%. In some embodiments, within each treatment session, the activation of the thrusting mechanism is performed is performed for a duration effective to at least partially relieve a condition of constipation of the user. In some embodiments, within each treatment session, the activation of the thrusting mechanism is performed for a duration effective to completely relieve a condition of constipation of the user. EXAMPLE Reference is now made to the following example, which together with the above description, illustrate the invention in a non-limiting fashion. Clinical trials on patients were performed using the GIC described with reference to FIGS. 1, 2A and 2B . The study included 22 subjects, 2 males and 20 females, aged between 19 to 65 years, who were found to be appropriate for the study. 20 subjects completed the study according to the protocol, 2 subjects withdrew their consent. Patients were followed for 14 days on their normal bowel movement and medication consumption. After 14 days the first capsule was administered and extraction of the capsule was confirmed up to day 21 in the study. During this week, the patient was followed to eliminate safety concerns. Once the first capsule extraction was confirmed, the patients were invited to the clinic twice a week for capsule administration and follow-up. During the bi-weekly visits, a capsule was activated by the study nurse and administered. Prior capsule extraction was verified using a stool collection kit. During these visits, satisfactory improvement of the symptoms/condition was assessed by the patient. After the initial, two-week baseline period, in which the number of spontaneous bowel movements was recorded, the GIC was administered about twice per week for a period of close to 7 weeks. The activation delay of the capsules was set to 8 hours. The vibration rate was 180 vibration cycles per hour, each cycle consisting of 4 seconds of a vibration period and 16 seconds of a repose period. The motor operated at 12,000 RPM (200 Hz), such that the thrusting mechanism exerted radial forces on the capsule housing at a vibration frequency of about 27 Hz. The average force exerted by the vibrations was 64 grams force (gf), while the maximal (instantaneous) force exerted was about 176 gf. Following the activation delay, the therapeutic treatment was conducted for about 2-2.5 hours. Efficacy was assessed by the increase in spontaneous bowel movements per week during the 7.5 weeks of treatment, as compared to a two-week baseline period. The efficacy assessment was performed for the Per Protocol population. All tests applied were two-tailed, and p value of 5% or less was considered statistically significant. The data was analyzed using SAS® version 9.1 for Windows (SAS Institute, Cary, N.C.). An increase in the mean number of spontaneous bowel movements per week was observed (see Table 1). This increase was found to be statistically significant (Mean increase=1.78, Standard deviation=1.09, p<0.001), as shown in Table 2. The mean number of spontaneous bowel movements per week of the treatment program is provided in Table 3. After the 7.5 weeks of treatment, 20% of the subjects no longer exhibited the Rome III criteria for CIC. For the group as a whole (20 subjects), the average number of idiopathic constipation criteria was reduced from 5.5 (out of 6 total) to 3.2 (p<0.001). 50% of the subjects displayed a higher number of bowel movements, on a weekly basis, and 67% of the subjects exhibited improved parameters regarding stool hardness and straining at defecation. Following the study, the status of the patients was monitored for a period of 6 months. With regard to constipation, it was found that after this six-month period, over 40% of the patients continued to enjoy an improved situation, while the situation of about 90% of the patients was better or unchanged. With regard to the CIC group of subjects (10 in all), after the 7.5 weeks of treatment, 2 of the subjects (20%) no longer exhibited the Rome III criteria for CIC. Within the CIC group, the average number of idiopathic constipation criteria was reduced from 5.7 to 3.2 (p≦0.004). 50% of the subjects displayed a higher number of bowel movements, on a weekly basis, and 80% of the subjects exhibited improved parameters regarding straining at defecation. With regard to the C-IBS group of subjects (10 in all), after the 7.5 weeks of treatment, 5 of the subjects (50%) no longer exhibited the Rome III criteria for C-IBS. Within the C-IBS group, 3 of the subjects (30%) experienced reduced abdominal pain. TABLE 1 2 weeks Treatment Change Site Subject baseline period Change (%) 1 1 2.50 5.40 2.90 116% 2 2.00 2.33 0.33 15% 3 1.00 3.43 2.43 240% 4 2.00 4.34 2.34 117% 5 2.50 3.50 1.00 40% 6 2.50 2.33 −0.17 −8% 7 1.50 3.50 2.00 133% 8 2.50 2.63 0.13 5% 9 3.23 6.43 3.20 103% 10 2.00 2.63 0.63 32% 13 3.27 5.36 2.10 64% 14 1.00 1.96 0.96 96% 18 3.50 6.00 2.50 71% 19 2.69 4.25 1.56 58% 22 2.00 4.90 2.90 145% 26 3.00 4.00 1.00 33% 27 1.00 2.20 1.20 120% 2 3 2.33 5.10 2.77 119% 4 2.00 4.38 2.38 119% 6 1.65 5.13 3.49 212% TABLE 2 Mean Number of Spontaneous bowel movements 2 weeks Treatment per period baseline period Change Mean 2.21 3.99 1.78 Std 0.74 1.36 1.09 Min 1.00 1.96 −0.17 Median 2.17 4.13 2.05 Max 3.50 6.43 3.49 P <0.001 TABLE 3 Mean Number of Spon- taneous bowel Baseline Treatment movements 1st 2nd 1st 2nd 3rd 4th 5th 6th 7th per week week week week week week week week week week Mean 2.30 2.30 4.05 3.30 3.80  4.20 4.85 4.05 3.65 Std 1.34 1.08 1.85 1.26 1.85  2.31 2.21 2.04 1.93 Min 1.0  1.0  1.0  1.0  1.0  1.0 2.0  1.0  1.0  Median 2.0  2.0  3.5  3.0  3.0  4.0 5.5  4.0  3.5  Max 7.0  5.0  7.0  6.0  7.0  12.0  8.0  8.0  7.0  *Last Observation Carry Forward (LOCF): for patients with no data or missing data on 7th treatment week, their data from 6th treatment week was taken as final observation. It will be appreciated that certain features of the invention, which are, for clarity, described in the context of separate embodiments, may also be provided in combination in a single embodiment. Conversely, various features of the invention, which are, for brevity, described in the context of a single embodiment, may also be provided separately or in any suitable sub-combination. Although the invention has been described in conjunction with specific embodiments thereof, it is evident that many alternatives, modifications and variations will be apparent to those skilled in the art. Accordingly, it is intended to embrace all such alternatives, modifications and variations that fall within the spirit and broad scope of the appended claims. All publications, patents and patent applications mentioned in this specification are herein incorporated in their entirety by reference into the specification, to the same extent as if each individual publication, patent or patent application was specifically and individually indicated to be incorporated herein by reference. In addition, citation or identification of any reference in this application shall not be construed as an admission that such reference is available as prior art to the present invention.

A gastrointestinal capsule (GIC) including a capsule housing having a longitudinal axis; a thrusting mechanism, disposed within the housing; and a battery adapted to power the and a battery adapted to power the thrusting mechanism; the thrusting mechanism having an active mode, and a passive mode with respect to the active mode, the thrusting mechanism adapted to exert a radial force on the housing, in a radial direction with respect to the axis, such that when the capsule is disposed within a gastrointestinal tract of a user, and the mechanism is in the active mode, the gastrointestinal capsule stimulates a wall of the tract; the active mode including a series of at least two pulses of the radial force, the series having a first duration, the passive mode having a second duration, wherein an activation cycle is defined by the series of pulses followed by the second duration.

FIELD OF THE INVENTION The present invention relates to motorized scaffoldings. BACKGROUND OF THE INVENTION Various types of motorized scaffoldings in which a working platform is guided along a tower for up and down movement and actuated to effect this movement are known. Examples of such motorized scaffoldings are found in the ST-GERMAIN U.S. Pat. No. 4,809,814 dated March 1989 and in my own previous U.S. Pat. No. 5,636,705 dated June 1997, and U.S. Pat. No. 5,368,125 dated November 1994. However, when for instance doing brick work on a building such as an apartment building provided with outwardly protruding balconies or the like, the scaffolding must be installed so that the work platform which only moves in up and down movement clears all the balconies. To reach the wall between the balconies, it is necessary to manually install an extension platform on the work platform which extends towards the building wall between the balconies. Obviously, this extension platform has to be installed and then removed at each balcony to clear the same. This is a time consuming and sometimes dangerous operation due to the height at which this work is performed. OBJECTS OF THE INVENTION It is therefore the main object of the present invention to provide a motorized scaffolding in which the above noted inconvenient and disadvantage is overcome. Another object of the present invention is to provide a motorized scaffolding in which the work platform can be shifted towards and away from the wall along which the scaffolding is installed. Another object of the present invention is to provide a motorized scaffolding in which simple means are provided to effect the above noted shifting movement of the work platform. SUMMARY OF THE INVENTION In a scaffolding comprising a tower, a plurality of vertically distant anchors to spacedly secure said tower to a wall, a sleeve partially surrounding said tower, driven and guided for up and down movement along the same, a work platform extending generally parallel to said wall supported by said sleeve not only for up and down movement along said tower but also for horizontal shifting movement transversely of said tower towards and away from said wall, and an actuator supported by said sleeve and acting on said work platform to effect said shifting movement. In a scaffolding further including a support frame releasably secured to said sleeve in vertical position and normal to said wall, a shiftable frame moveably supported by and parallel to said support frame, said work platform releasably secured to said shiftable frame at one end, said actuator carried by said support frame and acting on said work platform through the intermediary of said shiftable frame. In a scaffolding further including first and second similar upwardly directed hooks respectively secured to said sleeve and to said shiftable frame, said support frame releasably supported by said first hooks and said platform releasably supported by said second hooks and capable of being directly releasably supported by said first hooks in the absence of said support frame, said actuator and said shiftable frame. In a scaffolding further including rollers carried by said support frame and rollably supporting said shifting frame. In a scaffolding wherein said actuator includes an endless screw rotatably mounted on said support frame with its rotation axis parallel to the shifting direction of said shiftable frame, reversible motors to rotate said screw in opposite directions and equally spaced endless screw engaging members secured to said shiftable frame. In a scaffolding wherein said actuator includes a double acting hydraulic ram for shifting said shiftable frame between two shifted limit positions. In a scaffolding further including rollers carried by said support frame and rollably supporting said shiftable frame. In a scaffolding wherein said actuator includes and endless screw rotatably mounted on said support frame with its rotation axis parallel to the shifting direction of said shiftable frame, reversible motors to rotate said screw in opposite directions and equally spaced endless screw engaging members secured to said shiftable frame. In a scaffolding wherein said actuator includes a double acting hydraulic ram for shifting said shiftable frame between two shifted limit positions. In a scaffolding further including an abutment secured to said support frame and stops secured to said shiftable frame and selectively engaging said abutment when said shiftable frame reaches one or the other of its two shifted limit positions. In a scaffolding wherein said two limit positions are substantially equally distant from an intermediate position wherein said shiftable frame is substantially centered relative to said support frame and to said tower. In a scaffolding wherein said two limit positions are substantially equally distant from an intermediate position wherein said shiftable frame is substantially centered relative to said support frame and to said tower. In a scaffolding further including a second tower, an additional plurality of vertically spaced anchors to spacedly secure said second tower to said wall in a spaced position along said wall relative to said first claimed tower, a second sleeve partially surrounding said second tower driven and guided for up and down movement along said second tower, said work platform extending horizontally between said two sleeves and supported by the same at both its ends not only for up and down movement along both towers but also for horizontal shifting movements transversely of both towers towards and away from said wall and an actuator supported by each sleeve and acting on the related end of said work platform to effect said shifting movement. In a scaffolding further including a support frame releasably secured to each of said sleeves in vertical position and normal to said wall, a shiftable frame supported by and parallel to each support frame and work platform releasably secured at both ends to the respective shiftable frames, said actuators carried by said support frames and acting on the respective ends of said support platform through the intermediary of said shiftable frames. BRIEF DESCRIPTION OF THE DRAWINGS In the annexed drawings, like reference characters indicate like elements throughout. FIG. 1 is a partial elevation of two towers provided with the shifting system of the invention and supporting superposed work platforms; FIG. 2 is a partial plan section taken along line 2--2 of FIG. 1; FIG. 3 is a partial elevation taken along line 3--3 of FIG. 1; FIG. 4 is a vertical section taken in area 4 of FIG. 1; FIG. 5 is a partial plan section taken along line 5--5 of FIG. 4; FIG. 6 is a section taken along line 6--6 of FIG. 5; FIG. 7 is an elevation taken along line 7--7 of FIG. 6; FIG. 8 is a plan section taken along line 8--8 of FIG. 4; FIG. 9 is a right elevation view of the embodiment of FIG. 4; FIG. 10 is a view similar to that of FIG. 5 but showing an alternate embodiment of the actuator; FIG. 11 is a partial section taken along line 11--11 of FIG. 10; and FIG. 12 is a view similar to that of FIG. 9 but showing the alternate embodiment represented in FIG. 10. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring to FIGS. 1 and 2, there are shown two towers 20 supported on the ground by bases (not shown) and each attached to a building wall W by means of vertically spaced wall anchors 24. The towers 20 are of square cross-section and the two towers 20 are equally spaced from the wall W and at a certain distance from each other, for instance one hundred feet. A sleeve member 26 partially surrounds each tower 20 and is vertically guided for up and down movement along the tower 20 by means of rollers such as 28 in FIG. 2. The wall anchors 24 are cleared by the sleeve members 26 during their up and down movement. These sleeve members are guided along the respective towers by rollers 28. Any work platform raising system 22 can be used such as the one described in U.S. Pat. No. 5,636,705. Preferably, each sleeve 26 has a certain height so as to support two work platforms 30 in superposed position as shown in FIG. 1. These work platforms 30 are supported at each end by the respective sleeve 6. The motorized raising system 22 includes a gasoline engine 32 driving a hydraulic pump 34 mounted on a shelf 36 secured to each sleeve 26. Obviously, an electric driving system could be provided. A pair of hooks 38 are secured to each side of the sleeve 26 and at its top and lower ends of the same. These hooks 38 normally serve to removable support the two ends of the work platform 30 in accordance with the invention. A support frame 40 is hooked onto hooks 38, this frame 40 is of generally rectangular shape and is supported horizontally across a tower 20 and normal to the wall W. The hooks 38 engage the upper longitudinal member 42 of the support frame 40 while pins 44 extend from the lower horizontal member 46 of the support frame 40 to engage the hole of ears 48 secured to the sleeve 26. Brackets 50 are secured to the support frame 40 and rotatably support a horizontally extending endless screw 52 which is rotated two opposite directions by reversible hydraulic motors 54 carried by the brackets 50 and driving the shaft of the endless screw 52 at both ends thereof as shown in FIG. 5. Hydraulic motors 54 are controlled by suitable valves and supplied by the hydraulic pump 34 mounted on shelf 36. Brackets 56 are also secured to support frame 40 and support vertical rollers 58 and horizontal rollers 60 which support and guide a shiftable frame 62 which is of generally rectangular shape and mounted for movement towards and away from wall W in a shifting movement parallel to support frame 40. The shiftable frame 62 has top and bottom longitudinal members 64 and 66 respectively which are C-Shaped and L-shaped respectively forming two flanges engaged by the vertical rollers 58 and horizontal rollers 60. Members 64 and 66 are reinforced by cross bars 68 as shown in FIG. 9. Shiftable frame 62 is provided on its outside with platform engaging hooks 70 which are similar to the hooks 38 carried by the sleeve 26. Therefore the ends of each work platform 30 can be selectively supported either directly on the hooks 38 of sleeve 26 when no shifting movement is desired or on the hooks 70 of shiftable frame 62 with its corresponding ears 71 when platform shifting is required. Shiftable frame 62 carries a horizontal bar 72 on which a series of equally spaced rollers 74 are mounted, these rollers at a distance equal to the pitch of the endless screw flange 52a. Rollers 74 are therefore arranged to effect the shifting movement of shiftable frame 62 upon rotation of the endless screw 52 in either direction. A stop 76 is carried by the support frame 40 centrally thereof and selectively engages either one of the abutment fingers 78 carried by the shiftable frame 62 in the two limit positions of said frame 62 and consequently of the work platform 30 hooked onto the same. The shifted limit positions in both directions of the work platform 30 are preferably equally distant from the tower center. Upon the abutment finger 78 being contacted by either one of the two stops 76, a microswitch will be operated or other system to stop movement of the endless screw 52. Preferably, a pedal operated safety system 92 (as shown in FIGS. 5, 6 and 7) is provided for the operator to allow for movement of the endless screw 52 and consequently the shifting movement of frame 62 whenever desired. Said safety system 92 needs to be operated, and held in that position, to allow movement of the endless screw 52. Said system 92 includes a pedal 94, mounted at one end of a supporting bar 96, when pushed down by an operator, make the supporting bar 96 to rotate around pivot P1 at its approximate center and mounted on the sleeve member 26 thus raising a vertical bar 98 rotatably mounted at the other end of the supporting bar 96. The vertical bar 98 is guided by a guiding bar 100 parallel to the supporting bar 96 and also rotatably mounted on the sleeve member 26. The bottom end of the vertical bar 98 is adapted to be releasably engaged by one end or a horizontal bar 102 rotatably secured at its approximate center to the support frame 40 at pivot P2. The other end of the horizontal bar 102 includes a tooth 104 that engages two adjacent teeth of a gear 106 secured to the shaft of the endless screw 52. A first spring 108 biases the horizontal bar 102 such that it is kept in the gear engaging position so as to prevent rotation of the endless screw 52. At the other end of the safety system 92, there is a second spring 110 biasing the supporting bar 96 against a stopper 112 when it is not activated by the operator. This stopper 112 ensures a proper position of the vertical bar 98 for engagement of the end of the horizontal bar 102 when the support frame 40 is being mounted on the sleeve member 26. The actuator, including the endless screw 52, the hydraulic motors 54 and the driven rollers 74 can be replaced if desired by a hydraulic ram such as shown in FIGS. 10 and 11, the ram 80 is in the form of a reversible hydraulic cyclinder and piston unit, the cylinder 82 is carried by support frame 40 by means of brackets 84 while the piston rod 86 is attached by a cross pin 88 to ears 90 secured to shiftable frame 62. Limit positions of the piston rod 86 serves to replace the arrangement of the stops 76 and abutment fingers 78 of the previous embodiment. In this embodiment, the safety system 92 is not required. It will be noted that the work platform 30 can be shifted towards or away from the wall W and amount to three or four feet from its centered position with respect to the towers 20. It follows that when the scaffolding is installed, the towers 20 can be arranged at such a distance from the wall W that normally the work platform 30, when centered, would not clear balconies B protruding from the wall W as shown in FIG. 2. With the shifting arrangement of the invention, the work platform 30 can be laterally shifted to enable the bricklayers to be close to the wall W before and after clearing the balconies B. Clearance of these balconies B is achieved by outwardly shifting the work platform 30. In the drawings, a work platform 30 is suspended at each end by the shifting system of the invention but obviously a work platform 30 can be supported in overhang position by only one shifting system at one end provided the platform 30 is short enough.

In a scaffolding at least one tower anchor to secure the tower to a wall, a sleeve surrounding the tower and guided for up and down movement along the same, a support frame releasably secured to the sleeve in vertical position and normal to the wall, a shiftable frame moveably supported by and parallel to the support frame, replace ("the wall supported by the sleeve not ",) by and releasably secured to the shiftable frame at one end a work platform parallel to for horizontal shifting movement transversely of the tower towards and away from the wall and an actuator carried by the support frame and acting on the work platform through the intermediary of the shiftable frame to effect said shifting movement.

CROSS-REFERENCE TO RELATED APPLICATIONS [0001] This application is a continuation of U.S. application Ser. No. 15/408,695 filed on Jan. 18, 2017, which is a continuation of U.S. application Ser. No. 14/354,819 filed on Apr. 28, 2014, which claims the benefit of National Stage application of International Application No. PCT/KR2012/011059, filed on Dec. 18, 2012, which claims the benefit of priority of Korean Patent Application No. 10-2011-0140861 filed on Dec. 23, 2011, Korean Patent Application No. 10-2012-0003617 filed on Jan. 11, 2012, and Korean Patent Application No. 10-2012-0147996 filed on Dec. 18, 2012, the entire disclosures of which are incorporated herein by reference for all purposes. BACKGROUND OF THE INVENTION [0002] Field of the Invention [0003] The present invention relates to an image processing method and apparatus and, more particularly, to an inter-frame prediction method and an apparatus using the method. [0004] Related Art [0005] A demand for images having high resolution and high quality, such as a High Definition (HD) image and an Ultra High Definition (UHD) image, is recently increasing in a variety of application fields. As the resolution and quality of image data become higher, the amount of the image data becomes relatively greater than that of the existing image data. For this reason, if the image data is transmitted using media, such as the existing wired/wireless broadband lines, or the image data is stored by using the existing storage medium, a transmission cost and a storage cost are increased. Image compression techniques with high efficiency can be used to solve the problems occurring as the resolution and quality of image data becomes higher. [0006] Image compression techniques include a variety of techniques, such as an inter-frame prediction technique for predicting a pixel value included in a current picture from a picture anterior or posterior to the current picture, an intra-frame prediction technique for predicting a pixel value included in a current picture by using information on a pixel within the current picture, and an entropy coding technique for allocating a short symbol to a value having high frequency of appearance and allocating a long symbol to a value having low frequency of appearance. Image data can be effectively compressed, transmitted, or stored by using the image compression techniques. SUMMARY OF THE INVENTION [0007] An object of the present invention is to provide a method of setting the reference picture index of a temporal merging candidate. [0008] Another object of the present invention is to provide an apparatus for performing a method of setting the reference picture index of a temporal merging candidate. [0009] In accordance with an aspect of the present invention, an inter-frame prediction method using a temporal merging candidate may include the steps of determining the reference picture index of the temporal merging candidate for a current block and deriving the temporal merging candidate block of the current block and deriving the temporal merging candidate from the temporal merging candidate block, wherein the reference picture index of the temporal merging candidate can be derived irrespective of whether other blocks except the current block have been decoded or not. The temporal merging candidate may be derived in a unit of a coding block including the current block or in a unit of the current block depending on whether the current block will use a single merging candidate list or not. The inter-frame prediction method may further include the step of determining whether or not the current block is a block using the single merging candidate list, wherein the single merging candidate list may derive and generate at least one of the spatial merging candidate and the temporal merging candidate of a prediction block based on a coding block including the prediction block. The step of determining whether or not the current block is a block using the single merging candidate list may include the steps of decoding information on the size of the current block and determining whether or not the information on the size of the current block satisfies conditions of the size of a block that the single merging candidate list is derived. The reference picture index of the temporal merging candidate may be set to a fixed value. The temporal merging candidate may include a temporal motion vector calculated by comparing a difference between the reference picture index of a temporal merging candidate block (i.e., a colocated block) and the index of a picture (i.e., a colocated picture) including the colocated block with a difference between the reference picture index of the temporal merging candidate having the index of the fixed value and the index of the picture including the current block. The reference picture index of the temporal merging candidate may be set to 0. [0010] In accordance with another aspect of the present invention, a decoder for performing an inter-frame prediction method using a temporal merging candidate includes a merging candidate deriving unit configured to determine the reference picture index of the temporal merging candidate for a current block, derive the temporal merging candidate block of the current block, and derive a temporal merging candidate from the temporal merging candidate block, wherein the reference picture index of the temporal merging candidate may be derived irrespective of whether other blocks except the current block have been decoded or not. The temporal merging candidate may be derived in a unit of a coding block including the current block or in a unit of the current block depending on whether the current block will use a single merging candidate list or not. The merging candidate deriving unit may be configured to determine whether or not the current block is a block using the single merging candidate list, and the single merging candidate list may derive and generate at least one of the spatial merging candidate and the temporal merging candidate of a prediction block based on a coding block including the prediction block. The merging candidate deriving unit may be configured to decode information on the size of the current block and determine whether or not the information on the size of the current block satisfies conditions of the size of a block that the single merging candidate list is derived, in order to determine whether or not the current block is a block using the single merging candidate list. The reference picture index of the temporal merging candidate may be set to a fixed value. The temporal merging candidate may include a temporal motion vector calculated by comparing a difference between the reference picture index of a temporal merging candidate block (a colocated block) and the index of a picture (a colocated picture) including the colocated block with a difference between the reference picture index of the temporal merging candidate having the index of the fixed value and the index of the picture including the current block. The reference picture index of the temporal merging candidate may be set to 0. [0011] As described above, in accordance with the method and apparatus for setting the reference picture index of a temporal merging candidate according to embodiments of the present invention, inter-frame prediction using a temporal merging candidate can be performed on a plurality of prediction blocks in parallel by using a temporal merging candidate set to a specific value or using the reference picture index of a spatial merging candidate at a predetermined location as the reference picture index of a temporal merging candidate. Accordingly, an image processing speed can be increased, and the complexity of image processing can be reduced. BRIEF DESCRIPTION OF THE DRAWINGS [0012] FIG. 1 is a block diagram showing the construction of an image coder in accordance with an embodiment of the present invention. [0013] FIG. 2 is a block diagram showing the construction of an image decoder in accordance with another embodiment of the present invention. [0014] FIG. 3 is a conceptual diagram illustrating an inter-frame prediction method using merge mode in accordance with an embodiment of the present invention. [0015] FIG. 4 is a conceptual diagram illustrating inter-frame prediction using a temporal merging candidate and the reference picture index of the temporal merging candidate in accordance with an embodiment of the present invention. [0016] FIG. 5 is a conceptual diagram illustrating a case where one coding block is partitioned into two prediction blocks. [0017] FIG. 6 is a conceptual diagram illustrating a method of setting the reference picture index of a temporal merging candidate in accordance with an embodiment of the present invention. [0018] FIG. 7 is a conceptual diagram illustrating a method of deriving the reference picture indices of temporal merging candidates in accordance with an embodiment of the present invention. [0019] FIG. 8 is a conceptual diagram illustrating a method of deriving the reference picture indices of temporal merging candidates in accordance with an embodiment of the present invention. [0020] FIG. 9 is a conceptual diagram illustrating a method of deriving the reference picture indices of temporal merging candidates in accordance with an embodiment of the present invention. [0021] FIG. 10 is a conceptual diagram illustrating a method of deriving the reference picture indices of temporal merging candidates in accordance with an embodiment of the present invention. [0022] FIG. 11 is a conceptual diagram illustrating a method of deriving the reference picture index of a temporal merging candidate in accordance with an embodiment of the present invention. [0023] FIG. 12 is a conceptual diagram illustrating a method of deriving the reference picture index of a temporal merging candidate in accordance with an embodiment of the present invention. [0024] FIG. 13 is a conceptual diagram illustrating a method of deriving the reference picture index of a temporal merging candidate in accordance with an embodiment of the present invention. [0025] FIG. 14 is a flowchart illustrating a method of including a temporal merging candidate in a merging candidate list in accordance with an embodiment of the present invention. [0026] FIG. 15 is a conceptual diagram illustrating a method of generating a single merging candidate list by sharing all spatial merging candidates and temporal merging candidates in a plurality of prediction blocks in accordance with an embodiment of the present invention. [0027] FIG. 16 is a conceptual diagram illustrating a method of generating a single candidate list in accordance with an embodiment of the present invention. DESCRIPTION OF EXEMPLARY EMBODIMENTS [0028] Hereinafter, exemplary embodiments are described in detail with reference to the accompanying drawings. In describing the embodiments of the present invention, a detailed description of the known functions and constructions will be omitted if it is deemed to make the gist of the present invention unnecessarily vague. [0029] When it is said that one element is “connected” or “coupled” to the other element, the one element may be directly connected or coupled to the other element, but it should be understood that a third element may exist between the two elements. Furthermore, in the present invention, the contents describing that a specific element is “included (or comprised)” does not mean that elements other than the specific element are excluded, but means that additional elements may be included in the implementation of the present invention or in the scope of technical spirit of the present invention. [0030] Terms, such as the first and the second, may be used to describe various elements, but the elements should not be restricted by the terms. The terms are used to only distinguish one element and the other element from each other. For example, a first element may be named a second element without departing from the scope of the present invention. Likewise, a second element may also be named a first element. [0031] Furthermore, elements described in the embodiments of the present invention are independently shown in order to indicate different and characteristic functions, and it does not mean that each of the elements consists of separate hardware or a piece of software unit. That is, the elements are arranged, for convenience of description, and at least two of the elements may be combined to form one element or one element may be divided into a plurality of elements and the plurality of elements may perform functions. An embodiment in which the elements are combined or each of the elements is divided is included in the scope of the present invention without departing from the essence of the present invention. [0032] Furthermore, in the present invention, some elements may not be essential elements for performing essential functions, but may be optional elements for improving only performance. The present invention may be implemented using only the essential elements for implementing the essence of the present invention other than the elements used to improve only performance, and a structure including only the essential elements other than the optional elements used to improve only performance are included in the scope of the present invention. [0033] FIG. 1 is a block diagram showing the construction of an image coder in accordance with an embodiment of the present invention. [0034] Referring to FIG. 1 , the image coder 100 includes a motion prediction unit 111 , a motion compensation unit 112 , an intra-prediction unit 120 , a switch 115 , a subtractor 125 , a transform unit 130 , a quantization unit 140 , an entropy coding unit 150 , an inverse quantization unit 160 , an inverse transform unit 170 , an adder 175 , a filtering unit 180 , and a reference picture buffer 190 . [0035] The image coder 100 can perform coding an input picture in intra mode or inter mode and output a bit stream. The switch 115 can switch to intra mode in the case of intra mode and can switch to inter mode in the case of inter mode. The image coder 100 can derive a prediction block for the input block of the input picture and then code the residual of the input block and the prediction block. [0036] Intra mode can be defined and used as a term ‘intra-frame prediction mode’, inter mode can be defined and used as a term ‘inter-frame prediction mode’, the intra-prediction unit 120 can be defined and used as a term ‘intra-frame prediction unit’, and the motion prediction unit 111 and the motion compensation unit 112 can be defined and used as a term ‘inter-frame prediction unit’. [0037] An inter-frame prediction method in accordance with an embodiment of the present invention discloses a method of determining the reference picture index of a temporal merging candidate. The intra-prediction unit 120 can include a merging candidate deriving unit for deriving the spatial merging candidate and temporal merging candidate blocks of a current block and deriving a spatial merging symbol from the spatial merging candidate block and a temporal merging candidate from the temporal merging candidate block. A method of deriving the merging candidates will be described in detail later. [0038] In the case of intra mode, the intra-prediction unit 120 can derive the prediction block by performing spatial prediction by using the pixel value of an already coded block near a current block. [0039] In the case of inter mode, the motion prediction unit 111 can obtain a motion vector by searching a reference picture, stored in the reference picture buffer 190 , for a region that is most well matched with the input block in a motion prediction process. The motion compensation unit 112 can derive the prediction block by performing motion compensation using the motion vector. [0040] The subtractor 125 can derive a residual block by way of the residual of the input block and the derived prediction block. The transform unit 130 can output a transform coefficient by performing transform on the residual block. Here, the transform coefficient can mean a coefficient value derived by performing transform on the residual block and/or a residual signal. In the following specification, a quantized transform coefficient level derived by applying quantization to a transform coefficient can also be called a transform coefficient. [0041] The quantization unit 140 can quantize the input transform coefficient according to a quantization parameter and output a quantized transform coefficient level. [0042] The entropy coding unit 150 can perform entropy coding based on values calculated by the quantization unit 140 or a coding parameter value derived in a coding process and output a bit stream based on a result of the entropy coding. [0043] If entropy coding is applied, the size of a bit stream for each of target coding symbols can be reduced because the symbols are represented by allocating a small number of bits to a symbol having a high probability of occurrence and a large number of bits to a symbol having a low probability of occurrence. Accordingly, the compression performance of image coding can be increased by way of the entropy coding. The entropy coding unit 150 can use a coding method, such as exponential golomb, Context-Adaptive Variable Length Coding (CAVLC), or Context-Adaptive Binary Arithmetic Coding (CABAC), for the entropy coding. [0044] In the image coder according to the embodiment of FIG. 1 , a currently coded image needs to be decoded and stored in order to be used as a reference picture because inter-prediction coding, that is, inter-frame prediction coding, is performed. Accordingly, the quantized coefficient is inversely quantized by the inverse quantization unit 160 and then inversely transformed by the inverse transform unit 170 . The inversely quantized and inversely transformed coefficient is added to the prediction block by way of the adder 175 , and thus a reconstructed block is derived. [0045] The reconstructed block experiences the filtering unit 180 . The filtering unit 180 can apply one or more of a deblocking filter, a Sample Adaptive Offset (SAO), and an Adaptive Loop Filter (ALF) to the reconstructed block or a reconstructed picture. The reconstructed block that has experienced the filtering unit 180 can be stored in the reference picture buffer 190 . [0046] FIG. 2 is a block diagram showing the construction of an image decoder in accordance with another embodiment of the present invention. [0047] Referring to FIG. 2 , the image decoder 200 includes an entropy decoding unit 210 , an inverse quantization unit 220 , an inverse transform unit 230 , an intra-prediction unit 240 , a motion compensation unit 250 , an adder 255 , a filtering unit 260 , and a reference picture buffer 270 . [0048] The image decoder 200 can receive a bit stream from a coder, perform decoding on the bit stream in intra mode or inter mode, and output a reconfigured image, that is, a reconstructed picture. A switch can switch to intra mode in the case of intra mode and can switch to inter mode in the case of inter mode. The image decoder 200 can obtain a reconstructed residual block from the input bit stream, derive a prediction block from the reconstructed residual block, and derive a block reconstructed by adding the reconstructed residual block and the prediction block together, that is, the reconstructed block. [0049] The entropy decoding unit 210 can derive symbols, including a symbol having a quantized coefficient form, by performing entropy decoding on the input bit stream according to a probability distribution. The entropy decoding method is similar to the aforementioned entropy coding method. [0050] If the entropy decoding method is applied, the size of a bit stream for each of symbols can be reduced because the symbols are represented by allocating a small number of bits to a symbol having a high probability of occurrence and a large number of bits to a symbol having a low probability of occurrence. Accordingly, the compression performance of image decoding can be increased by the entropy decoding method. [0051] The quantized coefficient is inversely quantized by the inverse quantization unit 220 and then inversely transformed by the inverse transform unit 230 . As a result of the inverse quantization and the inverse transform on the quantized coefficient, the reconstructed residual block can be derived. [0052] In the case of intra mode, the intra-prediction unit 240 can derive a prediction block by performing spatial prediction using the pixel value of an already decoded block near a current block. In the case of inter mode, the motion compensation unit 250 can derive the prediction block by performing motion compensation using a motion vector and a reference picture stored in the reference picture buffer 270 . [0053] An inter-frame prediction method in accordance with an embodiment of the present invention discloses a method of determining the reference picture index of a temporal merging candidate. An intra-prediction unit can include a merging candidate deriving unit for deriving the spatial merging candidate and temporal merging candidate blocks of a current block and deriving a spatial merging symbol from the spatial merging candidate block and a temporal merging candidate from the temporal merging candidate block. A method of deriving the merging candidates will be additionally described later. [0054] The reconstructed residual block and the prediction block are added by the adder 255 , and the added block can experience the filtering unit 260 . The filtering unit 260 can apply one or more of a deblocking filter, an SAO, and an ALF to a reconstructed block or a reconstructed picture. The filtering unit 260 can output the reconfigured picture. The reconstructed picture can be stored in the reference picture buffer 270 and used for inter-prediction. [0055] A method of improving the prediction performance of an image coder and an image decoder includes a method of increasing the accuracy of an interpolation image and a method of predicting a difference signal. The difference signal indicates a difference between the original image and a prediction image. In the present invention, a “difference signal” can be replaced with a “residual signal”, a “residual block”, or a “difference block” depending on context. A person having ordinary skill in the art can distinguish the residual signal, the residual block, and the difference block from each other within a range that does not affect the spirit and essence of the invention. [0056] In an embodiment of the present invention, a term, such as a Coding Unit (CU), a Prediction Unit (PU), or a Transform Unit (TU), can be used as a unit for processing an image. [0057] The CU is an image processing unit on which coding/decoding are performed. The CU can include information used to code or decode a coding block, that is, a block unit set of luminance samples or chrominance samples on which coding/decoding are performed, and the samples of the coding block. [0058] The PU is an image processing unit on which prediction is performed. The PU can include information used to predict a prediction block, that is, a block unit set of luminance samples or chrominance samples on which prediction is performed, and the samples of the prediction block. Here, a coding block can be classified into a plurality of prediction blocks. [0059] The TU is an image processing unit on which transform is performed. The TU can include information used to transform a transform block, that is, a block unit set of luminance samples or chrominance samples on which transform is performed, and the samples of the transform block. Here, a coding block can be classified into a plurality of transform blocks. [0060] In an embodiment of the present invention, a block and a unit can be interpreted as having the same meaning unless described otherwise hereinafter. [0061] Furthermore, a current block can designate a block on which specific image processing is being performed, such as a prediction block on which prediction is now performed or a coding block on which prediction is now performed. For example, if one coding block is partitioned into two prediction blocks, a block on which prediction is now performed, from among the partitioned prediction blocks, can be designated as a current block. [0062] In an embodiment of the present invention, an image coding method and an image decoding method to be described later can be performed by the elements of the image coder and image decoder described with reference to FIGS. 1 and 2 . The element can include not only a hardware meaning, but also a software processing unit that can be performed by an algorithm. [0063] Hereinafter, a method of setting the reference picture index of a temporal merging candidate disclosed in an embodiment of the present invention can be used both in SKIP mode in an image processing method and merge mode, that is, one of modes, in an inter-frame prediction method. SKIP mode is an image processing method of outputting a block, predicted based on motion prediction information derived from surrounding blocks, as a reconstructed block without generating a residual block. Merge mode, that is, one of modes, in an inter-frame prediction method is an image processing method which is the same as SKIP mode in that a block is predicted based on motion prediction information derived from surrounding blocks, but is different from SKIP mode in that a block reconstructed by adding a residual block and a prediction block by coding and decoding information on the residual block is outputted. Intra-loop filtering methods, such as deblocking filtering and a sample adaptive offset, can be additionally applied to the outputted reconstructed block. [0064] FIG. 3 is a conceptual diagram illustrating an inter-frame prediction method using merge mode in accordance with an embodiment of the present invention. [0065] Referring to FIG. 3 , the inter-frame prediction using merge mode can be performed as follows. [0066] The inter-frame prediction method using merge mode refers to a method of deriving a merging candidate from a block neighboring a current block and performing inter-frame prediction by using the derived merging candidate. The neighboring block used to derive the merging candidate can be partitioned into a block which is located in the same picture as a current block and neighbors the current block and a block which is located in a picture different from a picture including a current block and at a location collocated with the current block. [0067] Hereinafter, in an embodiment of the present invention, from among neighboring blocks used to derive a merging candidate, a block which is located in the same picture as a current block and neighbors the current block is defined as a spatial merging candidate block, and motion prediction-related information derived from the spatial merging candidate block is defined as a spatial merging candidate. Furthermore, from among neighboring blocks used to derive a merging candidate, a block which is located in a picture different from a picture including a current block and at a location collocated with the current block is defined as a temporal merging candidate block, and motion prediction-related information derived from the temporal merging candidate block is defined as a temporal merging candidate [0068] That is, the inter-frame prediction method using merge mode is an inter-frame prediction method for predicting a current block by using motion prediction-related information (i.e., a spatial merging candidate) on a spatial merging candidate block or motion prediction-related information (i.e., a temporal merging candidate) on a temporal merging candidate block to be described later. [0069] For example, motion vectors mvL0/L1, reference picture indices refIdxL0/L1, and pieces of reference picture list utilization information predFlagL0/L1 can be used as the motion prediction-related information. [0070] FIG. 3(A) shows the motion vectors mvL0/L1, the reference picture indices refIdxL0/L1, and the pieces of reference picture list utilization information predFlagL0/L1. [0071] A motion vector 304 is directional information and can be used for a prediction block to derive information on a pixel, located at a specific location, from a reference picture in performing inter-frame prediction. If inter-frame prediction is performed using a plurality of pieces of directional information in a prediction block, motion vectors for respective directions can be indicated by mvL0/L1. [0072] A reference picture index 306 is information on the index of a picture to which a prediction block refers in performing inter-frame prediction. If inter-frame prediction is performed using a plurality of reference pictures, reference pictures can be indexed using respective reference picture indices refIdxL0 and refIdxL1. [0073] The reference picture list utilization information can indicate that a reference picture has been derived from what reference picture list 0 308 . For example, pictures i, j, and k can be stored in a reference picture list 0 308 and used. If there are two lists in which a reference picture is stored, information on that the reference picture has been derived from what reference picture list can be indicated by predFlagL0 and predFlagL1. [0074] In order to perform the inter-frame prediction method using merge mode, first, a spatial merging candidate can be obtained through the following step (1). FIG. 3(B) discloses a spatial merging candidate and a temporal merging candidate. [0075] (1) A Spatial Merging Candidate is Derived from Neighboring Blocks for a Current block (i.e., a target prediction block). [0076] As described above, a spatial merging candidate is motion prediction-related information derived from a spatial merging candidate block. The spatial merging candidate block can be derived on the basis of the location of a current block. [0077] Referring to FIG. 3(B) , the existing spatial merging candidate blocks 300 , 310 , 320 , 330 , and 340 have been derived based on a target prediction block. It is assumed that the location of a pixel present at an upper left end of the target prediction block is (xP, yP), the width of a prediction block is nPbW, the height of the target prediction block is nPbH, and MinPbSize is the smallest size of the prediction block. In an embodiment of the present invention hereinafter, the spatial merging candidate blocks of the prediction block can include a block including a pixel present at (xP−1, yP+nPbH), that is, a first block (or an A0 block) 300 on the left side, a block including a pixel present at (xP−1, yP+nPbH−1), that is, a second block (or an A1 block) 310 on the left side, a block including a pixel present at (xP+nPbW, yP−1), that is, a first block (or a B0 block) 320 at the upper end, a block including a pixel present at (xP+nPbW−1, yP−1), that is, a second block (or a B1 block) 330 at the upper end, and a block including a pixel present at (xP−1, yP−1), that is, a third block (or a B2 block) 340 at the upper end. Another value, for example, “MinPbSize” may be used instead of 1. In this case, a block at the same location can be indicated. Coordinates used to indicate the block at the specific location are arbitrary, and the block at the same location may be indicated by various other representation methods. [0078] The locations of the spatial merging candidate blocks 300 , 310 , 320 , 330 , and 340 and the number thereof and the locations of the temporal merging candidate blocks 360 and 370 and the number thereof disclosed in FIG. 3 are illustrative, and the locations of spatial merging candidate blocks and the number thereof and the locations of temporal merging candidate blocks and the number thereof can be changed if they fall within the essence of the present invention. Furthermore, order of merging candidate blocks preferentially scanned when a merging candidate list is configured may be changed. That is, the locations of candidate prediction blocks, the number thereof, and a scan order thereof, and a candidate prediction group used when a candidate prediction motion vector list is configured, described in the following embodiment of the present invention, are only illustrative and can be change if they fall within the essence of the present invention. [0079] A spatial merging candidate can be derived from an available spatial merging candidate block by determining whether the spatial merging candidate blocks 300 , 310 , 320 , 330 , and 340 are available or not. Information indicating whether a spatial merging candidate can be derived from a spatial merging candidate block or not is availability information. For example, if a spatial merging candidate block is located outside a slice, tile, or a picture to which a current block belongs or is a block on which intra-frame prediction has been performed, a spatial merging candidate, that is, motion prediction-related information, cannot be derived from the corresponding block. In this case, the spatial merging candidate block can be determined to be not available. In order to determine availability information on the spatial merging candidate, some determination methods can be used and embodiments thereof are described in detail later. [0080] If a spatial merging candidate block is available, motion prediction-related information can be derived and used to perform inter-frame prediction using merge mode on a current block. [0081] One coding block can be partitioned into one or more prediction blocks. That is, a coding block can include one or more prediction blocks. If a plurality of prediction blocks is included in a coding block, each of the prediction blocks can be indicated by specific index information. For example, if one coding block is partitioned into two prediction blocks, the two prediction blocks can be indicated by setting the partition index of one prediction block to 0 and the partition index of the other prediction block to 1. If a partition index is 0, a prediction block may be defined as another term, such as a first prediction block. If a partition index is 1, a prediction block may be defined as another term, such as a second prediction block. If one coding block is further partitioned into additional prediction blocks, index values indicative of the prediction blocks can be increased. The terms defined to designate the prediction blocks are arbitrary, and the terms may be differently used or differently interpreted. The partition index of a prediction block may also be used as information indicative of order that image processing, such as coding and decoding, is performed when a prediction block performs the image processing. [0082] If a plurality of prediction blocks is present within one coding block, there may be a case where coding or decoding on another prediction block must be first performed when a spatial merging candidate for the prediction block is derived. In accordance with an embodiment of the present invention, a method of deriving spatial merging candidates and temporal merging candidates in parallel to each of prediction blocks included in one coding block when generating a merging candidate list is additionally disclosed in detail. [0083] (2) Determine the Reference Picture Index of a Temporal Merging Candidate. [0084] A temporal merging candidate is motion prediction-related information derived from a temporal merging candidate block that is present at a picture different from a picture including a current block. The temporal merging candidate block is derived based on a block that is at a location collocated based on the location of the current block. The term ‘colocated block’ can be used as the same meaning as the temporal merging candidate block. [0085] Referring back to FIG. 3 , the temporal merging candidate blocks 360 and 370 can include the block 360 including a pixel at a location (xP+nPSW, yP+nPSH) in the colocated picture of a current prediction block or the block 370 including a pixel at a location (xP+(nPSW>>1), yP+(nPSH>>1)) if the block 360 including the pixel at the location (xP+nPSW, yP+nPSH) is not available, on the basis of the pixel location (xP, yP) within the picture including the prediction block. The prediction block 360 including the pixel at the location (xP+nPSW, yP+nPSH) in the colocated picture can be called a first temporal merging candidate block (or a first colocated block) 360 , and the prediction block including the pixel at the location (xP+(nPSW>>1), yP+(nPSH>>1)) in the colocated picture can be called a second temporal merging candidate block 370 . [0086] Finally, the final temporal merging candidate block used to derive a temporal merging candidate (or motion prediction-related information) can be at a location partially moved on the basis of the locations of the first temporal merging candidate block 360 and the second temporal merging candidate block 370 . For example, if only pieces of motion prediction-related information on some prediction blocks present in a colocated picture are stored in memory, a block at a location partially moved on the basis of the locations of the first temporal merging candidate block 360 and the second temporal merging candidate block 370 can be used as the final temporal merging candidate block for deriving the final motion prediction-related information. Like in a spatial merging candidate block, the location of a temporal merging candidate block can be changed or added unlike in FIG. 3 , and an embodiment thereof is described later. [0087] The reference picture index of a temporal merging candidate is information indicative of a picture that is referred in order for a current block to perform inter-frame predict on the basis of a motion vector mvLXCol derived from a temporal merging candidate. [0088] FIG. 4 is a conceptual diagram illustrating inter-frame prediction using a temporal merging candidate and the reference picture index of the temporal merging candidate in accordance with an embodiment of the present invention. [0089] Referring to FIG. 4 , a current block 400 , a picture 410 including the current block, a temporal merging candidate block (or a colocated block) 420 , and a colocated picture 430 including the colocated block can be defined. [0090] From a viewpoint of the temporal merging candidate block 420 , there is a picture 440 used in inter-frame prediction by the temporal merging candidate block in order to perform the inter-frame prediction on the temporal merging candidate block 420 . This picture is defined as the reference picture 440 of the colocated picture 430 . Furthermore, a motion vector that is used by the temporal merging candidate block 420 in order to perform inter-frame prediction from the reference picture 440 of the colocated picture 430 can be defined as mvCol 470 . [0091] From a standpoint of the current block 400 , a reference picture 460 used in the inter-frame prediction of the current block 400 on the basis of the calculated mvCol 470 has to be defined. The reference picture defined to be used in the inter-frame prediction of the current block 400 can be called the reference picture 460 of a temporal merging candidate. That is, the index of the reference picture 460 of the temporal merging candidate (i.e., the reference index of the temporal merging candidate) is a value indicative of a reference picture used in the temporal motion prediction of the current block 400 . At the step (2), the reference picture index of a temporal merging candidate can be determined. [0092] A mvCol 470 , that is, a motion vector derived from the temporal merging candidate block 420 , can be scaled and transformed into a different value depending on the distance between the colocated picture 430 and the reference picture 440 of the colocated picture and the distance between the picture 410 including the current block and the reference picture 460 of the temporal merging candidate derived through the step (2). [0093] That is, inter-frame prediction according to the temporal merging candidate of the current block 400 can be performed based on mvLXCol 480 derived through a step (3) to be described later, on the basis of the reference picture index 460 of the temporal merging candidate derived through the step (2) and the reference picture index 460 of the temporal merging candidate. mvLXCol can be defined as a temporal motion vector. [0094] In the existing image coding/decoding methods, the reference picture index of a temporal merging candidate can be determined based on the reference picture index candidate of a temporal merging candidate derived from the reference picture index of a spatial merging candidate in a target prediction block. If this method is used, there may be a case where the reference picture index of a spatial merging candidate that has not yet been coded or decoded must be derived. In this case, the reference picture index of the spatial merging candidate can be derived only when coding or decoding on a prediction block including the corresponding spatial merging candidate is finished. Accordingly, if the reference picture index of a temporal merging candidate is determined based on the reference picture index candidates of temporal merging candidates derived from all spatial merging candidate blocks, a process of deriving the reference pictures of the temporal merging candidates for a current block cannot be performed in parallel. FIG. 5 discloses this problem. [0095] FIG. 5 is a conceptual diagram illustrating a case where one coding block is partitioned into two prediction blocks. [0096] Referring to FIG. 5 , one coding block is partitioned into a first prediction block 500 and a second prediction block 520 having an N×2N form. Spatial merging candidate blocks for the first prediction block 500 are derived on the basis of the location of the first prediction block 500 as in FIG. 5(A) , and spatial merging candidate blocks for the second prediction block 520 are derived on the basis of the location of the second prediction block 520 as in FIG. 5(B) . Although not shown, in temporal merging candidate blocks, temporal merging candidates can be derived on the basis of the location of each of prediction blocks. [0097] The spatial merging candidate blocks of the first prediction block 500 are outside the first prediction block 500 and are at locations included in blocks on which coding or decoding has already been performed. [0098] In contrast, an A1 block 530 , from among the spatial merging candidate blocks of the second prediction block 520 , is present within the first prediction block 500 . Accordingly, after prediction on the first prediction block 500 is performed, motion prediction-related information (e.g., a motion vector, a reference picture index, and reference picture list utilization information) on the A1 block 530 can be known. Furthermore, the motion prediction-related information of the A0 block 550 cannot be derived because the A0 block 550 is at a location that has not yet been coded or decoded. [0099] If the reference picture index of a temporal merging candidate is derived from the motion prediction-related information of the A1 block 530 , it can be derived after coding and decoding on the first prediction block 500 are finished. Furthermore, the reference picture index cannot be derived from the A0 block 550 . That is, since the reference picture indices of some spatial merging candidate blocks cannot be derived, the reference picture indices of temporal merging candidates for respective prediction blocks cannot be derived in parallel. [0100] In an embodiment of the present invention, in order to solve the problem, methods of deriving the reference picture indices of temporal merging candidates (or the reference indices of temporal merging candidates) for prediction blocks are disclosed. [0101] If a method of deriving the reference picture indices of temporal merging candidates in accordance with an embodiment of the present invention is used, processes of deriving the reference picture indices of temporal merging candidates for some prediction blocks can be performed in parallel. Since the reference picture indices of temporal merging candidates are derived in parallel, inter-frame prediction processes using merge mode for a plurality of prediction blocks included in one coding block can be performed in parallel. [0102] Hereinafter, in an embodiment of the present invention, a method of deriving the reference picture index of a temporal merging candidate is disclosed and additionally described in detail. [0103] (3) Derive Motion Prediction-Related Information on a Temporal Merging Candidate Block. [0104] At the step (3), in order to perform motion prediction based on a temporal merging candidate, temporal merging candidates, such as information on whether a temporal merging candidate block is available or not (availableFlagCol), reference picture list utilization information (PredFlagLXCol), and information on the motion vector (mvLXCol) of a temporal merging candidate, can be derived. The motion prediction-related information derived from the temporal merging candidate can be defined as a term ‘temporal merging candidate’. The availability information on the temporal merging candidate block indicates whether a temporal merging candidate can be derived from the temporal merging candidate block or not. The temporal merging candidate can be included in a merging candidate list on the basis of the availability information on the temporal merging candidate block. [0105] (4) Derive a Merging Candidate List. [0106] A merging candidate list can include information on a merging candidate that can be used in inter-frame prediction using merge mode on the basis of availability information on a merging candidate block (i.e., a spatial merging candidate block or a temporal merging candidate block). One of merging candidates included in a merging candidate list can be used to perform inter-frame prediction using merge mode on a current block. Information on whether what merging candidate will be used to predict a current block (i.e., a merging index) can be coded in a coding step and transmitted to a decoder. [0107] A merging candidate list can be generated with the following order of priority. [0108] 1) If an A1 block is available, a merging candidate derived from the A1 block [0109] 2) If a B1 block is available, a merging candidate derived from the B1 block [0110] 3) If a B0 block is available, a merging candidate derived from the B0 block [0111] 4) If an A0 block is available, a merging candidate derived from the A0 block [0112] 5) If a B2 block is available, a merging candidate derived from the B2 block [0113] 6) If a Col block is available, a merging candidate derived from the Col block [0114] The merging candidate list can include, for example, 0 to 5 merging candidates depending on the number of available blocks. If the number of blocks used to derive a merging candidate is many, more merging candidates may be included in the merging candidate list. [0115] (5) If the number of merging candidates included in a merging candidate list is smaller than a maximum number of merging candidates that can be included in the merging candidate list, an additional merging candidate is derived. [0116] An additional merging candidate can be a candidate generated by combining pieces of motion prediction-related information on the existing merging candidates (i.e., a combined merging candidate) or can be a 0-vector merging candidate (i.e., a zero merging candidate) Here, the 0-vector merging candidate designates a merging candidate having a motion vector (0,0). [0117] (6) Determine a Merging Candidate Applied to Inter-Frame Prediction Performed on a Current Block, from Among Merging Candidates Included in a Merging Candidate List, and Set Motion Prediction-Related Information on the Determined Merging Candidate as Motion Prediction-Related Information on a Current Block. [0118] In a decoding process, inter-frame prediction using merge mode can be performed on a current block on the basis of a merging index merge_idx[xP][yP], that is, information on which one of candidates included in a merging candidate list is used in inter-frame prediction performed on the current block. [0119] Through a procedure of the step (1) to the step (6), motion prediction-related information on a current block can be derived and inter-frame prediction can be performed on the current block based on the derived motion prediction-related information. [0120] An embodiment of the present invention discloses a method of deriving the reference picture indices of temporal merging candidates for a plurality of prediction blocks, included in one coding block, in parallel in setting the reference picture index of a temporal merging candidate at the step (2) is disclosed. [0121] Various kinds of methods below can be used as the method of deriving the reference picture indices of temporal merging candidates for a plurality of prediction blocks, included in a coding block, in parallel. [0122] 1) A method of setting the location of a spatial merging candidate block, used to derive the reference picture index candidate of a temporal merging candidate for a target prediction block (i.e., a current block), as a location at which a coding block including the current block is located and on which coding or decoding has already been performed. [0123] 2) A method of, if the location of a spatial merging candidate block used to derive the reference picture index candidate of a temporal merging candidate for a target prediction block (i.e., a current block) is within a coding block or a location on which coding has not yet been performed, setting the reference picture index candidate of a temporal merging candidate derived from a spatial merging candidate at the corresponding location to ‘0’. [0124] 3) A method of setting the reference picture index of the temporal merging candidate of a target prediction block (i.e., a current block) to ‘0’ that is a fixed value. [0125] 4) A method of, if the location of a spatial merging candidate block referred to derive the reference picture index candidate of the temporal merging candidate of a target prediction block (i.e., e current block) is within a coding block or a location on which coding has not yet been performed, not using the reference picture index of the spatial merging candidate block at the corresponding location in order to derive the reference picture index of the temporal merging candidate. [0126] 5) A method of previously determining a spatial merging candidate block at a specific location that is referred to derive the reference picture index of the temporal merging candidate of a target prediction block (i.e., a current block) and deriving the reference picture index of the temporal merging candidate from the spatial merging candidate block at the specific location. [0127] 6) A method of, if the locations of some of the spatial merging candidate blocks of spatial merging candidates derived to perform mergence on a target prediction block (i.e., a current block) are within a coding block or locations on which coding has not yet been performed and thus pieces of information on the reference picture indices of temporal merging candidates cannot be derived from the spatial merging candidate blocks at the corresponding locations, fixing the spatial merging candidate blocks at the corresponding locations as locations outside the coding block on which coding or decoding has been performed. [0128] The following embodiments of the present invention disclose the methods of deriving the reference picture index of a temporal merging candidate in detail. [0129] First, problems occurring when determining the reference picture index of a temporal merging candidate in the prior art, described with reference to FIG. 5 , are described in detail with reference to FIG. 6 . [0130] FIG. 6 is a conceptual diagram illustrating a method of setting the reference picture index of a temporal merging candidate in accordance with an embodiment of the present invention. [0131] Referring to FIG. 6 , one coding block (e.g., a 2N×2N form) can be partitioned into two prediction blocks (e.g., N×2N). In the first prediction block 600 of the two partitioned blocks, all spatial merging candidate blocks 605 , 610 , 615 , 620 , and 625 are present outside the coding block. In contrast, in the second prediction block 650 of the two partitioned blocks, some (e.g., 655 , 665 , 670 , and 675 ) of spatial merging candidate blocks 655 , 660 , 665 , 670 , and 675 are present outside the coding block, and some (e.g., 660 ) of the spatial merging candidate blocks 655 , 660 , 665 , 670 , and 675 are present within the coding block. [0132] The reference picture index of a temporal merging candidate for a current block (i.e., a target prediction block) can be derived from the reference picture index of a spatial merging candidate. That is, the reference picture index of a temporal merging candidate for a current block can be derived based on information on a reference picture index that has been used by a spatial merging candidate block to perform inter-frame prediction. [0133] For example, it can be assumed that the reference picture indices of three of a plurality of spatial merging candidates for a current block are refIdxLXA, refIdxLXB, and refIdxLXC. Pieces of information on the reference picture indices refIdxLXA, refIdxLXB, and refIdxLXC can become the reference picture index candidates of temporal merging candidates, and the reference picture index values of the temporal merging candidates can be derived based on the reference picture index candidates of the temporal merging candidates. [0134] If the above method is used, spatial merging candidate blocks for a current block need to be coded or decoded in advance because pieces of information on the reference picture indices of the spatial merging candidate blocks for the current block are necessary to derive the reference picture indices of temporal merging candidates for the current block. [0135] Referring back to FIG. 6 , the first prediction block 600 is a block in which the spatial merging candidates are included in locations outside the coding block on which coding or decoding has already been performed as described above. Accordingly, if the first prediction block 600 is a current block on which prediction is performed, the reference picture index candidates of temporal merging candidates for the first prediction block 600 can be directly derived from the spatial merging candidate blocks of the first prediction block 600 . [0136] In the second prediction block 650 , however, some (e.g., 660 ) of the spatial merging candidates are present in the first prediction block 600 that is within the coding block as described above. Accordingly, when inter-frame prediction using merge mode is performed on the second prediction block 650 , the reference picture indices of temporal merging candidates for the first prediction block 650 cannot be derived until the A1 block 660 is coded or decoded, that is, until prediction is performed on the first prediction block 600 including the A1 block 660 . In this case, there is a problem in that inter-frame prediction using merge mode cannot be performed on the first prediction block 600 and the second prediction block 650 in parallel because the temporal merging candidates of the second prediction block 650 are not derived until prediction is performed on the first prediction block 600 . In order to solve the problem, a variety of methods can be used. [0137] Only some of the partition forms of a prediction block are disclosed in the following embodiments of the present invention, for convenience of description, but the present invention can be applied to the partition forms of several prediction blocks of a coding block and embodiments thereof are also included in the scope of the present invention. [0138] FIG. 7 is a conceptual diagram illustrating a method of deriving the reference picture indices of temporal merging candidates in accordance with an embodiment of the present invention. [0139] The embodiment of FIG. 7 discloses a method of setting the locations of spatial merging candidate blocks to which reference is made by a prediction block in order to derive the reference picture indices of temporal merging candidates as locations outside a coding block including a current prediction block. [0140] FIG. 7(A) shows a case where one coding block is partitioned into two prediction blocks 700 and 750 having an N×2N form. [0141] All the spatial merging candidate blocks of the first prediction block 700 are at locations outside a coding unit on which coding or decoding has already been performed. Thus, the reference picture index candidates of temporal merging candidates for the first prediction block 700 can be directly derived by using the already coded or decoded spatial merging candidate blocks. [0142] In the case of the second prediction block 750 , however, the locations of some (e.g., 710 and 720 ) of spatial merging candidate blocks used to derive the reference picture indices of temporal merging candidates can be changed, and the reference picture indices of the temporal merging candidates can be derived from the changed locations. [0143] In order to derive the reference picture index candidates of the temporal merging candidates, the spatial merging candidate block 710 can be replaced with a block 715 outside the coding block without using the spatial merging candidate block 710 included in the coding unit, from among the spatial merging candidate blocks of the second prediction block 750 , and the reference picture index of the block 715 can be used as the reference picture index candidate of a temporal merging candidate. [0144] Furthermore, the spatial merging candidate block 720 can be replaced with a block 725 outside the coding block without using the block 720 outside the coding unit on which coding or decoding has not yet been performed, from among the spatial merging candidate blocks, and the reference picture index of the block 725 can be used as the reference picture index candidate of a temporal merging candidate. [0145] That is, the reference picture index candidates of the temporal merging candidates can be derived by using an A0′ block 725 and an A1′ block 715 outside the coding block instead of the A0 block 710 and the A1 block 720 of the second prediction block 750 . [0146] If the above method is used, all the spatial merging candidate blocks used to derive the reference picture indices of the temporal merging candidates can become blocks included in an already coded block in the second prediction block 750 . Accordingly, in the second prediction block 750 , the reference picture indices of the temporal merging candidates can be derived irrespective of whether or not a prediction process has been performed on the first prediction block 700 . [0147] FIG. 7(B) shows a case where one coding block is partitioned into two prediction blocks having a 2N×N form. [0148] As in FIG. 7(A) , in FIG. 7(B) , instead of a B1 block 780 , that is, a block included within the coding block, and a B0 block 790 , that is, a block on which coding or decoding has not yet been performed, from among the spatial merging candidate blocks of a second prediction block 770 , a B1′ block 785 and a B0′ block 795 that are already coded blocks can be used to derive the reference picture indices of temporal merging candidates for the second prediction block 770 . [0149] FIG. 8 is a conceptual diagram illustrating a method of deriving the reference picture indices of temporal merging candidates in accordance with an embodiment of the present invention. [0150] The embodiment of FIG. 8 discloses a method of setting the reference picture index candidates of temporal merging candidates, derived from a spatial merging candidate block present within a coding block and a spatial merging candidate block present in a location on which coding or decoding has not yet been performed, to ‘0’, if the locations of spatial merging candidate blocks referred to derive the reference picture indices of temporal merging candidates for a target prediction block (i.e., a current block) are within the coding block including the current block or are locations on which coding or decoding has not yet been performed. [0151] FIG. 8(A) shows a case where one coding block is partitioned into two prediction blocks having an N×2N form. [0152] Referring to FIG. 8(A) , all the spatial merging candidate blocks of a first prediction block 800 are at locations outside the coding unit on which coding or decoding has already been performed. Accordingly, the reference picture index candidates of temporal merging candidates for the first prediction block 800 can be derived from the spatial merging candidate blocks of the first prediction block 800 . [0153] In the case of a second prediction block 850 , assuming that the reference picture indices of some spatial merging candidate blocks (e.g., 810 and 820 ) are ‘0’, the reference picture index candidates of temporal merging candidate for the second prediction block 850 can be derived. In relation to a spatial merging candidate block located within the coding block including a target prediction block (i.e., a current block) or a spatial merging candidate block at a location on which coding or decoding has not yet been performed, the reference picture index candidate of a temporal merging candidate derived from a corresponding spatial merging candidate block can be set to ‘0’ and the reference picture index of a temporal merging candidate for the current block can be derived from the set reference picture index candidate. [0154] For example, a process of setting the reference picture index candidates of temporal merging candidates, derived from the A0 block 810 and the A1 block 820 of the second prediction block 850 , to ‘0’ in advance when deriving the reference picture index candidates of the temporal merging candidates and deriving the reference picture indices of the temporal merging candidates from the set reference picture index candidates can be used. [0155] FIG. 8(B) shows a case where one coding block is partitioned into two prediction blocks having a 2N×N form. [0156] All the spatial merging candidate blocks of a first prediction block 860 are at locations outside the coding unit on which coding or decoding has been completed. Accordingly, the reference picture index candidates of temporal merging candidates for the first prediction block 860 can be directly derived from the spatial merging candidate blocks of the first prediction block 860 . [0157] The reference picture index candidate of a temporal merging candidate derived from a spatial merging candidate block 880 included in a prediction block on which prediction has not yet been performed or some spatial merging candidate blocks (e.g., 890 ) at locations on which a coding or decoding process has not yet been performed can be set to ‘0’, when deriving the reference picture indices of temporal merging candidates for a second prediction block 870 . The reference picture index candidates of the temporal merging candidates can be derived from the set reference picture index candidates. [0158] For example, the above method can be used in a process of setting the reference picture indices of temporal merging candidates derived from a B0 block 880 and a B1 block 890 , that is, the spatial merging candidate blocks of the second prediction block 870 , to ‘0’ and deriving the reference picture indices of the temporal merging candidates for the second prediction block 870 . [0159] FIG. 9 is a conceptual diagram illustrating a method of deriving the reference picture indices of temporal merging candidates in accordance with an embodiment of the present invention. [0160] The embodiment of FIG. 9 discloses a method in which a prediction block sets the reference picture index of a temporal merging candidate to ‘0’, that is, a fixed value, and using the set reference picture index. [0161] FIG. 9(A) shows a case where one coding block is partitioned into two prediction blocks having an N×2N form. [0162] Referring to FIG. 9(A) , in order to derive the reference picture indices of temporal merging candidates for a first prediction block 900 and a second prediction block 950 , the reference picture index values of temporal merging candidates can be set to ‘0’ and used, without using spatial merging candidate blocks 905 to 925 and 930 to 947 . If this method is used, the degree of complexity in the deriving of coding and decoding can be reduced and the speed of coding and decoding can be increased because a step of deriving the reference picture indices of temporal merging candidates is not performed. Furthermore, the reference picture indices of temporal merging candidates for a current block can be derived without a need to wait for until prediction on other prediction blocks included in a current coding block is performed. Accordingly, the reference picture indices of temporal merging candidates for a plurality of prediction blocks included in one coding block can be derived in parallel. [0163] FIG. 9(B) shows a case where one coding block is partitioned into two prediction blocks having a 2N×N form. [0164] Likewise, in FIG. 9(B) , in order to derive the reference picture indices of temporal merging candidates for a first prediction block 960 and a second prediction block 990 , the reference picture index values of the temporal merging candidates can be fixed to ‘0’ and used without using spatial merging candidates. [0165] In FIG. 9 , ‘0’ is marked in the spatial merging candidate blocks, for convenience of description. However, when actually deriving the reference picture indices of temporal merging candidates, a value set to ‘0’ can be used without a procedure for searching for the reference picture indices of the spatial merging candidate blocks. ‘0’ is only an example of a fixed picture index, and another picture index other than 0 may be used and embodiments thereof are also included in the scope of the present invention. [0166] FIG. 10 is a conceptual diagram illustrating a method of deriving the reference picture indices of temporal merging candidates in accordance with an embodiment of the present invention. [0167] The embodiment of FIG. 10 discloses a method of, if the location of a spatial merging candidate block referred to derive the reference picture index of a temporal merging candidate for a current block (i.e., a target prediction block) is within a coding block including the current block or at a location on which coding has not yet been performed, not using the reference picture index of the spatial merging candidate block as a candidate for deriving the reference picture index of the temporal merging candidate. [0168] FIG. 10(A) shows a case where one coding block is partitioned into two prediction blocks having an N×2N form. [0169] Referring to FIG. 10(A) , the A1 block 1030 and the A0 block 1020 of a second prediction block 1010 are a block within the coding block including a current block and a block at a location on which coding or decoding has not yet been performed. Pieces of information on the reference picture indices of the A1 block 1030 and the A0 block 1020 cannot be used when deriving the reference picture indices of temporal merging candidates for a first prediction block 1000 . [0170] Accordingly, when deriving the reference picture indices of the temporal merging candidates from the second prediction block 1010 , the pieces of information on the reference picture indices of the A1 block 1030 and the A0 block 1020 can be set to ‘−1’. If the reference picture index value of a specific spatial merging candidate block is ‘−1’, the spatial merging candidate block can indicate a block that is not used to derive the reference picture index of a temporal merging candidate. [0171] FIG. 10(B) shows a case where one coding block is partitioned into two prediction blocks having a 2N×N form. [0172] Referring to FIG. 10(B) , the B1 block 1060 of a second prediction block 1050 is a spatial merging candidate block within the coding block and is a block whose reference picture index information can be known only when prediction is performed on a first prediction block 1040 . The B0 block 1070 of the second prediction block 1050 is a spatial merging candidate block at a location on which coding has not yet been performed, and information on the reference picture index thereof cannot be known. [0173] In this case, in order to derive the reference picture indices of temporal merging candidates from the first prediction block 1040 and the second prediction block 1050 in parallel, pieces of information on the reference picture indices of the B1 block 1060 and the B0 block 1070 can be set to ‘−1’. That is, the B0 block 1070 and the B1 block 1060 may not be used as blocks for deriving the reference picture index candidates of temporal merging candidates for the second prediction block 1050 . [0174] FIG. 11 is a conceptual diagram illustrating a method of deriving the reference picture index of a temporal merging candidate in accordance with an embodiment of the present invention. [0175] The embodiment of FIG. 11 discloses a method of previously determining a specific spatial merging candidate block referred by a prediction block in order to derive the reference picture index of a temporal merging candidate and deriving the reference picture index of the temporal merging candidate from the specific spatial merging candidate block. [0176] FIG. 11(A) shows a case where one coding block is partitioned into two prediction blocks having an N×2N form. [0177] A first prediction block 1100 and a second prediction block 1120 can share spatial merging candidate blocks A0, A1, B0, B1, and B2. That is, the spatial merging candidate blocks A0, A1, B0, B1, and B2 used to perform inter-frame prediction using merge mode in the first prediction block 1100 and the second prediction block 1120 can be blocks outside the coding block. [0178] A reference picture index for the temporal merging of the first prediction block 1100 can be set to the reference picture index value of the B1 block 1105 . That is, the fixed reference picture index of a spatial merging candidate block at a specific location of a prediction block can be set to a reference picture index value for the temporal merging of a current block depending on a partition form. [0179] If the B1 block 1125 is not available, the reference picture index value can be set to ‘0’ and used. [0180] Like in the second prediction block 1120 , the reference picture index value of the A1 block 1125 can be used as a reference picture index for temporal merging. If the B1 block 1105 is not available, the reference picture index value can be set to ‘0’ and used. [0181] FIG. 11(B) shows a case where one coding block is partitioned into two prediction blocks having a 2N×N form. [0182] A first prediction block 1150 and a second prediction block 1170 can share spatial merging candidate blocks A0, A1, B0, B1, and B2. That is, spatial merging candidate blocks for performing inter-frame prediction using merge mode in the first prediction block 1150 and the second prediction block 1170 can be blocks outside the coding block. [0183] A reference picture index for the temporal merging of the first prediction block 1150 can be set to the reference picture index value of the A1 block 1155 . That is, the reference picture index of a spatial merging candidate block at a specific location of a prediction block can be set to a reference picture index value for the temporal merging of a current block depending on a partition form. [0184] If the B1 block 1175 is not available, the reference picture index value can be set to ‘0’ and used. [0185] Like in the second prediction block 1170 , the reference picture index value of the B1 block 1175 can be used as a reference picture index for temporal merging. If the B1 block 1175 is not available, the reference picture index value can be set to ‘0’ and used. [0186] FIG. 12 is a conceptual diagram illustrating a method of deriving the reference picture index of a temporal merging candidate in accordance with an embodiment of the present invention. [0187] The embodiment of FIG. 12 discloses a method of previously determining a specific spatial merging candidate block referred by a target prediction block in order to derive the reference picture index of a temporal merging candidate and deriving the reference picture index of the temporal merging candidate from the specific spatial merging candidate block. [0188] Referring to FIG. 12 , different spatial merging candidate blocks can be used to derive the reference picture index of a temporal merging candidate depending on a form of a prediction block partitioned from one coding block. [0189] For example, in a prediction block, one of an A1 block and a B1 block, from among spatial merging candidate blocks, can be used as a block for deriving the reference picture index of a temporal merging candidate. From among the two spatial merging candidate blocks, a spatial merging candidate block within a coding block is not used to derive the reference picture index of the temporal merging candidate, but a spatial merging candidate block outside the coding block can be used to derive the reference picture index of the temporal merging candidate. [0190] Although FIG. 12(A) showing a case where a coding block is partitioned into prediction blocks having an N×2N form and FIG. 12(B) showing a case where a coding block is partitioned into prediction blocks having a 2N×N form are illustrated for convenience of description, the same method can be applied to a coding block partitioned in various forms. [0191] FIG. 12(A) shows a case where a coding block is partitioned into prediction blocks having an N×2N form. [0192] If one coding block is partitioned into prediction blocks having an N×2N form, the reference picture index of a B1 block 1220 , that is, a spatial merging candidate located outside the coding block and at a location on which coding or decoding has already been performed, from among two spatial merging candidate blocks (e.g., an A1 block 1200 and the B1 block 1220 ), can be set as the reference picture index of a temporal merging candidate for a second prediction block 1210 . [0193] FIG. 12(B) shows a case where a coding block is partitioned into prediction blocks having a 2N×N size. [0194] If one coding block is partitioned into prediction blocks having a 2N×N form, the reference picture index of an A1 block 1240 , that is, a spatial merging candidate outside the coding block, from among two spatial merging candidate blocks (e.g., the A1 block 1240 and a B1 block 1260 ), can be set as the reference picture index of a temporal merging candidate for a second prediction block 1250 . [0195] FIG. 13 is a conceptual diagram illustrating a method of deriving the reference picture index of a temporal merging candidate in accordance with an embodiment of the present invention. [0196] The embodiment of FIG. 13 discloses a method of, if the locations of some of the spatial merging candidates of a prediction block are within a coding block or placed at locations on which coding has not yet been performed, fixing the locations of the spatial merging candidate blocks of the corresponding prediction block to locations outside the coding block and using the fixed locations. [0197] FIG. 13(A) shows a case where one coding block is partitioned into two prediction blocks having an N×2N form. [0198] A first prediction block 1300 can determine spatial merging candidate blocks 1305 , 1310 , 1315 , 1320 , and 1325 on the basis of the first prediction block 1300 . In contrast, a second prediction block 1330 can fix spatial merging candidate blocks to blocks 1335 , 1340 , 1345 , 1350 , and 1355 placed at locations outside the coding block and use the fixed spatial merging candidate blocks. That is, the spatial merging candidate blocks 1335 , 1340 , 1345 , 1350 , and 1355 can be derived on the basis of the coding block, and the derived spatial merging candidate blocks 1335 , 1340 , 1345 , 1350 , and 1355 can be used in inter-frame prediction using merge mode for the second prediction block 1330 . [0199] FIG. 13(B) shows a case where one coding block is partitioned into two prediction blocks having a 2N×N form. [0200] Likewise, in FIG. 13(B) , a first prediction block can use spatial merging candidate blocks derived on the basis of a prediction block. In contrast, the spatial merging candidate blocks 1365 , 1370 , 1375 , 1380 , and 1385 of a second prediction block 1360 can be derived on the basis of the coding block. [0201] FIG. 14 is a flowchart illustrating a method of including a temporal merging candidate in a merging candidate list in accordance with an embodiment of the present invention. [0202] The embodiment of FIG. 14 discloses a process of deriving the reference picture index of a temporal merging candidate by using an index value calculated by the above-described method of deriving the reference picture index of a temporal merging candidate and of including the temporal merging candidate in a merging candidate list. [0203] Referring to FIG. 14 , the reference picture index of a temporal merging candidate is derived at step S 1400 . [0204] The reference picture index of the temporal merging candidate refers to the reference picture index of a picture referred by a current block (i.e., a target prediction block) in order to perform inter-frame prediction using merge mode as described above. The reference picture index of the temporal merging candidate can be derived by several methods of deriving the reference picture indices of temporal merging candidates in parallel in relation to a prediction block. For example, the reference picture index of the temporal merging candidate can be derived by several methods, such as 1) a method of always placing the spatial location of a spatial merging candidate block to be referred outside a coding block, 2) a method of replacing a reference picture index value, derived from a spatial merging candidate block to be referred, with ‘0’ if the spatial location of the spatial merging candidate block is within a coding block, and 3) a method of fixing the reference picture index of a temporal merging candidate to ‘0’ unconditionally. [0205] A temporal merging candidate is derived at step S 1410 . [0206] As described above, the temporal merging candidate can be motion prediction-related information (e.g., predFlag or mvLXCol) derived from a prediction block (e.g., a first temporal merging candidate block) which includes a pixel at a location (xP+nPbW, yP+nPbH) in the colocated picture of a current block on the basis of the location (xP, yP) of a pixel within a picture including the prediction block. If the prediction block including the pixel at the location (xP+nPbW, yP+nPbH) in the colocated picture is not available or is a block predicted by an intra-frame prediction method, motion prediction-related information (e.g., a temporal merging candidate) can be derived from a prediction block (e.g., a second temporal merging candidate block) including a pixel at a location (xP+(nPbW>>1), yP+(nPbH>>1)). [0207] Finally, a final temporal merging candidate block (i.e., a colocated block) used to derive the motion prediction-related information can be a block at a location that has been partially moved on the basis of the locations of the first temporal merging candidate block and the second temporal merging candidate block. For example, if only pieces of motion prediction-related information on some blocks are stored in memory, a temporal merging candidate block present at a location partially moved on the basis of the locations of the first temporal merging candidate block and the second temporal merging candidate block can be determined as the final colocated block for deriving the temporal merging candidate (i.e., motion prediction-related information). [0208] In deriving the temporal merging candidate, different temporal merging candidates can be derived depending on whether a current block is a block using a single merging candidate list or a block not using a single merging candidate list. If the current block is a block using a single merging candidate list, a plurality of prediction blocks included in a coding block can use temporal merging candidates derived from one temporal merging candidate block. If the current block is a block not using a single merging candidate list, a merging candidate list for a plurality of prediction blocks included in a coding block can be generated and inter-frame prediction using merge mode can be performed individually. That is, in this case, the inter-frame prediction can be performed by using temporal merging candidates derived from the temporal merging candidate block for each prediction block. An example in which inter-frame prediction is performed by using a single merging candidate list is described below. [0209] FIG. 15 is a conceptual diagram illustrating a method of generating a single merging candidate list by sharing all spatial merging candidates and temporal merging candidates in a plurality of prediction blocks in accordance with an embodiment of the present invention. [0210] The embodiment of FIG. 15 discloses a method of a plurality of prediction blocks, partitioned from one coding block, generating a single merging candidate list by sharing all spatial merging candidates and temporal merging candidates determined based on the coding block. [0211] Referring to FIG. 15 , a first prediction block 1500 and a second prediction block 1550 can derive spatial merging candidates from the same spatial merging candidate block and share the derived spatial merging candidates. Spatial merging candidate blocks for the first prediction block 1500 and the second prediction block 1550 are blocks determined based on a coding block, and an A0 block 1505 , an A1 block 1510 , a B0 block 1515 , a B1 block 1520 , and a B2 block 1525 can be used as the spatial merging candidate blocks. [0212] The location of each of the spatial merging candidate blocks can be a location including a pixel shown in the drawing on the basis of the upper left location (xC, yC) and nCS (i.e., the size of the coding block) of the coding block. [0213] The A0 block 1505 can be a block including a pixel at a location (xC−1, yC+nCS), the A1 block 1510 can be a block including a pixel at a location (xC−1, yC+nCS−1), the B0 block 1515 can be a block including a pixel at a location (xC+nCS, yC−1), the B1 block 1520 can be a block including a pixel at a location (xC+nCS−1, yC−1), and the B2 block 1525 can be a block including a pixel at a location (xC−1, yC−1). [0214] Furthermore, the first prediction block 1500 and the second prediction block 1550 can share temporal merging candidates. Temporal merging candidate blocks 1560 and 1570 for deriving the temporal merging candidates shared by the first prediction block 1500 and the second prediction block 1550 can be blocks at locations derived on the basis of the upper left locations (xC, yC) of the coding block and the size nCS of the coding block. [0215] The reference picture indices of the temporal merging candidates can be derived by the aforementioned methods. [0216] For example, the temporal merging candidate blocks 1560 and 1570 can include the prediction block 1560 including a pixel at a location (xC+nCS, yC+nCS) in the colocated picture of a current prediction block on the basis of the pixel location (xC, yC) within the picture including the prediction block or can be the prediction block 1570 including a pixel at a location (xC+(nCS>>1), yC+(nCS>>1)) if the prediction block including the pixel at the location (xC+nCS, yC+nCS) is not available. [0217] If temporal merging candidates are not shared, each of the temporal merging candidates for the first prediction block 1500 and the second prediction block 1550 can be derived. [0218] If a method of deriving a single merging candidate list is used, inter-frame prediction can be performed by parallel merging processing performed on each prediction block, and a merging candidate list for each prediction block does not need to be derived separately. Accordingly, by using a single merging candidate list in accordance with an embodiment of the present invention, an image processing speed can be improved in apparatuses, such as Ultra-High Definition TeleVision (UHDTV) that requires a large amount of data processing. [0219] FIG. 15 discloses only the first N×2N prediction block 1500 and the second N×2N prediction block 1550 each partitioned in an N×2N form, but this method can also be applied to prediction blocks partitioned in various forms, such as blocks having different partition forms (e.g., 2N×N, 2N×nU, 2N×nD, nL×2N, nR×2N, and N×N). [0220] Furthermore, in this method, whether or not to apply a single merging candidate list can be differently determined depending on the size of a block or a partition depth. For example, information on whether a single merging candidate list can be used in a specific block or not can be derived on the basis of pieces of information on the size of a block and the size of a coding block on which a merging process can be performed in parallel. For example, information on whether a single merging candidate list can be used in a specific block or not can be represented by flag information. A flag indicating whether or not a single merging candidate list can be used in a specific block can be defined as singleMCLflag (i.e., a single merge candidate list flag). For example, if the single merge candidate list flag singleMCLflag is 0, it can indicate that a block does not use a single merging candidate list. If the single merge candidate list flag singleMCLflag is 1, it can indicate that a block uses a single merging candidate list. Spatial merging candidates for a prediction block can be derived on the basis of a coding block based on a value of the single merge candidate list flag singleMCLflag. [0221] For example, the size of a block on which a merging process can be performed in parallel can derive flag information indicating that a prediction block, partitioned from an 8×8 coding block on the basis of information indicative of a value greater than a 4×4 size and information indicating that the size of a current block is 8×8, uses a single merging candidate list. The derived flag can be used to derive the spatial merging candidates and temporal merging candidates of a prediction block on the basis of a coding block. [0222] Referring back to FIG. 14 , availability information on the temporal merging candidate and a temporal motion vector can be derived on the basis of information on the reference picture index of the temporal merging candidate derived to derive the temporal merging candidate at the step S 1410 . [0223] The availability information on the temporal merging candidate can be used as information indicating whether the temporal merging candidate can be derived on the basis of a temporal merging candidate block. The temporal motion vector can be derived if the temporal merging candidate is available. [0224] Referring back to FIG. 4 , the temporal motion vector mvLXCol can be scaled and derived on the basis of the distance between two pictures derived based on the index of the picture 430 including a temporal merging candidate and the index of the reference picture 440 referred by the colocated picture 410 and the distance between pictures derived based on the index of the colocated picture 410 including the current block 400 and the index of the reference picture of a temporal merging candidate (i.e., the index of the reference picture 460 referred by the current block 400 in inter-frame prediction). [0225] If the temporal merging candidate is available, the temporal merging candidate is included in a merging candidate list at step S 1420 . [0226] When configuring the merging candidate list, if the temporal merging candidate is available based on availability information on the temporal merging candidate derived at the step S 1410 , a corresponding block can be included in the merging candidate list. [0227] FIG. 16 discloses a method in which prediction blocks within the same coding block share spatial merging candidates and temporal merging candidates only when the size of a block is equal to or smaller than a specific size. [0228] FIG. 16 is a conceptual diagram illustrating a method of generating a single candidate list in accordance with an embodiment of the present invention. [0229] The embodiment of FIG. 16 discloses a method in which prediction blocks within the same coding block share spatial merging candidates and temporal merging candidates when the size of the coding block is equal to or smaller than a specific size in inter-frame prediction using merge mode. [0230] Several pieces of information can be used to use a method of sharing a single merging candidate list only in blocks that satisfy a specific condition. For example, information on whether a current block uses a single merging candidate list or not can be derived based on information on the size of a block on which parallel merging processing can be performed and information on the size of a current coding block. Spatial merging candidates and temporal merging candidates for a prediction block can be derived on the basis of a coding block that satisfies the specific condition based on the pieces of derived information. [0231] Referring to FIG. 16(A) , only when conditions that the size of a block on which parallel merging processing can be performed is 8×8 or greater and the size of a coding block is 8×8 are satisfied, for example, prediction blocks partitioned from the coding block can share a single merging candidate list. [0232] It is assumed that a first coding block CU0 1600 has a size of 32×32, a second coding block CU1 1610 has a size of 16×16, a third coding block CU2 1620 has a size of 32×32, a fourth coding block CU3 1630 has a size of 16×16, and a fifth coding block CU4 1640 has a size of 8×8. [0233] FIG. 16(B) is a conceptual diagram only showing spatial merging candidate blocks for some coding blocks. [0234] Referring to FIG. 16(B) , the second coding block 1610 can be partitioned into two prediction blocks 1615 and 1618 having an nL×2N form, and the fifth coding block 1640 can be partitioned into two prediction blocks 1645 and 1650 having an N×2N form. In FIG. 16(B) , it is assumed that a single merging candidate list for only the coding block 1640 having the 8×8 size is generated. [0235] Each of the first prediction block 1615 and the second prediction block 1618 of the second coding block 1610 can derive spatial merging candidates for each prediction block and generate a merging candidate list for each prediction block based on the derived spatial merging candidates. [0236] The size of the fifth coding block 1640 is 8×8, and the fifth coding block 1640 can satisfy conditions of the size of a block on which parallel merging processing can be performed and conditions of the size of a current coding block. In this case, the third prediction block 1645 included in the fifth coding block 1640 and the fourth prediction block 1650 can generate a single merging candidate list based on the spatial merging candidates and the temporal merging candidates derived on the basis of the location and size of a coding block. Accordingly, the reference picture index of a temporal merging candidate can be derived as one value. [0237] The reference picture index of the temporal merging candidate can be derived by the aforementioned methods. [0238] The above-described image coding and image decoding methods can be implemented in the elements of the image coder and the image decoder described with reference to FIGS. 1 and 2 . [0239] Although the present invention has been described, a person having ordinary skill in the art will appreciate that the present invention may be modified and changed in various manners without departing from the spirit and scope of the present invention which are written in the claims below.

The present invention relates to a method and apparatus for setting a reference picture index of a temporal merging candidate. An inter-picture prediction method using a temporal merging candidate can include the steps of: determining a reference picture index for a current block; and inducing a temporal merging candidate block of the current block and calculating a temporal merging candidate from the temporal merging candidate block, wherein the reference picture index of the temporal merging candidate can be calculated regardless of whether a block other than the current block is decoded. Accordingly, a video processing speed can be increased and video processing complexity can be reduced.

CROSS-REFERENCE TO RELATED APPLICATIONS [0001] This application is a continuation in part of commonly assigned U.S. Provisional Patent Application Serial No. 60/108,753 filed Nov. 17, 1998, which is incorporated herein by reference. STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT [0002] Not Applicable BACKGROUND OF THE INVENTION [0003] The present invention is directed generally to optical communication systems. More particularly, the invention relates to the control and operation of optical systems and optical components, such as amplifiers, transmitters, receivers, switches, add/drop multiplexers, filters, etc., and the optical links and networks comprising the systems. [0004] Fiber optic transmission systems generally involve numerous optical links that are arranged in point to point, ring, mesh, or other configurations which are interconnected to provide communication services over a geographic region. Each of the various links must be managed and operated to ensure the proper flow of communications traffic within the link. The interconnection of the various links requires additional management oversight and control to ensure the smooth flow communications traffic between the various transmission links in the system. [0005] As used herein, communications traffic should be interpreted in its broadest sense to include audio, video., data, and other forms of information that can be optically transferred. Likewise, the term “system” should be broadly construed to include a single linear link consisting of an optical transmitter and an optical receiver, as well as optical networks including pluralities of diversely located transmitters and receivers that are interconnected by one or more optical fibers and various optical components, such as optical switches, amplifiers, add/drop devices, filters, equalizers, etc. [0006] The necessity of simultaneously managing the individual transmission links and a network of links has led to the development of standardized hierarchical approaches to optical network management. One such standardized structure, known as the Telecommunication Management Network (“TMN”) structure, allocates the management responsibilities over number of management levels, as generally shown in FIG. 1. [0007] In the TMN structure, a Network Management Layer (“NML”) performs monitoring and control functions on a network basis. High level network tasks, such as establishing network connectivity including establishing primary and protection paths and wavelength management functions are performed through the NML. A Service Management Layer (“SML”) is provided for communications service providers to interface with one or more NML reporting to the service layer. The SML is used to provision the network as required to meet communication traffic patterns in the system and report to service configuration to a Business Management Layer (“BML”) of the service provider. [0008] The TMN structure separates the network management functions into two layers to provide a hierarchical division of the management functions. The NML receives high-level network configuration instructions from the SML and develops a general set of element instructions necessary to implement the network instructions. The NML sends the general element instructions to an Element Management Layer (“EML”), in which a plurality of element managers are typically used to oversee a Network Element Layer (“NEL”). The NEL includes the optical components and associated hardware that comprise the actual transmission system and which are generally referred to as network elements (“NE”). Each network element, or optical component, generally includes a network element, or optical component, controller that controls the operation of the component in accordance with the specific element instructions from the element manager. [0009] Communication between the various TMN layers is generally follows established protocols, such as SNMP (Signaling Network Management Protocol), CMIP (Common Management Information Protocol), CORBA (Common Object Request Broker Architecture), Java, Q3, etc. The network and element managers and the component controllers generally are configured according-to protocols, such as GDMO (Guideline for Definition of Managed Objects) and its derivatives, as well as other standard protocols. Whereas, the component controller typically control the sub-components using proprietary protocols particular to the optical system. [0010] In the operation of the optical system, element managers are generally assigned to one or more network elements that will usually, but not necessarily, be interconnected in one or more specific links, or segments, in the network. The network manager sends the general element instructions to the element managers. Each element manager generates specific element instructions for its managed network elements from the general element instructions. The specific network element instructions can be distributed directly to optical components either, for example via a local, metropolitan, or wide area network (LAN, MAN, or WAN, respectively). Alternatively, specific network element instructions can be distributed remotely via a supervisory or service channel that provides communication between the network elements in the NEL. [0011] The component controller not only receives and process the specific element instructions, but controls all work functions performed in the component including those performed by component peripherals, or sub-components, such as pumps, heaters, coolers, current sources, etc. The component controller also monitors the sub-component performance and provides status information to the element manager for higher level and/or redundant analysis and monitoring. [0012] In many systems, the operation of the sub-components in the optical component are controlled by the component controllers and performed with reference to one or more Management Information Bases (MIBs). The MIBs provide operational parameters for each controllable portion of the component as a function of monitored operating characteristics of the optical components. The component controller monitors the operating characteristics and controls the operation of the component and its sub-components in accordance with its associated MIBs. [0013] The element managers monitor the performance of the network elements/optical components for compliance with the general element instructions and generate element status reports on the network element status. The network manager monitors the element status reports from the element managers to ensure compliance with the network instructions and provides a network report with respect to the network instructions to the service manager. [0014] A shortcoming with conventional TMN based systems is that control of the actual operation of the optical system has been pushed down through the management hierarchy to the network element level. Thus, the TMN structure involves a plurality of management layers that provide oversight responsibilities, but the component controllers are solely responsible for control of multiple tasks that must be coordinated and monitored to ensure correct operation of the component. As such, the component controller represents a single point of failure that could disable the component, as well as a link and possibly larger segments of the network. [0015] The traditional view toward addressing the risk of a component controller failure has been to provide controllers having increased processing power and reliability or redundant controllers. However, the use of higher performance component controllers does not ameliorate the consequences of a component controller failure, but merely reduces the risk of component failure. High performance controllers also tend to increase the local heat generation of the component, which increases the cooling requirements of the system. Whereas, redundant controllers provide additional protection against a controller failure, but further increases the complexity of the control structure, thereby increasing the probability of a controller malfunction. In view of the substantial problems that can result from component controller failures and malfunctions, it would be desirable to have a network management structure that reduces the risks associated with component controller failures to provide robust optical systems. BRIEF SUMMARY OF THE INVENTION [0016] The present invention addresses the need for higher reliability optical transmission systems, apparatuses, and methods. Optical systems of the present invention include a network control architecture that provides for distributed control of the optical component work functions and network management. The distribution of the work function control in the network element provides for a hierarchical division of work function responsibilities. The hierarchical division provides for streamlined and specically tailored control structures that greatly increases the reliability of the network management system. [0017] In various embodiments, dedicated work function controllers are provided for each work function performed in the optical component. For example, work function controllers can be used to control the performance of one or more laser diodes used in the system. In addition, the work function can be further distributed, when particular work function are performed multiple times in the network element. Continuing the example, a work function controller can be provided for each laser diode to allow for individual control over that diode. An overall laser diode work function controller can be used to oversee the individual laser diode controllers and report the overall laser diode status to the component controller. [0018] In addition, communication bypass can be provided to allow the element managers to communicate directly with work function controllers in the event of a component controller failure. The bypass can be established by providing a redundant component controller that serves during normal operation solely as a work function controller, but in fault condition can dually operate as a component controller and work function controller. Alternatively, a bypass can be provided to allow direct communication between the element managers and the work function controller. Similarly, in multiple layered work function architectures, communication bypass can be provided the optical component controllers and the lower level work function controllers. [0019] Thus, necessary for higher performance optical systems. These advantages and others will become apparent from the following detailed description. BRIEF DESCRIPTION OF THE DRAWINGS [0020] Embodiments of the present invention will now be described, by way of example only, with reference to the accompanying drawings for the purpose of illustrating embodiments only and not for purposes of limiting the same; wherein like members bear like reference numerals and: [0021] [0021]FIG. 1 show the standard Telecommunications Management Network hierarchical structure; [0022] [0022]FIG. 2 show the Telecommunications Management Network hierarchical structure of the present invention; [0023] [0023]FIG. 3 show a network management system structure; [0024] FIGS. 3 - 5 show optical system embodiments. DESCRIPTION OF THE INVENTION [0025] An optical system 10 of the present invention is provisioned such that the actual operation and control network element/optical components 12 in the system 10 is distributed among autonomous work function controllers 14 i in the component 12 . The autonomous work function controllers 14 i provide dedicated control over one or more assigned work functions being performed in the optical component 12 . Whereas, component controllers 16 are used to monitor, control the work function controllers 14 i in the component 12 , and possibly provide direct work function control if a work function controller malfunctions. [0026] The hierarchical division of optical component control functions between the component controllers 16 and the work function controllers 14 i provides for distributed architecture for implementing and control work functions in the system 10 . The distributed work function architecture can be considered a new layer in the TMN structure as shown in FIG. 2, as the Work Function Layer. [0027] The distribution of component operation responsibilities tends to lessen the impact on the system, if one or more work function controllers 14 or the component controller 16 were to fail. In addition, the distribution of processing function between multiple layers in the optical component increase the system performance by focusing both the component controller and the work function controller resources on a small number of tasks. The distribution of the processing in the component also increases the thermal performance of the system by distributing the heat load that must be dissipated during operation. [0028] The work function controller 14 also provides the capability to reconfigure work function performance characteristics and provide multiple control level oversight of the work functions. The reconfigurable work function allows the operation of the optical component 12 to be changed as the network requirements are updated or the system 10 is reconfigured. The distribution of the processing responsibilities also facilitate less complicated updates because of the limited responsibilities of each controller. This, in turn, also tends to lessen the consequences of programming errors in the controllers 14 and 16 . [0029] In the present invention, the component controller 16 is configured to receive element instructions from an element manager EM and provide work function instructions to one or more work function controllers 14 i . The work function controllers 14 i control and monitor the work functions pursuant to work function instructions either provided by the component controller 16 . In the absence of specific instructions from the component controller 16 , the work function controllers 14 i can operate using default instructions in accordance with its associated MIBs, which can reside in local memory on work function controller 14 i. [0030] The work function controller 14 i will generally control the operation of one or more component peripherals, or subcomponents, such as optical and electrical sources, filters, switches, etc. The work function controller 14 i can serve as temperature controllers, voltage and current controllers, and mechanical controllers for use with the sub-components. [0031] In an optical link, only certain optical components 12 are directly connected to the element manager EM, which are referred to herein as optical component nodes 12 N. The other optical components communicate with the element manager EM via the optical nodes 12 and are referred to remote optical compenents 12 R. [0032] The use of optical nodes 12 N decreases the number of optical components 12 that must interface with an element manager and can provide additional oversight control over remotely connected optical components 12 R. The component controllers 16 in the optical nodes 12 N can be configured to pass system information between the element manager and the remote components 12 R within the system 10 . The component controllers 16 in the optical nodes 12 N can also be configured to implement network protection schemes in the system 10 . [0033] [0033]FIG. 3 shows an embodiment of the optical system 10 , in which the element manager EM interfaces, either directly or remotely, with the one or more network elements/optical components 12 . The optical components 12 may include one or more transmitters 20 , optical amplifiers 22 , optical switches 24 , optical add/drop multiplexers 26 , and receivers 28 in optical systems 10 . The optical components 12 can be deployed in various configurations, such as described in commonly assigned, U.S. patent application filed herewith as Docket No. 981117DS entitled “Wavelength Division Multiplexed Optical Transmission Systems, Apparatuses, and Methods”, the disclosure of which is incorporated herein by reference. [0034] As described in the incorporated reference, element instructions and other system information can be transmitted through the optical system 10 using either a dedicated service channel or a mixed data channel carrying both communications traffic and system information. For example, communication between the element managers EM and the remote optical components 12 R can be provided through an optical mixed data channel Λomd via the optical component nodes 12 N. The mixed data channel Λmd also provides for component to component communication with the network element layer and other service provider communications, such as order wires, etc. [0035] As shown in FIG. 4, remote optical components 12 R generally include an optical/electrical converter O/E to receive an optical mixed data channel Λomd,IN via an optical fiber 30 . The optical mixed data channel Λomd,IN is converted to an electrical mixed data channel Λemd,IN and system supervisory information pertinent to the remote component 12 R, i.e., element instructions, is provided to the component controller 16 . The controller 16 upon receipt of the element instructions provides corresponding work function instructions to the work function controller 14 i . The work function controllers will generally perform a work function affecting the communications traffic passing through the optical fiber 30 . [0036] The work function controllers 14 i in the optical component 12 monitor the work function and provide status reports. The component controller 16 monitors the status of the work function controllers 14 i for compliance with the work function instructions. The component controller 16 also generates a component status report that is multiplexed with the communication traffic and other information carried by the mixed data channel to provide an electrical mixed data channel output signal Λemd,OUT. An electrical to optical converter E/O, e.g. transmitter, converts the electrical mixed data channel output signal Λemd,OUT to an optical signal Λomd,OUT that is transmitted via the optical fiber 30 to the next optical components 12 . [0037] Likewise, in FIG. 4, optical nodes 12 N can send and receive system information via the mixed data channel, and additionally, will directly interface with the element manager EM. The optical nodes 12 N report their own component status, as well as the component status of the remote optical components 12 R and other optical nodes 12 N received via the mixed data channel. [0038] Upon receiving element instructions from the element manager EM, the component controller 16 at the optical nodes 12 N will forward the element instructions to remote optical components 12 R through the mixed data channel. The optical node component controller 16 will also generate and send work function instructions to the work function controllers associated with the optical node 12 N. The element manager EM can also be configured to send element instructions to a first optical node 12 N 1 through at least a second optical node 12 N 2 . The element instruction will then be forwarded through the mixed data channel to the first optical node 12 N 1 to provide one or more redundant links between the element manager EM and the optical nodes. [0039] While the above implementation was described with respect to a mixed data channel, a dedicated service channel can also be provided. In addition, the element instructions and other system information can be counter-propagated and/or co-propagated along with the communications traffic and transmitted over one or more fibers depending upon the transmission system. [0040] If two fibers are available in a transmission path, such as shown in FIG. 3, then system information can be propagated in both directions and redundant system information will reach the element manager EM during normal operation. The element manager EM can be configured to correlate the redundant information to identify discrepancies as will be discuss further herein. [0041] In the present invention, the component controllers 16 can be any microprocessor suitable for performing the monitoring and control functions for the component. For example, a Motorola 860 microprocessor or other microprocessor of comparable or greater capabilities can be used as component controllers 16 . The duties of work function controllers 14 i can generally be performed using a microcontroller, such as the Atmel AVR Mega 103 or other microcontrollers or microprocessors of comparable or greater capabilities. [0042] Many optical components have a number of work functions being performed, such as in an optical switch or add/drop multiplexer, or are often collocated at a site, such as a rack of transmitters and/or receivers. In these components or configurations, it may desirable to use more than one component controller 16 . To facilitate communication with the element manager EM, one component controller 16 can be designated to act as a primary/master central processor that is used to interface with element managers. The remaining central processors serve as secondary/slave processors that interface with the primary central processor analogous to the communication between the component controller and the work function controllers. [0043] Communication between the primary central processor and the secondary component controllers 16 and the work function controllers 14 i can be provided using standard communications protocols, such as Ethernet, ATM, RS-485 multidrop, or HDLC multimaster, or proprietary protocols as may be appropriate. In addition, one or more secondary controllers can be configured to serve as the primary controller in the event of a primary central processor failure. Redundant component controllers and work function controllers also can be used to further militate against catastrophic controller failures. [0044] Illustratively, the work function controllers 14 i for use in optical components may control and oversee work functions including the operation and control of: pump and signal laser power, wavelength stabilization, optical signal detection, pump laser temperature stabilization, Bragg grating and other filter stabilization, on/off gate switching, E/O and O/E signal conversion, and detector wavelength stabilization. The precise work functions performed by each optical component will vary depending upon the responsibilities of each component. For example, laser signal power control, wavelength and temperature stabilization may be performed in transmitters for signal lasers and amplifiers for pump lasers. Likewise, Bragg grating stabilization can be performed in receivers, switches, add/drop devices, as well as in amplifiers or transmitters. [0045] The present invention can be further described by way of example. If a fiber is cut in a transmission link, for example, at point B in FIG. 3, an optical signal sent by the transmitter 20 will not reach the optical amplifier 22 . A signal detection work function controller can be provided to sense the presence/absence of signal being sent by the transmitter 20 . If no optical signal is detected, the signal detection work function controller 14 can initiate an amplifier shutdown procedure, such as laser pump shutdown, and report the loss of signal to the amplifier component controller 16 . [0046] The component controller 16 , in turn, can correlate the work function status provided by the signal detection work function controller with status reports from other work function controllers. Upon correlation of the status reports, the component controller 16 can instruct the signal detection controller whether or not to continue shutdown procedures. In this instance, the component controller provides local processing and control that could prevent an unnecessary shut down of the amplifier pump laser in the case of signal detector failure. [0047] Continuing, the amplifier component controller 16 can then report the component status via the mixed data channel in both directions to the optical component nodes 12 N, including the transmitter 20 and the optical switch 24 , respectively. Component status reports will indicate a possible fiber cut between the transmitter 20 and the amplifier 22 . If the element manager receives the amplifier component status report only from the optical switch 24 , the element manager EM will have corroborating evidence that a fiber cut exists as provided in the amplifier component status report. The element manager EM will then send a network status report to the network manager NM indicating the fiber cut and the network manager will take appropriate action to reroute communications traffic passing through the link. [0048] In this example, providing service channel information from both directions allows for the remote shut down of lasers, as well as other actions that may be necessary in the event of a fiber cut. As previously discussed, the transmitter and optical switch status reports from the transmitter optical node can also be sent via service channel to the other optical nodes. The absence of a duplicate status report from the transmitter and the optical switch would provide a further indication of a fiber cut. [0049] It is often desirable to configure work function controllers 14 i to operate in accordance with default values and/or the last work instructions provided by component controller 16 . In those configurations, the work function controllers 14 i will continue to operate in a controlled manner according to the last received work instructions or default instructions in the event of component controller 16 failure. The ability to continue operation upon the failure of a component controller 16 or work function controller 14 i is particularly useful in optical amplifier components, which are often remotely located. [0050] For example, if an optical amplifier controller 16 fails, the work function controllers 14 i will continue to operate pump diodes and other sub-components. While the system performance may not degrade, the lack of component status report from the amplifier controller 16 to the element manager EM will indicate that the amplifier controller 16 has failed. Corroborating evidence of the amplifier controller failure will be provided if other components along the link do not indicate a problem. [0051] Conversely, if a work function controller fails, the lack of status report will indicate a possible work function controller failure to the amplifier controller. If the amplifier controller determines that a failure has occurred, the amplifier controller can modify the work function instructions of any other work function controllers under its control to mitigate the effect of the failure. For example, a redundant pump could be activated in the case of a pump failure, or other work functions can be adjusted in accordance with the work function MIB to compensate for the failure. The amplifier controller will provide a component status report to the element manager EM indicating the work function controller failure. It may also be possible for the component controller to bypass the failed work function controller and provide work function control of the work function. [0052] Those of ordinary skill in the art will appreciate that numerous modifications and variations that can be made to specific aspects of the present invention without departing from the scope of the present invention.

Systems, apparatuses, and methods are disclosed that include network control architectures that provide for distributed control of the optical component work functions and network management. The distribution of the work function control in the network element provides for a hierarchical division of work function responsibilities. The hierarchical division provides for streamlined and specically tailored control structures that greatly increases the reliability of the network management system.

CROSS-REFERENCE TO RELATED APPLICATIONS [0001] None STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT [0002] None BACKGROUND OF THE INVENTION [0003] This invention relates to a counter-flow asphalt plant used to produce a variety of asphalt compositions. More specifically, this invention relates to a counter-flow asphalt plant having a recycle asphalt (RAP) feed to the combustion zone to produce high percentage RAP asphalt products within a two stage mixing zone to improve production rates with greater economy and efficiency of plant design and operation. [0004] Several techniques and numerous equipment arrangements for the preparation of asphaltic compositions, also referred by the trade as “hotmix” or “HMA”, are known from the prior art. Particularly relevant to the present invention is the continuous production of asphalt compositions in a drum mixer asphalt plant. Typically, water-laden virgin aggregates are dried and heated within a rotating, open-ended drum mixer through radiant, convective and conductive heat transfer from a stream of hot gases produced by a burner flame. As the heated virgin aggregate flows through the drum mixer, it is combined with liquid asphalt and mineral binder to produce an asphaltic composition as the desired end-product. Optionally, prior to mixing the virgin aggregate and liquid asphalt, reclaimed or recycled asphalt pavement (RAP) may be added once it is has been crushed or ground to a suitable size. The RAP is typically mixed with the heated virgin aggregate in the drum mixer at a point prior to adding the liquid asphalt and mineral fines. [0005] The asphalt industry has traditionally faced many environmental challenges. The drum mixer characteristically generates, as by-products, a gaseous hydrocarbon emission (known as blue smoke), various nitrogen oxides (NO X ) and sticky dust particles covered with asphalt. Early asphalt plants exposed the liquid asphalt or RAP material to excessive temperatures within the drum mixer or put the materials in close proximity with the burner flame which caused serious product degradation. Health and safety hazards resulted from the substantial air pollution control problems due to the blue-smoke produced when hydrocarbon constituents in the asphalt are driven off and released into the atmosphere. The exhaust gases of the asphalt plant are fed to air pollution control equipment, typically a baghouse. Within the baghouse, the blue-smoke condenses on the filter bags and the asphalt-covered dust particles stick to and plug-up the filter bags, thereby presenting a serious fire hazard and reducing filter efficiency and useful life. Significant investments and efforts were previously made by the industry in attempting to control blue-smoke emissions attributed to hydrocarbon volatile gases and particulates from both the liquid asphalt and recycle material. [0006] The earlier environmental problems were further exacerbated by the processing technique standard in the industry which required the asphalt ingredients with the drum mixer to flow in the same direction (i.e., co-current flow) as the hot gases for heating and drying the aggregate. Thus, the asphalt component of recycle material and liquid asphalt itself came in direct contact with the hot gas stream and, in some instances, even the burner flame itself. [0007] Many of the earlier problems experienced by asphalt plants were solved with the development of modern day counter-flow technology as disclosed in my earlier patent Hawkins U.S. Pat. No. 4,787,938 which is incorporated herein by reference and which was first commercially introduced by Standard Havens, Inc. in 1986. The asphalt industry began to standardize on the counter-flow processing technique in which the ingredients of the asphaltic composition and the hot gas stream flow through a single, rotating drum mixer in opposite directions. Combustion equipment extends into the drum mixer to generate the hot gas stream at an intermediate point within the drum mixer. Accordingly, the drum mixer includes three zones. From the end of the drum where the virgin aggregate feeds, the three zones include a drying/heating zone to dry and heat virgin aggregate, a combustion zone to generate a hot gas stream for the drying/heating zone, and a mixing zone to mix hot aggregate, recycle material and liquid asphalt to produce an asphaltic composition for discharge from the lower end of the drum mixer. [0008] Not only did the counter-flow process with its three zones vastly improve heat transfer characteristics, more importantly it provided a process in which the liquid asphalt and recycle material were isolated from the burner flame and the hot gas stream generated by the combustion equipment. Counter-flow operation represented a solution to the vexing problem of blue-smoke and all the health and safety hazards associated with blue-smoke. [0009] A more complete understanding of the early equipment and processing techniques used by the asphalt industry can be found in the extensive listing of prior art patents and printed publications contained in my earlier patents Hawkins U.S. Pat. No. 5,364,182 issued Nov. 15, 1994, Hawkins U.S. Pat. No. 5,470,146 issued Nov. 28, 1995, and Hawkins U.S. Pat. No. 5,664,881 issued Sep. 9, 1997. Indeed, as a result of my first patent Hawkins U.S. Pat. No. 4,787,938 becoming involved in protracted litigation, the prior art collection cited in the foregoing patents is thought to be a thorough and exhaustive bibliographic listing of asphalt technology and such prior art is specifically incorporated herein by reference. [0010] With many of the health and safety issues associated with asphalt production solved by the advent of counter-flow technology, contemporaneous attention has now shifted to operational inefficiencies which are manifest as excessive design and production costs and poor economy of operation from excess energy consumption. [0011] Experience has shown that the environmentally desirable use of a recycled material (RAP) in asphalt production comes with disadvantageous tradeoffs in energy consumption. The most energy efficient plant operation is achieved when no RAP is added. In such circumstances, for example, all virgin aggregate is introduced in one end of the dryer and flows as a falling curtain or veil of material in counter-current heat exchange with hot gases generated at the opposite end of the dryer. The shell temperature is characteristically about 500° F. and the exhaust gas is about 225° F. which is within the normal operating temperature for the baghouse used to filter the exhaust gas of particulate matter. The temperature of the exhaust gas stream is determined by the design of the dryer, but must be kept above its dew point to prevent moisture from condensing in the exhaust ductwork and especially in the baghouse itself. A temperature of 225° F. is sufficient, but since varying conditions during operation can cause relatively large temperature swings, most operations are controlled to keep exhaust temperatures in the range of 250° F. to 275° F. [0012] The addition of RAP material has a significant effect on operating temperatures of the process. Conventional wisdom has taught that the RAP cannot be directly dried without burning the liquid asphalt and causing hydrocarbon smoke emissions. Accordingly, it has previously been dried indirectly by superheating the virgin aggregates and then mixing the superheated aggregates with the RAP to achieve a blended mixture temperature. This results in much higher exhaust gas temperatures and a resulting loss in fuel efficiency. Accordingly, 20 to 40% RAP feeds (that is, operations wherein RAP makes up 20 to 40% of the final asphalt composition) have been close to the upper end of the range heretofore workable in modern counter-flow asphalt plants. Although a 50% RAP feed has been achievable, it has been at the cost of high energy and reduced equipment life. Consequently, an upper limit of approximately 40% RAP has been a realistic upper limit for the majority of asphalt plants. The operating conditions necessary are illustrative of the problems. If 50% RAP is introduced midstream in the process, then only 50% virgin aggregates are used. This means that only half the material is present, as compared to the 100% virgin aggregate production, to be heated and only half the veiling of material in the drying section of the drum occurs which yields poor heat transfer characteristics. Under such circumstances, the combustion zone temperature must be elevated significantly to superheat the virgin aggregate. This, in turn, causes the shell temperature of the drum to range from 750-800° F. and the exhaust gas temperature to increase to about 375° F. The exhaust gas temperature will now exceed the upper limit for a baghouse using polyester bags which have an upper service of about 275° F. Accordingly, more costly filter bags constructed of less heat sensitive material such as NOMEX (an aramid fiber marketed by DuPont) have to be installed in the baghouse whenever higher RAP feed operations are contemplated. Moreover, any time the combustion zone temperature rises to about 2800° F. or greater then the production of various nitrogen oxides (NO X ) as a product of combustion becomes a problem. [0013] The foregoing problems associated with processing high percentage RAP are further exacerbated by the moisture content of the RAP itself. The superheat of the virgin aggregate must be sufficient to not only heat the RAP material to an appropriate mix temperature, but also supply the necessary heat to vaporize the moisture content of the RAP. [0014] Accordingly, modern asphalt plants characteristically introduce RAP in one of two ways. Using the first method, RAP is introduced directly into an isolated mixing zone where all heat transferred to the RAP must necessarily come from superheated virgin aggregate. Using the second method, the RAP is introduced into the combustion zone but shielded from direct radiant heat by an inner shell or by special flighting to preheat the RAP by convective and conductive heat transfer before it is delivered to an isolated mixing zone. [0015] Asphalt plants constructed like Hawkins U.S. Pat. No. 4,787,938 and other counter-flow drum mixers that followed utilized an isolated mixing zone to prevent blue smoke. For the most part they did so successfully, although not completely. However, unwanted consequences resulted from this processing technique, particularly as the use of RAP addition to asphalt compositions increased. By isolating the mixing zone from the gas stream, they create a dead zone in which any blue smoke and moisture vapor that forms within the mixing zone is not adequately evacuated. Though most of the blue smoke is eliminated by shielding the liquid asphalt exposure to the radiant heat of the flame and from exposure to the hot exhaust gas stream, smoke is generated in the mixing zone when the liquid asphalt comes in contact with the hot aggregate. This is especially true when the aggregate is superheated, as in high percentage recycle operations. Since the blue smoke is generated in a dead zone, it tends to flow with the exiting production material, and exit the drum mixer at the material discharge port. In most cases this is overlooked by the environmental agencies because it is the exhaust gas stack, and not the material discharge port, that they are charged with monitoring and enforcing pollution regulations. Still, it is likely only a matter of time until the focus of environmental protection is trained on the discharge area. Some areas of the country are already requiring blue smoke control systems for the discharge and loadout areas of an asphalt plant. [0016] A similar problem exits with the evacuation of moisture vapor from the dead zone of an isolated mixing chamber. This is particularly true when, as in most cases, the cold, wet recycle material is introduced into the mixing zone where the moisture content is vaporized by the superheated aggregate. The resulting steam explosion from the rapidly vaporized recycle moisture causes steam and dust to be forced from the drum mixer, generally at the recycle feed collar and to some extent at the drum discharge port. [0017] A need remains in the industry for an improved counter-flow asphalt plant design capable of utilizing high percentage RAP mixes and for operating techniques to address the problems and drawbacks heretofore experienced with modern counter-flow production. The primary objective of this invention is to meet this need. BRIEF SUMMARY OF THE INVENTION [0018] More specifically, an object of the invention is to provide a counter-flow asphalt plant capable of routinely using high percentage RAP mixes (e.g., up to 50% RAP) without emitting excessive blue smoke or without excessive energy requirements. [0019] Another object of the invention is to provide a counter-flow asphalt plant capable of effectively evacuating blue smoke and steam from the mixing zone in an environmentally friendly manner even when processing high percentage RAP mixes. [0020] Another object of the invention is to provide a counter-flow asphalt plant capable of processing up to 50% RAP mixes with extended equipment life by eliminating the need to superheat virgin aggregates with the associated temperature elevation of the processing equipment. [0021] An alternative object of the invention is to provide a counter-flow asphalt plant capable of processing RAP mixes greater than 50% by utilizing superheating techniques together with the processing techniques which are the subject of this invention. [0022] Another object of the invention is to provide counter-flow drum mixer equipment and method of operation for retrofitting existing asphalt plants to increase production capacity by reducing the total volume and temperature of the combustion gases present in the equipment for a given production rate. [0023] A corollary object of the invention is to provide counter-flow drum mixer equipment and method of operation of the character previously described for retrofitting existing asphalt plants to increase production capacity by as much as 20%. [0024] An additional object of the invention is to provide counter-flow drum mixer equipment of a reduced size for a given production rate for savings in original equipment costs, as well as savings in operating costs, by reducing the total volume and temperature of the combustion gases necessary to achieve a given production rate in a conventional counter-flow plant. [0025] A corollary object of the invention is to provide counter-flow drum mixer equipment and method of operation of the character previously described that reduces by as much as 20% the size of the equipment required to produce a given volume of product. [0026] A further object of the invention is to provide a counter-flow drum mixer to permit RAP material to be introduced directly into the combustion zone to take full advantage of radiant, convective and conductive heat transfer. [0027] Yet another object of the invention is to provide counter-flow drum mixer and method of operation for reducing NO X emissions for processing techniques utilizing both virgin material mixes and RAP with virgin material mixes. [0028] An additional object of the invention is to provide counter-flow drum mixer and method of operation which both reduces in size and operates more economically the air handling equipment and dust collection system required for asphalt production. [0029] Another object of the invention is to provide counter-flow drum mixer and method of operation for which the exhaust gas temperatures are substantially lower than in conventional systems (225 F. average vs. 375 F. average in a typical 50% recycle plant) to permit the use of polyester filters in the dust collection system for a savings of 80% in filter cost over conventional systems. [0030] A further object of the invention is to provide a counter-flow asphalt plant of the character described having improved efficiency of operation and production consistency of finished product conforming to specifications. [0031] An additional object of the invention is to provide a counter-flow asphalt plant of the character described having more precise control over operating parameters to achieve a uniform end-product and more precise control over energy requirements for improved economic operation. [0032] An added object of the invention is to provide a counter-flow asphalt plant of the character described which meets or exceeds modern day environmental standards. [0033] A further object of the invention is to provide a counter-flow asphalt plant of the character described which is both safe and economical in operation. Efficient operation results in improved fuel consumption and in reduced air pollution emissions. [0034] Other and further objects of the invention, together with the features of novelty appurtenant thereto, will appear in the detailed description of the drawings. [0035] In summary, a counter-flow drum mixer asphalt plant equipped with a secondary feeder for introducing RAP to direct radiant heat of the combustion zone. Heated virgin aggregate and RAP in the combustion zone are delivered through a transition piece to a first stage of the mixing zone where liquid asphalt is combined with the materials and secondary combustion air flows through the first stage to evacuate blue smoke and steam back to the combustion zone. The second stage of the mixing zone is substantially isolated from secondary combustion air flow where dust and mineral fines are introduced and mixed to complete the asphalt product discharged from the mixing zone. Alternative constructions of the mixing zone are disclosed to provide the first and second stages having such characteristics, as well as options for both the passive and active control of the secondary combustion air. An optional secondary burner in the exhaust housing elevates the temperature of the exhaust gas above its dew point temperature before delivery to the baghouse. BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING [0036] In the following description of the drawings, in which like reference numerals are employed to indicate like parts in the various views: [0037] FIG. 1 is a side sectional view of a prior art counter-flow asphalt plant in order to compare and contrast the teachings of this invention; [0038] FIG. 2 is a side view of a single drum, counter-flow asphalt plant constructed in accordance with a first preferred embodiment of the invention; [0039] FIG. 3 is a side sectional view of a counter-flow asphalt plant similar to FIG. 2 to better illustrate the details of construction and pertinent operational features of the equipment; [0040] FIG. 4 is an end sectional view of a portion of the exhaust ductwork, the associated exhaust gas heater and a schematic illustration of the temperature control system as taken from the right hand end of FIG. 3 ; [0041] FIG. 5 is an enlarged side view of the combustion zone recycle feed assembly for use with the asphalt equipment disclosed herein; [0042] FIG. 6 is an enlarged side sectional view of the combustion zone recycle feed assembly shown in FIG. 5 to better illustrate the internal details of construction; [0043] FIG. 7 is an enlarged end sectional view taken along line 7 - 7 of FIG. 3 in the direction of the arrows to better illustrate the details of the combustion zone flighting in relation to the internal details of the feed collar; [0044] FIG. 8 is an enlarged fragmentary view taken along line 8 - 8 of FIG. 7 in the direction of the arrows to show the support brackets of the combustion zone flighting; [0045] FIG. 9 is an enlarged end sectional view taken along line 9 - 9 of FIG. 3 in the direction of the arrows to better illustrate the details of the venture cone and support structure at the transition region of the combustion zone to the mixing zone; [0046] FIG. 10 is an enlarged end sectional view taken along line 10 - 10 of FIG. 3 in the direction of the arrows to better illustrate the details of the mixing zone; [0047] FIG. 11 is a side sectional view of a single drum, counter-flow asphalt plant constructed in accordance with a second preferred embodiment of the invention similar to the asphalt plant of FIG. 3 but with provisions for total control of both primary and secondary combustion air; [0048] FIG. 12 is a side sectional view of a single drum, counter-flow asphalt plant constructed in accordance with a third preferred embodiment of the invention with a modified mixing zone and aspirated secondary combustion air; and [0049] FIG. 13 is a side sectional view of a single drum, counter-flow asphalt plant constructed in accordance with a fourth preferred embodiment of the invention similar to the asphalt plant of FIG. 12 but with provisions for total control of both primary and secondary combustion air. DETAILED DESCRIPTION OF THE INVENTION [0050] Referring now to the drawings in greater detail, attention is first directed a modern day counter-flow asphalt plant as shown in the prior art illustration of FIG. 1 for the purpose of subsequently comparing and contrasting the structure and operation of an asphalt plant constructed in accordance with this invention as illustrated in FIGS. 2-13 . The prior art asphalt plant of FIG. 1 is shown and described in greater detail in Hawkins U.S. Pat. No. 4,787,938 incorporated herein by reference. [0051] The prior art counter-flow plant includes a substantially horizontal, single drum mixer 10 carried by a ground engaging support frame 12 at a slight angle of declination, typically about 5 degrees. Mounted on the frame 12 are two pairs of large, motor driven rollers 14 which supportingly receive trunnion rings 16 secured to the exterior surface of the drum mixer 10 . Thus, rotation of the drive rollers 14 engaging the trunnion rings 16 causes the drum mixer 10 to be rotated about its central longitudinal axis in the direction of the rotational arrow 17 . [0052] Located at the inlet or upstream end of the drum mixer 10 is an aggregate feeder 18 to deliver aggregate to the interior of the drum mixer 10 from a storage hopper or stockpile (not shown). The inlet end of the drum mixer 10 is closed by a flanged exhaust port 20 leading to conventional air pollution control equipment (not shown), such as a baghouse, to remove particulates from the gas stream. [0053] Located at the outlet end of the drum mixer 10 is a discharge housing 22 to direct asphaltic composition from the drum mixer 10 to a material conveyor (not shown) for delivery of the final product to a storage bin or transporting vehicle. [0054] A combustion assembly 24 extends through the discharge housing 22 and into the drum mixer 10 to deliver fuel, primary air from a blower 26 and induced secondary air through an open annulus to a burner head 28 . In the combustion zone beginning at the burner head 28 there is generated a hot gas stream which flows through the drying zone of the drum mixer 10 . Within the drying zone are fixed various types of dryer flights or paddles 29 for the alternative purposes of lifting, tumbling, cascading, veiling, mixing, and moving aggregate within the drum mixer 10 to facilitate the drying and heating of the aggregate therein. Within the combustion zone, on the other hand, the combustion flights 30 are designed primarily to mix and move the aggregate through this section of the drum mixer rather than cause material to cascade or veil through the flame envelope. [0055] Downstream of the burner head 28 in a modern, prior art asphalt plant begins the mixing zone. Within this region is typically located the recycle feed assembly 34 by which recycle asphalt material may be introduced into the drum mixer 10 . A stationary box channel 35 encircles the exterior surface of the drum mixer 10 and includes a feed hopper 36 providing access to the interior of the box channel 35 . Bolted to the side walls of the box channel 35 are flexible seals 37 to permit rotation of the drum mixer 10 within the encircling box channel 35 . Secured to the outer wall of the drum mixer 10 and projecting into the space defined by the box channel 35 are a plurality of scoops 38 radially spaced around the drum mixer 10 . At the bottom of each scoop 38 is a scoop opening 40 through the wall of the drum mixer 10 to provide access to the interior of drum mixer 10 . Thus, recycle asphalt material may be delivered by conveyor (not shown) through the feed hopper 36 , into the box channel 35 and subsequently introduced into the interior of the drum mixer 10 through the scoop openings 40 . [0056] Mounted on the interior of the drum mixer 10 and within the mixing zone are staggered rows of sawtooth mixer flighting 42 to mix and stir material within the annulus of the drum mixer 10 and combustion assembly 24 . A conveyer or screw auger 44 extends into the drum mixer 10 for feeding binder material or mineral “fines” to the mixing zone. Likewise extending into the drum mixer 10 is an injection tube 46 for spraying liquid asphalt into the mixing zone. At the end of the mixing zone is located the discharge housing 22 as previously discussed through which the asphaltic product is discharged. [0057] With the foregoing background in mind, attention is now directed to the counter-flow asphalt plant constructed in accordance with a first preferred embodiment of this invention as illustrated in FIGS. 2-10 . As an overview, it should be noted that the inventive features taught herein may be adapted to a variety of asphalt plant equipment configurations. FIGS. 11-13 illustrate modifications of the mixing zone in accordance with the teachings of this invention. [0058] Turning then to the asphalt plant configuration shown in FIGS. 2-4 , the counter-flow plant includes a substantially horizontal, single cylindrical drum 50 carried by a ground engaging support frame 52 at a slight angle of declination, typically about 5 degrees. Mounted on the frame 52 are two pairs of large, motor driven rollers 54 which supportingly receive trunnion rings 56 secured to the exterior surface of the drum 50 . Thus, rotation of the drive rollers 54 engaging the trunnion rings 56 causes the drum 50 to be rotated about its central longitudinal axis. [0059] Located at the inlet or upstream end of the drum 50 is an aggregate feeder 58 to deliver aggregate to the interior of the drum 50 from a storage hopper or stockpile (not shown). The inlet end of the drum 50 is closed by a flanged exhaust port 59 connected, as is schematically illustrated in FIG. 3 , to ductwork 60 leading to conventional air pollution control equipment 61 , such as a baghouse, to remove particulates from the exhaust gas stream. [0060] Located at the outlet end of the drum 50 is a discharge housing 62 to direct asphaltic composition from the drum 50 to a material conveyor (not shown) for delivery of the final product to a storage bin or transporting vehicle. [0061] A combustion assembly 64 extends through the discharge housing 62 and into the drum 50 to deliver fuel through fuel line 65 and primary air from a blower 66 to a burner head 68 . Combustion of the air and fuel within the combustion zone of the drum 50 which generally extends from the burner head 68 to the end of the flame envelope 69 generates a hot gas stream which flows through the drying zone of the drum 50 . Within the drying zone, material flights 70 are secured to the interior surface of the drum 50 to lift, tumble, cascade, veil, mix, and release aggregate material within the drum 50 to create a substantially continuous veil or curtain of falling material through which the hot gas stream passes in counter current flow to facilitate the drying and heating of the aggregate. [0062] Conventional wisdom of asphalt plant design and operation positions the recycle feed downstream of the burner head as illustrated in FIG. 1 in order to deliver the RAP to the isolated mixing zone. Even if the recycle feed is positioned ahead of the burner, prior art asphalt plants add the RAP to an inner shell or with special flighting that shield the recycle material from the flame envelope. After preheating in this manner, the RAP is then delivered to the isolated mixing zone. The present design departs significantly from conventional wisdom in two important ways. First, the recycle feed assembly 72 is located upstream from the burner head 68 and intermediate the ends of the combustion zone, and secondly, the recycle material is introduced and exposed directly to the flame envelope within the combustion zone. [0063] The details of construction of the recycle feed assembly are shown in FIGS. 5-7 . A stationary box channel 75 is supported by legs 75 a to encircle the exterior surface of the drum 50 . A feed hopper 76 provides access to the interior of the box channel 75 . Bolted to the side walls of the box channel 75 are flexible seals 77 to permit rotation of the drum 50 within the encircling box channel 75 . Thus, for example, recycle asphalt material may be delivered by conveyor (not shown) through the feed hopper 76 , into the box channel 75 and subsequently introduced into the interior of the drum 50 through scoop openings 78 in the drum shell. [0064] Within the combustion zone are mounted a plurality of combustion flights that are designated generally by the numeral 80 . In contradiction to the teachings of the prior art, the combustion flights are constructed and arranged to deliver the recycle material into the combustion zone for direct exposure to the radiant heat of the flame envelope. Details of the combustion flighting is shown in FIGS. 6-8 . [0065] Referring first to FIG. 6 , the plurality of circumferential openings 78 through the shell of the drum are registered with the box channel 75 . Scoop plates 82 are secured exteriorly of the drum shell 50 to frame three sides of each such opening 78 to direct material falling through the feed hopper 76 from the interior of the box channel 75 through an opening 78 into the interior of the drum shell 50 . Note that a set of scoop plates 82 framing any opening 78 form a mouth which is open in the direction of rotation of the drum 50 as indicated by the arrow 84 ( FIG. 7 ). [0066] Secured to the interior surface of the drum shell 50 in the combustion zone, substantially parallel to the rotational axis of the drum, are the combustion flights 80 . Each combustion flight 80 includes an elongate flighting web 88 which has an angled leading lip 88 a bent with respect to the main body portion 88 b , and an angled trailing lip 88 c directed interiorly of the drum 50 from the main body portion 88 b . The leading lip 88 a of each flighting web 88 is connected to the interior surface of the drum 50 . As best shown in FIG. 8 , the trailing lip 88 c of one flighting web 88 is held apart from the nearest adjacent flighting web 88 by a plurality of clip brackets 90 spaced longitudinally along the length of the flighting web 88 . For each such clip bracket 90 , a pin 92 interconnects the trailing lip 88 c to the clip bracket 90 and then to the main body portion 88 b of the adjacent flighting web 88 . Thus, the trailing lip 88 c of one flighting web 88 overlies the leading lip 88 a of the next adjacent flighting web 88 and is held apart by the clip brackets 90 and pins 92 to provide an elongate slot opening between successive webs 80 . [0067] Accordingly, as illustrated by the material flow arrows of FIG. 7 , recycle materials delivered through the feed hopper 76 are directed by the scoop plates 82 through the openings 78 in the drum shell 50 , then through the slots formed between successive combustion flighting webs 88 and into the combustion zone for direct exposure to radiant heat of the flame envelope. Since the RAP experiences radiant, convective and conductive heat transfer, it is important to limit the residence time of the RAP within the combustion zone. For this reason, the distance between the recycle feed assembly 72 and the mixing zone is limited to a range of 2 to 8 feet, and preferably falls in the range of 3 to 5 feet. Any blue smoke generated as a result of operation in this manner can be incinerated in the flame envelope 69 . [0068] Downstream of the burner head 68 is the mixing zone within the drum 50 which is separated from the combustion zone by a transition member as shown in FIG. 9 and designated generally by the numeral 94 . The transition piece 94 includes an annular collar 96 secured to the interior wall of the drum shell 50 . The collar 96 includes radially spaced openings 98 around the periphery of the collar at the drum shell 50 to permit aggregate and RAP material to pass from the combustion zone to the mixing zone. Secured adjacent the inside diameter of the collar 96 is a frusto-conical venturi 100 which is concentrically aligned with the longitudinal axis of the drum 60 and which uniformly tapers from a larger diameter at the collar 96 to a smaller diameter in the direction toward the combustion and drying zones. The venture 100 terminates proximate the burner head 68 for the purpose, as will be seen, of channeling secondary combustion air, blue smoke and steam from the mixing zone into the flame envelope 69 within the combustion zone. [0069] The mixing zone of the present invention is operationally subdivided into two subzones or stages which can most conveniently be thought of as a first region wherein liquid asphalt is added to the aggregate and RAP materials, and a second region wherein the final product components of binder dust or mineral “fines” are added to the mixture of aggregate, RAP and liquid asphalt. Therefore, the first stage of the mixing zone extends generally from the combustion zone to point where fines are added, and the second stage of the mixing zone extends generally from the point where fines are added to the discharge of the final product. [0070] Throughout the mixing zone and mounted to the interior of the drum shell 50 are rows of mixer flighting 102 to mix and stir material within the annulus formed generally between the drum 50 and combustion assembly 64 . Through the rear wall of the discharge housing 62 extends an injection tube 104 for spraying liquid asphalt into the first stage of the mixing zone. Thus, the spray head 106 of the injection tube 104 is positioned just downstream of the transition piece 94 . [0071] Closer to the product discharge, a screw auger 108 extends through the rear wall of the discharge housing 62 . Typically, a screw auger is a hollow pipe in which a spiral flight is rotated to carry material through the pipe and out one end. Screw auger 108 of this invention is atypical. From the discharge end and along a length of the auger pipe are a plurality of elongate slots 109 in the bottom of the pipe to permit the discharge of dust and fines along a substantial length of the auger 108 when the spiral flight is rotated within the auger pipe. Moreover, mounted to the auger pipe 108 along opposite sides of the discharge slots therein are a pair of spaced apart, flexible flaps 110 which hang downwardly from the auger 108 into the mixing zone as shown in FIG. 10 . The foregoing features result in better mixing of the fines into the final product and minimize entrainment of the fines into the air of the mixing zone. [0072] As shown in FIGS. 3 & 10 , a stationary teepee housing 112 is mounted within the mixing zone, generally above the combustion assembly 64 to shield same from any sticky asphaltic composition that might fall from above while the material components are mixed within the mixing zone and to assist in isolating the second stage of the mixing zone where the dust and fines are added to the mix. The teepee housing is substantially sealed against the rear wall of the discharge housing 62 . Above the teepee housing 112 , a secondary combustion air inlet 114 penetrates the discharge housing 62 to permit the free flow of air into the mixing zone above the teepee housing 112 . The air inlet 114 may be optionally fitted with a damper to partially regulate air flow through the inlet 114 . [0073] During plant operations, combustion at the burner head 68 is principally supported by the fuel and primary air, but secondary combustion air is introduced through the inlet 114 and eventually reaches the burner head 68 to also support combustion. As a result of the arrangement of the features previously described, the second stage of the mixing zone is unaffected by the flow of secondary combustion air. In other words, the region of the second stage of the mixing zone where the dust and fines are added is substantially isolated from air flow by location, the teepee housing 112 , and the flexible flaps 110 of the screw auger 108 . On the other hand, the first stage of the mixing zone where the liquid asphalt is added and where blue smoke and steam may be present are effectively swept by the secondary combustion air into the combustion zone so that the blue smoke can be incinerated by the flame envelope 69 . Thus, dust entrainment in the mixing zone is minimized and any blue smoke and steam is evacuated to the combustion zone rather than being discharged with the final product. [0074] Unlike conventional counter-flow asphalt plants, the asphalt plant of this invention optionally includes an exhaust gas burner. Attention is now directed to the upstream portion of FIG. 3 and the end view of FIG. 4 . A second combustion assembly 120 extends through the exhaust port housing 59 and into the exhaust gas stream to deliver fuel through supply line 122 and primary air from a blower 124 to a burner head 126 . Combustion at the burner head 126 heats the exhaust gas stream to elevate the temperature thereof before delivery to the baghouse 61 . It is desirable to maintain the temperature of the exhaust gas stream at or above its dew point prior to entry to the air pollution filtration equipment 61 . More or less energy may be supplied to the exhaust gas stream by process control equipment known to those skilled in the art. Illustrated in the drawings is a schematic representation of one example which includes a temperature sensing thermocouple 128 installed in the exhaust port housing 59 or ductwork 60 of the baghouse 61 . The thermocouple 128 is operatively connected to a process controller 130 which, in turn, is connected to the combustion assembly 120 for regulation of the fuel and air supply to support combustion in the exhaust gas stream. [0075] FIG. 11 shows a single drum, counter-flow asphalt plant constructed in accordance with a second preferred embodiment of the invention that is similar to the asphalt plant of FIGS. 3-10 but with provisions for total control of both primary and secondary combustion air. In general, the structural details of the FIGS. 3-10 and FIG. 11 plants are the same except for the provision of secondary air to the mixing zone. Instead of the secondary air inlet 114 and the operationally free flow of secondary air as in the FIGS. 3-10 configuration, the discharge housing 62 in FIG. 11 is fitted above the teepee structure 112 with a secondary air blower 132 to forcibly deliver secondary combustion air to the mixing zone. The effect of the secondary air flow is essentially the same as the previous description. In other words, the region of the second stage of the mixing zone where the dust and fines are added is substantially isolated from air flow by location, the teepee housing 112 , and the flexible flaps 110 of the screw auger 108 . On the other hand, the first stage of the mixing zone where the liquid asphalt is added and where blue smoke and steam may be present are effectively swept by the secondary combustion air into the combustion zone so that the blue smoke can be incinerated by the flame envelope 69 . Thus, dust entrainment in the mixing zone is minimized and any blue smoke and steam is positively evacuated to the combustion zone rather than being discharged with the final product. [0076] FIG. 12 shows a single drum, counter-flow asphalt plant constructed in accordance with a third preferred embodiment of the invention that is similar to the two previous embodiments but with a modified mixing zone and aspirated secondary combustion air. Comparing the plant of FIG. 3 with that of FIG. 12 , the teepee housing 112 and air inlet 114 are absent but the remaining features are the same. In FIG. 12 , a large diameter secondary air tube 136 extends through the discharge housing 62 into the mixing zone. The tube 136 terminates intermediate the asphalt spray head 106 and the auger 108 to better define the transition between the first and second stages of the mixing zone. The combustion assembly 64 extends through the tube 136 and forms an open annulus therewith through which ambient air flow is induced during combustion operations. [0077] As shown, the secondary air tube 136 also serves to shield the combustion assembly 64 from any sticky asphaltic composition that might fall from above while the material components are mixed within the mixing zone and to effectively isolate the second stage of the mixing zone where the dust and fines are added to the mix. [0078] During plant operations, combustion at the burner head 68 is principally supported by the fuel and primary air, but secondary combustion air is introduced through the tube 136 and eventually reaches the burner head 68 to also support combustion. As a result of the arrangement of the features previously described, the second stage of the mixing zone is unaffected by the flow of secondary combustion air. In other words, the region of the mixing zone where the dust and fines are added is substantially isolated from air flow by location, the secondary air tube 136 , and the flexible flaps 110 of the screw auger 108 . On the other hand, the first stage of the mixing zone where the liquid asphalt is added and where blue smoke and steam may be present are effectively swept by the secondary combustion air into the combustion zone so that the blue smoke can be incinerated by the flame envelope 69 . Thus, dust entrainment in the mixing zone is minimized and any blue smoke and steam is evacuated to the combustion zone rather than being discharged with the final product. [0079] FIG. 13 shows a single drum, counter-flow asphalt plant constructed in accordance with a fourth preferred embodiment of the invention similar to the asphalt plant of FIG. 12 but with provisions for total control of both primary and secondary combustion air. Here, the secondary air tube 136 is connected to a positive displacement blower 140 with separate controls to provide and independently regulate both primary and secondary air. Otherwise, the internals of the drum 50 are the same as described with reference to FIG. 12 . [0080] The foregoing features of the invention both individually and in combination offer remarkable benefits to modern asphalt plant design, construction and operations. RAP material is introduced directly into the hottest area of the drum and directly exposed to radiant heat of the flame envelope. High percentage RAP mixes (up to 50%) are now possible without excessive equipment shell temperatures or excessive exhaust gas temperatures. The limited residence time in the combustion zone generally keeps the RAP below the smoke point, but any blue smoke formed in the combustion zone can still be incinerated without passing into the baghouse because the feed entry is positioned intermediate the ends of the combustion zone. [0081] The recycle feed assembly can also be used to introduce both RAP material, virgin material or a combination of both in order to reduce NO X emissions. This is achieved by introducing the wet materials (RAP or virgin) at the hot part of the combustion zone. The steam produced by the moisture laden material acts to cool the combustion zone hereby reducing the formation of thermally produced NO X . [0082] Provision of a secondary burner for the exhaust gas stream permits precision control of the exhaust gas temperatures for maximum fuel efficiency. Equipment life is extended by eliminating the need to superheat virgin aggregates. Highly efficient heat transfer in the heating/drying zone of asphalt plant permits operations with the gas in the drying zone to sink as low as 180° F. with energy addition prior to delivery of the gas to the baghouse at or above its dew point in the range of 225° F. The plant operator can now standardize on the use of use of polyester bags (275° F. maximum service) rather than NOMEX (375° F. maximum service) bags to achieve a cost reduction of approximately 80%. [0083] Likewise, the features of this invention alternatively permit either increased production or decreased sizes of the equipment required for a given production rate because both the BTU and CFM requirements are reduced as a result of the lower stack temperature. These highly significant advantages and benefits can be understood with reference to the following sizing calculations table. SIZING CALCULATIONS TABLE Calculation Assumptions: Counter-flow Drum, 650′ Elevation, #2 Fuel Oil, 5% Moisture, 320° F. Mix, 900 FPM Drum Throughput, 3500 FPM Inlet Duct, 4400 FPM Stack TPH BTU'S × 1,000,000 DRYER DIA. INLET DUCT DIA. BAGHOUSE SIZE STACK DIA. 375 DEGREE STACK: 200 55.91  87.5″ 44.5″ 37,500 ACFM 39.5″ 300 83.87   107″ 54.25″  56,200 ACFM 48.5″ 400 111.83 123.5″ 62.75″  74,900 ACFM   56″ 500 139.79   138″   70″ 93,600 ACFM 62.5″ 600 167.74 151.5″ 76.75″  112,400 ACFM  68.5″ 300 DEGREE STACK: 200 53.25   82″ 41.5″ 33,000 ACFM   37″ 300 79.87 100.5″   51″ 49,500 ACFM 45.5″ 400 106.49   116″ 58.75″  65,900 ACFM 52.5″ 500 133.12 129.5″ 65.75″  82,400 ACFM 58.5″ 600 159.74   142″   72″ 98,900 ACFM   64″ 225 DEGREE STACK: 180 DEGREES DRYER EXHAUST GAS TEMPERATURE: 200 50.74  73.5″   39″ 28,800 ACFM 34.75″  300 76.11 89.75″ 47.5″ 43,100 ACFM 42.5″ 400 101.48 103.5″   55″ 57,500 ACFM   49″ 500 126.85 115.75″  61.5″ 71,900 ACFM 54.75″  600 152.22   127″   67″ 86,200 ACFM   60″ [0084] By utilizing both the unique combustion entry RAP system combined with a dual burner configuration, in the example of a 50% recycle plant, such a system has a reduced size of the air handling equipment, including the dust collection system, by 20%, and the combustion equipment by 10%. [0085] The size of the typical 400 ton per hour drum/dryer, for example, goes from 10′-3″ diameter to 8′-8″ diameter. The size of the baghouse filter collector on the same plant goes from a 75,000 ACFM capacity requirement to a 57,500 ACFM requirement. The size of the burner goes from 112 million BTU down to 101 million BTU. Such savings are heretofore unknown for modern asphalt plants. [0086] From the foregoing it will be seen that this invention is one well adapted to attain all the ends and objects hereinabove set forth, together with the other advantages which are obvious and which are inherent to the invention. [0087] It will be understood that certain features and subcombinations are of utility and may be employed without reference to other features and subcombinations. This is contemplated by and is within the scope of the claims. [0088] Since many possible embodiments may be made of the invention without departing from the scope thereof, it is understood that all matter herein set forth or shown in the accompanying drawings is to be interpreted as illustrative and not in a limiting sense. NUMERALS [0000] Prior Art [0000] drum mixer 10 support frame 12 motor driven rollers 14 trunnion rings 16 rotational arrow 17 aggregate feeder 18 exhaust port 20 discharge housing 22 combustion assembly 24 blower 26 burner head 28 dryer flights 29 combustion flights 30 recycle feed assembly 34 stationary box channel 35 feed hopper 36 flexible seals 37 scoops 38 scoop opening 40 sawtooth flighting 42 screw auger 44 injection tube 46 Invention cylindrical drum 50 support frame 52 drive rollers 54 trunnion rings 56 aggregate feeder 58 exhaust port 59 ductwork 60 air pollution control equipment 61 discharge housing 62 combustion assembly 64 fuel line 65 blower 66 burner head 68 flame envelope 69 dryer flights 70 recycle feed assembly 72 box channel 75 support legs 75 a feed hopper 76 flexible seals 77 scoop openings 78 combustion flighting 80 scoop plates 82 rotational arrow 84 flighting web 88 angled leading lip 88 a main body portion 88 b angles trailing lip 88 c clip bracket 90 pin 92 transition member 94 annular collar 96 radially spaced openings 98 venturi 100 mixer flighting 102 injection tube 104 spray head 106 screw auger 108 elongate slots 109 flexible flaps 110 teepee housing 112 secondary combustion air inlet 114 secondary combustion assembly 120 fuel supply line 122 blower 124 burner head 126 thermocouple 128 process controller 130 FIG. 11 secondary air blower 132 FIG. 12 secondary air tube 136 FIG. 13 positive displacement blower 140

A counter-flow drum mixer asphalt plant equipped with a secondary feeder for introducing RAP to direct radiant heat of the combustion zone. Heated virgin aggregate and RAP in the combustion zone are delivered through a transition piece to a first stage of the mixing zone where liquid asphalt is combined with the materials and secondary combustion air flows through the first stage to evacuate blue smoke and steam back to the combustion zone. The second stage of the mixing zone is substantially isolated from secondary combustion air flow where dust and mineral fines are introduced and mixed to complete the asphalt product discharged from the mixing zone. Alternative constructions of the mixing zone are disclosed to provide the first and second stages having such characteristics, as well as options for both the passive and active control of the secondary combustion air. An optional secondary burner in the exhaust housing elevates the temperature of the exhaust gas above its dew point temperature before delivery to the baghouse.

RELATED APPLICATIONS This application is related to co-pending commonly assigned application Ser. No. 09/123,371 entitled VARIABLE GAIN IMAGE INTENSIFIER, filed on Jul. 27, 1998, and application Ser. No. 09/074,238 entitled IMPROVED MONOCULAR NIGHT VISION DEVICE, filed on May 7, 1998 now U.S. Pat. No. 6,071,639 and assigned to IT Manufacturing Enterprises, the assignee herein. FIELD OF THE INVENTION This invention relates generally to electronic circuits and in particular to an electronic circuit including a flexible printed circuit board and a rigid printed circuit board incorporated into a monocular night vision device for electronically connecting components within the lower and upper housing improved night vision operation. BACKGROUND OF THE INVENTION A monocular night vision system basically incorporates a single eyepiece lens assembly, image intensifier assembly, and objective lens assembly. Most monocular night vision devices (MNVDs) are compact and lightweight to optimize hand-held use. MNVDS are often referred to as pocket scopes since they could optimally be small enough to be stored in a user's pockets. Numerous MNVDs exist in the prior art. Examples of some of these night vision devices, including hand-held night vision devices, include U.S. patent application Ser. No. 08/108,989 entitled NIGHT VISION MONOCULARS, filed Aug. 18, 1993; U.S. patent application Ser. No. 08/405,172 entitled COMPACT NIGHT VISION DEVICE, filed Mar. 16, 1995; U.S. Pat. No. 5,644,425, issued Jul. 1, 1997, entitled NIGHT VISION MONOCULAR WITH UNISTRUCTURAL OPTICAL BED also teaches a hand-held night vision device for use in both military and non-military applications, however these devices generally suffer from a combination of poor performance characteristics and design shortcomings which lead to inefficient device operation or limited flexibility, and poor performance. For example, a number of the monocular night vision devices have main housings which are made of metallic material which make them rugged, but heavy. Moreover, prior art MNVDs are often bulky and uncomfortable to hold in one's hand and are difficult to operate when deployed in completely dark areas. Furthermore, prior art MNVDs are often energy efficient, expending battery power even when not in use, such as during daylight. In the event of a headmounted device, prior art MNVDs did not automatically turn off when removed from the helmet mount or when flipped up in the helmet mount. Still further, prior art devices could not be mounted to an M16/M4 receiver rail configured for the Modular Weapon System Kit (which fits the mounting rail defined in MIL-STD-93), and standard AN/PVS-7 accessories such as the lens cap, sacrificial filter, compass, 3X magnifier, and light interference filter could not be attached to the objective lens assembly of these devices. As one can ascertain, night vision systems frequently need to include some control functions beyond just “on” and “off”. Users commonly want additional features such as: a low-battery indicator, an infrared illuminator for use in very dark areas, an indicator that the infrared illuminator is activated, an automatic cut-off in high-light conditions, an automatic cut-off when the viewing device is flipped up to a stowed position or removed from its mount, and a variable gain control. These features can be implemented piecemeal, or as parts of an integrated control system. The prior art AN/PVS-7 night vision device, manufactured by IT Corporation, the assignee herein, represents an integrated control system device. The AN/PVS-7 is a binocular viewer having one objective lens, one image intensifier tube, and two eyepieces which view the same output image from the tube via an arrangement of a beam splitter and turning mirrors. The AN/PVS-7 is intended predominantly for use by military ground forces, and can be hand-held or attached to a head mount or helmet mount. The AN/PVS-7 includes a control circuit which is an application-specific integrated circuit (ASIC), implemented in a complementary metal-oxide semiconductor (CMOS) process, and including both digital and analog subcircuits. This ASIC includes a high-light cutoff circuit described in commonly assigned U.S. Pat. No. 4,843,29, entitled HIGH LIGHT LEVEL CUTOFF APPARATUS FOR USE WITH NIGHT VISION DEVICE, issued to J. Reed and J. Caserta, and incorporated herein by reference. FIG. 6 shows the prior art circuit illustrated in the above patent (FIG. 2 of U.S. Pat. No. 4,843,229) where most of the functional blocks shown are contained in the ASIC. Only the light sensor 8 , the crystal 22 , the voltage multiplier 4 , the power field-effect transistor (FET) 3 , the battery 1 , the goggles (intensifier tube) 2 , and the on/off switch are not located inside the ASIC, due to their unsuitability for implementation in the CMOS process. The crystal 22 may be replaced by a resistor-capacitor (RC) timing network, in order to reduce cost while still providing sufficient timing accuracy. This ASIC also includes circuitry to implement a flashing low-battery indicator and flip-up cutoff. In the AN/PVS-7, the ASIC and its associated electronic parts, including the voltage multiplier 4 , the power FET 3 , RC timing network, and some associated power filtering components are assembled on one small surface-mount rigid printed circuit board or ceramic substrate. Other parts, including the on/off/ir switch, the connections for the intensifier tube, the light sensor (photo resistor or photo transistor), the infrared illuminator, the low battery indicator light-emitting diode (LED), the infrared indicator LED, and the magnetic reed switch (which is the sensor for the flip-up cutoff function) are required to be located elsewhere in the overall housing, due to physical access or optical exposure requirements. These parts are interconnected to the main circuit via a flexible polyamide circuit with etched copper conductors. The battery contacts are connected by wires to the rest of the circuit. The flip-up cutoff feature assures that the user does not inadvertently leave the viewing device on or give away his position by exposing the glow from the intensifier, when the viewing device is removed from its mount or is flipped up to the stowed position. The flip-up cutoff feature functions as follows. The magnetic reed switch is placed in the AN/PVS-7 viewing device housing, inside the housing wall which is in proximity to the mounting point. The magnetic reed switch is a single-pole, double-throw device. In the de-energized (no magnetic field applied) state, the magnetic reed switch connects an input of the ASIC to the positive supply voltage considered logic “high”. In the energized (magnetic field applied) state, the magnetic reed switch connects the input of the ASIC to the negative supply voltage. This is considered logic “low”. A small magnet is placed in the head mount and helmet mount, in a location proximal to the mounting point for the viewing device. When the viewing device is installed in the mount, the magnetic reed switch comes in proximity to the magnet, the reed switch is energized, and the ASIC input transits from a logic high state to a logic low state, provided the viewing device has been turned on. The ASIC contains logic which ignores the reed switch state at the moment when the viewing device is turned on, and also ignores high-to-low transitions of the input from the reed switch. Thus, the viewing device can be switched on whether or not it is in the mount, and the viewing device will not turn off when it is installed in the mount. When the viewing device is removed from the mount or flipped up to the stowed position in the mount, the magnetic reed switch is separated from proximity to the magnet. The reed switch is thus de-energized, and the ASIC input transits from a logic low state to a logic high state, (provided the viewing device has been turned on). The transition from low to high is interpreted by the logic in the ASIC as a command to turn the intensifier off, causing the latching flip-flop 7 to close, grounding the gate electrode of the power FET 3 . The power FET 3 ceases to conduct, turning off the intensifier and turning off the infrared illuminator and indicator, if on. Once the ASIC turns the intensifier off, the user must switch the viewing off and back on to restore the operation of the intensifier. The low battery indicator provides a visual warning to the user that the battery is in need of replacement, prior to the time when the intensifier would fail due to lack of sufficient operating voltage. The low battery indicator circuit in the ASIC makes use of the voltage reference 10 and an additional comparator like the comparator 9 . The battery voltage is fed through a voltage divider resistor pair in the ASIC to an input of the additional comparator. The other input of the comparator is fed by the voltage reference 10 . When the divided battery voltage falls below the level of the reference voltage, the comparator causes intermediate outputs from the counter 20 to be combined to form a pulsing current waveform that flashes the low battery indicator LED. The flashes from the LED are visible through a small hole in the turning mirror associated with the eyepiece for the user's right eye. The tap at the junction of the divider resistor pair in the ASIC is connected to an input of the ASIC. This input makes is possible to adjust the voltage threshold at which the low battery indicator begins to flash. The tap of a divider resistor pair or potentiometer external to the ASIC is connected to the ASIC input. Trimming either of the divider resistors or adjusting the potentiometer changes the voltage threshold, and enables the threshold to be precisely set to the desired value regardless of manufacturing variations in the ASIC. The infrared (ir) illuminator enables the user to illuminate a very dark area with infrared illumination which the image intensifier can “see”, but which is invisible to the human eye. The illuminator comprises an infrared emitter diode which is mounted in an aperture in the AN/PVS-7 housing, and is aimed forward to illuminate the field of view of the intensifier. In addition to the illuminator a visible LED serves as an infrared indicator to warn the user that the infrared illuminator is in use. In similar fashion to the low battery indicator LED, the infrared indicator LED is visible through a small hole in the turning mirror associated with the eyepiece for a user's eye. The infrared illuminator and infrared indicator are switched on via the third position on the off/on/ir switch. The user can activate ir momentarily by rotating the switch knob to the ir position, or can activate ir continuously by pulling and rotating the switch knob to the ir position. The ir position on the switch applies battery power to the ir illuminator, ir indicator, as well as to the intensifier and associated circuits. The power returns for the ir illuminator, ir indicator, and intensifier are through the power switching FET 3 so that the high light cutoff and flip-up cutoff circuits can deactivate these functions. However, a number of problems associated with prior art night vision devices currently exist. Such problems include the lack of a variable gain feature, and a night vision device operable in a small, lightweight package, such as a monocular. The monocular enables the user to keep one eye dark-adapted for a wide-field view, while using the monocular with the other eye to see specific details, even in shaded areas. The variable gain feature allows the user to maintain partial dark-adaptation, if desired, in the eye using the intensifier, and allows the user to defeat the automatic brightness control function in the intensifier, which some users find to be annoying. The reduced size and weight of a monocular, as compared to a binocular, improves the maneuverability of the user, and reduces fatigue. The flexibility of the monocular to be mounted to a rifle, as well as to be mounted to the head or helmet and used with either eye, as well as to be used hand-held, expands its utility for the user. Further, in systems which have interchangeable tubes and variable gain, it is preferable that any tube be capable of installation in any system and yet retain the same maximum and minimum gain limits, with no adjustment of limits required. The ability to replace or interchange tubes without requiring gain limit adjustments means that maintainers can do their work faster and with less support equipment, reducing maintenance costs. The monocular device according to the present invention eliminates the size and weight associated with the mounting adapter, output optical splitter, image erector, and mirrors associated with the bi-ocular viewer. In addition, this monocular capitalizes on the small size and light weight of the MX-10160 image intensifier tube, as compared to the larger MX-10130 tube used in the AN/PVS-7 system. The monocular features are described in more detail in a commonly assigned related patent application, entitled IMPROVED MONOCULAR NIGHT VISION DEVICE, and incorporated herein by reference. The MX-10160 tube is modified to include the ability for the user to adjust the intensifier's gain to any desired value between specified upper and lower limits, which can be factory-preset. The factory-preset tubes are interchangeable in monoculars, without requiring the maintainers to adjust the preset gain settings. The variable gain tube is described in more detail in a related patent application, entitled VARIABLE GAIN IMAGE INTENSIFIER, and also incorporated by reference. According to the present invention, a novel electronic circuit to be used in conjunction with the monocular makes use of the items previously developed for the AN/PVS-7, and adds provisions for variable gain, without requiring the maintainers to adjust the monocular circuit when replacing the intensifier tube. In addition, the novel circuit achieves reduced size and improved producibility by including all functions, except for the switches, batteries, and gain control, on one rigid printed circuit board (pcb). The switches, batteries, and gain control are interconnected by a single flexible pcb which interconnects to the rigid pcb. This approach eliminates hand wiring, enables simplified, quicker assembly, and improves reliability by eliminating wire joints which can be prone to flexural fatigue failure or short circuits caused by loose strands. To reduce size and weight of the monocular, the head/helmet mount adapter is made part of a detachable mounting arm. Such a feature imposes additional requirements on the circuit, as the magnetic reed switch does not reside in the main housing, but is now in a detachable mounting arm. The circuit includes features for enabling the detachment while protecting from damage and preventing inadvertent turn-off during the periods when the mounting arm is detached. In this invention, components and features are added to the flip-up cutoff circuit to harmlessly absorb any electrostatic discharges (esd) to the contacts and to prevent unintended turn-off events. In the present invention, the flip-up cutoff circuit contacts on the monocular housing are recessed slightly below the mounting surface to protect the contacts from mechanical damage and to prevent electrical contact to a small arms mounting adapter, which does not include a flip-up cutoff function. Further, the number of connections to the reed switch is reduced from three to two, and new filtering provisions have been added to prevent magnetic reed switch bounce from causing unintended turn-off events. SUMMARY OF THE INVENTION It is an object of the present invention to provide an electronic circuit for use in a monocular night vision device for electronically controlling a plurality of components within the device, the device having an objective lens assembly for receiving low intensity light, an image intensifier assembly comprising a variable gain image intensifier tube having a user-adjustable variable gain controller external to the tube for adjusting the light intensity level of a visible output image, a single eyepiece lens assembly for viewing the output image from the image intensifier assembly; and a non-metallic housing comprising an upper housing for receiving the objective lens assembly, image intensifier assembly, and eyepiece lens assembly, and a lower housing containing a battery cavity for receiving at least one battery to power the device, wherein the housing aligns the objective lens assembly with the image intensifier assembly and the eyepiece lens assembly along an optical axis, and wherein the upper and lower housing are coupled to one another along the optical axis, the electronic circuit comprising a rigid printed circuit board (pcb) located within the lower housing having a plurality of contacts for enabling electronic communication with a plurality of components mounted thereon and with the variable gain image intensifier tube, the rigid pcb including a pair of contacts in electrical communication with the image intensifier tube for energizing the intensifier tube; and a flexible printed circuit board flexibly coupled to the rigid pcb and adaptable to the geometry of the upper and lower housings for electronically interconnecting components located within the upper and lower housings with the rigid pcb, the flexible pcb having a first circuit connection to the image intensifier tube and a second circuit connection to an adjustable potentiometer mounted external to the image intensifier tube on the rigid pcb, the flexible pcb operative for coupling the adjustable gain potentiometer mounted external to the image intensifier tube to the rigid pcb via first and second connections. It is a further object of the present invention to provide in a monocular night vision device having an objective lens assembly for receiving low intensity light, an image intensifier assembly comprising an image intensifier tube, a single eyepiece lens assembly for viewing an output image from the image intensifier assembly, and a non-metallic housing comprising an upper housing for receiving the objective lens assembly, image intensifier assembly, and eyepiece lens assembly, and a lower housing containing a battery cavity for receiving at least one battery to power the device, wherein the housing aligns the objective lens assembly with the image intensifier assembly and the eyepiece lens assembly along an optical axis, and wherein the upper and lower housing are coupled to one another along the optical axis, an electronic circuit for electronically controlling said monocular device comprising a rigid printed circuit board (pcb) located in the lower housing having a plurality of electronic components mounted thereon and including an ASIC; a single flexible pcb connected to the rigid pcb at a plurality of predetermined contact points on the rigid pcb for coupling components located external to the rigid pcb with the rigid pcb; and interface means for electronically coupling a peripheral electronic assembly having a magnetic reed switch and a connecting circuit to the monocular night vision device. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view of the MNVD according to the present invention. FIG. 2 is an exploded view of the MNVD of FIG. 1 . FIG. 3 is an illustration of the variable gain image intensifier incorporated into the MNVD of the present invention. FIGS. 4A and 4B are top and bottom perspective views of the upper housing assembly. FIGS. 5A and 5B are top and bottom perspective views of the lower housing assembly. FIG. 6 is a block diagram of a prior art high light level cutoff apparatus having portions contained on an ASIC. FIG. 7 is an illustration of the battery spring assembly connectable to the flexible circuit according to the present invention. FIGS. 8A and 8B are top and bottom isometric views of the head/helmet mount adapter of the MNVD system. FIG. 9 is an illustration of the rotational movement of the MNVD head/helmet mount adapter. FIG. 10 is an illustration of the head/helmet mount adapter fastened to the MNVD of the present invention. FIG. 11 is an illustration of a small arms mounting adapter for attaching to the MNVD. FIG. 12 is a perspective view of the small arms adapter of FIG. 11 connected to the MNVD. FIGS. 13A-B are a schematic illustration of terminal connections associated with the electronic circuit board of the lower housing of the MNVD according to the present invention. FIGS. 14A and B show top and bottom views respectively of the rigid printed circuit board depicting the positional layout of components. FIG. 15 shows a pictorial isometric view of the flexible printed circuit board according to the present invention. FIG. 16 is a schematic illustrating the electrical connections external to the rigid electronic printed circuit board, as established by the flexible printed circuits. FIG. 17 is a schematic illustrating the electrical connections and components on the rigid electronic printed circuit board. DETAILED DESCRIPTION OF THE INVENTION Before embarking on a detailed discussion, the following should be understood. The circuit according to the present invention is operable within a night vision device, and preferably within a night vision monocular such as the AN/PVS-7 night vision monocular, as well as with the night vision device depicted in co-pending application Ser. No. 09/074,238 entitled IMPROVED MONOCULAR NIGHT VISION DEVICE, the details and operation of which are incorporated herein by reference. As such, a monocular night vision device incorporating the circuit of the present invention will be described with reference to the drawings. A monocular night vision device 10 according to the present invention is shown in FIG. 1 . This device 10 is compact, lightweight, and comfortably fits into a user's hand. The device can be hand held, head or helmet mounted, or mounted onto a weapon such as a rifle. These capabilities provide a versatile monocular night vision device with a wide variety of usage modes. FIG. 2 provides an exploded view of the elements comprising the MNVD 10 of FIG. 1 . Note that, when referring to the drawings, like parts are indicated using like reference numerals. Referring now to FIGS. 2 and 3, the MNVD 10 includes an image intensifier 20 (see FIG. 11) which has the same performance as a conventional MX-10160 intensifier, but provides the capability for the tube gain to be varied by the user. This is accomplished through an externally mounted adjustable potentiometer 28 . The image intensifier 20 is attached to a flexible printed circuit board (pcb) 25 with a four pin connector 27 positioned external to the cylindrical body 22 to provide power to the intensifier tube. A tube alignment pin 60 ensures proper alignment of the image intensifier tube with the upper housing. External Gain Control knob 99 extending from the front 85 of the lower housing allows a user to variably adjust the gain of the image intensifier tube 20 to the desired level for optimal performance. A conventional eyepiece lens assembly 30 , such as the AN/AVS-6 eyepiece lens, is incorporated into the monocular night vision device 10 . This eyepiece provides 25-mm eye relief which is optimal for use in weapon firing or with NBC (nuclear/biological/chemical) gear. An eyepiece adapter 30 A is attached to the rear of the eyepiece which allows for fastening an eyecup or eye guard and a demist shield 41 (FIG. 4 B). The monocular night vision device 10 further incorporates an objective cell assembly 40 comprising an objective lens assembly 42 and infinity focus stop ring 44 , having the same optics as a conventional AN/AVS-6 objective cell assembly. This allows for high optical performance of the device since distortion is minimized between the standard AN/AVS-6 eyepiece and objective optics. However, the optics of device 10 are packaged into a lens cell housing having the same external features and dimensions as the AN/PVS-7 lens cell housing. This allows for identical focus adjustment of the AN/PVS-7 and incorporation of the standard AN/PVS-7 objective focus knob and external cell threads for accepting standard AN/PVS-7 accessories. A close focus stop ring 45 is fastened to the inside of the objective cell lens assembly. As best shown in FIGS. 2, 4 , and 5 , the main body of the monocular night vision device 10 consists of an upper housing 50 and lower housing 70 . The upper and lower housings are separated along the optical axis of the system, such that upon assembly, the housings are coupled along said axis. The upper housing 50 , as shown in FIGS. 4A-B, holds the objective lens assembly 42 , image intensifier 20 , and eyepiece lens assembly 30 . The lower housing, as illustrated in FIGS. 5A-B, holds the electronics 76 and the battery cavity 80 . This design of a split upper and lower housing provides for ease of assembly and maintainability. As shown in FIG. 2, an o-ring 85 fits onto and engages oppositely disposed surfaces of the upper 50 and lower 70 housings to provide an environmental seal between the upper and lower housings. Referring again to FIG. 4A, two clear circular windows 52 are positioned on the front face 54 of the upper housing 50 . These windows align with an IRLED 72 A and photo transistor 72 B assembled onto a rigid printed circuit board within the lower housing (FIG. 5 A). The IRLED 72 A is activated by OFF/SYSTEM ON/MOMENTARY IR ON/LOCKED IR ON switch 91 via the electronics to provide forward projecting light for additional illumination. This is particularly useful for operations conducted in virtually total darkness. Photo transistor 72 B is operable to sense light intensity incident onto its window indicative of daylight or sunlight, and in response to sensing an amount of light intensity exceeding a predetermined threshold, operates via the electronics in the lower housing to turn off the night vision device 10 , thus protecting the image tube from burn-in. More particularly, photo transistor 72 B provides a signal indicative of the amount of sunlight detected at the photo transistor to a sensor circuit on printed circuit board 76 . The sensor circuit then compares the received signal with a predetermined threshold value. If the signal exceeds the threshold value, the intensifier tube is turned off, thereby protecting the image tube and extending the life of the device. An environmentally sealed purge screw 56 and o-ring 58 (FIG. 2) is located on the rear face 59 of the upper housing 50 which has a cavity (not shown) into which the screw is inserted. The purge screw permits the monocular night vision device 10 to be environmentally purged after assembly of the system is complete. This is done, for example, in order to compensate for differences in atmospheric conditions between device field operation and the manufacturing facility. As best shown in FIG. 2, the upper housing assembly optically aligns a light transmitting ring 36 between the image intensifier 20 and eyepiece lens assembly 30 for transmitting light from LEDs 78 and 79 on lower housing 70 outside the user's optical field of view. Light transmitting ring 36 in the preferred embodiment, is cylindrical in shape and made of a clear material such as acrylic to permit light from remote visible indicators (LEDs) 78 and 79 at the lower housing assembly 70 to be transmitted to the peripheral field of view of the user. Flats 36 A and 36 B on the outside diameter of the light transmitting ring accept light from respective LEDs 78 , 79 and transmit the light to flats 36 C and 36 D respectively on the inside diameter. The transmitted light is thereby transmitted along the optical path and thus appears in the user's field of view, thereby providing a signal to the user. The ring is positioned as illustrated in FIG. 2 and oriented with respect to the lower housing assembly 70 such that flats 36 A and 36 B are vertically aligned with respective LED indicators 78 and 79 . In this manner, the LED indicators might be housed within the compact lower housing assembly and out of the direct field of view of the user, while still permitting the light emitted from the respective indicators to be received and viewed at the eyepiece. An alignment tab on the light transmitting ring ensures proper alignment with the upper housing. Referring to FIG. 5A, the lower housing assembly, as previously discussed, includes a rigid printed circuit board (PCB) assembly 76 fastened directly thereto. Several interfacing electrical components are located on the upper side of the rigid PCB. A plastic housing or carrier 74 is located on the PCB which holds conventional IRLED 72 A and photo transistor 72 B. Also on the rigid PCB are conventional tube contacts 82 as used in the AN/AVS-6 tube which provide electrical connection to the image intensifier. Two LEDs 78 , 79 on the PCB provide indication of low battery power and activation of the IRLED, respectively. A low battery sensor circuit 108 of the conventional type is included within the electronics on lower housing 70 for periodically measuring the power output from the batteries and comparing the measured power with a predetermined threshold. When the measured battery power drops below the predetermined threshold, the battery sensor circuit is operable to activate LED 78 to provide a signal indicative of the low battery condition. The signal is transmitted into the user's field of view via the lighttransmitting ring 36 from low battery power LED 78 . Note also that the PCB incorporates a four socket connector 75 for tube variable gain which aligns with and accepts the four pin connector from the image intensifier, as will be further discussed. Lower housing 70 further comprises a battery cavity 80 designed to hold batteries and oriented in-line with the optical axis. The opening for the battery cavity is integral with the front face 85 and provides a monocular night vision device that is comfortable to hold in the hand. Preferably the battery cavity holds two AA batteries. Use of two AA batteries provides both a worldwide common battery, as well as extending battery life under severe cold conditions. The lower housing 70 further contains a flex circuit assembly 87 consisting of a flexible pcb which provides for electrical contact between system components. This flex circuit assembly 87 electrically connects standard rotary switch 91 as employed in the AN/PVS-7 system with the battery power supply. This switch provides the following controls: OFF/SYSTEM ON/MOMENTARY IR ON/LOCKED IR ON. The SYSTEM ON mode is reached by turning clockwise from the OFF position. When the switch is positioned to SYSTEM ON mode, the tube is operational; however, the IR capability is non-functional in this mode. The switch is spring loaded such that turning of the switch knob 91 in the clockwise direction for SYSTEM ON mode activates the MOMENTARY IR ON mode to permit IR signaling. In this manner, one may use the MOMENTARY IR ON mode to send Morse Code or other such signaling in a covert manner. Locked IR ON mode provides continuous IR feature and is enabled by pulling the switch knob towards the user and turning in a clockwise manner to allow engagement of this mode. Note that the switch is electrically coupled to potentiometer 27 (FIG. 3) for adjustment of the image intensifier's gain level. Two female pin connectors are also part of the flex circuit assembly. These connectors are attached to the two contacts 82 in the upper housing assembly when the upper and lower housings are assembled. FIG. 13 provides a circuit schematic of the electronics in the lower housing including the PCB and contact points/terminals. FIG. 4A further shows a mounting socket 51 on the outer surface 53 of upper housing assembly 50 for mounting to an apparatus such as a head/helmet mount adapter or small arms mounting adapter. Preferably, mounting socket 51 is a ¼″ threaded insert. Proximal to the mounting socket, and preferably directly below, on surface 53 , is a triangular alignment feature 55 which aids in both aligning and orienting the head/helmet mount adapter or small arms mounting adapter. Two contacts 58 positioned adjacent to the mounting socket provide electrical contact between the monocular night vision device 10 and the head/helmet mount adapter. FIGS. 8A-B illustrate a head/helmet mount adapter 200 for coupling to the monocular night vision device 10 . This adapter allows the monocular night vision device to be mounted to a standard AN/PVS-7 head mount or helmet mount. An adjustable mounting arm 210 , which can be rotated 180 degrees (see FIG. 9) allows the monocular night vision device to be positioned in front of either the left or right eye as shown in FIG. 10 . This adapter incorporates a mounting horn 220 and mounting latch 228 . A magnetic reed switch 230 positioned beneath mounting horn 220 operates to turn off the monocular night vision device when removed from the headmount or helmet mount or when flipped-up in the helmet mount. A cable assembly runs from the reed switch 230 down the mounting arm 210 and to a set of contacts 232 at the opposite end of the mounting arm. These two contacts align with the contacts 58 on the upper monocular housing surface 53 when the adapter is fastened to the monocular's upper housing. Preferably, a captivated 0.25″ thumbscrew allows for fastening the adapter 200 to the monocular night vision device at mounting socket 51 . The triangular alignment feature 250 located near the thumbscrew aids in orienting the monocular night vision device to the adapter. FIGS. 11 and 12 show a small arms mounting adapter 300 , incorporated as part of the monocular night vision device 10 . This adapter allows for mounting to an M16/M4 receiver rail 340 as configured for the Modular Weapon System Kit and as defined in MIL-STD-1913. The adapter positions the monocular night vision device optimally on the weapon so that the user does not have to change their normal shooting position. The adapter incorporates a torque limiting mechanism in the fastening knob assembly 310 that fastens the adapter to the mounting . rail while preventing a user from over-tightening the fastening knob assembly. Preferably, a captivated 0.25″ thumbscrew 320 allows for fastening the adapter to the monocular night vision device at mounting socket 51 . Triangular alignment feature 330 located proximal the thumbscrew 320 aids in orienting the monocular night vision device to the adapter and also helps to keep the monocular night vision device properly oriented during weapon firing. FIGS. 13A-B illustrate overall assembled and exploded views respectively, of the electronic circuit 1 comprising the rigid printed circuit board (pcb) 76 and flexible pcb circuit 87 embodied in a night vision device according to the present invention. Referring to FIG. 13B, rigid pcb 76 supports most of the device components. Connections to the main on/off/ir switch 91 , the variable gain control 99 , and sockets 10 which mate to external contacts for the magnetic reed switch (not shown) are part of the flexible pcb 87 . In addition, the flexible pcb 87 has an arm portion ending in a T-shaped segment 6 which makes the connections to spring contacts 104 , 106 at points 104 A and 106 A of the batteries as shown in FIG. 7 . This arm portion operates to eliminate the need to hand-install separate wires to the battery contacts as in done in prior art devices, including the AN/PVS-7. Other major components which are mounted on the rigid pcb include infrared illuminator diode 72 A, light sensor 72 B, left and right spring contacts 7 and 8 which help provide + and − electrical power to the intensifier tube, infrared indicator LED 78 , and a low battery indicator LED 79 . Such parts had been installed on flexible arms in prior art devices, thereby requiring more hand assembly work. The infrared illuminator diode 72 A and the light sensor 72 B are installed in a carrier 74 made of a resilient material such as plastic which snaps to the rigid PCB. The carrier 74 supports the infrared illuminator diode 72 A and light sensor 72 B, and holds the diode and sensor in the proper positions to align with windows 52 in the upper housing 50 . Referring now to FIGS. 13A-B in conjunction with FIG. 10, this rigid and flexible pcb assembly integrates all of the control electronics, except for the mounting arm wiring, together in the lower housing assembly 70 of the monocular 10 . Only the sockets 10 mate to the external contacts installed in the upper housing 50 . The sockets 10 push onto pins which are part of the external contacts. The sockets connect to the rest of the circuit in the lower housing via two flexible arms 32 of the flexible pcb 87 , thus, facilitating easy connection or disconnection with the upper housing during assembly or maintenance. Moreover, by mounting the infrared illuminator diode 72 A and the light sensor 72 B to a carrier on the rigid pcb 76 , these components do not require attachment to upper housing 50 , even though they illuminate and sense the outside world through the upper housing. The windows 52 (FIG. 4B) in the upper housing provide environmental protection to these parts, while providing optical access to the outside. The main body of the image intensifier tube is likewise mounted in the upper housing, but the spring contacts 7 and 8 bear on the side of the tube and feed power to the tube in the completed assembly. FIGS. 14A-B show top and bottom views respectively of the rigid pcb 76 , depicting the positional layout of the components on the board. Most of the circuit components are surface-mount soldered to the bottom side of the rigid pcb. The top side of the rigid pcb serves mainly to support the electro-optical components and to provide connections to the other parts of the circuit. As shown in FIG. 14A, element D 6 is the infrared illuminator LED (reference numeral 72 A in FIG. 13 ). Q 2 represents the light sensor (reference numeral 72 B in FIG. 13 ). CT 3 and CT 4 represent the spring contacts (reference numerals 7 and 8 respectively, in FIG. 13 ). TP 1 is not a separate component, but is a test point formed of a plated area 49 on the pcb, which can be momentarily connected to battery negative to reduce the high light cutoff time delay which is typically 70 seconds. This feature reduces test costs by accelerating the testing. [how is testing accelerated? Is this feature new?] A potentiometer board 27 depicted in FIG. 3 associated with the variable gain image intensifier tube plugs into the rigid pcb at sockets S 1 through S 4 . These sockets are arranged such that the distance d1 between S 3 and S 4 is less than the distance d2 between S 1 and S 2 , where S 3 -S 4 are in substantially parallel planar alignment as are S 1 -S 2 . This serves to prevent backwards installation, so that the flexible arm of the tube is always oriented the same way, and so that maintainers are not confused by the possibility of two configurations. The sockets S 1 -S 4 provide mechanical support to the potentiometer board, and this mechanical arrangement of parts enables interchangeability of tubes without the need for the maintainer to readjust any gain limits resistor. The operation of the other components on the pcb are explained below. FIG. 15 shows a pictorial isometric view of the flexible pcb 87 , which forms all the interconnections which were not accomplished on the rigid pcb. This figure shows the flexible pcb as fabricated, prior to its being folded inside the monocular. The flexible pcb is soldered to the top of the rigid pcb 76 via eight pins, as represented by reference numeral 88 . Alternatively, the flexible pcb could be permanently bonded to the rigid pcb, but the solder attachment method results in lower assembly costs. As previously described, t-shaped segment 6 provides the circuit connections to the battery, while flexible arms 32 include sockets 10 which mate to the external contacts rather than in the upper housing. Circuit connections 33 provide electrical communication between the user adjustable control knobs, variable gain element 99 (FIG. 15 B), and the rigid pcb. FIG. 16 schematically shows the overall circuit for the variable-gain night-vision monocular. Note that the values associated with the components identified in FIGS. 16 and 17 are exemplary, and that other values may be utilized in combination to achieve similar results. The electrical interconnections on the flexible pcb which connect the rigid pcb and batteries BT 1 and BT 2 with the other items comprise etched copper traces bonded to the flexible support material, which preferably is polyamide. Note that the variable gain image intensifier assembly is described in detail in patent application Ser. No. 09/123,371, and incorporated herein by reference. The image intensifier tube connects to the rigid pcb via the tube spring contacts 7 and 8 and via the sockets S 1 through S 4 through potentiometer board 27 . The terminals high and low are electrically connected between the image intensifier tube 20 and potentiometer board 27 via the flexible circuit. As shown in FIG. 16, the potentiometer labeled 170 is used to factory set the minimum gain limit of the tube. The minimum gain limit is set by connecting a short circuit between the S 3 -S 2 pin pair and the S 1 -S 4 pin pair and then adjusting potentiometer 170 to establish the desired minimum gain. The short circuit represents the minimum resistance of the external circuit in the night vision device, and the user's gain adjustment control 290 is adjusted to a minimum. The maximum gain limit is set by connecting a resistor of a defined fixed value between the S 1 -S 4 pin pair and S 2 -S 3 pin pair and adjusting the potentiometer 160 to establish the maximum gain. The fixed resistance represents the maximum resistance of the external circuit in the night vision system when the user's gain adjustment control is adjusted to maximum. The potentiometer board also contains the fixed resistor 180 which is connected in series with potentiometer 160 to establish the desired adjustment range, allowing full use of the available adjustment range of potentiometer 160 for ease of gain setting, while returning enough adjustment range to allow a number of combinations of power supplies and tube modules to be set up to the same gain limit. Preferably, the potentiometer 160 is a 500 KΩ potentiometer, potentiometer 170 is a 200 KΩ potentiometer and resistor 180 is 182 KΩ In this range, there is some interaction between the settings of potentiometers 160 and 170 . Note that the four sockets S 1 -S 4 which are used to receive the potentiometer board provide improved mechanical support and improve the electrical reliability, such that any one connection can be open without affecting the operation of the circuit. Note further that, as previously described, pin S 4 is offset to prevent the board from being plugged backwards into the system. Thus, as one can ascertain, potentiometers 160 and 170 on the potentiometer board 27 set the maximum and minimum gain achievable by a user through adjustment of potentiometer 290 by using the external gain control knob 99 (see FIG. 1, 13 ). The user's gain adjustment control R 13 is a potentiometer connected to the flexible pcb. The user's gain adjustment control also includes a tab 192 attached to the housing of the potentiometer 290 , which is electrically connected to the shaft of the potentiometer. This tab is connected through the flexible pcb to battery negative B−, which is circuit “ground”. This connection protects the variable gain tube assembly from potentially damaging electrostatic discharges (esd) by diverting esd currents to “ground” and away from the sensitive gain control components in the tube's integral power supply. The onl/offer switch 91 is a three-position switch like that used in the AN/PVS-7. The on/off/ir switch is connected to the battery and to the rigid pcb via connections on the flexible pcb 87 . The head/helmet mount adapter assembly 200 , as shown schematically in FIG. 16, is detachable from the monocular. The head/helmet mount adapter assembly or mounting arm contains the magnetic reed switch 230 which senses the flipped up or detached state of the adapter with respect to the head mount or helmet mount. The head/helmet mount adapter assembly also contains an interconnecting cable 68 and two spring contacts 69 A,B which mate to the respective fixed contacts CT 1 and CT 2 which are part of the upper housing of the monocular. Unlike the AN/PVS-7, only two of the magnetic reed switch connections are used in the monocular. When reed switch 230 is in the de-energized position (i.e. position A), no electrical contact is made between head/helmet mount assembly and the printed circuit board 76 . When the reed switch senses the connectivity between the spring contacts mating to the fixed contacts CT 1 and CT 2 (reference numerals 58 ) on the upper housing, the reed switch activates to position B. The circuit is completed to the rigid pcb via sockets S 5 and S 6 , and by the arms 32 of the flexible pcb 87 to contact points labeled as MRS and MRS_RTN for signaling to ASIC 500 (FIG. 17 ). This circuit is open unless the head/helmet mount adapter assembly is attached to the monocular and is installed in the flipped-down position in the head or helmet mount, in which case the magnetic reed switch is in proximity to the magnet in the head or helmet mount and the circuit is closed (position B). The monocular housing is made of a filled polymer which is partially conductive. The filler imparts good strength to the material, as well as conductivity. The fixed contact, CT 1 , is mounted in an insulating cup (not shown) installed in the housing wall, so that this contact is electrically isolated. The other fixed contact, CT 2 , is mounted directly in the housing wall, as this side of the circuit eventually returns to circuit ground and does not need to be isolated from the housing. Both contacts, CT 1 and CT 2 , are recessed in the upper housing wall to provide additional mechanical protection and to prevent short circuiting when the monocular is mounted to the small arms adapter or when touching other conductive surfaces. The insulating cup associated with the contact CT 1 comprises a thin material which permits esd to arc from CT 1 to the partially conductive housing, thereby safely dissipating much of the esd energy before it can damage internal components. FIG. 17 schematically shows the portion of the circuit contained on the rigid pcb 76 . Connections to the flexible circuit 87 are labeled with names corresponding to the names shown on the rigid pcb schematic in FIG. 16 . While much of the circuit is the same as that used and described in the AN/PVS-7 system, the differences include the circuit portions associated with the magnetic reed switch interface circuit and the variable gain interface circuit. Note that ASIC 500 is of a type used in prior art night vision devices, such as in the AN/PVS-7, and used as part of the circuit functionality, and that resistance values are in ohms while capacitance values are indicated in microfarads (μF). The ASIC input, pin 4 , (MRS) senses the state of the magnetic reed switch, as described above. This input is a CMOS input and is subject to damage from electrostatic discharge or esd. In addition, the magnetic reed switch 230 can “bounce” when it is changing state, causing spurious edges on the input signal, which would cause the image intensifier to turn off at times when this function is unintended. The components between MRS input to the circuit 510 and the MRS input to the ASIC (pin 4 ) form a protective/filtering network, which prevents damage from esd and prevents unintentional turn-off. The MRS and MRS_RTN inputs ( 510 , 520 ) to the rigid pcb have series resistors, R 4 and R 14 , respectively, which help absorb any esd energy and help isolate the exposed contacts and the external reed switch circuit from the circuits internal to the housing. R 4 and R 14 are surface-mount resistors which are physically larger [how large? What requirements?] than the size typically used in the remainder of the circuit in order to absorb the esd without incurring physical damage. Alternatively, other types of larger leaded resistors may also be used. However, the use of surface-mount resistors include the advantages of low cost and ease of installation along with the other surface-mount parts in a compatible process. Inductors L 1 and L 2 are connected in series with R 4 and R 14 respectively. These components, along with capacitor C 8 , connected between L 1 and L 2 and to local ground 530 , form a filter network 540 to reduce the speed of the esd waveform and to further reduce peak voltage(s) of the esd waveform. Series resistor R 15 and shunt capacitor C 10 form an additional filter network 550 . Resistor R 11 connects to the positive supply voltage B+ (600) for the ASIC, and serves to pull the MRS input 4 of the ASIC to a logic “high” state when the head/helmet mount adapter assembly is disconnected, or when the head/helmet mount adapter assembly is removed or flipped up from the head mount or helmet mount, such that the magnetic reed switch is in the open state. The resistance value of resistor R 11 is chosen so that the resistor does not consume excessive current when the magnetic reed switch is closed. When the head/helmet mount adapter assembly is installed on the monocular and the adapter is in the operating position in the head or helmet mount, the magnetic reed switch is in proximity to the magnet and is in the closed state. In this state, the MRS input of the ASIC is pulled to a logic “low” state by the action of the voltage drop across R 11 , produced by the current path through R 15 , L 1 , R 4 , the external magnetic reed switch in the mounting arm, R 14 and L 2 , to local ground 530 . Resistor R 13 conducts the logic “high” or “low” signal to the MRS input 4 of the ASIC, and provides further protection from esd or other overcurrent to this input. The dual diode, D 3 , operates to clamp any voltage on the MRS input which would otherwise be more than one diode drop higher than the local power supply voltage or more than one diode drop lower than ground. In this manner, D 3 affords additional protection to the MRS input of the ASIC. Resistor R 11 and the combination of capacitor C 10 with C 8 form a filter 560 which removes any spurious edges associated with the bounce of the magnetic reed switch, before the edges can reach the MRS input of the ASIC. The capacitors, C 11 and C 7 , connected from the positive supply voltage 600 of the ASIC to local ground 530 , filter the supply voltage and help absorb additional esd transient energy. Still referring to FIG. 17 in conjunction with FIG. 16, the gain limits potentiometer board 27 , which is part of the variable gain tube assembly, interconnects with or “plugs into” the rigid pcb 76 at sockets S 1 through S 4 . S 1 and S 4 are connected electrically in common, as are S 2 and S 3 . These common connections provide redundant contacts for increased reliability of the connections from the variable gain intensifier tube 20 to the user's gain adjustment control 290 . These connections proceed through the rigid pcb to the flexible pcb and finally to the user's gain control potentiometer. While a mechanical rotary potentiometer is illustrated in the present embodiment, alternative embodiments such as electrically-alterable potentiometers are also contemplated. On the rigid pcb 76 , the series combination of the fixed resistor, R 17 , and the screwdriver-adjust trim potentiometer, R 12 , are connected in parallel with the user's gain control potentiometer. Following assembly of the circuit resistor, R 17 is adjusted once to establish a fixed resistance from the S 1 /S 4 pair to the S 2 /S 3 pair when the user's gain control is set to maximum. The fixed resistance value chosen in this embodiment is 174 kΩ, but it is understood that other values could be selected for other systems. This adjustment of resistor R 17 operates to correct for manufacturing variations in the maximum resistance of the user's gain control, so that all monoculars will produce the same maximum gain when tested with identical tubes. The user's gain adjustment control goes virtually to zero ohms when it is set to minimum. This assures that all monoculars will also produce the same minimum gain when tested with identical tubes. Since the tubes have all been adjusted to produce the same gain limits, all the tubes are interchangeable in all the monoculars of this type, producing the same maximum and minimum gain limits without the need for a maintainer to make any adjustments. The remainder of the circuit schematic operates as follows. Positive battery power, B+, is supplied from the battery via the on/off/ir switch 91 . The series resistor, R 8 , limits inrush current and protects the ASIC from overcurrent if the batteries are installed backwards. The positive battery power is fed to the ASIC via the power input (pin 14 , VDD). Resistor R 10 pulls the test input (pin 3 , TST) of the ASIC up to the positive input voltage. This is the normal operating condition, and the test input enables the full divider chain in the ASIC to produce the full highlight shutdown delay time. As described above, if the test point TP 1 is grounded, the ASIC reduces the shutdown delay time to hasten the test cycle. Resistor R 5 is a screwdriver-adjust potentiometer, used to factory-set the low battery indicator threshold as described above. R 5 can also be implemented as a series pair of trimmable resistors. The tap point of R 5 connects to the low battery sensor input (pin 1 , LBRDJ) of the ASIC. Q 2 is the photo transistor which serves as the light sensor for high-light cutoff. Its collector is pulled up to the positive supply voltage by R 1 . Alternatively, Q 2 can be a photo resistor. Upon exposure to light, Q 2 conducts current to ground, creating a voltage drop across R 1 . When the voltage goes below the threshold of the high light shutdown input (pin 13 , HLSD), the ASIC begins its time-delay sequence, culminating in shutdown of the intensifier tube if the high-light condition persists. Capacitor C 6 and resistor R 2 , connected to the oscillator (pins 12 , OSC 1 , and 11 , OCSO) of the ASIC form the timing network which replaces the crystal in FIG. 6 (prior art) and controls the oscillator frequency. Two outputs of the ASIC, pins 10 (CP 1 ), and 9 , (CP 2 ) switch between the positive supply voltage and ground at the oscillator frequency. These drive the multiplier network 570 consisting of C 2 , C 3 , C 4 , C 5 and dual diodes, D 1 and D 2 . The multiplier network steps up the positive supply voltage sufficiently to assure that the gate voltage of the power switching FET, Q 1 , will be adequate to establish a low resistance in the drain-source circuit of the FET, when on. The output voltage of the multiplier is fed to the gate of Q 1 and to the power switch control output (pin 5 , PWRSW) of the ASIC, via a series resistor, R 3 . Normally, pin 5 of the ASIC draws no current. Pin 5 draws current when the ASIC shuts down the intensifier. In this case, the voltage drop produced across R 3 lowers the gate voltage of Q 1 to a value below the threshold voltage of Q 1 , assuring that Q 1 ceases to draw current, turning off the intensifier tube and also turning off the infrared illuminator and infrared indicator LED, if on. The infrared illuminator connects from the positive battery voltage, via the ir contacts of the off/on/ir switch, to R 7 , a series current-limiting resistor, which in turn connects to the drain of Q 1 . In like manner, the infrared indicator LED connects from the positive battery voltage, via the ir contacts of the off/on/ir switch, to R 6 , a series current-limiting resistor, which in turn connects to the drain of Q 1 . The drain of Q 1 also connects to the negative voltage input of the image intensifier tube via the left-hand spring contact, CT 4 . Positive voltage to the tube is supplied via the right-hand spring contact, CT 3 . The capacitor, C 9 , filters the power to the intensifier tube and suppresses ripple produced by the intensifier tube's integral power supply. This circuit according to the present invention is operable within the AN/PVS-14 military night vision monocular, and in similar commercial night vision systems. This circuit can also be applied in other night vision systems such as monoculars, binoculars, binoculars, and weapon sights, where features such as variable gain, flip-up cutoff, low battery indication, infrared illumination, and high-light cutoff are needed. This circuit could also be applied in other hand-held, head-mounted, or battery-operated systems. It should be understood that a person skilled in the art may make many variations and modifications to embodiments utilizing functionally equivalent elements to those described herein. Any and all such variations or modifications, as well as others which may become apparent to those skilled in the art, are intended to be included within the scope of the invention as defined by the appended claims.

An electronic circuit for use in a monocular night vision device for electronically controlling a plurality of components within the device, the device having an objective lens assembly for receiving low intensity light, a variable gain image intensifier tube having a user adjustable variable gain controller external to the tube for adjusting the light intensity level of a visible output image, a single eyepiece lens assembly for viewing the output image from the image intensifier assembly; and a non-metallic housing comprising an upper housing for receiving the objective lens assembly, image intensifier assembly, and eyepiece lens assembly, and a lower housing containing a battery cavity for receiving batteries to power the device. The housing aligns the objective lens assembly with the image intensifier assembly and the eyepiece lens assembly along an optical axis wherein the upper and lower housing are coupled to one another along the optical axis. The electronic circuit comprises a rigid printed circuit board (pcb) located within the lower housing having a plurality of contacts for enabling electronic communication with components mounted thereon and with the variable gain image intensifier tube, the rigid pcb including a pair of contacts in electrical communication with the image intensifier tube for energizing the intensifier tube, and a flexible printed circuit board coupled to the rigid pcb and adaptable to the geometry of the upper and lower housings for electronically interconnecting components located within the upper and lower housings with the rigid pcb, the flexible pcb having a first circuit connection to the image intensifier tube and a second circuit connection to an adjustable potentiometer mounted external to the image intensifier tube on the rigid pcb.

BACKGROUND OF THE INVENTION The invention relates to heat pipes and more particularly to entirely passive heat pipes capable of operating against gravity. It is a result of a contract with the Department of Energy contract W-7405-ENG-36. Conventional heat pipes usually are capable of operating in a horizontal position, gravity free environment such as outer space, or with gravity assistance. A heat pipe operates with gravity assistance where heat is transported from a source located at the bottom of the pipe, its lower end, to a heat sink situated atop the pipe, at a gravitationally higher position. In such a case liquid condensed at the top of the pipe returns to the bottom thereof with the assistance of gravity. To a rather limited extent conventional heat pipes can also do the reverse, that is, transfer heat from an elevated source to a lower sink and return the condensed liquid to the top of the pipe by capillary action. It will, however, be appreciated by those skilled in the art that in practical heat pipe designs, capillary action is limited by the height to which liquids can be raised thereby, typically less than a meter. SUMMARY OF THE INVENTION It is one object of the invention to provide a passive heat pipe with an extended pumping height for transferring heat from an elevated source to a lower sink. It is another object of the invention to provide in a purely passive device pumping heights in the 3 to 7 meter (m) or greater range. In accordance with the present invention there is provided a heat pipe apparatus capable of operating against gravity comprising a heat pipe envelope containing an evaporator and a condenser, the evaporator being disposed gravitationally above the condenser. A gas and a working fluid are disposed within the envelope, the fluid comprising a liquid and its vapor. A venturi is disposed between the evaporator and the condenser and a reservoir is located in the vicinity of the venturi. The reservoir contains the fluid in its liquid phase and the gas. A conduit, such as a tube, provides a path for the liquid and the gas between the condenser and the reservoir. The conduit may be disposed entirely within the heat pipe envelope or a substantial portion of it can be external of the envelope if so desired. A capillary wick is provided between the reservoir and the evaporator for carrying the liquid in the reservoir to the evaporator. An ejector is disposed at the venturi for introducing gas from the reservoir into the venturi. The heat pipe can move heat in a 3 to 10 m range and is entirely passive. One advantage of the instant invention is that it has wide application in space and water heating using solar energy where typically heat is transferred from roof top solar collectors to in-ground or basement level thermal storage. Another advantage of the instant invention is that heat transfer in accordance therewith is entirely passive, there being no need for an external pump. Another advantage of the invention is that because no external pump is required, no additional sources of energy are needed to operate the heat pipe of the invention. Additional objects, advantages, and novel features of the invention will be set forth in part in the description which follows, and will become apparent to those skilled in the art upon examination of the following, or may be learned by practice of the invention. The objects and advantages of the invention may be realized and obtained by means of the instrumentalities and combinations particularly pointed out in the appended claims. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 shows a cross-sectional view of a preferred embodiment of the invention; FIG. 2 schematically shows the invention; FIG. 3 graphically illustrates a pressure profile in the heat pipes of FIGS. 1 and 2; FIG. 4 illustrates another embodiment of the invention; and FIG. 5 depicts yet another embodiment of the invention. DETAILED DESCRIPTION OF THE INVENTION Reference is now made to FIG. 1 which illustrates a preferred embodiment of the invention. Because heat pipes in accordance with the invention in typical applications will be quite long, on the order of 3 to 10 meters, and are only perhaps 2 to 10 centimeters (cm) in diameter, the illustration in FIG. 1 shows a severed heat pipe in order to clearly show all necessary aspects of the device in one figure. As seen in FIG. 1, a heat pipe envelope 10 comprising walls 12 and end plates 14 and 16 provides a sealed environment for a fluid comprising a liquid and its vapor. This fluid may comprise, for example, water and water vapor, freon, ammonia, or methanol. Also provided within the envelope is a gas or combination of gases such as air, nitrogen, neon, argon, or helium which does not chemically react with the fluid. The gas is, in effect, inert. The purposes of this gas will become apparent hereinafter. Heat pipe envelope 10 comprises an evaporator section or area 18 and a condenser section or area 20. As is usual in heat pipes, during operation the fluid will be in its liquid phase in the condenser section and in its vapor phase in the evaporator section. A conduit 22 is provided for liquid and gas transport from the condenser section 20 into a reservoir section 24 which contains the fluid in its liquid phase as well as gas returned through the conduit. The reservoir is disposed in the vicinity of a venturi 26 through which vapor from the evaporator section must pass. Gas from the reservoir section enters the venturi area through an ejector 28. Liquid from the reservoir 24 is carried to evaporator section 18 through a capillary wick 30 or other commonly known capillary action liquid transporting means used in heat pipes. Portion 32 of wick 30 lines the walls of the evaporator section to provide a source of vapor. Initially the gas is evenly distributed throughout the heat pipe envelope and heat is applied to the evaporator section. The heat produces vapor from the wick portion 32. This creates a pressure P 1 in the evaporator section of the heat pipe as noted in FIG. 3. FIG. 2 schematically shows the heat pipe of the invention of FIG. 1, illustrating pressures present in the FIG. 1 embodiment. As the gas and vapor pass through venturi 26, pressure therein decreases. As the flow of the vapor and gas reaches an equilibrium or steady state in the venturi, the pressure therein reaches P 2 , P 2 being always less than P 1 . As the vapor and gas enter the condenser section 20 of the heat pipe envelope 10, the vapor condenses on the walls of the condenser section and a liquid pool forms at the very bottom of the heat pipe on end plate 14. This liquid is at a pressure of P 3 , P 3 being greater than P 2 . The pressure difference, P 3 -P 2 , forces liquid which has condensed from the vapor as well as the gas which accumulates just above the pool into the conduit 22. In practice, liquid bubbles occur spaced between volumetrically larger amounts of gas such that the average density of the returning gas-liquid mixture is about 1-10% of the density of the condensed liquid. The pressure differential pushes the gas and liquid through conduit 22 up into the reservoir 24. Movement of gas and liquid up large heights is possible because the average density of the gas and liquid is much less than that for the liquid alone. As can be seen in FIG. 2, the conduit need not be entirely internal of the heat pipe envelope but may be an external element as shown in FIG. 2 as conduit 22'. The returning liquid pours over the lip of the conduit and accumulates in the reservoir. The liquid is transported therefrom through a conventional heat pipe wick 30 such as a screen or other type of capillary device up to wick 32 in the evaporator section of the heat pipe. The gas arriving in the reservoir has a pressure P 4 which is greater than P 2 but less than P 3 . The gas is reintroduced into the system through ejector 28 into the venturi. At this point a continuous process has been reached. Liquid returned to the reservoir and passed from there to the evaporator section turns into vapor. Returning gas has been reintroduced into the venturi. Once the heat pipe is operating, essentially no gas remains in the evaporator section although some residual gas there would not make any difference to the operation of the device. The primary purpose of the gas is to greatly reduce the specific density of the liquid returning from the condenser section to the evaporator section over a length of several meters. Capillary action of a wick can not return liquid the vertical distances reached in practicing the invention. Because a small fraction of the kinetic energy of the vapor is used to cause the uncondensable gas to flow up the liquid return tube, the uncondensable gas lowers the average density of the returning gas liquid mixture considerably below that of a fully liquid column. An apparatus in accordance with the invention can operate over fairly large vertical distances. Thus for a given pressure difference available for pumping, the invention provides a circulating fluid to be pumped back capable of reaching much greater heights than would be possible with a fully liquid return path through a capillary. The typical wicking height for a conventional water heat pipe is 0.4 m. If the average density in the return tube or conduit is reduced by a factor of 10 in accordance with the invention, the returning gas-water fluid could flow up to a height of 4 m. As seen in FIG. 3, the pressure difference P 1 -P 2 is developed by the acceleration of the vapor as it flows out of the evaporator into the throat of the venturi ejector. As the vapor and inert gas come to rest at the bottom of the condenser, their pressure rises from P 2 to P 3 . The liquid and inert gas flow up the return tube arriving at the reservoir pressure at P 4 . The pressure difference P 3 -P 4 is the pressure head available for pumping the fluid up the return tube. The difference P 1 -P 5 is what must be provided by the capillary force in the evaporator wick to pull the liquid from the reservoir to the surface of the evaporator. Those skilled in the art will appreciate that for proper operation of a heat pipe in accordance with the invention the following conditions must be met. P 4 >P 2 , P 1 >P 3 and P 3 >P 2 . For two-phase flow in vertical tubes calculations can be made utilizing equations shown in One Dimensional Two Phase Flow by G. B. Wallis, McGraw Hill, Inc., 1969. Appropriate pressures can be calculated using well-known established theory for venturi ejector performance such as given in Fundamentals of Gas Dynamics, by L. Crocco, Vol. III, edited by H. W. Emmons, Princeton University Press, 1958. Calculations show that a water vapor heat pipe utilizing air as the inert gas should be able to operate against gravity at heights up to several meters, such as about 7 m. Another embodiment of a heat pipe in accordance with the invention is shown in FIG. 4. Therein, a heat pipe envelope 40 which is particularly adapted for use in solar energy applications comprises an evaporator section 42 which could advantageously utilize the incline of an inclined roof. It could alternatively comprise an evaporator section in a horizontal position employable on a flat foor. Collected energy moves from the evaporator section to a condenser section 44 which could be located in a basement or at ground level. The configuration of its ejector 46 is different than in the embodiment of FIG. 1. Too, its reservoir 48 is located in a different position. A venturi 50 is provided as is a return conduit 52. However, its operation is the same as that of the device of FIG. 1. Envelope 40 is a lengthy device and a break is shown, this embodiment being about 7 or 8 m high. FIG. 5 illustrates another embodiment of the invention having a heat pipe envelope 60, a return conduit 62, a venturi 64, a reservoir 70 and an evaporator wick 72. An ejector 66 is essentially the same configuration as ejector 64 of FIG. 4. The difference between the FIG. 5 embodiment and that of FIG. 4 is that a vertical liquid reservoir including a stand pipe 68 is provided in order to raise the pressure on the liquid at the bottom of reservoir 70 utilizing the height of the liquid column above it. This reduces the pressure difference across evaporator wick 72 and thereby reduces the capillary force requirement of the wick's design. A small penalty is paid for this configuration in that the liquid in the return tube has to be raised the additional height of the stand pipe. The foregoing description of several embodiments of the invention has been presented for purposes of illustration and description and is not intended to be exhaustive or to limit the invention to the precise forms disclosed. They were chosen and described in order to best explain the principles of the invention and their practical application to thereby enable others skilled in the art to best utilize the invention in various embodiments and with various modifications as are suited to the particular use contemplated. It is intended that the scope of the invention be defined by the claims appended hereto.

The disclosure is directed to an entirely passive heat pipe apparatus capable of operating against gravity for vertical distances in the order of 3 to 7 meters and more. A return conduit into which an inert gas is introduced is used to lower the specific density of the working fluid so that it may be returned a greater vertical distance from condenser to evaporator.

CROSS REFERENCES TO RELATED APPLICATIONS [0001] The present invention contains subject matter related to Japanese Patent Applications JP 2005-376516 filed in the Japanese Patent Office on Dec. 27, 2005 and JP 2006-189365 filed in the Japanese Patent Office on Jul. 10, 2006, the entire contents of which are incorporated herein by reference. BACKGROUND OF THE INVENTION [0002] 1. Field of the Invention [0003] The present invention relates to an information processing system, a content output apparatus, and a method and program of controlling an information processing apparatus by a content output apparatus, and more particularly, to an information processing system, a content output apparatus, and a method and program of controlling an information processing apparatus by a content output apparatus, which are advantageously applicable to, for example, a system including a disk drive and a personal computer. [0004] 2. Description of the Related Art [0005] In a technique of using a disk drive as an audio data recording/playing back apparatus and also as a storage device of a personal computer or the like, it is known to control the operation mode thereof such that when the disk drive is connected to the personal computer, the disk drive is automatically set to operate as the audio data recording/playing back apparatus or as the storage device depending on whether a particular application is running on the personal computer (see, for example, Japanese Unexamined Patent Application Publication No. 2004-94815). SUMMARY OF THE INVENTION [0006] In the disk drive configured so as to operate in the above-described manner, when the disk drive is connected to the personal computer, the personal computer operates as a master device and the disk drive operates as a slave device. In this state, in general, the disk drive is treated as a simple storage device and the disk drive operating as the slave device is not allowed to control the personal computer operating as the master device. [0007] To allow the disk drive operating as the slave device to control the personal computer operating as the master device, a special driver and a complicated configuration are necessary. [0008] In view of the above, the present invention provides an information processing system, a content output apparatus, and a method and a program of controlling an information processing apparatus by a content output apparatus, configured in a simple form and capable of allowing the content output apparatus serving as a slave device to control the information processing apparatus serving as a master device to execute a particular function. [0009] According to an embodiment of the present invention, there is provided an information processing system including an information processing apparatus and a content output apparatus which are connected to each other, in which the content output apparatus includes function identification file creation means for, in accordance with a button operation by a user, creating a function identification file for causing the information processing apparatus to execute a predetermined function, and file storage means for storing the function identification file in storage means, and the information processing apparatus includes detection means for detecting a connection of the content output apparatus to the information processing apparatus, and control means for, after detecting the connection of the content output apparatus, starting an application program to execute the function depending on the presence/absence of the function identification file stored in the storage means. [0010] This configuration of the system makes it possible for the information processing apparatus to start the application program to execute the particular function specified by the function identification file simply by checking whether there is the function identification file created by the content output apparatus. [0011] According to another embodiment of the present invention, there is provided an information processing system including an information processing apparatus and a content output apparatus which are connected to each other, in which the content output apparatus includes function identification file creation means for creating a function identification file for causing the information processing apparatus to record, on a recording medium, content data stored in the content output apparatus, type identification file creation means for, if a content type of content data to be recorded on the recording medium is selected, creating a type identification file in which type information indicating the content type is described, and file storage means for storing the function identification file and the type identification file in storage means, and the information processing apparatus includes detection means for detecting a connection of the content output apparatus to the information processing apparatus, and control means for, after detecting the connection of the content output apparatus, starting an application program to record the content data on the recording medium depending on the presence/absence of the function identification file stored in the storage means, and recording on the recording medium the content data stored in the content output apparatus in accordance with the type information described in the type information file. [0012] In this information processing system, the information processing apparatus determines whether there is the function identification file created by the content output apparatus and records content data output by the content output apparatus on a recording medium of a type corresponding to the content type indicated by the type information described in the type information file. [0013] As can be seen from the above-description, the present invention provides great advantages. That is, the information processing apparatus is capable of starting the application program to execute the particular function corresponding to the function identification file simply by determining whether there is the function identification file created by the content output apparatus. Thus, the present invention allows it to realize the information processing system, the content output apparatus, and the method and the program of controlling the information processing apparatus by the content output apparatus, which are configured in a simple form so as to allow the content output apparatus to control the information processing apparatus to execute the particular function. [0014] The present invention also allows it to realize the information processing system, the content output apparatus, and the method and the program of controlling the information processing apparatus by the content output apparatus, in which the information processing apparatus determines whether there is the function identification file created by the content output apparatus, and records content data output from the content output apparatus on a recording medium of a type corresponding to the content type indicated by the type information described in the type identification file. BRIEF DESCRIPTION OF THE DRAWINGS [0015] FIG. 1 is a perspective view schematically showing a general configuration of an information processing system according to an embodiment of the present invention; [0016] FIG. 2 is a schematic block diagram showing a circuit configuration of an HDD video camera according to an embodiment of the present invention; [0017] FIG. 3 is a schematic block diagram showing a circuit configuration of a personal computer; [0018] FIG. 4 is a flow chart showing a processing sequence of writing content data supplied from an HDD video camera on a DVD disk; [0019] FIG. 5 is a schematic diagram showing a graphical user interface (GUI) screen of an HDD video camera; [0020] FIG. 6 is a schematic diagram showing a file system of an HDD video camera according to an embodiment of the present invention; [0021] FIG. 7 is a schematic diagram showing a launcher menu screen according to an embodiment of the present invention; [0022] FIG. 8 is a perspective view schematically showing a general configuration of an information processing system according to an embodiment of the present invention; [0023] FIG. 9 is a schematic block diagram showing a circuit configuration of an HDD video camera according to an embodiment of the present invention; [0024] FIG. 10 is a schematic diagram showing a various kinds contents recorded on an HDD; [0025] FIG. 11 is a flow chart showing a pre-process performed by an HDD video camera according to an embodiment of the present invention; [0026] FIG. 12 is a schematic diagram showing a content type selection screen; [0027] FIG. 13 is a flow chart showing a part of a processing sequence of writing content data supplied from an HDD video camera in an optimum manner depending on the content type according to an embodiment of the present invention; [0028] FIG. 14 is a flow chart showing a following part of the processing sequence of writing content data supplied from an HDD video camera in an optimum manner depending on the content type according to an embodiment of the present invention; [0029] FIG. 15 is a schematic diagram showing a graphical user interface (GUI) screen of an HDD video camera; [0030] FIG. 16 is a schematic diagram showing an example of content of a camera identification file; [0031] FIG. 17 is a schematic diagram showing a file system of an HDD video camera according to an embodiment of the present invention; and [0032] FIG. 18 is a schematic diagram showing a launcher menu screen according to an embodiment of the present invention. DESCRIPTION OF THE PREFERRED EMBODIMENTS [0033] The present invention is described in detail below with reference to embodiments in conjunction with the accompanying drawings. First Embodiment General Configuration of Information Processing System [0034] As shown in FIG. 1 , an information processing system 1 according to a first embodiment of the invention includes an HDD (Hard Disk Drive) video camera 2 configured to take an image and store the image in the form of a moving image file or a still image file on a built-in hard disk drive, and a personal computer 4 connected to the HDD video camera 2 via a communication interface such as a USB (Universal Serial Bus) cable 3 or the like. [0035] When the HDD video camera 2 is connected to the personal computer 4 via the USB cable 3 , the personal computer 4 operates as a master device, and the HDD video camera 2 is simply treated as a storage device. In this state, by using an application program installed on the personal computer 4 , the personal computer 4 is capable of capturing the moving image file or the still image file from the HDD video camera 2 and storing it for backup in the personal computer 4 or printing an image according to the captured moving image file or the still image file. [0036] That is, when the HDD video camera 2 and the personal computer 4 are connected to each other via the USB cable 3 , the personal computer 4 operates as the master device and the HDD video camera 2 operates the slave device, and thus, in general, the HDD video camera 2 is not allowed to directly control the personal computer 4 . [0037] However, in the information processing system 1 according to an embodiment of the present invention, the HDD video camera 2 operating as the slave device is allowed to indirectly control the personal computer 4 operating as the master device to store a moving image file or a still image file output from the HDD video camera 2 in the personal computer 4 or on a DVD disk or the like by using the personal computer 4 . [0038] In the information processing system 1 according to the present embodiment, it is assumed that the HDD video camera 2 is connected to the personal computer 4 via a communication interface using a cable such as a USB cable 3 . Alternatively, the HDD video camera 2 may be connected to the personal computer 4 via a wireless communication interface such as a Bluetooth (trademark) module or an IEEE (Institute of Electrical and Electronics Engineers) 802.11g wireless communication module. Circuit Configuration of the HDD Video Camera [0039] As shown in FIG. 2 , the HDD video camera 2 operates with electric power supplied by a battery (not shown). A CPU (Central Processing Unit) 10 loads a basic program and various kinds of application programs from a ROM (Read Only Memory) 11 into a RAM (Random Access Memory) 12 and controls the whole HDD video camera 2 in accordance with the basic program and various kinds of application programs loaded in the RAM 12 . In response to pressing of one of a set of operation buttons 13 by a user, the CPU 10 performs various processes such as capturing of an image, a playback process, an editing process, etc. depending on which one of the set of buttons is pressed. [0040] More specifically, when a particular one of the set of operation buttons 13 is pressed by a user to take an image, the CPU 10 of the HDD video camera 2 performs particular image processing, using an image processor 15 , on image data S 1 output from a CCD (Charge Coupled Device) camera 14 , and image data S 2 is obtained as a result. [0041] Concurrently, the CPU 10 of the HDD video camera 2 converts audio data S 3 detected by the microphone 17 into audio data S 4 by performing audio processing using the audio processor 18 . [0042] The CPU 10 of the HDD video camera 2 produces a moving image file DF including SD image data S 2 and associated audio data S 4 and the stores the generated moving image file DF in the hard disk drive 16 . [0043] In the HDD video camera 2 , when still image data S 5 is captured via the CCD camera 14 , the CPU 10 performs image processing on the still image data S 5 using the image processor 15 . Still image data S 6 obtained as a result of the image processing is stored as a still image file SF in the hard disk drive 16 . [0044] When a user presses a particular one of the set of buttons 13 , the CPU 10 of the HDD video camera 2 reads the moving image file DF or the still image file SF, depending on the pressed button, from the HDD 16 and displays a moving image or a still image on a LCD (Liquid Crystal Display) 19 in accordance with the moving image file DF or the still image file SF. [0045] The CPU 10 of the HDD video camera 2 is connected to the personal computer 4 via the USB interface 20 and the USB cable 3 ( FIG. 1 ) so that the moving image file DF and/or the still image file SF can be transferred from the HDD video camera 2 to the personal computer 4 and saved therein or the moving image file DF and/or the still image file SF can be recorded on a removable recording medium such as a DVD (Digital Versatile Disc) via the personal computer 4 . Note that the recording medium is not limited to the DVD disk but other types of recording media such as a CD-R (Compact Disc-Recordable) disk or a flash memory may also be used. Circuit Configuration of the Personal Computer [0046] In the personal computer 4 , as shown in FIG. 3 , the CPU 30 loads a basic program and various kinds of application programs from a ROM 31 or a hard disk drive 34 into a RAM 32 and controls the whole personal computer 4 in accordance with the basic program and the various kinds of application program loaded in the RAM 32 . For example, the CPU 30 performs various processes in response to inputting operations, performed by a user, on a keyboard 35 and displays a result on a monitor 36 connected via a bus 33 . [0047] The personal computer 4 has a DVD drive 37 and is capable of reading data from a DVD disk mounted on the DVD drive 37 and displaying the data on the monitor 36 . The personal computer 4 is also capable of capturing a moving image file DF or a still image file SF from the HDD video camera 2 connected via the USB interface 38 and the USB cable 3 ( FIG. 1 ) and writing the captured moving image file DF or still image file SF on the hard disk drive 34 or on a DVD disk mounted on the DVD drive 37 . Sequence of Processes of Writing Data on DVD Disk under Indirect Control of HDD Video Camera [0048] In the information processing system 1 , when the HDD video camera 2 is connected to the personal computer 4 via the USB cable 3 , the HDD video camera 2 serving as the slave device is allowed to indirectly control the personal computer 4 serving as the master slave to write a moving image file DF or a still image file SF captured via the HDD video camera 2 on a DVD disk mounted on the DVD drive 37 of the personal computer 4 , as described in detail below. [0049] As shown in FIG. 4 , in step SP 1 if the CPU 10 of the HDD video camera 2 determines that the HDD video camera 2 is electrically (physically) connected with the personal computer 4 via the USB cable 3 , the CPU 10 of the HDD video camera 2 displays a pop-up window PW 1 such as that shown in FIG. 5 on a LCD 19 ( FIG. 2 ). Thereafter, the processing flow proceeds to a next step SP 2 . [0050] In the present example, a text message “Camera is going to be connected to personal computer” is displayed in the pop-up window PW 1 to indicate that although the HDD video camera 2 is electrically (physically) connected to the personal computer 4 , the HDD video camera 2 is in a state in which the HDD video camera 2 is not yet logically connected to the personal computer 4 , and thus the HDD video camera 2 is not yet set to operate as a slave device of the personal computer 4 and the HDD video camera 2 is allowed to operate independently of the personal computer 4 . [0051] In the pop-up window PW 1 , a “Copy to PC” button P 1 and a “Write on DVD” button P 2 , which are operable in response to touching, are disposed in an area below the text message “Camera is going to be connected to personal computer”. A user of the HDD video camera 2 is allowed to press one of these buttons to specify whether the moving image file DF or the still image file SF captured by the HDD video camera 2 is to be simply transferred to the personal computer 4 and stored therein, or the moving image file DF or the still image file SF is to be transferred to the personal computer 4 and written on a DVD disk. [0052] In step SP 2 , the CPU 10 of the HDD video camera 2 determines whether the “Write on DVD” button P 2 in the pop-up window PW 1 has been touched by the user. If the answer to step SP 2 is affirmative, the processing flow proceeds to step SP 3 . [0053] In step SP 3 , in response to the touching of the “Write on DVD” button P 2 by the user, the CPU 10 of the HDD video camera 2 creates a function identification file “DVDBURN.IND” to be read by the personal computer 4 and stores it on the hard disk drive 16 . Thereafter, the processing flow proceeds to step SP 4 . [0054] In step SP 3 described above, the CPU 10 of the HDD video camera 2 creates the function identification file “DVDBURN.IND” and places it directly under a root directory of a file system FS 1 , that is, as shown in FIG. 6 , the function identification file “DVDBURN.IND” is placed in parallel to a folder “MP_ROOT” and a folder “DCIM”. In the specific example shown in FIG. 6 , moving image files DF and content information management files IF (index files such as “INDEX0001.ANP”, INDEX0001.ANT”, and INDEX0001.ANM”) are stored in the folder “MP_ROOT”, and still image files SF (“DSC00001.JPG”, DSC00002.JPG”, DSC00003.JPG”, etc.) are stored in the folder DCIM. [0055] In the content information management file IF, for example, information necessary to manage content data, such as a play list, thumbnail images, meta data, etc., is described. Moving image data are stored as files with an extension of ”.MPG” (such as “M2U00001.MPG”, “M2U00002.MPG”, “M2U00003.MPG” , etc.) in a folder “100PNV01” located in the folder “MP_ROOT”. [0056] Because the function identification file “DVDBURN.IND” is placed directly under the root directory of the file system FS 1 of the HDD video camera 2 , the CPU 30 of the personal computer 4 can directly access the function identification file “DVDBURN.IND” from the root directory of the file system FS 1 without having to go into a deep hierarchical level. This allows it to easily and quickly determine whether or not the function identification file “DVDBURN.IND” exists. [0057] On the other hand, when the answer to step SP 2 is negative, that is, when the “Write on DVD” button P 2 is not touched by the user, the processing flow proceeds to step SP 4 without producing the function identification file “DVDBURN.IND”. [0058] In step SP 4 , the CPU 10 of the HDD video camera 2 logically connects the HDD video camera 2 to the personal computer 4 such that the personal computer 4 serves as a master device and the HDD video camera 2 serves as a slave device. The processing flow then proceeds to step SP 5 . [0059] If the CPU 30 of the personal computer 4 detects in step SP 5 that the HDD video camera 2 is logically connected to the personal computer 4 , then the processing flow proceeds to step SP 6 . [0060] In step SP 6 , the CPU 30 of the personal computer 4 mounts a file system FS 1 of the HDD video camera 2 from the HDD video camera 2 connected to the personal computer 4 via the USB cable 3 . The processing flow then proceeds to step SP 7 . [0061] In step SP 7 , the CPU 30 of the personal computer 4 checks the file system FS 1 of the HDD video camera 2 to determine whether the file system FS 1 includes the function identification file “DVDBURN.IND”. If the answer to step SP 7 is affirmative, the processing flow proceeds to step SP 8 . [0062] In step SP 8 , because the CPU 30 of the personal computer 4 has detected in the previous step that the file system FS 1 of the HDD video camera 2 includes the function identification file “DVDBURN.IND”, the CPU 30 of the personal computer 4 automatically starts a DVD writing program stored on the hard disk drive 34 in accordance with an information processing apparatus control program resident in a RAM 22 . The processing flow then proceeds to step SP 9 . [0063] In step SP 9 , the CPU 30 of the personal computer 4 requests the HDD video camera 2 to transfer the moving image file DF or the still image file SF according to the DVD writing program. In response to the request, the HDD video camera 2 transmits the moving image file DF or the still image file SF to the personal computer 4 . In the personal computer 4 , the received moving image file DF or the still image file SF is recorded on a DVD disk using the DVD drive 37 . Thereafter, the processing flow proceeds to step SP 12 . [0064] In step SP 12 , because the DVD writing process corresponding to the “Write on DVD” button P 2 has been completed, the CPU 10 of the HDD video camera 2 and the CPU 30 of the personal computer 4 release the logical connection between the HDD video camera 2 and the personal computer 4 . As a result, the state is released in which the personal computer 4 operates as the master device and the HDD video camera 2 serves as the slave device. The CPU 30 of the personal computer 4 advances the process to step SP 13 , while the CPU 10 of the HDD video camera 2 advances the process to step SP 14 . [0065] In step SP 14 , because the logical connection with the personal computer 4 has been released and thus the master-slave relationship has been released in the previous step, the CPU 10 of the HDD video camera 2 deletes the function identification file “DVDBURN.IND” from the file system FS 1 . The processing flow proceeds to step SP 15 . In step SP 15 , the whole process is ended. Note that steps SP 12 and SP 14 do not necessarily be executed, but these steps may be executed as required. [0066] In a case in which the answer to step SP 7 is negative, that is, in a case in which the file system FS 1 of the HDD video camera 2 does not include the function identification file “DVDBURN.IND”, it is not necessary to start the DVD writing program, and thus the CPU 30 of the personal computer 4 advances the process to step SP 10 . [0067] In step SP 10 , because the file system FS 1 of HDD video camera 2 does not include the function identification file “DVDBURN.IND”, the CPU 30 of the personal computer 4 automatically starts a default launcher application program according to the information processing apparatus control program. The processing flow then proceeds to step SP 1 . [0068] In step SP 11 , according to the launcher application program, the CPU 30 of the personal computer 4 displays a launcher menu screen LMG 1 such as that shown in FIG. 7 on the monitor 36 . [0069] On the launcher menu screen LMG 1 , there are provided a “One-Touch DVD Writing” button P 11 , a “Differential PC Backup” button P 12 , a “View Image” button P 13 , a “DVD Authoring” button P 14 , a “Play List” button P 15 , a “Settings” button P 16 , and a “Close” button P 17 . [0070] If the “One-Touch DVD Writing” button P 11 is pressed by a user, the CPU 30 of the personal computer 4 automatically starts the DVD writing program to write a moving image file DF or a still image file SF supplied from the HDD video camera 2 on a DVD disk via the DVD drive 37 . That is, when the “One-Touch DVD Writing” button P 11 is pressed, a process is performed in a similar manner to the process performed in response to pressing of the “Write on DVD” button P 2 provided in the pop-up window PW 1 of the HDD video camera 2 . [0071] In this process, the CPU 30 of the personal computer 4 determines whether there is a moving image file DF or a still image file SF supplied from the HDD video camera which is not yet recorded on the DVD disk, and records detected unrecorded moving image file DF or still image file SF on the DVD disk. In a case in which no new moving image file DF or a still image file SF to be recorded is found, an error message is displayed to inform the user of that there is no file to be recorded. [0072] When the “Differential PC Backup” button P 12 is pressed, if the HDD video camera 2 has a moving image file DF or still image file SF which has not been captured by the personal computer 4 , only such an image file is stored on the hard disk drive 34 of the personal computer 4 . When there is no difference between the image files stored in the HDD video camera 2 and the image files stored in the personal computer 4 , an error message is displayed to inform a user of this fact. [0073] The “View Image” button P 13 is used to display a specified moving or still image using a particular browser. More specifically, when the “View Image” button P 13 is pressed, the CPU 30 of the personal computer 4 displays an image according to a moving image file DF or a still image file SF captured via the HDD video camera 2 or according to a video file downloaded from a site on the Internet. [0074] When the “DVD Authoring” button P 14 is pressed by a user, the user is allowed to edit a moving image file DF or a still image file SF to be recorded on a DVD disk using the DVD writing program. More specifically, for example, the user is allowed to select parts, which are to be recorded, from the moving image file DF or the still image file SF. That is, this button allows the user to write, on a DVD disk, the moving image file DF or the still image file SF stored in the HDD video camera 2 not directly but after editing the image file. [0075] The “Play List” button P 15 is used to record moving image files DF and/or still image files SF in the order specified by a play list stored in the HDD video camera 2 . When the HDD video camera 2 has a play list, still image files SF compressed according to the JPEG standard are converted into a form according to the MPEG2 standard and the resultant image files are recorded in the same manner as the manner in which moving image files DF are recorded. However, when the HDD video camera 2 has no play list, still image files SF according to the JPEG standard are directly recorded without being converted. [0076] That is, in this mode in which moving images file DF and still image files SF are recorded in accordance with the play list, the CPU 30 of the personal computer 4 converts the JPEG still image files SF according to the same MPEG2 format as that for the moving image files DF, and thus the still image files SF recorded on the DVD disk can be played back using a DVD player capable of handling only MPEG2 files. [0077] The “Settings” button P 16 allows a user to change detailed settings associated with conditions under which to record the moving image file DF or the still image file SF on a DVD disk. The “Close” button P 17 is used to close the launcher menu screen LMG 1 . Operation and Advantages of the First Embodiment [0078] In the information processing system 1 configured in the above-described manner according to the first embodiment, when the “Write on DVD” button P 2 in the pop-up window PW 1 displayed on the LCD 19 of the HDD video camera 2 is touched by a user, the function indemnification file “DVDBURN.IND” is created and stored on the hard disk drive 16 . When the HDD video camera 2 is logically connected to the personal computer 4 , if the personal computer 4 detects this function identification file “DVDBURN.IND” of the HDD video camera 2 , the personal computer 4 automatically starts the DVD writing program in accordance with the information processing apparatus control program, reads the moving image file DF and/or the still image file SF stored in the HDD video camera 2 , and writes the moving image file DF and/or the still image file SF on a DVD disk. [0079] Thus, in the state in which the HDD video camera 2 is logically connected to the personal computer 4 such that the HDD video camera 2 operates as a slave device and the personal computer 4 operates as a master device and thus the HDD video camera 2 operating as the slave device is not allowed to directly issue a write-on-DVD command to the personal computer 4 , use of the function identification file “DVDBURN.IND” makes it possible for the HDD video camera 2 to indirectly control the personal computer 4 to record content data on a DVD disk. That is, the same effect as that achieved by directly issuing the write-on-DVD command to the personal computer 4 can be achieved indirectly. [0080] Thus, the user of the HDD video camera 2 is allowed to transfer the moving image file DF and/or the still image file SF to the personal computer 4 and write them on a DVD disk simply by touching the “Write on DVD” button P 2 without having to operate the personal computer 4 or install a special driver software program on the personal computer 4 . [0081] When the function identification file “DVDBURN.IND” is not found in the file system FS 1 of the HDD video camera 2 , the CPU 30 of the personal computer 4 displays the launcher menu screen LMG 1 on the monitor 36 . This provides an effect equivalent to that of supplying a command to display the launcher menu screen LMG 1 from the HDD video camera 2 to the personal computer 4 . [0082] When the “One-Touch DVD Writing” button P 11 on the launcher menu screen LMG 1 is pressed, the CPU 30 of the personal computer 4 also reads the moving image file DF and/or the still image file SF from the HDD video camera 2 and records them on a DVD disk. That is, in the information processing system 1 , it is allowed to write image files on a DVD disk by operating either the video camera 2 or the personal computer 4 , and thus a great improvement in usability can be achieved. [0083] In the information processing system 1 , as described above, even in the state in which the personal computer 4 is set to serve as a master device and the HDD video camera 2 is set to serve as a slave device after they have been connected to each other. it is allowed to transfer a moving image file DF and/or a still image file SF from the HDD video camera 2 to the personal computer 4 and write them on a DVD disk simply by touching a button on the HDD video camera 2 . Second Embodiment General Configuration of Information Processing System [0084] In FIG. 8 , similar parts to those in FIG. 1 are denoted by similar reference numerals. As shown in FIG. 8 , an information processing system 101 according to a second embodiment of the present invention includes an HDD video camera 102 capable of taking a moving image according to the SD (Standard Definition) or HD (High Definition) standard, and a personal computer 4 connected to the HDD video camera 102 via a communication interface such as a USB cable 3 . [0085] When the SD recording mode is selected, the HDD video camera 102 is capable of creating a moving image file according to the SD standard (hereinafter, simply referred to as an SD moving image file) and storing the created SD moving image file in a hard disk drive disposed in the HDD video camera 102 . On the other hand, in the HD recording mode, the HDD video camera 102 is capable of storing a moving image file according to the HD standard (hereinafter referred to simply as an HD moving image file) in the hard disk drive disposed in the HDD video camera 102 . [0086] When the HDD video camera 102 is connected to the personal computer 4 via the USB cable 3 , the personal computer 4 sets itself to serve as a master device and treats the HDD video camera 102 as a simple storage device. According to an application program installed on the personal computer 4 , the personal computer 4 is capable of reading an SD moving image file or an HD moving image file from the HDD video camera 102 and saving the read image file in the personal computer 4 . The personal computer 4 is also capable of printing an image according to the SD moving image file or the HD moving image file stored in the HDD video camera 102 . [0087] That is, in the state in which the HDD video camera 102 is connected to the personal computer 4 via the USB cable 3 , the personal computer 4 serves as the master device and the HDD video camera 102 serves as the slave device, and the HDD video camera 102 is not allowed to directly control the personal computer 4 . [0088] However, in the information processing system 101 according to the present embodiment of the invention, the HDD video camera 102 serving as the slave device creates a function identification file “OTDISCBN.IND” similar to the function identification file “DVDBURN.IND”, which makes it possible for the HDD video camera 102 to indirectly control the personal computer 4 via the function identification file “DVDBURN.IND” such that the personal computer 4 operates according to the function identification file “DVDBURN.IND”. [0089] Furthermore, in the information processing system 101 , when the SD moving image file or the HD moving image file read from the HDD video camera 102 serving as the slave device is stored on a recording medium by the personal computer 4 , a user is allowed to specify, by touching one of one-touch operation buttons, whether the SD moving image file or the HD moving image file is to be stored or both the SD moving image file and the HD moving image file are to be stored. [0090] In response to the selection made by the user, the HDD video camera 102 generates a camera identification file “MODELCFG.IND” in which the type of content to be recorded is described, that is, information is described to indicate whether the file specified to be recorded is the SD moving image file or the HD moving image file or both the SD moving image file and the HD moving image file are specified to be recorded. This camera identification file “MODELCFG.IND” is read by the personal computer 4 and the personal computer 4 performs a recording operation according to the camera identification file “MODELCFG.IND”. [0091] More specifically, in a case in which the CPU 30 of the personal computer 4 detects that the type information described in the camera identification file “MODELCFG.IND” stored in the HDD video camera 102 indicates that the HD moving image file type has been specified as the type of a file to be recorded, the CPU 30 of the personal computer 4 extracts only HD moving image files from the HDD video camera 102 and records the extracted HD moving image files on a Blu-ray disk in a recordable format. [0092] On the other hand, when the CPU 30 of the personal computer 4 detects that the type information described in the camera identification file “MODELCFG.IND” stored in the HDD video camera 102 indicates that the SD moving image file type has been specified as the type of a file to be recorded, the CPU 30 of the personal computer 4 extracts only SD moving image files from the HDD video camera 102 and records the extracted HD moving image files on a DVD disk in a format suitable for recording the SD moving image files. [0093] In a case in which the CPU 30 of the personal computer 4 detects that the type information described in the camera identification file “MODELCFG.IND” stored in the HDD video camera 102 indicates that both the HD moving image file and the SD moving image file are specified to be recorded, the CPU 30 of the personal computer 4 first extracts HD moving image files from the HDD video camera 102 and records them on a Blu-ray disk and then extracts SD moving image files from the HDD video camera 102 and records them on a DVD disk which is mounted after the Blu-ray disk is removed. [0094] Note that the HDD video camera 102 serving as the slave device may record a SD moving image file or a JPEG (Joint Photographic Experts Group) still image on either a DVD disk or a Blu-ray disk as required. [0095] In the information processing apparatus 101 , as described above, the HDD video camera 102 is connected to the personal computer 4 via a cable communication interface such as the USB cable 3 . However, the connection does not necessarily need to be realized using a cable but the connection may be realized using a wireless communication interface such as a Bluetooh module (trademark) or IEEE802.11g wireless communication interface. Circuit Configuration of the HDD Video Camera [0096] In FIG. 9 , similar parts to those in FIG. 2 are denoted by similar reference numerals. As shown in FIG. 9 , the HDD video camera 102 is similar in circuit configuration to the above-described HDD video camera 2 according to the first embodiment. The HDD video camera 102 operates with electric power supplied by a battery (not shown). The CPU 10 loads a basic program and various kinds of application programs from a ROM 11 into a RAM 12 and controls the whole HDD video camera 102 in accordance with the basic program and various kinds of application programs loaded in the RAM 12 . In response to pressing of one of a set of operation buttons 13 by a user, the CPU 10 performs various processes such as capturing of an image, a playback process, an editing process, etc. depending on which one of the set of buttons is pressed. [0097] More specifically, for example, when an image of a subject specified by a user is taken, in response to pressing of particular one of the set of buttons 13 , under the control of the CPU 10 of the HDD video camera 102 , it is allowed to select either the SD recording mode or the HD recording mode. Image data S 1 taken by the CCD camera 14 in the SD recording mode or image data S 11 in the HD recording mode is subjected to image processing performed by the image processor 15 . As a result, SD image data S 2 or HD image data S 12 is obtained. [0098] Concurrently, the CPU 10 of the HDD video camera 102 converts audio data S 3 detected by the microphone 17 into audio data S 4 by performing audio processing using the audio processor 18 . [0099] When the operation in the SD recording mode, the CPU 10 of the HDD video camera 102 produces an SD moving image file SDF including SD image data S 2 and associated audio data S 4 and stores the resultant SD moving image file SDF in the hard disk drive 16 . On the other hand, when the operation is in the HD recording mode, the CPU 10 of the HDD video camera 102 produces an HD moving image file HDF including HD image data S 12 and associated audio data S 4 and stores the resultant HD moving image file HDF in the hard disk drive 16 . [0100] Thus, in the HDD video camera 102 , as shown in FIG. 10 , a mixture of HD moving image files HDF and SD moving image files SDF is stored on a hard disk by the hard disk drive 16 . [0101] When still image data S 5 is captured by the CCD camera 14 , the CPU 10 of the HDD video camera 102 converts the still image data S 5 into still image data S 6 by performing image processing using the image processor 15 and stores the result as a still image file SF in the hard disk drive 16 . [0102] When a user presses a particular one of the set of operation buttons 13 to select a particular SD moving file SDF, an HD moving image file HDF, or a still image file SF, the CPU 10 of the HDD video camera 102 reads the selected image file from the hard disk drive 16 and displays a moving image or a still image on an LCD (Liquid Crystal Display) 19 according to the read SD moving image file SDF, the HD moving image file HDF, or the still image file SF. [0103] The CPU 10 of the HDD video camera 102 is connected to the personal computer 4 via the USB interface 20 and the USB cable 3 ( FIG. 8 ) so that the SD moving image file SDF, the HD moving image file HDF, or the still image file SF can be transferred from the HDD video camera 102 to the personal computer 4 and saved therein, or the SD moving image file SDF, the HD moving image file HDF, or the still image file SF is transferred from the HDD video camera 102 and recorded on a removable recording medium such as a DVD disk or a Blu-ray disk via the personal computer 4 . [0104] The recording media on which to record the SD moving image file SDF, the HD moving image file HDF, or the still image file SF are not limited to the DVD disk and the Blu-ray disk, but other types of recording media such as a HD (High Definition)-DVD disk, a CD-R (Compact Disc-Recordable) disk, or a flash memory may also be used. Circuit Configuration of the Personal Computer [0105] In the second embodiment, the personal computer 4 in the information processing system 101 is similar in circuit configuration to the personal computer 4 according to the first embodiment described above with reference to FIG. 3 , and thus a duplicated explanation thereof is omitted here. Processing Sequence of Writing Data on Disk Depending on the Type of Content Supplied from HDD Video Camera [0106] In the present embodiment, in the state in which the HDD video camera 102 is connected to the personal computer 4 in the information processing system 101 via the USB cable 3 , the HDD video camera 102 set to operate as the slave device is allowed to indirectly control the personal computer 4 serving as the master device such that an SD moving image file SDF or an HD moving image file HDF is transmitted from the HDD video camera 102 to the personal computer 4 and is recorded on a DVD disk or a Blu-ray disk, depending on the type of the image file supplied from the HDD video camera 102 , using the DVD drive 37 of the personal computer 4 . In this processing sequence, a preprocessing is first performed by the HDD video camera 102 as described below with reference to FIG. 11 . Pre-processing Performed by HDD Video Camera [0107] If the CPU 10 of the HDD video camera 102 has started a pre-processing routine at RT 1 in FIG. 11 , the CPU 10 advances the processing flow to step SP 21 . In step SP 21 , if pressing on a “Write on Disk” button (not shown) in an OSD (On Screen Display) menu displayed on the LCD 19 is detected, a content type selection screen SG such as that shown in FIG. 12 for allowing setting of disk writing conditions is displayed on the LCD 19 . The processing flow then proceeds to step SP 22 . [0108] In this content type selection screen SG, a message “Select Content Type To Be Written Using One-Touch Button” is displayed in a lower area, and an “All” button B 1 , an “HD” button B 2 , and an “SD” button B 3 are disposed in a central area. The “All” button B 1 is used to select all image files including SD moving image files SDF, HD moving image files HDF, and still image files SF stored in the HDD video camera 102 as image files to be written on a recording medium by the personal computer 4 . The “HD” button B 2 is used to select HD moving image files HDF and still image files SF as image files to be written on a recording medium by the personal computer 4 . The “SD” button B 3 is used to select SD moving image files SDF and still image files SF as image files to be written on a recording medium by the personal computer. The content type selection screen SG also has a “Back” button B 4 . [0109] The “All” button B 1 , the “HD” button B 2 , and the “SD” button B 3 each have a check box disposed to the right of an icon representing a still image file SF. When this check box is unchecked, still image files SF are not written on a recording medium. [0110] In step SP 22 , if the “All” button B 2 in the content type selection screen SG is selected by a user, the CPU 10 of the HDD video camera 102 describes type information so as to indicate that all image files including SD moving image files SDF, HD moving image files HDF, and still image files SF are specified as image files to be written on a recording medium, and the CPU 10 temporarily stores the type information in the RAM 12 . In a case in which the “HD” button B 2 is selected by a user, the CPU 10 of the HDD video camera 102 describes the type information so as to indicate that HD moving image files HDF and still image files SF are specified as image files to be written and the CPU 10 temporarily stores the type information in the RAM 12 . On the other hand, when the “SD” button B 3 is selected by a user, the CPU 10 of the HDD video camera 102 describes the type information so as to indicate that SD moving image files SDF and still image files SF are specified as image files to be written and the CPU 10 temporarily stores the type information in the RAM 12 . The processing flow then proceeds to step SP 23 and the pre-processing is ended. Processing Sequence of Writing Data on Disk Depending on the Type of Content [0111] After the completion of the pre-processing described above, if the HDD video camera 102 of the information processing system 101 is connected to the personal computer 4 via the USB cable 3 , it becomes possible for the HDD video camera 102 serving as a slave device to indirectly control the personal computer 4 serving as a master device such that a specified combination of SD moving image files SDF, HD moving image files HDF and/or still image files SF stored in the HDD video camera 102 is recorded on a DVD disk or a Blu-ray disk by the DVD drive 37 of the personal computer 4 , depending on the types of contents included in the specified combination of image files, as described in detail below. [0112] As shown in FIG. 13 and FIG. 14 , in step SP 31 , if the CPU 10 of the HDD video camera 102 detects that the HDD video camera 102 is electrically (physically) connected with the personal computer 4 via the USB cable 3 , displays a pop-up window PW 2 such as that shown in FIG. 15 on the LCD 19 ( FIG. 9 ). Thereafter, the processing flow proceeds to a next step SP 32 . [0113] In the present example, a text message “Camera is going to be connected to personal computer” is displayed in the pop-up window PW 2 to indicate that although the HDD video camera 102 is electrically (physically) connected to the personal computer 4 , the HDD video camera 102 is in a state in which the HDD video camera 102 is not yet logically connected to the personal computer 4 , and thus the HDD video camera 102 is not yet set to operate as a slave device of the personal computer 4 and the HDD video camera 102 is allowed to operate independently of the personal computer 4 . [0114] In the pop-up window PW 2 , a “Simply Connect to PC” button P 3 and a “Write on Disk” button P 4 , which are operable in response to touching, are disposed in an area below the text message “Camera is going to be connected to personal computer”. [0115] When the “Simply Connect to PC” button P 3 is selected by a user of the HDD video camera 102 , a SD moving image file SDF, an HD moving image file HDF, and/or a still image file SF taken by the HDD video camera 102 are transferred to the personal computer 4 and stored therein. When the “Write on Disk” button P 4 is selected, the SD moving image file SDF, the HD moving image file HDF, and/or the still image file SF are transferred to the personal computer 4 and recorded on a recording medium such as a DVD disk or a Blu-ray disk. [0116] In step SP 32 the CPU 10 of the HDD video camera 102 determines whether the “Write on Disk” button P 4 in the pop-up window PW 2 has been touched by the user. If the answer to step SP 32 is affirmative, the processing flow proceeds to step SP 33 . [0117] In step SP 33 , in response to the detection, in step SP 32 , of touching to the “Write on Disk” button P 4 by the user, the CPU 10 of the HDD video camera 102 creates a function identification file “OTDISCBN.IND” for causing the personal computer 4 to start the disk writing program and a camera identification file “MODELCFG.IND” in which the type information produced in the pre-processing described above and temporarily stored in the RAM 12 is described, and the CPU 10 of the HDD video camera 102 stores these two files in the hard disk drive 16 . Thereafter, the processing flow proceeds to step SP 34 . [0118] As shown in FIG. 16 , the camera identification file “MODELCFG.IND” described above includes manufacturer information (in one byte) indicating an ID (identification) uniquely assigned to a camera manufacturer described in a filed area, model number information (in one byte indicating a model number uniquely assigned to the HDD video camera 102 described in a model name area, attribute information associated with the HDD video camera 102 , and the type information described in a one-touch button selection area and indicating which one of buttons (the “All” button B 1 , the “HD” button B 2 , and the “SD” button B 3 ) on the content type selection screen SG has been selected by a user. [0119] The CPU 10 of the HDD video camera 102 holds a file system FS 2 in which the function identification file “OTDISCBN.IND” and the camera identification file “MODELCFG.IND” are disposed. As shown in FIG. 17 , this file system FS 2 is located direction below a root direction and in parallel to a “DCIM” folder in which an “AVCHD” folder in which various HD moving image content files are stored, an “MP_ROOT” folder in which various SD moving image content files are stored, and still image files (“DSC0001.JPG”, “DSC00002.JPG”, “DSC00003.JPG”, etc.) are stored. [0120] A “BDMV” folder for storing files associated with Blu-ray disks is formed under the “AVCHD” folder. In this “BDMV” folder, there are stored an index information file “INDEX.BDM” in which information associated with Blu-ray disk images is described, an attribute information file “MOVIEOBJ.BDM”, play list files (“00000.MPL”, “00001.MPL”) clip information files (“01000.CPI”, “02000.CPI”), and HD moving image files HDF (“01000.MTS”, “02000.MTS”). [0121] In an “MP_ROOT” folder for storing various files of SD moving image contents, there are stored content information management files SIF (“INDEX0001.ANP”, “INDEX0001.ANT”, “INDEX0001.ANM”) in which information needed to manage contents, such as a play list, thumbnail images, and meta data, and are described. In a “100PNV01” folder, SD moving image data are stored as SD moving image files SDF with an extension “.MPG” (“M2U00001.MPG”, “M2U00002.MPG”, “M2U00003.MPG”, etc.). [0122] Because the HDD video camera 102 stores the function identification file “OTDISCBN.IND” and the camera identification file “MODELCFG.IND” directly under the root directory, the CPU 30 of the personal computer 4 can directly access the file system FS 2 to read the function identification file “OTDISCBN.IND” and the camera identification file “MODELCFG.IND” without having to go into a deep hierarchical level. This allows it to easily and quickly determine whether or not the function identification file “OTDISCBN.IND” exists and read the content of the camera identification file “MODELCFG.IND”. [0123] When the answer to step SP 32 is negative, that is, when the “Write on Disk” button P 4 is not touched by the user, the CPU 10 of the HDD video camera 102 advances the process to step SP 34 . In step SP 34 , the CPU 10 of the HDD video camera 102 creates the camera identification file “MODELCFG.IND” and advances the process to step SP 35 without producing the function identification file “OTDISCBN.IND”. [0124] The step SP 34 performed in the above-described manner is necessary because even in the case in which the “Write on Disk” button P 4 is not pressed, it is necessary to request the personal computer 4 to treat the HDD video camera 102 not as a simple hard disk drive but as a video camera. Thus, when the HDD video camera 102 is connected to the personal computer 4 , if the personal computer 4 detects the camera identification file “MODELCFG.IND”, the personal computer 4 determines the type of the video camera in accordance with the camera identification file “MODELCFG.IND” and displays a launcher menu screen LMG 2 (described later) corresponding to the type of the video camera. [0125] In step SP 35 , the CPU 10 of the HDD video camera 102 logically connects the HDD video camera 102 to the personal computer 4 . such that the personal computer 4 operates as a master device and the HDD video camera 102 operates as a slave device. The processing flow then proceeds to step SP 36 . [0126] In step SP 36 , if the CPU 30 of the personal computer 4 detects that the HDD video camera 102 has been logically connected to the personal computer 4 , then the processing flow proceeds to a next step SP 37 . [0127] In step SP 37 , the CPU 30 of the personal computer 4 mounts a file system FS 2 of the HDD video camera 102 from the HDD video camera 102 connected to the personal computer 4 via the USB cable 3 . The processing flow then proceeds to step SP 38 . [0128] In step SP 38 , the CPU 30 of the personal computer 4 checks the file system FS 2 of the HDD video camera 102 to determine whether the file system FS 2 includes the function identification file “OTDISCBN.IND”. If the answer to step SP 38 is affirmative, the processing flow proceeds to step SP 39 . [0129] In step SP 39 , because the CPU 30 of the personal computer 4 has detected in the previous step that the file system FS 2 of the HDD video camera 102 includes the function identification file “OTDISCBN.IND”, the CPU 30 of the personal computer 4 automatically starts a DVD writing program stored in the hard disk drive 34 in accordance with an information processing apparatus control program resident in a RAM 22 . Thereafter, the processing flow proceeds to step SP 40 . [0130] In step SP 40 , the CPU 30 of the personal computer 4 reads the content type information described in the one-touch button setting area of the camera identification file “MODELCFG.IND” stored in the RAM 12 of the HDD video camera 102 . The processing flow then proceeds to step SP 41 . [0131] In step SP 41 , the CPU 30 of the personal computer 4 determines, from the content type information, which one of the image file types (the SD moving image files SDF or the HD moving image files HDF) of files stored in the HDD video camera 102 is specified as the image file type of files to be recorded, and the CPU 30 of the personal computer 4 further determines whether to record image files on a Blu-ray disk, which is a disk for recording HD moving image files HDF, according to the specified image file type. [0132] More specifically, when the CPU 30 of the personal computer 4 determines that HD moving image files HDF are specified to be recorded, the CPU 30 determines that the files should be recorded on a Blu-ray disk, which is a disk of the most suitable type for recording HD moving image files. On the other hand, when SD moving image files SDF are specified to be recorded, the CPU 30 of the personal computer 4 determines that the files should be recorded on a DVD disk, which is disk of the most suitable type for recording SD moving image files. [0133] In a case in which it is determined in step SP 41 that the image file to be recorded is not of the HD moving image file HDF but of the SD moving image file SDF, the CPU 30 of the personal computer 4 advances the processing flow to step SP 43 . [0134] On the other hand, when it is determined in step SP 41 that the type of the image file to be recorded is the HD moving image file HDF, the CPU 30 of the personal computer 4 determines that the file should be recorded on a Blu-ray disk, and thus the CPU 30 of the personal computer 4 advances the process to step SP 42 . [0135] In step SP 42 , according to the disk writing program, the CPU 30 of the personal computer 4 requests the HDD video camera 102 to transfer the HD moving image file HDF and the still image file SF. If the HD moving image file HDF and the still image file SF are transmitted to the personal computer 4 from the HDD video camera 2 in response to the request, the received HD moving image file HDF and the still image file SF are recorded on a Blu-ray disk using the DVD drive 27 . The processing flow then proceeds to step SP 43 . [0136] In step SP 43 , the CPU 30 of the personal computer 4 determines, on the basis of the content type information, whether the type of the image file to be recorded is the type of SD moving image file thereby determining whether the image file should be recorded on a DVD disk which is a disk of the most suitable type for recording SD moving image files SDF. [0137] If the answer to step SP 43 is negative, it is determined that the type of the file to be recorded is neither the HD moving image file HDF nor the SD moving image file SDF. In this case, the CPU 30 of the personal computer 4 returns the processing flow to step SP 41 to re-determine the content type. [0138] If the answer to step SP 43 is affirmative, that is, if the type of the image file to be recorded is the SD moving image file SDF, it is determined that the image file should be recorded on a DVD disk. In this case, the processing flow proceeds to step SP 44 . [0139] In step SP 44 , according to the disk writing program, the CPU 30 of the personal computer 4 requests the HDD video camera 102 to transfer the SD moving image file and the still image file SF, and records the SD moving image file and the still image file SF, transmitted from the HDD video camera 102 in response to the request, on a DVD disk in the DVD video format. The processing flow then proceeds to step SP 47 . [0140] In step SP 47 , because the process of writing image files on a disk depending on the content type in response to pressing on the “Write on Disk” button P 4 has been completed, the CPU 10 of the HDD video camera 102 and the CPU 30 of the personal computer 4 release the logical connection between the HDD video camera 102 and the personal computer 4 . As a result, the state is released in which the personal computer 4 operates as the master device and the HDD video camera 102 serves as the slave device. The CPU 30 of the personal computer 4 advances the process to step SP 50 , while the CPU 10 of the HDD video camera 102 advances the process to step SP 48 . [0141] If the logical connection between the personal computer 4 and the HDD video camera 102 has been released and the master-slave relation has been released, then in step SP 48 , the CPU 10 of the HDD video camera 102 deletes the function identification file “OTDISCBN.IND” and the camera identification file “MODELCFG.IND” from the file system FS 2 . The processing flow then proceeds to step SP 49 to end the process. Note that steps SP 47 and SP 48 do not necessarily be executed, but these steps may be executed as required. [0142] Thus, according to the present embodiment, when the HDD video camera 102 is connected to the personal computer 4 via the USB cable, recording is performed in a proper manner according to the intention of the user. [0143] In a case in which the answer to step SP 38 is negative, that is, when the file system FS 2 of the HDD video camera 102 does not include the function identification file “OTDISCBN.IND”, it is not necessary to start the disk writing program, and thus the CPU 30 of the personal computer 4 advances the process to step SP 45 . [0144] In step SP 45 , because the file system FS 2 of the. HDD video camera 102 does not include the function identification file “OTDISCBN.IND” but includes only the camera identification file “MODELCFG.IND”, the CPU 30 of the personal computer 4 starts the default launcher application program according to the information processing apparatus control program. The processing flow then proceeds to step SP 46 . [0145] In step SP 46 , according to the launcher application program, the CPU 30 of the personal computer 4 displays the launcher menu screen LMG 2 such as that shown in FIG. 18 , in which similar parts to those shown in FIG. 7 are denoted by similar reference numeral, on the monitor 36 . This launcher menu screen LMG 2 is similar to the launcher menu screen LMG 1 except that the “One-Touch DVD Writing” button P 11 is replaced with a “One-Touch Disk Writing” button P 21 . [0146] On this launcher menu screen LMG 2 , if the “One-Touch Disk Writing” button P 21 is clicked by a user, the CPU 30 of the personal computer 4 starts the disk writing program and performs the disk writing process depending on the content type ( FIGS. 13 and 14 ). More specifically, the SD moving image file SDF, the HD moving image file HDF, and the still image file SF supplied from the HDD video camera 102 are respectively recorded on a DVD disk or a Blu-ray disk depending on the file type, thereby obtaining a DVD disk and/or a Blu-ray disk on which the SD moving image file SDF, the HD moving image file HDF, and/or the still image file SF are properly recorded. When the “Write on Disk” button P 4 in the pop-up window PW 2 of the HDD video camera 102 is touched, the step SP 33 and following steps are performed. [0147] Note that the CPU 30 of the personal computer 4 records only SD moving image files SDF, HD moving image files HDF, and/or still image files SF which have not yet recorded on a recording medium. If no such image files are found in the HDD video camera 102 , an error message is displayed to inform the user of that there is no new file to be recorded. [0148] When the “Differential PC Backup” button P 12 is touched by a user, the CPU 30 of the personal computer 4 determines whether the HDD video camera 102 includes new SD moving image files SDF, HD moving image files HDF, and/or still image files SF which have not yet been stored in the personal computer 4 . If such image files are detected, only the detected image files are stored on the hard disk drive 34 of the personal computer 4 or on a DVD disk or a Blu-ray disk. If there is no difference between image files stored in the HDD video camera 102 and image files captured by the personal computer 4 , an error message is displayed to inform the user of this fact. [0149] When the “Vie Image” button P 13 on the launcher menu screen LMG 2 is clicked by a user, the CPU 30 of the personal computer 4 displays an image of the SD moving image file SDF, the HD moving image file HDF, or the still image file. SF captured from the HDD video camera 102 or an image of an image file downloaded from a site on the Internet. [0150] When the “DVD Authoring” button P 14 is clicked by a user, the CPU 30 of the personal computer 4 allows the user to edit the SD moving image file SDF, the HD moving image file HDF, or the still image file SF into a desired form in which to record the image file on a DVD disk or a Blu-ray disk. In this case, the SD moving image file SDF, the HD moving image file HDF, or the still image file SF supplied from the HDD video camera 102 is not directly recorded on a DVD disk or a Blu-ray disk but recorded after being edited. [0151] When the “Play List” button P 15 is clicked by a user, the CPU 30 of the personal computer 4 records the SD moving image file SDF, the HD moving image file HDF, and/or the still image file SF on a DVD disk or a Blu-ray disk in the order specified in the play list stored in the HDD video camera 102 . If the HDD video camera 102 has the play list, the CPU 30 of the personal computer 4 converts the still image file SF compressed in the PEG form into an MPEG2 form so that the still image file SF is allowed to be recorded in the same form as that of the SD moving image file SDF or the HD moving image file HDF, and then the specified image files are recorded on a DVD disk or a Blu-ray disk. When there is no play list, the still image file SF in the JPEG form is directly recorded on a DVD disk or a Blu-ray disk. [0152] That is, when there is a play list, the CPU 30 of the personal computer 4 records the SD moving image file SDF, the HD moving image file HDF, and/or the still image file SF in accordance with the play list on a DVD disk or a Blu-ray disk after converting the still image SF compressed in the JPEG form into the MPEG2 form so that all image files are in the MPEG2 form. This makes it possible even for an optical disk player capable of playing back only MPEG2 moving images to play back still images SF. [0153] In the case in which there is no play list and thus the JPEG still image is directly recorded on a DVD disk or a Blu-ray disk by the CPU 30 of the personal computer 4 , if an optical disk player is capable of playing back still image files, it is possible to also read still image file SF and display an image on the monitor 36 according to the still image file SF. [0154] When the “Settings” button P 16 is clicked by a user, the CPU 30 of the personal computer 4 allows the user to modify the details of settings of conditions under which to record the SD moving image file SDF, the HD moving image file HDF, and/or the still image file SF on a DVD disk or a Blu-ray disk. When the “Close” button P 17 is clicked by a user, the launcher menu screen LGM 2 is closed. Operation and Advantages of the Second Embodiment [0155] In the information processing system 101 configured in the above-described manner according to the second embodiment, when the “Write on Disk” button P 4 in the pop-up window PW 2 displayed on the LCD 19 of the HDD video camera 102 is touched by a user, the function indemnification file “OTDISCBN.IND” is created and stored on the hard disk drive 16 . Furthermore, the camera identification file “MODELCFG.IND” is created in which type information indicating the content type to be recorded by the personal computer 4 , and the created camera identification file “MODELCFG.IND” is stored on the hard disk drive 16 . [0156] At this stage of the processing, the HDD video camera 102 has completed the pre-process necessary to indirectly control the personal computer 4 . When the HDD video camera 102 is logically connected to the personal computer 4 , if the personal computer 4 detects the function identification file “OTDISCBN.IND” stored in the HDD video camera 102 , then, according to the information processing apparatus control program, the personal computer 4 starts the disk writing program, captures the SD moving image file SDF, the HD moving image file HDF, or the still image file SF according to the type information described in the camera identification file “MODELCFG.IND”, and records the captured image file on a DVD disk or a Blu-ray disk depending on the image file type. [0157] Thus, in the state in which the HDD video camera 102 is logically connected to the personal computer 4 such that the HDD video camera 102 operates as a slave device and the personal computer 4 operates as a master device and thus the HDD video camera 102 operating as the slave device is not allowed to directly issue a write-on-disk command to the personal computer 4 , use of the function identification file “OTDISCBN.IND” and the camera identification file “MODELCFG.IND” makes it possible for the HDD video camera 102 to indirectly control the personal computer 4 to record a specified content on a DVD disk or a Blu-ray disk depending on the content type. That is, the same effect as that achieved by directly issuing the write-on-disk command to the personal computer 4 can be achieved indirectly. [0158] Thus, the user of the HDD video camera 102 is allowed to transfer the SD moving image file SDF, the HD moving image file HDF, and/or the still image file SF to the personal computer 4 and write them on a DVD disk or a Blu-ray disk simply by touching a button on the HDD video camera 102 without having to operate the personal computer 4 or install a special driver software program on the personal computer 4 . [0159] When the CPU 30 of the personal computer 4 determines that the file system FS 2 of the HDD video camera 102 does not include the function identification file “OTDISCBN.IND”, the CPU 30 of the personal computer 4 displays on the display 36 the launcher menu screen LMG 2 corresponding to the camera identification file “MODELCFG.IND”. Thus, it is possible to regard that a command to display the launcher menu screen LMG 2 is indirectly issued from the HDD video camera 102 to the personal computer 4 . [0160] When the CPU 30 of the personal computer 4 detects that the “One-Touch Disk Writing” button P 21 on the launcher menu screen LMG 2 has been clicked, the CPU 30 of the personal computer 4 reads the SD moving image file SDF, the HD moving image file HDF, and/or the still image file SF from the HDD video camera 102 and records them on a DVD disk or a Blu-ray disk thereby obtaining the DVD disk or the Blu-ray disk on which the files have been recorded. Thus, in the information processing system 101 , the operation of writing files on a DVD disk or a Blu-ray disk can be initiated by either the video camera 102 or the personal computer 4 . This provides a great improvement in usability. [0161] When the CPU 30 of the personal computer 4 determines that the HDD video camera 102 has an SD moving image file SDF, an HD moving image file HDF, and/or a still image file SF which have not yet been recorded by the personal computer 4 , the CPU 30 of the personal computer 4 can additionally record only these files on a DVD disk or a Blu-ray disk. This prevents the same content as that already existing on the DVD disk or the Blu-ray disk from being recorded in a duplicated manner. Thus, it is possible to use recording media in an efficient manner. [0162] In the information processing system 101 , as described above, even in the state in which the personal computer 4 is set to serve as a master device and the HDD video camera 102 is set to serve as a slave device after they have been connected to each other, a user is allowed to, simply by touching a button on the HDD video camera 102 , transfer an SD moving image file SDF, an HD moving image file HDF, and/or a still image file SF from the HDD video camera 102 to the personal computer 4 and write them on a DVD disk or a Blu-ray disk suitable for recording the files depending on the content type thereby easily obtaining a DVD disk or a Blu-ray disk on which the files have been recorded. Other Embodiments [0163] In the information processing system 1 according to the first embodiment described above, it is assumed that the moving image file DF and/or the still image file SF to be recorded are supplied to the personal computer 4 from the hard disk drive 16 disposed in the inside of the of the HDD video camera 2 . Alternatively, image files to be recorded may be supplied to the personal computer 4 from another type of recording medium such as a removable video tape, a DVD disk, or a semiconductor memory mounted on a video camera. [0164] In the information processing system 101 according to the second embodiment described above, it is assumed that the SD moving image file SDF, the HD moving image file HDF, and/or the still image file SF to be recorded on a Blu-ray disk or a DVD disk are supplied to the personal computer 4 from the hard disk drive disposed in the inside of the HDD video camera 102 . Alternatively, the SD moving image file SDF, the HD moving image file HDF, and/or the still image file SF to be recorded may be supplied to the personal computer 4 from another type of recording medium such as a high-capacity storage disk or a high-capacity semiconductor memory mounted on a video camera. [0165] In the first and second embodiments described above, it is assumed that the hard disk drive 16 is firmly disposed in the inside of the HDD video camera 2 or 102 . Alternatively, the hard disk drive 16 may be removably attached to the video camera 2 or 102 . [0166] In the first embodiment described above, when the “Write on DVD” button P 2 in the pop-up window PW 1 is touched by a user, the HDD video camera 2 produces the function identification file “DVDBURN.IND” which causes the personal computer 4 to start the process of writing files on a DVD disk. Alternatively, for example, a “Memory Stick (trademark of Sony Corp.) Writing” button may be disposed in the pop-up window PW 1 so that when the “Memory Stick Writing” button is pressed, a function identification file for causing the personal computer 4 to perform a process of writing files in a memory stick may be produced and stored. [0167] In the first embodiment described above, the “Write on DVD” button P 2 is displayed in the pop-up window PW 1 so that a user is allowed to operate it by touching it. Alternatively, the “Write on DVD” button P 2 may be formed by hardware on a case of the HDD video camera 2 so that a user is allowed to operate it by pressing it. [0168] In the second embodiment described above, the “Write on Disk” button P 4 is displayed in the pop-up window PW 2 so that a user is allowed to operate it by touching it. Alternatively, a “Write on Disk” button may be formed by hardware on a case of the HDD video camera 102 so that a user is allowed to operate it by pressing it. [0169] In the first and second embodiments described above, when the HDD video camera 2 or 102 is electrically (physically) connected to the personal computer 4 , the pop-up window PW 1 or PW 2 is displayed on the LCD 16 of the HDD video camera 2 or 102 . Alternatively, the pop-up window PW 1 or PW 2 may be displayed on the LCD 19 when a button in a menu is touched even in a state in which the HDD video camera 2 or 102 is not electrically (physically) connected to the personal computer 4 , and the HDD video camera 2 or 102 may produce the function identification file “DVDBURN.IND” or “OTDISCBN.IND” when a button in the pop-up window PW 1 or PW 2 is touched. [0170] In the first and second embodiments described above, when the CPU 30 of the personal computer 4 detects the presence of the function identification file “DVDBURN.IND” in the file system FS 1 of the HDD video camera 2 or the presence of the function identification file “OTDISCBN.IND” in the file system FS 2 of the HDD video camera 102 , the DVD writing program or the disk writing program stored in the hard disk drive 24 is started by the information processing apparatus control program resident in the RAM 22 . Alternatively, the information processing apparatus control program may be installed from a storage medium such as a CD-ROM or a DVD disk or may be downloaded from a site on the Internet. [0171] In the first and second embodiments described above, the information processing system 1 or 101 is formed by connecting the personal computer 4 serving as the information processing apparatus to the HDD video camera 2 or 102 serving ass the slave device. Alternatively, an information processing system may be formed by connecting an information processing apparatus capable of executing various application programs to realize various functions, such as a portable telephone device or a PDA (Personal Digital Assistant) device, to an electronic apparatus serving as a content output apparatus capable of taking an image and outputting it such as a portable telephone device, a PDA device, or a notebook personal computer. [0172] In the first embodiment described above, a moving image file DF is transferred as content data from the HDD video camera 2 to the personal computer 4 and is recorded on a DVD disk. Alternatively, other types of data such as a still image file, an audio file, a gram program file, a text file, etc. may be transferred to the personal computer 4 and recorded on a DVD disk. [0173] In the second embodiment described above, an SD moving image file SDF, an HD moving image file HDF, and/or a still image file SF are transferred as content data from the HDD video camera 102 to the personal computer 4 and recorded on a DVD disk or a Blu-ray disk depending on the content type. Alternatively, other types of data such as an audio file, a gram program file, a text file, etc. may be transferred to the personal computer 4 and recorded on a DVD disk and may be recorded on a DVD disk or a Blu-ray disk depending on the data size or the data format. [0174] In the first embodiment described above, after the HDD video camera 2 is electrically (physically) connected to the personal computer 4 , when the “Write on DVD” button P 2 is touched, the function identification file “DVDBURN.IND” is created. Alternatively, when the “Write on DVD” button P 2 is touched at an arbitrary time before or after the HDD video camera 2 is electrically (physically) connected to the personal computer 4 , the function identification file “DVDBURN.IND” may be created. [0175] In the second embodiment described above, after the HDD video camera 102 is electrically (physically) connected to the personal computer 4 , when the “Write on Disk” button P 4 is touched, the function identification file “OTDISCBN.IND” and the camera identification file “MODELCFG.IND” are created. Alternatively, when the “Write on Disk” button P 4 is touched at an arbitrary time after or before the HDD video camera 102 is electrically (physically) connected to the personal computer 4 , the function identification file “OTDISCBN.IND” and the camera identification file “MODELCFG.IND” may be created. [0176] In the second embodiment described above, the determination is made in step SP 40 as to whether the content data should be recorded on a Blu-ray disk, which is a disk of the type suitable for recording an HD moving image file HDF, and the determination is further made in step SP 42 as to whether the content data should be recorded on a DVD disk, which a disk of the type suitable for recording an SD moving image file SDF. Alternatively, the determination in step SP 42 may be made first and then the determination in step SP 40 may be made. [0177] In the first and second embodiments described above, when the HDD video camera 2 or 102 has a play list, still image files SF compressed in the JPEG form are converted into the MPEG2 form and recorded together with other image files in the MPEG2 form, while JPEG still image files SF are directly recorded without being converted into the MPEG2 form when there is no play list. Alternatively, regardless of whether there is a play list, still image files SF compressed in the JPEG form may be converted into the MPEG2 form before being recorded or may be directly recorded without being converted. [0178] In the first and second embodiments described above, the HDD video camera 2 or 102 serving as the content output apparatus is assumed to be configured so as to include the CPU 10 serving as the function identification file creation means and the type identification file generation means and so as to include the RAM 12 serving as the file storage means, while the personal computer 4 serving as the information processing apparatus is assumed to be configured so as to include the USB interface 28 serving as the detection means and the CPU 30 serving as the control means. Alternatively, one or all of the function identification file creation means, the type identification file generation means, and the file storage means in the content output apparatus may be realized in another circuit configuration, and one or both of the detection means and the control means of the information processing apparatus may be realized in another circuit configuration. [0179] It should be understood by those skilled in the art that various modifications, combinations, sub-combinations and alterations may occur depending on design requirements and other factors insofar as they are within the scope of the appended claims or the equivalents thereof.

In an information processing system including an information processing apparatus and a content output apparatus which are connected to each other, the content output apparatus is configured to include a function identification file creation unit adapted to, in accordance with a button operation by a user, create a function identification file for causing the information processing apparatus to execute a predetermined function, and a file storage unit adapted to store the function identification file in a storage unit, and the information processing apparatus is configured to include a detector adapted to detect a connection of the content output apparatus to the information processing apparatus, and a controller adapted to, after detecting the connection of the content output apparatus, start an application program to execute the function depending on the presence/absence of the function identification file in the storage unit.

CLAIM OF PRIORITY [0001] The present application claims priority from Japanese application serial no. 2005-367862, filed on Dec. 21, 2005, the content of which is hereby incorporated by reference into this application. FIELD OF THE INVENTION [0002] The present invention relates to a DC-DC converter that is provided between a first voltage power supply and a second voltage power supply and performs forward power conversion from a first voltage to a second voltage and backward power conversion from the second voltage to the first voltage. BACKGROUND OF THE INVENTION [0003] With a background of social problems such as global warming and an increase in crude oil prices, there is a rapid spread of hybrid electric vehicles (HEVs) and other vehicles targeted at a high mileage. In general, an HEV includes a main high-voltage battery for driving an engine assisting motor and an auxiliary low-voltage battery for supplying electric power to electronic devices mounted on the vehicle. The main high-voltage battery is charged when the engine rotates the motor and produces (regenerates) electric power. The generated electric power is converted by a DC-DC converter to electric power for the auxiliary low-voltage battery and supplied to the vehicle-mounted electronic devices. Thus, the main purpose of the DC-DC converter disposed between the main high-voltage battery and the auxiliary low-voltage battery is to cause a step-down operation from the main high-voltage battery to the auxiliary low-voltage battery. However, there is also a need to cause a step-up operation from the auxiliary low-voltage battery to the main high-voltage battery. For example, the engine may not be capable of being started due to a low voltage of the main high-voltage battery. In this case, if electric power can be supplied from the auxiliary low-voltage battery to the main high-voltage battery, the auxiliary low-voltage battery can compensate for the power insufficiency to start the engine through the main high-voltage battery alone. Accordingly, a bi-directional DC-DC converter having both a step-down function that serves from the high-voltage side to the low-voltage side and a step-up function that serves from the low-voltage side to the high-voltage side is demanded. [0004] Examples of the prior art related to this type of bi-directional DC-DC converter are disclosed in, for example, Patent Documents 1 to 3. [0005] Patent Document 1: Japanese Patent Laid-open No. 2003-111413 [0006] Patent Document 2: Japanese Patent Laid-open No. 2002-165448 [0007] Patent Document 3: Japanese Patent Laid-open No. 11(1999)-8910 SUMMARY OF THE INVENTION [0008] Suppose that a step-down ratio and a step-up ratio are determined by a ratio between the number of turns on the primary side of a transformer and the number of turns on the secondary side. If a ratio of the number of turns on the transformer that is optimum for a step-down operation is set, a problem of the inability to meet a step-up ratio arises. Conversely, if the step-up ratio is focused in setting a ratio of the number of turns on the transformer, another problem of a too low voltage during a step-down operation occurs. Even if a bi-directional DC-DC converter is structured without a transformer, when a difference between the step-down ratio and the step-up ratio is relatively large, desired bi-directional voltage ratios cannot be obtained easily. [0009] An object of the present invention is to provide a DC-DC converter, for bi-directionally converting electric power between two different voltages, from which a voltage is obtained across two terminals in a desired range even when a difference between its step-down ratio and step-up ratio is needed. [0000] [Means of Solving the Problems] [0010] With a usual switching power supply, the step-down ratio and step-up ratio can be adjusted by adjusting the duty ratio of a pulse width modulation (PWM) signal (a pulse frequency modulation (PFM) signal may be used instead, which is also true for the description that follows) that controls the switching device. When a transformer is used, the step-down ratio and step-up ratio can be determined by the ratio between the number of turns on the primary side of the transformer and the number of turns on the secondary side. However there may be a large difference between a demanded step-down ratio (N 1 ) and step-up ratio (N 2 ). In this case, the above-mentioned PWM control and transformer turns ratio alone may be insufficient. [0011] In a preferred mode of the present invention, there is a difference in duty ratio range in PWM control between the step-down operation and the step-up operation. [0012] As well known, the duty ratio in PWM control cannot be adjusted over a range from 0% to 100% due to restrictions on the minimum turned-on and turned-off times of a switching device. An allowable range of the duty ratio is, for example, 5% to 95%. Since the minimum turned-on and turned-off times of the switching device are unchangeable, when the switching frequency is lowered to prolong the cycle, the allowable duty ratio range can be widened accordingly. It is possible to obtain an allowable duty ratio range of, for example, 3% to 97%. Therefore, the easiest method of adjusting the duty ratio range is to adjusting the switching frequency. [0013] In the preferred mode of the present invention, a means for setting a duty ratio range for the step-down operation and a duty ratio range in the step-up operation separately is provided. [0014] In another preferred mode of the present invention, a DC-DC converter, which includes a transformer that connects a step-down conversion circuit and a step-up conversion circuit and converts electric power between two voltages, has a turns ratio switching means for switching the turns ratios of the transformer between the step-down operation and the step-up operation. [0015] According to the preferred mode of the present invention, the duty ratio range in PWM control can be adjusted independently for the step-down operation and the step-up operation by making a switching frequency during the step-down operation different from, for example, a switching frequency during the step-up operation. Accordingly, when the frequency for the step-down ratio or step-up ratio, whichever is insufficient, is set to a value lower than the frequency for the other (the cycle, that is, the length of time of one cycle, is prolonged) to expand the duty ratio range in PWM control, the adjustable range of the step-down ratio or the step-up ratio can be expanded. Of course, it is also possible to use a duty ratio range adjusting means other than to adjust the switching frequency. [0016] According to the other preferred mode of the present invention, since there is provided a means for using a different transformer turns ratio between the primary side and the secondary side depending on whether the voltage is dropped or boosted when a single transformer is used to drop and boost the voltage, transformer turns ratios optimum for the step-down ratio and step-up ratio can be set. As a result, the adjustable range of the step-down ratio or step-up ratio can be expanded. [0017] These two types,of techniques can be used separately or together, enabling the range of the step-down ratio or step-up ratio to be expanded. [0018] Other purposes and features of the present invention will be clarified in the description of embodiments that follow. BRIEF DESCRIPTION OF THE DRAWINGS [0019] FIG. 1 shows the entire structure of a bi-directional DC-DC converter according to a first embodiment of the present invention. [0020] FIG. 2 illustrates the relation between the step-down ratio and the step-up ratio of the bidirectional DC-DC converter. [0021] FIG. 3A shows first example of the structure of the switching frequency setting and adjusting means in the first embodiment of the present invention. [0022] FIG. 3B shows second example of the structure of the switching frequency setting and adjusting means in the first embodiment of the present invention. [0023] FIG. 3C shows third example of the structure of the switching frequency setting and adjusting means in the first embodiment of the present invention. [0024] FIG. 4 shows a specific example of the structure of the step-down control circuit in the first embodiment. [0025] FIG. 5A illustrates first relation between the frequencies set by the switching frequency setting means. [0026] FIG. 5B illustrates second relation between the frequencies set by the switching frequency setting means. [0027] FIG. 6 shows the entire structure of a bi-directional DC-DC converter according to a second embodiment of the present invention. [0028] FIG. 7 shows the entire structure of a bi-directional DC-DC converter according to a third embodiment of the present invention. [0029] FIG. 8 shows the entire structure of a bi-directional DC-DC converter according to a fourth embodiment of the present invention. [0030] FIG. 9 shows the entire structure of a bi-directional DC-DC converter according to a fifth embodiment of the present invention. [0031] FIG. 10 shows the entire structure of a bi-directional DC-DC converter according to a sixth embodiment of the present invention. [0032] FIG. 11 shows the entire structure of a bi-directional DC-DC converter according to a seventh embodiment of the present invention. [0033] FIG. 12 shows the entire structure of a bi-directional DC-DC converter according to an eighth embodiment of the present invention. [0034] FIG. 13 shows an example of timing charts when a step-down operation is performed in FIG. 12 . [0035] FIG. 14 shows an example of timing charts when a step-down operation is performed in FIG. 12 . [0036] FIG. 15 shows the entire structure of a bi-directional DC-DC converter according to a ninth embodiment of the present invention. [0037] FIG. 16 shows the entire structure of a bi-directional DC-DC converter according to a tenth embodiment of the present invention. [0038] FIG. 17 shows the entire structure of a bi-directional DC-DC converter according to an eleventh embodiment of the present invention. [0039] FIG. 18 shows the entire structure of a bi-directional DC-DC converter according to a twelfth embodiment of the present invention. [0040] FIG. 19 shows the entire structure of a bi-directional DC-DC converter according to a thirteenth embodiment of the present invention. [0041] FIG. 20 shows examples of timing charts during a step-down operation and step-up operation in the thirteenth embodiment in FIG. 19 . [0042] FIG. 21 shows, as a fourteenth embodiment of the present invention, a system structure in which a bi-directional DC-DC converter is applied to a vehicle-mounted hybrid system. DESCRIPTION OF THE PREFERRED EMBODIMENTS [0043] In, for example, a DC-DC converter that has two batteries with two different voltages and bi-directionally converts electric power between the two voltages, the voltage range of the main high-voltage battery is determined according to the secondary battery mounted, required system specifications, and other factors. The voltage range of the auxiliary low-voltage battery is also determined similarly. [0044] FIG. 2 shows a step-down ratio and step-up ratio when electric power conversion is performed between two different voltages, high voltage and low voltage. The largest difference between N 1 of the step-down ratio 1/N 1 and the step-up ratio N 2 may be present in FIG. 2 . The step-down ratio 1/N 1 during the step-down operation from the high-voltage side to the low-voltage side is defined as 1/N 1 =1/(HV 1 /LV 2 ), and the step-up ratio N 2 during the step-up operation from the low-voltage side to the high-voltage side is defined as HV 2 /LV 1 . If N 1 of the step-down ratio 1/N 1 is relatively close to the step-up ratio N 2 , a bi-directional DC-DC converter can be designed with ease. However, HV 1 , HV 2 , LV 1 , and LV 2 vary according to the charted states of the two batteries, battery deterioration states, and other conditions, so there may be often a large difference between N 1 and N 2 , making the design difficult. Preferred embodiments of the present invention that addresses this problem will be described below in detail with reference to the drawings. First Embodiment [0045] FIG. 1 shows the entire structure of a bi-directional DC-DC converter according to a first embodiment of the present invention. The main circuits in FIG. 1 are a high-voltage DC power supply HV, a low-voltage DC power supply LV, a main high-voltage circuit 1 having a switching means, and a main low-voltage circuit 2 having a switching means, and a transformer 3 . [0046] Provided as control circuits are a step-down control circuit 4 for dropping the voltage from the HV side to the LV side, a step-up control circuit 5 for boosting the voltage, a switching frequency setting means 6 for a switching signal generated by the step-down control circuit 4 , and a frequency setting means 7 for the step-up control circuit 5 . Selectors 8 and 9 are also included; the selector 8 selectively selects a control signal sent from the step-down control circuit 4 and a control signal sent from the step-up control circuit 5 and sends the selected signal to the main high-voltage circuit 1 ; the selector 9 selectively selects a control signal sent from the step-down control circuit 4 and a control signal sent from the step-up control circuit 5 and sends the selected signal to the main low-voltage circuit 2 . [0047] The above components excluding the power supplies HV and LV constitute the bi-directional DC-DC converter 10 . [0048] The bi-directional DC-DC converter 10 is structured so that a step-down/step-up control switching signal 12 is received from a high-end controller 11 such as engine controller. [0049] Next, operation in FIG. 1 will be described. In the step-down operation from the high-voltage DC power supply HV to the low-voltage DC power supply LV, a DC voltage of the HV is converted to an AC voltage in the main high-voltage circuit 1 , the AC voltage is transferred to the LV by the transformer 3 , and the transferred AC voltage is rectified in the main low-voltage circuit 2 . At this time, the switching means in the main high-voltage circuit 1 and main low-voltage circuit 2 are controlled by control signals generated by the step-down control circuit 4 and selected by the selectors 8 and 9 . The step-down/step-up control switching signal 12 sent from the high-end controller 11 and input to the selectors 8 and 9 commands a step-down operation. The step-down control circuit 4 generates control signals to be supplied to the switching means according to the switching frequency set by the switching frequency setting means 6 . [0050] During the step-down operation, the step-up control circuit 5 and switching frequency setting means 7 may or may not operate because they do not affect the step-down operation. To reduce the power consumption, however, the step-up control circuit 5 and switching frequency setting means 7 are preferably stopped. As such, the step-down operation from the high-voltage DC power supply HV to the low-voltage DC power supply LV is performed. [0051] In the step-up operation from the low-voltage DC power supply LV to the high-voltage DC power supply HV, the DC voltage of the LV is converted into an AC voltage in the main low-voltage circuit 2 . The converted AC voltage is transferred by the transformer 3 to the HV and then rectified in the main high-voltage circuit 1 . At this time, the switching means in the main low-voltage circuit 2 and main high-voltage circuit 1 are controlled by control signals generated in the step-up control circuit 5 and selected by the selectors 8 and 9 . The step-down/step-up control switching signal 12 input from the selectors 8 and 9 from the high-end controller 11 commands a step-up operation. The step-up control circuit 5 generates controls signals to be supplied to the switching means, according to the switching frequency set by the switching frequency setting means 7 . [0052] During the step-up operation, the step-down control circuit 4 and switching frequency setting means 6 may or may not operate because they do not affect the step-up operation. To reduce the power consumption, however, the step-down control circuit 4 and switching frequency setting means 6 are preferably stopped. As such, the step-up operation from the low-voltage DC power supply LV to the high-voltage DC power supply HV is performed. [0053] The main high-voltage circuit 1 operates as an inverter that converts a DC voltage into an AC voltage during the step-down operation and as a rectifier that converts an AC voltage into a DC voltage during the step-up operation. The main low-voltage circuit 2 operates as a rectifier that converts an AC voltage into a DC voltage during the step-down operation and as an inverter that converts a DC voltage into an AC voltage during the step-up operation. [0054] The switching means included in the main high-voltage circuit 1 and main low-voltage circuit 2 may be operated by diodes alone that are connected in parallel according to the operation, without having them perform a switching operation. This is because, during the rectification operation, for example, rectification by the diodes can basically achieve the purpose. When the switching means is turned on actively during the rectification operation, its purpose is usually to perform synchronous rectification with a switching device with less loss than the diode. [0055] Next, the relation among the step-down ratio, the step-up ratio, the turns ratios of the transformer, and switching frequencies fsw 1 and fsw 2 will be described with reference again to FIG. 2 . [0056] FIG. 2 illustrates the relation between the voltage range (HV 1 to HV 2 ) of the high-voltage DC power supply HV and the voltage range (LV 1 to LV 2 ) of the low-voltage power supply LV. In the step-down operation, the step-down ratio (indicated by N 1 ) is minimized when the HV is at the lowest voltage (HV 1 ) and the LV is at the highest voltage (LV 2 ). In the step-up operation, the step-up ratio (indicated by N 2 ) is maximized when the LV is at the lowest voltage (LV 1 ) and the HV is at the highest voltage (HV 2 ). [0057] When there is a large difference between the step-down ratio and the step-up ratio, as described above, a significant design parameter in FIG. 1 is the turns ratio of the transformer. When both the step-down operation from the HV to LV and the step-up operation from the LV to the HV are performed, the step-down ratio and step-up ratio are largely affected by the turns ratio of the transformer because the transformer is shared by the main high-voltage circuit 1 and main low-voltage circuit 2 . If the turns ratio, for example, is determined with the step-down operation prioritized, a sufficient step-up ratio may not be obtained. Conversely, if the turns ratio is determined with the step-up operation prioritized, a sufficient step-down ratio cannot be obtained, resulting in a too low LV voltage. [0058] In this embodiment, the above-mentioned switching frequencies during the step-down and step-up operations are set independently, so the step-down and step-up ratios can be set in a wide range. The switching frequencies fsw 1 and fsw 2 respectively set in the switching frequency setting means 6 and 7 are factory-set to unique values; they may be left unchanged after the product is shipped or may be changed during an operation after the shipping, according to the voltages of the HV and LV, the value of the load current (large or small), or another factor. [0059] FIGS. 3A to 3 C show an example of the structure of the switching frequency setting means in the first embodiment. [0060] In FIG. 3A , switches 311 to 313 , used as the switching means of the switching frequency setting means 6 and 7 , selectively select resistors 321 to 323 , respectively, to change the frequency fsw of an oscillator 310 . In FIG. 3B , a plurality of oscillators 331 to 333 with different frequencies are provided; to change the output frequency fsw, one oscillator is selected with a switch 341 , 342 , or 343 . In FIG. 3C , the signal frequency of a discrete component, such as a carrier oscillator, in a PWM modulator 350 is adjusted by selecting the constant of an external component, such as the capacitance of a capacitor 361 , 362 , or 363 , with a switch 371 , 372 , or 373 . [0061] FIG. 4 shows a specific example of the structure of the step-down control circuit according to the first embodiment. FIG. 4 is the same as FIG. 1 except that the structure of the control system of the step-down control circuit 4 is depicted in detail. An error amplifier 111 amplifies the difference between the voltage of the low-voltage DC power supply LV and a reference voltage 112 and sends the amplified error to a PWM modulator (or PFM modulator) 110 . The PWM modulator 110 performs PWM modulation (or PFM modulation) on the amplified result received from the error amplifier 111 and sends the resulting signal to the switching means in the main high-voltage circuit 1 and main low-voltage circuit 2 . Although the step-up control circuit 5 in FIG. 1 is omitted in FIG. 4 , it has the same structure as the step-down control circuit 4 except that the step-up control circuit 5 receives a voltage from the high-voltage DC power supply HV and outputs it to terminals, on the selectors 8 and 9 , not used by the step-down control circuit 4 . [0062] FIG. 5A illustrates first relation between the turns ratio of the transformer 3 and the frequencies fsw 1 and fsw 2 set by the switching frequency setting means 6 and 7 . In FIG. 5A , the transformer turns ratio (N 1 ) required for dropping the voltage and the transformer turns ratio (N 2 ) required for boosting the voltage are indicated on the horizontal axis. There is no problem if transformer turns ratios that satisfy the conditions for both the step-down and step-up operations are selected. When losses in the transformer, the switching device, and other circuits are considered, it is difficult to satisfy both conditions. In this case, either the step-down or step-up operation must be prioritized when transformer turns ratios are determined. When the switching frequency fsw 1 during the step-down operation and the switching frequency fsw 2 during the step-up operation are set as shown in FIG. 5A , the step-up and step-down ratios, which are difficult to satisfy simultaneously with only the transformer turns ratio, can be satisfied. [0063] FIG. 5B illustrates second relation between the turns ratio of the transformer 3 and the frequencies fsw 1 and fsw 2 set by the switching frequency setting means 6 and 7 . Especially, FIG. 5B shows an example in which the transformer turns ratios obtained from calculations of the step-down and step-up ratios cannot be originally satisfied simultaneously. In this case as well, either the step-down or step-up operation must be prioritized when transformer turns ratios are determined. When the switching frequencies fsw 1 and fsw 2 are set as shown in FIG. 5B , the step-down and step-up ratios can be set in as wide a range as possible. [0064] Now, the relation between the step-up ratio and the transformer turns ratio required for the step-up operation will be described. During the step-up operation, the main low-voltage circuit is operated as the step-up circuit. The product (N 2 _ 1 ×N 2 _ 2 ) of the step-up ratio N 2 _ 1 of the step-up circuit and the transformer turns ratio N 2 _ 2 is used to satisfy the step-up ratio. In this type of example, the transformer turns ratio N 2 _ 2 actually required for the step-up operation is N 2 _ 2 N 2 /N 2 _ 1 . The transformer turns ratio N 2 _ 2 required for the step-up operation that has been described refers to the step-up ratio required for the transformer itself (in this case, the step-up ratio is N 2 _ 2 ). [0065] As described above, if the switching frequency is reduced and the length of one cycle is prolonged, the duty ratio width in PWM control can be expanded, widening the step-down or step-up ratio range. [0066] According to this embodiment, in a bi-directional DC-DC converter that cannot satisfy both step-down and step-up ratios simultaneously, a switching frequency selected during a step-down operation and a switching frequency selected during a step-up operation are set independently to different values. A resulting effect is that the step-down and step-up ratios can be set in a wide range. Another effect is that since one more design parameter is used in a design of a bi-directional DC-DC converter, the design can be completed more quickly. Second Embodiment [0067] FIG. 6 shows the entire structure of a bi-directional DC-DC converter according to a second embodiment of the present invention. The functional parts in FIG. 6 that are identical to the corresponding ones in FIG. 1 are assigned the same reference numerals to eliminate duplicate description. FIG. 6 differs from FIG. 1 in that a switching circuit 13 that switches between the switching frequencies fsw 1 and fsw 2 is provided. A switching frequency setting means 14 sets the switching frequency fsw 1 according to an fsw 1 switching signal 16 from the switching circuit 13 . A switching frequency setting means 15 sets the switching frequency fsw 2 according to an fsw 2 switching signal 17 from the switching circuit 13 . The switching circuit 13 is structured so that it receives the step-down/step-up control switching signal 12 sent from the high-end controller 11 , a voltage signal 18 from the high-voltage DC power supply HV, and a voltage signal 19 from the low-voltage DC power supply LV. This completes the description of the structure of the bi-directional DC-DC converter 20 . [0068] The basic operation in the second embodiment is similar to the one in the first embodiment in FIG. 1 . Operations different from FIG. 1 will be described below. In FIG. 1 , the switching frequencies fsw 1 and fsw 2 cannot be changed during operation; in FIG. 6 , however, they can be changed. Specifically, the switching frequency fsw 1 /fsw 2 switching circuit 13 calculates a step-down or step-up ratio at that time from the voltage 18 of the high-voltage DC power supply HV and the voltage 19 of the low-voltage DC power supply LV. The switching circuit 13 can generate switching signals 16 and 17 for setting the required switching frequency fsw 1 and fsw 2 and send them to the switching frequency setting means 14 and 15 . [0069] The switching frequency fsw 1 /fsw 2 switching circuit 13 receives the step-down/step-up control switching signal 12 supplied from the high-end controller 11 . The switching circuit 13 can thus switch between calculation for generating fsw 1 and another calculation for generating fsw 2 . [0070] If the switching frequency fsw 1 /fsw 2 switching circuit 13 includes an independent calculation circuit for generating fsw 1 and fsw 2 , the absence of the step-down/step-up control switching signal 12 causes no operational problem. If the step-down/step-up control switching signal 12 is input externally, there is no need to provide an independent calculation circuit for generating fsw 1 and fsw 2 in the switching circuit 13 , providing an effect of structuring the switching circuit 13 with less hardware. [0071] According to the second embodiment, the switching frequencies fsw 1 and fsw 2 can be changed during a DC-DC converter operation according to the voltages of the high-voltage DC power supply HV and low-voltage DC power supply LV, thereby enabling a bi-directional DC-DC converter that widens the step-down and step-up ratio ranges to be obtained. Third Embodiment [0072] FIG. 7 shows the entire structure of a bi-directional DC-DC converter according to a third embodiment of the present invention. The functional parts in FIG. 7 that are identical to the corresponding ones in FIG. 1 are assigned the same reference numerals to eliminate duplicate description. FIG. 7 differs from FIG. 1 in that the structure in FIG. 6 is further modified; an operation switching circuit 22 is provided, which receives a control signal 21 from the high-end controller 11 and switches the operation of the DC-DC converter 23 . [0073] The control signal 21 from the high-end controller 11 includes a command for indicating a step-down or step-up operation and frequency setting information about the switching frequency fsw 1 during the step-down operation and the switching frequency fsw 2 during the step-up operation. The operation switching circuit 22 generates a step-down/step-up control switching signal 12 according to the control signal 21 from the high-end controller 11 , and also generates switching signals 16 and 17 to be respectively sent to the switching frequency setting means 14 and 15 . [0074] According to the third embodiment, a bi-directional DC-DC converter can be operated according to a command from a high-end controller 11 . The high-end controller 11 monitors the states of a high-voltage DC power supply HV and low-voltage DC power supply LV and controls an entire system in which the DC-DC converter 23 is mounted, so the high-end controller 11 can command the DC-DC converter to perform an optimum operation according to the state. Fourth Embodiment [0075] FIG. 8 shows the entire structure of a bi-directional DC-DC converter according to a fourth embodiment of the present invention. The functional parts in FIG. 8 that are identical to the corresponding ones in FIG. 1 are assigned the same reference numerals to eliminate duplicate description. FIG. 8 differs from FIG. 1 in that the structure in FIG. 7 is further modified; an operation switching circuit 24 is structured so that it can make a switchover for the DC-DC converter 25 at its discretion, without receiving an external command. Specifically, the operation switching circuit 24 respectively receives voltages 18 and 19 from the high-voltage DC power supply HV and low-voltage DC power supply LV, selects an operation mode in which the DC-DC converter 25 should operate according to the voltage values, and outputs a step-down/step-up control switching signal 12 . The operation switching circuit 24 also generates switching signals 16 and 17 to be respectively sent to the switching frequency setting means 14 and 15 . When, for example, the voltage of the high-voltage DC power supply HV rises to or above a prescribed voltage and the voltage of the low-voltage DC power supply LV falls to or below a prescribed voltage, the operation switching circuit 24 sends a step-down control signal as the step-down/step-up control switching signal 12 , and sends a switching frequency fsw 1 switching signal suitable for the HV and LV voltages. When the HV voltage is equal to or below the prescribed voltage and the LV voltage is equal to or above the prescribed voltage, the operation switching circuit 24 sends a step-up signal as the step-down/step-up control switching signal 12 , and sends a switching frequency fsw 2 switching signal suitable for the HV and LV voltages. [0076] According to the fourth embodiment, the DC-DC converter 25 can perform control by itself according to the values of the voltages of the high-voltage DC power supply HV and low-voltage DC power supply LV, even when there is no signal from a high-end system. Fifth Embodiment [0077] FIG. 9 shows the entire structure of a bi-directional DC-DC converter according to a fifth embodiment of the present invention. The functional parts in FIG. 9 that are identical to the corresponding ones in FIG. 1 are assigned the same reference numerals to eliminate duplicate description. FIG. 9 differs from FIG. 1 in that the structure in FIG. 6 is further modified; the bi-directional DC-DC converter further comprises a battery controller 26 for monitoring and controlling the state of the battery in the high-voltage DC power supply HV and a battery controller 27 for monitoring and controlling the state of the battery in the low-voltage DC power supply LV. A signal line 29 , which includes information about the HV voltage and current and the like, connects the high-voltage DC power supply HV to the battery controller 26 . An operation selecting circuit 28 receives a state signal 31 concerning the HV from the battery controller 26 . Similarly, a signal line 30 connects the LV to the battery controller 27 , and the battery controller 27 inputs a state signal 32 concerning the LV into the operation selecting circuit 28 . The operation selecting circuit 28 thus switches between step-down control and step-up control of the bi-directional DC-DC converter 33 , according to the states of the batteries of the high-voltage DC power supply HV and low-voltage DC power supply LV respectively sent from the battery controllers 26 and 27 . That is, the operation selecting circuit 28 receives the HV state signal 31 from the battery controller 26 and the LV state signal 32 from the batter controller 27 , and outputs the step-down/step-up control signal 12 , fsw 1 switching signal 16 , and fsw 2 switching signal 17 . [0078] According to the fifth embodiment, the battery controllers 26 and 27 , which monitor the states of the HV and LV batteries, enables precise switching between step-down control and step-up control and precise setting of the switching frequencies fsw 1 and fsw 2 . Since signals can be received from battery controllers specific to battery state monitoring, processing for battery state confirmation does not need to be performed in the operation selecting circuit 28 , providing an effect of reducing the size of the operation selecting circuit 28 . Sixth Embodiment [0079] FIG. 10 shows the entire structure of a bi-directional DC-DC converter according to a sixth embodiment of the present invention. The functional parts in FIG. 10 that are identical to the corresponding ones in FIG. 1 are assigned the same reference numerals to eliminate duplicate description. FIG. 10 differs from FIG. 9 in that a switching frequency switching means 34 is provided as a modified part. Other parts not shown are structured as shown in FIG. 9 . The switching means 34 outputs a clock frequency switching signal 35 used to set frequencies for control signals generated by the step-down control circuit 4 and step-up control circuit 5 . A clock frequency switching signal 36 is used to set the frequency of the clock signal 35 . Reference numeral 37 indicates a bi-directional DC-DC converter. The step-down/step-up control switching signal 12 and clock frequency switching signal 36 are generated as illustrated in FIGS. 6 to 9 . [0080] During the step-down operation, the step-down/step-up control switching signal 12 commands a voltage drop, so the frequency switching means 34 outputs a clock signal 35 for the step-down operation. The step-down control circuit 4 receives the clock signal 35 and outputs a control signal for the step-down operation. The control signal is supplied to the main high-voltage circuit 1 and main low-voltage circuit 2 through the selectors 8 and 9 . In this case, the selectors 8 and 9 select a signal from the step-down control circuit 4 according to the step-down/step-up control switching signal 12 , and output it. The clock signal 35 for step-down control is also supplied to the step-up control circuit 5 , so the step-up control circuit 5 also outputs to the selectors a signal at the same frequency as the signal in the step-down control circuit 4 . However, the selectors 8 and 9 have selected the signals from the step-down control circuit 4 , causing no problem. It is also possible to use the step-down/step-up control switching signal 12 or the like to control the step-up control circuit 5 so that it does not operate. [0081] During the step-up operation, the step-down/step-up control switching signal 12 commands voltage boosting, so the frequency switching means 34 outputs a clock signal 35 for the step-up operation. The step-up control circuit 5 receives the clock signal 35 and outputs a control signal for the step-up operation. The control signal is supplied to the main high-voltage circuit 1 and main low-voltage circuit 2 through the selectors 8 and 9 . In this case, the selectors 8 and 9 select a signal from the step-up control circuit 5 according to the step-down/step-up control switching signal 12 and output it. The clock signal 35 for step-up control is also supplied to the step-down control circuit 4 , but no problem occurs as in the step-down operation. In the step-up operation as well, it is also possible to use the step-down/step-up control switching signal 12 or the like to control the step-down control circuit 4 so that it does not operate. [0082] The frequency switching means 34 shown in FIG. 10 can function during both the step-down operation and step-up operation in a single circuit block, according to the step-down/step-up control switching signal 12 and clock signal 36 . This idea can also be applied to the embodiments in FIGS. 6 to 9 . [0083] According to the sixth embodiment, there is no need to provide the frequency switching means 34 for each of the step-down and step-up operations, so a switching frequency for step-down control and a switching frequency for step-up control can be set separately with less circuit devices. Seventh Embodiment [0084] FIG. 11 shows the entire structure of a bi-directional DC-DC converter according to a seventh embodiment of the present invention. The functional parts in FIG. 11 that are identical to the corresponding ones in FIG. 10 are assigned the same reference numerals to eliminate duplicate description. Only differences from FIG. 10 will be described. In FIG. 11 , reference numerals 38 and 39 each indicate an OR circuit; reference numeral 40 indicates a step-down control circuit with an enable terminal; reference numeral 41 indicates a step-up control circuit with an enable terminal; reference numeral 42 indicates a bi-directional DC-DC converter. [0085] In the seventh embodiment as well, the step-down/step-up control switching signal 12 and clock frequency switching signals 16 and 17 are generated as illustrated in FIGS. 6 to 9 , so they are not shown. [0086] During a step-down operation, the step-down/step-up control switching signal 12 commands a voltage drop, so the step-down control circuit 40 operates and the step-up control circuit 41 does not operate. The step-up control circuit 41 is controlled so that when it is not operational, its output signal is low. The OR circuits 38 and 39 each OR the outputs of the step-down control circuit 40 and step-up control circuit 41 and send the resulting signal. Since the output of the step-up control circuit 41 is low, the output of the step-down control circuit 40 is sent to the main high-voltage circuit 1 and main low-voltage circuit 2 . At this time, the switching frequency setting means 14 and 15 respectively supply a clock signal to the step-down control circuit 40 and step-up control circuit 41 , according to the switching signals 16 and 17 . [0087] During a step-up operation, the step-down/step-up control switching signal 12 commands voltage boosting, so the step-down control circuit 40 does not operate and the step-up control circuit 41 operates. The step-down control circuit 40 is controlled so that when it is not operational, its output signal is low. The OR circuits 38 and 39 each OR the outputs of the step-down control circuit 40 and step-up control circuit 41 and send the resulting signal. Since the output of the step-down control circuit 40 is low, the output of the step-up control circuit 41 is sent to the main high-voltage circuit 1 and main low-voltage circuit 2 . At this time, the switching frequency setting means 14 and 15 respectively supply a clock signal to the step-down control circuit 40 and step-up control circuit 41 , according to the switching signals 16 and 17 . [0088] According to the seventh embodiment, Enable signals are input to the step-down control circuit 40 and step-up control circuit 41 so that they do not operate actively when they do not need to operate, providing an effect of reducing the power consumption of the control circuits. Of course, it is also possible to reduce the power consumption of the switching frequency setting means 14 and 15 by supplying Enable signals to them so that they stop when they do not need to operate. Furthermore, in the above structure, a circuit for selecting a signal from the step-down control circuit 40 and a signal from the step-up control circuit 41 can be implemented as a simple OR circuit. Eighth Embodiment [0089] FIG. 12 shows the entire structure of a bi-directional DC-DC converter according to an eighth embodiment of the present invention. The functional parts in FIG. 12 that are identical to the corresponding ones in FIG. 1 are assigned the same reference numerals to eliminate duplicate description. FIG. 12 shows examples of the internal structures of the main high-voltage circuit 1 and main low-voltage circuit 2 in FIG. 1 . [0090] First, the structure of the main high-voltage circuit 1 will be described. Connected to the high-voltage DC power supply HV are a smoothing capacitor 43 , a pair of switching devices 44 and 45 connected in series, and another pair of switching devices 46 and 47 connected in series. Freewheel diodes 48 to 51 are respectively connected to the switching devices 44 to 47 in parallel. When the switching devices 44 to 47 are metal-oxide semiconductor field effect transistors (MOSFETs), body diodes can be used. [0091] During the step-down operation, when the switching devices 44 to 47 are operated, a DC voltage is converted into an AC voltage and the AC voltage is generated on the primary winding 53 of the transformer 3 through an auxiliary reactor 52 . When the polarity of the current flowing in the primary winding 53 of the transformer 3 is inverted, the auxiliary reactor 52 adjusts the current gradient. The auxiliary reactor 52 may be replaced with a leak inductance of the transformer 3 ; in this case, the auxiliary reactor 52 can be eliminated. [0092] During the step-up operation, the AC voltage generated on the primary winding 53 of the transformer 3 is rectified and converted by diodes 48 to 51 into a DC voltage. The switching devices 44 to 47 may be kept turned on while forward current flows from the anode to the cathode in each of the diodes 48 to 51 , that is, so-called synchronous rectification may be performed. [0093] Next, the structure of the main low-voltage circuit 2 will be described. In the example in FIG. 12 , a current-doubler synchronous rectifier is used as the main low-voltage circuit. The current-doubler synchronous rectifier is well-known, as disclosed in, for example, Japanese Patent Laid-open No. 2003-199339. Connected in parallel to the low-voltage DC power supply LV are a smoothing capacitor 61 , a pair of a reactor 59 and switching device 56 connected in series, and another pair of a reactor 60 and switching device 55 connected in series; the smoothing capacitor 61 and the reactor 60 and switching device 55 pairs are connected in parallel. Freewheel diodes 58 and 57 are respectively connected to the switching devices 56 and 55 in parallel. When the switching devices 56 and 55 are MOSFETs, body diodes can be used. [0094] During the step-down operation, the main low-voltage circuit 2 configured as the current-doubler circuit rectifies the AC voltage generated on the transformer 3 by using the diodes 57 and 58 . The reactors 59 and 60 and the capacitor 61 smooth the rectified voltage to obtain a DC voltage LV. The switching devices 55 and 56 may be kept turned on while forward current flows from the anode to the cathode in each of the diodes 57 and 58 , that is, so-called synchronous rectification may be performed. [0095] During the step-up operation, the switching devices 55 and 56 are turned on alternately to convert the DC voltage LV to an AC voltage and generate the AC voltage on the secondary winding 54 of the transformer 3 . The generated AC voltage is converted according to the turns ratio of the transformer 3 , and then rectified into a DC voltage by the main high-voltage circuit 1 , resulting in a high DC voltage. [0096] In the example in the eighth embodiment, MOSFETs are used as the switching devices, but switching devices such as insulated gate bipolar transistors (IGBTs) may be used without problems. [0097] FIG. 13 shows an example of timing charts when the step-down operation is performed in FIG. 12 . The gate signals of the switching devices 44 to 47 , 55 , and 56 are indicated by A to F. [0098] The gate signals A and B have a period during which they are kept low concurrently so that both switching devices 44 and 45 are not turned on concurrently. Similarly, the gate signals C and D have a period during which they are kept low concurrently so that both switching devices 46 and 47 are not turned on concurrently. In this case, A and C are controlled in such a way that they are shifted from each other. While both A and D are on and both B and C are on, a voltage is generated on the primary winding of the transformer 3 and electric power is supplied to the low-voltage side through the transformer 3 . The switching devices 55 and 56 on the low-voltage side perform synchronous rectification according to the control signals E and F shown in FIG. 13 so that the AC voltage generated on the secondary winding of the transformer 3 is rectified. The switching frequency at that time is 1/T 1 . The switching frequency setting means 6 enables a switching frequency suitable for the step-down operation to be set without being affected by the step-up operation. [0099] FIG. 14 shows examples of timing charts when the step-up operation is performed in FIG. 12 . In this example, the AC voltage generated on the primary winding of the transformer 3 is rectified by the diodes 48 to 51 with A to D turned off. The control signals E and F used to control the switching devices 55 and 56 on the low-voltage side are switched alternately as shown in FIG. 14 so as to generate an AC voltage on the secondary winding 54 of the transformer 3 and supply electric power to the high-voltage side. The switching frequency at that time is 1/T 2 . The switching frequency setting means 7 enables a switching frequency suitable for the step-up operation to be set without being affected by the step-down operation. Ninth Embodiment [0100] FIG. 15 shows the entire structure of a bi-directional DC-DC converter according to a ninth embodiment of the present invention. The functional parts in FIG. 15 that are identical to the corresponding ones in FIG. 12 are assigned the same reference numerals to eliminate duplicate description. FIG. 15 differs from FIG. 12 in that the secondary winding of the transformer 62 has a center tap, at which the winding is divided into segments 63 and 64 . Accordingly, the main low-voltage circuit is changed to a structure indicated by reference numeral 70 . The main low-voltage circuit 70 comprises a reactor 65 , switching devices 66 and 67 , and diodes 68 and 69 connected in parallel to these switching devices. When the switching devices 66 and 67 are metal-oxide MOSFETs, body diodes can be used as the diodes 68 and 69 . [0101] The operation of the main circuit 70 having a center tap is well known through, for example, documents, so its detailed description will be omitted. Timing charts for controlling the embodiment in FIG. 15 indicate operations similar to those in FIGS. 13 and 14 . [0102] Although exemplary circuits that practice embodiments 8 and 9 of the present invention were shown in FIGS. 12 and 15 in detail, it would be appreciated that the main high-voltage circuit and main low-voltage circuit are not limited to the circuits shown in these drawings, but any circuits that can operate as both an inverter and a rectifier can be used. Tenth Embodiment [0103] FIG. 16 shows the entire structure of a bi-directional DC-DC converter according to a tenth embodiment of the present invention. The functional parts in FIG. 16 that are identical to the corresponding ones in FIG. 12 are assigned the same reference numerals to eliminate duplicate description. The bi-directional DC-DC converter 78 in the tenth embodiment is structured so that the transformer turns ratios are changed by switches 76 and 77 between the step-down operation and the step-up operation. The primary winding of the transformer 72 is divided into segments 73 and 74 . The secondary winding is indicated by reference numeral 75 . [0104] During the step-down operation, the switch 76 is turned on and the switch 77 is turned off so that only the segment 73 of the primary winding is used to reduce the turns ratio (N 1 ) of the transformer 72 . During the step-up operation, the switch 76 is turned off and the switch 77 is turned on so that the segments 73 and 74 of the primary winding are connected in series to increase the turns ratio (N 2 ) of the transformer 72 . Since the turns ratio of the transformer 72 is changed between the step-down operation and the step-up operation as described above, the step-down ratio and step-up ratio can be set to values optimal to the respective operations. In the tenth embodiment, the step-down control circuit 4 and step-up control circuit 5 are operated according to signals generated by the switching frequency setting means 6 , so the switching frequencies during the step-down operation and the step-up operation are the same. Therefore, the transformer 72 is used to make a switchover between the step-down ratio and the step-up ratio. The operations in the tenth embodiment are the same as in the embodiment shown in FIG. 1 except that the turns ratios of the primary transformer are changed. [0105] According to the tenth embodiment, the step-down ratio and step-up ratio can be changed to desired value by operating switches such as relays. When the converter is mounted on a vehicle, relays and other switches may cause incorrect contacts due to vibration, bi-directional DC-DC converters as described so far are considered to be more preferable. [0106] It would be understood that with a switching frequency setting means for the step-down control circuit 4 and another switching frequency setting means for the step-up control circuit 5 provided independently as shown in FIG. 1 , a means for setting switching frequencies optimal for the step-down operation and step-up operation can be provided together. Eleventh Embodiment [0107] FIG. 17 shows the entire structure of a bi-directional DC-DC converter according to an eleventh embodiment of the present invention. The functional parts in FIG. 17 that are identical to the corresponding ones in FIG. 16 are assigned the same reference numerals to eliminate duplicate description. The bi-directional DC-DC converter 85 in the eleventh embodiment is also structured so that the transformer turns ratios are switched between the step-down operation and the step-up operation. FIG. 17 differs from FIG. 16 in that the turns ratios are switched by switches 83 and 84 between the step-down operation and the step-up operation on the secondary winding side of the transformer 79 . The primary winding 80 of the transformer 79 is divided into segments 81 and 82 . Reference numeral 83 and 84 indicates switches, and reference numeral 85 indicates a bi-directional DC-DC converter. [0108] During the step-down operation, the switch 83 is turned off and the switch 84 is turned on so that the segments 81 and 82 of the secondary winding are connected in series to decrease the turns ratio (N 1 ). During the step-up operation, the switch 83 is turned on and the switch 84 is turned off so that only the segment 81 of the secondary winding is used to increase the turns ratio (N 2 ) of the transformer 79 . This type of operation provides an effect similar to that in the tenth embodiment shown in FIG. 16 . Twelfth Embodiment [0109] FIG. 18 shows the entire structure of a bi-directional DC-DC converter according to a twelfth embodiment of the present invention. The functional parts in FIG. 18 that are identical to the corresponding ones in FIG. 12 are assigned the same reference numerals to eliminate duplicate description. In the twelfth embodiment, the structure of the main circuit in FIG. 12 is used as the base, and the taps of the transformer are selectively used to switch reactor values and transformer turns ratios between the step-down operation and the step-up operation. During the step-down operation, the switch 136 is turned off and the switch 137 is turned on so that the auxiliary reactor 135 and primary winding 132 are operated effectively. During the step-up operation, the switch 136 is turned on and the switch 137 is turned off so that the auxiliary reactor 134 and the primary windings 131 and 132 are operated effectively. Accordingly, the auxiliary reactor value during the step-up operation is made small and the transformer turns ratios are made large, relative to the step-down operation. The reason why a small auxiliary reactor value is set during the step-up operation is that due to a voltage drop caused by the auxiliary reactor, the voltages generated on the primary windings 131 and 132 are not supplied effectively to the high-voltage DC power supply HV. Thirteenth Embodiment [0110] FIG. 19 shows the entire structure of a bi-directional DC-DC converter according to a thirteenth embodiment of the present invention. The functional parts in FIG. 19 that are identical to the corresponding ones in the previous drawings are assigned the same reference numerals to eliminate duplicate description. The bi-directional DC-DC converter in the thirteenth embodiment is an example of a non-insulated bi-directional DC-DC converter that does not use a transformer for electric power conversion. Reference numeral 86 indicates a smoothing capacitor on the high-voltage side, reference numerals 87 and 88 indicate switching devices, and reference numerals 89 and 90 indicate diodes. When the switching devices 87 and 88 are MOSFETs, body diodes can be used as the diodes 89 and 90 . Reference numeral 91 indicates a reactor, and reference numeral 92 indicates a smoothing capacitor on the low-voltage side. [0111] When the switching device 87 is operated during the step-down operation, electric power is sent from the HV side to the LV side. Specifically, when the switching device 87 is turned off, the current flowing in the reactor 91 causes the diode 90 to supply a forward current. At that time, the switch 88 can be turned on to perform synchronous rectification. [0112] When the switching device 88 is operated during the step-up operation, electric power is sent from the LV side to the HV side. Specifically, when the switching device 88 is turned off, the current flowing in the reactor 91 causes the diode 89 to supply a forward current. At that time, the switch 87 can be turned on to perform synchronous rectification. The bi-directional DC-DC converter is indicated by reference numerals 93 . [0113] FIG. 20 shows examples of timing charts when the bi-directional DC-DC converter according to the thirteenth embodiment of the present invention in FIG. 19 performs the step-down operation and step-up operation, assuming that synchronous rectification is performed. The switching frequency cycle during the step-down operation, given as T 1 , and the switching frequency cycle during the step-up operation, given as T 2 , can be controlled independently. [0114] According to the thirteenth embodiment, if the switching frequency during the step-down operation and the switching frequency during the step-up operation are controlled independently, it is possible in the non-insulated converter as well to set the step-down ratio and step-up ratio in a wide range. Fourteenth Embodiment [0115] FIG. 21 shows, as a fourteenth embodiment of the present invention, a system structure in which a bi-directional DC-DC converter is applied to a vehicle-mounted hybrid system. Reference numeral 100 indicates an engine; reference numeral 101 indicates a motor/generator for powering and regeneration, which operates as the inverter during powering and operates as the generator during regeneration; reference numerals 102 indicates an inverter/converter, which operates as the inverter during powering and rotates a motor by using electric power of the high-voltage DC power supply HV, and operates as the converter during regeneration and converts the AC voltage generated by the generator and charges the high-voltage DC power supply HV. [0116] The bi-directional DC-DC converter 103 is disposed between the HV and the LV and performs bi-directional power conversion. An electronic unit 104 is mounted on the vehicle. Battery controllers 105 and 106 respectively control the power of the HV and LV. An electronic control unit ECU 106 functions as a high-end unit that controls the bi-directional DC-DC converter 103 . Specifically, the ECU 106 switches the bi-directional DC-DC converter 103 between the step-down operation and the step-up operation, sends setting information about the switching frequency to the DC-DC converter 103 , and receives the operation state and other information from the DC-DC converter 103 . The battery controllers 105 and 106 and electronic control unit ECU 106 mutually communicate through a network 108 to transmit and receive information. [0117] The DC-DC converter 103 in the fourteenth embodiment communicates directly with the electronic control unit ECU 106 . However, the DC-DC converter 103 may also use the network 108 to communicate with the electronic control unit ECU 106 and battery controllers 105 and 106 . [0118] In the fourteenth embodiment, it is assumed that, during the step-down operation, the DC-DC converter 103 functions to supply electric power to the vehicle-mounted electronic unit connected to the LV power supply and that, during the step-up operation, it functions as an emergency unit to start the engine when the voltage of the HV is lowered. However, the present invention is not limited to these applications but can be used to convert electric power between DC voltages. The high-voltage DC power supply and low-voltage power DC power supply described above are assumed to comprise a secondary battery, a capacitor, and other parts. [0119] The above embodiments of the present invention are effective in bi-directionally converting electric power between a high-voltage DC power supply and a low-voltage DC power supply in a vehicle-mounted system when there is a large difference in voltage between the power supplies and their voltages largely vary during an operation. INDUSTRIAL APPLICABILITY [0120] The above embodiments have been mainly described about vehicle-mounted applications, but the present invention can also be applied to other applications in which, for example, DC-DC power conversion is necessary in a battery charging/discharging system.

The inventive bi-directional DC-DC converter addresses a problem of an insufficient step-up ratio during the step-up operation that is caused when a turns ratio of the transformer is determined to, for example, match the step-up operation and also address a contrary problem of an insufficient step-down ratio during the step-down operation that is caused when a turns ratio is determined to match the step-up operation. In the inventive bi-directional DC-DC converter that uses a transformer for both step-down and step-up operations, a switching frequency for operating a switching device is set separately for the step-down and step-up operations. For example, when the switching frequency during the step-up operation is lower than the switching frequency during the step-down operation, the range in which the duty ratio in PWM control can be controlled is widened, compensating for step-up ratio insufficiency. Conversely, step-down ratio insufficiency is compensated for by making the switching frequency during the step-down operation lower than the switching frequency during the step-up operation.

TECHNICAL FIELD [0001] This application claims benefit from prior Provisional application Ser. No. 60/135,290, filed May 21, 1999. [0002] This invention relates to an apparatus and method for the construction and utilization of molecular deposition domains. More specifically, this invention is a method for the construction and utilization of molecular deposition domains into a high density molecular array for identifying and characterizing molecular interaction events. BACKGROUND [0003] Interactions between molecules is a central theme in living systems. These interactions are key to myriad biochemical and signal transduction pathways. Messages from outside a cell travel along signal transduction pathways into the cell's nucleus, where they trigger key cellular functions. Such pathways in turn dictate the status of the overall system. Slight changes or abnormalities in the interactions between biomolecules can effect the biochemical and signal transduction pathways, resulting in inappropriate development, cancer, a variety of disease states, and even cell senescence and death. On the other hand, it can be extremely beneficial to develop reagents and effectors that can inhibit, stimulate, or otherwise effect specific types of molecular interactions in biochemical systems; including biochemical and signal transduction pathways. Reagents and effectors that effect nucleus interactions may often become very powerful drugs which can be used to treat a variety of conditions. [0004] Current Technology [0005] Several recent studies have shown that a scanning probe microscope “SPM” may be used to study molecular interactions by making a number of measurements. The SPM measurements may include changes in height, friction, phase, frequency, amplitude, and elasticity. The SPM probe can even perform direct measurements of the forces present between molecules situated on the SPM probe and molecules immobilized on a surface. For example, see Lee, G.U., L.A. Chrisey, and R.J. Colton, Direct Measurement of the Forces Between Complementary Strands of DNA. Science, 1994. 266: p. 771-773; Hinterdorfer, P., W. Baumgartner, H.J. Gruber, and H. Schindler, Detection and Localization of Individual Antibody-antigen Recognition Events by Atomic Force Microscopy, Proc. Natl. Acad. Sci., 1996. 93: p. 3477-3481; Dammer, U., 0 . Popescu, P. Wagner, D. Anselmetti, H.J. Guntherodt, and G.N. Misevic, Binding Strength Between Cell Adhesion Poteoglycans Measured by Atomic Force Microscopy. Science, 1995. 267: p. 1173-1175; Jones, v. et al. Microminiaturized Immunoassays Using Atomic Force Microscopy and Compositionally Patterned Antigen Arrays, Analy. Chem., 1998 70(7): p. 12331241; and Rief, M., F. Oesterhelt, B. Heymann, and H.E. Gaub, Single Molecule Force Spectroscopy on Polysaccharides by Atomic Force Microscopy, Science, 1997. 275: p. 1295-1297. The above studies illustrate that it is possible to readily and directly measure the interaction between and within virtually all types of molecules by utilizing an SPM. Furthermore, recent studies have shown that it is possible to use direct force measurement to detect changes in molecular complex formation caused by the addition of a soluble molecular species. A direct force measurement may elucidate the effect of soluble molecular species on the interaction between a molecular species on an SPM probe and a surface. [0006] Molecular Arrays [0007] The ability to measure molecular events in patterned arrays is an emerging technology. The deposition material can be deposited on a solitary spot or in a variety of sizes and patterns on the surface. The arrays can be used to discover new compounds which may interact in a characterizable way with the deposited material. Arrays provide a large number of different test sites in a relatively small area. To form an array, one must be able to define a particular site at which a deposition sample can be placed in a defined and reproducible manner. [0008] There are four approaches for building conventional molecular arrays known in the art. These prior art methods include 1) mechanical deposition, 2) in situ photochemical synthesis, 3) “ink jet” printing, and 4) electronically driven deposition. The size of the deposition spot (or “domain”) is of particular importance when utilizing an SPM to scan for molecular recognition events. Current SPM technology only allows a scan in a defined area. Placing more domains in this defined area allows for a wider variety of molecular interaction events to be simultaneously tested. [0009] Mechanical deposition is commonly carried out using a “pin tool” device. Typically the pin tool is a metal or similar cylindrical shaft that may be split at the end to facilitate capillary take up of liquid. Typically the pin is dipped in the source and moved to the deposition location and touched to the surface to transfer material to that domain. In one design the pin tool is loaded by passing through a circular ring that contains a film of the desired sample held in the ring by surface tension. The pin tool is washed and this process repeated. Currently, pin tool approaches are limited to spot sizes of 25 to 100 microns or larger. The spot size puts a constraint on the maximum density for the molecular deposition sites constructed in this manner. A need exists for a method that allows for molecular domains of smaller dimensions to be deposited. [0010] In situ photochemical procedures allow for the construction of arrays of molecular species at spatial addresses in the 1-10 micron size range and larger. In situ photochemical construction can be carried out by shining a light through a mask. Photochemical synthesis occurs only at those locations receiving the light. By changing the mask at each step, a variety of chemical reactions at specific addresses can be carried out. The photochemical approach is usually used for the synthesis of a nucleic acid or a peptide array. A significant limitation of this approach is that the size of the synthetic products is constrained by the coupling efficiency at each step. Practically, this results in appreciable synthesis of only a relatively short peptide and nucleic acid specimen. In addition, it becomes increasingly improbable that a molecule will fold into a biologically relevant higher order architecture as the synthetic species becomes larger. A need exists for an alternative method for deposition of macromolecular species that will preserve the molecular formation of interest in addition to avoiding the cost of constructing the multiple masks used in this method. [0011] Ink jet printing is an alternative method for constructing a molecular array. Ink jet printing of molecular species produces spots in the 100 micron range. This approach is only useful for printing a relatively small number of species because of the need for extensive cleaning between printing events. A key issue with ink jet printing is maintenance of the structural/functional integrity of the sample being printed. The ejection rate of the material from the printer results in shear forces that may significantly compromise sample integrity. A need exists for a method that will retain the initial structure and functional aspects of the deposition material and that will form smaller spots than are possible with the above ink jet method. [0012] Electronic deposition is yet another method known for the construction of molecular arrays. Electronic deposition may be accomplished by the independent charging of conductive pads, causing local electrochemical events which lead to the sample deposition. This approach has been used for deposition of DNA samples by drawing the DNA to specific addresses and holding them in a capture matrix above the address. The electronic nature of the address can be used to manipulate samples at that location, for example, to locally denature DNA samples. A disadvantage of this approach is that the address density and size is limited by the dimensions of the electronic array. [0013] A need exists for a molecular deposition technique that will allow for smaller deposition spots (domains). Smaller deposition domains allow for an array to be constructed with a greater density of domains. More domains further allow for a wider variety in the deposition material to be placed on the same array, allowing a user to search for more molecular interaction events simultaneously. [0014] A further need exists for the ability to place these spots at a defined spatial address. Placing the domains at defined spatial addresses allows the user to know exactly what deposition material the SPM is scanning at any given time. [0015] Furthermore, a need exists for a method to make deposition domains with large molecular weight samples that also retains the desired chemical formation. Finally, a need exists for the efficient construction of these molecule domains into an array. [0016] Molecular Detection [0017] All of the above examples are further limited because they require some type of labeling of the deposition sample for testing. Typical labeling schemes may include fluorescent or other tags coupled to a probe molecule. In a typical molecular event experiment, an array of known samples, for example DNA sequences, will be incubated with a solution containing a fluorescent indicator. In the DNA example this would be fluorescently or otherwise labeled nucleic acids, most often a single stranded DNA of an unknown sequence. Specific sequence elements are identified in the DNA sample by virtue of the hybridization of the label to addresses containing known sequence elements. This process has been used to screen entire ensembles of expressed genes in a given population of cells at a particular time or under a particular set of conditions. Other labeling procedures have also been employed, including RF (radio frequency) labels and magnetic labels. These methods are less frequently used, however, than the fluorescent label methods desired above. All of these labels hinder experiments with extra steps, reagents, and in some cases, risk. [0018] Other methods for the detection of the interactions of molecules on a molecular array include inverse cyclic voltametry, capacitance or other electronic changes, radioactivity (such as with isotopes of phosphorous), and chemical reactions. In virtually all cases, some form of labeling of the probe molecule that is added to the array is required. This is a significant limitation of current arrays. A need exists for a method that does not require this extra labeling step. [0019] Scanning Probe Microscopy [0020] A wide variety of SPM instruments are capable of detecting optical, electronic, conductive, and other properties. One form of SPM, the atomic force microscope (AFM), is an ultra-sensitive force transduction system. In the AFM, a sharp tip is situated at the end of a flexible cantilever and scanned over a sample surface. While scanning, the cantilever is deflected by the net sum of the attractive and repulsive forces between the tip and sample. If the spring constant of the cantilever is known, the net interaction force can be accurately determined from the deflection of the cantilever. The deflection of the cantilever is usually measured by the reflection of a focused laser beam from the back of the cantilever onto a split photodiode, constituting an “optical lever” or “beam deflection” mechanism. Other methods for the detection of cantilever deflection include interferometry and piezoelectric strain gauges. [0021] The first AFMs recorded only the vertical displacements of the cantilever. More recent methods involve resonating the tip and allowing only transient contact, or in some cases no contact at all, between it and the sample. Plots of tip displacement or resonance changes as it traverses a sample surface are used to generate topographic images. Such images have revealed the three dimensional structure of a wide variety of sample types including material, chemical, and biological specimens. Some examples of the latter include DNA, proteins, chromatin, chromosomes, ion channels, and even living cells. [0022] In addition to its imaging capabilities, the AFM can make extremely fine force measurements. The AFM can directly sense and measure forces in the microNetwon ( 10 −6 ) to picoNewton ( 10 −12 ) range. Thus, the AFM can make extremely fine force within single molecules. Moreover, the AFM can measure a wide variety of other forces and phenomena, such as magnetic fields, thermal gradients and viscoelasticity. This ability can be exploited to map force fields on a sample surface, and reveal with high resolution the location and magnitude of these fields, as in, for example, localizing complexes of interest located on a specific surface. [0023] Direct Force Measurement [0024] To make molecular force measurements, the AFM probe is functionalized with a molecule of interest. This bio- or chemi-active probe is then scanned across the surface of interest. The molecule tethered to the probe interacts with the corresponding molecule or atoms of interest on the surface being studied. The interactions between the molecule functionalized on the probe and the molecules or atoms on the surface create minute forces that can be measured by displacement of the probe. The measurement is typically displayed as a force vs. distance curve (“force curve”). [0025] To generate a force curve, the tip or sample is cycled through motions of vertical extension and retraction. Each cycle brings the tip into contact with the sample, then pulls the tip out of contact. The displacement of the cantilever is zero until the extension motion brings the tip into contact with the surface. Then the tip and sample are physically coupled as the extension continues. The physical coupling is the result of hard surface contact (Van der Waals interactions) between the probe and the surface. This interaction continues for the duration of the extension component of the cycle. When the cycle is reversed and the tip retracted, the physical contact is broken. If there is no attractive interaction between the tip and sample the tip separates from the sample at the same position in space at which they made contact during extension. However, if there is an adhesive interaction between the tip and sample during retraction, the cantilever will bend past its resting position and continue to bend until the restoring force of the cantilever is sufficient to rupture the adhesive force. [0026] In the case of extendable molecular interactions, the distance between the tip and surface at which a rupture is observed corresponds to the extension length of the molecular complex. This information can be used to measure molecular lengths and to measure internal rupture forces within single molecules. In a force curve an adhesive interaction is represented by an “adhesion spike.” Since the spring constant of the probe is known, the adhesive force (the unbinding force) can be precisely determined. Upon careful inspection of a typical adhesion spike, many small quantal unbinding events are frequently seen. The smallest unbinding event that can be evenly divided into the larger events can be interpreted as representing the unbinding force for a single molecular pair. [0027] The spectra produced by these binding events will contain information about the coupling contacts holding the molecules together. Thus, it is possible to interpret the signature generated by a mechanical denaturation experiment with regard to the internal structure of the molecule. An SPM can further utilize height, friction, and elasticity measurements to detect molecular recognition events. Molecular recognition events are when one molecule interacts with another molecule or atom in, for example, an ionic bond, a hydrophobic bond, electrostatic bond, a bridge through a third molecule such as water, or a combination of these methods. [0028] In an alternative approach, the AFM probe is oscillated at or near its resonance frequency to enable the measurement of recognizance parameters, including amplitude, frequency and phase. Changes in the amplitude, phase, and frequency parameters are extremely sensitive to variations in the interaction between the probe and the surface. If the local elasticity or viscosity of the surface changes as a result of a molecular recognition event, there is a shift in one or more of these parameters. [0029] Others have reported using AFMs and STMs for the deposition of materials. One report is from Chad Mirkin (Northwestern University) in which he used an AFM to write nanometer scale molecule features with short alkane chains. Hong, S., J. Zhu, and C. A. Mirkin, Multiple Ink Nanolithography: Toward A Multiple-Pen Nano-Plotter, Science. 1999, p. 523-525. A need exists, however, for a molecular domain deposition method that is not limited to short chain length molecules. A need exists for a method for depositing longer chain length macromolecules that does not change or hinder the formation of the deposited molecule. [0030] A need exists for an improved apparatus and method for utilization in the detection of molecular interaction events. A need exists for a method for the creation of small, sub-micron scale molecular domains at defined spatial addresses. This apparatus should enable the user to test for a variety of different types of events in a spatially and materially efficient manner by facilitating the deposition, exposure, and scanning of molecular domains to detect a resultant molecular interaction event. Furthermore, an apparatus is needed that enables the placement of a large number of molecular domains in a relatively small area. BRIEF DESCRIPTION OF THE DRAWINGS [0031] [0031]FIG. 1 is a block diagram of the method of forming a deposition domain. [0032] [0032]FIG. 2 is a block diagram of the method of forming an array and utilizing the same. [0033] [0033]FIG. 3 is a side view of the deposition device used with the present invention. [0034] [0034]FIG. 4 is a side view of the deposition device and the microspheres of the present invention. [0035] [0035]FIG. 5 is a side view of a microsphere attached to a deposition device. [0036] [0036]FIG. 6 is an alternative attachment of the microsphere to the deposition device. [0037] [0037]FIG. 7 a is a side view of the deposition device before loading the deposition material on it. [0038] [0038]FIG. 7 b is a side view of a capillary bridge between the deposition material and the microsphere during loading of the deposition material [0039] [0039]FIG. 8 a is a side view of a microsphere with deposition material loaded on the microsphere. [0040] [0040]FIG. 8 b is a side view of a capillary bridge between the microsphere and a surface during the deposition of a deposition domain. [0041] [0041]FIG. 9 is a side view of a deposition domain on an array just after the microsphere has been withdrawn. [0042] [0042]FIG. 10 is a perspective view of an array of the present invention. [0043] [0043]FIG. 11 is an outline view of an example scan of an array after exposure to a target medium. SUMMARY [0044] A method for the construction of a molecular deposition domain on a surface, comprising, providing a surface, depositing a deposition material on a deposition device, and depositing the deposition material on the surface using said deposition device, forming a molecular deposition domain smaller than one micron in total area. [0045] Another embodiment comprises method for constructing an array of molecular deposition domains including the steps of providing a surface, providing an at least one deposition material, depositing a first deposition material on a deposition device, depositing the first deposition material on the surface in a known position, forming a first molecular deposition domain smaller than one micron in total area, cleaning the deposition device, and repeating the above steps with an at least one other deposition material, creating an array of two or more deposition domains on said surface. [0046] Yet another embodiment comprises a method for detecting a target sample, the method comprising, forming a molecular array on a surface, the molecular array including an at least one molecular deposition domain, said at least one molecular deposition domain smaller than one micron in total area, exposing the surface to a sample medium, the sample medium containing one or more target samples which cause a molecular interaction event in one or more of the at least one deposition domain, and scanning the surface using a scanning probe microscope to detect the occurrence of the molecular interaction event caused by the target sample. [0047] A still further embodiment comprises a molecular array for characterizing molecular interaction events, comprising a surface, and an at least one molecular deposition domain deposited on said surface wherein the spatial address of the domain is less than one micron in area. [0048] Another embodiment comprises a method for the processing of multiple arrays including forming an array in a substrate, the array comprising a plurality of deposition domains formed of a deposition material, exposing the array to one or more materials which contain an at least one sample molecule that causes a molecular interaction event with one or more of the deposition samples, and scanning the array utilizing a scanning probe microscope to characterize the molecular interaction events that have occurred between the target sample and the deposition material. [0049] One object of this invention is the construction of relatively small molecular domains with large molecular species. [0050] Another object of this invention is the construction of molecular arrays comprised of molecular domains, each containing as little as a solitary molecule. [0051] Another object of the present invention is an apparatus and method for the creation of a molecular array comprised of one or more molecular domains, each with an area smaller than one micron. [0052] Another object of this invention is the utilization of molecular domain arrays without having to perform a labeling step to allow for the detection of a molecular event. [0053] Another object of this invention is a molecular deposition array that has an effective screening limit at the single molecule level. [0054] Another object of the present invention is a method for using an AFM in a high throughput format to detect and evaluate interactions between molecules. [0055] Another object of this invention is the placement of molecular deposition domains at a defined spatial address. DETAILED DESCRIPTION I. DEFINITIONS [0056] The following are some definitions that may be helpful in understanding the description of the present invention. These are intended as general definitions and should in no way limit the scope of the present invention to those terms alone, but are put forth for a better understanding of the following description. [0057] A. Deposition Material: This is a selected sample placed on a surface that can be recognized and/or reacted with by a target sample. The deposition material will ideally have a change inflicted upon it by one or more target samples that can be detected by later scanning with an SPM. This is the known material placed in the domain. Examples of deposition materials include, but are not limited to, biomolecules, proteins, a variety of chemicals, DNA, RNA, antibodies, or any other substance recognized by one skilled in the art which may have usefulness within the teaching of the present invention. [0058] B. Deposition Domain: A deposition domain is a spot on a surface upon which a deposition material is placed. The domain may be of any size, shape, and pattern and may contain as little as one molecule of the deposition material. These deposition domains may alternatively be referred to as “spots” or “points.” The boundary of the domain is defined by the boundary of the material placed therein. [0059] C. Array: Alternatively referred to using the term “array,” “bioarray,” “molecular array,” or “high density molecular array.” The term array will be used to describe the one or more molecular domains deposited on the surface. [0060] D. Target Sample: A substance with a particular affinity for one or more deposition domains. These target samples may be natural or man-made substances. The target samples may be known or unknowns present in a solution, gas, or other medium. These target samples may bind to the deposition domain or simply alter the deposition in some other cognizable way. Examples of target samples may include, but are not limited to, antibodies, drugs, nucleic acids, proteins, cellular extracts, antibodies, etc. The target medium may likewise be artificially made or, in the alternative, a biologically produced product. [0061] E. AFM: As noted above, AFM's are a type of scanning probe microscope. The AFM is utilized in the present invention as an example of an SPM. The invention, however, is not limited for use with one specific type of AFM, but can also be incorporated for use with SPM's of various makes, models, and technological improvements. [0062] F. Deposition Device: The deposition device of the following description is a modified AFM probe and tip. The basic probe and tip of the AFM is well known to one reasonably skilled in the art. The modified probe and tip that is the deposition device of the present invention may alternatively be referred to herein as “tip,” “probe tip,” or “deposition device.” Other deposition devices can be substituted by one reasonably skilled in the art, including the use of a dedicated deposition device manufactured for the express purpose of sample deposition. II GENERAL [0063] The apparatus and method of the present invention allows for the placement of an at least one deposition sample in an at least one molecular deposition domain forming an array. The method of creating the present invention deposition domain may result in deposition domains smaller than one micron in total area. Furthermore, this method allows the deposition of relatively large molecular species, as large as1kilodalton and larger, without shearing or changing the molecular formation. This array can be exposed to a sample medium that may contain a target sample, the presence of which may be ascertained and characterized by detecting molecular interaction events. The molecular interaction event detection may be performed utilizing an atomic force microscope. [0064] The deposition domains of the present invention may be formed as small or smaller than one micron in area. The present invention allows the direct detection of molecular interaction events in the deposition domain of the array. The molecular interaction event is detected without the need for the labeling of the deposition material or of the target sample. While labeling may still be performed for use with the present invention, the present invention does not require labeling to be utilized. [0065] The present invention utilizes a scanning probe microscope to interrogate the various deposition domains of the present invention array. As the probe is scanned over a surface the interaction between the probe and the surface is detected, recorded, and displayed. If the probe is small and kept very close to the surface, the resolution of the SPM can be very high, even on the atomic scale in some cases. [0066] In the present embodiment, an AFM may be used as the deposition tool, but this does not exclude other types of SPM's being used in alternative embodiments. An unmodified AFM probe has a sharp point with a radius of curvature that may be between 5 and 40 nm. The method herein uses a microfabricated deposition device with an apical radius on the order of 10-50 nm. Due to the small radius of curvature of the deposition device used herein, the spot size generated by the present method can range from larger spots to as small as 0.2 microns or smaller. The difficulties with the prior art method need for labeling, such as with radioactivity, fluorescence, enzymatic labeling, etc., are also avoided. [0067] As one reasonably skilled in the art will appreciate, the molecular material deposited by the present invention may be of almost any size and type. The following materials and methods are not intended to exclude other materials that may be compatible with the present invention, however, the present example is given for better understanding of the scope of the present invention. [0068] Surface Preparation [0069] As shown in FIG. 1, block 10 , and FIG. 2, block 18 , a surface may first be provided. The deposition domains that form the array will be constructed on this surface. The surface used for the deposition of the present embodiment molecular domain should facilitate scanning by an AFM as well as facilitate the deposition of the deposition material. A surface which can accept and bind tenaciously to the deposition material may also be desired. The present embodiment utilizes a solid glass substrate. This solid glass substrate may be a glass slide well known to those reasonably skilled in the art. Other embodiments may use other substrates including, but not limited to, mica, silicon, and quartz. The present embodiment may further cover this surface with a freshly sputtered gold layer. [0070] The ion beam sputtering of gold onto a surface is well known by those reasonably skilled in the art. Sputtering gold may produce an extremely smooth surface upon which a variety of chemistry and molecular binding may be performed. In other embodiments, the gold may be sputtered onto glass coverslips, smooth silicon, quartz or a similar flat surface. The smoothness required of the underlying substrate is a function of the sensitivity requirement of a particular test. For example, detection of a virus particle binding to antibodies on a surface requires only the smoothness of a typical glass coverslip. In contrast, detection of binding of a small ligand to a surface immobilized protein may require a supporting substrate with a surface roughness of one nanometer over an area of several microns. [0071] In alternative embodiments, other surfaces besides that achieved by gold sputtering may be likewise utilized, such as, but not limited to, glass, Si, modified Si, (poly) tetrafluoroethylene, functionalized silanes, polystyrene, polycarbonate, polypropylene, or combinations thereof. [0072] The gold of the present embodiment is sputtered onto the glass surface. This area of gold defines the boundary of the present embodiment array. The deposition material will be deposited in domains contained in this area. [0073] Depositing The Deposition Sample On The Deposition device [0074] With reference to FIG. 1 block 12 , FIG. 2 block 20 , and FIG. 3, the deposition of the sample on the deposition device 40 will be described. The basic shape of the deposition device 40 is shown in FIG. 3. Before the deposition material is formed into a molecular domain on the above surface, the deposition material must first be placed onto the deposition device 40 . The deposition device 40 of the present embodiment may be a deposition device 40 and tip 42 commonly utilized by an AFM. The present embodiment starts with a standard silicon-nitride AFM probe under the tradename “DNP Tip” produced by Digital Instruments, Inc. These probes are generally available and well known in the art. In the present embodiment, the deposition device 40 may be first placed on the deposition instrument. A Digital Instrument, Inc., Dimension 3100 may be used in the present embodiment, controlled by a standard computer and software package known in the art. [0075] In the present embodiment, the deposition instrument may be modified with a microsphere 52 to facilitate the loading (depositing) of the deposition material 56 . While other embodiments may not utilize such a microsphere on the deposition device 40 , attaching a microsphere on the deposition device 40 allows the loading of a greater amount of deposition material upon the deposition device 40 , enabling a greater number of deposition domains 64 to be deposited before reloading with new material. Borosilicate glass spheres up to 25 microns or larger in diameter may be utilized in the present embodiment as the microspohere 52 . [0076] First, a small amount of epoxy resin is placed upon a surface, usually glass. A standard ultraviolet activated epoxy resin, such as Norland Optical Adhesive # 81 , may be utilized, though those reasonably skilled in the art may fine other types of epoxies useful as well. The deposition device 40 is moved by the instrumentation and dipped slightly in the epoxy and withdrawn, retaining a small amount of the epoxy on the tip 42 . As shown in FIG. 4, on another surface 50 are placed a number of the microspheres 52 . Using the instrumentation controls, one or more of the borosilicate glass beads is touched by the end of the deposition device 40 . Because of the epoxy, the microsphere 52 sticks to the end of the deposition device 40 as it is pulled away. The deposition device 40 is then exposed to ultraviolet light to set the epoxy and permanently affix the microsphere glass bead 52 to the tip 42 of the deposition device 42 . As shown in FIG. 5 and 6 , the microsphere 52 may bind to the tip 42 of the deposition device 40 in various places without affecting the present invention. [0077] The present embodiment places one microsphere 52 on the deposition device 40 . This microsphere 52 allows the deposition device 40 to retain more of the material to be deposited on the probe while still allowing the creation of deposition domains 64 on the sub-micron scale. As noted above, as little as one microsphere 52 may be deposited on the tip in the above process. Furthermore, the surface of the microsphere 52 allows for alternative types of surface chemistry to be performed when, in alternative embodiments, the deposition material is being bonded to the surface. [0078] The microspheres 52 used in the present embodiment are commercially available and well known in the art, ranging in size to smaller than 0.05 microns. With a smaller the microsphere 52 , a smaller deposition domain 64 may be achieved, however less sample can be deposited on the tip at any one time, slowing down the construction of the array. Modification of the deposition device 40 may also be accomplished in a number of alternative ways, including spontaneous adsorption of molecular species, chemical derivitization of the AFM tip followed by covalent coupling of the probe molecule to the tip, or the addition of microspheres to the tip which may be coupled to molecules by standard chemistry. In additional embodiments, a laser may be used to locally heat the deposition device 40 and bond microspheres (such as polystyrene spheres) by a “spot welding” technique. [0079] As shown in FIG. 1 block 12 , and FIG. 2 block 20 , after the microsphere 52 is placed on the deposition device 40 , the deposition material 56 may be loaded on the deposition device 40 by forming a capillary bridge 60 . The deposition material 56 may be placed on a surface as shown in FIG. 7 a. This large spot of deposition material 56 can be reused a number of times, depending on the number of domains 64 that are to be created. Though not drawn to scale, FIG. 7 a shows material that may have been micro-pipetted onto a surface for loading on the deposition device 40 . [0080] In one embodiment, the deposition device 40 may be brought into direct contact with the material 56 on the surface. In alternative embodiments, the deposition device 40 and microsphere 52 may be brought into a near proximity to the deposition material 56 on the surface and achieve the same capillary action. The exact distance between the microsphere 52 and the deposition material 56 may vary and still have the formation of a capillary bridge 60 . This depends on conditions like relative humidity, microsphere 52 size, contaminants, etc. In the present embodiment, this distance may vary between touching to several nanometers or more. [0081] The capillary bridge 60 , shown in FIG. 7 b, may be formed by controlling the humidity by timing a blast of humid gas. Longer bursts may result in a greater amount of material to be placed on the tip. Short bursts allow for less material to be used, but must be long enough to effectively transfer deposition material 56 from the surface 62 to the deposition device 40 . The optimal parameters are determined empirically, however a typical time of exposure to the humid gas is on the order of 500 milliseconds or longer. It has also been noted that a capillary bridge 60 may be spontaneously generated when the relative humidity of the air is more than approximately 30%. In cases such as this, it may be advantageous to have a controlled dry environment or to have a stream of dry air flowing over the surface which is interrupted by the humid blast of gas which forms the capillary bridge 60 . In other embodiments, this spontaneous capillary bridge 60 can be used to deposit the deposition material 56 , though less control of the process may result. [0082] In the present invention the humidity may be controlled by several methods known to those reasonably skilled in the art. The present embodiment incorporates a small tube and argon gas source which creates the bridge by rapidly increasing the level of humidity around the probe and the deposition material. The tube of the present embodiment may be a flexible polymer material, such at “Tygon” tubing, with an inner diameter of 0.5 to 1.0 cm. This material is readily available, but other materials that will not introduce contaminants into the deposition material would likewise suffice. The small tube must first be filled with water. [0083] The water used in the present embodiment should be of a highly purified nature, such as purified water with a resistance of 18 megaohms or more. It should be free of particulates by filtration and is usually sterilized by filtration and or autoclaving. Additionally, an argon gas source may be positioned at one end of the tube and may be controlled by the action of a needle valve and solenoid. [0084] The water is then drained from the tube, leaving a humid gas in the tube. When the humidity blast is desired, the solenoid is activated to pulse a discrete amount of humidified argon through the tube and over the probe 40 , deposition material 56 , and surface 62 . As shown in FIG. 7 b, the capillary bridge 60 may be formed between the surface 62 and the deposition device 40 . The deposition device 40 is then moved away from the surface 62 , leaving a small amount of the deposition material 56 on the deposition device 40 , as shown in FIG. 8 a. [0085] As shown in FIG. 8 a, the deposition material 56 is now on the deposition device 40 . Whether the deposition material 56 adsorbs onto the microsphere's 52 surface, the pores, or some other area, may vary depending on the type of microsphere 52 and the deposition material 54 . As shown in FIG. 1 block 14 , the deposition material 56 may now be dried on the deposition device 40 . The drying may be immediate and spontaneous due to the relatively little amount of wet material on the surface of the deposition device 40 . This is, of course, dependent on the relative humidity of the surrounding air. Drying the deposition material 56 on the microsphere 56 may facilitate the deposition of the material 56 on the surface 62 as laid out in the next step. For labile samples, drying could result in inactivation, and should be avoided, but this is not the case for robust samples such as antibodies, peptides and nucleic acids. [0086] In an alternative embodiment, the deposition tip may be loaded with the deposition material 56 by direct immersion. The tip of the probe may be immersed in a solution containing up to 50% glycerol, 0.1-5 mg/ml of the deposition sample, and a buffer-electrolyte such as Tris-IICl at IICl at pH 7.5. A small amount of the above solution may be made by standard bench chemistry techniques known to those skilled in the art. Typically 1-10 microliters are made. Because of the nature of solutions, when the probe is dipped into the solution and withdrawn a small amount of the solution will cling to the surface of the tip in a manner known to those reasonably skilled in the art. In still further embodiments, other solutions, such as 10mM NaCl and 1mM MgCl 2 , phosphate buffered saline, or a sodium chloride solution, may be substituted by those reasonably skilled in the art. Alternative methods for loading the deposition material 56 on the deposition device 40 include spraying, chemically mediated adsorption and delivery, electronically mediated adsorption and delivery, and either passive or active capillary filling. [0087] In still further embodiments, other probes may also be used, for example, AFM probes lacking a tip altogether (tipless levers), may also be used. The type of probe used may impact the spatial dimensions of the deposition domain 64 and may be influenced by the choice of the deposition sample. [0088] Depositing the Sample On the Surface [0089] The next step in creating the deposition domain 64 and array 66 is depositing hte sample on the surface. See FIG. 1 block 16 and FIG. 2 block 22 . Varying the humidity level surrounding the deposition device 40 and deposition material 56 may be taken advantage of to deposit the deposition material 56 onto the surface in a deposition domain 64 less than one micron in area. The capillary bridge 60 is illustrated by FIG. 8 b. This step may be performed in much the same way as depositing the deposition material 56 on the deposition device 40 . The degree of binding to the surface and the deposition device 40 is a function of the hydrophilicity and hydrophobicity of the two surfaces. Therefore, it may often be desirable to use deposition tools and surfaces that are free of oils and other hydrophobic contaminants to facilitate wetting of both surfaces. [0090] Utilizing the AFM and the control computer and software, the deposition device 40 , with the deposition material 56 , may be brought into contact, or close proximity, with the deposition surface. The humid gas may then be released by activation of the solenoid. In the present embodiment the humidity is ramped up, and the capillary bridge 60 formed, for a time of approximately 400 milliseconds or less, depending on the amount of material the user wishes to deposit. The spots are on the sub-micron scale because the contact surfaces are on the order of microns or smaller and the degree of sample diffusion (which determines the final size of the deposition domain) is carefully controlled by regulating the amount and timing of the humid gas burst. When depositing the deposition sample 56 on the surface, in order to better control the length of time the capillary bridge 60 exists, a tube of dry air may be blown over the area by a solenoid in rapid succession after the humid air. This results in a very short burst of humid air, a capillary bridge 60 , and then the termination of the capillary bridge 60 , all in a very short time period. As illustrated in FIG. 9, when the deposition device 40 is withdrawn, and the bridge 60 severed, a very small amount of the deposition material 56 has been deposited on the surface 62 in a deposition domain 64 . The transfer of large macromolecules may be achieved utilizing the burst of humid gas. As will be appreciated by one reasonably skilled in the art, the capillary bridge 60 may be broken by withdrawing the deposition device 40 or by the blast of dry air. [0091] Because of the fine control of the deposition device 40 that may be possible with the AFM instrumentation, the exact surface spot in which the deposition takes place may be noted. Noting the surface point for each deposition domain 64 may ameliorate the detection of the molecular interaction event caused by the target sample. The pattern writing program can be one that is provided by an AFM manufacturer (e.g., the Nanolithography program provided by Digital Instruments, Inc.) or it can be created in-house. In the latter case, one example is to use a programming environment such as Lab View (National Instruments) with associated hardware to generate signal pulses which control the positioning of the deposition probe. [0092] The steps laid out above produce the deposition domain 64 of the present embodiment. Repeating these steps with one or more deposition materials 56 , FIG. 2 block 26 , produces the array 66 of the present invention. This array is shown in FIG. 10. The number and size of the deposition domains 64 may be varied depending on the desire of the user. [0093] One advantage to the present embodiment is the small size of the deposition domain 64 produced by the method. Furthermore, because of the manner in which the array 66 is produced, the user may be able to record and track the position of each of the particular deposition domains 64 . Finally, the above method allows the deposition of as little as a single macromolecule, which previous methods were unable to perform. [0094] Once the array 66 has been formed, the user may desire to immediately utilize the array 66 on site, or may desire shipment of the array 66 for exposure to a sample medium at another location. The array 66 produced by the above steps may be ideal for shipment to a location, exposure, and return shipment for the scanning by an AFM. [0095] Subsequent Depositions [0096] In an alternative embodiment, the probe may be reloaded with a second deposition material 56 after one or more molecular domains are created with the first deposition material 56 . FIG. 2 block 26 . Using the probe with a variety of deposition materials 56 enables the creation of a number of deposition domains 64 on one surface. The different deposition materials 56 in the molecular domains that are deposited on the surface form the array 66 of the present invention. Because of the size of the molecular domain containing the deposition material 56 , the molecular domains can be placed on the surface in a an ultra high density array 66 , as shown in FIG. 10. In the present embodiment of this invention, the pitch (the distance from the center of one domain to the center of the next domain) of the molecular domains may be as small or smaller than one micron. The array 66 produced with these small molecular domains may be easily scanned by the AFM array 66 after the array 66 is exposed to the sample medium containing the target sample in the next step. Furthermore, the small sized array 66 requires exposure to a smaller amount of the sample medium of the next step, conserving both the deposition material 56 and the medium material. [0097] The number of times the probe may be reloaded in this alternative embodiment may be only limited by the surface size and the number of samples the user desires to deposit. As will be appreciated by those skilled in the art, this ultra high density array 66 presents a unique advantage. [0098] Cleaning the Probe [0099] Before the probe is reloaded with subsequent deposition samples, the probe must be cleaned. FIG. 2 block 24 . The probe of the present embodiment AFM may be cleaned in several ways. In the present embodiment, the very tip of the probe is immersed in a small aliquot of a cleaning solution. The present embodiment cleaning step utilizes pure water as the solution. A few microliters of water is pipetted onto a surface and, using the instrumentation's piezo device (which is utilized to help the AFM scan surfaces), the tip is oscillated at up to 1000 Hz or more. Resonating the probe at 1000 hertz will effectively sonicate the tip, helping to effectuate reusing the tip to deposit other deposition materials 56 . [0100] Exposing the Array To a Sample Medium [0101] Once a high density array 66 is formed by the present invention, the array 66 may be exposed to a sample medium. FIG. 2 block 28 . The sample medium may contain a target sample that the user has placed therein. In other types of experiments, the user may be looking for the presence of an unknown target sample, utilizing the array 66 of the present invention to test for its presence. The usefulness of such arrays 66 are well known to those reasonably skilled in the art. [0102] The array 66 may be dipped in a solution or exposed to a gas. The solution may include, but is not limited to, waste water, biological materials, organic or inorganic user prepared solutions, etc. The exposure time of the array 66 to the medium depends on what types of molecular interaction events the user may be studying. The target sample tested for should ideally cause a readable molecular change in one or more of the deposition materials 56 of the molecular domains placed on the array 66 . These molecular changes may include binding, changes in stereochemical orientation in morphology, dimensional changes in all directions, changes in elasticity, compressibility, or frictional coefficient, etc. The above changes are what the AFM scans and reads in the next step of the present embodiment. [0103] Molecular Event Detection [0104] After the molecular deposition array 66 is exposed to the test medium, it may be scanned by the AFM. See FIG. 2 block 30 . Use of an AFM in this manner to characterize a material deposited on a surface is well known to those reasonably skilled in the art. The present embodiment may utilize one scan for every deposition domain 64 of the array 66 to look for changes in the recorded features of the domains. Furthermore, the AFM may look at specific portions of the array 66 using site locators. As will be appreciated by one skilled in the art, various methods may be used to undertake the scanning of the array 66 of the present invention. [0105] After the scan is taken, the scan must be analyzed. FIG. 2, block 32 . The present embodiment utilizes the detection of changes in height at defined spatial addresses, as described by Jones et al., supra. As shown in FIG. 11, height changes only occur at those addresses containing deposition material 56 to which the target sample is capable of binding. Since the identity of the molecules at each of the sample addresses is known, this process immediately identifies those deposition materials 56 capable of binding to the target sample. In FIG. 11, point 66 shows the normal height of the deposition domain 64 as scanned by the AFM. Point 68 shows how the AFM will recognize some feature that the molecular interaction event has affected in the deposition domain 64 . [0106] In addition, the AFM can measure whether new materials have bonded to the deposition material 56 by testing for changes in shape (morphology) as well as changes in local mechanical properties (friction, elasticity, compressibility, etc.) by virtue of changes in the interaction between the probe and the surface. The typical parameters detected by an AFM include height, torsion, frequency (the oscillation frequency of the AFM probe in AC modes of operation), phase (the phase shift between the driving signal and the cantilever oscillation in AC modes) and amplitude (the amplitude of the oscillating cantilever in AC modes of operation). [0107] The AFM scan may also be used to tell when the probe is interacting with different forces of adhesion (friction) at different domains on the surface. This interaction force is a consequence of the interaction between the molecules on the probe and on the surface. When there is a specific interaction, the force value is typically higher than for non-specific interactions, although this may not be universally true (since some non-specific interactions can be very strong). Therefore, it may be useful to include both known positive and negative control domains in the scan area to help distinguish between specific and non-specific force interactions. The target sample may affect the deposition material 56 that can be read by this scanning technique. A still further embodiment may directly measure the interaction forces between a molecular probe coupled to the AFM tip and the surface. The direct measurement of molecular unbonding forces has been well described in the art in addition to measuring changes in the elasticity. [0108] In the screening methods described above, once it has been established that a molecular binding event has occurred, changes in the degree of binding upon introduction of additional sample molecules may also be analyzed. The potential for a third molecular species to enhance or inhibit a defined molecular interaction is of utility in locating new drugs and other important effectors of defined molecular interactions. [0109] In the above examples an AFM is used for illustration purposes. The type of deposition instrumentation incorporated into the present invention is not limited to AFM's, or other types of SPM's. In one alternative embodiment, a dedicated deposition instrument may be used which may provide for extremely accurate control of the deposition probe. In this alternative embodiment, a DC stepper motor and a piezoelectric motion control device may be incorporated for sample and probe control. In still further embodiments, a force feedback system may be included to minimize the force exerted between the deposition tool and the surface. [0110] One advantage to the present invention is the elimination of the labeling step required in other array 66 techniques. Radioactive and fluorescent labeling may be cost prohibitive and complex. The present invention eliminates the need for the labeling of molecular deposition domains 64 in an array 66 . [0111] Another advantage to the present invention is the creation of molecular domains in an array 66 wherein each domain has a deposition area of less than one micron. Since the size of each domain is extremely small, a large number of domains may be placed in a small area, requiring less materials, a smaller medium sample for exposure, and the ability to perform a quicker scan. [0112] Another advantage to the present invention array 66 is the ability to quickly scan for multiple molecular events in a reasonably short period of time. III ALTERNATIVE DEPOSITION EXAMPLES [0113] The following are a few of the variations in the deposition method and array 66 apparatus that may be used within the scope of the present invention. These examples are given to show the scope and versatility of the present invention and are not intended to limit the invention to only those examples given herein. In each of these examples, the deposition material 56 may be deposited on the deposition device 40 and then to the surface utilizing the method described above, however the surface may be coated with other materials that will react in some way with the deposition material 56 , to bind the latter to the surface in the deposition domain 64 . [0114] A. Surface Modification [0115] One alternative embodiment for the covalent tethering of biomaterials to a surface for use in the present invention may be to use a chemically reactive surface. Such surfaces include, but are not limited to, surfaces with terminal succinimide groups, aldehyde groups, carboxyl groups, vinyl groups, and photoactivatable aryl azide groups. Other surfaces are known to those reasonably skilled in the art. Biomaterials may include primary amines and a catalyst such as the carbodiimide EDAC (1-ethyl-3-[3-dimethylaminopropyl]carbodiimide). Furthermore, the spontaneous coupling of succinimide, or in the alternative, aldehyde surface groups, to primary amines at a physiological pH may be incorporated for attaching molecules to the surface. In still another embodiment, photoactivatable surfaces, such as those containing aryl azides, may be utilized. These photoactivatable surfaces form highly reactive nitrenes that react promiscuously with a variety of chemical groups upon ultraviolet activation. Placing the deposition sample on the surface and then activating the material can create deposition domains 64 in spots or patterns, limited only by the light source activated. [0116] Another embodiment for the tenacious and controlled binding of biomaterials to surfaces is to exploit the strong interactions between various biochemical moieties. For example, histidine binds tightly to nickel. Therefore, both nucleic acid and protein biomaterials may be modified using recombinant methods to produce runs of histidine, usually 6 to 10 amino acids long. This His-rich domain then allows these molecules to bind tightly to nickel coated surfaces. Alternatively, sulfhydryl groups can be introduced into protein and nucleic acid biomaterials, or preexist there, and can be used to bind the biomaterials to gold surfaces by virtue of extremely strong gold-sulfur interaction. It is well documented that gold binds to sulfur with a binding force comparable to that of a covalent bond. Therefore, gold-sulfur interactions have been widely exploited to tether molecules to surfaces. Jones, V. W., J. R. Kenseth, M. D. Porter, C. L. Mosher, and E. Henderson, Microminiaturized Immunoassays Using Atomic Force Microscopy and Compositionally Patterned Antigen Arrays 66 , Anal Chem. 1998, p. 1233-41. [0117] B. Aptes [0118] In this alternative embodiment, the surface may be treated with APTES (aminopropyl triethoxy silane). The APTES placed on the surface may present positively charged amino groups that can bind tightly to a negative charge. Materials such as DNA and RNA containing negatively charged groups may therefore bond to the surface after the APTES treatment. The details of the adsorption mechanism involved in this spontaneous attachment are not well defined. Therefore, in alternative embodiments, it may be advantageous to deposit biomaterials onto surfaces that can be covalently or otherwise tenaciously coupled to the target sample. DNA and RNA bind through interaction between their negative net charge and the net positive charge of the APTES surface. [0119] C. Photochemical Sample Deposition [0120] In this alternative embodiment, glass surfaces may be modified sequentially by two compounds, aminopropyltriethoxysilane (APTES) and N-5-azido-2-nitrobenzoyloxysuccinimide (ANB-NOS). The glass may first be treated with APTES to generate a surface with protruding amino groups (NH 2 ). These groups may be then reacted with the succinimide moiety of ANB-NOS in the dark. These steps produce a surface with protruding nitrobenzene groups. The photosensitive surface may be then reacted with the first deposition material 56 in the dark, then a focused light source, like a laser, may be used to illuminate a portion of the surface. These acts result in localized covalent binding of the first deposition material 56 to the surface. The deposition material 56 not bonded to the surface may then be washed away and second deposition material 56 added by repeating the process. Reiteration of this process results in the creation of a biomolecular array 66 with address dimensions in the 1 micron size range. A limitation of this deposition method is that the sample size is dependent on the size of the illuminating light field. [0121] A variation of the above embodiment may be to utilize the deposition device 40 and humidity ramping deposition technique described to place various molecular species at defined locations in the dark. After construction of the desired array 66 , the entire surface is exposed to light, thereby cross linking the molecular species at discrete spatial domains. This process may overcome the spatial limitation imposed by use of a far field laser or other type of light beam. [0122] D. Photocoupling [0123] In this embodiment a near field scanning optical microscope (NSOM) may be used to supply the light energy necessary to accomplish photocoupling of the sample molecule to a surface at a defined spatial address. The NSOM may overcome the diffraction limit which constrains the address size created by far field photocoupling as described in Example 2. The photoactive surface is prepared as described in Example II. The first molecule to be coupled is added to the surface and subjected to a nearfield evanescent wave emanating from the aperture of the NSOM. The evanescent wave energy may then activate the photosensitive surface and result in coupling of the sample molecules to a spatial address in the 10 to 100 nm size range. The first sample molecule is washed away and the process repeated with a second sample molecule. Reiteration of this process may result in the production of an array 66 of sample molecules coupled at spatial addresses with submicron dimensions. [0124] An alternative approach may be to utilize both the sample manipulation and near field light delivery capabilities of the NSOM. In this approach, the NSOM probe may be first loaded with a molecular species as described in Example I. Then the same probe is used to provide the light energy to couple the molecule to the surface. The probe may then be washed and reused to create a spatial array 66 of molecular species covalently coupled to defined domains. [0125] One advantage of coupling the deposition material 56 to the surface may be that the molecule may remain attached at a defined spatial domain even under stringent wash and manipulation conditions. Moreover, by coupling the molecule, the orientation of the molecules on the surface may be controlled by the careful selection of a tethering method. [0126] Yet another advantage to coupling the molecule is that by controlling the coupling chemistry, the minimization of the chances of surface induced molecular denaturation may be achieved. Coupling the molecules to the surface may be especially advantageous when depositing biomolecules. [0127] The information and examples described herein are for illustrative purposes and are not meant to exclude any derivations or alternative methods that are within the conceptual context of the invention. It is contemplated that various deviations can be made to this embodiment without deviating from the scope of the present invention. Accordingly, it is intended that the scope of the present invention be dictated by the appended claims rather than by the foregoing description of this embodiment. [0128] All publications cited in this application are incorporated by reference in their entirety for all purposes.

The invention is a method for the formation and analysis of novel miniature deposition domains. These deposition domains are placed on a surface to form a molecular array. The molecular array is scanned with an AFM to analyze molecular recognition events and the effect of introduced agents on defined molecular interactions. This approach can be carried out in a high throughput format, allowing rapid screening of thousands of molecular species in a solid state array. The procedures described here have the added benefit of allowing the measurement of changes in molecular binding events resulting from changes in the analysis environment or introduction of additional effector molecules to the assay system. The processes described herein are extremely useful in the search for compounds such as new drugs for treatment of undesirable physiological conditions. The method and apparatus of the present invention does not require the labeling of the deposition material or the target sample and may also be used to deposit large size molecules without harming the same.

CROSS-REFERENCE TO RELATED APPLICATIONS This claims the benefit of priority of U.S. Provisional Patent Application No. 62/260,178 filed on Nov. 25, 2015 and U.S. Provisional Patent Application No. 62/120,841 filed on Feb. 25, 2015; each of which is incorporated herein by reference in its entirety. This is related to Non-Provisional patent application Ser. No. 14/949,820 filed on Nov. 23, 2015 and Non-Provisional patent application Ser. No. 15/007,154 filed on Jan. 26, 2016; each of which is incorporated herein by reference in its entirety for all purposes. FIELD OF THE INVENTION This invention relates to mounting system for photovoltaic modules or so-called “solar panels.” SUMMARY OF THE INVENTION The present invention relates to photovoltaic mounting systems, and in particular mounting systems adapted to form a chemical flashing about any roof penetrations associated with the mounting system. In various embodiments, the system includes a cartridge of sealant material that provides a chemical flashing when mounted on a roof surface. In various embodiments, the cartridge of sealant material is discharged between the photovoltaic mounting system and roof surface by the torqueing down of a mechanical fastener connecting the mounting system to the roof surface. In various embodiments, the mechanical fastener can be a lag bolt, while in other embodiments, the mechanical fastener can a hanger bolt. In various embodiments, the system can further include a compressing member or plate that presses against a base assembly to compress the sealant cartridge, which forces the sealant through apertures defined in the base assembly to form a chemical flashing on the roof surface. The chemical flashing is formed to provide a water resistant seal around the mechanical fastener. In various embodiments, the compressing plate can be a rigid disk, although in various other embodiments, the compressing plate can be formed in different shapes. In various embodiments, the system can include a photovoltaic module mounting bracket having a photovoltaic module coupling device that is attached to the base assembly. In some embodiments, the module mounting bracket is attached to the base assembly via a nut and the top threaded portion of the hanger bolt attaches the base assembly to the roof surface. The base assembly can be formed in a circular shape resembling a puck, although it is appreciated that the base assembly can be formed in various non-circular shapes (e.g. oval, square, rectangular) as needed for a particular application. In one aspect, the invention relates to a photovoltaic mounting system for mounting on a roof surface that includes a base assembly adapted to couple with and support a mounting bracket supporting a photovoltaic module coupling device. The base assembly includes a through-hole for insertion of a mechanical fastener. In various embodiments, the base assembly includes a sealant guide, a compressing member or plate, and a sealant cartridge containing a flowable sealant sealed. In various embodiments, the sealant cartridge is held between the sealant guide and the compressing member within the base assembly without requiring any additional separate coupling members to maintain the assembly. One or more of the sealant guide, the base and the compressing plate can include one or more coupling features for releasably securing the components of the base assembly together without requiring any additional separate coupling member, such as a mechanical fastener or other fastening member. In various embodiments, the base assembly includes a sealant guide having a first set of coupling features that releasably couple with the sealant cartridge or the compressing plate to hold the base assembly together via the one or more coupling features. The first of coupling features can include multiple tabs extending from or near an outer periphery of the sealant guide towards the compressing plate that are adapted to releasably engage with an outer periphery of the compressing plate to maintain the sealant cartridge between the sealant guide and the compressing plate. The compressing plate can include one or more openings along the periphery thereof that are arranged to receive a distal retention feature on each of the plurality of tabs. In various embodiments, each of the plurality of tabs of the first set includes a release feature on a distal end thereof to facilitate manual release of the compressing member by pressing against the release features of the plurality of tabs. In various embodiments, the base assembly includes a base adapted to releasably couple to the sealant guide by a second set of coupling features of the sealant guide. The sealant guide includes a central hole for passage of the mechanical fastener and a series of apertures distributed radially about the central hole to facilitate uniform distribution of flowable sealant around any roof surface penetration through which the mechanical fastener extends when mounted on the roof surface. The base also includes a central hole for passage of the mechanical fastener and multiple openings distributed about the central hole that are aligned with the plurality of apertures in the sealant guide when mounted on the roof surface to allow flow of sealant therethrough. In various embodiments, the second set of coupling features comprises a plurality of tabs extending towards the base, each of the tabs having a distal retention feature adapted to engage an edge of the multiple openings in the base. In various embodiments, the retention feature is defined as an outwardly extending wedge shaped portion positioned to facilitate lateral deflection of the tabs when the guide is pressed against the base so as to provide a snap-fit coupling between the guide and the base. In various embodiments, the base has an underside recess on a roof-facing side that defines a space between the base and the roof when mounted thereon for flowable sealant to fill so as to form the chemical flashing. In addition, a sealant ring can be used to define and seal a space between the base and roof surface in which the chemical flashing is formed. In another aspect, the photovoltaic mounting system includes a base assembly having a sealant cartridge with a breakable seal on a roof facing side to facilitate directionally controlled release of flowable sealant through the seal upon fastening of the base assembly onto the roof. The base assembly can further include a sealant guide for supporting that sealant cartridge and securing the sealant cartridge to a base or the guide can be integrated with the base. The sealant guide can include one or more puncture tubes with one or barbs directed towards the breakable seal to facilitate breaking of the seal upon fastening of the base assembly to the roof surface. In various embodiments, the base assembly includes a compressing member disposed atop a collapsible sealant cartridge. The compressing plate can be defined as a compressing plate having a planar surface for engaging and pressing against the sealant cartridge. The top of the compressing plate facing away from the sealant cartridge can be defined as a convex outer surface face to inhibit accumulation of rain and/or debris when mounted on the roof surface. Typically, the compressing plate is defined has a circular shape, although it is appreciated that the compressing plate can be formed in various other non-circular shape. In various other embodiments, the compressing plate is defined as a bell-type shape having an outer periphery that extends further below an interior portion that engages against the top of the sealant cartridge. This bell-type shape allows the outer periphery of the compressing plate to seal against the roof and/or a sealant ring on the roof so as to enclose the compressed sealant reservoir therein and contain any excess sealant extruded when the assembly is mounted onto the roof surface. In various embodiments, a photovoltaic mounting system for mounting to a roof surface includes a base assembly adapted to couple with and support a mounting bracket supporting a photovoltaic module coupling device. The base assembly includes a through-hole for insertion of a mechanical fastener, such as a lag bolt or a hangar bolt. In various embodiments, the base assembly includes a base, a compressing member, a sealant guide having a first set of coupling features adapted to releasably couple with the compressing member and a sealant reservoir containing a flowable sealant sealed. The sealant cartridge is held between the sealant guide and the compressing member by the first set of coupling features. The first set of coupling features include a plurality of protrusions fittingly received within corresponding openings in the compressing member. In various embodiments, each of the tabs of the first set includes a release feature on a distal end to facilitate manual release of the compressing member by pressing against the release features of the plurality of tabs. In various embodiments, the photovoltaic mounting system includes a base assembly having an integrated sealant guide and base. In some embodiments, the integrated sealant guide base can further include an integrated sealant reservoir. In other embodiments, the sealant guide base can be used with a removable sealant cartridge. In various embodiments, the sealant guide, sealant reservoir and base are integrated within a single component having ribs or gussets that provide sufficient support to maintain sealed sealant reservoir yet allow directionally controlled collapse of the reservoir when the base assembly is fastened to the roof surface. In various embodiments, the photovoltaic mounting system includes a base assembly with a sealant cartridge and a reinforcement ring disposed about the cartridge. The reinforcing ring is adapted to provide reinforcement against blow-out of sealant through a side-wall of the sealant cartridge. In various embodiments, the reinforcing ring is adapted to fittingly receive the sealant cartridge and extends above the roof surface a lower height than the cartridge so as to allow compression of the sealant cartridge during installation. In various embodiments, the photovoltaic mounting system includes a photovoltaic module coupling device, a mounting bracket supporting the photovoltaic module coupling device, and a base assembly releasably coupled to the mounting bracket and having a through-hole for insertion of a mechanical fastener. The base assembly can include a sealant guide, a compressing member, and a sealant cartridge containing a flowable sealant sealed. In various embodiments, the sealant cartridge is held between the sealant guide and the compressing member within the base assembly without requiring any additional separate coupling members to maintain the assembly. BRIEF DESCRIPTION OF THE DRAWINGS FIGS. 1 and 2 illustrate an assembled view and an exploded view of a photovoltaic mounting system adapted to form a chemical flashing according to an exemplary embodiment. FIGS. 3A-3C illustrate several views of a base assembly of a photovoltaic mounting system according to an exemplary embodiment. FIG. 4 illustrates an exploded view of a base assembly of a photovoltaic mounting system according to an exemplary embodiment. FIGS. 5A and 5B illustrate an exploded view and an exploded view, respectively, of a base assembly of a photovoltaic mounting system according to an exemplary embodiment. FIGS. 6A-6C illustrate sequential views showing installation of a base assembly of a photovoltaic mounting system according to an exemplary embodiment. FIGS. 7A and 7B illustrate an exploded view and an assembled view, respectively, of a photovoltaic mounting system adapted to form a chemical flashing according to an exemplary embodiment. FIGS. 8 and 9 illustrate an assembled view and an exploded view, respectively, of a photovoltaic mounting system adapted to form a chemical flashing according to another exemplary embodiment. FIG. 10 illustrates an exploded view of a base assembly of the photovoltaic mounting system of FIG. 9 . FIG. 11 illustrates select components of the base assembly of the photovoltaic mounting system of FIG. 9 . FIG. 12A illustrates an exploded view of a base assembly of a photovoltaic mounting system according to another exemplary embodiment. FIG. 12B illustrates an exploded view of a base assembly of a photovoltaic mounting system according to yet another exemplary embodiment. FIG. 13 illustrates several views of a base of the base assembly shown in FIG. 12B . FIGS. 14A and 14B illustrate bases for use in a base assembly of a photovoltaic mounting system according to alternative embodiments. FIG. 15 illustrates a photovoltaic mounting system according to another exemplary embodiment. FIG. 16 illustrates an exploded view of the photovoltaic mounting system shown in FIG. 15 . FIG. 17A illustrates an exploded view of the base assembly of the photovoltaic mounting system shown in FIG. 15 . FIG. 17B illustrates a detailed view of the pins of the sealant reservoir heat bonded to corresponding holes in compressing plate of the base assembly in FIG. 17A . FIG. 18 illustrates an exploded view of the base assembly components according to another embodiment of a photovoltaic mounting system. FIGS. 19A-19C illustrate sequential cross-sectional views of an exemplary photovoltaic mounting system before, during and after installation according to various embodiments. FIG. 20 illustrates an underside view of an integrated guide base according to another embodiment of a photovoltaic mounting system. FIGS. 21A and 21B illustrate a cross-sectional detailed and an underside view, respectively, of the integrated guide base in FIG. 20 indicating a sealant flow path during installation according to various embodiments. FIG. 22 illustrates a photovoltaic mounting system according to another exemplary embodiment. FIG. 23 illustrates an exploded view of the photovoltaic mounting system of FIG. 22 . FIG. 24A illustrates an exploded view of the base assembly of the photovoltaic mounting system of FIG. 22 . FIG. 24B illustrates an assembled view of the base assembly of the photovoltaic mounting system of FIG. 22 . FIGS. 25A and 25B illustrate perspective views of the top-side and the bottom, roof-facing side, respectively, of an integrated guide base of the photovoltaic mounting system of FIG. 22 . FIG. 26 illustrates a cross-sectional side of the integrated guide base of the photovoltaic mounting system of FIG. 22 . DETAILED DESCRIPTION The following description is intended to convey a thorough understanding of the embodiments described by providing a number of specific embodiments and details involving PV mounting hardware for shingled roofs. It should be appreciated, however, that the present invention is not limited to these specific embodiments and details, which are exemplary only. It is further understood that one possessing ordinary skill in the art, in light of known systems and methods, would appreciate the use of the invention for its intended purposes and benefits in any number of alternative embodiments, depending upon specific design and other needs. Referring now to FIGS. 1-8 , these Figures show various views of a photovoltaic mounting system according to various embodiments of the invention. As shown in FIG. 1 , mounting system 100 includes a base portion 110 , mounting bracket 120 and photovoltaic module coupling device 130 . As can be seen in the exploded view of FIG. 2 , a fastener, such as hanger bolt 121 , is used to fasten mounting bracket 120 to base portion 110 and to mount base portion 110 to the roof surface. Bolt head 121 a engages a top surface of base portion 110 to mount onto the roof surface and mounting bracket 120 is secured to base portion 110 by nut 112 threaded onto the upper threaded region of hanger bolt 121 . As shown in FIG. 3A-3C , base portion 110 includes sealant cartridge 115 that sits between compressing plate 116 and base 112 . Compressing plate 116 may take the form of a bell housing or simply be a plate or can be formed in any suitable shape for pressing against cartridge 115 so as to release the flowable sealant thereby forming the chemical flashing. Base 112 can be formed in a circular, puck shape, although it is appreciated that base 112 can also be formed in various other non-circular shapes as well. In some embodiments, base 112 is formed of a durable, rigid, corrosion resistant material, for example a metal alloy, such as steel, aluminum or hard plastic. Sealant cartridge 115 contains a flowable sealant that is released upon mounting of base assembly 110 to form the chemical flashing. In various embodiments, base 112 includes a recess on its bottom, roof-facing side, that circumscribes its perimeter and that is dimensioned to receive the top of sealant ring 111 to keep sealant material captured under base portion 110 when the assembly is attached to a roof or other support surface. Sealant ring 111 can be attached to base 112 by any suitable means, for example a pressure-sensitive adhesive. As shown in FIGS. 3A-4 , base portion 110 can be defined as a stacked assembly, although it is appreciated that in various other embodiments some or all of the components of the assembly can be integrated. As shown in FIGS. 3A-3C and 4 , base 112 can include center hole 113 for passage of a mechanical fastener and apertures 113 A to allow extrusion of the flowable sealant therethrough. Apertures 113 A may be distributed around center hole 113 to allow for even distribution of sealant material under base 112 . In this embodiment, apertures 113 A are distributed radially about center hole 113 to provide more uniform distribution of sealant about the roof penetration that the fastener extends through. While three apertures are shown here, each defined in a trapezoidal-shape, it is appreciated that the apertures could be formed in various differing shapes and numbers. For example, apertures 113 A can be formed also as circular holes or could be formed as a single opening extending partly or entirely about center hole 113 . As can be seen in FIG. 4 , cartridge 115 comprises a cylindrical-shaped structure with a center through-hole 115 A. Cartridge 115 can be formed of any suitable material, for example plastic, that can contain a flowable sealant in a sealed state. In various embodiments, the housing of cartridge 115 can be formed, partly or entirely, of a material that can be crushed or collapsed so as to allow release of the flowable sealant upon mounting of base portion 110 to the roof. In various embodiments, one side of cartridge 115 facing towards base 112 may be covered with foil or other material that is strong enough to provide an airtight seal to prevent the sealant form curing but breakable enough to easily penetrated or ruptured during installation to release the sealant. A plastic bracket such as sealant carrier or guide 114 may surround cartridge 115 , keep center-hole 115 A of cartridge 115 over center opening 113 in base 112 , and also function as mechanical fastener to connect cartridge 115 and compressing plate 116 to base 112 to form a single assembly. In various embodiments, sealant guide 114 includes one or more coupling features that act as mechanical fasteners to couple guide 114 to one or both of compressing plate 116 and base 112 with sealant cartridge 115 secured therebetween. In these embodiments, the one or more coupling features are defined as one or more tabs, typically a series of tabs distributed about the periphery of guide 114 . As can be in seen in FIG. 4 , guide 114 include multiple tabs 114 B that extend upwards toward compressing plate 116 . Each tab can include a retention feature 14 C on a distal end thereof. Retention feature 14 C can be defined as an inwardly bent or curved end adapted to engage a top, outer surface of compressing plate 116 sufficiently to couple guide 114 with compressing plate 116 . In some embodiments, tabs 114 B are adapted to receive and fit over an outer periphery of compressing plate 116 and engage an outer surface, such as shown in FIG. 3A . Tabs 114 B are formed of a material with sufficient rigidity and strength to resiliently deflect to receive compressing plate 116 and apply enough tension to securely couple compressing plate 116 to guide 114 with sealant cartridge 115 held in between. In some embodiments, tabs 114 B are adapted to interface with corresponding retention features 116 B within compressing plate 116 . In this embodiment, the corresponding retention features 116 B are defined as square openings dimensioned to receive the distal retention feature of tabs 114 B. It is appreciated that the assembly can be designed so that tabs 114 B interface with the corresponding retention features 116 B from outside the periphery, as shown in FIG. 3A , or from inside the periphery, as shown in FIG. 3B . Distal retention features 114 C can be defined as wedge-shaped portions that are positioned so that an angled portion deflects tabs 114 B when compressing plate 116 is pressed onto guide 114 until the wedge-shaped portion is received into the square openings, such as in a snap-fit type coupling. In such embodiments, the wedge-shaped portion can be dimensioned to extend beyond the square openings when guide 114 is snap-fit coupled to compressing plate 116 to allow a user to disassemble base portion assembly 110 by pressing on the portions of tabs 114 B protruding from compressing plate 116 . In various embodiments, guide 114 can further include coupling features for securing base 112 to guide 114 . As shown in FIG. 4 , such coupling features can be defined as multiple tabs 114 A distributed along the periphery of guide and extending towards base 112 . Similar to the mechanism described above with respect to tabs 114 B, tabs 114 A are shaped so as to be resiliently received within corresponding retention features within base 112 . In this embodiment, the corresponding retention features are also apertures 113 A through which sealant is extruded. As can be seen in FIG. 4 , tabs 114 A are positioned to be received along an outside edge of each of apertures 113 A and include distal retention feature 114 D defined as a wedge-shaped portion that facilitates lateral deflection of tabs 114 A until distal retention feature 14 D is received along the lower edge of apertures 113 . While in this embodiment, the corresponding features of base 112 are integrated with apertures 113 A, it is appreciated that base 112 could include separate retention features, for example a series of openings similar to those in compressing plate 116 . In any of the embodiments herein, it is appreciated that one or more retention features, such as tabs 114 A and 114 B, can be used to secure the elements of base portion 110 within an assembly. Such retention features can be adapted to permanently secure the components together or to releasably secure the components together so as to allow an end-used to disassemble base portion if needed. While retention features 116 B are shown as square or rectangular openings and tabs 114 A and 114 B are shown as having rectangular cross-sections, it is appreciated that various other shapes could be used in keeping with retention mechanisms described above. As shown for example in FIG. 5 , guide base 114 may include a set of openings 114 E which overlap or match up with apertures 113 A of base 112 so that flowable sealant flows through both openings 114 E and base 113 A when cartridge 115 is compressed. Guide 114 can further include a set of tabs 114 A on the base-facing side that detachably couple guide base 114 to base 112 . Also, as seen in FIG. 5 , base assembly can further include reinforcing ring 118 , which is a rigid ring adapted to fit around cartridge 115 when fitted within guide base 114 . Reinforcing ring 118 is made of a suitable material and dimension to provide resistance to the lateral flow of sealant through the sidewall of cartridge 115 when cartridge 115 is compressed against base 112 otherwise known as a “blow-out.” As seen here, reinforcing ring extends only partly along the side to allow cartridge to be compressed to about the height dimension of the reinforcing ring. In such embodiments, guide base 114 may also include a set of upward-facing tabs 114 B, that face away from base 112 , that engage a compressing member such as compressing plate 116 . In various embodiments, compressing plate 116 is a disc-shaped structure with a lip surrounding the outer edge that curves downward toward base 112 . Compressing plate 116 may be made of a rigid material such as galvanized steel, stainless steel, aluminum, etc., that is strong enough to compress cartridge 115 without distorting. In various embodiments, compressing plate can be formed in a shape having a convex top surface on a side facing away from the roof surface, which inhibits accumulation of rain and/or debris when mounted on the roof surface. Compressing plate 116 may include one or more retention features (e.g. recesses, openings) positioned to match with location of tabs 114 B formed on guide base 114 so that compressing plate 116 will remain mechanically coupled to the entire assembly, for ease of transport and installation. Housing of compressing plate 116 includes central opening 116 A which is co-located with opening 115 A in cartridge 115 and opening 112 A in base 112 . FIGS. 6A-6C illustrate the process of mounting an exemplary base portion assembly 110 to a roof surface using a hanger bolt 121 as the mechanical fastener. Base assembly 110 is installed by first drilling a pilot hole into a roof surface, for example, directly through any existing shingles. After the pilot hole has been drilled, base assembly 110 may be positioned over the pilot hole, as shown in FIG. 6A and hanger bolt 121 inserted through aperture 116 A in compressing plate 116 , aperture 115 A in cartridge 115 , through guide base 114 and through aperture 112 A in base 112 , and into the pilot hole. Then, using an impact driver or other tool, torque is applied to hanger bolt 121 until head 121 A engages the top surface of compressing plate 116 , which in turn begins to crush cartridge 115 . As torque is continuously applied, compressing plate 116 continued to crush cartridge 115 until the bottom of the lip of the outer periphery of compressing plate 116 rests against the top surface of base 112 . Tabs 114 A (not shown) can be deflected outward or break off as the compressing plate 116 moves downward. During this torqueing process, sealant will be forced through the openings in the bottom of guide base 114 , through apertures 113 in base 112 and underneath to seal around lag bolt 121 and any missed drill holes that are also within the void defined by base 112 and sealant ring 111 . FIGS. 7A and 7B show an exploded view and an assembled view of a photovoltaic mounting bracket 120 and base assembly 110 . In various embodiments, bracket 120 includes an opening, such as slot 124 , through which the top of lag bolt 121 passes when assembled. Nut 122 rests against top surface 123 of bracket 120 so as to hold bracket 120 against base assembly 110 . Slot 124 allows mounting bracket 120 to be rotated 360 degrees about lag bolt 121 as well as moved laterally along the primary axis of bracket 120 . Such a configuration allows for adjustment of mounting bracket as needed for a position of a photovoltaic module mounted on the roof surface. Bracket 120 can further include raised portion 125 that supports photovoltaic coupling device 130 . An advantage of this design is that raised portion 125 provides extra clearance for mounting hardware supporting PV coupling device 130 , such as, for example, nut 122 . In various embodiments, PV coupling device 130 is supported above raised portion 125 by a threaded stud such as stud 131 . An advantage of this is, is that adjustments can be made to the height of PV module coupling device 130 and base assembly 110 (and by extension between device 130 and the roof surface) to compensate for an uneven roof surface. As shown in the figures, PV module coupling device 130 can include a rock-it connector such as connector 133 manufactured by SolarCity Corp. Such a coupling device is described and illustrated, for example, in commonly assigned U.S. patent application Ser. No. 14/615,320, Publication No. 2015/0155823-A1, the disclosure of which is herein incorporated by reference in its entirety. However, it should be appreciated that a clamping or wrap-around style connector, or other types of connectors, may be utilized with various embodiments with departing from the spirit or scope of the invention. Referring now to FIGS. 8-14 , these figures show a photovoltaic module mounting system adapted to form a chemical flashing according to another embodiment of the invention. System 200 employs a somewhat different photovoltaic mounting bracket, as shown in FIGS. 1-7 , that still forms a chemical flashing that is released by the action of a hanger or lag bolt being torqued down to the roof to securely attach the base portion, in this case assembly 210 , to the roof surface. As shown in FIG. 8 , system 200 includes base assembly 210 , mounting bracket 220 and PV module coupling device 130 . Coupling device 130 is substantially the same as the coupling device shown in FIGS. 1-7 . As in the case of that embodiment, system 200 may include a clamping or wrap-around coupling device in place of rock-it connector 130 . Such variations are with in the spirit and scope of the invention. As can be understood by referring to the partly exploded view in FIG. 9 , hanger bolt 221 is inserted through base assembly 210 to secure it to the roof surface. Then, mounting bracket or foot assembly 220 is placed on top of base assembly 210 via slot 220 A. The top portion of hanger bolt 221 may pass through slot 220 A and then receives nut 222 , which is torqued down to fasten foot assembly 220 to base assembly 210 . Slot 220 A allows the location of PV module coupling device 130 to be moved with respect to hanger bolt 221 , both laterally and rotationally. After mounting is complete, the system appears as shown in FIG. 8 . FIG. 10 is a partially exploded view showing the individual components of base assembly 210 , which include, assembled from bottom to top, sealant ring 211 , base 212 , sealant guide 214 , sealant cartridge 215 and compressing plate 216 . Each of these components of base assembly 210 and their relative position is described in further detail below. Base 212 sits on top of sealant ring 211 . Base 212 is preferably made of a rigid, corrosion resistant material, for example a metal alloy, such as steel, aluminum or hard plastic. Base 212 can further include a recess on its underside (e.g., roof-facing side) that is dimensioned to receive sealant ring 211 , which helps prevent leakage of sealant out from the seam between ring 211 and base 212 . Sealant ring 211 can be made of foam or other deformable material so as to define a perimeter under base assembly 210 that contains the flowable sealant as it is extruded through any apertures 212 A in base 212 . Sealant ring 211 can also define a cavity between the bottom of base 212 and the roof surface, which defines the space in which the chemical flashing is formed. Sealant ring can be releasably or fixedly attached to the underside of base 212 by any suitable means, for example a pressure-sensitive adhesive. As shown, base 212 further includes one or more holes 212 A for receiving a mechanical faster such as a lag bolt or hanger bolt. As shown, hole 212 A is in the center, however, it should be appreciated that if more than one fastener is used, there may be multiple holes distributed around base 212 . Base 212 further includes one or more apertures 213 for guiding flow of sealant material into the void defined by sealant ring 211 , base 212 and the roof, and around the lag bolt or hanger bolt penetrating into the roof, thereby forming the chemical flashing around the roof penetration. Next, in this assembly 210 is sealant cartridge 215 and sealant carrier or guide 214 . Sealant guide 214 sits on base 212 and may include one or more coupling features, such as downward-facing tabs 214 A with distal retention features 214 D, which detachably couple guide 214 to base 212 by a mechanism the same or similar to that described in the embodiment of FIGS. 1-7 . Guide 214 can further include one or more coupling features, such as upward-facing tabs 214 B that serve to maintain the position of sealant cartridge 215 and also to connect it to compressing plate 216 by distal retention features 214 B. Compressing plate 216 can include a set of corresponding retention features, such as openings 216 A, that receive tabs retention features 214 C of tabs 214 B to keep assembly 210 together before installation. Such coupling features allows the base portion assembly 210 to remain as an assembly without any need for any additional fasteners, such as hangar bolt, extending therethrough. Though not shown in FIG. 10 , sealant cartridge 215 and guide base 214 may also include a reinforcing ring, such as described previously. Such a reinforcing ring helps keep cartridge 215 seated on guide base 214 and to prevent against blow-outs when compressing plate 216 is compressed down towards base 212 , thereby causing sealant to be dispensed through apertures 213 and under base 212 around bolt 221 and forming the chemical flashing. FIG. 11 shows another exemplary reinforcing ring 217 . Reinforcing ring 17 is preferably though not necessarily short enough to allow compressing plate 216 to compress against base 212 without interfering but tall enough to substantially prevent blow outs. Ring 217 can further include orientating and/or coupling features, such as recesses 217 A, which fit into corresponding protrusions 214 E on guide 214 . These features can be adapted to fit together in a snap-fit type coupling so as to secure retaining ring 217 A with guide 214 . Guide 214 further includes openings 214 E that align with corresponding apertures 213 in base 212 through which sealant flows from sealant cartridge 215 . Turning now to FIGS. 12A and 12B , these figures show alternative embodiments of base assembly 210 in which guide 224 and base 223 are slightly different from guide 214 and base 212 . Guide 224 includes a plurality of upward-facing tabs 224 A with distal retention features 224 A which engage corresponding retention features 226 A in compressing plate 226 . In this embodiment, compressing plate 226 has a larger diameter than compressing plate 216 , and can be made larger than sealant ring 211 so that when compressing plate 226 is compressed against cartridge 225 and guide base 224 , the outer periphery of compressing plate 226 extends further down such that it contacts ring 211 as well as the roof surface. In this embodiment, base 223 can be made out of plastic or other less durable material since most or all of base 223 may not be in the load path of the assembly 210 , unlike base 212 previously described. As shown in FIG. 12B , base 223 includes a central hole 223 A for passage of the mechanical fastener and apertures 223 B for passage of flowable sealant. Base 223 can further include one or more puncture tabs 223 T within openings 223 B for facilitating puncture of a bottom portion of sealant cartridge 225 . Puncture tabs 223 T are shown in more detail in FIG. 13 . As shown, puncture tabs 22 T include an inwardly projecting tab extending inwardly to an upward projecting barb that is elevated above base 223 when base 223 is set on the roof or other flat surface. Puncture tabs 223 T assist in the rupturing of the seal of cartridge 225 when compressing plate 226 is lagged down towards base 223 . Puncture tabs 223 T can be located at the point of apertures 223 B to further guide the flow of the sealant in cartridge 225 under base 223 . FIG. 14 illustrates two variations of the underside of base 223 - 223 B, and 223 B′—which may assist in directing and evenly distributing the flow of sealant material from cartridge 225 under base 223 . Design 223 B is a spiral design in which sealant material is guided outward spirally in an increasing large diameter path starting from the center. Design 223 B′ is a labyrinth design consisting of a series of partial rings in which sealant is simultaneously guided away from the center in three directions, converging around each ring before moving on to the next ring. These or other bottom designs may be utilized with the various embodiments of the invention. It is appreciated that base could include further variations that include channels or geometries that facilitate controlled flow of sealant through the base so as to form a consistent and uniform chemical flashing. Referring back to FIGS. 8 and 9 , mounting bracket assembly 220 may include a section of extrusion or roll formed steel that is somewhat longer than the diameter of base assembly 210 . Bracket assembly 220 may have a downward U cross-sectional shape where the bottom of each side of the U rests on a ridge or flat surface formed in the top of compressing plate 216 . It should be appreciated that this design is merely exemplary and other types of mounting brackets may be used with system 200 shown in these figures. Referring now to FIGS. 15-21 , these figures show a photovoltaic mounting system including a chemical flashing according to various embodiments of the invention. System 300 is similar to that shown in the previous embodiments in that it includes base assembly 310 , mounting bracket 220 and photovoltaic module coupling device 130 . One difference over previous embodiments, is that several of the components of base assembly 310 are combined or integrated into a single part. As can be seen in FIG. 15 and the exploded view in FIG. 16 , however, the mounting system include an integrated base assembly 310 that is integrated into a single component. Typically, base assembly 310 is integrated such that it cannot be readily disassembled by an end-user. A partly exploded view of integrated guide base 311 is shown in FIG. 17A . As can be seen, in addition to sealant ring 313 , base assembly 311 includes an integrated guide 311 and sealant reservoir 315 . In this embodiment, guide base 311 includes one or more gussets 312 to provide sufficient strength to maintain the integrity of the assembly prior to installation, yet allow directionally controlled collapse upon installation. As shown, reservoir 315 includes a center hole 316 for allowing a lag bolt, hanger bolt, or other fastener to pass through. It is appreciated however, that reservoir could be formed in a shape that would not require a central hole or could be formed of a material that would allow the mechanical fastener to puncture the reservoir when inserted therethrough. In some embodiments, reservoir 315 of guide base 311 may include seal of foil or other material on its underside to protect the sealant from the air while still allowing for easy penetration during installation. Reservoir 315 can be attached to compressing plate 320 by any suitable means. In the depicted embodiment, reservoir 315 include one more pins 317 for attaching and orienting guide 311 to compressing plate 320 . As shown in FIG. 17 , compressing plate 320 may be attached to base assembly 310 by pins 317 on the top surface of reservoir 315 which pass through reciprocal holes 320 B formed in compressing plate 320 , which also includes a central hole 320 A for passage of the mechanical fastener. Reservoir can then be secured through a process such as heat staking or ultrasonic bonding, thereby affixing pins 317 and compressing plate 320 to one another, as depicted in the detail cross-section shown at bottom of FIG. 17 . In various embodiments, the underside of reservoir 315 includes a void in which sealant is placed prior to sealing with foil seal 314 underneath that is surrounded by sealant ring 313 , as can be understood by referring to FIG. 18 . Also, guide base 311 can include multiple gussets 312 to assist in uniform deformation of ring 313 during installation. Typically, gussets 312 are defined as tapered reinforcing ribs that are distributed along an outer wall of the integrated guide base 311 . In various embodiments, the top of reservoir 315 may project higher than the walls of guide base 311 so that reservoir 315 is at least partially compressed by compressing plate 320 before compressing plate 320 engages the top of the remainder of guide base 311 . Installation of system 300 is similar to that shown in other embodiments. A hanger bolt, lag bolt or other fastener is driven into the roof through base assembly 310 . Compressing plate 320 first engages the top of reservoir 315 of guide base 311 and then the top edge of base 311 . Continued torqueing of fastener 221 eventually causes compressing plate 320 to compress reservoir 315 and guide base 311 until reservoir 315 is fully compressed. An example of such a configuration is shown in FIG. 19A-C , which illustrates sequential cross-sectional views before, during and after mounting into the roof surface, respectively. In FIG. 19A , the top of reservoir 315 can be seen extending above the walls of guide 315 . In FIG. 19B , compressing plate 320 has partly compressed reservoir 215 and abutted against the top of the walls of guide 215 . In FIG. 19C , compressing plate 320 has been torqued into the roof surface to entirely compress reservoir 315 and abut against sealant ring 313 and roof surface, thereby extruding the flowable sealant into the space between the base and roof surface to form a chemical flashing along where the bolt 221 penetrates the roof surface. As shown in FIGS. 20 and 21A-21B , guide base 311 can further include one or more vents 318 that allow sealant to flow back up under housing 320 rather than being forced out of the sides around ring 313 . These vents 318 helps prevent any excess sealant from flowing onto the roof surface. The guide base 311 can further include the labyrinth of open channels that facilitate controlled flow of sealant between guide base 311 and the roof surface. FIG. 20 shows a detailed view of the underside of guide base 311 . In various embodiments, this may include a chamber or void centered on a lag or hanger bolt opening. In addition, there may be a labyrinth 311 A or other pattern or network of open channels to further guide the flow of sealant under guide base 311 , eventually reaching vent holes 318 which can direct excess sealant back under compressing plate 320 to help prevent blow-outs through the side of ring 313 . FIG. 21A shows a detailed cross-sectional view of the sealant flow path (indicated by arrows) as the sealant flow through the labyrinth of channels and excess sealant flows through vent opening 318 into a space between guide base 311 and bell-shaped compressing plate 320 . FIG. 21B shows an underside detailed view indicating a sealant flow path through the labyrinth of channels 311 A towards vent openings 318 towards the outer periphery of guide base 311 . Referring now to FIGS. 22-26 , these figures illustrate a photovoltaic mounting system adapted to form a chemical flashing according to yet another embodiment of the invention. As shown in the assembled view of FIG. 22 and can be understood further in the exploded view of FIG. 23 , system 400 includes base assembly 410 , mounting bracket 220 , and photovoltaic module coupling device 130 . Elements 220 and 130 are substantially the same or similar to those shown in previous embodiments, such that any previous detailed description can apply also to this embodiment. Base assembly 410 includes compressing plate 420 , sealing ring 411 , sealant cartridge 415 and an integrated guide base 414 that acts as both as a guide for supporting the sealant cartridge as well as a base for placing against the roof surface. An exploded view of base assembly 410 can be seen in FIG. 24A and an assembled view is shown in FIG. 24B . FIGS. 25A-25B and 26 show integrated guide base 414 in greater detail, FIG. 25A illustrating a top side perspective view, FIG. 25B illustrated a bottom roof-facing side perspective view and FIG. 26 illustrating a cross-sectional side view. Guide base 414 includes substantially planar front surface 414 F and bottom, roof-facing surface 414 B. As shown, roof-facing surface 414 B includes multiple columns or legs 414 L that support assembly 414 and maintain a space during installation in which sealant can flow freely around the hanger bolt and under guide base 414 . Guide base 414 also includes an a central opening 414 A for passage of the fastener, such as a hanger bolt or lag bolt, while allowing contact with the sealant material. A continuous aperture 414 C surrounds the central opening 414 A to allow flowable sealant to flow continuously about the fastener so that the chemical flashing forms is sealed around the mechanical fastener. One or more puncturing tabs 414 T can be included to quickly and evenly rupture any seal on the bottom side of sealant cartridge 415 when sealant cartridge 415 is compressed against guide 414 during installation. As can be seen in FIG. 26 , the bottom of puncture tabs 414 T extend below the bottom of the spacer columns 414 L such that when guide base 414 is pressed against the roof surface, puncture tabs 414 T are pivoted upwards thereby puncturing a breakable seal on the bottom, roof-facing side of sealant cartridge 415 . Guide base 414 may also include one or more vertical tabs around its perimeter and/or coupling features 414 G that interface with an outer lip along the bottom of sealant cartridge 415 to hold sealant cartridge 415 in place both during transit and installation. It is appreciated that any of the above described features can be used separately from the other features described or can be incorporated into any of the other embodiments described herein. As with sealant cartridge 315 , sealant cartridge 415 may include center hole 416 and multiple pins 417 that can mate with reciprocal openings in compressing plate 420 and can be attached by various means, such as heat staking or another suitable bonding process. These features enable base assembly 410 to be shipped as a single integrated product. Sealant ring 411 may be adhered to the under side (e.g., roof-facing side) of compressing plate 420 using glue or other adhesive so that when compressing plate is compressed toward the roof during installation, sealant ring 411 creates a perimeter around guide base 414 to contain the flow of sealant under base assembly 410 . The embodiments of the present inventions are not to be limited in scope by the specific embodiments described herein. For example, although many of the embodiments disclosed herein have been described with reference to composite shingle roofs, the principles herein may be equally applicable to other types of roofs. Indeed, various modifications of the embodiments of the present inventions, in addition to those described herein, will be apparent to those of ordinary skill in the art from the foregoing description and accompanying drawings and claims. Thus, such modifications are intended to fall within the scope of this invention. Further, although some of the embodiments of the present invention have been described herein in the context of a particular implementation in a particular environment for a particular purpose, those of ordinary skill in the art will recognize that its usefulness is not limited thereto and that the embodiments of the present inventions can be beneficially implemented in any number of environments for any number of purposes. Accordingly, this disclosure should be construed in view of the full breath and spirit of the embodiments of the present inventions as disclosed herein and claimed below.

Photovoltaic mounting systems that form chemical flashings are provided herein. Such sealant injection systems provide directional control and containment of sealant flow to form a chemical flashing that improves sealing of roof penetrations. Such systems can include a base assembly adapted to mount to a roof surface and support a mounting bracket having a photovoltaic module coupling device. The base assembly can include a sealant guide, a compressing plate and a sealant cartridge held between the guide and compressing plate by one or more coupling features of the guide. The coupling features can include a first set of features, such as a series of tabs, that facilitate coupling between the guide and the compressing plate. The base assembly can further include a base that releasably couples to the sealant guide by a second set of coupling features. Methods of mounting such base assemblies on roof surfaces are also provided.

CROSS REFERENCE TO RELATED APPLICATION [0001] This application claims the benefit of U.S. Provisional application Ser. No. 60/581,542 (Case 9678P), filed on Jun. 21, 2004. FIELD [0002] The present invention relates to a method of determining performance of anhydrous antiperspirant compositions suitable for topical application to human skin, particularly the axilla. BACKGROUND [0003] There are many types of antiperspirant compositions that are commercially available or otherwise known in the antiperspirant art. These products typically contain an antiperspirant active, e.g. zirconium or aluminum salts or combinations thereof, solubilized or dispersed in a suitable liquid carrier, and sufficient structurants to produce the desired solid form in cases of sticks and the desired rheological character in cases of creams. [0004] Antiperspirant compositions are designed to provide effective perspiration and odor control while also being cosmetically acceptable during and after application onto the underarm area of the skin. However, the need still exists for a method of determining performance of anhydrous antiperspirant compositions. SUMMARY [0005] The present invention relates to a method of determining performance of anhydrous antiperspirant compositions comprising an antiperspirant active, a liquid carrier, and a structurant. The compositions, processes, and methods of the present invention provide enhanced antiperspirant performance. DETAILED DESCRIPTION [0006] While the specification concludes with the claims particularly pointing and distinctly claiming the invention, it is believed that the present invention will be better understood from the following description. [0007] The present invention relates to a method to evaluate the performance of antiperspirant compositions. It has been found that compositions that develop higher red values, that is, a higher a-value on a standard L-a-b colorimetric measurement as detailed below, are better performing products. Also, several formulas have been developed that combine the key ingredients of an antiperspirant active, suitable liquid carrier, and suitable structurant with the appropriate making process to achieve the desired high performing value of greater than 2.00 a-value on the disclosed performance test. [0008] All percentages, parts and ratios are based upon the total weight of the antiperspirant compositions of the present invention and all measurements made are at 25° C., unless otherwise specified. All such weights as they pertain to listed ingredients are based on the active level and, therefore, do not include carriers or by-products that may be included in commercially available materials, unless otherwise specified. [0009] As used herein, the term “antiperspirant compositions” are those compositions that are applied in a thin film to the axilla area in order to reduce or eliminate underarm perspiration. Products contemplated by the phrase “antiperspirant composition” include, but are not limited to, liquids (e.g., aerosols, pump sprays, roll-ons), solids (e.g., gel solids, invisible solids, wax solid sticks), semi-solids (e.g. creams, soft solids, lotions), and the like, provided that the selected form contains all the essential elements as defined [0010] The term “ambient conditions,” as used herein, refers to surrounding conditions under about one atmosphere of pressure, at about 50% relative humidity, and at about 2° C., unless otherwise specified. [0011] The term “anhydrous” as used herein means that the antiperspirant stick composition of the present invention, and the essential or optional components thereof, are substantially free of added or free water. From a formulation standpoint, this means that the anhydrous antiperspirant stick compositions of the present invention contain less than about 1%, and more specifically zero percent, by weight of free or added water, other than the water of hydration typically associated with the particulate antiperspirant active prior to formulation. [0012] The term “structurant”, as used herein, means any material known or otherwise effective in providing suspending, gelling, viscosifying, solidifying and/or thickening properties to the composition, or those materials which otherwise provide structure to the final product form. These solid structurants include one or more solid crystalline or other nonpolymeric suspending agents suitable for topical application to human skin. Suitable suspending agents are those that can form in the composition a crystalline or other matrix within which volatile solvents, non-volatile solvents, or other liquid components of the composition are contained. Such materials will typically be solids under ambient conditions and include organic solids, waxes, crystalline or other gellants, or combinations thereof. A structurant provides a uniform distribution of the particulate active throughout the product and also controls product hardness or rheology. [0013] The term “particulate,” as used herein, refers to compositions or materials that are comprised of solid particles and are not dissolved in water or other solvents. [0014] The term “volatile,” as used herein, unless otherwise specified, refers to those materials that are liquid under ambient conditions and which have a measurable vapor pressure at 25° C. These materials typically have a vapor pressure greater than about 0.01 mmHg, more typically from about 0.02 mmHg to about 20 mmHg, and an average boiling point typically less than about 250° C., more typically less than about 235° C. [0015] The term “cosmetically acceptable”, as used herein, means that the product glides on smoothly during application, is non-irritating, and results in little or no visible residue (e.g., low residue performance) after application to the skin. [0000] I. Composition [0016] A. Antiperspirant Active [0017] The antiperspirant compositions of the present invention comprise a particulate antiperspirant active suitable for application to human skin. The concentration of antiperspirant active in the composition should be sufficient to provide the desired perspiration and odor control from the antiperspirant stick formulation selected. [0018] The anhydrous antiperspirant stick compositions of the present invention comprise an antiperspirant active at concentrations of from about 0.5% to about 60%, and more preferably from about 5% to about 35%, by weight of the composition. These weight percentages are calculated on an anhydrous metal salt basis exclusive of water and any complexing agents such as, for example, glycine and glycine salts. The antiperspirant active as formulated in the composition are in the form of dispersed particulate solids having a preferred average particle size or equivalent diameter of less than about 100 microns, more preferably less than about 20 microns, and even more preferably less than about 10 microns. [0019] The antiperspirant active for use in the anhydrous antiperspirant compositions of the present invention may include any compound, composition or other material having antiperspirant activity. More specifically, the antiperspirant actives may include astringent metallic salts, especially inorganic and organic salts of aluminum, zirconium and zinc, as well as mixtures thereof. Even more specifically, the antiperspirant actives may include aluminum-containing and/or zirconium-containing salts or materials, such as, for example, aluminum halides, aluminum chlorohydrate, aluminum hydroxyhalides, zirconyl oxyhalides, zirconyl hydroxyhalides, and mixtures thereof. [0020] 1. Aluminum Salts [0021] Aluminum salts useful in the present invention include those that conform to the formula: Al 2 (OH) a Cl b ·x H 2 O [0022] wherein a is from about 2 to about 5; the sum of a and b is about 6; x is from about 1 to about 6; and a, b, and x may have non-integer values. Particularly preferred are the aluminum chlorohydroxides referred to as “5/6 basic chlorohydroxide”, wherein a=5, and “⅔ basic chlorohydroxide”, wherein a=4. [0023] Processes for preparing aluminum salts are disclosed in U.S. Pat. No. 3,887,692, Gilman, issued Jun. 3, 1975; U.S. Pat. No. 3,904,741, Jones et al., issued Sep. 9, 1975; U.S. Pat. No. 4,359,456, Gosling et al., issued Nov. 16, 1982; and British Patent Specification 2,048,229, Fitzgerald et al., published Dec. 10, 1980. Mixtures of aluminum salts are described in British Patent Specification 1,347,950, Shin et al., published Feb. 27, 1974. [0024] 2. Zirconium Salts [0025] Preferred zirconium salts for use in the present invention include those which conform to the formula: ZrO(OH) 2-a Cl a ·x H 2 O [0026] wherein a is from about 1.5 to about 1.87; x is from about 1 to about 7; and a and x may both have non-integer values. [0027] These zirconium salts are described in Belgian Patent 825,146, Schmitz, issued Aug. 4, 1975. Preferred zirconium salts are those complexes that additionally contain aluminum and glycine, commonly known as “ZAG complexes”. These ZAG complexes contain aluminum chlorohydroxide and zirconyl hydroxy chloride conforming to the above-described formulas. Such ZAG complexes are described in U.S. Pat. No. 3,679,068, Luedders et al., issued Feb. 12, 1974; Great Britain Patent Application 2,144,992, Callaghan et al., published Mar. 20, 1985; and U.S. Pat. No. 4,120,948, Shelton, issued Oct. 17, 1978. [0028] B. Anhydrous Liquid Carriers [0029] The antiperspirant compositions of the present invention may comprise an anhydrous liquid carrier at concentrations ranging from about 10% to about 90%, preferably from about 20% to about 80%, more preferably from about 30% to about 70 %, by weight of the composition. Such concentrations will vary depending upon variables such as product form, desired product hardness, selection of other ingredients in the composition, and so forth. The anhydrous liquid carrier for use in the composition can be any anhydrous liquid that is known for use in personal care applications or is otherwise suitable for topical application to the skin. Preferred anhydrous liquid carriers include both volatile fluids and nonvolatile fluids. [0030] 1. Volatile Fluid [0031] The antiperspirant composition of the present invention may further comprise a volatile fluid, preferably a volatile silicone carrier at concentrations ranging from about 20% to about 80%, and more specifically from about 30% to about 60%, by weight of the composition. The volatile silicone of the solvent may be cyclic, linear, and/or branched chain silicone. “Volatile silicone”, as used herein, refers to those silicone materials that have measurable vapor pressure under ambient conditions. Non-limiting examples of suitable volatile silicones are described in Todd et al., “Volatile Silicone Fluids for Cosmetics”, Cosmetics and Toiletries, 91:27-32 (1976). [0032] The volatile silicone is preferably a cyclic silicone having from about 3 to about 7 silicone atoms, and more preferably from about 5 to about 6, and still more preferably about 5 silicone atoms. Preferred are those which conform to the formula: [0033] wherein n is from about 3 to about 7, preferably from about 5 to about 6, more preferably about 5. These volatile cyclic silicones generally have a viscosity of less than about 10 centistokes at 25° C. Suitable volatile silicones for use herein include, but are not limited to, Cyclomethicone D5 (commercially available from G. E. Silicones); Dow Corning 344, and Dow Corning 345 (commercially available from Dow Corning Corp.); and GE 7207, GE 7158 and Silicone Fluids SF-1202 and SF-1173 (available from General Electric Co.). SWS-03314, SWS-03400, F-222, F-223, F-250, F-251 (available from SWS Silicones Corp.); Volatile Silicones 7158, 7207, 7349 (available from Union Carbide); Masil SF-V (available from Mazer) and combinations thereof. [0034] 2. Non-Volatile Fluid [0035] The antiperspirant composition of the present invention may further comprise a non-volatile fluid. These non-volatile fluids may be either non-volatile organic fluids or non-volatile silicone fluids. a. Non-Volatile Organic Fluids [0037] The antiperspirant composition of the present invention may further comprise non-volatile organic fluids. The non-volatile organic fluid can be present at concentrations ranging from about 1% to about 20%, and more preferably from about 2% to about 15%, by weight of the composition. [0038] Non-limiting examples of nonvolatile organic fluids include mineral oil, PPG-14 butyl ether, isopropyl myristate, petrolatum, butyl stearate, cetyl octanoate, butyl myristate, myristyl myristate, C12-15 alkylbenzoate (e.g., Finsolv.™.), dipropylene glycol dibenzoate, PPG-15 stearyl ether benzoate and blends thereof (e.g. Finsolv TPP), neopentyl glycol diheptanoate ( e.g. Lexfeel 7 supplied by Inolex), octyldodecanol, isostearyl isostearate, octododecyl benzoate, isostearyl lactate, isostearyl palmitate, isononyl/isononoate, isoeicosane, octyldodecyl neopentanate, hydrogenated polyisobutane, and isobutyl stearate. Many such other carrier liquids are disclosed in U.S. Pat. No. 6,013,248 (Luebbe et al.) and U.S. Pat. No. 5,968,489 (Swaile et al). [0039] b. Nonvolatile Silicone Fluids [0040] The antiperspirant compositions of the present invention may further comprise a non-volatile silicone fluid. The non-volatile silicone fluid is preferably a liquid at or below human skin temperature, or otherwise in liquid form within the anhydrous antiperspirant composition during or shortly after topical application. The concentration of the non-volatile silicone is from about 1% to about 15%, more preferably from about 2% to about 10%, by weight of the composition. Preferred are those nonvolatile silicone fluids which conform to the formula: [0041] wherein n is greater than or equal to 1. These linear silicone materials will generally have viscosity values of from about 10 centistokes to about 100,000 centistoke, preferably less than about 500 centistoke, more preferably from about 5 centistoke to about 200 centistoke, even more preferably from about 10 centistoke to about 50 centistoke, as measured under ambient conditions. [0042] Specific non limiting examples of suitable nonvolatile silicone fluids include Dow Corning 200, hexamethyldisiloxane, Dow Corning 225, Dow Corning 1732, Dow Corning 5732, Dow Corning 5750 (available from Dow Corning Corp.); and SF-96, SF-1066 and SF18(350) Silicone Fluids (available from G.E. Silicones). [0043] Preferably, the low surface tension non-volatile solvent is selected from the group consisting of dimethicones, dimethicone copolyols, phenyl trimethicones, alkyl dimethicones, alkyl methicones, and mixtures thereof. [0044] C. Structurants [0045] The antiperspirant compositions of the present invention contain a structurant. The structurant may be present in an amount of from about 0.01% to about 25%, more preferably from about 1% to about 15%, even more preferably from about 2.0% to about 10%. [0046] The structurant can be selected from the group consisting of petroleum wax, such as ozokerite or ceresin, stearyl alcohol and other fatty alcohols; hydrogenated castor oil; beeswax; camauba; candelilla; spermeceti wax; baysberry; synthetic waxes, such as Fisher-Tropsch waxes and non-petroleum based microcrystalline wax; polyethylenes with a molecular weight of from about 200 to about 1000 daltons; suitable fatty acid esters such as Syncrowax ERL-C available from Croda, solid triglycerides such as Syncrowax HRC and HGL-C from Croda; and any combination and mixtures thereof. Other non-limiting examples of structurants suitable for use herein are described in U.S. Pat. No. 5,976,514 (Guskey et al.) and U.S. Pat. No. 5,891,424 (Bretzler et al.). [0047] D. Optional Ingredients [0048] The antiperspirant compositions of the present invention may further comprise any optional material that is known for use in antiperspirant and deodorant compositions or other personal care products, or which is otherwise suitable for topical application to human skin. Nonlimiting examples of optional materials include dyes or colorants, emulsifiers, perfumes, distributing agents, antimicrobials, deodorant perfumes, pharmaceutical or other topical actives, preservatives, surfactants, processing aides such as viscosity modifiers, wash-off aids, and so forth. Examples of such optional materials are described in U.S. Pat. No. 4,049,792 (Elsnau); U.S. Pat. No. 5,019,375 (Tanner et al.); and U.S. Pat. No. 5,429,816 (Hofrichter et al.). [0000] II. Process [0049] The antiperspirant compositions of the present invention may be prepared by any known or otherwise effective technique, suitable for providing an anhydrous composition of the desired form and having the essential materials described herein. Many such techniques are described in the antiperspirant/deodorant formulation arts for the described product forms. [0050] For example, the antiperspirant stick compositions can be formulated by mixing the volatile silicone and nonvolatile fluid materials under ambient conditions, or under conditions sufficient to render the admixture fluid or liquid, and then adding the structurants to the mixture and heating the resulting mixture sufficiently to liquefy the added structurants, e.g., at approximately 85° C. for many wax solids, to form a single phase liquid. Antiperspirant solids can then be added to and dispersed throughout the heated, single-phase liquid before allowing the resulting combination to cool to approximately 78° C., at which point perfumes and similar other materials (if any) can be mixed into the combination. The combination can then be cooled to just above the solidification point of the suspending agent (e.g., typically about 60° C.), deposited into dispensing packages, and allowed to solidify under ambient conditions. [0000] III. Test Method [0051] The test method used to determine performance of the antiperspirant product is described below. [0052] A. Preparation of Starting Solutions: [0053] Phenol Red/Deionized Water solution (Deionized Water, 99.985% per weight; Phenol Red, 0.015% per weight) can be prepared as follows: Add Phenol Red powder to deionized water at room temperature. Stir for approximately 2 minutes at approximately 500 rpm, or until the powdered phenol red is completely dissolved into solution, using a magnetic stir bar and stir plate. [0054] Potassium Hydroxide/Deionized Water solution (Deionized Water, 95% per weight; Potassium Hydroxide (solid), 5% per weight) can be prepared as follows: Add Potassium Hydroxide pellets to deionized water at room temperature. Stir for approximately 1 minute at approximately 500 rpm, or until the potassium hydroxide is completely dissolved into solution, using magnetic astir bar and stir plate. [0055] B. Preparation of pH-Indicator Solution: [0056] The pH-indicator solution can be prepared as follows: Weigh 200 grams of above Phenol Red/Deionized Water solution into a glass beaker. At ambient conditions, stir solution continuously at 100 rpm using a magnetic stir bar and stir plate. Insert calibrated pH probe, such as the Orion 8102BNV from Ross, into the solution. Measure pH continuously. Adjust pH of Phenol Red/Deionized Water solution to 10.00+/−0.05 by adding 1 ml increments of Potassium Hydroxide/Deionized Water solution to the beaker containing the phenol red/deionized water solution while continually stirring. [0057] C. Preparation of Antiperspirant Sample: [0058] A film of the antiperspirant sample can be prepared using the following procedure. BYTAC TYPE VF-81 chemical resistant Norton FEP film is cut into 3×7 cm rectangles. A circle 2.2 cm in diameter is punched out. The protective back layer of the film is removed and the sticky side of the BYTAC film is adhered to a standard glass microscope slide. Care is taken such that the 2.2 cm circle cut out of the middle of the film is completely on the microscope slide. Antiperspirant is applied on the microscope slide in the center of the circle cut out of the BYTAC film. The antiperspirant sample is thoroughly spread throughout the circle by using a spatula or equivalent in a back and forth motion across the film surrounding the cut out circle. Spreading is continued until a smooth surface of antiperspirant product across the entire cut out circle is achieved. Carefully remove the BYTAC film from the microscope slide leaving behind the smooth, antiperspirant film. The antiperspirant film on the microscope slide is circular with a thickness equal to the thickness of the just removed BYTAC film (˜0.1778 mm). [0059] D. Application of ph Solution: [0060] The antiperspirant film on the microscope slide is dried for about 24 hours at ambient conditions (first drying period). After the drying period, 20.0 microliters of the phenol red pH-indicator solution are applied to the center of the dried, antiperspirant sample using a standard micropipette such as the 5-50 microliter adjustable Finnpipette from Thermo Labsystems. The sample with the applied 20.0 microliters of phenol red ph indicator solution is left to dry for about 24 hours at ambient conditions (second drying period). [0061] E. Data Collection and Analysis: [0062] After this second 24 hour drying period, the microscope slide with the dried antiperspirant film is placed face up on an approximate 15.24 cm×15.24 cm sample of black felt. A metal ring (1.8 cm diameter×2.5 cm height) is placed on the dried sample eliminating possible contamination of measurements by outside light sources. Care is taken to ensure the dried circle on phenol red ph solution is located in the center of the metal ring. A calibrated Minolta CR-300 series colorimeter, or equivalent, is placed on top of the metal ring. A standard spectral photometric measurement is taken and converted into standard L-a-b scale readings. At least four measurements are taken per sample. The average of the several (at least four) a-value readings is reported. [0063] Preferred anhydrous antiperspirant compositions have an a-value measurement of at least about 2.0, more preferably at least about 2.1, even more preferably, at least about 2.2. [0000] IV. Product Form [0064] The antiperspirant compositions of the present invention can be formulated as any known or otherwise effective product form for providing topical application of antiperspirant or deodorant active to the desired area of the skin. Non-limiting examples of such product forms include liquids (e.g., aerosols, pump sprays, roll-ons), solids (e.g., gel solids, invisible solids, wax solid sticks), semi-solids (e.g. creams, soft solids, lotions), and the like, provided that the selected form contains all the essential elements as defined herein. Preferably, the antiperspirant compositions of the present invention are semi-solids or solids. [0065] The antiperspirant products are generally stored in and dispensed from a suitable package or applicator device, such as a cream dispenser with perforated application domes, etc. These packages should be sufficiently closed to prevent excessive loss of volatiles prior to application. [0000] V. Method of Use [0066] The antiperspirant compositions of the present invention may be applied topically to the underarm or other suitable area of the skin in an amount effective to reduce or inhibit perspiration. Preferably, compositions of the present invention are applied in an amount ranging from at least about 0.1 gram to no more than about 20 grams, preferably no more than about 10 grams, more preferably no more than about 2 grams per axilla. [0067] The composition is preferably applied to the underarm at least about one or two times daily, preferably once daily, to achieve effective antiperspirant reduction or inhibition over an extended period. The antiperspirant composition can also be applied every other day, or every third or fourth day, and then optionally to supplement application on off-days with other personal care products such as deodorants and/or conventional antiperspirant formulations. [0068] Compositions of the present invention are preferably applied to skin, wherein the anhydrous liquid carrier leaves behind a skin-adhering and active-containing film. This film is positioned over the sweat ducts and resists flaking and/or rub-off, thereby being present through multiple perspiration episodes. [0000] VI. Competitive Products [0069] Numerous commercially available antiperspirant products were tested using the above disclosed performance method. The product along with the measured a-value is reported below. Product a-value Old Spice Red Zone Soft Solid 1.81 Old Spice High Endurance Invisible Solid 1.45 Old Spice Red Zone Invisible Solid 1.91 Secret Platinum Soft Solid 1.8 Secret Platinum Invisible Solid 1.54 Secret Skin Renewal Invisible Solid 1.31 Secret Shear Dry 1.55 Speedstick 24/7 IS 1.89 Axe IS 1.4 Dove IS Old Formula 1.33 Dove IS New Formula 1.62 Dove White Solid Old Formula 1.15 Dove White Solid New Formula 1.59 Gillette Powerstripe IS 1.04 Rexona Ultra SS 1.27 Ban IS 1.89 Ban SS 0.65 Degree IS 1.36 Degree SS Tri 1.17 Degree SS Tetra 1.6 Suave IS 1.26 Suave SS 1.47 Arm & Hammer IS 1.6 Arrid Total IS 0.96 Arrid Total SS 0.84 Mitchum SS 0.8 Adidas IS 0.95 Right Guard Powerstripe IS 1.34 Lady Speedstick IS 1.4 EXAMPLES [0070] The following examples further describe and demonstrate embodiments within the scope of the present invention. The examples are given solely for the purpose of illustration and are not to be construed as limitations of the present invention, as many variations thereof are possible without departing from the spirit and scope of the invention. The following examples contain a particulate antiperspirant active, a liquid solvent, and a structurant utilizing a method of preparation as detailed above. These compositions are evaluated with the disclosed performance test and have the following results: 1 2 3 4 5 6 wt. % wt. % wt. % wt. % wt. % wt. % Aluminum Zirconium 25.25 25.25 25.25 Trichlorohydrex Aluminum Zirconium 25.25 25.25 25.25 Tetrachlorohydrex Cyclomethicone 36 53.75 52.25 57.25 52.75 60.5 Dimethicone 5 5 5 5 5 5 Ozokerite Wax 13 14 14.5 Syncrowax ERL-C 1 0.5 Petrolatum 5 2 2 2 3 Stearyl Alcohol 1 1.5 0.5 Polyethylene 5 8 Glycerol 7.5 5 Tribehenate Hydrogenated 7.5 Soybean Oil Syncrowax HGL-C 3.75 1.25 Mineral Oil 5 3 Performance 2.04 2.09 2.09 2.2 2.31 2.43 Test a-value EXAMPLES 1-6 [0071] All documents cited in the Background, Summary of the Invention, and Detailed Description of the Invention are, in relevant part, incorporated herein by reference; the citation of any document is not to be construed as an admission that it is prior art with respect to the present invention. [0072] While particular embodiments of the present invention have been illustrated and described, it would be obvious to those skilled in the art that various other changes and modifications can be made without departing from the spirit and scope of the invention. It is therefore intended to cover in the appended claims all such changes and modifications that are within the scope of this invention.

A method of determining performance of anhydrous antiperspirant compositions comprising an antiperspirant active, a liquid carrier, and a structurant. The compositions, processes, and methods of the present invention provide enhanced antiperspirant performance.

BACKGROUND OF THE INVENTION [0001] (1) Field of the Invention [0002] The present invention relates generally to semiconductor integrated circuit technology and more particularly to split gate memory cells used in flash EPROMs (Electrically Erasable Programmable Read Only Memory). [0003] (2) Description of Prior Art [0004] Increased performance in computers is often directly related to a higher level of circuit integration. Tolerances play an important role in the ability to shrink dimensions on a chip. Self-alignment of components in a device serves to reduce tolerances and thus improve the packing density of chips. Other techniques can be important in shrinking device size. A method is disclosed later in the embodiments of the present invention of forming a structure with self-aligned bit line contact to word line through which a significant reduction in the area of the split gate flash cell is possible. [0005] As is well known in the art, split gate flash cells have bit lines and word lines and bit contacts that connect bit lines to drain regions. Bit lines and bit contacts are insulated from the word lines by an interlevel dielectric layer. The separation between bit contacts and word lines must be maintained large enough so as to avoid possible shorts that could develop between adjacent bit contacts and word lines. Bit contact to word line separations are determined by the positions of bit contact openings, which are set by a design rule. In arriving at the design rule the possibility of misalignment must be taken into account, which results in a required separation well beyond that needed to avoid development of shorts. This requirement for increased separation, arising from the need to account for unavoidable misalignment, limits the ability to decrease cell size. Self-alignment of the bit contact to the word line, as in the structures disclosed by the present invention, eliminates the reliability issue, allows a reduction in cell area and facilitates shrinking the cell size. [0006] A traditional method of fabricating a split gate flash memory ceil is presented in FIGS. 1 a - 1 g , where top views of the cell are presented at successive stages of the process and in FIGS. 2 a - 2 g , which show the corresponding cross-sections. A floating gate oxide, 6 , is formed on a semiconductor substrate, 2 , which preferably is a silicon substrate, to a thickness of about 80 Angstroms, followed by deposition of a poly 1 layer, 8 , to a depth of about 800 Angstroms. Active regions, 10 , are defined using isolating regions, such as shallow trench isolation regions, 4 . This is followed by deposition of a nitride layer, which preferably is a silicon nitride layer to a depth of about 2500 Angstroms. A photoresist layer, 14 , is then formed as shown in FIGS. 1 b and 2 b. The photoresist pattern, 14 , is used in etching the silicon nitride layer to achieve the shape of region 12 of FIG. 2 b. It is advantages to perform a poly 1 etch so as to achieve the shape of region 8 as shown in FIG. 2 b. Details of the method to fabricate such sharp poly tips are presented in U.S. Pat. No. 6,090,668 to Lin et al., which is herein incorporated by reference. Such sharp poly tips are advantageous because they provide enhanced erase speed. After removal of the photoresist, an oxide 2 layer, 16 , is deposited to a thickness of about 3000 Angstroms and a CMP (chemical-mechanical polishing) step is performed. A second photoresist layer, 18 , is formed and used in successively etching the silicon nitride layer and the poly 1 layer to achieve the structure shown in FIGS. 1 c and 2 c. Source regions 20 are formed by a P ion implantation at energy of about 20 keV and to a dose of about 4E14 per cm2. Removal of the second photoresist layer is followed by deposition of an oxide 3 layer to a depth of about 500 Angstroms, which enhances the lateral diffusion of the source implant. An oxide 3 etching step is performed to achieve oxide 3 spacers, 22 . A polysilicon deposition is performed to a depth of about 3000 Angstroms and a CPM step on this layer produces a poly 2 region 24 , which serves to contact the source 20 . At this stage the structure is as depicted in FIGS. 1 d and 2 d. The traditional method proceeds with oxidation of poly 2 , 24 , to form about 200 Angstroms of oxide 4 , 26 . Next the nitride layer 12 is removed, and successive etches are performed of the poly 1 layer, 8 , and floating gate oxide 1 layer, 6 . After a poly 3 deposition, 30 , to about 2000 Angstroms, the structure is as shown in FIGS. 1 e and 2 e. Etching the poly 3 layer, poly spacers, 30 , are formed that serve as word lines. A drain implant is now performed that usually is an As implant at energy about 60 keV and to a dose of about 4E15 per cm2. This forms the drain regions 36 . An interlevel dielectric (ILD) layer, 38 is deposited. A photoresist layer is formed and patterned so that upon etching of the IDL layer, contacts are opened to the drain regions. A metal 1 deposition follows removal of the photoresist layer. Another photoresist layer is formed and patterned so that after etching metal 1 bit lines 34 are formed connecting to the drain regions, 36 through the metal 1 contact regions 32 . This completes the formation of a traditional split gate flash cell, which is shown in FIGS. 1 g and 2 g. [0007] Bit lines, 34 and bit contacts, 32 are insulated from the word lines, 30 by an interlevel dielectric layer, 38 . The minimum separation, 40 , is between bit contacts and word lines and this separation must be maintained large enough so as to avoid possible shorts that could develop between adjacent bit contacts and word lines. Bit contact to word line separations are determined by the positions of bit contact openings relative to word lines and the dimensions of the openings, which are set by design rules. In arriving at the design rule the possibility of misalignment and variability in the production of contact openings must be taken into account, which results in a required minimum separation well beyond that needed to avoid development of shorts. This requirement for increased separation limits the ability to decrease cell size. Self-alignment of the bit contact to the word line, as in the structures disclosed by the present invention, eliminates the reliability issue, allows a reduction in cell area and facilitates slinking the cell size. [0008] A split-gate flash memory cell having self-aligned source and floating gate self aligned to control gate, is disclosed in U.S. Pat. No. 6,228,695 to Hsieh et al. In U.S. Pat. No. 6,211,012 to Lee et al. there is disclosed an ETOX flash memory cell utilizing self aligned processes for forming source lines and landing pads to drain regions. In U.S. Pat. No. 5,479,591 to Lin et al. there is disclosed a raised-bitline contactless flash memory cell. A method for fabricating a split-gate EPROM cell utilizing stacked etch techniques is provided in U.S. Pat. No. 5,091,327 to Bergemont. SUMMARY OF THE INVENTION [0009] It is a primary objective of the invention to provide a split gate flash cell with self-aligned bit contact to word line. It is also a primary objective of the invention to provide a method of forming a split gate flash cell with self-aligned bit contact to word line through which a significant reduction in the split-gate flash cell area is possible.** As is well known in the art, a split-gate flash memory cell normally has source and drain regions that are contacted by utilizing poly plugs. Insulating layers are required as spacers to separate these poly plugs from the floating gates and control gates of the cell, and this uses up area. Furthermore, because of the high voltages required in the erase operation the spacer width cannot be decreased without paying a penalty in reduced reliability. Elimination of the poly plugs, as in the method disclosed by the present invention, eliminates the reliability issue, allows a reduction in cell area and facilitates shrinking the cell size. Instead of poly plugs, a new self-aligned source/drain oxide etching procedure enables the formation of source/drain regions that are connected in rows directly within the silicon. This procedure of connecting source/drains is generally applicable to arrays of MOSFET-like devices. BRIEF DESCRIPTION OF THE DRAWINGS [0010] In the accompanying drawing forming a material part of this description, there is shown: [0011] FIGS. 1 a - 1 g show top views depicting a traditional method of forming split gate flash memory cells. [0012] FIGS. 2 a - 2 g show cross sectional views depicting a traditional method of forming split gate flash memory cells. [0013] FIGS. 3 a - 3 j show top views depicting a method of forming split gate flash memory cells according to the invention. [0014] FIGS. 4 a - 4 j show cross sectional views depicting a method of forming split gate flash memory cells according to the invention. DESCRIPTION OF THE PREFERRED EMBODIMENTS [0015] Preferred embodiments of the invention are well described with the aid of FIGS. 3 a - 3 j and 4 a - 4 j . A method of fabricating a novel split gate flash memory cell is presented in FIGS. 3 a - 6 j , where top views of the cell are presented at successive stages of the process and in FIGS. 4 a - 4 j , which show the corresponding cross-sections. A floating gate oxide, 6 , is formed on a semiconductor substrate, 2 , which preferably is a silicon substrate, to a thickness of about 80 Angstroms, followed by deposition of a poly 1 layer, 8 , to a depth of about 800 Angstroms. Active regions, 10 , are defined using isolating regions, such as shallow trench isolation regions, 4 . This is followed by deposition of a nitride layer, which preferably is a silicon nitride layer to a depth of about 2500 Angstroms. A photoresist layer, 14 , is then formed as shown in FIGS. 3 b and 4 b. The photoresist pattern, 14 , is used in etching the silicon nitride layer to achieve the shape of region 12 of FIG. 4 b. A poly 1 etch is performed, and it is preferred to achieve the shape of region 8 as shown in FIG. 4 b according to the method described in U.S. Pat. No. 6,090,668 to Lin et al., which is herein incorporated by reference. Such sloped segments of the poly 1 layer provide improved operation of the memory cell. After removal of the photoresist, an oxide 2 layer, 16 , is deposited to a thickness of about 3000 Angstroms and a CMP (chemical-mechanical polishing) step is performed. A second photoresist layer, 18 , is formed and used in successively etching the silicon nitride layer and the poly 1 layer to achieve the structure shown in FIGS. 3 c and 4 c. Source regions 20 are formed by a P ion implantation at energy of about 20 keV and to a dose of about 4E14 per cm2. Removal of the second photoresist layer is followed by deposition of an oxide 3 layer to a depth of about 500 Angstroms, which enhances the lateral diffusion of the source implant. An oxide 3 etching step is performed to achieve oxide 3 spacers, 22 . A polysilicon deposition is performed to a depth of about 3000 Angstroms and a CPM step on this layer produces a poly 2 region 24 , which serves to contact the source 20 . At this stage the structure is as depicted in FIGS. 3 d and 4 d . The method proceeds with oxidation of poly 2 , region 24 , to form about 200 Angstroms of oxide 4 , region 26 . Next the nitride layer 12 is removed, and successive etches are performed of the poly 1 layer, 8 , and floating gate oxide 1 layer, 6 . After a poly 3 deposition, 30 , to about 2000 Angstroms, the structure is as shown in FIGS. 3 e and 4 e. At this point the method of the invention deviates from traditional methods. Instead of immediately performing an etch back step to form poly 3 spacers 30 , as in traditional methods, in which a rounded shape results, in the method of the invention a CMP process step is inserted before the poly 3 etch back. After the poly CMP step a more square profile is achieved for the poly 3 , 42 . As a result an essentially vertical profile is achieved for the poly 3 spacers 44 , which are formed by etching back the poly 3 region, 42 . The oxide 5 layer remaining on the drain area is now removed, which can be accomplished by a wet dip oxide etch or by an oxide dry etch. There follows an oxidation step in which oxide 6 , 46 , is grown to a thickness of about 600 Angstroms over the exposed poly 3 . An oxide of about half this thickness, 48 , is grown, in this oxidation step, to the undoped silicon region in the drain area, so that the thickness of the oxide in that region is about 300 Angstroms. Such a difference in thickness is due to the significantly reduced oxide growth rate of undoped silicon substrate as compared to doped poly. The oxide growth rate of doped poly is about twice that of undoped silicon. The difference in thickness of the oxides in regions 46 and 48 , a consequence of the difference in oxide growth rate, is important to the implementation of the invention. The next step is to form drain regions 52 . This is preferably accomplished with an implant of As ions at energy of about 60 keV and to a dose of about 4E15 per cm2. An oxide spacer etch follows in which all the oxide 48 over the drain region is etched away, but oxide 6 layers over poly 3 , 50 , will remain, however at a reduced thickness of about 260 Angstroms. The remaining oxide 6 layer serves as an insulating layer for the underlying poly 3 spacers, which act as word lines. A square profile is preferred since more oxide remains, subsequent to the spacer oxide etch, on the word line sidewalls for a square profile. This allows for the direct deposition of a poly 4 layer, which is performed to a depth of about 2000 Angstroms. No intervening interlevel dielectric layer is required. Another photoresist layer is formed and patterned so that after etching poly 4 , bit lines 54 are formed connecting to the drain regions, 52 through the poly 4 contact regions 56 . This completes the formation of a split gate flash cell according to the invention, which is shown in FIGS. 3 j and 4 j. [0016] Bit lines, 54 and bit contacts, 56 are insulated from the word lines, 30 by an oxide 6 layer, 46 that was grown directly on the word lines and is of a thickness sufficient to reliably insulate the word lines from the bit lines and bit contacts. No area need be devoted to account for misalignment or imperfect accuracy in the dimension of these regions. Self-alignment of the bit line and bit contact to the word line, as in the structure of the present invention, eliminates the reliability issue, allows a reduction in cell area and facilitates shrinking the cell size. [0017] Other preferred embodiments of the invention are applicable to situations where, in partially fabricated devices on a silicon substrate there are openings to a gate oxide layer disposed over the substrate. The openings are to contain a first conductive line disposed over the oxide and a contact region, connecting a second conductive line to the silicon substrate that needs to be insulated from the first conductive line. The second conductive line passes over the first conductive line and needs to be insulated from the first conductive line. In the method of the invention a first polysilicon layer is deposited to more than cover the openings. A CMP step is performed stopping at the top of the openings. Etching back the first polysilicon layer follows to produce polysilicon spacers with essentially rectangular profiles over the gate oxide layer adjacent to the opening sidewalls and defining diminished openings to the gate oxide layer. An oxidation step is then performed that results in an oxide layer grown over the exposed surfaces of the polysilicon spacers. For a gate oxide layer about 170 Angstroms thick the oxide over the polysilicon spacers should be grown to a thickness of about 600 Angstroms. Additional oxide is also grown during the oxidation step, but to a lesser extent, under the exposed gate oxide layer in the openings. The thickness of this layer is increased to about 340 Angstrom, if the original gate oxide thickness was 170 Angstroms and 600 Angstroms is grown on the polysilicon spacers. Only about 170 Angstroms is added mainly due to the significantly reduced oxide growth rate of the undoped silicon substrate as compared to doped polysilicon. The oxide growth rate of doped poly is about twice that of undoped silicon. Also contributing to the relatively small increase in thickness is that the additional oxide is grown under the gate oxide layer that was there prior to the oxidation step. Drain regions can now be formed if required. This is preferably accomplished with an implant of As ions at energy of about 60 keV and to a dose of about 4E15 per cm2. A spacer oxide etch follows in which all the oxide over the silicon substrate of the openings is etched away, but an oxide layer will remain over the polysilicon spacer, however at a reduced thickness of about 260 Angstroms. This remaining oxide layer serves as an insulating layer for the underlying polysilicon spacers. A deposition of a second polysilicon layer follows, which is preferably performed to a depth of about 2000 Angstroms. No intervening interlevel dielectric layer is required. The second polysilicon layer filling the openings serve as contact regions. A photoresist layer is formed and patterned so that after etching the second polysilicon conductive lines are formed connected to the silicon substrate through the contact regions. [0018] While the invention has been particularly shown and described with reference to the preferred embodiments thereof, it will be understood by those skilled in the art that various changes in form and detail may be made without departing from the spirit and scope of the invention.

A new structure is disclosed for semiconductor devices in which contact regions are self-aligned to conductive lines. Openings to a gate oxide layer, in partially fabricated devices on a silicon substrate, have insulating sidewalls. First polysilicon lines disposed against the insulating sidewalls extend from below the top of the openings to the gate oxide layer. Oxide layers are grown over the top and exposed sides of the first polysilicon lines serving to insulate the first polysilicon lines. Polysilicon contact regions are disposed directly over and connect to silicon substrate regions through openings in the gate oxide layer and fill the available volume of the openings. Second polysilicon lines connect to the contact regions and are disposed over the oxide layers grown on the first polysilicon lines.

BACKGROUND [0001] Technical Field [0002] The present disclosure relates to integrated circuit devices and, in particular, to transistors in a static random access memory array. [0003] Description of the Related Art [0004] The cost of manufacturing an integrated circuit (IC) is related to the number of process steps required to fabricate the IC. Reducing the number of process steps required to fabricate an IC may reduce the cost of manufacturing the IC in a number of ways. For example, reducing the number of process steps may decrease the duration of the fabrication process, thereby freeing up expensive resources, such as fabrication facilities and equipment, for use in the fabrication of additional ICs. As another example, reducing the number of process steps may increase the yield of the fabrication process, thereby reducing the cost per IC. [0005] As semiconductor feature sizes have continued to shrink, conventional field-effect transistors (FETs) have increasingly suffered from problems such as short-channel effects, high leakage current, and high static power dissipation. Many alternatives to the conventional planar FET structure have been studied, including the non-planar finFET. A finFET is a field-effect transistor in which a portion of the transistor's semiconductor material forms a fin-like structure. Relative to conventional planar FETs, a finFET may exhibit reduced short-channel effects, leakage current, and/or static power dissipation. [0006] Methods of fabricating finFETs on integrated circuits are known. For example, a conventional finFET fabrication process may include the following steps: formation and filling of trenches between the finFET and other semiconductor devices for shallow-trench isolation; removal of portions of the semiconductor substrate to form a fin; formation of sidewall spacers for a dummy gate; formation of the dummy gate to shield the body of the finFET from the dopants; implantation of dopants into the finFET's source and drain regions; annealing of the integrated circuit to activate the dopants; removal of the dummy gate; and formation of the real finFET gate between the spacers, so that the gate aligns with the finFET's undoped body region. During implantation of dopants, the dummy gate may shield the body of the finFET from the dopants. BRIEF SUMMARY [0007] According to an embodiment, there is provided a semiconductor device fabrication method. The method includes forming a fully-depleted channel of a finFET in a cell of a static random-access memory (SRAM) by doping, in a same processing step, portions of a silicon-on-insulator (SOI) substrate of an integrated circuit. A first of the portions corresponds to a first doped region of a finFET. A second of the portions corresponds to a second doped region of the finFET. A third of the portions corresponds to a via contact. The method further includes, after the doping, forming a gate of the finFET. [0008] According to another embodiment, there is provided a semiconductor device fabrication method. The method includes doping, in a same processing step, first and second portions of a substrate of an integrated circuit. The first portion corresponds to a doped region of a semiconductor device. The second portion corresponds to a via contact. The method further includes, after the doping, forming the gate of the semiconductor device. [0009] According to another embodiment, there is provided an integrated circuit including a semiconductor device fabricated by the method described in the preceding paragraph. BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS [0010] For an understanding of some embodiments, reference will now be made by way of example only to the accompanying Figures in which: [0011] FIG. 1 shows a block diagram of a field effect transistor (FET) 100 , according to some embodiments; [0012] FIG. 2 shows a perspective view of a planar FET 100 a, according to some embodiments; [0013] FIGS. 3A, 3B, and 3C show views of a finFET 100 b (in particular, a perspective view, a cross-sectional view along line B-B, and a cross-sectional view along line A-A, respectively), according to some embodiments; [0014] FIG. 3D shows a cross-sectional view of a finFET 100 b, according to another embodiment; [0015] FIG. 3E shows a cross-sectional view of a finFET 100 b, according to another embodiment; [0016] FIG. 3F shows a cross-sectional view of a finFET 100 b, according to another embodiment; [0017] FIGS. 4A and 4B show views of an independent-gate finFET 100 c (in particular, a perspective view and a cross-sectional view along line A-A, respectively), according to some embodiments; [0018] FIG. 4C shows a perspective view of a segmented-fin finFET 100 d, according to some embodiments; [0019] FIG. 5A shows a flowchart of a method of fabricating a semiconductor device, according to some embodiments; [0020] FIG. 5B shows a flowchart of a method of doping portions of the semiconductor substrate, according to some embodiments; [0021] FIG. 5C shows a flowchart of a method of isolating doped regions of semiconductor devices from each other, according to some embodiments; [0022] FIG. 5D shows a flowchart of a method of forming a gate of a semiconductor device, according to some embodiments; [0023] FIG. 6 shows a schematic of an SRAM cell, according to some embodiments; [0024] FIG. 7 shows an integrated circuit layout of the SRAM cell of FIG. 6 , according to some embodiments; [0025] FIGS. 8A-8C show integrated circuit 700 after mask-provision sub-step 512 has been performed (in particular, FIGS. 8A, 8B, and 8C show a top view of integrated circuit 700 , a cross-sectional view of integrated circuit 700 along line A-A, and a cross-sectional view of integrated circuit 700 along line B-B, respectively), according to some embodiments; [0026] FIGS. 9A-9C show integrated circuit 700 after mask-opening sub-step 514 and implantation/activation sub-step 516 have been performed (in particular, FIGS. 9A, 9B, and 9C show a top view of integrated circuit 700 , a cross-sectional view of integrated circuit 700 along line A-A, and a cross-sectional view of integrated circuit 700 along line B-B, respectively), according to some embodiments; [0027] FIGS. 10A-10C show integrated circuit 700 after mask-opening sub-step 522 and inverse-mask sub-step 524 have been performed (in particular, FIGS. 10A, 10B, and 10C show a top view of integrated circuit 700 , a cross-sectional view of integrated circuit 700 along line A-A, and a cross-sectional view of integrated circuit 700 along line B-B, respectively), according to some embodiments; [0028] FIGS. 11A-11C show integrated circuit 700 after mask-removal sub-step 526 and substrate-removal sub-step 528 have been performed (in particular, FIGS. 11A, 11B, and 11C show a top view of integrated circuit 700 , a cross-sectional view of integrated circuit 700 along line A-A, and a cross-sectional view of integrated circuit 700 along line B-B, respectively), according to some embodiments; [0029] FIGS. 11D-11E show integrated circuit 700 after dielectric layer 812 and gate materials 814 and 816 have been provided (in particular, FIGS. 11D and 11E show a cross-sectional view of integrated circuit 700 along line A-A and a cross-sectional view of integrated circuit 700 along line B-B, respectively), according to some embodiments; [0030] FIGS. 12A-12C show integrated circuit 700 after mask-alignment sub-step 534 and material-removal sub-step 536 have been performed (in particular, FIGS. 12A, 12B, and 12C show a top view of integrated circuit 700 , a cross-sectional view of integrated circuit 700 along line A-A, and a cross-sectional view of integrated circuit 700 along line B-B, respectively), according to some embodiments; and [0031] FIGS. 13A-13C show integrated circuit 700 after formation of interconnect layers and through vias (in particular, FIGS. 13A, 13B, and 13C show a top view of integrated circuit 700 , a cross-sectional view of integrated circuit 700 along line A-A, and a cross-sectional view of integrated circuit 700 along line B-B, respectively), according to some embodiments. [0032] For clarity, the same elements have been designated with the same reference numerals in the different drawings and, further, as usual in the representation of integrated circuits, the various drawings are not to scale. For clarity, only those steps and elements which are useful to the understanding of the described embodiments have been shown and will be discussed. DETAILED DESCRIPTION [0033] Conventional finFET fabrication methods may require a large number of fabrication processing steps and/or rely on fabrication techniques that are unlikely to scale to processing nodes with smaller feature sizes (e.g., features sizes of 65 nm or less). The inventors have recognized and appreciated that a simpler process for fabricating finFETs (e.g., a process with fewer processing steps and/or processing steps that scale to feature sizes of 65 nm or less) may increase fabrication yields and reduce fabrication expenses. [0034] According to an embodiment, a semiconductor fabrication method may include a doping step in which dopants are implanted in portions of an integrated circuit substrate corresponding to doped regions of a finFET and a via contact. The method may also include a gate-formation step, performed after the doping step, in which the gate of the semiconductor device is formed. [0035] In some embodiments, during the same process step in which the finFET gate is formed, a local interconnect coupling the gate of the finFET to a via contact may be formed from the same material as the finFET gate. [0036] In some embodiments, the device produced by the semiconductor fabrication method may be an SRAM, and the finFET may be an element of an SRAM cell. [0037] In some embodiments, the method may also include an isolation step, performed after the doping step, in which doped regions of different finFETs are isolated from each other. [0038] In some embodiments, the fin channel of the integrated circuit may be a fully-depleted silicon-on-insulator (FDSOI) substrate. [0039] The features described above, as well as additional features, are described further below. These features may be used individually, all together, or in any combination, as the technology is not limited in this respect. [0040] FIG. 1 shows a block diagram of a field effect transistor (FET) 100 , according to some embodiments. FET ( 100 ) includes a gate 102 , two doped regions (drain 104 and source 106 ), and a body region 108 . When FET 100 is suitably biased, a channel may form in body region 108 between drain 104 and source 106 . The conductivity of the channel may be controlled, at least in part, by a voltage (VGS) applied across the gate and source terminals. When a voltage (VDS) is applied across the drain and source terminals, current may flow through the channel. [0041] In some embodiments, portions of a semiconductor device such as FET 100 may be formed in and/or on a semiconductor substrate. In some embodiments, a substrate may include silicon, silicon germanium, silicon carbide, and/or other material(s) known to one of ordinary skill in the art or otherwise suitable for fabricating semiconductor devices. In some embodiments, a substrate may be a bulk substrate, a silicon-on-insulator (SOI) substrate, a strained-silicon-direct-on-insulator (SSDOI) substrate, a strained heterostructure-on-insulator (HOT) substrate, or any other type of substrate known to one of ordinary skill in the art or otherwise suitable for fabricating semiconductor devices. In some embodiments, portions of a substrate may be partially or fully depleted of charge carriers. In some embodiments, portions of a substrate may be strained. For example, portions of a substrate which are configured to operate as transistor channels may be tensilely or compressively strained to enhance the mobility of charge carriers in the channels. [0042] In some embodiments, the doped regions of a semiconductor device (e.g., drain 104 and source 106 of FET 100 ) may be regions of a semiconductor substrate that are doped (e.g., heavily doped) with charge carriers. The charge carriers may be introduced into the doped regions and activated through techniques known to one of ordinary skill in the art or otherwise suitable for modifying the electrical properties of a region of a semiconductor substrate, including but not limited to ion implantation and annealing. [0043] The gate of a semiconductor device (e.g., gate 102 of FET 100 ) may include, for example, polysilicon, one or more metallic materials, and/or any other materials known to one of ordinary skill in the art or otherwise suitable for forming a gate. In some embodiments, the gate and channel of a semiconductor device, such as FET 100 , may be separated from each other by a dielectric layer. In some embodiments, the dielectric layer may include a dielectric material such as polysilicon, a high-k dielectric material (e.g., a material having a dielectric constant higher than the dielectric constant of polysilicon), and/or any other material known to one of ordinary skill in the art or otherwise suitable for insulating a transistor gate and channel from each other. For example, a dielectric layer may include hafnium oxide (HfO 2 ). [0044] In some embodiments, the gate of a semiconductor device (e.g., gate 102 of FET 100 ) may include or be partially or fully covered by a spacer layer, a liner, a capping layer, and/or any other type of ‘gate-covering layer.’ A gate-covering layer may be formed near the gate of a semiconductor device (e.g., over the gate and/or adjacent to the sidewalls of the gate) by techniques known to one of ordinary skill in the art or otherwise suitable for forming a gate-covering layer, including but not limited to deposition and photolithographic patterning of a gate-covering material. In some embodiments, a gate-covering layer may include a nitride and/or an oxide, such as silicon nitride (SiN) or silicon oxide (SiO). In some embodiments, a gate-covering layer may insulate the gate from other portions of the integrated circuit, facilitate a self-aligning transistor fabrication process, apply stress to the transistor channel, etc. [0045] FIG. 2 shows a perspective view of a planar FET 100 a, according to some embodiments. In the example of FIG. 2 , FET 100 a includes a body region 108 , drain 104 , and source 106 formed in a semiconductor substrate 110 , a dielectric layer 112 formed over the channel portion 109 of body region 108 , and a gate 102 formed over dielectric layer 112 . In planar FET 100 a, the surface of body region 108 over which dielectric layer 112 and gate 102 are formed is planar. [0046] FIGS. 3A, 3B, and 3C show views of a finFET 100 b, according to some embodiments. FIG. 3A shows a perspective view of finFET 100 b. FIG. 3B shows a cross-sectional view of finFET 100 b along line B-B. FIG. 3C shows a cross-sectional view of finFET 100 b along line A-A. [0047] In some embodiments, a finFET may be a FET in which a fin structure includes at least a portion of the transistor body. In the example of FIGS. 3A-3C , finFET 100 b includes a fin 114 which protrudes upward from substrate 110 and in which body region 108 is formed. In some embodiments, a fin 114 may be a semiconductor structure which protrudes from, is suspended over, or is layered over a portion of substrate 110 . In some embodiments, fin 114 may be formed from substrate 110 (e.g., by removing portions of substrate 110 adjacent to fin 114 ). In some embodiments, fin 114 may be formed from a semiconductor layer of substrate 110 , and portions of substrate 110 below fin 114 may be formed from a buried oxide (BOX) layer of substrate 110 . In the example of FIGS. 3A-3C , fin 114 also includes at least portions of drain 104 and source 106 . [0048] In some embodiments, fin 114 may be a thin structure. For example, the thickness 116 of fin 114 may be less than its height 115 (e.g., the thickness may be between 5% and 80% of the height, between 5% and 75% of the height, between 5% and 60% of the height, between 5% and 50% of the height, between 5% and 40% of the height, between 5% and 25% of the height, or between 5% and 20% of the height). As just one example, the height 115 and thickness 116 of fin 114 may be 32 nm and 8 nm, respectively. [0049] Embodiments of fin 114 are not limited by the properties of the fin or by the method of fabricating the fin. In some embodiments, a fin's configuration (e.g., shape, orientation, material composition, etc.) may be a configuration known to one of ordinary skill in the art or otherwise suitable for a fin structure. Embodiments of fin 114 may be formed using any technique known to one of ordinary skill in the art or otherwise suitable for forming a fin structure. [0050] FinFET 100 b also includes a gate 102 and dielectric layer 112 which insulates the gate from body region 108 of fin 114 . In the embodiment of FIGS. 3A-3C , gate 102 wraps around fin 114 , such that portions of gate 102 are over body region 108 (e.g., adjacent to an upper surface of the body region), and portions of gate 102 are beside body region 108 (e.g., adjacent to sidewalls of the body region). In some embodiments, portions of gate 102 may be over, above, beside, below, and/or under body region 108 . In the embodiment of FIGS. 3A-3C , gate 102 is structured as a single electrical node. FinFETs in which a gate is structured as a single electrical node may be referred to as ‘dependent-gate’ finFETs. In some embodiments, gate 102 may be structured as two or more independent electrical nodes. FinFETs in which the gate 102 is structured as two or more independent electrical nodes may be referred to as ‘independent-gate’ finFETs. [0051] FIGS. 3D-3F show cross-sectional views of finFET 100 b, according to some other embodiments. In the embodiments of FIGS. 3D-3F , portions of gate 102 are below body region 108 of fin 114 . In the embodiment of FIG. 3D , which may be referred to as a pi-gate finFET, portions of gate 102 are below body region 108 of fin 114 but not under body region 108 of fin 114 . In the embodiment of FIG. 3E , which may be referred to as an omega-gate (a-gate) finFET, portions of gate 102 are both below and under body region 108 of fin 114 . In the embodiment of FIG. 3F , which may be referred to as a gate-all-around finFET, gate 102 forms a ring around body region 108 of fin 114 , such that all portions of body region 108 are beside, above, and below portions of gate 102 . [0052] FIGS. 4A and 4B show views of an independent-gate finFET 100 c, according to some embodiments. FIG. 4A shows a perspective view of independent-gate finFET 100 c . FIG. 4B shows a cross-sectional view of independent-gate finFET 100 c along line A-A. In an independent-gate finFET, the gate may be structured as two or more independent nodes. In the example of FIGS. 4A and 4B , the finFET gate is structured as two independent nodes, 102 a and 102 b. [0053] FIG. 4C shows a perspective view of a segmented-fin finFET 100 d, according to some embodiments. In a segmented-fin finFET, the transistor's body region may be segmented among two or more fins. In the example of FIG. 4C , the transistor's body region (not shown) is segmented among two fins 114 a and 114 b. [0054] Embodiments are not limited to the finFET structures illustrated in FIGS. 3-4 and described above. Embodiments may include (or be used to fabricate) any finFET structure known to one of ordinary skill in the art or otherwise suitable for operating as a finFET, including but not limited to segmented-fin finFETs with any number of fins, finFETs with any number of independent and/or dependent gates, finFETs with fins of any shapes or dimensions, finFETs with gates of any shape, etc. [0055] FIG. 5A shows a flowchart of a method of fabricating a semiconductor device, according to some embodiments. In step 502 of the method of FIG. 5A , portions of the semiconductor substrate are doped. The doped portions correspond to a doped region of a semiconductor device and a via contact. In some embodiments the semiconductor device may be, for example, a finFET, and the doped region may be a source or drain of the finFET. In some embodiments, a via contact may be an opening in an insulating layer through which a doped region of a semiconductor substrate is conductively coupled to an interconnect layer of an integrated circuit. In some embodiments, the portions of a substrate corresponding to doped regions of semiconductor devices and to via contacts may be doped in a same process step of a semiconductor fabrication process. Forming drain/source doped regions and via contact doped regions in a same processing step may facilitate alignment of semiconductor device terminals (e.g., drains and sources) with via contacts, thereby allowing the fabrication process to more easily scale to process nodes with smaller feature sizes. [0056] In some embodiments, the method of FIG. 5A may be a gate-last process (i.e., a process in which the gate of a semiconductor device is fabricated after the doped regions of the semiconductor device have been doped). In some gate-last embodiments of the method of FIG. 5A , dummy gates and/or sidewall spacers may not be used to align a semiconductor device's later-formed gate with the device's earlier-formed doped regions. In this manner, embodiments of FIG. 5A may reduce the number of process steps used to fabricate a semiconductor device, relative to conventional fabrication processes. [0057] FIG. 5B shows a flowchart of a method of doping portions of the semiconductor substrate, according to some embodiments. In some embodiments, step 502 of the method of FIG. 5A may be performed according to the method of FIG. 5B . In step 512 of FIG. 5B , a mask is provided over a semiconductor substrate of an integrated circuit. The mask may be provided using any technique known to one of ordinary skill in the art or otherwise suitable for masking an integrated circuit, including but not limited to depositing the mask or growing the mask. In some embodiments the mask may be a hard mask, such as a silicon nitride (SiN) mask or a silicon oxide (SiO) mask. [0058] In step 514 of FIG. 5B , the mask is opened. In some embodiments, opening the mask includes removing portions of the mask over a portion of the substrate that corresponds to a doped region of the semiconductor device and over a portion of the substrate that corresponds to a via contact. The mask may be opened using any technique known to one of ordinary skill in the art or otherwise suitable for opening a mask, including but not limited to patterning the mask and etching the mask. For example, in some embodiments, photolithographic patterning and plasma etching or reactive ion etching (ME) may be used to open the mask. [0059] In step 516 of FIG. 5B , dopants are implanted into the semiconductor substrate through the open portions of the mask, and the implanted dopants are activated. Dopants may be implanted in the substrate using techniques known to one of ordinary skill in the art or any other suitable techniques for modifying the electrical properties of a region of a semiconductor substrate, including but not limited to ion implantation. In some embodiments, different dopants may be implanted in the doped regions of p-channel FETs and n-channel FETs. The implanted dopants may be activated using techniques known to one of ordinary skill in the art or any other suitable techniques, including but not limited to annealing the integrated circuit. [0060] In some embodiments, the implantation of dopants may be controlled to achieve full or partial depletion of charge carriers from a portion of the substrate corresponding to the channel region of a semiconductor device. In embodiments where full or partial depletion of charge carriers is performed, the integrated circuit's semiconductor substrate may be a fully-depleted silicon-on-insulator (FDSOI) substrate (e.g., an SOI substrate in which the thickness of the semiconductor layer over the buried oxide layer is between 1 nm and 45 nm, between 2 nm and 35 nm, or between 2 nm and 10 nm). Performing full or partial depletion of charge carriers from a semiconductor device's channel region may reduce the impact of short-channel effects and/or barrier-induced leakage on the operations of the semiconductor device. [0061] The method illustrated in FIG. 5B is just one example of a method of doping portions of a substrate. In some embodiments, techniques known to one of ordinary skill in the art or otherwise suitable for doping portions of a semiconductor substrate may be used. [0062] In step 504 of the method of FIG. 5A , the portion of the substrate that corresponds to the doped region of the semiconductor device is isolated from a portion of the substrate that corresponds to a doped region of a second semiconductor device. In some embodiments, the second semiconductor device may be finFET, and the doped region of the second semiconductor device may be a source or drain. In some embodiments, two doped regions may be partially or fully isolated from each other when portions of the substrate located between the doped regions are removed, and/or when an insulating material is interposed between the doped regions. In some embodiments, the techniques used to isolate the doped regions of semiconductor devices from each other may also result in the formation of fin structures for the semiconductor devices. [0063] FIG. 5C shows a flowchart of a method of isolating doped regions of semiconductor devices from each other, according to some embodiments. In some embodiments, the method of FIG. 5C may be applied to an integrated circuit which includes a first mask with openings over portions of the substrate corresponding to the doped regions of the semiconductor devices. In some embodiments, the mask may also have openings over portions of the substrate which correspond to one or more via contacts. In step 522 of the method of FIG. 5C , additional portions of the first mask are opened. The additional openings may be over portions of the substrate corresponding to the bodies of the semiconductor devices. As in step 514 of FIG. 5B , the mask may be opened using any technique known to one of ordinary skill in the art or otherwise suitable for opening a mask. [0064] In step 524 of FIG. 5C , an inverse mask is formed in the openings of the first mask. In some embodiments, the inverse mask may be formed over portions of the substrate corresponding to doped regions and body regions of semiconductor devices (e.g., the fin structures of finFETs) and/or to via contacts. In some embodiments, the inverse mask may be formed by providing a second mask over the first mask. In some embodiments, the second mask may be formed from a different material in the first mask. For example, in embodiments where the first mask is a nitride material, the second mask may be in oxide material, such as silicon oxide (SiO). In embodiments where the first mask is in oxide material, the second mask may be a nitride material, such as silicon nitride (SiN). As in step 512 of FIG. 5B , the second mask may be provided using any technique known to one of ordinary skill in the art or otherwise suitable for masking an integrated circuit. When the second mask is provided, portions of the second mask may partially or fully fill the openings in the first mask. [0065] In some embodiments, the inverse mask may be formed from the second mask by removing portions of the second mask that are not located in openings of the first mask. The portions of the second mask that are not located in openings of the first mask may be removed using techniques known to one of ordinary skill in the art or any other techniques suitable for removing portions of a mask, including but not limited to chemical-mechanical polishing (CMP). For example, a chemical-mechanical polishing step may be performed to remove portions of the second mask that are over the first mask, leaving the first mask intact with the openings in the first mask filled by portions of the second mask. [0066] In step 526 of FIG. 5C , the first mask may be removed from the integrated circuit, leaving an inverse mask over the portions of the substrate that were accessible through the openings in the first mask. The first mask may be removed using techniques known to one of ordinary skill in the art or any other suitable techniques for removing the material of the first mask without removing the material the second mask. For example, in some embodiments, plasma etching or reactive ion etching may be used to remove the first mask without removing the second mask (and portions of the substrate below the second mask). [0067] In step 528 of FIG. 5C , at least some portions of the substrate which are not covered by the inverse mask are removed. Portions of the substrate may be removed using techniques known to one of ordinary skill in the art or otherwise suitable for removing portions of a semiconductor substrate, including but not limited to plasma etching or reactive ion etching. In some embodiments, removal of portions of the substrate not covered by the inverse mask may result in the formation of fins corresponding to drains, sources, and/or body regions of finFETs. [0068] In some embodiments, the portions of the substrate removed during step 528 may include a particular portion of the substrate located between the doped regions of two semiconductor devices. In some embodiments, the substrate may be a silicon-on-insulator (SOI) substrate, and the particular portion of the substrate removed during step 528 may border on the portions of the substrate corresponding to the doped regions of the semiconductor devices, and on a buried oxide (BOX) layer of the substrate. In some embodiments, the substrate may be a bulk substrate, and the particular portion of the substrate removed during step 528 may border on the portions of the substrate corresponding to the doped regions of the semiconductor devices, and on an underlying layer of the substrate. [0069] In some embodiments, after removal of portions of the substrate during step 528 , the portions of the substrate corresponding to the doped regions of the semiconductor devices may be partially or fully isolated from each other (e.g., not coupled to each other) in the layer in which they are formed. In some embodiments, the particular portion of the substrate removed during step 528 may constitute a minimum percentage of the undoped, non-body portions of the substrate within a specified region of the substrate, such as a rectangular box-shaped region, that includes the doped regions of the semiconductor devices. The specified percentage may be, for example, any percentage between 5% and 100%. [0070] The method illustrated in FIG. 5C is just one example of a method of isolating doped regions of semiconductor devices from each other. In some embodiments, techniques known to one of ordinary skill in the art or otherwise suitable for isolating regions of the semiconductor substrate from each other may be used, including but not limited to shallow trench isolation or deep trench isolation. However, the isolation method of FIG. 5C may scale more easily to process nodes with small feature sizes (e.g., 32 nm or less). [0071] In step 506 of the method of FIG. 5A , the gate of the semiconductor device is formed. In some embodiments, prior to forming the gate, an inverse mask may be removed and a dielectric layer may be deposited on the substrate, thereby insulating the remaining portions of the substrate from the materials to be deposited during formation of the gate. The dielectric layer may include, for example, a material with a high dielectric constant, such as hafnium oxide (HfO 2 ). [0072] In some embodiments, the gate of the semiconductor device and a local interconnect may be formed during a same process step of an integrated circuit fabrication process. In some embodiments, forming a local interconnect from a gate material and during a gate-formation step may reduce the number of process steps required to fabricate the integrated circuit. In some embodiments, the local interconnect may be shorter and/or have lower capacitance than an interconnect with the same endpoints that is routed through through-vias and an upper interconnect layer. [0073] FIG. 5D shows a flowchart of a method of forming a gate of a semiconductor device, according to some embodiments. In step 532 of FIG. 5D , one or more gate materials are provided over the substrate (e.g., on a dielectric layer). In some embodiments, the provided gate material(s) may include a work-function material (e.g., a metal carbide such as titanium carbide or a metal nitride such as titanium nitride) and a metallic material (e.g., aluminum, tungsten, and/or copper). In some embodiments, the gate material(s) may be provided by depositing the work-function material on the dielectric layer, removing portions of the work-function layer that were deposited over portions of the substrate corresponding to n-channel FETs, and depositing the metallic material over the work-function material and the exposed portions of the dielectric layer. However, embodiments are not limited in this regard. In some embodiments, any material(s) known to one of ordinary skill in the art or otherwise suitable for functioning as a gate of a semiconductor device (e.g., polysilicon and/or metallic materials) may be provided using techniques known to one of ordinary skill in the art or otherwise suitable for providing such material(s). [0074] In step 534 of FIG. 5D , a mask is aligned over the gate material(s). In some embodiments, protrusions from the surface of the integrated circuit may be used to facilitate alignment of the mask. Such protrusions may correspond, for example, to portions of the substrate that were isolated from each other during step 504 of the method of FIG. 5A (e.g., via contacts, doped regions of semiconductor devices, and/or body regions of semiconductor devices). In some embodiments, the alignment step may include an optical alignment technique in which the scattering of light by the protrusions is used to detect the locations of the protrusions. In some embodiments, the mask may contain openings over portions of the substrate corresponding to semiconductor devices gates and/or portions of the substrate corresponding to electrical interconnects, including but not limited to interconnects that are coupled to the gates of the semiconductor devices. In embodiments where a via contact and a doped region of a semiconductor device are defined in a same processing step, the use of the protrusion corresponding to the via contact as a mask-alignment reference may facilitate alignment of the mask with respect to the elements of the semiconductor device, such as a drain, source, gate, and/or fin. [0075] In step 536 of FIG. 5D , portions of the gate material(s) which do not correspond to a gate of the semiconductor device and/or to an electrical interconnect are removed. In some embodiments, the process of removing the gate material(s) may include patterning the top layer of gate material(s) through openings in the mask, removing the mask, and etching the gate material(s). In some embodiments, the etching may be plasma etching, reactive ion etching, or low temperature Cl 2 /H 2 or florin metal etch. Embodiments are not limited in this regard. In some embodiments, any technique known to one of ordinary skill in the art or otherwise suitable for selectively removing the gate material(s) may be used. [0076] The method illustrated in FIG. 5D is just one example of a method of forming a gate of a semiconductor device. In some embodiments, techniques known to one of ordinary skill in the art or otherwise suitable for gate formation may be used. [0077] In step 508 of FIG. 5A , other layers of the integrated circuit are formed. For example, in some embodiments, a contact oxide film may be deposited and polished to a desired thickness (e.g., by chemical-mechanical polishing), portions of the integrated circuit corresponding to through-vias and/or interconnect layers may be opened (e.g., using a Damascene process), via contacts may be silicided, through-via openings and/or interconnect layer openings may be filled with suitable liner materials (e.g., tantalum nitride or titanium nitride) and/or metallic materials (e.g., tungsten, aluminum, or copper), and chemical-mechanical polishing may be performed. In some embodiments interconnect layers (e.g., metal interconnect layers) may be formed above the semiconductor devices and coupled to the semiconductor devices by the through-vias. Embodiments are not limited in this regard. In some embodiments, the remaining portions of the integrated circuit may be fabricated using techniques known to one of ordinary skill in the art or any other suitable techniques for fabricating an integrated circuit. [0078] In some embodiments, steps of the method of FIG. 5A may be performed in the order illustrated in FIG. 5A or in some other order. For example, in some embodiments, isolation step 504 and/or gate-formation step 506 may be performed before doping step 502 . Some embodiments may include only a subset of the method steps illustrated in FIG. 5A . For example, some embodiments may include only steps 502 , 504 , and 506 . [0079] Embodiments of the method of FIG. 5A may be used, for example, to fabricate a memory device or a portion of a memory device, such as a memory cell. In some embodiments the method of FIG. 5A may be used to fabricate an SRAM (static random access memory) cell, such as SRAM cell 600 of FIG. 6 . FIG. 6 shows a schematic of an SRAM cell, according to some embodiments. The SRAM cell of FIG. 6 includes six finFETs 602 , 604 , 606 , 608 , 610 , and 612 . In some embodiments, finFETs 602 , 604 , 606 , and 610 may be n-channel finFETs, and finFETs 608 and 612 may be p-channel finFETs. FinFETs 602 and 604 are independent-gate (IG) finFETs, each having one gate coupled to a write line (W) and one gate coupled to a read/write line (RW). FinFETs 606 , 608 , 610 , and 612 are dependent-gate finFETs or tied-gate finFETs (e.g., independent-gate finFETs in which the independent gates are coupled to each other). [0080] In some embodiments, each of the SRAM cell's finFETs may have a single fin with a height of 32 nm, a width of 8 nm, and a channel length of 32 nm. However, embodiments are not limited in this regard. In some embodiments, each finFET's configuration (e.g., number of fins, type of gate, fin dimensions, etc.) may be a configuration known to one of ordinary skill in the art or otherwise suitable for a finFET of an SRAM cell. [0081] The operation of an embodiment of the SRAM cell illustrated in FIG. 6 is described by Liu et al. in “An Independent-Gate FinFET SRAM Cell for High Data Stability and Enhanced Integration Density,” in Proceedings of the 20th International IEEE SoC (System on Chip) Conference, 2007 . FinFETs 608 and 606 form an inverter which is cross coupled with a second inverter formed by finFETs 610 and 612 . The cross-coupled inverters store a binary value at node 621 and the inverse of that binary value at node 622 . FinFETs 602 - 604 control access to the SRAM cell. Setting write line (W) and read/write line (RW) low disconnects the cross-coupled inverters from bit lines BL and BLB. The SRAM cell is read by setting read/write line (RW) high while holding write line (W) low, which causes bit line BL to read out the binary value stored at node 621 (i.e., the output of the inverter formed by finFETs 606 and 608 ). The SRAM cell is written by setting read/write line (RW) and write line (W) high, which causes the value of the bit provided on bit line BL to be stored at node 621 . In some embodiments, access lines of the SRAM may include bit lines BL and BLB. In some embodiments, control lines of the SRAM may include write line W and read/write line RW. [0082] FIG. 7 shows the SRAM cell of FIG. 6 laid out on an integrated circuit 700 , according to some embodiments. As can be seen, gates 660 and 682 of finFET 608 and finFET 606 , respectively, are connected by a local interconnect 691 . Likewise, gates 661 and 684 of finFET 610 and finFET 612 , respectively, are connected by local interconnect 690 . FinFETs 608 and 612 share a drain 662 which is coupled to a supply voltage VDD through a via contact and an interconnect layer. Likewise, finFETs 606 and 610 share a source 663 which is coupled to ground through a via contact and an interconnect layer. The source 664 of finFET 608 and the drain 658 of finFET 606 are connected through via contacts and an interconnect layer 667 , which is also connected to local interconnect 690 through via contact 678 . The source 665 of finFET 612 and the drain 666 of finFET 610 are connected through via contacts and interconnect layer 668 , which is also connected to local interconnect 691 through via contact 680 . The source 650 of finFET 602 is coupled to bit line BL through a via contact and an interconnect layer. The source 670 of finFET 604 is coupled to bit line BLB through a via contact an interconnect layer. Each of finFETs 602 and 604 has a gate ( 656 and 677 , respectively) connected to read/write line (RW) through a local interconnect 671 , a via contact 672 , and an interconnect layer. FinFET 602 has a second gate 654 connected to write line (W) through a local interconnect 673 , a via contact 674 , and an interconnect layer. Likewise, finFET 604 has a second gate 678 connected to a write line (W) through a local interconnect 675 , a via contact 676 , and an interconnect layer. [0083] In some embodiments, the finFET gates and local interconnects may be formed from polysilicon and/or one or more metallic materials. In some embodiments, the local interconnects may be formed in the same processing step and with the same materials (or a subset of the same materials) as the gates of the finFETs. In some embodiments, at least some of the materials used to form the gates of the finFETs may be metallic materials. In some embodiments, the interconnect layers coupled to various nodes of the SRAM cell may be metal interconnect layers. [0084] Embodiments of the method of FIG. 5A may be used to fabricate the SRAM cell of FIG. 6 (e.g., using the layout of FIG. 7 ). FIGS. 8A-13C show embodiments of integrated circuit 700 at different times during fabrication according to an embodiment of the method of FIG. 5A . In FIGS. 8A-13C , reference numbers between 600 and 799 are used to identify structural elements of the SRAM cell (e.g., finFET doped regions, finFET fins, finFET gates, via contacts, etc.), while reference numbers between 800 and 899 are used to identify materials that form the structures and materials used during the fabrication of the structures (e.g., masks, silicon layers, dielectric layers, etc.). [0085] As described above, in the method of FIG. 5A , portions of a semiconductor substrate may be doped (step 502 ). In a sub-step of the doping step (e.g., step 512 of FIG. 5B ), a mask may be provided over a semiconductor substrate. FIGS. 8A-8C show integrated circuit 700 after mask-provision sub-step 512 has been performed, according to some embodiments. In particular, FIGS. 8A, 8B, and 8C show a top view of integrated circuit 700 , a cross-sectional view of integrated circuit 700 along line A-A, and a cross-sectional view of integrated circuit 700 along line B-B, respectively, according to some embodiments. [0086] In the example of FIGS. 8A-8C , integrated circuit 700 includes substrate 701 and a mask 802 . Substrate 701 may be any semiconductor substrate known to one of ordinary skill in the art or otherwise suitable for fabricating an SRAM cell, including but not limited to a fully-depleted silicon-on-insulator (FDSOI) substrate with a silicon layer 804 , a buried oxide (BOX) layer 806 , and a second silicon layer 808 . In some embodiments, silicon layer 804 may have a thickness of 32 nm or less. In some embodiments, BOX layer 806 may have a thickness between 10 nm and 50 nm. Mask 802 may include any material known to one of ordinary skill in the art or otherwise suitable for masking a substrate 701 , including but not limited to silicon nitride (SiN) or silicon oxide (SiO). [0087] In additional sub-steps of the doping step (e.g., steps 514 and 516 of FIG. 5B ), portions of the mask may be opened, portions of the substrate accessible through the openings in the mask may be implanted with dopants, and the implanted dopants may be activated. FIGS. 9A-9C show integrated circuit 700 after mask-opening sub-step 514 and implantation-activation sub-step 516 have been performed, according to some embodiments. In particular, FIGS. 9A , 9 B, and 9 C show a top view of integrated circuit 700 , a cross-sectional view of integrated circuit 700 along line A-A, and a cross-sectional view of integrated circuit 700 along line B-B, respectively, according to some embodiments. [0088] In the example of FIGS. 9A-9C , mask 802 includes eight openings over portions of substrate 701 which correspond to the doped regions ( 650 , 658 , 662 , 663 , 664 , 665 , 666 , 670 ) of the six finFETs; five openings over portions of substrate 701 which correspond to via contacts ( 672 , 674 , 676 , 678 , and 680 ); and twelve openings which correspond to non-body regions ( 704 ) of the fins of the six finFETs. Mask 802 does not include openings over the portions of the substrate that correspond to the body regions of the six finFETs ( 705 ). As can be seen in FIG. 9C , the portions of substrate 701 accessible through the openings in mask 802 are doped to form doped regions 707 . In some embodiments, different dopants may be used for the doped regions of the p-channel finFETs (i.e., finFETs 608 and 612 ) and the n-channel finFETs (i.e., finFETs 602 , 604 , 606 , and 610 ). In some embodiments, the portions of the substrate corresponding to the bodies ( 705 ) of the finFETs may be partially or fully depleted of charge carriers. [0089] Forming the finFET doped regions and the via contacts in the same processing step(s) may facilitate alignment of the finFET terminals with the SRAM cell's access lines (e.g., write line W, read/write line RW, and/or bit lines BL and BLB). [0090] In the method of FIG. 5A , doped regions of semiconductor devices (e.g., finFETs) may be isolated from each other (step 504 ). In a sub-step of the isolation step (e.g., steps 522 and 524 of FIG. 5C ), portions of a mask may be opened over portions of the substrate corresponding to the body regions of the semiconductor devices (e.g., finFETs), and an inverse mask may be formed in the openings of the first mask. FIGS. 10A-10C show integrated circuit 700 after mask-opening sub-step 522 and inverse-mask sub-step 524 have been performed on integrated circuit 700 , according to some embodiments. In particular, FIGS. 10A, 10B, and 10C show a top view of integrated circuit 700 , a cross-sectional view of integrated circuit 700 along line A-A, and a cross-sectional view of integrated circuit 700 along line B-B, respectively, according to some embodiments. [0091] In the example of FIGS. 10A-10C , the mask 802 includes the openings described above with respect to FIGS. 9A-9C , and additional openings above the portions of the substrate corresponding to the bodies of the six finFETs ( 705 ). In the example of FIGS. 10A-10C , the openings in mask 802 are filled with a second mask material 810 which forms a mask that is an inverse of mask 802 (an “inverse mask”). In some embodiments, inverse mask 810 may be formed from a material that differs from the material of mask 802 . For example, in embodiments where mask 802 comprises silicon nitride (SiN), inverse mask 810 may comprise silicon oxide (SiO). As another example, in embodiments where mask 802 comprises silicon oxide (SiO), inverse 810 mask may comprise silicon nitride (SiN). [0092] In additional sub-steps of the doping step (e.g., steps 526 and 528 of FIG. 5B ), the first mask and portions of the substrate which are not covered by the inverse mask may be removed. FIGS. 11A-11C show integrated circuit 700 after mask-removal sub-step 526 and substrate-removal sub-step 528 have been performed, according to some embodiments. In particular, FIGS. 11A, 11B, and 11C show a top view of integrated circuit 700 , a cross-sectional view of integrated circuit 700 along line A-A, and a cross-sectional view of integrated circuit 700 along line B-B, respectively, according to some embodiments. [0093] In the example of FIGS. 11A-11C , integrated circuit 700 includes inverse mask 810 and the portions of substrate layer 804 covered by the inverse mask, which form the doped regions ( 650 , 658 , 662 , 663 , 664 , 665 , 666 , 670 ) and bodies ( 705 ) of the six finFETs, and the doped regions of the five via contacts ( 672 , 674 , 676 , 678 , and 680 ). All other portions of substrate layer 804 within the SRAM cell have been removed, thereby isolating the finFETs and exposing the surface of buried oxide (BOX) layer 806 . [0094] In the method of FIG. 5A , gates of semiconductor devices (e.g., finFETs) are formed (step 506 ). As part of the gate-formation step, a dielectric layer may be provided on the integrated circuit. As another part of the gate-formation step (e.g., step 532 of FIG. 5D ), one or more gate materials may be provided over the dielectric layer. FIGS. 11D and 11E show integrated circuit 700 after dielectric layer 812 and gate materials 814 and 816 have been provided on the integrated circuit, according to some embodiments. In particular, FIGS. 11D and 11E show a cross-sectional view of integrated circuit 700 along line A-A and a cross-sectional view of integrated circuit 700 along line B-B, respectively, according to some embodiments. [0095] In the example of FIGS. 11D-11E , integrated circuit 700 includes dielectric layer 812 , gate material 814 , and gate material 816 . In some embodiments, dielectric layer 812 may include a high-k material, such as hafnium oxide (HfO 2 ). In some embodiments, dielectric layer 812 may be provided over substrate 701 throughout the SRAM cell. In some embodiments, gate material 814 may be a work-function material, such as a metal carbide (e.g., TiC) or a metal nitride (e.g., TiN). In some embodiments, gate material 814 may be provided over dielectric layer 812 in portions of the SRAM cell that correspond to p-channel finFETs. In some embodiments, gate material 816 may be a metallic material, such as aluminum, tungsten, or copper. In some embodiments, gate material 816 may be provided on integrated circuit 700 throughout the SRAM cell. [0096] In additional sub-steps of the gate-formation step (e.g., steps 534 and 536 of FIG. 5D ), a mask is aligned over the one or more gate materials, and portions of the gate material(s) are removed. FIGS. 12A-12C show integrated circuit 700 after mask-alignment sub-step 534 and material-removal sub-step 536 have been performed, according to some embodiments. In particular, FIGS. 12A, 12B, and 12C show a top view of integrated circuit 700 , a cross-sectional view of integrated circuit 700 along line A-A, and a cross-sectional view of integrated circuit 700 along line B-B, respectively, according to some embodiments. [0097] In the example of FIGS. 12A-12C , the gate material(s) remain on integrated circuit 700 in the local interconnects ( 671 , 673 , 675 , 690 , and 691 ) and the finFET gates ( 654 / 656 , 660 , 661 , 677 / 678 , 682 , 684 ), but have been removed from other portions of the SRAM cell, including the doped regions ( 650 , 658 , 662 , 663 , 664 , 665 , 666 , 670 ) and bodies ( 705 ) of the six finFETs, and the doped regions of the five via contacts ( 672 , 674 , 676 , 678 , and 680 ). In particular, the gates ( 660 , 661 ) of the p-channel finFETs ( 608 , 612 ) include gate material 814 (e.g., a work-function material) and gate layer 816 (e.g., a metallic material), the gates ( 654 / 656 , 677 / 678 , 682 , 684 ) of the n-channel finFETs ( 602 , 604 , 606 , 610 ) include gate material 816 , and the local interconnects ( 671 , 673 , 675 , 690 , and 691 ) include gate material 816 . With regards to finFET 602 , the independent gates ( 654 and 656 ) may be formed by removing the gate material(s) from the middle of the gate area, thereby creating a gap between the gate 654 and gate 656 . The same technique may be used to form the independent gates of finFET 604 . On portions of the integrated circuit not covered by the gate materials, dielectric layer 812 is exposed. For the reasons described above, using the gate material(s) as local interconnects to couple the finFET gates to each other, to write line W, and/or to read/write line RW may be advantageous, compared to using via contacts and an upper interconnect layer for those purposes. [0098] In the method of FIG. 5A , other layers of the integrated circuit are formed (step 508 ), such as interconnect layers and through-vias. FIGS. 13A-13C show integrated circuit 700 after formation of interconnect layers and through-vias. In particular, FIGS. 13A, 13B, and 13C show a top view of integrated circuit 700 , a cross-sectional view of integrated circuit 700 along line A-A, and a cross-sectional view of integrated circuit 700 along line B-B, respectively, according to some embodiments. [0099] As can be seen in FIG. 13B , integrated circuit 700 includes a dielectric layer 826 which insulates the components of the SRAM cell from interconnect layer 824 . In the example of FIG. 13B , interconnect layer 824 includes two sub-layers, 824 a and 824 b. In some embodiments, layer 824 a of interconnect layer 824 may be a metallic material, such as aluminum, tungsten, copper, or any other metallic or non-metallic material known to one of ordinary skill in the art or otherwise suitable for carrying electrical signals on an integrated circuit. In some embodiments, layer 824 b of interconnect layer 824 may be a liner formed from material(s) known to one of ordinary skill in the art or otherwise suitable for lining layer 824 a , such as tantalum nitride or titanium nitride. [0100] As can be seen in FIG. 13C , dielectric layer 826 also insulates the components of the SRAM cell from through-via layer 820 . In the example of FIG. 13C , through-via layer 820 includes two sub-layers, 820 a and 820 b. In some embodiments, layer 820 a of through-via layer 820 may be a metallic material, such as aluminum, tungsten, copper, or any other metallic or non-metallic material known to one of ordinary skill in the art or otherwise suitable for carrying electrical signals on an integrated circuit. In some embodiments, layer 820 b of through-via layer 820 may be a liner formed from material(s) known to one of ordinary skill in the art or otherwise suitable for lining layer 820 a, such as tantalum nitride or titanium nitride. In some embodiments, electrical contacts 818 may connect through-via layers 820 to the doped regions ( 650 , 658 , 662 - 666 , 670 ) of the six finFETs and/or to the doped regions of the via contacts ( 672 , 674 , 676 , 678 , 680 ). The electrical contacts 818 may include silicides formed on the portions of the doped regions adjacent to the through-vias 820 . [0101] Although the foregoing disclosure refers to finFETs as examples of semiconductor devices that may be fabricated using the method of FIG. 5A , embodiments are not limited in this regard. The techniques described herein may be used to fabricate any semiconductor device known to one of ordinary skill in the art, including but not limited to planar, non-planar, three-dimensional, single-gate and/or multi-gate devices, such as diodes, double-gate transistors, finFETs, tri-gate transistors, multi-gate transistors, delta transistors, pi-gate finFETs, omega-gate (Ω-gate) finFETs, gate-all-around finFETs, flexFETs, etc. [0102] Although the foregoing disclosure describes the SRAM cell schematic and layout of FIGS. 6 and 7 as examples of an SRAM cell that may be fabricated using the method of FIG. 5A , embodiments are not limited in this regard. The techniques described herein may be used to fabricate other layouts of the SRAM cell illustrated in FIG. 6 , SRAM cells other than the SRAM cell illustrated in FIG. 6 , and memory cells other than SRAM cells. [0103] Although the foregoing disclosure describes an SRAM cell as an example of a device that can be fabricated using the method of FIG. 5A , embodiments are not limited in this regard. Embodiments of the method of FIG. 5A may be used to fabricate any memory circuit, processing circuit, or communication circuit known to one of ordinary skill in the art or otherwise suitable for storing, processing, or communicating data. [0104] Terms used herein to describe positioning relationships of structural elements, such as “over,” “under,” “above,” “below,” “beside,” and “adjacent to,” should not be construed as requiring the structural elements to be in contact with each other or directly related (e.g., “over” should not be construed to mean “directly over” or to require that no other structures intervene between structure A and structure B when structure A is described as being “over” structure B), even where some or all embodiments of the structural elements illustrated in the Figures show the structural elements being in contact with each other and/or positioned without any structures intervening between them. [0105] Embodiments described in the present disclosure may be included in (or used to fabricate components of) any electronic or optoelectronic device, including but not limited to a memory, a microprocessor, a mobile electronic device, a mobile phone, a smart phone, a tablet computer, a laptop computer, a desktop computer, a server, a game console, a television, a display, or a communications device. [0106] Terms used herein to describe a doped region of a semiconductor device, such as “source” or “drain,” should not be construed to indicate that the doped region is necessarily biased at a lower or higher potential than any other doped region of the semiconductor device. [0107] A portion of an integrated circuit, such as a portion of a semiconductor substrate, “corresponds to” a structure, such as a fin, doped region, or transistor body, if that portion of the integrated circuit forms or will form that structure. Additional forms of correspondence between a portion of an integrated circuit and a structure will be apparent to one of ordinary skill in the art. [0108] Also, the phraseology and terminology used herein is for the purpose of description and should not be regarded as limiting. The use of “including,” “comprising,” or “having,” “containing,” “involving,” and variations thereof herein, is meant to encompass the items listed thereafter and equivalents thereof as well as additional items. [0109] Having thus described at least one illustrative embodiment of the invention, various alterations, modifications, and improvements will readily occur to those skilled in the art. Such alterations, modifications, and improvements are intended to be within the spirit and scope of the invention. Accordingly, the foregoing description is by way of example only and is not intended as limiting. The invention is limited only as defined in the following claims and the equivalents thereto.

Single gate and dual gate FinFET devices suitable for use in an SRAM memory array have respective fins, source regions, and drain regions that are formed from portions of a single, contiguous layer on the semiconductor substrate, so that STI is unnecessary. Pairs of FinFETs can be configured as dependent-gate devices wherein adjacent channels are controlled by a common gate, or as independent-gate devices wherein one channel is controlled by two gates. Metal interconnects coupling a plurality of the FinFET devices are made of a same material as the gate electrodes. Such structural and material commonalities help to reduce costs of manufacturing high-density memory arrays.

[0001] This application claims priority from U.S. Provisional Patent Application No. 61/636,767, filed on Apr. 23, 2012, the entire disclosure of which is incorporated herein by reference. BACKGROUND OF THE INVENTION [0002] The present invention relates generally to catheters for ablation or the like and, more particularly, to a disposable catheter with low COGS, ultrasonic lesion feedback, antipop monitoring, and force detection, and to a dual transducer with forward and side looking ultrasonic lesion feedback and optional force detection. BRIEF SUMMARY OF THE INVENTION [0003] Embodiments of the invention provide a force sensing catheter and supporting system for therapeutic or diagnostic applications. A catheter includes an elongated flexible catheter body having a distal end and a proximal end, a therapeutic or diagnostic tip on the distal end of the catheter body, and a catheter control handle or manipulation mechanism coupled to the proximal end of the catheter body. The tip region includes a most distal rigid tip portion mounted upon a more proximal abutting semi-rigid tip portion, the semi-rigid portion having known stiffness versus deflection (providing some useful tissue conforming behavior of the semi-rigid tip portion); and (i) an acoustic mirror, window, or membrane, and (ii) an acoustic transducer. The transducer is arranged to emit and receive an acoustic beam or ping which has been at least partially reflected from the mirror, window or membrane. Forces applied to the tip by contacting tissue cause the most distal rigid tip portion to deflect as a rigid whole because it is mounted upon the more proximal semi-rigid deflectable tip portion which angularly and axially deflects slightly but detectably. One of the (i) mirror/window/membrane or (ii) transducer is mounted in the most distal rigid portion and the other is mounted proximally to some or all of the semi-rigid portion (such as, for instance, a rigid proximal portion of the tip region). The transducer is thereby capable of detecting axial and/or angular bending deflections via the changing amplitude and/or time delay of reflections of the acoustic beam or ping reflected from the most distal rigid tip portion mounted upon and bodily movable upon said semi-rigid but deflectable intervening more-proximal tip portion. The catheter system computes from models or retrieves from lookup tables the force(s) which correlate with the system-observed tip deflections via the known angular stiffness and axial stiffness of the semi-rigid portion. The system reports or otherwise utilizes the force for a procedural control, recording, or safety reason. [0004] The inventive catheter will provide all of antipop monitoring, lesion feedback, and preferably both bending and axial force component magnitudes and their net vector sum. In principle, any so-equipped catheter may provide any one or more of lesion progress feedback, antipop monitoring, and force detection. In addition, the catheter may include dual opposed transducers, one forward looking and one backward/side looking via reflective redirection of its beam, which share a common attenuative backer block between them. By placing these opposed-facing transducers on a flexible tip one may also optionally utilize the ultrasound/mirror arrangement to measure force upon tissue. Such a device gives two excellent views of possible tissue targets rather than a single compromise view such as that given by 45 degree devices. [0005] In accordance with an aspect of the present invention, an ablation catheter with acoustic monitoring comprises: an elongated catheter body extending longitudinally between a proximal end and a distal end along a longitudinal axis; a distal member disposed adjacent the distal end, the distal member including an ablation element to ablate a biological member at a target region outside the catheter body; one or more acoustic transducers disposed in the distal member and each configured to direct an acoustic signal toward a respective target ablation region and receive reflection echoes therefrom; and an acoustic redirection member disposed in the distal member to at least partially redirect the acoustic signal from at least one of the acoustic transducers toward a tissue target. The distal member includes a most-distal portion, a proximal portion, and a deflectable portion between the most-distal portion and the proximal portion to permit deflection between the most-distal portion and the proximal portion of the distal member, the deflectable portion being more deflectable than at least one of the most-distal portion or the proximal portion. For the distal member, (i) the one or more acoustic transducers are mounted to the most-distal portion and the acoustic redirection member is mounted to the proximal portion, or (ii) the one or more acoustic transducers are mounted to the proximal portion and the acoustic redirection member is mounted to the most-distal portion of the distal member. [0006] In some embodiments, the most-distal portion of the distal member has no axial deflection and no bending deflection occurring within its own confines. The proximal portion of the distal member has no axial deflection and no bending deflection occurring within its own confines. The deflectable portion of the distal member, within its own confines, permits at least one of axial deflection along the longitudinal axis or bending deflection between the most-distal portion and the proximal portion of the distal member. The axial deflection is less than about 1 mm under an axial force of less than about 100 grams. The bending deflection is less than about 10 degrees under a bending moment of about 200 gram-millimeters. The deflectable portion of the distal member includes one of a laser machined metallic tube with cuts, a metallic tube with cuts machined by wet etching, a metallic tube with cuts machined by EDM (electric discharge machining), a polymeric tube, a braided tube, a woven tube, a convoluted tubular member, a mesh tube, a honeycombed tube, a wave washer, or a tubular member having bellows. At least one of the acoustic transducers is configured to detect a deflection via at least one of an amplitude change or a phase or time-delay change of a reflection of an acoustic signal reflected back from the acoustic redirection member. [0007] In specific embodiments, an acoustic reflection member is mounted to the same portion of the distal member as the acoustic redirection member and being configured to partially reflect an acoustic signal from at least one acoustic transducer of the acoustic transducers back to the at least one acoustic transducer. The at least one acoustic transducer is configured to detect a deflection via at least one of an amplitude change or a phase or time-delay change of a reflection of the acoustic signal reflected back from the acoustic reflection member. The acoustic reflection member comprises one of a partially reflective membrane or a partially reflective prism. [0008] In some embodiments, a controller is operable to determine, based on the detected deflection and a related force-deflection relationship of the deflectable portion of the distal member, a force between the distal member and the biological member. The acoustic signal comprises an acoustic beam or an acoustic ping. The one or more transducers comprise a sideways-redirected acoustic transducer to produce an acoustic signal that is redirected in a beam emanation direction nonparallel to the longitudinal axis to monitor a sideways-formed lesion, and a forward-directed acoustic transducer to produce another acoustic signal that is directed in another direction generally parallel to the longitudinal axis to monitor a forward-facing lesion, respectively. [0009] Another aspect of the invention is directed to an acoustic monitoring method for an ablation procedure using an ablation catheter which includes an elongated catheter body extending longitudinally between a proximal end and a distal end along a longitudinal axis; a distal member disposed adjacent the distal end, the distal member including an ablation element to ablate a biological member at a target region outside the catheter body; one or more acoustic transducers disposed in the distal member and each configured to direct an acoustic signal toward a respective target ablation region and receive reflection echoes therefrom; and an acoustic redirection member disposed in the distal member to at least partially redirect the acoustic signal from at least one of the acoustic transducers toward a tissue target. The distal member includes a most-distal portion, a proximal portion, and a deflectable portion between the most-distal portion and the proximal portion to permit deflection between the most-distal portion and the proximal portion of the distal member, the deflectable portion being more deflectable than at least one of the most-distal portion or the proximal portion. For the distal member, (i) the one or more acoustic transducers are mounted to the most-distal portion and the acoustic redirection member is mounted to the proximal portion, or (ii) the one or more acoustic transducers are mounted to the proximal portion and the acoustic redirection member is mounted to the most-distal portion of the distal member. The method comprises: ablating the biological member at the target region with the ablation element; directing one or more acoustic signals to the biological member and receiving reflection echoes from the biological member by the one or more acoustic transducers, the one or more acoustic signals including an acoustic signal directed toward the tissue target by the acoustic redirection member; and detecting a deflection between the most-distal portion and the proximal portion of the distal member based on reflection of an acoustic signal reflected back to at least one of the acoustic transducers. [0010] In some embodiments, the detecting comprises detecting a deflection via at least one of an amplitude change or a phase or time-delay change of a reflection of an acoustic signal reflected back from the acoustic redirection member to at least one of the acoustic transducers. In some other embodiments, the detecting comprises detecting a deflection via at least one of an amplitude change or a phase or time-delay change of a reflection of an acoustic signal reflected back from an acoustic reflection member to at least one of the acoustic transducers, the acoustic reflection member being mounted to the same portion of the distal member as the acoustic redirection member and partially reflecting the acoustic signal back to the at least one acoustic transducer. [0011] In specific embodiments, the acoustic monitoring method further comprises determining, based on a detected deflection and a related force-deflection relationship of the deflectable portion of the distal member, a force between the distal member and the biological member. The directing comprises at least one of: directing a first acoustic signal from a first acoustic transducer in a direction generally parallel to the longitudinal axis to the acoustic redirection member which redirects the first acoustic signal in a transverse direction nonparallel to the longitudinal axis to monitor a sideways-formed lesion; or directing a second acoustic signal from a second acoustic transducer in a forward direction generally parallel to the longitudinal axis to monitor a forward-facing lesion. Directing one or more acoustic signals to the biological member and receiving reflection echoes from the biological member by the one or more acoustic transducers comprises at least one of acoustic lesion feedback of the biological member being ablated, a tissue thickness measurement in a region of the biological member being ablated, a tissue proximity measurement in a region of the biological member being ablated, a pre-pop warning of the biological member being ablated, or a pre-pop detection of the biological member being ablated. [0012] These and other features and advantages of the present invention will become apparent to those of ordinary skill in the art in view of the following detailed description of the specific embodiments. BRIEF DESCRIPTION OF THE DRAWINGS [0013] FIG. 1A shows an inventive catheter tip region depicting ultrasonic lesion feedback plus simultaneous force measurement using the same transducer and acoustic mirror tip deflected upon endocardial tissue. [0014] FIG. 1B shows plots of axial and radial (angular) deflection versus detected acoustic reflection amplitude from the mirror. [0015] FIG. 2 is a schematic diagram of an ablation apparatus incorporating the ablation catheter tip of FIG. 1A . [0016] FIG. 3 shows another catheter tip region illustrating a dual transducer with forward and side looking ultrasonic lesion feedback and optional force detection. [0017] FIG. 4 shows an example of using two separate components for tissue images and deflections respectively. [0018] FIG. 5 shows another example of using two separate components for tissue images and deflections respectively. [0019] FIG. 6 shows an example of a mirror having a microstructured surface in the form of a three holes at the mirror periphery distributed about 120 degrees apart from each other. [0020] FIG. 7 shows an example of a mirror having a microstructured surface in the form of an array of holes along diagonal(s). DETAILED DESCRIPTION OF THE INVENTION [0021] In the following detailed description of the invention, reference is made to the accompanying drawings which form a part of the disclosure, and in which are shown by way of illustration, and not of limitation, exemplary embodiments by which the invention may be practiced. In the drawings, like numerals describe substantially similar components throughout the several views. Further, it should be noted that while the detailed description provides various exemplary embodiments, as described below and as illustrated in the drawings, the present invention is not limited to the embodiments described and illustrated herein, but can extend to other embodiments, as would be known or as would become known to those skilled in the art. Reference in the specification to “one embodiment,” “this embodiment,” or “these embodiments” means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment of the invention, and the appearances of these phrases in various places in the specification are not necessarily all referring to the same embodiment. Additionally, in the following detailed description, numerous specific details are set forth in order to provide a thorough understanding of the present invention. However, it will be apparent to one of ordinary skill in the art that these specific details may not all be needed to practice the present invention. In other circumstances, well-known structures, materials, circuits, processes and interfaces have not been described in detail, and/or may be illustrated in block diagram form, so as to not unnecessarily obscure the present invention. [0022] In the following description, relative orientation and placement terminology, such as the terms horizontal, vertical, left, right, top and bottom, is used. It will be appreciated that these terms refer to relative directions and placement in a two dimensional layout with respect to a given orientation of the layout. For a different orientation of the layout, different relative orientation and placement terms may be used to describe the same objects or operations. [0023] Exemplary embodiments of the invention, as will be described in greater detail below, provide apparatuses, methods and computer programs for ultrasonic lesion feedback, antipop monitoring, and net force magnitude and direction detection. [0024] Ultrasonic Feedback with Single Acoustic Transducer in Semi-Rigid Catheter Tip [0025] One aspect of this invention is to utilize an acoustic lesion feedback transducer to also measure distortions of a distortable tip having known (but very slight) spring behavior. How to do that for both axial and bending forces using a single spring is not obvious if one has in mind a very flexible tip made flexible to conform to tissue such as a Coolflex™ tip. Thus, tissue conforming tips teach away from the invention. [0026] Embodiments of the invention utilize a minimally flexible or semi-rigid tip (defined below) which is just flexible enough that its slight bending/compression with loading can be detected using a transducer/mirror arrangement; however, it is not so flexible that the ultrasonic beam angles between transducer and mirror change significantly (to a gross tissue conforming extent). In this way, one can track the force-induced slight axial compression and radial bending deflections as small time-delay changes (for axial deflections) and small reflection magnitude changes (for radial deflections). Further, one can retain in view, despite the deflections, the bulk of the tissue echogram coming from within the tissue which varies only with tissue necrosis or microbubbling. Note specifically that the semi-rigid tip is not useable to achieve gross tissue conformance. It will be apparent to one skilled in the art that angulating reflecting or redirecting mirrors will result in both time-delay changes and amplitude changes and these effects can combine to cause reflective peaks to both predictably broaden/narrow and/or to change amplitude depending on the geometries involved. [0027] It is critical that this catheter tip, to the human eye, is essentially rigid even though it will have laser cuts (or some other features of flexibility) which allow very slight distortions just large enough that they can be acoustically detected and correlated to a tiny deflection of a “stiff spring” section. We anticipate an angular distortion on the order of a degree or a few degrees (e.g., ±about 5 degrees) maximum and an axial distortion on the order of a fraction of a millimeter (e.g., a few hundred microns). [0028] In technical terms, the term “semi-rigid” means that one needs to use a deflection-detecting transducer which has a high enough frequency such that the maximum axial distortion is on the order of at least about a half wavelength. For example, one may use a transducer which is centered at about 10 MHz to about 16 MHz. For typical axial load ranges of about 5-50 grams, it may be desirable to have about a half wavelength of axial deflection, and for sideways radial loads of the same magnitude, it may be desirable to have angular distortions of about one degree or a few degrees. In a preferred embodiment, an A/D (analog-digital) digitizer has a minimum digitization rate of 100 MHz and a rate of about 200-500 MHz with at least effective 8-bits of amplitude resolution is preferred. The higher sampling frequency gives better time (versus sample amplitude) resolution so that one can detect small axial distortions causing time delay changes as well as small angular distortions causing mostly amplitude changes. [0029] FIG. 1A shows a sectional view of an ablation catheter according to an embodiment of the invention. The catheter includes a flexible body 1 d connected to an ablator tip 1 which has a rigid most-distal tip portion (acoustic mirror portion) 1 a including an acoustic reflection/redirection member (mirror, window, membrane) 2 , an intermediate more-proximal semi-rigid portion 1 b acting as a stiff spring, and a rigid most proximal tip portion 1 c . Ideally, the rigid most-distal portion 1 a has no internal axial deflection and no internal bending deflection (occurring within its own confines) and the rigid proximal tip portion 1 c has no internal axial deflection and no internal bending deflection (occurring within its own confines). All such bending and axial deflections are arranged to occur in the spring section 1 b (within its own confines) between the most-distal tip portion 1 a and the proximal tip portion 1 c . The mirror reflecting surface is typically metallic and the mirror can be nonfocusing or focusing. The ablator tip 1 may be an RF ablator tip wherein the most-distal portion 1 a is an RF electrode as the ablation member (e.g., made of metal such as a platinum alloy), or the ablator tip 1 may include one or more RF electrodes such as ring electrodes to provide RF ablation. [0030] In FIG. 1 a , the ablator tip 1 is depicted pressed into an endocardium 4 from a blood chamber 5 by the action of a contact force which generally will have a tangential component along the x-axis and a normal component along the y-axis. A directional (emitting in the −x direction here) ultrasonic transducer 3 is shown mounted in the rigid proximal tip portion 1 c . The transducer 3 produces acoustic signals such as acoustic beams or acoustic pings leftwards along a −x beam path off the mirror 2 into the tissue 4 to a tissue focus 7 and receives reflection echoes back from the tissue 4 , both defined by beam boundaries 6 a and 6 b . Note that the surface of the mirror 2 will slightly move/reorient relative to the transducer 3 upon tip loading because they are separated by the slightly flexible spring portion 1 b . FIG. 1A shows a slight bending of the tip, to an angle θ, perhaps a few degrees or so. A lesion 4 a is shown being formed in the tissue 4 as would be expected for an irrigated tip 1 with coolant saline 12 emanating from a beam port 11 . Thus, the spring deflections are only large enough to detect tip forces (axial x force, radial y force, and/or their vector sum and its angle to the tip long axis). The deflections are not large enough that the lesion feedback acoustic behavior is significantly different from that of a completely rigid acoustic transducer-mirror tip, i.e., the slight deflections do not shift the lesion feedback beam significantly. [0031] According to one configuration of the catheter device, a totally rigid side-fire mirror tip (no force capability) is capable of lesion feedback and has shown good tissue spectra upon lesioning. The device has a hole or port 11 out of which the beam 6 a / 6 b and the saline 12 emanate. That arrangement means that the RF lesion is formed primarily by the surrounding circumferential lip region of the most-distal tip portion 1 a defining the hole or port 11 and somewhat by the saline 12 emanating therefrom. That also means that the tissue being lesioned has a free underwater surface as opposed to a physically trapped cooled-ablator pressing upon it. That might undesirably allow for easier boiling. We have shown that an open port 11 can be made to work with sufficient irrigation flow; however, this disclosure also covers a port being a conductive impermeable or permeable membrane or window or mesh which can itself deliver some RF energy. A nonconductive membrane is also within the scope of this disclosure. [0032] The acoustic reflection/redirection member (mirror, window, or membrane) 2 and its movement relative to the transducer 3 form the force/deflection sensing mechanism. One preferred approach is the use of an angled (e.g., about 45 degrees as shown) acoustic mirror 2 stood off by a tip-internal saline cavity (between the mirror 2 and the transducer 3 ). We include in the scope of this disclosure the conditioning of the mirror (or membrane) surface (or bulk) such as by slight roughening, porosity or shaping so as to improve the mirror's acoustic visibility and response to orientation/position changes but not so much that we lose sensitivity otherwise useable for tissue reflections. The angled mirror, which is arranged to be nearly totally reflective (e.g., about 90-98%) but not 100% reflective, can thereby return both a virtually unaltered tissue reflection as well as a weaker tissue-nonobscuring reflection from the mirror itself. [0033] Alternatively one may provide the above mirror for tissue feedback and along the same beampath and also inside the tip also provide a low loss window, membrane, or prism of TPX polymer whose job it is to provide a normally orthogonal weak reflector to detect deflections. FIG. 4 shows an example of using two separate components for tissue images and deflections respectively. The ablator tip 1 uses the acoustic mirror 2 to redirect the acoustic signal from the transducer 3 for tissue images and uses another member 402 to detect deflections. The member 402 may be a membrane of TPX (polymethylpentene) polymer which is more than 90% transparent but not 100% transparent. The mirror 2 and the membrane 402 form an acoustic reflection/redirection member. FIG. 5 shows another example of using two separate components for tissue images and deflections respectively. The ablator tip 1 uses the acoustic mirror 2 to redirect the acoustic signal from the transducer 3 for tissue images and uses another member 502 to detect deflections. The member 502 may be a solid prism of TPX polymer which is more than 90% transparent but not 100% transparent. The mirror 2 and the prism 502 form an acoustic reflection/redirection member. [0034] The semi-rigid tip portion 1 b may be made in a manner somewhat similar to a lasered Coolflex™ tip (i.e., using Nitinol™ tubing and a laser beam cutter to form through-thickness cuts or partial-thickness cuts/grooves). In the example shown in FIG. 1A , multiple rows of circumferential cuts are staggered to form the semi-rigid tip portion 1 b . The major difference is that the laser cuts in this case are arranged to offer only very slight distortions (axial and/or angular) of the lasered member and are highly localized along the tip length dimension. The minimal distortion, semi-rigid spring member 1 b can be provided in multiple ways and the following are a few examples. Some of these do not even involve laser cutting. [0035] Approach 1—Use a laser machined metallic tube with significantly fewer laser cuts than a Coolflex™ flexible tip. The structure becomes much stiffer and acts as a stiff-spring to provide axial deflection of less than about 1 mm, preferably less than about 0.5 mm but more than about 0.125 mm and angular deflection of less than about ±10 degrees, preferably less than about ±5 degrees. Alternatively, the metallic tube may be machined in any manner such as by wet etching or EDM (electric discharge machining). [0036] Approach 2—Use cuts which do not overlap as much, thereby reducing cumulative distortion. The structure becomes much stiffer. [0037] Approach 3—Use a thicker tubing than a Coolflex™ flexible tip. The structure is linearly stiffer with increasing thickness approximately. [0038] Approach 4—Rather than laser cutting of tubing, use instead a convoluted or bellows-like tubular entity, whether metallic, ceramic, glass or polymeric (e.g., uncut bellows-like electrodeposited shell tips, wave washers). [0039] Approach 5—Make a flexible tip out of elastic braid to form a braided or woven tube, a mesh structure, a honeycombed sheet, or a polymeric tube. A tube is a body having an interior cavity, two open opposed ends, a length, and a cross-sectional shape mountable in or on the tip, the cross-sectional shape not necessarily round. [0040] In FIG. 1A , the mirror 2 is mounted in the most distal rigid tip portion 1 a and the transducer 3 is mounted in the proximal rigid tip portion 1 c . In another embodiment, the transducer 3 is mounted in the most distal rigid tip portion 1 a and the acoustic reflection/redirection member (mirror, window, or membrane) is mounted at the proximal rigid tip portion 1 c or at the more proximal end of at least some of the connected semi-rigid deflectable portion 1 b , the acoustic beam or ping traveling through the interior space of at least some of the deflectable semi-rigid portion 1 b . The space for the acoustic path of the beam between the acoustic reflection/redirection member 2 and the transducer 3 includes or is filled with a flowable or deflectable low-acoustic-attenuation material such as saline or a low loss polymer such as a urethane or TPX or a combination thereof. [0041] Typically, an operating transducer frequency of the transducer 3 is in the range of about 2 to 50 MHz with a preferred frequency in the range of about 10 to 30 MHz as a tradeoff between axial resolution and manufacturability. RF ablation and ultrasonic pinging are arranged to occur substantially separately in time to avoid their interfering with each other. Any one or more of RF ablation or ultrasonic pinging may be synchronized or gated using a biological signal such as an ECG or EGM signal in addition to or instead of being synched to each other directly. [0042] An example of the acoustics amplitude and/or time-phase variation versus tip forces is shown in FIG. 1B . The axial force component upon the tip along the ±x axis is the easiest to describe. Essentially any acoustic spectrum feature which occurs at a point in time will be shifted by Δt (see shifting of graph 8 in FIG. 1B ) by the application of the axial force component. This is simply because the transducer 3 is either slightly closer to or slightly further from the mirror 2 (whose own reflection can be seen independent of the tissue reflections) for compression and tension tip loads, respectively. This phenomenon will take place even if there is also a few degree angular A for bending. The bending reflection variation behavior is approximately shown as a plot 9 at a particular axial deflection. Essentially over the narrow allowable 0-70 gram 0-5 degree or so bending range, the behavior will be slightly curvilinear as depicted. Although in the actual case, both axial and bending forces are simultaneously applied, what is occurring is that because of the heartbeat and/or breathing cycle, we will, over the time of seconds, be essentially plotting a back and forth orbital path such as the repeating path 13 shown in FIG. 1B . We anticipate that having that path information will allow us to deconvolute the axial and radial deflection components whatever combination they take. The transducer 3 can detect the deflection (axial and angular) via at least one of amplitude change or phase change of reflection of an acoustic signal reflected back from the acoustic reflection/redirection member 2 . In a preferred embodiment, the mirror angulation itself causes minimal time-delay change (but a large amplitude change) and if desired, by knowing the amplitude change (and bending degree), one can actually subtract out the minimal time-delay change due to bending such that all remaining time delay change is due to axial deflection. The inventors have demonstrated this ability albeit the correction is small. [0043] In US2012/0265069 (which is incorporated herein by reference in its entirety), we taught an acoustically transparent RF tip made substantially entirely of carbon (e.g., at least about 90% carbon by volume) having an acoustic impedance between that of the transducer and that of the tissue. As applied in this case, the rigid most-distal portion 1 a may be carbon based such that there is no need for an open port 11 , resulting in the delivery of uniform RF. One would still have irrigated saline very close by or upon the heated tissue surface. Furthermore, the mirror 2 , with a carbon tip portion 1 a , may be a thinfilm metal-on-carbon laminate. [0044] The catheter provides ablation capability in addition to at least one of (a) data regarding a formed or forming lesion, (b) data regarding an interface or tissue thickness, (c) data regarding a degree of transmurality of a lesion in a tissue layer, and (d) data regarding potential or actual pop activity. Either of lesion-feedback or pop potential is detected acoustically by an acoustic beam which enters tissue through the acoustic reflection/redirection member 2 (mirror, window or membrane) or an open hole or port 11 in the tip 1 . Furthermore, (i) any one or more of force, a lesion progress parameter or a pop parameter are reported to the user in any form; (ii) any one or more of force, a lesion progress parameter or a pop parameter are internally utilized by the system in any form; and (iii) any one or more of force, a lesion progress parameter or a pop parameter are recorded or remotely communicated in any form. By allowing the acoustic beam or ping to enter tissue, the system also or instead reports or utilizes any one or more of: (i) lesioning behavior or state, (ii) prepop behavior or state, and (iii) proximity or orientation to tissue. Any one or more of the force, pop or lesion-feedback capabilities may be activated and/or deactivated via software uploads, network communications, or customer input, whether by the system user, by a connected system or network or by a remote support person. Any one or more of force, a lesion progress parameter, or a pop parameter may be utilized as feedback to the system or user for a control, safety, or logging reason. [0045] If a customer has possession of a transducer-bearing catheter, we can provide or activate software, even remotely, which can perform any one or more of: (a) reporting force, (b) providing anti-pop monitoring, and (c) reporting lesion depth. Since upon pinging we get all the information pertaining to the tissue and the moving mirror, we are not adding anything to procedure time. The algorithm to do the distortion measurement (force measurement) is actually much simpler than the lesion-depth algorithm or the anti-pop algorithm. We can provide software upgrade on-demand at the moment the practitioner decides he/she wants that modality. It would be turned on and charged to the customer's account at the same time. [0046] We stated that macroscopically conforming lasered bending tips teach away from the present invention. That is because if one simply puts the inventive transducer and mirror on the opposite (far) end of such a flexible laser tip, the tissue-conformance bending is so large (tens of degrees bending sometimes) that it would be very difficult to retain a reasonable tissue-echo spectrum from the tissue or, for that matter, any echo off the mirror back to the transducer over such a huge range. Although one could put the transducer and mirror closer together to overcome this issue, when one does that, one is removing some of the useful standoff distance which allows easy identification of the mirror echo beyond the transducer ringing noise. However the invention is not fundamentally incompatible with highly conforming macroscopically bending tips. By placing the mirror closer to the transducer, one could tolerate more tip bending as long as the transducer employed has a short enough ringdown. [0047] We also include in the scope of this invention the mirror 2 (or window or membrane) having a microstructured surface such as that made by laser machining or etching. The idea is to place features on/in the mirror surface either locally or across the mirror face (a) which do not substantially interfere with tissue echoes such as by consuming only a very small percentage of the area of the mirror (e.g., a few percent at the midregion for example) and (b) which enhance the changes in acoustic reflection behavior (amplitude and/or phase) with mirror tilting and/or axial motion. For example, one could laser drill an array of holes at ever increasing angles from 90 degrees into the mirror surface. The ability to acoustically “see” the bottoms of the various holes depends on whether that particular angled hole is “pointing” at the transducer at that particular state of bending load. Such a hole array could be placed in the central mirror region and/or concentrated upon a few radial lines running from mirror center to edge. FIG. 6 shows an example of a mirror 2 having a microstructured surface in the form of a three holes at the mirror periphery distributed about 120 degrees apart from each other. FIG. 7 shows an example of a mirror 2 having a microstructured surface in the form of an array of holes along diagonal(s). The holes come/go from acoustic view versus tilt angle. The hole bottoms provide strong orthogonal reflectors at zero degrees. Varying hole depth could allow identification of any specific hole. [0048] The mirror 2 (or window or membrane) may also be focusing or refracting of acoustics wherein the acoustic reflections from the mirror vary with angle as the reflection/focus/refraction behavior versus angle systematically changes. [0049] One feature the invention is a combined acoustic and optical solution wherein the acoustics do the lesion feedback, the antipop monitoring, and only the axial part of force detection. The mirror is optically coated with an optical interference film system such that its optical reflectivity (or reflected color) changes with mirror tilt angle. In this case, a small optical fiber/optical lens/light source would illuminate the mirror likely in the middle from a standoff distance larger than the maximum tip compression. The reflected light would be analyzed for color and/or amplitude. Thus we get bending force optically from the mirror and we get axial force acoustically from the mirror. [0050] We again expect and know that when an intracardiac or other therapeutic or diagnostic catheter is in the body that the heartbeat motion, the blood flow and the breathing of the patient all cause periodic variations in catheter tip contact angle and force. We include here in our inventive scope, most particularly for those applications involving lesion or pop feedback, the recording or use of known instrumented breathing rates and heartbeat rates in order to account for their effects upon echograms. For example, echograms could be time-sampled based on the heartbeat deduced from the cyclic force data thereby obtaining echograms at known heartbeat phase angles. As an alternative one can record enough echograms often enough so that such periodicities can be discovered purely from the echogram data and the appropriate compensations made therefore. [0051] FIG. 2 is a schematic diagram of an ablation apparatus incorporating the ablation catheter tip of this disclosure. An ablation catheter 110 includes a control handle 116 , and an elongated catheter body 112 having a distal region 114 adjacent a distal end 118 . The distal region 114 includes any of the ablation tips shown and described herein (e.g., ablator tip 1 in FIG. 1A or ablating tip 302 in FIG. 3 ). The catheter 110 is connected with an ablation energy source 120 such as an RF generator, and with an irrigation fluid source 124 to provide an irrigation and tip-cooling fluid. A transducer pinger 128 , which might have more than one channel, transmits and receives pinging energy such as that delivered to or received from acoustic transducer(s) (e.g., 3 in FIG. 1A or 305 a and 305 b in FIG. 3 ). A control unit or controller 130 is provided for controlling the ablation and the acoustic pinging during ablation. For instance, the control unit 130 is configured to carry out the duty cycles for ablation and pinging. An acoustic pinger echo analyzer 132 is provided to analyze the data collected (e.g., by a software or firmware algorithm) from the acoustic transducer(s) to provide one or more of lesion feedback, tissue thickness or proximity measurement, tip contact force monitoring, and pre-pop detection. The information is preferably presented to the operator (e.g., using a graphical user interface) to provide real time assessment of the ablation. The information may additionally or alternatively be utilized by the system itself without operator intervention. Based on a detected deflection and a related force-deflection relationship of the deflectable spring portion 1 b , the control unit 130 can determine the force between the distal tip 1 and the biological member such as the endocardium 4 . [0052] Ultrasonic Feedback with Forward and Side Looking Acoustic Transducers in Semirigid Catheter Tip [0053] FIG. 3 shows another catheter tip region illustrating a dual transducer with forward and side looking ultrasonic lesion feedback and optional force detection. FIG. 3 shows an RF ablation catheter 301 having an ablating tip 302 distally mounted on a flexible catheter body 303 having a lumen. The catheter 301 is shown immersed in blood 311 such as within a heart chamber or some other biological member. The catheter ablation tip portion 302 is depicted resting against a myocardial or ventricular wall 310 which is to receive a lesion 312 . It will be noted that the distal tip portion 302 contains a dual ultrasonic transducer 305 capable of either or both of pinging forwardly along the −x direction or downwardly (sideways via mirror 307 redirection) in the −y direction. The transducer 305 has a shared common attenuative backer material portion 305 c on which are mounted opposed piezotransducers 305 a (forward looking) and 305 b (side looking via redirecting acoustic mirror 307 ). Because the transducer piezoelements 305 a / 305 b both share the same attenuative backer 305 c , we save space inside the tip 302 . The forward firing transducer 305 a forms a beam defined by beam outline 308 a / 308 b which comes to a forward focus at point 308 also labeled as F f . That forward beam passes through a window or hole in the tip body in order to pass to focus 308 . The side-firing (via mirror 307 ) transducer 305 b forms a beam which is redirected sideways (−y direction) in the form of outline 309 a / 309 b and coming to a focus at point 309 also labeled as point F s . The acoustic mirror 307 , such as a stainless mirror, is depicted to have a 45 degree angle relative to the x-axis such that it redirects the sidefire beam 309 a / 309 b approximately at a right angle out of the tip 302 into the target tissue 310 . [0054] It will be noted in FIG. 3 that the forward-firing beam 308 a / 308 b travels through saline 306 a or other acoustically transparent material (such as urethane, silicone, or TPX) before emanating forwardly generally along the longitudinal axis to focus point 308 . Likewise, sidefire beam 309 a / 309 b travels through saline or other acoustically transparent material 306 b before emanating sideways in a beam emanation direction to focus point 309 (F s ). In a preferred embodiment, materials 306 a and 306 b are saline which is passed through the tip 302 also for cooling purposes (such as for tissue surface cooling/irrigation and/or tip cooling). Included within the inventive scope is having portions of the saline filled region instead or partly filled with the aforementioned transparent, nonfluid, flexible or rigid materials such as urethane, silicone, or TPX. [0055] The distal ablating tip 302 includes a first ultrasonic transducer 305 a oriented to give a tip-forward view of target tissue 310 (in the forward direction along the longitudinal axis, when the tip is end-on to tissue) and a second ultrasonic transducer 305 b oriented to give a tip-sideways view of target tissue 310 (acoustic signal being redirected in a transverse direction nonparallel to the longitudinal axis and typically substantially perpendicular to the longitudinal axis) as shown in FIG. 3 . At least one of the transducers ( 305 b ) directs its acoustic beam upon the acoustic redirection mirror 307 which redirects the acoustic beam to achieve its sideways view of target tissue 310 . The transducer 305 b and the acoustic mirror 307 are situated on opposite sides of a tip spring member 304 of known stiffness which distorts in response to a tip load causing an angle and/or distance between the transducer 305 b and the mirror 307 to vary with the tip force, the distortions (bending and axial) each being acoustically detectable and accompanied by a corresponding tip force component. In FIG. 3 , the dual transducers 305 are mounted to a rigid most-distal tip portion 302 a while the mirror 307 is mounted to a rigid proximal tip portion 302 b . The two transducers 305 a , 305 b are mounted in an opposed fashion such that they share a common attenuative backer 305 c rather than separate backers which would take more space. Each of the transducers is separately operable via its own electrical interconnections (not shown). [0056] As seen in FIG. 3 , the distal tip 302 has lasered slits or slots cut into it at a localized axial location to form an intermediate semi-rigid spring portion 304 . These slots act as a stiff spring such that the more distal tip portion 302 a can slightly deflect angularly with respect to the more proximal tip portion 302 b such as around one or both of the y-axis and/or z-axis. The semi-rigid portion 304 may also/instead allow some stiff axial deformation axially along the x-axis. By stiff we mean that typical tip loads in the range of about 10-100 grams will bend the most-distal tip portion 302 a relative to the proximal tip portion 302 b just a few degrees at most (less than about 10 degrees, preferably less than about 5 degrees). In this manner, even when bent by a tip-load, the side-fire beam 309 a / 309 b can still echogenically view the tissue. The same can be said for any axial deflection of the stiff spring 304 in that it may be limited to a fraction of a millimeter or even less (less than 1 mm, preferably less than about 0.5 mm), as long as it is acoustically detectable as a moved reflection in the time domain. In specific embodiments, the axial deflection is less than about 1 mm under an axial force of less than about 100 grams. The bending deflection is less than about 10 degrees under a bending moment of about 200 gram-millimeters (e.g., 100 grams applied at 2 mm moment arm distance from the tip spring member 304 , 2 mm being the likely length of the most-distal tip portion 302 a ). [0057] As taught in the earlier disclosure, one monitors the echo reflections from the surface of the mirror 307 in order to deduce and back-compute deflections of the stiff spring 304 . Two or more deflections may be evaluated in order to provide a vector sum and subcomponents of the net vector sum tip force. The mirror echoes are preferably significantly weaker (e.g., 5-20 times) than the tissue echoes and arrive at an earlier time so that they can be differentiated from each other. [0058] In the typical case the practitioner or doctor would, at a given moment, be using either the forward firing or the side firing transducer depending on which has the best view of the tissue portion to be lesioned. In FIG. 3 , the lesion 312 is best viewed by the side-firing transducer 305 b and its redirected beam 309 a / 309 b . The lesion 312 is regarded as a sideways lesion as opposed to an end-on lesion. The system used to control the catheter could automatically acoustically recognize that there is tissue in front of (in the beamline of) a given transducer 305 a or 305 b and switch over to that transducer. [0059] The described embodiments, as those familiar with acoustics will recognize, typically have the mirror or mirror and window/membrane in the near-field of the transducer beam pattern. Inventors explicitly include in their scope embodiments operating in the beams far-field as well. It will be appreciated that near-field operation may allow for a shorter tip which is preferable. [0060] Herein we have taken the liberty of giving force as grams which is often done for tip forces; however, the astute and technically correct reader will understand that such practitioners mean grams-force and not grams-mass. That is, the force or weight of a 1 gram mass is one gram-force in earth gravity. [0061] While specific embodiments have been illustrated and described in this specification, those of ordinary skill in the art appreciate that any arrangement that is calculated to achieve the same purpose may be substituted for the specific embodiments disclosed. This disclosure is intended to cover any and all adaptations or variations of the present invention, and it is to be understood that the terms used in the following claims should not be construed to limit the invention to the specific embodiments disclosed in the specification. Rather, the scope of the invention is to be determined entirely by the following claims, which are to be construed in accordance with the established doctrines of claim interpretation, along with the full range of equivalents to which such claims are entitled.

An ablation catheter comprises: an elongated catheter body extending longitudinally between a proximal end and a distal end along a longitudinal axis; a distal member disposed adjacent the distal end, the distal member including an ablation element to ablate a biological member; one or more acoustic transducers disposed in the distal member and each configured to direct an acoustic signal toward a respective target ablation region and receive reflection echoes therefrom; and an acoustic redirection member disposed in the distal member to at least partially redirect the acoustic signal from at least one of the acoustic transducers toward a tissue target. The distal member includes a most-distal portion, a proximal portion, and a deflectable portion between the most-distal portion and proximal portion to permit deflection between the most-distal portion and proximal portion of the distal member. The transducers and redirection member are mounted on opposite sides of the deflectable portion.

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates in general to a seat mounting arrangement for a motor vehicle, and more particularly to a seat mounting arrangement for use with a motor vehicle equipped with a safety seat belt. 2. Description of the Prior Art In passenger motor vehicles, various kinds of seat mounting arrangements have been proposed and put into practical use for mounting a passenger seat on a vehicle floor. In a case wherein a seat belt is incorporated therewith, the arrangement becomes complicated in construction because it must bear against an abnormally big shock or impact force which, upon a vehicle collision, is applied thereto through a seat belt wearer on the seat. Usually, the arrangement uses several supporting brackets for supporting the seat on the vehicle floor, so that, upon vehicle collision, the impact force applied thereto is dispersed or transmitted to the vehicle floor through the brackets. However, hitherto, construction and disposition of the brackets have been given little thought. Thus, some of the conventional seat mounting arrangements have suffered from several drawbacks, such as, insufficient strength against abnormal shock, poor external appearance, troublesome assembling work and so on. SUMMARY OF THE INVENTION It is therefore an object of the present invention to provide a seat mounting arrangement which is characterized by sufficient strength against shock of large magnitude, good appearance and easy assembling work. According to the present invention, there is provided an improved seat mounting arrangement incorporated with a seat belt assembly, the seat mounting arrangement comprising a seat sliding mechanism including first and second assemblies or groups of parts, each group including a stationary rail connected to the vehicle floor and a slide rail secured to the seat and slidable on the stationary rail, so that the seat is slidable relative to the vehicle floor, the first group being located adjacent the vehicle floor tunnel; first and second brackets secured to longitudinally spaced portions of the stationary rail of the first group and connected to the vehicle floor; third and fourth brackets secured to longitudinally spaced portions of the stationary rail of the second group and connected to the vehicle floor, wherein one of the first and second brackets comprises a toughly constructed support member which transversely straddles the floor tunnel and is bolted to the same, the support member comprising a center portion at opposite longitudinal ends of the support member bolted to the floor tunnel and two wing portions extending in the opposite directions from the center portion, one of the wing portions supporting thereon the associated stationary rail and secured to the same. BRIEF DESCRIPTION OF THE DRAWINGS Other objects and advantages of the present invention will become apparent from the following description when taken in conjunction with the accompanying drawings, in which: FIG. 1 is a partially broken perspective view of a seat mounting arrangement of a first embodiment of the present invention; FIG. 2 is an enlarged view of an essential part of the seat mounting arrangement, which is taken from the direction of the arrow "II" of FIG. 1; FIG. 3 is a perspective view of an inboard group of parts of a seat sliding mechanism employed in the first embodiment; FIG. 4 is a side view of the inboard group of parts of the seat sliding mechanism, which is taken from the direction of the arrow "IV" of FIG. 3; and FIG. 5 is a view similar to FIG. 1, but showing a seat belt anchor stay which is to be mounted to a floor tunnel. DESCRIPTION OF THE INVENTION Referring to FIGS. 1 to 4, particularly FIG. 1, there is shown a driver's seat 10 which is incorporated with a seat mounting arrangement of the present invention. The seat 10 is mounted on a seat sliding mechanism 12 so that the seat 10 is movable in the fore-and-aft direction relative to a vehicle floor 14. The seat sliding mechanism 12 comprises an inboard or first group of parts 12A and an outboard or second group of parts 12B each including a stationary rail 16 connected to the vehicle floor 14 and a slide rail 20 secured to the seat 10 and slidable on the stationary rail 16. The stationary rail 16 of the outboard group 12B is supported at its front and rear ends by suitable brackets 18 secured to the vehicle floor 14. The manner in which the stationary rail 16 of the inboard group 12A is connected to the vehicle floor 14 will be described hereinafter. As is seen from FIGS. 2 and 3, the inboard group 12A (that is, the group located near a floor tunnel 22 as shown in FIG. 1) further comprises an upper plate 24 which is interposed between the slide rail 20 and the seat 10 and a side plate 26 which is secured or welded to an upwardly extending flange portion 24a of the upper plate 24. As is best seen from FIG. 3, the side plate 26 is formed at its rear portion with a rounded lug 26a to which a nut 28 is secured or welded. As is seen from FIG. 2, the side plate 26 is formed at its lower section with an upwardly curved portion 26a which extends longitudinally. The inboard group 12A of the seat sliding mechanism 12 further comprises a lower plate 30 which is secured to the stationary rail 16. As will be described in detail hereinafter, the lower plate 30 is connected to the floor tunnel 22 through a toughly constructed bracket (38). The lower plate 30 has at its inboard side a raised portion which is formed at its upper section with a downwardly curved portion 30a which extends longitudinally. The upwardly curved portion 26a of the side plate 26 and the downwardly curved portion 30a of the lower plate 30 are slidably and interlockably engaged, as is seen from FIG. 2. The lower plate 30 is formed at its outboard side with a plurality of longitudinally aligned teeth 30b. As is seen from FIG. 2, the upper plate 24 is equipped at its outboard side with a locking pawl 32 which is pivotally connected thereto. A spring (not shown) is incorporated with the locking pawl 32 to bias the same to pivot toward the teeth 30b of the lower plate 30, that is, in the direction to engage with one of the teeth 30b. A lock lever 34 is connected to the locking pawl 32 to move therewith. As is seen from FIG. 4, the lock lever 34 extends toward the front portion of the seat 10 and is equipped with a control knob 35. When, thus, the locking pawl 32 is disengaged from the teeth 30b by handling the control knob 35, the slide rails 20 and thus the seat 10 can slide along the stationary rails 16. When, on the contrary, the locking pawl 32 is brought into locking engagement with one of the teeth 30b of the lower plate 30 with the aid of the biasing force of the spring, the slide rail 20 is locked to the stationary rail 16. With this operation, position adjustment of the seat 10 relative to the vehicle floor 14 is achieved. Designated by numeral 36 in FIG. 1 is a cross member which is securedly mounted on the vehicle floor 14 and extends across the same straddling the floor tunnel 22. As is seen from FIG. 4, a front bracket l8a is connected to a front portion of the lower plate 30. The front bracket l8a is secured at its lower end to the cross member 36. For this connection, the cross member 36 is formed with a nut-mounted opening 36a to which a connecting bolt (not shown) from the bracket l8a is engaged. Is the rear of the cross member 36, there is provided a toughly constructed main bracket 38 which is bolted to the top of the floor tunnel 22 by a connecting bolt 40. The main bracket 38 comprises a raised center portion 38a bolted to the floor tunnel 22 and two wing portions 38b (only one wing portion is shown in the drawing) extending in the opposite directions from the center portion 38a. Each wing portion 38b is formed with a nut-mounted opening 38c. For increasing the mechanical strength, the bracket 38 is pressed to have stopped portions, as shown. Upon properly mounting of the seat 10 on the vehicle floor 14, the lower plate 30 of the seat sliding mechanism 12A is placed on the wing portion 38b of the main bracket 38 and a connecting bolt 42 (See FIG. 2) extending through the lower plate 30 is engaged with the opening 38c. For this connection, as is seen from FIG. 3, the stationary rail 16 and the lower plate 30 are formed with mated openings (no numerals) through which the connecting bolt 42 passes. Although not shown in the drawings, the left wing portion of the main bracket 38 supports an inboard group of parts of a sliding mechanism of another seat (forward passenger seat) in substantially the same manner as that mentioned hereinabove. As is seen from FIG. 3, an extra or sub-bracket 44 is secured or welded to the raised center portion of the lower plate 30 and extends rearwardly downwardly with respect to the longitudinal axis of the stationary rail 16. The sub-bracket or fifth bracket 44 is formed with an opening 44a at its lower portion. As is understood from FIG. 1, upon mounting of the seat 10 onto the vehicle floor 14, the sub-bracket 44 is placed on one side wall 22a of the floor tunnel 22 at a position behind the main bracket 38 and connected to the same. For this connection, the side wall 22a is formed with a nut-mounted opening 22b to which a connecting bolt 46 from the sub-bracket 44 is engaged. For reinforcing the area where the opening 22b is located, a reinforcing plate 47 is attached to the back side of the side wall 22a, as shown. Designated by numeral 48 in FIG. 1 is an anchor stay for use with a safety seat belt (not shown). The anchor stay 48 carries thereon a catch member 48a of a known buckle assembly. As is seen from FIGS. 2 and 3, the anchor stay 48 is pivotally connected to the rounded lug 26a of the side plate 26 of the seat sliding mechanism 12A. For this connection, a connecting bolt 50 passes through an opening 48b of the anchor stay 48 and engages with the nut-mounted opening 28 of the rounded lug 26a. Thus, the anchor stay 48 moves together with the seat 10. FIG. 5 shows a case wherein the anchor stay 48 is connected to the floor tunnel 22. In this case, the sub-bracket 44 and its associated parts, such as the side plate 26 and the raised portion of the lower plate 30 are unnecessary, as is understood from this drawing. With the seat mounting arrangements of the present invention as described hereinabove, the following advantages are obtained, which are: (1) Since the main bracket 38 having a tough or sturdy construction is used for supporting the portion of the seat to which an abnormally large force is applied upon a vehicle collision, the safety of the seat occupant is assured. (2) Since the main bracket 38 is connected to the top of the floor tunnel 22 keeping a considerable space between each wing portion 38b of the bracket 38 and the vehicle floor 14, enlarged foot space for a passenger seated behind the seat 10 is obtained. (3) Since the main bracket 38 is arranged to equally support two seats by its wing portions 38b, balanced supporting of the seats is achieved. (4) Since the main bracket 38 is connected to the floor tunnel 22 with its wing portions 38b exposed to the interior of the vehicle, mounting and bolting the inboard assembly or group of parts 12A of the seat sliding mechanism 12 to the bracket 38 is accomplished with ease.

In a motor vehicle having a seat belt which is incorporated with a position adjustable passenger seat, there is proposed an improved seat mounting arrangement for safely supporting the seat even upon a vehicle collision. For this, a toughly constructed bracket member is employed which is connected to a floor tunnel and supports thereon a stationary member of a seat sliding mechanism.

REFERENCE TO PENDING PRIOR PATENT APPLICATIONS [0001] This patent application claims benefit of: [0002] (i) pending prior U.S. Provisional Patent Application Ser. No. 61/210,315, filed Mar. 17, 2009 by Julian Nikolchev et al. for JOINT SPACING BALLOON CATHETER (Attorney's Docket No. FIAN-28 PROV); [0003] (ii) pending prior U.S. Provisional Patent Application Ser. No. 61/268,340, filed Jun. 11, 2009 by Julian Nikolchev et al. for METHOD AND APPARATUS FOR DISTRACTING A JOINT, INCLUDING THE PROVISION AND USE OF A NOVEL JOINT-SPACING BALLOON CATHETER AND A NOVEL INFLATABLE PERINEAL POST (Attorney's Docket No. FIAN-42 PROV); [0004] (iii) pending prior U.S. Provisional Patent Application Ser. No. 61/278,744, filed Oct. 9, 2009 by Julian Nikolchev et al. for METHOD AND APPARATUS FOR DISTRACTING A JOINT, INCLUDING THE PROVISION AND USE OF A NOVEL JOINT-SPACING BALLOON CATHETER AND A NOVEL INFLATABLE PERINEAL POST (Attorney's Docket No. FIAN-49 PROV); and [0005] (iv) pending prior U.S. Provisional Patent Application Ser. No. 61/336,284, filed Jan. 20, 2010 by Julian Nikolchev et al. for METHOD AND APPARATUS FOR DISTRACTING A JOINT, INCLUDING THE PROVISION AND USE OF A NOVEL JOINT-SPACING BALLOON CATHETER AND A NOVEL INFLATABLE PERINEAL POST (Attorney's Docket No. FIAN-53 PROV). [0006] The four (4) above-identified patent applications are hereby incorporated herein by reference. FIELD OF THE INVENTION [0007] This invention relates to surgical methods and apparatus in general, and more particularly to methods and apparatus for treating a hip joint. BACKGROUND OF THE INVENTION The Hip Joint in General [0008] The hip joint is a ball-and-socket joint which movably connects the leg to the torso. The hip joint is capable of a wide range of different motions, e.g., flexion and extension, abduction and adduction, medial and lateral rotation, etc. See FIGS. 1A , 1 B, 1 C and 1 D. [0009] With the possible exception of the shoulder joint, the hip joint is perhaps the most mobile joint in the body. Significantly, and unlike the shoulder joint, the hip joint carries substantial weight loads during most of the day, in both static (e.g., standing and sitting) and dynamic (e.g., walking and running) conditions. [0010] The hip joint is susceptible to a number of different pathologies. These pathologies can have both congenital and injury-related origins. In some cases, the pathology can be substantial at the outset. In other cases, the pathology may be minor at the outset but, if left untreated, may worsen over time. More particularly, in many cases, an existing pathology may be exacerbated by the dynamic nature of the hip joint and the substantial weight loads imposed on the hip joint. [0011] The pathology may, either initially or thereafter, significantly interfere with patient comfort and lifestyle. In some cases, the pathology can be so severe as to require partial or total hip replacement. A number of procedures have been developed for treating hip pathologies short of partial or total hip replacement, but these procedures are generally limited in scope due to the significant difficulties associated with treating the hip joint. [0012] A better understanding of various hip joint pathologies, and also the current limitations associated with their treatment, can be gained from a more thorough understanding of the anatomy of the hip joint. Anatomy of the Hip Joint [0013] The hip joint is formed at the junction of the leg and the hip. More particularly, and looking now at FIG. 2 , the head of the femur is received in the acetabular cup of the hip, with a plurality of ligaments and other soft tissue serving to hold the bones in articulating condition. [0014] More particularly, and looking now at FIG. 3 , the femur is generally characterized by an elongated body terminating, at its top end, in an angled neck which supports a hemispherical head (also sometimes referred to as “the ball”). As seen in FIGS. 3 and 4 , a large projection known as the greater trochanter protrudes laterally and posteriorly from the elongated body adjacent to the neck of the femur. A second, somewhat smaller projection known as the lesser trochanter protrudes medially and posteriorly from the elongated body adjacent to the neck. An intertrochanteric crest ( FIGS. 3 and 4 ) extends along the periphery of the femur, between the greater trochanter and the lesser trochanter. [0015] Looking next at FIG. 5 , the hip socket is made up of three constituent bones: the ilium, the ischium and the pubis. These three bones cooperate with one another (they typically ossify into a single “hip bone” structure by the age of 25 or so) in order to collectively form the acetabular cup. The acetabular cup receives the head of the femur. [0016] Both the head of the femur and the acetabular cup are covered with a layer of articular cartilage which protects the underlying bone and facilitates motion. See FIG. 6 . [0017] Various ligaments and soft tissue serve to hold the ball of the femur in place within the acetabular cup. More particularly, and looking now at FIGS. 7 and 8 , the ligamentum teres extends between the ball of the femur and the base of the acetabular cup. As seen in FIGS. 8 and 9 , a labrum is disposed about the perimeter of the acetabular cup. The labrum serves to increase the depth of the acetabular cup and effectively establishes a suction seal between the ball of the femur and the rim of the acetabular cup, thereby helping to hold the head of the femur in the acetabular cup. In addition to the foregoing, and looking now at FIG. 10 , a fibrous capsule extends between the neck of the femur and the rim of the acetabular cup, effectively sealing off the ball-and-socket members of the hip joint from the remainder of the body. The foregoing structures (i.e., the ligamentum teres, the labrum and the fibrous capsule) are encompassed and reinforced by a set of three main ligaments (i.e., the iliofemoral ligament, the ischiofemoral ligament and the pubofemoral ligament) which extend between the femur and the perimeter of the hip socket. See, for example, FIGS. 11 and 12 , which show the iliofemoral ligament, with FIG. 11 being an anterior view and FIG. 12 being a posterior view. Pathologies of the Hip Joint [0018] As noted above, the hip joint is susceptible to a number of different pathologies. These pathologies can have both congenital and injury-related origins. [0019] By way of example but not limitation, one important type of congenital pathology of the hip joint involves impingement between the neck of the femur and the rim of the acetabular cup. In some cases, and looking now at FIG. 13 , this impingement can occur due to irregularities in the geometry of the femur. This type of impingement is sometimes referred to as cam-type femoroacetabular impingement (i.e., cam-type FAI). In other cases, and looking now at FIG. 14 , the impingement can occur due to irregularities in the geometry of the acetabular cup. This latter type of impingement is sometimes referred to as pincer-type femoroacetabular impingement (i.e., pincer-type FAI). Impingement can result in a reduced range of motion, substantial pain and, in some cases, significant deterioration of the hip joint. [0020] By way of further example but not limitation, another important type of congenital pathology of the hip joint involves defects in the articular surface of the ball and/or the articular surface of the acetabular cup. Defects of this type sometimes start out fairly small but often increase in size over time, generally due to the dynamic nature of the hip joint and also due to the weight-bearing nature of the hip joint. Articular defects can result in substantial pain, induce and/or exacerbate arthritic conditions and, in some cases, cause significant deterioration of the hip joint. [0021] By way of further example but not limitation, one important type of injury-related pathology of the hip joint involves trauma to the labrum. More particularly, in many cases, an accident or sports-related injury can result in the labrum being torn away from the rim of the acetabular cup, typically with a tear running through the body of the labrum. See FIG. 15 . These types of injuries can be very painful for the patient and, if left untreated, can lead to substantial deterioration of the hip joint. The General Trend Toward Treating Joint Pathologies Using Minimally-Invasive, and Earlier, Interventions [0022] The current trend in orthopedic surgery is to treat joint pathologies using minimally-invasive techniques. Such minimally-invasive, “keyhole” surgeries generally offer numerous advantages over traditional, “open” surgeries, including reduced trauma to tissue, less pain for the patient, faster recuperation times, etc. [0023] By way of example but not limitation, it is common to re-attach ligaments in the shoulder joint using minimally-invasive, “keyhole” techniques which do not require laying open the capsule of the shoulder joint. By way of further example but not limitation, it is common to repair torn meniscal cartilage in the knee joint, and/or to replace ruptured ACL ligaments in the knee joint, using minimally-invasive techniques. [0024] While such minimally-invasive approaches can require additional training on the part of the surgeon, such procedures generally offer substantial advantages for the patient and have now become the standard of care for many shoulder joint and knee joint pathologies. [0025] In addition to the foregoing, in view of the inherent advantages and widespread availability of minimally-invasive approaches for treating pathologies of the shoulder joint and knee joint, the current trend is to provide such treatment much earlier in the lifecycle of the pathology, so as to address patient pain as soon as possible and so as to minimize any exacerbation of the pathology itself. This is in marked contrast to traditional surgical practices, which have generally dictated postponing surgical procedures as long as possible so as to spare the patient from the substantial trauma generally associated with invasive surgery. Treatment for Pathologies of the Hip Joint [0026] Unfortunately, minimally-invasive treatments for pathologies of the hip joint have lagged far behind minimally-invasive treatments for pathologies of the shoulder joint and the knee joint. This is generally due to (i) the constrained geometry of the hip joint itself, and (ii) the nature and location of the pathologies which must typically be addressed in the hip joint. [0027] More particularly, the hip joint is generally considered to be a “tight” joint, in the sense that there is relatively little room to maneuver within the confines of the joint itself. This is in marked contrast to the shoulder joint and the knee joint, which are generally considered to be relatively “spacious” joints (at least when compared to the hip joint). As a result, it is relatively difficult for surgeons to perform minimally-invasive procedures on the hip joint. [0028] Furthermore, the pathways for entering the interior of the hip joint (i.e., the natural pathways which exist between adjacent bones and/or delicate neurovascular structures) are generally much more constraining for the hip joint than for the shoulder joint or the knee joint. This limited access further complicates effectively performing minimally-invasive procedures on the hip joint. [0029] In addition to the foregoing, the nature and location of the pathologies of the hip joint also complicate performing minimally-invasive procedures on the hip joint. By way of example but not limitation, consider a typical detachment of the labrum in the hip joint. In this situation, instruments must generally be introduced into the joint space using an angle of approach which is offset from the angle at which the instrument addresses the tissue. This makes drilling into bone, for example, significantly more complicated than where the angle of approach is effectively aligned with the angle at which the instrument addresses the tissue, such as is frequently the case in the shoulder joint. Furthermore, the working space within the hip joint is typically extremely limited, further complicating repairs where the angle of approach is not aligned with the angle at which the instrument addresses the tissue. [0030] As a result of the foregoing, minimally-invasive hip joint procedures are still relatively difficult to perform and relatively uncommon in practice. Consequently, patients are typically forced to manage their hip pain for as long as possible, until a resurfacing procedure or a partial or total hip replacement procedure can no longer be avoided. These procedures are generally then performed as a highly-invasive, open procedure, with all of the disadvantages associated with highly-invasive, open procedures. [0031] As a result, there is, in general, a pressing need for improved methods and apparatus for treating pathologies of the hip joint. Current Approaches for Hip Joint Distraction [0032] During arthroscopic hip surgery, it is common to distract the hip joint so as to provide increased workspace within the joint. More particularly, during arthroscopic hip surgery, it is common to unseat the ball of the femur from the socket of the acetabular cup so as to provide (i) improved access to the interior of the joint, (ii) additional workspace within the interior of the joint, and (iii) increased visibility for the surgeon during the procedure. This hip joint distraction is normally accomplished in the same manner that the hip joint is distracted during a total hip replacement procedure, e.g., by gripping the lower end of the patient's leg near the ankle and then pulling the leg distally with substantial force so as to unseat the ball of the femur from the acetabular cup. [0033] However, since the distracting force is applied to the lower end of the patient's leg, this approach necessitates that the distracting force be applied across substantially the entire length of the leg. As a result, the intervening tissue (i.e., the tissue located between where the distracting force is applied and the ball of the femur) must bear the distracting load for the entire time that the hip joint is distracted. [0034] In practice, it has been found that the longer the distracting load is maintained on the leg, the greater the trauma imposed on the intervening tissue. Specifically, it has been found that temporary or even permanent neurological damage can occur if the leg is distracted for too long using conventional distraction techniques. [0035] As a result, the standard of care in the field is for the surgeon to limit the duration of distraction during arthroscopic hip surgery to 90 minutes or less in order to minimize damage to the intervening tissue due to joint distraction. In some situations, this can mean that desirable therapeutic procedures may be curtailed, or even eliminated entirely, in order to keep the duration of the distraction to 90 minutes or less. And even where the duration of the distraction is kept to 90 minutes or less, significant complications can nonetheless occur for many patients. [0036] In addition to the foregoing, in current hip distraction, it is common to use a perineal post to facilitate hip distraction. More particularly, and looking now at FIG. 16 , a perineal post is generally positioned between the legs of the patient so that the medial side of the femur which is to be distracted lies against the perineal post. After the patient's leg is pulled distally (i.e., in the direction of the pulling vector V P ), the leg is adducted so as to lever the leg against the perineal post, which moves the neck and ball of the femur in the direction of the lateral vector V L ; the combination of these two displacements is V D (i.e., the resultant vector of the vectors of V L and V P ). This ensures that the ball of the femur is unseated from the acetabular cup in the desired direction (i.e., in the direction of the resultant vector V D ). [0037] Unfortunately, it has been found that the use of a perineal post can contribute to the damage done to the intervening tissue when the leg is distracted too long. This is because the perineal post can press against the pudendal nerve and/or the sciatic nerve (as well as other anatomy) when distraction occurs. Thus, if the distraction is held too long, neurological damage can occur. This is another reason that the standard of care in the field is for the surgeon to limit the duration of distraction during arthroscopic hip surgery to 90 minutes or less. Additionally, the perineal post can exert pressure on the blood vessels in the leg, and it has been shown that blood flow in these vessels (e.g., the femoral vein, etc.) can be reduced, or in some cases completely occluded, while the hip is in distraction, thus placing the patient in danger of forming deep vein thrombosis or developing other complications. [0038] Additionally, current hip distraction limits the extent to which the leg can be manipulated under distraction during hip arthroscopy, since a substantial pulling force must be maintained on the distal end of the leg throughout the duration of the distraction. Due to this, and due to the fact that there are typically only 2-4 portals available for surgical access into the interior of the hip joint, visualization and access to hip joint pathology and anatomy is frequently hindered. This can limit the extent of surgical procedures available to the surgeon, and can prevent some procedures from being attempted altogether. Procedures such as mosaicplasty and autologous cartilage injection are examples of procedures which require access to extensive areas of the articular surfaces of the femoral head, but which are typically not performed arthroscopically because of the aforementioned access limitations due to leg distraction. [0039] Thus, there is a need for a new and improved approach for distracting the hip joint which addresses the foregoing problems. SUMMARY OF THE INVENTION [0040] These and other objects of the present invention are addressed by the provision and use of a new method and apparatus for distracting a joint. [0041] Among other things, the present invention provides a novel method for distracting a joint and for maintaining distraction of a joint, wherein the novel method minimizes damage to intervening tissue while maintaining distraction of the joint. In addition, the novel method allows visualization of areas in the hip joint that were not previously visible using a conventional hip distraction approach. [0042] The present invention also provides novel apparatus for distracting a joint and for maintaining distraction of a joint, wherein the novel apparatus comprises a novel joint-spacing balloon catheter for maintaining the distraction of a joint. In addition, the novel apparatus preferably includes a novel inflatable perineal post for use in distracting the joint. [0043] In one preferred form of the invention, there is provided a method for creating space in a joint, the method comprising: [0044] applying force to a body part so as to distract the joint and create an intrajoint space; [0045] inserting an expandable member into the intrajoint space while the expandable member is in a contracted condition; [0046] expanding the expandable member within the intrajoint space; and reducing the force applied to the body part so that the joint is supported on the expandable member. [0047] In another preferred form of the invention, there is provided a method for creating space in a joint, the method comprising: [0048] inserting a first expandable member into the interior of the joint while the expandable member is in a contracted condition; [0049] expanding the first expandable member within the joint so as to create a first intrajoint space; [0050] inserting a second expandable member into the first intrajoint space while the second expandable member is in a contracted condition; and [0051] expanding the second expandable member within the first intrajoint space so as to create a second intrajoint space. [0052] In another preferred form of the invention, there is provided a joint-spacing balloon catheter comprising: [0053] a shaft having a distal end and a proximal end; an expandable member attached to the distal end of the shaft, the expandable member being capable of supporting opposing bones of a previously-distracted joint when the distraction force is reduced; and a handle attached to the proximal end of the shaft. [0054] In another preferred form of the invention, there is provided a perineal post comprising a balloon. BRIEF DESCRIPTION OF THE DRAWINGS [0055] These and other objects and features of the present invention will be more fully disclosed or rendered obvious by the following detailed description of the preferred embodiments of the invention, which is to be considered together with the accompanying drawings wherein like numbers refer to like parts, and further wherein: [0056] FIGS. 1A-1D are schematic views showing various aspects of hip motion; [0057] FIG. 2 is a schematic view showing the bone structure in the region of the hip joints; [0058] FIG. 3 is a schematic anterior view of the femur; [0059] FIG. 4 is a schematic posterior view of the top end of the femur; [0060] FIG. 5 is a schematic view of the pelvis; [0061] FIGS. 6-12 are schematic views showing the bone and soft tissue structure of the hip joint; [0062] FIG. 13 is a schematic view showing cam-type femoroacetabular impingement (FAI); [0063] FIG. 14 is a schematic view showing pincer-type femoroacetabular impingement (FAI); [0064] FIG. 15 is a schematic view showing a labral tear; [0065] FIG. 16 is a schematic view showing how a perineal post is used to distract the hip joint in a conventional hip distraction; [0066] FIGS. 17-19 are schematic views showing a novel joint-spacing balloon catheter formed in accordance with the present invention; [0067] FIG. 20 is a schematic flowchart showing one novel aspect of a novel method for distracting a joint; [0068] FIG. 21 is a schematic view showing the novel joint-spacing balloon catheter of FIGS. 17-19 being deployed within a hip joint; [0069] FIG. 22 is a schematic flowchart showing another novel aspect of a novel method for distracting a joint; [0070] FIG. 23 is a schematic view showing how the leg of a patient may be manipulated once the ball of the femur is being supported on the inflated balloon of the joint-spacing balloon catheter, and once the external distracting force previously applied to the distal end of the leg has been released; [0071] FIGS. 23A-23D are schematic views showing an outer guiding member which may be used to deploy the joint-spacing balloon catheter within the joint; [0072] FIGS. 24-28 are schematic views showing how one or more expandable elements may be used to tether the joint-spacing balloon catheter to the capsule of the joint; [0073] FIG. 28A is a schematic view showing another means for stabilizing the joint-spacing balloon catheter within a joint; [0074] FIGS. 29 and 30 are schematic views showing how additional lumens may be provided in the elongated shaft of the joint-spacing balloon catheter in order to accommodate additional structures, e.g., guidewires, obturators, working instruments, optical fibers, etc.; [0075] FIGS. 31-35 are schematic views showing alternative configurations for the balloon of the joint-spacing balloon catheter; [0076] FIGS. 36-38 are schematic views showing additional alternative configurations for the balloon of the joint-spacing balloon catheter; [0077] FIGS. 39-52 are schematic views showing that the joint-spacing balloon catheter may comprise multiple balloons, with those multiple balloons being arranged in a variety of configurations; [0078] FIGS. 53-55 are schematic views showing how a balloon of the joint-spacing balloon catheter may comprise a plurality of separate chambers, with those chambers being arranged in a variety of configurations; [0079] FIGS. 56-60 and 60 A- 60 D are schematic views showing how a balloon of the joint-spacing balloon catheter may incorporate puncture protection within its structure; [0080] FIGS. 61-63 are schematic views showing how a associated structure may be used in conjunction with the joint-spacing balloon catheter so as to provide puncture protection for a balloon of the joint-spacing balloon catheter; [0081] FIGS. 64-72 are schematic views showing how a supplemental structure may be provided within a balloon of the joint-spacing balloon catheter so as to provide fail-safe support in the event that the balloon should lose its integrity; [0082] FIGS. 73-78 are schematic views showing additional mechanisms for expanding a balloon of the joint-spacing balloon catheter; [0083] FIGS. 79 and 80 are schematic views showing an inflatable perineal post provided in accordance with the present invention; and [0084] FIGS. 81 and 82 are schematic views showing another inflatable perineal post provided in accordance with the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Novel Joint-Spacing Balloon Catheter [0085] In one form of the present invention, there is provided a novel joint-spacing balloon catheter for use in distracting a joint, and particularly for maintaining the distraction of a joint, as will hereinafter be discussed in detail. [0086] More particularly, in this form of the invention, and looking next at FIGS. 17-19 , there is shown a novel joint-spacing balloon catheter 5 formed in accordance with the present invention. Novel joint-spacing balloon catheter 5 generally comprises an elongated shaft 10 having a balloon 15 disposed at its distal end and a handle 20 disposed at its proximal end. [0087] Elongated shaft 10 is preferably flexible, and preferably includes an internal stiffener 25 extending along at least a portion of its length so as to facilitate proper positioning of balloon 15 during use. Internal stiffener 25 could comprise a round or rectangular wire (e.g., such as shown in FIG. 19 ), and be made out of a metal (e.g., stainless steel, Nitinol, etc.) or plastic. If internal stiffener 25 comprises a rectangular wire, the short axis of the wire can provide flexibility (e.g., to enable the distal end of the joint-spacing balloon catheter 5 to navigate around the curvature of the femoral head); whereas, the long axis can provide stiffness to better control the position of the balloon in the joint space. If desired, elongated shaft 10 may also include a rigid overshaft 30 adjacent to handle 20 so as to further stiffen the proximal end of elongated shaft 10 , whereby to provide better control for the positioning of balloon 15 . Rigid overshaft 30 can be a stainless steel tube. Rigid overshaft 30 can be about 10 cm to about 30 cm in length, but is preferably about 12.5 cm to about 22.5 cm in length. A steering cable 35 is provided for steering the direction of balloon 15 . More particularly, steering cable 35 extends through elongated shaft 10 between the distal end of elongated shaft 10 and a steering control mechanism 40 provided on handle 20 . By manipulating steering control mechanism 40 , the user is able to steer the direction of balloon 15 , e.g., in the manner shown in FIG. 18 . More particularly, steering control mechanism 40 and steering cable 35 are adapted to cause shaft 10 to arc. This arc can be a radius of about 5 mm to about 10 cm, but is preferably a radius of about 1 cm to about 5 cm. [0088] Balloon 15 is preferably selectively inflatable/deflatable via an inflation/deflation lumen 45 extending through elongated shaft 10 and handle 20 . An inflation/deflation control mechanism 50 is interposed between inflation/deflation lumen 45 and a supply port 55 which is connected to an appropriate fluid reservoir (not shown). By manipulating inflation/deflation control mechanism 50 , the user is able to inflate/deflate balloon 15 as desired. Inflation/deflation control mechanism 50 may comprise a stopcock, a valve, a pump and/or other fluid control mechanisms. Balloon 15 preferably includes an atraumatic tip 60 at its distal end. [0089] On account of the foregoing, joint-spacing balloon catheter 5 may have its balloon 15 set to its deflated state via inflation/deflation control mechanism 50 , the deflated balloon may be advanced to a remote site using handle 20 and steering control mechanism 40 , and then balloon catheter 5 may have its balloon set to its inflated state by further manipulating inflation/deflation control mechanism 50 , whereby to support tissue and maintain the distraction of a joint, as will hereinafter be discussed in detail. Novel Method for Distracting a Joint [0090] In another form of the present invention, there is provided a novel method for distracting a joint, preferably the hip joint, and preferably using novel joint-spacing balloon catheter 5 . [0091] More particularly, in this form of the invention, and looking now at FIG. 20 , the hip joint is first distracted using a standard leg distraction technique, e.g., by positioning a perineal post between the patient's legs, pulling on the distal end of the leg with a substantial force, and then adducting the leg so as to unseat the ball of the femur from the acetabular cup, in the manner described above and shown in FIG. 16 . [0092] Next, joint-spacing balloon catheter 5 , with balloon 15 set in its deflated state, is inserted into the space created between the ball of the femur and the acetabular cup. This may be done under direct visualization (i.e., using an endoscope inserted into the distracted joint), or under fluoroscopy, or both. [0093] Then balloon 15 is inflated. See FIG. 21 . [0094] Next, the distal force which was previously applied to the distal end of the leg is partially or fully released. Release of the full distraction force has the beneficial effect of completely eliminating the tension load imposed on the intervening tissue, whereas a partial release of the distraction force only partially eliminates the tension load imposed on the intervening tissue—however, even such partial release of the distraction force can still meaningfully reduce the tension load imposed on the intervening tissue, and it provides a safeguard in the event that balloon 15 should prematurely deflate, e.g., mid-procedure. The aforementioned partial or full release of the external distraction force allows the ball of the femur to seat itself on the inflated balloon, with the balloon acting as a spacer so as to maintain a desired spacing between the ball of the femur and the acetabular cup. Thus, joint distraction is maintained even though a substantial distraction force is no longer being applied to the distal end of the leg. Since joint distraction can be reliably maintained without the risk of damage to the intervening tissue from a substantial externally-applied distraction force, the traditional concern to complete procedures in 90 minutes or less is substantially diminished, and complications from joint distraction are greatly reduced. This is a very significant improvement over the prior art. [0095] With the joint so distracted, the arthroscopic surgery can then proceed in the normal fashion. [0096] Significantly, and in accordance with another novel aspect of the invention (see FIG. 22 ), the use of joint-spacing balloon catheter 5 can enable the leg to be manipulated while the joint is in a distracted state. More particularly, it has been discovered that, once balloon 15 has been inflated within the joint and the pulling force applied to the distal end of the leg has been partially or fully released, so that the head of the femur is resting on the balloon, the leg can be moved about (i.e., pivoted) on the balloon. Manipulation can include flexion and extension, adduction and abduction, as well as internal and external rotation. See, for example, FIG. 23 . This manipulation of the leg while the joint is in a distracted, balloon-supported state enables more of the joint anatomy and pathology to be visualized and accessed, for superior surgical results. By contrast, a patient's leg cannot be manipulated in this manner when the leg is being distracted in a conventional manner, i.e., by a pulling force applied to the distal end of the leg. Therefore, procedures can be performed using the present invention which cannot be performed using conventional distraction techniques. This is a very significant improvement over the prior art. [0097] Additionally, some procedures which would normally require the creation of an additional portal to access pathology can be accomplished without the creation of the additional portal, thereby reducing the visible scar and potential morbidity of the additional portal. This is also a significant improvement over the prior art. [0098] At the conclusion of the arthoscopic surgery, a distal force is re-applied to the distal end of the leg so as to take the load off the inflated balloon, the balloon is deflated, and then the joint-spacing balloon catheter is removed from the interior of the joint. [0099] Finally, the distal force applied to the distal end of the leg is released, so as to allow the ball of the femur to re-seat itself in its normal position within the acetabular cup. [0100] With respect to the foregoing method of the present invention, it should be appreciated that joint-spacing balloon catheter 5 can be specifically located in the joint space so as to preferentially bias the position of the femoral head relative to the acetabulum when the pulling force on the distal end of the leg is relaxed and the ball of the femur transfers its load to (i.e., is seated on) the inflated balloon. For example, positioning joint-spacing balloon catheter 5 so that balloon 15 is more posterior in the joint causes the femoral head to settle in a more anterior position, which can improve visualization and access to the posterior acetabular rim. [0101] With respect to the foregoing method of the present invention, it should also be appreciated that joint-spacing balloon catheter 5 can be placed in the joint space so as to provide better visualization and access to the peripheral compartment of the hip. [0102] Thus it will be seen that the present invention provides a safe and simple way to significantly reduce trauma to intervening tissue in the leg when practicing leg distraction, since a substantial distally-directed force only needs to be applied to the distal end of the patient's leg long enough for the deflated balloon to be positioned in the distracted joint and for the balloon to thereafter be inflated—the distally-directed distraction force does not need to be maintained on the distal end of the patient's leg during the surgery itself. As a result, trauma to the intervening tissue is greatly reduced, and the surgeon no longer needs to limit the duration of distraction to 90 minutes or less in order to avoid damage to the intervening tissue. This is a very significant improvement over the prior art. [0103] In addition, the use of the present invention enables more of the joint anatomy and pathology to be visualized and accessed, since supporting the ball of the femur on an inflated balloon allows the initial external distraction to be relaxed, and allows the leg to be manipulated on the inflated balloon while the joint is in a distracted state. By contrast, the leg cannot be manipulated in this manner while the leg is being distracted in a conventional manner, i.e., by a pulling force applied to the distal end of the leg. Therefore, arthroscopic procedures can be performed using the present invention which cannot be performed using conventional distraction techniques. This is a very significant improvement over the prior art. [0104] Additionally, some procedures which would normally require the creation of an additional portal to access pathology can be accomplished without the creation of the additional portal, thereby reducing the visible scar and potential morbidity of the additional portal. This is also a significant improvement over the prior art. Further Details of the Joint-Spacing Balloon Catheter [0105] It will be appreciated that balloon 15 preferably serves as a both a spacer and as a pivot support to allow the manipulation of the femur while the joint is distracted. Balloon 15 is constructed so as to be atraumatic in order to avoid damaging the anatomy, including the cartilage surfaces of the joint. At the same time, and as will hereinafter be discussed in further detail, balloon 15 may be appropriately textured and/or sculpted in order to maintain its position within the joint, preferentially to either one of the acetabulum or femur, while still allowing the opposing bone to move smoothly over the balloon surface. [0106] In one preferred form of the invention, elongated shaft 10 has an outer diameter of about 0.040″ (or less) to about 0.250″ (or more). An outer diameter of approximately 0.120″ to 0.200″ is preferred for many hip applications. [0107] If desired, a retractable sheath (not shown) may be provided over shaft 10 in order to cover balloon 15 prior to inflation. [0108] And if desired, the distal end of shaft 10 can be pre-shaped with a bend so as to give joint-spacing balloon catheter 5 a directional bias at its distal end. [0109] Furthermore, if desired, and looking now at FIGS. 23A-23D , an outer guiding member 57 may be provided for directing joint-spacing balloon catheter 5 to a location within the joint. More particularly, in this form of the invention, outer guiding member 57 comprises a central lumen 58 sized to receive joint-spacing balloon catheter 5 ; the outer guiding member is advanced into position within the joint, and then joint-spacing balloon catheter 5 is advanced down the central lumen 58 of outer guiding member 57 so that the distal end of joint-spacing balloon catheter 5 is properly disposed within the interior of the joint. [0110] More particularly, FIG. 23A is a schematic view showing an outer guiding member 57 which may be used to deploy joint-spacing balloon catheter 5 within the joint. In many instances, the portal location does not directly align with the entrance of the joint space (i.e., with the acetabular rim region). Outer guiding member 57 has a curve at its distal end which can be aligned with the entrance of the joint space, thus facilitating the delivery of joint-spacing balloon catheter 5 into the interior of the joint space. The joint-spacing balloon catheter 5 is advanced through the central lumen 58 of outer guiding member 57 and exits in a direction which better facilitates navigating the distal end of the joint-spacing balloon catheter around the femoral head. The joint-spacing balloon catheter 5 could have a pre-shaped distal end that further enables guidance into the joint space. Alternatively, joint-spacing balloon catheter 5 could be steerable as discussed above. In practice, outer guiding member 57 is placed such that the distal tip of the outer guiding member is at or near the joint entrance ( FIGS. 23C and 23D ). Alternatively, the distal end of outer guiding member 57 can be placed within the joint space. The distal tip of outer guiding member 57 is oriented in the desired direction for proper placement of the balloon. Joint-spacing balloon catheter 5 is advanced through the central lumen 58 of outer guiding member 57 and into the joint space until balloon 15 is in the desired location (the arrows in FIGS. 23C and 23D indicate direction of balloon catheter delivery). The outer guiding member can be used to help adjust the final balloon position. The outer guiding member 57 can be left in place during the procedure to help tether the joint-spacing balloon catheter in position within the joint. Additionally, outer guiding member 57 can provide a conduit to remove the joint-spacing balloon catheter from the body. [0111] In one preferred form of the invention, balloon 15 is preferably approximately 28 mm in diameter, although it can also range from about 10 mm (or less) in diameter to about 50 mm (or more) in diameter if desired. Furthermore, the length of balloon 15 is preferably approximately 50 mm, although it can also range from about 10 mm (or less) in length to about 75 mm (or more) in length if desired. In this respect, it will be appreciated that balloons of various sizes may be used to address patients of different sizes, variations in anatomy, and/or different pathologies. [0112] Balloon 15 may be inflated with a pressure of up to about 1000 psi, and is preferably inflated with a pressure of up to about 200 psi, and is most preferably inflated with a pressure of up to about 100 psi. In this respect it will be appreciated that it is generally accepted that a force of about 50-80 lbs. is sufficient to distract the hip joint. In order for joint-spacing balloon catheter 5 to support this force, it must provide sufficient pressure over a sufficient surface area (force=pressure X area). Although there are a number of different balloon sizes and operating pressures which can be envisioned, there are limitations on the balloon size and pressure to consider. On the one hand, the balloon must be large enough to cover a sufficient amount of cartilage such that the pressure on the cartilage is lower than that which would damage the cartilage. On the other hand, the balloon must be small enough so as to permit access to and visualization of the operative areas. Hence, there is an optimal range of balloon size and operating pressure, and this optimal range is dependent on tissue dynamics. [0113] In one preferred form of the invention, balloon 15 is fabricated so as to be semi-compliant, although it can also be fabricated so as to be compliant or non-compliant if desired. Examples of semi-compliant balloon materials are polyurethane, nylon and polyether block amide (PEBA). An example of a compliant balloon material is silicone rubber. An example of a non-compliant balloon material is polyethylene terapthalate (PET). A compliant or semi-compliant balloon is generally preferred since it will deform under load to the shape of the surface which the balloon is contacting in order to help distribute load onto that surface. A semi-compliant balloon is generally most preferred since it will retain some aspects of its pre-load shape even when under load, which can be helpful in directing or maintaining bone positioning, particularly when the leg is being manipulated while in a distracted state. The thickness of the balloon material is preferably in the range of about 0.001″ to about 0.020″, and is most preferably between about 0.002″ and about 0.012″. The durometer of the balloon material is preferably in the range of about 30 Shore A to about 85 Shore D, and is most preferably between about 40 Shore D and about 85 Shore D. [0114] If desired, the surfaces of balloon 15 can be textured (e.g., with dimples, ridges, etc.) or covered with another material (e.g., a coating or covering) so as to prevent slippage of the balloon along cartilage when the balloon is being used to support a joint. At the same time, this surface texture or non-slip covering is configured so as to engage the cartilage without causing cartilage damage. In one preferred form of the invention, only a portion of the outer surface of the balloon is textured or covered with a non-slip material. For example, the portion of the balloon which faces the acetabulum could be textured or covered with a non-slip material, but the portion of the balloon which faces the femoral head could be non-textured or non-covered, so as to keep the surface facing the acetabulum from slipping while allowing the surface facing the femoral head to slide relative to the femoral head. In another preferred form of the invention, a majority of the balloon surface is textured or covered with a non-slip material. In yet another preferred form of the invention, two or more different textures or non-slip coverings are provided on the outer surface of the balloon, e.g., depending on the particular cartilage surface which they may engage. [0115] In yet another embodiment of the invention, the balloon is covered with a low friction material which enables slippage of the joint surface on the balloon. The low friction material may cover some or all of the balloon surface. [0116] The balloon may comprise both low slippage and low friction coverings if desired. [0117] Furthermore, if desired, fluoroscopic markings can be incorporated into or disposed on elongated shaft 10 , or incorporated into or disposed on balloon 15 , or incorporated into or disposed on another part of joint-spacing balloon catheter 5 , so as to render the apparatus visible under X-ray. Such fluoroscopic markings may comprise radiopaque ink applied to the apparatus, radiopaque bands applied to the apparatus, radiopaque material incorporated in the construction of the apparatus, and/or a radiopaque fluid used to inflate the balloon (such as a contrast agent). By way of example but not limitation, a radiopaque band material could comprise platinum. By way of further example but not limitation, a radiopaque fluid could comprise a contrast agent such as Dodecafluoropentane. [0118] In one preferred form of the invention, balloon 15 is preferably inflated with a liquid medium, e.g., saline; however, it could also be inflated with a gaseous medium, e.g., air. Among other things, the balloon can be inflated with a high viscosity fluid. This latter construction may be beneficial in the event of a balloon puncture as it would slow the pace of balloon deflation. If desired, a fluid could be used which changes viscosity when subject to changes in temperature, electrical charge, magnetic field, or other means. Alternatively, the balloon can be filled with a compound which increases in viscosity when exposed to saline. This latter construction can be advantageous in certain circumstances, e.g., during a balloon puncture, the escaping fluid would react to the saline present in the joint and could at least partially seal the puncture hole in the balloon. [0119] Where balloon 15 is inflated with a gaseous medium, and that gaseous medium is air, inflation/deflation control mechanism 50 may comprise a pump, and supply port 55 may be open to the atmosphere. [0120] In one aspect of the invention, and looking now at FIGS. 24-28 , joint-spacing balloon catheter 5 further comprises one or more expandable elements 60 in addition to balloon 15 . These expandable elements 60 can be another balloon, a collapsible braid, and/or some other structure which can expand when desired to a larger dimension. Expandable element 60 can be used to releasably secure joint-spacing balloon catheter 5 to the joint capsule. In one embodiment, and as shown in FIG. 24 , an expandable element 60 is located at the distal end of the joint-spacing balloon catheter. This expandable element 60 is expanded once the distal end of the balloon catheter (and the expandable element 60 ) has passed through the capsule 62 at the far side of the joint, so that the expandable element is deployed on the far side of the capsule, whereby to stabilize balloon 15 within the joint. See FIG. 25 . In another embodiment, a second expandable element 60 is expanded adjacent to the internal surface of the far capsule, as shown in FIG. 26 , so that the far side of the capsule is sandwiched between the two expandable elements 60 , whereby to further stabilize balloon 15 within the joint. In this respect it should be appreciated that the two expandable elements 60 may or may not be expanded simultaneously. In yet another embodiment, and looking now at FIG. 27 , one or more expandable elements 60 are disposed proximal to the balloon, to tether the joint-spacing balloon catheter to capsule 62 at the proximal portion of the joint, such as is shown in FIG. 28 . [0121] In another embodiment ( FIG. 28A ), a second cannula 63 is used to secure the distal end of joint-spacing balloon catheter 5 relative to the anatomy. More particularly, the distal tip of the joint-spacing balloon catheter, or a flexible element 64 which extends from the distal end of the joint-spacing balloon catheter (e.g., a guidewire), is passed into the tip of the second cannula 63 . The flexible element could be a wire, a suture, a ribbon, a catheter, a braid, or some other construction which is flexible or semi-flexible. The flexible element 64 can be received within the second cannula or, if desired, gripped within the second cannula. A gripping feature (not shown) could be provided in the second cannula to achieve this. Alternatively, the flexible element 64 could pass entirely through the second cannula. In any case, this construction results in the tip of joint-spacing balloon catheter 5 being stabilized in position by the second cannula 63 . [0122] Additionally, and looking now at FIG. 29 , another lumen 65 can be provided for a guidewire, obturator, light fiber, electrical wire, or the like, or as an additional inflation lumen, etc. And, as shown in FIG. 30 , further lumens 70 can be provided for working instruments, etc. If desired, a pre-shaped guidewire or obturator can be placed through one of the lumens of elongated shaft 10 in order to bias the tip direction of the joint-spacing balloon catheter 5 as the joint-spacing balloon catheter is advanced over the pre-shaped guidewire or obturator. Alternatively, a second steerable wire can be placed through one of the lumens, so as to enable steering of the balloon catheter in a second direction. [0123] To improve resistance to kinking, or to provide the shaft with the desired stiffness and torsional characteristics, a braid or coil 71 ( FIG. 30 ) could be incorporated into the catheter. The braid or coil could comprise a stainless steel wire, a Nitinol wire, etc. Braid or coil 71 could be incorporated at any section of joint-spacing balloon catheter 5 , but is preferably located in at least the flexible section of the catheter. [0124] In FIGS. 17-19 , balloon 15 is shown with a generally cylindrical configuration. However, if desired, balloon 15 can have different configurations. Thus, for example, and looking now at FIGS. 31 and 32 , balloon 15 can comprise a pair of opposing flat surfaces 72 ; or, and looking now at FIGS. 33 and 34 , balloon 15 can have an hourglass shape which includes an intermediate section 73 of reduced diameter; or, and looking now at FIG. 35 , balloon 15 can have a generally hourglass shape with a pair of opposing flat surfaces 72 . The aforementioned hourglass shapes, although depicted symmetrical, can also be asymmetric. For example, one end of the hourglass-shaped balloon may be of a larger dimension (length, diameter, etc.) than the other end of the hourglass-shaped balloon. [0125] Balloon 15 may also be in the form of an arc or other curvature (i.e., a geometry where one side has a greater curvature than the other side), or some other shape (e.g., U-shaped), so as to fit around the ligamentum teres. See FIG. 36 . Additionally, balloon 15 could have the shape of a torus, so as to provide a seat for the ball of the femur. See FIGS. 37 and 38 . [0126] It is also possible to provide joint-spacing balloon catheter 5 with more than one balloon 15 . Where more than one balloon is provided, the balloons can be disposed in series (i.e., end-to-end, such as is shown in FIG. 39 ), or in parallel (such as shown in FIGS. 40 and 41 ), with or without complementary geometries (such as shown in FIGS. 42 and 43 ), or combinations of such geometries (such as shown in FIG. 44 ), or toroidal (such as is shown in FIG. 45 ), etc. The shafts of the multiple balloons may be separated at their distal end (such as is shown in FIG. 40 ) or may be joined at their distal ends (such as is shown in FIG. 41 ). Multiple balloons may be of the same construction, or they may be of different constructions. For example, multiple balloons may be of different sizes, shapes, materials, compliances, coatings, surface textures, coverings, colors, and/or other aspects of construction. Additionally, the multiple balloons may be inflated to different pressures and/or volumes. [0127] These multiple balloons 15 can also be disposed in a mutually-supporting configuration, as shown in FIGS. 46-52 . By arranging the multiple balloons 15 in a mutually-supporting configuration, the multiple balloons 15 may better conform to the acetabulum and femoral surfaces, which would be beneficial in order to reduce pressure on the cartilage and/or to help maintain the balloons in position within the joint space (i.e., to prevent slipping). In this form of the invention, a balloon catheter 5 could have an assembly of balloons 15 that would collectively act as a compliant or semi-compliant device even though the individual balloons are non-compliant, or vice versa. An additional benefit of arranging the multiple balloons 15 in a mutually-supporting configuration is that if one of the balloons deflates, the other balloons can still maintain a substantial portion of the joint space. In one preferred construction, the balloons 15 can slide against each other to spread out, e.g., to spread out in a lateral direction. Where joint-spacing balloon catheter 5 comprises multiple balloons 15 , preferably, a separate inflation/deflation lumen is provided for each balloon, so that each balloon can be separately inflated or deflated, although a single inflation/deflation lumen could be used to simultaneously inflate/deflate more than one balloon. By permitting each balloon of a group of balloons to be selectively inflated, the surgeon can influence the manner in which the ball of the femur is supported relative to the acetabular cup. In one preferred manner of use, each of the balloons may be inflated to a different volume (and/or pressure) than others of the balloons. This approach can be used to impart a specific shape to the overall balloon structure. Also, some of the balloons 15 can be made compliant, and others non-compliant, so as to achieve a desired pressure distribution and/or shape for the overall balloon structure. [0128] It is also possible to provide each of the balloons 15 with a plurality of separate internal chambers 75 ( FIGS. 53-55 ). Preferably each of these separate chambers 75 can be selectively inflated so as to influence the manner in which the ball of the femur is supported relative to the acetabular cup. Thus, in this sort of construction, selective inflation of the various chambers can be used to adjust the position of the ball of the femur within the acetabular cup when the pulling force on the distal end of the leg is relaxed. The use of multiple chambers may also provide a safer design. More particularly, in the event that one of the chambers 75 is punctured during a procedure, the use of multiple chambers 75 may permit some joint distraction to be maintained, thus reducing the chances that, for example, an instrument will be wedged between the femoral head and acetabulum. [0129] If desired, balloons 15 can be formed so as to be puncture resistant in order to minimize the possibility of inadvertently deflating the balloon, e.g., with an errant surgical instrument. To this end, and looking now at FIG. 56-59 , a balloon 15 can embed, or sandwich, a puncture-resistant structure 80 (e.g., a coil or mesh or strand or braid formed out of Nitinol, or stainless steel, or a polymer, etc.) between two layers of material (preferably a non-abrasive elastomer). Alternatively, the puncture-resistant structure 80 could be placed on one side of, or embedded within, a single sheet of material, such as is shown in FIG. 60 . This puncture-resistant structure 80 may be a separate element added to the wall of the balloon or a coating applied to the wall of the balloon. The puncture-resistant structure 80 may also be a layer of material within the side wall of the balloon; for example, the outer layer may be a puncture-resilient material (such as polyurethane) to enhance puncture resistance, while the inner layer material maintains the balloon pressure (such as PET). In one preferred construction, puncture-resistant structure 80 covers a substantial portion of the balloon surface. In another preferred construction, the puncture-resistant structure 80 covers a smaller portion of the balloon surface; in this instance, the surface incorporating the puncture-resistant structure 80 is disposed on the side of the balloon where instruments are used (which could puncture the balloon). [0130] Furthermore, if desired, and looking now at FIGS. 60A-60D , the distal end of joint-spacing balloon catheter 5 could include a shroud 82 disposed over balloon 15 . Shroud 82 may be formed out of a puncture-resistant material so as to protect balloon 15 from inadvertent puncture. Additionally, and/or alternatively, shroud 82 could be formed so as to define the volume created within the joint when balloon 15 is inflated. This construction can be advantageous where balloon 15 is formed out of a compliant material and it is desired to control the manner in which space is created within the joint, i.e., by using a non-compliant or semi-compliant shroud 82 . Additionally, and/or alternatively, shroud 82 could be formed out of a material which provides slippage (e.g., it can be formed out of ePTFE). This can be beneficial in a number of ways. First, it can facilitate easier delivery of the balloon into the joint, including passage through the entry cannula. In a similar way, shroud 82 can also facilitate easier removal of the joint-spacing balloon catheter from the joint, including through the entry cannula. By having enhanced slippage properties, shroud 82 can also facilitate joint manipulation on the balloon. The shroud's geometry (e.g., tapered ends) can also facilitate ease of delivering and removing the joint-spacing balloon catheter to and from the joint space; this may be particularly beneficial if the balloon catheter goes through an entry cannula. Alternatively, the shroud 82 could be formed out of a material which prevents slippage on the joint surface (e.g. a low durometer elastomer). This can be beneficial to enable the balloon to remain stationary on the joint surfaces once it has been placed in the joint space. Additionally, and/or alternatively, shroud 82 can be constructed so as to provide better endoscopic visualization of the balloon; for example, shroud 82 can be an opaque color. [0131] Alternatively, and looking now at FIGS. 61-63 , a shield 85 could be placed alongside balloon 15 to protect the balloon from being punctured from that direction. Shield 85 is preferably introduced into the joint after the balloon has been inserted and inflated, but shield 85 could also be inserted into the joint prior to that if desired. Shield 85 could be made out of a material similar to the puncture-resistant structure 80 described above. [0132] Alternatively, and looking now at FIGS. 64-68 , a balloon-within-a-balloon configuration can be used to provide one or more secondary “fail-safe” (or “safety”) balloons 90 within the primary balloon 15 —such a construction can minimize the risk that joint distraction will be lost in the event that the primary balloon 15 is inadvertently deflated, e.g., by an accidental puncture. If desired, the inner balloon 90 can be made of a different material than the outer balloon 15 . In one preferred construction, inner balloon 90 is non-compliant and outer balloon 15 is semi-compliant. The inner and outer balloons could also have different wall thicknesses, geometries, or other aspects of construction as discussed above. [0133] Alternatively, a different type of secondary structure can be deployed in balloon 15 in order to prevent balloon 15 from completely collapsing in the event that it is punctured. In one embodiment, and looking now at FIG. 69 , a wire 95 is delivered into the interior of the balloon and fills up a portion of the internal balloon volume; in the event that the balloon is punctured, wire 95 provides support to prevent the joint space from collapsing. Wire 95 is preferably made of Nitinol, but could also be formed out of another metal or polymer if desired. In another embodiment, and looking now at FIG. 70 , a wire 100 is delivered across the length of the balloon and set in a bowed configuration. The bowed wire 100 provides mechanical support in the event the balloon is punctured. In FIG. 71 , an exemplary mechanical scaffold 105 is shown deployed in the interior of the balloon so as to provide a safety mechanical support. In FIG. 72 , an expandable foam 110 is deployed within the interior of the balloon; foam 110 expands to fill some or most of the internal balloon space. In one embodiment, expandable foam 110 absorbs fluid and will therefore absorb saline within the balloon. This construction can reduce the speed at which a punctured balloon will deflate. [0134] In yet another embodiment ( FIGS. 73 and 74 ), the balloon is filled with beads 115 . Beads 115 could be absorbent polymer or foam, or non-absorbent. As shown in FIGS. 75-77 , if beads 115 are non-absorbent, the balloon's inflation fluid can be evacuated from the balloon after beads 115 have been introduced into the inflated balloon, leaving a compact “bean bag” structure to maintain the joint space. As shown in FIG. 78 , beads 115 are preferably delivered into the interior of the balloon in a strand configuration, i.e., mounted on a filament 116 . This approach has the additional advantage that, in the event that the balloon should lose its integrity, beads 115 can be safely removed without leaving any beads in the hip joint, i.e., by pulling proximally on filament 116 . If desired, beads 115 can be disposed between a primary outer balloon 15 and secondary inner balloon 90 . [0135] If desired, joint-spacing balloon catheter 5 can include pressure regulation, e.g., a release valve (not shown) to ensure that a balloon is not inflated beyond a maximum level, or an alarm or other alert (not shown) to advise the user that a balloon has been inflated beyond a pre-determined level. This can be important to avoid damage to the patient's tissue or to reduce the risk of inadvertent balloon rupture. [0136] Furthermore, a check valve (not shown) may be installed on the inflation port(s) 55 to enable joint-spacing balloon catheter 15 to be disconnected from the fluid reservoir while maintaining pressure in balloon 15 . [0137] It is also possible to place markings (e.g., longitudinal lines) along the body of balloon 15 , or to color the balloon material, so as to improve endoscopic visualization of the balloon, including to show the degree of balloon inflation. Alternatively, the fluid used to inflate the balloon could be colored, or the balloon surface could have texture, in order to aid visualization of the balloon. Alternatively, a transparent, thick-walled balloon 15 can be used to increase visualization of the balloon by increasing the refraction of light, which will make the balloon foggy in appearance. Alternatively, a coating could be applied to the balloon material which improves the endoscopic visualization of the balloon. Alternatively, a second balloon or an expandable extrusion could be placed over the primary balloon so as to improve endoscopic visualization. The second balloon and/or expandable extrusion may be colored for improving endoscopic visualization. This configuration can also add to the puncture resistance of the primary balloon and assist in the delivery and retrieval of the primary balloon. [0138] The joint-spacing balloon catheter 5 may also comprise a sensor (not shown). The sensor can measure the temperature of the surrounding tissue or fluid in the joint (e.g., the sensor may be a temperature sensor). The sensor may also detect characteristics of the adjacent cartilage, such as thickness, density, and/or quality (e.g., the sensor may be an ultrasound device, etc.). The sensor could be located on shaft 10 or on balloon 15 , or on another portion of joint-spacing balloon catheter 5 . External Distraction of the Limb [0139] In the foregoing description, the external distraction of the limb is generally discussed in the context of applying a distally-directed distraction force to the distal end of the leg. However, it should be appreciated that the distally-directed distraction force may be applied to another portion of the leg, e.g., to an intermediate portion of the leg, such as at or about the knee. Thus, as used herein, the term “distal end of the leg” is meant to include substantially any portion of the leg which is distal to the ball of the femur, such that by applying the external distraction force to the leg, a tension load is imposed on the intervening tissue. Furthermore, as used herein, the term “intervening tissue” is intended to mean the tissue which is interposed between the location where the external distraction force is applied to the leg and the ball of the femur. Inflatable Perineal Post [0140] The present invention also preferably comprises the provision and use of a novel inflatable perineal post for facilitating joint distraction. [0141] More particularly, and looking now at FIGS. 79 and 80 , there is shown an inflatable perineal post 120 which generally comprises a relatively narrow, substantially rigid inner core 125 surrounded by a relatively wide, substantially soft inflatable balloon 130 . In an alternative embodiment as is shown in FIGS. 81 and 82 , inflatable perineal post 120 comprises a soft inflatable balloon 130 is supported on one or more sides by a substantially rigid support structure 135 . Such a non-cylindrical construction, with inflation being directed along selected directions, can be highly beneficial, since it can reduce engagement of the non-working portions of the perineal post with patient anatomy (e.g., the genitalia). Still other post shapes and configurations can be envisioned by one skilled in the art in view of the present disclosure. [0142] The inflatable balloon 130 of the inflatable perineal post 120 is preferably constructed out of a semi-compliant material, but it could also be compliant or non-compliant. The inflatable balloon 130 of the inflatable perineal post 120 may involve a covering (not shown) for contact with the patient; this covering may be a non-slip material. The inflatable balloon 130 is preferably inflated with a manual or electric pump. The inflatable perineal post 120 could include a read-out panel displaying the balloon pressure. [0143] The inflatable perineal post 120 may also comprise physiologic sensors (not shown) for monitoring parameters such as patient skin temperature and blood flow. Such parameters may be reflective of patient conditions of interest to the surgeon, e.g., a falling patient skin temperature is frequently indicative of reduced blood flow. These physiologic sensors could be incorporated into the surface of the balloon, or they could be separate sensors which are included as part of a kit provided with the inflatable perineal post. The physiologic sensors are adapted to be connected to a monitor so as to provide read-outs on the monitor. [0144] In use, the deflated perineal post balloon is positioned between the patient's legs, the joint is distracted by pulling on the distal end of the leg so that the ball of the femur is spaced from the acetabular cup, the perineal post balloon is inflated, a joint-spacing balloon catheter 5 is inserted into the distracted joint, the balloon 15 is inflated, the force applied to the distal end of the leg is relaxed so that the ball of the femur settles back down onto the one or more inflated balloons 15 , and then the perineal post balloon 130 is at least partially deflated. At this point the arthroscopic surgery can be conducted without trauma to the patient's tissue, due to either the distal distraction of the leg or due to engagement of the perineal post with the tissue of the patient. At the conclusion of the surgery, the distal end of the leg is pulled distally again, the perineal post balloon 130 is inflated, the joint-spacing balloon 15 is deflated, the joint-spacing balloon catheter 5 is removed from the joint, and the joint is reduced. Alternatively, the perineal post balloon could be inflated prior to pulling on the distal end of the leg. Or, alternatively, the perineal post balloon 130 could be deflated prior to withdrawal of the force being applied to the distal end of the leg. In some cases, only one of either (i) pulling on the leg, or (ii) inflating of the perineal post is performed in order to remove or re-position the joint-spacing balloon. [0145] If desired the inflatable perineal post 120 may be used to replace a standard perineal post, and is used in conjunction with a standard traction table; in other words, in this form of the invention, the inflatable perineal post 120 is not used in conjunction with a joint-spacing balloon catheter 5 . One Preferred Form of the Invention [0146] In one preferred form of the present invention, the aforementioned novel method for distracting the joint is implemented using the aforementioned novel joint-spacing balloon catheter 5 and the aforementioned inflatable perineal post 120 . [0147] More particularly, in this form of the invention, the hip joint is first distracted by pulling on the distal end of the leg just above the ankle, and then inflating the inflatable perineal post, where the perineal post is positioned between the patient's legs. The leg may be adducted so as to lever the femur laterally. Alternatively, the inflatable perineal post could be inflated prior to the distal end of the leg being pulled distally. [0148] Next, the surgeon identifies a portal location for joint-spacing balloon catheter delivery. Then a needle is placed into the joint, the stylet is removed, a guidewire is delivered through the needle, and then the needle is removed. The guidewire can be placed in the desired delivery path of the joint-spacing balloon catheter 5 . [0149] An arthroscopic cannula or outer guiding member may then be emplaced if desired; in this instance, the guidewire may be removed if desired. [0150] Next, a joint-spacing balloon catheter 5 of the appropriate size is selected from a kit providing a range of differently-sized joint-spacing balloon catheters. Then the joint-spacing balloon catheter 5 is delivered over the guidewire (either percutaneously or through a cannula) to the target site between the femoral head and the acetabulum. The joint-spacing balloon catheter 5 may be rotated as appropriate if there is asymmetry in the balloon's shape. Alternatively, the joint-spacing balloon catheter 5 may be delivered through a cannula without the use of a guidewire. [0151] Next, a syringe (or other inflation device) is secured to the joint-spacing balloon catheter 5 , and the balloon 15 is inflated to the desired pressure and/or size. If there is more than one balloon 15 , the additional balloon(s) can be inflated. If the additional balloon(s) are used to affect the direction of joint spacing, the pressure and/or size of each balloon is adjusted so as to achieve the desired joint spacing direction. [0152] Once the balloon has been inflated to the desired pressure and/or size, the distraction force applied to the leg is at least partially removed, allowing the head of the femur to rest on the inflated balloon (which is itself supported by the acetabulum). [0153] Additionally, the inflatable perineal post 120 is deflated as appropriate; this could occur before the leg distraction force is released. [0154] The balloon 15 can be re-positioned by re-applying distraction force to the leg and/or re-inflating the inflatable perineal post 120 , deflating balloon 15 and re-positioning the joint-spacing balloon catheter 5 , re-inflating the balloon of the joint-spacing balloon catheter, then releasing the leg distraction and/or deflating the inflatable perineal post. The balloon 15 may be placed in a location which directs the distraction in a preferred direction. Alternatively, where the joint-spacing balloon catheter comprises a plurality of balloons, the balloons may be inflated to different sizes and/or pressures in order to direct the joint distraction in a preferred direction. [0155] With the balloon maintaining the joint distraction, the leg may be manipulated (i.e. rotated, flexed, etc.) in order to visualize and access pathology through the established portals. [0156] Then the arthroscopic surgery is conducted. The leg may be manipulated a number of times through the procedure in order to visualize, access and treat pathology. [0157] At the conclusion of the arthroscopic surgery, the hip joint is distracted again, e.g., by pulling on the distal end of the leg just above the ankle, so as to lift the head of the femur off the balloon. The perineal post balloon may be inflated. The balloon 15 of the joint-spacing balloon catheter is deflated and the joint-spacing balloon catheter is removed. [0158] Thereafter, the distraction force applied to the leg may be removed, allowing the head of the femur to settle back on the acetabulum. [0159] In another form of the invention, while the distal end of the leg is held stationary, the perineal post 120 is inflated to break the suction seal of the hip joint and enable the joint-spacing balloon catheter 5 to be placed in the joint and inflated. In this case, no pulling on the leg is performed. This would have the benefit of eliminating a piece of equipment from the surgery and reducing the corresponding surgical time associated with using that equipment. [0160] In yet another form of the invention, the joint-spacing balloon catheter 5 can perform some or all of the joint distraction. In one embodiment, a first joint-spacing balloon catheter 5 is placed adjacent to the femoral head and the balloon is inflated. The leg is then manipulated in abduction or adduction (depending on balloon location), thus levering the femoral neck against the balloon. This levering creates a gap at the acetabular rim. A second joint-spacing balloon catheter 5 is then inserted into the gap and delivered into the joint space (the space between the femoral head and the acetabulum). The balloon of the second joint-spacing balloon catheter is then inflated and distracts the joint; that is, opens up the joint space. In one embodiment, the first balloon is placed on the lateral/superior aspect of the femoral neck. Once the second balloon is inflated, the first balloon can be deflated and withdrawn. The first balloon may be of a different size and shape as the second balloon. It also may be inflated to a different pressure. Kits [0161] The joint-spacing balloon catheter 5 and the inflatable perineal post 120 may be offered as part of a single kit. A guidewire or obturator, outer guiding member and a balloon inflation device may additionally be provided. Use of the Present Invention for Other Applications [0162] It should be appreciated that the present invention may be used for distracting the hip joint in an open, more invasive procedure. The present invention can also be used in hip joint pathologies where joint distraction is not needed but space creation is needed, e.g., to visualize and/or to address pathologies in the peripheral compartment or pathologies in the peritrochanteric space. Additionally, the present invention may be used for distracting joints other than the hip joint (e.g., it may be used to distract the shoulder joint). Modifications of the Preferred Embodiments [0163] It should be understood that many additional changes in the details, materials, steps and arrangements of parts, which have been herein described and illustrated in order to explain the nature of the present invention, may be made by those skilled in the art while still remaining within the principles and scope of the invention.

A method for creating space in a joint, the method comprising: applying force to a body part so as to distract the joint and create an intrajoint space; inserting an expandable member into the intrajoint space while the expandable member is in a contracted condition; expanding the expandable member within the intrajoint space; and reducing the force applied to the body part so that the joint is supported on the expandable member.

TECHNICAL FIELD [0001] The invention is about encrypted communication and its protocol. A specific emphasis is placed on the backward security and recovery properties of the protocol. It is assumed that an adversary can now and then expose all of the cryptographical security data i.e. private keys and other data stored on participants' computers. The presented method tries to make the damages of security data exposure as small as possible. Practical example where the protocol can be used is encrypted email. BACKGROUND ART [0002] We address the problem of encrypted communication over insecure networks using computers whose contents can occasionally be studied by an adversary. Insecurity of the network means that it must be assumed that not necessarily every encrypted message reaches the intended receiver. The messages may be received at different order than they were sent. It is also expected that an adversary can now and then expose all of the cryptographical security data i.e. private keys and other data stored on participants' computers. The adversary then uses this exposed snapshot of security data (called shortly snapshot) to obtain as many previous or future plaintexts as possible. The presented method tries to make the damages of the security data exposure as small as possible. [0003] Practical example is encrypted email communication. Even if every message would reach its destination the user may process only some of them and those in an ad hoc order. The user should be able to enjoy the backward security concept: An exposure of current security data should not compromise previously decrypted data. Clearly also the recovery i.e. the regaining of the state where the adversary cannot decrypt messages created after the snapshot would be a great advantage. It must be assumed that the user has no knowledge of the attackers success. [0004] The usage of backward security was mentioned by Ross Anderson in an invited lecture in Fourth Annual Conference on Computer and Communications Security. ACM, 1997. Summary appears in: Two remarks on public key cryptology http://www.cl.cam.ac.uk/users/rja14/, 2001. Also the idea of protecting future communication after the exposure is discussed in the paper. According to Anderson in traditional (symmetric) systems, the backward security is provided by key updating: “two or more principals who share a key pass it through a one-way hash function at agreed times: K i =h(K i−1 ).” Because of the one-way function the previous key cannot be derived from the current key. [0005] The future keys however can de derived by the attacker. To protect them “two or more principals who share a key hash it at agreed times with the messages they have exchanged since the last key change: K i+1 =h(K i ,M i1 ,M i2 , . . . )”. Backward security is still provided and also protection of future messages if the attacker misses one previous message. As noted by Anderson the advent of public key cryptography and Diffie-Hellman (DH) key exchange offers a stronger form of protection: when fresh public DH keys have been exchanged the security has been regained even if all the previous traffic is decrypted by the opponent. In this invention the idea that some kind of representation of previous keys affects new ones is used together with the possibilities that the DH key exchange offers. [0006] This recovery or freshness feature of the DH key exchange between two parties is widely used in the handshake phase of interactive session protocols. During the initial handshake the DH key exchange is performed and the shared secret is used as a security parameter for later message exchange. The individual messages during the session are then encrypted/decrypted on the basis of these parameters without any further DH exchange. If an attacker obtains the private key of one of the DH parties the whole session is exposed. This invention can also be seen as an approach to improve the security after the initial handshake. Please note that the communication need not necessarily be an online one. The presented protocol can naturally be used even if there are days between message movements—an example being email communication. Essential is that in the beginning the two communication parties are introduced to themselves via the protocol initialization. [0007] The current literature that deals with the problem of backward security in digital signatures and in encryption uses public keys in their more traditional meaning: one public key is distributed to many persons, which can then use it to send encrypted messages to the creator of the public key. The backward security methods in current literature are developed for this more general case. In this invention however the public keys used are intended to be used only between two specific and fixed communication parties—the fixed sender and the fixed receiver. In this sense our keys could be called session keys between two parties. In our method when two persons send a message to the same receiver both senders use different public keys of the receiver. The senders have no knowledge of the public key the other sender uses. The more general case where only one public key is reserved for many senders leads to more complex solutions. Please note that the current literature also uses the term forward-security in the same sense we use the term backward security: a current exposure does not expose old decrypted communication. The first method for the general case is R. Canetti, S. Halevi, J. Katz: A Forward-Secure Public-Key Encryption Scheme. EUROCRYPT 2003, LNCS 2656, 255-271. Springer-Verlag, 2003. Their method does not provide recovery. The recovery is added by Y. Dodis, M. Franklin, J. Katz, A. Miyaji, M. Yung: Intrusion-Resilient Public-Key Encryption. Topics in Cryptology-CT-RSA 03, Lecture Notes in Computer Science Vol. 2612, M. Joye ed, Springer-Verlag, 2003. This approach uses special update and refresh messages. [0008] If the presented protocol is used in e.g. email communication each new contact must be processed through the protocol initialization phase. If the methods based on the more general usage of public keys are used this need not be done—however a public key must have somehow been delivered to the sender of the first message. Our initialization requires that both parties send one initialization message. Our protocol provides backward security and recovers when messages are exchanged. [0009] In symmetric encryption setting the problem of protecting old traffic is studied by M. Bellare, B. Yee: Forward-Security in Private-Key Cryptography. Extended abstract in Topics in Cryptology-CT-RSA 03, Lecture Notes in Computer Science Vol. 2612, M. Joye ed, Springer-Verlag, 2003. They recommend the usage of forward-secure pseudorandom bit generators to be used as a central primitive. This is our approach too. Their construction is such that the generator's input is a previous state (seed) and it generates a new state and the required random output bits. The old state is destroyed. If from the generated output bits it is infeasible to derive the previous state (seed) used, then the construction protects old outputs. To this construction we add another input: a Diffie-Hellman shared secret. This is added to provide the recovery feature. Our state is maintained in both computers and these states are required to go through same values during the communication. [0010] By pseudorandomness it is understood to mean that it is infeasible to derive the initial seed from the outputted bits or another outputted bit from another ones and that if the seed is unknown the outputted bits are unpredictable. One construction that can be used is based upon the Goldreich-Levin hard-core bit and Blum-Micali iteration, see O. Goldreich, L. Levin: A Hard Core Predicate for any One Way Function. Proceedings, 21st ACM STOC, 1989, 25-32. and M. Blum, S. Micali: How to Generate Cryptographically Strong Sequences of Pseudo-random Bits. SIAM Journal of Computing, 13. no 4, 1986, 850-864. Another PRG providing similar properties i.e. pseudorandom bits can be used instead of this generator. [0011] Let's now look the usage of DH exchange more closely. In traditional DH key exchange both parties send one message before the shared secret is computed and the actual encryption of the plaintext can be done. To provide optimal backward security and recovery one could do the DH exchange always before a plaintext should be encrypted. However, now only one third of the messages would carry information. Assume now that the attacker obtains one of the private keys. Then he could decrypt one cryptotext based on the obtained private key. [0012] If the messaging would always happen in turns—every message is replied—the DH exchange could be done so that every message carries one new public key for immediate DH calculation to decrypt the encrypted text in the message and one another new public key for the next message to be received. Every private key would be destroyed after the DH calculation. Every message would carry information and again the attacker could only read one message based on one obtained private key. [0013] Problems will arise if a participant is allowed to send many messages before receiving a new public key. The sender of many consecutive messages must use the most recently received public key for all the messages he sends. If the attacker obtains the corresponding private key the backward recovery will be lost, the attacker can read all messages decryptable by this private key even if he obtains the key just before the last such message is decrypted. [0014] One development further would be to include a fixed number of new public keys in every message; the sender would prefer to use a public key only once. Suppose now that a sender will never use more messages than this fixed number before receiving a new set of public keys. Consider now the properties of such a system. There would be backward security and protocol would recover when the sender has received a new set of public keys. The presented invention will have backward security and recover at same time like this obvious fixed case but it uses only 3 new public keys in every message without a limit on the number of consecutive messages sent. One of the 3 keys is used for immediate DH calculation and two other ones are delivered to the message's receiver to be used in his next sendings. SUMMARY OF INVENTION [0015] The presented protocol uses public key encryption and utilizes 3 new public keys in every message. These keys are randomly (pseudorandomly) generated i.e. randomness is collected from some source and pseudorandom generator produces the private keys, then the seed is destroyed. One of the public keys is used for immediate DH computation—two keys are reserved for future DH computations. New to the current state of the art is that a message may contain history information: a list of recently used DH public keys and identifiers of their DH counterparts. Also stored old data called state is used together with a pseudorandom bit genrator (PRG) when generating a new state and symmetric key—a symmetric key is produced not only by a result of DH shared secret computation, but also with the help of this old data. A block cipher uses the produced symmetric key to encrypt or decrypt one message. [0016] The used PRG must have following properties: the bits produced must be pseudorandom and unpredictable i.e. from the result it must be infeasible to derive the seed or another outputted bit from another ones, also if the seed is unknown it must be infeasible to derive the outputted bits. We arrange things so that the initial seed x 0 will be unknown to the attacker if he either misses a state or a DH shared secret—the seed x 0 is set to be the xor'd value of both of them. [0017] One PRG that can be used is described next. Now let f be a one-way permutation and r a random binary vector, x 0 is the initial seed, b(r,x) is a function that computes the Goldreich-Levin hard-core bit from x. Due to the Blum-Micali theorem of iterating a one-way permutation and Goldreich-Levin hard-core bit the n bits b(r,x 0 ), b(r,f(x 0 )), b(r,f(f(x 0 ))) . . . b(r,f n−1 (x 0 )) are pseudorandom and unpredictable if x 0 is unknown, the random vector r need not be unknown. The random vector r is chosen to be the DH shared secret. This PRG has the required properties. In this construction the required one-way permutation can be emulated by a block cipher's encryption operation, see the detailed description section. [0018] Now if the adversary wants to proceed forward but cannot produce x 0 he cannot produce the outputted bits. If the adversary wants to go backwards and has obtained the outputted bits and the DH shared secret he still cannot determine x 0 . Neither can other outputted bits be derived from each other if some of them are revealed to the adversary. [0019] The history information in messages is needed because it enables the states being produced in forward proceeding order even if messages are not decrypted in order. In such a case the history data: a list of recently used DH public keys and identifiers of their DH counterparts—is read and used to produce the states and keys in order. A produced key is stored together with its message number. When a message corresponding to this number should be decrypted the key is fetched from the store and then removed. Only the minimum amount of history information needed is included in a message. When a message is decrypted the history data to be placed in the next outgoing message can be decided. The history data although consisting of public keys is encrypted—this is done to prevent a casual observer from doing any conclusions from it. This encryption key is derived from the DH shared secret without the stored state. [0020] When encrypting we do not store the private key used to produce the DH shared secret. This implies that the sender cannot decrypt his own sent messages but neither the adversary can decrypt outgoing messages based on a snapshot from sender's computer. [0021] The protocol has recovered when the last snapshot the attacker has does not contain the private key whose corresponding public key will be used in the next encrypted message to be received. Consider the case where the persons involved encrypt and decrypt messages in turns (they decrypt a message and then send a reply) and the snapshot is obtained from one computer. The adversary can decrypt depending on the timing of the snapshot either 0 or 1 message until the protocol recovers. If messages are not exchanged in turns but many messages are received before a new one is sent it may also happen that adversary can't decrypt a single message. If the timing of the snapshot is better messages can be decrypted until the sender receives new public keys. [0022] Two of the new public keys in a message are intended for the receiver of the message to be used in his next sendings as DH counterparts. One of the keys is used only once in a DH calculation, the other one is used many times if no newer public keys are available. The usage of the one-time key prevents in certain situations the attacker of using an older snapshot in order to decrypt more messages than a newer snapshot enables. [0023] All the messages are signed using the digital signature method of the underlying public key scheme. The private/public key pair used is selected to be the other one than the one-time one of the latest public keys the intended receiver is known to posses. The plaintext ends with a mac-value. The PRG produces the corresponding mac-key together with the encyption/decryption key. The verification of the mac ensures that proper symmetric keys were used and the plaintext was created by the sender and was decrypted successfully. Note that the protocol relies on the states on different computers being updated in synchronous way, thus e.g. a restored backup of the security data may destroy this dependency. [0024] As extra countermeasure against certain kinds of attacks the two new public keys in a message can be encrypted together with the plaintext. Note that then an attacker cannot know a DH counterpart unless he has decrypted a previous message or obtained a proper snapshot. This provides protection if the underlying public key scheme or its implementation has weaknesses. Note also that the protocol itself without this encryption of public keys provides same kind of protection: a DH shared secret alone is not sufficient to produce a symmetric key—the previous stored state is also required. [0025] The underlying public key scheme might be a RSA one or based on elliptic curves or some other scheme. On elliptic curves the public key generation can be done on tens of milliseconds even if currently adequate field size is used. [0026] To decrypt more messages the attacker may want to launch a so-called man in the middle attack. This is easiest to the attacker if he succeeds in obtaining the snapshots of both communication parties' security data at the same time. Lets assume the parties involved are Alice and Bob, the adversary being Charlie. Alice now sends a message to Bob. Charlie captures the message and uses the snapshot of Bob's data to decrypt it and then uses Alice's snapshot to encrypt it again for Bob and only then passes the message to Bob. This can continue as long as the adversary wishes. Every message from Bob and from Alice can and must be decrypted/encrypted. Another way to start this kind of attack is to modify the security data on Alice's computer and send a message to Alice pretending it being from Bob or to create a message to Bob based on the knowledge obtained from a snapshot from Alice's computer. The man in the middle attack can be detected if a cryptographic hash value (used as a checksum) is computed from the message. The hash value on Alice's computer of a message sent from Alice's computer will differ from that of at Bob's computer if there is an active man in the middle attack. If the adversary wants to stop this attack and not arouse any suspicion he has to modify the security data on at least one of the computers involved. If during active man in the middle attack one of the messages is not captured and changed by the attacker the receiver will not be able to verify its signature. DETAILED DESCRIPTION [0027] A message has three parts: public, history and the text part. [0028] The public part consists of: identifier of the receiver, message number, a new public key (called refresher), identifier of the refresher's Diffie-Hellman counterpart (called DH identifier), 2 new public keys (called one-time and repeater) and the message text part's starting position. As an option the one-time and repeater public keys can be placed together with the message's text and be thus encrypted. [0029] History part: number x, a list of x number of items each consisting of a public key and the corresponding DH identifier (this list of items is called history data). [0030] Text part: the message text, optionally the one-time and the repeater public keys may be placed here, a mac-value. [0031] The message ends with a digital signature of the whole message. [0032] New to the current state of the art is that a message contains history data: a list of recently used public keys and their DH counterparts. Using this history data it is possible to have a state in both the sender's and the receiver's computer that goes through same values even if some of the messages sent are never received or not decrypted. The reader should also notify the usage of two different kinds of public keys: a one-time one and one that is used if no newer public keys are available. [0033] The public part is not encrypted, others are but with different symmetric keys. The history part's key is derived from the public part's DH shared secret without the use of the so-called key generator. The text part's key is derived using the key generator. A block cipher performs the encryptions/decryptions. [0034] A security data storage (store) hosts for each messaging contact: [0035] Sent keys collection (a public and private key, a message number that carried the keys) [0036] Signature keys collection (a public key for signature verification and a message number) [0037] Waiting keys collection (a message number, a public key for signature verification, a symmetric key and a mac-key) [0038] History data items (each item consisting of a message number and a sent public key and the DH identifier of the corresponding public key) [0039] Two states: one for sending and one for receiving (a state has two blocks b 0 and b 1 , their size is the size of a DH shared secret). [0040] Also stored are: [0041] Latest received one-time and repeater public keys and the message's number that carried them [0042] Latest sent repeater key the receiver is known to posses. [0043] This storage is in user's computer typically in encrypted form and a password or a passphrase is needed for its use. When the protocol is used for encryption or decryption this storage must be available to the protocol. If an attacker succeeds in obtaining the data in this storage in decrypted form he is said to have obtained an exposed snapshot (shortly snapshot) of the security data. [0044] A key generator produces a new state, the symmetric key for encryption or decryption and the mac-key for plaintext verification. The encryption/decryption key and mac-key are called shortly symmetric keys. Part of the key generator's input comes from the security data storage: the state, the other part of the input is a newly computed DH shared secret. The key generator uses a pseudorandom bit generator (PRG) to produce its output. We arrange so that the initial seed x 0 to the PRG will be unknown to the attacker if he either misses a state or a DH shared secret—the seed x 0 is set to be the xor'd value of both of them. This is a new construction compared to the current state of the art. [0045] The used PRG must have the following properties: the bits produced must be pseudorandom and unpredictable i.e. from the result it must be infeasible to derive the seed or another outputted bit from another ones, also if the seed is unknown the outputted bits must be infeasible to derive. [0046] We next describe one possible PRG. [0047] Let GL(r,x) be a function computing the Goldreich-Levin hard-core bit from bit vectors x and r, r and x being of equal length. The GL bit is defined to be the inner product of x and r modulo 2: (x 1 r 1 +x 2 r 2 + . . . +x n r n ) mod 2, where the indices are the corresponding bits of x and r. [0048] Let Enc(key,plaintext) be an encryption operation of a block cipher. [0049] Let blocks b 0 and b 1 be the old state, k be the number of bits in the old state and in the symmetric keys. Let dr i be the i'th derived pseudorandom bit and x a bit vector. [0050] Key generator—derive the new state and the symmetric keys: [0051] Produce a block unknown to the attacker if he misses b 0 or DH shared secret: [0052] x=b 0 xor DH shared secret [0053] Run the PRG: [0054] For i=1 to k [0055] dr i =GL(DH shared secret,x) [0056] x=Enc(x,b 1 ) [0057] End for [0058] The produced bits dr i , i=1 . . . k will form the new state and the symmetric keys. Note that the usage of the Enc-function is the usual way to construct a one-way hash function using a block cipher: to compute a one-way hash of x compute Enc(x,p) where p is some fixed known plaintext. In our case the fixed plaintext varies between invocations of this PRG but stays the same during a specific invocation. If the attacker obtains a state s m and the next state s m+1 but misses a DH shared secret he still cannot run the PRG forward from s m . From the produced state s m+1 due to the pseudo-randomness of the hard-core bits he cannot derive other produced bits (the symmetric keys) or the initial seed x. If the b 1 would be the same during all invocations of this PRG (if b 1 is hard coded in the program) the attacker could without obtaining a snapshot perhaps try to guess the initial x (the result of the xor-operation). Now he has to obtain the snapshot and guess the initial x or without a snapshot guess both initial x and b 1 . The properties of this PRG allow the usage of the block b 1 and the DH shared secret in producing the outputted bits without compromising the unpredictability and pseudorandomness of the results. [0059] Consider now sending a message. Three new public keys are generated (called one-time, repeater and refresher). These keys are randomly (pseudorandomly) generated i.e. randomness is collected from some source and a pseudorandom bit generator produces the keys, then the seed is destroyed. The used PRG can be of a Blum-Micali Goldreich-Levin type or a different one—essential is that the seed is destroyed and that a private key cannot be determined from another one. [0060] This message's number is set to be one greater than the latest one sent. The generated one-time and repeater public keys are placed into their places in the message and the one-time private key and the repeater private key are stored in the sent keys collection. The refresher key is placed into its place in the message, however its private key is not placed into the store. [0061] From the store the message receiver's latest one-time and repeater public keys are fetched together with the message's number that carried them. If the receiver's one-time key has not been used before when sending then it is used as the DH counterpart otherwise the receiver's repeater key is used. The DH shared secret is computed with the receiver's selected key and with the sender's refresher key. In the public part of the message the DH identifier is set to be the message number that carried the DH counterpart and a value indicating whether the one-time or repeater key is used. When the shared secret has been computed the private key of the sender's refresher key is destroyed without it being stored. This will have the implication that the sender cannot decrypt messages sent from him, but neither can the adversary use a snapshot to decrypt outgoing messages. Adversary's possibilities are limited to incoming messages. [0062] Next from the store the history data items for the receiver are fetched and copied into the message. A symmetric key is derived from the DH shared secret (by e.g. computing its hash value) and the history part of the message is encrypted with this key. The new history data to be stored is build by adding this message's number and the refresher public key and the identifier of its DH counterpart to the top of the old history data. The message text part's starting position field in the message's public part is adjusted based on the size of the history part. [0063] Next the key generator is used the input being: the state for sending messages and the just computed DH shared secret. The new generated state is stored and the outputted symmetric mac-key is used to calculate text's mac-value (if the option of placing the one-time and repeater public keys together with the text is used then they are also included in this mac) and a block cipher encrypts the message text part using the produced encryption key. [0064] The whole message is digitally signed. The private/public key pair used in signing is selected to be the sender's latest repeater key the receiver is known to posses. The receiver's latest repeater public key and this message's number that is being sent are stored in the signature keys collection. [0065] Consider now decrypting a message. Based on a comparison between this message's number and the greatest number decrypted so far we consider three cases: 1) This message's number is one greater; 2) This message's number is two or more greater; 3) This message's number is less. [0066] If cases 1 or 2 apply then a message number x is extracted from the public part's DH identifier. From the store's signature keys collection a public key is fetched based on this number x. The signature at the end of the message is verified using this public key. If the signature does not verify the decryption is abandoned. [0067] The private key identified from the DH identifier is fetched from the store's sent keys collection. The DH shared secret between the fetched key and message's refresher public key is computed and a symmetric key is derived from it in order to be able to decrypt the history part of the message. [0068] If we are on case 1 then the state for receiving is fetched from store and the key generator uses the state and the DH shared secret to generate the new state and to output the symmetric keys. The outputted symmetric key is used by a block cipher to decrypt the message's text part. The mac-key produced is used to calculate a mac-value of the plaintext. The calculated mac-value is checked against the value found after the plaintext and if found being different the decryption phase is abandoned. The new state is stored. The received new public keys (one-time and repeater) are now the latest ones and they are stored. The latest repeater key the sender is known to posses is now set to be the repeater key that was in the message x when x was sent (the key is fetched from the sent keys collection). [0069] If we are on case 2 there are messages that have not been decrypted between the latest decrypted one and this message. The history part of this received message is decrypted and the key generator will be run to produce the symmetric keys for each message between the latest decrypted one and this message. From the history data list the first not yet processed refresher key and its DH identifier are identified based on the message number in the DH identifier. The list is processed each item in turn and the key generator is run to produce the next state and the symmetric keys. At the same time also a public key is determined that must be used to verify the signature of the message in question. For each message the generated keys and signature verification public key will be stored in the waiting keys collection together with the message number in question. This storing into the waiting keys collection will actually take place only after this message's mac-value has been verified. When the last item in history data has been processed the current message's DH shared secret and the state produced by the iteration on history data are inputted to the key generator. The outputted symmetric keys are used to decrypt and verify this message's text. If the mac-value is not verified no storing is performed and the decryption is abandoned otherwise the storing into the waiting keys collection is performed and the last generated state is also stored. The received new public keys (one-time and repeater) are now the latest ones and they are stored. [0070] If cases 1 or 2 apply then it may happen that after the decryption several items in the store can be removed. Let x be the message number extracted from this message's public part's DH identifier. Sent keys collection: an item with message number less than x is removed. The one-time private key of message number x is removed if it exists in the collection. History data: an item whose message number is less or equal to x is removed. Signature keys collection: every item whose message number is less than x is removed. [0071] If case 3 applies the store's waiting keys collection is used to provide the signature verification public key and the symmetric key for the message text's decryption. After signature verification and the text part's decryption and plaintext's mac value's verification the information relating to this message number in the waiting keys collection is removed. Please note that neither the history part nor the refresher key is studied in this case. The message text's starting position can be determined from the corresponding field in the public part of the message. [0072] To clarify the effect of using the one-time key consider the following situation: Charlie obtains a snapshot of Alice's security data before Alice encrypts a message to Bob. The private keys of the new public keys in the Alice's message are thus not in the obtained snapshot. Now Bob responds with many messages to Alice before decrypting a newer message from Alice. Alice decrypts the replies in order the first one being the message x. Now Charlie obtains another snapshot before Alice decrypts the message number y in the middle of Bob's responses. Charlie has now the state and private key needed to decrypt Bob's message y and messages from y forward. However, Charlie cannot go backwards in the state chain and thus the message x and messages before y cannot be decrypted based on the newer snapshot. The older snapshot exists but the problem from Charlie's viewpoint is that when Alice decrypted the first message x she destroyed the one-time private key. Charlie cannot proceed forward from the older snapshot's state since a private key is missing. If there would not be this one-time key concept the private key used to decrypt messages x-y would enable Charlie to proceed forward from the older snapshot. If Alice would not decrypt the messages in order the situation would be still the same. The private key of the one-time key is destroyed when the state is iterated forward when processing the history data of a message. [0073] During the initialization of the protocol both parties send to each other a one-time public key and a repeater public key with message number 0. The keys are stored into the sent keys collection with message number 0. A receiver of a repeater public key stores it into the signature key collection with message number 0. The receiver of a one-time and repeater keys stores them as the latest ones. Store's latest sent repeater key the receiver is known to posses is set be the just sent repeater key. [0074] The states' initial values are determined by a DH exchange, this public key is in the same message that delivers the first one-time and repeater keys. Note that the number of blocks in the state depends on the requirements of the used PRG. In the following we assume that the state consists of two blocks, if this is not the case the arrangements can be easily altered according to the number of blocks used. Let c 1 , c 2 , c 3 and c 4 be fixed blocks of data, their size being the size of the state's block and let Enc(key,plaintext) be an encryption operation of a block cipher. If the public key used to initialize the states is bigger than the other public keys then a one-way hash function is used to produce either one block dh 1 or two blocks dh 1 and dh 2 from its DH shared secret. If there is one block dh 1 available then Alice's state for sending to Bob is b 0 =Enc(dh 1 ,c 1 ), b 1 =Enc(dh 1 ,c 2 ) which is also Bob's state for receiving from Alice. Bob's state for sending to Alice is b 0 =Enc(dh 1 ,c 3 ), b 1 =Enc(dh 1 ,c 4 ), which is also Alice's state for receiving from Bob. If two blocks dh 1 and dh 2 are available then Alice's state for sending to Bob is b 0 =Enc(dh 1 ,c 1 ), b l =Enc(dh 2 ,c 2 ) which is also Bob's state for receiving from Alice. Bob's state for sending to Alice is b 0 =Enc(dh 1 ,c 3 ), b 1 =Enc(dh 2 ,c 4 ), which is also Alice's state for receiving from Bob. [0075] To convince the parties that the initialization messages are not altered they either a) are accompanied with a certificate and signed with the public key the certificate certifies or b) the parties compute a cryptographic checksum (hash value) of the message sent and received and ensure each other that the checksum is the same at both ends—this can be done by e.g. using voice contact. [0076] Please note that the history part of a message varies in size when messages are sent and received. Although the history part is encrypted a casual observer might draw some conclusions based on its size. To prevent this the history part may be set to have a specific predetermined fixed size and if the actual required size exceeds this then a random value from some predetermined range is added to the required size. Let x be the most recently sent message by Alice. A message received by Alice which uses one of the public keys in message x as DH counterpart empties the history data of Alice. The next message Alice sends would have history data of zero size. The above-described method can be used to hide e.g. this information. [0077] Please note that the message number in the public part of the message reveals how many messages the sender has created. If a casual observer then sees messages he can draw some conclusions on the messaging behaviour of the parties. To hide the starting point of the message number it can be started from some number that is derived from the DH shared secret in the protocol initialization phase. [0078] Note also that if the one-time and the repeater public keys are placed in the message's text part then an adversary has no knowledge of a refresher key's DH public counterpart unless he has succeeded in decrypting the required message or has obtained a suitable snapshot. This provides protection if the underlying public key scheme or its implementation has weaknesses. The protocol itself also gives same kind of protection since a solved DH shared secret is not sufficient to produce a symmetric key—the proper stored state is also required. [0079] The message's public part contains the starting point of the message's text part thus revealing the size of the history part. It is possible not to place this starting point information in the public part and thus avoid using the technique to hide the size of the history data. The solution is to add this starting point information into a list item of the history part's list. Now every list item contains also the starting point of the corresponding message's text part. During encryption operation when a new list item is added on top of the history data the current message's text part's starting point is stored into the added item. [0080] If during a decryption the current message's number is seen to be greater than the latest decrypted one then the size of the current message's history part can be determined by decrypting the first one of its blocks, now the stored number—which tells how many items there are in the list—is used to compute the size of the history part. [0081] If during a decryption the history part is used to produce symmetric keys then this starting point found in a list item is stored into the waiting keys collection together with the symmetric keys and the signature verification key. When the waiting keys collection is used to decrypt a message this stored starting point tells where to start the decryption of the text part. Using this solution there is no need to try to hide the history part's size from a casual observer.

The presented messaging protocol uses three new public keys in a signed and encrypted message to achieve backward security and recovery in an environment where an attacker now and then obtains the security parameters in exposed, decrypted form. Backward security is understood to mean that an adversary cannot decrypt those captured encrypted messages that the user has decrypted prior the exposure. The recovery of the protocol means that the attacker at some point of time after the exposure cannot any more decrypt messages created after the exposure. The invention can be used e.g. in encrypted email communication. New to the current state of the art is that a message contains history data: a list of recently used public keys and their Diffie-Hellman counterparts. Also new is the usage of a stored and pseudorandomly changing data used together with a just computed Diffie-Hellman shared secret to provide a value that an attacker cannot produce if he does not have a proper exposed security data and the private key required to compute the Diffie-Hellman shared secret.

This application is a continuation-in-part of Ser. No. 07/184,721 filed on Apr. 22, 1988, now U.S. Pat. No. 5,006,309. BACKGROUND OF THE INVENTION The present invention is directed toward a method and a disposable device for use in an automated solid-phase diagnostic assay. The device is designed to have a plurality of two well pairs, one of each well pairs is where a sample material can be incubated with reagents to perform a solid-phase assay and another in which the results can be read. The reaction mixture is transferred from the first well, the incubation well, to the second well, the read well by a non-contact means using jets of fluid to move the reactants between the two wells. The disposable device has surface features surrounding each well pair that mates with a chemiluminescent reader head in such a way that a light-tight seal is created to allow low-light level measurements. Associated also with each well pair a means for immobilizing and retaining the reaction products, a means for removal of excess reactants and wash solutions and a vent hole to vent air displaced by fluids added into the device. Techniques for performing an immunoassay are generally known in the art. For example, conventional enzyme immunoassay procedures involve a series of steps wherein an analyte in sample material is initially bound to a corresponding antigen or antibody reagent. A second antigen or antibody is then introduced into the sample which has been labeled with an enzyme or other substance capable of being detected directly or after addition of a suitable reagent such as a chromogenic or fluorogenic substrate or a trigger solution for activating chemiluminescence. The generated signal is then read to indicate the absence or presence of the antigen or the antibody in the sample. Solid phase immunoassay procedures are preferred over other diagnostic methods because of their specificity and sensitivity as interfering substances can washed away before optical readout. One form of a conventional solid-phase immunoassay is a "sandwich assay" which involves contacting a test sample suspected of containing an antibody or antigen with a material which has attached to it a protein or another substance capable of binding the antigen or the antibody to the surface of the support. After the antibody or antigen is bound to the support material it is treated with a second antigen or antibody, which is conjugated with an enzyme, a fluorophore or a chemiluminescent label. The second antigen or antibody then becomes bound to the corresponding antibody or antigen on the support. Following one or more washing steps to remove any unbound material in an enzyme immunoassay, an indicator substance, for example, a chromogenic substrate, is added which reads with the enzyme to produce a color change. The color change can be observed visually or more preferably by an instrument to indicate the presence or absence of the antibody or antigen in the sample. For solid-phase fluorescence or chemiluminescence immunoassays, fluorescent labeled moieties can be monitored by using excitation at an appropriate wavelength, while chemiluminescent labeled antigens or antibodies can be followed after reaction by chemically activating the chemiluminescent labels to generate light which can be detected by photometric means. Many procedures and apparatus have been designed to perform solid-phase immunoassays. U.S. Pat. No. 4,632,910 discloses an apparatus having a porous filter containing a bound receptor for complexing an analyte. In this apparatus an absorbent material is positioned below the porous filter to assist the fluid sample in flowing through the filter. A labeled antibody is then added to the porous filter to detect the presence or absence of the analyte. This approach leads to assays with limited sensitivities as the sample and conjugate incubation takes place on the same matrix. None-specific binding of the sample and conjugate to the porous matrix can occur and contribute to the background of the assay and limits its sensitivity. In another approach, European Patent Application No. 0131934 discloses an assay device having a plurality of aligned adjacent incubation wells located on its top surface which empty through a filter membrane located above a waste reservoir. U.S. Pat. No. 4,652,533 discloses an assay method using such a device. A solid-phase fluorescent immunoassay reaction mixture is placed in the well and drawn through the membrane by applying reduced pressure to the waste reservoir to separate a solid-phase reaction product from a liquid-phase reactants so that the solid-phase reaction product can be observed. This approach, however, has serious limitations. First, it is limited to use of microparticles as a capture phase. Secondly, the sample, conjugate and microparticles are incubated in the same incubation well that the optical reading takes place. Non-specific binding of sample and conjugate, labeled antigen or antibody, to the membrane filter in the reading well and the wall of the well can occur and contribute to the background of the assay and thus limits its sensitivity. Third, because of using a common vacuum manifold to a plurality of filters, a pinhole in one of the wells will lead to air leaking through this well and no filteration for other wells in the disposable reaction tray. Thirdly, such a disposable device cannot be used for chemiluminescence immunoassay measurements where extreme light tight conditions around each well are required. Other microparticles vacuum filteration devices for immunoassays are available commercially such as Millititer® Plate from Millipore Corporation, Bedford, Mass. Other methods for performing a solid-phase immunoassay are disclosed in U.S. Pat. Nos. 4,587,102, and 4,552,839, and European Patent Application 0200381. These references generally disclose procedures for employing particles having a receptor to bind an analyte which is subsequently labeled and deposited on a matrix or other support system. The particles complex is treated with an indicator substance to indicate the presence or absence of an analyte. While many immunoassay procedures and devices have proved useful, better procedures and devices are continually being sought to improve reliability, efficiency and sensitivity. The present invention provides all of these improvements. SUMMARY OF THE INVENTION In one aspect, the present invention is directed toward a device suitable for performing an automated solid-phase diagnostic assay. The ability to perform an automated assay contributes to increased reliability and efficiency. The device of the present invention comprises a plurality of well pairs, one well of each well pair is a shallow incubation well in which a sample material can be treated with reagents to perform a solid-phase assay and the other well is a read well for retaining and immobilizing the formed immune complex, and in which the results of the immunochemical reaction can be read. The device is designed to allow for the transfer of the sample and reagent mixture from the shallow sample incubation well to the read well via a communicating passage. Separating the incubation well from the read well decreases the possibility of non-specific binding of the sample components in the read well and improves assay sensitivity. The separation and read well has an entrance port and a means for holding a quantity of sample and reagent mixtures positioned over a fibrous matrix which retains and immobilizes the resultant immune complexes. The fibrous matrix is composed of fibers having an average spatial separation greater than 5 microns. Separation of the immune complex on the porous element can be affected by using latex microparticles with antibodies or antigens immobilized on its surface as the capturing solid phase and separating them from the reaction mixture by their physical adhesion to the fibrous pad. Microparticles used in this process have diameters smaller than the spatial separation between the fibers of the pad. Another preferred method of separation is that which is described in co-pending U.S. patent application Ser. No. 150,278 (filed Jan. 29, 1988) and U.S. patent application Ser. No. 375,029 (filed Jul. 7, 1989), both of which are incorporated by reference herein, directed to the use of ion capture separation wherein the fiber pad is treated with a cationic detergent to render the fibers positively charged. The antibody, or antigen, for the assay in question is chemically attached to a poly-anionic acid such as polyglutamic acid or polyacrylic acid. Separation of the immunochemical reaction product will be affected by the electrostatic interaction between the positively charged pad and the negatively charged poly-anion/ immune complex. The read well further comprises a fluid removal means positioned below the fibrous matrix to enhance the flow of sample and assay reaction mixtures through the fibrous matrix. A preferred means of fluid removal is the use of an absorbant pad in intimate contact with the fibrous matrix. The present invention also provides for a method of manipulating reaction mixtures without physically contacting the reaction mixture with a pipette tip or other mechanically transfer means. Thus contamination of the assay and apparatus is avoided which increases the sensitivity and accuracy of the assay. This is achieved by washing away the reaction mixture from the shallow incubation well into the read well by injecting wash solution into the incubation well from a series of nozzles at high speed. Injectors are directed at a specific angle to the shallow incubation well. Another preferred embodiment of this invention is to use such device for performing chemiluminescence immunoassays. Thus the disposable device of the present invention has molded surface features surrounding each incubation well/read well pair that mates with a chemiluminescent detector in such a way that a light-tight seal is created to allow low-light level measurements for high sensitivity assays. Associated with each incubation well/read well pair in the disposable device is a hole to vent the air originally entrapped in the absorbant pad and is displaced by the reaction mixture and wash solutions. The present invention also provides various methods for performing a solid-phase assay in the device using either microparticle or ion capture separation techniques. In the following example the term capture agent will be used to describe microparticles coated with an immunochemical reactant or a polyanion attached to an immunochemical reactant. In the former case the fibrous pad may be treated with substances that facilitate adherence to the microparticles and flow of the remaining fluids. In the latter case the fibrous pad will be treated with cationic materials that facilitate attachment of the polyanion-immunoreactant complex to the matrix. One method for performing a sandwich immunoassay in accordance with the invention comprises the following steps: a) incubating the sample material with an analyte specific conjugate in the shallow incubation well to form an analyte/conjugate complex; b) simultaneously adding a capture agent to act as a solid phase, incubating the reaction mixture for a time period and at a temperature that maximize the formation of the immune complex and then washing the capture agent/analyte/conjugate complex into the read well. c) adding additional wash solution to the read well to transfer the capture agent analyte/conjugate complex into the fibrous matrix where it is retained and immobilized; d) adding a substance capable of producing a signal in the presence of the capture agent analyte/conjugate complex to the fibrous matrix; and e) detecting the signal produced. Alternatively, steps a) can be performed by simultaneously adding the capture agent, sample and analyte specific conjugate in the shallow incubation well and then washing the mixture into the read well. In another alternative method, step b) can be performed by contacting the analyte/conjugate complex with capture agent in the shallow incubation well to form a microparticle analyte/conjugate complex and then washing this complex into the read well. In yet another another embodiment step a) can be performed by incubating a sample with the capture agent in the shallow incubation well and then washing the capture agent analyte complex into the read well. Alternatively, step b) can be performed by incubating a capture agent analyte complex with an analyte specific conjugate to form a capture agent analyte/conjugate complex, which is washed into the read wall. The disposable device can also be employed to conduct competitive assays. A competitive assay comprises incubating a sample and capture agent with a labeled antigen in the shallow incubation well, washing the reaction mixture into the read well and detecting the product formed. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a top plane view for one embodiment of the diagnostic device. FIG. 2 is a side view and cross section of the diagnostic device 10 of FIG. 1 cut along the short axis. FIG. 3 is a side view and cross section of the diagnostic device 10 of FIG. 1 cut along the long axis. FIG. 4 shows a side view and cross section of a single well pair of diagnostic device 10 positioned for transfer under device 30. FIG. 4a shows a side view and cross section of diagnostic device 10 positioned for transfer under device 30. FIG. 5a shows an expanded top vie of device 30. FIG. 5b shows a top view of device 30. FIG. 6 shows the transport mechanism for moving device 10 under the transfer device 30. DETAILED DESCRIPTION OF THE INVENTION The present invention is directed toward a device for performing a solid-phase immunoassay and methods for performing solid phase immunoassays with this device. The device is disposable and is suitable for use with an apparatus having programmed instructions and means for adding sample and reagents, injecting a wash solution to transfer the assay reaction mixture from the incubation well to the read well and for optically reading the results of the assay. The present invention also provides for a method of transferring reaction mixture from incubation well to read well without physically contacting the reaction mixture with a pipette or other transfer means. Thus contamination of the assay and apparatus is avoided which increases the sensitivity and accuracy of the assay. Sensitivity of the assay is further enhanced by performing incubation and read steps in two separate wells thus decreasing the possibility of non-specific binding of conjugate in the read well and decreasing background signal. The present invention also provides various methods for performing a solid-phase assay employing the disposable device and the method of transfer and washing of reactants. The device is designed to be employed in a variety of solid-phase diagnostic assays such as sandwich or competitive binding assays. The device is also designed so that it can be used for fluorescence or colorimetric detection methods. In addition, a special feature is designed into this device to allow light tight seal for chemiluminescence measurements. Further the device of the present invention can be used for microparticle capture or ion capture methods of separating the immunochemical reaction products. The device is molded to have sets of wells, each set comprises a shallow incubation well for receiving a sample which communicates through a sloping passage means with a read well for detecting the results of the assay procedure. Preferably, the device is molded of opaque polystyrene acrylonitrile-butadiene-styrene ter-polymer (ABS), polycarbonate, polyacrylates or some other moldable material which is inert to the assay components. Samples which can be assayed by the device include biological fluids such as whole blood, spinal fluid, urine, serum and plasma. It is also envisioned that other fluid samples of a non biological nature can be analyzed using the disposable device. The sample is placed either manually or mechanically into the shallow incubation well and reacted (hereinafter described) and after an appropriate time transferred and washed into the read well where the results of the assay are monitored or detected. In one embodiment of the present invention is the device 10 shown in FIGS. 1 and 2, having a plurality of the shallow incubation well 12, passage means 16 corresponding read wells 14 Each read well 14 has a holding means 20, a fibrous material 22 assembled into a square or a rectangular array. Each read well element has a separate porous fibrous matrix 22 and either a separate absorbent material element 24 or a common absorbent material pad, or layers of absorbent material pads. It can also be assembled in such a way that individual absorbent material elements 24 are in intimate contact with the fibrous matrix 22 on one end and with a common absorbent layer on the other end. Any of the absorbant material configurations is chosen to enhance diffusion of fluids away from the porous fibrous matrix 22. The array assembly is preferred where a high throughput instrument is desired. The surface feature 26 is an array of rectangular ribs each rectangle encloses an incubation well/read well pair and acts as a light seal when a chemiluminescence detector, with matching groove padded with compressible polymeric material, mates with it. Vent hole 28 is associated with each incubation well/read well pair. It vents out the air originally entrapped in the absorbent pad and is displaced by reaction mixture and transfer and wash solutions. Intimate contact with the porous matrix 22 and the absorbent material 24 by compressing the absorbent material against the porous matrix using surface features 25 on the internal bottom surface of the disposable device 10. Shallow incubation well 12 can be semi-spherical, semi-cylindrical, toroidal or any complex curvature with no sharp corners. The largest radius of curvature of the shallow incubation well is along the axis connecting the incubation well to the read well. Dimensions of the shallow incubation well 12 are chosen to maximize the volume of reaction mixture that can be incubated in the well, without having a steep fluid exit angle. A high fluid exit angle requires high wash solution injection speeds. Under these conditions fluids from incubation wells may overshoot the read well as they are transferred. On the other hand low exit angles may lead to self transfer or spilling of reaction mixture into the read well. Choice of dimensions and their relationship to fluid properties can be easily calculated by those skilled in the art. Transfer takes place by injecting wash fluid at the side of the shallow incubation well 12, farthest from the read well 14 using a transfer and wash device 30 shown in FIG. 4. A group of nozzles 32 are positioned close to the surface of the incubation well 12 to inject wash solution. Said solution is injected into the shallow incubation well 12 at a small angle to the tangent to the surface of the well at its region of intersection with the meniscus of the reaction mixture. Angle between direction of wash solution injection and tangent to shallow incubation well surface are generally kept below 45°. Angles between 5° and 20° are preferred. Wash solution injection volumes and speeds at which it is injected into the shallow incubation well 12 depend on the reaction mixture volume needed to be transferred. Slow wash solution injection speeds into the shallow incubation well 12 may lead to a partial transfer and successive dilution to reaction mixture. Larger wash solution volumes will be required to complete the transfer, which in turn necessitates a larger capacity of absorbent material 24 and hence a larger size disposable. The other extreme of high wash solution injection speeds into the shallow incubation well 12, transferred reaction mixture may overshoot read well 14 and introduces the possibility of reaction mixture or wash solution splashing back towards the injectors and contaminating them. In other words, depth and curvature of shallow incubation well 12, angle of exit port 16 and volume and injection speed of wash solution are dependent on the total assay volume to be incubated in well 12. Total assay volume in turn is optimized to achieve the desired binding reaction under the constraints of assay conditions. Those who are skilled in the art of fluid dynamics can calculate and optimize these dimensions once the essence of this invention is understood. The read well 14 generally comprises a sloping down entrance port and holding means 20, a porous fibrous matrix 22, and an absorbent material 24. The entrance port and holding means 20 can be a molded portion of the device and preferably a funnel-like structure and is an integral part of the incubation well 14. The holding means 20 is designed with sloping sides which contact the upper surface of the fibrous matrix 22 and is sized to hold a sufficient amount of sample, conjugate material or other reagents to satisfy the requirements of the particular assay being performed. The holding means 20 should be sufficiently opaque or preferably made of black plastic material to decrease background interference with the optics system. Each pair of incubation wells and associated read well is surrounded by a raised portion, preferably in the form of a rib or a thin plastic wall 26 which is a molded feature of the disposable device and acts as a mating part for another feature on a chemiluminescence reader to create a light tight seal. The height of such light seal is 0.020 to 0.10 inches and preferably 0.04 to 0.08 inches. In a preferred embodiment of this invention is the transfer device 30 that is comprised of two sets of nozzles 32. Each set of nozzles is directed towards an incubation well of the reaction tray 10 that has two rows of incubation well/read well pairs. Each set of nozzles is connected to fluid distribution manifold 34 into which wash solution is injected via a stepper motor controlled pump. The first set of nozzles is directed towards the first incubation well of the plurality of well pairs and the second set of nozzles is directed into the second parallel incubation well and fluid flow is diverted to the second set of nozzles via a valve 36 using the same pump. Alternatively an independent pump can be used for each set of nozzles. Thus the transfer process can be performed on two parallel incubation wells either sequentially or simultaneously. A single pulse or several pulses of transfer solution are injected into the incubation well with a delay time between injections to allow the transferred fluids to drain from the read well 14. This prevents splashing and back washing of the reaction mixture from the read well into the incubation well, an action that can reduce transfer efficiency. Drainage time between fluid transfers can be 2 to 180 seconds, preferably 2 to 60 seconds and more preferably 2 to 15 seconds. In the same transfer device and located on top of the parallel read wells 14 is another set of nozzles 38, each nozzle is connected to a pump either directly or via a valve and can be used to deliver a reagent to the transferred and washed reaction mixture on the fibrous pad 22. Once such nozzle can be used for adding additional wash solution into the read well to transfer any capture agent analyte/conjugate complex on the walls of the retaining means 20 into the fibrous matrix 22 where it is retained and immobilized, this in turn decreases fluctuations in assay numbers due to varied amounts of retained immune complex. The same nozzle can be used to wet the fibrous pad with wash solution before transfer to improve fluid flow into the pad and the absorbent material. Another nozzle can be used for adding a second reagent to the transferred reaction mixture on the pad 22. The transfer and wash solution preferably contains a small amount of detergent in order to decrease the surface tension and improve wetting the plastic and facilitate transfer. Detergents such as Tween®, sodium dodecyl sulfate or lithium dodecyl sulfate can be used for this purpose. Other surface active agents can be contemplated and used by those skilled in the art. An alternate way to transfer reaction mixture from shallow incubation well 12 into read well 14 is to use a combination of air and wash solution nozzles. Alternating wash solution nozzles and compressed nozzles in the group of nozzles directed towards the wall of the shallow incubation well 12 and simultaneously activating them can affect the same transfer described previously. This saves in the fluid volume used in the assay and hence in the volume of fluids to be disposed of in the absorbent material 24. The transfer device 30 can be moved by robotic means and accurately positioned on subsequent incubation wells to affect transfer and wash of the reaction mixture. A preferred way to bring new wells under the transfer device 30 is to move the disposable device 10 in a controlled manner under the transfer device 30 using a mechanism 40, comprised of a timing belt 42 controlled by a stepper motor 44 and gear reduction system 45. A rectangular plastic log 46 pushes the disposable device 10 to new positions. Other means of moving the disposable device such as the use of linear actuators, metal belts or screw drives can be contemplated and used by those skilled in the art. The porous fibrous matrix 22 is a thin disk-like material positioned below the entrance port and holding means 20 to retain and immobilize a complex from which an assay signal can be read. The phrase "retain and immobilize" means that the captured/labeled immune complexes while upon the fibres of the material are not capable of substantial movement to positions elsewhere within the material, (i.e., to other fibers), and cannot be removed completely from the material without destroying the material. The pore size or spatial separation of the fibers comprising the fibrous matrix 22 is essential to the overall performance of the solid-phase immunoassay contemplated by the present invention. It must allow adequate void areas to assure the proper flow of reagents and sample through the fibrous matrix. Specifically, the spatial separation of the fibers must be larger than the diameter of the microparticles employed in a microparticle capture assay in such a way that after the microparticles are deposited on the fibrous matrix, the matrix is not blocked but instead remains porous. As used herein "porous" means that the matrix is and remains a material into which fluids can flow and can easily pass through without the need to apply vacuum or pressure to facilitate its flow. The fibrous material of the present invention can be chosen from any of a variety of materials such as glass, cellulose, nylon or other natural or synthetic fibrous material well known to those skilled in the art. A suitable material is H&V Product No. HC411 glass fiber filter paper, which has a nominal thickness of 0.055 inches and is commercially available from Hollingsworth and Vose Co., East Walpole, Mass. The thickness of such material is not critical, and is a matter of choice for one skilled in the art, largely based upon the properties of the sample being assayed, such as fluidity. The fibrous matrix 22 is positioned against the holding means 20 and above a means that functions to facilitate the transportation of fluid through the fibrous matrix. This can be a reservoir means to which reduced pressure is applied during or after the transfer, or an absorbent element made of any moisture or fluid-retaining material which effectively retains fluid passing through the fibrous matrix 22. A preferred embodiment of this invention is that an absorbent material 24 is positioned below the fibrous matrix 22 and is in intimate contact with the lower surface of porous matrix 22 in order to absorb any reagent that flows through the fibrous matrix. This contact assures rapid transportation of the reaction fluids through the fibrous matrix 22. The microparticles employed to perform the solid-phase immunoassay are selected to an average size that is preferably small enough such that they are suspendable in water or a sucrose solution to facilitate their coating with an antibody or antigen. The average individual size of the microparticles which can meet both of the above requirements is from about 0.1 to about 50 microns, more preferably from about 1 to about 10 microns in diameter. The microparticles can be selected from any suitable type of particulate material such as polystyrene, polymethylacrylate, polypropylene, latex, polytetrafluoroethylene, polyacrylonitrile, polycarbonate or similar materials. Uncoated microparticles can be employed for binding some analytes but in many situations the particles are coated with a substance for binding an analyte, e.g., antibody or antigen, or a combination thereof. The transfer and treatment of a sample with reagents in the device is preferably but not necessarily accomplished by automated means under computer control. Robotic arms can supply the necessary reagents by various transferring means communicating with reagent containers located external to the device and associated mechanisms. Most importantly instrument mechanism or robotic means can position a pipetting or jet means for directing a stream of wash solution into the shallow incubation well 12. Alternatively the assay device 10 can be placed on a conveyor where a timing belt can move it at precise time intervals to locations under automated pipettors, reagent dispensers transfer devices, washing devices or detectors. Whether a linear or circular motion is used to move the disposable, it is ultimately brought under a transfer device which successively injects transfer fluid into well 12 to wash the assay reaction mixture through passage means 16, into the read well 14. This particular feature of the device 10 prevents contamination of the automated apparatus or pipetting means as well as the assay reaction mixture. Also, because a pipette never needs to be washed to prevent cross contamination of other assays. For illustration purposes the following procedures are provided: In one form of a sandwich assay method a sample is added to the shallow incubation well and the device is placed on a transport means designed to hold a plurality of devices. Steps (a) through (e) may be performed by a microprocessor-controlled automated instrument or manually as follows: (a) an analyte-specific conjugate is added to the shallow well containing a sample to form a mixture which is incubated for a sufficient time to allow any analyte present to complex with the analyte specific conjugate; (b) microparticles are added to the mixture to form a microparticles analyte/conjugate complex; alternatively, the analyte/conjugate complex can be washed into the read well to which microparticles have been previously or simultaneously added; (c) the incubated microparticles analyte/conjugate complex is washed into the receiving port of the read well and washed with a suitable buffer or water to transport the complex into the porous fibrous matrix; (d) an indicator substance capable of producing a color change or other detectable signal in the presence of the microparticle analyte/conjugate complex is added to the read well; and (e) the assay signal is detected by optical means as a function of the presence or amount of analyte in the sample. In a variation on the above procedure, steps (a) and (b), i.e., formation of analyte/conjugate complex and formation of microparticle analayte/conjugate complex, respectively, can be performed simultaneously by adding the capture agent, sample and analyte-specific conjugate to the shallow incubation well and incubated. The complex is then washed into the read well. In the final step (e), detection of the signal produced in the read well varies with the type of label used. Thus for an enzyme labeled antigens or antibodies, a substrate solution is added in the read well and the product formed is detected by color development or generation of a fluorescent signal. For fluorophore labeled antigen or antibodies, direct excitation of fluorophore and detection of spontaneous or time resolved fluorescence signal is used. In the case of chemiluminescent labeled antigens or antibodies, detection is achieved by chemically activating the luminescent label and monitoring generated light. In all these methods of detection, either the total integrated signal over a period of time or the rate of change of signal over the observation period can be used to establish a standard curve for the assay and determine the concentration of analyte in unknown samples. In another version of a solid-phase sandwich assay procedure the automated or manual steps can be performed as follows: (a) a sample and capture agent are mixed together in the incubation well to form a complex of the microparticle and analyte; (b) the microparticle analyte complex is treated with an analyte specific conjugate and incubated to form a microparticle analyte/conjugate complex (alternatively steps (a) and (b) can be performed simultaneously by adding sample, capture agent and an analyte specific conjugate to the incubation well, incubating and washing the complex formed into the read well); (c) the complex is then then transported into the fibrous matrix by applying a wash of a suitable buffer or water through injector means; (d) an indicator substance capable of producing a signal in the presence of the microparticle analyte/conjugate complex is added to the read well to form an assay signal; (e) the assay signal is detected by optical means as a function of the presence or amount of analyte in the sample. In yet another solid-phase immunoassay approach the disposable device can be employed to perform a competitive binding assay. The automated or manual steps are as follows: (a) a sample is added to a known amount of labeled antigen and capture agent capable of binding a suspect antigen to form a mixture in a incubation well; (b) the mixture is washed into the read well where the capture agent become bound to the fibrous matrix; (c) the fibrous matrix is washed to remove unbound antigen; (d) an indicator substance is added to the read well to form an assay signal in the presence of the labeled antigen; and (e) the assay signal is detected by optical means as a function of the presence or amount of analyte in the sample. It should be apparent that many variations of the above steps can be designed to form the microparticles analyte/conjugate, complex which can be detected by optical means on the porous fibrous matrix. Generally the sandwich or competitive assay procedure and the choice of an analyte specific conjugate, and indicator substance are known to those skilled in the art and therefor are not discussed in great detail here. Instead, the present invention is directed toward the device described above and the method of transfer, and in a preferred embodiment to the device which is suitable for the automated performance of a solid-phase immunoassay process on a microprocessor-controlled automated instrument. This method of incubation in one component, fluid transfer, separation and signal generation in another compartment described in this invention is not limited to microparticle based immunoassays. Thus another preferred embodiment of the invention is to use an ion capture separation method as described above. The different procedures and examples described above for the use of microparticles as a capture phase can be used with ion capture, whereas a polyanionic material attached to a hapten, antigen or antibody is used as a capture agent in-place of the microparticles in each example. After transfer of the polyanionic material to the positively charged glass fiber pad, the immune complex is retained and immobilized on the glass fiber pad by ionic forces. Competitive binding ion capture immunoassay can be performed according to the method of the present invention. In this method the fibrous pad 22 is treated with a material that causes the surface to be positively charged, like water soluble polymeric materials with quaternary ammonium groups. Commercially available Celquat™ L-200 (from National Starch and Chemical Company, Bridgewater, N.J.) can be used for this purpose. The sample is incubated in the shallow incubation well with a labeled anti body for the analyte, a capture phrase is then added which is composed of the analyte molecule chemically bound to a an anionic polymer such as polyglutamic acid. After a second incubation the reaction mixture is transferred to the fibrous pad using injected transfer and wash solution. EXAMPLE I A disposable reaction tray was constructed according to the embodiments of this invention from two injection molded parts. The disposable tray was 6.800 inches long, 3.125 inches wide, and 0.800 inches high. The top part incorporated a two by eight rectangular array of the shallow incubation wells. Associated with each well is the funnel-like structure and the passage way between them described in the invention. The capacity of the incubation well is 280 micro liters and the capacity of the funnel is 480 micro liters. The center to center spacing of the two adjacent incubation wells or two adjacent funnels is 1.4173 inches (36 mm). The pitch of the rows of consecutive wells was 0.800 inches. The funnel-like structure has a cutting edge on the inside surface. The height of the surface feature for light sealing is 0.040 inches and its width is 0.040 inches. The vent hole was located 0.250 inches from the edge of the light baffle and was 0.060 inches in diameter. The top part was injection molded of black ABS. The bottom part was an injection molded piece of white ABS which mates with the top part and can be sonically welded to it. The top and bottom parts have surface features to fix a slab of absorbant material in place. The top part of the disposable device was turned upside down and a sheet of fibrous glass was placed inside the disposable, covering the bottom part of the read wells. The fibrous material was pressed against the cutting edges on the bottom of the funnel-like structures to cut individual filter pads for each well. The over-all diameter of each pad was 0.350 inches. The active area, facing the detector, was 0.210 inches in diameter. After the fiber pad was press-cut, the rest of the sheet was removed. This method of cutting the fibrous matrix, removing the excess material, and having an individual fibrous pad for each well is preferred as its prevents seepage of fluids between two adjacent wells and improves assay sensitivity. The absorbant material was placed in the top part of the disposable in contact with the glass fiber pads. It is a rectangular slab 6.5 inches long, 3 inches wide and 0.265 inches thick. The material was cellulose acetate manufactured by the American Filterona Company, Richmond, Va. The absorbant pad was pressed against the glass fiber disks by the bottom part. The surface features on the bottom part is in the form of a group of rings, each is concentric with the funnel-like structure and has a diameter of 0.665 inches and its rib is 0.120 inches high. The preferred design ring pushes the pad of absorbant material against the glass fibrous pad and assures intimate contact between the two pads. The two parts were assembled and welded using a Branson ultrasonic welder, Banson Ultrasonics, Danberry, Conn., with one horn optimized to fit the disposable device. A transfer and wash device similar to that described in the embodiments of this invention was constructed. Sample and reagents were incubated in the shallow incubation well. Wash solution was injected from an assembly of three adjacent nozzles 0.5 mm nominal diameter made of Teflon® tubing and connected to a machined polyacrylic manifold by minstac fittings from the Lee Company, Westbrook, Conn. The manifold was connected through a seloniod activated three way valve (Angar Scientific, Florham Park, N.J.) to a stepper motor controlled syringe pump. Nozzles were directed at an angle of 13° to the tangent to the shallow well surface at its point of intersection with reaction mixture surface. In this geometry nozzles were at a 60° angle to the horizontal plane. Wash solution was injected in the manifold at the rate of 1250 μL per second. The average linear injection speed was 2.1 m/second. The exit angle of fluid was 28°. Two aliquots 300 μL each of wash solution were injected into the incubation well to affect transfer. A delay time of 10 seconds was allowed between the two injections to allow for the fluids to drain through the pads. The capacity of the funnel was sufficient to prevent wash back. Transfer solutions preferably contained an amount of detergent such as 0.0250-0.1% Tween®, 0.025-0.1% sodium lauryl sulfate or lithium lauryl sulfate to prevent beading of fluids in the incubation well and facilitate fluid transfer. Three additional nozzles or were installed in the transfer device and centered on the pad. They were used either in groups or independently to wash the reaction mixture off the walls of the funnel into the pad or to deliver conjugate solution to the pad. EXAMPLE II The method of transfer and the function of the transfer device was tested by determining the efficiency of transfer of labeled chemiluminescent microparticles from the incubation well to the read well of the disposable device of example 1, using the following method: Acridinium sulfonamide labeled antibody or Hepatites B core antigen, pooled from lots prepared for clinical trials, concentration 5 μg/mL, was diluted in conjugate diluent, containing 50% fetal calf serum (Abbott Laboratories manufacturing stock), 2% human plasma, 0.1% Tween®-20, 0.1% ethylenediamine tetra acetic acid and 0.1% sodium azide in phosphate buffered saline, pH 6.8. The final conjugate concentration was 150 ng/mL. Carboxylated polystyrene microparticles coupled to antibody to Hepatites B core antigen as an undercoat and then with recombinant Hepatites B core antigen were pooled from lots prepared for clinical trials and contained 0.3% solids by weight. Microparticles were suspended in phosphate buffered saline (Abbott Laboratories, North Chicago, Ill.), pH 7.2, containing 16% sucrose. A 0.1% solution of Tween®-20 in phosphate buffered saline, pH 7.2, was used as a transfer solution. Luminescent microparticles for the determination of transfer efficiency were prepared by mixing 50 ml of conjugate solution and 50 ml of microparticles suspension. The reaction mixture was incubated in a wash bath at 40° C. for two hours. It was then let stand at room temperature for 24 hours to ensure complete binding of acridinium sulfonamide labeled antibodies to the antigen labeled microparticles. 100 μL of luminescent microparticles and 100 μL fetal calf serum were dispensed in each of the 16 shallow reaction wells of a disposable described in example 1. The disposable reaction tray was placed on a linear track and moved to a position where it was located under the transfer device of the present invention. The mixture was transferred from the shallow incubation well to the read well using two, 300 μL pulses of transfer and wash solution of a 0.1% Tween®-20 solution were injected at a linear speed of 2.1 m/second from three nozzles into the reaction well to transfer and wash the serum and microparticles onto the fiber glass pad. The disposable tray was linearly moved to a subsequent position where a chemiluminescence read head where each side of the disposable reaction tray was detected by an independent photomultiplier tube.0 The transfer and washed microparticles on the pad were triggered using 0.3% alkaline peroxide solution. The measured signal for each well was considered to correspond to the amount of the reaction mixture transferred from the reaction well to the read well by the method of the present invention. The mean and standard deviation for each eight wells on each side of the disposable were calculated. A base line was determined by dispensing 100 μL of luminescent microparticles on the fiber glass pad in each of the 16 read wells of a disposable reaction tray of example I and were allowed to drain through. 100 μL of fetal calf serum and 100 μL of de-ionized water were dispensed in each of the shallow reaction wells of the same disposable. The disposable reaction tray was placed on a linear track and moved to a position where it was located under a transfer device of the present invention. Two aliquots 300 μL each of a 0.1% Tween®-20 solution were injected at a linear speed of 2.1 m/second from three nozzles into the reaction well to transfer the serum and water mixture in order to wash the microparticles placed on the fiber glass pad with the same volume of fluids used in the first part of the experiment to transfer the microparticles serum mixture, and the disposable tray was moved on the same track by the same mechanism to the reader position under a read head. The washed microparticles on the pad were activated using alkaline peroxide solution and the resulting chemiluminescence signal was integrated for a period of six seconds. The mean and standard deviation of the signals generated in all eight wells in a sub-channel were calculated. The mean value of signal counts for the particles, manually pipetted on the pad corresponds to a 100% transfer. The efficiency of transfer was calculated by dividing the magnitude of the mean signal generated from the transferred microparticles each side by the signal representing 100% transfer on a corresponding side. Precision of transfer of the reaction mixture from the reaction well to the read well was determined by repeating each of the two previously described transfer and base-line experiments on three disposable trays. The mean percent transfer and the %CV of the percent transfer were calculated for each side of the three trays. The experiments were repeated for six independent transfer devices mounted on six incubation tunnel and each incubation tunnel was equipped with a read head and associated electronics were controlled by an 310 development system (Intel corporation, Sunnyvale, Calif.) Results from these studies are shown in table 1. In all instances the transfer efficiency was higher than 95% and the %CV of transfer was well below 5%. The reproducibility of the percent transfer figures indicate the validity of the fluid transfer method of the present invention. TABLE 1______________________________________Efficiency and precision of transfer of immune complex-coated latex particles Side A Side BUnit # % Transfer % CV % Transfer % CV______________________________________1 98.8 0.6 96.0 1.82 96.7 1.9 96.6 2.23 101.3 1.49 98.0 1.164 96.23 3.23 97.3 0.995 98.4 3.4 100.6 2.06 98.0 1.9 99.2 1.8______________________________________ EXAMPLE III Microparticle-Capture Competitive Binding Assay for Hepatitis B Anticore Antibody Materials Acridinium sulfonamide labeled antibody to Hepatites B core antigen, pooled from lots prepared for clinical trials, concentration 5 μg/mL, was diluted in conjugate diluent, containing 50% fetal calf serum (Abbott Laboratories manufacturing stock), 2% human plasma, 0.1% Tween®-20, 0.1% ethylenediamine tetra acetic acid and 0.1% sodium azide in phosphate buffered saline, pH 6.8. The final conjugate concentration was 150 ng/mL. Carboxylated polystyrene microparticles coupled to antibody to Hepatites B core antigen as an undercoat and then with recombinant Hepatites B core antigen, were pooled from lots prepared for clinical trials and contained 0.3% solids by weight. Microparticles were suspended in phosphate buffered saline (Abbott Laboratories manufacturing stock), pH 7.2, containing 16% sucrose. A 0.1% solution of Tween®-20 in phosphate buffered saline, pH 7.2, was used as a transfer solution. Samples were anti-core negative control and anti-core positive control from a commercial enzyme immunoassay kit Core panel control that has 50-60% inhibition as measured by a commercial enzyme immunoassay procedure (Corezyme, Abbott Laboratories, North Chicago, Ill.) Two procedures were followed: Procedure A Automated One Step Assay 100 μL of control or sample were pipetted into the shallow reaction wells of a disposable device using an automated pipettor. 50 μL acridinium labeled anti core antibodies and 50 μL of antigen coated latex particles were dispensed into each incubation well. The reaction mixture was incubated for 40 minutes in a heated tunnel at 40° C. with the disposable device moving into the tunnel by a timing belt at steps of 0.80 inches per second per step. It remains in position for 72 seconds for performing an assay step, then it steps again for one step at 0.80 inches per second. The reaction mixture was transferred and washed from shallow incubation well onto the porous fibrous matrix of read well as the disposable reached under the transfer device. Transfer was affected by injecting two pulses 300 μL each of 0.1% solution of Tween®-20 into the well from three nozzles in the transfer device. Each nozzle has a nominal diameter of 0.5 mm and the fluid was injected at an average linear speed of 2.1 m/second. A delay time of 12 seconds was allowed between the to pulses to assure drainage of the transferred solution through the pad The transferred microparticles, retained on the pad in the read well, were subsequently washed with three aliquots, 100 μl each, of wash solution. The disposable was moved on the timing belt to allow subsequent well pairs to be located under the transfer device and to transfer the reaction mixture and wash the microparticles retained and entrapped on the fibrous pad. The disposable device 10 was moved at the same rate to a read position where a chemiluminescence read head was lowered to mate with the walls surrounding the first two wells on the disposable to create a light-tight seal. The transferred and washed microparticles on the fibrous pad were activated using 0.3% alkaline peroxide solution. The measured signal for each well was considered to correspond to the amount of acridinium labeled conjugate attached to the microparticles. The end point was determined by calculating the percent inhibition of signal wherein % Inhibition=100 (Mean of Negative Control-Mean of Sample)/(Mean of Negative Control-Mean of Positive Control). A % inhibition of 50% and higher was taken as positive and a % inhibition less than 50% was assigned as negative. Data are tabulated in Table 1. Reproducibility of the percent inhibition figures indicate the validity of the fluid transfer method. Agreement with the standard enzyme immunoassay method shows that a heterogeneous immunoassay can be performed using the method and device of the present invention. TABLE 2__________________________________________________________________________A One-Step Microparticle Capture Competitive BindingHepatites B Anticore Antibody AssaySide A Side BMean MeanSampleCounts SD % I SD Counts SD % I SD__________________________________________________________________________Negative37833 1028 -1.5 3.0 35039 772 -0.26 2.4Control(n = 71)n = 69)Positive 2657 122 100.8 0.35 2174 109 100.7 0.34Control(n = 7)Panel19106 884 52.8 2.58 17126 462 54.73 1.41(n = 7)__________________________________________________________________________ Data from instrument #2 validation, Lab notebook #35601 pages 89-99 Procedure B Automated Two Step Assay 100 μL of control or sample were pipetted into the shallow reaction wells of a disposable device 50 μL 50 mM cysteine in a diluent containing 10 mM EDTA and 0.01% gentamicin, and 50 μL of antigen coated latex particles were dispensed into each incubation well. The reaction mixture was incubated for 20 minutes in a heated tunnel at 40° C. with the disposable device moving into the tunnel using the same mechanism described for the one step procedure. As the disposable reached under the transfer device the reaction mixture was transferred and washed from shallow incubation well onto the porous fibrous matrix of read well as described in the previous example. A 12 seconds delay was allowed for the transfer and wash solution to drain down the absorbant pad. 50 μL acridinium labeled anti HBc antibodies were dispensed on each fibrous pad from one of the nozzles located in the transfer device and directed on the center of the read well. The disposable was moved on the timing belt to allow subsequent well pairs to be located under the transfer device and to affect transfer of the reaction mixture. The disposable device was incubated for 20 more minutes in the tunnel using the same moving timing belt as it is moved to a washing position. The transferred microparticles, retained on the pad in the read well, and the excess acridinium labeled antibodies were subsequently washed with three 100 μl aliquots, of wash solution. The disposable device was moved at the same rate to a read position, the transferred and washed microparticles on the pad were triggered using 0.3% alkaline peroxide solution and the chemiluminescence signal was integrated for six seconds. The measured signal for each well was considered to correspond to the amount of acridinium labeled conjugate attached to the microparticles. A percent inhibition of 50% and higher was taken as positive and a percent inhibition less than 50% was assigned as negative. The cut-off value was set from performing the assay on negative population (200 samples that were confirmed negative for the antibody to Hepatites B core antigen using an enzyme linked immunosorbent assay ELISA procedure. TABLE 3__________________________________________________________________________A One-Step Microparticle Capture Competitive BindingHepatites B Anticore Antibody AssaySide A Side BMean MeanSampleCounts SD % I SD Counts SD % I SD__________________________________________________________________________Negative31610 1066 0.4 3.8 26839 583 -1.3 2.5Control(n = 70)Positive 3399 391 101.7 1.4 3260 474 100.3 2.0Control(n = 7)Panel15452 988 58.4 3.5 14102 355 53.6 1.5(n = 7)__________________________________________________________________________ EXAMPLE IV Ion-Capture Based Competitive Binding Hapten CLIA This example shows the use of the device and method of this invention in a competitive binding assay for the abused drug phenylcyclidine (PCP) in urine employing ion capture immunoassay procedures described above. The formation of the immune complex in the shallow reaction well of the disposable device of this invention involves the use of an anionic polymer as a capture agent. The reaction mixture is transferred to the read well of said device and and tan immunochemical reaction product is immobilized by ionic forces on the fibrous pad of said device that has been previously treated with a solution of a cationic polymer. Anti-phenylclidine antibodies were labeled with acridinium sulfonamide using EDAC coupling procedures. Prewet and transfer solutions were IMx buffer (Abbott Laboratories, North Chicago, Ill.) containing 25 mM Tris,). 0.3M sodium chloride, 0.1% sodium azide, pH 7.2. The cationic polymer was a 0.5% aqueous solution of Celquat™ L-200 (National Starch and Chemical Company; Bridgewater, N.J.) in 10 mM sodium chloride. The capture agent phenylcyclidine-polyglutamic acid was prepared according to the following steps: 1 gm of polyglutamic acid sodium salt (Sigma Chemical Company, Saint Louis, Mo.) were added to 7 gms of AG50W-X8 ion exchange resin (from Bio-Rad, Richmond, Calif.) in 20 mL water and stirred overnight. Liquor was removed and lyophilized to give free acid polyglutamic acid (PGAFA). Phenylcyclidine-4-chloroformate was prepared by reacting 1.4 mg 4-hydroxyphenylcyclidine (4.24 10 -6 moles) in 0.5 mL tetrahydrofuran with 0.5 ml of 10% solution of phosgene in benzene (130 mole excess). The reaction was allowed to proceed for 2.5 hours at room temperature. Solvent was evaporated under a stream of nitrogen to yield a residue of phenylcyclidine-4-chloroformate. The residue was dissolved in 0.5 mL tetrahydrofuran and 1.7 mg of free acid poly-glutamic acid (molecular weight 40,000) in 0.5 mL 1-methyl-2-pyrolidine was added to it. The reaction was carried out overnight at room temperature then the reaction mixture was evaporated to dryness. The dried mixture was dissolved in 1.5 mL phosphate buffer, pH 7.0 and dialyzed against 0.1M sodium phosphate at ph 7.0 in a 30,00 molecular weight cut-off dialysis bag. The precipitate was filtered and dissolved in phosphate buffer. The cloudy aqueous filtrate was extracted with methylene chloride till it was clear. The aqueous layer was diluted in a buffer containing 1% fish gelatin, 25 mM Tris, 100 mM sodium chloride, 1 mm magnesium chloride, 0.1 mM zinc chloride and 0.1% sodium azide at pH 7.2 to yield 5 μgm/L phenylcyclidine-PGA capture reagent. Trigger solution: 0.3% alkaline peroxide solution in 0.25M sodium hydroxide. Samples were phenylcyclidine calibrators from a TDx™ fluorescence polarization immunoassay kit (Abbot Laboratories, North Chicago, Ill.). They contained 500, 250, 120, 60, 25, and 0 ng/mL phenylcyclidine in human urine. Procedure 50 μL of prewet solution followed by 50 μL Quat solution were dispensed on the fibrous glass pad of disposable reaction tray of the present invention. 50 μL of control or sample were pipetted into the shallow reaction wells of a disposable device of this invention using an automated pipettor. 50 μL of acridinium labeled anti-PCP antibodies were dispensed into each incubation well. The mixture was incubated for 9.8 minutes in a heated tunnel at 32° C. with the disposable device moving into the tunnel by a timing belt in steps at the rate of 0.8 inches per minute. The device would stay stationary for 36 seconds after each step for a reaction step to take place. After 9.8 minutes incubation on the moving timing belt 50 μL a solution containing PCP-PGA capture reagent was dispensed into the incubation well. The reaction mixture is further incubated for 9.8 minutes. The quaternary ammonium-polymer treated pad was rinsed with 100 μL of the IMx buffer before reaction mixture transfer. As the disposable reached under the transfer station the reaction mixture was transferred and washed from shallow incubation well onto the pre-treated porous fibrous in the read well. Transfer was affected by injecting a single pulse of 350 μL of IMx buffer into the well at a speed of 1250 μL per second from the three nozzles in the transfer device. The disposable was moved on the timing belt to allow subsequent well pairs to be located under the transfer device and to affect transfer of the reaction mixture. The disposable device was then moved to a read position, where a chemiluminescence read head (as described by a co-owned and co-pending application by Khalil et al ser. No. 16,936) was lowered to mate with the surface feature on the first two wells on the disposable to create a light-tight seal. The retained and immobilized immune complex on the pad was triggered using 0.3% alkaline peroxide solution and the signal was integrated for eight seconds. The measured signal for each well was considered to correspond to the amount of acridinium labeled conjugate attached to the fibrous pad surface by ionic forces. TABLE 4______________________________________Ion-Capture Competitive Binding Assay For Phenylcyclidine(PCP) in UrinePCP Side A Side B[ng/ml] Signal % Bound Signal % Bound______________________________________ 0 199886 0.00 181430 00.00 25 33752 83.00 27753 85.50 60 12412 94.6 12140 94.19120 6818 97.44 6106 97.54250 3223 99.28 2907 99.32500 1803 100.00 1690 10000______________________________________ The cut-off of this assay is considered at 25 ng/ml. The data indicate that Percent bound figures in Table 4 show that all controls containing 25 ng/ml PCP or higher were well differentiated from the negative control which indicates the validity of the fluid transfer and show that transfer of reaction mixture and washing of porous matrix was affected using the method and device of the present invention. Although the present invention has been described in terms of preferred embodiment, it is anticipated that various modifications and improvements will occur to those skilled in the art upon consideration of the present invention. Thus, shape, material and color of the vessel, material of the porous matrix, material and shape and number of layers of absorbant pad; Different angles of injection, shape of injectors, speed of injection, and type and composition of was solution; Treatment of fibrous pad to decrease non-specific binding can all be optimized by those skilled in the art. The device and method of this invention can be used to perform immunoassays for macromolecular antigens, viral and bacterial antigens and haptens. It can be extended to nucliec acid probes. Although the invention has been described using acridinium sulfonamide labeled tracers, it can be extended to other acridinium compounds or their analogs. Other kinds of chemiluminescence can be performed and detected using the device and method of this invention such as luminol type chemiluminescence or enzyme catalyzed dioxetane chemiluminescence. Further the device and method of this invention can be used with other detection methods and hence with other labels; thus front surface measurements using enzyme catalyzed substrate fluorescence or time resolved fluorescence and rare earth chelate labels or pripitated product immunoassays and reflectance measurements.

A disposable device suitable for performing automated solid-phase diagnostic assays which employs microparticles to complex an analyte and where the microparticle complex becomes retained and immobilized on a fibrous matrix such that the presence of analyte on the microparticles can be detached by optical means. A device is disclosed having a plurality of well pairs comprising a sample well for receiving a sample and reagents for forming a reaction mixture, a read well comprising (a) an entrance port and holder for receiving and holding a quantity of sample and assay reagents, (b) a fibrous matrix for retaining and immobilizing microparticle/analyte complexes for detection, said fibrous matrix positioned below said holder, and having an average spatial separation of fibers greater than the average diameter of said microparticles, (c) absorbent material positioned below said fibrous matrix for assisting the flow of sample and assay reagents through said fibrous matrix, (d) walls or ribs for creating a substantially light-tight real surrounding the wells, (e) a vent for venting air entrapped in the absorbent material and which is displaced by fluids absorbed therein, and (f) a passage between the sample well and the read well whereby sample and reaction mixtures can be transferred and washed from said sample well into said read well without being contacted by any apparatus.

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a gas/liquid/solids separator and more particularly to improvements in a separator designed to separate oil, carbon, and gases in the exhaust fumes of an internal combustion engine. 2. Prior Art In internal combustion engines, and especially in diesel engines, exhaust fumes containing oil, carbon, and water must be removed from the engine and disposed in an environmentally sound manner. In addition, many diesel engines run with a pressure in the crankcase to assist with the venting of potentially explosive oil vapors. These exhaust fumes must also be safely and properly handled. The container and separator apparatus must beable to deal with wide variability in the amount and content of the exhaust fumes and particularly with regard to liquids. The separator apparatus must be able to handle high liquid flows without creating high back pressure against the engine exhaust. The present invention provides several improvements over the invention disclosed in U.S. Pat. No. 4,668,254, dated May 26, 1987. In one aspect an eductor with a check valve allows exhaust fumes to enter from a pressurized crankcase. In another aspect, a swirl vanes device improves the volume and velocity changes needed to more efficiently and effectively separate liquids and solids from gases. A further aspect relates to a float ball valve assembly which allows for liquids removal at high liquid levels and provides a method to pressurize the container for rapid, forced expulsion of liquids from the container at abnormally high liquid levels. SUMMARY OF THE INVENTION In accord with the present invention there is provided an apparatus for separating gas from liquid and solid matter in the exhaust from an internal combustion engine which includes an enclosed container for liquid and solid matter having a top wall, a bottom wall, and side wall and having a first inlet for exhaust, a first outlet for liquid and a second outlet for gas; the first exhaust inlet has an exhaust passageway through the side wall and a discharge port inside the container communicates with a swirl vane device for suddenly changing the direction of and materially reducing the velocity of and increasing the path of the exhaust being discharged through such port; the first liquid outlet has a liquid passageway through the side wall with a shutoff valve in such liquid passageway; the second gas outlet has a gas passageway through the top wall; a filter means is spaced below the second gas outlet to remove entrained liquid and solid matter from the exhaust while passing therethrough with the gases passing out the second gas outlet; and means for selectively closing the gas passageway in the second gas outlet to raise the pressure of the exhaust in the container. Several aspects of the invention are provided by the swirl vanes device which includes a plurality of laterally directed swirl vanes, a base affixed to lower edges thereof for directing the exhaust laterally outwardly to cause the exhaust to change direction and increase in volume whereby its velocity is decreased and a cylindrical skirt is mounted concentrically around and spaced laterally outwardly from the swirl vanes and is suspended from a top partially overlying such swirl vanes for directing exhaust from the vanes downwardly to enhance the separation of the exhaust. The aforementioned top extends horizontally outwardly against the side wall of the container and has a plurality of spaced holes between the skirt and the side wall that allow for the free flow of exhaust upwardly therethrough with the major portion of liquids and solids remaining therebeneath. The top is affixed to the upper edges of the swirl vanes for supporting the vanes and the base within the container. A baffle is mounted below the filter means and extends in overlying position over the holes to cause substantial changes in direction of the exhaust before passing through the filter means, and such baffle includes a circumferential edge affixed to the side wall and an interior perimeter edge defining an enlarged opening extending laterally inward a sufficient distance to change the direction of the exhaust passing upwardly through the holes prior to passing into the filter means through the enlarged opening. The baffle further includes an interiorly disposed downwardly tapered portion defining the opening for increasing the flow path of exhaust from the holes. In yet other aspects, the means for selective closing of the gas passageway in the second gas outlet includes a spool valve means formed by a disk and a handle operatively connected to the disk such that when the handle is lifted vertically the disk closes the passageway. The liquid passageway includes a vertically disposed cylindrical tube communicating with the liquid outlet and the liquid collection within the container. A third outlet for liquid has a liquid passageway through the top wall with a shutoff valve on the inlet which forms a seat for the ball valve. The ball valve rises off the seat when a sufficiently high liquid level exists in the container. In other aspects of the present invention, a check valve means is used for controlling the passage of an additional second exhaust into the container, the second exhaust entering the inlet of the discharge port when the second exhaust is at a sufficiently high pressure to open the check valve means with the assistance of a low pressure created in the inlet of the discharge port by the first exhaust passing therethrough. The check valve means includes a seat, a circular disk, and biasing means connected to the disk for normally biasing the disk toward and to seat against the seat. An inlet and exhaust manifold includes valve control means for controlling the flow through the first liquid outlet and the second gas outlet. This valve control means preferably includes a spool valve having a first upper disk for selectively opening and closing the second gas passageway in the second gas outlet and a second lower disk for selectively opening and closing the first liquid passageway, the disks cooperating such that as the upper disk is operated to close the second gas passageway, the second disk opens the first liquid passageway. The valve also includes a third disk for isolating the first inlet from the second inlet and a fourth disk for isolating the liquid outlet from the first inlet. The disks are mounted in fixed relative positions on a vertical rod having an upper end portion passing through the manifold with a handle thereon. The first and second disks define a chamber within the manifold which communicates with the gas outlet when flow through the gas passageway is closed by the first disk for allowing passage of exhaust entering the chamber from the second inlet to flow through the gas outlet. Additional aspects are seen in which the check valve means is used as part of an eductor which may be located inside the container or externally as a separate assembly in some engines, two eductors may be used, one on each side of the container, having outlets forming a partitioned chamber. BRIEF DESCRIPTION OF THE DRAWINGS The novel features which are believed to be characteristic of this invention are set forth with particularity in the appended claims. The invention itself, however, both as to its organization and method of operation, together with further objects and advantages thereof, may best be understood by reference to the following description taken in connection with the accompanying drawings in which: FIG. 1 is a cross-sectional view of the improved gas, liquids, solids separator in accord with a first embodiment of the present invention; FIG. 2 is a cross-sectional view of the improved gas, liquids, solids separator in accord with a second embodiment of the present invention; FIG. 3 is a partial cross-sectional view of the improved gas, liquids, solids separator in accord with a third embodiment of the present invention; FIG. 4 is a partial cross-sectional view of the improved gas, liquids, solids separator in accord with a fourth embodiment of the present invention; FIG. 5 is a side elevational view of the separator shown in FIG. 1; FIG. 6 is a bottom view of the separator shown in FIG. 1; FIG. 7 is a top view of the separator shown in FIG. 1; FIG. 8 is an enlarged top plan view of the swirl vanes assembly used in the present invention; FIG. 9 is an enlarged cross-sectional view of the swirl vanes assembly illustrated in FIG. 8; FIG. 10 is an enlarged cross-sectional view of the eductor used in the present invention; and FIG. 11 is an enlarged cross sectional view showing the eductor assembly external of the container of the separator of FIG. 1. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT Referring now to the drawings the improved gas, liquids, and solids separator is designated generally by numeral 10 in FIG. 1. A receiving tank or container 11 has a hemispherical bottom wall 12, a cylindrical side wall 13, a hemispherical top wall 14 and an inlet and outlet manifold 15 secured adjacent the middle and top side walls 13, 14 respectively. The top wall 14 is secured to side wall 13 by way of conventional flanges 17 and bolts 16 and the bottom wall 12 is connected to sidewall 13 via similar flanges 20 and bolts 19. Preferably there are four bolt/flange fittings at the top and four bolt/flange fittings at the bottom which, in conjunction with and lower 0-rings (not shown) provide a leak-tight pressure seal. The separator 10 is designed to separate engine exhaust gases into gas, liquids, and solid components and selectively remove each component as desired. Accordingly, liquid test drain outlet 22 with isolation valve 29 is used to determine the level of water and/or oil in the container 10. Oil drain outlet 25 is used to remove oil that collects in the container 10 and will generally float on any water level present. Outlet 25 directs any oil to the appropriate waste collection apparatus. In the event of very high levels of oil and/or water in the container the overflow outlet 26 with normally open isolation valve 28 provides a path for overflowing liquids to a collection apparatus. Gas outlet 56 through top wall 14 directs gas from the exhaust to the atmosphere, or to the engine air intake, or any appropriate collection facility. A first exhaust inlet 23 receives engine exhaust from an air box and directs the exhaust into inlet chamber 30. From there the exhaust is directed into passageway 31 where it will flow into a larger chamber 34 where it undergoes a volume expansion. Chamber 34, defined by circular upper wall 42 and cylindrical side wall 43, directs the exhaust downwardly through opening 35A into swirl vanes assembly 35 comprising a series of swirl vanes 36 mounted on a lower base 37 and suspended from an upper support plate 40. Bolt 41 and nut 45 are used to secure the swirl vanes assembly 35 to upper support plate 40. Support plate 40 is affixed to the side wall 13 by welding or any other suitable manner. It is to be understood that swirl vanes 36 may be integrally cast with support plate 40 as a single unit. The swirl vanes assembly 35 is used to provide additional direction and volume changes for the gas exhaust and any entrained solids and liquids. The base 37 directs the exhaust laterally where it is directed downwardly again by cylindrical skirt 38 which is affixed to upper support plate 40. The exhaust exits skirt 38 via outlet opening 39 where it makes a U-turn which further aids in the removal of solids and liquids from the exhaust gas. Upper support plate 40 has a plurality of openings 46 located laterally the skirt 38. Gas entering the portion of the container above support plate 40 is directed into demister 47 for further removal of liquids and solids. Demister 47 is a conventional filter comprising wire mesh, crumpled metal or fibrous strands as understood in the art. Gas enters the demister 47 via opening 50 in demister baffle 48. A downwardly directed inward portion 49 of baffle 48 is located vertically above openings 46 in the support plate 40. Accordingly, the gas is more evenly directed into the demister and undergoes another directed change which further assists in removing entrained liquids. Gas exiting above demister 47 will exit through opening 56 in top wall into passageway 57 which leads to gas outlet 27. If high levels of water and/or oil exist in the container, float ball 52 will be lifted off seat 53 allowing liquids to flow through opening 54 into passageway 51 and out through overflow outlet 26. Ball cage 55 prevents ball from coming to rest other than on seat 53. If very high levels of liquid fill up the container because they enter faster than they can be removed, ball 52 may seat against opening 56. In such a case, the gas outlet 27 is closed with the result that the pressure within container 10 can increase rapidly, thereby forcing liquid out through overflow outlet 26. Normally oil is removed via oil drain outlet 25 via tubular space 65 comprised of wall 66 which is affixed to side wall 13. The lower opening 67 into space 65 is located a a sufficient distance above any level of solids that may collect against bottom wall 12. Oil exits through oil drain outlet 25 when lower spool valve body 59 having disks 63 and 63A is lifted via rod 60 and handle 64. When handle 64, sealed with packing 61, is lifted vertically by an operator, the upper gas isolation disk 58A will shut off gas outlet 27 causing a pressure increase in container 10 with the result of forcing oil out through oil drain outlet 25. The size of lower spool valve body 59 is chosen to prevent a complete closure of airbox inlet passageway 31 when the spool valve assembly 58 is operated. In many small engines, the crankcase is pressurized to assist in the venting of dangerous explosive vapors and second exhaust inlet 24 from the crankcase is used. Crankcase exhaust enters inlet chamber 32 and is directed into a passageway 33 having a check valve 69 biased normally closed against seat 72. The spring 71, and stem 73, is secured against spring base 70 in a conventional manner. The exhaust enters passageway 33 via inlet 74 from inlet chamber 32. The gas entering chamber 34 from airbox inlet passageway expands and results in a lower pressure in chamber 34 than in inlet 23. The passageways 31 and 33 with chamber 34 form an eductor assembly 68. If crankcase exhaust pressure is sufficiently high, the differential pressure across the eductor assembly 68 will cause check valve 69 to open sending crankcase exhaust through outlet 75 into chamber 34 where the separation process, as previously described, is accomplished. Isolation disk seal 63A separates airbox inlet 23 from oil drain outlet 25. Airbox inlet 23 and crankcase inlet 24 are separated by isolation disk seal 62. One method of removing liquid from the container 11 is substantially the same as that described in U.S. Pat. No. 4,668,254. Generally, this method consists of completely closing an outlet gas valve which causes pressure to increase, thus forcing liquid up the tubular space 65 and out of the container 11. In the present invention however, liquid drainage can more safely be accomplished by insuring that adequate removal of pressurized crankcase fumes from an engine is accomplished at all times during a liquid removal operation. When handle 64 is lifted by an operator to open oil outlet 25 and close upper gas outlet opening 27 some of the crankcase gases will be exhaused directly from crankcase exhaust inlet chamber 32 out through gas outlet 27 thus ensuring adequate gas removal from the engine during liquid removal. Solids are removed from the container 11 by periodically removing the bottom wall 12 and manually breaking up collected carbon and debris or by incorporating a breakup apparatus similar to that disclosed in U.S Pat. No. 4,668,254. Finally, inlet and outlet manifold 15 is secured to container walls 13 and 14 via flange 76A, which is integral to the side wall 13, and bolts 76 in a conventional manner as clearly shown in FIG. 5. The spool valve 58 may be automatically operated via level-sensing apparatus as is well understood in the art. As is well understood in the art, different engines have a different mix of gas, solids, and liquid components in the exhaust. Accordingly, the separator 10 can be modified for specific engines and/or applications. In FIG. 2, a second embodiment of the present invention is illustrated for use with 4-cycle engines. In this embodiment, manifold 15 may be omitted and crankcase exhaust enters directly into chamber 34 via passageway 31 and flows through swirl vanes assembly 35. The airbox inlet 23 can be used as an inlet and no valves are used either at the crankcase inlet 23 or at the gas outlet opening 56 where gas exhaust is directed via outlet 56A to the air intake of the engine. Oil and water is periodically drained manually via valve 77 on drain outlet 22. The operation of this second embodiment is as otherwise described above and basically the gas exhaust is directed through swirl vanes 36 and down and around skirt 38 into and through demister 47 via openings 46 in support plate 40. The eductor assembly 68 and the over flow assembly of float ball 52 are not needed and therefore are omitted. In FIG. 3, a third embodiment of the present invention is illustrated for use in 2-cycle diesel engines. Bottom wall 12 of the container of FIGS. 1 and 3 is removed and the remainder of the container is mounted onto an enlarged lower portion of the separator substantially as disclosed in U.S Pat. No. 4,668,254 which has greater liquid capacity. Airbox exhaust, controlled by valve 86, enters passageway 31 where it is directed through the swirl vanes assembly 35 and through demister 47 as described above. Gas exhausts via opening 56 through valve 78. The spool valve 58 may also be used to control exhaust entry and gas flow output if so desired in a given application. Flange 79 is integral with sidewall 13 for fitting the container 11 onto bottom 80 and securing it thereto via hold-down lugs 81 and bolts 82 in a conventional manner. Oil is removed by closing valve 78, pressurizing container 12 and forcing the oil out via drain tube 83 upon opening of a manually operated isolation valve 84. Pressure relef valve 85 operates to prevent excessive pressure build-up in the container 11. In FIG. 4, a fourth embodiment of the present invention is illustrated for use with a 2-cycle "V" block engine. Container 11 has two identical eductors 68 and 68'. Two crankcase inlets 24 and 24' are used with two airbox inlets 23 and 23'. Divider 41A is a plate extending across the opening 35A into swirl vanes assembly 35, thus separating the inlet chambers 34 and 34'. The divider 41A inhibits the passage of the exhaust from one inlet chamber from affecting the inlet flow from the other exhausts. Divider 41A is secured into place by bolt 41 and nut 45 or it may be cast as an integral part of support plate 40. The additional inlets 23' and 24' be controlled via separate valves (not shown) or a modified version of manifold 15. Gas outlet 27 is sufficiently large to handle the entire output from such "V" block engines. Valve 87 on outlet 22 is used to test for the presence of water and/or oil in the container 11 and/or to remove same from the container in the event pressurized withdrawal via 88 and 25 was not desired. Oil normally is removed via oil drain tube 88 which is threaded or welded into boss 89. Boss 89 may be integral with support plate 40 and/or with side wall 13, and has an outlet 88A communicating with oil outlet 25, as clearly shown in FIG. 4. The overflow control system shown in FIG. 1 comprising ball 52, passageway 51 and outlet 26 and valve 28 may be used in the third and fourth embodiments as may be required in a given application. Without departing from the invention, the eductor assembly 68 can be physically located outside the container 11, as illustrated in FIG. 1. External eductor assembly 90 is comprised of a small tube 91 (from airbox exhaust) having a passageway 92 therethrough, tube 91 communicates within passageway 93 formed by an extension tube 94 fitted to airbox inlet 23. Airbox exhaust enters passageway 92 via opening 95 and exits into passageway 93 from outlet 96. The exhaust will then expand due to the greater volume of passageway 93 as compared to the volume of passageway 92 and result in a lower pressure therein. Check valve 97 is located within passageway 98 and controls crankcase exhaust flow in response to the differential pressure between crankcase exhaust pressure inlet 98A and the pressure within passageway 93, which is the same pressure at valve outlet 98B. If the differential pressure is sufficiently high, valve 97 opens and allows passage of crankcase exhaust from inlet 98A to valve outlet 98B and into the container 11 via passageway 31. The relative size of the passageways 31, 92 and 93 are chosen for a particular application. Sleeve 99, packing 100, and packig nut 101 provide a pressure seal around tube 91. Check valve 97 is a conventional device having seat 102 and spring 103 which provides a closing bias on valve 97 and thus establishes the differential pressure required to open the valve 97. Spring 103 is secured to rigidly mounted spring base 105 which provides passage for pin-shaped valve stem 104 therethrough as understood in the art. While the invention has been described with respect to certain specific embodiments, it will be appreciated that many modifications and changes may be made by those skilled in the art without departing from the spirit of the invention. It is intended, therefore by the appended claims to cover all such modifications and changes as fall within the true spirit and scope of the invention.

The apparatus includes a swirl vanes device for reducing the velocity of exhaust fumes fed into an enclosed container with the accompanying direction and volume changes enhancing the separation of the exhaust into gas, liquid, and solid components. Solids and liquids collect in the container and gas passes out through a demister filter. With engines having a pressurized crankcase exhaust and an air box outlet, an eductor assembly employing a spring-biased check valve is used to control the entrance of crankcase exhaust into an inlet chamber having a low pressure created by the volume expansion of inlet air box exhaust. A liquid overflow system has a floatable ball valve to remove liquid from the container under conditions of high liquid levels. An inlet and outlet manifold houses a spool valve for the selective control and isolation of the inlet and outlet openings of the container so that the container may be pressurized to remove the liquid collected therein. For some "V"-Block engines a pair of oppositively disposed air box and pressurized crankcase inlets are used each having an eductor assembly for control of crankcase exhaust flow into the container and into a partitioned inlet chamber to provide effective isolation therebetween.

CROSS-REFERENCE TO RELATED APPLICATIONS This application is a National Stage application under 35 U.S.C. §371 of PCT Application No. PCT/GB2007/001362, filed Apr. 13, 2007, entitled “METHOD OF ION ABUNDANCE AUGMENTATION IN A MASS SPECTROMETER”, which claims the priority benefit of GB Application No. 0607542.8, filed Apr. 13, 2006, entitled “MASS SPECTROMETER WITH ION STORAGE DEVICE”, which applications are incorporated herein by reference in their entireties. FIELD OF THE INVENTION The present invention relates to a mass spectrometer and a method of mass spectrometry, in particular for performing MS n experiments. BACKGROUND TO THE INVENTION Tandem mass spectrometry is a well known technique by which trace analysis and structural elucidation of samples may be carried out. In a first step, parent ions are mass analysed/filtered to select ions of a mass to change ratio of interest, and in a second step these ions are fragmented by, for example, collision with a gas such as argon. The resultant fragment ions are then mass analysed usually by producing a mass spectrum. Various arrangements for carrying out multiple stage mass analysis or MS n have been proposed or are commercially available, such as the triple quadrupole mass spectrometer and the hybrid quadrupole/time-of-flight mass spectrometer. In the triple quadrupole, a first quadrupole Q 1 acts as a first stage of mass analysis by filtering out ions outside of a chosen mass-to-charge ratio range. A second quadrupole Q 2 is typically arranged as a quadrupole ion guide arranged in a gas collision cell. The fragment ions that result from the collisions in Q 2 are then mass analysed by the third quadrupole Q 3 downstream of Q 2 . In the hybrid arrangement, the second analysing quadrupole Q 3 may be replaced by a time-of-flight (TOF) mass spectrometer. In each case, separate analysers are employed before and after the collision cell. In GB-A-2,400,724, various arrangements are described wherein a single mass filter/analyser is employed to carry out filtering and analysis in both directions. In particular, an ion detector is positioned upstream of the mass filter/analyser, and ions pass through the mass filter/analyser to be stored in a downstream ion trap. The ions are then ejected from the downstream trap back through the mass filter/analyser before being detected by the upstream ion detector. Various fragmentation procedures, still employing a single mass filter/analyser, are also described, which permit MS/MS experiments to be carried out. Similar arrangements are also shown in WO-A-2004/001878 (Verentchikov et al). Ions are passed from a source to a TOF analyser, which acts as an ion selector, from where ions are ejected to a fragmentation cell. From here, they pass back through the TOF analyser and are detected. For MS n , the fragment ions can be recycled through the spectrometer. US-A-2004/0245455 (Reinhold) carries out a similar procedure for MS n but employs a high sensitivity linear trap rather than a TOF analyser to carry out the ion selection. JP-A-2001-143654 relates to an ion trap, ejecting ions on a circular orbit for mass separation followed by detection. The present invention seeks against this background to provide an improved method and apparatus for MS n . SUMMARY OF THE INVENTION According to a first aspect of the present invention there is provided a method of improving the detection limits of a mass spectrometer comprising: (a) generating sample ions from an ion source; (b) storing the sample ions in a first ion storage device; (c) ejecting the stored ions into an ion selection device; (d) selecting and ejecting ions of a chosen mass to charge ratio out of the ion selection device; (e) storing the ions ejected from the ion selection device in a second ion storage device without passing them back through the ion selection device; (f) repeating the preceding steps (a) to (e) so as to augment the ions of the said chosen mass to charge ratio stored in the second ion storage device; and (g) transferring the augmented ions of the said chosen mass to charge ratio back to the first ion storage device for subsequent analysis. This cycle may be repeated, optionally, multiple times, so as to allow MS n . The present invention thus employs a cyclical arrangement in which ions are trapped, optionally cooled, and ejected from an exit aperture. A subset of these ions are returned to the ion storage device. This cyclical arrangement provides a number of advantages over the art identified in the introduction above, which instead employs a “back and forth” procedure via the same aperture in the ion trap. Firstly, the number of devices required to store and inject ions into the ion selector is minimised (and in the preferred embodiment is just one). Modern storage and injection devices that permit very high mass resolution and dynamic range are expensive to produce and demanding to control so that the arrangement of the present invention represents a significant cost and control saving over the art. Secondly, by using the same (first) ion storage device to inject into, and receive ions back from, an external ion selection device, the number of MS stages is reduced. This in turn improves ion transport efficiency which depends upon the number of MS stages. Typically, ions ejected from an external ion selector will have very different characteristics to those of the ions ejected from the ion storage device. By loading ions into the ion storage device through a dedicated ion inlet port (a first ion transport aperture), particularly when arriving back at the ion storage device from an external fragmentation device, this process can be carried out in a well controlled manner. This minimises ion losses which in turn improves the ion transport efficiency of the apparatus. This technique also allows the detection limit of the instrument to be improved, where the ions of the chosen mass to charge ratio are of low abundance in the sample. Once a sufficient quantity of these low abundance precursor ions have been built up in the second ion storage device, they can be injected back to the first ion storage device for capture there (bypassing the ion selection device) and subsequent MS n analysis, for example. Although preferably the ions leave the first ion storage device through a first ion transport aperture and are received back into it via a second separate ion transport aperture, this is not essential in this aspect of the invention and ejection and capture through the same aperture are feasible. Optionally, at the same time as the low abundance precursor ions are being moved to the second ion storage device to improve total population of these particular precursor ions, the ion selection device may continue to retain and further refine the selection of other desired precursor ions. When sufficiently narrowly selected, these precursor ions can be ejected from the ion selection device and fragmented in a fragmentation device to produce fragment ions. These fragment ions may then be transferred to the first ion storage device, and MS n of these fragment ions may then be carried out or they may likewise be stored in the second ion storage device so that subsequent cycles may further enrich the number of ions stored in this way to again increase the detection limit of the instrument for that particular fragment ion. In a second aspect, the present invention may reside in a method of improving the detection limits of a mass spectrometer comprising: (a) generating sample ions from an ion source; (b) storing the sample ions in a first ion storage device; (c) ejecting the stored ions into an ion selection device; (d) selecting and ejecting ions of analytical interest out of the ion selection device; (e) fragmenting the ions ejected from the ion selection device in a fragmentation device; (f) storing fragment ions in a second ion storage device without passing them back through the ion selection device; (g) repeating the preceding steps (a) to (f) so as to augment the fragment ions stored in the second ion storage device, and (h) transferring the augmented fragment ions back to the first ion storage device for subsequent analysis. As above, ion ejection from the first ion storage device and ion capture back there may be through separate ion transport apertures or through the same one. Ions in the first ion storage device may be mass-analysed either in a separate mass analyser, such as an Orbitrap as described in the above-referenced U.S. Pat. No. 5,886,346, or may instead be injected back into the ion selection device for mass analysis there. An ion source may be provided to supply a continuous or pulsed stream of sample ions to the ion storage device. In one preferred arrangement, the optional fragmentation device may be located between such an ion source and the ion storage device instead. In either case, complicated MS n experiments may be carried out in parallel by allowing division of (and, optionally, separate analysis of) sub populations of ions, either directly from the ion source or deriving from previous cycles of MS. This in turn results in an increase in the duty cycle of the instrument and can likewise improve the detection limits of it as well. Although preferred embodiments of the invention may employ any ion selection device, it is particularly suited to and beneficial in combination with an electrostatic trap (EST). In recent years, mass spectrometers including electrostatic traps (ESTs) have started to become commercially available. Relative to quadrupole mass analysers/filters, ESTs have a much higher mass accuracy (parts per million, potentially), and relative to quadrupole-orthogonal acceleration TOF instruments, they have a much superior duty cycle and dynamic range. Within the framework of this application, an EST is considered as a general class of ion optical devices wherein moving ions change their direction of movement at least along one direction multiple times in substantially electrostatic fields. If these multiple reflections are confined within a limited volume so that ion trajectories are winding over themselves, then the resultant EST is known as a “closed” type. Examples of this “closed” type of mass spectrometer may be found in U.S. Pat. No. 3,226,543, DE-A-04408489, and U.S. Pat. No. 5,886,346. Alternatively, ions could combine multiple changes in one direction with a shift along another direction so that the ion trajectories do not wind on themselves. Such ESTs are typically referred to as of the “open” type and examples may be found in GB-A-2,080,021, SU-A-1,716,922, SU-A-1,725,289, WO-A-2005/001878, and US-A-20050103992 FIG. 2. Of the electrostatic traps, some, such as those described in U.S. Pat. No. 6,300,625, US-A-2005/0,103,992 and WO-A-2005/001878 are filled from an external ion source and eject ions to an external detector downstream of the EST. Others, such as the Orbitrap as described in U.S. Pat. No. 5,886,346, employ techniques such as image current detection to detect ions within the trap without ejection. Electrostatic traps may be used for precise mass selection of externally injected ions (as described, for example, in U.S. Pat. Nos. 6,872,938 and 6,013,913). Here, precursor ions are selected by applying AC voltages in resonance with ion oscillations in the EST. Moreover, fragmentation within the EST is achieved through the introduction of a collision gas, laser pulses or otherwise, and subsequent excitation steps are necessary to achieve detection of the resultant fragments (in the case of the arrangements of U.S. Pat. Nos. 6,872,938 and 6,013,913, this is done through image current detection). Electrostatic traps are not, however, without difficulties. For example, ESTs typically have demanding ion injection requirements. For example, our earlier patent applications number WO-A-02/078046 and WO05124821A2 describe the use of a linear trap (LT) to achieve the combination of criteria required to ensure that highly coherent packets are injected into an EST device. The need to produce very short time duration ion packets (each of which contains large numbers of ions) for such high performance, high mass resolution devices means that the direction of optimum ion extraction in such ion injection devices is typically different from the direction of efficient ion capture. Secondly, advanced ESTs tend to have stringent vacuum requirements to avoid ion losses, whereas the ion traps and fragmentors to which they may interface are typically gas filled so that there is typically at least 5 orders of magnitude pressure differential between such devices and the EST. To avoid fragmentation during ion extraction, it is necessary to minimise the product of pressure by gas thickness (typically, to keep it below 10 −3 . . . 10 −2 mm*torr), while for efficient ion trapping this product needs to be maximised (typically, to exceed 0.2 . . . 0.5 mm*torr) Where the ion selection device is an EST, therefore, in a preferred embodiment of the present invention, the use of an ion storage device with different ion inlet and exit ports permits the same ion storage device to provide ions in an appropriate manner for injection into the EST, but nevertheless to allow the stream or long pulses of ions coming back from the EST via the fragmentation device to be loaded back into that first ion storage device in a well controlled manner, through the second or in certain embodiments, the third ion transport aperture. Any form of electrostatic trap may be used, if this is what constitutes the ion selection device. A particularly preferred arrangement involves an EST in which the ion beam cross-section remains limited due to the focusing effect of the electrodes of the EST, as this improves efficiency of the subsequent ion ejection from the EST. Either an open or a closed type EST could be used. Multiple reflections allow for increasing separation between ions of different mass-to-charge ratios, so that a specific mass-to-charge ratio of interest may, optionally, be selected, or simply a narrower range of mass-to-charge ratios than was injected into the ion selection device. Selection could be done by deflecting unwanted ions using electric pulses applied to dedicated electrodes, preferably located in the plane of time-of-flight focus of ion mirrors. In the case of closed EST, a multitude of deflection pulses might be required to provide progressively narrowing m/z ranges of selection. It is possible to use the fragmentation device in two modes: in a first mode, precursor ions can be fragmented in the fragmentation device in the usual manner, and in a second mode, by controlling the ion energy, precursor ions can pass through the fragmentation device without fragmentation. This allows both MS n and ion abundance improvement, together or separately: once ions have been injected from the first ion storage device into the ion selection device, specific low abundance precursor ions can be ejected controllably from the ion selection device and be stored back in the first ion storage device, without having been fragmented in the fragmentation device. This may be achieved by passing these low abundance precursor ions through the fragmentation device at energies insufficient to cause fragmentation. Energy spread could be reduced for a given m/z by employing pulsed deceleration fields (e.g. formed in a gap between two flat electrodes with apertures). When ions enter a decelerating electric field on the way back from the mass selector to the first ion storage device, higher energy ions overtake lower energy ions and thus move to a greater depth in the deceleration field. After all the ions of this particular m/z enter the deceleration field, the field is switched off. Therefore ions with initially higher energy experience a higher drop in potential relatively to ground potential than the lower energy ions, thus making their energies equal. By matching the potential drop to the energy spread upon exit from the mass selector, a significant reduction of the energy spread may be achieved. Fragmentation of ions may thereby be avoided, or, alternatively, control over the fragmentation may be improved. In accordance with a further aspect of the present invention, there is provided a mass spectrometer comprising an ion storage device arranged to store ions, an ion selection device and a fragmentation/storage device. The ion selection device is arranged to receive ions stored in the first ion storage device and ejected therefrom, and to select a subset of ions from those received. The second fragmentation/storage device is arranged to receive at least some of the ions selected by the ion selection device. The second fragmentation/storage device is then configured, in use, to direct ions received from the ion selection device, or their products, back to the first ion storage device without passing them back through the ion selection device. The present invention may also be found in a method of mass spectrometry comprising the steps of, in a first cycle, storing sample ions in a first ion storage device, the first ion storage device having an exit aperture and a spatially separate ion transport aperture; ejecting the stored ions out of the exit aperture into a separate ion selection device; receiving at least some of the ions ejected from the first ion storage device, or their derivatives, back through the ion transport aperture of the first ion storage device; and storing the received ions in the first ion storage device. In accordance with a yet further aspect of the present invention, there is provided a method of mass spectrometry comprising storing ions in a first ion storage device; ejecting ions from the first ion storage device to an ion selection device; selecting a subset of ions within the ion selection device; ejecting the ions from the ion selection device; capturing at least some of the selected ions in one of a fragmentation device or second ion storage device; and returning at least some of the ions captured in the said one of the fragmentation device or second ion storage device respectively, or their products, to the first ion storage device along a return ion path that bypasses the ion selection device. In accordance with still another aspect of the present invention there is provided a method of mass spectrometry comprising accumulating ions in an ion trap, injecting the accumulated ions into an ion selection device, selecting and ejecting a subset of the ions in the ion selection device, and storing the ejected subset of the ions directly back in the ion trap without intermediate ion storage. Other preferred embodiments and advantages of the present invention will become apparent from the following description of a preferred embodiment. BRIEF DESCRIPTION OF THE DRAWINGS The present invention may be put into practice in a number of ways and one preferred embodiment will now be described by way of example only and with reference to the accompanying drawings in which: FIG. 1 shows, in block diagram form, an overview of a mass spectrometer embodying the present invention; FIG. 2 shows a preferred implementation of the mass spectrometer of FIG. 1 , including an electrostatic trap and a separate fragmentation cell; FIG. 3 shows a schematic representation of one particularly suitable arrangement of an electrostatic trap for use with the mass spectrometer of FIG. 2 ; FIG. 4 shows a first alternative arrangement of a mass spectrometer embodying the present invention; FIG. 5 shows a second alternative arrangement of a mass spectrometer embodying the present invention; FIG. 6 shows a third alternative arrangement of a mass spectrometer embodying the present invention; FIG. 7 shows a fourth alternative arrangement of a mass spectrometer embodying the present invention; FIG. 8 shows a fifth alternative arrangement of a mass spectrometer embodying the present invention; FIG. 9 shows an ion mirror arrangement for increasing energy dispersion of ions prior to injection into the fragmentation cell of FIGS. 1 , 2 , and 4 - 8 ; FIG. 10 shows a first embodiment of an ion deceleration arrangement for reducing energy spread prior to injection of ions into the fragmentation cell of FIGS. 1 , 2 , and 4 - 8 ; FIG. 11 shows a second embodiment of an ion deceleration arrangement for reducing energy spread prior to injection of ions into the fragmentation cell of FIGS. 1 , 2 , and 4 - 8 ; FIG. 12 shows a plot of energy spread of ions as a function of the switching time of a voltage applied to the ion deceleration arrangement of FIGS. 10 and 11 ; and FIG. 13 shows a plot of spatial spread of ions as a function of the switching time of a voltage applied to the ion deceleration arrangement of FIGS. 10 and 11 . DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS Referring first to FIG. 1 , a mass spectrometer 10 is shown in block diagram format. The mass spectrometer 10 comprises an ion source 20 for generating ions to be mass analysed. The ions from the ion source 20 are admitted into an ion trap 30 which may, for example, be a gas-filled RF multipole or a curved quadrupole as is described, for example, in WO-A-05124821. The ions are stored in the ion trap 30 , and collisional cooling of the ions may take place as is described for example in our co-pending application number GB0506287.2, the contents of which are incorporated herein by reference. Ions stored in the ion trap 30 may then be pulse-ejected towards an ion selection device which is preferably an electrostatic trap 40 . Pulsed ejection produces narrow ion packets. These are captured in the electrostatic trap 40 and experience multiple reflections therein in a manner to be described in connection particularly with FIG. 3 below. On each reflection, or after a certain number of reflections, unwanted ions are pulse-deflected out of the electrostatic trap 40 , for example to a detector 75 or to a fragmentation cell 50 . Preferably, the ion detector 75 is located close to the plane of time-of-flight focus of the ion mirrors, where the duration of the ion packets is at a minimum. Thus, only ions of analytical interest are left in the electrostatic trap 40 . Further reflections will continue to increase the separation between adjacent masses, so that further narrowing of the selection window may be achieved. Ultimately, all ions having a mass-to-charge ratio adjacent to the mass-to-charge ratio m/z of interest are eliminated. After the selection process is completed, ions are transferred out of the electrostatic trap 40 into the fragmentation cell 50 which is external to the electrostatic trap 40 . Ions of analytical interest that remain in the electrostatic trap 40 at the end of the selection procedure are ejected with sufficient energy to allow them to fragment within the fragmentation cell 50 . Following fragmentation in the fragmentation cell, ion fragments are transferred back into the ion trap 30 . Here they are stored, so that, in a further cycle, a next stage of MS may be carried out. In this manner, MS/MS or, indeed, MS n may be achieved. An alternative or additional feature of the arrangement of FIG. 1 is that ions ejected from the electrostatic trap (because they are outside the selection window) may be passed through the fragmentation cell 50 without fragmentation. Typically, this could be achieved by decelerating such ions at relatively low energies so that they do not have sufficient energy to fragment in the fragmentation cell. These unfragmented ions which are outside of the selection window of immediate interest in a given cycle can be transferred onwards from the collision cell 50 to a auxiliary ion storage device 60 . In subsequent cycles (for example, when further mass spectrometric analysis of the fragment ions as described above has been completed), the ions rejected from the electrostatic trap 40 in the first instance (because they are outside of the selection window of previous interest) can be transferred from the auxiliary ion storage device 60 to the ion trap 30 for separate analysis. Moreover the auxiliary ion storage device 60 can be used to increase the number of ions of a particular mass to charge ratio, particularly when these ions have a relatively low abundance in the sample to be analysed. This is achieved by using the fragmentation device in non-fragmentation mode and setting the electrostatic trap to pass only ions of particular mass to charge ratio that is of interest but which is of limited abundance. These ions are stored in the auxiliary ion storage device 60 but are augmented by additional ions of that same chosen mass to charge ratio selected and ejected from the electrostatic trap 40 using similar criteria in subsequent cycles. Ions of multiple m/z ratios could be stored together as well, e.g. by using several ejections from the trap 40 with different m/z. Of course, either the previously unwanted precursor ions, or the precursor ions that are of interest but which have a low abundance in the sample and thus first need to be increased in number, can be the subject of subsequent fragmentation for MS n . In that case, the auxiliary ion storage device 60 could first eject its contents into the fragmentation cell 50 , rather than transferring its contents directly back to the ion trap 30 . Mass analysis of ions can take place at various locations and in various ways. For example, ions stored in the ion trap may be mass-analysed in the electrostatic trap 40 (more details of which are set out below in connection with FIG. 2 ). Additionally or alternatively, a separate mass analyser 70 may be provided in communication with the ion trap 30 . Turning now to FIG. 2 , a preferred embodiment of a mass spectrometer 10 is shown in more detail. The ion source 20 shown in FIG. 2 is a pulsed laser source (preferably a matrix-assisted laser desorption ionization (MALDI) source in which ions are generated through irradiation from a pulsed laser source 22 ). Nevertheless, a continuous ion source, such as an atmospheric pressure electrospray source, could equally be employed. Between the ion trap 30 and the ion source 20 is a pre-trap 24 which may, for example, be a segmented RF-only gas-filled multipole. Once the pre-trap is filled, ions in it are transferred into the ion trap 30 , which in the preferred embodiment is a gas-filled RF-only linear quadrupole, via a lens arrangement 26 . The ions are stored in the ion trap 30 until the RF is switched off and a DC voltage is applied across the rods. This technique is set out in detail in our co-pending applications, published as GB-A-2,415,541 and WO-A-2005/124821, the details of which are incorporated herein in their entirety. The applied voltage gradient accelerates ions through ion optics 32 which may, optionally, include a grid or electrode 34 arranged to sense charge. The charge-sensing grid 34 permits estimation of the number of ions. It is desirable to have an estimate of the number of ions since, if there are too many ions, the resulting mass shifts become difficult to compensate. Thus, if the ion number exceeds a predefined limit (as estimated using the grid 34 ), all ions may be discarded and an accumulation of ions in the pre-trap 24 may be repeated, with a proportionally lowered number of pulses from the pulsed laser 22 , and/or a proportionally shorter duration of accumulation. Other techniques for controlling the number of trapped ions could be employed, such as are described in U.S. Pat. No. 5,572,022, for example. After acceleration through the ion optics 32 the ions are focused into short packets between 10 and 100 ns long for each m/z and enter the mass selector 40 . Various forms of ion selection device may be employed, as will become apparent from the following. If the ion selection device is an electrostatic trap, for example, the specific details of that are not critical to the invention. For example, the electrostatic trap, if employed, may be open or closed, with two or more ion mirrors or electric sectors, and with or without orbiting. At present, a simple and preferred arrangement of an electrostatic trap embodying the ion selection device 40 is shown in FIG. 3 . This simple arrangement comprises two electrostatic mirrors 42 , 44 and two modulators 46 , 48 that either keep ions on a recurring path or deflect them outside of this path. The mirrors may be formed of either a circular or a parallel plate. As the voltages on the mirrors are static, they may be sustained with very high accuracy, which is favourable for stability and mass accuracy within the electrostatic trap 40 . The modulators 46 , 48 are typically a compact pair of openings with pulsed or static voltages applied across them, normally with guard plates on both sides to control fringing fields. Voltage pulses with rise and fall times of less than 10-100 ns (measured between 10% and 90% of peak) and amplitudes up to a few hundred volts are preferable for high-resolution selection of precursor ions. Preferably, both modulators 46 and 48 are located in the planes of time-of-flight focusing of the corresponding mirrors 42 , 44 which, in turn, may preferably but do not necessarily coincide with the centre of the electrostatic trap 40 . Typically, ions are detected through image current detection (which is in itself a well known technique and is not therefore described further). Returning again to FIG. 2 , after a sufficient number of reflections and voltage pulses within the electrostatic trap 40 , only a narrow mass range of interest is left in the electrostatic trap 40 , thus completing precursor ion selection. Selected ions in the EST 40 are then deflected on a path that is different from their input path and which leads to the fragmentation cell 50 , or alternatively the ions may pass to detector 75 . Preferably, this diversion to the fragmentation cell is performed through a deceleration lens 80 which is described in further detail in connection with FIGS. 9 to 13 below. The ultimate energy of the collisions within the fragmentation cell 50 may be adjusted by appropriate biasing of the DC offset on the fragmentation cell 50 . Preferably, the fragmentation cell 50 is a segmented RF-only multipole with axial DC field created along its segments. With appropriate gas density in the fragmentation cell (detailed below) and energy (which is typically between 30 and 50 V/kDa), ion fragments are transported through the cell towards the ion trap 30 again. Alternatively or concurrently, ions could be trapped within the fragmentation cell 50 and then be fragmented using other types of fragmentation such as electron transfer dissociation (ETD), electron capture dissociation (ECD), surface-induced dissociation (SID), photo-induced dissociation (PID), and so forth. Once the ions have been stored in the ion trap 30 again, they are ready for onward transmission towards the electrostatic trap 40 for a further stage of MS n , or towards the electrostatic trap 40 for mass analysis there, or alternatively towards the mass analyser 70 which may be a time-of-flight (TOF) mass spectrometer or an RF ion trap or FT ICR or, as shown in FIG. 2 , an Orbitrap mass spectrometer. Preferably, the mass analyser 70 has its own automatic gain control (AGC) facilities, to limit or regulate space charge. In the embodiment of FIG. 2 , this is carried out through an electrometer grid 90 on the entrance to the Orbitrap 70 . An optional detector 75 may be placed on one of the exit paths from the electrostatic trap 40 . This may be used for a multitude of purposes. For example, the detector may be employed for accurate control of the number of ions during a pre-scan (that is, automatic gain control), with ions arriving directly from the ion trap 30 . Additionally or alternatively, those ions outside of the mass window of interest (in other words, unwanted ions from the ion source, at least in that cycle of the mass analysis) may be detected using the detector. As a further alternative, the selected mass range in the electrostatic 40 may be detected with high resolution, following multiple reflections in the EST as described above. Still a further modification may involve the detection of heavy singly-charged molecules, such as proteins, polymers and DNAs with appropriate post-acceleration stages. By way of example only, the detector may be an electron multiplier or a microchannel/microsphere plate which has single ion sensitivity and can be used for detection of weak signals. Alternatively, the detector may be a collector and can thus measure very strong signals (potentially more than 10 4 ions in a peak). More than one detector could be employed, with modulators directing ion packets towards one or another according to spectral information obtained, for example, from the previous acquisition cycle. FIG. 4 illustrates an arrangement which is essentially similar to the arrangement of FIG. 2 though with some specific differences. As such, like reference numerals denote parts common to the arrangements of FIGS. 2 and 4 . The arrangement of FIG. 4 again comprises an ion source 20 which supplies ions to a pre-trap which in the embodiment of FIG. 4 is a auxiliary ion storage device 60 . Downstream of that pre-trap/auxiliary ion storage device 60 is a ion trap 30 (which in the preferred embodiment is a curved trap) and a fragmentation cell 50 . In contrast to the arrangement of FIG. 2 , however, the arrangement of FIG. 4 locates the fragmentation cell between the ion trap 30 and the auxiliary ion storage device 60 , that is, on the “source” side of the ion trap, rather than between the ion trap and the electrostatic trap as it is located in FIG. 2 . In use, ions are built up in the ion trap 30 and then orthogonally ejected from it through ion optics 32 to an electrostatic trap 40 . A first modulator/deflector 100 downstream of the ion optics 32 directs the ions from the ion trap 30 into the EST 40 . Ions are reflected along the axis of the EST 40 and, following ion selection there, they are ejected back to the ion trap 30 . To assist with ion guiding in that process, an optional electric sector (such as a toroidal or cylindrical capacitor) 110 may be employed. A deceleration lens is located between the electric sector 110 and the return path into the ion trap 30 . Deceleration may involve pulsed electric fields as described above. Due to the low pressure in the ion trap 30 , ions arriving back at that trap 30 fly through it and fragment in the fragmentation cell 50 which is located between that ion trap 30 and the auxiliary ion storage device 60 (i.e. on the ion source side of the ion trap 30 ). The fragments are then trapped in the ion trap 30 . As with FIG. 2 , an Orbitrap mass analyser 70 is employed to allow accurate mass analysis of ions ejected from the ion trap 30 at any chosen stage of MS n . The mass analyser 70 is located downstream of the ion trap (i.e. on the same side of the ion trap as the EST 40 ) and a second deflector 120 “gates” ions either to the EST 40 via the first deflector 100 or into the mass analyser 70 . Other components shown in FIG. 4 are RF only transport multipoles that act as interfaces between the various stages of the arrangement as will be well understood by those skilled in the art. Between the ion trap 30 and the fragmentation cell 50 may also be located an ion deceleration arrangement (see FIGS. 9-13 below). FIG. 5 shows a further alternative arrangement to that shown in FIG. 2 and FIG. 4 and like components are once again labelled with like reference numerals. The arrangement of FIG. 5 is similar to that of FIG. 2 in that ions are generated by an ion source 20 and then pass through (or bypass) a pre-trap and auxiliary ion storage device 60 before being stored in a ion trap 30 . Ions are orthogonally ejected from the ion trap 30 , through ion optics 32 , and are deflected by a first modulator/deflector 100 onto the axis of an EST 40 , as with FIG. 4 . In contrast to FIG. 4 , however, as an alternative to ion selection in the EST 40 , ions may instead be deflected by modulator/deflector 100 into an electric sector 110 and from there into a fragmentation cell 50 via an ion deceleration arrangement 80 . Thus (in contrast to FIG. 4 ) the fragmentation cell 50 is not on the source side of the ion trap 30 . Following ejection from the fragmentation cell 50 , ions pass through a curved transport multipole 130 and then a linear RF only transport multipole 140 back into the ion trap 30 . An Orbitrap or other mass analyser 70 is again provided to permit accurate mass analysis at any stage of MS n . FIG. 6 shows still a further alternative arrangement which is essentially identical in concept to the arrangement of FIG. 2 , except that the EST 40 is not of the “closed” type trap illustrated in FIG. 3 , but is instead of the open type as is described in the documents set out in the introduction above. More specifically, the mass spectrometer of FIG. 6 comprises an ion source 20 which provides a supply of ions to a pre-trap/auxiliary ion store 60 (further ion optics is also shown but is not labelled in FIG. 6 ). Downstream of the pre-trap/auxiliary ion storage device 60 is a further ion storage device which in the arrangement of FIG. 6 is once again a curved ion trap 30 . Ions are ejected from the curved trap 30 in an orthogonal direction, through ion optics 32 , towards an EST 40 ′ where the ions undergo multiple reflections. A modulator/deflector 100 ′ is located towards the “exit” of the EST 40 ′ and this permits ions to be deflected either into a detector 150 or to a fragmentation cell 50 via an electric sector 110 and an ion decelerator arrangement 80 . From here, ions may be injected back into the ion trap 30 once more, again through an entrance aperture which is distinct from the exit aperture through which ions pass on their way to the EST 40 ′. The arrangement of FIG. 6 also includes associated ion optics but this is not shown for the sake of clarity in that Figure. In one alternative, the EST 40 ′ of FIG. 6 may employ parallel mirrors (see, for example, WO-A-2005/001878) or elongate electric sectors (see, for example, US-A-2005/0103992). More complex shapes of trajectories or EST ion optics could be used. FIG. 7 shows still a further embodiment of a mass spectrometer in accordance with aspects of the present invention. As with FIG. 4 , the spectrometer comprises an ion source 20 which supplies ions to a pre-trap which, as in the embodiment of FIG. 4 , is a auxiliary ion storage device 60 . Downstream of that pre-trap/auxiliary ion storage device 60 is a ion trap 30 (which in the preferred embodiment is a curved trap) and a fragmentation cell 50 . The fragmentation cell 50 could be located on either side of the ion trap 30 though in the embodiment of FIG. 7 the fragmentation cell 50 is shown between the ion source 20 and the ion trap 30 . As with the previous embodiments, an ion deceleration arrangement 80 is located in preference between the ion trap 30 and the fragmentation cell 50 . In use, ions enter the ion trap 30 via an ion entrance aperture 28 and are accumulated in the ion trap 30 . They are then orthogonally ejected through an exit aperture 29 which is separate from the entrance aperture 28 , to an electrostatic trap 40 . In the arrangement shown in FIG. 7 , the exit aperture is elongate in a direction generally perpendicular to the direction of ion ejection (i.e., the exit aperture 29 is slot-like). The ion position within the trap 30 is controlled so that the ions exit through one side (the left hand side as shown in FIG. 7 ) of the exit aperture 29 . Control of the position of the ions within the ion trap may be achieved in a number of ways, such as by applying differing voltages to electrodes (not shown) on the ends of the ion trap 30 . In one particular embodiment, ions may be ejected in a compact cylindrical distribution from the middle of the ion trap 30 whilst being recaptured as a much longer cylindrical distribution (as a result of divergence and aberrations within the system) of a much greater angular size. Modified ion optics 32 ′ are sited downstream of the exit from the ion trap 30 , and, downstream of that, a first modulator/deflector 100 ″ directs the ions into the EST 40 . Ions are reflected along the axis of the EST 40 . As an alternative to the directing of the ions from the ion trap 30 into the EST 40 , the ions may instead be deflected by a deflector 100 ″ downstream of the ion optics 32 ′ into an Orbitrap mass analyser 70 or the like. In the embodiment of FIG. 7 , the ion trap 30 operates both as a decelerator and as an ion selector. The extraction (dc) potential across the ion trap 30 is switched off and the trapping (rf) potential is switched on at the exact point at which ions of interest come to rest in the ion trap 30 following their return from the EST 40 . To inject into and eject from the EST 40 , the voltages on the mirror within the EST 40 ( FIG. 3 ) which is closest to the lenses is switched off in a pulsed manner. After ions of interest are captured in the ion trap 30 , they are accelerated towards the fragmentation cell 50 on either side of the ion trap 30 , where fragment ions are generated and then trapped. After that, the fragment ions can be transferred to the ion trap 30 once more. By ejecting ions from a first side of an elongate slot and capturing them back at or towards a second side of such a slot, the path of ejection from the ion trap 30 is not parallel to the path of recapture into that trap 30 . This in turn may allow injection of the ions into the EST 40 at an angle relative to the longitudinal axis of that EST 40 , as is shown in the embodiments of FIGS. 4 and 5 . Of course, although a single slot-like exit aperture 29 is shown in FIG. 7 , with ions exiting it towards a first side of that slot but being received back from the EST 40 via the other side of that slot, two (or more) separate but generally adjacent transport apertures (which may or may not then be elongate in the direction orthogonal to the direction of travel of ions through them) could instead be employed, with ions exiting via a first one of these transport apertures but returning into the ion trap 30 via an adjacent transport aperture. Indeed, not only could the slot like exit aperture 29 of FIG. 7 be subdivided into separate transport apertures spaced in an generally orthogonal direction to the direction of travel of the ions during ejection and injection, but the curved ion trap 30 of FIG. 7 could itself be subdivided into separate segments. Such an arrangement is shown in FIG. 8 . The arrangement of FIG. 8 is very similar to that of FIG. 7 , in that the spectrometer comprises an ion source 20 which supplies ions to a pre-trap which is a auxiliary ion storage device 60 . Downstream of that pre-trap/auxiliary ion storage device 60 is a ion trap 30 ′ (to be described further below) and a fragmentation cell 50 . As with the arrangement of FIG. 7 , the fragmentation cell 50 in FIG. 8 could be located on either side of the ion trap 30 ′ though in the embodiment of FIG. 8 the fragmentation cell 50 is shown between the ion source 20 and the ion trap 30 ′, the ion trap 30 ′ and the fragmentation cell 50 being separated by an optional ion deceleration arrangement 80 . Downstream of the ion trap 30 is a first modulator/deflector 100 ′″ which directs the ions into the EST 40 from an off axis direction. Ions are reflected along the axis of the EST 40 . To eject the ions from the EST 40 back to the ion trap 30 , a second modulator/deflector 100 ″ in the EST 40 is employed. As an alternative to the directing of the ions from the ion trap 30 into the EST 40 , the ions may instead be deflected by the deflector 100 ′″ into an Orbitrap mass analyser 70 or the like. The curved ion trap 30 ′ comprises in the embodiment of FIG. 8 , three adjoining segments 36 , 37 , 38 . The first and third segments 36 , 38 each have an ion transport aperture so that ions are ejected from the ion trap 30 ′ via the first transport aperture in the first segment 36 , into the EST 40 , but are received back into the ion trap 30 ′ via a second, spatially separate transport aperture in the third segment 38 . To achieve this, the same RF voltage may be applied to each segment of the ion trap 30 ′ (so that in that sense the ion trap 30 ′ acts as a single trap despite the several trap sections 36 , 37 , 38 ) but with different DC offsets applied to each section so that the ions are not distributed centrally in the axial direction of the curved ion trap 30 ′. In use, ions are stored in the ion trap 30 ′. By suitable adjustment of the DC voltage applied to the ion trap segments 36 , 37 , 38 , ions are caused to leave the ion trap 30 ′ via the first segment 36 for off axis injection into the EST 40 . The ions return to the ion trap 30 ′ and enter via the aperture in the third segment 38 . By maintaining the DC voltage on first and second segments 36 and 37 at a lower amplitude than the DC voltage applied to the third segment 38 when the ions are re-trapped from the EST 40 , the ions can be accelerated (eg by 30-50 ev/kDa) along the curved axis of the ion trap 30 ′ so that they undergo fragmentation. In this manner the ion trap 30 ′ is operable both as a trap and as a fragmentation device. The resultant fragment ions are then cooled and squeezed into the first segment 36 by increasing the DC offset voltage on the second and third segments 37 , 38 relative to the voltage on the first segment 36 . For optimal operation, fragmentation devices in particular require that the spread of energies of the ions injected into them is well controlled and held within a range of about 10-20 eV, since higher energies result in only low-mass fragments whereas lower energies provide little fragmentation. Many existing mass spectrometer arrangements, as well as the novel arrangements described in the embodiments of FIGS. 1 to 7 here, on the other hand, result in an energy spread of ions arriving at a fragmentation cell far in excess of that desirable narrow range. For example, in the arrangement of FIGS. 1 to 7 , the ions may spread in energy in the ion trap 30 , 30 ′ due to spatial spread in that trap; due to space charge effects (e.g. Coulomb expansion during multiple reflections) in the EST 40 , and due to the accumulated effect of aberrations in the system. In consequence some form of energy compensation is desirable. FIGS. 9 to 11 show some specific but schematic examples of parts of an ion deceleration arrangement 80 for achieving that goal, and FIGS. 12 and 13 show energy spread reduction and spatial spread for a variety of different parameters applied to such ion deceleration arrangements. In order to achieve a suitable level of energy compensation, employing some of the embodiments described above, it is desirable to increase the ion energy dispersion. In other words, the beam thickness for a hypothetical monoenergetic ion beam is preferably smaller than the separation of two such hypothetical monoenergetic ion beams by the desired energy difference of 10-20 eV as explained above. Although a degree of energy dispersion could of course be achieved by physically separating the fragmentation cell 50 from the ion trap 30 or EST 40 by a significant distance (so that the ions can disperse in time), such an arrangement is not preferred as it increases the overall size of the mass spectrometer, requires additional pumping, and so forth. Instead it is preferable to include a specific arrangement to allow deliberate energy dispersion without unduly increasing the distance between the fragmentation cell 50 and the component of the mass spectrometer upstream from it (ion trap 30 or EST 40 ). FIG. 9 shows one suitable device. In FIG. 9 , an ion mirror arrangement 200 forming an optional part of the highly schematically represented ion deceleration arrangement 80 of FIGS. 2-7 is shown. The ion mirror arrangement 200 comprises an array of electrodes 210 terminating in a flat mirror electrode 220 . Ions are injected into the ion mirror arrangement from the EST 40 and are reflected by the flat mirror electrode 220 resulting in increased dispersion of the ions by the time they exit back out of the ion mirror arrangement and arrive at the fragmentation cell 50 . An alternative approach to the introduction of energy dispersion is shown in FIG. 11 and described further below. Once the degree of energy dispersion has been increased for example with the ion mirror arrangement 200 of FIG. 9 , ions are next decelerated. In general terms this may be achieved by applying a pulsed DC voltage to a decelerating electrode arrangement such as that illustrated in FIG. 10 and labelled 250 . The decelerating electrode arrangement 250 of FIG. 10 comprises an array of electrodes with an entrance electrode 260 and an exit electrode 270 between which is sandwiched a ground electrode 280 . Preferably the entrance and exit electrodes are combined with differential pumping sections so as to reduce the pressure gradually between the (upstream) ion mirror arrangement 200 at a relatively low pressure, the decelerating electrode arrangement 250 at an intermediate pressure, and the relatively higher pressure required by the (downstream) fragmentation cell 50 . By way of example only, the ion mirror arrangement 200 may be at a pressure of around 10 −8 mBar, the decelerating electrode arrangement 250 may have a lower pressure limit of around 10 −5 mBar rising to around 10 −4 mBar via differential pumping, with a pressure in the range of 10 −3 to 10 −2 mBar or so in the fragmentation cell 50 . To provide pumping between the exit of the decelerating electrode arrangement 250 and the fragmentation cell 50 , an additional RF only multipole such as, most preferably, an octapole RF device, could be employed. This is shown in FIG. 11 to be described below. To achieve deceleration, DC voltages on one or both of the lenses 260 , 270 are switched. The time at which this occurs depends upon the specific mass to charge ratio of ions of interest. In particular, when ions enter a decelerating electric field, higher energy ions overtake lower energy ions and thus move to a greater depth in the deceleration field. After all the ions of this particular m/z enter the deceleration field, the field is switched off. Therefore ions with initially higher energy experience a higher drop in potential relatively to ground potential than the lower energy ions, thus making their energies equal. By matching the potential drop to the energy spread upon exit from the mass selector, a significant reduction of the energy spread may be achieved. It will be understood that this technique permits energy compensation for ions of a certain range of mass to charge ratios, and not for an indefinitely wide range of different mass to charge ratios. This is because in a finite decelerating lens arrangement, only ions of a certain range of mass to charge ratios will be caused to undergo an amount of deceleration that can be matched to their energy spread. Any ions of widely differing mass to charge ratios to that selected will of course either be outside of the decelerating lens when it is switched, or likewise undergo a degree of deceleration but, having a largely different mass to charge ratio, the amount of deceleration will not then be balanced by the initial energy spread, i.e. the deceleration and penetration distance of higher energy ions will not then be matched to the deceleration and penetration distance of lower energy ions. Having said that, however, the skilled person will readily understand that this does not prohibit the introduction of ions of widely differing mass to charge ratios into the ion deceleration arrangement 80 , only that only ions of one particular range of mass to charge ratios of interest will undergo the appropriate degree of energy compensation to prepare them properly for the fragmentation cell 50 . Thus, the ions can either be filtered upstream of the ion deceleration arrangement 80 (so that only ions of a single mass to charge ratio of interest enter it in a given cycle of the mass spectrometer) or alternatively a mass filter can be employed downstream of the ion deceleration arrangement 80 . Indeed, it is even possible to use the fragmentation cell 50 itself to discard ions not of the mass to charge ratio of interest and which have been suitably energy compensated. FIG. 11 shows an alternative arrangement for decelerating ions and also optionally defocusing them as well. Here, the defocusing is achieved within the EST 40 (only a part of which is shown in FIG. 11 ) by pulsing the DC voltage on one of the electrostatic mirrors 42 , 44 ( FIG. 3 ) at a time when ions of a mass to charge ratio of interest are in the vicinity of that electrostatic mirror 42 , 44 (because of the manner in which the EST 40 operates, the time at which ions of a particular m/z arrive at the electrostatic mirrors 42 , 44 is known). Applying a suitable pulse to that electrostatic mirror 42 or 44 results in that mirror 42 , 44 having a defocusing rather than a focusing effect on those ions. Once defocused, the ions can then be ejected out of the EST by applying a suitable deflecting field to the deflector 100 / 100 ′/ 100 ″. The defocused ions then travel towards a decelerating electrode arrangement 300 which decelerates ions of the selected m/z as explained above in connection with FIG. 10 , by matching the initial energy spread to the drop in potential across the electric field defined by the decelerating electrode arrangement 300 . Finally, ions exit the decelerating electrode arrangement 300 through termination electrodes 310 and pass through an exit aperture 320 into an octapole RF only device 330 to provide the desirable pumping described above. FIGS. 12 and 13 show plots of energy spread and spatial spread of ions of a specific mass to charge ratio, respectively, as a function of switching time of the DC voltage applied to the ion decelerating electrodes. It can be seen from FIG. 12 that the reduction in energy spread achieved by an embodiment of the present invention can be as much as a factor of 20, reducing a beam with +/−50 eV spread to one of +/−2.4 eV. A longer switching time produces a smaller spatial spot size but a larger final energy spread with the particular decelerator system described here. The example is given here to show that beam characteristics other than energy spread must be considered, not to suggest that deceleration for optimal final energy spread always produces an increase in spatial spread of the final beam. Other designs of decelerating lens used with other energy defocused beams could produce a still greater reduction in energy spread. Those skilled in the art will realise that there are many potential uses for the invention as a result. The use for which the invention was particularly addressed was that of improving the yield and type of fragment ions produced in a fragmentation process. As was noted earlier, for efficient fragmentation of parent ions, 10-20 eV ion energies are required, and clearly a great many ions in a beam having +/−50 eV energy spreads will be well outside that range. Ions having too high an energy predominantly fragment to low mass fragments which can make identification of the parent ion difficult, whilst a higher proportion of ions of low energy do not fragment at all. Without energy compensation, a parent ion beam having +/−50 eV energy spread directed towards a fragmentation cell would either produce a high abundance of low mass fragments, if all the beam were allowed to enter the fragmentation cell, or if only ions having the highest 20 eV of energy were allowed to enter (by use of a potential barrier prior to entry, for example) a great many ions would have been lost, and the process would be highly inefficient. The inefficiency would depend upon the energy distribution of the ions in the beam, with perhaps 90% of the beam being lost or unable to fragment due to insufficient ion energy. By using the foregoing techniques, fragmentation of ions in the fragmentation cell may thereby be avoided if it is desired to pass ions through the fragmentation cell 50 (or store them there) in a given cycle of the mass spectrometer intact. Alternatively, control over the fragmentation may be improved when it is desired to carry out MS/MS or MS^n experiments. Other uses for the ion deceleration technique described may be found in other ion processing techniques. Many ion optical devices can only function well with ions having energies within a limited energy range. Examples include electrostatic lenses, in which chromatic aberrations cause defocusing, RF multipoles or quadrupole mass filters in which the number of RF cycles experienced by the ions as they travel the finite length of the device is a function of the ion energy, and magnetic optics which disperse in both mass and energy. Reflectors are typically designed to provide energy focusing so as to compensate for a range of ion beam energies, but higher order energy aberrations usually exist and an energy compensated beam such as is provided by the present invention will reduce the defocusing effect of those aberrations. Again, those skilled in the art will realise that these are only a selection of possible uses for the described technique. Returning now to the arrangements of FIGS. 2 and 4 - 8 , in general terms, effective operation of each of the gas-filled units shown in these Figures depends upon the optimum choice of collision conditions and is characterised by collision thickness P·D, where P is the gas pressure and D is the gas thickness traversed by ions (typically, D is the length of the unit). Nitrogen, helium or argon are examples of collision gases. In the presently preferred embodiment, it is desirable that the following conditions are approximately achieved: In the pre-trap 24 , it is desirable that P·D>0.05 mm·torr, but is preferably <0.2 mm·torr. Multiple passes may be used to trap ions, as described in our co-pending Patent Application No. GB0506287.2. The ion trap 30 preferably has a P·D range of between 0.02 and 0.1 mm·torr, and this device could also extensively use multiple passes. The fragmentation cell 50 (using collision-induced dissociation, CID) has a collision thickness P·D>0.5 mm·torr and preferably above 1 mm·torr. For any auxiliary ion storage device 60 employed, the collision thickness P·D is preferably between 0.02 and 0.2 mm torr. On the contrary, it is desirable that the electrostatic trap 40 is sustained at high vacuum, preferably at or better than 10 −8 torr. The typical analysis times in the arrangement of FIG. 2 are as follows: Storage in the pre-trap 24 : typically 1-100 ms; Transfer into the curved trap 30 : typically 3-10 ms; Analysis in the EST 40 : typically 1-10 ms, in order to provide selection mass resolution in excess of 10,000; Fragmentation in the fragmentation cell 50 , followed by ion transfer back into the curved trap 30 : typically 5-20 ms; Transfer through the fragmentation cell 50 into a second ion storage device 60 , if employed, without fragmentation: typically 5-10 ms; and Analysis in a mass analyser 70 of the Orbitrap type: typically 50-2,000 ms. Generally, the duration of a pulse for ions of the same m/z should be well below 1 ms, preferably below 10 microseconds, while a most preferable regime corresponds to ion pulses shorter than 0.5 microseconds (for m/z between about 400 and 2000). In alternative terms and for other m/z, the spatial length of the emitted pulse should be well below 10 m, and preferably below 50 mm, while a most preferable regime corresponds to ion pulses shorter than 5-10 mm. It is particularly desirable to employ pulses shorter than 5-10 mm when employing Orbitrap and multi-reflection TOF analysers. Although one specific embodiment has been described, the skilled reader will readily appreciate that various modifications could be contemplated.

A method of improving the detection limits of a mass spectrometer by: generating sample ions from an ion source; storing the sample ions in a first ion storage device; ejecting the stored ions into an ion selection device; selecting and ejecting ions of a chosen mass to charge ratio out of the ion selection device; storing the ions ejected from the ion selection device in a second ion storage device without passing them back through the ion selection device; repeating the preceding steps so as to augment the ions of the said chosen mass to charge ratio stored in the second ion storage device; and transferring the augmented ions of the said chosen mass to charge ratio back to the first ion storage device for subsequent analysis.

BACKGROUND OF THE INVENTION Iodine is a non-metallic element of the halogen family, and is the only halogen that is solid at ordinary temperatures. Iodine has been shown to have a range in valence of from -1 to +7, and compounds thermodynamically stable with respect to their constituent elements are known to exist for all of the oxidation states of iodine. Iodine was discovered early in the 19th century, and the first practical therapeutic application of iodine was as a remedy for goiter. This use was followed shortly thereafter with use as a germicide for treatment of wounds. It was during the American war between the states that the first wide-spread use of iodine as an antiseptic and germicide was developed for the treatment of battle wounds. Since that time, iodine has been recognized to be a preferred germicide, but because of certain inherent chemical, physical and biological properties, the antiseptic degerming use of iodine for humans and animals has been limited. Elemental iodine has a high vapor pressure which results in pharmaceutical compositions having varying germicidal potency, since the iodine content volatilizes from an antiseptic preparation upon aging. Moreover, the high vapor pressure of iodine limits its use in closed compartments, such as body cavities or under a bandage, because of the corrosive destruction and irritation of skin, mucous membranes, and other vital tissues by the elemental iodine itself. While the overall systemic toxicity of iodine is low, fatalities have occurred after accidental ingestion of iodine solutions. However, the pathological changes recorded for fatal cases of iodine poisoning are largely the result of tissue hypoxia and local corrosive destructive effects, rather than systemic iodine poisoning. Another limitation for the germicidal use of iodine is its high aqueous insolubility (0.034% at 25° C.). While the aqueous solubility of iodine may be increased through the use of alcohol (as for example, tincture of iodine) or through the use of inorganic metallic salts as solubilizing agents (as for example, sodium iodide and/or potassium iodide in the preparation of Lugols' Solution), such iodine solutions also possess the same toxic tissue manifestation which generally limit the use of iodine germicidal solutions. When alcohol is used as a solvent for iodine, the use of such preparations on abraded and injured skin or mucous membrane is painful and damaging. Further, as the alcohol evaporates, the iodine content concentrates which increases the incidence of burning, corrosive destruction, and staining of tissues. Metallic iodides have been used to solubilize elemental iodine in water through the direct formation of a water-soluble iodine complex formed between the diatomic iodine (I 2 ) and the iodide ion (I - ) to form I 3 - ions Such aqueous iodine solutions have not modified the toxic tissue reactions of elemental iodine, so that burning and staining still occur. In fact, such undesirable reactions are now more frequent, since larger concentrations of elemental iodine are utilized to prepare the aqueous iodine germicidal compositions. Iodine in aqueous solution dissociates to equilibrium as follows: ##STR1## with the equilbrium constant (K 1 ) being about 4×10 -46 depending upon the temperature. In aqueous media, the dissociation phenomena for diatomic iodine is further complicated by the formation of several species of iodide ion, the most significant of which is the tri-iodide ion. The equilibrium constant (K 2 ) is approximately 7.5×10 2 for the following reaction: ##STR2## It is preferable to combine these equilibrium reactions when describing the dissociation of diatomic iodine in aqueous solutions as: ##STR3## the equilibrium constant (K 3 ) being approximately 3×10 -43 . Iodine is a mild oxidizing agent in acidic solution, with a redox equilibrium potential of 0.534 V at 25° C. for the iodine-iodide ion couple. Iodine will readily oxidize sulfite to sulfate, and thiosulfate to tetrathionate, while ferric and cupric salts are reduced in acidic solution by the iodide ion, to form free iodine. In dilute solutions, iodine completely oxidizes sulfur dioxide to sulfuric acid, whereas iodides reduce sulfuric acid to sulfur dioxide, sulfur and even hydrogen sulfide, with the liberation of free iodine. In neutral or slightly alkaline aqueous solutions, iodine exerts a somewhat stronger oxidizing action because of the formation of hypo-iodite ion, in accordance with the following reaction: I.sub.2 +2OH.sup.-→I.sup.- +IO.sup.- +H.sub.2 O Such aqueous solutions are strong iodinating agents, and cause redox changes in body proteins and other biological substances within the alkaline physiologic pH range. Iodine will add to unsaturated linkages in tissue proteins, to cause denaturation which interrupt essential physiological reactions. In an effort to overcome the noxious tissue toxicity observed for aqueous and hydroalcoholic solutions of iodine, while at the same time maintaining the germicidal and microbicidal activity of elemental iodine, water-soluble organic complexes of iodine with organic polymers were prepared. Combinations of elemental iodine and certain organic polymers, as for example polyvinylpyrrolidone and detergent polymers, has been shown to increase the aqueous solubility of elemental iodine. Such polymer-iodine complexes were termed iodophors. The organic polymers used to form an iodophor comprise a broad range in molecular weight and chain length, and may be either ionic or nonionic in character, as well as possessing either surfactant or non-surfactant properties. A loose bond forms between the iodine and organic polymer to form the complex or iodophor, and aqueous solutions of up to 30% by weight in iodine content may be prepared (all percents are by weight herein, except as otherwise noted). The general class of organic iodophor compounds comprises two distinct polymer groups: Polyvinylpyrrolidone, a non-detergent, non-ionic and non-surface active polymer; and a broad variety of detergent/surface-active polymers, including non-ionic, anionic, and cationic surface-active polymers. Both polymer groups are complexed with elemental iodine to form the iodophor. Anionic surface-active agents are generally not capable of providing stable iodine complexes. However, certain anionic surface-active agents, such as enumerated in U.S. Pat. No. 3,039,916, have been found to be suitable for forming iodine complexes for germicidal use. Non-detergent, non-ionic organic polymers have generally not been employed as a carrier for iodine in germicidal use. Only one such polymer, polyvinylpyrrolidone, has to date been found satisfactory to complex with iodine to form useful iodophor germicidal compositions. Polyvinylpyrrolidone is a non-ionic, non-detergent, water-soluble synthetic organic polymer characterized by its unusual complexing ability and colloidal properties together with physiological inertness. The commonly employed, polyvinylpyrrolidone-iodine (PVP-I) complex contains from about 9 to 12% of titratable iodine, although polymer iodine complexes with both greater and lesser amounts of iodine are known. Polyvinylpyrrolidone iodine is a highly-effective germicide, providing a broad spectrum of microbicidal action against virtually all microbes. Polyvinylpyrrolidone-iodine (PVP-I) exhibits low systemic toxicity, and is essentially non-irritating to mammalian tissue, in addition t being non-sensitizing and not causing pain when applied to wounds or mucous membrane. Thus polyvinylpyrrolidone iodone (PVP-I) is extensively used as in important germicidal agent in man and animals, as well as in environmental uses. Polyvinylpyrrolidone iodine and the preparation thereof is described in U.S. Pat. No. 2,739,922. However, no other member of the non-detergent, non-ionic class of organic polymers has been found to be suitable for such antiseptic purposes. The general method of preparing an iodophor complex is to bring the elemental diatomic iodine into intimate contact with the selected polymer either in the dry or powder form, or in the presence of a suitable solvent. Heat may be used to accelerate formation of the complex. Upon completion of the reaction, the iodophor complex of the respective polymeric carrier with iodine is obtained in certain reproducible proportions of one to the other. Studies have demonstrated that the microbicidal potency of iodophor germicidal preparations is essentially the same as that known for aqueous and/or alcoholic solutions of elemental iodine, despite the modified tissue toxicity of the iodophors. Superiority of iodophor germicidal preparations over the aqueous and/or alcoholic inorganic elemental iodine solutions have been demonstrated to reside essentially in decreased toxicity, reduced tissue irritation, lowered iodine vapor pressure, as well as in the non-staining feature of skin and natural fabrics of the iodophor preparations. Iodophor preparations are described in terms of available or titratable iodine which is considered to be the iodine released from the complex to exert its germicidal activity. However, such available iodine determinations do not either reflect the total iodine content of the iodophor or its germicidal potency. As noted above, the most suitable polymer for the formation of iodophors is polyvinylpyrrolidone, which is the only nondetergent, nonionic organic polymer suitable for the formation of antiseptic iodophors. SUMMARY OF THE INVENTION It is accordingly a primary object of the present invention to provide a new nondetergent, nonionic polymer which can form complexes with elemental iodine to provide highly effective iodine-containing germicidal preparations. It is another object of the present invention to provide nonionic, nondetergent organic carbohydrate polymers which complex with elemental iodine to give effective iodophor preparations. It is yet another object of the present invention to provide new nonionic, nondetergent iodophor preparations and germicidal and antiseptic compositions thereof. It is still another object of the present invention to provide methods of producing the new iodophors of the invention. Other objects and advantages of the presen invention will be apparent from a further reading of the specification and of the appended claims. With the above and other objects in view, the present invention mainly comprises complexes of iodine with polydextrose or with the carbohydrate polymer produced by the copolymerization of sucrose and epichlorohydrin. Polydextrose is a non-nutritive, polysaccharide, carbohydrate polymer prepared by the condensation polymerization of saccharides in the presence of polycarboxy acid catalysts, under reduced pressure. Polydextrose is described in U.S. Pat. Nos. 3,766,105 and 3,786,794, and is available from Pfizer, Inc., New York, N.Y. Polydextrose is a white-to-tan powder occurring in both water soluble and water insoluble forms. The average molecular weight for polydextrose is from about 1,500 to 36,000, with water soluble polydextrose having an average molecular weight of about 2,500 to 18,000 and water insoluble polydextrose having an average molecular weight of between 6,000 to 36,000. When the number average molecular weight of polydextrose is determined by the modified reducing end group method of Isbel (J. Res. Nat'l. Bur. Standards 24,241 (1940)), the average molecular weight of polydextrose will usually range from about 1,000 to 24,000, with most of the molecular weight falling within the range of from 4,000 to 12,000. When the modified reducing end group method is used to determine the number average molecular weight of polydextrose, the number average weight has been shown to be a multiple of 1.5 of the number average molecular weight found by the modified reducing and group method of Isbel. However, any one of the well known methods for polymer molecular weight determination may be used to characterize the number average molecular weight for polydextrose. It is clear from the schematic formula of polydextrose (provided by Pfizer) that primarily 1-6 linkages predominate because of the reactivity of the primary hydroxy groups, although other glucosidic linkages may occur. In the soluble form of polydextrose, each of the present acid moieties is esterified to the polydextrose, however when the acid moiety is esterified to more than one polydextrose moiety, cross-linking will occur. Synthetic polydextrose is not affected by amylolytic enzymes, while animal nutrition and radioactive trace studies have demonstrated that polydextrose is substantially non-toxic. The usually commercially available polydextrose polymer is a low molecular weight, water-soluble, randomly bonded polymer of glucose containing minor amounts of sorbitol end groups and citric acid residues attached to the polymer by mono- and di-ester bonds. The effect of the random bonding and occasional di-ester cross-linking in polydextrose, is a polymer more resistant to acid or enzyme hydrolysis than other carbohydrate polymers such as starch. The average molecular weight of commercially-available polydextrose is 1,500, ranging from 162 to approximately 20,000. This molecular weight range ensures a high degree of water-solubility and relatively low viscosity, with principal properties similar to sucrose but without the sweetness in taste. The molecular weight range for commercially available polydextrose is: ______________________________________MOLECULAR WEIGHT RANGE PERCENT______________________________________ 162-5,000 88.7 5,000-10,000 10.010,000-16,000 1.216,000-18,000 0.1______________________________________ Polydextrose contains trace amounts of 5-hydroxymethylfurfural and a small amount of levoglucosan (1-6 anhydroglucose), in addition to smaller amounts of unreacted starting ingredients such as glucose, sorbitol, and citric acid. When polydextrose polymer is combined with elemental iodine, the resultant polydextrose-iodine complex (PDI) is formed. This polydextrose iodine complex is a tan-to-amber colored powder which starts to melt at about 93° C., and by 127° C., completely forms a red liquid. Polydextrose iodine powder is highly soluble in water, and at room temperature results in a reddish-brown colored aqueous solution containing as much as 80% by weight of polydextrose iodine. Solutions of even greater concentration may be prepared. This increased water solubility contrasts sharply with the well known aqueous insolubility of iodine which is soluble in water only to the extent of 0.034%. This increased water solubility establishes that complexing has occurred during the reaction of polydextrose with iodine to form a new compound which has new and advantageous properties. Aqueous solutions of polydextrose-iodine (PDI) are acidic in nature, but may be buffered over the entire physiological acid pH range, without interfering with complex formation or germicidal action. The infrared spectrum of polydextrose iodine utilizing the potassium bromide (KBr) pellet technique over the range of from 4,000 cm-1 to 200 cm-1 reveals a very slight shoulder with an increased intensity of the peak at 800 cm-1 300 cm-1 . When polydextrose iodine is dissolved in water the titratable iodine content may be determined by the well known method of iodine titration with sodium thiosulfate solution. The tests have determined that polydextrose iodine provides sufficient equilibrium iodine for germicidal purposes so that the substance is an effective germicide. Conductance tests carried out on polydextrose iodine have confirmed that the polydextrose is definitely complexed with triiodide (I -3 ) and/or iodide (I - ) because the equivalence conductance at zero concentration is significantly less than that for iodine solution (Lugol's Solution). It has further been noted that the ratio of free ions to bound ions, as the concentration decreases, is constant. Polydextrose iodine shows lower free ion concentration than iodine solution. In accordance with the further embodiment of the present invention, complexes are provided of iodine with the polymer produced by the copolymerization of sucrose and epichlorohydrin. The molecules of such polymer have a branched structure and a high content of hydroxyl groups which results in a very good solubility in aqueous media of the polymer. Such polymers obtained by the copolymerization of sucrose epichlorohydrin have been marketed by Pharmacia Fine Chemicals AB of Uppsala, Sweden under the name "Ficoll", and for convenience of discussion in the specification hereof, reference will be made to Ficoll rather than to the "polymer prepared by copolymerization of sucrose and epichlorohydrin". The molecules of Ficoll have a branch structure, with a high content of hydroxyl groups resulting in very good solubility in aqueous media. There are no ionized groups present in Ficoll, as this is also a non-ionic, non-detergent, nonsurfactant organic carbohydrate polymer as polydextrose. The preparation and properties of Ficoll may be found in "Ficoll For Cell Research" published by Pharmacia Fine Chemicals. The Ficoll-Iodine complex exhibits the same properties as the PDI complex with respect to germicidal activity and delivery of iodine. With the determination of equilibrium and method for delivery being determined by the same methods as for the PDI complex. Both the polydextrose-iodine (PDI) and Ficoll-Iodine (FI) complexes provide for smooth, even, delivery of antiseptic iodine when applied to living or inanimate surfaces, over a period of time, without any irritability or toxicity effects. This is a tremendous improvement over any of the previously known inorganic iodine-containing germicidal preparations, which either result in high toxicity, skin or surface irritation, or lack of control of delivery of the antiseptic iodine over a period of time. As previously noted, it was totally unexpected that any non-detergent, non-ionic, non-surfactant organic polymers other than polyvinylpyrrolidone would be suitable for preparation of an iodophor complex. However, it has now been found that polydextrose and Ficoll polymer are both suitable for preparing the requisite complexes, for adequate, effective, delivery of germicidal action. In addition to forming similar complexes to PVP-I, both polydextrose polymer and Ficoll polymer have a greater water-solubilizing effect on elemental iodine than polyvinylpyrrolidone, the elemental iodine having a very low solubility in water. Thus, the polymer iodine complexes of PDI and FI have practically no free elemental iodine in the solid state when subjected to an extraction with n-heptane, since the complexed iodine in the PDI or the FI complexes is in tri-iodide anionic equilibrium which is insoluble in n-heptane and other organic solvents. DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS The following is a more detailed description of the present invention which is merely intended as exemplary, and not as limiting the scope of the invention in any way. As noted above, polydextrose is a water soluble, randomly bonded polymer of D-glucose containing minor amounts of sorbitol end groups and citric acid residues attached to the polymer by mono and di-ester linkage. Polydextrose contains every possible type of glucosidic linkage. Because of the reactivity of the primary hydroxy groups, the 1-6 bonding predominates in polydextrose. The result of this random bonding and occasional di-ester cross-linking is a polymer more resistant to acidic or enzyme hydrolysis than a polymer such as starch. Synthesis of polydextrose polymer, as noted above, is disclosed in U.S. Pat. No. 3,766,165 and U.S. Pat. No. 3,876,794, while the polymer itself is available from Pfizer. Previous known uses include that of a multipurpose food additive, such as a reduced caloric bulking agent. Such use includes additives to baked goods, chewing gum, confections, salad dressings, dairy products, hard candy, etc., and other types of edible products. Overall, polydextrose is stable over time, however long term storage at elevated temperatures can result in some discoloration. Polydextrose forms a clear melt above 130° C., in a similar manner to sucrose. Polydextrose type N available from Pfizer is a clear, straw-colored 70% solution prepared by partially neutralizing polydextrose with potassium hydroxide. Viscosity of this particular solution of polydextrose type N is somewhat greater than that of sugar or sorbitol solutions of equal concentrations. Polydextrose can also function as a humectant, with the powder absorbing moisture under normal atmospheric conditions until equilibrium is reached. A 10% W/V aqueous solution of polydextrose has a pH of about 2.5 to 3.5. Safety of polydextrose has been established by 32 different studies in five species of animals and in 8 human studies. Most of the polydextrose product passes through a living body unabsorbed. The principal utilization pathway for the remainder thereof involves metabolism by intestinal micro-organism to form carbon dioxide and volatile fatty acids which can then be absorbed and utilized as an energy source source by a living body. Use of polydextrose has been approved by the FDA which defines the same as a partially metabolizable water-soluble polymer prepared from D-glucose with small amounts of sorbitol and citric acid. Polydextrose may be partially neutralized with potassium hydroxide. When 0.10 g polydextrose is dissolved in 25 ml of water and analyzed for ultraviolet (UV) characteristics, the absorbence spectrum from 800-190 nm is obtained. Two peaks are observed in the region 190-300 nm with maxima at 193 nm and 281 nm. The absorbence intensity is 2.87 and 0.144 respectively. Concerning the infrared spectrum, percent transmission is measured fora polydextrose-KBr pellet over an infrared spectrum from 400-200 cm -1 . Four regions of infrared absorbence are observed, namely 3450-2500 cm -1 , 1800-1200 cm -1 , 1200-800 cm -1 , and 800-300 cm -1 . One broad peak of strong intensity with a narrow weaker shoulder at 2970 cm -1 , a moderate, fairly broad peak at 1600cm -1 , and a strong, fairly broad peak at 1000 cm -1 are all observed. Viscosity of polydextrose as a function of its concentration, was determined by preparing varying solutions of polydextrose containing from 1% w/v to 60% w/v. The relative viscosities of these solutions were determined at 25° C. and plotted as a function of concentration. Also, the viscosity of polydextrose, as compared to sorbitol and sucrose, is shown in the following Table I: TABLE I______________________________________VISCOSITY (CENTIPOISES) POLY-% POLYMER W/W SORBITOL SUCROSE DEXTROSE______________________________________10% -- -- 1030% -- -- 1540% -- -- 2450% 10 24 4660% 24 40 10070% 120 300 800______________________________________ The above determined viscosities are available from Pfizer. Ficoll, has an average molecular weight of 400,000±100,000, an intrinsic viscosity of about 0.7 dl/g, and a specific rotation [α] 20 D of +56.5°. There is less than 1% dialysable material in polysaccharide Ficoll polymer, including the sodium chloride present therein. Reactivity and stability of Ficoll are determined by the hydroxy groups and the glycosidic groups present in the sucrose residues therein. Ficoll is stable in both alkaline and neutral solutions. At pH values lower than 3, Ficoll is rapidly hydrolized, especially at elevated temperatures. However, Ficoll can be sterilized in neutral solutions by autoclaving at 110° C. for 30 minutes without degradation. As available from Pharmacia Fine Chemicals, Ficoll is delivered as a spray-dried powder and thus readily soluble in aqueous media, when added slowly with concomitant stirring. Concentrations of up to 50% w/v of Ficoll in solution can be obtained. The relative viscosities of Ficoll solution are at various concentrations are illustrated in Table II below: TABLE II______________________________________FICOLL PERCENT (w/v) 10 20 30 40 50______________________________________n.sub.r at 20° 5 20 60 80 600______________________________________ Unlike sucrose itself, Ficoll solutions have low osmotic pressure, while densities of sucrose and Ficoll are comparable. Because of high molecular weight and low content of dialyzable material, Ficoll has a much lower permeability toward cell membranes than sucrose, for example. Ficoll has previously been used primarily in the field of centrifugation in dense media, where Ficoll has been used for separation and isolation of cells and subcellular particles. Ficoll may also be used as a stabilizing agent in protein solutions, and in dialysis. Other compatible ingredients may be incorporated into the iodophor preparation formed from iodine and either polydextrose or Ficoll's polymer. Such compatible ingredients include buffers, supplementary surfactants, and additional non-aqueous solvent. An example of such solvent is glycerin. The amount of iodine that can be incorporated in the new iodophors of the present invention, that is the iodophors of polydextrose or of Ficoll polymer would be the same as in the case of other known iodophors such as polyvinylpyrrolidone iodine. In general, the amount of iodine is between 1-20%, preferably 2-16%, most preferably 2-10%. The complex of polydextrose and/or polysaccharide Ficoll polymer with iodine may be prepared through the interaction of elemental iodine with polydextrose and/or Ficoll polymer in its solid state. The rate of such reaction (formation of the requisite complex) may be determined by controlling the temperature. Such a reaction will proceed slowly at room temperature, and will be accelerated at elevated temperatures. The complex is preferably prepared by initially dissolving the requisite quantity of polydextrose or Ficoll polymer in a polar solvent such as water, followed by addition of elemental iodine under vigorous stirring until dissolution is complete. Elemental iodine may be introduced into such a polar solvent in the form of an aqueous solution itself, such as Lugols Solution, or as an aqueous solution of sodium iodide-iodine. Other suitable solutions for the introduction of iodine into the polar solvent to form the iodophor preparation, include potassium iodide-iodine, and hydriodic acid solutions. In this instance, the advantageous iodophor preparation results from the interaction of the elemental iodine, alkali metal iodide and polydextrose and/or Ficoll polymer in the polar solvent, e.g. water solution. In this manner, polydextrose iodine preparations may be prepared with up to about 20% by weight of iodine based upon the weight of polydextrose polymer utilized. The various other adjuvants may also be dissolved in the polar solvent during formation of the PDI complex, adjuvants such as the buffer, surfactant, glycerine, etc. After all the requisite components have been incorporated into solution, and the solution adequately stirred for a sufficient period of time such as 30 minutes, then the solution may be cooled if necessary, optionally filtered, and freeze-dried to prepare crystals or powders of the PDI iodophor complex. The iodine may be incorporated into the polydextrose solution in any number of ways, such as by simultaneous addition of an alkali metal iodide solution, followed by hydriodic acid addition in a small amount. After the solution has been suitably prepared and freeze-dried, the complex may be assayed for available iodine. The iodophor preparation may also be assayed for available iodine content after a certain period of time, e.g. several weeks, to make certain that the effectiveness of the preparation does not dissipate over time. Other suitable polar solvents that may be used for the preparation of the iodophor complex include alcohol, in addition to the water, and any mixture of these. Polydextrose iodine powder is very water-soluble at room temperature. Such a solution has a reddish-brown color. Iodine availability in the aqueous solution of the iodophor, may be determined by direct titration with standardized sodium thiosulfate solution. This is a classic oxidation-reduction type reaction conventionally used in iodine chemistry. For example, polydextrose iodine complex (PDI iodophor) with a 7.45% available iodine content, exhibits a solubility of about 81% in water. A polydextrose iodine complex with 3.25% available iodine, also exhibits a solubility of about 81% in water. Melting points of various polydextrose-iodine complexes have also been determined. Such samples have been previously dried under vacuum and over P 2 O 5 for 16 hours. The results of melting point determinations for the various samples were as follows: ______________________________________ MELTING POINTSAMPLE (°C.) OBSERVATIONS______________________________________7.45% available iodine 97-127 Melts into a dark red liquid.3.25% available iodine 93-127 Melts into a red liquid.Polydextrose alone 115-130 Melts into a clear liquid.______________________________________ The polydextrose-iodine complexes exhibit an increased temperature range over which melting begins and ends. The melting point is also slightly depressed, as compared with the polydextrose control alone. Such melting point determination was carried out in a Thomas Hoover Capillary Melting Point Apparatus. The melting point of elemental iodine itself, is 113.6° C. In the preparation of iodophors in general, several factors affect the quality and efficacy of the preparations. For example, the amount of iodide ion present in solution critically affects the overall stability of the iodophor preparation. Rate of the decomposition of elemental iodine in solution is inversely proportional to the iodide ion concentration. Moreover, an increase in pH of the preparation reduces the overall stability of the iodophor, while the increase in iodide ion content has the reverse effect, in other words increases stability of the iodophor. Furthermore, the strength of the bond formed between the elemental iodine and the polydextrose or Ficoll polymer or the matrix thereof, plays a critical roll in determining the velocity of liberation of iodine from the polymer depot or the matrix thereof, to the receptor site. Various iodophor preparations, namely polydextrose iodine complex (PDI) and polyvinylpyrrolidone iodine complex (PVP-I) were prepared using the respective polymers polydextrose and polyvinylpyrrolidone (PVP-K30), with elemental iodine or Lugol's Solution. Polyvinylpyrrolidone PVP-K30 is a comparatively high molecular weight polymer with at least 95% thereof having a weight average molecular weight of 40,000. This particular polymer, when reacted with iodine, results in the complex of polyvinylpyrrolidone iodine as noted supra. This particular complex is soluble in water and when applied to a wound, acts as an antibacterial agent. The rate and velocity of release of iodine from the polymer depot is determined by the strength of the bond between the iodine and the polymer, and also by the pH of the formulation. Several such formulations with varied strength of available iodine were prepared with the respective polydextrose iodine (PDI) and polyvinylpyrrolidone iodine (PVP-I) complexes, with antibacterial activity thereof being compared using various microorganisms. Four such formulations using PDI, surfactant, glycerin, and buffer, were prepared at pH of about 5. The available iodine content in these preparations varied from 2.0%, 1.0%, 0.25%, to 0.1%. Additionally, four samples were prepared using only the buffer adjuvant, having the same strength of available iodine as the initial four preparations and a pH of also about 5. Additionally, four formulations of polyvinylpyrrolidone iodine (PVP-I) complex were also prepared, using the PVP-I, surfactant, glycerin, and buffer, also at a pH of about 5. Available iodine content in the PVP-I preparations also vary from 2.0%, 1.0%, 0.25%, to 0.1%. Also, four additional samples were prepared using only the buffer, with the same requisite strengths of available iodine and pH of about 5. The following microorganisms were used for antibacterial evaluation: Staphylococcus aureus #1 (ATCC 6538) penicillin sensitive Staphylococcus aureus #4 (GBL) penicillin resistant Staphylococcus aureus #30 (GBL-CDC) toxic shock strain Staphylococcus epidermidids (GBL) normal skin flora Spores of B. Pumilus E601. The application of the respective iodophor preparations upon the concomitant bacteria samples was carried out. The specific compositions that were examined in the testing were as follows: PDI COMPLEX 2.0% AVAILABLE I 2 27.78 g PDI Complex 30.0 g Glycerin 0.25 g Alipal CO-436 1.119 g Buffer Water to 100 cc PDI COMPLEX WITH 1% AVAILABLE I 2 13.89 g Polydextrose Iodine 30.0 g Glycerin 0.25 g Alipal CO-436 0.56 g Buffer Water to 100 cc PDI COMPLEX WITH 0.25% AVAILABLE I 2 3.47 g Polydextrose Iodine 30.00 g Glycerin 0.25 g Alipal CO-436 0.140 g Buffer Water to 100 cc PDI COMPLEX WITH 0.1% AVAILABLE I 2 1.38 g Polydextrose Iodine 30.00 g Glycerin 00.25 g Alipal CO-436 0.056 Buffer Water to 100 cc PVPI COMPLEX WITH 2.0% AVAILABLE I 2 20.0 g PVPI 30.0 g Glycerin 0.25 g Alipal CO-436 4.18 g Buffer Water to 100 cc PVPI COMPLEX WITH 1% AVAILABLE I 2 10.31 g PVPI 30.0 g Glycerin 0.25 g Alipal CO-436 2.09 g Buffer Water to 100 cc PVPI COMPLEX WITH 0.25% AVAILABLE I 2 2.58 g PVPI 30.0 g Glycerin 0.25 g Alipal CO-436 0.523 g Buffer Water to 100 cc PVPI COMPLEX WITH 0.1% AVAILABLE I 2 1.031 g PVPI 30.0 g Glycerin 00.25 g Alipal CO-436 0.209 g Buffer Water to 100 cc The results of the tests conducted as set forth in the following tables: TABLE 1__________________________________________________________________________Comparison of Polydextrose Iodine Complex withPolyvinylpyrrolidone Iodine Complex with regards to Killing TimeS. aureus #1, Penicillin Sensitive (1 min.) D-10 15 sec. 30 sec. 1 min. value Result__________________________________________________________________________*PDI Complex 2.0% Av. I.sub.2 <10 <10 <10 <15 complete killPDI Complex 1.0% Av. I.sub.2 <10 <10 <10 <15 complete killPDI Complex 0.25% Av. I.sub.2 <10 <10 <10 <15 complete killPDI Complex 0.1% Av. I.sub.2 <10 <10 <10 <15 slower kill**PVPI Complex 2.0% Av. I.sub.2 7. × 10.sup.3 3.0 × 10.sup.4 3.4 × 10.sup.4 97 sec slower kill (3.85) (4.48) (4.53)PVPI Complex 1.0% Av. I.sub.2 <10 <10 <10 <15 complete killPVPI Complex 0.25% Av. I.sub.2 <10 <10 <10 <15 complete killPVPI Complex 0.1% Av. I.sub.2 <10 <10 <10 <15 complete killPDI Complex 2.0% Av. I.sub.2 1.2 × 10.sup.3 8.9 × 10.sup.2 1.1 × 10.sup.3 28 sec. slow kill (3.08) (2.95) (3.04)PDI Complex 1.0% Av. I.sub.2 <10 <10 <10 <15 complete killPDI Complex 0.25% Av. I.sub.2 <10 <10 <10 <15 complete killPDI Complex 0.1% Av. I.sub.2 <10 <10 <10 <15 complete killPVPI Complex 2.01% Av. I.sub.2 <10 <10 <10 <15 complete killPVPI Complex 1.1% Av. I.sub.2 360 210 160 20 sec slower kill (2.56) (2.32) (2.20)PVPI Complex 0.25% Av. I.sub.2 <10 <10 <10 <15 complete killPVPI Complex 0.1% Av. I.sub.2 <10 <10 <10 <15 complete kill__________________________________________________________________________MATCHED PAIR ANALYSIS(A) PDI Complex 2.0% Av. I.sub.2 > PVPI Complex 2.0% Av. I.sub.2(B) PDI Complex 1.0% Av. I.sub.2 = PVPI Complex 1.0% Av. I.sub.2(C) PDI Complex 0.25% Av. I.sub.2 = PVPI Complex 0.25% Av. I.sub.2(D) PDI Complex 0.1% Av. I.sub.2 = PVPI Complex 0.1% Av. I.sub.2(E) PDI Complex 2.0% Av. I.sub.2 < PVPI Complex 2.0% Av. I.sub.2(F) PDI Complex 1.0% Av. I.sub.2 > PVPI Complex 1.0% Av. I.sub.2(G) PDI Complex 0.25% Av. I.sub.2 = PVPI Complex 0.25% Av. I.sub.2(H) PDI Complex 0.1% Av. I.sub.2 = PVPI Complex 0.1% Av. I.sub.2__________________________________________________________________________CONCLUSION: In samples killed rapidly with D.sub.10 -values in most cases being <15 seconds, except for: PVPI Complex 2.0% Av. I.sub.2 slower kill PDI Complex 2.0% Av. I.sub.2 relatively PVPI Complex 1.0% Av. I.sub.2 PVPI Complex 2.0% Av. I.sub.2 was least active__________________________________________________________________________ *POLYDEXTROSE IODINE COMPLEX **Polyvinyl pyrrolidone Iodine Complex TABLE 2__________________________________________________________________________Comparison of Polydextrose - Iodine Complexwith Polyvinylpyrrolidone - Iodine complex with regard to killing timeS. aureus #4, Penicillin Resistant 15 sec. 30 sec. 1 min. value result__________________________________________________________________________PDI Complex 2.0% Av. I.sub.2 <10 <10 <10 <15 complete killPDI Complex 1.0% Av. I.sub.2 <10 <10 <10 <15 complete killPDI Complex 0.25% Av. I.sub.2 <10 <10 <10 <15 complete killPDI Complex 0.1% Av. I.sub.2 <10 <10 <10 <15 complete killPVPI Complex 2.0% Av. I.sub.2 1.0 × 10.sup.5 1.8 × 10.sup.4 6.0 × 10.sup.3 46 sec. slower kill (5.0) (4.26) (3.78)PVPI Complex 1.0% Av. I.sub.2 <10 <10 <10 <15 complete killPVPI Complex 0.25% Av. I.sub.2 <10 <10 <10 <15 complete killPVPI Complex 0.1% Av. I.sub.2 <10 <10 <10 <15 complete killPDI Complex 2.0% Av. I.sub.2 730 730 530 25 sec. slower kill (2.86) (2.86) (2.72)PDI Complex 1.0% Av. I.sub.2 <10 <10 <10 <15 complete killPDI Complex 0.25% Av. I.sub.2 <10 <10 <10 <15 complete killPDI Complex 0.1% Av. I.sub.2 <10 <10 <10 <15 complete killPVPI Complex 2.0% Av. I.sub.2 6.0 × 10.sup.4 50 <10 12 sec. complete kill (3.78) (1.70)PVPI Complex 1.0% Av. I.sub.2 550 260 330 23 sec. slower kill (2.74) (2.41) (2.52)PVPI Complex 0.25% Av. I.sub.2 2.9 × 10.sup.4 150 10 24 sec. slower kill (4.46) (2.18)PVPI Complex 0.1% Av. I.sub.2 <10 <10 <10 <15 complete kill__________________________________________________________________________MATCHED PAIR ANALYSIS(A) PDI Complex 2.0% Av. I.sub.2 > PVPI Complex 2.0% Av. I.sub.2(B) PDI Complex 1.0% Av. I.sub.2 = PVPI Complex 1.0% Av. I.sub.2(C) PDI Complex 0.25% Av. I.sub.2 = PVPI Complex 0.25% Av. I.sub.2(D) PDI Complex 0.1% Av. I.sub.2 = PVPI Complex 0.1% Av. I.sub.2(E) PDI Complex 2.0% Av. I.sub.2 < PVPI Complex 2.0% Av. I.sub.2(F) PDI Complex 1.0% Av. I.sub.2 > PVPI Complex 1.0% Av. I.sub.2(G) PDI Complex 0.25% Av. I.sub.2 = PVPI Complex 0.25% Av. I.sub.2(H) PDI Complex 0.1% Av. I.sub.2 = PVPI Complex 0.1% Av. I.sub.2__________________________________________________________________________CONCLUSION: In samples killed rapidly with D.sub.10 -values in most cases being <15 seconds, except for: PVPI Complex 2.0% Av. I.sub.2 slower kill PDI Complex 2.0 Av. I.sub.2 relatively PVPI Complex 1.0% Av. I.sub.2 PVPI Complex 2.0% Av. I.sub.2 was least active__________________________________________________________________________ TABLE 3__________________________________________________________________________Comparison of Polydextrose - Iodine Complex withPolyvinylpyrrolidone - Iodine Complex with regard to killing timeS. aureus #30 Toxic Shock Strain (1 min.) D-10 15 sec. 30 sec. 1 min. value Result__________________________________________________________________________PDI Complex 2.0% Av. I.sub.2 <10 <10 <10 <15 complete killPDI Complex 1.0% Av. I.sub.2 <10 <10 <10 <15 complete killPDI Complex 0.25% Av. I.sub.2 <10 <10 <10 <15 complete killPDI Complex 0.1% Av. I.sub.2 <10 <10 <10 <15 complete killPVPI Complex 2.0% Av. I.sub.2 1.0 × 10.sup.5 5.0 × 10.sup.4 4.3 × 10.sup.4 49 sec. slower kill (5.0) (4.70) (4.63)PVPI Complex 1.0% Av. I.sub.2 <10 <10 <10 <15 complete killPVPI Complex 0.25% Av. I.sub.2 30 <10 <10 3 sec. complete kill (1.48)PVPI Complex 0.1% Av. I.sub.2 190 <10 <10 49 sec. complete kill (2.28)PDI Complex 2.0% Av. I.sub.2 880 740 540 19 sec. slower kill (2.94) (2.87) (2.73)PDI Complex 1.0% Av. I.sub.2 <10 <10 <10 <15 complete killPDI Complex 0.25% Av. I.sub.2 <10 <10 <10 <15 complete killPDI Complex 0.1% Av. I.sub.2 <10 <10 <10 <15 complete killPVPI Complex 2.0% Av. I.sub.2 7.0 × 10.sup.4 6.1 × 10.sup.2 1.3 × 10.sup.2 16 sec. slower kill (4.85) (2.79) (2.11)PVPI Complex 1.0% Av. I.sub.2 4.9 × 10.sup.4 290 320 18 sec. slower kill (4.69) (2.46) (2.51)PVPI Complex 0.25% Av. I.sub.2 8.5 × 10.sup.3 <10 <10 8 sec. slower kill (3.93)__________________________________________________________________________MATCHED PAIR ANALYSIS(A) PDI Complex 2.0% Av. I.sub.2 > PVPI Complex 2.0% Av. I.sub.2(B) PDI Complex 1.0% Av. I.sub.2 = PVPI Complex 1.0% Av. I.sub.2(C) PDI Complex 0.25% Av. I.sub.2 > PVPI Complex 0.25% Av. I.sub.2(D) PDI Complex 0.1% Av. I.sub.2 > PVPI Complex 0.1% Av. I.sub.2(E) PDI Complex 2.0% Av. I.sub.2 = PVPI Complex 2.0% Av. I.sub.2(F) PDI Complex 1.0% Av. I.sub.2 > PVPI Complex 1.0% Av. I.sub.2(G) PDI Complex 0.25% Av. I.sub.2 > PVPI Complex 0.25% Av. I.sub.2(H) PDI Complex 0.1% Av. I.sub.2 > PVPI Complex 0.1% Av. I.sub.2__________________________________________________________________________CONCLUSION: In samples killed rapidly with D.sub.10 -values in most cases being <15 seconds, except for: PVPI Complex 2.0% Av. I.sub.2 slower kill PDI Complex 2.0 Av. I.sub.2 relatively PVPI Complex 2.0% Av. I.sub.2 PVPI Complex 1.0% Av. I.sub.2 PVPI Complex 0.25% Av. I.sub.2 PVPI Complex 0.1% Av. I.sub.2 PVPI Complex 2.0% Av. I.sub.2 was least active__________________________________________________________________________ TABLE 4__________________________________________________________________________Comparison of Polydextrose - Iodine Complex withPolyvinylpyrrolidone - Iodine Complex with regard to killing timeS. epidermidis Normal Skin Flora (1 min.) D-10 15 sec. 30 sec. 1 min. value Result__________________________________________________________________________PDI Complex 2.0% Av. I.sub.2 <10 <10 <10 <15 complete killPDI Complex 1.0% Av. I.sub.2 <10 <10 <10 <15 complete killPDI Complex 0.25% Av. I.sub.2 8.3 × 10.sup.3 <10 <10 <13 complete kill (3.92)PDI Complex 0.1% Av. I.sub.2 <10 <10 <10 <15 complete killPVPI Complex 2.0% Av. I.sub.2 3.5 × 10.sup.3 3.4 × 10.sup.3 6.7 × 10.sup.2 27 sec. slower kill (3.54) (3.53) (2.82)PVPI Complex 1.0% Av. I.sub.2 <10 <10 <10 <15 complete killPVPI Complex 0.25% Av. I.sub.2 140 <10 <10 <15 complete kill (2.15)PVPI Complex 0.1% Av. I.sub.2 <10 <10 <10 <15 complete killPDI Complex 2.0% Av. I.sub.2 440 400 490 26 sec. slower kill (2.64) (2.60) (2.69)PDI Complex 1.0% Av. I.sub.2 <10 <10 <10 <15 complete killPDI Complex 0.25% Av. I.sub.2 <10 <10 <10 <15 complete killPDI Complex 0.1% Av. I.sub.2 <10 <10 <10 <15 complete killPDI Complex 2.0% Av. I.sub.2 200 <10 <10 5 sec. complete killPVPI Complex 1.0% Av. I.sub.2 410 <10 <10 6 sec. complete kill (2.61)PVPI Complex 0.25% Av. I.sub.2 1.1 × 10.sup.3 <10 <10 6 sec. complete kill (3.04)PVPI Complex 0.1% Av. I.sub.2 <10 <10 <10 8 sec. slower kill__________________________________________________________________________MATCHED PAIR ANALYSIS(A) PDI Complex 2.0% Av. I.sub.2 > PVPI Complex 2.0% Av. I.sub.2(B) PDI Complex 1.0% Av. I.sub.2 = PVPI Complex 1.0% Av. I.sub.2(C) PDI Complex 0.25% Av. I.sub.2 < PVPI Complex 0.25% Av. I.sub.2(D) PDI Complex 0.1% Av. I.sub.2 = PVPI Complex 0.1% Av. I.sub.2(E) PDI Complex 2.0% Av. I.sub.2 < PVPI Complex 2.0% Av. I.sub.2(F) PDI Complex 1.0% Av. I.sub.2 > PVPI Complex 1.0% Av. I.sub.2(G) PDI Complex 0.25% Av. I.sub.2 > PVPI Complex 0.25% Av. I.sub.2(H) PDI Complex 0.1% Av. I.sub.2 = PVPI Complex 0.1% Av. I.sub.2__________________________________________________________________________CONCLUSION: In samples killed rapidly with D.sub.10 -values in most cases being <15 seconds, except for: PVPI Complex 2.0% Av. I.sub.2 slower kill PDI Complex 2.0 Av. I.sub.2 relatively__________________________________________________________________________ TABLE 5__________________________________________________________________________Comparison of Polydextrose - Iodine complex with Polyvinylpyrrolidone -Iodinecomplex with regards to killing timeDry Formulations, Staphylococcicidal ActivityRankings of Activity calc. at 15 or D.sub.10 -value (in seconds to kill 1-log) 60 sec. S. aureus #1 S. aureus #4 S. aureus #30 S. epid.__________________________________________________________________________PDI Complex 2.0% Av. I.sub.2 <15 <15 <15 <15PDI Complex 1.0% Av. I.sub.2 <15 <15 <15 <15PDI Complex 0.25% Av. I.sub.2 <15 <15 <15 13PDI Complex 0.1% Av. I.sub.2 <15 <15 <15 <15PVPI Complex 2.0% Av. I.sub.2 97 46 49 27PVPI Complex 1.0% Av. I.sub.2 <15 <15 <15 <15PVPI Complex 0.25% Av. I.sub.2 <15 <15 3 <15PVPI Complex 0.1% Av. I.sub.2 <15 <15 4 <15PDI Complex 2.0% Av. I.sub.2 28 25 19 26PDI Complex 1.0% Av. I.sub.2 <15 <15 <15 <15PDI Complex 0.25% Av. I.sub.2 <15 <15 <15 <15PDI Complex 0.1% Av. I.sub.2 <15 <15 <15 <15PVP Complex 2.0% Av. I.sub.2 <15 12 16 5PVP Complex 1.0% Av. I.sub.2 20 23 18 6PVP Complex 0.25% Av. I.sub.2 <15 24 8 8PVP Complex 0.1% Av. I.sub.2 <15 <15 6 <1515 seconds incomplete kill (a) 3/16 (b) 5/16 (c) 8/16 (d) 6/16__________________________________________________________________________LABORATORY REPORTNOTE:<15 seconds indicates no colonies counted at the 10.sup.-1 dilutionat 15 seconds exposure and, thus, a count of <10 survivors/mlSuch a value could be as low as 1 second (i.e. <15 sec = completekill for this test sensitivity limits) (a) S. aureus #1 was themost sensitive strain with only 3/16 showing incomplete kill at15 sec. (b) 5/6 (d) 6/16 (c) S. aureus (toxic shock) was the mostresistant strain in this series with as many as 8/16 with survivorsat 15 seconds.__________________________________________________________________________OVER-ALL CONCLUSIONS Matched Pair Analyses show differences and equivalences, as seen in tables 1-4. PDI Complex 0.1% Av. I.sub.2 was the least active. PVPI 2.0% Av. I.sub.2 PDI Complex 2.0% Av. I.sub.2 PVPI Complex 2.0% Av. I.sub.2 also showed diminished PVPI Complex 1.0% Av. I.sub.2 15 second kills. PVPI Complex 0.25% Av. I.sub.2__________________________________________________________________________ TABLE 6__________________________________________________________________________Comparison of Polydextrose - Iodine Complexwith Polyvinylpyrrolidone - Iodine complex with regard to killing timeB. pumilus sporesGBL no. 24760/15-30 1 hr. 3 hrs 6 hrs. 24 hrs D.sub.10__________________________________________________________________________PDI Complex 2.0% Av. I.sub.2 850 10 <10 <10PDI Complex 1.0% Av. I.sub.2 1.2 × 10.sup.3 <10 <10 <10PDI Complex 0.25% Av. I.sub.2 100 <10 <10 <10PDI Complex 0.1% Av. I.sub.2 950 <10 <10 <10PDI Complex 2.0% Av. I.sub.2 6.8 × 10.sup.5 9.6 × 10.sup.5 4.2 × 10.sup.5 2.6 > 10.sup.4 inactivePVPI Complex 1.0% Av. I.sub.2 1.4 × 10.sup.5 9.1 × 10.sup.4 1.2 × 10.sup.4 7.0 × 10.sup.3 inactivePVPI Complex 0.25% Av. I.sub.2 8.6 × 10.sup.4 1.1 × 10.sup.3 1.4 × 10.sup.4 660PVPI Complex 0.1% Av. I.sub.2 1.6 × 10.sup.6 4.9 × 10.sup.5 8.3 × 10.sup.4 50PDI Complex 2.0% Av. I.sub.2 10 <10 <10 <10PDI Complex 1.0% Av. I.sub.2 <10 <10 <10 <10PDI Complex 0.25% Av. I.sub.2 <10 <10 <10 <10PDI Complex 0.1% Av. I.sub.2 120 <10 <10 <10PVP Complex 2.0% Av. I.sub.2 7.9 × 10.sup.5 6.2 × 10.sup.5 1.6 × 10.sup.4 240PVP Complex 1.0% Av. I.sub.2 8.0 × 10.sup.5 1.7 × 10.sup.3 7.0 × 10.sup.3 30PVP Complex 0.25% Av. I.sub.2 3.5 × 10.sup.5 6.3 × 10.sup.4 7.3 × 10.sup.2 <10PVP Complex 0.1% Av. I.sub.2 1.7 × 10.sup.5 8.9 × 10.sup.4 70 <10__________________________________________________________________________Paired Rankings(A) PDI Complex 2.0% Av. I.sub.2 > PVPI Complex 2.0% Av. I.sub.2(B) PDI Complex 1.0% Av. I.sub.2 > PVPI Complex 1.0% Av. I.sub.2(C) PDI Complex 0.25% Av. I.sub.2 > PVPI Complex 0.25% Av. I.sub.2(D) PDI Complex 0.1% Av. I.sub.2 > PVPI Complex 0.1% Av. I.sub.2(E) PDI Complex 2.0% Av. I.sub.2 > PVPI Complex 2.0% Av. I.sub.2(F) PDI Complex 1.0% Av. I.sub.2 > PVPI Complex 1.0% Av. I.sub.2(G) PDI Complex 0.25% Av. I.sub.2 > PVPI Complex 0.25% Av. I.sub.2(H) PDI Complex 0.1% Av. I.sub.2 > PVPI Complex 0.1% Av. I.sub.2__________________________________________________________________________BEST FORMULATIONS FOR ALL COCCI AND SPORES PDI Complex 1.0% Av. I.sub.2 PDI Complex 0.25% Av. I.sub.2__________________________________________________________________________ According to the results of the test conducted as outlined above, the polydextrose iodine complexes (PDI) with 2%, 1%, 0.25%, and 0.1% available iodine content, were found to be more potent than the polyvinylpyrrolidone iodine (PVPI) complexes having the same respective percentages of available iodine content. The polydextrose iodine complexes having only the buffer with 1% and 0.2% available iodine content, were found to be the best formulations for all cocci and spores, whereas the polyvinylpyrrolidone iodine formulations with 2% available iodine, were found to be the least active. Thus it is quite clear that the polydextrose iodine iodophor complexes of the present invention provide distinct antibacterial and germicidal benefits, with improved performance over the previously-used polyvinylpyrrolidone iodine (PVPI) iodophor complexes. The viscosity of a polydextrose-iodine (PDI) iodophor complex has also been analyzed, as opposed to viscosity of just polydextrose solutions alone. PDI iodophor solutions have been prepared containing respective amounts of 50% weight/volume, 40% weight/volume, 30% weight/volume, 20% weight/volume, 8% weight/volume, 5% weight/volume, and 1% weight/volume of iodine therein. These respective solutions are filtered through 0.45 micron filters. Relative viscosities are measured using Ubbelohde glass capillary viscometers, with size 0B for 50-20% solutions, and size 0C for 10-1% solutions. The relative viscosity at 25° C.±0.05° C., is measured as a ratio of flow times for the sample solutions, over the flow time of pure water. The moisture content of the polydextrose-iodine (PDI) complex is determined by the Karl-Fischer titration method, to be 11.28%. Available iodine has been determined to be 7.45% and the iodide concentration has been determined as 6.745% KI. The overall content of polydextrose and the polydextrose-iodine complex (PDI) is therefore 74.52% by weight. The viscosities of the respective polydextrose-iodine complexes, and the polydextrose control, were determined. It was found that polydextrose-iodine complexes exhibit a higher degree of viscosity than solutions of polydextrose alone, at equivalent polydextrose concentrations. The resulting estimate of intrinsic viscosity, (n), is also greater for polydextrose-iodine complexes, than for polydextrose solutions alone. This indicates that the polydextrose molecule is slightly expanded when in solution of the polydextrose-iodine complexes, as would be expected with inclusion of iodine or iodide in the formation of the requisite polymer matrix in the iodophor. The specific resistance or equivalent conductance of the PDI iodophores, has also been compared with the PVP-I iodophores. Specific electrical resistance of a solution is defined as conductance per unit cross-sectional area per centimeter. For analysis of the equivalent conductance, the polydextrose iodine and polyvinylpyrrolidone iodine complexes were prepared as follows, in addition to preparation of iodine solution, and iodine control solution. The iodine solution itself was prepared by dissolving 100 g of potassium iodide (KI) in 150-200 cc of water. 50.0 g of elemental iodine, I 2 , was added with stirring to this solution, which was then raised to 500 ml in volume, by the further addition of water. The iodine control solution was prepared by diluting 5 cc of iodine solution in a volumetric flask, followed by stirring for one hour at room temperature, and allowing the same to stand overnight. The polydextrose-iodine complex was prepared by dissolving 10.0 g polydextrose in 70 cc of water, with 5 cc of iodine stock solution being added with stirring thereto. The solution was then raised to the volume of a 100 cc volumetric flask, by addition of water therein, followed by stirring for one hour at room temperature, and allowing the same to stand overnight. The polyvinylpyrrolidone-iodine complex (PVP-I) was prepared by dissolving 10.0 g of PVP-K30 in 60 cc of water. 5 cc of iodine solution was dissolved in 25 cc of water, with the resulting iodine solution was slowly added to the PVP solution with rapid stirring. This solution thus formed was stirred at room temperature until all gelatinous material was dissolved, stirring being carried on for up to one-half hour. The resulting solution was raised to a volume of 100 cc, and stirred for the remainder of the hour, followed by standing overnight. Each of the above four prepared solutions was assayed before analysis for available iodine content, using 0.02N thiosulfate, and assayed for total iodides (I 2 +I - ), using potentiometric titration with 0.1N silver nitrate. Similarly, solutions of PVP and polydextrose alone, containing respective amounts of 8.0 g/l polymer, were prepared by dissolving 0.8 g of respective polymer in 70 cc water, to bring the resulting solutions to the requisite volume levels as the other solutions so prepared. A 0.5M potassium chloride (KCl) solution was also prepared at the concomitant volume. Conductance and capacitance of each of the above seven solutions prepared, were analyzed for the various concentrations thereof, using the General Radio Capacitance Measuring Assembly. Experimental solutions of the iodine control solution, the polydextrose-iodine complex, the PVP-I complex, and solutions of PVP alone and polydextrose alone, were diluted to concentrations of 2 ml/100, 1 ml/100, 0.1 ml/50, 0.1 ml/100 for iodine containing solutions, and to concentrations of 20 ml/100, 100 ml/100, 2 ml/100, and 1 ml/100 for the polydextrose or PVP solutions alone. The parallel conductance and capacitance were read directly from the general radio capacitance measuring instrument, using a model CEL3-J-1 cell. The potassium chloride (KCl) solution was measured at concentrations of 0.01M, 0.005M, 0.001M, 0.00005M, and 0.0001M respectively. The tests confirmed that as the concentration of PVP in solution increases, the equivalent conductance decreases. However, if the concentration of PVP decreases, then the equivalent conductance increases exponentially. In the case of polydextrose, with an equivalent conductance of 0.018 ohm -1 cm -3 , as the concentration of polydextrose increases, the equivalent conductance decreases linearly. This tends to substantiate that polydextrose ionizes less than polyvinylpyrrolidone. In the case of iodine solution (Lugol's Solution), as the concentration increases, equivalent conductance decreases. Concerning the polydextrose-iodine iodophor complex (PDI), as concentration increases, conductance decreases. However, if concentration decreases, i.e. is diluted, conductance increases linearly. Thi substantiates that the degree of binding remains substantially constant with dilution of PDI complexes, due to the binding of tri-iodide and/or iodide to the polydextrose. The contribution of equivalent conductance by the polydextrose is about 10% at zero concentration. The equivalent conductance for PDI is 160.4 ohm -1 cm -3 . This is far lower than the equivalent conductance for PVPI (216.8 ohm -1 cm -3 ), and also for the equivalent conductance of the iodine solution (222.7 ohm -1 cm -3 ). This tends to confirm the binding of I -3 and/or I - to the polydextrose in the PDI iodophors. The higher the equivalent conductance number in the PDI iodophor, the higher the free ion concentration and the less binding to the polydextrose polymer. In the case of PVP iodophor, the data substantiates that there is some binding of I -3 and/or I - to the PVP, but less than in the PDI iodophor. There is no binding occurring at all in the iodine solution itself, since the iodine is completely ionized in solution. In the PVPI complex, the equivalent conductance bears a linear relationship to the square root of the total ion concentration, the equivalent conductance increasing with concentration. Relative to the iodine solution, polydextrose iodine complex (PDI) exhibits a much lower value of equivalent conductance, and the additivity rule does not hold in this instance in the range of zero concentration. Neglecting the contribution of polydextrose to the conductivity, since it is negligible, the decrease in zero concentration equivalent conductivity must be due to a decrease in the free ion concentration, implying complexing of ions by the polydextrose. However, a reversible equilibrium does not give rise to a linear curve in the square root of total ion concentration, and in the rate of zero concentration, the equivalent conductivity of PDI should approach that of iodine solution alone, as the equilibrium shifts towards complete dissociation. This implies a "irreversible" binding process (no covalent interation occurs because titration assays exhibit no loss of ions by chemical interaction). Concerning the polyvinylpyrrolidone-iodine complex, PVP itself exhibits some loss of total ions, but no loss of available iodine, indicating the possibility of a small degree of covalent interaction with the iodine. However, the zero concentration equivalent conductivity is only slightly less than that for iodine solution alone, indicating little or no binding of I - or I -3 by the PVP. Therefore, it is quite clearly observed that on the basis of this data noted above, polydextrose is definitely complexed with tri-iodide (I -3 ) and/or iodide (I - ), because the equivalent conductance at zero concentration is significantly less than that for iodine solution alone (e.g., Lugol's Solution). The ratio of free ions to bound ions in PDI is constant, even as the concentration decreases. Thus, PDI exhibits lower free ion concentration than iodine solution. This is possibly due to the hydrogen bonding or osmotic equilibrium that is involved. The lower equivalent conductance of PDI tends to indicate bonding I -3 and/or I - to the polydextrose. Regarding PVPI, it is possible that the iodine may be enclosed in the helical polymer matrix. This data seems to confirm that there is not much binding of I -3 and/or I - to the PVP. It appears that contribution by PVP to equivalent conductance of polyvinylpyrrolidone iodine, is about ten times greater than the contribution of polydextrose to the PDI complex. Absorbance tests indicate complexing of the iodine by the polydextrose and polyvinylpyrrolidone. The rate of release of iodine from polydextrose iodine iodophor is intermediate between the rate of release for polyvinylpyrrolidone iodine and for just iodine solution alone. In other words, the results show a decreasing rate of release from iodine solution, to polydextrose iodine, to polyvinylpyrrolidone iodine. Equilibrium iodine concentration was determined for the polydextrose-iodine iodophor complexes having the respective concentrations of 7.45% and 3.25% available iodine, with these equilibrium iodine determinations being compared with values obtained fo the polyvinylpyrrolidone iodine (PVP-I) complex having 9.6% available iodine, and for the iodine solution alone. The amount of solution containing 1.0 g. iodine was calculated for each of these respective solutions. Then, this amount of solution from each of the respective solutions noted above, was dissolved in 80 ml. water, with water being added to raise the volume thereof to 100 ml in a 100 ml volumetric flask. The resulting solution from each of the respective compositions was then used to determine the equilibrium iodine concentration. For each of the four samples so prepared, four ratios of aqueous solution to heptane were used for the extractions that were carried out: 3 aqueous:1 heptane, 2 aqueous:1 heptane, 1 aqueous:1 heptane, and 0.5 aqueous:1 heptane. The aqueous solution and heptane were pipetted into a 20 ml. centrifuge tube, shaken for one minute, and then centrifuged at 2,000 rpm for 2 minutes. Ambient temperature was noted. Then, absorbance of iodine into the organic heptane layer at 522.6 nm was measured and converted into ppm iodine in the aqueous phase according to the following formula: ##STR4## The calculations were made for each of the four samples so prepared with the heptane and the results being plotted on a graph. The results as determined from the extraction were as follows: ______________________________________ Equilibrium Iodine______________________________________PDI, 7.45% Available I.sub.2 103.3 ppmIodine Solution Alone 141.7 ppmPVP-I Complex 1.01 ppm______________________________________ The data clearly confirms that the amount of equilibrium iodine released from polydextrose iodine iodophor (PDI) is far less than from iodine solution, due to the complexing of iodine with the polydextrose. When compared with the well-know PVPI iodophor, the amount of equilibrium iodine released from PDI is far greater than from PVPI, thus providing a greater germicidal and antiseptic effect. The percent of available iodine in an aqueous polydextrose iodine antiseptic iodophor composition, may vary from 0.01% to 20% based on the overall weight of the particular composition or solution. The ultraviolet/visual absorbance scan of the polydextrose iodine complex having 7.45% available iodine content, was determined and compared with the scan for polydextrose solution alone. An aqueous solution of the polydextrose-iodine complex noted above was prepared to contain 0.004% available iodine by weight/volume of solution. An ultraviolet/visual absorbance scan from 600-190 nm was taken. Similarly, a solution of polydextrose was prepared to contain an approximate equivalent concentration of polydextrose alone (0.06% polydextrose weight/volume of solution). An ultraviolet/visual scan from 600 nm-190 nm was also taken for this polydextrose solution alone. The results were as follows: ______________________________________ Peak Maxima______________________________________PDI 351.5 nm, 287.5 nm, 223 nm, 209 nmPolydextrose Solution Alone 281 nm, 192 nm, shoulder at 221 nm______________________________________ These results demonstrate a significant difference between the PDI complex and the polydextrose solution alone, especially in the absence of absorbance peaks at 351 nm and 209 nm for the polydextrose solutions alone. There is the presence of absorbant peaks at 351 nm and 209 nm in the PDI solution, whereas there is none in the corresponding polydextrose solution alone. At the same time, the PDI solution shows no absorbance at 192 nm, a strong absorbance at 287.5 nm, and a strong absorbance at 223 nm, as opposed to a weak absorbance at 281 nm and a weak shoulder at 221 nm for the polydextrose solution alone. The peaks occurring in the PDI solution at 351.5 nm and 223 nm correspond to the absorbance of I 3 - and I - respectively, indicating the presence of tri-iodide and iodide ions within the PDI complex. The infrared spectra of the respective polydextrose-iodine complexes having 7.45% available iodine and 3.25% available iodine respective, were taken using a potassium bromide (KBr) pellet. Scans were taken over the range of 4,000 cm -1 to 200 cm -1 . Both scans were extremely similar to the infrared scan of polydextrose solution alone. Slight differences occurred in the region of 1,500 cm -1 to 1,200 cm -1 . A very slight shoulder appears in the PDI scans, while increased intensity of the peak at 800 to 300 cm -1 has been observed. The present invention will be explained in further detail by way of the following specific examples, which are not to be construed as limiting the scope of the present invention in any way. EXAMPLE 1 25 ml of iodine solution containing 629.2 mg I 2 /ml (total amount of iodine present in the solution equal to 15.73 g) was freeze dried, with the weight of the freeze-dried sample being determined as 10.3 g. The total amount of iodine found in the sample was 0.123 g, with a loss of iodine equal to 99.3%. When this iodine solution was reacted with polydextrose polymer solution followed by freeze drying, the loss of iodine is low. This demonstrates that the polydextrose polymer forms a complex with the iodine or tri-iodide ion since in the absence of polydextrose, the percent of iodine loss is 99.3% from the iodine solution. EXAMPLE 2 0.7 g of pulverized, resublimed iodine is added portionwise to 70 cc of a 5% polydextrose solution, with constant stirring at 35° C. The resultant solution is heated to 65° C., with the temperature being maintained for 2 hours. The solution is then allowed to cool to room temperature overnight, filtered, and freeze dried to a fine powder. The available iodine in this preparation was assayed at 0.01%. EXAMPLE 3 3.5 g of pulverized, resublimed iodine was added at 40° C. to 200 cc of a 10% polydextrose solution, with stirring. The mixture was heated slowly to 75° C., maintained for 4 hours at this temperature, and then allowed to cool, followed by filtering and freeze-drying. The available iodine content of the resulting preparation was assayed at 0.14%. EXAMPLE 4 5.25 g of pulverized, resublimed iodine was added at 40° C. to 200 cc of a 15% polydextrose solution in water, with stirring. The resulting mixture was heated to 70° C., with a temperature being maintained for 4 hours. The reaction solution was then cooled over an ice bath, filtered, and freeze-dried to a fine powder. Available iodine content was determined as 0.48%. EXAMPLE 5 6.5 g of pulverized, resublimed iodine was added to 200 cc of a 60% polydextrose solution, with stirring. The mixture was then heated with stirring for 4 hours at 75° C. Then, the resulting composition was allowed to cool to room temperature, filtered, and freeze-dried. Available iodine content was assayed as 0.93%. EXAMPLE 6 6.5 g of resublimed iodine was added to 200 cc of a 60% polydextrose solution in water, at 40° C. with stirring. After completion of the addition of iodine, ten drops of 47-51% hydriodic acid was added. The mixture was then heated to 75° C., with the temperature being maintained for 4 hours. The resulting solution was cooled and filtered, with the available iodine content thereof determined as 1.026%. EXAMPLE 7 6.5 g of resublimed iodine was added with stirring at room temperature to 100 cc of 60% polydextrose solution in water. Ten drops of hydriodic acid was then added to the solution. The mixture was then stirred at room temperature for one hour, filtered an freeze-dried. Available iodine content was determined as 0.22%. EXAMPLE 8 3.25 g of resublimed iodine was added with stirring to 100 cc of a 60% polydextrose solution. After completion of the iodine addition, 10 drops of hydriodic acid was added. The mixture was then stirred at room temperature for 1 hour, then filtered and freeze-dried, with available iodine content determined as 0.29%. EXAMPLE 9 3.25 g of resublimed iodine and 10 drops hydriodic acid were simultaneously added at room temperature to 100 cc of a 60% polydextrose solution in water, with concomitant stirring. The resulting mixture was then heated to 75° C., and the temperature maintained for 1 hour thereat. The mixture was then cooled to room temperature and filtered. The available iodine content of the resulting composition was determined at 0.7%. EXAMPLE 10 20 g of polydextrose was added to 100 cc of water. 4.44 cc of iodine solution containing 1.8 g. potential iodide and 3.2 g iodine was then added to the resulting clear polydextrose solution. After the addition of the iodine solution thereto the resulting mixture was stirred for 1 hour at room temperature, then filtered and freeze-dried to a fine powder. Available iodine content was determined as 8.9%. EXAMPLE 11 20 g polydextrose was dissolved in 100 cc of water at room temperature, with stirring. 2.55 cc of iodine solution, prepared as in Example 10, was then added to the stirred solution. The resulting mixture was then subsequently stirred for one hour and filtered, with available iodine content thereof determined as 5.2%. EXAMPLE 12 400 g polydextrose was dissolved in 2,000 cc water with stirring at room temperature. 83.63 cc iodine solution prepared as in Example 10, was then added with stirring. The resulting mixture was heated to 65° C., with the temperature being maintained for one hour. The resulting solution was then cooled and spray-dried, with available iodine content as 0.05%. EXAMPLE 13 20 g polydextrose was dissolved in 100 cc of water at room temperature with stirring. 1.07 cc of iodine solution prepared as in Example 10 was then added to the solution followed by stirring for 1 hour. The solution was filtered, with available iodine content determined as 2.01%. EXAMPLE 14 1.6 cc of iodine solution prepared as in Example 10 was added dropwise with stirring to 100 cc of a 20% polydextrose solution in water. The resulting solution was stirred for one hour at room temperature and filtered. The available iodine content thereof was determined as 3.2%. EXAMPLE 15 2.01 cc of iodine solution prepared as in Example 10 was added with stirring to 100 cc of a 20% polydextrose solution in water. The solution was stirred for 1 hour at room temperature and then filtered, with available iodine determined as 4.03%. EXAMPLE 16 3.52 cc iodine solution prepared as in Example 10 was added dropwise with stirring to 100 cc of a 20% polydextrose solution in water. The solution was stirred for 1 hour at room temperature and then filtered, with available iodine content determined as 7.01%. EXAMPLE 17 2.69 cc of iodine solution prepared as in Example 9 was added with stirring to 100 cc of a 20% polydextrose solution in water. The resulting solution was heated to 55° C., with the temperature being maintained thereat for 1 hour. The resulting heated solution was then cooled and filtered, with available iodine content determined as 5.1%. EXAMPLE 18 20 g of polydextrose was dissolved in 100 cc of water at room temperature. 4.54 cc of iodine solution prepared as in Example 9, was then added with stirring. The solution was heated to 55° C., with the temperature being maintained for 1 hour. The available iodine content was determined as 7.25%. EXAMPLE 19 20 g of polydextrose was dissolved in 100 cc of water at room temperature. 0.4 cc of iodine solution was then added with stirring, followed by heating to 55° C. and maintainance with the temperature thereat for 1 hour. Cooling and filtering followed, with the available iodine content assayed at 1.06%. EXAMPLE 20 600 g of polydextrose was dissolved in 3,000 cc of water at room temperature. 133 cc of iodine solution was then added to the polydextrose solution, followed by heating to 55° C., with the temperature being maintained for 1 hour at that level. The resulting composition was then cooled, filtered, and freeze-dried to a fine powder, with available iodine content determined as 7.19%. EXAMPLE 21 20 g of polydextrose was dissolved in 17 cc of water at room temperature. 4.28 cc of iodine solution was then added, with the resulting mixture being heated to 55° C. The temperature was maintained for one hour, followed by cooling and filtering the solution. The solution was then freeze-dried and assayed for iodine, which yielded an available iodine content of 5.34%. EXAMPLE 22 600 g of polydextrose was dissolved in 3,000 cc of water at room temperature. 155.0 cc of iodine solution that was prepared from 43.55 g of potassium iodide (KI) and 112.37 g. of iodine, was then added to the polydextrose solution. Subsequently, the resultant solution was heated to 55° C. with stirring, with the temperature being maintained at that level for 1 hour. The resultant solution was cooled and filtered, with the filtrate being assayed for available iodine after 6 weeks of standing at room temperature. The iodine content was found to be 8.39% after standing at room temperature for six weeks. Aliquots of the solution prepared in this example were freeze-dried. The resulting batches were then combined and assayed for available iodine, which was found to total 7.69%. EXAMPLE 23 20.0 g of polydextrose was dissolved in 4 cc of water at room temperature, followed by heating of the resultant solution in an oil bath at 75° C. with stirring. 2.0 g of iodine was added portionwise during the stirring in the oil bath. Heating and stirring then continued for one-half hour, followed by cooling, and subsequent drying in a vacuum over phosphorous pentoxide. The weight of the dry polydextrose iodine complex was 20.5 g, with the assayed available iodine content being 0.1%. EXAMPLE 24 40 g of polydextrose powder was dissolved in 100 cc of water, with stirring and heating at 60° C. 9.72 g of resublimed iodine was added portionwise over 15 minutes to the clear solution during the stirring and heating at 70° C. The temperature was then raised to 90-95° C., with stirring for 30 minutes. The solution was then cooled to room temperature, and the further cooled on an ice bath, followed by filtering. The crystals were dried in a vacuum over anhydrous calcium chloride, with the assayed available iodine content found to be 0.62%. EXAMPLE 25 One gram of resublimed iodine was dissolved in 20 cc of carbon tetrachloride (CCl 4 ). 5.0 g of polydextrose powder was added to the clear iodine solution, with stirring. The resulting suspension was stirred for 15 minutes, and then 0.3 cc of hydriodic acid (47-51% concentration) was added in dropwise fashion, over 5 minutes. The resulting suspension was then stirred for 4 hours, followed by filtering by suction The resulting solid was partially in powder form, and was dried under vacuum over phosphorus pentoxide. The resulting weight of the solid powder was 2.9 g, with an available iodine content of 0.19%, while the weight of the gummy solid portion of the product was found to be 1.5 g, with an available iodine content of 3.8%. EXAMPLE 26 20 g of polydextrose powder was dissolved in 100 cc of water with stirring, followed by addition of 10 cc of iodine solution to the clear polydextrose solution. The iodine solution so added was prepared from 8.2 g of potassium iodine (KI) and 13 g of iodine in 25 cc of water. The resulting iodine-polydextrose solution was stirred for half an hour, filtered, and then freeze-dried to a fine powder of the polydextrose-iodine iodophor complex. Available iodine content of this composition was determined to be 10.34%. EXAMPLE 27 20 g of polysaccharide Ficoll polymer was dissolved in water in a 200 ml volumetric flask, and water was then added to raise the volume of the solution to 200 ml. 4 g of finely-ground iodine was then added to the solution, which was slowly heated to 95° C., with the temperature being maintained for one-half hour. The solution was then cooled to ambient temperature, filtered, and freeze-dried. The assayed iodine solid complex was determined to have 1.6% available iodine content. EXAMPLE 28 50 g of polysaccharide Ficoll 700 polymer was dissolved in water in a 500 ml volumetric flask, with water then added to raise the volume of the solution to 500 ml. 10 g of finely-powdered iodine was then added to the solution, followed by heating for 5.5 hours at 95° C. with stirring. The solution was allowed to stand overnight, filtered, and then freeze-dried. The available iodine content thereof was assayed as 2.1%. EXAMPLE 29 2.0 g of iodine dissolved in 75 ml of 1,2-dichloroethane, was added to 20 g of Ficoll 700 polymer in 200 ml of 1,2-dichloroethane, with stirring. The suspension was heated to 79° C., with the temperature then being maintained for 2 hours. The resulting product was allowed to cool overnight, filtered, and freeze dried to a fine powder. The available iodine content was assayed as 0.1%. EXAMPLE 30 20 g of Ficoll polymer was dissolved in 100 ml of water. 4.84 ml of iodine solution was then added with stirring for 2 hours, at room temperature. The resultant liquid was assayed for available iodine, which was determined to be 9.62%. EXAMPLE 31 7.45 ml of iodine solution prepared according to Example 10, was added to 100 ml of a 20% solution of Ficoll polymer dissolved in water, with stirring. Stirring was continued for one hour at room temperature with the solution then being assayed for available iodine. The available iodine was determined to be 14.5%. EXAMPLE 32 7.0 ml of iodine solution was added to 100 ml of a 20% solution of Ficoll 700 polymer in water, with stirring. The solution was then stirred for an additional hour at room temperature. The resulting solution was filtered and assayed for available iodine, which was determined to be 13.04%. EXAMPLE 33 0.42 ml of iodine solution was added to 100 ml of a 20% solution of Ficoll 700 polymer in water, with the resulting solution being stirred for an additional hour at room temperature. The solution was then assayed for available iodine content, which was determined to be 1.25%. EXAMPLE 34 2.2 ml of iodine solution was added to 100 ml of a 20% solution of Ficoll 700 polymer in water with the resulting solution being stirred for one hour at room temperature and assayed for available iodine content. The available iodine content was determined to be 4.95%. EXAMPLE 35 7.3 ml of iodine solution was added to 100 ml of a 20% solution of Ficoll polymer in water, followed by stirring for one hour at room temperature. The available iodine content that was assayed of this solution was 15.29%. EXAMPLE 36 4.4 ml of iodine solution was added to 100 ml of a 20% solution of Ficoll polymer in water, with heating and stirring at 55° C. for one hour. The solution was allowed to cool to room temperature, and then filtered and assayed for iodine content. The available iodine content was determined to be 7.66%. EXAMPLE 37 4.4 ml of iodine solution was added to 100 ml of a 20% solution of Ficoll polymer in water, with heating and stirring at 55° C. for one hour. The solution was allowed to cool, and the resulting Ficoll-iodine complex solution was assayed for available iodine content, determined to be 9.73%. EXAMPLE 38 7.26 ml of iodine solution was added to 100 ml of a 20% solution of Ficoll polymer in water, with stirring for one hour at 55° C. The resulting Ficoll-iodine complex solution was assayed for available iodine content, determined to be 12.29%. EXAMPLE 39 100 ml of a 20% solution of Ficoll polymer in water was heated to 45° C., with 7.3 ml of iodine solution then being added with stirring. The temperature of the resulting solution was maintained for one hour, followed by cooling. The liquid was then filtered and assayed for available iodine content, determined to be 14.3%. EXAMPLE 40 4.6 ml of iodine solution was added to 100 ml of 20% solution of Ficoll polymer in water, at 45° C. The temperature was maintained for one hour, with stirring. The resulting solution was cooled, filtered, and assayed for available iodine content, determined to be 9.05%. EXAMPLE 41 7.6 ml of iodine solution was added to 100 ml of a 20% solution of Ficoll 700 polymer in water, with stirring at 65° C. The temperature was maintained for one hour, followed by cooling of the solution and assaying for available iodine content. The available iodine content was determined to be 15.1%. EXAMPLE 42 4.6 ml of iodine solution was added with stirring to 100 ml of a 20% Ficoll polymer solution in water, with stirring at 65° C. The temperature was maintained for one hour, with the solution then being cooled and assayed for available iodine content, which was determined to be 8.8%. EXAMPLE 43 20 g of Ficoll 700 polymer was dissolved in 150 cc of water. 20 cc of iodine solution which was prepared according to Example 10 was then added to the clear Ficoll polymer solution with stirring. The resulting solution was then stirred for an additional one-half hour, filtered, and the resulting Ficoll-iodine iodophor complex was freeze-dried to form a fine powder. The available iodine content was assayed to be 24%. EXAMPLE 44 1.39 g of polydextrose-iodine complex with 7.0% available iodine content was dissolved in 50 cc of water. 30 g of glycerin, 0.06 g of buffer (prepared by mixing and grinding 15 g of disodium phosphate and 71 g of anhydrous citric acid), and 0.25 g of polysorbate 80, were all added to the clear solution of PDI. The components were all thoroughly dissolved in the solution, which was then quantitatively transferred to a 100 ml volumetric flask, and raised to the 100 ml volume by addition of distilled water. The resulting solution was assayed for available iodine content, which was determined to be 0.1% by weight/volume. EXAMPLE 45 1.39 g of polydextrose-iodine complex (PDI) having a 7.0% available iodine content, is dissolved in 50 ml of water. 1 g of glycerin, 0.06 g of buffer prepared as outlined in Example 44, and 0.25 g of polysorbate 80 are all added to the PDI solution. The components are all thoroughly dissolved, with the solution quantitatively transferred to a 100 ml volumetric flask, with the volume thereof being raised to 100 ml by the addition of distilled water. The available iodine content that was assayed, was found to be 0.1 weight/volume of solution. EXAMPLE 46 27.78 g of polydextrose iodine complex having a 7.07% available iodine content, was dissolved in 50 ml of water, with 30 g of glycerin, 0.25 g of Alipal CO-436, 1.119 g of buffer being added thereto. All components were thoroughly dissolved, with the solution quantitatively transferred to a 100 ml volumetric flask. The solution volume was raised to 100 ml by the addition of more water. The available iodine content that was assayed, was determined to be 2.0%. EXAMPLE 47 13.89 g of polydextrose iodine complex was dissolved in 50 ml of water. 30 g of glycerin, 0.25 g of Alipal CO-436 and 0.56 g of buffer, were all added to the solution, which was then quantitatively transferred to a 100 ml volumetric flask. The volume of the solution was then raised to 100 ml by the addition of more water. The available iodine content of the resulting solution was determined to be 1.0%. EXAMPLE 48 3.47 g of polydextrose iodine complex having 7.07% available iodine content, is dissolved in 50 ml of water. 30 g of glycerin, 0.25 g of Alipal CO-436, and 0.14 g of buffer, are all then added and dissolved in the PDI complex solution. The solution is quantitatively transferred to a 100 ml volumetric flask, with the volume thereof being raised to 100 ml by the further addition of water. The available iodine content was assayed at 0.25%. EXAMPLE 49 1.39 g of polydextrose iodine complex was dissolved in 50 ml of water. 30 g of glycerin, 0.25 g of Alipal CO-436, and 0.14 g of buffer are all added and dissolved in the PDI solution. The solution was then quantitatively transferred to a 100 ml volumetric flask, and raised to 100 ml volume by addition of more water. The available iodine content therein was determined to be 0.1%. EXAMPLE 50 13.95 g of polydextrose iodine complex was dissolved in 50 cc of water. 1 g of glycerin, 0.25 g of Alipal CO-436, and 0.56 g of buffer were all then added to the PDI solution. The solution was transferred quantitatively to 100 ml volumetric flask, where water was then added to raise the volume of the solution to 100 ml. The available iodine content was determined to be 1%. EXAMPLE 51 13.95 g of polydextrose iodine complex was dissolved in 50 ml of water. 1 g of glycerin, 0.25 g of Alipal CO-436, and 0.056 g of buffer were all then added to the PDI complex. The resulting solution was quantitatively transferred to a 100 ml volumetric flask, where the overall volume of the solution being raised to 100 ml by addition of more water. The available iodine content was determined to be 0.1%. EXAMPLE 52 14.1 g of polydextrose iodine complex, having a 7.0% available iodine content, 1 g of glycerin, and 0.25 g of Hamposyl L-30 (available as a 30% solution) are all dissolved in about 80 ml of water. 0.914 g of buffer was added portionwise to the solution until the pH thereof was in the range of 4.9-5.1. The solution was then quantitatively transferred to a 100 ml volumetric flask, with the volume of solution being raised to 100 ml by addition of more water. The final pH of the solution was determined to be 5.01, with the available iodine content therein determined as 1%. EXAMPLE 53 14.1 g of polydextrose iodine complex, 1 g of glycerin, and 0.3 g of ammonium myrth sulfate (available with a 60% concentration), are all dissolved in about 80 ml of water. Citric acid/disodium phosphate buffer prepared according to Example 44, was added portionwise to lower the pH to 5.01. The solution was then quantitatively transferred to a 100 ml flask, with the volume of solution being raised by addition of more water to 100 ml. The final pH of the composition was determined to be 5.0, with the available iodine content being 1%. EXAMPLE 54 14.1 g of polydextrose iodine complex having a 7.0% available iodine content, 1 g of glycerin, and 0.25 g of Mirataine CBS, are dissolved in about 80 ml of water, with buffer being added portionwise, until the pH is lowered to 5.0. The solution is then quantitatively transferred to a 100 ml volumetric flask, with the volume thereof being raised to 100 ml by addition of more water. The final pH of the composition was determined to be 5.0, with the available iodine content being 1%. EXAMPLE 55 14.0 g of polydextrose iodine complex, 1.0 g of glycerin, and 0.25 g of Hamposyl TL-40, are dissolved in approximately 80 ml of water. Citric acid/disodium phosphate buffer prepared according to Example 44 is added portionwise to the solution until the pH is lowered to 5.5. A few drops of 10% hydrochloric acid are then added dropwise to further lower the pH of the solution to 5.0. The solution is then quantitatively transferred to a 100 ml flask, where more water is added to raise the volume of solution to the concomitant 100 ml level. The available iodine content was determined to be 1.0%, with the pH of the solution being 5.0. EXAMPLE 56 5 cc of iodine solution prepared according to Example 10, was added to 20 g of polydextrose polymer dissolved in 100 cc of water, with stirring. The resulting solution was heated to 55° C., and the temperature maintained at the level for one hour. The solution was then cooled over ice, filtered, assayed, and then freeze-dried. The freeze-dried product was further assayed. The analysis resulted in a determination of 8.69% available iodine content of the liquid assayed before freeze-drying, and 8.15% available iodine content of the solid powder after freeze-drying. EXAMPLE 57 12 cc of iodine solution containing 621.81 mg I 2 /cc and prepared according to Example 10, was added with stirring to 20 g of polydextrose polymer that was dissolved in 100 cc of water. The resulting solution was heated to 55° C., with the temperature being maintained for one hour. The liquid polydextrose iodine (PDI) complex was assayed, and cooled, filtered, and freeze-dried, with the freeze-dried product also being assayed. The assay of the liquid solution resulted in a determination of 18.6% available iodine content, with the assay of the freeze-dried product determining 17.05% available iodine content, after freeze-drying. EXAMPLE 58 4 cc of iodine solution prepared according to Example 10 was added with stirring to 20 g of Ficoll 400 polymer dissolved in 100 cc of water. The solution was heated to 55° C., with the temperature being maintained at the level for one hour. The Ficoll polymer iodine complex solution was cooled, filtered, freeze-dried, and then assayed for available iodine content, determined to be 9.25%. EXAMPLE 59 400 ml of iodine solution was added with stirring to 20 g of Ficoll 700 polymer dissolved in 100 cc of water. The solution was heated to 55° C., with the temperature being maintained at that level for one hour. The solution was then cooled, filtered, freeze-dried, and assayed for available iodine content determined to be 8.91%. EXAMPLE 60 600 g of polydextrose was dissolved in 3,000 cc of water with vigorous stirring, until a clear solution was obtained. 71 cc of an iodine solution containing 63 g I 2 , was then added to the clear solution with stirring. The resulting batch was heated to 55° C., with the temperature maintained at that level for one hour. The batch was then cooled to room temperature and filtered. The liquid product was freeze-dried, with the freeze-dried solid product then being assayed for available iodine, determined to be 3.25%. EXAMPLE 61 600 g of polydextrose was dissolved in 3,000 cc of water with vigorous stirring, until a clear solution was obtained. 155 cc of iodine solution prepared from 137 g I 2 , was then added to the polydextrose solution with stirring. The resulting batch was heated to 55° C., with the temperature maintained at that level for one hour. The solution was then cooled to room temperature and filtered. The PDI complex can be used in the liquid form, however it is preferably freeze-dried to obtain the solid form of the PDI complex. The PDI complex was so freeze-dried, and assayed for available iodine content, which was determined to be 7.45%. EXAMPLE 62 82 g potassium iodide (KI) was dissolved in 200 cc of water. Iodine (I 2 ) was added, with stirring for one hour at room temperature. The resulting solution was filtered and assayed for available iodine content, which was determined to be 888.44 mg I 2 /cc. This iodine solution was used in the preparation of the various PDI complexes, and Ficoll polymer-iodine complexes, noted supra. EXAMPLE 63 10 g polydextrose and 2 g iodine (particle size 40 mesh) were thoroughly mixed and placed in a 4 oz. wide-mounth jar. 0.12 cc water was then added by syringe, and the jar was capped. The mixture was shaken for 24 hours. No apparent reaction was noted between the polydextrose and iodine crystals added therein. EXAMPLE 64 10 g polydextrose and 2 g elemental iodine were thoroughly mixed and placed in a 4 oz. wide-mouth jar. 0.63 cc water was added by syringe, and the jar capped. The mixture was shaken for 24 hours. No apparent reaction was noted. EXAMPLE 65 10 g polydextrose and 2 g elemental iodine were thoroughly mixed and placed in a 4 oz. wide-mouth jar. 1.33 cc water was added by syringe, and the jar capped. The mixture was shaken for 24 hours. The formation of a polydextrose water gel was observed. The gel had a greenish tinge. However, iodine crystals were visible within the gel, and no apparent reaction took place. The preceding description of the present invention is merely intended as exemplary, and is not intended to limit the scope thereof in any way, shape, or form.

New iodophors are provided which exhibit effective degerming of skin, mucous membranes of animals and surfaces of inanimate objects and which provide broad spectrum microbicidal action without toxicity or irritation. The iodophors of the invention are complexes of iodine with polydextrose or with the polymer resulting from the copolymerization of sucrose and epichlorohydrin. The invention further relates to germicidal compositions containing such complexes and to methods of producing the complexes.

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to the transfer and conveyance of sponge iron pellets after they have been manufactured in a direct reduction reactor unit. More specifically the invention relates to a sponge iron transfer device which includes heat monitoring devices adapted to segregate different temperature products from each other. 2. Description of the Prior Art The Taylor U.S. Pat. No. 3,411,005 patented Nov. 12, 1968 utilizes an infra-red detector system which is utilized with a conveyor. However, the present system is particularly unique in that it comprises a means for monitoring the temperature of sponge iron and includes an arrangement responsive to different temperatures of the pellets for segretating good product from bad product. SUMMARY OF THE INVENTION The present invention has to do with a transfer or conveyor system which moves sponge iron pellets from a direct reduction reactor unit to another part or unit of the overall plant. Some sponge iron pellets produced in such a reactor have a tendency to continue oxidation for a period of time after it leaves the reactor unit and similar to spontaneous combustion again heats up to a very high temperature. Pellets so heated up above a certain temperature are considered "bad product" and must be segregated from "good product" which then, later is utilized in a smelter in the steel making process. The conveyor includes at one end a discharge chute arrangement which includes gate valves movable to segregate the bad product and good product into different chutes. The operation of the gates is effected by fluid cylinder and piston rod units which are responsive to effectively segregate the products in response to valves which are actuated by infra-red sensors. The infra-red sensors are mounted in an enclosure which in turn is positioned over the conveyor, the said enclosure having a lower opening. As the product moves with the conveyor, the infra-red sensors detect the temperature and in turn send a signal which will cause the gates to be actuated for segregating the bad product from the good. The temperature differential, of course, determines when the activation of the gate mechanism takes place. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a plan view, partially in section of an enclosure containing infra-red sensor devices; FIG. 2 is a cross-sectional view taken along the line 2--2 at FIG. 1; FIG. 3 is a cross-sectional view taken along the line of 3--3 of FIG. 2; FIG. 4 is a cross-sectional view taken along the line 4--4 of FIG. 2; FIG. 5 is an end elevational view of one infra-red sensor device mounted on a support within an enclosure; FIG. 6 is a side elevated view of the infra-red sensor device disclosed in FIG. 5; FIG. 7 is a side elevated view taken along the line 7--7 of FIG. 6; FIG. 8 is a view taken substantially along the line 8--8 of FIG. 7, and FIG. 9 is a schematic view of the infra-red sensor arrangement including relevant operating components of a heat monitoring and transfer system. DESCRIPTION OF THE PREFERRED EMBODIMENT The Celada U.S. Pat. Nos. 3,467,368 and 3,900,247 respectively disclose a reactor and a process for producing sponge iron pellets from iron ore which is then utilized in a smelter apparatus for the production of steel. The present invention involves an apparatus for handling or transferring the pellets so produced. A movable conveyor 10 of conventional construction includes a belt 11 which is supported on conventional conveyor structure, driven by suitable motor means, neither of which is disclosed and being conventional in the art. The belt must be of a type highly resistant to high temperatures which are encountered in the handling of newly manufactured sponge iron. A sensor enclosure 12 is suitably supported above the belt 11 and includes a housing 13 having end walls 14 connected to side walls 15. A top wall 16 connects the end and side walls. A flange 17 is provided at the lower end of the enclosure 12 and is coextensive therewith defining an opening 19. A box structure 20 is supported from channel structures 18 in turn supported on the flange 17. The structure 20 includes side walls 21 and end walls 22 connected thereto. The box structure 20 includes a lower opening 23. Back-up plates 24 are connected to the box structures 20 and channel structure 18 by means of fasteners 25. As best shown in FIGS. 1, 2 and 3, horizontal pipes 25, 26 and 27 are supported on angle supports 28 spaced from the upper end of the housing 13. The pipes 25, 26 and 27 are positioned by end brackets 29 through which they extend. The pipe 25 is the water inlet, pipe 26 is the water outlet and pipe 27 is the air pipe. The ends of the pipes are closed by caps 30. Suitable threaded connectors 31 are connected respectively to sources of water in, water out and air. Referring now particularly, to FIGS. 4 through 8, an infra-red sensor device 32 is disclosed. The device 32 includes an upper housing part 33 and an intermediate housing part 34 secured together by cap screws 35. The device includes an infra-red sensor device and all the necessary components which, however, are conventional in the art and commercially available, the specific type forming no part of the present invention. Commercial devices are known as E 2 THERMODOT-Model TD-22 (not shown) available from E 2 Thermodot Incorporated Corporation located in Carpinteria, Calif. or the IRCON MOOLINE INFRA-RED OPTICAL SENSOR, SERIES 7000, available from Ircon Incorporated Corporation located in Skokie, Ill. The INFRA-RED SENSOR is of a type which will record temperature readings. A lower housing part 36 is connected to the intermediate housing part 34 by means of cap screws 37. The lower housing part 36, by means of spacers 38 and 39 are secured to a horizontal plate 40 of a bracket 41. The bracket 41 is connected by means of cap screws 42 to the upper housing part 33. Split ring shock mounts 43 connect each of the sensor devices 32 to a horizontal pipe 44 which is provided at its opposite ends with sleeve members 45 having open end slots 46 which are engaged by the ends of flange members 47. The flange members are rigidly secured to the sleeve members 45 by means of screws 48. The flange members 47 are connected to spacer blocks 49 by means of screws 49' by screws 50. The above arrangement provides for vertical adjustment of the pipe 44 and infra-red sensor housings connected thereto. The lower housing 36 includes a lower closure lens 51 which encloses the housing structure through which infra-red scanning can be accomplished. Each of the infra-red sensors 32 is provided with one air inlet and water inlet and outlet. The air pipe 27 includes air connections 52, which are in communication with air hoses 53, each in turn being connected to an air connection 54 on the lower housing part 36, as best shown in FIG. 3. Also, as best shown in this FIG. 3, the sensor devices 32 are reversed in that the brackets 41 are attached identically to each sensor device in the same manner. FIG. 2 AND FIG. 3 disclose that four infra-red sensor devices 32 are provided in the present enclosure though more can be added if desired. The pipe 25 includes a connector 55 which is in communication with a water-in hose 56 in turn connected by connector 55' on the sensor 32, the latter being provided on the intermediate housing portion 34. On the same side of the sensor, there is provided the air inlet connector 54. A water outlet connector 57 on the opposite side of each sensor 32 communicates with a water out hose 58 in turn connected to a water out connector 59 on the pipe 26. The air hose provides for the cleansing of dust from the sensor and lenses whereas the water connection and hoses provided continuing coolant to the sensors for cooling them. The intermediate chamber A of the intermediate housing part 34 is sealed from the lower chamber B of the lower housing part 36 and is separated by a lens 51'. Water running through chamber A cools the infra-red sensors. Chamber B which is the air chamber is vented and the air blown into chamber B keeps the lens 51 and 51' clean. FIG. 9 is a schematic diagram disclosing generally the arrangement for transporting the sponge iron and for segregating the bad product from the good product. The conveyor belt 11 is shown in proximity to a chute structure 60 comprising a first vertical hot product chute 61 and diagonally extending chutes 62 which direct good product to its desired destination. A hopper 63 is adapted to receive the sponge iron from the conveyer belt 11. Gates 64 are hingedly connected to the arrangement and by means of air cylinders or fluid extensible devices 65 (cylinder, piston and piston rod) are moved to different positions blocking and unblocking certain of the chutes. The sensor station 66 essentially comprises the sensor enclosure which is not specifically detailed in FIG. 9 but which is disposed over the conveyor belt 11 at a suitable position. A control box 67 supplies power to the sensors through a power connection 68 from the control box. The water in hoses and connections, and the water out hoses and connections are exemplified by lines 69 and 70 which include a temperature maintenance system 71 recirculating water to cooling unit 72 located within the control box 67. The control box, by a lead 73 is connected to limit switches 74 indicating the position of the gates 64. The control box 67 includes means to send a signal if hot product is detected on the conveyor by the infra-red sensors. The signal is transmitted to a signal diverter 75 which actuates air valves 76 and 77 to close the gates 64 whereupon the hot sponge iron is dumped into hopper 63 and is directed by vertical chute 61 to a particular location. As the good product is then scanned by the sensors, the gates are moved to their original position. As disclosed on the drawings, the gates are either in a closed position relative to both chutes 62, or one of the gates 64 is open whereupon the other gate 64 is closed. The valve directs air to and from opposite sides of the fluid extensible devices 65 by means of air conduits 78 and 79 in conventional fashion. The reference character 80, in FIG. 9, represents the continued air connections 53, 54 and 55 disclosed in the other figures. The Operation The infra-red sensors 32 are cooled by the water outlet and inlet connections as indicated and the air connections provide for the removal of dust from the optical parts of the sensor devices. The chamber A may be double walled in the intermediate housing with water flowing in and out in cooling the sensors. As the normal temperature product moves along the conveyor 11, the sensors, by means of the control box, may indicate the temperature on a suitable gauge but no signal to the signal diverter is transmitted. The gates are in the position indicated in FIG. 9 and the good product is dumped from the conveyor 11 into one of the chutes 62 to the desired station. However, as "hot product" sponge iron, at a predetermined temperature, is sensed by the sensors then the control box sends a signal to the signal diverter which causes air valve 76 or 77, depending on the position of the signal diverter, to function and close both of the gates 64 whereupon the hot product is channelled through chute 61 to a certain destination. After the hot product is dumped, the signal diverter in response to "good" product temperature, provides for the gates again to assume the position as indicated. The system is so set only one gate will be open at any time during which good product is being discharged and may be controlled so that either one or the other of chutes 62 is in operation. During tests of the aforementioned arrangement, the sensors were capable of detecting hot spots in the sponge iron during conveyer speeds between 300-400 feet per minute. The height of the sensor above the conveyor was arranged about 4'8" with satisfactory results. In one particular test indicating a proper temperature of pellets, the temperatures were 157° F., 150° F., 145° F. and 135° F. Hot spots which were pellets overheating would indicate temperatures as high as 495° F. which of course would indicate bad product which would actuate operation of the system to segregate the same.

A heat monitoring and conveying arrangement for newly manufactured sponge iron pellets which were heated up during manufacture at a direct reduction reactor unit, and are ready for transfer to another unit of the plant. The arrangement includes conveying means for moving the pellets, and infra-red sensors supported within an enclosure positioned over the conveying means. The infra-red sensors are adapted to sense the temperature of the sponge iron pellets, and actuate means for segregating sponge iron pellets when heated to a temperature higher than a predetermined temperature required for further processing of the sponge iron pellets.

CROSS-REFERENCE TO RELATED APPLICATIONS [0001] This application claims benefit to U.S. Provisional Application No. 61/052,816, filed May 13, 2008, the contents of which are hereby incorporated by reference. FIELD OF THE INVENTION [0002] The present invention relates to an improved method for preparing dihydrothieno[3,2-d]pyrimidine diols, particularly a 6,7-dihydro-thieno[3,2-d]pyrimidine-2,4-diol, and similar pyrimidine diols. More particularly, the present invention sets forth a method for preparing pyrimidine diols in an efficient, high-yielding reaction that does not require expensive and potentially unstable intermediates. The pyrimidine diols are useful for a variety of purposes including intermediates in the synthesis of pharmaceuticals. DESCRIPTION OF RELATED ART [0003] Dihydrothienopyrimidines are commonly synthesized from dihydrothieno[3,2-d]pyrimidine diols, for example, as described in U.S. Patent Publication 2007/0259846 and WO 2006/111549. The synthesis of the dihydrothieno[3,2-d]pyrimidine diol intermediates has proved challenging to implement in an efficient reaction that does not require expensive and potentially unstable intermediates and also results in obtaining the desired product in high yield and purity. For example, U.S. Pat. No. 3,318,881 reports the condensation of a keto-dihydrothiophene-2-carboxylic acid methyl ester with s-ethylisothiourea to form 2-ethylsulfanyl-6-7-dihydrothieno[3,2-d]pyrimidin-4-ol, which can then be subjected to acid hydrolysis to yield a dihydrothieno[3,2-d]pyrimidine diol as described in U.S. Patent Publication No. 2007/0259846. This process, however, provides only modest yields, requires the use of s-ethylisothiourea or other s-alkylisothioureas, which are expensive and have limited availability, and produces an unpleasant stench associated with the release of ethanethiol during the acid hydrolysis. Attempts to substitute the less expensive urea for the s-alkylisothiourea in the condensation reaction have been unsuccessful because of poor yields, for example as reported by Ohno et al. (1986) Chem. Pharm Bull. 34:4150. [0004] Other pyrimidines may be synthesized from pyrimidine-2,4-diols, such as 6,7-dihydro-5H-cyclopentapyrimidine-2,4-diol, in modest yields. For example, diols reported by Sekiya et al. (1980) Eur. J. Med. Chem. 15, 4: 317 were used to generate 2,4-diamino-5,6-polymethlenepyrimidine derivatives for use as hypoglycemic, antihypertensive and anorexigenic agents. However, because of the above-discussed limitations, a need in the art to prepare intermediate diols via improved and efficient synthetic methods remains. BRIEF DESCRIPTION OF THE INVENTION [0005] The present invention provides an improved, high-yield method for preparing dihydrothieno[3,2-d]pyrimidine diols, and similar pyrimidine-2,4-diols. The disclosed method for preparing a compound of formula I: [0000] [0000] comprises reacting a starting compound of the formula II [0000] [0000] with urea, in the presence of acid, to yield an intermediate of the formula IV [0000] [0000] and cyclizing the intermediate of the formula IV with a base, to yield the final product of the formula I. [0006] The present invention also provides a method for preparing additional pyrimidine diols. For example, a method for preparing a compound of formula X: [0000] [0000] comprises reacting a starting compound of the formula VIII [0000] [0000] with urea, in the presence of acid, to yield an intermediate of the formula IX [0000] [0000] and cyclizing the intermediate of the formula IX with a base, to yield the final product of the formula X. [0007] The acid may be selected from acetic acid, trifluoroacetic acid, perchloric acid, toluene sulfonic acid, hydrobromic acid, hydrochloric acid, sulfuric acid and nitric acid. In a preferred embodiment, the acid is hydrochloric acid. The base may be selected from the group consisting of metal hydride bases, metal alkoxide bases, and metal phosphate bases. In a preferred embodiment, the base is MeONa. In another preferred embodiment, the base is NaOH. [0008] In one embodiment of the invention, the compound of formula I is 6,7-dihydro-thieno[3,2-d]pyrimidine-2,4-diol (formula Ia), 6-methyl-6,7-dihydro-thieno[3,2-d]pyrimidine-2,4-diol (formula Ib), 6-ethyl-6,7-dihydro-thieno[3,2-d]pyrimidine-2,4-diol (formula Ic), 6-phenyl-6,7-dihydro-thieno[3,2-d]pyrimidine-2,4-diol (formula Id), 6,6-dimethyl-6,7-dihydro-thieno[3,2-d]pyrimidine-2,4-diol (formula Ie) or 7-Methyl-6,7-dihydro-thieno[3,2-d]pyrimidine-2,4-diol (formula If). [0009] In another embodiment of the invention, the compound of formula X is 9H-indeno[2,1-d]pyrimidine-2,4-diol (formula Xb). [0010] The above and still further features and advantages of the present invention will become apparent upon consideration of the following detailed description of specific embodiments thereof. DETAILED DESCRIPTION OF THE INVENTION [0011] Reference will now be made in detail to the presently preferred embodiments of the invention, which, together with the following examples, serve to explain the principles of the invention. These embodiments are described in sufficient detail to enable those skilled in the art to practice the invention, and it is to be understood that other embodiments may be utilized, and that structural, physical, and chemical changes may be made without departing from the spirit and scope of the present invention. Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. Although any methods and materials similar or equivalent to those described herein can be used in the practice or testing of the present invention, the preferred methods, devices, and materials are now described. [0012] The following abbreviations are used herein: Bu=butyl; HPLC=high-performance liquid chromatography; iPr=isopropyl; Me=methyl; NMR=nuclear magnetic resonance; LCMS (EI)=liquid chromatography mass spectrometry (electron impact) t=tert; and TLC=thin layer chromatography. [0021] Terms not specifically defined herein should be given the meanings that would be given to them by one of skill in the art in light of the disclosure and the context. For example, “C 1-6 alkoxy” is a C 1-6 alkyl with a terminal oxygen, such as methoxy, ethoxy, propoxy, pentoxy and hexoxy. All alkyl, alkylene or alkynyl groups shall be understood as being branched or unbranched where structurally possible and unless otherwise specified. [0022] Other more specific definitions are as follows: [0023] The term “alkyl” refers to a saturated aliphatic radical containing from one to ten carbon atoms or a mono- or polyunsaturated aliphatic hydrocarbon radical containing from two to twelve carbon atoms unless otherwise stated. The mono- or polyunsaturated aliphatic hydrocarbon radical contains at least one double or triple bond, respectively. Examples of “alkyl” include alkyl groups that are straight chain alkyl groups containing from one to eight carbon atoms and branched alkyl groups containing from three to ten carbon atoms. Other examples include lower alkyl groups which are straight chain alkyl groups containing from one to six carbon atoms and branched alkyl groups containing from three to six carbon atoms. It should be understood that any combination term using an “alk” or “alkyl” prefix refers to analogs according to the above definition of “alkyl”. For example, terms such as “alkoxy”, “alkythio” refer to alkyl groups linked to a second group via an oxygen or sulfur atom. “Alkanoyl” refers to an alkyl group linked to a carbonyl group (C═O). Each alkyl or alkyl analog described herein shall be understood to be optionally partially or fully halogenated. [0024] The term “cycloalkyl” refers to the cyclic analog of an alkyl group, as defined above. Examples of cycloalkyl groups are saturated or unsaturated nonaromatic cycloalkyl groups containing from three to eight carbon atoms, and other examples include cycloalkyl groups having three to six carbon atoms. Examples of “cycloalkyl” include, for example, cyclopropyl, cyclopentyl, and cyclohexyl. [0025] The term “heterocycloalkyl” refers to a stable 4-8 membered (but preferably, 5 or 6 membered) monocyclic or 8-11 membered bicyclic heterocycle radical which may be either saturated or unsaturated, and is non-aromatic. Each heterocycle consists of carbon atoms and from 1 to 4 heteroatoms chosen from nitrogen, oxygen and sulfur. The heterocycle may be attached by any atom of the cycle, which results in the creation of a stable structure. Examples of “heterocycloalkyl” include radicals such as pyrrolinyl, pyrrolidinyl, pyrazolinyl, pyrazolidinyl, piperidinyl, morpholinyl, thiomorpholinyl, piperazinyl, indolinyl, azetidinyl, tetrahydropyranyl, tetrahydrothiopyranyl, tetrahydrofuranyl, hexahydropyrimidinyl, hexahydropyridazinyl, dihydro-oxazolyl, 1,2-thiazinanyl-1,1-dioxide, 1,2,6-thiadiazinanyl-1,1-dioxide, isothiazolidinyl-1,1-dioxide and imidazolidinyl-2,4-dione. [0026] The term “halogen” refers to bromine, chlorine, fluorine or iodine. As used herein above and throughout this application, “nitrogen” and “sulfur” include any oxidized form of nitrogen and sulfur and the quaternized form of any basic nitrogen. [0027] The term “aryl” shall be understood to mean a 6-12 membered aromatic carbocycle, which can be a single ring or can be multiple rings fused together or linked covalently. The term “aryl” includes, for example, phenyl and naphthyl; other terms comprising “aryl” will have the same definition for the aryl component, examples of these moieties include: arylalkyl, aryloxy or arylthio. [0028] The term “heteroaryl” refers to a stable 5-8 membered (but preferably, 5 or 6 membered) monocyclic or 8-11 membered bicyclic aromatic heterocycle radical. Each heterocycle consists of carbon atoms and from 1 to 4 heteroatoms chosen from nitrogen, oxygen and sulfur. The heteroaryl group may be attached by any atom of the ring which results in the creation of a stable structure. Examples of “heteroaryl” include radicals such as furanyl, thienyl, pyrrolyl, oxazolyl, thiazolyl, imidazolyl, pyrazolyl, isoxazolyl, isothiazolyl, oxadiazolyl, triazolyl, tetrazolyl, thiadiazolyl, pyridinyl, pyridazinyl, pyrimidinyl, pyrazinyl, indolizinyl, indolyl, isoindolyl, benzofuranyl, benzothienyl, indazolyl, benzimidazolyl, benzthiazolyl, benzoxazolyl, purinyl, quinolizinyl, quinolinyl, isoquinolinyl, cinnolinyl, phthalazinyl, quinazolinyl, quinoxalinyl, naphthyridinyl, pteridinyl, carbazolyl, acridinyl, phenazinyl, phenothiazinyl and phenoxazinyl. [0029] The terms “optional” or “optionally” mean that the subsequently described event or circumstances may or may not occur, and that the description includes instances where the event or circumstance occurs and instances in which it does not. For example, “optionally substituted aryl” means that the aryl radical may or may not be substituted and that the description includes both substituted aryl radicals and aryl radicals having no substitution. [0030] The term “substituted” means that any one or more hydrogens on an atom of a group or moiety, whether specifically designated or not, is replaced with a selection from the indicated group of substituents, provided that the atom's normal valency is not exceeded and that the substitution results in a stable compound. If a bond to a substituent is shown to cross the bond connecting two atoms in a ring, then such substituent may be bonded to any atom on the ring. When a substituent is listed without indicating the atom via which such substituent is bonded to the rest of the compound, then such substituent may be bonded via any atom in such substituent. For example, when the substituent is piperazinyl, piperidinyl, or tetrazolyl, unless specified otherwise, such piperazinyl, piperidinyl, or tetrazolyl group may be bonded to the rest of the compound of the invention via any atom in such piperazinyl, piperidinyl, or tetrazolyl group. Generally, when any substituent or group occurs more than one time in any constituent or compound, its definition on each occurrence is independent of its definition at every other occurrence. Thus, for example, if a group is shown to be substituted with 0 to 2 R, then such group is optionally substituted with up to two R groups and R at each occurrence is selected independently from the defined list of possible R. Such combinations of substituents and/or variables, however, are permissible only if such combinations result in stable compounds. [0031] The present invention relates to a novel strategy for the synthesis of dihydrothieno[3,2-d]pyrimidine diols, and similar pyrimidine-2,4-diols, that provides for higher yields, more efficient reactions, and overcoming many of the prior art problems associated with the large-scale production of dihydrothieno[3,2-d]pyrimidine diols, and similar pyrimidin-2,4-diols. The strategy provides an efficient synthetic scheme that does not require expensive or potentially unstable intermediates, and can be carried out as a “one-pot” reaction if desired. [0032] Methods for making the compounds of the formulas (I) and (X) are described herein. The compounds of the invention may be prepared by the general methods and examples presented below, and additional methods known to those of ordinary skill in the art. Optimum reaction conditions and reaction times may vary depending on the particular reactants used. Unless otherwise specified, solvents, temperatures, pressures, and other reaction conditions may be readily selected by one of ordinary skill in the art. Specific procedures are provided in the Examples section. Reaction progress may be monitored by conventional methods such as TLC or HPLC. Intermediates and products may be purified by methods known in the art, including column chromatography, HPLC or recrystallization. [0033] The preferred methods provide processes of making a dihydrothieno[3,2-d]pyrimidine diol of formula I, e.g.,: [0000] [0000] wherein R 1 and R 2 independently ndependently selected from H, alkyl, cycloalkyl, aryl, heteroaryl, heterocycloalkyl, halogen, alkoxy, aryloxy, cycloalkoxy, heteroaryloxy, heterocycloalkoxy, —NO 2 , —NRR′, haloalkyl, haloalkoxy, —SH, —S-alkyl, —SO 2 -alkyl, —SO 2 NH 2 , —SO 2 NH-alkyl, and —SO 2 N(alkyl) 2 , preferably from H, alkyl, alkoxy, halogen, haloalkyl, haloalkoxy and —NRR′; and wherein R and R′ are H or alkyl. [0034] The preferred methods also provide processes of making 2,4-pyrimidine diols of formula X, e.g.,: [0000] [0000] wherein R 3 and R 4 are independently selected from H, alkyl, cycloalkyl, aryl, heteroaryl, heterocycloalkyl, halogen, alkoxy, aryloxy, cycloalkoxy, heteroaryloxy, heterocycloalkoxy, —NO 2 , —NRR′, haloalkyl, haloalkoxy, —SH, —S-alkyl, —SO 2 -alkyl, —SO 2 NH 2 , —SO 2 NH-alkyl, and —SO 2 N(alkyl) 2 , with the proviso that R 3 , R 4 and R 5 cannot all be H; or [0035] R 3 and R 4 are combined with the carbon atoms to which they are attached to form a ring selected from the group consisting of benzene, pyridine, pyrimidine, pyrazine, cyclohexane, piperidine, piperazine, morpholine, thiomorpholine, a partially or fully hydrated pyrimidine and naphthalene, which optionally may be substituted by a residue selected from among alkyl, cycloalkyl, aryl, heteroaryl, heterocycloalkyl, halogen, alkoxy, aryloxy, cycloalkoxy, heteroaryloxy, heterocycloalkoxy, —NO 2 , —NRR′, haloalkyl, haloalkoxy and hydroxy; [0036] R5 is selected from H, alkyl, cycloalkyl, aryl, heteroaryl, heterocycloalkyl, halogen, alkoxy, aryloxy, cycloalkoxy, heteroaryloxy, heterocycloalkoxy, —NO 2 , —NRR′, haloalkyl, haloalkoxy, —SH, —S-alkyl, —SO 2 -alkyl, —SO 2 NH 2 , —SO 2 NH-alkyl, and —SO 2 N(alkyl) 2 , preferably from H, alkyl, alkoxy, halogen, haloalkyl, haloalkoxy and —NRR′; and [0037] wherein R and R′ are each independently selected from H or alkyl. [0038] As illustrated in Scheme 1, an embodiment of the present invention, compounds of formula I may be prepared starting with an acid-catalyzed condensation between a 3-keto-dihydrothiophene-2-carboxylic acid alkyl ester of formula II, wherein R a is alkyl, and urea (III), to yield a 3-ureido-dihydrothiophene-2-carboxylic acid alkyl ester of formula IV. The compound of formula IV is then cyclized to yield a dihydrothieno[3,2-d]pyrimidine diol of formula I. The cyclization is preferably performed under basic conditions. The condensation and cyclization reactions may be carried out in separate steps, or may be combined in a “one-pot” procedure. The product, a compound of formula I, may be further modified by methods known in the art to produce additional compounds such as dihydrothieno[3,2-d]pyrimidines. [0000] [0039] The condensation reaction of the compounds of formulas II and III takes place in the presence of an acid catalyst, for example, acetic acid, trifluoroacetic acid, perchloric acid, toluene sulfonic acid, hydrobromic acid, hydrochloric acid, sulfuric acid, or nitric acid. In a preferred embodiment, the acid is a hydrochloric acid. An alcohol or mixture of alcohols may be used as a solvent, for example, methanol, ethanol, isopropanol, n-propanol, butanol, etc., may be used. Methanol is the preferred alcoholic solvent. The reaction may be carried out at temperatures between 0° C. and the reflux temperature of the solvent, and generally requires a period of 0.5 to 24 hours for completion, preferably about 2-6 hours, and more preferably about 4-6 or about 3-5 hours. The reaction may be run at ambient pressure, or at reduced or elevated pressures. [0040] The above-described reaction yields a 3-ureido-dihydrothiophene-2-carboxylic acid alkyl ester of formula IV, which may be isolated at this time or may be left in the reaction vessel for a “one-pot” procedure. Isolation may be advantageous when removal of impurities is desired before the cyclization process, but is not required. [0041] Whether isolated or not, the compound of formula IV is cyclized, preferably in the presence of a base, in a suitable solvent such as water or an alcohol, for example, methanol, ethanol, isopropanol, n-propanol, butanol, etc. Non-limiting examples of suitable inorganic bases include metal hydrides (e.g., NaH), metal hydroxides (e.g., NaOH, KOH), metal alkoxides (e.g., MeONa, t-BuOK and Na-tert-amylate), metal carbonates (e.g., Na 2 CO 3 , K 2 CO 3 , Cs 2 CO 3 ), and metal phosphates (e.g., K 3 PO 4 ). In a preferred embodiment, the base is MeONa, and the solvent is methanol. In another preferred embodiment, the base is NaOH and the solvent is water. The reaction may be carried out at temperatures between 0° C. and the reflux temperature of the solvent, and generally requires a period of 0.5 to 24 hours for completion, preferably about 0.5 to 5 hours, and more preferably about 1-3 hours, and even more preferably about 1-2 hours. The reaction may be run at ambient pressure. The above-described reaction yields the dihydrothieno[3,2-d]pyrimidine diol of formula I. [0042] The above-described reaction scheme (Scheme 1) is advantageous over known methods of synthesizing the dihydrothieno[3,2-d]pyrimidine diols of formula I, in that it is higher yielding, more efficient, and more cost-effective because it uses urea, which is inexpensive and freely available, instead of costlier reactants such as s-ethylisothiourea hydrobromide. The present process also avoids the unpleasant stench associated with the release of ethanethiol during known methods. Moreover, the present process provides another advantage in that the 3-ureido-dihydrothiophene-2-carboxylic acid alkyl ester of formula IV is a solid intermediate of enhanced stability, which permits its isolation and long-term storage if desired. [0043] The dihydrothiophene carboxylic acid alkyl ester of formula II may be prepared by methods known in the art. For example, a thiol of formula V and an ester of formula VI may be reacted to form a thioether carboxylic acid alkyl ester of formula VII, which can then be cyclized to form the dihydrothiophene carboxylic acid alkyl ester of formula II. A non-limiting exemplary procedure is shown in Scheme 2. [0000] [0044] As illustrated in Scheme 3, another embodiment of the present invention relates to compounds of formula X that may be prepared starting with an acid-catalyzed condensation between a compound of formula VIII, wherein R a is alkyl, and urea (III), to yield a compound of formula IX. The compound of formula IX is then cyclized to yield a compound of formula X. The cyclization is preferably performed under basic conditions. The condensation and cyclization reactions may be carried out in separate steps, or may be combined in a “one-pot” procedure. The product, a compound of formula X, may be further modified by methods known in the art to produce additional pyrimidine diol compounds. [0000] [0045] The condensation reaction of the compounds of formulas VIII and III takes place in the presence of an acid catalyst, for example, acetic acid, trifluoroacetic acid, perchloric acid, toluene sulfonic acid, hydrobromic acid, hydrochloric acid, sulfuric acid, or nitric acid. In a preferred embodiment, the acid is a hydrochloric acid. An alcohol or mixture of alcohols may be used as a solvent, for example, methanol, ethanol, isopropanol, n-propanol, butanol, etc., may be used. Methanol is the preferred alcoholic solvent. The reaction may be carried out at temperatures between 0° C. and the reflux temperature of the solvent, and generally requires a period of 0.5 to 24 hours for completion, preferably about 2-6 hours, and more preferably about 4-6 or about 3-5 hours. The reaction may be run at ambient pressure, or at reduced or elevated pressures. [0046] The above-described reaction yields a compound of formula IX, which may be isolated at this time or may be left in the reaction vessel for a “one-pot” procedure. Isolation may be advantageous when removal of impurities is desired before the cyclization process, but is not required. [0047] Whether isolated or not, the compound of formula IX is cyclized, preferably in the presence of a base, in a suitable solvent such as water or an alcohol, for example, methanol, ethanol, isopropanol, n-propanol, butanol, etc. Non-limiting examples of suitable inorganic bases include metal hydrides (e.g., NaH), metal hydroxides (e.g., NaOH, KOH), metal alkoxides (e.g., MeONa, t-BuOK and Na-tert-amylate), metal carbonates (e.g., Na 2 CO 3 , K 2 CO 3 , Cs 2 CO 3 ), and metal phosphates (e.g., K 3 PO 4 ). In a preferred embodiment, the base is MeONa, and the solvent is methanol. In another preferred embodiment, the base is NaOH and the solvent is water. The reaction may be carried out at temperatures between 0° C. and the reflux temperature of the solvent, and generally requires a period of 0.5 to 24 hours for completion, preferably about 0.5 to 5 hours, and more preferably about 1-3 hours, and even more preferably about 1-2 hours. The reaction may be run at ambient pressure. The above-described reaction yields a substituted pyrimidine-2,4-diol of formula X. The pyrimidine diols of the above-identified embodiments can be used as intermediates to synthesize pharmaceuticals such as PDE4 inhibitors, by methods known in the art. [0048] In one embodiment of the invention, a process for preparing a compound of formula I: [0000] [0000] comprises: (a) reacting a starting compound of the formula II [0000] [0000] with urea, in the presence of acid, to yield an intermediate of the formula IV [0000] [0000] and (b) cyclizing the intermediate of the formula IV with a base, to yield the final product of the formula I, [0051] wherein R 1 and R 2 are independently selected from H, alkyl, cycloalkyl, aryl, heteroaryl, heterocycloalkyl, halogen, alkoxy, aryloxy, cycloalkoxy, heteroaryloxy, heterocycloalkoxy, —NO 2 , —NRR′, haloalkyl, haloalkoxy, —SH, —S-alkyl, —SO 2 -alkyl, —SO 2 NH 2 , —SO 2 NH-alkyl, and —SO 2 N(alkyl) 2 ; [0052] wherein R and R′ are each independently selected from H or alkyl; and [0053] wherein R a is selected from the group consisting of H, halogen, alkyl, and aryl. [0054] In a preferred embodiment, R 1 and R 2 are independently selected from H, alkyl, aryl, alkoxy, halogen, haloalkyl, haloalkoxy and —NRR′, wherein R and R′ are each independently selected from H or alkyl. [0055] In yet another preferred embodiment, the compound of formula I is 6,7-dihydro-thieno[3,2-d]pyrimidine-2,4-diol,6-methyl-6,7-dihydro-thieno[3,2-d]pyrimidine-2,4-diol,6-ethyl-6,7-dihydro-thieno[3,2-d]pyrimidine-2,4-diol, 6-phenyl-6,7-dihydro-thieno[3,2-d]pyrimidine-2,4-diol, 6,6-dimethyl-6,7-dihydro-thieno[3,2-d]pyrimidine-2,4-diol, or 7-methyl-6,7-dihydro-thieno[3,2-d]pyrimidine-2,4-diol. [0056] In another embodiment of the invention, a process for preparing a compound of formula X: [0000] [0000] comprises: (a) reacting a starting compound of the formula VIII [0000] [0000] with urea, in the presence of acid, to yield an intermediate of the formula IX [0000] [0000] and (b) cyclizing the intermediate of the formula IX with a base, to yield the final product of the formula X, [0059] wherein R 3 and R 4 are independently selected from H, alkyl, cycloalkyl, aryl, heteroaryl, heterocycloalkyl, halogen, alkoxy, aryloxy, cycloalkoxy, heteroaryloxy, heterocycloalkoxy, —NO 2 , —NRR′, haloalkyl, haloalkoxy, —SH—, —S-alkyl, —SO 2 -alkyl, —SO 2 NH 2 , —SO 2 NH-alkyl, and —SO 2 N(alkyl) 2 , with the proviso that R 3 and R 4 cannot both be H; or [0060] R 3 and R 4 are combined with the carbon atoms to which they are attached to form a ring selected from the group consisting of benzene, pyridine, pyrimidine, pyrazine, cyclohexane, piperidine, piperazine, morpholine, thiomorpholine, a partially or fully hydrated pyrimidine and naphthalene, which optionally may be substituted by a residue selected from among alkyl, cycloalkyl, aryl, heteroaryl, heterocycloalkyl, halogen, alkoxy, aryloxy, cycloalkoxy, heteroaryloxy, heterocycloalkoxy, —NO 2 , —NRR′, haloalkyl, haloalkoxy and hydroxy; [0061] wherein R 5 is selected from H, alkyl, cycloalkyl, aryl, heteroaryl, heterocycloalkyl, halogen, alkoxy, aryloxy, cycloalkoxy, heteroaryloxy, heterocycloalkoxy, —NO 2 , —NRR′, haloalkyl, haloalkoxy, —SH, —S-alkyl, —SO 2 -alkyl, —SO 2 NH 2 , —SO 2 NH-alkyl, and —SO 2 N(alkyl) 2 ; [0062] wherein R and R′ are each independently selected from H or alkyl; and [0063] wherein R a is selected from the group consisting of H, halogen, alkyl and aryl. [0064] In a preferred embodiment, the compound of formula X is 9H-indeno[2,1-d]pyrimidine-2,4-diol. [0065] Preferably, R a in the above outlined processes is an alkyl selected from methyl, ethyl, propyl, isopropyl, butyl, isobutyl, sec-butyl or tert-butyl. [0066] Additionally, the acid may be selected from acetic acid, trifluoroacetic acid, perchloric acid, toluene sulfonic acid, hydrobromic acid, hydrochloric acid, sulfuric acid and nitric acid. Preferably, the acid is hydrochloric acid. The base may be selected from the group consisting of metal hydride bases, metal hydroxide bases, metal carbonates, metal alkoxide bases, and metal phosphate bases. Preferably, the base is MeONa or NaOH. [0067] Preferably, in the above outlined processes, the intermediate of the formula IV or formula IX is isolated before cyclizing it in step (b). The isolated intermediate of the formula IV or formula IX is purified by a method known in the art, including column chromatography, HPLC or recrystallization. Alternatively, the intermediate of the formula IV or formula IX is not isolated before cyclizing it in step b). [0068] In another embodiment, the solvent of the step (a) in the above-outlined processes is an alcohol or a mixture of alcohols. The alcohol or mixture of alcohols may be methanol, ethanol, isopropanol, n-propanol, butanol or mixtures thereof. In yet another embodiment, the reaction outlined in step (a) of the above processes is carried out at a temperature between 0° C. and reflux temperature of the solvent, and between 0.5 hour and 24 hours for its completion. [0069] In another embodiment, the solvent of the step (b) in the above-outlined processes is water, an alcohol or a mixture of alcohols. The alcohol or mixture of alcohols may be methanol, ethanol, isopropanol, n-propanol, butanol or mixtures thereof. In yet another embodiment, the cyclization reaction outlined in step (b) of the above processes is carried out at a temperature between 0° C. and reflux temperature of the solvent, and between 0.5 hour and 24 hours for completion. EXAMPLES Example 1 [0070] Compound III (urea; 2 equiv.) was charged into a flask equipped with a stirrer, N 2 line and thermocouple thermometer followed by methanol (3 mL/g of compound IIa) and compound IIa (1 equiv) (see Scheme 4). Conc. HCl (0.2 equiv) was charged at 20-25° C. and the mixture was stirred at reflux for 4 hours. NaOMe (1.2 equiv., 25% solution in MeOH) was charged at 0° C. and the above mixture was stirred at reflux for 1.5 hours and then cooled to 0° C. Conc. HCl was added dropwise until the pH of the solution was 2-3, the mixture was stirred for 5-10 min and the resulting solid was collected by filtration. The cake was washed thoroughly with water, air-dried for 2-3 hours (suction) and then dried further in a vacuum oven at 50° C. for 12-16 hours to afford compound Ia in 80-85% yield from compound IIa. [0000] Example 2 3-Ureido-4,5-dihydro-thiophene-2-carboxylic acid methyl ester [0071] Compound III (urea; 2 equiv.) was charged into a vessel equipped with a stirrer, N 2 line and thermocouple thermometer followed by methanol (1.5 to 2 mL/g of compound IIa) and compound IIa (1 equiv) (see Scheme 5). Conc. HCl (0.2 equiv) was charged at 20-25° C. and the mixture stirred at reflux for 4-6 hours. The reaction mixture was cooled to 0° C. and the resulting solid was collected by filtration. The cake was washed with water (twice with 1 mL/g of compound IIa) to afford compound IVa as a white solid in 95% yield. [0000] [0000] 95% yield, 1 H NMR (500 MHz, (CD 3 ) 2 SO) δ 3.10 (dd, 2H, J=8.5, 8.5 Hz), 3.50 (dd, 2H, J=8.5, 8.5 Hz), 3.73 (s, 3H), 6.50-7.20 (bs, 2H), 9.47 (s, 1H); 13 C NMR (125 MHz, (CD 3 ) 2 SO) δ 28.7, 37.8, 52.4, 100.0, 151.6, 154.7, 165.7; LCMS (EI) for C 7 H 11 N 2 O 3 S, (M+H)+calcd. 203.0, measd. 203.0. 6,7-Dihydro-thieno[3,2-d]pyrimidine-2,4-diol [0072] Compound IVa was added to a solution of water (3 mL/mL of compound IVa) and NaOH at ambient temperature. The above mixture was stirred at 85° C. for 1.5 hours. After cooling to 0° C., conc. HCl (approximately 1.1 equiv.) was added slowly until the pH of the solution was 0-1. The mixture was cooled to 0° C., stirred for 5-10 min and the resulting solid was collected by filtration. The cake was washed thoroughly with water twice (0.5 mL/g of compound IVa), air-dried for 2-3 hours (suction) and then dried further in a vacuum oven at 50° C. for 12-16 hours to afford compound Ia as a white solid in 95% yield from compound IVa. [0000] [0000] 95% yield, 1 H NMR (500 MHz, (CD 3 ) 2 SO) δ 3.11 (dd, 2H, J=8.5, 8.5 Hz), 3.31 (dd, 2H, J=8.5, 8.5 Hz), 11.14 (s , 1H), 11.38 (s, 1H); 13 C NMR (125 MHz, (CD 3 ) 2 SO) δ 29.3, 35.4, 108.5, 150.5, 152.4, 160.4; LCMS (EI) for C 6 H 7 N 2 O 2 S, (M+H)+ calcd. 171.0, measd. 171.0. [0000] Example 3 5-Methyl-3-ureido-4,5-dihydro-thiophene-2-carboxylic acid methyl ester [0073] Compound III (urea; 2 equiv.) was charged into a vessel equipped with a stirrer, N 2 line and thermocouple thermometer followed by methanol (1.5 to 2.0 mL/g of compound IIb) and compound IIb (1 equiv) (see Scheme 6). Conc. HCl (0.2 equiv) was charged at 20-25° C. and the mixture stirred at reflux for 4-6 hours. The reaction mixture was cooled to 0° C. and the resulting solid was collected by filtration. The cake was washed with water (twice with 1 mL/g of compound IIb) to afford compound IVb as a white solid in 93% yield. [0000] [0000] 93% yield, 1 H NMR (400 MHz, (CD 3 ) 2 SO) δ 1.32 (d, 3H, J=6.5 Hz), 3.24 (dd, 1H, J=6.5, 18.0 Hz), 3.55-3.73 (m, 2H), 3.72 (s, 3H), 6.40-7.30 (bs, 1H), 9.35-9.65 (bs, 1H); 13 C NMR (100 MHz, (CD 3 ) 2 SO) δ 22.8, 40.1, 45.6, 52.3, 99.5, 150.0, 154.7, 165.8; LCMS (EI) for C 8 H 13 N 2 O 3 S, (M+H)+ calcd. 217.1, measd. 217.6. 6-Methyl-6,7-dihydro-thieno[3,2-d]pyrimidine-2,4-diol [0074] Compound IVb was added to a solution of water (3 mL/mL of compound IVb) and NaOH at ambient temperature. The above mixture was stirred at 85° C. for 1.5 hours. After cooling to 0° C., conc. HCl (approximately 1.1 equiv.) was added slowly until the pH of the solution was 0-1. The mixture was cooled to 0° C., stirred for 5-10 min and the resulting solid was collected by filtration. The cake was washed thoroughly with water twice (0.5 mL/g of compound IVb), air-dried for 2-3 hours (suction) and then dried further in a vacuum oven at 50° C. for 12-16 hours to afford compound Ib as a white solid in 90% yield from compound IVb. [0000] [0000] 90% yield, 1 H NMR (400 MHz, (CD 3 ) 2 SO) δ 1.39 (d, 3H, J=6.5 Hz), 2.75 (dd, 1H, J=6.5, 17.0 Hz), 3.26 (dd, 1H, J=8.5, 17.0 Hz), 3.96 (dddd, 1H, J=6.5, 6.5, 6.5, 13.0 Hz), 11.00-11.20 (bs, 1H), 11.20-11.40 (bs, 1H); 13 C NMR (100 MHz, (CD 3 ) 2 SO) δ 23.0, 42.0, 43.0, 108.0, 149.0, 152.4, 160.4; LCMS (EI) for C 7 H 9 N 2 O 2 S, (M+H)+ calcd. 185.0, measd. 185.1. [0000] Example 4 5-Ethyl-3-ureido-4,5-dihydro-thiophene-2-carboxylic acid methyl ester [0075] Compound III (urea; 2 equiv.) was charged into a vessel equipped with a stirrer, N 2 line and thermocouple thermometer followed by methanol (1.5 to 2 mL/g of compound IIc) and compound IIc (1 equiv) (see Scheme 7). Conc. HCl (0.2 equiv) was charged at 20-25° C. and the mixture stirred at reflux for 4-6 hours. The reaction mixture was cooled to 0° C. and the resulting solid was collected by filtration. The cake was washed with water (twice with 1 mL/g of compound IIc) to afford compound IVc as a white solid in 93% yield. [0000] [0076] 93% yield, 1 H NMR (500 MHz, (CD 3 ) 2 SO) δ 0.93 (t, 3H, J=7.3 Hz), 1.52-1.74 (m, 2H), 3.28 (dd, 1H, J=6.5, 18.0 Hz), 3.53 (dddd, 1H, J=6.0, 6.0, 8.5, 8.5 Hz), 3.61 (dd, 1H, J=8.5, 18.0 Hz), 3.72 (s, 3H), 6.83 (bs, 2H), 9.44 (s, 1H); 13 C NMR (100 MHz, (CD 3 ) 2 SO) δ 12.8, 29.7, 43.5, 47.3, 52.3, 99.3, 150.3, 154.7, 165.7; LCMS (EI) for C 9 H 15 N 2 O 3 S, (M+H)+ calcd. 231.1, measd. 231.1. 6-Ethyl-6,7-dihydro-thieno[3,2-d]pyrimidine-2,4-diol [0077] Compound IVc was added to a solution of water (3 mL/mL of compound IVc) and NaOH at ambient temperature. The above mixture was stirred at 85° C. for 1.5 hours. After cooling to 0° C., conc. HCl (approximately 1.1 equiv.) was added slowly until the pH of the solution was 0-1. The mixture was cooled to 0° C., stirred for 5-10 min and the resulting solid was collected by filtration. The cake was washed thoroughly with water twice (0.5 mL/g of compound IVc), air-dried for 2-3 hours (suction) and then dried further in a vacuum oven at 50° C. for 12-16 hours to afford compound Ic as a white solid in 74% yield from compound IVc. [0000] [0000] 74% yield, 1 H NMR (500 MHz, (CD 3 ) 2 SO) δ 0.95 (t, 3H, J=7.3 Hz), 1.60-1.80 (m, 2H), 2.81 (dd, 1H, J=7.0, 17.3 Hz), 3.24 (dd, 1H, J=8.5, 17.3 Hz), 3.61 (dddd, 1H, J=7.0, 7.0, 8.5, 8.5 Hz), 11.10 (s, 1H), 11.31 (s, 1H); 13 C NMR (100 MHz, (CD 3 ) 2 SO) δ 12.8, 29.8, 40.9, 49.1, 107.7, 149.2, 152.3, 160.3; LCMS (EI) for C 8 H 11 N 2 O 2 S, (M+H)+ calcd. 199.1, measd. 199.1. [0000] Example 5 5-Phenyl-3-ureido-4,5-dihydro-thiophene-2-carboxylic acid methyl ester [0078] Compound III (urea; 2 equiv.) was charged into a vessel equipped with a stirrer, N 2 line and thermocouple thermometer followed by methanol (1.5 to 2 mL/g of compound IId) and compound IId (1 equiv) (see Scheme 8). Conc. HCl (0.2 equiv) was charged at 20-25° C. and the mixture stirred at reflux for 4-6 hours. The reaction mixture was cooled to 0° C. and the resulting solid was collected by filtration. The cake was washed with water (twice with 1 mL/g of compound IId) to afford compound IVd as a white solid in 97% yield. [0000] [0000] 97% yield, 1 H NMR (500 MHz, (CD 3 ) 2 SO) δ 3.70 (dd, 1H, J=8.0, 18.0 Hz), 3.74 (s, 3H), 3.92 (dd, 1H, J=8.0, 18.0 Hz), 4.87 (dd, 1H, J=8.0, 8.0 Hz), 6.60-7.20 (bs, 2H), 7.25-7.50 (m, 5H), 9.51 (s, 1H); 13 C NMR (100 MHz, (CD 3 ) 2 SO) δ 45.1, 48.1, 52.4, 99.4, 127.8, 128.3, 129.5, 142.8, 149.5, 154.7, 165.4 (missing 2 signals due to overlap); LCMS (EI) for C 13 H 15 N 2 O 3 S, (M+H)+ calcd. 279.1, measd. 279.1. 6-Phenyl-6,7-dihydro-thieno[3,2-d]pyrimidine-2,4-diol [0079] Compound IVd was added to a solution of water (3 mL/mL of compound IVd) and NaOH at ambient temperature. The above mixture was stirred at 85° C. for 1.5 hours. After cooling to 0° C., conc. HCl (approximately 1.1 equiv.) was added slowly until the pH of the solution was 0-1. The mixture was cooled to 0° C., stirred for 5-10 min and the resulting solid was collected by filtration. The cake was washed thoroughly with water twice (0.5 mL/g of compound IVd), air-dried for 2-3 hours (suction) and then dried further in a vacuum oven at 50° C. for 12-16 hours to afford compound Id as a white solid in 89% yield from compound IVd. [0000] [0000] 89% yield, 1 H NMR (500 MHz, (CD 3 ) 2 SO) 3.29 (dd, 1H, J=8.5, 17.5 Hz), 3.51 (dd, 1H, J=8.5, 17.5 Hz), 5.17 (dd, 1H, J=8.5, 8.5 Hz), 7.30-7.50 (m, 5H), 11.20 (s, 1H), 11.42 (s, 1H); 13 C NMR (125 MHz, (CD 3 ) 2 SO) δ 42.7, 49.6, 107.8, 128.0, 128.7, 129.6, 142.0, 148.5, 152.3, 160.1 (missing 2 signals due to overlap); LCMS (EI) for C 12 H 11 N 2 O 2 S, (M+H)+ calcd. 247.1, measd. 247.1. [0000] Example 6 5,5-Dimethyl-3-ureido-4,5-dihydro-thiophene-2-carboxylic acid methyl ester [0080] Compound III (urea; 2 equiv.) was charged into a vessel equipped with a stirrer, N 2 line and thermocouple thermometer followed by methanol (1.5 to 2 mL/g of compound IIe) and compound IIe (1 equiv) (see Scheme 9). Conc. HCl (0.2 equiv) was charged at 20-25° C. and the mixture stirred at reflux for 4-6 hours. The reaction mixture was cooled to 0° C. and the resulting solid was collected by filtration. The cake was washed with water (twice with 1 mL/g of compound IIe) to afford compound IVe as a white solid in 83% yield. [0000] [0000] 83% yield, 1 H NMR (400 MHz, (CD 3 ) 2 SO) δ 1.46 (s, 6H), 3.38 (s , 2H), 3.71 (s, 3H), 6.60-7.20 (bs, 2H), 9.45 (s, 1H); 13 C NMR (100 MHz, (CD 3 ) 2 SO) δ 30.4, 51.6, 52.0, 52.3, 100.2, 149.5, 154.8, 165.8 (1 signal missing due to overlap); LCMS (EI) for C 9 H 15 N 2 O 3 S, (M+H)+ calcd. 231.1, measd. 231.6. 6,6-Dimethyl-6,7-dihydro-thieno[3,2-d]pyrimidine-2,4-diol [0081] Compound IVe was added to a solution of water (3 mL/mL of compound IVe) and NaOH at ambient temperature. The above mixture was stirred at 85° C. for 1.5 hours. After cooling to 0° C., conc. HCl (approximately 1.1 equiv.) was added slowly until the pH of the solution was 0-1. The mixture was cooled to 0° C., stirred for 5-10 min and the resulting solid was collected by filtration. The cake was washed thoroughly with water twice (0.5 mL/g of compound IVe), air-dried for 2-3 hours (suction) and then dried further in a vacuum oven at 50° C. for 12-16 hours to afford compound Ie as a white solid in 90% yield from compound IVe. [0000] [0000] 90% yield, 1 H NMR (400 MHz, (CD 3 ) 2 SO) δ 1.53 (s, 6H), 2.95 (s, 2H), 11.10 (s, 1H), 11.32 (s, 1H); 13 C NMR (100 MHz, (CD 3 ) 2 SO) δ 30.7, 49.2, 54.7, 108.4, 148.2, 152.3, 160.5 (1 signal missing due to overlap); LCMS (EI) for C 8 H 11 N 2 O 2 S, (M+H)+calcd. 199.1, measd. 199.1. [0000] Example 7 4-Methyl-3-ureido-4,5-dihydro-thiophene-2-carboxylic acid methyl ester [0082] Compound III (urea; 2 equiv.) was charged into a vessel equipped with a stirrer, N 2 line and thermocouple thermometer followed by methanol (1.5 to 2 mL/g of compound IIf) and compound IIf (1 equiv) (see Scheme 10). Conc. HCl (0.2 equiv) was charged at 20-25° C. and the mixture stirred at reflux for 4-6 hours. The reaction mixture was cooled to 0° C. and the resulting solid was collected by filtration. The cake was washed with water (twice with 1 mL/g of compound IIf) to afford compound IVf as a white solid in 48% yield. [0000] [0000] 48% yield, 1 H NMR (500 MHz, (CD 3 ) 2 SO) δ 1.16 (d, 3H, J=7.0 Hz), 2.75 (d, 1H, J=11.0 Hz), 3.20 (dd, 1H, J=7.5, 11.0 Hz), 3.73 (s, 3H), 4.35-4.43 (m, 1H), 6.50-7.20 (m, 2H), 9.40 (s, 1H); 13 C NMR (125 MHz, (CD 3 ) 2 SO) δ 16.7, 36.0, 42.0, 52.4, 98.8, 154.3, 155.7, 166.0; LCMS (EI) for C 8 H 13 N 2 O 3 S, (M+H)+ calcd. 217.1, measd. 217.1. 7-Methyl-6,7-dihydro-thieno[3,2-d]pyrimidine-2,4-diol [0083] Compound IVf was added to a solution of water (3 mL/mL of compound IVf) and NaOH at ambient temperature. The above mixture was stirred at 85° C. for 1.5 hours. After cooling to 0° C., conc. HCl (approximately 1.1 equiv.) was added slowly until the pH of the solution was 0-1. The mixture was cooled to 0° C., stirred for 5-10 min and the resulting solid was collected by filtration. The cake was washed thoroughly with water twice (0.5 mL/g of compound IVf), air-dried for 2-3 hours (suction) and then dried further in a vacuum oven at 50° C. for 12-16 hours to afford compound If as a white solid in 89% yield from compound IVf. [0000] [0000] 89% yield, 1 H NMR (500 MHz, (CD 3 ) 2 SO) δ 1.26 (d, 3H, J=7.0 Hz), 2.92 (dd, 1H, J=5.0, 11.0 Hz), 3.34-3.42 (m, 1H), 3.52 (dd, 1H, J=8.5, 11.0 Hz), 11.17 (s , 1H), 11.34 (s, 1H); 13 C NMR (125 MHz, (CD 3 ) 2 SO) δ 17.2, 36.9, 42.3, 107.5, 152.7, 153.7, 160.6; LCMS (EI) for C 7 H 9 N 2 O 2 S, (M+H)+ calcd. 185.0, measd. 185.2. [0000] Example 8 2-Ureido-cyclopent-1-enecarboxylic acid methyl ester [0084] Compound III (urea; 2 equiv.) was charged into a vessel equipped with a stirrer, N 2 line and thermocouple thermometer followed by methanol (1.5 to 2 mL/g of compound VIIIa) and compound VIIIa (1 equiv) (see Scheme 11). Conc. HCl (0.2 equiv) was charged at 20-25° C. and the mixture stirred at reflux for 4-6 hours. The reaction mixture was cooled to 0° C. and the resulting solid was collected by filtration. The cake was washed with water (twice with 1 mL/g of compound VIIIa) to afford compound IXa as a white solid in 100% yield. [0000] [0000] 100% yield, 1 H NMR (400 MHz, (CD 3 ) 2 SO) δ 1.79 (dt, 2H, J=7.6, 7.6 Hz), 2.43 (t, 2H, J=7.6 Hz), 3.06 (t, 2H, J=7.6 Hz), 3.68 (s, 3H), 6.5-7.0 (bs, 2H), 9.44 (s, 1H); 13 C NMR (100 MHz, (CD 3 ) 2 SO) δ 21.6, 29.0, 34.9, 51.4, 102.3, 155.1, 157.9, 167.8; LCMS (EI) for C 8 H 13 N 2 O 3 , (M+H)+calcd. 184.1, measd. 185.0. 6,7-Dihydro-5H-cyclopentapyrimidine-2,4-diol [0085] Compound IXa was added to a solution of water (3 mL/mL of compound IXa) and NaOH at ambient temperature. The above mixture was stirred at 85° C. for 1.5 hours. After cooling to 0° C., conc. HCl (approximately 1.1 equiv.) was added slowly until the pH of the solution was 0-1. The mixture was cooled to 0° C., stirred for 5-10 min and the resulting solid was collected by filtration. The cake was washed thoroughly with water twice (0.5 mL/g of compound IXa), air-dried for 2-3 hours (suction) and then dried further in a vacuum oven at 50° C. for 12-16 hours to afford compound Xa as a white solid in 99% yield from compound IXa. [0000] [0000] 99% yield, 1 H NMR (500 MHz, (CD 3 ) 2 SO) δ 1.99 (dt, 2H, J=7.5, 7.5 Hz), 2.48 (t, 2H, J=7.5 Hz), 2.67 (t, 2H, J=7.5 Hz), 10.70 (bs, 1H), 11.05 (bs, 1H); 13 C NMR (100 MHz, (CD 3 ) 2 SO) δ 21.9, 27.3, 31.9, 110.5, 153.2, 157.0, 162.9; LCMS (EI) for C 7 H 9 N 2 O 2 , (M+H)+ calcd. 153.1, measd. 153.3. [0000] Example 9 2-Ureido-3H-indene-1-carboxylic acid methyl ester [0086] Compound III (urea; 2 equiv.) was charged into a vessel equipped with a stirrer, N 2 line and thermocouple thermometer followed by methanol (1.5 to 2 mL/g of compound VIIIb) and compound VIIIb (1 equiv) (see Scheme 11). Conc. HCl (0.2 equiv) was charged at 20-25° C. and the mixture stirred at reflux for 4-6 hours. The reaction mixture was cooled to 0° C. and the resulting solid was collected by filtration. The cake was washed with water (twice with 1 mL/g of compound VIIIb) to afford compound IXb as a white solid in 72% yield. [0000] [0000] 72% yield, 1 H NMR (500 MHz, (CD 3 ) 2 SO) δ 3.91 (s, 3H), 4.21 (s, 2H), 6.8-7.4 (bs, 2H), 7.09 (ddd, 1H, J=1.5,7.5, 7.5 Hz), 7.25 (ddd, 1H, J=1.5,7.5, 7.5 Hz), 7.40 (d, 1H, J=7.5 Hz), 7.71 (d, 1H, J=7.5 Hz), 10.00 (bs, 1H); 13 C NMR (100 MHz, (CD 3 ) 2 SO) δ 40.5, 51.9, 105.4, 120.9, 123.8, 124.1, 127.3, 137.1, 140.6, 154.8, 161.5, 167.0; LCMS (EI) for C 12 H 13 N 2 O 3 , (M+H)+ calcd. 233.1, measd. 233.2. 9H-Indeno[2,1-d]pyrimidine-2,4-diol [0087] Compound IXb was added to a solution of water (3 mL/mL of compound IXb) and NaOH at ambient temperature. The above mixture was stirred at 85° C. for 1.5 hours. After cooling to 0° C., conc. HCl (approximately 1.1 equiv.) was added slowly until the pH of the solution was 0-1. The mixture was cooled to 0° C., stirred for 5-10 min and the resulting solid was collected by filtration. The cake was washed thoroughly with water twice (0.5 mL/g of compound IXb), air-dried for 2-3 hours (suction) and then dried further in a vacuum oven at 50° C. for 12-16 hours to afford compound Xb as a white solid in 93% yield from compound IXb. [0000] [0000] 93% yield, 1 H NMR (500 MHz, (CD 3 ) 2 SO) δ 3.84 (s, 3H), 7.18 (dd, 1H, J=7.5, 7.5 Hz), 7.31 (dd, 1H, J=7.5, 7.5 Hz), 7.47 (d, 1H, J=7.5 Hz), 7.73 (d, 1H, J=7.5 Hz), 11.13 (bs, 1H), 11.79 (bs, 1H); 13 C NMR (100 MHz, (CD 3 ) 2 SO) δ 36.6, 111.6, 120.3, 125.0, 125.1, 127.8, 137.6, 139.6, 152.4, 160.0, 161.3; LCMS (EI) for C 11 H 9 N 2 O 2 , (M+H)+ calcd. 201.1, measd. 201.1. [0000] [0088] The above description, drawings and examples are only illustrative of preferred embodiments which achieve the objects, features and advantages of the present invention. It is not intended that the present invention be limited to the illustrative embodiments. Any modification of the present invention which comes within the spirit and scope of the following claims should be considered part of the present invention.

The present invention relates to an improved process for the preparation of dihydrothieno[3,2-d]pyrimidine diols, and similar pyrimidine diols, that is efficient, high-yielding, and does not require expensive and potentially unstable intermediates. The diols are used as intermediates in the synthesis of pyrimidine compounds which inhibit PDE4, and are thus useful in the treatment of respiratory or gastrointestinal diseases and complaints, peripheral or central nervous system diseases and disorders, inflammatory conditions, and cancers.

INCORPORATION BY REFERENCE/CROSS-REFERENCE TO RELATED APPLICATIONS [0001] This application is a continuation of U.S. Pat. No. 9,118,304, filed on Jan. 31, 2013, and issued on Aug. 25, 2015, which claims the benefit under 35 U.S.C. §119(e) of U.S. Provisional Application No. 61/652,694, filed on May 29, 2012, both of which are hereby incorporated herein by reference in their entirety. BACKGROUND OF THE INVENTION [0002] Television programming is broadcast by broadcasting entities on different television channels. Some examples of well-known television networks in the United States include ABC, CBS, FOX, NBC, and PBS. [0003] In general, the channels map to frequency ranges within the radio frequency (RF) spectrum. For example, in the United States channel 2 is broadcast between 54-60 MegaHertz (MHz), channel 3 is broadcast between 60-66 MHz, and channel 4 is broadcast between 66-72 MHz, to list a few examples. [0004] Recently, systems having arrays of small RF antenna elements have been deployed for capturing the over the air content. The systems then stream the captured content to users via public networks, such as the Internet, and/or private networks. An example of a system for capturing and streaming over the air content to users via the Internet is described in, “System and Method for Providing Network Access to Antenna Feeds” by Kanojia et al., filed Nov. 17, 2011, U.S. patent application Ser. No. 13/299,186, (U.S. Pat. Pub. No. US 2012/0127374 A1), which is incorporated herein by reference in its entirety. [0005] In these capture systems, each user is assigned their own antenna element. Thus, the systems generally include arrays having large numbers of physically small antenna elements. In order to maximize the number of antenna elements at installation locations, the antenna elements are implemented on antenna array cards in two dimensional arrays and are preferably deployed in three dimensional arrays. Generally, the three dimensional arrays are created by stacking the antenna array cards. SUMMARY OF THE INVENTION [0006] Because the antenna elements are physically small and the arrays are preferably dense, the capture systems should be located physically near to television transmitters of the broadcasting entities. This ensures a strong signal and compensates for the low gain characteristics of the physically small antenna elements and any other attenuation effects due to the density of the arrays. Additionally, in arrays where there is limited (or no) a priori knowledge of frequency, phasing, or amplitude, the design and configuration of the array is unable to account for coupling (or interference) between antenna elements. [0007] Unlike antenna elements in a phased array, it is not desirable to have multiple antenna elements competing over the same incident power. To minimize coupling between antenna elements, users are not assigned randomly to antenna elements within the array. Instead, they are selectively assigned to antenna elements based on which channels are requested by the users and to which channels the other antenna elements are already tuned. [0008] Despite attempts to minimize coupling between antenna elements, at least some coupling is unavoidable due to the array density. The present system is directed to dynamically tuning antenna elements to enhance reception and reduce coupling of the antenna elements in the array. By implementing tuning controls, the antenna elements can be tuned based on measured parameters to reduce destructive effects due to coupling between the antenna elements. [0009] In general, according to one aspect, the invention features a method for dynamically tuning antenna elements. The method comprises receiving requests to capture over the air broadcasts, selecting an antenna element from a group of available antenna elements to capture one of the requested over the air broadcasts, and dynamically tuning the selected antenna element to enhance reception of one of the requested over the air broadcasts. [0010] In embodiments, the method further comprises measuring parameters of the selected antenna element to determine how to optimize the selected antenna element. The parameters typically include received power, signal quality, temperature of the antenna element, and/or automatic gain control, which can be prioritized. Preferably the method further comprises adjusting a control voltage of a varactor diode pair based on the measured parameters to tune the selected antenna element. [0011] In examples, an optimization algorithm is used to yield a divergence of the measured parameters. The optimization algorithm can be a conjugate gradient algorithm, mapping techniques, or ad hoc algorithm. [0012] Impedances matching is also preferably employed between the antenna elements and tuners with impedance matching circuits. [0013] In some cases parameter limits are applied to prevent dynamically tuning antenna elements above a distance threshold or above a frequency threshold. [0014] In other examples, the method may further comprise maintaining the tuning of the selected antenna element until the received request is released. In some instances this release may be related to a time attribute associated with a request to capture over the air broadcasts, wherein the time attribute identifies at least a broadcast expiration time. In this instance, the method may further automatically release the selected antenna element after the broadcast expiration time. In some examples, the time attribute may further identify a broadcast start time, in which case selecting the antenna element from the group of available antenna elements may automatically occur before the broadcast start time. [0015] In still other examples, the method may further comprise recording the one of the requested over the air broadcasts into a memory associated with an end-user that submitted a request to capture the one of the requested over the air broadcasts. The method may still further include transcoding the captured one of the requested over the air broadcasts into a format that is more efficient for storage than the over the air broadcast format. In other examples, the method may comprise transcoding the captured one of the requested over the air broadcasts into a format that is more efficient for streaming to the end-user than the over the air broadcast format. [0016] In general, according to another aspect, the invention features an antenna element tuning system, comprising a web server that receives requests to capture over the air broadcasts from broadcasting entities and an antenna controller that selects an antenna element from a group of available antenna elements to capture the requested over the air broadcasts and then dynamically tunes the antenna element to enhance reception of the one of the requested over the air broadcasts. In certain instances, the system may measure parameters of the selected antenna element to optimize the selected antenna element. The measured parameters may be selected from the group comprising received power, signal quality, temperature of the antenna element, and automatic gain control. These measured parameters may be used to adjust a varactor diode pair that may be part of the system. [0017] In some examples, the system may comprise a timer operably connected to the antenna controller such that the selected antenna element is automatically released after the expiration time of the one of the requested over the air broadcasts. This timer may be a countdown timer and may be connected to the antenna controller such that the selected antenna element is tuned and released based on the timing of the one of the requested over the air broadcasts. Alternatively, the timer may be a real time clock in which case the timing of antenna tuning, recording, and/or streaming may be based on actual time. [0018] The system in some instances may further include memory for storing the one of the request over the air broadcasts. In still other examples, the system may still further include a transcoder to convert the captured one of the requested over the air broadcasts into a format that is more efficient for storage than the over the air broadcast format. Alternatively, a transcoder may be included in the system to convert the captured one of the requested over the air broadcasts into a format that is more efficient for streaming to the end-user than the over the air broadcast format. [0019] The above and other features of the invention including various novel details of construction and combinations of parts, and other advantages, will now be more particularly described with reference to the accompanying drawings and pointed out in the claims. It will be understood that the particular method and device embodying the invention are shown by way of illustration and not as a limitation of the invention. The principles and features of this invention may be employed in various and numerous embodiments without departing from the scope of the invention. BRIEF DESCRIPTION OF THE DRAWINGS [0020] In the accompanying drawings, reference characters refer to the same parts throughout the different views. The drawings are not necessarily to scale; emphasis has instead been placed upon illustrating the principles of the invention. Of the drawings: [0021] FIG. 1 is a block diagram illustrating a system for the capture and distribution of broadcast television programs. [0022] FIG. 2 is a schematic perspective view of a three dimensional antenna array including a card cage structure shown in phantom, which functions as an enclosure for the antenna array cards. [0023] FIG. 3A is a circuit diagram of an antenna and tuning feed network for an antenna system. [0024] FIG. 3B is an alternative embodiment of the circuit diagram and tuning feed network for the antenna system. [0025] FIG. 4 is a flowchart illustrating the steps the antenna optimize and control system performs to dynamically tune a single antenna element. [0026] FIG. 5 is a flowchart illustrating the steps the antenna optimize and control system performs to dynamically tune antenna elements where there is no a priori knowledge of the antenna elements. [0027] FIG. 6 is a flowchart illustrating the steps the antenna optimize and control system performs to dynamically tune antenna elements where there is prior knowledge of the antenna elements in the array. [0028] FIG. 7 is a flowchart illustrating the steps the antenna optimize and control system performs to dynamically tune antenna elements with frequency tuning and impedance matching. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS [0029] The invention now will be described more fully hereinafter with reference to the accompanying drawings, in which illustrative embodiments of the invention are shown. This invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art. [0030] As used herein, the term “and/or” includes any and all combinations of one or more of the associated listed items. Further, the singular forms of nouns and the articles “a”, “an” and “the” are intended to include the plural forms as well, unless expressly stated otherwise. It will be further understood that the terms: includes, comprises, including and/or comprising, when used in this specification, specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof Further, it will be understood that when an element, including component or subsystem, is referred to and/or shown as being connected or coupled to another element, it can be directly connected or coupled to the other element or intervening elements may be present. [0031] FIG. 1 shows a capture system 100 that enables individual users to receive terrestrial television content transmissions captured by antenna elements 102 and streamed to the users. The system 100 allows each user to separately access the feed from a separate antenna element for recording or live streaming of content transmissions. [0032] In a typical implementation, users access the system 100 via packet network(s), which can be private and/or public, such as the Internet 127 , with client devices 128 , 130 , 132 , 134 . In one example, the client device is a personal computer 134 that accesses the system 100 via a browser. In other examples, the system 100 is accessed by mobile devices such as a tablet or slate computing device, e.g., iPad mobile computing device, or a mobile phone, e.g., iPhone mobile computing device or mobile computing devices running the Android operating system by Google, Inc. Other examples of client devices are televisions that have network interfaces and browsing capabilities. Additionally, many modern game consoles and some televisions also have the ability to run third-party software and provide web browsing capabilities that can be employed to access the video from the system 100 over a network connection. [0033] The broadcast content is often displayed using HTML-5 or with a media player executing on the client devices such as QuickTime by Apple Corporation, Windows Media Player by Microsoft Corporation, iTunes by Apple Corporation, or Winamp Media Player by Nullsoft Inc., to list a few examples that are currently common. [0034] An application web server (or application server) 124 manages requests or commands from the client devices 128 , 130 , 132 , 134 . The application server 124 enables the users on the client devices 128 , 130 , 132 , 134 to select whether they want to access previously recorded content transmission, set up recordings of future content transmissions, or watch live broadcast television programs in real time. In some examples, the system 100 also enables users to access and/or record radio (audio-only) broadcasts. [0035] If the users request to watch previously recorded content transmissions, then the application server 124 sends the request of the user to a streaming server 120 , which retrieves each users' individual copy of the previously recorded content transmission from a broadcast file store (or file store) 126 , if that is where it is resident, and streams the content to the client device 128 , 130 , 132 , 134 from which the request originated. If the users request to set up future recordings of content transmissions such as television programs, the application server 124 communicates with an antenna optimization and control system 116 to configure broadcast capture resources to capture and record the desired content transmissions by reserving antenna and encoding resources for the time and date of the future recording. If the users request to watch live broadcast television programs in real time, the antenna optimization and control system 116 identifies antenna resources available for immediate assignment. [0036] In current embodiments, streaming content is temporarily stored or buffered in the streaming server 120 and/or the broadcast file store 126 prior to playback and streaming to the users whether for live streaming or future recording. This buffering allows users to pause, rewind, and replay parts of the television program. [0037] In one implementation, the antenna optimization and control system 116 maintains the assignment of an antenna element 102 to the user throughout any scheduled television program or continuous usage until such time as the user releases the antenna element by closing the session or by the expiration of a predetermined time period as maintained by a timer implemented in the antenna optimization and control system 116 . An alternative implementation would have each antenna element 102 assigned to a particular user for the user's sole usage. [0038] The broadcast capture portion of the system 100 includes an array 103 of the antenna elements 102 - 1 , 102 - 2 . . . 102 - n. Each of these antenna elements 102 - 1 , 102 - 2 . . . 102 - n is a separate antenna element that is capable of capturing different terrestrial television content broadcasts and, through a digitization and encoding pipeline, separately process those broadcasts for storage and/or live streaming to the client devices 128 , 130 , 132 , 134 . This configuration allows the simultaneous recording of over the air broadcasts from different broadcasting entities for each of the users. In the illustrated example, only one array of antenna elements 103 is shown. In a typical implementation, however, multiple two dimensional arrays are used, and in some examples, the arrays are organized into groups of three dimensional arrays. An example of a three dimensional array (which includes arrays 103 - 1 to 103 - n ) is shown in FIG. 2 . [0039] The antenna optimization and control system 116 determines which antenna elements 102 - 1 to 102 - n within the antenna array 103 are available and optimized to receive the particular over the air broadcast content transmissions requested by the users. In a preferred embodiment, the antenna optimization and control system 116 implements an assignment algorithm that optimally assigns users requests to antenna elements 102 - 1 to 102 - n to minimize the amount of coupling between the antenna elements 102 - 1 to 102 - n. [0040] In one implementation, determination of optimized antennas is accomplished by comparing received signal strength indicator (RSSI) values of different antenna elements. RSSI is a measurement of the power of a received or incoming radio frequency signal. Thus, the higher the RSSI value, the stronger the received signal. [0041] In an alternative embodiment, the antenna optimization and control system 116 determines the best available antenna using Modulation Error Ratio (MER). Modulation Error Ratio is used to measure the performance of digital transmitters (or receivers) that are using digital modulation. In short, the antenna element that has the best MER for the desired channel is selected and assigned to receive that channel. [0042] In the illustrated embodiment, the assignment algorithm avoids assigning user requests to antenna elements if the assigned antenna elements will be blocked by other antenna elements tuned to the same or similar channel. Additionally, if the assigned antenna elements must be tuned to the same or similar channel as other adjacent antenna elements, then the antenna optimization and control system 116 assigns user requests to antenna elements that traditionally have had lower coupling when assigned near other antenna elements tuned to the same or similar channel. [0043] In scenarios where coupling cannot be avoided, the antenna optimization and control system 116 dynamically tunes the antenna elements 102 - 1 to 102 - n based on measured parameters. In a typical implementation, the antenna optimization and control system 116 adjust a control voltage sent to varactor diode pairs to dynamically tune the antenna elements 102 - 1 to 102 - n based on measured parameters of the antenna elements. [0044] In still other alternative embodiments, other methods to minimize destructive coupling effects, which minimize least mean squared error of the metric being optimized, could also be implemented. [0045] After identifying antenna elements with adequately minimized coupling, the antenna optimization and control system 116 assigns the user requests to the antenna elements 102 - 1 to 102 - n. The antenna optimization and control system 116 then signals corresponding RF tuners 104 - 1 to 104 - n to tune the assigned antenna elements to receive the requested broadcasts. [0046] The received broadcasts from each of the antenna elements 102 - 1 to 102 - n and their associated tuners 104 - 1 to 104 - n are transmitted to an encoding system 105 as content transmissions. The encoding system 105 is comprised of encoding components that create parallel processing pipelines for each allocated antenna 102 - 1 to 102 - n and tuner 104 - 1 to 104 - n pair. [0047] The encoding system 105 demodulates and decodes the separate content transmissions from the antennas 102 - 1 to 102 - n and tuners 104 - 1 to 104 - n into MPEG-2 format using an array of ATSC (Advanced Television Systems Committee) decoders 106 - 1 to 106 - n assigned to each of the processing pipelines. The content transmissions are decoded to MPEG-2 content transmission data because it is currently a standard format for the coding of moving pictures and associated audio information. [0048] The content transmission data from the ATSC decoders 106 - 1 to 106 - n are sent to a multiplexer 108 . The content transmissions are then transmitted across an antenna transport interconnect to a demultiplexer switch 110 . In a preferred embodiment, the antenna transport interconnect is an nx10 GbE optical data transport layer. [0049] The content transmission data of each of the antenna processing pipelines are then transcoded into a format that is more efficient for storage and streaming. In the current implementation, the transcode to the MPEG-4 (also known as H.264) format is effected by an array of transcoders 112 - 1 to 112 - n. Typically, multiple transcoding threads run on a single signal processing core, SOC (system on a chip), FPGA or ASIC type device. [0050] The content transmission data are transcoded to MPEG-4 format to reduce the bitrates and the sizes of the data footprints. As a consequence, the conversion of the content transmission data to MPEG-4 encoding will reduce the picture quality or resolution of the content, but this reduction is generally not enough to be noticeable for the average user on a typical reduced resolution video display device. The reduced size of the content transmissions will make the content transmissions easier to store, transfer, and stream to the user devices. Similarly, audio is transcoded to AAC in the current embodiment, which is known to be highly efficient. [0051] In one embodiment, the transcoded content transmission data are sent to a packetizers and indexers 114 - 1 , 114 - 2 . . . 114 - n of the pipelines, which packetize the data. In the current embodiment, the packet protocol is UDP (user datagram protocol), which is a stateless, streaming protocol. [0052] Also, in this process, time index information is added to the content transmissions. The content data are then transferred to the broadcast file store 126 for storage to the file system, which is used to store and/or buffer the content transmissions as content data for the various content transmission, e.g., television programs, being captured by the users. [0053] In typical embodiments, the content data are streamed to the users with HTTP Live Streaming or HTTP Dynamic Streaming. These are streaming protocols that are dependent upon the client device. HTTP Live Streaming is a HTTP-based media streaming communications protocol implemented by Apple Inc. as part of its QuickTime X and iPhone software systems. The stream is divided into a sequence of HTTP-based file downloads. HDS over TCP/IP is another option. This is an adaptive streaming communications protocol by Adobe System Inc. HDS dynamically switches between streams of different quality based on the network bandwidth and the computing device's resources. Generally, the content data are streamed using Hypertext Transfer Protocol (HTTP) or Hypertext Transfer Protocol Secure (or HTTPS). HTTPS combines HTTP with the security of Transport Layer Security/Secure Sockets Layer (or TLS/SSL). TLS/SSL are security protocols that provide encryption of data transferred over the Internet. [0054] FIG. 2 is a schematic perspective view of an exemplary card cage 151 , which is shown in phantom. The card cage 151 functions as an enclosure to house antenna array cards 152 - 1 to 152 - n to create a three-dimensional array of antenna elements. The three dimensional array is comprised of multiple two dimensional antenna arrays 103 - 1 to 103 - n. [0055] The sides 150 - 1 , 150 - 2 , top 150 - 3 , bottom 150 - 4 , front portions 150 - 5 , and rear 150 - 6 walls of the card cage 151 are fabricated from a conductive material to maximize Faraday shielding of the antenna elements from the active electronics. The front wall 150 - 5 of the card cage provides an open port as the boresight 201 of the antenna arrays 103 - 1 to 103 - n and faces a television transmitter 204 of the broadcasting entity. Some examples of broadcasting entities include The American Broadcasting Company (ABC), The National Broadcasting Company (NBC), CBS broadcasting corporation (CBS), and The Public Broadcasting Service (PBS). The rear wall 150 - 6 of the card cage 151 includes data transport interfaces 211 that connect the antenna array cards 152 - 1 to 152 - n to the remainder of the encoding system 250 , which includes the transcoders 112 - 1 to 112 - n, packetizers and indexers 114 - 1 to 114 - n, and broadcast file store 126 (shown in FIG. 1 ). The transcoders 112 - 1 to 112 - n, packetizers and indexers 114 - 1 to 114 - n, and file store 126 are preferably located in a secure location such as a ground-level but or the basement of a building, which provides protection from weather and elements and generally has better control over the ambient environment. [0056] In a current embodiment, each antenna array 103 - 1 to 103 - n includes 80 antenna elements that are located outside the Faraday shielding of the card cage 151 . Typically, the antenna elements are dual loop antennas. Thus, in the current embodiment with 80 antenna elements, there are 160 loop antennas. In alternative embodiments, as many as 320 antenna elements (640 loops antennas) or possibly 640 antenna elements (1280 loops antennas) are installed on each antenna array card 152 - 1 to 152 - n. Each antenna is approximately 0.5 inches in height, 0.5 inches wide, or about 1 centimeter (cm) by 1 cm, and has a thickness of approximately 0.030 inches, or about a 1 millimeter (mm). In terms of the antenna elements, when configured as a square loop, the 3 sided length is preferably less than 1.7 inches (4.3 cm), for a total length of all 4 sides being 2.3 inches, (5.8 cm). [0057] Air dams 210 - 1 to 210 - n divide the antenna arrays 103 - 1 to 103 - n from the tuner demodulator sections 111 - 1 to 111 -n. The air dams 210 - 1 to 210 - n act to block the airflow for the antenna array cards 152 - 1 to 152 - n and fill in the gap between the cards such that the air dam of each card engages the backside of its adjacent card. Additionally, the air dams 210 - 1 to 210 - n also act as part of the Faraday shields to reduce electromagnetic interference (EMI). [0058] Typically, the antenna array cards 152 - 1 to 152 - n are orientated vertically, with the antenna elements horizontal to create a horizontally polarized (Electric Field) half omni-directional antenna array. Additionally, the antenna elements protrude out of the front of card cage 208 to further help reduce interference between the components (e.g., tuner and demodulators) and the antenna arrays 103 - 1 to 103 - n. [0059] Alternatively, if over the air content from the broadcasters has a vertical polarization, which occurs in some locales, then orientation of the antenna array cards 152 - 1 to 152 - n and antennas should be changed accordingly. The illustrated example shows the orientation of the antennas for broadcasters with horizontal polarization. [0060] FIG. 3A is a circuit diagram of a multi-band antenna 102 - 1 and tuning feed network 200 for an antenna system 100 , which has been constructed according to the principles of the present invention. [0061] In the illustrated circuit diagram, a multi-band antenna element 102 - 1 is shown as a dual band antenna. In the illustrated example, the antenna element 102 - 1 further includes a low frequency antenna element 102 A- 1 and a high frequency antenna element 102 B- 1 . In alternative embodiments, however, additional antenna elements could be implemented to form a tri-band antenna or a multi-band antenna with three or more antenna elements. In still other embodiments, the antenna is constructed from only a signal antenna element that covers both bands of interest or only a signal band. [0062] In a typical implementation, the low and high frequency antenna elements 102 A- 1 , 102 B- 1 are electrically small loop antennas. Loop antennas have an inductance that is proportional to the area carved out by the loops. Here, the antenna elements 102 A- 1 , 102 B- 1 are rectangular. Other shapes such as circular shaped loop antennas known in the art could also be implemented. Electrically small antennas are defined for a particular wavelength lambda (X) and radius “a” of the sphere enclosing an antenna. Then, if 4πa<λ(4*pi*a is less than lambda), the antenna is considered electrically small. See Wheeler, “Fundamental limitations of Small Antennas, Proceedings of the IRE, Vol. 35, December 1947, pp. 1479-1484. [0063] Generally, the antenna element 102 - 1 is multiply resonant. This enables the antenna element 102 - 1 to have optimal performance at a wide range of frequencies and reject interference from other signals that may be in the same band as the desired signal. [0064] In general, smaller antennas are preferable to achieve higher density, yet smaller antennas typically have a lower gain. As a result in other embodiments larger antennas/antenna elements are used, such as antennas/antenna elements with a total length of up to 20 cm, or even up to 50 cm or 100 cm, and possibly even larger understanding that there is a concomitant decrease in packing density. [0065] A resonance of the antenna element 102 - 1 , and each of the other antenna elements 102 - 2 to 102 - n, is controlled via a respective tuning feed network 200 . The tuning feed network 200 includes a radio frequency (RF) coupling and direct current (DC) injection section 203 , a high frequency tuning section 205 , and a low frequency tuning section 207 . In a typical implementation, the components of the tuning feed network 200 are mounted on the antenna array card (e.g., 152 - 1 to 152 - n in FIG. 2 ) adjacent to the antenna element 102 - 1 . [0066] In the illustrated example, the low frequency tuning section 207 and low frequency antenna element 102 A- 1 are designed to receive carrier signals in the VHF (Very High Frequency) range or 174 MHz to 216 MHz. The high frequency tuning section 205 and high frequency antenna element 102 B- 1 are designed to receive carrier signals in the UHF (Ultra High Frequency) range or 470 MHz to 700 MHz. [0067] In a typical implementation, antenna elements (e.g., reference numerals 102 - 1 to 102 - n in FIG. 1 ) are grouped together on an antenna array card (reference numerals 152 - 1 to 152 - n in FIG. 2 ) to form an antenna array (reference numerals 103 - 1 to 103 - n in FIG. 2 ) of antennas. Each antenna element 102 - 1 to 102 - n within the antenna array 103 is tuned by a separate tuning feed network 200 . Implementing a separate tuning feed network 200 for each antenna 102 - 1 to 102 - n enables each antenna to be individually tuned to a different frequency. [0068] Returning to FIG. 3A , a RF connection from the low frequency tuning section 207 to low frequency antenna element 102 A- 1 is made via capacitors C 1 and C 3 . Capacitors C 1 and C 3 have a capacitance of 2.2 nanoFarads, in one example, and these capacitors form a DC block (low frequency tuning section DC block 214 ). A DC block is a frequency filter designed to filter out lower frequency signals and DC signals while allowing higher frequency RF signals to pass. Additionally, the low frequency tuning section DC block 214 prevents the low frequency antenna element 102 A- 1 from shorting out a tuning voltage sent from the RF coupling and DC injection section 203 . [0069] In alternative embodiments, the RF connection is made with band pass filters, high pass filters, diplexers and/or multiplexers. [0070] Capacitors C 1 and C 3 connect to low frequency tap points 220 a, 220 b of the low frequency antenna element 102 A- 1 . The low frequency tap points 220 a, 220 b are designed to present the desired impedance from the low frequency antenna element 102 A- 1 to the feed lines FEED_P, FEED_N. The location of the intersection of the low frequency tap points 220 a, 220 b with the low frequency antenna element 102 A- 1 and the area cut out between the tap structure contribute to the impedance transformation. [0071] Capacitors C 2 and C 212 are in parallel with the varactor diode pairs D 1 and D 2 . In the illustrated example, capacitor C 2 has a capacitance of 15 picoFarads and capacitor C 212 has a capacitance of 18 picoFarads. The varactor diodes pairs D 1 , D 2 resonate with the inductance of the low frequency antenna element 102 A- 1 to set the tuning frequency. The bandwidth is determined by the value of resistor R 4 along the parasitic resistances in the wire of the low frequency antenna element 102 A- 1 and the varactor diode pairs D 1 and D 2 . Resistors R 1 , R 2 , and R 3 provide high impedance connections for DC tuning voltages that are supplied on the feed line FEED_P to the varactor diode pairs D 1 and D 2 . The high impedance serves two purposes. First, the high impedance provides isolation to the feed lines FEED_P, FEED_N so that RF signal is not lost. Second, the high impedance provides isolation from the varactor diode pairs D 1 and D 2 so they are not disrupted by other impedance/capacitive effects. [0072] Referring to the high frequency tuning section 205 , while there are some differences in the components used and their values, the basic functionality of the circuit is the same as the low frequency tuning section 207 . For example, the high frequency antenna element 102 B- 1 is generally identical to the low frequency antenna element 102 A- 1 in a current embodiment. Additionally, capacitors C 4 and C 7 provide an RF connection from the high frequency antenna element 102 B- 1 to the high frequency tuning section 205 . Likewise, capacitors C 4 and C 7 form a DC block (high frequency tuning section DC block 216 ). Capacitors C 4 and C 7 each have a capacitance value of 24 picoFarads (compared to 2 . 2 nanoFarads for C 1 and C 3 ). Resistor R 7 and R 5 provide a high impedance connection for the tuning voltages provided on feed line FEED_P to varactor diode pair D 3 . The parasitic resistances in the wire of the high frequency antenna element 102 B- 1 and the varactor diode pair D 3 set the bandwidth. Lastly, high frequency tap points 222 a, 222 b are designed to present the desired impedance from the high frequency antenna element 102 B- 1 to the feed lines FEED_P, FEED_N. [0073] The feed lines (FEED N and FEED_P) connect the high frequency tuning section 205 and the low frequency tuning section 207 to the RF coupling and DC injection section 203 . The feed lines (FEED_N, FEED_P) carry the received RF signal from the antenna elements 102 A- 1 , 102 B- 1 , to the RF coupling and DC injection section 203 . In a typical implementation, the physical distance from the RF coupling and DC injection section 203 and the antenna elements 102 A- 1 , 102 B- 1 can be relatively large. For example, in one embodiment the physical distance is twenty or more inches (approximately 0.5 meters). In alternative embodiments, however, the physical distance is only a few inches (e.g., approximately 5 to 8 centimeters). [0074] The tuning feed network further includes an impedance matching circuit 136 , which matches the impedance between the RF coupling and DC injection section 203 and the high and low frequency tuning sections (reference numerals 205 , 207 , respectively). Impedance matching circuits help maximize power transfer and provide an additional means to dynamically tune the antenna element. In the illustrated example, an impedance control line (ICNTL) 137 provides a control signal to adjust the impedance matching circuit. In the illustrated example, the impedance matching circuit 136 is located in the antenna section 111 near the antenna elements. [0075] The RF coupling and DC injection section 203 includes an analog control line (ACNTL) connection 206 and two logical interfaces: DIFF_N 202 coupled with DIFF_P 204 . The two logical interfaces DIFF_N 202 , DIFF_P 204 are differential radio frequency connections that carry received carrier signals to a receiver (or tuner) and demodulator (reference numerals 104 - 1 and 106 - 1 in FIG. 1 ) that are located on an antenna array card (reference numeral 152 in FIG. 2 ). The ACNTL connection 206 is a single-ended analog control line that is referenced to ground (e.g., GND- 1 ) and provides the control signal, to tune the varactor diode pairs D 1 , D 2 , D 3 . In the current embodiment, the control signal is a tuning voltage. In the illustrated embodiment, the control signal from the ACNTL connection 206 is generated by the antenna optimization and control system 116 . The control signal from the antenna optimization and control system 116 is converted to a voltage by a digital to analog converter 170 . A common tuning voltage is provided to the low and high frequency tuning sections 205 , 207 and the antenna elements 102 A- 1 , 102 B- 1 . [0076] In an alternative embodiment, the control signal could be a differential control signal. In this embodiment, another input control signal is injected at GND- 2 and connected at the end of resistor R 6 (GND- 2 would be removed/replaced). [0077] Capacitors C 5 and C 8 are blocking capacitors and form a DC block (RF coupling and DC injection DC block 208 ). The RF coupling and DC injection DC block 208 provides the ability to superimpose the control signal from ACNTL connection 206 on the same feed line (FEED_P) as the received carrier signals from the low and high frequency antenna elements 102 A- 1 , 102 B- 1 . [0078] Typically, when creating a multi-band antenna, two or more antenna elements are put in parallel. There are several important factors to account for when combining multiple antenna elements. For example, in band (where the antenna is tuned), the impedance as measured at the low frequency tap points 220 A, 220 B will look like a single pole bandpass (complex pole-pair) filter having a desired impedance at the resonant frequency. Below the tuned frequency, the impedance will look like a short circuit. Above the tuned frequency, the impedance will approach an open circuit. When implementing the low frequency tuning section DC block 214 , the low frequency tuning section 207 approaches an open circuit at higher frequencies. [0079] Because the low frequency antenna element 102 A- 1 looks like an open circuit when the tuning feed network 200 is operating at higher frequencies, the low frequency tuning section 207 is typically able to connect to the high frequency tuning section 205 without issue. However, the high frequency antenna element 102 B- 1 looks like a short circuit when the tuning feed network 200 is operating at lower frequencies. To protect the low frequency antenna element 102 A- 1 when operating at lower frequencies, high frequency tuning section DC block 216 is used to electrically open the high frequency antenna element 102 B- 1 . [0080] In alternative embodiments, different capacitors values used for the high frequency tuning section DC block 216 . In the illustrated example, the 24 picoFarad capacitor is selected. Similar design considerations are applied when combining additional antennas elements to create tri-band or multi-band antenna elements with, for example, three or more loop antennas. [0081] FIG. 3B is an alternative embodiment of the tuning feed network 200 for the antenna system 100 . [0082] The illustrated example is nearly identical to the circuit diagram of FIG. 3A . In the illustrated example, however, the impedance matching circuit 136 is located between the DIFF_N 202 and DIFF_P 204 inputs and the RF coupling and DC injection DC block 208 (e.g., capacitors C 5 and C 8 ). Additionally, the impedance matching circuit 136 is located in the tuner and demodulator section 109 . [0083] FIG. 4 is a flowchart illustrating the steps the antenna optimize and control system 116 performs to dynamically tune an antenna element. In the illustrated example, the antenna optimize and control system 116 has no prior information about the antenna elements within the array. [0084] In the first step 304 , the antenna optimize and control system 116 determines if a new channel is requested by a user. If a new channel is not requested by the user, then the antenna optimize and control system 116 waits until a new channel is requested. [0085] If a new channel is requested by the user, then the antenna optimize and control system 116 selects an optimized antenna element and applies default settings of the selected antenna element for the requested channel in step 306 . In the next step 308 , the antenna optimize and control system 116 measures parameters of the antenna elements. In a preferred embodiment, the measured parameters include received power of the antenna element, signal quality of the antenna element, temperature of the antenna element, impedance of the antenna element, and/or automatic gain control level, to list a few examples. [0086] In the next step 310 , the antenna optimize and control system 116 calculates a divergence for each measured parameter. The divergence is calculated to provide a vector derivative based on coupling of all antenna elements. In a typical implementation, the divergence is calculated via a conjugate gradient, mapping techniques, or using ad hoc optimization algorithms. Alternative implementations may implement other methods to calculate the divergence, which are known in the art. [0087] Next, in step 312 , the antenna optimize and control system 116 applies limits for the parameters. This is done so that antenna elements that do not need to be adjusted are ignored. In a typical implementation, the users are selectively assigned antenna elements throughout the array to minimize coupling between adjacent antenna elements. Thus, in some scenarios, the antenna elements will not need to be adjusted (even though they could be adjusted) because the antenna elements are able to adequately receive the requested channel using the default tuning parameters. That is, the additional tuning of the antenna element would only provide a minimal (or negligible) increase in the quality of the received signal. [0088] In the next step 314 , the antenna optimize and control system 116 applies parameter weights to prioritize the measured parameters. Each parameter measured in the tuning process is multiplied by a pre-defined constant (weight). An increased weight will increase the impact a parameter has on the tuning algorithm. A smaller weight will cause a parameter to have less impact on the tuning algorithm. A weight of zero will eliminate the impact of a parameter. Thus, parameters with higher weights have higher impact and higher priority. [0089] In the next step 316 , the antenna optimize and control system 116 adjusts the tuning of the selected antenna element based on the modified parameters. [0090] In the next step 318 , the antenna optimize and control system 116 determines if a new channel is requested by a user. If a new channel is not requested by the user, then the antenna optimize and control system 116 returns to step 308 to measure parameters of the antenna elements. If a new channel is requested by the user, then the antenna optimize and control system 116 returns to step 306 to apply default settings of the newly requested channel. [0091] FIG. 5 is a flowchart illustrating the steps the antenna optimize and control system 116 performs to dynamically tune antenna elements 102 - 1 to 102 - n. In this embodiment, there is no prior information about the measured parameters of the antenna elements 102 - 1 to 102 - n. [0092] In general, because there is no prior knowledge about the measured parameters, information about all the antennas must be measured before elements can be adjusted. This is because any adjustment to one antenna element can affect other antenna elements within the array. By measuring all the parameters of all the antenna elements first, the antenna elements are tuned with respect to the other antennas. [0093] In the illustrated example, steps 402 - 410 are identical to steps 302 - 310 of FIG. 4 . [0094] In the next step 412 , the antenna optimize and control system 116 ignores null effect controls from other antenna elements (i.e., not the selected antenna element). In a preferred embodiment, the null effect controls are antenna elements, which are not close in physical distance or tuned frequency to cause interference (e.g., coupling) with the selected antenna. In a typical implementation, the antenna optimize and control system 116 includes predefined frequency and distance thresholds. If the other antenna elements exceed the thresholds, then the antenna optimize and control system 116 ignores the measured parameters from these antenna elements. In a preferred embodiment, the frequency threshold is one channel higher or lower than the channel of the selected antenna element. In a preferred embodiment, the distance threshold is the physical distance between antennas such that the coupling while on the same channel is less than or equal to −20 decibels. [0095] Lastly, in the illustrated example, steps 414 to 420 are identical to steps 312 - 318 of FIG. 4 . [0096] FIG. 6 is a flowchart illustrating the steps the antenna optimize and control system 116 performs to dynamically tune antenna elements. In this embodiment, there is prior knowledge of the parameters of the antenna elements. [0097] Steps 502 - 506 are nearly identical to steps 302 - 310 of FIG. 4 . In the illustrated example, multiple threads (i.e., independent sequences) are created for each new channel requested by individual users (shown as steps 504 - 1 to 504 - n ). [0098] The prior knowledge of the antenna elements enables the antenna optimize and control system 116 to ignore antenna elements above predefined distance and frequency thresholds in steps 508 and 510 , respectively. [0099] In the next step 512 , the antenna optimize and control system 116 measures parameters of the antenna elements. In the next step, 514 , the antenna optimize and control system 116 measures parameters and calculates the divergence for the parameters of the antenna elements. [0100] In the next step 516 , the antenna optimize and control system 116 removes null effect controls to further ignore antenna elements that will not have an effect on the selected antenna. Even though some antenna elements were ignored in steps 508 and 510 , the antenna optimize and control system 116 ignores additional antennas elements in step 516 because new users are being assigned antennas, current users are stopping their service (i.e., discontinuing use of assigned antennas), and current users are also changing channels. [0101] Lastly, in the illustrated example, steps 518 to 524 are identical to steps 312 - 328 of FIG. 3 . [0102] FIG. 7 is a flowchart illustrating the steps the antenna optimize and control system 116 performs to dynamically tune antenna elements with frequency tuning and impedance matching. [0103] Similar to step 504 - 1 to 504 - n in FIG. 6 , multiple threads 604 - 1 to 604 - n are created for each new channel requested by different users. In the first step 604 , the antenna optimize and control system 116 determines if a new channel is requested by a user. [0104] If a new channel is not requested by the user, then the antenna optimize and control system 116 waits until a new channel is requested. If a new channel is requested, then, the antenna optimize and control system 116 applies default settings for the elected antenna element for the requested channel in step 606 . [0105] In the next step 608 , the antenna optimize and control system 116 determines if the last adjacent frequency has been adjusted. If the last adjacent frequency has not been adjusted, then the antenna optimize and control system 116 performs frequency tuning (e.g., FIGS. 4-6 ) for the antenna elements in step 610 . [0106] If the last adjacent frequency has been adjusted, then the antenna optimize and control system 116 performs impedance matching for the antenna elements in step 612 . In a typical implementation, the impedance matching is performed by the impedance matching circuit (e.g., reference numeral 136 in FIGS. 3A-3B ). [0107] In the next step 614 , the antenna optimize and control system 116 determines if a new channel is requested. If a new channel is not requested, then the antenna optimize and control system 116 returns to step 608 . If a new channel is requested, then the antenna optimize and control system 116 applies defaults settings of the selected antenna element for the requested channel in step 606 . [0108] While this invention has been particularly shown and described with references to preferred embodiments thereof, it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the scope of the invention encompassed by the appended claims.

A system and method for dynamically tuning antenna elements is disclosed. The method comprises: receiving requests to capture over the air broadcasts; selecting an antenna element from a group of available antenna elements to capture one of the requested over the air broadcasts; applying default settings to tune the selected antenna element to capture the one of the requested over the air broadcasts; and dynamically tuning the selected antenna element to enhance reception of the one of the requested over the air broadcasts. The method may further comprise measuring parameters toward optimizing the selected antenna element. The method may also include maintaining the tuning of the selected antenna element until the received request is automatically released because time has elapsed. The method may additionally include recording and/or streaming the requested broadcast to an end-user.

BACKGROUND OF THE INVENTION This invention relates generally to a method and apparatus for destroying chemical and biological warfare (CBW) agents present in the air. More specifically, but without limitation, the present invention relates to a method and apparatus for producing a large volume, and thermally-conditioned air supply for a building, vehicle or other inhabited area by using non- contaminating heat to destroy CBW agents that may be present in the ambient, breathable air supply. In the past, various methods have been proposed to remove CBW agents from breathable air supplies such as mechanical filtration and chemical absorption. These systems usually consist of high efficiency air filters followed by absorber beds of activated carbon. However, these systems cannot guarantee that 100% of known CBW agents will be removed or that the system will work at all against an unknown CBW agent or against a virus, which is extremely small, and may pass-through unabsorbed and unremoved. In addition, contaminated filters and absorber beds must be removed and carefully disposed of presenting an extreme handling and environmental problem. Other systems using heat have also been proposed since most chemical and biological warfare agents are organic compounds and can readily be oxidized or disassociated at temperatures of 500° F. to 1000° F. Biological agents are also destroyed at these temperatures. Accordingly, high temperature flames and jets have been proposed for both decontaminating the exterior of ships, tanks and other weapon systems and for oxidizing various materials present in the air. U.S. Pat. No. 3,904,351 to Smith et. al. dated Sep. 9, 1975 discloses an apparatus that produces a flame to decompose contaminants and U.S. Pat. No. 3,898,040 to Tabak dated Aug. 5, 1975 discloses an incinerator with burner means to thermally oxidize combustibles. Although these systems may remove CBW agents, they introduce additional undesirables in the form CO 2 , CO and other contaminants. In addition, the heated air must then be cooled to an acceptable level requiring additional equipment and expense. Further, if a cool air supply is desired, air conditioning equipment must also be employed at greater expense and complexity. Thus, there is a need in the art to provide an apparatus and method that can quickly and completely heat large volumes of air to destroy CBW agents, and that can quickly and efficiently cool the heated air to provide a breathable, warm air supply or further cool the air to provide a cool (air conditioned) breathable, air supply. It may also be desirable to provide a breathable air supply at a positive pressure to drive out and keep any contaminant from entering a building, tank or other space. It is therefore an object of the present invention to provide an apparatus and method for quickly and completely heating contaminated air to destroy CBW agents. It is another object of the present invention to provide a method and apparatus wherein the heated air may then be easily and efficiently cooled to any desired temperature. It is a further object of the present invention to provide an apparatus and method for providing a breathable air supply at a positive pressure. SUMMARY OF THE INVENTION Accordingly, the method and apparatus of the preferred embodiment of the present invention includes heating contaminated air in a compressor by adiabatic compression; flowing the compressed hot air through a reaction vessel to provide sufficient contact time to kill CBW agents; initially, partially cooling the hot, compressed air in an aftercooler; and finally cooling the hot, compressed air by expansion in a turbine (mechanical expander). Energy is recovered from the turbine (mechanical expander) and coupled to the compressor to increase efficiency. Additional power is supplied to the compressor by means of an external power source (e.g. gas turbine engine). BRIEF DESCRIPTION OF THE DRAWINGS Other objects, features and advantages of the present invention will become more fully apparent from the following detailed description of the preferred embodiment, the appended claims and the accompanying drawings in which: FIG. 1 is a schematic of the present invention showing the flowpath and relationship of the various elements. FIG. 2 is a graph showing the time for 99% decomposition of 3 CBW agents at various temperatures. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT The preferred embodiment of the present invention is illustrated by way of example in FIG. 1, contaminated air 2 (under standard temperature and pressure) enters compressor 4 and is adiabatically compressed wherein the temperature of air 2 is caused to rise to approximately 850° F. It should be noted that this temperature (850° F.) was chosen for the preferred embodiment since the CBW agents shown in FIG. 2 are destroyed in approximately 1 second at this temperature range. However, higher or lower temperatures may be chosen when, for example, it is desired to destroy CBW agents other than those depicted in FIG. 2 or when a different contact time is desired. It should also be noted that since the air is adiabatically heated, complete and even heating is obtained, thereby ensuring that no CBW agents escape through the system in "cold spots" as may be found in, for example, conventional combustion or electrically heated systems. In the preferred embodiment, compressor 2 is a thermally insulated compressor capable of compressing air to approximately 350 psi with little loss of heat to the environment. In small flow capacity systems, for example, less than 750 cfm, compressor 2 may be positive displacement design such as a piston cylinder, metal diaphragm or rotary screw type. In larger flow capacity systems, for example, greater than 750 cfm, compressor 2 may be a multistage centrifugal type. Suitable and preferred compressors are manufactured and/or commercially available from Pressure Products Industries, Warminster, Pa.; Burton Corblin N.A. Inc., Horsham, Pa.; or Cooper Industries, Quincy, Ill. Other compressors may be employed by those skilled in the art. Hot, compressed air 2 is then ducted to reactor vessel 6 via pipeline 8. The purpose of reactor vessel 6 is to provide sufficient high temperature contact time for the chemical reactions to occur. (In some embodiments, compressor 4 alone or compressor 4 in combination with pipeline 8 may provide sufficient contact time at the desired temperature without the need for reactor vessel 6. However, in most embodiments reactor vessel 6 will be required.) As shown in FIG. 2, at a temperature of 850° F. a contact time of less than approximately one second is required. It should be noted that FIG. 2 depicts □ as GB (Sarin) nerve agent; Δ HD (mustard) blister agent; ∘ as VX nerve agent. In addition, part of each curve is shown in dashed lines (----) indicating that the dashed line portion is interpolated. Reactor vessel 6 is a conduit, insulated to minimize heat loss to the environment and may be fabricated from 18-8 stainless steel and wrapped with high temperature thermal insulation material such as calcium silicate. In the preferred embodiment reactor vessel 6 is approximately 25 feet in length with an internal X-sectional area of approximately 7 sq. in and is arranged and configured in a geometrically compact shape as, for example, shown in FIG. 1. For a flow rate of 1000 cfm a residence time of approximately one second is obtained. It should be noted that a ventilation air flow rate of 1000 cfm was chosen for the preferred embodiment and provides sufficient breathing air for 200 people at the American Society of Heating Refrigerating and Air-Conditioning Engineers (ASHRAC) recommended ventilation rate of 5 cfm. If desired, supplemental heat (not shown) may be added to air 2 in reactor vessel 6 by means of electric arc or electric resistance heaters. Air 2 is then ducted to aftercooler 10 via pipeline 12. The basic purpose of aftercooler 10 is to reduce the exit temperature of air 2 leaving aftercooler 10. However, the cooling of air 2 in aftercooler 10 has an ultimate effect on the exit temperature of air 2 leaving turbine 14. Thus, by regulating the temperature of breathable air 2 entering turbine 14 the exit temperature and, hence, the final (i.e. air leaving turbine 14) temperature of air 2 may be regulated. In this way, the final temperature may be regulated between, for example, 50° F. and 110° F. depending on whether an "air conditioned" (i.e. cool) building is desired or whether a heated building is desired. (Aftercooler 10 may be excluded from the system when, for example, the temperature of air 2 leaving turbine 14 is unimportant or when turbine 14 and the remainder of the system interact in such a way that the temperature of air 2 leaving turbine 14 is suitable and/or the additional control provided by aftercooler 10 is not needed.) Aftercooler 10 is an air-to-air heat exchanger and, in the preferred embodiment, removes 425,000 BTU/hr with an ambient cooling air temperature of 100° F., an air 2 inlet temperature of 850° F., a minimum air 2 discharge temperature of 600° F. and an air stream 2 flow rate of 1.25 lb/sec. A suitable and preferred aftercooler 10 is manufactured and commercially available from Armstrong Engineering Associates, West Chester, Pa; Brown Fintulse Company, Houston, Tex.; Excoa Division-Fintube Corp., Pryor, Okla. or Baltimore Aircoil Company, Baltimore, Md. Other aftercoolers may be employed by those skilled in the art. Other cooling means, such as, an air-to-water heat exchanger may be employed by those skilled in the art. Air 2 is then ducted from aftercooler 10 to turbine 14 via pipeline 16. As hot, compressed air 2 flows through turbine 14 air 2 expands and does work on turbine 14. In this way, hot, compressed air 2 is brought to a suitable temperature and pressure for use in a building, tank or other space as a breathable air source. It should be noted that air 2 may be discharged from turbine 14 at a pressure above atmospheric say, for example, 15 psig. When discharged into a building, tank or other closed space, the discharged air 2 will tend to flow out of the building or tank thereby preventing any inflow of CBW agents. A suitable and preferred turbine 14 may be designed and manufactured by Ingersoll-Rand, Woodcliff Lake, N.J., Elliot Company, Jeannette, Pa., Solar Turbines Inc., San Diego, Calif. or Coppus Engineering Corp., Worcester, Mass. These and other companies may also modify and/or adapt existing hardware to meet design requirements. Energy imparted to turbine 14 by hot, compressed air 2 may be recovered and transferred to compressor 4 to increase the efficiency of the system. As shown in FIG. 1, turbine 14 is coupled to compressor 4 by drive shaft 18. (Turbine 14 may be excluded from the system when, for example, it is not desired to recover energy from hot, compressed air 2 and/or when aftercooler 10 alone provides sufficient cooling of air 2. It may also be desirable to utilize turbine 14 to extract energy (cooling) from air 2 without returning the extracted energy back to the system by way of, for example, drive shaft 18.) External power to compressor 4 is supplied by motor 20 through driveshaft 22. In the preferred embodiment, motor 20 is a 150 hp diesel engine based on a compressor 4 efficiency of 80% and an overall turbine 14 efficiency of 90%. A gas turbine or other type of engine may be employed. Obviously many modifications and variations of the present invention are possible in light of the above teachings. It is therefore to be understood that within the scope of the appended claims, the invention may be practiced otherwise than as specifically described.

An apparatus and method for destroying chemical and biological warfare (C agents includes heating contaminated air in a compressor, flowing the hot compressed air through a reaction vessel to provide sufficient contact time to kill CBW agents; initially partially cooling the hot compressed air in an aftercooler; finally cooling the hot, compressed air by expansion in a turbine. Energy is recovered from the turbine to inverse efficiency. Additional power is supplied by external means.

FIELD The present disclosure relates to damper assemblies and more particularly to sleeve damper assemblies for damping sympathetic vibrations in motor vehicle engine components. BACKGROUND The statements in this section merely provide background information related to the present disclosure and may or may not constitute prior art. The impact of unwanted, sympathetic vibration or resonances of elements in mechanical systems ranges from inconsequential, through annoying and service life limiting to problematic and catastrophic. Certainly the extent or magnitude of such sympathetic vibration plays a role in locating a particular activity along the foregoing spectrum. Additionally, the type of product, i.e., whether it is a refrigerator, an air compressor, an electric generator, a motor vehicle powertrain, an airplane or a suspension bridge determines whether the vibration is a nuisance, the source of consumer complaints or a safety issue. The most complex consumer products, at least from a mechanical standpoint, are clearly motor vehicles. With thousands of components, frequent new and re-designed mechanical components, an emphasis on weight reduction, lengthy service lives and vehicle service and care ranging from virtually total neglect to careful and complete, sympathetic vibration or resonance of components is a constant and constantly addressed engineering issue. In motor vehicles, the drive or powertrain tends to be the situs of most sympathetic vibration problems and thus the focus of the most attention. A common area of difficulty typically involves a linear component, such as a cable or tubing, that extends unsupported between two points. The most difficult problems arise when a linear element includes an unsupported length that is free standing, such as a transmission oil fill tube or engine oil dipstick tube. Various solutions have been heretofore proposed. Perhaps the most common involves strengthening the linear element. Such a solution adds to the weight and cost of the component and it still may be subject to sympathetic vibration or resonance—just at a different frequency. Adding additional braces or points of attachment is also a common solution but, once again, it not only adds weight and cost but also increases the time and cost of assembly. The present invention is directed to reducing or eliminating sympathetic vibration of linear components in mechanical systems such as vehicle powertrains. SUMMARY The present invention provides a damper assembly for a linear element of a motor vehicle such as a cable, tube, transmission oil fill tube or engine oil dipstick tube. A first embodiment of the damper assembly constitutes a loose fitting sleeve or annulus disposed about a linear component such as a cable, a cooler pipe or line, a transmission oil fill tube or engine dipstick tube. The sleeve damper assembly may be positioned on a substantially vertical tube by a stop which may be any device such as a sleeve of material having an outside diameter larger than the inside diameter of the damper that is clamped or secured to the tube. In a second embodiment, the damper sleeve is of sufficient length that one end may be clamped to the tube while the other end, which loosely fits on the tube, acts as a damper. The damper sleeve may be fabricated of a material such as closed cell foam or other relatively lightweight, resilient and compressible material. The damper moves or “rattles” in random, chaotic manner to absorb energy and interfere with and thus minimize or eliminate resonance or harmonic vibration of the associated linear element. Thus it is an aspect of the present invention to provide a damper assembly for a linear mechanical element such as a cable, a cooler pipe or line, a transmission fill tube or an engine dipstick tube. It is a further aspect of the present invention to provide a damper sleeve which fits loosely about a linear mechanical element. It is a still further aspect of the present invention to provide a damper sleeve having at least a portion which fits loosely about a linear mechanical element. It is a still further aspect of the present invention to provide a damper assembly which moves or “rattles” in a random, chaotic manner. It is a still further aspect of the present invention to provide a damper assembly which absorbs energy and interferes with and thus minimizes or eliminates unwanted harmonic vibration of an associated mechanical element. Further aspects, advantages and areas of applicability will become apparent from the description provided herein. It should be understood that the description and specific examples are intended for purposes of illustration only and are not intended to limit the scope of the present disclosure. DRAWINGS The drawings described herein are for illustration purposes only and are not intended to limit the scope of the present disclosure in any way. FIG. 1 is a perspective view of a transmission fill tube having a first embodiment of a sleeve damper assembly according to the present invention installed thereon; FIG. 2 is an enlarged, fragmentary, perspective view of a first embodiment of a sleeve damper assembly according to the present invention on a transmission fill tube; FIG. 3 is a perspective view of a transmission fill tube having a second embodiment of a sleeve damper assembly according to the present invention installed thereon; and FIG. 4 is an enlarged, fragmentary, perspective view of a second embodiment of a sleeve damper assembly according to the present invention on a transmission fill tube. DETAILED DESCRIPTION The following description is merely exemplary in nature and is not intended to limit the present disclosure, application, or uses. With reference to FIG. 1 , a transmission fill tube upon which a sleeve damper assembly according to the present invention is mounted is illustrated and generally designated by the reference number 10 . The transmission fill tube 10 is typically an elongate, hollow tube that is secured to and extends upwardly from a transmission housing 12 . The transmission housing 12 receives, locates and protects various components (not illustrated) of the transmission 14 . The transmission fill tube 10 is typically between one foot and four feet in length (30.5 cm. to 122 cm.) in a typical passenger car, light truck or sport utility vehicle and extends from the transmission housing 12 upwardly to a location of convenient access within the engine compartment to a terminus 16 . Depending upon the length of the transmission fill tube 10 , it may include one or more brackets or straps 18 which are secured or attached to the transmission housing 12 and/or an engine 20 by, for example, suitable fasteners such as bolts or machine screws 22 . The transmission fill tube 12 facilitates addition of transmission fluid (not illustrated) to the transmission 14 as needed. In addition to facilitating addition of fluid to the transmission 14 , the transmission fill tube 10 receives a removable flexible, typically flat shaft or dipstick 24 that facilitates determining the level of fluid in the transmission 14 . The dipstick 24 preferably includes a top seal, cap or grommet 26 that closes off the terminus 16 of the transmission fill tube 10 . A significant portion of the transmission fill tube 10 , especially that portion most distant from the transmission housing 12 and adjacent the terminus 16 , may be unsupported. As noted above, such unsupported lengths of a tubular, elongate component such as the transmission fill tube 10 may permit or encourage resonance or sympathetic vibration of the component. Referring now to FIGS. 1 and 2 , a first embodiment of a sleeve damper assembly according to the present invention is illustrated and generally designated by the reference number 30 . The sleeve damper assembly 30 is typically and preferably installed on an unsupported portion of the transmission fill tube 10 . The sleeve damper assembly 30 includes a tubular damper sleeve 32 which defines a through, axial passageway 34 . The damper sleeve 32 is preferably fabricated of conventional closed cell polyurethane foam satisfying ASTM D1056 2D2 and having a UL 94 V-O coating. Other relatively lightweight, softly resilient materials such as foam rubber and materials having different densities are also suitable. The damper sleeve 32 is preferably between about 3 inches (76.2 mm.) to 6 inches (152.4 mm.) in length, preferably has a wall thickness of between about 0.20 inches (5.1 mm.) and 0.35 inches (9.0 mm.) and preferably an inside diameter (the diameter of the axial passageway 34 ) of between 0.75 inches (19.05 mm.) and 1.25 inches (31.75 mm.). Preferably, as well, the outside diameter of the transmission fill tube 10 will be at least one-half of the diameter of the axial passageway 34 . The foregoing dimensions are approximate only and it should be understood that they will vary (even outside the stated ranges) depending upon the density of the material of which the damper sleeve 32 is fabricated, the outside diameter of the transmission fill tube 10 , the particular frequency or band of frequencies desired to be attenuated by the sleeve damper assembly 30 and other design variables. Below the damper sleeve 32 and disposed in supporting relationship with it is a fixed collar, stop or support 36 . The collar, stop or support 36 has an outer diameter that is slightly larger than the diameter of the axial passageway 34 such that the damper sleeve 32 cannot slide along or down the transmission fill tube 10 beyond the location at which the upper edge of the collar, stop or support 36 engages the lower edge of the damper sleeve 32 . The stop or support 36 may be of any suitable material such as the closed cell foam described above or other reasonably durable and lightweight material. If fabricated of closed cell foam or other, similar resilient material, the stop or support 36 may be readily secured to the transmission fill tube 10 by, for example, a strap, cable tie 38 or a similar tensioning device. Alternatively, a suitable adhesive may be utilized. Referring now to FIG. 3 , a second embodiment of a sleeve damper assembly according to the present invention is illustrated and generally designated by the reference number 50 . The second embodiment of the sleeve damper assembly 50 is shown in place on a transmission fill tube 10 ′. The transmission fill tube 10 ′ extends from a transmission housing 12 ′ and may include one or more mounting brackets or straps 18 ′. Typically, the transmission fill tube 10 ′ receives a removable flexible, typically flat shaft or dipstick 24 ′ that facilitates determining the level of fluid in the transmission 14 . The dipstick 24 preferably includes a top seal, cap or grommet 26 ′ that closes off the fill tube 10 ′. Proximate the upper terminus 16 ′ of the transmission fill tube 10 ′, typically in an unsupported region, is disposed the sleeve damper assembly 50 . The sleeve damper assembly 50 includes a single, elongate tubular damper sleeve 52 which defines a through, axial passageway 54 . The damper sleeve 52 is preferably fabricated of conventional closed cell polyurethane foam satisfying ASTM D1056 2D2 and having a UL 94 V-O coating. Other softly resilient materials such as foam rubber and materials having different densities are also suitable. The damper sleeve 52 is preferably between about 4 inches (101.6 mm.) to 7 inches (177.8 mm.) in length, preferably has a wall thickness of between about 0.20 inches (5.1 mm.) and 0.35 inches (9.0 mm.) and preferably an inside diameter (the diameter of the axial passageway 54 ) of between 0.75 inches (19.05 mm.) and 1.25 inches (31.75 mm.). Preferably, as well, the outside diameter of the transmission fill tube 10 ′ will be at least one-half of the diameter of the axial passageway 54 . The foregoing dimensions are approximate only and it should be understood that they will vary (even outside the stated ranges) depending upon the density of the material of which the damper sleeve 52 is fabricated, the outside diameter of the transmission fill tube 10 ′, the particular frequency or band of frequencies desired to be attenuated by the sleeve damper assembly 50 and other design variables. Referring now to FIGS. 3 and 4 , the damper sleeve 52 includes a pair of radially aligned, that is, diametrically opposed, axially extending cuts or slits 56 A and 56 B at the lower end of the damper sleeve 52 , that is, the end most distant from the terminus 16 ′ of the transmission fill tube 10 ′. The damper sleeve 52 is preferably disposed on the transmission fill tube 10 ′ with the cuts or slits 56 A and 56 B aligned horizontally. Threaded through the cuts or slits 56 A and 56 B, around the lower half of the transmission fill tube 10 ′ and over the upper, outside surface of the damper sleeve 52 is a strap or cable tie 58 or similar tensioning or securement device. Positioning the strap or cable tie 58 proximate one end of the damper sleeve 52 (the lower end) allows a maximum length of the damper sleeve 52 to move and vibrate to interfere with and cancel out vibrations and to absorb energy. Fastening the cable tie 58 around the lower half of the transmission fill tube 10 ′ and the upper surface of the damper sleeve 52 maintains an open region 62 within and at the lower portion of the axial passageway 54 to allow dirt and debris to pass through the damper sleeve 52 and thereby prevent the accumulation of dirt and debris within the axial passageway 54 of the damper sleeve 52 which would interfere with its operation. In operation, both the first embodiment of the sleeve damper assembly 30 and the second embodiment of the sleeve damper assembly 50 function in essentially the same way: as untuned, i.e., chaotic, dampers or energy absorbing and dissipating devices to damp unwanted resonances or sympathetic vibrations in unsupported portions of linear elements such as cables, and engine and transmission fill tubes in motor vehicles. Thus, they be readily and easily fitted about and secured to such elements and, without extensive tuning and matching of source and damper fundamental and harmonic frequencies, they function as untuned, chaotic dampers to attenuate the motion of the linear element and to absorb and dissipate vibratory energy over a broad frequency spectrum. The description of the invention is merely exemplary in nature and variations that do not depart from the gist of the invention are intended to be within the scope of the invention. Such variations are not to be regarded as a departure from the spirit and scope of the invention.

A damper for a linear element of a motor vehicle drivetrain such as a cable, a transmission oil fill tube or an engine oil dipstick tube constitutes a loose fitting sleeve or annulus disposed about the linear component. The damper may be positioned on a substantially vertical tube by a stop which may be any device such as a sleeve of material having an outside diameter larger than the inside diameter of the damper that is clamped or secured to the tube. Alternatively, the damper may be of sufficient length that one end may be clamped to the tube while the other end, which loosely fits on the tube, acts as a damper. The damper may be fabricated of a material such as closed cell foam or other relatively lightweight, resilient and compressible material.

BACKGROUND OF THE INVENTION 1. Field of the Invention The invention relates to the field of controlling the application of power to electrical loads, and in particular concerns a controller operable instantaneously to insert a high resistance between a load and a power line, when breaking the circuit between the load and the line. 2. Prior Art Load controllers, such as motor starters and similar circuit breaking contactors, typically comprise a relay that upon energizing of the relay coils, closes an electrical circuit coupling a load to a power source. Often, the controller is equipped with an overload protector which opens the relay to disconnect power from the load upon occurrence of a fault condition. The fault conditions triggering opening of the circuit may be an instantaneous overcurrent or undervoltage on the line, or an average current load that exceeds a predetermined limit. Opening of the contactor relay prevents flow of excessive current that may damage either the line or the load. The timing of the circuit breaking operation is important. In the event of a direct short circuit which sinks a very large current, the relay may be too slow to open in time to prevent damage to the load or line. Furthermore, electrical arcs associated with inductive loads or very excessive currents can weld the relay contacts shut, preventing the safety features of the load controller from opening the relay at all. Even if the relay contacts are able to open, arcing across the relay contacts erodes them. Pitting and accumulation of carbon deposits impede current flow during normal use, and contribute to further arcing in the event of a subsequent protective circuit breaking operation. The present invention applies conductive polymers to the environment of a protective circuit breaking contactor. Certain polymers have a relatively low electrical resistance when the current through the polymer is low, and when the current increases to a high level, such polymers change state very rapidly on the molecular level, and exhibit a very high electrical resistance. The high resistance state may be tens to hundreds of times greater than the nominal, low resistance state at the lower current level. This characteristic can be applied effectively to limit current passing through the polymer. There is a need to protect loads and lines from damaging short-circuit currents, effectively and efficiently, and also to provide basic fault current protection. The combination controller according to the invention achieves this in a load controller having a relay for opening a circuit to a load, with a conductive polymer in series with the relay contacts. The electrical resistance of the conductive polymer increases substantially immediately upon application of a high load current level, thereby inserting protective electrical resistance in series with the load. This combination load controller protects the line and the load from high short-circuit currents, decreases arcing across the relay contacts, and more dependably operates to open the circuit between the line and the load. SUMMARY OF THE INVENTION It is an object of the invention to provide an improved protective contactor that couples and decouples an electrical power line and a load, characterized by minimal series resistance at rated current loading and greatly increased series resistance in the event of excessive current. These and other objects are satisfied according to the invention in a load controller in a compact, easily installed housing with a switchable contactor including an electromagnet and a movable armature for opening and closing contacts in series between a line and a load. A conductive armature bar is movable by the armature to open or close a circuit between an input terminal and an output terminal. The input terminal is coupleable to a power line. The output terminal is coupleable to the load. The input terminal is electrically coupled to one side of a conductive polymer. An opposite side of the conductive polymer is electrically coupled to a conductive bus bar terminating in a first contactor terminal. A second contactor terminal is spaced from the first contactor terminal and is coupled to the output terminal. The armature bar on the movable armature is movable to close the circuit across the first and second contactor terminals, to conduct between the input terminal and the output terminal and thereby to couple power line current to the load. The movable armature can be spring biased into an open position, whereby energizing of the electromagnet overcomes the force of the spring bias to close the current path via the contactor bar. Alternatively, the contactor bar can be spring biased into a closed position wherein the contactor bar is in electrical contact with the first and second contactor terminals, and arranged such that energizing of the electromagnet overcomes the force of the spring bias to open the circuit. The conductive polymer in series with the line and the load is of the type having a relatively low electrical resistance when the flow of current is relatively low, i.e., below a threshold value that is at least slightly higher than a rated current of the line or load. Conductive polymers of this type are known in the art and marketed by the company Raychem under the name Polyswitch™. When current drawn through the polymer increases above the threshold value, the internal temperature of the polymer increases due to resistance heating, causing a large increase in the polymer's electrical resistance and the series resistance of the circuit between the line and the load. The increase in resistance preferably is 1000 to 4000 times the polymer's nominal resistance value at low temperature (low current) conditions. The polymer remains in series with the line and load, but has only a nominal resistance unless heated by overcurrent conditions. The invention includes a logic circuit to control the application of power to the electromagnet coil. The logic circuit preferably is responsive to means for sensing current and/or voltage of the line and load. Sensed current and/or voltage conditions, outside maximum and/or minimum threshold limits, triggers the logic circuit to energize or de-energize the electromagnet coils for opening the circuit between the line and the load, which are respectively coupled to the first and second contactor terminals. Preferably, the logic circuit is arranged such that an over-current or under-voltage condition, etc., must exist longer than a predetermined time period before the logic circuit triggers opening of the contactor. When installed along a line between a power source and a load, the load controller of the invention provides a unique combination of short circuit protection and conventional overload protection. If a load circuit, including for example a motor, develops a short circuit, the circuit may draw a sufficiently large current to damage the motor or the conductors coupling the motor to the power line, due to resistive heating at high current and low series resistance. To avoid expensive damage, typical motor control circuits include a protective relay arranged to open a current path between the power line and the motor when over-current conditions are sensed. Typically, however, the relay does not open for a number of cycles at the power line AC frequency. Even if the protective relay opens relatively promptly, the magnitude of the current drawn by a short circuited motor for even a short time can destroy the motor and/or result in overheating which could damage nearby components or start a fire. However, in the load controller of the invention, a high current passing through the conductive polymer in series with the line and load also immediately causes the polymer to increase greatly in resistance, thereby limiting the short circuit current. The polymer's resistance increases quickly enough to avoid damage to the load and surrounding components. The increase in the resistance of the conductive polymer limits the current flowing to the motor to a value that is below a range in which damage to the load could occur. However, the current flowing to the motor remains higher than a nominal operating current flowing during normal motor operation. A current sensor coupled to the logic circuit senses the level of current supplied to the load and triggers the logic circuit if the current is sensed to be greater than a threshold value higher than the rated current of the line or load. The current logic circuit controls energizing of the electromagnet for opening the relay contacts. After sensing a number of cycles of high, fault current, the logic circuit energizes or de-energizes the electromagnet. Preferably, the logic circuit is arranged to power the electromagnet for drawing the armature toward the electromagnet coils and closing the contacts. Upon release of power, a biasing spring on the armature causes the armature to move away from the electromagnet, which is stationary, thereby moving the conductive armature bar out of position bridging across the first and second contactor terminals, and opening the circuit between the power source and load. The logic circuit can include a voltage sensor for sensing the voltage drop across the conductive polymer. When nominal operating current flows across the polymer, the resistance of the polymer is relatively low and the voltage drop is minimal. A low voltage drop across the polymer thus signals that conditions are normal and that the contactor bar may remain in place to provide an electrical path through the contactor. The voltage sensor can include a threshold detector or similar switching circuit. Excessively high current carried through the conductive polymer, such as in the case of a load short circuit or other catastrophic fault, produces a larger voltage drop across the conductive polymer. Moreover, resistive heating causes the conductive polymer to increase greatly in resistance, leading to a significant increase in the voltage drop across the polymer. A voltage drop above a predetermined threshold signals the logic circuit via the voltage sensor as a fault condition. If the excessive voltage drop persists, e.g., for a number of line cycles, the logic circuit switches off the power to the electromagnet coil, thereby breaking the circuit between the power source and the motor. The resistance of the conductive polymer increases greatly almost immediately upon commencement of an excessive current such as caused by a short circuit. Although the load circuit may be directly shorted, current flow is limited by the conductive polymer, which in that case is coupled in parallel with the line. Due to such current limitation, arcing is less likely to occur when the contactor bar is separated from the contactor terminals. It is known that continued arcing between terminals will eventually interfere with the ability of the terminals to conduct electricity by contributing to pitting and carbon build-up on the terminals. That situation is prevented by the conductive polymer. Only very high currents, such as those that result from a short circuited load, are sufficient to substantially increase the resistance of the conductive polymer, which has a nonlinear relationship of resistance to temperature, and therefore current. Currents that are slightly over nominal do not substantially affect the resistance of the conductive polymer. Upon start-up of a heavy duty electric motor, the motor coils draw approximately six times the current drawn during normal, continuous operation. Preferably, the conductive polymer does not respond to this extent of overcurrent, which is expected in a load circuit of this type. Therefore, the presence of the conductive polymer in series with the line and the motor does not inhibit start-up by triggering the logic circuit to open the circuit. In the event of an overload, the motor or other load circuit may draw excess current, but not of the extreme magnitude of a direct short-circuit. In that event, the combination controller can open the circuit between the power line and the load by sensing the load current in known manner. Fault currents which are usually much less than short-circuit currents, are sensed by a current sensor coupled to the logic circuit, for example with a threshold detector as above. If the fault current persists longer than a given duration, the logic circuit de-energizes the stationary magnet releasing the armature bar to move away from the contactor terminals, and opening the circuit between the power line and the motor or other load. No increase in resistance of the conductive polymer occurs. The load current can be sensed from the voltage drop across the conductive polymer. According to Ohm's Law (V=IR), an increase in current drawn by the motor across the conductive polymer causes an increase in the voltage drop across the polymer, even absent an increase in polymer resistance. The increase in voltage drop across the polymer is sensed by the voltage sensors of the logic circuit, which de-energizes the electromagnet magnet to open the circuit between the power line and the motor. Repairs presumably are then made to remedy the fault condition before recoupling the load to the line. BRIEF DESCRIPTION OF THE DRAWINGS There are shown in the drawings certain exemplary embodiments of the invention as presently preferred. It should be understood that the invention is not limited to the embodiments disclosed as examples, and is capable of variation within the scope of the appended claims. In the drawings, FIG. 1 is sectional view of a combination controller in accordance with the invention. FIG. 2 is a current vs. time graph showing various currents associated with the controller. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A combination electrical load controller 10 according to the invention, for providing short circuit and general overload protection for a motor or other type of load, is shown in FIG. 1. The controller 10 includes a housing 11 for protecting the internal controller components. Housing 11 is generally compact and easily mounted in a circuit between a power line and a load being controlled and/or protected. Housing 11 has flanges 12 provided with fastening apertures 13, and can be fastened to a preferably rigid structure such as the panel of a junction box, by use of fastening devices such as rivets or screws placed through fastening aperture 13. Housing 11 is constructed of plastic or comprises non-conductive material for isolating the conductors and avoiding grounding or shorting of the power line. Controller 10 includes an input terminal 14 coupled to a load driving power source or line. Conductive polymer 15 is electrically coupled to input terminal 14. An opposite side of conductive polymer 15 is electrically coupled to bus bar 16. Bus bar 16 is preferably constructed of heavy gage copper or another suitable, high-current conductor. Bus bar 16 terminates in first contactor terminal 17. A second contactor terminal 18 is laterally spaced from the first contactor terminal 17. Second contactor terminal 18 is electrically coupled to output terminal 19. Output terminal 19 is coupled to a load, such as a motor. A return conductive path from the load is also required; however it is sufficient if only one of the two conductors coupling the line and load has a protective circuit breaking arrangement. Armature bar 20 is conductive and has armature bar terminals 21 and 22 affixed at its opposite ends. Armature bar terminals 21 and 22 are aligned with first contactor terminal 17 and second contactor terminal 18, respectively. Armature bar 20 is fixed to movable armature 23, which is biased by armature spring 24 into an open circuit position where armature bar terminals 21 and 22 are spaced from first contactor terminal 17 and second contactor terminal 18, respectively. Logic circuit 25 controls energizing of coil 26, wound on a stationary magnet or ferromagnetic body 27, forming an electromagnet. For coupling power to a load through the device, logic circuit 25 is controlled, such as by switching means (not shown), to energize coil 26. The magnetic flux induced by energizing coil 26 attracts movable armature 23 downwardly toward stationary magnet or body 27. The force of attraction caused by the induced magnetic field overcomes the opposing biasing force of armature spring 24. When movable armature 23 moves downwardly, armature bar terminals 21 and 22 contact first contactor terminals 17 and second contactor terminal 18, respectively, thereby closing the circuit between input terminal 14 and output terminal 19. Logic circuit 25 includes current sensors 28 and/or voltage sensors 29. Current sensors 28 and voltage sensors 29 are electrically coupled to logic circuit 25, which controls energization/de-energization of coil 26. In the event of excessive current being sensed by the logic circuit via current sensors 28, or via the voltage drop across the variable resistance polymer 15, sensed by voltage sensors 29, the logic circuit is triggered to open the contacts. For example, logic circuit 25 de-energizes coil 26 if a fault overload current above a selectable threshold persists longer than a selectable time period. Similarly logic circuit 25 de-energizes coil 26 to open the circuit between input terminal 14 and output 19 if the line voltage goes out of predetermined limits. The logic circuit can be arranged to respond to excessive short term current level at a high threshold level, and to excessive long term current at a threshold that is somewhat lower. Preferably, the logic circuit also responds to line voltage above or below high and low voltage thresholds as well. In normal operation, logic circuit 25 energizes coil 26, drawing movable armature 23 downward to bridge across first contactor terminals 17 and 18, respectively, thereby closing a current path between input terminal 14 and output terminal 19. Current flows through terminal 14, conductive polymer 15, bus bar 16, armature bar 20 and output terminal 19, to the load, such as a motor. Whereas the normal resistance of the conductive polymer is relatively low, current flow is not substantially impeded even though the conductive polymer is in series with the load and line. Conductor polymer 15 is of the type that changes state rapidly into a state of high resistance when conducting a relatively high current, i.e. one above a selectable threshold level. The dimensions and type of particular conductive polymer is selected based on the rated operating current of the load, i.e., the conductive polymer is large enough that in normal operation the magnitude of current is below a threshold level that would cause the conductive polymer to change to its high resistance state due to heating. FIG. 2 is a graph showing current flow through controller 10. The solid line depicts normal current flow. For example, upon start-up the load (e.g., a motor) draws a higher current than normal until the load stabilizes in steady-state operation. As shown on FIG. 2, the start-up current lasts for a time T. The start-up current drawn by the load through controller 10 includes a portion which is significantly higher than a controller relay open threshold value. However, the start-up current in excess of the controller relay opening threshold lasts for a duration which is shorter than an allotted start-up time built into logic circuit 25, for example via an RC timing arrangement, the timing operation of a processor or similar logic circuit, or the like. For example, the relatively high currents drawn by the load during start-up and sensed by current sensor 28 or voltage sensor 29 last for time T o . Time T o is less than the threshold time of logic circuit 25 which would trigger logic circuit 25 to de-energize coil 26 and open the circuit between input terminal 14 and output terminal 19. When the load stabilizes, the current drawn by the load levels off at a value less than the controller relay open threshold current. The maximum current drawn by the load on start-up, i.e. the peak start-up current is less than a value which would trigger conductive polymer 15 to change into a high resistance state. The controller of the invention provides a unique combination of protection from both short-circuit and overload (fault) currents, and can also respond to undervoltage conditions and the like. Assuming that a short-circuit develops in the load or in conductors leading between the controller and the load the load may draw very excessive current. Such an occurrence is illustrated by the dashed lines in FIG. 2. The short circuit current quickly climbs to a magnitude sufficient to trigger conductive polymer 15 to switch into its high resistance state. Conductive polymer 15 changes to its high resistance state quickly enough to avoid major damage to the load, the conductors and any surrounding components due to the substantial current, for even a relatively short time period. The switch of the conductive polymer 15 to its high resistance state inserts additional series resistance into the line and thereby impedes current flow through controller 10. The short circuit current is substantially limited by the high resistance of conductive polymer 15 to a relatively safe level. Although the change of state of conductive polymer 15 to its high resistance state limits the short-circuit current to an acceptable level, the limited short circuit current remains above the controller relay open threshold current programmed into logic circuit 25. Once the limited short-circuit current persists for a period of time over a specified threshold limit, such as for time t o +t', logic circuit 25 de-energizes coil 26 whereupon biasing armature spring 24 lifts the movable armature 23 upwardly. Armature bar 20, affixed to movable armature 23, likewise moves upwardly, breaking contact between armature bar terminals 21 and 22 and first contactor terminal 17 and second contactor terminal 18, respectively, and removing the conductor otherwise bridging between them. The opening of the current path between input 14 and output terminal 19 cuts power to the load. Tripping of the contactor is preferably indicated visually, e.g. by the position of armature 23. The contactor remains open until reset, and an engineer or technician readily can investigate the source of the short circuit condition in safety, because the load is decoupled from the line. The opening of the current path prevents even limited-short circuit current from flowing through the contactor. Prior to tripping of the contactor, however, the conductive polymer 15 limits the short-circuit current to a lower level by changing into its high resistance state. Continued application of even the limited short-circuit current to the load for an extended length of time could cause damage to the load or to surrounding components. Therefore, the logic circuit opens the circuit when the voltage drop across the conductive polymer or the current as otherwise sensed, remains above a maximum threshold for a predetermined time. The load may draw an excessive amount of current due to overloading or the like, at a level that is less than the magnitude of current which would be drawn in case of a short circuit. Where the load is a motor driving a mechanical load, the mechanical load on the motor could be such that it is over driven and draws excessive current, leading to overheating. An illustration of such a case is shown by the dotted lines of FIG. 2. The overload current drawn by the motor rises above the current relay open threshold, but is much less than a level which would cause switching of conductive polymer 15 into a high resistance state. If the overload current drawn by the motor persists greater than a threshold time period, such as t o +t', the over-load current sensed by current sensor 28 of logic circuit 25 will trigger de-energization of coil 26° De-energization of coil 26 opens the current path between input terminal 14 and output terminal 19. The motor or load will be shut down, whereupon an engineer or technician can investigate the nature of the fault. As noted above, logic circuit 25 can be provided with voltage sensor 29 in conjunction with current sensors 28, or preferably, in lieu of current sensor 28. Voltage sensors 29 sense a voltage drop across conductive polymer 15. A change in the voltage drop across conductive polymer 15 is recognized by logic circuit 25 as an out-of-specification condition in a manner analogous to sensing of over-current by current sensor 28. For example, during normal operation, a voltage is developed across conductive polymer 15 in accordance with the equation V=IR. At start-up, it is known that a start-up current is drawn which can be up to six times higher than the steady state operating current drawn by a load, such as a motor. The high start-up current causes a corresponding relatively high voltage drop across conductive polymer 15. The current drawn during start-up is less than an amount that would cause conductive polymer 15 to switch into a high resistance state, therefore, the value of resistance of the conductive polymer is the same during start-up as it is during normal steady-state operation. The increase in the voltage drop across conductive polymer 15 during start-up lasts for a relatively short duration. The increase in voltage during start-up lasts for less than a threshold time which has been programmed into logic circuit 25. Therefore, logic circuit 25 does not de-energize coil 26 in response to the relatively short duration of relatively high voltage drop across conductive polymer 15, during start-up. At the onset of a short-circuit, conductive polymer 15 switches into a high resistance state to impede the flow of current through controller 10. The increase in resistance results in a substantial increase in the voltage drop across conductive polymer 15, which adds to the voltage drop due to the current level. Provided the increase in voltage drop across conductive polymer 15 persists for an extended period of time, i.e. longer than a predetermined minimum time period programmed into logic circuit 25 or determined by its switching circuitry, logic circuit 25 de-energizes coil 26, opening the circuit between input terminal 14 and output terminal 19. An increase in current due to an overload or fault condition, which current is not of the magnitude of a short-circuit current, causes a corresponding increase in voltage drop across conductive polymer 15 in accordance with the formula V=IR. Once again, if the increased voltage sensed by voltage sensors 29 persists for a sufficiently long duration, logic circuit 25 de-energizes coils 26 causing opening of the circuit between input terminal 14 and output terminal 19. However, such an increase in current is not sufficient to substantially increase the resistance of the conductive polymer. The controller of the invention, therefore, provides a combination of short circuit protection, provided by the conductive polymer and conventional overload protection, provided by a switchable electromagnetic relay, in conjunction with a controlling logic circuit. The invention, having been disclosed in connection with the foregoing variations and examples, additional variations will now be apparent to persons skilled in the art. The invention is not intended to be limited to the variations specifically mentioned, and accordingly reference should be made to the appended claims rather than the foregoing discussion of preferred examples to assess the scope of the invention in which exclusive rights are claimed.

A combination load controller for controlling application of power to a load such as a motor, has an input terminal coupleable to a power source, and an output terminal coupleable to a load. A conductive polymer and a protective, electromagnetic switch are disposed along a current path between the input and output terminals. The conductive polymer has a relatively low electrical resistance during conduction at nominal currents. The resistance of the conductive polymer increases substantially promptly upon conduction of excessive current, e.g., due to a short-circuit. In this manner the load is protected from even short bursts of excessively high, short-circuit current by the insertion of additional series resistance by the conductive polymer. The electromagnetic switch protects the line and load by opening the current path. The switch includes a current or voltage sensor coupled to a logic controller that opens the switch if over-current or under-voltage conditions persist for a predetermined period.

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a technique for reducing cavitation in a system having a low-temperature heat source, and more particularly relates to a system for reducing pump cavitation with which cavitation is reduced very well in a rotary pump used for the supply of a propellant to a rocket engine. 2. Description of the Related Art At the inlet to a rotary pump, there is a decrease in pressure behind the blades rotating at high speed, and in some cases bubbles can form when the pressure drops below the saturated vapor pressure-locally. This is called cavitation. When cavitation does occur, there is a decrease in the pump intake flux or pump outlet pressure, and at the same time the vibration of the pump may increase to the point that the pump breaks. Some of the measures that have been taken in the past for avoiding the occurrence of this cavitation include the following. 1. Raising the pump inlet pressure 2. Reducing the pump speed so as to minimize the pressure drop at the pump inlet 3. Decreasing the outside diameter of the pump inlet In order to increase the payload of a rocket, the overall size and weight of the rocket engine need to be reduced, including reducing the size and weight of the pump system that supplies propellant to the engine. To accomplish this, it is necessary to raise the pump speed so as to increase the attainable pump pressure and also increase the operating pressure of the rocket engine. However, while measures 1 to 3 above do indeed reduce cavitation, they also diminish pump performance so much that the desired high performance cannot be achieved, so the above-mentioned necessity cannot be met. Specifically, with measure 1 , the pressure must be raised in the propellant tank, which requires a corresponding increase in the thickness of the tank walls, and this results in greater tank weight. With measures 2 and 3 , pump performance is diminished, the operating pressure of the rocket engine cannot be raised, and the specific thrust cannot be increased, among other problems. The present invention was conceived in light of this situation, and it is an object thereof to reduce the occurrence of cavitation by means of a simple structure, while maintaining pump performance, in a rotary pump (if the pump has an inducer, this refers to the entire pump including the inducer), and to lower the overall weight and size of a rocket engine by improving the propellant supply system of the engine. SUMMARY OF THE INVENTION The present invention is a pump system in which the temperature of the fluid flowing to the pump is lowered so as to lower the saturated vapor pressure of this fluid, which increases the allowable decrease in fluid pressure and reduces the occurrence of cavitation. The present invention also involves utilizing a low-temperature source present in the pump system, and using this low-temperature source for heat exchange with the fluid flowing to the pump, thereby lowering the temperature of the incoming fluid and reducing the occurrence of cavitation. In the case of a liquid rocket engine, a coolant or another propellant whose temperature is lower than that of the primary propellant can be employed as this low-temperature source. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a concept diagram illustrating the constitution of an embodiment in which the pump system pertaining to the present invention is applied to the propellant supply system of a liquid rocket engine; FIG. 2 is a concept diagram illustrating the constitution of another embodiment in which the pump system pertaining to the present invention is applied to the propellant supply system of a liquid rocket engine; FIG. 3 is a graph of liquid oxygen temperature versus hydrogen/oxygen flux ratio when liquid hydrogen is used to lower the liquid oxygen temperature; FIG. 4 is a graph of the saturated vapor pressure of liquid oxygen when the temperature decrease shown in FIG. 3 is obtained; and FIG. 5 is a graph of the Net Positive Suction Head when the liquid oxygen temperature is decreased as shown in FIG. 3 . DESCRIPTION OF THE PREFERRED EMBODIMENTS An example of application to a liquid rocket engine will be given as an embodiment of the pump system pertaining to the present invention, and will be described below through reference to the drawings. Liquid oxygen and liquid hydrogen, which has an even lower temperature than liquid oxygen, are commonly used as coolants for cooling, or as propellants that serve as fuel, in liquid rocket engines. In this embodiment, liquid hydrogen having a lower temperature than liquid oxygen is utilized as the low-temperature source in this liquid rocket engine to lower the temperature of the liquid oxygen at the liquid oxygen pump inlet, reduce the saturated vapor pressure of the liquid oxygen, and prevent the occurrence of cavitation. FIG. 1 is a concept diagram illustrating the constitution of an embodiment in which the pump system pertaining to the present invention is applied to the propellant supply system of a liquid rocket engine. In this drawing, numeral A is a propellant and numeral B is another propellant that serves as the low-temperature source. With this system, the temperature of the propellant B is lower than the temperature of the propellant A, so the propellant B is utilized as the low-temperature source for cooling the propellant A. For example, in this case the propellant A is liquid oxygen and the propellant B is liquid hydrogen, as discussed above. Numeral 1 is a pump for the propellant A, numeral 2 is a heat exchanger, and numeral 3 is a tank for storing the propellant A. Numeral 4 is a pump for the propellant B serving as the low-temperature source, and supplies the propellant B from a propellant B tank (not shown). Numeral 5 is a rocket engine combustion chamber, and numeral 6 is a rocket engine nozzle. The propellant B is pumped to the heat exchanger 2 by the pump 4 , after which it is sprayed into the rocket engine combustion chamber 5 . The propellant A contained in the tank 3 undergoes heat exchange with the propellant B serving as the low-temperature source in the heat exchanger immediately before flowing into the pump 1 , and this lowers the fluid temperature. Because the fluid velocity of the propellant A is low at the time of this inflow, there is only slight pressure loss inside the heat exchanger 2 , and the temperature decrease resulting from heat exchange is more than beneficial enough to compensate for the decrease in pressure due to this pressure loss. As a result, as will be described below, cavitation is reduced within the pump 1 . The propellants A and B are then supplied to the rocket engine combustion chamber 5 . FIG. 2 is a concept diagram illustrating the constitution of another embodiment in which the pump system pertaining to the present invention is applied to the propellant supply system of a liquid rocket engine. Only the differences from the above embodiment will be described. In this embodiment, numeral A is a propellant, numeral C is a coolant that serves as a low-temperature source for cooling the engine nozzle, and numeral D is a propellant other than the propellant A. With this system, a fluid with a lower temperature than the propellant A is used as the coolant C, and this is utilized as the low-temperature source to cool the propellant A. For example, when the propellant A is liquid oxygen, the coolant C is liquid hydrogen, which has a lower temperature than liquid oxygen. When the propellant A is liquid hydrogen, the coolant C is slush hydrogen, for example, which has a lower temperature than liquid hydrogen. In the above embodiment, the described structure prevented the occurrence of cavitation in the pump for the propellant A, but it should go without saying that with a rocket engine of the type that burns a plurality of propellants as in this embodiment, cavitation can also be reduced in the pump (not shown) for the other propellant D by lowering the temperature of the propellant D with the coolant C, just with the propellant A. For instance, when the propellant D is liquefied methane, the temperature of the propellant D can be lowered by using liquid hydrogen as the coolant C. FIG. 3 is a graph of liquid oxygen temperature versus hydrogen/oxygen flux ratio when liquid hydrogen is used to lower the liquid oxygen temperature through heat exchange in the embodiment shown in FIG. 1 . The vertical axis is the liquid oxygen temperature (K) after heat exchange, while the horizontal axis is the ratio between the liquid hydrogen flux and the liquid oxygen flux. Here, the liquid oxygen prior to heat exchange has a temperature of 90K and a pressure of 400 kPa, while the liquid hydrogen prior to heat exchange has a temperature of 50K and a pressure of 10 MPa. The temperatures of the two fluids are equal after heat exchange. As a result, in a typical case in which the propellant flux ratio (liquid hydrogen flux/liquid oxygen flux) in a liquid hydrogen-liquid oxygen rocket is 0.16, it can be seen that the liquid oxygen temperature after heat exchange decreases to about 65K. FIG. 4 is a graph of the saturated vapor pressure of liquid oxygen when the temperature decrease shown in FIG. 3 is obtained. The vertical axis is the saturated vapor pressure (kPa) of the liquid oxygen after heat exchange, while the horizontal axis is the ratio between the liquid hydrogen flux and the liquid oxygen flux. As shown in the drawing, the saturated vapor pressure of the liquid oxygen is greatly lowered by heat exchange, making it much less likely that cavitation will occur. In general, the value obtained by subtracting the saturated vapor pressure from the inlet pressure and expressing this pressure as the height of a water column is termed the Net Positive Suction Head (NPSH), expressed by the following equation. NPSH =(pump inlet pressure−saturated vapor pressure)/fluid density at pump inlet/gravitational acceleration This value represents the margin up to the evaporation point of a fluid, and the larger is this value, the greater is the margin before cavitation occurs. FIG. 5 is a graph of the NPSH when the liquid oxygen temperature is decreased as shown in FIG. 3 . The vertical axis is the NPSH (m) of the liquid oxygen after heat exchange, and the horizontal axis is the liquid hydrogen flux/liquid oxygen flux. As shown by this graph, when no heat exchanger is used as in the past, this NPSH is 27 m. In contrast, with the embodiment of the present invention, under conditions in which the propellant flux ratio (hydrogen flux/oxygen flux) is 0.16, the NPSH is 32.2 m, which means that an improvement of about 20% in the suction performance can be anticipated. Meanwhile, if the NPSH is the same 27 m as when no heat exchange is performed, the required pump inlet pressure under conditions in which the propellant flux ratio (hydrogen flux/oxygen flux) is 0.16 decreases to approximately 300 kPa in a state in which the liquid oxygen temperature has been lowered to 65K by heat exchange. Specifically, it can be seen that the pump system pertaining to the present invention lowers the pressure inside the propellant tank by lowering the pump inlet temperature. As a result, the walls of the propellant can be made thinner, which makes the tank more lightweight. Also, as can be seen from the above equation expressing the NPSH, the smaller is the NPSH of a pump in a state in which no heat exchange is performed, that is, the smaller is the difference between the initial pump inlet pressure and the saturated vapor pressure, the greater will be the effect of lowering the saturated vapor pressure at the pump inlet. As discussed above, the occurrence of cavitation is reduced with the present invention, which allows the propellant tank pressure to be decreased, and this means that the propellant tank can have thinner walls and be more lightweight, and this increases the weight that the rocket engine is capable of launching. Also, reducing the occurrence of cavitation makes it possible to raise the pump speed, and leads to reductions in pump size and weight. Furthermore, raising the pump speed increases the attainable pump pressure, allows the rocket engine operating pressure to be higher, and allows the overall size and weight of the engine to be reduced. Also, raising the rocket engine operating pressure increases the pressure level inside the nozzle downstream from the combustion chamber, allowing the combustion gas to expand to a larger outlet surface area, boosting the specific thrust, and even leading to a reduction in fuel consumption.

Cavitation is reduced in a rotary pump while the pump performance is maintained by utilizing a low-temperature fluid source already present in the pump system. The fluid from the low-temperature fluid source receives heat from the fluid flowing to the pump, thereby lowering its temperature and the saturated vapor pressure, which increases the allowable margin for a decrease in fluid pressure and reduces the occurrence of cavitation. The pump system may be used for a liquid rocket engine. The fluid velocity of the fluid directed to the pump is low before releasing heat, so there is only a slight pressure loss at the pump. Accordingly, the temperature is lowered and the occurrence of cavitation is reduced within the pump.

BACKGROUND OF THE INVENTION Cardboard boxes for gift and merchandise wrapping conventionally are made of a sheet of material folded flat for storage and opened up for use. The walls of the box in such arrangements are folded over the base sheet and unfolded 90 degrees to make a three-dimensional structure. Although this is a satisfactory way of producing a box, it lacks versatility in that each unit can produce only one size of box. Therefore, to accommodate articles of different sizes, a substantial number of sizes of box units are required. Commercially this leads to a large inventory of different items. Flexibility may be lost in selecting the exact correct size for the box that is to be assembled. BRIEF SUMMARY OF THE INVENTION The present invention provides a unit that can be made into a small size box with integral receptacle and lid, or one-half of a large box, at the option of the assembler. When packaged and folded two to a package, the purchaser has the choice of making either two small boxes or one large box from the two units. In commerical use, there is an inventory reduction in that half as many sizes are necessary in the box kits to provide the sizes of boxes needed. The unit is produced from cardboard, preferably, and consists of a rectangular sheet with the side and end walls connected and doubled over in a generally conventional manner. However, the central portions of the side walls are adhesively secured to the base sheet and perforated adjacent the adhesive connections. For making a small size box, the side walls are torn at the frangible perforations so that they can provide separate walls for the receptacle portion and the lid of the box. However, for making half of a large size box, the perforations are left intact so that the side walls remain unitary. The central adhesive connections of the side walls to the base sheet are separated by tearing so that then side walls can stand at 90 degrees to the entire base sheet to form portions of the lid or receptacle portion of the box to be constructed. There are scores formed in the central portion of the sheet to facilitate the bending necessary when the small size box is made with its integral receptacle and lid. However, for the large size box, the material is not bent along these score lines. The resulting unit has the obvious advantage of creating two sizes of boxes from a single unit, with the added advantage of being economically produced and very easily manipulated to construct whatever size box is chosen. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a plan view of a sheet of material used in forming the box unit of this invention; FIG. 2 is a perspective view of the sheet with the side and end walls doubled over the base; FIG. 3 is a fragmentary, perspective view illustrating the manner in which the side and end walls fold together; FIG. 4 is a perspective view of the unit in its normal stored and folded condition; FIG. 5 is a perspective view of the unit being prepared for producing a small size box; FIG. 6 is a perspective view with the small size box complete and the lid open; FIG. 7 is a perspective view of the small size box with the lid closed; FIG. 8 is a perspective view of two of the units prepared to produce a large size box; and FIG. 9 is a perspective view of the large size box in the closed condition. DETAILED DESCRIPTION OF THE INVENTION The flat generally rectangular sheet of cardboard seen in FIG. 1 is used in constructing a box in accordance with this invention. The sheet is provided with transverse scores 10 and 11, spaced inwardly equal distances from and parallel to its end edges 12 and 13, respectively. Additional parallel transverse scores 14 and 15 straddle and are equally spaced from the central transverse axis of the sheet, and are spaced apart a distance equal to the distances of the scores 10 and 11 from the end edges 12 and 13. Longitudinal side scores 17 and 18 are inwardly of the side edges 19 and 20 of the sheet, being spaced from these edges the same distance as the scores 10 and 11 are from their adjacent edges. The score 14 extends across the sheets only between the scores 17 and 18, while the score 15 extends the full width of the sheet to the side edges 19 and 20. Narrow notches 21 and 22 are formed in the sheet, extending inwardly from the side edges 19 and 20, in alignment with the score 10 and with their inner ends at the scores 17 and 18, respectively. Similar notches 23 and 24 are aligned with the score 11 adjacent the opposite end of the sheet. The side extremities 26 and 27 of the end edge 12, beyond the score lines 17 and 18, are recessed a short distance. The same holds true for the end parts 28 and 29 of the other end edge 13. The sheet is perforated along a line 31 which is at 45 degrees to the side edge 19, extending between the intersection of the score lines 10 and 17 and the edge 19. The perforation 31 inclines away from the intersection of the lines 10 and 17 and toward the center of the sheet so as to provide a small triangular section bounded by a portion of the edge 19, the perforation 31 and an edge of the notch 21. A similar perforation 32 inclines at a 45 degree angle from the intersection of the score lines 11 and 17 toward the edge 19. Corresponding perforations 33 and 34 are adjacent the opposite side edge of the sheet, inclining from the intersection of the score lines 10 and 18, and 11 and 18, respectively, toward the side edge 20. Perforations 36 and 37 form continuations of the score line 15, extending respectively between score line 17 and the side edge 19 and the score line 18 and the side edge 20. The perforations 36 and 37 are sufficiently close together to enable the material of the sheet to be torn apart along those lines. The other perforations, however, are merely to facilitate bending of the sheet along the lines of the perforations. There are additional perforations 38 and 39 to facilitate bending of the sheet that incline at 45 degree angles from the side edge 19 to the intersection of the score lines 14 and 17, and from the side edge 20 to the intersection of the score lines 14 and 18, respectively. The sheet then is folded to the position of FIG. 2, being bent along the score lines 10, 11, 17 and 18, as well as the perforations 31, 32, 33 and 34. This provides end panels 41 and 42 between the score line 10 and the end edge 12 and the score line 11 and the end edge 13, respectively, which are bent 180 degrees about the score lines 10 and 11 to overlie the main surface of the sheet. They also overlie the side edge panels 43 and 44 which are bent inwardly 180 degrees about the score lines 17 and 18, respectively. The end flaps 46 and 47 of the end panel 41, beyond the score lines 17 and 18, are secured by an adhesive 48 to the triangular parts adjacent the perforations 31 and 33 when the panels 41, 43 and 44 have been bent through 90 degrees about the score lines. Also, the end flaps 50 and 51 of the end panel 42, beyond the score lines 17 and 18, respectively, are secured by additional adhesive 48 to the triangular sections bounded by the perforations 32 and 34 when the panels 42, 43 and 44 have been bent through 90 degrees. The end flaps 46, 47, 50 and 51 are doubled under the end panels 41 and 42, in the manner illustrated in FIG. 3. An additional, but relatively small, quantity of adhesive 48 secures the side edge panels 43 and 44 to the main body of the sheet. This adhesive attaches to the side edge panels at the triangular segments between the score line 17 and the perforations 36 and 38, in one instance, and the score line 18 and the perforations 37 and 39 in the other. Preferably for shipping, storing and marketing, the sheet is bent through 180 degrees about the transverse score line 15 to the position of FIG. 4. Thus, it assumes a minimum dimension laterally and has very little thickness. Normally, the units thus folded will be packaged in pairs. This permits the consumer to construct either two relatively small boxes, or one relatively large box from the package. If a relatively small box is to be made, the unit is opened up to the position of FIG. 2. Then the sheet is torn along the perforations 36 and 37, taking care to leave intact the adhesive connection in the triangular areas adjacent the perforations 36 and 37. The end panel 42 and the severed free portions of the side panels 43 and 44 then are opened up by being rotated 90 degrees relative to the base sheet, as seen in FIG. 5. The unit also is bent 90 degrees about the score line 14, and the end panel 42 and the remaining portions of the side panels 43 and 44 are opened up by being rotated 90 degrees, as seen in FIG. 6. As a result, there is a receptacle formed by the end panel 41, the adjacent sections of the side edge panels 19 and 20, a new end panel 52 between the score lines 14 and 15, and the encompassed area 53 of the sheet. A lid is provided by the area 54 of the base sheet beyond the score line 15, as well as the end panel 42 and the severed parts of the side edge panels 19 and 20. Bends are formed along the perforations 38 and 39 as the box is folded in this manner. The box may be closed simply by pivoting the lid downwardly about the score line 15, as seen in FIG. 7, with the end panel 42 fitted over the end panel 41 and the severed portions of the side edge panels 19 and 20 fitting over the portions of the side edge panels forming the receptacle. Two of the units are employed in making one large box. Again the unit initially is opened up from the position of FIG. 4 to the position of FIG. 2. Then the side panels 43 and 44 in their entireties are opened through an angle of 90 degrees, also rotating the end panels 41 and 42. This is done by tearing the material away from the adhesive 48 holding the triangular sections of the side edge panels 43 and 44 to the bottom sheet. This is readily done when the sheet is of cardboard and a small amount of adhesive 48 is used at these locations. The material is not torn at the perforations 36 and 37. Two units are prepared in this way and fitted together to form one large box by telescoping one unit over the other from the position of FIG. 8 to FIG. 9. Thus, it is a simple task to provide either size of box from the unit prepared and folded to its storage position of FIG. 4. The foregoing detailed description is to be clearly understood as given by way of illustration and example only, the spirit and scope of this invention being limited solely by the appended claims.

This invention provides a unit for forming alternatively a relatively small box or one-half of a relatively large box. It includes a rectangular cardboard sheet with interconnected doubled over side and end edge panels. Localized parts of the side edge panels are secured by adhesives to the sheet. Score linesare provided for bending and perforations allow severing the side edge panels for making a relatively small box with integral lid. The side edge panels are left intact and the adhesive is torn away in forming one-half of a relatively large box.

CROSS-REFERENCE TO RELATED APPLICATIONS STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT BACKGROUND OF THE INVENTION [0001] The present invention relates to an industrial control system used for real-time control of industrial processes, and in particular, to integrated drive management and configuration using instantiated objects. One aspect of the invention allows a drive or other peripheral component of an industrial process to be configured using the logic development tool customarily used to configure or otherwise program an industrial controller of the industrial process. [0002] Industrial controllers are special purpose computers used for controlling industrial processes and manufacturing equipment on a real-time basis. Under the direction of a stored program, the industrial controller examines a set of inputs reflecting the status of the controlled process and changes a set of outputs controlling the industrial process. The inputs and outputs may be binary, which is on or off, or analog, providing a value within a continuous range. Typically analog signals are converted to binary words for processing. Industrial controllers differ from conventional computers in that their hardware configurations vary significantly from application to application reflecting their wide range of uses. This variability is accommodated by constructing the industrial controller on a modular basis having removable input and output (I/O) modules that may accommodate different numbers of input and output points depending on the process being controlled. The need to connect the I/O modules to different pieces of machinery that may be spatially separated has led to the development of a remote I/O rack holding a number of I/O modules at a remote location to communicate with a central processor of the industrial control via an adapter module, which in turn is connected with a high speed network linked to the central processor. The adapter exchanges information between the network and the I/O modules. [0003] Industrial controllers further differ from conventional computers in that they must process a large amount of input and output data on a predictable real-time basis. This requires not only that the response time of the industrial controller be extremely fast, but also that the processing delay between a changing input and the response of a reacting output be consistent so that the controller operates predictably over time. [0004] To satisfy these requirements of speed and consistency, many industrial controllers use a “scan” based architecture in which each input and output are sequentially read and written over repeated scans of regular duration. Newer industrial controllers may use a producer/consumer model which allows I/O modules to produce data when sampled rather than waiting for a controller scan. This produce/consume protocol may also be used in the communication between an adapter module and the I/O modules of a remote I/O rack. The immediate production of data makes the data available to be used in the system as quickly as possible and reduces overhead on the controller to actively scan all inputs, even when no new data is available. During operation of an industrial process, the industrial controller consumes data produced by the I/O modules, which acquires or samples data from various components of the industrial process, in a timed loop. Those various components include motor drives and other peripheral devices adapted to carry out various functions of the industrial process. [0005] Industrial controllers execute a stored program to control the industrial process. In this regard, industrial controllers are programmable devices and, as such, are also referred to as programmable logic controllers (PLCs). A number of programming tools have been used to program PLCs for industrial applications. One such programming tool is RSLogix 5000, commercially available from Rockwell Automation, Milwaukee, Wis. These programming tools not only enable a programmer to configure the PLC, but may also present generic profiles of various components of the industrial process, such as a motor drive. The generic profiles provide the programmer with information regarding the supported component so that information can be considered during programming of the PLC; however, the programmer is unable to configure the component, e.g., motor drive, directly within the context of the PLC programming tool. In this regard, a separate programming tool, specific for configuring the component, such as DriveTools, commercially available from Rockwell Automation, Milwaukee, Wis. is required to be launched, either directly by the programmer or by the PLC programming tool, to enable the operator to configure the component. The separate programming tools result in a disconnect that can make programming of the PLC and the controlled components, e.g. motor drives, difficult. [0006] More particularly, the PLC communicates with a drive through a communications module. For the drive to be fully operational, the drive as well as the communications module must be configured. In this regard, an elaborate communications framework has been established in which configuration data is not passed between the PLC and the drive unless the communications module allows the communication. Even if the initial communications hurdles are overcome and the communications module passes the configuration data to the motor drive, the PLC is unable to verify that the data was, in fact, properly received by the motor drive. The PLC can only verify that the communications module accepted the communication. [0007] As a result of the independence between the PLC and the communications module, the PLC cannot verify that the configuration data, even if received, has been properly mapped to parameters of the motor drive. This can be particularly problematic since the mapping mechanism used to map the configuration data to the motor drive is typically unique for the motor drive. If the mapping to the parameters of the motor drive is incorrect, the configuration data may not be stored correctly or the communications module may not permit the data transfer altogether. As a result, a separate error checking tool must be used to verify configuration of the drive and the communications module. BRIEF SUMMARY OF THE INVENTION [0008] The present inventors have developed a programming tool for integrated controller and motor drive management and configuration that overcomes the drawbacks associated with conventional motor drive programming tools. The inventive programming tool provides an interface between the controller and a motor drive that allows the logic development tool used to program the industrial controller to be used to configure the motor drive and its supported components directly. As such, a programmer can program the motor drive in the context of the programming software used to configure the controller. More particularly, within the context of the programming software for the controller, a programmer can configure the topology for the motor drive and provide configuration data (typically parameters) that can be verified directly from within the controller programming software. Motor drive configuration data is typically provided via parameters but may also consist of other types of data. [0009] It is therefore an object of the present invention to provide an industrial control system having motor drives that are configured using the logic development tool customarily used to configure industrial controllers of the industrial control system. [0010] It is also an object of the invention to provide instantiated motor drive objects that create a data structure holding configuration data for a particular motor drive, guide user entry of configuration data into the data structure using data names specific to the particular motor drive, and manage the transfer of the configuration data from a PLC to the particular motor drive when executed on the PLC. [0011] The foregoing and other aspects of the invention will appear from the following description. In the description, reference is made to the accompanying drawings, which form a part hereof, and in which there is shown by way of illustration a preferred embodiment of the invention. Such embodiment does not necessarily represent the full scope of the invention, however, and reference must be made to the claims herein for interpreting the scope of the invention. BRIEF DESCRIPTION OF THE DRAWINGS [0012] FIG. 1 is a simplified diagram of an industrial process and a programming workstation used to program or configure components of the industrial process; [0013] FIG. 2 is a block diagram showing a framework for configuring an industrial controller and a motor drive of the industrial process with a motor drive offline; [0014] FIG. 3 is a block diagram showing a framework for configuring an industrial controller and a motor drive of the industrial process while a motor drive is online; and [0015] FIG. 4 is a flow chart setting forth the steps of configuring a motor drive according to one aspect of the present invention. DETAILED DESCRIPTION OF THE INVENTION [0016] FIG. 1 depicts a general framework of an industrial control system and a computer used to configure the industrial control system. In this regard, the industrial control system 10 includes an industrial controller or PLC 12 that communicates with various components used to monitor or operate an industrial process. An exemplary industrial control system is described in U.S. Pat. No. 6,662,247, the disclosure of which is incorporated herein. Communication between the controller 12 and the controlled components is preferably across a high-speed, serial network 14 , which may be any one of a number of high-speed serial networks including ControlNet, EtherNet, or the like. Exemplary components include motor drives 16 and I/O modules 18 . [0017] The controller 12 includes a stored software program, shown as block 20 , that is stored in memory of the controller and includes executable code that when executed by the controller 12 causes the controller to control operation of the drives 16 , I/O modules 18 , and other controlled components of the industrial control system 10 , as is well-known in the art. [0018] A workstation 22 may be connected to the controller 12 to program the controller 12 , i.e., write or edit program 20 . In a preferred embodiment, workstation 22 includes a computer loaded with a software application 24 designed to allow a user to program the controller 12 . One exemplary programming language is RSLogix 5000, commercially available from Rockwell Automation, Milwaukee, Wis. The controller programming application or tool 24 , which may consist of multiple applications bundled in a programming suite, presents various user interfaces to guide a programmer in the programming, i.e., establishing control logic, for the industrial controller 12 . Additionally, the workstation 22 includes applications that facilitate programming of motor drive 16 within the context of the controller programming tool, as will be described. [0019] More particularly, the workstation 22 accesses, either from local memory or an external memory location such as a server, an add-on configuration interface program 26 that provides integration between the software application 24 and a motor drive object database 28 . The motor drive object database 28 contains object models of various motor drives that can be instantiated, as desired. For instance, a particular motor drive may be used repeatedly throughout an industrial control process. To configure each instance of this particular motor drive, multiple instantiations of the object model of the motor drive may be generated and separately and individually configured to carry out respective functions within the industrial process. Because the configuration interface program 26 is integrated with the software application 24 and is linked to the motor drive object database 28 , a user can instantiate one or more object models 30 of a motor drive for configuration directly within the software application 24 to create particular instantiated objects 32 . [0020] The instantiated objects 32 contain data, when instantiated by the user, configure operation of the motor drive associated with the instantiated object 32 . Moreover, the instantiated objects 32 contain programs that guide the programmer during configuration of the associated motor drive by presenting a graphical template or form 34 identifying configurable parameters for the motor drive by name or other recognizable identifier. Thus, there is a direct mapping between the configuration data of the object and the motor drive. The configuration data for a particular motor drive may then be stored in the data structure of the associated instantiated object and subsequently written to the corresponding motor drive to configure the motor drive. That is, after a programmer has configured the instantiated object for a particular motor drive, the configuration data is stored in memory 35 of the controller 12 and then communicated to the actual motor drive 16 by the controller to complete the configuration process. The instantiated objects 32 also include programming to manage communication of the configuration data to their associated motor drives and interfacing with a Human-Machine Interface (HMI). [0021] Referring now to FIG. 2 , an implementation of the present invention is shown for configuring offline motor drives 16 within the context of the software application 24 used to program an industrial controller 12 . The software application 24 provides a configuration project window 36 into which user interfaces 38 for one or more motor drives may be displayed. The user interfaces 38 are provided by a drive page view plug-in 40 that provides a launch/navigation point for the controller programming tool and the specific components of an instantiated motor drive object 32 . In the illustrated example, two separate instantiated motor drive objects 32 are shown, with each having an associated drive page 42 that is provided to the software application for viewing as a user interface 38 within the context of the configuration project window 36 . Changes made in the user interfaces 38 are automatically communicated to the instantiated motor drive objects 32 by a drives services plug-in 44 that provides a respective drives profile manager 46 for each instantiated object 32 to provide a mapping between the configuration data input on the user interfaces 38 to actual parameters of the motor drive. [0022] As shown in FIG. 2 , multiple instantiated motor drive objects 32 may be simultaneously active and configured. Moreover, as further shown in the figure, multiple applications can access different instantiated motor drive objects. For example, diagnostic application 48 , such as DriveExecutive, part of the RSLogix suite of products from Rockwell Automation of Milwaukee, Wis. may interface with one instantiated object 50 whereas the other instantiated objects are accessed by the programming tool. [0023] As shown in FIG. 3 , when a motor drive 52 is online, i.e., connected to the controller 12 , multiple applications such as the drives services plug-in 44 , and separate diagnostic applications 48 , 54 may access a single instantiated object 56 associated with motor drive 52 . Also, changes made to the configuration data of instantiated object 56 are automatically visible by the other applications accessing the instantiated object 56 . In this regard, changes made to an instantiated object 56 are synchronized so that all applications viewing that instantiated object 56 see the changes in the configuration data. [0024] Referring now to FIG. 4 , the present invention is also embodied in a method for configuring a motor drive within the context of an industrial controller programming tool 24 . The method 58 , which may be embodied in a computer program stored on a tangible and reproducible medium, is initiated to create a configuration file per process block 60 that is stored in the context of the industrial controller programming tool. After creating the configuration file per process block 60 , the programmer then selects a motor drive model per process block 62 that corresponds to a motor drive to be used in the industrial process. The motor drive model is associated with a motor drive object that can then be instantiated per process block 64 to enable the programmer to configure an instantiated object of the motor drive. The instantiated object 32 guides the programmer though the configuration process by presenting user interface components per process block 66 that allow the programmer to establish values for various parameters of the motor drive per process block 68 . The configuration of the instantiated object 32 is then stored per process block 70 as a corresponding image in the controller that is transferred to the motor drive during finalization of the motor drive configuration at process block 72 . [0025] While configuration of a motor drive has been described, it is understood that other controlled components of an industrial process may be similarly configured. [0026] The present invention has been described in terms of the preferred embodiment, and it is recognized that equivalents, alternatives, and modifications, aside from those expressly stated, are possible and within the scope of the appending claims.

A programming tool provides an interface between an industrial controller and a motor drive that allows the logic development tool used to program the industrial controller to be used to configure the motor drive and its supported components directly. This allows a programmer to configure the topology for the motor drive and provide configuration data that can be verified directly from within the controller programming software rather than requiring separate programming and diagnostic tools.

PRIORITY CLAIM This application claims the benefit of the Korean Patent Application No. 69348/2004, filed on Aug. 31, 2004, which is hereby incorporated by reference. FIELD OF THE INVENTION The present invention relates to a driving circuit of an active matrix type organic light emitting diode device, and more particularly to, a driving circuit and driving method for an active matrix type organic light emitting diode device, which can improve luminance uniformity between panels by compensating for changes in threshold voltage of a polycrystalline silicon thin film transistor existing between organic light emitting diode devices. DESCRIPTION OF THE BACKGROUND ART In recent years, liquid crystal devices (LCDs) are currently most commonly used as a flat panel display (FPD) due to the advantage of light weight and low power consumption. However, the liquid crystal devices are not a self light emitting element but a light receiving element and have technical restrictions in brightness, contrast, viewing angles, large size, etc. Thus, recently, the efforts to develop new flat panel displays for overcoming such disadvantages have been actively pursued. An organic light emitting diode, one of the new flat panel displays, is superior to a liquid crystal display in viewing angles, contrast, etc. because it is a self light emitting type, and can be made lightweight and thin, and is advantageous from a power consumption point of view because it requires no backlight. Additionally, the organic light emitting diode has an advantage that it is strong to an external shock, provides a wide range of temperature because it is capable of direct current low voltage driving, has a fast response speed, and is made entirely in a solid phase. Furthermore, it has a cheap manufacturing cost. In a manufacturing process of the organic light emitting diode device, all that is needed is deposition and encapsulation equipment unlike a liquid crystal device or PDP (plasma display panel), thus the process is very simple. If the organic light emitting diode device is driven in an active matrix type having thin film transistors, which are switching devices for each pixel, it shows the same luminance even if a low current is applied. This enables low power consumption, high definition, and large size. FIG. 1 is a view showing a basic structure of a general active matrix type organic light emitting diode device (AMOLED). In FIG. 1 , the general organic light emitting diode display panel comprises gate lines GL 1 ˜GLm and data lines DL 1 ˜DLn arranged to cross each other on a glass substrate with pixel portions 30 formed respectively in rectangular regions of a matrix pattern defined by the gate lines GL 1 ˜GLm and the data lines DL 1 ˜DLn crossing each other. The pixel portions 30 are driven in units of gate lines GL 1 ˜GLm by a scanning signal applied via the gate lines GL 1 ˜GLm, and generates light corresponding to the intensity of image signals applied via the data lines DL 1 ˜DLn. Therefore, in the organic light emitting diode display panel, a scanning line driving circuit 10 for applying scanning signals to the gate lines GL 1 ˜GLm and a data driving circuit for supplying image signals to the data lines DL 1 ˜DLn are manufactured on a single crystal silicon substrate, and attached on a glass substrate of the organic light emitting diode display panel in the same method as a taper carrier package (TCP). In the image display portion, a plurality of gate lines GL 1 ˜GLm arranged in a transverse direction at regular intervals and a plurality of data lines DL 1 ˜DLn arranged in a column direction at regular intervals cross each other. In the regions defined by the gate lines GL 1 ˜GLm and the data lines DL 1 ˜DLn crossing each other, pixels 100 electrically connected to the gate lines GL 1 ˜GLm and the data lines DL 1 ˜DLn are respectively provided. The pixels 100 are driven in units of gate lines GL 1 ˜GLm by a scanning signal applied via the gate lines GL 1 ˜GLm, and generates light corresponding to the intensity of image signals applied via the data lines DL 1 ˜DLn. FIG. 2 is a circuit diagram showing a unit pixel of a general active matrix type organic light emitting diode device. In FIG. 2 , a gate line GL is formed in a first direction, and a data line DL and a power supply line V DD formed at a given interval in a second direction crossing the first direction, thereby forming one pixel region. A switching thin film transistor TR 2 , an addressing element, is connected to the region where the gate line GL and the data line DL intersect. A storage capacitor (hereinafter, referred to as Cst) is connected to the switching thin film transistor TR 2 and the power supply line V DD . A driving thin film transistor TR 1 , a current source element, is connected to the storage capacitor Cst and the power supply line V DD , and an electroluminescent diode EL is connected to the driving thin film transistor TR 1 . The switching thin film transistor TR 2 includes a source electrode S 1 connected to the gate line GL and supplying a data signal and a drain electrode D 1 connected to a gate electrode G 2 of the driving thin film transistor TR 1 , and which switches the electroluminescent diode EL. The driving thin film transistor TR 1 includes a gate electrode G 2 connected to the drain electrode D 1 of the switching thin film transistor TR 2 , a drain electrode connected to an anode electrode of the electroluminescent diode EL and a source electrode S 2 connected to the power line V DD , and serves as a driving device of the electroluminescence diode. In the storage capacitor Cst, an electrode at one side is commonly connected to the drain electrode D 1 of the switching thin film transistor TR 2 and the gate electrode of the driving thin film transistor TR 1 , and an electrode at the other side is connected to the source electrode S 2 and of the driving thin film transistor and the power line V DD . The electroluminescence diode EL includes an anode electrode connected to the drain electrode D 2 of the driving thin film transistor TR 1 , a cathode electrode connected to the ground line GND and an organic light emitting layer formed between the cathode electrode and the anode electrode. The organic light emitting layer is comprised of a hole carrier layer, a light emitting layer and an electron carrier layer. The thus-constructed general organic light emitting diode device (AMOLED) supplies currents through the thin film transistors. Because conventional amorphous silicon thin film transistors are low in carrier mobility, polysilicon thin film transistors with improved carrier mobility have been employed in recent years. In order to show a minute color change, a good gray scale capability is a must-have function in displays. The aforementioned organic light emitting diode device displays images by controlling the amount of current flowing in the electroluminescence diode. The organic light emitting diode device displays gray scales by differentiating the amount of light emission of the organic light emitting diode device by controlling the amount of current flowing in the thin film transistors for supplying currents to the organic light emitting diode device in an active driving method. However, according to a driving circuit and driving method of an organic electroluminescence display device according to the conventional art, the current of the organic light emitting diode is determined according to a gate voltage V IN of a driving polycrystalline silicon thin film transistor TR 1 . The driving polycrystalline silicon thin film transistor TR 1 operates in a saturation region, thus a flowing current is expressed by the following formula (1): I DS =W/L μp C OX ( V DD −V IN +V TH ) 2   (1) wherein W denotes a channel width of the driving thin film transistor, L denotes a channel length, μp denotes a charge transfer rate, V DD denotes a power supply line, V IN denotes a gate voltage, and V TH denotes a threshold voltage. If the threshold voltage of the driving polycrystalline silicon thin film transistor TR 1 between panels is changed, the current of the driving polycrystalline silicon thin film transistor TR 1 and the current of the organic light emitting diode are also changed, thereby making the luminance between panels non-uniform. SUMMARY OF THE INVENTION A driving circuit and driving method for an active matrix type organic light emitting diode device, which can improve luminance uniformity between panels by compensating for changes in threshold voltage of a polycrystalline silicon thin film transistor existing between organic light emitting diode devices. Additionally, a driving circuit and driving method for an active matrix type organic light emitting diode device, may reduce power consumption by gamma compensation by changing a variable voltage Vref value and compensate for the non-uniformity of the characteristics of RGB organic light emitting diodes by applying a variable voltage Vref for each RGB pixel. A driving circuit for an organic light emitting diode device may comprise a plurality of RGB pixels each including: a gate line arranged in a first direction, a data line arranged in a second direction crossing the gate line, and a power supply line arranged in the second direction, at a given interval from the data line, crossing the gate line; a plurality of switching thin film transistors connected to the region where the gate line and the data line intersect; a storage capacitor coupled to at least one of the switching thin film transistors and the power supply line; a driving thin film transistor connected to the storage capacitor and the power supply line; an organic light emitting diode coupled to the driving thin film transistor; a variable voltage signal connected to one of the plurality of switching thin film transistors; and a SELECT signal connected to at least one of the plurality of switching thin film transistors, wherein the variable voltage signal is independently connected to the each of the RGB pixels. Each of the RGB pixels comprises: a first switching thin film transistor connected to the data line; a storage capacitor connected to the first switching thin film transistor; a driving thin film transistor connected to the storage capacitor and the power supply line; and a second switching thin film transistor connected to the driving thin film transistor. The driving circuit of the organic light emitting diode device may comprise: a third switching thin film transistor connected to the second switching thin film transistor connected between the first switching thin film transistor and the storage capacitor to be coupled to the variable voltage signal; and a fourth switching thin film transistor connected to the storage capacitor and between a gate and a drain of the driving thin film transistor, coupled to the first switching thin film transistor and connected to the SELECT signal. The second switching thin film transistor and the third switching thin film transistor may be coupled to the EM signal. In the driving circuit for the organic light emitting diode device, each of the RGB pixels may comprise: a first switching thin film transistor connected to the data line and coupled to the SELECT signal; a second switching thin film transistor connected between the first switching thin film transistor and the storage capacitor and coupled to the variable voltage signal; and a third switching thin film transistor connected to the storage capacitor and between a gate and a drain of the driving thin film transistor. The gate of the second switching thin film transistor may be coupled to the EM signal. In the driving circuit for the organic light emitting diode device, each of the RGB pixels may comprise: a first switching thin film transistor connected to the data line and coupled to the SELECT signal; a second switching thin film transistor connected between the first switching thin film transistor and the storage capacitor and coupled to the variable voltage signal; and a third switching thin film transistor connected to the storage capacitor and between a gate and a drain of the driving thin film transistor. The gate of the second switching thin film transistor may be coupled to the SELECT signal. There is provided a method of driving an organic light emitting diode device according to the invention, wherein a plurality of RGB pixels are driven by: arranging a gate line in a first direction; arranging a data line in a second direction crossing the gate line; arranging a power supply line in the second direction, at a given interval from the data line, crossing the gate line; connecting a plurality of switching thin film transistors to a region where the gate line and the data line intersect; connecting a storage capacitor to the switching thin film transistors and the power supply line; connecting a driving thin film transistor to the storage capacitor and the power supply line; connecting an organic light emitting diode to the driving thin film transistor; connecting a variable voltage signal to one of the plurality of switching thin film transistors; and connecting a SELECT signal connected to at least one of the plurality of switching thin film transistors, wherein the variable voltage signal is independently connected to the RGB pixels and a variable voltage used for preserving a data voltage stored in the respective storage capacitors of the RGB pixels for one frame to adjust the current value of the respective organic light emitting diodes of the RGB pixels. Other systems, methods, features and advantages of the invention will be, or will become, apparent to one with skill in the art upon examination of the following figures and detailed description. It is intended that all such additional systems, methods, features and advantages be included within this description, be within the scope of the invention, and be protected by the following claims. BRIEF DESCRIPTION OF THE DRAWINGS The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and together with the description serve to explain the principles of the invention. In the drawings: FIG. 1 is a view showing a basic structure of a general active matrix type organic light emitting diode device (AMOLED); FIG. 2 is a circuit diagram showing a unit pixel of a general active matrix type organic light emitting diode device; FIG. 3 is a circuit block diagram showing a unit pixel of an organic light emitting diode device according to a first embodiment of the present invention; FIG. 4 is an exemplary view showing the organic light emitting diode device to which a Vref voltage for each RGB pixel is applied according to the first embodiment of the present invention; FIG. 5 is a circuit block diagram showing a unit pixel of an organic light emitting diode device according to a second embodiment of the present invention, in which Vref is used in order to preserve information stored in Cst for one frame like in the first embodiment of the present invention; FIG. 6 is an exemplary view showing the organic light emitting diode device to which a Vref voltage for each RGB pixel is applied according to the second embodiment of the present invention; FIG. 7 is a circuit block diagram showing a unit pixel of an organic light emitting diode device according to a third embodiment of the present invention, which illustrates a case where there is no need to use an EM signal because a n type p-Si TFT is used as the third switching thin film transistor T 4 in the second embodiment of the present invention; and FIG. 8 is an exemplary view showing the organic light emitting diode device to which a Vref voltage for each RGB pixel is applied according to the third embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 3 is a circuit block diagram showing a unit pixel of an organic light emitting diode device according to a first embodiment of the present invention. FIG. 4 is an exemplary view showing the organic light emitting diode device to which a Vref voltage for each RGB pixel is applied according to the first embodiment of the present invention. In the organic light emitting diode device according to the first embodiment of the invention, a gate line (not shown) is formed in a first direction, and a data line (not shown) and a power supply line V DD formed at a given interval in a second direction cross the first direction, thereby forming a pixel region. A first switching thin film transistor T 2 , an addressing element, is connected within a pixel region. A storage capacitor (hereinafter, referred to as Cst) is connected to the first switching thin film transistor T 2 and the power supply line V DD , via transistor T 4 . A driving thin film transistor T 1 , a current source element, is connected to the storage capacitor Cst and the power supply line V DD , and an organic light emitting diode OLED is connected to the driving thin film transistor T 1 . A second switching thin film transistor T 3 is connected between the first switching thin film transistor T 2 and the storage capacitor Cst; a third switching thin film transistor T 4 is connected between the gate and drain of the driving thin film transistor T 1 , and is connected to the storage capacitor Cst; and a fourth switching thin film transistor T 5 is connected between the driving thin film transistor T 1 and the organic light emitting diode OLED. The gate of the third switching thin film transistor T 4 is connected to the first switching thin film transistor T 2 to be coupled to a SELECT (n) signal. The gate of the second switching thin film transistors T 3 is connected to the gate of the fourth switching thin film transistor T 5 to be coupled to an EM (n) signal. The source of the second switching thin film transistor T 3 is connected to a variable voltage Vref, which is a DC voltage. The thus constructed driving circuit and driving method for an organic light emitting diode device according to the first embodiment of the present invention will be described with reference to FIGS. 3 and 4 . In FIG. 3 , the first and third switching thin film transistors T 2 and T 4 are turned ON at the section C where the SELECT (n) is turned ON. At this time, an A node voltage is initialized to a V DD −|V TH |, and a B node voltage becomes V DATA . The second switching thin film transistor T 3 is turned ON at the section D where the SELECT (n) is turned OFF and the EM (n) is turned ON, whereby the B node voltage becomes a variable voltage Vref, which is a DC voltage. The A node voltage is boostrapped by the change rate (V DATA −Vref) of the B node voltage, and becomes “V DD −|V TH |−V DATA −Vref”. In summary of this result, the current of the driving thin film transistor T 1 may be shown as the following expression (2): I OLED =½ K (| V GS |−|V TH |) 2 =½ K ( V DD −V DD +|V TH |+V DATA −Vref−|V TH |) 2 =½ K ( V DATA −Vref ) 2   (2) Wherein K is u×Cox×W/L Resultantly, the current I OLED becomes a function of V DATA and Vref The I OLED value can be adjusted by adjusting the variable voltage Vref, which is a DC voltage used for preserving a data voltage stored in the storage capacitor Cst for one frame. As shown in FIG. 4 , chromaticity and gamma values can be adjusted by such a circuit construction where the variable voltage Vref supply signals are disposed for each RGB pixel configured by the circuit construction as shown in FIG. 3 . It is easier to compensate for the non-uniformity of the characteristics of the RGB organic light emitting diodes (OLED 1 , OLED 2 , OLED 3 ) by applying a Vref when no current flows through driving transistor T 1 as compared to a conventional structure where V DD is applied and the current flowing through driving transistor T 1 is adjusted. A driving circuit for an organic light emitting diode according to a second embodiment will be described with reference to the accompanying drawings. FIG. 5 is a circuit block diagram showing a unit pixel of an organic light emitting diode device according to a second embodiment of the present invention, in which Vref is used in order to preserve information stored in Cst for one frame like in the first embodiment of the present invention. FIG. 6 is an exemplary view showing the organic light emitting diode device to which a Vref voltage for each RGB pixel is applied according to the second embodiment of the present invention. In the organic light emitting diode device according to the second embodiment of the invention, a gate line (not shown) is formed in a first direction, and a data line (not shown) and a power supply line V DD formed at a given interval in a second direction crossing the first direction, thereby forming one pixel region. A second switching thin film transistor T 3 , an addressing element, is connected within a pixel region. A storage capacitor (hereinafter, referred to as Cst) is connected to the second switching thin film transistor T 3 and the power supply line V DD . A driving thin film transistor T 1 , a current source element, is connected to the storage capacitor Cst and the power supply line V DD , and an organic light emitting diode OLED is connected to the driving thin film transistor T 1 . A third switching thin film transistor T 4 is connected between the second switching thin film transistor T 3 and the storage capacitor Cst, and a first switching thin film transistor T 2 is connected between the gate of the driving thin film transistor T 1 connected to the storage capacitor Cst and the power supply line V DD , thus coupling the gate to a SELECT (n) signal. The third switching thin film transistor T 4 is connected between the second switching thin film transistor T 3 and the storage capacitor Cst, thus coupling the source thereof to a variable voltage Vref, which is a DC voltage. The gate of the second switching thin film transistor T 3 is connected to the SELECT (n) signal like the first switching thin film transistor T 2 . Further, the gate of the third switching thin film transistor T 4 is connected to an EM (n) signal. In FIG. 5 , the first and third switching thin film transistors T 2 and T 3 are turned ON at the section C where the SELECT (n) signal is turned ON. At this time, an A node voltage is initialized to a V DD and a B node voltage becomes V DATA . The second switching thin film transistor T 3 is turned ON at the section D where the SELECT (n) signal is turned OFF and the EM (n) signal is turned ON, whereby the B node voltage becomes a Vref voltage. At this time, the A node voltage is boostrapped by the change rate (V DATA −Vref) of the B node voltage, and becomes “V DD −|V TH |−V DATA −Vref”. In summary of this result, the current of the driving thin film transistor T 1 will be shown as the following expression (2): I OLED =½ K (| V GS |−|V TH |) 2 =½ K ( V DD −V DD +V DATA −Vref−|V TH |) 2 =½ K ( V DATA −Vref −|V TH |) 2   (2) Wherein K is u×Cox×W/L Based on the result of the expression of the current, the current I OLED is proportional to a variable voltage Vref as in the first embodiment, and a uniform luminance between panels can be obtained by adjusting the variable voltage Vref As shown in FIG. 6 , chromaticity and gamma values may be adjusted by such a circuit construction that the respective variable voltage Vref supply signals are connected for each RGB pixel configured by the circuit construction as shown in FIG. 5 . FIG. 7 is a circuit block diagram showing a unit pixel of an organic light emitting diode device according to a third embodiment of the invention, which illustrates a case where there is no need to use an EM signal because a n type p-Si TFT is used as the third switching thin film transistor T 4 in the second embodiment of the invention. FIG. 8 is an exemplary view showing the organic light emitting diode device to which a Vref voltage for each RGB pixel is applied according to the third embodiment of the invention. In the organic light emitting diode device according to the third embodiment of the invention, a gate line (not shown) is formed in a first direction, and a data line (not shown) and a power supply line V DD formed at a given interval in a second direction crossing the first direction, thereby forming one pixel region. A second switching thin film transistor T 3 , an addressing element, is connected within a pixel region. A storage capacitor (hereinafter, referred to as Cst) is connected to the second switching thin film transistor T 3 and the power supply line V DD . A driving thin film transistor T 1 , a current source element, is connected to the storage capacitor Cst and the power supply line V DD , and an organic light emitting diode OLED is connected to the driving thin film transistor T 1 . A third switching thin film transistor T 4 is connected between the second switching thin film transistor T 3 and the storage capacitor Cst, and a first switching thin film transistor T 2 is connected between the gate of the driving thin film transistor T 1 connected to the storage capacitor Cst and the power supply line V DD , thus coupling to a SELECT (n) signal. The third switching thin film transistor T 4 is connected between the second switching thin film transistor T 3 and the storage capacitor Cst, thus coupling to a variable voltage Vreft, which is a DC voltage. The gate of the second switching thin film transistor T 3 and the gate of the third switching thin film transistor T 4 are connected to the SELECT (n) signal like the first switching thin film transistor T 2 . In FIG. 7 , the first and third switching thin film transistors T 2 and T 3 are turned ON at the section C where the SELECT (n) signal becomes a low value. When the SELECT (n) signal is changed from a low value to a high value, the second switching thin film transistor T 3 is turned OFF and the third switching thin film transistor T 4 is turned ON, whereby the B node voltage becomes a Vref voltage. At this time, the A node voltage is boostrapped by the change rate (V DATA −Vref) of the B node voltage, and becomes “V DD −|V TH |−V DATA −Vref”. In summary of this result, the current of the driving thin film transistor T 1 will be shown as the following expression (3): I OLED = 1 / 2 ⁢ K ⁡ (  V GS  -  V TH  ) 2 = 1 / 2 ⁢ K ⁡ ( V DD - V DD + V DATA - Vref -  V TH  ) 2 = 1 / 2 ⁢ K ⁡ ( V DATA - Vref -  V TH  ) 2 ( 3 ) Wherein K is u×Cox×W/L Based on the result of the expression of the current, the current I OLED is proportional to a variable voltage Vref as in the second embodiment, and a uniform luminance between panels can be obtained by adjusting the variable voltage Vref. Besides, chromaticity and gamma values can be adjusted by such a circuit construction that respective variable voltage Vref supply portions are connected for each RGB pixel. It is easier to compensate for the non-uniformity of the characteristics of the RGB organic light emitting diodes (OLED 1 , OLED 2 , OLED 3 ) by applying a Vref when no current flows through driving thin film transistor T 1 as compared to a conventional structure where V DD is applied and the current flowing through driving thin film transistor T 1 is adjusted. While various embodiments of the invention have been described, it will be apparent to those of ordinary skill in the art that many more embodiments and implementations are possible within the scope of the invention. Accordingly, the invention is not to be restricted except in light of the attached claims and their equivalents.

Disclosed are a driving circuit and driving method for an organic light emitting diode (OLED) device. The driving circuit for the OLED device comprises RGB pixels each including: a gate line arranged in a first direction and a data line and a power supply line arranged in a second direction crossing the first direction; a plurality of switching transistors connected to the region where the gate line and the data line intersect; a capacitor connected to the switching transistors and the power supply line; a driving transistor connected to the capacitor and the power supply line; an OLED connected to the driving thin film transistor; a variable voltage signal connected to one of the plurality of switching transistors; and a driving signal connected to at least one of the switching transistors, wherein the variable voltage signal is independently connected to the RGB pixels, and the transistors are thin film transistors.

CROSS-REFERENCES TO RELATED APPLICATIONS [0001] The present application is a Divisional of U.S. application Ser. No. 13/617,437, filed on Dec. 28, 2006, entitled “PREDICTIVE AND PROFILE LEARNING SALESPERSON PERFORMANCE SYSTEM AND METHOD,” of which the entire disclosure is incorporated herein by reference for all purposes. [0002] The present application is also related to the following co-pending and commonly assigned U.S. patent applications: [0000] U.S. patent application Ser. No. ______ (Attorney Docket Number 88325-883766(125820US)) filed concurrent herewith and entitled “PREDICTIVE AND PROFILE LEARNING SALES AUTOMATION ANALYTICS SYSTEM AND METHOD,” and which claims priority to U.S. application Ser. No. 13/617,437, filed on Dec. 28, 2006, entitled “PREDICTIVE AND PROFILE LEARNING SALESPERSON PERFORMANCE SYSTEM AND METHOD;” U.S. patent application Ser. No. ______ (Attorney Docket Number 88325-883767(125830US)) filed concurrent herewith and entitled “PREDICTIVE AND PROFILE LEARNING SALES AUTOMATION ANALYTICS SYSTEM AND METHOD,” and which claims priority to U.S. application Ser. No. 13/617,437, filed on Dec. 28, 2006, entitled “PREDICTIVE AND PROFILE LEARNING SALESPERSON PERFORMANCE SYSTEM AND METHOD;” U.S. patent application Ser. No. ______ (Attorney Docket Number 88325-883769(125840US)) filed concurrent herewith and entitled “PREDICTIVE AND PROFILE LEARNING SALES AUTOMATION ANALYTICS SYSTEM AND METHOD,” and which claims priority to U.S. application Ser. No. 13/617,437, filed on Dec. 28, 2006, entitled “PREDICTIVE AND PROFILE LEARNING SALESPERSON PERFORMANCE SYSTEM AND METHOD;” and U.S. patent application Ser. No. ______ (Attorney Docket Number 88325-883768(125850US)) filed concurrent herewith and entitled “PREDICTIVE AND PROFILE LEARNING SALES AUTOMATION ANALYTICS SYSTEM AND METHOD,” and which claims priority to U.S. application Ser. No. 13/617,437, filed on Dec. 28, 2006, entitled “PREDICTIVE AND PROFILE LEARNING SALESPERSON PERFORMANCE SYSTEM AND METHOD.” BACKGROUND [0003] 1. Field [0004] This application relates generally to sales automation and forecasting systems and, more particularly, to tracking and storing sales data for performance prediction. [0005] 2. Background [0006] Sales automation systems are common in the art. In standard usage, these systems aid a sales representative, a sales manager, or both, to be more efficient at selling a product or service. Sales forecasting analytics are commonly a component of a sales automation systems, and are largely focused towards the sales manager to help forecast and manage the sales process. [0007] A sales automation system is generally a tool that allows sales representatives and managers to organize contact records, as well as manage records associated with sales quotes and invoices. It can also work in the context of a ‘Sales Methodology’ where the sales process is structured around the representative working though a set of stages in an attempt to complete a sale. Sales automation tools typically allow the tracking of such records in terms of time periods associated with fiscal or financial accounting. During these ‘sale periods’ it is important for sales representatives and managers to have analytical reports defining progress towards various goals. [0008] Typically the sales representative recognizes the benefit of using a sales automation system for maintaining their list of contacts, but most other tasks are considered overhead with little benefit. Thus, sales automation systems commonly suffer from a lack of full acceptance by the sales staff, which limits their usefulness to the sales managers as well—if the sales representative doesn't utilize the system then the manager does not have a full picture of the sales process. As the sales representative is responsible for using the system to track individual deal progress through the sales stage, should they fail to log the sales progress the system is left without the valuable data necessary for the sales manager to forecast and manage the sales goals. A system that provides incentive to a sales representative to use features beyond a contact management system is needed. Additionally, in part because of the lack of sales data and in part because of the prior state of the art, many analytics used by the sales manager are quite simple models with manual parameters based upon the sales manager's intuitions about prior performance. [0009] Many algorithms in the general field of data mining provide resources to a knowledgeable individual for extracting relevant information from large amounts of data. There exist data mining applications to aid in this process. In some instances there are data mining approaches incorporated into other systems, such as sales automation systems. These incorporated techniques are usually quite rudimentary compared to the full suite of techniques available in a complete data mining system, yet still require some level of sophistication on the part of the user (in sales automation systems the user would be the sales manager). Some of the more advanced techniques available would be standard statistical approaches for assigning error bars or applying a linear regression analysis. These statistical approaches are often guided by or overridden with ad-hoc scaling factors based upon the sales manager's intuition, such as: “Bob usually over promises his amount sold by about 25%, yet Sue is more conservative and usually under promises by 15%. Therefore I will adjust Bob's sales predictions down by 25%, but increase Sue's predictions by 15%.” [0010] There exist new data mining and machine learning techniques which can go beyond the traditional analyses, above, but they require data to work accurately to overcome the ad-hoc manual scaling factors. To collect this data the sales representative must be motivated to provide the information. Stereotypically, sales people are motivated by two goals: meeting personal monetary targets, and out performing their peers. Methods that target these motivations are needed and will increase the acceptance of a sales automation system by the sales people, and hence provide a richer set of useful data to the sales manager. Most prior systems have failed to adequately provide features found compelling to the sales representative, and have overlooked the connection that the sales manager's job is best done with the full data available from an engaged sales representative. Some prior systems have recognized the benefits of catering to the interests of a sales representative, but have neglected to use the data naturally collected by the sales automation system to reflect back and help provide the necessary feedback to keep the system accurately tuned—commonly the systems relied on a manual configuration of the various parameters. [0011] A better sales automation and forecasting management system is needed to address the above noted shortcomings in the prior art. SUMMARY [0012] One aspect of the inventive subject matter includes a sales automation system and a method for scoring sales representative performance and forecasting future sales representative performance. These scoring and forecasting techniques can apply to a sales representative monitoring his own performance, comparing himself to others within the organization (or even between organizations using methods described in application), contemplating which job duties are falling behind and which are ahead of schedule, and numerous other related activities. Similarly, with the sales representative providing a full set of performance data, the system is in a position to aid a sales manager identify which sales representatives are behind others and why, as well as help with resource planning should requirements, such as quotas or staffing, change. [0013] Further aspects include a central repository of logged sales related data including data representative of the progress made through the various sales stages of the sale cycle. The logged sales data is extracted to support the learning forecasting and prediction functions of the present invention. Numerical and quantitative data records can be retrieved based on user request for data. Still further aspects include an incentive because of the ability to provide a sales representative through a user interface current and predictive analysis of their performance relative to their peers and groups of other sales representatives. Some embodiments also provide a tool that allows the sales representative and manager to perform a predictive analysis of their conversion rate to monitor monetary performance. [0014] For example, all calculations can be done to score the performance of individual people and groups with respect to learned data models of top performing sales people as well as with respect to user-entered ideal models of performance. An example of this would be an ideal revenue growth of a sales person over time. A second example is a relative analysis of the person's ongoing sales ‘pipeline’ with respect to learned and ideal models of good performance. In either case the system can learn the historical sales models for an individual or high performing sales representative using any of a variety of machine learning techniques. In addition, an idealized model can be entered by the sales manager. The resulting comparison can aid in the understanding of how individuals relate to one another and to an idealized individual. This helps sales representatives understand their relative performance, and it helps sales managers understand if there is a general deviation between their idealized model and the actual performance of an individual or group. [0015] Another example can be evaluating an entire sales process sales methodology with respect to the ideal model of the process as well as compared to other good performing processes or methodologies. Note that this analysis can be independent of individuals looking at the process in isolation. It can also be used to identify weak individuals or groups that bring the overall performance of the process or methodology down. One aspect of the embodiments is the ability to use the systems and methods in CRM software applied to sales process analysis and its combination with iterative machine learning methods. [0016] With the historical performance of each sales representative stored by the sales automation system, the system can more accurately update the forecasting portion of the sales analytics. [0017] These and other advantageous features of the various embodiments will be in part apparent and in part pointed out herein below. BRIEF DESCRIPTION OF THE DRAWINGS [0018] For a better understanding of the present invention, reference may be made to the accompanying drawings in which: [0019] FIG. 1 is a top level diagram of the system architecture; [0020] FIG. 2 is an illustration of the data agglomeration of the respective elements of the central repository; [0021] FIG. 3 is an illustration of a data query module according to embodiments of the invention; [0022] FIG. 4 is a machine learning and forecasting functional flow according to embodiments of the invention; [0023] FIG. 5 is a future planning module functional flow according to embodiments of the invention; [0024] FIGS. 6 and 7 are diagrams illustrating the revenue growth MLF examples; [0025] FIG. 7 is an illustration of the Ideal Growth Analysis; [0026] FIG. 8 is an illustration of the Ideal Pipeline or Strategic analysis; [0027] FIG. 9 is an illustration of Query, Analytic Comparison and display method; [0028] FIG. 10 is an illustration of the graphical output of Ideal Revenue Growth Analysis; [0029] FIG. 11 is an illustration of the graphical output of Ideal Pipeline or Strategy Analysis; [0030] FIG. 12 is a diagram of the Data Manipulation Algorithm (DMA); [0031] FIG. 13 is a diagram of the DMF flow; [0032] FIG. 14 is a diagram of the Post-DMF Heuristics algorithm; [0033] FIGS. 15A and 15B are a flowchart illustrating a Pipeline Analysis method according to embodiments of the invention; [0034] FIGS. 16A and 16B are flowcharts illustrating a revenue forecasting method according to embodiments of the invention; [0035] FIGS. 17A and 17B are a flowchart illustrating a method for scoring performance according to embodiments of the invention; [0036] FIG. 18 is a flowchart illustrating a method for allocation of quotas by periods according to embodiments of the invention; and [0037] FIG. 19 is a flowchart illustrating a method for allocation of quotas by territories according to embodiments of the invention. INCORPORATION BY REFERENCE [0038] An addition to the disclosure herein relative to the subject matters A-D reference is to be made to the publications listed below: [0039] (A) Queuing Models/Systems: An Introduction to Stochastic Modeling by Samuel Karlin, Howard M. Taylor Academic Press; 3 edition (February 1998) (hereby incorporated by reference for all purposes) [0041] (B) Machine Learning & Data Mining Pattern Recognition, Third Edition by Sergios Theodoridis, Konstantinos Koutroumbas; Academic Press; 3 edition (Feb. 24, 2006) (hereby incorporated by reference for all purposes) Pattern Classification (2nd Edition) by Richard O. Duda, Peter E. Hart, David G. Stork; Wiley-Interscience; 2nd edition (October 2000) (hereby incorporated by reference for all purposes) Machine Learning by Tom M. Mitchell; McGraw-Hill Science/Engineering/Math; 1 edition (Mar. 1, 1997) (hereby incorporated by reference for all purposes) [0045] (C) Forecasting and Prediction: Forecasting: Methods and Applications by Spyros G. Makridakis, Steven C. Wheelwright, Rob J Hyndman; Wiley; 3 edition (December 1997) (hereby incorporated by reference for all purposes) [0047] (D) Sales/Business: Selling and Sales Management by Robert D. Hirsch, Ralph Jackson; Barron's Educational Series (Sep. 29, 1993) (hereby incorporated by reference for all purposes) DEFINITION OF TERMS [0049] Sales Strategy: A sales methodology where the process of selling is organized around a set of abstract ‘stages’, where at each stage the sales person and/or potential customer perform a set of tasks. [0050] Sales Pipeline: A set of potential sales transactions (deals) for a sales person or group in various stages of completion. [0051] Sales Funnel: A standard visual picture of a sales pipeline. [0052] Sales Period: A specific time period when sales activity is conducted and measured. [0053] Sales Quota: A revenue goal for a particular sales person or group of people for a specific ‘sales period’. [0054] Top Performer: A sales person who meets a set of user/system defined performance metrics for a set of sales periods. [0055] Data Agglomeration: The process of grouping a set of raw data points by a particular attribute along with a particular mathematical operator. DETAILED DESCRIPTION OF INVENTION [0056] In the following detailed description of exemplary embodiments of the invention, reference is made to the accompanying drawings that form a part hereof, and in which is shown by way of illustration specific exemplary embodiments in which the invention may be practiced. These embodiments are described in sufficient detail to enable those skilled in the art to practice the inventive subject matter, and it is to be understood that other embodiments may be utilized and that logical, mechanical, electrical and other changes may be made without departing from the scope of the inventive subject matter. [0057] Some portions of the detailed descriptions which follow are presented in terms of algorithms and symbolic representations of operations on data bits within a computer memory. These algorithmic descriptions and representations are the ways used by those skilled in the data processing arts to most effectively convey the substance of their work to others skilled in the art. An algorithm is here, and generally, conceived to be a self-consistent sequence of steps leading to a desired result. The steps are those requiring physical manipulations of physical quantities. Usually, though not necessarily, these quantities take the form of electrical or magnetic signals capable of being stored, transferred, combined, compared, and otherwise manipulated. It has proven convenient at times, principally for reasons of common usage, to refer to these signals as bits, values, elements, symbols, characters, terms, numbers, or the like. It should be borne in mind, however, that all of these and similar terms are to be associated with the appropriate physical quantities and are merely convenient labels applied to these quantities. Unless specifically stated otherwise as apparent from the following discussions, terms such as “processing” or “computing” or “calculating” or “determining” or “displaying” or the like, refer to the action and processes of a computer system, or similar computing device, that manipulates and transforms data represented as physical (e.g., electronic) quantities within the computer system's registers and memories into other data similarly represented as physical quantities within the computer system memories or registers or other such information storage, transmission or display devices. [0058] In the Figures, the same reference number is used throughout to refer to an identical component that appears in multiple Figures. Signals and connections may be referred to by the same reference number or label, and the actual meaning will be clear from its use in the context of the description. Also, please note that the first digit(s) of the reference number for a given item or part of the invention should correspond to the Fig. number in which the item or part is first identified. [0059] The description of the various embodiments is to be construed as exemplary only and does not describe every possible instance of the inventive subject matter. Numerous alternatives could be implemented, using combinations of current or future technologies, which would still fall within the scope of the claims. The following detailed description is, therefore, not to be taken in a limiting sense, and the scope of the inventive subject matter is defined only by the appended claims. [0060] One embodiment of the present invention comprising a central repository of logged sales related data; a machine learning module and a prediction module teaches a novel system and method for sales performance and forecasting. [0061] For simplicity and illustrative purposes, the principles of the present invention are described by referring mainly to an exemplar embodiment, particularly, with references to the Internet and the World Wide Web (WWW) as the exemplary databases of informational items. However, one of ordinary skill in the art would readily recognize that the same principles are equally applicable to, and can be implemented in, other informational database, and that any such variation would be within such modifications that do not depart from the true spirit and scope of the present invention. Similarly, simplicity of description for the present invention makes use of a data warehouse. However, one of ordinary skill in the art would readily recognize that the same functionality can be gained in the absence of a data warehouse through summarized data, simulated data, data models or the like and not depart from the true spirit and scope of the present invention. [0062] FIG. 1 illustrates a representative architecture 100 according to embodiments of the invention. The details of the various embodiments can be better understood by referring to the figures of the drawings. The data warehouse (DW) 102 is the central repository for the supporting the machine learning and forecasting (MLF) 108 and future planning (FP) 110 modules. While those of ordinary skill in the art could readily identify different sets or subsets of elements, for explanatory purposes in the embodiments of the present invention the following elements are described as part of a data warehouse Data Transforms—data Heuristics {Idealized and Learned}—using an Idealized or Learned set of rules or replicable method or approach for directing attention to data key to prediction and forecasting Data Models {Idealized and Learned}—using data models using idealized or learning information Derived Data Store Data Cache Metrics and Scores—related to sales goods Stored Scenarios—fabricated sales conditions Configuration Settings— [0071] One aspect of the DW 102 of the various embodiments is that nearly all elements may have an associated timestamp. One of ordinary skill in the art can clearly see that the DW 102 can be maintained in a database, in working memory, on disk, or by innumerable other means. Similarly, the DW 102 may contain original data, summarized data, machine learned data, or manually configured data. Referring to FIG. 1 , the DW 102 is shown having the various elements listed above. The Data Agglomeration 104 is shown communicably linked to the DW 102 for retrieving and caching records. The Query Module 106 for initiating user queries and displaying is shown communicably linked to the DW. The machine learning module 108 and future planning module 110 is shown communicably linked to DW 102 and Data agglomeration 104 . The DW 102 includes sales data generated from raw sales data manipulated by the MLF 108 and FP 110 to generate learned data based on historical data, and includes idealized data based on benchmarked models or user input or idealized data formulated from data operated on by heuristic rules/algorithms. A display and user interface 116 may be used to access DW 102 . Data provided through user interface 116 may be transformed using run time heuristics and data transforms 118 . Additionally a user interface 114 may be used to provide input and receive output from FP 110 . [0072] FIG. 2 is an illustration of the operation of data agglomeration module 104 according to embodiments of the invention. The Data Agglomeration Module 104 associated with the DW 102 retrieves snapshots of raw sales records/transactions 112 and transcribes the numerical and quantitative data of the records with an attached timestamp at regular intervals. In addition, the records 112 may be accumulated per sales representative and per that representative's management hierarchy. During this process a number of calculations can be made, including but not limited to, standard ‘sales metrics’ like the percentage of a representative's (or group of representatives') sales quota they have attained as of a given date. A data cache and metric score calculated by the Data Agglomeration can be stored back on the DW 102 . [0073] One task of data agglomeration module 104 is to retrieve sales records (sales transactions) 112 and cache a subset of those records, the quantitative data, with a timestamp. The module also can cache data using data transformations as well as using data models, and heuristics in combination with previous data caches to produce various sales metrics. One of ordinary skill in the art can easily determine that the Data Agglomeration module 104 could be performed in a number of different ways and similarly that the scope of the inventive subject matter would not be diminished by not using this module. Rather the inclusion of this module is an efficiency enhancement to the novel aspects of the current invention. Similarly, the caching and agglomeration can occur in memory, on disk, or in any other method which should be obvious to one of ordinary skill in the art. [0074] FIG. 3 is an illustration of a data query module 106 according to embodiments of the invention. The Query Module 106 , also referred to as a Data Query and Display Module (DQ-DM) associated with the DW 102 allows the user initiation of queries and displays the quantitative data graphically in combination with a user's group and other peer groups. Each metric has a customizable graphical display and custom metrics can be created for display. These graphical metrics can be combined with other graphical and tabular data to create a ‘dashboard’ for sales people. [0075] The basic data flow is driven by a user request for data via display and user interface 116 . A query is generated, and the response data is sent to the query module 106 in combinations with various other elements of the DW 102 . Next, the data and elements move to the run-time engine where transforms, heuristics and data models 118 are applied. The resulting retrieved and calculated data is then provided to display components of display and user interface 116 for viewing by the user. [0076] FIG. 4 is a machine learning and forecasting functional flow according to embodiments of the invention. The machine learning and forecasting (MLF) module 108 associated with the DW 102 is a data mining module used within embodiments of the present invention. It takes input from the various sales data tables 112 , user input heuristics, and user input idealized data models. The output is generally various scores on each metric or combinations of metric as well as learned data models. [0077] The MLF module 108 is comprised of a variety of components. Each component contains a collection of algorithms that can be applied both in parallel and sequentially to produce output within a component. The following components are useful in the preferred embodiment, but one with ordinary skill in the art can easily see that not all of the components are necessary, for example, either or both of the heuristics engines 404 and 408 could be eliminated without altering the intended functionality of the current invention. MLF: [0000] Data Manipulation Algorithms (DMA) 402 (further described in FIG. 12 ) Pre-DMF Heuristics Engine (HE1) 404 (further described in FIG. 14 ) Data Mining and Forecasting Algorithms (DMF) 406 (further described in FIG. 13 ) Post-DMF Heuristics Engine (HE2) 408 (further described in FIG. 14 ) [0082] The process flow illustrated in FIG. 4 is as follows: Sales records 112 and elements of the DW 102 are retrieved and input to the DMA 402 which is a component of MLF 108 . The configuration settings specify what algorithms are applied in combination with DW 102 elements. The output of the DMA 402 is passed to HE1 404 which is also a component of MLF 108 along with retrieved heuristics from the DW. Various heuristics specified by the configuration settings are applied to the input. The output of HE1 404 is passed to DMF 406 where configuration settings govern the algorithms used in what combination with DW 102 elements. The output of the DMF 406 is passed to the HE2 408 . Internals proceed similar to step 2. The output of the HE2 408 is sent to the DW 102 . The output may be some combination metric-scores, derived data store, learned data models and learned heuristics. [0088] FIG. 5 is a future planning module functional flow according to embodiments of the invention. The Future Planning and Analysis module (FPA) 110 illustrated in FIG. 5 allows users to play out future scenarios and use learned and idealized models as well as current and past data to execute these scenarios. The FPA 110 module builds upon previous modules capabilities and includes a scenario analysis engine 502 that adds the ability to store and retrieve ‘scenarios’ and execute these scenarios in isolation in addition to changing base data and model values for a particular scenario. Scenario analysis engine 502 interacts with MLF 108 based on input received from a user interface 114 . The results of the scenario may be displayed 504 via user interface 114 . [0089] Examples 6 and 7 discussed below provide example use cases of the FPA 110 . [0090] FIGS. 6 and 7 are diagrams illustrating the revenue growth MLF examples. The MLF module 108 is used to do the main data analysis of the FPA 110 . The module is supplied with previous inputs from the data warehouse 102 and sales records 112 as well as any ‘stored scenarios’ in the DW. The User interface 116 of the FPA module 110 allows the user to manipulate any data point that has been loaded from the DW 102 as well as change parameters of the various ‘models’ used in the MLF module 108 . The changes entered by the UI are updated into the MLF via the ‘Scenario Analysis Engine’ 502 , a sub-component of the FPA 110 that is shown in FIG. 5 . [0091] In addition to accepting data and model changes from the UI, the ‘Scenario Analysis Engine’ 502 contains a specific script, or algorithm, that specifies what components of the MLF 108 are used and in what sequence to produce a desired output analysis 604 . Various analytical methods 602 , such as time series analysis or smoothing methods may be applied. Output analysis 604 may include an idealized average performance profile or and idealized top-performance profile. [0092] FIGS. 1-9 have illustrated various aspects of the system and system operation. Further details on the operation of the system are provided below in FIGS. 15-19 . As noted above, MLF 108 may use various algorithms during its operation. Further details on these algorithms are provided in FIGS. 12-14 . [0093] FIG. 12 provides further details regarding data manipulation algorithms 402 . The Transforms section 1206 lists several example transforms which may apply in some embodiments. One of ordinary skill in the art can recognize that this set of examples is representative and not exhaustive. Similarly, this step might use any number or combination of these transforms without altering the scope or intent of this patent. [0094] FIG. 13 is a flow chart of the Data Mining and Forecasting Algorithms. Example Algorithms 1306 for FIG. 13 include, but are not limited to the following: Bayesian Classsifier Perceptron Algorithm Expectation Maximization K Nearest Neighbor Radial Basis Function Networks Relaxation Discriminate Classification Divisive Clustering Algorithms Agglomerative Clustering Algorithms Ho-Kashyap Procedures Linear Programming Moving Average Forecasting (Family of Algorithms) Box-Jenkins Forecasting Holt-Winters Seasonality Forecasting Wavelet Forecasting Iterative Optimization Algorithms Evolutionary Optimization Algorithms Theoretical Queuing Models [0112] In FIG. 13 , the list of Algorithms 1304 (1 through N) represents any combination of data mining and forecasting algorithms. The system may use a single algorithm or any number of multiple algorithms in conjunction. These algorithms could include any commonly known data mining algorithms such as clustering, outlier detection, linear regression, or any other technique known to someone with ordinary skill in the art. The section labeled “Ensemble Methods” 1306 lists several techniques used to resolve the combination of the data mining algorithms. One of ordinary skill in the art can recognize that this list is non-exhaustive and that any of the listed approaches alone or in combination could be used to achieve the desired purpose. [0113] In FIG. 14 , the section labeled “Apply Rule” 1404 represents any type of rule that would be available in a rules engine or expert system, as known by one of ordinary skill in the art. Examples include, “Deal takes longer than 30 days AND deal size >$10,000” or “Quota attainment >50%” or “Sales funnel stage <3” or “Sales person progress score >B+” or any other construction that proves useful to aiding the sales process. [0114] FIGS. 15-19 are flowcharts illustrating methods according to various embodiments of the invention. The methods to be performed by the embodiments may constitute computer programs made up of computer-executable instructions. Describing the methods by reference to a flowchart enables one skilled in the art to develop such programs including such instructions to carry out the method on suitable processors (the processor or processors of the computer executing the instructions from computer-readable media such as ROM, RAM, CD-ROM, DVD-ROM, flash memories, hard drives and other media). The methods illustrated in FIGS. 15-19 are inclusive of acts that may be taken by an operating environment executing one or more exemplary embodiments of the invention. [0115] FIGS. 15A and 15B are a flowchart illustrating a Pipeline Analysis method according to embodiments of the invention. Although the example method includes details regarding how the modules interact with each other to provide a specific analysis in particular embodiments, it should be noted that operations in the method may be performed by different modules in various alternative embodiments. [0116] In some embodiments, the method used input data comprising a list of sales periods to analyze and a sales strategy to analyze. The method at begins at block 1502 by extracting stage descriptive information from data warehouse 102 for the input sales strategy. At block 1504 , a goal model for a given sales-strategy, sales-period pair is extracted. At block 1506 , fuzzy logic quality and priority heuristics for the given sales-strategy and period are extracted. [0117] One or more of the actions in blocks 1508 - 1514 may be executed for each sales period. At block 1508 , revenue goals for the given sales period are extracted. At block 1510 , previous learned sales period models for the given sales strategy, if any, are extracted from data warehouse 102 . At block 1512 , the data warehouse 102 is queried for sales transaction data for the given sales period. In some embodiments, the sales transaction data may include ongoing, closed, lost or deferred transactions. At block 1514 , a seasonality model for the given sales period is extracted from the data warehouse. [0118] The actions in blocks 1520 - 1528 may be executed for each sales transaction obtained at block 1512 in order to perform data cleaning, data smoothing and/or heuristic classification. At block 1520 , a smoothing method may be used to fill in missing data. At block 1522 , erroneous or biasing data points may be determined and excluded. At block 1524 , sales strategy stage transition times are calculated for each stage. In some embodiments, the DMA module performs the smoothing, exclusion of erroneous or biasing data points and/or calculation of the sales strategy transition times. [0119] At block 1526 , a quality score is classified according to a quality heuristic. At block 1528 , a priority score is classified according to a priority heuristic. In some embodiments, the quality score and the priority score may be classified by a Pre-HE module. [0120] The actions in blocks 1530 - 1538 may be part of a loop that is executed for each sales period in the input sales period list. Further, block 1530 - 1536 may be part of a loop that is executed for each sales strategy stage. At block 1530 , weighted transition times for all sales transaction are computed. At block 1532 , weighted abandonment times for all sales transactions are computed. At block 1534 , the transition and abandonment times are classified according to the current goal model. At block 1536 , a M/M/s or other Queuing Model is built for the current stage. [0121] At block 1538 , the M/M/s Queuing Models for each stage is assembled into a multi-level queuing network. [0122] At block 1540 , a M/M/s Queuing Network goal is built using the goal model. At block 1542 , Queuing Network ‘Previous Data’ is built from a previous learned model. [0123] Blocks 1544 - 1550 are repeated for each learning algorithm, and for ‘n’ time steps within each learning algorithm. At block 1544 , a random sales transaction is selected. At block 1546 , if the randomly selected sales transaction fits the selected ‘Goal’ model, then the ‘Goal’ model weight is reinforced. At block 1548 , if the randomly selected sales transaction fits the selected ‘Previous Data’ model, then a ‘Previous Data’ model weight is reinforced. At block 1550 , if the randomly selected sales transaction fits the ‘Current Data’ model, the a ‘Current Data’ model weight is reinforced. [0124] At block 1552 , an aggregate model is formed by combining each level of the ‘Goal’, ‘Previous Data’ and ‘Current Data’ models using the learned weights. [0125] Blocks 1554 - 1558 may be executed for each sales transaction. If the aggregate model accurately predicts the outcome of the sales transaction (block 1554 ) and the transaction has a high quality score (block 1556 ), then a positive metric score is assigned for the transaction (block 1558 ). [0126] After the sales transactions have been evaluated, a post-HE module may optionally be executed at block 1560 . [0127] At block 1562 the learned metric scores are stored in data warehouse 102 . At block 1564 , the aggregate module is stored as the ‘Previous Data’ in data warehouse 102 . [0128] See Example 3a below for a description of an example application of the Pipeline Analysis method illustrated in FIGS. 15A and 15B . [0129] FIGS. 16A and 16B are flowcharts illustrating a revenue forecasting method according to embodiments of the invention. In some embodiments, a list of sales periods to analyze and a list of sales people to analyze may be supplied as input for the method. A pseudo code description of the method is as follows: [0000]  Extract ‘Goal Model’ for given Sales-Periods (block 1602)  Extract Fuzzy Logic Quality and Priority Heuristics for given Sales-Period (block 1604)  For Each Sales-Period (blocks 1606 1612)   Extract ‘Revenue Goals’ for given Sales-Period (block 1606)   Extract previous learned Sales-Period models for given Sales-Strategy, if any. (block 1068)   Query Sales Transaction Data for Sales-Period {Ongoing, Closed, Lost, Deferred}   (block 1610)   Extract Seasonality Model for given Sales-Period (block 1612)  For Each Sales Transaction (blocks 1620-1628)   Use smoothing method to fill in missing data (DMA Module, block 1620)   Exclude erroneous or biasing data points (DMA Module, block 1622)   Calculate Revenue Goal Attainment (DMA Module, block 1624)   Classify Quality Score according to Quality Heuristic (Pre-HE, block 1628)   Accumulate data and Scores to the sales-person-subject of the transaction (block 1630)  For Each Sales-Person (block 1630)   For Each Forecasting Algorithm    Calculate Forecast of remaining time units in current Sales period given past data (Block 1630)  Quality score the forecasts according to Fuzzy Logic Quality Heuristics (block 1640)  Exclude erroneous or biasing forecasted data(block 1642)  Record Consensus, High and Low forecasts for each time-division-unit. (block 1644)  Store all Forecasted values and Scores in Data Warehouse(block 1650) [0130] FIGS. 17A and 17B are a flowchart illustrating a method for scoring performance according to embodiments of the invention. A list of sales periods to analyze, a list of sales people to analyze, and/or a list of sales groups to analyze may be provided as input to the method in some embodiments. A pseudo code description of the method is as follows: [0000]  Extract ‘Goal Model’ for given Sales-Periods (Block 1702)  Extract Fuzzy Logic Quality and Priority Heuristics for given Sales-Periods(Block 1704)  For Each Sales-Period (Blocks 1706-1718)   Extract ‘Revenue Goals’ for given Sales-Period(Block 1706)   Extract Learned Revenue Profiles for given Sales-Period and all Persons/Groups(Block 1708)   Extract Idealized Revenue Profiles for given Sales-Period and all Persons/Groups(Block 1710)   Extract Learned Pipeline Analysis data for given People/Groups(Block 1712)   Extract previous learned Sales-Pipeline models for given Sales-Strategy, if any(Block 1714)   Query Sales Transaction Data for Sales-Period {Ongoing, Closed, Lost, Deferred}   (Block 1716)   Extract Seasonality Model for given Sales-Period(Block 1718)  //Data Cleaning, Data Smoothing and Heuristic Classification  For Each Sales Transaction (Blocks 1720-1726)   Use smoothing method to fill in missing data (Block 1720)   Exclude erroneous or biasing data points (Block 1722)   Classify Quality Score according to Quality Heuristic (Block 1724)   Accumulate data and Scores to the sales-person-subject of the transaction (Block 1726)  //Data Analysis (DMA Module)  For Each Sales-Person (Blocks 1730-1738)   For Each Sales-Period (Blocks 1730-1738)    Calculate Revenue Goal Attainment (Block 1730)    Classify as {Top, Average, Low}Performer (Block 1732)    Calculate Revenue Variance (Block 1734)    Calculate difference between Learned Model and Actual data (Block 1736)    Calculate difference between Idealized Model and Actual data (Block 1738)  //(DMF Module)  For Each Learning Algorithm (Blocks 1740-1746)   For n time steps (Blocks 1740-144)    Select Random Sales Person/Group (Block 1740)    If Transaction Fits Idealized Model Then reinforce Idealized Model weight (Block 1742)    If Transaction Fits Learned Model Then reinforce Learned Model weight (Block 1744)   Form Aggregate Model based upon Idealized and Learned Models (and weights) (Block 1746)  //Post-HE module  For Each Sales-Person and Group   Reclassify Person/Group according to difference between Learned   and Idealized Model as {Top    Average, Low}Performer (Block 1750)  Store all Learned Models, Scores and Classifications in Data Warehouse. (Block 1760) [0131] FIG. 18 is a flowchart illustrating a method for allocation of quotas by sales periods according to embodiments of the invention. A list of sales periods to analyze, a list of sales people to analyze, and/or a list of sales groups to analyze may be provided as input to the method in some embodiments. A pseudo code description of the method is as follows: [0000] 1. // Query Module 2. Extract Revenue Models for given Sales-Periods (Block 1802) 3. Extract Pipeline Models for given Sales-Periods (Block 1804) 4. Extract Fuzzy Logic Quality Heuristics for given Sales-Periods (Block 1806) 5. For Each Sales-Period 6.  Extract ‘Revenue Goals’ for given Sales-Period (Block 1808) 7. 8. 9. For Each Sales Period (Blocks 1810-1844) 10.  // Heuristic Classification 11.  Initialize Quotas Set for Each Person/Group Based upon current Sales Period (Block 1810) 12.  Accumulate Quotas Set to calculate a Total Quota (Block 1812) 13.  Classify Quality Score for each Quota according to Quality Heuristic (Block 1814) 14.  Classify Quality Score for Total Quota vs. Goal Quota according to Quality Heuristic (Block 1816) 15. 16.  Best-Quotas = Quotas //Each of these is a set of individual Quotas (Block 1818) 17. 18.  For n time steps (Blocks 1822 36) 19.   Quotas-New = Quotas (Block 1822) 20.   Select Random Person/Group Quota from Quotas-New (Block 1824) 21.   Randomly adjust selected Person/Groups Quota a moderate amount via White-noise function (Block 1826) 22.   Classify Quality Score for this new Quota according to Quality Heuristic (Block 1828) 23.   Classify Quality Score for Total Quota vs. Quotas-New according to Quality Heuristic (Block 1830) 24.   If Quality Score of Quotas-New ≧ Best-Quotas (Block 1832) 25.    Best-Quotas = Quotas-New (Block 1834) 26.   Else If Best-Quotas is unchanged for m time-steps (Block 1836) 27.    Add Best-Quotas and its Quality Score to Result Queue (Block 1838) 28.    n = 1 (Block 1840) 29.    Goto 11 (go to Block 1810) 30. 31.  Select a Quotas Set from Result Queue with the best Quality Score (Block 1842) 32.  Store this Quotas Set For the given Sales Period in Data Warehouse (Block 1844) 33. 34. //Quality Score of a Quota is a function of its Forecasted Revenue and Pipeline Performance vs. the 35. // overall Goals [0132] FIG. 19 is a flowchart illustrating a method for allocation of quotas by territories according to embodiments of the invention. A list of sales periods to analyze, a list of sales people to analyze, and/or a list of sales groups to analyze may be provided as input to the method in some embodiments. A pseudo code description of the method is as [0000] 1. Extract Revenue Models for given Sales-Territories (Block 1902) 2. Extract Pipeline Models for given Sales-Territories (Block 1904) 3. Extract Fuzzy Logic Quality Heuristics for given Sales-Territories (Block 1906) 4. For Each Sales-Territories 5.   Extract ‘Revenue Goals’ for given Sales-Territories (Block 1908) 6. 7. 8. For Each Sales Territories (Blocks 1910-1942) 9.  // Heuristic Classification 10.  Initialize Quotas Set for Each Person/Group Based upon current Sales Territories (Block 1910) 11.  Accumulate Quotas Set to calculate a Total Quota (Block 1912) 12.  Classify Quality Score for each Quota according to Quality Heuristic (Block 1914) 13.  Classify Quality Score for Total Quota vs. Goal Quota according to Quality Heuristic (Block 1916) 14. 15.  Best-Quotas = Quotas //Each of these is a set of individual Quotas (Block 1918) 16. 17.  For n time steps (Blocks 1920 1934) 18.   Quotas-New = Quotas (Block 1920) 19.   Select Random Person/Group Quota from Quotas-New (Block 1922) 20.   Randomly adjust selected Person/Groups Quota a moderate amount via White-noise function (Block 1924) 21.   Classify Quality Score for this new Quota according to Quality Heuristic (Block 1926) 22.   Classify Quality Score for Total Quota vs. Quotas-New according to Quality Heuristic (Block 1928) 23.   If Quality Score of Quotas-New ≧ Best-Quotas (Block 1930) 24.    Best-Quotas = Quotas-New 25.   Else If Best-Quotas is unchanged for m time-steps (Block 1932) 26.    Add Best-Quotas and its Quality Score to Result Queue (Block 1934) 27.    n = 1 (Block 1936) 28.    Goto 11 (go to Block 1910 at Block 1938) 29. 30.  Select a Quotas Set from Result Queue with the best Quality Score (Block 1940) 31.  Store this Quotas Set For the given Sales Territories in Data Warehouse (Block 1942) 32. 33. //Quality Score of a Quota is a function of its Forecasted Revenue and Pipeline Performance vs. the 34. // overall Goals EXAMPLES [0133] A series of examples illustrating the operation of the above-described systems and methods will now be provided. Example 1 Forecasting Revenue [0134] Using the data query and display module, sales data is retrieved representing some window-in-time of sales revenue as well as ongoing in-process sales records. From the DW 102 a configuration is retrieved defining the data flow and data transformed to be used. Also from the DW 102 a cache of data from the previous run(s) of the data caching and agglomeration module, metric scores and derived data from previous runs of this module is fetched. [0135] The Data Manipulation Algorithm (DMA) module 402 ( FIGS. 4 and 12 ) is applied to the raw sales data to align it with records from the ‘data cache’ using data transforms. Supplementary calculations are also made to the metric scores. An example output data stream from the module would be a large list of quantitative data associated with sales-people, sales-periods, products sold and performance metrics for each of these units. [0136] The output of this module is fed to the HE1 404 . One example function of the HE1 module 404 is to clean the data of statistical outliers before passing to the DMF module 406 . Another example is to create additional quantitative metrics. An example of this is to assign a heuristic category to individual sales people. Sales people who have consistently met or exceeded goals (as defined by evaluating any number of factors) for a large percentage of sales periods would be marked as ‘top performers’. People who meet most goals for the same time period would be marked as ‘average performers’, the rest as ‘under-performing’. A third example would flag particular metrics as having an anomaly without necessarily excluding it, such as a sales person who had his or her performance enhanced or degraded by an anomalous event and this should not unduly influence later calculations. [0137] The next sub-module in the chain is the code DMF 406 ( FIGS. 4 and 13 ). This module uses the data and metric stream as an attribute set in the combination of data models with a suite of forecasting algorithms to establish a set of revenue forecasts. An example data model would be a user-entered ideal profile of how a sales person or group's various metrics should be shaped numerically. It may contain various weights for how individual metrics would be used in forecasting algorithms. In addition other parts of the DMF module ( FIGS. 4 and 13 ) could be applied to learn a data model, or profile of how attribute values progress in time associated with performance levels, sales groups and products. This engine also is able to learn new data models with various algorithms by examining previous data in a posteriori plus feedback fashion. [0138] The output of the DMF module 406 flows to the HE2 sub-module 408 ( FIGS. 4 and 14 ). In this scenario HE2 408 would be used to take the suite of revenue forecasts and assign quality scores based upon both user entered heuristics and learned heuristics. This engine also is able to learn new heuristics with various algorithms by examining previous data in a posteriori plus feedback fashion. The final output of the example scenario is a set of revenue forecasts for each person, group and aggregate forecasts for sales. In addition accuracy scores for each forecast, as well as learned data models and heuristics are stored. Example 2 Scoring the Performance of Sales People and Groups [0139] Similar to Example 1 with the modification that all calculations are done to score the performance of individual people and groups with respect to learned data models of top-performers as well as with respect to user-entered ideal models of performance. An example of this would be an ideal revenue growth of a sales person over time. A second example is a relative analysis of the person's ongoing sales ‘pipeline’ with respect to learned and ideal models of good performance. In either case the system can learn the historical sales models for an individual or high performing sales representative using any of a variety of machine learning techniques. In addition, an idealized model can be entered by the sales manager. The resulting comparison can aid in the understanding of how individuals relate to one another and to an idealized individual. This helps sales representatives understand their relative performance, and it helps sales managers understand if there is a general deviation between their idealized model and the actual performance of an individual or group. [0140] Example 2 Details: Ideal Revenue Growth or Progression of a Sales Person Over Past Time and into the Future [0141] This analysis occurs in the MLF and DQ-DM Modules. See FIGS. 6 & 7 for diagrammatic details. The method's purpose is to extract raw data and learn a central pattern for revenue progression in time of a sales person or group that is relative to a combination of an idealized pattern and the Revenue Progression pattern of the group of Top Performers. [0142] MLF Module Operation for Example 2: [0143] The sales data for all persons groups is queried from the ‘Sales Records’ and from the Data Warehouse. Also from the Data Warehouse the various heuristics are retrieved. The Sales records consist of the ‘Closed, Lost and Deferred’ Sales Revenue for a range of hierarchical sales periods over the past X periods in time. This data is extracted per person and per group (aggregate). Individuals in the Top-Performer group are included in this query with their membership in this group tagged as such. The following heuristics are retrieved from the DW. Note that these examples are not exhaustive and one of ordinary skill in the art can easily add to this list. MLF-Module Pre-Heuristic-Engine Examples (Learned) Sales Revenue Variance: Number of sales periods where the revenue variance of an individual customer (or class or group of customers) have variance below some percentage threshold. Variance is the percentage drop or gain compared to last period. (Idealized) Sales Revenue Variance Profile: The ideal profile of revenue variance. This is characterized by a range of growth or decrease percentages period-over-period. An example would be that ideal growth or expected decrease in sales period-over-period should vary between −10% and +15% in the 3 rd month of a given year vs. the 2 nd month. (Learned) Sales Revenue Profile of Top Performers: Form an aggregate profile of the progression of the revenue profile for all ‘Top Performers’. This profile would be normalized to be a numerical curve of percentage increases starting from the initial revenue goal of the starting sales period of the analysis. The profile would be weighted by the overall ‘performance score’ of the individual. The basic computation is a smoothed weighted average using any combination of classical methods (iterative exponential smoothing) or newer time-series analysis methods with or without seasonality adjustments. (Learned) Sales Revenue Profile of Sales Group: Same as the previous analysis but using the subject-salesperson's peer-group. (Learned) Sales Revenue Profile of Sales Person: Same as previous analysis except done for each individual in isolation. (Idealized) Sales Revenue Profile: This is an idealized profile established & input by sales managers or executives that gives an ideal average and spread of a revenue curve over time. [0156] Main DMF Module Details: [0157] In this step previous learned profiles and new sales records are used to learn updated profiles. This may be accomplished by running a suite of classical forecasting methods, time series analysis methods, smoothing methods and seasonality adjustments. The outputs of the individual analysis methods are aggregated via a weighted scheme. Note that the weights of each method are learned as well. After a run is performed and forecasts are stored, they are used in the next run and compared to the actual reported revenue gained, lost, or otherwise deferred. The aggregation weights of the different methods are adjusted based upon the success or failure of the particular method's predicted data vs. actual data. [0158] The output of the DMF module ( FIG. 13 ) is processed by the MLF Post-Heuristics engine 408 ( FIG. 14 ). Here each learned profile is given a quality score that is a function of the accuracy of the predictions from the DMF module and it's similarity to the idealized models. In particular embodiments, the heuristic analysis is a set of fuzzy logic rules. [0159] Output of MLF module: Quality score for each person or group Updated ‘Learned’ profiles. Updated metadata for Idealized model-profiles. [0163] DQ-DM Module for Example 2: [0164] Given a ‘subject’ (sales representative or group) of analysis, the following is performed to display to the user a graded analysis of the subject's revenue growth or progression. See FIGS. 7 and 10 . [0165] From the DW the following can be retrieved: Run-Time profile comparison and analysis methods Learned Revenue Profile for the Subject Learned Revenue Profile for the Subject's Group Learned Revenue Profile for the Top Performers Idealized Revenue Profile. Learned Revenue Variance Profile for the Subject Learned Revenue Variance Profile for the Subject's Group Learned Revenue Variance Profile for the Top Performers Idealized Revenue Variance Profile. [0175] The run-time heuristics are performed on the above data. The Heuristics produce two types of output, comparative grading and absolute grading. The comparative grading assigns a quality score for the subjects profile relative to a comparison-group. Typically this is the subjects peer group in the organization and the group of top-performers. The absolute grading is similar except that a score is assigned assessing how well the subjects profile fits the idealized profiles. FIG. 10 has an example chart and assigned grade for an absolute revenue trend and profile analysis. One of average skill in the art can easily see other variations of this example. Example 3 Scoring Sales Processes [0176] Similar to examples 1 & 2. The module is applied to the problem of evaluating an entire sales processor sales methodology with respect to the ideal model of the process as well as compared to other good performing processes or methodologies. Note that this analysis can be independent of individuals looking at the process in isolation. It can also be used to identify weak individuals or groups that bring the overall performance of the process or methodology down. The novelty of this approach is it's usage in CRM software applied to sales process analysis and its combination with iterative machine learning methods. Example 3a Ideal Pipeline Analysis of Sales Pipeline & Strategy [0177] Background for Example 3a: [0178] A sales pipeline is an abstract construct consisting of series of ‘stages’. At each stage a set of tasks is to be performed by the sales representative. For example, stage 1 might be called ‘Leads’ where potential deals are placed in this first stage upon initial contact with the sales representative. To progress to Stage 2 (Demo Product) the deal's primary contact must exchange preliminary information with the sales representative and agree to schedule a product demonstration. Stage 7, for example, could be the ‘Negotiation’ phase where representative and client agree to financial terms of a deal. The Set of stages is generally referred to as a Sales Strategy. Representatives may be working on potential clients using a plurality of Sales Strategies. [0179] The active deals of a given representative can be assigned to a stage in a particular strategy. A representative's ‘raw pipeline’ is a set of monetary values that are the sum of the assumed value potential deals in a given stage. A representative's ‘forecasted pipeline’ is a set of values as above except that each stage is assigned a conversion rate percentage. The raw values in each stage are multiplied by the conversion rate percentage to form a set of monetary values that a representative terms his or her expected forecast. Ordinarily these percentages are manually assigned by users. [0180] Sales Strategy and Pipeline Analysis ‘Learning Method’: [0181] Various data is requested from the DW 102 and Sales Records 112 . A representative outline of this data is shown below: Closed or Lost or Deferred Revenue History Date and time of each stage transition for all deals Sales Process stages and stage-forecast-percentages Sales Goals Ongoing Active Deals Quality Heuristics Revenue Model (see Example 2) [0188] Strategy Quality Rules Data Cleaning Procedures [0189] The data above is loaded and a set of algorithms is applied to them to extract statistical information on the stage transition timings, stage abandonment rates (lost deals) and deferred or backward stage moves. All sales strategies are modeled with a multi-level queuing model such as M/M/s queuing network (for further details, see An Introduction to Stochastic Modeling, by Samuel Karlin, Howard M. Taylor, Academic Press, 3 edition (February 1998), which is hereby incorporated by reference herein for all purposes). [0190] This analysis allows the predictive modeling of the sales strategy and compares it to the user entered expected conversion rates from one stage to the next. This analysis also allows the modeling of how changing human resources allocated to specific stage will affect the behavior of the strategy as a whole. [0191] This queuing network method is combined with a set of fuzzy logic rule sets, for example, that classify deals based upon their characteristics. Specifically the attributes of a deal are used to perform a supervised machine learning algorithm based upon the outputs of the queuing model and the system learns a classification system for assigning quality scores to deals. These scores are used to prioritize attention to deals of various types. Deals that the classifier system and queuing model predict will transition quickly between stages are given an increased ‘forecast percentage’. While deals with some attribute that the ML algorithm has identified as correlated with slow progress will be assigned a lower forecast percentage. [0192] Note also that this analysis allows prediction of deal close times and assigning scoring metrics to individual sales representatives and groups based upon how a particular deal is progressing (for example—being 2 days past typical transition times in stage 2 indicates that the predicted close date will be 10 days behind typical). Another algorithm in this suite is the forecasting, smoothing and time series analysis algorithms mentioned in example 2. Here these techniques can be used to both repair missing data and to provide compatible sales strategy forecasts for comparative analysis and decisioning. It is also used to provide seasonality adjustments to the output of the queuing network. [0193] This system can be run at a frequency relevant to the typical business cycle of a sales strategy. For example, if a typical deal is closed in 30 days and some component of a deal is likely to change every day, then the system would be run at least twice a day. The data and models built from the last run are loaded and their predictions checked. The various quality weights on the output of each algorithm are adjusted by a reinforcement learning algorithm. [0194] Sales Strategy and Pipeline Analysis ‘Query, Analytic Comparison and Display Method’: [0195] FIG. 9 is an illustration of this process. It is similar to FIG. 7 . The aggregate outputs of the MLF module for this task are loaded along with the subject sales process. An example output is given on FIG. 11 . [0196] The basic method is shared with Example 2's DQ-DM section along with FIG. 7 . [0197] This following data can be loaded: [0198] From the DW the following can be retrieved: Run-Time profile of the current sales strategy. Learned forecast stage percentages Quality Metrics for poor, average and excellent performing deals Seasonality Model Data associated with the subject sales strategy Sales records for open deals within this strategy [0205] The output of this model is an aggregated summary of the open deals in the current sales period for a given sales period. Each stage in the strategy is assigned a score for overall execution and a forecasted overall conversion rate. FIG. 15 described above provides an example algorithm that details how the modules interact with each other to provide this (Example 3a) analysis. Example 3b Ideal Pipeline Analysis of Sales Representative or Group [0206] Sales Strategy and Pipeline Analysis ‘Learning Method’: Example 3b is similar to Example 3a, except that the analysis is done for a specific sales representative or group across the range of sales strategies they work on. [0208] Sales Strategy or Pipeline Analysis ‘Query, Analytic Comparison and Display Method’: See Example 3a except that this analysis is done for a specific sales representative or group across the range of sales strategies they work on. Example 4 Allocation of Quotas [0210] The system can be used to allocate or re-allocate sales goals or quotas. Using a suite of machine learning or optimization algorithm one can learn optimal allocation of quotas such that some fitness function can be maximized. The fitness function would be comprised of a weighted sum of factors and use the outputs of Example 2a as primary inputs to the fitness function to reallocate quotas. Example 5 Allocation of Territories [0211] The system can be used to allocate or re-allocate sales territories. For example, using a suite of machine learning or optimization algorithm one can learn optimal allocation of quotas such that some fitness function is maximized. The fitness function may be comprised of a weighted sum of factors and use the outputs of Example 2a as primary inputs to the fitness function to reallocate territories. [0212] The FP module 110 as supported by the DW 102 allows sales people to execute ‘what if’ scenarios for planning various organization attributes for the future. The basic idea is to solve (by isolated analysis, approximation, or by a direct technique)(in spirit, not necessarily literal solving) for a particular variable. In basic algebra when one solves equations (s), some number of variables are chosen as ‘unknown’ while the rest of the variables that are known are used to identify values and ranges of values for the unknown variables that fulfill the equations. [0213] The input to the FP 110 can be made up of the raw sales record data 112 as well as the DW 102 using all previously mentioned elements and an additional ‘scenarios’ element. The processing sub-modules are the MLF 108 , a scenario analysis engine (SAE) 502 and a display and user interface element 504 . A display and user interface components allow the user to see the output of the FP 110 as well as interact with some number of quantitative attributes. Additionally, the SAE 502 may contain specific processes as described herein. [0214] The display 504 and user interface element 116 can communicate bi-directionally with the SAE 502 & MLF 108 . The FP 110 can also store scenarios that users have created during the use of the FP 110 . One purpose of the SAE 502 and MLF 108 is to use ‘conditional’ data to create new MLF analysis outputs given this conditional data. The outputs, conditional data, and associated elements of the DW 102 are termed a ‘scenario’ and also stored in an area of the DW 102 . The scenario engine 502 contains a number of algorithms as described herein. Example 6 Goal Based Revenue Planning [0215] A manager has in mind a particular goal for a given metric, in this case goal-revenue for some number of time periods into the future. However, after looking at revenue forecasts from the MLF it is apparent that revenue forecasts are short of the goal. At this point a manager has a number of business factors that can be adjusted. Sales people's individual goals can be altered, product pricing can be adjusted and new sales people can be hired. As an example, a manager may use the system to determine which of these factors should be altered to best meet the desired goal. [0216] For example, using the FP 110 , a manager can input the desired goal-revenue and look at how factors can be altered to meet this goal. Taking one factor, as an example the individual revenue goals, the system can be asked to meet the new revenue goal by assigning new individual goals. The output here would be a breakdown of goal changes, as well as a likelihood score of the users meeting the new goals given past history and current status. It would also output an overall likelihood score of meeting the new goal-revenue. Example 7 Hiring and Firing of Individuals [0217] Building on Example 1 of the FP 110 , the manager can also attempt to meet some new goal by examining the effect of hiring additional individuals plus firing and/or replacing existing individuals. The manger is presented with a list of individuals, their past metrics, future goals and future forecasts. Each individual is also assigned various performance scores. The manger can in the simplest case eliminate individuals from the list and look at the effect on the future goals, forecasts and likelihood numbers. Another action would be to add an individual to the list of some performance level, presumable either ‘average’ or ‘top’ and look at the effect on forecasts, likelihood and goals. The third action would be the combination of the two, replacing an individual with a new individual. [0218] A slightly more complex embodiment is to set up a schedule of hiring of new people at a given performance level to see how the forecasts are affected over longer time scales. This staged hiring model would benefit from the accurate historical models of how long it took existing sales people to come up to their current level of performance and similarly indicate the growth rate for individual performance as they learn the particulars of the current product and sales environment. [0219] An embodiment of the heuristics would be both simple rule-sets as well as fuzzy rule sets to assign grades or scores to individual metrics. An embodiment of a data-model is a set of values describing how given metrics change over some other variable (an example would be a metric over time). [0220] Thus as is evident from the above, the various embodiments may provide a Revenue Forecasting system to learn to forecast revenue as a combination of standard approaches as well as ones based upon learning a profile of the members of the organization and their historical attributes, performance classification etc. [0221] Further, the various embodiments may provide for scoring the performance of Sales People and Groups, including: Scoring a person/groups learned profile against known-good profiles and entered ideal-profiles. Give detailed breakdown of areas of difference Scoring projected revenues vs. goals [0224] Still further, the various embodiments may provide analysis of performance of Sales Strategy vs. Ideal/Goal, including: Learning/building a model of Strategy-Pipeline based upon real data Comparing to Idealized model of Strategy-Pipeline Allowing prediction of pipeline throughput per person group and as a whole Providing real-time scores per person group of deviation from Ideal [0229] Yet further, the various embodiments provide the ability to perform Future Planning and What-If Scenarios, including: Goal based Revenue Planning Given learned profiles of individuals and processes what is the likelihood of meeting a particular Revenue Goal? Breakdown reallocation of Quota increases based upon above learned profiles Breakdown reallocation of Territories based upon above learned profiles Hiring/Firing Planning—Similar to above with the addition of allowing user to ask the system to evaluate the effect of adding new people, replacing people, firing people and its effect on future revenue and sales strategy performance [0235] The various sales performance and forecasting system examples shown above illustrate a novel predictive and profile learning sales automation analytics system. A user of the present invention may choose any of the above sales performance and forecasting system embodiments, or an equivalent thereof, depending upon the desired application. In this regard, it is recognized that various forms of the subject invention could be utilized without departing from the spirit and scope of the present invention. [0236] As is evident from the foregoing description, certain aspects of the present invention are not limited by the particular details of the examples illustrated herein, and it is therefore contemplated that other modifications and applications, or equivalents thereof, will occur to those skilled in the art. It is accordingly intended that the claims shall cover all such modifications and applications that do not depart from the spirit and scope of the present invention. Therefore, it is manifestly intended that this inventive subject matter be limited only by the following claims and equivalents thereof. [0237] The Abstract is provided to comply with 37 C.F.R. §1.72(b) to allow the reader to quickly ascertain the nature and gist of the technical disclosure. The Abstract is submitted with the understanding that it will not be used to limit the scope of the claims.

A sales automation system and method, namely a system and method for scoring sales representative performance and forecasting future sales representative performance. These scoring and forecasting techniques can apply to a sales representative monitoring his own performance, comparing himself to others within the organization (or even between organizations using methods described in application), contemplating which job duties are falling behind and which are ahead of schedule, and numerous other related activities. Similarly, with the sales representative providing a full set of performance data, the system is in a position to aid a sales manager identify which sales representatives are behind others and why, as well as help with resource planning should requirements, such as quotas or staffing, change.

This application is a Divisional of Ser. No. 10/682,728, filed on Oct. 9, 2003, which is now U.S. Pat. No. 7,229,647. BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to disinfectant compositions, and, more particularly, to a chlorine dioxide disinfectant composition, methods of use, and methods of making. 2. Description of Related Art Many disinfectant compositions have been known in the art, most with some degree of undesirable side effects. For example, chlorine is an inexpensive and effective disinfectant; however, being highly reactive, chlorine generates precursors of carcinogens and disinfection byproducts. Chlorine is also a powerful bleach, is highly toxic, and is largely ineffective in disinfecting gram-positive bacteria. Chlorine's functions, in order of strength, include chlorination, oxidation, bleaching, and disinfection. Ozone is primarily an oxidizer having limited disinfection capabilities in microbially contaminated water owing to its low solubility. Ultraviolet light (uv) is not effective in treating water that is microbially or biologically contaminated. Hydrogen peroxide, while being highly soluble in water, is not practical for use in water treatment. Bleach, although an effective bleaching and oxidizing agent, is highly reactive and is known to generate undesirable byproducts. Chlorine dioxide does not possess any of the above-mentioned drawbacks, and is believed especially effective in water and wastewater treatment, and in aqueous solutions. Chlorine dioxide does not incur environmental problems or health concerns, and does not generate disinfection byproducts (DBPs), except for a small amount of chlorite ion (ClO 2 − ) as an intermediate that spontaneously decomposes into harmless products, chloride ion (Cl − ) and oxygen. Further, chlorine dioxide does not create chlorinated organics, including precursor materials of trihalomethanes (THMs), unlike chlorine. Chlorine dioxide is approximately five times more soluble than chlorine in water and direct exposure to the gas is much less harmful than to chlorine at similar concentrations. In addition, chlorine dioxide is very effective in disinfecting gram-positive bacteria, which cannot be treated effectively by other known disinfectants. If used properly in its pure form, chlorine dioxide can produce residuals at an exit stream of a treatment system similar to those of chlorine, and is effective in reducing turbidity, discoloring, and deodorizing. Chlorine dioxide made by prior art methods is known to be contaminated with free available chlorine (FAC), chlorite ion, chlorate ion, chloride ion, and hypochlorite ion, arising from process raw materials, process intermediates, and synthesis byproducts. Even if the contaminant concentrations are low, they may affect subsequent disinfection chemistry, as well as the stability of the chlorine dioxide product via a variety of chemical reactions, including oxidation-reduction reactions, as well as autocatalytic reactions. Some of these reactions include, but are not intended to be limited to: Cl 2 +H 2 O HClO+HCl HClO H + +ClO − ClO 2 +ClO − +e − 2Cl − +3/2O 2 ClO 2 +ClO 2 − +e − 2Cl − +2O 2 ClO 2 +e − Cl − +O 2 ClO 3 − ClO 2 − +(O) ClO 2 +(O) Cl − + 3/2O 2 The presence of other oxychloro compounds in the chlorine dioxide aqueous solution can lead to many other chemical reactions that are undesirable for the intended objects of the product. Such reactions not only create harmful byproducts, but also can cause the premature decomposition of the product chlorine dioxide. Chlorine dioxide is not stable as a product gas, being susceptible to uv and to self-decomposition into chlorine and oxygen. Therefore, chlorine dioxide has typically been in aqueous solution, limiting its applications. Even in aqueous solution chlorine dioxide is unstable, further limiting its use as a liquid product. Owing to its instability, chlorine dioxide has never been approved as a transportation chemical by the U.S. Department of Transportation or the United Nations. Thus on-site generation has been the only means for utilizing chlorine dioxide, which must be used within a day or two at most, 80-90% of its strength typically lost within 24 hours. The decomposition mechanisms have not until now been understood. Decomposition of chlorine dioxide may be attributed to six possible causes: 1. Chlorine dioxide exhibits vapor-phase (or dry-phase) decomposition. 2. Gas-phase decomposition of chlorine dioxide is promoted in the presence of air, specifically, oxygen. In aqueous solution, the dissolved oxygen concentration being only ˜9.2 mg/L, decomposition is less. 3. Decomposition in both the dry and wet phases is also promoted in the presence of other strong oxidants and reducing agents. Although chlorine dioxide is generally an oxidant, it can function as a reducing agent when in contact with a stronger oxidizer. Therefore, any impurities in the product stream or solution would participate in a chemical reaction, including decomposition of chlorine dioxide. Once decomposition begins, the decomposition products, including oxygen, act to promote further decomposition reactions. Such an accelerated reaction is termed “autocatalytic,” meaning that the undesirable reactions are self-sustaining, eventually leading to substantially complete decomposition of the chlorine dioxide in the system. 4. Chlorine dioxide decomposition is promoted by uv irradiation, since the molecules readily absorb radiation. 5. Chlorine dioxide decomposition is very strongly promoted by mechanical agitation or shock, which can be compounded by oxygen-triggered decomposition as described in (2) above, since mechanical agitation can create air pockets and increase the concentration of dissolved oxygen in the water. 6. Chlorine dioxide decomposition is greater in a container having a large headspace, driven by the vapor pressure of chlorine dioxide, promoting movement from the aqueous phase to the vapor phase. Pure chlorine dioxide is known to be produced by the system and method of commonly owned U.S. Pat. Nos. 5,855,861 and 6,051,135, the contents of which are incorporated herein by reference. There are, however, no known systems, compositions, or methods for achieving long-term storage and preservation of pure chlorine dioxide, which would be desirable. SUMMARY OF THE INVENTION The present invention is directed to a stable chlorine dioxide composition, its method of making, and method of use, for achieving long-term storage and subsequent release when desired. The invention includes a method of making a composition having the property of being able to store chlorine dioxide, preferably for long periods. The method comprises the steps of mixing an aqueous chlorine dioxide solution with a superabsorbent, water-soluble polymer that is substantially unreactive with chlorine dioxide and permitting a mixture formed thereby to form one of a gel and a solid composition. The composition comprises the gel or solid composition formed thereby. The solid composition may be made into pellets or tablets, for example. A method of delivering chlorine dioxide comprises the steps of providing a gel or solid composition as described above and degelling the gel or dissolving the solid composition to dispense the chlorine dioxide therefrom. A method of disinfecting a target such as water, wastewater, or a surface comprises the steps of delivering chlorine dioxide by providing and degelling the gel or dissolving the solid composition as above, and permitting the polymer to precipitate out. Aqueous chlorine dioxide is then recovered from a supernatant above the precipitate, and the recovered aqueous chlorine dioxide is applied to the target. The features that characterize the invention, both as to organization and method of operation, together with further objects and advantages thereof, will be better understood from the following description used in conjunction with the accompanying drawing. It is to be expressly understood that the drawing is for the purpose of illustration and description and is not intended as a definition of the limits of the invention. These and other objects attained, and advantages offered, by the present invention will become more fully apparent as the description that now follows is read in conjunction with the accompanying drawing. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 graphs chlorine dioxide concentration versus time for series of polymer gels for Example 3. FIG. 2 graphs chlorine dioxide concentration versus time for series of polymer gels for Example 4. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A description of the preferred embodiments of the present invention will now be presented with reference to FIGS. 1 and 2 . The present invention is directed to a stable chlorine dioxide gel or solid composition, its method of making, and method of use, for achieving long-term storage and subsequent release when desired. The invention is also directed to a method of disinfecting a target, such as, but not intended to be limited to, water, wastewater, or a surface. Broadly, the gel and solid composition of the present invention are made by absorbing substantially byproduct-free and FAC-free, pure aqueous chlorine dioxide solution in a superabsorbent or water-soluble polymer that is nonreactive with chlorine dioxide in a substantially oxygen-free environment. If the product is a gel, the gel retains a color substantially identical with that of the original chlorine dioxide solution, that is, yellowish-green for 200-600 mg/L, bright green for 1000-2500 mg/L, and dark green to greenish brown for >5000 mg/L. As tested thus far, product gel retains its consistency for more than a year, essentially permanently under a controlled environment, retaining the chlorine dioxide concentration at 80% or higher for at least 6 months at room temperature. The gel and solid compositions of the present invention are believed to retain chlorine dioxide by “locking” the chlorine dioxide molecules in an inert and innocuous solid matrix such as a gel or tablet. Such a matrix limits the mobility of the thus-entrapped molecules, making them less susceptible to mechanical shock, protects against uv or ir radiation, and limits air/oxygen penetration. The gel should not have microbubbles or air globules present, and preferably the amount of polymer material required should be sufficiently small so as to make the resulting product cost-effective. Any decomposition that does occur should preferably yield only harmless chloride ion and oxygen. For example, ClO 2 (aq. gel)+organics, impurities ClO 2 − (aq. gel) ClO 2 − (aq. gel) Cl − +O 2 Although the gel form of the product is believed to represent the preferred embodiment, the composition may also comprise a tablet in an alternate embodiment of a solid composition. Such a tablet is created by substantially the same method as for the gel; however, a greater proportion of the superabsorbent polymer is used, e.g., ≧50 wt. %, with ≦50 wt. % ClO 2 added. The superabsorbent polymer of the present invention should not be able to undergo an oxidation reaction with chlorine dioxide, and should be able to liberate chlorine dioxide into water without any mass transfer resistance. Nor should byproduct be releasable from the gel in contact with fresh water. Exemplary polymers may comprise at least one of a sodium salt of poly(acrylic acid), a potassium salt of poly(acrylic acid), straight poly(acrylic acid), poly(vinyl alcohol), and other types of cross-linked polyacrylates, such as polyacrylimide and poly(chloro-trimethylaminoethyl acrylate), each being preferably of pharmaceutical grade. A molecular weight range is preferably 5,000-150,000, and more preferably 15,000-40,000 for forming a gel, and ≧50,000 for forming a solid composition. It is believed that sodium salts are preferable to potassium salts for any potential byproduct release, although such a release has not been observed. The amount of polymer required to form a stable gel is in the order of sodium and potassium salts of poly(acrylic acid)<straight poly(acrylic acid)<poly(vinyl alcohol). The order of stability is in reverse order, however, with very little difference among these polymer types. The gel of the present invention is formed by mixing a mass of the polymer into the aqueous chlorine dioxide solution in an amount preferably less than 5-10%, most preferably in range of approximately 0.5-5%, and stirring sufficiently to mix the components but sufficiently mildly so as to minimize the creation of agitation-produced bubbles. Gelling efficiency varies among the polymers, with the poly(acrylic acid) salts (Aridall and ASAP) forming gels more quickly with less polymer, a ratio of 100:1 solution:resin sufficient for making a stable gel; straight poly(acrylic acid) requires a ratio of 50:1 to make a similarly stable gel. The stabilities here refer to mechanical and structural, not chemical, stability. The gelling process typically takes about 0.5-4 min, preferably 2 min, with a minimum time of mixing preferable. Gels can be produced without mixing; however, mild agitation assists the gelling process and minimizes gelling time. It has been found that 1 g of polymer can be used with as much as 120 g of 2000-ppm pure chlorine dioxide solution. Concentrations of at least 5000 ppm are achievable. Any bubbles that are produced are found to be very stable, taking 2-3 weeks to migrate to the top of a container, which is 6-7 orders of magnitude slower than bubbles in an aqueous chlorine dioxide solution. Preferably the mixing is carried out in a substantially air/oxygen-free environment in a closed container, possibly nitrogen-purged. Storage of the formed gel should be in sealed containers having uv-blocking properties is preferred, such containers comprising, for example, uv-blocking amber glass, opaque high-density polyethylene, chlorinated poly(vinyl chloride) (CPVC), polytetrafluoroethylene-lined polyethylene-(PTFE) lined polyethylene, cross-linked polyethylene, polyvinyl chloride, and polyvinylidenefluoride (PVDF), although these are not intended to be limiting. The gel of the present invention was found to be very effective in preserving chlorine dioxide concentration for long periods of time, in sharp contrast to the 1-2 days of the aqueous solution. The clean, bright green color of the gel is retained throughout storage, and did not substantially degas as found with aqueous solutions of similar concentration. For example, a 400-ppm aqueous solution produces a pungent odor that is not detectable in a gel of similar concentration. The straight PAA gels made from Carbopol (Polymer C; Noveon, Inc., Cleveland, Ohio) were found to achieve better preservation than the PAA salt types. Additional resins that may be used include, but are not intended to be limited to, Aridall and ASAP (BASF Corp., Charlotte, N.C.), and poly(vinyl alcohol) (A. Schulman, Inc., Akron, Ohio). The liberating of aqueous chlorine dioxide from the gel material is performed by stirring the gel material into deionized water, and sealing and agitating the mixing vessel, for example, for 15 min on a low setting. Polymer settles out in approximately 15 min, the resulting supernatant comprising substantially pure aqueous chlorine dioxide. The gellant is recoverable for reuse. Aqueous chlorine dioxide is liberated from a tablet by dissolving the tablet into deionized water and permitting the polymer to settle out as a precipitate. The resulting aqueous chlorine dioxide may then be applied to a target, such as, but not intended to be limited to, water, wastewater, or a surface. In order to minimize decomposition, both spontaneous and induced, the components of the gel and solid composition should be substantially impurity-free. As an example, the chlorine dioxide solution may be provided by use of the method of the 861 and 135 patents referred to above. Exposure to air/oxygen and uv and ir radiation should be minimized, as should mechanical shock and agitation. Laboratory data are discussed in the following four examples. Example 1 Two types of polymer, the sodium and potassium salts of poly(acrylic acid), were used to form gels. The aqueous chlorine dioxide was prepared according to the method of the 861 and 135 patents, producing a chlorine dioxide concentration of 4522 mg/L, this being diluted as indicated. The gels were formed by mild shaking for 2 min in an open clock dish, the gels then transferred to amber glass bottles, leaving minimum headspace, sealed, and stored in the dark. The aqueous controls were stored in both clear and amber bottles. After 3 days it was determined that the gels retained the original color and consistency, and were easily degelled. Table 1 provides data for 3 and 90 days, illustrating that little concentration loss occurred. The samples after 3 days were stored under fluorescent lighting at approximately 22° C. TABLE 1 Chlorine Dioxide Gels in 3- and 90-Day Storage, Concentrations in ppm ClO 2 Polymer Initial ClO 2 Conc. ClO 2 Amt. Amt. ClO 2 After 3 Conc. After Prod. Container (ml) (g) Conc. Days 90 Days Form Aqueous Soln. Clear Bottle 35 — ~420 ~60 ~0 Soln. Aqueous Soln. Amber Bottle 35 — ~420 ~370 ~70 Soln. Polymer BA1-1 Amber Bottle 35 0.25 ~400 ~390 ~380 Gel Polymer BA1-2 Amber Bottle 35 0.30 ~380 ~350 ~350 Gel Polymer BA2-1 Amber Bottle 35 0.25 ~380 ~350 ~330 Gel Polymer BA2-2 Amber Bottle 35 0.30 ~380 ~360 ~355 Gel BA1: Sodium polyacrylate, ASAP ™ (BASF) BA2: Potassium polyacrylate, Aridall ™ (BASF) From these data it may be seen that, even when stored in a tightly sealed, amber bottle, the aqueous solution loses strength rapidly, although the amber bottle clearly provides some short-term alleviation of decomposition. Also, even with a 0.71% proportion of gelling material, a stable gel was formed. The gels, in the order presented in Table 1, retained 97.4, 100, 94.3, and 98.6% of their strength at 3 days after 90 days. The two polymers provided essentially equal effectiveness. The gels apparently protected against uv-mediated decomposition. The gels are also far more effective in preserving chlorine dioxide concentration. The gels were shown to preserve their original color during the storage period. Analysis after 90 days proved that the degelled solution contained only chlorine dioxide and a very small amount of chloride ion. Example 2 Gels formed by five different polymers, each having their formed gels stored in clear and amber containers, were compared when stored under different conditions. Table 2 provides the results of these experiments. TABLE 2 Results of Experiments of Example 2 # of Days 10 14 21 28 32 39 51 102 CONTROL 1 407 414 380 332 312 282 288 277 STDEV 0.0 11.7 12 5.9 11.7 5.9 5.9 6.6 CONTROL 2 332 271 278 261 265 292 282 280 STDEV 11.7 23.5 12 5.9 10.2 11.7 15.5 10.0 CONTROL 3 286 241 229 225 221 233 225 219 STDEV 0.0 0.0 0.0 6.6 6.6 6.6 6.6 5.9 HALF 331 292 280 235 254 263 205 144 BOTTLE STDEV 25.7 11.6 9 10.4 10.2 12.6 7.8 7.1 Polymer A 257 248 236 214 208 208 201 197 STDEV 12.8 7.4 7 14.8 6.4 9.8 7.4 8.8 Polymer B 228 216 208 196 198 194 192 184 STDEV 0.0 0.0 7 6.9 12.0 6.9 12.0 6.5 Polymer C-1 317 283 278 266 270 278 270 271 STDEV 7.4 12.8 7 7.4 11.1 7.4 12.9 10.2 Polymer C-2 287 291 287 261 257 259 257 254 STDEV 7.4 7.4 7 7.4 0.0 3.7 0.0 4.9 PPM lost due 46 31 49 36 43 59 56 61 to separation of polymer (CONTROL 2- CONTROL 3) Average = 48 CONTROL 1: Full amber bottle with polymer (no agitation) CONTROL 2: Full amber bottle prepared with polymer samples (agitated for 15 min) CONTROL 3: Full amber bottle prepared with polymer samples (agitated for 15 min) and analyzed with polymer samples (diluted and agitated for 15 min) HALF: Half-filled amber bottle POLYMER A: Sodium polyacrylate, ASAP (BASF); full amber bottle with 0.25 g ASAP (agitated 15 min for preparation and diluted and agitated 15 min for analysis) POLYMER B: Potassium polyacrylate; full amber bottle with 0.30 g Aridall (BASF) (agitated 15 min for preparation and diluted and agitated 15 min for analysis) CARBOPOL C-1: Poly(acrylic acid); full amber bottle with 0.50 g Carbopol ® 974 (Noveon) (agitated 15 min for preparation and diluted and agitated 15 min for analysis) CARBOPOL C-2: Poly(acrylic acid); Full amber bottle with 0.75 g Carbopol ® 971 (Noveon) (agitated 15 min for preparation and diluted and agitated 15 min for analysis) The half-bottle results indicate that stability was significantly lower than in full-bottle samples under substantially identical preparation and storage conditions, the difference being even more pronounced with longer storage times, illustrating the decomposition effect triggered by gas-phase air. Even in the half-bottle gels, however, storage effectiveness is still 100-200 times that of conventional solution storage. Example 3 High-concentration (1425 ppm) aqueous chlorine dioxide was used to form polymer gels as listed in Table 3 in this set of experiments, the results of which are given in Table 4 and FIG. 1 . The initial loss of concentration strength is due to dilution and procedural exposure, during preparation and analysis, to ambient air, not to decomposition based upon interaction between the polymer and the chlorine dioxide. TABLE 3 Sample Preparation Information for Gel Technology (High Concentration) Samples Bottle Gellant HDA Amber Polymer A HDB Amber Polymer B HDC Amber Polymer C-1 HDD Amber Polymer C-2 HDE Amber Polymer C-3 HDF Amber Control 1 HDG Amber Control 2 HDH Amber Control 3 HDI Clear Polymer A HDJ Clear Polymer B HDK Clear Polymer C-1 HDL Clear Polymer C-2 HDM Clear Polymer C-3 HDN Clear Control 1 HDO Clear Control 2 HDP Clear Control 3 Note: All sample bottles are full, and stored at room temperature under fluorescent light. TABLE 4 ClO 2 Analysis Data of ClO 2 Gels TRT Initial 4 d 9 d 25 d 57 d 90 d Series HDA 1425 13060 97124 97912 8030 6700 6700 1 HDB 1425 12720 9370 92912 8370 8370 61924 3 HDC 1425 129712 108824 10710 108824 98824 72024 5 HDD 1425 129712 103847 10550 9710 92124 77047 7 HDE 1425 12250 10260 101023 9730 94423 77823 9 HDF 1425 141417 122717 12150 12340 11690 11 HDG 1425 127523 10930 108412 10590 10930 13 HDH 1425 127523 100212 101023 9930 9930 15 HDI 1425 135812 8060 79812 7010 4560 17 HDJ 1425 132312 89425 89425 7710 38650 19 HDK 1425 13500 97312 97312 9110 5960 21 HDL 1425 135812 96425 9460 9320 5960 23 HDM 1425 130612 10170 99925 8410 5610 25 HDN 1425 141417 113317 11220 11220 91133 27 HDO 1425 135025 99012 9820 9820 8060 29 HDP 1425 135025 114812 11570 10170 96425 31 Note: Data in the first row for each sample are averages, while those on the second row are standard deviations. Sample designations as in Table 3. The data indicate that the gels are quite stable for a long period of time. In most cases the gels retained their strength at 50% or higher even after 90 days, which is believed to represent a technological breakthrough. Amber bottles are clearly more effective in preserving chlorine dioxide concentration, especially until the 60-day mark. Some late-stage decline may be attributable to seal failure, the seals used in these experiments comprising paraffin, which is known to be unreliable with regard to drying, fracture, pyrolytic evaporation, and puncture, and some of this failure was observable to the naked eye. The high-molecular-weight polymer, poly(acrylic acid) (polymer C) was more effective than its lower-molecular-weight counterparts, the PAA salts (polymers A and B), indicating that higher-molecular-weight polymers provide better structural protection and “caging” for chlorine dioxide molecules against uv and air. Example 4 The long-term stability of the gels of the present invention was tested using a set of gels prepared from three different types of water-soluble polymers. The prepared samples were kept in a ventilated cage with fluorescent light on full-time at room temperature. The gel samples were sealed tightly in amber bottles with paraffinic wax and wrapped with Teflon tapes for additional protection. Five identical samples using each polymer type were prepared, and one each was used for analysis at the time intervals shown in Table 5 and FIG. 2 . TABLE 5 Long-term Stability of Chlorine Dioxide Gels 0 mo. 3 mo. 6 mo. 12 mo. Polymer A 1227 1154 1144 956 Polymer B 1227 1147 1140 924 Polymer C-1 1227 1177 1173 1085 Polymer C-2 1227 1180 1170 1079 Polymer C-3 1227 1181 1173 1096 Polymers A and B were added at 0.8% of the solution mass, with Polymer C added at 2%, to achieve optimal gelling concentration for each individual polymer. All the samples indicate long-term chlorine dioxide product stability previously unachievable in the art. The gels made from polymer C were better in long-term preservation of chlorine dioxide than those made using polymers A and B, which may be attributable to its higher average molecular weight, as well as to the greater amount of polymer used per unit volume. Therefore, it will be appreciated by one of skill in the art that there are many advantages conferred by the present invention. Chlorine dioxide is preserved at least 200, and up to 10,000, times longer than previously possible in aqueous solution. Off-site manufacturing and transport now becomes possible, since the composition is unaffected by vibration and movement, is resistant to uv and ir radiation, to bubble formation, and to oxygen penetration, and reduces vapor pressure. The composition has substantially reduced risks from inhalation and skin contact. The applications of the present invention are numerous in type and scale, and may include, but are not intended to be limited to, industrial and household applications, and medical, military, and agricultural applications. Specifically, uses may be envisioned for air filter cartridges, drinking water, enclosed bodies of water, both natural and manmade, cleansing applications in, for example, spas, hospitals, bathrooms, floors and appliances, tools, personal hygiene (e.g., for hand cleansing, foot fungus, gingivitis, soaps, and mouthwash), and food products. Surfaces and enclosed spaces may be cleansed, for example, against gram-positive bacteria, spores, and anthrax. It may be appreciated by one skilled in the art that additional embodiments may be contemplated without departing from the spirit of the invention. In the foregoing description, certain terms have been used for brevity, clarity, and understanding, but no unnecessary limitations are to be implied therefrom beyond the requirements of the prior art, because such words are used for description purposes herein and are intended to be broadly construed. Moreover, the embodiments of the composition and associated methods described herein are by way of example, and the scope of the invention is not limited to the exact details disclosed.

A method of making a composition having the property of being able to store chlorine dioxide includes mixing an aqueous chlorine dioxide solution with a superabsorbent, water-soluble polymer that is substantially unreactive with chlorine dioxide and permitting a mixture formed thereby to form one of a gel and a solid composition. A method of delivering chlorine dioxide includes providing a gel or solid composition as described and degelling the gel or dissolving the solid composition to dispense the chlorine dioxide therefrom. A method of disinfecting a target such as water, wastewater, or a surface comprises delivering chlorine dioxide as above and permitting the polymer to precipitate out of the mixture. Aqueous chlorine dioxide is then recovered and applied to the target.

BACKGROUND Technical Field The present invention relates to a process for manufacturing a lid for an electronic device package, to a process for manufacturing a packaged microelectromechanical device, to a lid for an electronic device package, and to a packaged microelectromechanical device. Description of the Related Art MEMS (microelectromechanical systems) devices find increasingly extensive use in a wide range of sectors as miniaturized sensors or transducers. For example, microphones and pressure sensors are frequently used in mobile communication devices and filming apparatuses, such as cell phones and video cameras. Given that the extremely marked miniaturization of MEMS devices entails a certain fragility of micromechanical structures, it is common to use protective lids that encapsulate the parts more readily subject to failure. Normally, MEMS sensors or transducers are mounted on substrates, possibly with control circuits. The substrates are coupled to respective lids and form packages within which the devices to be protected are located. The protective lids also perform other functions, in addition to that of mere mechanical barrier. In particular, in many cases, the transmission of the signals may be disturbed by the environment, and hence it is necessary to envisage a protection from light and electromagnetic interference. For this purpose, the cavities of the lids are coated internally by metal shielding layers. The lids may moreover have the function of determining optimal conditions of acoustic pressure for operation of the MEMS sensors. The protective lids are in general bonded to the substrate on which the MEMS sensors are mounted by conductive glues, which enable grounding of the electromagnetic shielding layer. Soldering pastes, for example with a base of tin-lead, tin-aluminum-copper, or tin-antimony, would in themselves be preferable to conductive glues, especially on account of the better resistance to impact demonstrated by the results of drop tests. However, soldering pastes melt during the steps of assembly of a package (comprising supporting board, MEMS sensor, and lid) to the boards of the electronic system in which the MEMS sensor is to be used. Molten soldering pastes tend to climb up the vertical conductive walls of the lid, invading the cavities in which the MEMS sensor is housed and leaving empty spaces in the soldering joints. The empty spaces in the soldering joints are particularly undesirable, because, on the one hand, they weaken soldering and, on the other, may cause leakages that affect the performance of the devices, especially when a controlled-pressure reference chamber is desired. There is thus felt the need to allow the use of soldering pastes in the production of packaged electronic devices comprising microelectromechanical structures. BRIEF SUMMARY One or more embodiments of the present invention is to provide a process for manufacturing a lid for an electronic device package, a process for manufacturing a packaged microelectromechanical device, a lid for an electronic device package, and a packaged microelectromechanical device that allow to overcome the limitations described and, in particular, enable use of soldering pastes eliminating or at least reducing the risk of migration of molten soldering paste in cavities for housing the microelectromechanical devices during final assembly. According to various embodiments of the present invention a process for manufacturing a lid for an electronic device package, a process for manufacturing a packaged microelectromechanical device, a lid for an electronic device package, and a packaged microelectromechanical device are provided. BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS For a better understanding of the invention, some embodiments will now be described, purely by way of non-limiting example and with reference to the attached drawings, wherein: FIG. 1 shows a cross section through a first substrate, in an initial step of a process for manufacturing a packaged microelectromechanical device according to one embodiment of the present invention; FIG. 2 shows the first substrate of FIG. 1 in a subsequent processing step; FIG. 3 shows a cross section through a second substrate in a step of the process; FIG. 4 shows a cross section through a lid according to one embodiment of the present invention, obtained by joining the first substrate of FIG. 2 and the second substrate of FIG. 3 ; FIGS. 5-7 show the lid of FIG. 4 in successive steps of the process; FIG. 8 is a cross section of a third substrate in a step of the process; FIG. 9 shows a cross section through a composite structure obtained in an intermediate step of the process, by joining the lid of FIG. 7 and the composite structure of FIG. 8 ; FIG. 10 shows the composite structure of FIG. 9 in a subsequent step of the process; FIG. 11 shows a packaged microelectromechanical device according to one embodiment of the present invention in a final step of the process; FIG. 12 is a cross section through a packaged microelectromechanical device, obtained by a process according to a different embodiment of the present invention; FIG. 13 is a cross section through a lid according to one embodiment of the invention, incorporated in the packaged microelectromechanical device of FIG. 12 ; FIG. 14 is a cross section through a substrate, in an initial step of a process for manufacturing a packaged microelectromechanical device according to one embodiment of the present invention; FIG. 15 shows a cross section through a lid according to one embodiment of the present invention, obtained from the substrate of FIG. 14 ; FIG. 16 shows a packaged microelectromechanical device according to one embodiment of the present invention in a final step of the process; FIG. 17 is a block diagram of a packaged microelectromechanical device; and FIG. 18 is a block diagram of an electronic system incorporating the packaged microelectromechanical device of FIG. 16 . DETAILED DESCRIPTION In an initial step of a process for manufacturing a packaged microelectromechanical device, to which FIG. 1 refers, a first face 1 a and a second face 1 b of a first protective substrate 1 are coated, respectively, with a first conductive layer 2 a and a second conductive layer 2 b , both made of metal, in particular copper. In one embodiment, the first protective substrate is made of an organic material, for example bismaleimide triazine (BT). Moreover, an adhesive layer 3 is laminated on the second conductive layer 2 b. Next ( FIG. 2 ), a through cavity 5 is formed in the first conductive layer 2 a , in the first protective substrate 1 , in the second conductive layer 2 b , and in the adhesive layer 3 , for example by through punching. As illustrated in FIG. 3 , a second protective substrate 7 , which has a smaller thickness than the first protective substrate 1 and is made of the same material, is prepared separately. In particular, a first face 7 a and a second face 7 b of the second protective substrate 7 are coated with a third conductive layer 8 a and with a fourth conductive layer 8 b , made, for example, of the same material used for the first conductive layer 2 a and for the second conductive layer 2 b , which in the embodiment described is copper. The first protective substrate 1 is then bonded to the second protective substrate 7 (more precisely to the third conductive layer 8 a ) through the adhesive layer 3 , as illustrated in FIG. 4 . In this way, a lid 9 is obtained, in which the first protective substrate 1 and the second protective substrate 7 form, respectively, side walls 5 a and a covering of the cavity 5 on a side opposite to the first face 1 a of the first protective substrate 1 . After the first protective substrate 1 and the second protective substrate 7 have been bonded, the lid 9 is coated internally with conductive material by a process of plating, followed by a process of electrodeposition ( FIG. 5 ). In one embodiment, the conductive material is the same as the one used for forming the first layer 2 a , the second layer 2 b , and the third conductive layer 8 a , in particular copper. Residual portions of the first layer 2 a and of the second layer 2 b and the third conductive layer 8 a hence remain incorporated in a shielding layer 10 . The shielding layer 10 coats the first face 1 a of the first protective substrate 1 and the walls of the cavity 5 , i.e., the side walls 5 a and a portion of the first face 7 a of the second protective substrate 7 facing the cavity 5 . Next, the lid 9 is washed and a protective organometal layer 11 made of organic surface protection (OSP) material is deposited on the shielding layer 10 before the surface of the shielding layer 10 itself is oxidized with copper (II) oxide (CuO). Following upon washing, in fact, a layer of copper (I) oxide (Cu 2 O) is formed on the surface of the shielding layer 10 and tends in a short time to oxidize further into copper (II) oxide. The protective organometal layer 11 is formed both within the cavity 5 (on the side walls 5 a and on the portion of the first face 7 a of the second protective substrate 7 facing the cavity 5 ) and on the first face 1 a of the first protective substrate 1 . In one embodiment, in particular, the protective organometal layer 11 is made of a one-pass OSP material. OSP materials, which are commonly used in the production of printed circuits, are obtained by depositing substances such as imidazole and imidazole derivatives, which, in contact with copper, form organometal compounds capable of preventing oxidation of the surface copper. OSP materials are can be removed thermally or else chemically, for example in acid. In the family of OSP materials, one-pass OSP materials form organometal compounds that present greater ease of removal by thermal cycles. In particular, the organometal compounds formed by one-pass OSP materials are substantially removed if subjected to the thermal stress determined by a single cycle of soldering during printed-circuit-board assembly. In one embodiment, the OSP material is obtained by depositing benzotriazole, which forms a compound of Cu(I) benzotriazole. The protective organometal layer 11 thus prevents oxidation of the shielding layer 10 . Processing of the second protective substrate 7 is then completed with opening of a through sound port 12 ( FIG. 7 ) so as to set the cavity 5 in communication with the outside world after closing of the lid 9 with another substrate. It is to be appreciated that various steps of the method may be performed sequentially, in parallel, omitted or in an order different from the order that is described and illustrated. A supporting substrate 13 ( FIG. 8 ), mounted on which are a first chip, integrating a MEMS acoustic transducer 15 (for example, with capacitive variation), and a second chip, integrating an ASIC (application-specific integrated circuit) control circuit 16 , is prepared separately by deposition of a layer of soldering paste 17 , for example with a base of tin-lead, tin-aluminum-copper, or tin-antimony, on a soldering surface. The supporting substrate 13 is a composite substrate made of organic material, for example BT, and comprises conductive paths 18 set on a plurality of levels and connected by interconnections 19 (represented purely by way of example). The MEMS acoustic transducer 15 and the control circuit 16 are mounted on a face 13 a of the supporting substrate 13 to be fitted to the lid 9 . The layer of soldering paste 17 extends over the face 13 a of the supporting substrate 13 around the MEMS acoustic transducer 15 and the control circuit 16 . The lid 9 is then joined to the supporting substrate 13 as illustrated in FIG. 9 , with the protective organometal layer 11 in contact with the layer of soldering paste 17 so that the MEMS acoustic transducer 15 and the control circuit 16 remain housed in the cavity 5 . The lid 9 and the supporting substrate 13 are heated until melting of the layer of soldering paste 17 is obtained ( FIG. 10 ). The protective organometal layer 11 is thermally destroyed and releases the shielding layer 10 , enabling formation of a conductive soldering joint 20 with the shielding layer 10 itself. In particular, where the protective organometal layer 11 is in contact with the shielding layer 10 , the soldering paste penetrates into the protective organometal layer 11 , which is destroyed. The OSP material of the protective organometal layer 11 is removed by a flux that is contained in the soldering paste or, alternatively, is deposited prior to soldering. Within the cavity 5 the protective organometal layer 11 vaporizes. The molten soldering paste rises by capillarity into the protective organometal layer 11 also for a short stretch along the shielding layer 10 within the cavity 5 . Penetration within the cavity 5 is, however, negligible. A packaged microelectromechanical device 25 , in particular a MEMS microphone, is thus formed, comprising the MEMS acoustic transducer 15 , the control circuit 16 , and a package 24 , forming part of which are the lid 9 and the supporting substrate 13 . Finally, the shielding layer 10 , in direct contact everywhere with the atmosphere present in the cavity 5 , is coated with a protective layer of copper (II) oxide 26 . Advantageously, the protective layer of copper (II) oxide 26 is permanent and has a very low wettability. For this reason, also during subsequent steps of assembly of the packaged microelectromechanical device 25 to a printed-circuit board, given that the molten soldering paste is unable to climb up the shielding layer 10 , which is protected by the protective layer of copper (II) oxide 26 , it remains confined in the region of the soldering joint 20 and does not invade the cavity 5 . It is thus possible to use soldering paste instead of conductive glues, without any need to resort to costly solutions, such as Ni-Au plating processes. According to the embodiment illustrated in FIG. 12 , a packaged microelectromechanical device 125 , in particular a MEMS microphone, comprises a MEMS acoustic transducer 115 , integrated in a first chip, a control circuit 116 , integrated in a second chip, and a package 124 . The package 124 comprises a lid 109 and a supporting substrate 113 , on which the MEMS acoustic transducer 115 and the control device 116 are mounted. The lid 109 , obtained by bonding a first protective substrate 101 and a second protective substrate 107 , has a blind cavity 105 and is without through openings. The supporting substrate 113 has a through opening that is formed previously and is in fluid communication with the MEMS acoustic transducer 115 and defines a sound port 112 . In this case, the cavity 105 defines a reference chamber for the MEMS acoustic transducer 115 . Moreover, a copper shielding layer 110 coats the walls of the cavity 105 and a face 101 a of the first protective substrate 101 bonded to the supporting substrate 113 . The packaged microelectromechanical device 125 is obtained as already described, except for the fact that the sound port 112 is obtained in the supporting substrate 113 instead of in the lid 109 . In particular, in a step of the process of production, the lid 109 , prior to being joined to the supporting substrate 113 , is coated with a protective organometal layer 111 made of OSP material, as illustrated in FIG. 13 . When the lid 109 and the supporting substrate 113 are bonded by a layer of soldering paste 117 , the protective organometal layer 111 made of OSP material is thermally destroyed and exposes the shielding layer 110 both on the face 101 a of the first substrate 101 and in the cavity 105 . The layer of soldering paste 117 melts and forms a soldering joint 120 . The atmosphere present in the cavity 105 causes oxidation of the copper in the exposed portions of the shielding layer 110 , which are thus coated with a protective layer of copper (II) oxide 126 (visible in FIG. 12 ). According to a different embodiment, illustrated in FIGS. 14 and 15 , in a protective metal substrate 201 , for example brass, a cavity 205 is obtained by a molding process on a face 201 a. The protective substrate 201 ( FIG. 15 ) is coated with a metal layer 210 of copper, both on the face 201 a and on the walls of the cavity 205 , and then with a protective organometal layer 211 made of OSP material. A lid 209 is thus completed. As illustrated in FIG. 16 , the lid 209 is then bonded to a supporting substrate 213 , mounted on which are a MEMS acoustic transducer 215 , integrated in a first chip, and a control circuit 216 , integrated in a second chip. The supporting substrate 213 is moreover provided with a sound port 212 for the MEMS acoustic transducer 215 . A packaged microelectromechanical device 225 is thus formed, in particular a MEMS microphone, comprising the MEMS acoustic transducer 215 , the control circuit 216 , and a package 224 , forming part of which are the lid 209 and the supporting substrate 213 . To bond the lid 209 and the supporting substrate 213 , a layer of soldering paste is used around the MEMS acoustic transducer 215 and the control circuit 216 , which remain housed in the cavity 205 . In this step, the protective organometal layer 211 is thermally destroyed and exposes the metal layer 210 , enabling formation of a conductive soldering joint 220 . In addition, the atmosphere present in the cavity 205 causes oxidation of the copper in the exposed portions of the metal layer 210 , which are thus coated by a protective layer of copper (II) oxide 226 . FIG. 17 shows a simplified block diagram of a packaged microelectromechanical device 325 . The packaged microelectromechanical device 325 comprises a capacitive MEMS acoustic transducer 315 and an integrated control circuit 316 , housed in a package 324 according to any one of the embodiments described previously. The integrated control circuit 316 is configured to properly bias the MEMS acoustic transducer 315 , to process input signals S IN generated by capacitive variations of the MEMS acoustic transducer 315 , and to supply, on an output of the packaged microelectromechanical device 325 , a digital output signal S OUT , which can be then processed by a microcontroller of an associated electronic device. In one embodiment, the integrated control circuit 316 comprises: a pre-amplifier circuit 330 , of an analog type, which is configured to directly interface with the MEMS acoustic transducer 315 and to amplify and filter the input signal S IN supplied by the MEMS acoustic transducer 315 ; a charge pump 331 , which supplies appropriate voltages for biasing the MEMS acoustic transducer 315 ; an analog-to-digital converter 332 , for example of the sigma-delta type, configured to receive a clock signal CK and a differential signal amplified by the pre-amplifier circuit 330 and to convert the amplified differential signal into a digital signal; a reference generator 333 , connected to the analog-to-digital converter 332 and configured to supply a reference signal for the analog-to-digital converter 332 ; and a driving circuit 334 , configured to operate as interface with an external system, for example, a microcontroller of an associated electronic device. In addition, the packaged microelectromechanical device 325 may comprise a memory 335 of a volatile or non-volatile type, which may be, for example, programmed externally so as to enable a use of the packaged microelectromechanical device 325 in different operating configurations. The packaged microelectromechanical device 325 may be used in an electronic device 350 , as illustrated in FIG. 18 . The electronic device 350 is, for example, a portable mobile communication device (for example, a cell phone), a PDA (personal digital assistant), a portable computer (notebook), a voice recorder, a reader of audio files with capacity of voice recording, an acoustic apparatus, etc. The electronic device 350 comprises, in addition to the packaged microelectromechanical device 325 , a microprocessor 351 and an input/output interface 352 , connected to the microprocessor 351 and, for example, provided with a keyboard and a display. The packaged microelectromechanical device 325 communicates with the microprocessor 351 through a signal-processing module 353 . In addition, the electronic device 350 can comprise a loudspeaker 354 and an internal memory 355 . Modifications and variations may be made to the lid, to the packaged microelectromechanical device, and to the process described, without thereby departing from the scope of the present invention. In particular, the MEMS acoustic transducer could be replaced by a different MEMS sensor or transducer, in the case where there is the need for said devices to be packaged with a protective lid. The control device might not be present or might be incorporated in one and the same die with the MEMS device. The various embodiments described above can be combined to provide further embodiments. These and other changes can be made to the embodiments in light of the above-detailed description. In general, in the following claims, the terms used should not be construed to limit the claims to the specific embodiments disclosed in the specification and the claims, but should be construed to include all possible embodiments along with the full scope of equivalents to which such claims are entitled. Accordingly, the claims are not limited by the disclosure.

A process for manufacturing a packaged microelectromechanical device includes: forming a lid having a face and a cavity open on the face; coating the face of the lid and walls of the cavity with a metal layer containing copper; and coating the metal layer with a protective layer.

FIELD OF THE INVENTION This invention pertains to spray nozzles and more particularly to spray nozzles which produce an asymmetrical distribution of the fluid discharge. BACKGROUND OF THE INVENTION In order to protect substances such as food and beverages from contamination, a coating is typically applied to the inside surfaces of containers in which such substances are stored. This coating prevents the contents of the container from coming into direct contact with the bare metal or plastic interior surfaces of the container. With standard cylindrical containers or cans, this coating is generally applied to the interior of the container before the top is affixed through the use of a spray nozzle which is arranged to discharge through the open end of the container. As the coating is being discharged from the nozzle, the container is rotated about its longitudinal axis so as to ensure that all of the interior surfaces are coated. The coating material used on the inside surfaces of the containers represents one of the most significant costs associated with a container manufacturing operation. To help achieve an even coating, the coating material is generally applied using spray nozzles that are configured to produce an asymmetrical distribution of the fluid discharge. In particular, the nozzles generally produce a fan-shaped discharge pattern with a maximum amount of fluid being discharged at a point offset from the center of the spray pattern and with the level or amount of discharge tapering from the location of maximum discharge to either end of the spray pattern. These nozzles are arranged at an angle relative to the longitudinal axis of the container so that the heaviest portion of the discharge is directed towards the far, closed end of the container. Thus, the asymmetrical distribution helps compensate for the greater distance the coating material must travel to reach the closed end of the container and, in turn, the greater surface area of the interior of the container that this portion of the discharge pattern must cover. Because of the asymmetrical distribution of the fluid discharge, the spray nozzles must be arranged in a specific orientation relative to the containers to achieve the desired even coating of the interior of the containers. If the orientation of the spray nozzles is incorrect, the containers will not be properly coated. A container coating operation typically is highly automated. Thus, when one or more of the spray nozzles applying the coating is installed incorrectly, a significant amount of time may elapse before the problem is discovered. Because a container coating operation also runs at a very high speed, thousands of containers may be coated improperly during this time. Once the alignment problem with the spray nozzles is corrected, the defective containers then have to be collected and recoated. Obviously, this is an expensive and time consuming process. Currently, the standard practice for indicating the proper alignment of the spray nozzle is to place an arrow on the body of the nozzle. However, in a container coating operation, a build-up of the container coating material can quickly form on the spray nozzles. This build-up can obscure the arrow on the nozzle body making it difficult to determine if the nozzle is installed properly. BRIEF SUMMARY OF THE INVENTION A spray nozzle is provided which includes a nozzle body and a spray tip. The spray tip has a discharge orifice configured to produce a asymmetrically distributed fluid discharge pattern wherein the location of maximum fluid discharge is offset from the center of the fluid discharge pattern. The nozzle body includes an alignment notch extending in a longitudinal direction of the spray nozzle along an outer surface of the nozzle body. The alignment notch is arranged in a predetermined orientation relative to the discharge orifice. A spraying system is also provided including a spray gun and a spray nozzle. The spray gun has a discharge end. A locating pin is arranged on the discharge end of the spray gun. The spray nozzle is selectively mountable on the discharge end of the spray gun. The spray nozzle has a discharge orifice configured to produce a asymmetrically distributed fluid discharge pattern wherein the location of maximum fluid discharge is offset from the center of the fluid discharge pattern. The spray nozzle has an alignment notch extending along an outer surface of the spray nozzle. The locating pin is arranged on the spray gun and the alignment notch is arranged on the spray nozzle such that when the spray nozzle is mounted on the discharge end of the spray gun in a predetermined orientation the locating pin extends into the alignment slot. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic longitudinal section view of a container coating station incorporating an illustrative spray nozzle for producing an asymmetrical fluid discharge distribution pattern embodying the present invention. FIG. 2 is an enlarged perspective view of the illustrative asymmetric distribution spray nozzle of FIG. 1 showing the alignment notch. FIG. 3 is an exploded perspective view of the illustrative asymmetric distribution spray nozzle and an end of an illustrative spray gun having a complementary locating pin. FIG. 4 is a perspective view of the illustrative asymmetric distribution spray nozzle arranged on the end of the spray gun of FIG. 3 . FIG. 5 is a perspective view of the illustrative asymmetric distribution spray nozzle secured on the end of the spray gun by a retaining nut. FIG. 6 is a front view of the illustrative asymmetric distribution spray nozzle secured on the end of the spray gun by the retaining nut. FIG. 7 is a schematic drawing showing an exemplary asymmetric fluid discharge pattern for the illustrative spray nozzle for a container coating operation. DETAILED DESCRIPTION OF THE INVENTION Referring now more particularly to FIG. 1 , there is schematically shown, a portion of an exemplary container coating station that includes a spray nozzle 10 embodying the present invention which discharges, in this case, a coating material fluid in an asymmetrically distributed pattern. With the illustrated container coating station, open-ended containers 12 are indexed one-by-one to the coating station where the stationary spray nozzle 10 applies a coating material onto the interior surfaces of the container 12 through the open end 14 . The spray nozzle is attached to a spray gun 15 (not shown in FIG. 1 ) that, in turn, is connected to a supply of the coating material. The coating material may comprise vinyl, epoxy, acrylic or other suitable materials. As the coating material is being applied, the container 12 is rotated about its longitudinal axis 16 relative to the spray nozzle 10 at a relatively high speed (e.g., 500–3000 rpm) so that the coating material is applied to the entire interior of the container. As will be understood by those skilled in the art, while the spray nozzle of the present invention is described in connection with a container coating application, it may be employed in other applications and systems where an asymmetrical fluid discharge pattern is desired. To facilitate application of the coating material, the spray nozzle 10 is disposed on the longitudinal axis 16 of the container 12 a short distance from the open end 14 of the container as shown in FIG. 1 . Additionally, the spray nozzle 10 is canted such that the centerline 18 of the nozzle is disposed at an angle θ relative to the longitudinal axis 16 of the container, which, in this case, is oriented substantially horizontal. To compensate for the greater distance the coating material must travel to reach the closed end of the container 12 , the spray nozzle 10 is arranged so that the portion of the spray pattern with the heaviest discharge is directed generally towards the intersection of the bottom wall and cylindrical sidewall of the container. As will be appreciated by those skilled in the art, the angle θ of the spray nozzle 10 relative to the longitudinal axis 16 of the container can vary depending on the configuration of the container 12 being coated. In most instances, however, the spray nozzle 10 is preferably arranged at an angle θ of approximately 5° to 20° relative to the longitudinal axis 16 of the container. In the illustrated embodiment, the spray nozzle 10 includes a nozzle body 20 and a spray tip 22 having a dome shaped end wall 24 with a discharge orifice 26 formed therein, as best shown in FIGS. 2 and 6 . The discharge orifice 26 has an irregular shape that is configured to produce a spray pattern having the desired asymmetrical distribution of the fluid discharge. In this case, the discharge orifice 26 of the spray nozzle 10 is configured so as to produce a flat fan shaped pattern in which the heaviest discharge is shifted from the center towards one end of the fan pattern. One preferred distribution pattern for the spray nozzle 10 is schematically shown in FIG. 7 . In FIG. 7 , the amount of flow at different points in the spray pattern or fan is illustrated by the shaded areas in the troughs a–l. With this distribution pattern, the maximum amount of fluid is discharged at a point (trough i in the illustrated embodiment) approximately midway from the center and one end of the fan. From the point of maximum discharge, the amount of fluid discharged tapers in a non-linear manner to minimum discharge points at either end of the spray fan (trough a and trough l in FIG. 7 ). Additional details regarding how the discharge orifice can be configured to produce an improved fluid discharge pattern for container coating applications are provided in commonly owned U.S. Pat. No. 6,592,058 and U.S. patent application Ser. No. 09/967,417 the disclosures of which are incorporated herein by reference. As will be appreciated by those skilled in the art, the present invention is not limited to spray nozzles that produce any particular fluid discharge pattern. For example, instead of the non-linear taper shown in FIG. 7 , the discharge orifice 26 of the spray nozzle 10 could be configured to produce a discharge pattern in which the amount of discharge tapers linearly from the location of maximum discharge to either end of the spray pattern. The spray nozzle 10 could also be configured to produce a spray pattern in which the location of maximum discharge is located at or near one end of the spray pattern with the amount of discharge tapering to the other end of the discharge pattern. In the illustrated embodiment, the spray nozzle 10 can be attached to the spray gun 15 using a retaining member 28 , in this case a retaining nut. More specifically, as shown in FIG. 3 , the spray gun 15 includes a discharge end or tip 30 having a mounting surface 32 for receiving the spray nozzle 10 . As shown in FIG. 3 , the stem 34 of the end of the spray gun 15 is threaded so that when the spray nozzle 10 is arranged in position on the discharge end 30 of the spray gun 15 , the spray nozzle 10 can be secured in place via the retaining nut 28 (see FIGS. 4 and 5 ). In this case, the retaining nut 28 captures a flange 36 at the inlet end of the spray nozzle 10 so as to hold the spray nozzle on the spray gun 15 . In order to help ensure that the spray nozzle 10 is oriented properly with respect to the objects being sprayed, in this case the containers, the spray nozzle 10 has an alignment notch 38 arranged in a predetermined position relative to the discharge orifice 26 . The alignment notch 38 provides a visual indicator that an installer can use to ensure that the spray nozzle 10 is installed in the proper orientation on the spray guns. In particular, the alignment notch 38 can be positioned such that when the spray nozzle 10 is installed properly on a spray gun, the alignment notch faces a given direction. Moreover, the predetermined position of the alignment notch 38 relative to the discharge orifice 26 can be the same for a group of spray nozzles such that when installed properly the alignment notches of the group of nozzles all face the same direction. As will be appreciated, this makes it easy for an installer to install the spray nozzles very quickly and accurately. In the illustrated embodiment, the alignment notch 38 extends in a longitudinal direction along the outer surface of the side of the nozzle body 20 (see, e.g., FIGS. 2 and 4 ). The illustrated alignment notch 38 extends along a substantial portion of the length of the nozzle body 20 , in this case a majority (i.e., over one half) of the length, and cuts relatively deeply into the surface of the nozzle body. Thus, unlike an arrow, the alignment notch 38 provides a prominent structural feature that will not become obscured by a build-up of coating material on the spray nozzle 10 . To prevent the spray nozzle 10 from being installed out of alignment, the spray gun 15 can be equipped with a locating pin 40 that is received in the alignment notch 38 when the spray nozzle 10 is properly installed on the spray gun 15 . In the illustrated embodiment, the locating pin 40 extends outward from the mounting surface 32 on the discharge end 30 of the spray gun (see, e.g., FIGS. 3 and 4 ). Moreover, so as to be able to receive the locating pin 40 , the alignment notch 38 extends through the retaining flange 36 at the inlet end of the spray nozzle 10 . The locating pin 40 is arranged on the spray nozzle 10 in a predetermined position, for example relative to the objects being sprayed, such that when the nozzle is positioned on the discharge end 30 of the spray gun 15 in the proper orientation, the locating pin 40 extends into the alignment notch 38 as shown in FIGS. 4 and 6 . If the spray nozzle 10 is not oriented properly, the alignment notch 38 and the locating pin 40 will be misaligned and the installer will not be able to attach the spray nozzle 10 to the spray gun 15 . Thus, the locating pin 40 ensures that the spray nozzle 10 can only be installed in the proper orientation. From the foregoing, it can be seen that the asymmetric discharge spray nozzle of the present invention allows an installer to determine quickly and easily whether the nozzle is installed in the proper orientation relative to the objects being sprayed. This helps reduce or eliminate errors in the installation of such spray nozzles that can be costly and time consuming to correct. Moreover, if the asymmetric spray nozzle of the present invention is utilized with a spray gun having a locating pin according to another aspect of the present invention, the possibility of the spray nozzle being installed in the wrong orientation can be even further reduced if not eliminated. All references, including publications, patent applications, and patents, cited herein are hereby incorporated by reference to the same extent as if each reference were individually and specifically indicated to be incorporated by reference and were set forth in its entirety herein. The use of the terms “a” and “an” and “the” and similar referents in the context of describing the invention (especially in the context of the following claims) are to be construed to cover both the singular and the plural, unless otherwise indicated herein or clearly contradicted by context. The terms “comprising,” “having,” “including,” and “containing” are to be construed as open-ended terms (i.e., meaning “including, but not limited to,”) unless otherwise noted. Recitation of ranges of values herein are merely intended to serve as a shorthand method of referring individually to each separate value falling within the range, unless otherwise indicated herein, and each separate value is incorporated into the specification as if it were individually recited herein. All methods described herein can be performed in any suitable order unless otherwise indicated herein or otherwise clearly contradicted by context. The use of any and all examples, or exemplary language (e.g., “such as”) provided herein, is intended merely to better illuminate the invention and does not pose a limitation on the scope of the invention unless otherwise claimed. No language in the specification should be construed as indicating any non-claimed element as essential to the practice of the invention. Preferred embodiments of this invention are described herein, including the best mode known to the inventors for carrying out the invention. Variations of those preferred embodiments may become apparent to those of ordinary skill in the art upon reading the foregoing description. The inventors expect skilled artisans to employ such variations as appropriate, and the inventors intend for the invention to be practiced otherwise than as specifically described herein. Accordingly, this invention includes all modifications and equivalents of the subject matter recited in the claims appended hereto as permitted by applicable law. Moreover, any combination of the above-described elements in all possible variations thereof is encompassed by the invention unless otherwise indicated herein or otherwise clearly contradicted by context

A spraying system is provided including a spray gun and a spray nozzle. The spray gun has a discharge end. A locating pin is arranged on the discharge end of the spray gun. The spray nozzle is selectively mountable on the discharge end of the spray gun. The spray nozzle has a discharge orifice configured to produce a asymmetrically distributed fluid discharge pattern wherein the location of maximum fluid discharge is offset from the center of the fluid discharge pattern. The spray nozzle has an alignment notch extending along an outer surface of the spray nozzle. The locating pin is arranged on the spray gun and the alignment notch is arranged on the spray nozzle such that when the spray nozzle is mounted on the discharge end of the spray gun in a predetermined orientation the locating pin extends into the alignment slot.

BACKGROUND OF THE INVENTION I. Field of the Invention The present invention relates to a lighting control system for controlling the intensity of artificial illumination in order to automatically supplement natural illumination present in an area of concern. The total level of illumination is generally maintained constant, and the level of this constant illumination may be adjusted. II. Description of the Prior Art Fluorescent lighting fixtures and incandescent lighting fixtures are generally used for providing artificial illumination within modern office buildings. Architectural and economic limitations on the construction of new commercial buildings generally dictate that the office space include a suspended ceiling or false ceiling which includes suspended lighting fixtures, generally of the fluorescent type. The space between the suspended ceiling and the actual ceiling is generally reserved for ducting for air-conditioning and heating as well as electrical service for the lighting fixtures. The lighting fixtures are generally arranged in modular forms, with each of the illumination modules being independently controlled by a power switch. These power switches generally are of the on-off variety which merely remove power from the lights when the illuminated area is no longer in use by the occupants thereof. Continuously variable lighting controls are not frequently utilized by architects and building designers since they are aware that the occupants of the building will infrequently adjust the level of illumination, such as only once or twice per day in response to the sun being obscured by continuous layers of clouds, smog, fog, etc. The occupants of the office area generally will not devote the time and effort to continuously adjust the level of artificial illumination responsive to the sun being infrequently obscured for short periods of time by clouds, etc. Most modern office buildings have modular lighting systems in which one switch controls from between 1,000 to 1,600 watts of artificial illumination coupled to a 110 volt or 277 volt 60-cycle source of electrical power. Careful design and layout of the office area can define these illumination modules into areas which generally receive similar amounts of natural sunlight, such as through windows, skylights, etc. If areas receiving similar amounts of natural illumination are defined, then it may be possible to sense the level of natural illumination and use the artificial illumination only to supplement the natural illumination in order to maintain a relatively constant illumination over the area at all times. In this manner areas relatively close to outward facing windows may require little additional illumination, while areas substantially separated from outwardly facing windows may require nearly continuous illumination. Office areas having no exposure to natural illumination would of course not benefit from the presence of an automatic control circuit, since the control circuit would maintain a constant level of illumination. The present invention will be discussed assuming that modern lighting system techniques are utilized in the design of the typical office area. One example of these modern techniques are discussed in U.S. Pat. No. 4,001,571, issued to Martin. However, various other circuit branches or modular design techniques may be utilized without departing from the spirit and scope of the present system. Denger, in U.S. Pat. No. 3,458,770, discloses an automatic lighting control system for use with controlling the exposure of photosensitive paper. The system includes a bridge circuit having a photocell therein, with the output of the photocell being adjustable so as to interrupt the flow of electrical energy to an artificial source of illumination. The power is applied to the artificial source of illumination when the level of illumination falls below a single desired point, while power is interrupted when the level of illumination exceeds the predetermined level. An integrating circuit is utilized to equalize variations in illumination produced by the artificial source over an extended period of time. Dubot, in U.S. Pat. No. 3,961,183, discloses a photosensitive detector which is utilized in a simple voltage divider for sensing the relative level of illumination incident upon an area of interest. The non-bridged output of the photo-detector is coupled to the input of an analog circuit which in turn controls the supply of electrical energy to a single direction electrical motor. The motor sequentially closes switch contacts for coupling electrical energy to artificial illuminators. This system does not provide a tolerance interval over which the level of artificial illumination is acceptable, and apparently the motor can be driven only in a single direction. Fisher, in U.S. Pat. No. 2,920,247, discloses a circuit utilizing a tube-type multivibrator which is driven into oscillation by the incidence of light upon a photosensitive detector coupled to the grids thereof. As the multivibrator begins to oscillate, the output power from the multivibrator is utilized to control the passage of electrical energy through a control relay, such as the type which may be utilized to supply electrical energy to the headlights of an automobile. Long, in U.S. Pat. No. 2,078,677, discloses an artificial lighting display apparatus which is actuated when the level of natural light falls below a predetermined limit. As the device is actuated, the light sensor gradually illuminates and then gradually reduces the illumination from an artificial source of light of one color, and then periodically provides electrical energy to other colored sources of artificial illumination so as to artificially illuminate a subject area with periodically varying intensities of different colored lights. The intensity of the artificial illumination is controlled by placing resistance bars in series with the sources of illumination, thereby resulting in a very inefficient use of the electrical energy provided from the source. Krenke, in U.S. Pat. No. 3,210,611, discloses an electrooptical control circuit which is designed to control the flow of electrical energy to an artificial source of illumination responsive to the long-time averaging of the ambient or incident light as opposed to transient light changes. The time delay circuit eliminates changes in the flow of electrical energy to the source of artificial illumination responsive to rapid lighting fluctuations such as would be exhibited by the passage of a cloud in front of the sun. This electrical system does not provide for a dead zone or zone of acceptable lighting intensity, but instead automatically supplies electrical energy to the source of illumination if the ambient illumination falls below a predetermined limit for a selected period of time. Mas, in U.S. Pat. No. 3,180,978, discloses an illumination system which includes a wall-mounted window having a source of artificial illumination emanating from behind the normal ceiling-mounted illumination. An outside photosensor detects the intensity of external illumination and correspondingly adjusts the backlighting on the artificial window to produce similar lighting for the room, thereby simulating the normal variations in the intensities of natural lighting. The electrical control circuit may also be coupled to the overhead lights for supplying power thereto when the external natural illumination falls below a predetermined limit. This system controls internal illumination responsive to external illumination, but does not control the artificial illumination so as to supplement external natural illumination. Del Zotto, in U.S. Pat. No. 3,629,649, discloses a photodiode comprising one leg of a resistance bridge, with the intensity of illumination incident upon the photodiode controlling the operation of a latching relay which supplies electrical power to artificial sources of illumination. This system does not control the intensity of the artificial illumination, but merely turns the source of artificial illumination on and off. Crozier, in U.S. Pat. No. 3,878,439, discloses a photo-transistor which is coupled to a Schmidt trigger acting as a threshold detector for supplying electrical energy to a relay which in turn couples a load to a source of electrical energy. A timing circuit is provided for starting the operation of the relay when the phototransistor changes from an illuminated condition to a non-illuminated condition, or vice versa. Bolhuis, in U.S. Pat. No. 3,863,104, discloses a lighting control system for being utilized with at least two groups of electrically powered lamps, such as those utilized in transportation tunnels. Each of the groups of lamps is independently controlled, but not responsive to a level of ambient illumination. Charles, in U.S. Pat. No. 3,767,924, discloses an electrical make and break switch for use in controlling the lighting in a modern office building or school responsive to signals from a computer. Independent control of the lights is obtained through the computer and also from local stations by the utilization of photosensitive detectors at the local stations. McCabe, in U.S. Pat. No. 3,249,805, discloses a signal controlled rectifier (or silicon controlled rectifier-SCR) of the type which could be used for controlling the flow of electrical energy to a load. Reference is also made to a device in a pending United States patent application in the name of the National Aeronautics and Space Administration which includes a bidirectional mechanical motor which actuates serial switches for sequentially applying electrical energy to artificial sources of illumination. This device includes a plurality of mercury switches which are located about the circumference of a circular plate. The plate is rotated by the motor in steps responsive to the level of illumination incident upon a photocell. This patent application was filed on Dec. 23, 1976, and accorded the Ser. No. 753,977. These prior art references are illustrative of the many similar references located generally in the following classes/subclasses of U.S. Patent Office: 362/1, 20, 85, 147; 361/173, 174, 175, 197; 250/214 AL, 239; 307/116,117, 124,132 T, 311; 315/151, 153, 156, 158, 159, 149, 150, 152, 155, and others. The prior art also includes various existing designs which utilize a 555 timer having the inputs thereof shorted until the level of illumination crosses an unacceptable threshold limit. The inputs are then coupled to an R-C network having the appropriate time constant for determining the timing period. If at anytime during the timing period the level of illumination recrosses the illumination threshold, then the inputs of the clock timer are again shorted to ground. One limitation of this design appears when the voltage across the R-C network exceeds approximately 38 percent of the trigger voltage for the 555 device. Under these circumstances the noise impulse created by shorting the R-C network to ground generally will trigger the 555 device, thereby producing a false timing pulse which typically will produce a false change in the level of artificial illumination. In contrast with this design, the present invention utilizes a continuous clock and separate sampling gates which are periodically clocked to sample the levels of illumination and responsive thereto an error signal is generated. The use of a continuous clock with periodic sampling tends to eliminate the false triggering inherent in the aforementioned prior art designs. SUMMARY OF THE INVENTION The present invention relates to an illumination control system for controlling the flow of electrical energy from a source thereof to a plurality of lighting modules for supplementing the natural illumination within an interior space so as to maintain a desired level of illumination. The illumination control apparatus includes a plurality of power controllers each interposed between a source of electrical energy and one of the lighting modules. A photosensitive detector is provided for sensing the natural and artificial illumination within the interior space. An illumination limit detector is coupled to the photosensitive detector for generating a digital error signal responsive to the sensed illumination deviating outside of an acceptable illumination range defined between an upper illumination limit and a lower illumination limit. Upon receiving a clock signal the error signal is fed into a shift register. The shift register then actuates a corresponding one of the power controllers so as to adjust the total level of illumination within the interior space to fall within the acceptable range. In a first preferred embodiment, an impedance device is coupled across the error signal nodes of the bridge in order to provide mutual coupling therebetween. This coupling tends to reduce the sensitivity of the system during conditions of relatively intense illumination, while generally increasing the sensitivity of the system during lower levels of illumination. BRIEF DESCRIPTION OF THE DRAWINGS Other objects, features and advantages of the present invention will be apparent through a study of the written description and the drawings in which: FIG. 1 is a perspective illustration of an interior room having an automatic lighting control system in accordance with the present invention installed for regulating the artificial illumination so as to supplement the illumination provided by the natural sunlight. FIG. 2 illustrates a schematic diagram of bridge and control circuitry utilized in the first preferred embodiment of the present invention. FIG. 3 illustrates a schematic diagram of the logic and power control circuitry utilized in the first preferred embodiment of the present invention. FIG. 4 provides a truth or logic table for the various combinations of desired signal outputs from the bridge and control circuitry as illustrated in FIG. 2. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT A first preferred embodiment of an electronic automatic lighting control system in accordance with the teachings of the present invention is shown generally in FIG. 1. The system is designed to be employed in a room having external windows through which natural sunlight may pass. The purpose of this system is to automatically supplement the variable illumination from the sun with artificial illumination, such as from incandescent or fluorescent light sources. As illustrated in FIG. 1, a photosensitive detector, shown generally as 10, is mounted at a location within the interior section of the room so as to view a relatively wide angle section of the room. The photosensitive detector 10 will sense the combination of the natural sunlight passing through the windows and the artificial illumination from the fluorescent lights 11, 12, 13, 14, 15, 16, etc. A signal representative of the total level of both artificial and natural illumination present within the room will be transmitted through a circuit conductor 18 to bridge an error detecting logic circuitry 20, which is typically mounted adjacent to the door leading into the room within the junction box formerly provided for conventional on/off light control switches. The commands derived from the bridge and logic circuitry 20 are transmitted through the conductor 19 to an additional portion of the logic control system 20a which actuates, through conductor 19a, the appropriate power controllers 21, 22, 23, 24, 25, 26 and 27 which are typically mounted adjacent to corresponding ones of the fluorescent lighting modules 11, 12, 13, 14, 15, 16 and 17 for controlling the flow of electrical energy thereto. In this manner the error detecting and logic control systems 20 and 20a can activate or deactivate lighting modules so as to maintain a specified constant level of illumination within the interior space, regardless of any variation in or complete absence of natural illumination from the sun. A schematic diagram of a first preferred embodiment of the bridge and control circuitry of an automatic lighting control system in accordance the present invention is shown generally in FIG. 2. The photosensitive detector 10 is illustrated as being coupled by conductor 18 in series with a potentiometer 34 and a resistor 33 so as to form one leg 31 of a bridge circuit 30. A resistor 35 is coupled in series with a potentiometer 36 and another resistor 37 so as to form another leg 32 of the bridge circuit 30. The wiper arm of the potentiometer 34 forms the first node (V1) of the bridge 30, whereas the wiper arm of the potentiometer 36 forms the node (V2) in the second leg 32 of the bridge circuit 30. A third node of the bridge 30, defined by the coupling of the photosensitive detector 10 and the resistor 37, is coupled to ground potential. A fourth node defined at the intersection of the resistors 33 and 35 is coupled to a well regulated source of positive DC potential. In this manner the voltages at the signal node, designated as V1 for the first node and V2 for the second node, will vary in accordance with the changing impedance of the photosensitive detector 10. Typically this photosensitive detector 10 comprises a model CK505, such as produced by CLAIREX Manufacturing Co., of 560 So. 3rd Ave., Mt. Vernon, N.Y., but other photosensitive detectors with responses similar to the human eye may be substituted therefore. The photosensitive detector is generally characterized as a device which displays a reduced resistance responsive to an increase in the level of incident illumination. The photosensitive detector 10 should respond equally well to both natural light from the sun and to artificial light of the type produced by incandescent, daylight fluorescent, gas discharge, etc. lights. The first node, characterized by the wiper arm of the potentiometer 34, is coupled through an electrical conductor 44 in series with a resistor 43 to the first input 41 of a differential voltage comparator 40. A second input 42 of the voltage comparator 40 is coupled to the junction between a first resistor 45 and a second resistor 46, which are coupled across a voltage of known potential to form a voltage divider network for generating a first reference potential. In a like manner the second node, designated by the wiper arm of the potentiometer 36, is coupled through an electrical conductor 54 through a series resistor 53 to the first input 51 of a differential voltage comparator 50. A second input 52 of the differential comparator 50 is coupled to the center point of a voltage divider network comprising the resistors 55 and 56, which are coupled between a source of positive voltage potential and ground for generating a second reference potential. Throughout the following discussion the comparator 40 will be referenced as the first voltage comparator and will be assigned the function of an lower illumination limit detector, whereas the second comparator 50 will be assigned the function of a upper illumination limit detector. The resistors 45 and 46 are chosen so as to provide a lower level voltage reference at the second input 42 of the voltage comparator 40 so as to be generally equivalent to the lowest level of illumination which will bracket an acceptable range of illumination within the interior space of the room. Likewise, the resistors 55 and 56 are chosen so that the voltage input to the second input port 52 of the second voltage comparator 50 will represent the upper level or limit of the illumination in the acceptable illumination range. The value of the resistances 33 and 34, as well as the nominal resistance or impedance of the photosensitive detector 10, are chosen such that the voltage at the first node (V1), which is coupled through the isolation resistor 43 and into the first input 41 of the first voltage comparator 40, will equal the voltage input at the second port 42 of the comparator 40 at a level of illumination incident upon the photosensitive detector 10 which is exactly equal to the lower level of desired illumination within the acceptable range. As the intensity of the illumination incident upon the photosensitive detector 10 decreases, the voltage drop across the photosensitive detector 10 will increase thereby causing the voltage level at the first port 41 of the comparator 40 to rise above the lower level reference voltage at the second port 42 thereof, which will cause an output 49 of the comparator 40 to switch from a high voltage output to a low voltage output. Since the first input port 51 of the second voltage comparator 50 is coupled to the second node in the second leg 32 of the bridge circuit 30, one would expect that little if any voltage change would be apparent as a result of the impedance variations in the photosensitive detector 10 resulting from a change in the level of illumination thereon. However, a variable resistance, shown generally as 60, is coupled between a first node 34 and the second node 36 of the bridge circuit 30 so as to couple a portion of the voltage change across the photosensitive detector 10 into the first port 51 of the second voltage comparator 50. In this manner as the voltage across the photosensitive detector 10 decreases to a lower limit in the acceptable range, the voltage drop across the variable resistor 60 will also lower the voltage at the second node (V2), which in turn will reduce the voltage at the first port 51 of the second voltage comparator 50 until finally this voltage falls below the upper reference level voltage provided by the voltage divider comprising the resistances 55 and 56. At this time an output 59 of the second voltage comparator 50 will toggle from a low output to a high output. From the preceeding discussion it will be apparent after careful study that the rate of change of the voltage at the first node (V1) will generally be greater than the concommitant change in the voltage level at the second node (V2). However, the mutual coupling produced by the variable resistance 60 functionally reduces the rate of change of the voltage at the first node (V1) as compared with the rate of change of the voltage at the second node (V2). This mutual coupling is important in that it counteracts the undesirable logarithmic characteristics of the photosensitive detector 10. For example, if the median illumination intensity desired in a room is 50 foot candles and the allowable variance is plus/minus 10 foot candles (making the upper limit 60 foot candles and the lower limit 40 foot candles), then the photosensitive detector 10 will be operating in a relatively sensitive region of its input-output curve-that is a given change in light intensity will produce a relatively large change in output voltage. However, if the median illumination intensity desired in a room is 100 foot candles with an allowable variance of plus/minus 10 foot candles (making the upper limit 110 foot candles and the lower limit 90 foot candles), then the photosensitive detector 10 will be operating in a relatively insensitive region of its input-output curve-that is a given change in light intensity will produce a relatively small change in output voltage. Based upon these undesirable characteristics, the mutual coupling produced by resistor 60 will increase the apparent sensitivity (measured at the output of the bridge circuit) of the photosensitive detector 10 at the higher illumination levels, while the apparent sensitivity will be decreased at the lower illumination levels. Therefore, the allowable illumination intensity about the desired or median intensity may be more linear from higher to lower median illumination intensity. Another important function of the coupling resistor 60 may be described as follows. If the power controllers remove electrical energy from several lighting modules, then the level of artificial illumination and the total level of illumination will decrease. This decrease takes place in quantum steps which are dependent upon the total number of lighting modules and the relative number of these lighting modules which can be switched at one time. In cases involving relatively few lighting modules, the quantum decrease in illumination may cause the total level of illumination to decrease below the lower illumination limit unless the sensitivity of the system is decreased. Since the resistance 60 is variable, it may be adjusted by trained personnel so that the level of coupling between the first node and the second node will desensitize the gain of the system so that the minimum quantum decrease in illumination will not result in a total level of illumination falling below the lower illumination limit. If this coupling were not provided, then an oscillation could be established which would continuously turn on and then off again the lighting modules as the total level of illumination approximated the lower illumination limit. The adjustment of resistors 34 and 35 are relatively independent as long as resistance 60 is at its maximum resistance value. Thus, at any one illumination intensity level, the voltage at node (V1) will increase and decrease about a relatively fixed reference point as determined by resistance 34. Likewise, the voltage at node (V2) will remain generally fixed due to the minimum mutual coupling through resistance 60 and also due to the high ratios of the resistance values utilized in the bridge circuit 30. Conversely, when one or more of the lighting modules are illuminated, the feedback will not allow the voltage output of the comparators 40 and 50 to swing outside of the upper illumination limit, which would cause oscillatory operation of the detector. This threshold control, which utilizes both an upper and lower limit, provides a three state controller which has a range of adjustment from a maximum intensity, limited by the response of the photosensitive detector, down to a threshold illumination, which is just above the minimum intensity of response of the photosensitive detector. The photosensitive device has been selected to have the same photosensitive response characteristics as the human eye. While the particular device chosen has a logarithmic response, this response is compensated by bridge adjustment resistors 34 and 36 and also through the use of the feedback or mutual coupling resistor 60 within the bridge 30. With reference to FIGS. 2 and 3, the output 49 of the first comparator 40 is coupled through a circuit conductor 70 to a first input 83 of a first intermediate storage register 81. Likewise, the output of the second voltage comparator 50 is coupled from the output port 59 by a conductor 71 to a first input 84 of a second intermediate storage register 82. The digital values present at the outputs 49 and 59 of the first and second voltage comparators are loaded for storage into the intermediate storage registers 81 and 82 responsive to the positive edge of a clock signal generated by the clock generator 90 which is coupled through a circuit conductor 91 to second inputs 85 and 86 of the intermediate storage registers 81 and 82. The voltage levels at the outputs 87 and 88 respectively of the intermediate storage registers 81 and 82 will then be made to conform to the input levels at the instant of sampling. With continuing reference to FIGS. 2 and 3, the output 49 of the first voltage comparator 40 is also coupled through the conductor 70 to a first input 95 of a third intermediate storage register 96. The output 59 of the second voltage comparator 50 is also coupled through the circuit conductor 71 to a first input 94 of a fourth intermediate storage register 97. The clock inputs of both the third intermediate storage register 96 and the fourth intermediate storage register 97 are coupled through a circuit conductor 93 to the output of an inverter 92, which in turn is coupled through circuit conductor 91 to the output of the variable clock 90. The period of the variable clock 90 is adjustable for controlling the sampling period of the intermediate storage registers. Each time the output of the variable clock 90 goes positive, the first intermediate storage register 81 and the second intermediate storage register 82 are loaded with the values present at the inputs thereof. One-half cycle later on the negative edge of the output of the variable clock 90 the third intermediate storage register 96 and the fourth intermediate storage register 97 are loaded with the values present at the data inputs thereof. The system concept of time diversity sampling is important in the process of identifying abrupt changes in illumination which occur at relatively rapid intervals and for identifying changes in illumination which are not the result of actual changes in natural light levels, such as those produced by the inclination and/or declination of the sun. Instead, these changes are integrated over a time interval selected by the adjustable potentiometer 102 which varies the period of the output signal from the variable clock 90. The various outputs of the four intermediate storage registers 81, 82, 96 and 97 are coupled in appropriate logic sequence to various inputs of three Exclusive OR circuits (XOR) 106, 107 and 108. The operation of these XOR circuits may be most clearly illustrated by describing the desired outputs of the circuitry as a function of the inputs thereof. After a complete positive and negative clock period, the intermediate storage registers 81, 82, 96 and 97 will be loaded with a time diversity sample representative of the levels of illumination present upon the photosensitive detector 10. The truth table for the possible outputs of the two comparators is provided in FIG. 4. If the logic contents of the intermediate storage registers 81 and 96, and 82 and 97 are the same, then the XOR circuits 106 and 108 will produce a high level signal at the respective outputs 117 and 118 thereof. From this analysis it is apparent that for the outputs 117 and 118 of the XOR circuits 106 and 108 to be high, the logic contents of each of the horizontally equivalent intermediate storage register pairs 81 and 96 and 82 and 97 must be the same. The outputs 117 and 118 of the XOR circuits 106 and 108 will not both be high for any other combination. In a similar manner the XOR circuit 107 is connected to the outputs of the intermediate storage registers 96 and 97 in order to produce a high level signal at the output 119 thereof when the vertically related pairs of intermediate storage registers, that is 96 and 97 or 81 and 82, have the same logic levels stored therein. Since the logic contents of intermediate storage registers 96 and 97 should be the same as the logic contents of the intermediate registers 81 and 82 for normal operation of the circuitry, only the outputs of the intermediate storage registers 96 and 97 are sampled. Therefore, the output 110 of the XOR circuit 107 will be high only when the logic contents of the intermediate storage registers 96 and 97 are the same. The outputs 117, 110 and 118 respectively of the XOR circuits 106, 107 and 108 are coupled to the three inputs of the NAND circuit 109 which operates as a "NOT-AND" detector. The output 122 of the NAND circuit 109 is coupled to one input of a NOR (not OR) circuit 110. Another input 124 of the NOR circuit 110 is coupled through circuit conductor 91 to the output of the clock 90. The function of the NAND circuit 109 and the NOR circuit 110 will be explained as follows. If for any reason two consecutive half-cycle periods of the output of the variable clock 90 elapse in which all four intermediate storage registers 81, 82, 96 and 97 are equal, then the output 122 of the NAND circuit 109 will go low. This level transition occurs because the outputs 117, 119 and 118 respectively from the XOR circuits 106, 107 and 108 will all be high. On the other hand, if the outputs 117, 119 and 118 are in any other logic conditions other than the one previously mentioned, the output 122 of the NAND circuit 109 will go high. If the NOR circuit 127 has a low level signal at input 123, and if the input 124 includes a low level signal from the clock generator, then the output 125 of the NOR circuit 127 will go high. The output 125 of the NOR circuit 127 is coupled to the clock input of the shift register 126, and to other shift registers which also may be coupled thereto. The number of shift registers 126 will be determined by the number of outputs and the total number of lighting modules to be controlled. For the sake of clarity only one shift register 126 is illustrated in FIG. 3, and also for the sake of clarity the shift register 126 is illustrated as having only four outputs, of which only one is illustrated as being utilized. However, one skilled in the art will recognize that other shift registers and outputs may be connected in the same manner for the proper operation of this system. Shift control ports 130 and 132 of the shift register 126 are coupled through the circuit conductors 128 and 131 respectively to the outputs 98 and 100 respectively of the intermediate storage registers 96 and 97. The logic levels apparent at the data inputs 130 and 132 of the shift register 126, upon the occurence of a clock pulse at the clock input thereof, will cause the activation or deactivation of the next sequential output of the shift register 126. The operation of such shift registers are well known in the art and will not be described in detail herein. The various outputs 141, 142, 143 and 144 are coupled through corresponding circuit conductors to the input ports of power controllers 151, 152, etc. These power controllers are typically triac or SCR type devices. The power controller 131 is interposed in series between a source of electrical power, such as 60 Hz 110 VOLT AC commercial power, and the lighting module 161 controlled thereby. The power controllers 151, etc. typically function as electronic on-off switches for interrupting the flow of electrical power to the corresponding lighting modules 161, etc. As previously explained each of the lighting modules is arranged about the interior space of the room to be illuminated so as to be interspersed among each other and strategically located in the areas of the room which generally require the most frequent addition of artificial illumination for supplementing the natural solar illumination thereon. As plus or minus error signals or data signals are clocked into the shift register 126, the appropriate change in one or more of the outputs 141, etc. will be made so as to increment the number of illuminated lighting modules by the corresponding amount and in the proper direction. For example, if the input error signal clocked into the input ports 130 and 132 of the shift register 126 signify that one additional lighting module should be energized, the output 141, etc. representing the next significant bit in the shift register 126 will be energized and will transmit a signal over the appropriate conductor to energize the appropriate power controller 151, etc. As the power controller 151 is energized, electrical energy from the source thereof will be coupled to the lighting module 161 by turning on TRIAC 170 so as to provide an increased level of illumination. The first preferred embodiment of the automatic lighting control system has been specifically designed in order to permit simple and economic installation for automatic control of lighting systems with existing power wiring. While other preferred embodiments may be designed for initial installation of new lighting systems, it is presently envisioned that the first preferred embodiment of the present invention is suitable for both new and existing lighting system. The installation of the automatic lighting control system will be described with specific reference to FIG. 1. First the photosensitive detector 10 is installed in a position within the enclosed room so as to receive a typical level of natural as well as artificial illumination characteristic of the average levels of illumination throughout the room. Typically the position of the photosensitive detector would be at a point spaced from the windows of the room and also spaced from the recessed areas of the room which require constant artificial illumination. The control leads 18 from the photosensitive detector 10 are then routed to the power control box, shown generally as 20. The power control switches from the control box are then removed and the bridge circuit 30 and voltage comparators 40 and 50, together with their associated circuitry, are then installed in the power control box 20. In this manner the various adjustment potentiometers 34, 36 and 60 as well as the resistance values in the latter networks 45 and 46 as well as 55 and 56 will be available for adjustment and interchanging of parts by a skilled technician. Also, various systems of control level indicators may be mounted at the power control box 20 in order to provide a visual indication as to the relative lighting conditions within the room as compared with the upper and lower illumination levels defining the acceptable bracket of illumination within the enclosed area. The conductors 70 and 71, coupled respectively to the outputs 49 and 59 of the voltage comparators 40 and 50, typically are connected during installation to the already existing cable conductors in the conduit 19 which were previously used to couple the lighting fixtures through the on/off switch to the main source of electrical energy. Since the source of electrical energy will be coupled directly to each of the logic subsystems, 21, 22, 23, 24, etc., which also include the corresponding power controllers 151, etc., the circuit conductors in the conduit 19 and 19a may be disconnected and used independently of the AC power source. Therefore, the appropriate power controllers may be connected directly to the appropriate artificial illumination modules, 11, 12, etc. In the first preferred embodiment of the present invention the power controllers 21 etc. are designed to be physically attached to or adjacent to the appropriate lighting module for electrical ground continuity. Each of the power controllers may be utilized to control an entire functional group of lights, or in the alternative, multiple power controllers may be provided to control individual sources of illumination within one lighting fixture. Installation time and expenses are minimized by utilizing existing wiring and to locate the power control circuitry immediately adjacent the lighting module to be controlled. In this manner the requirement of additional wiring and the associate labor are minimized. As illustrated in FIG. 1, the low level logic signals may be coupled between or among the various logic subsystems and power controllers through the use of low cost, low gauge wiring as opposed to the use of high cost, high voltage wiring which not only is heavy but also is difficult to handle. The present system may be utilized to control the levels of artificial illumination in existing 110 Volt 60 Hz residential wiring system. Other embodiments of the present invention may be adapted to control higher voltage lighting systems, such as 200 to 240 Volt AC industrial of foreign systems. The utilization of a switch controller circuit breaker at the power distribution box is optional, since the main power controller can be installed or interposed at any convenient position along the main electrical conductor. Of course, the photosensitive detector, bridge circuitry and logic circuitry may be spaced from the power controllers at any conveniently accessible location. The first preferred embodiment of the present invention may also be easily adapted for use with control wires already existing within 28 Volt AC lighting systems which utilize the 28 Volt signal to actuate relays or circuit breakers remotely located in the main power line. The use of the solid state power controllers as disclosed in the present invention would eliminate many of the costly relays and their typical reliability problems which are common in these 28 Volt control systems. It is also envisioned that appropriate signals may be coupled to the disable inputs of the shift register, typically 126, in order to allow a central computer to be utilized for disabling the entire artificial lighting control system following the interruption of power thereto. In this manner, the load representing the artificial illumination system (approximately 60 percent of the load of a typical office environment) may be decoupled from the source of electrical energy so that the very large surge currents drawn by electrical motors and other induction type machinery may be accommodated during startup. The lighting control system will be enabled after a short delay period following the reavailability of electrical energy. After the automatic lighting control system has been installed, the proper value of the ladder resistors 45 and 46 as well as 55 and 56 are selected and installed for determining the upper and lower illumination limits which define or bracket the interval of acceptable illumination within the enclosed area. After the appropriate photosensitive detector 10 has been chosen and installed, the adjustable resistors 34 and 36 are balanced so as to provide a balanced output signal therefrom. Next, the mutual coupling between the first node and the second node of the bridge 30 is adjusted by varying the resistance present through potentiometer 60. The value of mutual coupling across the primary nodes of the bridge 30 is adjusted so as to: (1) limit the rate of change of the voltage at the first node V1 with respect to the voltage at the second node V2; and (2) adjust the effective operational sensitivity of the two voltage comparators 40 and 50 to correct the changes in non-linear operation of the photosensitive detector 10 in the levels of illumination near the lower level of illumination as compared with the sensitivity near the upper level of illumination. Next, the variable resistor 102 is adjusted to designate the desired period of the clock signal from the variable clock 90. The period of the clock signal may be varied between several seconds at a minimum up to 90 minutes or more at a maximum. This period of the clock signal is adjusted to prevent the normal short variations in the level of natural illumination from triggering changes within the system. These short changes in natural illumination may be caused by the passage of clouds between the sun and the building, the presence of automobile reflections, other sources of artificial illumination within the building, and pedestrian traffic in areas adjacent to the photosensitive detector 10. Thus, a first preferred embodiment of the automatic lighting control system in accordance with the present invention has been illustrated as an example of the invention as claimed. However, the present invention should not be limited in its application to the details illustrated in the accompanying drawings of the specification, since this invention may be practiced and constructed in a variety of different embodiments. Also, it must be understood that the terminology and descriptions employed herein are used solely for the purpose of describing the general operation of the preferred embodiments and therefore should not be construed as limitations on the operability of the invention.

This invention relates to an automatic lighting control system which employs a photosensitive detector in one leg of a bridge circuit for sensing the total effective level of both the natural and artificial illumination within an interior space. The unbalanced output of the bridge is fed into a pair of differential comparators for deriving a digital error signal representative of the level of illumination falling outside an acceptable range. A digital error signal is loaded into an intermediate shift register responsive to a clock signal. If an error signal of the type requiring a change in illumination is present, then a subsequent clock pulse will command a shift register to add or interrupt power to one or more lighting modules which supply artificial illumination to the interior space.

This application is a divisional application of U.S. Ser. No. 13/295,470 filed on Nov. 14, 2011, which is a divisional application of U.S. Ser. No. 12/094,296 filed on Sep. 2, 2008, now U.S. Pat. No. 8,084,488, which is a 371 application of PCT/1B2006/003239 filed on Nov. 9, 2006, which claims benefit of provisional application U.S. Ser. No. 60/738,447 filed on Nov. 21, 2005, all of which are incorporated herein by reference in their entirety. FIELD OF THE INVENTION The present invention relates to Novel forms of [R—(R*,R*)]−2-(4-fluorophenyl)-β,δ-dihydroxy-5-(1-methylethyl)-3-phenyl-4-[(phenylamino)carbonyl]−1H-pyrrole-1-heptanoic acid magnesium salt designated Form A, Form B, Form C, Form D, Form E, and Form F, characterized by one or more of their X-ray powder diffraction, solid state NMR carbon chemical shift, and solid state NMR fluorine chemical shift. The present invention also relates to pharmaceutical compositions containing such compounds, methods for their preparation and methods for their use in the treatment of hyperlipidemia, hypercholesterolemia, osteoporosis, benign prostatic hyperplasia (BPH) and Alzheimer's disease. BACKGROUND OF THE INVENTION The conversion of 3-hydroxy-3-methylglutaryl-coenzyme A (HMG-CoA) to mevalonate is an early and rate-limiting step in the cholesterol biosynthetic pathway. This step is catalyzed by the enzyme HMG-CoA reductase. Statins inhibit HMG-CoA reductase from catalyzing this conversion. As such, statins are collectively potent lipid lowering agents. Atorvastatin calcium, disclosed in U.S. Pat. No. 5,273,995, which is incorporated herein by reference, is currently sold as LIPITOR® having the chemical name [R—(R*,R*)]−2-(4-fluorophenyl)-β,δ-dihydroxy-5-(1-methylethyl)-3-phenyl-4-[(phenylamino)carbonyl]−1H-pyrrole-1-heptanoic acid calcium salt (2:1) trihydrate. Atorvastatin calcium is a selective, competitive inhibitor of HMG-CoA reductase. As such, atorvastatin calcium is a potent lipid lowering compound and is thus useful as a hypolipidemic and/or hypocholesterolemic agent. A number of patents have issued disclosing atorvastatin, formulations of atorvastatin, as well as processes and key intermediates for preparing atorvastatin. These include: U.S. Pat. Nos. 4,681,893; 5,273,995; 5,003,080; 5,097,045; 5,103,024; 5,124,482; 5,149,837; 5,155,251; 5,216,174; 5,245,047; 5,248,793; 5,280,126; 5,397,792; 5,342,952; 5,298,627; 5,446,054; 5,470,981; 5,489,690; 5,489,691; 5,510,488; 5,686,104; 5,998,633; 6,087,511; 6,126,971; 6,433,213; and 6,476,235, which are herein incorporated by reference. Additionally, a number of published International Patent Applications and patents have disclosed crystalline forms of atorvastatin, as well as processes for preparing amorphous atorvastatin. These include: U.S. Pat. No. 5,969,156; U.S. Pat. No. 6,121,461;U.S. Pat. No. 6,605,729; WO 00/71116; WO 01/28999; WO 01/36384; WO 01/42209; WO 02/41834; WO 02/43667; WO 02/43732; WO 02/051804; WO 02/057228; WO 02/057229; WO 02/057274; WO 02/059087; WO 02/072073; WO 02/083637; WO 02/083638; WO 03/050085; WO 03/070702; and WO 04/022053. Atorvastatin is prepared as its calcium salt, i.e., [R—(R*,R*)]−2-(4-fluorophenyl)-β,δ-dihydroxy-5-(1-methylethyl)-3-phenyl-4-[(phenylamino)-carbonyl]−1H-pyrrole-1-heptanoic acid calcium salt (2:1). The calcium salt is desirable, since it enables atorvastatin to be conveniently formulated in, for example, tablets, capsules, lozenges, powders, and the like for oral administration. The process by which atorvastatin calcium is produced needs to be one which is amenable to large-scale production. Additionally, it is desirable that the product should be in a form that is readily filterable and easily dried. Finally, it is economically desirable that the product be stable for extended periods of time without the need for specialized storage conditions. Furthermore, it has been disclosed that the amorphous forms in a number of drugs exhibit different dissolution characteristics, and in some cases different bioavailability patterns compared to the crystalline forms (Konno T., Chem. Pharm. Bull., 1990; 38; 2003-2007). For some therapeutic indications, one bioavailability pattern may be favored over another. In the course of drug development, it is generally assumed to be important to discover the most stable crystalline form of the drug. This most stable crystalline form is the form which is likely to have the best chemical stability, and thus the longest shelf-life in a formulation. However, it is also advantageous to have multiple forms of a drug, e.g. salts, hydrates, polymorphs, crystalline, and noncrystalline forms. There is no one ideal physical form of a drug because different physical forms provide different advantages. The search for the most stable form and for such other forms is arduous and the outcome is unpredictable. The successful development of a drug requires that it meet certain requirements to be a therapeutically effective treatment for patients. These requirements fall into two categories: (1) requirements for successful manufacture of dosage forms, and (2) requirements for successful drug delivery and disposition after the drug formulation has been administered to the patient. There are many kinds of drug formulations for administration by various routes, and the optimum drug form for different formulations is likely to be different. As mentioned above, a drug formulation must have sufficient shelf-life to allow successful distribution to patients in need of treatment. In addition, a drug formulation must provide the drug in a form which will dissolve in the patient's gastrointestinal tract when orally dosed. For oral dosing in an immediate release dosage form, such as an immediate release tablet, capsule, suspension, or sachet, it is generally desirable to have a drug salt or drug form which has high solubility, in order to assure complete dissolution of the dose and optimal bioavailability. For some drugs, particularly low solubility drugs or poorly wetting drugs, it may be advantageous to utilize a noncrystalline drug form, which will generally have a higher initial solubility than a crystalline form when administered into the gastrointestinal tract. A noncrystalline form of a drug is frequently less chemically stable than a crystalline form. Thus, it is advantageous to identify noncrystalline drug forms which are sufficiently chemically stable to provide a practical product which is stable enough to maintain its potency for enough time to permit dosage form manufacture, packaging, storage, and distribution to patients around the world. On the other hand, there are dosage forms which operate better if the drug form is less soluble. For example, a chewable tablet or a suspension or a sachet dosage form exposes the tongue to the drug directly. For such dosage forms, it is desirable to minimize the solubility of the drug in the mouth, in order to keep a portion of the drug in the solid state, minimizing bad taste. For such dosage forms, it is often desirable to use a low solubility salt or crystalline form. For controlled release oral or injectable, e.g. subcutaneous or intramuscular, dosage forms, the desired drug solubility is a complex function of delivery route, dose, dosage form design, and desired duration of release. For a drug which has high solubility, it may be desirable to utilize a lower solubility crystalline salt or polymorph for a controlled release dosage form, to aid in achievement of slow release through slow dissolution. For a drug which has low solubility, it may be necessary to utilize a higher solubility crystalline salt or polymorph, or a noncrystalline form, in order to achieve a sufficient dissolution rate to support the desired drug release rate from the controlled release dosage form. In soft gelatin capsule dosage forms (“soft-gels”), the drug is dissolved in a small quantity of a solvent or vehicle such as a triglyceride oil or polyethylene glycol, and encapsulated in a gelatin capsule. An optimal drug form for this dosage form is one which has a high solubility in an appropriate soft-gel vehicle. In general, a drug form which is more soluble in a triglyceride oil will be less soluble in water. Identification of an appropriate drug form for a soft-gel dosage form requires study of various salts, polymorphs, crystalline, and noncrystalline forms. Thus, it can be seen that the desired solubility of a drug form depends on the intended use, and not all drug forms are equivalent. For a drug form to be practically useful for human or animal therapy, it is desirable that the drug form exhibit minimal hygroscopicity. Dosage forms containing highly hygroscopic drugs require protective packaging, and may exhibit altered dissolution if stored in a humid environment. Thus, it is desirable to identify nonhygroscopic crystalline salts and polymorphs of a drug. If a drug is noncrystalline, or if a noncrystalline form is desired to improve solubility and dissolution rate, then it is desirable to identify a noncrystalline salt or form which has a low hygroscopicity relative to other noncrystalline salts or forms. A drug, crystalline or noncrystalline, may exist in an anhydrous form, or as a hydrate or solvate or hydrate/solvate. The hydration state and solvation state of a drug affects its solubility and dissolution behavior. The melting point of a drug may vary for different salts, polymorphs, crystalline, and noncrystalline forms. In order to permit manufacture of tablets on commercial tablet presses, it is desirable that the drug melting point be greater than around 60° C., preferably greater than 100° C. to prevent drug melting during tablet manufacture. A preferred drug form in this instance is one that has the highest melting point. In addition, it is desirable to have a high melting point to assure chemical stability of a solid drug in a solid dosage form at high environmental storage temperatures which occur in direct sunlight and in geographic areas such as near the equator. If a soft-gel dosage form is desired, it is preferred to have a drug form which has a low melting point, to minimize crystallization of the drug in the dosage form. Thus, it can be seen that the desired melting point of a drug form depends on the intended use, and not all drug forms are equivalent. When a drug's dose is high, or if a small dosage form is desired, the selection of a salt, hydrate, or solvate affects the potency per unit weight. For example, a drug salt with a higher molecular weight counterion will have a lower drug potency per gram than will a drug salt with a lower molecular weight counterion. It is desirable to choose a drug form which has the highest potency per unit weight. The method of preparation of different crystalline polymorphs and noncrystalline forms varies widely from drug to drug. It is desirable that minimally toxic solvents be used in these methods, particularly for the last synthetic step, and particularly if the drug has a tendency to exist as a solvate with the solvent utilized in the last step of synthesis. Preferred drug forms are those which utilize less toxic solvents in their synthesis. The ability of a drug to form good tablets at commercial scale depends upon a variety of drug physical properties, such as the Tableting Indices described in Hiestand H, Smith D. Indices of tableting performance. Powder Technology, 1984; 38:145-159. These indices may be used to identify forms of a drug, e.g. of atorvastatin calcium, which have superior tableting performance. One such index is the Brittle Fracture Index (BFI), which reflects brittleness, and ranges from 0 (good-low brittleness) to 1 (poor-high brittleness). Other useful indices or measures of mechanical properties, flow properties, and tableting performance include compression stress, absolute density, solid fraction, dynamic indentation hardness, ductility, elastic modulus, reduced elastic modulus, quasistatic indentation hardness, shear modulus, tensile strength, compromised tensile strength, best case bonding index, worst case bonding index, brittle/viscoelastic bonding index, strain index, viscoelastic number, effective angle of internal friction (from a shear cell test), cohesivity (from a powder avalanche test), and flow variability. A number of these measures are obtained on drug compacts, preferably prepared using a triaxial hydraulic press. Many of these measures are further described in Hancock B, Carlson G, Ladipo D, Langdon B, and Mullarney M. Comparison of the Mechanical Properties of the Crystalline and Amorphous Forms of a Drug Substance. International Journal of Pharmaceutics, 2002; 241:73-85. Drug form properties which affect flow are important not just for tablet dosage form manufacture, but also for manufacture of capsules, suspensions, and sachets. The particle size distribution of a drug powder can also have large effects on manufacturing processes, particularly through effects on powder flow. Different drug forms have different characteristic particle size distributions. From the above discussion, it is apparent that there is no one drug form which is ideal for all therapeutic applications. Thus it is important to seek a variety of unique drug forms, e.g. salts, polymorphs, noncrystalline forms, which may be used in various formulations. The selection of a drug form for a specific formulation or therapeutic application requires consideration of a variety of properties, as described above, and the best form for a particular application may be one which has one specific important good property while other properties may be acceptable or marginally acceptable. The present invention answers the need by providing novel forms of atorvastatin magnesium. Thus the present invention provides new forms of atorvastatin magnesium designated Forms A, B, C, D, E, and F. The new forms of atorvastatin magnesium disclosed in the present application offer the advantage of high water solubility. This is an advantage for immediate release dosage forms since such forms need to be fully dissolved in the stomach before passing into the digestive tract. SUMMARY OF THE INVENTION In a first aspect, the present invention comprises a Form A atorvastatin magnesium having one or more of characteristics selected from the group consisting of: I) an X-ray powder diffraction containing the following 2θ values measured using CuK a radiation: 9.3, 14.3, and 18.4; II) a 13 C shift containing the values: 118.7, 124.4, 140.3, and 141.7 ppm; and III) an 19 F shift containing the values: −108.4, and −112.6 ppm. As described herein, the x-ray powder diffraction (XRPD) pattern is expressed in terms of degree 2θ and relative intensities with a relative intensity of >10% and relative peak width measured on a Bruker D8 Discover X-ray powder diffractometer with GADDS (General Area Diffraction Detector System) CS (available from Bruker AXS, Inc., 5465 East Cheryl Parkway, Madison, Wis.) operating in reflection mode using CuK a radiation (1.54 Å). Furthermore, in each aspect, the invention encompasses experimental deviation in the 2θ and the shift values described herein; including the deviation ±0.2° 2θ as provided in X-ray powder diffraction (XPRD) Tables 1-7, and deviation ±0.2 ppm as provided in solid state nuclear magnetic resonance (SSNMR) Tables 8-19 below. Based on the descriptions set forth herein, such experimental deviation in the 2θ and the shift values can be readily determined by the ordinarily skilled artisan. In one embodiment, the Form A atorvastatin magnesium of the invention has an X-ray powder diffraction containing the following 2θ values measured using CuK a radiation: 9.3, 11.7, 14.3, and 18.4 In another embodiment, the Form A atorvastatin magnesium of the invention has an X-ray powder diffraction containing the 2θ values measured using CuK a radiation as set forth in Table 1 and Table 7 below. In another embodiment, the Form A atorvastatin magnesium of the invention has a solid state NMR shift selected from the group consisting of: A) a 13 C shift containing the values: 118.7, 124.4, 140.3, and 141.7 ppm; and B) an 19 F shift containing the values: −108.4, and −112.6 ppm. In another embodiment, the Form A atorvastatin magnesium of the invention has a 13 C shift containing the values: 118.7, 124.4, 140.3, and 141.7 ppm. In another embodiment, the Form A atorvastatin magnesium of the invention has a 13 C shift containing the values set forth in Table 8. In another embodiment, the Form A atorvastatin magnesium of the invention has a an 19 F shift containing the values: −108.4, and −112.6 ppm. In another embodiment, the Form A atorvastatin magnesium of the invention has an X-ray powder diffraction containing the following 2θ values measured using CuK a radiation: 9.3, 14.3, and 18.4; a 13 C shift containing the values: 118.7, 124.4, 140.3, and 141.7 ppm; and an 19 F shift containing the values: −108.4, and −112.6 ppm. In a second aspect, the present invention is directed to Form B atorvastatin magnesium characterized by x-ray powder diffraction (XRPD) pattern expressed in terms of degree 2θ and relative intensities with a relative intensity of >10% and relative peak width measured on a Bruker D8 Discover X-ray powder diffractometer with GADDS (General Area Diffraction Detector System) CS operating in reflection mode using CuK a radiation (1.54 Å) as set forth in Table 2 and Table 7 below. In a third aspect, the present invention is directed to Form C atorvastatin magnesium characterized by x-ray powder diffraction (XRPD) pattern expressed in terms of degree 2θ and relative intensities with a relative intensity of >10% and relative peak width measured on a Bruker D8 Discover X-ray powder diffractometer with GADDS (General Area Diffraction Detector System) CS operating in reflection mode using CuK a radiation (1.54 Å) as set forth in Table 3 and Table 7 below. In a fourth aspect, the present invention is directed to Form D atorvastatin magnesium characterized by x-ray powder diffraction (XRPD) pattern expressed in terms of degree 2θ and relative intensities with a relative intensity of >10% and relative peak width measured on a Bruker D8 Discover X-ray powder diffractometer with GADDS (General Area Diffraction Detector System) CS operating in reflection mode using CuK a radiation (1.54 Å) as set forth in Table 4 and Table 7 below. In a fifth aspect, the present invention is directed to Form E atorvastatin magnesium characterized by x-ray powder diffraction (XRPD) pattern expressed in terms of degree 2θ and relative intensities with a relative intensity of >10% and relative peak width measured on a Bruker D8 Discover X-ray powder diffractometer with GADDS (General Area Diffraction Detector System) CS operating in reflection mode using CuK a radiation (1.54 Å) as set forth in Table 5 and Table 7 below. In a sixth aspect, the present invention is directed to Form F atorvastatin magnesium characterized by x-ray powder diffraction (XRPD) pattern expressed in terms of degree 2θ and relative intensities with a relative intensity of >10% and relative peak width measured on a Bruker D8 Discover X-ray powder diffractometer with GADDS (General Area Diffraction Detector System) CS operating in reflection mode using CuK a radiation (1.54 Å) as set forth in Table 6 and Table 7 below. A further embodiment of the invention is a pharmaceutical composition comprising Form A, B, C, D, E, or F of atorvastatin magnesium in admixture with at least one pharmaceutically acceptable excipient, diluent, or carrier, each as described herein. The atorvastatin magnesium Forms A, B, C, D, E and F disclosed herein may be used in the treatments and regimens and at the dosage ranges for which atorvastatin calcium (LIPITOR®) is known in the art to be useful. As inhibitors of HMG-CoA reductase, Forms A, B, C, D, E, and F of atorvastatin magnesium are useful as hypolipidemic and hypocholesterolemic agents as well as agents in the treatment of osteoporosis, benign prostatic hyperplasia (BPH), and Alzheimer's disease. Accordingly, a still further embodiment of the present invention is a method of treating hyperlipidemia, hypercholesterolemia, osteoporsis, benign prostatic hyperplasia (BPH), and Alzheimer's disease comprising the step of administering to a patient suffering therefrom a therapeutically effective amount of Form A, Form B, Form C, Form D, Form E, or Form F atorvastatin magnesium, each as described herein, in unit dosage form. The invention further provides for the use of Form A, Form B, Form C, Form D, Form E, or Form F atorvastatin magnesium, each as described herein, in the preparation of a medicament for the treatment of hyperlipidemia, hypercholesterolemia, osteoporosis, benign prostatic hyperplasia, or Alzheimer's disease. Also, the invention provides for the use of Form A, Form B, Form C, Form D, Form E, or Form F atorvastatin magnesium, or a combination of two or more of these forms, each as described herein, in the treatment of hyperlipidemia, hypercholesterolemia, osteoporosis, benign prostatic hyperplasia, or Alzheimer's disease. Finally, the present invention is directed to methods for production of Form A, Form B, Form C, Form D, Form E, or Form F atorvastatin magnesium, each as described herein. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 : Diffractogram of Form A atorvastatin magnesium measured on a Bruker D8 DISCOVER with GADDS (General Area Diffraction Detector System) CS X-ray powder diffractometer. FIG. 2 : Diffractogram of Form B atorvastatin magnesium measured on a Bruker D8 DISCOVER with GADDS CS X-ray powder diffractometer. FIG. 3 : Diffractogram of Form C atorvastatin magnesium measured on a Bruker D8 DISCOVER with GADDS CS X-ray powder diffractometer. FIG. 4 : Diffractogram of Form D atorvastatin magnesium measured on a Bruker D8 DISCOVER with GADDS CS X-ray powder diffractometer. FIG. 5 : Diffractogram of Form E atorvastatin magnesium measured on a Bruker D8 DISCOVER with GADDS CS X-ray powder diffractometer. FIG. 6 : Diffractogram of Form F atorvastatin magnesium measured on a Bruker D8 DISCOVER with GADDS CS X-ray powder diffractometer. FIG. 7 : Proton decoupled 13 C CPMAS spectra of Form A atorvastatin magnesium. The peaks marked with an asterisk are spinning sidebands. FIG. 8 : Proton decoupled 13 C CPMAS spectra of Form B atorvastatin magnesium. The peaks marked with an asterisk are spinning sidebands. FIG. 9 : Proton decoupled 13 C CPMAS spectra of Form C atorvastatin magnesium. The peaks marked with an asterisk are spinning sidebands. FIG. 10 : Proton decoupled 13 C CPMAS spectra of Form D atorvastatin magnesium. The peaks marked with an asterisk are spinning sidebands. FIG. 11 : Proton decoupled 13 C CPMAS spectra of Form E atorvastatin magnesium. The peaks marked with an asterisk are spinning sidebands. FIG. 12 : Proton decoupled 13 C CPMAS spectra of Form F atorvastatin magnesium. The peaks marked with an asterisk are spinning sidebands. FIG. 13 : Proton decoupled 19 F MAS spectra of Form A atorvastatin magnesium. The peaks marked with an asterisk are spinning sidebands. FIG. 14 : Proton decoupled 19 F MAS spectra of Form B atorvastatin magnesium. The peaks marked with an asterisk are spinning sidebands. FIG. 15 : Proton decoupled 19 F MAS spectra of Form C atorvastatin magnesium. The peaks marked with an asterisk are spinning sidebands. FIG. 16 : Proton decoupled 19 F MAS spectra of Form D atorvastatin magnesium. The peaks marked with an asterisk are spinning sidebands. FIG. 17 : Proton decoupled 19 F MAS spectra of Form E atorvastatin magnesium. The peaks marked with an asterisk are spinning sidebands. FIG. 18 : Proton decoupled 19 F MAS spectra of Form F atorvastatin magnesium. The peaks marked with an asterisk are spinning sidebands. DETAILED DESCRIPTION OF THE INVENTION Form A, Form B, Form C, Form D, Form E, and Form F atorvastatin magnesium can be characterized by one or more of x-ray powder diffraction-, solid state NMR carbon chemical shift-, and solid state NMR fluorine chemical shift patterns. The “forms” of atorvastatin magnesium disclosed in the present invention may exist as ordered crystals, disordered crystals, liquid crystals, plastic crystals, mesophases, and the like. In X-ray powder diffractograms forms that are related through disorder will have essentially the same major peak positions but the disordering process will cause broadening of these peaks. For many of the weaker peaks, the broadening may be so severe that they are no longer visible above the background. The peak broadening caused by disorder may in addition cause errors in the location of the exact peak position. For solid state nuclear magnetic resonance (SSNMR) spectra, significant differences in chemical shifts may be seen from crystalline to disordered phases. EXPERIMENTAL X-Ray Powder Diffraction Form A, Form B, Form C, Form D, Form E, and Form F atorvastatin magnesium were characterized by their X-ray powder diffraction pattern. Thus, the X-ray powder diffraction patterns of Forms A, B, C, D, E, and F were carried out on a Bruker D8 Discover X-ray powder diffractometer with GADDS (General Area Diffraction Detector System) CS operating in reflection mode using CuK α radiation. The tube voltage and amperage were set to 40 kV and 40 mA, respectively. Scans were collected with the sample to detector distance set at 15.0 cm. The samples were scanned for a period of 60 seconds covering a range of 4.5° to 38.7° in 2θ. The diffractometer was calibrated for peak positions in 20 using a corundum standard. Samples were run in ASC-6 silicon sample holders purchased from Gem Dugout (State College, Pa.). All analyses were conducted at room temperature, which is generally 20°-30° C. Data were collected and integrated using GADDS for WNT software version 4.1.14T. Diffractograms were evaluated using DiffracPlus software, release 2003, with Eva version 8.0 (available from Bruker AXS, Inc., Madison, Wis.). To perform an X-ray diffraction measurement on a Bruker D8 Discover X-ray powder diffractometer with GADDS CS used for measurements reported herein, the sample is typically placed into a cavity in the middle of the silicon sample holder. The sample powder is pressed by a glass slide or equivalent to ensure a random surface and proper sample height. The sample holder is then placed into the Bruker instrument and the powder x-ray diffraction pattern is collected using the instrumental parameters specified above. Measurement differences associated with such X-ray powder diffraction analyses result from a variety of factors including: (a) errors in sample preparation (e.g., sample height), (b) instrument errors (e.g. flat sample errors), (c) calibration errors, (d) operator errors (including those errors present when determining the peak locations), and (e) the nature of the material (e.g. preferred orientation and transparency errors). Calibration errors and sample height errors often result in a shift of all the peaks in the same direction. Small differences in sample height when using a flat holder will lead to large displacements in XRPD peak positions. A systematic study showed that a sample height difference of 1 mm lead to peak shifts as high as 1° 2θ (Chen et al.; J Pharmaceutical and Biomedical Analysis, 2001; 26,63). These shifts can be identified from the X-ray diffractogram and can be eliminated by compensating for the shift (applying a systematic correction factor to all peak position values) or recalibrating the instrument. As mentioned above, it is possible to rectify measurements from the various instruments by applying a systematic correction factor to bring the peak positions into agreement. In general, this correction factor will bring the measured peak positions into agreement with the expected peak positions and is in the range of the expected 2θ value±0.2° 2θ. Tables 1-6 list peak positions in degrees 2θ, relative intensities, and relative peak widths for X-ray powder diffraction patterns of each form of atorvastatin magnesium disclosed in the present application. The relatively narrow peak positions were picked by the DiffracPlus with Eva version 8.0 software. The broader peak positions were visually determined. All peak positions were rounded to 0.1° 2θ. The following abbreviations are used in Tables 1-6 to describe the peak intensity (s=strong; m=medium; w=weak) and the peak width (b=broad (where broad refers to peak widths of between 0.2 and 1.0 degrees 2θ, sh=shoulder, vb=very broad (where very broad refers to peaks with >1 degrees 2θ peak width)). TABLE 1 XPRD Peak List for Form A Atorvastatin magnesium degree 2θ ± 0.2 Relative Intensity a Relative Peak Width b 9.3 w b 11.7 w b 14.3 w b 18.4 s b TABLE 2 XPRD Peak List for Form B Atorvastatin magnesium degree 2θ ± 0.2 Relative Intensity a Relative Peak Width b 5.3 w b 6.1 w b 8.0 w b 9.1 w b 10.5 w b, sh 10.9 m b 13.2 w b 13.9 w b 15.6 m b 16.1 w b 16.7 w b 17.2 w b 18.1 s b, sh 18.4 s b 19.8 s b 20.7 w b, sh 21.2 m b 21.8 m b 23.0 w b 24.1 w b 24.8 w b 25.6 w b 27.3 w b 29.1 w b TABLE 3 XPRD Peak List for Form C Atorvastatin magnesium degree 2θ ± 0.2 Relative Intensity a Relative Peak Width b 5.2 w b 6.6 w b 8.7 s b 9.8 w b 11.6 m b 12.3 m b 13.5 m b 14.6 m b 16.2 m b 18.7 s vb 19.9 s b, sh 23.2 s vb TABLE 4 XPRD Peak List for Form D atorvastatin magnesium degree 2θ ± 0.2 Relative Intensity a Relative Peak Width b 7.7 m b 8.8 m b 10.2 m b 11.9 w b 13.8 w b 15.9 s b 17.3 m b 18.7 s b 20.5 s vb 24.2 m b 26.7 w b 30.6 w vb TABLE 5 XPRD Peak List for Form E atorvastatin magnesium degree Relative Relative 2θ ± 0.2 Intensity a Peak Width b 8.4 m b 10.0 m b 11.1 w b 12.4 w b 14.0 w b 16.6 s b 17.9 s b 20.2 s b 22.0 s b, sh 23.1 s b, sh 26.3 m vb 30.3 m vb TABLE 6 XPRD Peak List for Form F atorvastatin magnesium degree Relative Relative 2θ ± 0.2 Intensity a Peak Width b 8.7 m b 10.1 s b 11.7 w b 12.7 w b 14.7 w b 16.1 s b 17.5 m b 18.5 m b 20.4 s b, sh 21.4 s vb, sh 23.7 m vb 26.8 w vb 30.4 m vb Table 7 lists combinations of 29 peaks for Forms A, B, C, D, E, and F atorvastatin magnesium, i.e., a set of x-ray diffraction lines that are unique to each form Form degree 2θ ± 0.2 A 9.3 14.3 18.4 B 6.1 8.0 10.9 19.8 23.0 C 5.2 6.6 12.3 D 7.7 20.5 24.2 E 8.4 16.6 17.9 F 8.7 10.1 11.7 16.1 Solid State NMR Spectroscopy For both 13 C—, and 19 F spectroscopy, approximately 80 mg of each sample were tightly packed into a 4 mm ZrO spinner. The spectra were collected at ambient conditions on a Bruker-Biospin 4 mm BL HFX CPMAS probe (Bruker BioSpin Corporation, 15 Fortune Drive, Manning Park, Billerica, Mass. 01821-3991) positioned into a wide-bore Bruker-Biospin Avance DSX 500 MHz NMR spectrometer. The samples were positioned at the magic angle and spun at 15.0 kHz, corresponding to the maximum specified spinning speed for the 4 mm spinners. The fast spinning speed minimized the intensities of the spinning side bands. The number of scans was adjusted to obtain adequate S/N. 13 C Spectroscopy The 13 C solid state spectra were collected using a proton decoupled cross-polarization magic angle spinning experiment (CPMAS). The Hartman-Hahn contact time was set to 2.0 ms. The proton decoupling field of approximately 90 kHz was applied. 2048 scans were collected. The recycle delay was adjusted to 7 seconds. The shift values are listed in Tables 8 to 13. The spectra were referenced using an external standard of crystalline adamantane, setting its upfield resonance to 29.5 ppm. TABLE 8 Carbon chemical shifts in ppm of Form A atorvastatin magnesium 13 C Chemical Shifts a [ppm] ± 0.2 Intensity b 180.3 0.8 177.9 0.6 168.0 0.1 166.6 1.3 163.5 0.5 161.6 1.1 141.7 1.5 140.3 0.8 134.9 1.2 129.3 4.7 124.4 12.0 123.3 2.9 118.7 3.5 117.4 4.3 116.1 3.6 70.3 4.0 68.0 1.7 67.2 1.5 42.3 1.5 36.4 4.2 26.6 0.1 22.2 4.2 TABLE 9 Carbon chemical shifts in ppm of Form B atorvastatin magnesium 13 C Chemical Shifts a [ppm] ± 0.2 Intensity b 183.5 1.2 180.4 Peak shoulder 178.7 0.8 166.0 2.3 163.6 1.4 161.7 2.0 139.3 5.0 136.1 5.2 133.8 4.6 132.2 3.4 129.6 12.0  126.8 4.5 125.4 4.3 122.9 1.5 120.9 1.8 119.7 1.8 118.3 1.7 115.8 4.4 72.9 2.8 71.0 5.0 45.6 2.2 43.3 6.8 41.6 5.4 41.0 5.5 27.1 5.4 26.9 5.1 24.9 3.6 24.3 4.0 22.1 1.9 19.5 8.9 TABLE 10 Carbon chemical shifts in ppm of Form C atorvastatin magnesium 13 C Chemical Shifts a [ppm] ± 0.2 Intensity b 180.6 0.8 179.9 0.8 167.6 1.4 163.3 1.1 161.5 1.4 141.2 0.9 139.1 1.6 135.3 4.6 133.3 3.9 129.2 12.0 126.3 4.3 123.1 3.8 119.7 3.6 117.8 3.5 116.0 3.1 71.1 1.6 67.6 1.3 43.1 3.5 42.4 3.5 26.6 3.4 22.4 4.4 TABLE 11 Carbon chemical shifts in ppm of Form D atorvastatin magnesium 13 C Chemical Shifts a [ppm] ± 0.2 Intensity b 183.1 1.2 182.4 1.6 179.9 1.8 176.5 0.6 165.9 2.3 163.4 1.4 162.7 1.4 161.4 2.1 160.8 1.8 141.3 1.0 138.6 6.5 136.9 2.8 136.4 3.0 135.0 6.3 134.4 5.1 132.6 4.7 131.5 7.4 130.5 8.4 129.4 12.0 128.3 10.2 126.4 2.7 124.1 5.5 123.2 2.8 121.0 6.9 117.1 5.0 115.2 3.9 114.3 2.0 71.5 1.8 70.4 2.4 69.3 4.3 67.4 2.5 66.5 4.5 46.5 2.4 45.6 3.5 44.2 4.4 43.2 5.9 41.4 2.7 39.7 4.0 37.6 0.8 27.2 6.8 26.8 5.8 24.6 2.7 23.7 3.5 22.9 3.4 21.5 1.8 20.9 1.3 19.1 3.9 TABLE 12 Carbon chemical shifts in ppm of Form E atorvastatin magnesium 13 C Chemical Shifts a [ppm] ± 0.2 Intensity b 181.0 0.8 166.4 2.2 162.6 1.4 160.7 1.9 137.8 5.0 135.2 8.5 131.5 6.1 129.6 11.0 128.9 12.0 123.8 3.9 122.0 3.6 117.7 2.6 115.6 1.7 114.9 1.6 67.9 1.7 67.0 1.9 43.2 3.9 41.7 2.7 41.1 2.6 26.6 5.3 24.0 4.3 21.0 3.6 TABLE 13 Carbon chemical shifts in ppm of Form F atorvastatin magnesium 13 C Chemical Shifts a [ppm] ± 0.2 Intensity b 182.6 1.1 180.0 1.3 166.0 3.0 162.9 1.0 162.6 1.1 161.1 1.6 160.7 1.6 138.2 6.5 136.3 3.2 135.1 8.2 131.4 7.1 130.4 5.6 129.4 9.5 128.5 12.0 124.0 5.5 121.0 4.5 117.4 2.9 115.1 1.7 114.2 1.8 69.1 1.6 67.4 1.9 66.4 3.6 46.4 1.7 45.6 2.0 43.2 2.8 40.0 1.8 39.3 1.6 27.0 4.5 23.4 3.4 23.1 3.4 19.4 3.3 In each of Tables 8-13, “a” is referenced to external sample of solid phase adamantane at 29.5 ppm; and “b” is defined as peak height. Intensities can vary depending on the actual setup of the CPMAS experimental parameters and the thermal history of the sample. CPMAS intensities are not necessarily quantitative. 19 F Spectroscopy The 19 F solid state spectra were collected using a proton decoupled magic angle spinning (MAS) experiment. The proton decoupling field of approximately 90 kHz was applied. 32 scans were collected. The recycle delay was set to 90 seconds to ensure acquisition of quantitative spectra. Proton longitudinal relaxation times ( 1 H T 1 ) were calculated based on a fluorine detected proton inversion recovery relaxation experiment. Fluorine longitudinal relaxation times ( 19 F T 1 ) were calculated based on a fluorine detected fluorine inversion recovery relaxation experiment. The spectra were referenced using an external sample of trifluoro-acetic acid (50% V/V in H 2 O), setting its resonance to −76.54 ppm. Tables 14 to 19 list the fluorine chemical shifts in ppm of Forms A, B, C, D, E, and F atorvastatin magnesium respectively. TABLE 14 19 F Chemical Shifts [ppm] ± 0.2 −108.4 (shoulder) −112.6 TABLE 15 19 F Chemical Shifts [ppm] ± 0.2 −115.7 TABLE 16 19 F Chemical Shifts [ppm] ± 0.2 −109.6 (shoulder) −113.0 TABLE 17 19 F Chemical Shifts [ppm] ± 0.2 −110.0 −111.7 −114.7 −119.8 TABLE 18 19 F Chemical Shifts a [ppm] ± 0.2 −113.2 −118.8 −122.1 (shoulder) TABLE 19 19 F Chemical Shifts [ppm] ± 0.2 −114.7 −118.8 (shoulder) −119.8 −122.3 The forms of atorvastatin magnesium described herein may exist in anhydrous forms as well as containing various amounts of water and/or solvents. Anhydrous, hydrated and solvated forms of atorvastatin magnesium are intended to be encompassed within the scope of the present invention. The forms of atorvastatin magnesium described herein, regardless of the extent of water and/or solvent having equivalent x-ray powder diffractograms are within the scope of the present invention. The new forms of atorvastatin magnesium described herein have advantageous properties. The ability of a material to form good tablets at commercial scale depends upon a variety of physical properties of the drug, such as, for example, the Tableting Indices described in Hiestand H. and Smith D., Indices of Tableting Performance, Powder Technology, 1984, 38; 145-159. These indices may be used to identify forms of atorvastatin magnesium which have superior tableting performance. One such index is the Brittle Fracture Index (BFI), which reflects brittleness, and ranges from 0 (good-low brittleness) to 1 (poor high brittleness). The present invention provides a process for the preparation of Forms A, B, C, D, E and F atorvastatin magnesium which comprises forming atorvastatin magnesium (e.g., from a solution or slurry in solvents) under conditions which yield Forms A, B, C, D, E and F atorvastatin magnesium. The precise conditions under which Forms A, B, C, D, E and F atorvastatin magnesium are formed may be empirically determined and described herein are methods which have been found to be suitable in practice. The compounds of the present invention can be prepared and administered in a wide variety of oral and parenteral dosage forms. The compounds of the present invention can be administered by injection, that is, intravenously, intramuscularly, intracutaneously, subcutaneously, intraduodenally, or intraperitoneally. Also, the compounds of the present invention can be administered by inhalation, for example, intranasally. Additionally, the compounds of the present invention can be administered transdermally. It will be obvious to those skilled in the art that the following dosage forms may comprise as the active component a compound of the present invention. For preparing pharmaceutical compositions from the compounds of the present invention, pharmaceutically acceptable carriers can be either solid or liquid. Solid form preparations include powders, tablets, pills, capsules, cachets, suppositories, and dispersible granules. A solid carrier can be one or more substances which may also act as diluents, flavoring agents, solubilizers, lubricants, suspending agents, binders, preservatives, tablet disintegrating agents, or an encapsulation material. In powders, the carrier is a finely divided solid which is in a mixture with the finely divided active component. In tablets, the active component is mixed with the carrier having the necessary binding properties in suitable proportions and compacted in the shape and size desired. The powders and tablets preferably contain from two or ten to about seventy percent of the active compound. Suitable carriers are magnesium carbonate, methylcellulose, sodium carboxymethylcellulose, a low melting wax, cocoa butter, and the like. The term ‘preparation’ is intended to include the formulation of the active compound with encapsulating material as a carrier providing a capsule in which the active component, with or without other carriers, is surrounded by a carrier, which is thus in association with it. Similarly, cachets and lozenges are included. Tablets, powders, capsules, pills, cachets, and lozenges can be used as solid dosage forms suitable for oral administration. For preparing suppositories, a low melting wax, such as a mixture of fatty acid glycerides or cocoa butter, is first melted and the active component is dispersed homogeneously therein, as by stirring. The molten homogeneous mixture is then poured into convenient sized molds, allowed to cool, and thereby to solidfy. Liquid form preparations include solutions, suspensions, retention enemas, and emulsions, for example water or water propylene glycol solutions. For parenteral injection, liquid preparations can be formulated in solution in aqueous polyethylene glycol solution. Aqueous solutions suitable for oral use can be prepared by dissolving the active component in water and adding suitable colorants, flavors, stabilizing and thickening agents, as desired. Aqueous suspensions suitable for oral use can be made by dispersing the finely divided active component in water with viscous material, such as natural or synthetic gums, resins, methylcellulose, sodium carboxymethylcellulose, and other well-known suspending agents. Also included are solid form preparations which are intended to be converted, shortly before use, to liquid form preparations for oral administration. Such liquid forms include solutions, suspensions, and emulsions. These preparations may contain, in addition to the active component, colorants, flavors, stabilizers, buffers, artificial and natural sweeteners, dispersants, thickeners, solubilizing agents, and the like. The pharmaceutical preparation is preferably in unit dosage form. In such form, the preparation is subdivided into unit doses containing appropriate quantities of the active component. The unit dosage form can be a packaged preparation, the package containing discrete quantities of preparation, such as packeted tablets, capsules, and powders in vials or ampoules. Also, the unit dosage form can be a capsule, tablet, cachet, or lozenge itself, or it can be the appropriate number of any of these in packaged form. The quantity of active component in a unit dosage preparation may be varied or adjusted from 0.5 mg to 100 mg, preferably 2.5 to 80 mg according to the particular application and the potency of the active component. The composition can, if desired, also contain other compatible therapeutic agents. In therapeutic use as hypolipidemic and/or hypocholesterolemic agents and agents to treat BPH, osteoporosis, and Alzheimer's disease, the Forms A, B, C, D, E, and F atorvastatin magnesium utilized in a method of this invention are administered at the initial dosage of about 2.5 mg to about 80 mg daily. Useful daily doses includes those in the range of about 2.5 mg to about 20 mg. The dosages, however, may be varied depending upon the requirements of the patient, the severity of the condition being treated, and the compound being employed. Determination of the proper dosage for a particular situation is within the skill of the art. Generally, treatment is initiated with smaller dosages which are less than the optimum dose of the compound. Thereafter, the dosage is increased by small increments until the optimum effect under the circumstance is reached. For convenience, the total daily dosage may be divided and administered in portions during the day if desired. Form A of atorvastatin magnesium may be prepared by dissolving the lactone form of atorvastatin (U.S. Pat. No. 5,273,995) in a solvent in which both the lactone and sodium salt forms are soluble. Useful solvents include lower weight alcohols, such as methanol and ethanol, water or tetrahydrofuran (THF) or mixtures thereof. NaOH is added to the solution, with stirring, at a temperature from about 45° C. to about 55° C., followed by slow addition of a magnesium salt, such as MgCl 2 or a hydrated form thereof. The mixture can them be cooled to ambient temperature to yield a suspension and a precipitate, which can be filtered from the suspension. Water can then be slowly added to the resulting solution with stirring to produce a second precipitate of atorvastatin magnesium Form A, which can then be removed by filtration. Atorvastatin magnesium Form B may be prepared by suspending a sample of Form A, discussed above, in an aromatic organic solvent, such as benzene, xylene, ortho-xylene, para-xylene, meta-xylene, toluene, etc., at a temperature from about 40° C. to about 80° C. and stirring until From B atorvastatin magnesium is obtained. Atorvastatin magnesium Form C may be obtained by suspending a sample of Form A, described above, in a mixture of acetonitrile and water at ambient temperature, with the acetonitrile being no more than 80% but no less than 50% of the acetonitrile/water mixture (volume/volume). The resulting mixture may then be stirred at ambient temperature until Form C is produced. Form D atorvastatin magnesium may be prepared by suspending a sample of Form A, described above, in a mixture of about 9/1 (volume/volume) 2-propanol/water at ambient temperature and stirring the resulting mixture until Form D is obtained. Form E atorvastatin magnesium may be prepared by suspending a sample of Form A, described above, in water at ambient temperature and stirring until Form E is obtained. Form F atorvastatin magnesium may be obtained by suspending a sample of Form A, described above, in water at a temperature from about 45° C. to about 100° C. and stirring the resulting mixture until Form F is obtained. Those skilled in the art will understand the forms of atorvastatin magnesium will be obtained in different amounts depending upon the amount of time spent in the steps above. Amounts of the desired forms may be obtained in periods from one day to 50 days by the methods above. It will also be understood that methods known in the art may be used to obtain the desired atorvastatin magnesium material from the resulting suspension, such as centrifuge filtration. The following nonlimiting examples illustrate methods for preparing the compounds of the invention: Example 1 [R—(R*,R*)]-2-(4-fluorophenyl)-β,δ-dihydroxy-5-(1-methylethyl)-3-phenyl-4-[(phenylamino)carbonyl]−1H-pyrrole-1-heptanoic acid hemi magnesium salt (Forms A, B, C, D, E, and F atorvastatin magnesium) Form A Atorvastatin Magnesium A 6.0 g sample of the lactone form of atorvastatin (U.S. Pat. No. 5,273,995) was dissolved in 100 mL of methanol at room temperature. Approximately 11.8 mL of 1N NaOH (1.05 mol equivalents) was then added to the mixture. The solution was then stirred at 50° C. for approximately 1 hour. A solution of 1.19 g MgCl 2 .6H 2 O in 5 mL of H 2 O (0.55 mol equivalents) was then slowly added to the reaction mixture. The mixture was then cooled to room temperature and the resulting precipitate was removed by vacuum filtration through a 0.45-μm nylon membrane filter. Approximately 100 mL of H 2 O was then slowly added to the filtered solution, which caused a white precipitate to form. The resulting suspension was then stirred for approximately 30 minutes. The solid sample was then isolated by vacuum filtration. The filtered solid was then dried under vacuum at 70° C. for approximately 2 hours to afford 5.8 g of Form A atorvastatin magnesium. Form B Atorvastatin Magnesium A 50 mg sample of Form A atorvastatin magnesium (prepared as described above) was slurried in 0.25 mL of ortho-xylene at 45° C. for 28 days using magnetic stirring at 400 rpm. The solid sample was then isolated by centrifuge filtration through a 0.45-μm nylon membrane filter. The filtered solid was then air dried under ambient conditions for approximately 5 hours to afford Form B atorvastatin magnesium. Form C Atorvastatin Magnesium A 50 mg sample of Form A atorvastatin magnesium (prepared as described above) was slurried in 0.75 mL of acetonitrile:water (8:2, v/v) at ambient temperature for 28 days using magnetic stirring at 300 rpm. The solid sample was then isolated by centrifuge filtration through a 0.45-μm nylon membrane filter. The filtered solid was then air dried under ambient conditions for approximately 5 hours to afford Form C atorvastatin magnesium. Form D Atorvastatin Magnesium A 50 mg sample of Form A atorvastatin magnesium (prepared as described above) was slurried in 1 mL of 2-propanol:water (9:1, v/v) at ambient temperature for 28 days using magnetic stirring at 300 rpm. The solid sample was then isolated by centrifuge filtration through a 0.45-μm nylon membrane filter. The filtered solid was then air dried under ambient conditions for approximately 5 hours to afford Form D atorvastatin magnesium. Form E Atorvastatin Magnesium A 50 mg sample of Form A atorvastatin magnesium (prepared as described above) was slurried in 3 mL of water at ambient temperature for 28 days using magnetic stirring at 300 rpm. The solid sample was then isolated by centrifuge filtration through a 0.45-μm nylon membrane filter. The filtered solid was then air dried under ambient conditions for approximately 5 hours to afford Form E atorvastatin magnesium. Form F Atorvastatin Magnesium A 50 mg sample of Form A atorvastatin magnesium (prepared as described above) was slurried in 1 mL of water at 45° C. for 28 days using magnetic stirring at 300 rpm at 400 rpm. The solid sample was then isolated by centrifuge filtration through a 0.45-μm nylon membrane filter. The filtered solid was then air dried under ambient conditions for approximately 5 hours to afford Form F atorvastatin magnesium.

Novel forms of atorvastatin magnesium salt designated Form A, Form B, Form C, Form D, Form E, and Form F, pharmaceutical compositions containing such compounds, methods for their preparation and methods utilizing the compounds for treatment of hyperlipidemia, hypercholesterolemia, osteoporosis, benign prostatic hyperplasia (BPH) and Alzheimer's disease are described.

[0001] This application claims priority from U.S. provisional applications Ser. No. 60/632,079, filed on Nov. 30, 2004, entitled “Horizontal perspective representation”, which is incorporated herein by reference. FIELD OF INVENTION [0002] This invention relates to a three-dimensional simulator system, and in particular, to a computer representation system using 3D horizontal perspective. BACKGROUND OF THE INVENTION [0003] Three dimensional (3D) capable electronics and computing hardware devices and real-time computer-generated 3D computer graphics have been a popular area of computer science for the past few decades, with innovations in visual, audio and tactile systems. [0004] Ever since humans began to communicate through pictures, they faced a dilemma of how to accurately represent the three-dimensional world they lived in. Sculpture was used to successfully depict three-dimensional objects, but was not adequate to communicate spatial relationships between objects and within environments. To do this, early humans attempted to “flatten” what they saw around them onto two-dimensional, vertical planes (e.g. paintings, drawings, tapestries, etc.). Scenes where a person stood upright, surrounded by trees, were rendered relatively successfully on a vertical plane. But how could they represent a landscape, where the ground extended out horizontally from where the artist was standing, as far as the eye could see? [0005] The answer is three dimensional illusions. The two dimensional pictures must provide a numbers of cues of the third dimension to the brain to create the illusion of three dimensional images. This effect of third dimension cues can be realistically achievable due to the fact that the brain is quite accustomed to it. The three dimensional real world is always and already converted into two dimensional (e.g. height and width) projected image at the retina, a concave surface at the back of the eye. And from this two dimensional image, the brain, through experience and perception, generates the depth information to form the three dimension visual image from two types of depth cues: monocular (one eye perception) and binocular (two eye perception). In general, binocular depth cues are innate and biological while monocular depth cues are learned and environmental. [0006] In binocular depth cues, the disparity of the retinal images due to the separation of the two eyes is used to create the perception of depth. The effect is called stereoscopy where each eye receives a slightly different view of a scene, and the brain fuses them together using these differences to determine the ratio of distances between nearby objects. There are also depth cues with only one eye, called monocular depth cues, to create an impression of depth on a flat image. [0007] Perspective drawing, together with relative size, is most often used to achieve the illusion of three dimension depth and spatial relationships on a flat (two dimension) surface, such as paper or canvas. Through perspective, three dimension objects are depicted on a two dimension plane, but “trick” the eye into appearing to be in three dimension space. Some perspective examples are military, cavalier, isometric, and dimetric, as shown at the top of FIG. 1 . [0008] Of special interest is the most common type of perspective, called central perspective, shown at the bottom left of FIG. 1 . Central perspective, also called one-point perspective, is the simplest kind of “genuine” perspective construction, and is often taught in art and drafting classes for beginners. FIG. 2 further illustrates central perspective. Using central perspective, the chess board and chess pieces look like three dimension objects, even though they are drawn on a two dimensional flat piece of paper. Central perspective has a central vanishing point, and rectangular objects are placed so their front sides are parallel to the picture plane. The depth of the objects is perpendicular to the picture plane. All parallel receding edges run towards a central vanishing point. The viewer looks towards this vanishing point with a straight view. When an architect or artist creates a drawing using central perspective, they must use a single-eye view. That is, the artist creating the drawing captures the image by looking through only one eye, which is perpendicular to the drawing surface. [0009] The vast majority of images, including central perspective images, are displayed, viewed and captured in a plane perpendicular to the line of vision. Viewing the images at angle different from 90° would result in image distortion, meaning a square would be seen as a rectangle when the viewing surface is not perpendicular to the line of vision. [0010] Central perspective is employed extensively in 3D computer graphics, for a myriad of applications, such as scientific, data visualization, computer-generated prototyping, special effects for movies, medical imaging, and architecture, to name just a few. [0011] FIG. 3 illustrates a view volume in central perspective to render computer-generated 3D objects to a computer monitor's vertical, 2D viewing surface. In FIG. 3 , a near clip plane is the 2D plane onto which the x, y, z coordinates of the 3D objects within the view volume will be rendered. Each projection line starts at the camera point, and ends at a x, y, z coordinate point of a virtual 3D object within the view volume. [0012] The basic of prior art 3D computer graphics is the central perspective projection. 3D central perspective projection, though offering realistic 3D illusion, has some limitations is allowing the user to have hands-on interaction with the 3D display. [0013] There is a little known class of images that we called it “horizontal perspective” where the image appears distorted when viewing head on, but displaying a three dimensional illusion when viewing from the correct viewing position. In horizontal perspective, the angle between the viewing surface and the line of vision is preferably 45° but can be almost any angle, and the viewing surface is preferably horizontal (wherein the name “horizontal perspective”), but it can be any surface, as long as the line of vision forming a not-perpendicular angle to it. [0014] Horizontal perspective images offer realistic three dimensional illusion, but are little known primarily due to the narrow viewing location (the viewer's eyepoint has to be coincide precisely with the image projection eyepoint), and the complexity involving in projecting the two dimensional image or the three dimension model into the horizontal perspective image. [0015] The generation of horizontal perspective images requires considerably more expertise to create than conventional perpendicular images. The conventional perpendicular images can be produced directly from the viewer or camera point. One need simply open one's eyes or point the camera in any direction to obtain the images. Further, with much experience in viewing three dimensional depth cues from perpendicular images, viewers can tolerate significant amount of distortion generated by the deviations from the camera point. In contrast, the creation of a horizontal perspective image does require much manipulation. Conventional camera, by projecting the image into the plane perpendicular to the line of sight, would not produce a horizontal perspective image. Making a horizontal drawing requires much effort and very time consuming. Further, since human has limited experience with horizontal perspective images, the viewer's eye must be positioned precisely where the projection eyepoint point is to avoid image distortion. And therefore horizontal perspective, with its difficulties, has received little attention. [0016] The present invention recognizes that the personal computer is perfectly suitable for horizontal perspective display. It is personal, thus it is designed for the operation of one person, and the computer, with its powerful microprocessor, is well capable of rendering various horizontal perspective images to the viewer. Further, horizontal perspective offers open space display of 3D images, thus allowing the hand-on interaction of the end users. SUMMARY OF THE INVENTION [0017] Thus the present invention discloses a method to represent the data into realistic, hand-on 3D images using horizontal perspective. The present invention horizontal perspective representation takes the raw data, information and knowledge and renders them into horizontal perspective 3D images. The horizontal perspective images are projected into the open space with various peripheral devices that allow the end user to manipulate the images with hands or hand-held tools. The raw data, information and knowledge can be in the form of file format, 3D file format, database, digital books including texts and pictures or drawings. [0018] The data is stored in a file, preferably using a 3D file format so that the 3D images can be represented by horizontal perspective when needed. The data can be scanned pictures, 3D scanned objects, and multi-view scanned images to render left and right views to form horizontal perspective images. [0019] For example, the present invention horizontal perspective representation can be used in a doctor office. When a patient is examined, the doctor can call up the patient's name from the computer system, and the computer system displays a 3D horizontal perspective image of the patient. The image is taken from the patient earlier and stored in 3D file format in the computer. This is similar to the selection of the patient's name and having a 2D picture of the patient displaying. The different is the 3D horizontal perspective images, allowing the doctor to interact with the image through hand-on simulations. Horizontal perspective images provide realistic 3D images while allow the viewer to interact or virtually touch all portions of the images. [0020] The data can further be stored in a database. The data can be a complete data, or can share a portion with the main section of the database. For example, the patient's representation by 3D horizontal perspective can be a generic image with generic face and generic body. The specific patient data can then be inserted into the horizontal perspective representation, such as the patient name, sex, or any relevant information for the case at hand. [0021] The data can be measured data, for example, data from a MRI scan, brain scan, DNA measures, cell structure measures. These data can be stored in a database under the patient. Thus when the doctor chooses the patient's name, and elects to see the particular aspect of the situation, the database can be available to present the information. For example, if the patient suffers a broken bone, the doctor can call the MRI scan data from the database and represention can zoom in the section selected, in this case, the broken bone. The broken bone is showing in 3D horizontal perspective, with zoom and rotation capability and even layer stripping capability to allow realistic viewing of the current situation. The representation is possible due to the available data stored in the database. If the data is not available, the 3D representation will be just a generic space-holder image. That signifies that the data is not available and if needed, the test should be ordered and the data collected. [0022] With zooming capability, the doctor can start with the patient body, and then zoom to the particular section. For example, if the patient has a broken bone in the foot, the zoom could show the section of that bone. The showing is made possible with the data taken earlier from the patient foot, such as an x-ray test. [0023] Further zooming is also possible, to the cell level and even DNA level for genetic evaluation. The present invention horizontal perspective representation takes the data in various formats, such as x-ray data, MRI data, NDA data, cell data, and put together to show a realistic 3D image of the data. This will allow the fast viewing and adsorption of knowledge and quick evaluation and analysis and diagnotic of the case. A major advantage of the present invention is the convertion of the number or bits and bytes from the data ar database and represent them in 3D image where the interpretation can be made easier. [0024] Furthermore, the 3D representation can gather data from books to compare the current case with the text book learning. The doctor can call on book written on the subject and show with 3D horizontal perspective. The knowledge transferred from book to 3D horizontal perspective can make the learning and evaluation quicker and easier. If books are not enough, email or phone or visit with an expert can also be made and the images transferred by horizontal perspective. [0025] The representation by 3D horizontal perspective from the data collected in a file, a database, or a book can accelerate the learning capability. Horizontal perspective representation can be a superior way to display raw data, information and knowledge. BRIEF DESCRIPTION OF THE DRAWINGS [0026] FIG. 1 shows the various perspective drawings. [0027] FIG. 2 shows a typical central perspective drawing. [0028] FIG. 3 illustrates a central perspective camera model. [0029] FIG. 4 shows the comparison of central perspective (Image A) and horizontal perspective (Image B). [0030] FIG. 5 shows the central perspective drawing of three stacking blocks. [0031] FIG. 6 shows the horizontal perspective drawing of three stacking blocks. [0032] FIG. 7 shows the method of drawing a horizontal perspective drawing. [0033] FIG. 8 shows mapping of the 3D object onto the horizontal plane. [0034] FIG. 9 shows mapping of the 3D object onto the horizontal plane. [0035] FIG. 10 shows the two-eye view of 3D simulation. [0036] FIG. 11 shows the various 3D peripherals. [0037] FIG. 12 shows the computer interacting in 3D simulation environment. [0038] FIG. 13 shows the computer tracking in 3D simulation environment. [0039] FIG. 14 shows the mapping of virtual attachments to end of tools. DETAILED DESCRIPTION OF THE INVENTION [0040] The disclosed invention takes the data, information and knowledge and represents them in 3D horizontal perspective. More specifically, these new inventions enable real-time computer-generated 3D simulations representation of other real-world physical knowledge. The present invention horizontal perspective representation is build upon the horizontal perspective system capable of projecting three dimensional illusions based on horizontal perspective projection. [0041] Horizontal perspective is a little-known perspective, of which we found only two books that describe its mechanics: Stereoscopic Drawing (©1990) and How to Make Anaglyphs (©1979, out of print). Although these books describe this obscure perspective, they do not agree on its name. The first book refers to it as a “free-standing anaglyph,” and the second, a “phantogram.” Another publication called it “projective anaglyph” (U.S. Pat. No. 5,795,154 by G. M. Woods, Aug. 18, 1998). Since there is no agreed-upon name, we have taken the liberty of calling it “horizontal perspective.” Normally, as in central perspective, the plane of vision, at right angle to the line of sight, is also the projected plane of the picture, and depth cues are used to give the illusion of depth to this flat image. In horizontal perspective, the plane of vision remains the same, but the projected image is not on this plane. It is on a plane angled to the plane of vision. Typically, the image would be on the ground level surface. This means the image will be physically in the third dimension relative to the plane of vision. Thus horizontal perspective can be called horizontal projection. [0042] In horizontal perspective, the object is to separate the image from the paper, and fuse the image to the three dimension object that projects the horizontal perspective image. Thus the horizontal perspective image must be distorted so that the visual image fuses to form the free standing three dimensional figure. It is also essential the image is viewed from the correct eye points, otherwise the three dimensional illusion is lost. In contrast to central perspective images which have height and width, and project an illusion of depth, and therefore the objects are usually abruptly projected and the images appear to be in layers, the horizontal perspective images have actual depth and width, and illusion gives them height, and therefore there is usually a graduated shifting so the images appear to be continuous. [0043] FIG. 4 compares key characteristics that differentiate central perspective and horizontal perspective. Image A shows key pertinent characteristics of central perspective, and Image B shows key pertinent characteristics of horizontal perspective. [0044] In other words, in Image A, the real-life three dimension object (three blocks stacked slightly above each other) was drawn by the artist closing one eye, and viewing along a line of sight perpendicular to the vertical drawing plane. The resulting image, when viewed vertically, straight on, and through one eye, looks the same as the original image. [0045] In Image B, the real-life three dimension object was drawn by the artist closing one eye, and viewing along a line of sight 45° to the horizontal drawing plane. The resulting image, when viewed horizontally, at 45° and through one eye, looks the same as the original image. [0046] One major difference between central perspective showing in Image A and horizontal perspective showing in Image B is the location of the display plane with respect to the projected three dimensional image. In horizontal perspective of Image B, the display plane can be adjusted up and down, and therefore the projected image can be displayed in the open air above the display plane, i.e. a physical hand can touch (or more likely pass through) the illusion, or it can be displayed under the display plane, i.e. one cannot touch the illusion because the display plane physically blocks the hand. This is the nature of horizontal perspective, and as long as the camera eyepoint and the viewer eyepoint is at the same place, the illusion is present. In contrast, in central perspective of Image A, the three dimensional illusion is likely to be only inside the display plane, meaning one cannot touch it. To bring the three dimensional illusion outside of the display plane to allow viewer to touch it, the central perspective would need elaborate display scheme such as surround image projection and large volume. [0047] FIGS. 5 and 6 illustrate the visual difference between using central and horizontal perspective. To experience this visual difference, first look at FIG. 5 , drawn with central perspective, through one open eye. Hold the piece of paper vertically in front of you, as you would a traditional drawing, perpendicular to your eye. You can see that central perspective provides a good representation of three dimension objects on a two dimension surface. [0048] Now look at FIG. 6 , drawn using horizontal perspective, by sifting at your desk and placing the paper lying flat (horizontally) on the desk in front of you. Again, view the image through only one eye. This puts your one open eye, called the eye point at approximately a 45° angle to the paper, which is the angle that the artist used to make the drawing. To get your open eye and its line-of-sight to coincide with the artist's, move your eye downward and forward closer to the drawing, about six inches out and down and at a 45° angle. This will result in the ideal viewing experience where the top and middle blocks will appear above the paper in open space. [0049] Again, the reason your one open eye needs to be at this precise location is because both central and horizontal perspective not only defines the angle of the line of sight from the eye point; they also define the distance from the eye point to the drawing. This means that FIGS. 5 and 6 are drawn with an ideal location and direction for your open eye relative to the drawing surfaces. However, unlike central perspective where deviations from position and direction of the eye point create little distortion, when viewing a horizontal perspective drawing, the use of only one eye and the position and direction of that eye relative to the viewing surface are essential to seeing the open space three dimension horizontal perspective illusion. [0050] FIG. 7 is an architectural-style illustration that demonstrates a method for making simple geometric drawings on paper or canvas utilizing horizontal perspective. FIG. 7 is a side view of the same three blocks used in FIG. 6 . It illustrates the actual mechanics of horizontal perspective. Each point that makes up the object is drawn by projecting the point onto the horizontal drawing plane. To illustrate this, FIG. 7 shows a few of the coordinates of the blocks being drawn on the horizontal drawing plane through projection lines. These projection lines start at the eye point (not shown in FIG. 7 due to scale), intersect a point on the object, then continue in a straight line to where they intersect the horizontal drawing plane, which is where they are physically drawn as a single dot on the paper. When an architect repeats this process for each and every point on the blocks, as seen from the drawing surface to the eye point along the line-of-sight the horizontal perspective drawing is complete, and looks like FIG. 6 . [0051] Notice that in FIG. 7 , one of the three blocks appears below the horizontal drawing plane. With horizontal perspective, points located below the drawing surface are also drawn onto the horizontal drawing plane, as seen from the eye point along the line-of-site. Therefore when the final drawing is viewed, objects not only appear above the horizontal drawing plane, but may also appear below it as well—giving the appearance that they are receding into the paper. If you look again at FIG. 6 , you will notice that the bottom box appears to be below, or go into, the paper, while the other two boxes appear above the paper in open space. [0052] The generation of horizontal perspective images requires considerably more expertise to create than central perspective images. Even though both methods seek to provide the viewer the three dimension illusion that resulted from the two dimensional image, central perspective images produce directly the three dimensional landscape from the viewer or camera point. In contrast, the horizontal perspective image appears distorted when viewing head on, but this distortion has to be precisely rendered so that when viewing at a precise location, the horizontal perspective produces a three dimensional illusion. [0053] The horizontal perspective display system promotes horizontal perspective projection viewing by providing the viewer with the means to adjust the displayed images to maximize the illusion viewing experience. By employing the computation power of the microprocessor and a real time display, the horizontal perspective display, comprising a real time electronic display capable of re-drawing the projected image, together with a viewer's input device to adjust the horizontal perspective image. By re-display the horizontal perspective image so that its projection eyepoint coincides with the eyepoint of the viewer, the horizontal perspective display of the present invention can ensure the minimum distortion in rendering the three dimension illusion from the horizontal perspective method. The input device can be manually operated where the viewer manually inputs his or her eyepoint location, or change the projection image eyepoint to obtain the optimum three dimensional illusions. The input device can also be automatically operated where the display automatically tracks the viewer's eyepoint and adjust the projection image accordingly. The horizontal perspective display system removes the constraint that the viewers keeping their heads in relatively fixed positions, a constraint that create much difficulty in the acceptance of precise eyepoint location such as horizontal perspective or hologram display. [0054] The horizontal perspective display system can further a computation device in addition to the real time electronic display device and projection image input device providing input to the computational device to calculating the projectional images for display to providing a realistic, minimum distortion three dimensional illusion to the viewer by coincide the viewer's eyepoint with the projection image eyepoint. The system can further comprise an image enlargement/reduction input device, or an image rotation input device, or an image movement device to allow the viewer to adjust the view of the projection images. [0055] The input device can be operated manually or automatically. The input device can detect the position and orientation of the viewer eyepoint, to compute and to project the image onto the display according to the detection result. Alternatively, the input device can be made to detect the position and orientation of the viewer's head along with the orientation of the eyeballs. The input device can comprise an infrared detection system to detect the position the viewer's head to allow the viewer freedom of head movement. Other embodiments of the input device can be the triangulation method of detecting the viewer eyepoint location, such as a CCD camera providing position data suitable for the head tracking objectives of the invention. The input device can be manually operated by the viewer, such as a keyboard, mouse, trackball, joystick, or the like, to indicate the correct display of the horizontal perspective display images. [0056] The horizontal perspective image projection employs the open space characteristics, and thus enables an end user to interact physically and directly with real-time computer-generated 3D graphics, which appear in open space above the viewing surface of a display device, i.e. in the end user's own physical space. [0057] In horizontal perspective, the computer hardware viewing surface is preferably situated horizontally, such that the end-user's line of sight is at a 45° angle to the surface. Typically, this means that the end user is standing or seated vertically, and the viewing surface is horizontal to the ground. Note that although the end user can experience hands-on simulations at viewing angles other than 45° (e.g. 55°, 30° etc.), it is the optimal angle for the brain to recognize the maximum amount of spatial information in an open space image. Therefore, for simplicity's sake, we use “45°” throughout this document to mean “an approximate 45 degree angle”. Further, while horizontal viewing surface is preferred since it simulates viewers' experience with the horizontal ground, any viewing surface could offer similar three dimensional illusion experience. The horizontal perspective illusion can appear to be hanging from a ceiling by projecting the horizontal perspective images onto a ceiling surface, or appear to be floating from a wall by projecting the horizontal perspective images onto a vertical wall surface. [0058] The horizontal perspective display creates a “Hands-On Volume” and a “Inner-Access Volume.” The Hands-On Volume is situated on and above the physical viewing surface. Thus the end user can directly, physically manipulate simulations because they co-inhabit the end-user's own physical space. This 1:1 correspondence allows accurate and tangible physical interaction by touching and manipulating simulations with hands or hand-held tools. The Inner-Access Volume is located underneath the viewing surface and simulations within this volume appear inside the physically viewing device. Thus simulations generated within the Inner-Access Volume do not share the same physical space with the end user and the images therefore cannot be directly, physically manipulated by hands or hand-held tools. That is, they are manipulated indirectly via a computer mouse or a joystick. [0059] One major difference between the present invention and prior art graphics engine is the projection display. Existing 3D-graphics engine uses central-perspective and therefore a vertical plane to render its view volume while in the present invention simulator, a “horizontal” oriented rendering plane vs. a “vertical” oriented rendering plane is required to generate horizontal perspective open space images. The horizontal perspective images offer much superior open space access than central perspective images. [0060] To accomplish the Hands-On Volume simulation, a synchronization is requires between the computer-generated world and their physical real-world equivalents. Among other things, this synchronization insures that images are properly displayed, preferably through a Reference Plane calibration. [0061] A computer monitor or viewing device is made of many physical layers, individually and together having thickness or depth. For example, a typical CRT-type viewing device would include a the top layer of the monitor's glass surface (the physical “View Surface”), and the phosphor layer (the physical “Image Layer”), where images are made. The View Surface and the Image Layer are separate physical layers located at different depths or z coordinates along the viewing device's z axis. To display an image the CRT's electron gun excites the phosphors, which in turn emit photons. This means that when you view an image on a CRT, you are looking along its z axis through its glass surface, like you would a window, and seeing the light of the image coming from its phosphors behind the glass. Thus without a correction, the physical world and the computer simulation are shifted by this glass thickness. [0062] An Angled Camera point is a point initially located at an arbitrary distance from the displayed and the camera's line-of-site is oriented at a 45° angle looking through the center. The position of the Angled Camera in relation to the end-user's eye is critical to generating simulations that appear in open space on and above the surface of the viewing device. [0063] Mathematically, the computer-generated x, y, z coordinates of the Angled Camera point form the vertex of an infinite “pyramid”, whose sides pass through the x, y, z coordinates of the Reference/Horizontal Plane. FIG. 8 illustrates this infinite pyramid, which begins at the Angled Camera point and extending through the Far Clip Plane. [0064] As a projection line in either the Hands-On and Inner-Access Volume intersects both an object point and the offset Horizontal Plane, the three dimensional x, y, z point of the object becomes a two-dimensional x, y point of the Horizontal Plane (see FIG. 9 ). Projection lines often intersect more than one 3D object coordinate, but only one object x, y, z coordinate along a given projection line can become a Horizontal Plane x, y point. The formula to determine which object coordinate becomes a point on the Horizontal Plane is different for each volume. For the Hands-On Volume it is the object coordinate of a given projection line that is farthest from the Horizontal Plane. For the Inner-Access Volume it is the object coordinate of a given projection line that is closest to the Horizontal Plane. In case of a tie, i.e. if a 3D object point from each volume occupies the same 2D point of the Horizontal Plane, the Hands-On Volume's 3D object point is used. [0065] The hands-on simulator also allows the viewer to move around the three dimensional display and yet suffer no great distortion since the display can track the viewer eyepoint and re-display the images correspondingly, in contrast to the conventional prior art three dimensional image display where it would be projected and computed as seen from a singular viewing point, and thus any movement by the viewer away from the intended viewing point in space would cause gross distortion. [0066] The display system can further comprise a computer capable of re-calculate the projected image given the movement of the eyepoint location. The horizontal perspective images can be very complex, tedious to create, or created in ways that are not natural for artists or cameras, and therefore require the use of a computer system for the tasks. To display a three-dimensional image of an object with complex surfaces or to create animation sequences would demand a lot of computational power and time, and therefore it is a task well suited to the computer. Three dimensional capable electronics and computing hardware devices and real-time computer-generated three dimensional computer graphics have advanced significantly recently with marked innovations in visual, audio and tactile systems, and have producing excellent hardware and software products to generate realism and more natural computer-human interfaces. [0067] The horizontal perspective display system are not only in demand for entertainment media such as televisions, movies, and video games but are also needed from various fields such as education (displaying three-dimensional structures), technological training (displaying three-dimensional equipment). There is an increasing demand for three-dimensional image displays, which can be viewed from various angles to enable observation of real objects using object-like images. The horizontal perspective display system is also capable of substitute a computer-generated reality for the viewer observation. The systems may include audio, visual, motion and inputs from the user in order to create a complete experience of three dimensional illusions. [0068] The input for the horizontal perspective system can be two dimensional image, several images combined to form one single three dimensional image, or three dimensional model. The three dimensional image or model conveys much more information than that a two dimensional image and by changing viewing angle, the viewer will get the impression of seeing the same object from different perspectives continuously. [0069] The horizontal perspective display can further provide multiple views or “Multi-View” capability. Multi-View provides the viewer with multiple and/or separate left-and right-eye views of the same simulation. Multi-View capability is a significant visual and interactive improvement over the single eye view. In Multi-View mode, both the left eye and right eye images are fused by the viewer's brain into a single, three-dimensional illusion. The problem of the discrepancy between accommodation and convergence of eyes, inherent in stereoscopic images, leading to the viewer's eye fatigue with large discrepancy, can be reduced with the horizontal perspective display, especially for motion images, since the position of the viewer's gaze point changes when the display scene changes. [0070] FIG. 10 helps illustrate these two stereoscopic and time simulations. The computer-generated person has both eyes open, a requirement for stereoscopic 3D viewing, and therefore sees the bear cub from two separate vantage points, i.e. from both a right-eye view and a left-eye view. These two separate views are slightly different and offset because the average person's eyes are about 2 inches apart. Therefore, each eye sees the world from a separate point in space and the brain puts them together to make a whole image. There are existing stereoscopic 3D viewing devices that require more than a separate left- and right-eye view. But because the method described here can generate multiple views it works for these devices as well. [0071] The distances between people's eyes vary but in the above example we are using the average of 2 inches. It is also possible for the end user to provide their personal eye separation value. This would make the x value for the left and right eyes highly accurate for a given end user and thereby improve the quality of their stereoscopic 3D view. [0072] In Multi-View mode, the objective is to simulate the actions of the two eyes to create the perception of depth, namely the left eye and the right eye sees slightly different images. Thus Multi-View devices that can be used in the present invention include methods with glasses such as anaglyph method, special polarized glasses or shutter glasses, methods without using glasses such as a parallax stereogram, a lenticular method, and mirror method (concave and convex lens). [0073] In anaglyph method, a display image for the right eye and a display image for the left eye are respectively superimpose-displayed in two colors, e.g., red and blue, and observation images for the right and left eyes are separated using color filters, thus allowing a viewer to recognize a stereoscopic image. The images are displayed using horizontal perspective technique with the viewer looking down at an angle. As with one eye horizontal perspective method, the eyepoint of the projected images has to be coincide with the eyepoint of the viewer, and therefore the viewer input device is essential in allowing the viewer to observe the three dimensional horizontal perspective illusion. From the early days of the anaglyph method, there are much improvements such as the spectrum of the red/blue glasses and display to generate much more realism and comfort to the viewers. [0074] In polarized glasses method, the left eye image and the right eye image are separated by the use of mutually extinguishing polarizing filters such as orthogonally linear polarizer, circular polarizer, elliptical polarizer. The images are normally projected onto screens with polarizing filters and the viewer is then provided with corresponding polarized glasses. The left and right eye images appear on the screen at the same time, but only the left eye polarized light is transmitted through the left eye lens of the eyeglasses and only the right eye polarized light is transmitted through the right eye lens. [0075] Another way for stereoscopic display is the image sequential system. In such a system, the images are displayed sequentially between left eye and right eye images rather than superimposing them upon one another, and the viewer's lenses are synchronized with the screen display to allow the left eye to see only when the left image is displayed, and the right eye to see only when the right image is displayed. The shuttering of the glasses can be achieved by mechanical shuttering or with liquid crystal electronic shuttering. In shuttering glass method, display images for the right and left eyes are alternately displayed on a CRT in a time sharing manner, and observation images for the right and left eyes are separated using time sharing shutter glasses which are opened/closed in a time sharing manner in synchronism with the display images, thus allowing an observer to recognize a stereoscopic image. [0076] Other way to display stereoscopic images is by optical method. In this method, display images for the right and left eyes, which are separately displayed on a viewer using optical means such as prisms, mirror, lens, and the like, are superimpose-displayed as observation images in front of an observer, thus allowing the observer to recognize a stereoscopic image. Large convex or concave lenses can also be used where two image projectors, projecting left eye and right eye images, are providing focus to the viewer's left and right eye respectively. A variation of the optical method is the lenticular method where the images form on cylindrical lens elements or two dimensional array of lens elements. [0077] Depending on the stereoscopic 3D viewing device used, the horizontal perspective display continues to display the left- and right-eye images, as described above, until it needs to move to the next display time period. An example of when this may occur is if the bear cub moves his paw or any part of his body. Then a new and second simulated image would be required to show the bear cub in its new position. This process of generating multiple views via the nonstop incrementing of display time continues as long as the horizontal perspective display is generating real-time simulations in stereoscopic 3D. [0078] By rapidly display the horizontal perspective images, three dimensional illusion of motion can be realized. Typically, 30 to 60 images per second would be adequate for the eye to perceive motion. For stereoscopy, the same display rate is needed for superimposed images, and twice that amount would be needed for time sequential method. [0079] The display rate is the number of images per second that the display uses to completely generate and display one image. This is similar to a movie projector where 24 times a second it displays an image. Therefore, 1/24 of a second is required for one image to be displayed by the projector. But the display time could be a variable, meaning that depending on the complexity of the view volumes it could take 1/120, 1/12 or ½ a second for the computer to complete just one display image. Since the display was generating a separate left and right eye view of the same image, the total display time is twice the display time for one eye image. [0080] The system further includes technologies employed in computer “peripherals”. FIG. 11 shows examples of such peripherals with six degrees of freedom, meaning that their coordinate system enables them to interact at any given point in an (x, y, z) space. The examples of such peripherals are Space Glove, Space Tracker, or Character Animation Device. [0081] Some peripherals provide a mechanism that enables the simulation to perform this calibration without any end-user involvement. But if calibrating the peripheral requires external intervention than the end-user will accomplish this through a calibration procedure. Once the peripheral is calibrated, the simulation will continuously track and map the peripheral. [0082] With the peripherals linking to the simulator, the user can interact with the display model. The simulation can get the inputs from the user through the peripherals, and manipulate the desired action. With the peripherals properly matched with the physical space and the display space, the simulator can provide proper interaction and display. The peripheral tracking can be done through camera triangulation or through infrared tracking devices. [0083] The simulator can further include 3D audio devices. Object Recognition is a technology that uses cameras and/or other sensors to locate simulations by a method called triangulation. Triangulation is a process employing trigonometry, sensors, and frequencies to “receive” data from simulations in order to determine their precise location in space. It is for this reason that triangulation is a mainstay of the cartography and surveying industries where the sensors and frequencies they use include but are not limited to cameras, lasers, radar, and microwave. 3D Audio also uses triangulation but in the opposite way 3D Audio “sends” or projects data in the form of sound to a specific location. But whether you're sending or receiving data the location of the simulation in three-dimensional space is done by triangulation with frequency receiving/sending devices. By changing the amplitudes and phase angles of the sound waves reaching the user's left and right ears, the device can effectively emulate the position of the sound source. The sounds reaching the ears will need to be isolated to avoid interference. The isolation can be accomplished by the use of earphones or the like. [0084] FIG. 12 shows an end-user looking at an image of a bear cub. Since the cub appears in open space above the viewing surface the end-user can reach in and manipulate the cub by hand or with a handheld tool. It is also possible for the end-user to view the cub from different angles, as they would in real life. This is accomplished though the use of triangulation where the three real-world cameras continuously send images from their unique angle of view to the computer. This camera data of the real world enables the computer to locate, track, and map the end-user's body and other real-world simulations positioned within and around the computer monitor's viewing surface. [0085] FIG. 12 also shows the end-user viewing and interacting with the bear cub, but it includes 3D sounds emanating from the cub's mouth. To accomplish this level of audio quality requires physically combining each of the three cameras with a separate speaker. The cameras' data enables the computer to use triangulation in order to locate, track, and map the end-user's “left and right ear”. And since the computer is generating the bear cub, it knows the exact location of the cub's mouth. By knowing the exact location of the end-user's ears and the cub's mouth the computer uses triangulation to sends data, by modifying the spatial characteristics of the audio, making it appear that 3D sound is emanating from the cub's computer-generated mouth. Note that other sensors and/or transducers may be used as well. [0086] Triangulation works by separating and positioning each camera/speaker device such that their individual frequency receiving/sending volumes overlap and cover the exact same area of space. If you have three widely spaced frequency receiving/sending volumes covering the exact same area of space than any simulation within the space can accurately be located. [0087] As shown in FIG. 13 , the simulator then performs simulation recognition by continuously locating and tracking the end-user's “left and right eye” and their “line-of-sight”, continuously map the real-world left and right eye coordinates precisely where they are in real space, and continuously adjust the computer-generated cameras coordinates to match the real-world eye coordinates that are being located, tracked, and mapped. This enables the real-time generation of simulations based on the exact location of the end-user's left and right eye. It also allows the end-user to freely move their head and look around the images without distortion. [0088] The simulator then perform simulation recognition by continuously locating and tracking the end-user's “left and right ear” and their “line-of-hearing”, continuously map the real-world left- and right-ear coordinates precisely where they are in real space, and continuously adjust the 3D Audio coordinates to match the real-world ear coordinates that are being located, tracked, and mapped. This enables the real-time generation of sounds based on the exact location of the end-user's left and right ears. It also allows the end-user to freely move their head and still hear sounds emanating from their correct location. [0089] The simulator then perform simulation recognition by continuously locating and tracking the end-user's “left and right hand” and their “digits,” i.e. fingers and thumbs, continuously map the real-world left and right hand coordinates precisely where they are in real space, and continuously adjust the coordinates to match the real-world hand coordinates that are being located, tracked, and mapped. This enables the real-time generation of simulations based on the exact location of the end-user's left and right hands, allowing the end-user to freely interact with simulations. [0090] The simulator then perform simulation recognition by continuously locating and tracking “handheld tools”, continuously map these real-world handheld tool coordinates precisely where they are in real space, and continuously adjust the coordinates to match the real-world handheld tool coordinates that are being located, tracked, and mapped. This enables the real-time generation of simulations based on the exact location of the handheld tools, allowing the end-user to freely interact with simulations. [0091] FIG. 14 is intended to assist in further explaining the handheld tools. The end-user can probe and manipulated the simulations by using a handheld tool, which in FIG. 14 looks like a pointing device. [0092] A “computer-generated attachment” is mapped in the form of a computer-generated simulation onto the tip of a handheld tool, which in FIG. 14 appears to the end-user as a computer-generated “eraser”. The end-user can of course request that the computer maps any number of computer-generated attachments to a given handheld tool. For example, there can be different computer-generated attachments with unique visual and audio characteristics for cutting, pasting, welding, painting, smearing, pointing, grabbing, etc. And each of these computer-generated attachments would act and sound like the real device they are simulating when they are mapped to the tip of the end-user's handheld tool.

The present invention discloses a method to represent the data into realistic, hands-on 3D images using horizontal perspective. The present invention horizontal perspective representation takes the raw data, information and knowledge and renders them into horizontal perspective 3D images. The horizontal perspective images are projected into the open space with various peripheral devices that allow the end user to manipulate the images with hands or hand-held tools. The raw data, information and knowledge can be in the form of file format, 3D file format, database, digital books including texts and pictures or drawings.

FIELD OF THE INVENTION The present invention relates generally to spread spectrum communications systems, processes and systems that use spread spectrum communication, and, in particular embodiments to such systems, processes and devices which improve the performance of spread spectrum communications systems in the presence of adverse signal conditions. DESCRIPTION OF THE RELATED ART It is likely that the first navigational system used by man was the sun. It rose in the east and set in the west and as long as travel occurred in daylight hours general direction could be obtained from the sun's position in the sky. With the advent of commerce on the seas it became necessary to ascertain direction at night, and so stellar navigation was born. In order to increase accuracy, stellar and solar navigation techniques were improved and augmented through the use of maps, charts, and instruments such as the astrolabe and compass. Even augmented by such instruments, stellar and solar navigation was error prone and traveling from point A to point B was still, to some extent, a matter of trial and error. With the advent of radio, and particularly powerful commercial radio stations land based radio direction finding (RDF) came into being. The principle behind RDF is relatively simple. A navigator can tune to a radio station using a directional antenna to find the directional bearing of the radio station. The navigator can then could tune to a second radio station and find the bearing of that station. By knowing the bearing and map location of both stations the navigator's position can be calculated. Continuing advances in long distance air travel necessitated the ability to guide aircraft accurately. RDF was used to satisfy this requirement and land based beacons were established for the purpose of navigation. These beacons quickly became indispensable to all aviation and to ships as well. The Global Positioning System (GPS) is also based on radio navigation, a difference being that the beacons are no longer stationary and are no longer land based. The GPS system is a satellite based navigation system having a network of 24 satellites, plus on orbit spares, orbiting the earth 11,000 nautical miles in space, in six evenly distributed orbits. Each satellite orbits the earth every twelve hours. A prime function of the GPS satellites is to serve as a clock. Each satellite derives its signals from an on board 10.23 MHz Cesium atomic clock. Each satellite transmits a spread spectrum signal with it's own individual pseudo noise (PN) code. By transmitting several signals over the same spectrum using distinctly different PN coding sequences the satellites may share the same bandwidth without interfering with each other. The code used in the GPS system is 1023 bits long and is sent at a rate of 1.023 megabits per second, yielding a time mark, sometimes called a “chip” approximately once every micro-second. The sequence repeats once every millisecond and is called the course acquisition code (C/A code). Every 20th cycle the code can change phase and is used to encode a 1500 bit long message which contains an “almanac” containing data on all the other satellites. There are 32 PN codes designated by the GPS authority. Twenty four of them belong to current satellites in orbit, the 25th PN code is designated as assigned to any satellite. The remaining codes are spare codes which may be used in new satellites to replace old or failing units. A GPS receiver may, using the different PN sequences, search the signal spectrum looking for a match. If the GPS receiver finds a match, then it has identified the satellite which has generated the signal. Ground based GPS receivers may use a variant of radio direction finding (RDF) methodology, called triangulation, in order to determine the position of the ground based GPS receiver. The GPS position determination is different from the RDF technology in that the radio beacons are no longer stationary they are satellites moving through space at a speed of about 1.8 miles per second as they orbit the earth. By being space based, the GPS system can be used to establish the position of virtually any point on Earth using methods such as triangulation. The triangulation method depends on the GPS receiving unit obtaining a time signal from a satellite. By knowing the actual time and comparing it to the time that is received from the satellite the receiver, the distance to the satellite can be calculated. If, for example, the GPS satellite is 12,000 miles from the receiver then the receiver must be somewhere on the location sphere defined by the radius of 12,000 from that satellite. If the GPS receiver then ascertains the position of a second satellite it can calculate the receiver's location based on a location sphere around the second satellite. The two sphere's intersect and form a circle, and so the GPS receiver must be located somewhere within that location circle. By ascertaining the distance to a third satellite the GPS receiver can project a location sphere around the third satellite. The third satellite's location sphere will then intersect the location circle produced by the intersection of the location spheres of the first two satellites at just two points. By determining the location sphere of one more satellite, whose location sphere will intersect one of the two possible location points, the precise position of the GPS receiver is determined. As a consequence, the exact time may also be determined, because there is only one time offset that can account for the positions of all the satellites. The triangulation method may yield positional accuracy on the order of 30 meters, however the accuracy of GPS position determination may be degraded due to signal strength and multipath reflections. As many as 11 satellites may be received by a GPS receiver at one time. In certain environments such as a canyon, some satellites may be blocked out, and the GPS position determining system may depend for position information on satellites that have weaker signal strengths, such as satellites near the horizon. In other cases overhead foliage may reduce the signal strength that is received by the GPS receiver unit. In either case the signal strength may be so reduced as to make acquisition of enough satellites to determine position difficult. In such cases the GPS receiver may take a number of attempts to lock onto the satellites and increased time to lock onto signals suitable for position determination, or it may not be able to lock on to the signals at all. In the case of multipath reflections, a signal may be reflected from a structure, or even the ground, so that the signal's path to the receiver is indirect. An indirect path is longer than a direct path and will make the time the signal has to travel to the receiver longer and the distance to the satellite will appear to be farther away as a result. The resulting position calculated by the receiver may contain an error. There are multiple ways of using radio spectrum to communicate. For example, in frequency division multiple access (FDMA) the frequency band is divided into a series of frequency slots and different transmitters are allotted different frequency slots. n time division multiple access (TDMA) systems in which the time that each transmitter may broadcast is limited to a time slot, such that transmitters transmit their messages one after another, only transmitting during their allotted period. With TDMA, the frequency upon which each transmitter transmits may be a constant frequency or may be continuously changing (frequency hopping). A third way of allotting the radio spectrum to multiple users is through the use of code division multiple access (CDMA) also known as spread spectrum. In CDMA all the users transmit on the same frequency band all of the time. Each user has a dedicated code that is used to separate that user's transmission from all others. This code is commonly referred to as a spreading code, because it spreads the information across the band. The code is also commonly referred to as a Pseudo Noise or PN code. In a CDMA transmission, each bit of transmitted data is replaced by that particular user's spreading code if the data to be transmitted is a “1”, and is replaced by the inverse of the spreading, code if the data to be transmitted is “0”. To decode the transmission at the receiver it is necessary to “despread” the code. The despreading process takes the incoming signal and multiplies it by the spreading code and sums the result. This process is commonly known as correlation, and it is commonly said that the signal is correlated with the PN code. The result of the despreading process is that the original data may be separated from all the other transmissions, and the original signal may be recovered. A property of the PN codes that are used in CDMA systems is that the presence of one spread spectrum code does not change the result of the decoding of another code. The property that one code does not interfere with the presence of another code is often referred to as orthogonality, and codes which possess this property are said to be orthogonal. Although the term CDMA is used widely to describe a type of telephone communications the term spread spectrum may also be applied. Those terms will be used interchangeably herein. The process of extracting data from a CDMA signal is commonly known by many terms such as correlating, decoding, and despreading. Those terms will be used interchangeably herein. The codes used by a spread spectrum system are commonly referred to by a variety of terms including, but not limited to, PN (Pseudo Noise) codes, PR (Pseudo Random) codes, spreading code, despreading code, and orthogonal code Those terms will be used interchangeably herein. It is because the transmission bandwidth is large compared with the data bandwidth that CDMA is often referred to as spread spectrum. Spread spectrum has a number of benefits. One benefit being that because the data transmitted is spread across the spectrum, spread spectrum can tolerate interference better than some other transmission protocol. Another benefit is that messages can be transmitted with low power and still be decoded. The Global Positioning System uses spread spectrum technology to convey its data to ground units. The use of spread spectrum is especially advantageous in the GPS systems. Spread spectrum technology enables GPS receivers to operate on a single frequency, thus saving the additional electronics needed to switch and tune other bands if multiple frequencies were used. Spread Spectrum also can minimize the power consumption requirements of the GPS system, for example to require 50 watts or less and tolerate substantial interference. Although the GPS system is available widely, there are conditions which can degrade its performance or block its use. Improvements in the reception of GPS signals are constantly being sought. There is a need for greater sensitivity in receiving GPS signals to improve the performance of ground based receivers. CDMA (Code Division Multiple Access) is used as an alternative to FDMA (Frequency Division Multiple Access) and TDMA (Time Division Multiple Access) in portable phone systems. There has been widespread debate over the superiority of TDMA versus CDMA. Both technologies continually vie for market acceptance and market share, and because of this competition improvements in each are constantly being sought. There is therefore a need in the art for improvement of the sensitivity of CDMA portable phone systems. SUMMARY OF THE DISCLOSURE Accordingly, preferred embodiments of the present invention are directed to systems which incorporate spread spectrum technology. GPS receivers, cordless and portable telephones are examples of systems which may employ spread spectrum technology, and are used herein to illustrate preferred embodiments of the invention. Spread spectrum technology can be advantageous in applications where signals need to be transmitted with low power. This is'so because the spreading process introduces redundancy into the signal being transmitted by replacing each data bit by a series of bits commonly called Pseudo Noise, or PN codes. This redundancy enables the signal to be decoded even though parts of it may be obscured by noise. To receive the data a spread spectrum receiver must determine that the PN code is present. To determine that a PN code is present in a received signal, the received signal must be compared, bit by bit, to the PN code. This process of comparing a signal bit by bit to a PN code is commonly known as correlation. A perfect match will indicate the presence of the signal. Less than a perfect match, however, may also indicate the presence of the signal. This is so because noise may disturb the bit pattern of the signal broadcast, with the result that not all bits of the signal match the code. One of the advantages of spread spectrum is that the signal is redundant so that, even if a number of bits are destroyed by noise, the remaining bits may be detected and the signal decoded. To determine that a particular spread spectrum is present, the received signal must be compared, bit by bit, to the PN code, and the results of the comparison examined. If the result is a 100% match between the PN code and the signal received a signal containing the code is probably present. If, however, there is less than a 100% match the signal may still be present. To examine for the presence of the signal a process commonly known as hypothesis testing is employed. Hypothesis testing examines a signal for a certain percentage match. If that percentage match, between the signal and the PN code, is met or exceeded, the hypothesis testing proceeds to test for a greater percentage threshold. The process of testing for increasingly higher percentage match thresholds, between the signal and the PN code, terminates when a final threshold is passed and it is determined that the signal is present. The hypothesis testing process may also terminate if successive attempts are not successful in passing the percentage matching thresholds. If a certain number of successive attempts fail to pass the successive thresholds, of the hypothesis tester, it is determined that the signal, containing the PN code, is not present. The hypotheses testing process can insure with a high probability that a signal is present, even if a 100% match is never obtained. The hypotheses testing process helps to eliminate false positive matches, and also helps to prevent false negatives (erroneous indications that the particular PN code is not present). The hypothesis testing process has a weakness in that it may take a long time and multiple attempts to determine that a weak signal is present. Multiple attempts at matching the PN code to the signal may be necessary because, in case of weak signal conditions, random noise can easily interfere with the signal, destroying the bit pattern. The process of hypothesis testing depends on multiple samplings of the signal, thereby, on average, negating the effect of random noise. The hypothesis testing process also has a weakness in that reflected, or multipath, signals may be strong enough to cause a false indication. Embodiments of the disclosure provide several improvements upon the process of hypothesis testing and of spread spectrum signal processing in general. One preferred embodiment measures the signal strength of the incoming spread spectrum signal and adjusts the hypotheses testing levels depending on the level of received signal strength. Decreasing the threshold levels, in the case where a spread spectrum signal is weak, will decrease the time that will be needed to identify that a signal bearing a certain PN code is present. Increasing the threshold levels, when the signal is strong, will help prevent multipath signals from being falsely identified as being the broadcast signal, bearing the PN code, sought. In addition, various embodiments utilize both old and novel methods of determining signal strength. New methods, employed in several embodiments of the disclosure, use a PN code not present in the spread spectrum signal being decoded, to determine the signal strength. The code, which is not present in the spread spectrum signal received, is correlated with the spread spectrum signal. The result of the correlation with the unused code is indicative of the signal strength. In a GPS embodiment of the disclosure the 25th GPS code is correlated with the incoming signal. The 25th GPS code is one which has been identified by the GPS authority as not being present in any GPS satellite. Correlation of the GPS signal with this code yields a result that is indicative of the strength of the spread spectrum signal. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an illustration of a GPS receiver concurrently receiving signals from four GPS satellites. FIG. 2 a block diagram representation of a portion of a GPS satellite. FIG. 3 is a generalized block diagram representation of a portion of an example GPS receiver. FIG. 4 is, a tabular representation of the spreading and despreading process illustrated with a spreading code of length 8. FIG. 5 is a flow diagram illustrating a generalized example of a hypothesis testing procedure. FIG. 6 is an block diagram illustrating an example of a modified hypothesis testing procedure as it may be found in a GPS receiver or within a portable CDMA phone. FIG. 7 is a block diagram of an alternate implementation of the correlator in FIG. 6 . FIG. 8 is a block diagram of detailed representation of an embodiment of an example GPS receiver according to an embodiment of the invention. FIG. 9 is a block diagram of an example embodiment of modified hypothesis testing incorporated into a spread spectrum receiver system. FIG. 10 is a block diagram example embodiment of a signal strength determination in a GPS receiver being used to switch an active antenna. DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS A first example embodiment described herein relates to GPS receiver system, process and device. FIG. 1 is an illustration of a GPS receiver 103 on earth 101 concurrently receiving signals from four GPS satellites 105 , 107 , 109 , and 111 in space. The four GPS satellites 105 , 107 , 109 and 111 continually broadcast a high accuracy time signal which is received by GPS receiver 103 . The signal from each of the GPS satellites 105 , 107 , 109 , and 111 must respectively travel different paths 113 , 115 , 117 and 119 . The time signal from each satellite is received includes the time that the time necessary for signals from the satellites need to travel the different paths to the receiver. The satellites also broadcast data about their position as well as a time signal. By knowing the positions of the satellites and using the time signals to compute the distance of the receiver from the satellites the receiver can accurately determine it's position. FIG. 2 is a block diagram of a portion 201 of a GPS satellite for spread spectrum encoding and the transmission of data. Block 203 represents satellite data that will be encoded for transmission. This data includes location information for the satellite, as well as delay and error information. Block 205 represents what is commonly referred to as almanac data, which is data on all of the GPS satellites. Block 207 represents the current time which is generated by the high accuracy atomic time standard within the satellite. The information from blocks 203 , 205 , and 207 are encoded in the proper format by the data encoder 209 . The encoded data is then sent to the spreading unit 211 , which correlates the encoded data by multiplying it bit by bit with one of 24 spreading codes as provided by storage device 213 . Each of the 24 spreading codes represents a particular satellite on orbit. The chip rate is equal to the data rate multiplied time the length of the spreading code. The data stream is then sent to the modulator 219 where the carrier frequency 1.57542 GHz as provided by generator 217 is modulated by it. The resulting signal is sent to the antenna 221 of the satellite for broadcast. FIG. 3 is a generalized block diagram representation of a receiving portion 301 of an example GPS receiver unit. The antenna 303 receives signals from one or more GPS satellites. The received signals are provided to a demodulator 305 , which demodulates the signals using a carrier frequency, for example 1.57542 GHz, as represented by block 307 . The resulting data signal 309 corresponds to the signal 215 of the satellite. The spread spectrum signal 309 is then despread in the correlator 311 using PN code 313 . The data decoder 315 can then decode the data needed which will be used to triangulate the position of the receiving unit. FIG. 4 shows a tabular representation of a spectrum spreading and despreading, or correlating process illustrated with a spreading code of length 8. Three 8 bit spreading codes are illustrated. Spreading code 1, 401 , is 11000011, Spreading code 2, 403 , is 00110011, Spreading code 3, 405 , is 10010110. To spread data using a spreading code 1 for example, if a data “1” is to be sent, a copy of the code as in column 407 , 11000011, is sent in its place. If a data “0” is to be sent, the inverse code, with each bit inverted, as shown in column 409 , 00111100 is sent in its place. In other words if spreading code 1 is used and data representing a “1” is to be sent then the code 11000011 is sent, similarly if data representing a “0” is to be sent then the code 00111100 is sent. The despreading process involves a mathematical manipulation, i.e. correlation with the received data. For example suppose that data is to be received from a sender who is using spreading code 1n. To despread the data, first all the “0”s of the received code are replaced by −1 for computational purposes. If 11000011 (code 1's representation of a “1”) is received, it is replaced by 11−1−1−1−111 as shown in line 411 . The received code is then multiplied bit by bit by the computational representation of the spreading code, i.e. 11−1−1−1−111 as shown in line 413 . The bitwise;product of the spreading code and the data received is shown in line 415 as 1+1+1+1+1+1+1+=+8, the product of the correlation is +8 and thus a binary “1” is detected. If 00111100 (code 1's representation of a “0” as shown in column 409 ) is received it's replaced by −1−11111−1−1 as shown in line 417 . The received code is then multiplied bit by bit by the computational representation of the spreading code, i.e. 11−1−1−1−111, as shown in line 419 . The bitwise product as shown in line 421 is −1−1−1−1−1−1−1=−8, the product of the correlation is 8 and a binary “0” is detected. If the signal had been correlated with the inverse of the spreading code, the product would have been a +8. The methods are equivalent and the selection can be made based on the particular implementation used. A situation where the data transmitted by a signal spread with code 1 is despreaded by spreading code 2 is illustrated in lines 423 , 425 , and 427 . As an example a spreading code 1 data bit of “1”, i.e. 11000011, is received. As shown in line 423 the 0 bits are replaced by −1 for computational purposes. Then the received code 11−1−1−1−111 is multiplied bit by bit with the spreading code 2, e.g. −1−111−1−111 as shown in line 425 . The product of multiplying a spreading code 1 data “1” with spreading code 2 is shown in line 427 as −1−1−1−1+1+1+1+1=0. That is, when a spreading code 1 representation of a data “1” is multiplied bit by bit and summed with spreading code 2, i.e. data spread with code 1 is correlated with code 3, the result is 0, in other words no data is detected. Therefore a transmission of a binary 1 using spreading code #1 will not interfere with data interpretation using spreading code 2. A situation where the data transmitted by a signal spread with code 1 and despread using spreading code 3 is illustrated in lines 429 , 431 , and 433 . As an example, a spreading code 1 data bit of “1”, i.e. 11000011, is received. As shown in line 423 the 0 bits are replaced by −1 for computational purposes. Then the received code 11−1−1−1−111 is multiplied bit by bit with the spreading code 3, e.g. 1−1−11−111−1 as shown in line 431 . The product of multiplying a spreading code 1 data “1” is shown inline 427 as 1−1+1−1+1−1+1−1=0. That is, when a spreading code 1 representation of a data “1” is multiplied bit by bit and summed with spreading code 3, the result is 0, in such case no data is detected. Therefore, the transmission of a binary 1 using spreading code 1 will not interfere with data interpretation using spreading code 3. The above examples illustrate the fact that data transmitted with one code does not interfere with data transmitted with another code. This property whereby transmission of data by one code does not mask the data transmitted by another code is commonly referred to orthogonality, and codes having such properties are said to be orthogonal. The previous illustrations were performed with a class of codes known as Walsh codes, which are perfectly orthogonal. The number of Walsh codes, however, is limited. The number of Walsh codes that exist is equal to the number of bits in the spreading code. Because this situation is restrictive, a family of codes known as pseudo noise (PN) codes, which are nearly orthogonal, have been developed. PN codes are codes that repeat periodically and have the property that if they are multiplied by themselves and the bits summed the result is a number that is the same as the length of the sequence. That is, under ideal conditions the correlation product of a PN code of length N with a signal containing that code will be the value N. For example the GPS PN code length is 1023, so that if we correlate the GPS signal with a code which is contained in the signal the output of the correlator will be 1023, if the signal is not present then the value will be −1. PN codes also have the property that, if they are correlated with the signal containing that particular PN code which is.shifted in time by any number of bits, then the result is a −1. This means that the correlation must be synchronized in time with the spread spectrum signal bearing the code in order to produce an output equal to the length of the code. There are literally millions of PN codes, and so they are appropriate for use within portable phoneosystems. An advantage of a spread spectrum system is its greater noise toleration and low power signal all as for decoding in harsh environments. Since signals in a spread spectrum system can be very low, this can lead to difficulty in acquiring a signal, and identifying that the signal is present. A process known as hypothesis testing can be used in order to facilitate the acquisition process. The process compares successively higher values to the output .of the correlator to determine if a signal is present. This process aids acquisition in two ways. First, if there is an erroneously high correlation value (i.e. potential multipath signals), it is not instantly identified as a correctly decoded signal, because it must pass several successive thresholds. Second, if there is a large amount of transient interference resulting in a low correlation number, the signal is not instantly rejected as incorrect. As a result of the hypothesis testing process, the signal must be examined over several sample sets to determine if it has been correctly acquired (i.e. the correct PN code selected and correctly aligned with the incoming received signal sequence. FIG. 5 is a flow diagram illustrating a general example of a hypothesis testing procedure. In the first block of the procedure the parameters are initialized. The current threshold level, CT that is being tested is initialized to the first threshold level, i.e. 1 so that the lowest level is compared first. A counter, X, which keeps track of how many times the correlated value of the signal has failed to exceed a hypothesis testing threshold, is initialized to 0. Also, in the initialization block, the incoming signal is sampled for the first time. After initialization in block 503 , control passes on to block 505 . In block 505 , the received signal is correlated with a PN code using bit by bit multiplication. Control then passes on to decision block 507 . In decision block 507 the result of the correlation of the signal to the PN code is compared to the current threshold level, CT. If the correlation has not resulted in a number greater than the current threshold value, then X is incremented and control passes to decision block 509 . If the correlation has resulted in a number whose value is greater than the current threshold CT, then control passes to decision block 515 . In decision block 515 a determination of whether CT is the maximum threshold level is made. If the current value of CT is the maximum threshold value, then all intended thresholds have been met and the correct PN code must have been used and properly aligned with the incoming signal. Control then passes to block 517 , where the algorithm terminates with the acquisition of the signal and the determination that the particular PN code is present. If decision block 515 finds that the final threshold level has not been passed, control passes to block 519 where CT, representing the threshold level that is being examined, is incremented to the next level. From block 519 control passes to block 511 , in which the signal is resampled. After the signal has been resampled, control passes to block 505 and the process continues. If the correlated value in block 507 is not greater than the nth threshold value, then X is incremented in block 508 and control passes to decision block 509 . In block 509 , a determination as to whether the comparison as indicated by X has failed Y times is made, where Y is a number determined by the particular implementation of the procedure. If the comparison has failed Y times, then control passes to block 513 , indicating that the signal has not been acquired using the present PN code and the procedure terminates. If decision block 509 finds that the comparison has not failed Y times, then there is still a possibility that a correct PN code has been found to acquire the incoming signal and control passes to block 511 , which resamples the signal. Control then passes to block 505 and the procedure continues. FIG. 6 shows an example implementation of hypothesis testing in a GPS receiver or a portable CDMA phone. In this example hypothesis tester 601 , a received signal 603 containing spread spectrum information is compared to a PN code 605 in a correlator 607 . The output is then sent to a computation unit 609 where the decoding data may be averaged, or large deviations discarded, or other mathematical operations such as counting the number of correlations attempted may be performed. The computation unit may also pass the data on to the next stage, the comparator 613 , unaltered depending on the particular application. The comparator then compares the value received from the computational unit to a first threshold level 611 . If the unit matches or exceeds the first threshold level it will enable a comparison by second correlator, 617 , by sending it an enable signal 615 . The second comparison will not be performed unless the first level comparison is successful. Correlator 617 is also connected to the received signal 603 , containing spread spectrum information, and the same PN code 605 used in the first correlator. The output of the second correlator 617 is coupled to a second computation unit 619 with similar potential functionality to that of computation unit 609 . When the second computational unit 619 has completed its operations on the output of second correlator 617 the result is coupled to the comparison unit 623 , where it is compared with a second threshold level 621 . If the comparison is such that the results match or exceed threshold level number 2 , then second comparator 623 couples an enable signal 625 to the next level, thereby activating the next level. This process continues evaluating the incoming signal against a PN code through N thresholds. The Nth correlator 627 is also connected to the received signal 603 containing spread spectrum information and the PN code 605 to which it is to be compared, as were the previous stages. The output of the Nth correlator 627 is coupled to the Nth computational unit 629 . When the Nth computational unit 629 has completed its operations on the decoding performed in the correlator 627 the result is coupled to the comparator unit 633 , where it is compared with the final Nth threshold level 631 . If the comparison is such that the results match or exceed threshold level N then comparator N 633 will output a flag 635 that indicates that PN code 635 has been found to decode one of the messages present in the received signal 603 . The hypothesis testing unit illustrated in FIG. 6 is an example implementation. There are a variety of possible alterations which may be implemented depending on a variety of factors such as the amount of hardware available, the computing resources available, the specifications for signal acquisition time which must be met, and other details which may vary from implementation to implementation. For example, there may not be multiple decoding units (i.e. 607 , 617 , 627 ), computational units (i.e. 609 , 619 , 629 ), or comparison (i.e. 613 , 623 , 633 ) units available, and thus the same functional units may be used repetitively for each stage of the hypothesis testing. The decoding, computational, and comparison units may be omitted and their functions implemented using a microcomputer and appropriate software. The individual blocks themselves may also exhibit a great variety of variation. For example, each correlator may actually contain more than one correlation unit. Some implementations may use multiple comparison units to compare the signal received to the PN code because of difficulties in synchronizing the two signals precisely. Such a variation is illustrated in FIG. 7 . FIG. 7 is a block diagram of a multiple comparator 701 . The received signal 703 and the PN code 705 are coupled into the multiple comparator 701 and are compared in a first stage C 1 , 707 , An output 709 is generated as the result of the comparison. The PN code is also delayed in delay block D 1 , 711 and a delayed version is 713 is coupled to comparator C 2 715 , which compares the delayed PN code to the received signal 703 , and produces an output 717 . The delayed PN code 713 is then put through a further delay D 2 in block 719 and the further delayed PN code 721 is coupled to comparator C 3 723 , which then compares the delayed PN code to the received signal 703 . This process can proceed through a number of stages, e.g. M, which successively delay the PN code. In the last stage the delayed PN code 729 will have M delays 727 inserted and will be compared with the received signal 703 in the M+1 correlator 731 and will produce the M+1 output 733 . The output which has the highest value is the stage which has achieved the best synchronization between the PN code and the received signal. In addition the mechanism of FIG. 7 can be used to determine interference levels. If the output of all the stages are high, then there is strong interference and a strong signal is present. As one skilled in the art will recognize, there are a variety of different variations of the multiple comparator scheme which may be used. The number of delays may be increased or decreased, the time of each delay may change, the PN code may be advanced as well as delayed, the received signal may also be delayed, and other variations are possible. Systems containing CDMA or spread spectrum components may employ various methods of hypothesis testing for signal acquisition and PN code identification. Hypothesis testing can prevent correct PN codes from being rejected based on a transiently interfering signal, and can prevent an incorrect PN code, from being accepted because of a transient interference. Hypothesis testing can also allow marginal signals to be decoded due to the successive attempt nature of the method. The method has drawbacks however. For example if a signal is low, because of overhead foliage for instance, identifying the proper code and acquiring the signal can take a significant amount of time because of the successive threshold tests which must be passed which can also take a significant amount of time. Hypothesis testing can also degrade performance under strong signal conditions. If a signal is strong and the direct path between the signal source and the receiving unit is blocked, the receiving unit may acquire a reflection of the signal. Such a reflected signal is commonly referred to as a multipath signal, because, in addition to the direct path of the signal to the receiver, there is another indirect path from the transmitter to the receiver. In a phone unit that contains a comparator such as that in FIG. 7, this can lead to an incorrect delay being identified as corresponding to the proper timing between the received signal and the PN code, if a correlator synchronizing schemes, such as illustrated in FIG. 7, is employed . In such a case, the improper timing can continue when multipath signal fades and the resulting phone connection may be degraded. Multipath signals are so common a problem that in some systems, for example the IS-95 standard, the multipath signals are decoded to enhance the performance of the receiver. In an application, such as a GPS receiver, locking on to a multipath signal, may cause the GPS unit to exhibit an incorrect position due to the additional time a multipath signal takes to travel from the source satellite to the receiver. The unit may interpret this additional time as additional distance from the signal source. The threshold levels within the hypothesis testing determine how much of a problem each of these phenomena are. If the threshold levels are higher in the hypothesis testing, then the difficulty with multipath signals tends to be minimized because multipath signals tend to be weaker than directly propagated signals and, thus, higher hypothesis testing threshold levels will tend to reject the weaker multipath signals. Conversely, under weak signal conditions, the lowering of hypothesis testing threshold levels will tend to speed the acquisition of the signal and the determination of the correct PN code because the correlator outputs, on average, will be less with weak signals. Hypothesis testing threshold levels reflect a particular compromise between these two extremes to be effective. In one aspect of the invention, different embodiments compensate for these two opposing requirements by adjusting the threshold values within the hypothesis testing mechanism. It should be noted that the phrase “adjusting threshold values” can have more meaning than merely adjusting the actual level of the threshold values. As one skilled in the art will appreciate, the phrase “adjusting threshold values”, in addition to meaning adjustment of the actual level of the threshold values, it can also mean: eliminating a series of threshold values, adding a series of threshold values to the values being used, changing the number of times a signal must be found to exceed the threshold in order to pass on to the next threshold, changing the magnitude between threshold values, or other methods which alter the characteristics of the hypothesis testing. Several embodiments of the invention will be described in order to illustrate a variety of possible implementations. These examples are for illustrative purposes only, and many other variations of the invention may be implemented without departing from the spirit of the invention or the inventive concept embodied therein. FIG. 8 is a block diagram of detailed representation of a preferred embodiment of an example GPS receiver system 801 , for decoding of signals from multiple satellites. The GPS receiver receives the satellite signals through an antenna 803 . A demodulator 807 mixes the signal with a carrier frequency 805 and the resultant signal 808 is reduced to base band frequencies. The resultant signal 808 is a composite of all the satellite signals that the GPS receiver unit receives. To decode an individual satellites data stream the composite signal 808 must be correlated with the correct PN code. If the composite signal is correlated with an incorrect code, no data will be decoded. There are 32 PN codes that are designated by the GPS authority for use within the GPS system. Twenty four of these PN codes will be used by active satellites for the purpose of encoding their data. Each of the 24 active satellites in the GPS system has its own individual PN code. A GPS receiver must extract data from several satellites in order to determine the position of the receiver, and it must extract data from the satellites simultaneously. This situation is represented in the example embodiment shown in FIG. 8 . In the embodiment shown the GPS receiver unit represented can extract data from 12 satellites simultaneously. Codes are obtained from the code table 817 which contains all 32 GPS PN spreading codes, sometimes these codes are referred to as GPS' “Gold” codes. “Gold Codes” are obtained by adding two PN sequences with different phase shifts. PN coded #1, 815 , which has been obtained from the code table 817 is used in the correlator 809 to extract the data from the signal. The resulting data is then decoded in the data decoder 811 . The output 813 of the data decoder 811 contains information from the satellite, which can then be used to ascertain the distance of the satellite from the receiver. A second correlating and data decoding unit 819 is illustrated similar to the first. The second unit takes a second PN code 825 and multiplies it with the incoming signal in the correlator 821 to despread it. The data thus despread is decoded in the data decoder 823 , the output of which 827 is used to ascertain the distance of the satellite from the receiver. There are 12 such units in the present example embodiment. At least four satellite signals are necessary to be certain that a location point can be triangulated and the position of the receiver determined. Having more than four signals can increase the accuracy of the position fix. A GPS receiver on earth can receive signals from at most 11 satellites at one time. This leaves one spare correlating and data decoding unit. In one embodiment of the invention this spare despreading and data decoding unit will be used with the 25th satellite code, which is guaranteed by the GPS authority never to be in any satellite. The embodiment of the invention which uses the 25th satellite code correlates it with the incoming spread spectrum signal. Because there is guaranteed to be no signal using the 25th code, and because this embodiment has at least one spare correlator unit the 25th code can be continually correlated with the spread spectrum signal being received. The output of this correlation should ideally be a constant −1. In the real world, however this output will many times differ from −1. This difference is caused by interference and noise present in the signal. With no code modulation present the output of this correlator will then be a function of the signal strength, and the output of this correlator can then be used to determine the signal strength. Knowing the signal strength, the threshold values of the hypothesis testing portion of the circuit can then be modified to give better results. In high signal conditions, the values of the thresholds within the hypothesis tester can be increased in order to reduce the likeliness that a multipath signal may be acquired. Modified hypothesis testing can reduce the acquisition time in the reduced signal environment by reducing the hypothesis testing thresholds. Portable phones do not have a code similar to the 25th GPS code which is dedicated to being unused in any unit. There is no such guaranteed unused code which can be used for the purpose of determining the signal strength. A PN code however could be so designated. In lieu of a dedicated unused code, phones can use a code that is currently not in use. They can be programmed with several codes. The phones correlator can then search for signals using these codes. If two codes which have no detectable signal present show the 'same non −1 correlated output, then it can be assumed that those codes are not being used and the values out of the correlators can be used to determine the signal strength. This embodiment is illustrated in FIG. 9 . FIG. 9 is a block diagram of an example embodiment of modified hypothesis testing incorporated into a spread spectrum receiver system. A preferred embodiment of a signal acquisition unit 901 which be incorporated into a portable CDMA phone, CDMA phone base station, or a GPS receiver. It might alternatively be incorporated in its present or a changed form into other systems which use spread spectrum technology. The function of the signal acquisition unit in this embodiment is to determine whether a signal with a particular code is present. The spread spectrum signal 903 is coupled to both correlator 909 and correlator 907 . Correlator 909 is used to correlate the signal with a code 911 that is not being used to encode a signal, i.e. an unused code. The output of this correlation step is then coupled to the computational unit 913 which computes a value for signal strength and then further uses this computed value of signal strength to modify the threshold values in the modified hypothesis tester 915 . The incoming spread spectrum signal 903 is also coupled to the correlator 907 . Code X, which is the PN code 905 , that the unit is attempting to acquire, is coupled to the correlator 907 . The output of the correlator 907 is coupled to the modified hypothesis tester 915 , which will provide a signal 917 , if it finds that the signal containing code X is present, and will provide signal 919 , if signal containing code X is not present. The modified hypothesis testing can identify whether a signal using code X as a spreading code is present (acquire the signal) and can also decide that a signal is not present faster than a non modified hypothesis testing system. This can be especially useful in spread spectrum cordless phones of the type that are used within homes. Those phones must search for an empty code to use every time a call is made or answered, and it is important that the search time for a code be as brief as possible. Some GPS receivers employ active antennas to boost the reception of the GPS signals. One of the advantages of embodiments of the present invention, is that their increased sensitivity may allow the use of much less expensive passive type antennae. This increase in signal acquisition sensitivity opens the possibility of reduced cost units with passive antennae. The increase in signal acquisition sensitivity also enables embodiments in which an active antenna is switched in and out of the circuit. This type of implementation may be used to increase the sensitivity by employing modified hypothesis testing in the case where an active antenna is still used. A preferred embodiment where an active antenna is switched in and out of the circuit is illustrated in FIG. 10 . FIG. 10 depicts an antenna switching scheme in a GPS receiver according to an example embodiment. The 25th satellite PN code 1003 , which is not present in any satellite, is combined with an incoming signal 1005 in a correlator 1007 . The output of the correlator 1007 is proportional to the signal strength of the incoming signal. The output 1009 is coupled to a comparator 1011 . The result of the comparison 1013 , is then provided to switches 1017 and 1019 in such a fashion that, when the signal is low, the active antenna 1015 is switched into the circuit, and when the signal strength is high, the antenna is switched out of the circuit. This type of arrangement has several benefits. One benefit of the switched antenna arrangement is that modified hypothesis testing decreases the time necessary to determine whether the signal is present or not. It also enables weaker signals to be acquired than could be acquired without the system. The signal strength determination and antenna switching not only speeds the acquisition of weak signals and enables the acquisition of signals that could not otherwise be acquired, in addition the switching out of the active antenna in high signal conditions combined with the modified hypothesis testing will minimize the problem of multipath signals being acquired. The above specification and examples provide a complete description of the, invention which will enable one skilled in the art to practice it. It also provides the best known mode of practicing the invention. One skilled in the art will recognize that the ideas embodied in this invention may be combined and modified in a multitude of ways. Since many embodiments of the invention can be made without departing from the spirit and scope of the invention, the invention resides in the claims hereinafter appended.

Embodiments of the invention are used to improve performance of spread spectrum communications equipment. The improvement may take the form of improved sensitivity to weak signals, quicker acquisition time of weak signals, or the reduction of multipath interference. To acquire a spread spectrum signal PN codes are commonly compared with the spread spectrum signal. This comparison is often in reality a successive series of comparisons with the same code. Successive comparisons are often carried out in a process called hypothesis testing by which the correlated output of the spread spectrum signal and the PN code must pass a series of thresholds. This method is adopted to prevent identifying a PN code as being present based on a spurious correlation value. This method of successive comparisons also prevents a low correlated value from being rejected immediately thereby helping assure that signals with low signal strength can be identified also. By adjusting the series of comparison levels within the hypothesis tester depending on the signal strength weak signals can be identified quicker and easier, multipath signals can be rejected better, and amplification devises such as active antennas can be switched on and off.

CONTINUING DATA This application is a 371 of PCT/EP2013/001352 filed May 7, 2013 which claims benefit of 61/653,037 filed May 30, 2012. FIELD OF THE INVENTION The invention relates to solid state forms of N—((S)-2,3-Dihydroxy-propyl)-3-(2-fluoro-4-iodo-phenylamino)-isonicotinamide, processes for their preparation, and medical uses thereof. SUMMARY OF THE RELATED ART N—((S)-2,3-Dihydroxy-propyl)-3-(2-fluoro-4-iodo-phenylamino)-isonicotinamide, for ease of reference hereinafter referred to as Compound C, its use as a kinase inhibitor to treat cancer, and its manufacture is disclosed in WO 2006/045514, page 76, Example 115. However, no solid state form of Compound C is disclosed in WO 2006/045514, or has been otherwise publicly disclosed to the best of applicants' knowledge, until the present date. Without a solid state form, however, it is not possible to provide a pharmaceutical active ingredient in a tablet, which is the dosage form of choice in terms of manufacturing, packaging, stability and patient compliance. Therefore, in order to advance the development of Compound C as a drug substance, there is a high need to provide at least one solid state form of this compound. DESCRIPTION OF THE INVENTION Surprisingly, the inventors of the present patent application for the first time succeeded to provide a number of solid state forms of C that are not only crystalline but also stable, i.e. do not convert to other forms under the conditions of tablet manufacturing and storage. In one specific aspect the invention relates to crystalline forms A1 and A2 of the mono hydrochloride of C. In another specific aspect the invention relates to crystalline forms B1 and B2 of the free base of C. The crystalline forms are characterized, e.g., by x-ray powder diffractometry, single crystal diffractometry, FT IR spectroscopy, FT Raman spectroscopy, differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA) as hereinafter shown in the experimental section. All forms are characterized by high crystallinity, absence of hygroscopicity and high thermal stability. Moreover, forms A1 and A2 show a higher solubility and faster dissolution kinetics as compared to forms B1 and B2. Furthermore, the present invention relates to pharmaceutical compositions comprising a solid state form of the present invention, together with at least one pharmaceutically acceptable carrier. “Pharmaceutical composition” means one or more active ingredients, and one or more inert ingredients that make up the carrier, as well as any product which results, directly or indirectly, from combination, complexation or aggregation of any two or more of the ingredients, or from dissociation of one or more of the ingredients, or from other types of reactions or interactions of one or more of the ingredients. Accordingly, the pharmaceutical compositions of the present invention encompass any composition made by admixing a compound of the present invention and a pharmaceutically acceptable carrier. A pharmaceutical composition of the present invention may additionally comprise one or more other compounds as pharmaceutical active ingredients. The pharmaceutical compositions include compositions suitable for oral, rectal, topical, parenteral (including subcutaneous, intramuscular, and intravenous), ocular (ophthalmic), pulmonary (nasal or buccal inhalation), or nasal administration, although the most suitable route in any given case will depend on the nature and severity of the conditions being treated and on the nature of the active ingredient. They may be conveniently presented in unit dosage form and prepared by any of the methods well-known in the art of pharmacy. In one embodiment, said compounds and pharmaceutical composition are for the treatment of cancer such as brain, lung, including non-small cell lung cancer, colon, colorectal, epidermoid, squamous cell, bladder, gastric, pancreatic, breast, head & neck, renal, kidney, liver, ovarian, prostate, uterine, oesophageal, testicular, gynecological, including endometrial, thyroid cancer, melanoma, including NRAS or BRAF mutated melanoma, as well as hematologic malignancies such as acute myelogenous leukemia, multiple myeloma, chronic myelogneous leukemia, myeloid cell leukemia, Kaposi's sarcoma, or any other type of solid or liquid tumors. Preferably, the cancer to be treated is chosen from colon, lung, breast and hematological tumor types. Therefore, the present invention relates also to the use of the herein disclosed solid state forms of Compound C for the treatment of the above mentioned diseases. The anti-cancer treatment defined above may be applied as a monotherapy or may involve, in addition to the herein disclosed solid state forms of Compound C, conventional surgery or radiotherapy or medicinal therapy. Such medicinal therapy, e.g. a chemotherapy or a targeted therapy, may include one or more, but preferably one, of the following anti-tumor agents: Alkylating Agents Such as altretamine, bendamustine, busulfan, carmustine, chlorambucil, chlormethine, cyclophosphamide, dacarbazine, ifosfamide, improsulfan tosilate, lomustine, melphalan, mitobronitol, mitolactol, nimustine, ranimustine, temozolomide, thiotepa, treosulfan, mechloretamine, carboquone, apaziquone, fotemustine, glufosfamide, palifosfamide, pipobroman, trofosfamide, uramustine; Platinum Compounds Such as carboplatin, cisplatin, eptaplatin, miriplatine hydrate, oxaliplatin, lobaplatin, nedaplatin, picoplatin, satraplatin; DNA Altering Agents Such as amrubicin, bisantrene, decitabine, mitoxantrone, procarbazine, trabectedin, clofarabine, amsacrin, brostallicin, pixantrone, laromustine; Topoisomerase Inhibitors Such as etoposide, irinotecan, razoxane, sobuzoxane, teniposide, topotecan, amonafide, belotecan, elliptinium acetate, voreloxin; Microtubule Modifiers Such as cabazitaxel, docetaxel, eribulin, ixabepilone, paclitaxel, vinblastine, vincristine, vinorelbine, vindesine, vinflunine, fosbretabulin, tesetaxel: Antimetabolites Such as asparaginase, azacitidine, calcium levofolinate, capecitabine, cladribine, cytarabine, enocitabine, floxuridine, fludarabine, fluorouracil, gemcitabine, mercaptopurine, methotrexate, nelarabine, pemetrexed, pralatrexate, azathioprine, thioguanine, carmofur, doxifluridine, elacytarabine, raltitrexed, sapacitabine, tegafur, trimetrexate; Anticancer Antibiotics Such as bleomycin, dactinomycin, doxorubicin, epirubicin, idarubicin, levamisole, miltefosine, mitomycin C, romidepsin, streptozocin, valrubicin, zinostatin, zorubicin, daunurobicin, plicamycin, aclarubicin, peplomycin, pirarubicin; Hormones/Antagonists Such as abarelix, abiraterone, bicalutamide, buserelin, calusterone, chlorotrianisene, degarelix, dexamethasone, estradiol, fluocortolone, fluoxymesterone, flutamide, fulvestrant, goserelin, histrelin, leuprorelin, megestrol, mitotane, nafarelin, nandrolone, nilutamide, octreotide, prednisolone, raloxifene, tamoxifen, thyrotropin alfa, toremifene, trilostane, triptorelin, diethylstilbestrol, acolbifene, danazol, deslorelin, epitiostanol, orteronel, enzalutamide; Aromatase Inhibitors Such as aminoglutethimide, anastrozole, exemestane, fadrozole, letrozole, testolactone, formestane; Small Molecule Kinase Inhibitors Such as crizotinib, dasatinib, erlotinib, imatinib, lapatinib, nilotinib, pazopanib, regorafenib, ruxolitinib, sorafenib, sunitinib, vandetanib, vemurafenib, bosutinib, gefitinib, axitinib, afatinib, alisertib, dabrafenib, dacomitinib, dinaciclib, dovitinib, enzastaurin, nintedanib, lenvatinib, linifanib, linsitinib, masitinib, midostaurin, motesanib, neratinib, orantinib, perifosine, ponatinib, radotinib, rigosertib, tipifarnib, tivantinib, tivozanib, trametinib, pimasertib, brivanib alaninate, cediranib, apatinib, cabozantinib S-malate, carfilzomib, ibrutinib, icotinib; Photosensitizers Such as Methoxsalen, porfimer sodium, talaporfin, temoporfin; Antibodies Such as alemtuzumab, besilesomab, brentuximab vedotin, cetuximab, denosumab, ipilimumab, ofatumumab, panitumumab, rituximab, tositumomab, trastuzumab, bevacizumab, catumaxomab, elotuzumab, epratuzumab, farletuzumab, mogamulizumab, necitumumab, nimotuzumab, obinutuzumab, ocaratuzumab, oregovomab, ramucirumab, rilotumumab, siltuximab, tocilizumab, zalutumumab, zanolimumab, matuzumab, dalotuzumab, onartuzumab, pertuzumab, racotumomab, tabalumab; Cytokines Such as aldesleukin, interferon alfa, interferon alfa2a, interferon alfa2b, tasonermin, teceleukin, oprelvekin; Drug Conjugates Such as denileukin diftitox, ibritumomab tiuxetan, iobenguane I123, prednimustine, trastuzumab emtansine, estramustine, gemtuzumab ozogamicin, aflibercept, cintredekin besudotox, edotreotide, inotuzumab ozogamicin, naptumomab estafenatox, oportuzumab monatox, technetium (99mTc) arcitumomab, vintafolide; Vaccines Such as sipuleucel, vitespen, emepepimut-S, oncoVAX, rindopepimut, troVax, stimuvax; Miscellaneous alitretinoin, bexarotene, bortezomib, everolimus, ibandronic acid, imiquimod, lenalidomide, lentinan, metirosine, mifamurtide, pamidronic acid, pegaspargase, pentostatin, sipuleucel, sizofiran, tamibarotene, temsirolimus, thalidomide, tretinoin, vismodegib, zoledronic acid, thalidomide, vorinostat, celecoxib, cilengitide, entinostat, etanidazole, ganetespib, idronoxil, iniparib, ixazomib, lonidamine, nimorazole, panobinostat, peretinoin, plitidepsin, pomalidomide, procodazol, ridaforolimus, tasquinimod, telotristat, thymalfasin, tirapazamine, tosedostat, trabedersen, ubenimex, valspodar, gendicine, picibanil, reolysin, retaspimycin hydrochloride, trebananib, virulizin. In practical use, the compounds of the present invention can be combined as the active ingredient in intimate admixture with a pharmaceutical carrier according to conventional pharmaceutical compounding techniques. The carrier may take a wide variety of forms depending on the form of preparation desired for administration, e.g., oral or parenteral (including intravenous). In preparing the compositions for oral dosage form, any of the usual pharmaceutical media may be employed, such as, for example, water, glycols, oils, alcohols, flavoring agents, preservatives, coloring agents and the like. In the case of oral liquid preparations, any of the usual pharmaceutical media may be employed, such as, for example, suspensions, elixirs and solutions; or carriers such as starches, sugars, microcrystalline cellulose, diluents, granulating agents, lubricants, binders, disintegrating agents and the like. In the case of oral solid preparations the composition may take forms such as, for example, powders, hard and soft capsules and tablets, with the solid oral preparations being preferred over the liquid preparations. Because of their ease of administration, tablets and capsules represent the most advantageous oral dosage unit form in which case solid pharmaceutical carriers are obviously employed. If desired, tablets may be coated by standard aqueous or nonaqueous techniques. Such compositions and preparations should contain at least 0.1 percent of active compound. The percentage of active compound in these compositions may, of course, be varied and may conveniently be between about 2 percent to about 60 percent of the weight of the unit. The amount of active compound in such therapeutically useful compositions is such that an effective dosage will be obtained. The active compounds can also be administered intranasally as, for example, liquid drops or spray. The tablets, pills, capsules, and the like may also contain a binder such as gum tragacanth, acacia, corn starch or gelatin; excipients such as dicalcium phosphate; a disintegrating agent such as corn starch, potato starch, alginic acid; a lubricant such as magnesium stearate; and a sweetening agent such as sucrose, lactose or saccharin. When a dosage unit form is a capsule, it may contain, in addition to materials of the above type, a liquid carrier such as a fatty oil. Various other materials may be present as coatings or to modify the physical form of the dosage unit. For instance, tablets may be coated with shellac, sugar or both. A syrup or elixir may contain, in addition to the active ingredient, sucrose as a sweetening agent, methyl and propylparabens as preservatives, a dye and a flavoring such as cherry or orange flavor. Compounds of the present invention may also be administered parenterally. Solutions or suspensions of these active compounds can be prepared in water suitably mixed with a surfactant such as hydroxy-propylcellulose. Dispersions can also be prepared in glycerol, liquid polyethylene glycols and mixtures thereof in oils. Under ordinary conditions of storage and use, these preparations contain a preservative to prevent the growth of microorganisms. The pharmaceutical forms suitable for injectable use include sterile aqueous solutions or dispersions and sterile powders for the extemporaneous preparation of sterile injectable solutions or dispersions. In all cases, the form must be sterile and must be fluid to the extent that easy syringability exists. It must be stable under the conditions of manufacture and storage and must be preserved against the contaminating action of microorganisms such as bacteria and fungi. The carrier can be a solvent or dispersion medium containing, for example, water, ethanol, polyol (e.g., glycerol, propylene glycol and liquid polyethylene glycol), suitable mixtures thereof, and vegetable oils. Any suitable route of administration may be employed for providing a mammal, especially a human, with an effective dose of a compound of the present invention. For example, oral, rectal, topical, parenteral, ocular, pulmonary, nasal, and the like may be employed. Dosage forms include tablets, troches, dispersions, suspensions, solutions, capsules, creams, ointments, aerosols, and the like. Preferably compounds of the present invention are administered orally. The effective dosage of active ingredient employed may vary depending on the particular compound employed, the mode of administration, the condition being treated and the severity of the condition being treated. Such dosage may be ascertained readily by a person skilled in the art. When treating inflammatory, degenerative or hyperproliferative diseases for which compounds of the present invention are indicated, generally satisfactory results are obtained when the compounds of the present invention are administered at a daily dosage of from about 0.01 milligram to about 100 milligram per kilogram of body weight, preferably given as a single daily dose. For most large mammals, the total daily dosage is from about 0.1 milligrams to about 1000 milligrams, preferably from about 0.2 milligram to about 50 milligrams. In the case of a 70 kg adult human, the total daily dose will generally be from about 0.2 milligrams to about 200 milligrams. This dosage regimen may be adjusted to provide the optimal therapeutic response. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 : Powder X-ray diffractogram of Form A1 FIG. 2 : Single crystal structure of Form A1 FIG. 3 : FTIR spectrum of Form A1 FIG. 4 : FT Raman spectrum of Form A1 FIG. 5 : DSC scan of Form A1 FIG. 6 : TGA scan of Form A1 FIG. 7 : Water Vapour Sorption Isotherm (25° C.) of Form A1 FIG. 8 : Powder X-ray diffractogram of Form A2 FIG. 9 : Crystal structure of Form A2 (calculated from Powder data) FIG. 10 : FTIR spectrum of Form A2 FIG. 11 : FT Raman spectrum of Form A2 FIG. 12 : DSC scan of Form A2 FIG. 13 : TGA scan of Form A2 FIG. 14 : Water Vapour Sorption Isotherm (25° C.) of Form A2 FIG. 15 : Powder X-ray diffractogram of Form A-NF3 FIG. 16 : Powder X-ray diffractogram of Form A-NF6 FIG. 17 : Powder X-ray diffractogram of Form A-NF9 FIG. 18 : Powder X-ray diffractogram of Form A-NF10 FIG. 19 : Powder X-ray diffractogram of Form A-NF11 FIG. 20 : Powder X-ray diffractogram of Form B1 FIG. 21 : Crystal structure of Form B1 (calculated from Powder data) FIG. 22 : FTIR spectrum of Form B1 FIG. 23 : FT Raman spectrum of Form B1 FIG. 24 : DSC scan of Form B1 FIG. 25 : TGA scan of Form B1 FIG. 26 : Water Vapour Sorption Isotherm (25° C.) of Form B1 FIG. 27 : Powder X-ray diffractogram of Form B2 FIG. 28 : Crystal structure of Form A2 (calculated from Powder data) FIG. 29 : FTIR spectrum of Form B2 FIG. 30 : FT Raman spectrum of Form B2 FIG. 31 : DSC scan of Form B2 (Morphological Type 1) FIG. 32 : TGA scan of Form B2 (Morphological Type 1) FIG. 33 : DSC scan of Form B2 (Morphological Type 2) FIG. 34 : TGA scan of Form B2 (Morphological Type 2) FIG. 35 : Water Vapour Sorption Isotherm (25° C.) of Form B2 FIG. 36 : Powder X-ray diffractogram of Form B-S1 FIG. 37 : Powder X-ray diffractogram of Form B-S2 FIG. 38 : Dissolution of Compound C solid state forms at pH 1.2 FIG. 39 : Dissolution of Compound C solid state forms at pH 3.0 FIG. 40 : Dissolution of Compound C solid state forms at pH 5.0 FIG. 41 : Dissolution of Compound C solid state forms at pH 6.8 ABBREVIATIONS Some abbreviations that may appear in this application are as follows: Designation API Active Pharmaceutical Ingredient DI Deionized DMF Dimethylformamide DMSO Dimethyl Sulfoxide DSC Differential Scanning Calorimetry FTIR Fourier Transform Infrared Spectroscopy h Hour HPLC High Pressure Liquid Chromatography M Molar (unit of concentration) MTBE Methyl tertiary-butyl ether N Normal (unit of concentration) NMP N-methylpyrrolidone PBS Phosphate Buffered Saline PTFE Polytetrafluoroethylene RT Room Temperature (~23° C.) TGA Thermogravimetric Analysis THF Tetrahydrofurane USP U.S. Pharmacopeia EXAMPLES The working examples presented below are intended to illustrate particular embodiments of the invention, and are not intended to limit the scope of the specification or the claims in any way. By mono hydrochloride form is meant a stoichiometric ratio of Compound C to HCl between 0.8:1 and 1.2:1, preferably between 0.9:1 and 1.1:1. Most preferred is a ratio of 1:1. 1. Mono-Hydrochloride Form A1 1.1 Characterization of Form A1 1.1.1 X-Ray Powder Diffractometry A powder X-ray Diffraction pattern of Form A1 was obtained by standard techniques at RT as described in the European Pharmacopeia 6 th Edition chapter 2.9.33, which is shown in FIG. 1 . A list of characteristic X-ray peaks derived from this pattern is provided in Table I: °2θ (Cu-Kα 1 No. radiation) ± 0.2° 1  5.5 2 15.9 3 16.8 4 18.5 5 19.1 6 19.5 7 20.1 8 21.1 9 22.6 10 23.0 11 24.4 12 24.9 13 25.2 14 25.7 15 27.1 16 28.4 17 29.2 18 29.6 The most significant X-ray peaks from Table I are listed in Table II: °2θ (Cu-Kα 1 No. radiation) ± 0.2° 1  5.5 2 16.8 3 18.5 4 19.1 5 22.6 6 23.0 7 24.9 8 25.2 9 28.4 10 29.2 Broken down by sample orientation, the most characteristic peaks are as listed in Tables III, IV and V: TABLE III 0kl orientation °2θ (Cu-Kα 1 No. radiation) ± 0.2° 1 5.5 2 16.8 3 19.5 4 23.0 TABLE IV h0l orientation °2θ (Cu-Kα 1 No. radiation) ± 0.2° 1  5.5 2 18.5 3 19.1 4 28.4 5 29.6 TABLE V hk0 orientation °2θ (Cu-Kα 1 No. radiation) ± 0.2° 1 15.9 2 19.1 3 24.9 Therefore, in a preferred aspect the present invention relates to crystalline form A1 having characteristic peaks at the 2θ angles provided in Table I. In a more preferred aspect the invention relates to form A1 having characteristic peaks at the 2θ angles provided in Table II. In an equally preferred aspect the invention relates to form A1 having characteristic peaks at the 2θ angles provided in one or more of Tables III, IV and V. 1.1.2 X-Ray Singe Crystal Diffractometry In addition, single crystal X-ray structure data were obtained on Form A1, from which the spacial arrangement of the A molecules in the crystal was computed as shown in FIG. 2 . Form A1 crystallises in the chiral monoclinic space group P2 1 with the lattice parameters a=9.6±0.1 Å, b=11.2±0.1 Å, c=16.6±0.1 Å, and β=104.4±0.5° (α=γ=90°). From the single crystal structure it is obvious that Form A1 represents an anhydrous form. In a specific aspect, the invention relates to a crystalline form of the mono hydrochloride of Compound C characterized by these crystallographic parameters. 1.1.3 Vibrational Spectroscopy Form A1 can be further characterized by infrared and Raman-spectroscopy. FT-Raman and FT-IR spectra were obtained by standard techniques as described in the European Pharmacopeia 6 th Edition chapter 2.02.24 and 2.02.48. For measurement of the FT-IR and FT-Raman-spectra a Bruker Vector 22 and a Bruker RFS 100 spectrometer were used. FT-IR spectra and FT-Raman spectra were base-line corrected using Bruker OPUS software. An FT-IR spectrum was obtained using a KBr pellet as sample preparation technique. The FT-IR spectrum is shown in FIG. 3 from which band positions were derived as given below. Form A1 IR band positions (±2 cm −1 , relative intensity*) 3108 cm −1 (m), 2935 cm −1 (m), 2772 cm −1 (m), 1655 cm −1 (s), 1539 cm −1 (s), 1493 cm −1 (s), 1380 cm −1 (m), 1269 cm −1 (s), 1118 cm −1 (m), 1036 cm −1 (m), 808 cm −1 (m), 773 cm −1 (m) *“s”=strong (transmittance≦50%), “m”=medium (50%<transmittance≦70%), “w”=weak (transmittance>70%) An FT-Raman spectrum is shown in FIG. 4 from which band positions were derived as given below: Form A1 Raman band positions (±2 cm −1 , relative intensity*): 3065 cm −1 (w), 1628 cm −1 (m), 1599 cm −1 (s), 1503 cm −1 (m), 1319 cm −1 (m), 1267 cm −1 (m), 1230 cm −1 (m), 1089 cm −1 (m) *“s”=strong (relative Raman intensity≧0.2), “m”=medium (0.2>relative Raman intensity≧0.1), “w”=weak (relative Raman intensity<0.1) 1.1.4 Other Analytical Methods It could be shown that Form A1 is a crystalline anhydrous form, which is further characterised by the following physical properties: Ion Chromatography revealed a chloride content of approx. 7.9 wt % CI, which is equivalent to a molar acid:base ratio of 1.05:1. Thermal behaviour of Form A1 shows an overlapped melting/decomposition processes>160° C., with no significant weight loss up to this temperature. DSC and TGA profiles are shown in FIGS. 5 and 6 . The DSC scan of Form A1 was acquired on a Mettler-Toledo DSC 821 with a heating rate of 5 K/min, using nitrogen purge gas at 50 mL/min. The TGA scan of Form A1 was acquired on a Perkin-Elmer Pyris TGA 1 with a heating rate of 5 K/min, using nitrogen purge gas at 50 mL/min. Water Vapour Sorption behaviour shows insignificant water uptake levels<0.1 wt % in the entire relative humidity range 0-98% RH. Form A1 can be classified as non-hygroscopic according to Ph. Eur. Criteria (section 5.11.). A Water Vapor Sorption isotherm (25° C.) of Form A1 is shown in FIG. 7 , which was acquired on a DVS-1 System from SMS. Solubility of Form A1 in DI Water at 37° C. was determined to be approx. 2.8 mg/mL, solubility of Form A1 at 37° C. in 0.1. N HCl at 37° C. was determined to be approx. 44 mg/mL (see Example 9). Active Pharmaceutical Ingredient dissolution studies with Form A1 in various buffer systems at 37° C. revealed rapid and complete dissolution in the pH range 1.2 to 6.8 (see Example 10). Overall, Form A1 reveals very good solid-state properties (very good crystallinity, non-hygroscopic, sufficient thermal stability) with significantly improved aqueous solubility compared to the free base (see Example 9). 1.2 Processes for the Preparation of A1 General reaction scheme to obtain acetonide-protected C: Reaction scheme to obtain HCl salt Form A1 from acetonide-protected C: 1.2.1 Method 1 A solution of acetonide-protected Compound C as free base (1.0 wt) in methanol (20.0 vol) was clarified through a 0.7 μm glass microfibre filter paper. Clarified ca. 2 M hydrochloric acid in diethyl ether (5.3 vol) was added to the methanolic solution at 16 to 25° C. The mixture was stirred for 60 to 90 minutes at 16 to 25° C. and filtered. The filter-cake was washed with a clarified mixture of methanol/diethyl ether 4:1 (1.0 vol) and pulled dry on the pad for 60 to 90 minutes. The filter-cake was transferred to a suitable vessel and clarified propan-2-ol (20.0 vol) and clarified water (1.0 vol) was charged. The mixture was heated to and stirred at 75 to 85° C. for 30 to 50 minutes. The mixture was cooled to 0 to 5° C. over 60 to 90 minutes and aged at 0 to 5° C. for 20 to 30 minutes and filtered. The filter-cake was washed with clarified propan-2-ol (1.0 vol) and pulled dry on the filter under nitrogen for up to 24 hours to give a pre-blend of Compound C hydrochloride. A mixture of the pre-blend Form A1 (1.0 wt %) and propan-2-ol (3.0 vol) was charged to a suitable flask and stirred for 60 to 90 minutes at 16 to 25° C. The mixture was filtered and the filter-cake was washed with propan-2-ol (1.0 vol) and pulled dry on the filter under nitrogen for up to 24 hours. The filter-cake was transferred to drying trays and dried under vacuum at up to 40° C. until the propan-2-ol content was 0.2 wt % to give Form A1. 1.2.2 Method 2 Approx. 800 g of Form A2 (see Example 2) were dispersed in 16 L 2-Propanol and 0.8 L Water, and heated to 80° C. The reaction mixture was kept at 80° C. for 3 hours, and slowly cooled down to room temperature. The dispersion was then kept at room temperature for 3 hours, and then further cooled down to 0° C. The dispersion was then filtered, and the obtained filter residue was dried at 40° C. under vacuum overnight. 1.2.3 Method 3 Approx. 25 mg of Compound C mono hydrochloride were dispersed in 0.3 mL DMF, and heated to 50° C. The resulting solution was then cooled to RT in approx. 1 h, resulting in yellow crystals. 2. Mono-Hydrochloride Form A2 2.1 Characterization of Form A2 2.1.1 X-Ray Powder Diffractometry A Powder X-Ray Diffraction pattern of Form A2 was obtained by standard techniques at RT as described in the European Pharmacopeia 6 th Edition chapter 2.9.33, which is shown in FIG. 8 . A list of characteristic X-ray peaks derived from this pattern is provided in Table VI: °2θ (Cu-Kα 1 No. radiation) ± 0.2° 1  5.4 2  9.6 3 11.3 4 13.5 5 16.0 6 16.4 7 16.7 8 17.8 9 18.4 10 18.6 11 19.2 12 20.2 13 20.9 14 21.6 15 22.9 16 23.3 17 23.9 18 24.4 19 25.0 20 26.0 21 26.7 22 27.5 23 27.9 The most significant X-ray peaks from Table VI are listed in Table VII: °2θ (Cu-Kα 1 No. radiation) ± 0.2° 1  5.4 2  9.6 3 18.4 4 18.6 5 20.9 6 21.6 7 23.9 8 24.4 9 25.0 10 26.0 Broken down by sample orientation, the most characteristic peaks are as listed in Tables VIII, and IX: TABLE VIII h0l orientation °2θ (Cu-Kα 1 No. radiation) ± 0.2° 1 18.4 2 18.6 3 19.2 4 20.2 5 21.6 TABLE IX hk0 orientation No. °2θ (Cu-Kα 1 radiation) ± 0.2° 1 9.6 2 11.3 3 17.8 4 23.9 5 25.0 Therefore, in a preferred aspect the present invention relates to crystalline form A2 having characteristic peaks at the 2θ angles provided in Table VI. In a more preferred aspect the invention relates to form A2 having characteristic peaks at the 2θ angles provided in Table VII. In an equally preferred aspect the invention relates to form A1 having characteristic peaks at the 2θ angles provided in one or more of Tables VIII and IX. X-ray structural data were calculated from powder X-ray data of Form A2 as shown in FIG. 9 . Form A2 crystallises in the chiral orthorhombic space group P2 1 2 1 2 with the lattice parameters (measured at 301 K) a=32.3±0.1 Å, b=11.2±0.1 Å, c=4.8±0.1 Å (α=β=γ=90°). From the crystal structure it is obvious that Form A2 represents an anhydrous form. In a specific aspect, the invention relates to a crystalline form of the mono hydrochloride of Compound C characterized by these crystallographic parameters. 2.1.2 Vibrational Spectroscopy Form A2 can be further characterized by infrared and Raman-spectroscopy. FT-Raman and FT-IR spectra were obtained by standard techniques as described in the European Pharmacopeia 6 th Edition chapter 2.02.24 and 2.02.48. For measurement of the FT-IR and FT-Raman-spectra a Bruker Vector 22 and a Bruker RFS 100 spectrometer were used. FT-IR spectra were base-line corrected using Bruker OPUS software. FT-Raman spectra were vector normalized using the same software. An FT-IR spectrum was obtained using a KBr pellet as sample preparation technique. The FT-IR spectrum is shown in FIG. 10 from which band positions were derived as given below. Form A2 IR band positions (±2 cm −1 , relative intensity*) 3086 cm −1 (s), 2931 cm −1 (s), 2724 cm −1 (s), 1663 cm −1 (s), 1544 cm −1 (s), 1492 cm −1 (s), 1383 cm −1 (s), 1282 cm −1 (s), 1035 cm −1 (s), 810 cm −1 (s), 782 cm −1 (m) *“s”=strong (transmittance≦50%), “m”=medium (50%<transmittance≦70%), “w”=weak (transmittance>70%) An FT-Raman spectrum is shown in FIG. 11 from which band positions were derived as given below: Form A2 Raman band positions (±2 cm −1 , relative intensity*): 3077 cm −1 (w), 1631 cm −1 (s), 1607 cm −1 (s), 1513 cm −1 (m), 1326 cm −1 (m), 1282 cm −1 (s), 1226 cm −1 (m), 1082 cm −1 (w) *“s”=strong (relative Raman intensity≧0.2), “m”=medium (0.2>relative Raman intensity≧0.1), “w”=weak (relative Raman intensity<0.1) 2.1.3 Other Analytical Methods It could be shown that Form A2 is a crystalline anhydrous form, which is further characterised by the following physical properties: Ion Chromatography revealed a chloride content of approx. 7.8 wt % CI, which is equivalent to a molar acid:base ratio of 1.03:1 Thermal behaviour of Form A2 shows an overlapped melting/decomposition processes>160° C., with no significant weight loss up to this temperature. DSC and TGA profiles are shown in FIGS. 12 and 13 . The DSC scan of Form A2 was acquired on a Mettler-Toledo DSC 821 with a heating rate of 5 K/min, using nitrogen purge gas at 50 mL/min. The TGA scan of Form A2 was acquired on a Mettler-Toledo TGA 851 with a heating rate of 5 K/min, using nitrogen purge gas at 50 mL/min. Water Vapour Sorption behaviour shows small water uptake levels only, with a fully reversible adsorption/desorption behaviour. Form A2 can be classified as slightly hygroscopic acc. to Ph. Eur. Criteria (section 5.11.). A Water Vapor Sorption isotherm (25° C.) of Form A2 is shown in FIG. 14 , which was acquired on a DVS-1 System from SMS. Solubility of Form A2 in DI Water at 37° C. was determined to be approx. 2.5 mg/mL, solubility of Form A2 at 37° C. in 0.1. N HCl at 37° C. was determined to >20 mg/mL (see Example 9). Active Pharmaceutical Ingredient dissolution studies with Form A2 in various buffer systems at 37° C. revealed rapid and complete dissolution in the pH range 1.2 to 6.8 (see Example 10). Overall, Form A2 reveals good solid-state properties (good crystallinity, slightly hygroscopic, sufficient thermal stability) with significantly improved aqueous solubility compared to the free base (see Example 9). 2.2 Processes for the Preparation of A2 Reaction scheme to obtain HCl salt Form A2 from acetonide-protected A: 2.2.1 Method 1 Approx. 350 g of acetonide-protected Compound C as free base were dispersed in 7 L dry methanol, and approx. 1.86 L 2 N HCl solution (in diethylether) was added. From the resulting solution a yellow solid precipitated. The reaction mixture was stirred for approx. 4 hours until complete reaction was observed. The dispersion was filtered, washed with diethyl ether, and dried under vacuum for 24 hours. 2.2.2 Method 2 Approx. 145 mg of acetonide-protected Compound C as free base were dispersed in 1.5 mL methanol at RT, and approx. 1.5 mL 1.25 N HCl solution (in methanol) was added at RT. From the resulting solution a yellow solid precipitated. The reaction mixture was stirred for approx. 14 hours before 2 mL of MTBE were added. The dispersion was filtered, washed with MTBE, and dried under vacuum at 40° C. for 4 hours. 2.2.3 Method 3 Approx. 145 mg of acetonide-protected Compound C as free base were dispersed in 1.5 mL methanol at RT, and approx. 1.5 mL 1.25 N HCl solution (in methanol) was added at RT. From the resulting solution a yellow solid precipitated. The reaction mixture was stirred for approx. 6 hours before 2 mL of 2-Propanol were added. The dispersion was filtered, washed with 2-Propanol, and dried under vacuum at 40° C. 2.2.4 Method 4 Approx. 45 mg of Compound C mono hydrochloride were dissolved in 0.5 mL DMSO. The solvent was allowed to evaporate completely at RT, resulting in yellow-orange crystals. 3. Solvates of Compound C Mono Hydrochloride In addition to Forms A1 and A2 described above a series of solvate forms of C mono hydrochloride were also identified, the physical properties of which were not further characterized. 3.1 Dioxane Solvate Form A-NF3 From the powder X-ray diffractogram of Form NF3 shown in FIG. 15 the following peaks were derived—Table X: No. °2θ (Cu-Kα 1 radiation) ± 0.2° 1 4.2 2 8.1 3 14.7 4 16.2 5 17.8 6 18.8 7 19.6 8 20.1 9 20.8 10 21.6 11 22.3 12 22.9 13 23.2 14 24.2 15 25.2 16 25.4 17 30.0 3.2 Acetic Acid Solvate Form A-NF6 From the powder X-ray diffractogram of Form A-NF6 shown in FIG. 16 the following peaks were derived—Table XI: No. °2θ (Cu-Kα 1 radiation) ± 0.2° 1 4.5 2 8.0 3 9.0 4 13.6 5 15.7 6 16.1 7 18.0 8 20.6 9 21.2 10 21.7 11 24.0 12 25.3 13 26.6 14 28.1 15 28.5 16 29.7 17 29.9 3.3 NMP Solvate Form A-NF9 From the powder X-ray diffractogram of Form A-NF9 shown in FIG. 17 the following peaks were derived—Table XII: No. °2θ (Cu-Kα 1 radiation) ± 0.2° 1 4.3 2 8.0 3 8.6 4 10.1 5 11.6 6 15.1 7 16.0 8 19.0 9 20.3 10 21.0 11 21.5 12 23.4 13 24.2 14 24.8 15 25.1 16 25.4 17 25.9 18 27.4 19 29.4 3.4 NMP Solvate Form A-NF10 From the powder X-ray diffractogram of Form A-NF10 shown in FIG. 18 the following peaks were derived—Table XIII: No. °2θ (Cu-Kα 1 radiation) ± 0.2° 1 4.3 2 8.0 3 10.0 4 16.7 5 18.8 6 20.1 7 20.7 8 21.2 9 21.6 10 22.1 11 22.9 12 23.5 13 24.8 14 25.2 15 25.5 16 26.0 17 26.6 3.5 NMP Solvate Form A-NF11 From the powder X-ray diffractogram of Form A-NF11 shown in FIG. 19 the following peaks were derived—Table XIV: No. °2θ (Cu-Kα 1 radiation) ± 0.2° 1 4.3 2 8.0 3 10.1 4 11.6 5 15.2 6 19.0 7 20.3 8 20.6 9 21.0 10 21.5 11 22.0 12 22.4 13 23.5 14 24.3 15 24.8 16 25.1 17 25.4 18 25.9 19 27.4 20 29.4 4. Free Base Form B1 4.1 Characterization of Form B1 4.1.1 X-Ray Powder Diffractometry A Powder X-Ray Diffraction pattern of Form B1 was obtained by standard techniques at 301 K as described in the European Pharmacopeia 6 th Edition chapter 2.9.33, which is shown in FIG. 20 . A list of characteristic X-ray peaks derived from this pattern is provided in Table XV: No. °2θ (Cu-Kα 1 radiation) ± 0.2° 1 7.0 2 14.0 3 17.1 4 18.3 5 19.0 6 19.2 7 20.6 8 21.2 9 21.6 10 22.1 11 23.1 12 24.2 13 25.1 14 25.4 15 26.2 16 27.3 17 27.9 18 29.0 19 29.3 The most significant X-ray peaks from Table X are listed in Table XVI: No. °2θ (Cu-Kα 1 radiation) ± 0.2° 1 7.0 2 14.0 3 18.3 4 19.0 5 20.6 6 21.2 7 24.2 8 25.1 9 25.4 10 27.9 Therefore, in a preferred aspect the present invention relates to crystalline form B1 having characteristic peaks at the 2θ angles provided in Table XV. In a more preferred aspect the invention relates to form B1 having characteristic peaks at the 2θ angles provided in Table XVI. X-Ray Structural data were calculated from powder X-Ray data of Form B1 as shown in FIG. 21 . Form B1 crystallises in the chiral orthorhombic space group P2 1 2 1 2 1 with the lattice parameters a=20.8±0.1 Å, b=15.7±0.1 Å, c=5.0±0.1 Å α=β=γ=90°) at 301 K. From the crystal structure it is obvious that Form B1 represents an anhydrous form. In a specific aspect, the invention relates to a crystalline form of the free base of Compound C characterized by these crystallographic parameters. 4.1.2 Vibrational Spectroscopy Form B1 can be further characterized by infrared and Raman-spectroscopy. FT-Raman and FT-IR spectra have been obtained by standard techniques as described in the European Pharmacopeia 6 th Edition chapter 2.02.24 and 2.02.48. For measurement of the FT-IR and FT-Raman-spectra a Bruker Vector 22 and a Bruker RFS 100 spectrometer have been used. FT-IR spectra and FT-Raman spectra have been base-line corrected using Bruker OPUS software. An FT-IR spectrum has been obtained using a KBr pellet as sample preparation technique. The FT-IR spectrum is shown in FIG. 22 from which the following band positions were derived (±2 cm −1 , relative intensity*): 3329 cm −1 (s), 2935 cm −1 (w), 1638 cm −1 (s), 1604 cm −1 (s), 1585 cm −1 (s), 1555 cm −1 (s), 1516 cm −1 (s), 1422 cm −1 (s), 1398 cm −1 (m), 1337 cm −1 (s), 1228 cm −1 (m), 1098 cm −1 (m), 1071 cm −1 (m), 1028 cm −1 (s) *“s”=strong (transmittance≦50%), “m”=medium (50%<transmittance≦70%), “w”=weak (transmittance>70%) An FT-Raman spectrum is shown in FIG. 23 from which the following band positions were derived (±2 cm −1 , relative intensity*): 3081 cm −1 (w), 2918 cm −1 (w), 1604 cm −1 (s), 1553 cm −1 (m), 1323 cm −1 (m), 1253 cm −1 (m), 1228 cm −1 (m), 1134 cm −1 (w), 1077 cm −1 (m), 935 cm −1 (w), 785 cm −1 (w), 630 cm −1 (w), 529 cm −1 (w) *“s”=strong (relative Raman intensity≧0.1), “m”=medium (0.1>relative Raman intensity≧0.02), “w”=weak (relative Raman intensity<0.02) 4.1.3 Other Analytical Methods It could be shown that Form B1 is a crystalline anhydrous form, which is further characterised by the following physical properties: Thermal behaviour of Form B1 shows a melting peak at approx. 165° C., with very small weight loss up to this temperature only. DSC and TGA profiles are displayed in FIGS. 24 and 25 , respectively. DSC scan of Form B1 was acquired on a Mettler-Toledo DSC 821 with a heating rate of 5 K/min, using nitrogen purge gas at 50 mL/min. TGA scan of Form B1 was acquired on a Mettler-Toledo TGA 851 with a heating rate of 5 K/min, using nitrogen purge gas at 50 mL/min. Water Vapour Sorption behaviour shows small water uptake levels<1 wt % in the relative humidity (RH) range 0-80% RH, and slightly enhanced water uptake at elevated RH. Form A1 can be classified as slightly hygroscopic acc. to Ph. Eur. criteria. Water Vapor Sorption isotherm (25° C.) of Form B1 is displayed in FIG. 26 . Water Vapour Sorption isotherm was acquired on a DVS-1 System from SMS. From solvent-mediated competitive slurry conversion experiments with binary phase mixtures of forms B1 and B2 in different solvents at ambient and at 50° C., Form B1 is clearly shown to result as solid-state residue at the expense of Form B2, thus confirming Form B1 as thermodynamically more stable free base form (see Example 6). Solubility in USP phosphate buffer (pH 7.4) at 37° C. was determined to be approx. 50 μg/mL (see Example 7). Overall, Form B1 reveals very good solid-state properties (good crystallinity, slightly hygroscopic only, sufficient thermal stability), which are favourable properties for solid dosage formulations. Moreover, Form B1 can be considered as thermodynamically stable crystalline form of the free base. 4.2 Processes for the Preparation of B1 4.2.1 Method 1 Approx. 260 g of Compound C hydrochloride salt were dispersed in 6.5 L Water at RT, and stirred for 5 minutes. After addition of approx. 598 mL aqueous NaOH solution (1 N), a thick suspension is formed. The suspension is further agitated for approx. 10 minutes, before approx. 2.6 L Ethylacetate are added. The dispersion is further agitated for 20 minutes at RT, and is then filtrated and washed twice with approx. 260 mL water. The resulting filter residue is then dried under vacuum at 40° C. overnight. 4.2.2 Method 2 Approx. 20 mg of Compound C form B1 were dispersed in 1 mL 2-Propanol at RT. The dispersion was heated to 60° C., resulting in a clear solution, which was further filtrated over a 0.2 μm syringe filter. The clear warm solution was then cooled down to 4° C. at 0.1° C./min, resulting in a dispersion with crystals. Crystals were separated by filtration from the mother liquor, and left open at ambient conditions to evaporate residual solvents. 4.2.3 Method 3 Approx. 20 mg of Compound C form B1 were dispersed in 1 mL n-Butanol at RT. The dispersion was heated to 60° C., resulting in a clear solution, which was further filtrated over a 0.2 μm syringe filter. The clear warm solution was then cooled down to 4° C. at 0.1° C./min, resulting in a dispersion with crystals. Crystals were separated by filtration from the mother liquor, and left open at ambient conditions to evaporate residual solvents. 4.2.4 Method 4 Approx. 20 mg of Compound C form B1 were dispersed in 2 mL Methylethylketone at RT. The dispersion was heated to 60° C., resulting in a clear solution, which was further filtrated over a 0.2 μm syringe filter. The clear warm solution was then cooled down to 4° C. at 0.1° C./min, resulting in a dispersion with crystals. Crystals were separated by filtration from the mother liquor, and left open at ambient conditions to evaporate residual solvents. 5. Free Base Form B2 5.1 Characterization of Form 82 5.1.1 X-ray powder diffractometry A Powder X-Ray Diffraction pattern of Form B2 has been obtained by standard techniques at 301 K as described in the European Pharmacopeia 6 th Edition chapter 2.9.33, which is shown in FIG. 27 . A list of characteristic X-ray peaks derived from this pattern is provided in Table XVII: No. °2θ (Cu-Kα 1 radiation) ± 0.2° 1 5.8 2 8.7 3 10.9 4 11.6 5 15.6 6 15.9 7 17.4 8 18.2 9 18.8 10 19.2 11 19.8 12 20.2 13 20.7 14 21.3 15 22.3 16 22.9 17 23.3 18 23.6 19 24.6 20 25.0 21 26.0 22 30.0 The most significant X-ray peaks from Table XVII are listed in Table XVIII: No. °2θ (Cu-Kα 1 radiation) ± 0.2° 1 8.7 2 15.9 3 17.4 4 18.2 5 18.8 6 19.2 7 21.3 8 22.3 9 23.3 10 26.0 Therefore, in a preferred aspect the present invention relates to crystalline form B2 having characteristic peaks at the 2θ angles provided in Table XVII. In a more preferred aspect the invention relates to form B2 having characteristic peaks at the 2θ angles provided in Table XVIII. X-Ray Structural data were calculated from powder X-Ray data of Form B2 as shown in FIG. 28 . Form B2 crystallises in the chiral triclinic space group P1 with the lattice parameters a=11.7±0.1 Å, b=15.7±0.1 Å, c=4.8±0.1 Å, α=92.2±0.5°, β=101.3±0.5°, γ=102.9±0.5° at 301 K. From the crystal structure it is obvious that Form B2 represents an anhydrous form. In a specific aspect, the invention relates to a crystalline form of the free base of Compound C characterized by these crystallographic parameters. 5.1.2 Vibrational Spectroscopy Form B2 can be further characterized by infrared and Raman-spectroscopy. FT-Raman and FT-IR spectra have been obtained by standard techniques as described in the European Pharmacopeia 6 th Edition chapter 2.02.24 and 2.02.48. For measurement of the FT-IR and FT-Raman-spectra a Bruker Vector 22 and a Bruker RFS 100 spectrometer have been used. FT-IR spectra have been base-line corrected using Bruker OPUS software. FT-Raman spectra have been vector normalized using the same software. An FT-IR spectrum has been obtained using a KBr pellet as sample preparation technique. The FT-IR spectrum is shown in FIG. 29 from which band positions are given below. Form B2 IR band positions (±2 cm −1 , relative intensity*) 3287 cm −1 (m), 2893 cm −1 (w), 1646 cm −1 (m), 1603 cm −1 (s), 1586 cm −1 (s), 1554 cm −1 (s), 1518 cm −1 (s), 1422 cm −1 (m), 1401 cm −1 (m), 1333 cm −1 (s), 1227 cm −1 (m), 1106 cm −1 (m), 1062 cm −1 (m), 1023 cm −1 (m) *“s”=strong (transmittance<50%), “m”=medium (50%<transmittance≦70%), “w”=weak (transmittance>70%) An FT-Raman spectrum is shown in FIG. 30 from which band positions were derived as given below. Form B2 Raman band positions (±2 cm −1 , relative intensity*): 3074 cm −1 (w), 2915 cm −1 (w), 1607 cm −1 (s), 1555 cm −1 (m), 1322 cm −1 (m), 1255 cm −1 (m), 1228 cm −1 (m), 1137 cm −1 (m), 1079 cm −1 (m), 941 cm −1 (w), 787 cm −1 (w), 630 cm −1 (w), 527 cm −1 (w) *“s”=strong (relative Raman intensity≧0.1), “m”=medium (0.1>relative Raman intensity≧0.02), “w”=weak (relative Raman intensity<0.02) 5.1.3 Other Analytical Methods It could be shown that Form B2 is a crystalline anhydrous form, which is further characterised by the following physical properties: Thermal behaviour of Form B2 can be differentiated in two different morphological types, i.e. depending on particle properties of respective form B2 samples: a) Morphological Type 1 shows a melting peak at approximately 145° C., overlapped by immediate re-crystallisation at approx. 155° C., and subsequent melting of the recrystallised phase B1 at approx. 165° C. Only small weight loss is observed up to the melting temperature of the original phase. b) Morphological Type 2 shows an exothermic phase transition to form B1 at approx. 137° C., and subsequent melting of the formed phase at approx. 166° C. Only small weight loss is observed up to the phase transition temperature. DSC scans of Form B2 Type 1, as shown in FIGS. 31 and 33 , were acquired on a Mettler-Toledo DSC 821 with a heating rate of 5 K/min, using nitrogen purge gas at 50 mL/min. TGA scans of Form B2 Type 2, as shown in FIGS. 32 and 34 , were acquired on a Mettler-Toledo TGA 851 with a heating rate of 5 K/min, using nitrogen purge gas at 50 mL/min. Water Vapour Sorption behaviour shows small water uptake levels ˜1 wt % in the relative humidity (RH) range 0-80% RH, and slightly enhanced water uptake at elevated RH ( FIG. 35 ). Form B2 can be classified as slightly hygroscopic acc. to Ph. Eur. criteria. Water Vapor Sorption isotherm (25° C.) of Form B2 is displayed below. Water Vapour Sorption isotherm was acquired on a DVS-1 System from SMS. Solubility in USP phosphate buffer (pH 7.4) at 37° C. was determined to be approx. 70 μg/mL (see Example 7). Overall, Form B2 reveals good solid-state properties (crystallinity, slightly hygroscopic, sufficient thermal stability), which are favourable properties for solid dosage formulations. 5.2 Processes for the Preparation of 82 5.2.1 Method 1 Approximately 10 mg of Compound C (free base) crystalline form B1 were dissolved in approx. 1 mL of a binary mixture of Toluene:Methanol (1:1, v:v) at 50° C. Solutions were filtered through 0.2 μm syringe filters into 4 mL glass vials, and left open at 50° C. until full evaporation of the solvent mixture was completed. The resulting crystals were gently dispersed into a powder using a spatula. 5.2.2 Method 2 Approximately 10 mg of Compound C (free base) crystalline form B1 were dissolved in approx. 1 mL of a binary mixture of Toluene:Ethanol (1:1, v:v) at 50° C. Solutions were filtered through 0.2 μm syringe filters into 4 mL glass vials, and left open at 50° C. until full evaporation of the solvent mixture was completed. The resulting crystals were gently dispersed into a powder using a spatula. 5.2.3 Method 3 Approximately 10 mg of Compound C (free base) crystalline form B1 were dissolved in approx. 2.5 mL of a binary mixture of Toluene:Acetone (1:1, v:v) at 50° C. Solutions were filtered through 0.2 μm syringe filters into 4 mL glass vials, and left open at 50° C. until full evaporation of the solvent mixture was completed. The resulting crystals were gently dispersed into a powder using a spatula. 5.2.4 Method 4 Approximately 10 mg of Compound C (free base) crystalline form B1 were dissolved in approx. 4 mL of a binary mixture of Toluene:Methylethylketone (1:1, v:v) at 50° C. Solutions were filtered through 0.2 μm syringe filters into 4 mL glass vials, and left open at 50° C. until full evaporation of the solvent mixture was completed. The resulting crystals were gently dispersed into a powder using a spatula. 5.2.5 Method 5 Approximately 10 mg of Compound C (free base) crystalline form B1 were dissolved in approx. 8.5 mL of a binary mixture of Toluene:Ethylacetate (1:1, v:v) at 50° C. Solutions were filtered through 0.2 μm syringe filters into 4 mL glass vials, and left open at 50° C. until full evaporation of the solvent mixture was completed. The resulting crystals were gently dispersed into a powder using a spatula. 5.2.6 Method 6 Approximately 10 mg of Compound C (free base) crystalline form B1 were dissolved in approx. 10.5 mL of a binary mixture of Toluene:Chloroforme (1:1, v:v) at 50° C. Solutions were filtered through 0.2 μm syringe filters into 4 mL glass vials, and left open at 50° C. until full evaporation of the solvent mixture was completed. The resulting crystals were gently dispersed into a powder using a spatula. 5.2.7 Method 7 Approximately 10 mg of Compound C (free base) crystalline form B1 were dissolved in approx. 2.5 mL of a binary mixture of Toluene:Dioxane (1:1, v:v) at 50° C. Solutions were filtered through 0.2 μm syringe filters into 4 mL glass vials, and left open at 50° C. until full evaporation of the solvent mixture was completed. The resulting crystals were gently dispersed into a powder using a spatula. 5.2.8 Method 8 Approximately 10 mg of Compound C (free base) crystalline form B1 were dissolved in approx. 4 mL of Toluene at ambient conditions (approx. 23° C.). Solutions were filtered through 0.2 μm syringe filters into 4 mL glass vials, and left open at ambient conditions until full evaporation of the solvent was completed. The resulting crystals were gently dispersed into a powder using a spatula. 6. Solvent-Mediated Competitive Slurry Conversion Experiments with Binary Phase Mixtures of Forms B1+B2 Approximately 10 mg of Compound C (free base) crystalline form B1 and approx. 5 mg of Compound C (free base) crystalline form B2 were dispersed in 200-1000 μL solvent in 4-mL glass vials. A PTFE-coated magnetic stirring bar was inserted into the dispersions, and the vials were tightly closed with a screw cap containing a septum. Dispersions were agitated for 5 days on a magnetic stirrer at ambient conditions (˜23° C.) and 50° C., respectively. Dispersions were then vacuum-filtrated over a Whatman paper filter, and collected filter residues were analysed by X-Ray-Diffraction for identity with the initially used materials. Results from competitive slurry conversion experiments are summarised below. Binary mixture B1:B2 (approx. 2:1, wt/wt) slurried 5 days in RT 50° C. Water B1 B1 2-Propanol B1 B1 Ethanol B1 B1 THF B1 B1 Acetone B1 B1 Acetonitrile B1 B1 Ethlyacetate B1 B1 MTBE B1 B1 Chloroforme B1 B1 n-Hexane B1 B1 It can clearly be seen that form B1 results as solid-state residue from all competitive slurry conversion experiments starting from mixtures with B2, clearly revealing form B1 as more stable form between RT and 50° C. 7. Determination of Thermodynamic Solubility of Forms B1 and B2 in Water Approximately 17 mg of Compound C (free base) crystalline form B1 were dispersed in 2 mL USP Phosphate Buffer (pH 7.4) in Whatman Uniprep Syringless Filter vials in duplicate preparations. Approximately 17 mg of Compound C (free base) crystalline form B2 were dispersed in 2 mL USP Phosphate Buffer (pH 7.4) in Whatman Uniprep Syringless Filter vials in duplicate preparations. All dispersions were agitated at 37° C. for 24 hours. Dispersions were then filtered via the internal filter of the Uniprep vials, and clear filtrates were analysed by HPLC for dissolved quantities of Compound C. Solid state residues were analysed by X-Ray-Diffraction for identity with the initially used materials. Results from solubility determinations are summarised below. Investigated Form Solubility (μg/mL) Solid-state residue Free Base Form B1 #1: 49 #1 + #2: #2: 56 Free Base Form B1 Free Base Form B2 #1: 71 #1 + #2: #2: 67 Free Base Form B1 Although both preparations of form B2 undergo phase conversion to form B1 upon longterm slurrying in PBS buffer, it can clearly be seen that form B2 exhibits an increased supersaturated solubility level compared to form B1. 8. Solvates of the Free Base of Compound C In addition to Forms B1 and B2 described above a series of solvate forms of the free base of C were also identified, which were not further characterised in terms of physical properties. 8.1 Acetic Acid Solvate Form B-S1 From the powder X-ray diffractogram of Form B-S1 shown in FIG. 36 the following peaks were derived—Table XIX: No. °2θ (Cu-Kα 1 radiation) ± 0.2° 1 8.0 2 18.9 3 20.2 4 20.9 5 21.4 6 21.6 7 22.2 8 23.2 9 23.3 10 23.7 11 24.1 12 24.4 13 24.6 14 24.8 15 25.4 16 26.5 17 26.6 8.2 Dioxane Solvate Form B-S2 From the powder X-ray diffractogram of Form B-S2 shown in FIG. 37 the following peaks were derived—Table XX: No. °2θ (Cu-Kα 1 radiation) ± 0.2° 1 4.0 2 5.8 3 8.7 4 15.4 5 15.7 6 17.4 7 17.9 8 18.8 9 19.0 10 19.6 11 20.8 12 21.2 13 21.7 14 21.9 15 22.4 16 23.0 17 23.7 18 24.2 19 25.4 20 27.1 21 27.3 9. Solubility Determinations of HCl Salt Forms Vs. Free Base Approximately 10 mg of Compound C hydrochloride salt form A1 were dispersed in 2 mL DI water in Whatman Uniprep Syringless Filter vials. Approximately 10 mg of Compound C hydrochloride salt form A2 were dispersed in 2 mL DI water in Whatman Uniprep Syringless Filter vials. Approximately 10 mg of Compound C free base form were dispersed in 2 mL DI water in Whatman Uniprep Syringless Filter vials. All dispersions were agitated at 37° C. for 24 hours. Dispersions were then filtered via the internal filter of the Uniprep vials, and clear filtrates were analysed by HPLC for dissolved quantities of Compound C. Solid state residues were analysed by X-Ray-Diffraction for identity with the initially used materials. Results from solubility determinations are summarized below. Compound Solubility (mg/mL) Solid-state Residue HCl salt Form A1 2.8 (Water) Free base Form B1 43.6 (0.1N HCl) HCl salt Form A1 HCl salt Form A2 2.5 (Water) Free base Form B1 >20 (0.1N HCl) No residue obtained Free Base Form B1 <0.1 (Water) Free base Form B1 17.5 (0.1N HCl) HCI salt Form A1 Both hydrochloride salt forms exhibit significantly higher solubility levels in 0.1. N HCl and DI Water compared to free base. 10. Dissolution Studies of HCl Salt Forms Vs. Free Base Approximately 10 mg of Forms A1, A2 or B1, respectively, were accurately weighed and blended with 2 g glass beads in a Vortex mixer. The blends were then placed into a powder cell of a Flow-Through-Cell system. Dissolution studies were performed at 37° C. over 30-60 minutes at a constant flow rate of 16 mL/min. Fractions of dissolution medium after passing the Flow-Through-Cell were collected in 1 minute intervals in the first 10 minutes, in 5 minute intervals from 10-30 minutes, and in 15 minute intervals from 30-60 minutes. Dissolved levels of API in each fraction were analysed by HPLC. In dissolution experiments with HCl salt forms at pH 5.0 and pH 6.8, free base fractions which precipitated over time from the initially clear solutions in the collected dissolution fractions were re-dissolved by addition of sulphuric acid prior to HPLC analysis. All experiments were performed as triplicate preparations, with results reported as mean values from triplicates, and error bars as single standard deviations from the triplicates. Results from API Dissolution studies are displayed in FIGS. 38 , 39 , 40 and 41 . pH 1.2: The following % dissolved levels are obtained after 30 minutes: HCl Salt Form A1: 100% HCl Salt Form A2: 99% Free base Form B1: 100% pH 3.0: The following % dissolved levels are obtained after 30 minutes: HCl Salt Form A1: 100% HCl Salt Form A2: 100% Free base Form B1: 83% pH 5.0: The following % dissolved levels are obtained after 30 minutes: HCl Salt Form A1: 97% HCl Salt Form A2: 98% Free base Form B1: 57% pH 6.8: The following % dissolved levels are obtained after 30 minutes: HCl Salt Form A1: 96% HCl Salt Form A2: 96% Free base Form B1: 52% All solid state forms of Compound C, including any salts and solvates, and all manufacturing methods described herein are also comprised by, and object of, the present invention.

The invention relates to solid state forms of N—((S)-2,3-Dihydroxy-propyl)-3-(2-fluoro-4-iodo-phenylamino)-isonicotinamide, processes for their preparation, and medical uses thereof.

This application is a division of application Ser. No. 06/322,109, filed Nov. 16, 1981 now U.S. Pat. No. 4,356,059. BACKGROUND OF INVENTION 1. Field of Invention This invention relates to a method and apparatus for manufacturing a bulky, soft and absorbent paper web. 2. Description of the Prior Art U.S. patent application Ser. No. 933,203 Hulit, et al., filed Aug. 14, 1978, relates to a system for producing a bulky, soft and absorbent paper web using mechanical means to predry the web. The structure for predrying the web includes a papermaker's felt and imprinting fabric of a specific character and a pair of opposed rolls creating a compression nip defined by the fabric and felt through which the web is passed and partially dewatered. According to the aforesaid application, the web prior to entering the fabric-felt compression nip is essentially uncompacted and the fabric-felt arrangement comprises the initial predrying stage in the system. Since the imprinting fabric then carries the predried web in undisturbed condition to a Yankee dryer or other component defining a heated drying surface, the only significant compacting of the web that occurs in the system of the aforesaid application is at the location of the compaction elements or knuckles of the imprinting fabric. As a consequence, a soft, bulky and absorbent sheet is produced through use of the system covered thereby. U.S. patent application Ser. No. 280,752, R. E. Hostetler, filed July 6, 1981, also relates to a system for producing a bulky, soft and absorbent paper web. In accordance with the teachings of this latter application a wet web of principally lignocellulosic fibers is positioned on a first dewatering felt and then conveyed by the felt through a first nip formed by it and a second dewatering felt to remove water from the web. The partially dewatered web is then conveyed to a second nip formed between a dewatering felt and an open mesh imprinting fabric formed of woven filaments, the fabric having spaced compaction elements and defining voids between the filaments. While the partially dewatered web is in the second nip, it is impressed against the fabric by the felt to force a predetermined portion of the web into the voids and provide bulk thereto. The web is then retained on the imprinting fabric after the web passes through the second nip and removed therefrom before final drying by applying the web to a creping surface at a third nip location, the third nip being formed between the creping surface and the imprinting fabric. The web is retained on the imprinting fabric in an essentially undisturbed condition during retention and transport thereof on the imprinting fabric between the second and third nips. BRIEF SUMMARY OF THE INVENTION The present invention also relates to a system for manufacturing a bulky, soft and absorbent paper web, and in common with the inventions covered by the two aforesaid applications, the present system utilizes an imprinting fabric to felt press in a stage of its operation. As compared to such prior art arrangements, however, the current system also incorporates two rotatable dryer means having smooth heated surfaces to which the web is applied and is removed therefrom in serial fashion after passing through the imprinting fabric-felt press. Specifically, the wet paper web is applied to the surface of the first rotatable dryer means, compacted substantially overall while on the surface, and removed therefrom. The partially dewatered web is then introduced into a wet embossing nip formed between a felt and an open mesh imprinting fabric formed of woven filaments having spaced compaction elements and defining voids between the filaments. While the web is in the wet embossing nip it is impressed against the fabric whereby from about 5% to about 50% of the web will be compacted by the compaction elements and from about 50% to 95% of the web will be impressed into the voids. The web is retained on the imprinting fabric after passing through the wet embossing nip and is transported by the fabric into contact with a heated surface of a second rotatable dryer means. The web is then dry creped from the second heated surface. Through utilization of this system, a high bulk, low density dry creped tissue is produced and drying costs minimized. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic side view of a preferred form of apparatus constructed in accordance with the teachings of the present invention and for carrying out the method thereof; and FIG. 2 is a view similar to that of FIG. 1 but illustrating an alternative form of apparatus. DETAILED DESCRIPTION Referring now to FIG. 1, a papermaking machine constructed in accordance with the teachings of the present invention is illustrated. The machine includes a paper web-forming device of any suitable type such as a Fourdrinier machine, the Fourdrinier wire 11 of which is illustrated. The Fourdrinier wire delivers the wet web W (normally in the order of from about 7% to about 23% solids) to a pick-up felt 14 forming an endless loop about a plurality of rollers including a suction pressure roll 16 and a blinded drilled pressure roll 18. Web pick-up by the felt may be facilitated through use of a steam box arrangement under the wire at the vacuum slot pick-up 20. Preferably a water shower 22 and uhle box combination are provided to clean and condition the felt prior to web pick-up. Felt 14 forms a nip with a rotatable dryer can 26 which is heated by steam or other means and has a smooth solid outer surface. Transfer of the web W takes place at the location of suction pressure roll 16 so that roll 16 and the dryer can compact the web overall. While on the dryer can the web also passes through a nip defined by the pick-up felt and the dryer can in the vicinity of pressure roll 18. From that second nip continued rotation of the dryer can brings the web into contact with an imprinting fabric 30 looped about a roll 32 which may be plain or suction. Closely adjacent to roll 32 the web W is removed from dryer can 26 by a skinning doctor 34 and the web is applied to the imprinting fabric 30. U.S. patent application Ser. No. 933,203 Hulit et al., filed Aug. 14, 1978, may be referred to for details of an imprinting fabric preferred for use in connection with the present invention. Specifically the imprinting fabric disclosed therein is an open mesh fabric formed of woven filaments. The fabric has compaction elements defined by the knuckles formed at the warp and weft crossover points of the fabric filaments and defines voids between the filaments. The imprinting fabric has a surface void volume of from about 15 cc/m 2 to about 250 cc/m 2 and preferably from about 40 cc/m 2 to about 150 cc/m 2 . The compaction element area of the imprinting fabric constitutes between about 5% and about 50%, and preferably from about 20% to about 35%, of the total web supporting surface area of the fabric. Imprinting fabric 30 is in the form of a continuous loop rotating in a clockwise manner as viewed in FIG. 1. At the time the partially dewatered web is applied to the imprinting fabric 30 it has an overall fiber consistency of from about 40% to about 50%. The partially dewatered web then passes through a nip formed between the imprinting fabric and a papermaker's dewatering felt 36 also in the form of a continuous loop and moving in a counterclockwise manner as viewed in FIG. 1. A pressure roll 38 is in opposition to roll 32 to provide the desired nip pressure between the felt 36 and fabric 30. The imprinting fabric-felt press just described serves to increase the apparent bulk of web W by impressing from about 50% to 95% of the web into the voids of the imprinting fabric with the only significant compaction of the web taking place in the vicinity of the compaction elements. As noted in the aforesaid Hulit et al. application, an imprinting fabric of the type just described will retain the wet paper web impressed therein by the papermakers' dewatering felt after passing through the nip formed by these two elements. The web W is now transferred to a through dryer 42 comprising a rotatable perforated dryer drum 44 and an outer hood 46 which receives the pressurized hot air or other heated fluid from the rotatable perforated drum in the conventional manner. The imprinting fabric 30 is looped about the perforated dryer drum 44 so that the web W passes about almost the entire circumference of the dryer drum sandwiched between the drum outer surface the imprinting fabric. After the web has passed through the through dryer it has an overall fiber consistency generally equal to or greater than 80% solids. The web is then transported by imprinting fabric 30 to a Yankee dryer 50 and applied to the smooth heated outer creping surface thereof. Transfer to the Yankee takes place at the location of a solid Yankee pressure roll 52 with transfer to the creping surface preferably being facilitated by the application of a suitable adhesive, such as animal glue, to the Yankee surface or web by any suitable adhesive applicator 54 just prior to engagement of the web W with the Yankee creping surface. After being rotated about the Yankee drum the web is creped therefrom by a creping blade 56 and transferred to a suitable winding mechanism. As the imprinting fabric continues its travel from the Yankee back to the dryer can, it is cleaned as by means of a vacuum box 60 and air jet 62. The air jet may also be utilized to apply a spray of release agent such as emulsified mineral oil in water to the imprinting fabric. FIG. 2 illustrates in schematic fashion an alternative form of papermaking machine layout incorporating the teachings of the present invention. The arrangement is in most respects identical to the arrangement of FIG. 1 and for this reason like components have been designated by the same reference numerals employed with respect to the FIG. 1 embodiment. The principal difference of this configuration as compared to that of FIG. 1 resides in the elimination of a through air dryer in the arrangement. Rather than proceed through a through dryer the imprinting fabric 30 transfers the web directly to the creping surface of the Yankee 50. It is obvious that the web W will be much wetter (in the order of 40-50% solids) when applied to the Yankee surface in FIG. 2 than is the case in the FIG. 1 embodiment. For this reason, the drying capacity of the Yankee 50 in FIG. 2 must be much greater, requiring either a larger Yankee or a reduction in web speed. Another difference resides in the fact there is an open draw between roll 32 and dryer can 26. This open draw arrangement could also be utilized in connection with the system of FIG. 1.

A system for producing a bulky, soft and absorbent paper web wherein the web is creped from a first creping surface, passes through a nip formed between a dewatering felt and imprinting fabric of a specified character and is applied to and creped from a second creping surface.

RELATED APPLICATIONS [0001] This application claims the benefit of the filing date of U.S. Provisional Application No. 61/071,036 filed Apr. 9, 2008, and U.S. Provisional Application No. 61/136,727 filed Sep. 29, 2008, incorporated in their entirety by reference. FIELD OF THE INVENTION [0002] The present invention relates generally to an enterprise application. More particularly, the present invention relates to supplier and customer collaboration services in an alert distribution and management system. BACKGROUND OF THE INVENTION [0003] When a product supplier, such as a manufacturer, a distributor, or a reseller, determines that a product is defective or requires a customer intervention, the product supplier may issue an alert (e.g., a recall notice, field correction, repair instructions, etc.) to notify customer organizations and users to stop using the product, return the product, etc. Issuing an alert is costly to a product supplier because an alerted product may need to be replaced or fully refunded, but it often limits liability for a product supplier, protects public safety, and prevents further damage to the product supplier's corporate or trade image. To maximize these efforts, the product supplier should inform the affected parties as quickly as possible to limit potential safety implications. [0004] A product alert may not be easy to learn about because, for example, a product supplier may not always widely publicize an alert. A product supplier may merely notify a government agency and/or only a few affected customer organizations. These types of alerts may not be publicized beyond the small subset of the customer communities. Further, a customer organization may have hundreds or thousands of products to search for alerts on and only limited resources for handling alerts. SUMMARY OF THE INVENTION [0005] An alert distribution and management system with supplier and customer collaboration services using information technology may alleviate the supplier and customer collaboration problems in alert and returns management. One example of such a system may be the collaborative Risk and Safety Management Alert System (RASMAS) from Noblis. The alert distribution and management system with supplier and customer collaboration services provides new capabilities for product suppliers to collaborate with users and customer organizations related to remediation of alerted products and for the users and customer organizations to collaborate with one another in handling alerts. [0006] In an alert distribution and management system consistent with embodiments of the present invention, alert-related remediation data may be analyzed and provided to product suppliers. Access to remediation data may enable product suppliers to evaluate alert and remediation processes, tailor future alerts, and monitor remediation efforts. Product suppliers may also manage reimbursement and repair of alerted products based on the remediation data. Using collaborative technologies and content management solutions provided by the system, product suppliers may manage remediation data, and distribute alert handling information, including multimedia, to specific users and customer organizations. [0007] In addition, in an alert distribution and management system consistent with embodiments of the present invention, a user or customer organization may collaborate with other users or customer organizations in a community setting. In the community, a community member may be associated with a specific alert, and community members may be able to seek assistance or information from other community members who may be experts in handling a specific alert or in an alerted product. Community members having expertise may have a rating, ranking, or other indicator of the level of expertise. A member may be able to search and/or identify an expert based on different search criteria. The system may also promote collaboration among community members by forming an association to connect community members that perform similar roles in their respective customer organizations. [0008] Consistent with embodiments of the invention, a method for managing remediation of alerted products implemented using a computer having a processor and a display device is provided. The method comprises identifying an alert related to a product. The method also comprises facilitating handling of the alert by a user of the product. The method further comprises receiving data related to alert handling from the product user. The method further comprises analyzing the data related to alert handling with other data related to the alert. The method further comprises displaying the analyzed data on the display device. The method further comprises, based on the analyzed data, monitoring remediation efforts related to the alert. [0009] In another embodiment, a method for facilitating collaboration in alert handling among a plurality of users of a product using a computer having a processor is provided. The method comprises, for each of the plurality of product users, creating a profile specifying the user's role in handling alerts related to the product and a ranking of the user's expertise in alert handling. The method also comprises associating one product user with another product user based on the user profiles. The method further comprises providing a forum for the associated product users to share information related to alert handling. [0010] In yet another embodiment, a system for managing remediation of alerted products is provided. The system comprises software components embodied on a computer-readable medium. The software components comprise an alert distribution and management component configured to identify an alert related to a product, facilitate handling of the alert by a user of the product, and receive data related to alert handling from the product user. The software components also comprise a collaboration component configured to analyze data related to alert handling with other data relating to the alert, and monitor remediation efforts related to the alert based on the analyzed data. The system also comprises a display device for displaying the analyzed data. [0011] It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only, and should not be considered restrictive of the scope of the invention, as claimed. Further features and/or variations may be provided in addition to those set forth herein. For example, embodiments consistent with the present invention may be directed to various combinations and subcombinations of the features described in the following detailed description. BRIEF DESCRIPTION OF THE DRAWINGS [0012] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate various embodiments and aspects of the present invention. In the drawings: [0013] FIG. 1 is a block diagram illustrating an exemplary alert distribution and management system with supplier and customer collaboration services consistent with embodiments of the present invention; [0014] FIG. 2 is a flow diagram illustrating an exemplary alert collection and distribution process consistent with embodiments of the present invention; [0015] FIG. 3 is a flow diagram illustrating an exemplary alert management and coordination assignment process consistent with embodiments of the present invention; [0016] FIG. 4 is a block diagram illustrating an exemplary alert escalation process consistent with embodiments of the present invention. [0017] FIGS. 5A-5D are screen displays of web pages generated and presented by an exemplary web application of an alert distribution and management system consistent with embodiments of the present invention; [0018] FIGS. 6A-6G are screen displays of web pages generated and presented by an exemplary web application of supplier and customer collaboration services consistent with embodiments of the present invention; [0019] FIG. 7 is a context diagram illustrating exemplary interactions between components in an exemplary alert distribution and management system with supplier and customer collaboration services consistent with embodiments of the present invention; [0020] FIG. 8 is a screen display of an exemplary communication tool for customers in an alert distribution and management system with supplier and customer collaboration services consistent with embodiments of the present invention; [0021] FIG. 9 is a screen display of an exemplary report of remediation data consistent with embodiments of the present invention; [0022] FIGS. 10A-10C are screen displays of sample reports of remediation data consistent with embodiments of the present invention; and [0023] FIG. 11 is a context diagram illustrating exemplary interactions among members of collaboration communities in an exemplary alert distribution and management system with supplier and customer collaboration services consistent with embodiments of the present invention. DESCRIPTION [0024] Reference will now be made in detail to embodiments of the invention, examples of which are illustrated in the accompanying drawings. Implementations set forth in the following description do not represent all implementations consistent with the claimed invention. Instead, they are merely some examples consistent with certain aspects related to the invention. Wherever possible, the same reference numbers will be used throughout the drawings to refer to the same or like parts. [0025] Once a user is notified of an alert, it can be difficult to learn about how to handle the alert. For example, an alert may be handled by removing, repairing, returning a defective product, changing a defective procedure, etc. Once a customer organization, such as a healthcare provider, has developed a response procedure or expertise in handling a particular alert, other customer organizations may benefit from sharing the expertise. However, the customers in need of assistance in handling alerts may not even know where to seek help resolving alerts. Even when information on handling alerts is available, it may be difficult to assess whether the information is reliable or from a trustworthy source. There may also be a type of alert that requires collaboration among many entities, for example, when a recall must involve removing all or a majority of recalled products from the market. Bringing affected customer organizations, especially healthcare providers, together to collectively handle alerts can be difficult. [0026] In some instances, product suppliers may be the best source of expertise in handling alerts; however, product suppliers may often lack infrastructure to send the information to the affected customer organizations without alarming their unaffected customer base. Products are normally distributed to multiple users, directly or indirectly, and product suppliers, particularly manufacturers, often lack infrastructure or process to precisely learn the final destinations of their products. Product suppliers may benefit from learning how their products are remediated at various customer and/or user locations after recall notices have been sent out. The information collected from different users may help product suppliers to assess the damages resulting from alerts, and may be used to better manage the alerts and their businesses. The information may also be distributed to the customer organizations that are in need of help in handling the alerts. However, product suppliers also often lack mechanisms to collaborate with their customer organizations related to remediation of their alerted products, and to distribute information related to their products and remediation to specific customer organizations or users. [0027] FIG. 1 illustrates an exemplary alert distribution and management system with supplier and customer collaboration services 110 . As shown in FIG. 1 , system 110 may include alert processor 112 , services component 113 , database 114 , web application 116 , and interface component 118 . Alert processor 112 , services component 113 , database 114 , web application 116 , and interface component 118 may include any number of computers, devices, hardware, and/or mainframe located anywhere and distributed among multiple locations. Alert processor 112 , services component 113 , database 114 , web application 116 , and interface component 118 may also include operating systems, such as Microsoft Windows™, or any UNIX derived operating system, such as Linux™, Solaris™, and FreeBSD. [0028] Alert processor 112 may perform alert distribution and management functionality, such as alert collection, distribution, management, and coordination assignment. For example, alert processor 112 may enable establishing accounts for new alert subscribing customer organizations and enable obtaining, enhancing, and distributing alerts to the customer organizations. To this end, alert processor 112 may perform alert collection and distribution process 200 and alert management and coordination assignment process 300 , as described in more detail with respect to FIGS. 2 and 3 , respectively. [0029] Services component 113 may provide supplier and customer collaboration services, such as enabling collaboration among product supplier 120 and/or customer organizations 130 , 140 , and 150 . For example, services component 113 may enable product supplier 120 to identify affected customer organizations and communicate information with the affected customer organizations. Services component 113 may also process remediation data collected from customer organizations 130 , 140 , and/or 150 for product supplier 120 to help product supplier 120 to evaluate its alert and remediation processes and efforts, plan its reimbursement and repair of alerted products, etc. For customer organizations 130 , 140 , and 150 , for example, services component 113 may enable user 132 of customer organization 130 to identify an expert in handling an alert or a product. The expert may be, for example, related to customer organization 140 or 150 , product supplier 120 or even within customer organization 130 . Once an expert is identified, services component 113 may enable user 132 to communicate with the identified expert via various communication channels. [0030] Database 114 may include a database management system (DBMS). The DBMS may store and retrieve data from, and manage database 114 . To this end, the DBMS may provide services such as transactions and concurrency, indexing, security, and backup and replication. The DBMS may be based on, for example, a relational model, object database model, post-relational database model, hierarchical model, or flat model. In certain embodiments, a DBMS may be implemented as Oracle™ DBMS, IBM's DB2™, Microsoft SQL Server™, PostgresSQL, or MySQL®. [0031] Database 114 may include a collection of data related to alert collection, distribution, management, and coordination assignment. For example, database 114 may store any data necessary for alert processor 112 to operate and provide its functionality. To this end, database 114 may include any data involved in alert collection and distribution process 200 and alert management and coordination assignment process 300 , as described in more detail with respect to FIGS. 2 and 3 , respectively. Database 114 may further include a collection of data related to management of returns, reimbursements, and replacements processes of alerted products. [0032] Database 114 may also include a collection of data related to supplier and customer collaboration services. For example, database 114 may store collaborating member profiles. Member profiles may be collected from users 132 , 134 , 136 , 142 , 144 , 152 , and/or 154 , and may include the name and address of the customer organizations that the users are associated with, the users' role in handling alerts within their customer organizations, etc. Member profiles may also include the users' contact information in case other users or product suppliers may desire to contact the users, data about specific products or alerts the users handle, etc. Database 114 may store product supplier profiles for one or more product suppliers 120 . Product supplier profile data may include product supplier's contact information, product supplier's preference information, etc. By providing product supplier's preference information, product supplier 120 may specify, for example, what and how data is collected from customer organizations and presented to the product supplier, channels of communication with customer organizations, etc. In addition, database 114 may store comments and ratings for the comments, supplied by participating members, relating to specific alerts and alert handling. [0033] Through member profiles, the users may indicate whether they would be willing to be contacted and/or the users' contact information may be made available to other members and product suppliers. To this end, the users may indicate their desired level of participation as members of collaboration communities, such as the community connection, described further in detail with respect to FIGS. 5 D and 6 A- 6 F. The users may also opt out of supplier and/or customer collaboration services if they desire. In certain embodiments, the users may use a registration process to join a collaboration community. During the registration process, the users may be provided with terms and conditions, and asked to accept them before joining a collaboration community. The member profile data may be used to search for experts and determine an expert's level of expertise. In certain embodiments, a comments and ratings section including comments from members may be used in determining the members' level of expertise, reliability, etc. In other embodiments, experts' level of expertise may be determined using an algorithm based on various factors to ensure that the level of expertise may be fairly and objectively represented to the members of collaboration communities. [0034] Web application 116 may include a web server. The web server may accept hypertext transfer protocol (HTTP/HTTPS) requests from users, such as product supplier 120 and users 132 , 134 , 136 , 142 , 144 , 152 , and 154 through network 172 , and send HTTP/HTTPS responses back to the users with web pages, which may comprise hypertext markup language (HTML) or extensible markup language (XML) documents and any linked or embedded objects, such as images, videos, and other multimedia. For example, the web server may exchange XML-based messages with the users using Simple Object Access Protocol (SOAP) on top of HTTP/HTTPS. In certain embodiments, web application 116 may enable the members of collaboration communities, such as product suppliers 120 and users 132 , 134 , 136 , 142 , 144 , 152 , and 154 , to communicate via chat rooms, live meetings, wiki collaboration, video training, etc. In other embodiments, web application 116 may rely on tools provided by a third party to enable the members of collaboration communities to communicate via chat rooms, live meetings, wiki collaboration, or video training. The web server may be implemented as Apache HTTP Server™, Internet Information Service (IIS)™, Sun Java System Web Server™, or IBM HTTP Server™ although any web server technologies may be used to provide the web server functionalities. [0035] Web application 116 may include an application server that enables dynamic generation of web pages. For example, web application 116 may be based on Java Enterprise Edition (JEE) technologies, such as Java Server Page™ (JSP) and Java Servlet™, to enable dynamic generation of web pages, and a JEE application server, such as IBM's WebSphere™, BEA's WebLogic™, JBOSS™, and JRun™, may be employed as an application server to support the technologies. Web application 116 may alternatively employ Microsoft .NET Framework™, such as ASP.NET™ to enable dynamic generation of web pages. [0036] Web application 116 may function as a user interface to system 110 , and expose the functionalities of alert processor 112 and services component 113 to product supplier 120 and users 132 , 134 , 136 , 142 , 144 , 152 , and/or 154 . To this end, web application 116 may present web pages to the users, receive requests originated from users, and repackage and/or relay the requests to alert processor 112 in the format understandable by alert processor 112 . In addition, web application 116 may present web pages to the members of collaboration communities, such as product suppliers 120 and users 132 , 134 , 136 , 142 , 144 , 152 , and 154 , receive requests originated from the members, and repackage and/or relay the request s to services component 113 in the format understandable by services component 113 . After alert processor 112 or services component 113 finish processing the requests, web application 116 may receive results from the processing, generate web pages with the results, and present the web pages to the users. Web application 116 and exemplary web pages generated and presented by web application 116 are described in more detail with respect to FIGS. 5A-5D , 6 A- 6 G, 7 - 9 , and 10 A- 10 C. [0037] Customer organizations 130 , 140 , and 150 may subscribe to system 110 for alerts, and may access system 110 using web application 116 , as shown in FIG. 1 Customer organizations 130 , 140 , and 150 may also manage returns, reimbursement, and replacement processes of alerted products. Customer organizations 130 , 140 , and 150 may be any organization that may receive, manage, and/or respond to alerts using system 110 . For example, customer organizations 130 , 140 , and 150 may be hospitals or medical centers that receive product recall alerts in areas such as biomedical devices, blood products, children's consumer product such as toys, food, laboratory products, medical supplies, pharmaceutical products, radiology products, tissues and organs, engineering and facilities related products and devices, and healthcare related hardware and software. In certain embodiments, customer organizations 130 , 140 , and 150 may include a number of facilities, and each facility may receive alerts relevant to its functions only. For example, a facility with a pharmacy department may be interested in receiving product recall alerts in pharmaceutical products while a facility without a pharmacy department may not. [0038] Customer organizations 130 , 140 , and 150 may employ any number of users that may manage and respond to alerts. In certain embodiments, customer organization 130 may employ users 132 , 134 , and 136 , customer organization 140 may employ users 142 and 144 , customer organization 150 may employ users 152 and 154 , as shown in FIG. 1 . In certain embodiments, users 132 , 134 , and 136 may manage and respond to alerts for all facilities within alert subscribing entity 130 while users 142 and 144 may manage and respond to alert for only one facility within alert subscribing entity 140 . In certain embodiments, users 132 , 134 , and 136 may be charged with a single role in managing and responding to alerts while users 142 and 144 may be charged with multiple roles in managing and responding to alerts. For example, user 142 may be charged with a managing role (“manager”) that may require overseeing alert processing within alert subscribing entity 140 . User 142 may also be charged with another role, such as an administrating role (“administrator”) that may require handling administrative tasks, such as entering data into system 110 . [0039] User 134 may be charged with a coordinating role (“coordinator”) that may require assigning alerts to a user charged with a responding role (“responder”). For example, in coordinating alerts, user 134 may assign a product recall alert to user 136 , who may be a responder. The assignment may require user 136 to handle the alert by disposing of the recalled product. Failure to perform assigned roles may trigger an escalation process as described in greater detail with respect to FIG. 4 . Actions that users 132 , 134 , 136 , 142 , 144 , 152 , and 154 may perform through web application 116 may be limited based on the assigned roles. In certain embodiments, however, any of users 132 , 134 , 136 , 142 , and 144 may access and perform any actions to manage returns, reimbursements, and replacements processes of the recalled products. [0040] In certain embodiments where there may be multiple facilities within an alert subscribing entity, a role may be further divided into multiple managing roles to account for the hierarchy within the entity. For example, a managing role within an alert subscribing entity may include an account manager and multiple facilities managers. An account manager may manage all alerts within the alert subscribing entity, and may be responsible for receiving a daily summary of alert activities and workflow within the entity. Each facility within the entity may have a facility manager. A facility manager may manage all alerts within one facility, and may be responsible for receiving a daily summary of alert activities and workflow within the facility only. [0041] System 110 may interface with one or more external system 160 using interface component 118 . In certain embodiments, external system 160 may run outside the firewall of system 110 , and connect to system 110 using one or more ports that are opened by interface component 118 for external system 160 . External system 160 may be any system that interacts with system 110 , for example, to request system 110 to perform a process or obtain data related to alert collection, distribution, management, coordination assignment, and returns, reimbursements, and replacements of alerted products. In certain embodiments, external system 160 may receive a request from system 110 . In response to the request, external system 160 may perform a process and/or send data to system 110 . Data from external system 160 ,,which may otherwise be entered manually into system 110 , may be used in generating web pages of web application 116 although the data may be used for any other purposes. In certain embodiments, external system 160 may be an enterprise resource planning (ERP) system, procurement system, accounting system, inventory system, materials management system, supply chain management system, and/or external database system. [0042] Rather than using web application 116 , customer organization 150 may alternatively receive, manage, and respond to subscribed alerts using external system 160 . In certain embodiments, external system 160 may be any system that provides alert collection, distribution, management, and/or coordination assignment functionalities and/or alerted product returns, reimbursement, and replacement management functionalities using alert processor 112 of system 110 for providing functionalities. For example, external system 160 may retrieve alert data from system 110 , and present the data to users 152 and 154 . To this end, external system 160 may include its own user interface to present the retrieved data to users 152 and 154 and to interact with the users. Through its own user interface, external system 160 may customize the obtained alerts for its alert subscribing customer organizations, such as customer organization 150 . In certain embodiments, external system 160 may be developed or customized to provide alert management and coordination assignment services for a specific industry or a specific segment of an industry that may not conveniently use web application 116 . By being external to system 110 , external system 160 may receive user actions before the actions are received by system 110 . In certain embodiments, external system 160 may modify and/or filter out the user actions in accordance with its own rules that may be more restrictive than ones implemented in system 110 . The user interface of external system 160 may be implemented as a web-based application. To this end, external system 160 may include web servers, application servers, and/or databases. [0043] As shown in FIG. 1 , in some embodiments, interface component 118 may act as a gateway between external system 160 and system 110 . To support external systems developed under multiple technologies, interface component 118 may use a Service Oriented Architecture (SOA), and may be implemented using Common Object Request Broker Architecture (CORBA), Web Service, Simple Object Access Protocol (SOAP), Remote Procedure Call (RPC), Distributed Component Object Model (DCOM), or Windows Communication Foundation (WCF). [0044] Networks 172 , 174 , and 176 may be any type of communication mechanism and may include, alone or in any suitable combination, a telephony-based network, a local area network (LAN), a wide area network (WAN), a dedicated intranet, wireless LAN, the Internet, an Intranet, a wireless network, a bus, or any other communication mechanisms. Further, any suitable combination of wired and/or wireless components and systems may provide networks 172 , 174 , and 176 . Moreover, networks 172 , 174 , and 176 may be embodied using bidirectional, unidirectional, or dedicated communication links. In certain embodiments, networks 172 , 174 , and 176 may be the same. [0045] As shown in FIG. 1 , services component 113 may seamlessly interact with alert processor 112 . In certain embodiments, they may be combined. Services component 113 may interact with alert processor 112 to provide supplier and customer collaboration services. For example, services component 113 may use alert data collected from customer organizations during alert collection, distribution, management, and coordination assignment processes. With access to the data, services component 113 may identify customer organizations that may have been affected by a specific alert, aggregate the data collected from each of the affected customer organizations, etc. In addition, service component 113 , using the data, may identify participating members who may have specific relationships with certain alerts. This may help service component 113 to return more focused and relevant search results when one participating member searches for information. [0046] In certain embodiments, the interaction between alert processor 112 and services component 113 may not be noticeable to members of collaboration communities, such as product supplier 120 and users 132 , 134 , 136 , 142 , 144 , 152 , and 154 . For example, while viewing an alert detail page, such as the web page depicted in FIG. 5D , the member may click a hypertext link. The link may direct the member to a collaboration services web page, such as the alert forum page described in FIG. 6G . After accessing collaboration services, the member may be directed back to the alert detail page. In certain embodiments, a separate web application may provide collaboration services and the member may receive a notice when the member is being directed to a different web application. The notice may help the member to remember that his action, such as comments supplied by the member, may be seen and read by users from other customer organizations, suppliers, etc. [0047] In addition, access restrictions may be implemented between web pages generated in connection with alert processor 112 and collaboration services web pages generated in connection with services component 113 . For example, a non-participating user, such as a user who has opted out of the supplier and customer collaboration services and/or has not joined collaboration communities, may not have access to collaboration services. To this end, a link to collaboration services web pages may not be offered to the non-participating user on the web pages of alert processor 112 . In other embodiments, the non-participating user may receive an offer to join collaboration communities when the non-participating user selects a link to collaboration services web pages. [0048] In certain embodiments, product suppliers, such as product supplier 120 , may have access only to web pages generated in connection with services component 113 . To this end, services component 113 may provide product supplier focused functionalities. For example, by using web pages generated in connection with services component 113 , product supplier 120 may view a list of alerts that product supplier 120 has issued. Product supplier 120 may select a specific alert from the list and view more detailed information about the specific alert. The product supplier functionalities of services component 113 may not be accessible by members from customer organizations. [0049] FIG. 2 illustrates an exemplary alert collection and distribution process 200 . System 110 may obtain alerts, e.g., from multiple sources (step 210 ). For example, system 110 may obtain alerts from websites or other systems. System 110 may monitor the websites and other systems, and obtain alerts automatically when triggering events occur. System 110 may also receive alerts from manufacturer recall notices. System 110 may further receive alerts from its alert subscribing customer organizations, such as customer organizations 130 , 140 , and 150 . Once obtained, the alerts may be reviewed, for example, by a quality control staff, or automatic review process (step 220 ). Upon reviewing the alerts, the reviewer may delete duplicate alerts (step 230 ). System 110 may edit remaining alerts to enhance the quality of alert content (step 240 ). For example, system 110 may add additional information to clarify alerts. The alerts may then be put into a standard format with a consistent set of data elements, and released for distribution to alert subscribing entities (step 250 ). In certain embodiments, the released alerts may be filtered so that only desired alerts may reach each facility within the alert subscribing customer organizations. [0050] FIG. 3 illustrates an exemplary alert management and coordination assignment process 300 . Each facility within alert subscribing entities, such as customer organizations 130 , 140 , and 150 may receive a subscribed alert (step 310 ). A coordinator, such as user 134 , may review the subscribed alert to determine whether it requires a responsive action (step 320 ). Upon review, if user 134 determines that the alert requires no further action (step 320 “No”), user 134 may close the alert (step 360 ). If user 134 determines that the alert requires a responsive action (step 320 “Yes”), user 134 may assign the alert to a responder, such as user 136 (step 330 ). User 136 may perform a task or tasks in response to the alert (step 340 ). For example, user 136 may dispose of any recalled products in response to a product recall alert. After user 136 completes the task(s), user 136 may record actions performed in system 110 , e.g., by using web application 116 (step 350 ). User 134 may then close the alert (step 360 ). In certain embodiments, users may be notified by an e-mail at the completion of the step. For example, when a responder completes an action in response to an alert, a coordinator may receive an automatic e-mail notification via system 110 . [0051] FIG. 4 depicts an exemplary alert escalation process 400 . As shown in FIG. 4 , process 400 may comprise three phases. Phase 1 depicts a stage in alert management and coordination process 300 where an alert has been released to an alert subscribing entity. A coordinator who is assigned to the alert may have a specified number of days to take an action, for example by closing the alert or assigning the alert to a responder to handle the alert. In cases where the coordinator fails to take any action within the specified number of days, the alert may be escalated to a facility manager as shown in FIG. 4 . The facility manager may have a specified number of days to take an action, for example, by reminding the coordinator of the alert or reassigning the alert to a different coordinator. If the facility manager fails to take an appropriate action within the specified number of days, the alert may be escalated to an account manager. [0052] Phase 2 depicts a stage in alert management and coordination process 300 where the alert has been assigned to a responder. The responder has a specified number of days to take an action to handle the alert, for example, by disposing of alerted products and/or returning alerted products to a manufacturer, and record the actions performed. In cases where the responder fails to take an appropriate action within the specified number of days, the alert may be escalated to a facility manager as shown in FIG. 4 . Similar to Phase 1 , the facility manager may have a specified number of days to take an action. If the facility manager fails to take an appropriate action within the specified number of days, the alert may be escalated to an account manager. [0053] Phase 3 depicts a stage in alert management and coordination process 300 where the alert has been handled by a responder and the action performed has been recorded. The coordinator who is assigned to the alert has a specified number of days to close the alert. In cases where the coordinator fails to close the alert within the specified number of days, the alert may be escalated to a facility manager as shown in FIG. 4 . The facility manager may have a specified number of days to take an action. Failure to taken an action by the facility manager may escalate the alert to an account manager. [0054] FIGS. 5A-5D depict screen displays of exemplary web pages generated and presented by exemplary web application 116 of system 110 . A user may log into web application 116 and see a welcome page, as shown in FIG. 5A . The left column of the welcome page may display quick links, and the center column of the page may display alert and recall related news or information. The right column of the page may display a summary and status of currently open alerts that may require the user's action. For example, for the user “Carl Jones,” an alert status shows that the user is a coordinator for five (5) alerts, with zero (0) alert as a responder or manager. As shown in the legend, colors or other indicators may show delayed or escalated alerts. [0055] On the list page shown in FIG. 5B , the user may see a list of the alerts that may require the user's action. The screen may include alert ID with alert release date, alert type, domain, description and manufacturer of the product being alerted, reason for alert, distribution of the alert, alert stage, and alert status. The user may take an action, such as closing the alert, on this screen. [0056] On the detail page shown in FIG. 5C , the user may see more detailed information about one of the alerts listed on the list screen shown in FIG. 5B . The detail information may include, in addition to the information shown in the list screen, comments by an alert analyst, source alert type, source type, detail product information, and work assignments information. The detail page may include links to perform several actions, for example, in the left column as shown in FIG. 5C . In certain embodiments, the links may include “ASSIGN RESPONSE,” “REASSIGN COORDINATOR,” “ADD WORK NOTE,” “SEND FYI E-MAIL,” “CLOSE COORDINATION,” and “RETURN INFORMATION” links. The “RETURN INFORMATION” link may direct the user to web pages that may facilitate the user to manage returns, reimbursement, and replacement processes of alerted products. Exemplary returns, reimbursements, and replacements management and processes of alerted products are illustrated in commonly owned U.S. patent application Ser. No. 12/071,101. [0057] On the detail page 500 D shown in FIG. 5D , the user may see detailed information about another alert; for example, Alert No. 2009030237 . Detail page 500 D may include links that may be different from the links included on the detail page of FIG. 5C . For example, detail page 500 D may include “Community Connect” and/or “Alert Forum” links. The “Community Connect” and “Alert Forum” links enable the user to access collaboration services, e.g., web page generated in connection with services component 113 . Although detail page 500 D shows hypertext links used to provide collaboration services to the user, other mechanisms, such as meta redirect, script language, and network programming, may also be used. [0058] FIGS. 6A-6G are screen displays of web pages generated and presented by a web application of exemplary supplier and customer collaboration services consistent with embodiments of the present invention. When the user clicks on the “Community Connect” link on detail page 500 D, the user may be directed to an About Community Connection page, as shown in FIG. 6A . The About Community Connection page may present the user with a description of services that the community connection may provide. In certain embodiments, the About Community Connection page may act as a portal or home page for collaboration services. To this end, the About Community Connection page may present the user with a list of actions that the user may take. For example, the user may select “JOIN,” as shown in FIG. 6A , to become a member of the community connection. When this option is chosen, the user may be asked to go through a registration process, which may ask the user to read terms and conditions of the services and accept them. A confirmation e-mail may be sent to the user after the registration. In addition, a notification of new member registration may be sent to a community manager. A community manager may monitor and facilitate activities taking place in the community connection to enhance member collaboration experience. In other embodiments, the user of system 110 may be automatically registered to the community connection services by virtue of being a user of system 110 . The user may then be given an opportunity to opt out of the services. [0059] From the About Community Connection page of FIG. 6A , the user may choose to view and edit his profile by clicking “MY PROFILE” on the top right side of the page. Clicking “MY PROFILE” may direct the user to a My Profile page, as shown in FIG. 6B . The user may choose to edit portions of the profile by clicking “Edit Profile” button shown in FIG. 6B , which may direct the user to an edit my profile page as shown in FIG. 6C . In certain embodiments, alert processor 112 and services component 113 may share same profile data for the same user so that the user may not need to manage his profile in multiple locations. To this end, the profile may be inclusive to support both alert processor 112 and services component 113 . In other embodiments, services component 113 may have its own profile data that may be specific to collaboration services. [0060] As shown in FIGS. 6B and 6C , the profile may include the user's name, contact information, role in alert handling and management, preference to receive an alert notification, list of e-mails of FYI recipients, etc. In addition, the profile may include information about a customer organization associated with the user. In certain embodiments, the user may be able to opt-in and opt-out of the community connection services using a check box, as shown in FIG. 6C . [0061] Although it is not shown in FIGS. 6B and 6C , the profile, in certain embodiments, may include further information about the user and the user's preferences in using collaboration services. For example, the information about the user may include data related to the user's level of experience, responsibility, or expertise in handling alerts and/or in alerted products. The user's preferences may include the user's preferred communication channels, time for such communication, etc. In addition, the user may restrict, using the profile, his availability and/or the accessibility of his comments or postings. For example, the user may desire to block certain members from contacting the user. Likewise, the user may desire to block certain members from viewing the user's comments or postings. The restrictions may be accomplished by setting his preferences in the profile. In certain instances, the user may desire to filter out certain members when the user searches for an expert. Likewise, the user may desire to filter out comments and postings supplied by certain members. In certain embodiments, the restriction and filtering may be achieved at the customer organization level. [0062] Once the user becomes a member of the community, the user may choose option # 2 , “Find Members,” from the list of options on the About Community Connection page of FIG. 6A . This option may direct the searching member to a Find Member page as shown in FIG. 6D . Using the Find Member page of FIG. 6D , the searching member may provide search criteria, and get search results back with a list of members that match the search criteria. For example, as shown in FIG. 6D , the searching member may search by the first or last name of a community connection member, the name and address of customer organization, such as hospital name and city and state where the hospital is located, alert handling role, product domain, etc. The search results may be provided to the searching member, for example, on a search results page as shown in FIG. 6E . The search results page of FIG. 6E shows one member matching the search criteria. The name of the matching member may be presented as a hypertext link so that the searching member may click on the link if the searching member desires to contact the matching member. [0063] The searching member may alternatively choose option # 3 , “Connect” from the list of options on the About Community Connection page of FIG. 6A to contact the matching member. The searching member may be presented with a send e-mail page as shown in FIG. 6F . In certain embodiments, the contact information of the matching member may be hidden from the searching member so that the searching member may not be able to communicate with the matching member outside the communication channels provided by the community connection. For example, as shown in FIG. 6F , the searching member may type in, without knowing the matching member's contact information, the subject and message of the e-mail, and click “OKAY” button to send the e-mail to the matching member. Limiting communications to the community connection provided channels may protect privacy of the members. In certain embodiments, product supplier 120 may also become a member of community connection. Product supplier 120 may search for members and contact matching members using the community connection services. In addition, product supplier 120 may be identified by search and contacted by other members of community connection. [0064] When the user of system 110 clicks on the “Alert Forum” link on detail page 500 D, the user may be directed to an alert forum page, as shown in FIG. 6G . The Alert Forum may provide a forum for the users to discuss and share information, e.g., related to a specific alert. For example, as shown on the alert forum page of FIG. 6G , the users may discuss and share information by posting comments related to Alert No. 2009030237 on a message board. The users may rate the comments posted by other users, and the average rating may be calculated and presented as shown in FIG. 6G . In certain embodiments, the alert forum page of FIG. 6G may be accessible to only community connection members. In other embodiments, the alert forum page of FIG. 6G may be accessible to all users of system 110 who have access to detail page 500 D. In certain embodiments, certain users may have read permission without write permission. For example, certain users may be able to read the comments posted by other users, but may not be allowed to post their own comments. Although a message board is shown in FIG. 6G , other mechanisms, such as wiki collaboration and chat rooms, may be used to support the alert forum features. [0065] FIG. 7 is a context diagram illustrating exemplary interactions among components in an exemplary alert distribution and management system with supplier and customer collaboration services consistent with embodiments of the present invention. FIG. 7 depicts communications with collaborative alert system 110 . As indicated by arrow 712 , system 110 may receive direct recall information from a product supplier 720 , such as a manufacturer, supplier, and/or distributor. Receiving recall information from product supplier 720 may be, for example, part of step 210 of alert collection and distribution process 200 , which is described in more detail with respect to FIG. 2 . System 110 may process the received recall information, e.g., according to steps 220 - 240 of alert collection and distribution process 200 . As indicated by arrows 731 , 741 , and 742 , system 110 may distribute the processed information as recall alerts to customer organizations 730 , 740 , and 750 . Distributing recall alerts to customer organizations 730 , 740 , and 750 may be, for example, part of step 250 of alert collection and distribution process 200 . [0066] Customer organizations 730 , 740 , and 750 may manage received recall alerts, for example, according to alert management and coordination assignment process 300 , described in more detail with respect to FIG. 3 . Customer organizations 730 , 740 , and 750 may record the actions taken to handle the recall alerts according to step 350 of alert management and coordination assignment process 300 . As indicated by arrows 732 , 742 , and 752 , recorded actions and other remediation data, may be provided to system 710 . [0067] In addition, each of customer organizations 730 , 740 , and 750 communicate with system 110 , for example using a reply form, such as an E-Reply Form shown in FIG. 8 . Some of the data on the reply form of FIG. 8 may be pre-populated by system 110 , as shown in FIG. 8 . For example, name, product ID, and Lot/Serial information of alerted product, account name, and name and title of the user may be pre-populated as shown in FIG. 8 . Customer organizations 730 , 740 , and 750 may only need to provide fields such as an account number, packaging, and quantity information to complete the form. In addition, customer organizations 730 , 740 , and 750 may optionally provide notes to product supplier 720 . Packaging and quantity may represent how products are packaged and how many products are located at the customer organizations. [0068] System 110 may process the remediation data including data provided by customer organizations 730 , 740 , and 750 through reply forms, such as the E-Reply Form of FIG. 8 . System 110 may present aggregated remediation data to product supplier 720 , as indicated by arrow 722 in FIG. 7 . In certain embodiments, aggregated data from customer organizations 730 , 740 , and 750 may be presented to product supplier 720 on a reply report, such as the exemplars E-Reply Report shown in FIG. 9 . For example, the E-Reply Report of FIG. 9 shows a list containing data from several customer organizations, such as Wellpoint and Health Center. In addition, product supplier 720 may generate various types of historical report based on aggregated remediation data. Several examples of reports that may be generated by product supplier 720 may include alerts count, alerts by domain, and alerts by agency, as shown in FIGS. 10A-10C . The reports may be generated for different time periods, customer organizations, products, etc. For example, the historical reports of FIGS. 10A-10C show yearly data. The generated reports and remediation data may be used to prepare a report or reply card for a government or regulatory agency 770 , such as Food and Drug Administration (FDA). Reports could also be made to other entities, such as parent companies of customer organizations, insurance carriers, public, etc. [0069] FIG. 11 is a context diagram illustrating exemplary interactions among members of collaboration communities in an exemplary alert distribution and management system with supplier and customer collaboration services consistent with embodiments of the present invention. Members of collaboration communities may be, at times, content providers, such as content providers 1110 , 1120 , and 1130 , and subscribing members, such as subscribing members 1160 , 1170 , 1180 , and 1190 . Content providers 1110 , 1120 , and 1130 may include members from product supplier 720 , industry experts, members from customer organizations 730 , 740 , or 750 who are experts in handling specific alerts, etc. Subscribing members may include members from product suppliers and/or customer organizations who seek content, such as help responding to an alert, access to repair protocols, etc. As shown in FIG. 11 , content providers 1110 , 1120 , and 1130 and subscriber members 1160 , 1170 , 1180 , and 1190 may collaborate using a variety of communication channels provided by system 110 . The communication channels may include any communication channels that may be supported by network 172 . For example, the communication channels may include chat rooms, live meetings, wiki collaboration, video training, etc. [0070] One of ordinary skill in the art will recognize that while some of the drawings illustrate steps performed in a particular order, the order in which the steps are carried out is irrelevant. Systems consistent with the invention may carry out the steps in any order or in some cases combine or omit one or more steps without departing from the scope of the present disclosure. [0071] Other embodiments of the invention will be apparent to those skilled in the art from consideration of the specification and practice of the invention disclosed herein. For example, the collaboration environment of FIG. 11 may include more or fewer content providers and/or subscribing members. It is intended that the specification and examples be considered as exemplary only, with a true scope and spirit of the invention being indicated by the following claims.

A method for managing remediation of alerted products implemented using a computer having a processor and a display device is provided. The method comprises identifying an alert related to a product. The method also comprises facilitating handling of the alert by a user of the product. The method further comprises receiving data related to alert handling from the product user. The method further comprises analyzing the data related to alert handling with other data related to the alert. The method further comprises displaying the analyzed data on the display device. The method further comprises, based on the analyzed data, monitoring remediation efforts related to the alert.

CROSS-REFERENCES TO RELATED APPLICATIONS This application claims priority to, and incorporates by reference herein in its entirety, pending U.S. Provisional Patent Application Ser. No. 60/491,649, filed 31 Jul. 2003. BACKGROUND U.S. Pat. No. 4,674,049 (Kubo), which is incorporated by reference herein in its entirety, allegedly cites an “anti-skid brake control system for an automotive vehicle has a control module comprising one or more microcomputers. The microcomputer is connected to a wheel speed sensor, which supplies a sensor signal indicative of the wheel speed, and a timer which outputs a timer signal indicative of the elapsed time. The microcomputer has an input time data sampling program for latching the timer signal value and storing the latched timer signal value as input time data for the corresponding sensor signal pulse. The input time data sampling program is executed as an interrupt program independent of a main program which processes the input time data and controls application and release of hydraulic braking pressure to a vehicle wheel in such a manner that wheel speed is adjusted toward an optimum relationship with vehicle speed. The microcomputer is also provided with a flag register which is incremented everytime the main program is interrupted for execution of the input time data sampling program and decremented at the end of each cycle of execution of the main program. The microcomputer repeatedly executes the main program until the register value of the flag register becomes equal to zero.” See Abstract. U.S. Pat. No. 4,964,047 (Matsuda), which is incorporated by reference herein in its entirety, allegedly cites an “anti-skid brake control system employs a technique for correcting a longitudinally based vehicular speed variation gradient by a road slop dependent correction value. The road slop dependent correction value is derived on the basis of an assumed road slop condition which is assumed on the basis of magnitude of increase of the braking pressure.” See Abstract. SUMMARY Certain exemplary embodiments comprise a method comprising: receiving a measurement of a vehicle speed; receiving information indicative of a drive speed; comparing a value related to the measurement of the vehicle speed with the information indicative of the drive speed to obtain a first speed deviation metric; and controlling a torque output of the drive within a limited range, the limited range at least partially based upon the first speed deviation metric. BRIEF DESCRIPTION OF THE DRAWINGS A wide variety of potential embodiments will be more readily understood through the following detailed description, with reference to the accompanying drawings in which: FIG. 1 is a block diagram of an exemplary embodiment of a slip-slide control system 1000 ; FIG. 2 is a flow diagram of an exemplary embodiment of a slip-slide control method 2000 ; and FIG. 3 is a block diagram of an exemplary embodiment of an information device 3000 . DEFINITIONS When the following terms are used herein, the accompanying definitions apply: actual—based in reality. An actual value can be estimated via measurement. comparator—a device adapted to compare a measured property of an object with a standard and/or another measured property of the object. controller—a device for processing machine-readable instruction. A controller can be a central processing unit, a local controller, a remote controller, parallel controllers, and/or distributed controllers, etc. The controller can be a general-purpose microcontroller, such the Pentium III series of microcontrollers manufactured by the Intel Corporation of Santa Clara, Calif. In another embodiment, the controller can be an Application Specific Integrated Circuit (ASIC) or a Field Programmable Gate Array (FPGA) that has been designed to implement in its hardware and/or firmware at least a part of an embodiment disclosed herein. correct—adjust in value. Doppler effect—a change in an observed frequency of a wave, as of sound or light, occurring when the source and observer are in motion relative to each other. drive—a means by which power is transmitted to the wheels of a vehicle. electric motor—a motor powered by electricity. An electric motor can comprise two wound members, one stationary, called the stator, and the other rotating, called the rotor. forward direction—a course advancing an object. information—data. information device—any device capable of processing information, such as any general purpose and/or special purpose computer, such as a personal computer, workstation, server, minicomputer, mainframe, supercomputer, computer terminal, laptop, wearable computer, and/or Personal Digital Assistant (PDA), mobile terminal, Bluetooth device, communicator, “smart” phone (such as a Handspring Treo-like device), messaging service (e.g., Blackberry) receiver, pager, facsimile, cellular telephone, a traditional telephone, telephonic device, a programmed microprocessor or microcontroller and/or peripheral integrated circuit elements, an ASIC or other integrated circuit, a hardware electronic logic circuit such as a discrete element circuit, and/or a programmable logic device such as a PLD, PLA, FPGA, or PAL, or the like, etc. In general any device on which resides a finite state machine capable of implementing at least a portion of a method, structure, and/or or graphical user interface described herein may be used as an information device. An information device can include well-known components such as one or more network interfaces, one or more processors, one or more memories containing instructions, and/or one or more input/output (I/O) devices, one or more user interfaces, etc. I/O device—any sensory-oriented input and/or output device, such as an audio, visual, haptic, olfactory, and/or taste-oriented device, including, for example, a monitor, display, projector, overhead display, keyboard, keypad, mouse, trackball, joystick, gamepad, wheel, touchpad, touch panel, pointing device, microphone, speaker, video camera, camera, scanner, printer, haptic device, vibrator, tactile simulator, and/or tactile pad, potentially including a port to which an I/O device can be attached or connected limited range—a constrained extent of values. measurement—a dimension, quantification, and/or capacity, etc. determined by observation. mine haul truck—a motor vehicle adapted to haul ore extracted from the earth. motor—something that produces or imparts motion. reversing directions—switching from a clockwise to a counterclockwise rotation, or vice versa. rotational direction—a course upon which an object turns around a center or an axis. A rotational direction can be expressed as being, for example, clockwise or counterclockwise relative to a frame of reference. rotational speed—a velocity at which an object turns around a center or an axis. A rotational speed can be expressed in terms of a number of revolutions in a given time period. sharpness—acuteness. slip—lose traction. speed—a transverse or rotational velocity. steering encoder—a device adapted to detect, store, and/or transmit the sharpness of a vehicular turn. tachometer—an instrument used to measure the rotations per unit time period of a rotating shaft truck—a motor vehicle designed for carrying or pulling a load. turn—to change the position of by traversing an arc. value—a definable quantity. velocimeter—a device adapted to measure a traversing speed. vehicle—a device or structure for transporting persons or things. A vehicle can be a car, truck, locomotive, and/or mine haul truck, etc. wheel—a solid disk or a rigid circular ring connected by spokes to a hub, designed to turn around an axle passed through the center. DETAILED DESCRIPTION FIG. 1 is a block diagram of an exemplary embodiment of a slip-slide control system 1000 . Certain exemplary embodiments can comprise a vehicle 1100 . Vehicle 1100 can be an automobile, a pick-up truck, a tandem wheel truck, and/or a mine haul truck, etc. Vehicle 1100 can comprise a first wheel drive 1200 and a second wheel drive 1300 . In certain exemplary embodiments, first wheel drive 1200 can comprise a first motor 1250 . Second wheel drive 1300 can comprise a second motor 1350 . In certain exemplary embodiments, first wheel drive 1200 and second wheel drive 1300 can be driven by a single electric or fossil fuel powered engine. First wheel drive 1200 can be controllably rotatable at a first drive speed. Second wheel drive 1300 can be controllably rotatable at a second drive speed. The first drive speed can be distinct and/or different from the second drive speed. In certain exemplary embodiments, the first drive speed and/or the second drive speed a can be controllable via a pneumatic or hydraulic braking system. First motor 1250 , second motor 1350 can be alternating current (AC) electric induction motors, direct current (DC) electric motors, and/or hydraulically powered motors, etc. The speed of first motor 1250 and/or second motor 1350 can be controlled via an ac inverter frequency controller, a silicon controlled rectifier speed control circuit, and/or a variable speed hydraulic motor, etc. In certain exemplary embodiments, first wheel drive 1200 and second wheel drive 1300 can be driven by a single motor. The first drive speed and/or the second drive speed can be controllable via a braking system. First drive 1200 and/or second drive 1300 can comprise tachometers such as a tachometer 1275 and a tachometer 1375 . Tachometer 1275 and/or tachometer 1375 can be adapted to provide a rotational frequency of a particular shaft associated with first drive 1200 and/or second drive 1300 . Tachometer 1275 and tachometer 1375 can, for example, be adapted to directly or indirectly determine an actual first drive speed and/or an actual second drive speed. Tachometer 1275 and/or tachometer 1375 can be direct contact tachometers using, for example, magnetic brushes to provide a signal indicative of rotational speed. Tachometer 1275 and/or tachometer 1375 can be indirect contact tachometers adapted to sense an optical signal reflected off a surface. Vehicle 1100 can comprise a velocimeter 1400 adapted to measure an actual speed of vehicle 11100 relative to the earth. In certain exemplary embodiments, velocimeter 1400 can utilize Doppler effect shifts of optical and/or acoustic waves to determine the actual speed of vehicle 1100 . In certain exemplary embodiments velocimeter 1400 can utilize a triangulation technique using signals from a plurality of reference points to measure an actual speed of vehicle 1100 relative to the earth. The measured actual speed of vehicle 1100 can be utilized to estimate an expected first drive speed and/or an expected second drive speed. Vehicle 1100 can comprise a steering encoder 1450 . Steering encoder 1450 can be adapted to detect, determine, receive, and/or transmit a value indicative of a turn sharpness associated with vehicle 1100 . The turn sharpness can be used to correct an actual vehicle speed measured by velocimeter 1400 , the actual first drive speed, and/or the actual second drive speed, etc. Vehicle 1100 can comprise a first comparator 1500 and a second comparator 1700 . Comparator 1500 can be adapted to compare the actual first drive speed with the expected first drive speed. Comparator 1700 can be adapted to compare the actual second drive speed with the expected second drive speed. In certain exemplary embodiments, a single physical device can comprise comparator 1500 and comparator 1700 . Vehicle 1100 can comprise a first controller 1600 and a second controller 1800 . Controller 1600 can be adapted to control the actual first drive speed within a limited range. Controller 1800 can be adapted to control the actual second drive speed within a limited range. In certain exemplary embodiments, controller 1600 can be adapted to control the actual torque of first wheel drive 1200 within a limited range. Controller 1800 can be adapted to control the actual torque of second wheel drive 1300 within a limited range. In certain exemplary embodiments, a single physical device can comprise controller 1600 and controller 1800 . In certain exemplary embodiments, controller 1600 can be adapted to control the actual first drive speed within a range of, for example, approximately 60% and approximately 100% of the expected first drive speed. Likewise, in certain exemplary embodiments, controller 1800 can be adapted to control the actual second wheel drive speed within a range of, for example, approximately 60% and approximately 100% of the expected second drive speed. Controller 1600 and/or controller 1800 can be adapted to prevent first wheel drive 1200 from turning in a rotational direction counter to second wheel drive 1300 . Preventing first wheel drive 1200 from turning in the rotational direction counter second wheel drive 1300 can improve the operational life of at least one mechanical component of first wheel drive 1200 and/or second wheel drive 1300 such as, for example, a differential of vehicle 1100 . The differential of vehicle 11100 can be adapted to allow the first drive speed to be distinct and/or different from the second drive speed. FIG. 2 is a flow diagram of an exemplary embodiment of a slip-slide control method 2000 , which can be used for improving vehicular performance and/or reliability. At activity 2100 , a determination can be made of a measurement of an actual speed of a vehicle. The measurement can utilize what is known as the Doppler effect and/or Doppler shift. In certain exemplary embodiments, the Doppler shift detected by a Doppler transceiver can be standardized and/or calibrated to a particular constant, such as 100 Hz per mile per hour (MPH) of vehicle speed. The Doppler shift of the reflected Doppler transmission signal can be proportional to the change in distance over time between the point at which the Doppler transmission signal was directed and the Doppler transceiver. An offset angle can be defined between the direction of the Doppler transmission signal and the direction of travel of the vehicle. In certain exemplary embodiments, the speed of the vehicle in its direction of travel can be calculated by multiplying a value proportional to the Doppler frequency shift by a cosine of the offset angle. Multiplying the value proportional to the Doppler frequency shift by the cosine of the offset angle can provide, for the velocity vector detected by the Doppler shift, the component of that velocity vector that is aligned with the direction of travel of the vehicle. In certain exemplary embodiments, for example, the speed of a vehicle can be calculated as: actual speed=Doppler shift/(100 Hz/MPH)/cos (offset angle). In certain exemplary embodiments, for example, the speed of a vehicle can be calculated as: actual speed=Doppler shift/cos (offset angle)/(100 Hz/MPH). In an exemplary embodiment with a 30 degree offset angle and a measured Doppler shift of 1732 Hz: Actual speed=1732/(100 Hz/MPH)/cos(30)=20 MPH The Doppler signal can be reflected off, for example, a road surface, a mine wall face, and/or a ground surface adjacent to the road surface, etc. A reflected Doppler signal can be detected and the detected information can be processed. The detected information can be processed to filter signals reflected off unintended surfaces, noise, interference, harmonics, etc. The vehicle can comprise a first wheel drive and a second wheel drive. The first wheel drive can comprise a first electric motor. The first wheel drive can be controllably rotatable at a first drive speed. The vehicle can comprise a second wheel drive. The second wheel drive can comprise a second electric motor. The second motor can be distinct from the first motor. The second wheel drive can be controllably rotatable at a second drive speed. The second drive speed can be distinct from the first drive speed. At activity 2200 , actual drive speeds can be determined. The actual drive speeds can comprise an actual first drive speed associated with the first wheel drive and/or an actual second drive speed associated with the second wheel drive. The actual drive speeds can be determined, for example, via at least one tachometer. At activity 2300 , a turn sharpness can be detected and/or determined. The turn sharpness can be indicative of a degree of acuteness at which the vehicle is changing directions. The turn sharpness can be detected, determined, and/or transmitted via a steering encoder. At activity 2400 , the measurement of the actual vehicle speed can be received. Receiving the measurement of the actual vehicle speed can allow an information device to calculate, compare, and/or control values to assist in controlling vehicular wheel slippage and sliding conditions. At activity 2500 , information indicative of the actual first drive speed and the actual second drive speed can be received. The information indicative of the actual first drive speed and the actual second drive speed can be received directly from a speed sensing device and/or via transmission from an information device. At activity 2600 , the turn sharpness can be received. The turn sharpness can be received, for example, from the steering encoder. Turn sharpness can be expressed, for example, as a percentage wherein a vehicle bearing in a forward direction and not turning can be expressed as 50% on a 0 to 100% scale. Maximum left turn sharpness can be expressed as 0%. Maximum right turn sharpness can be expressed as 100%. Alternatively, maximum right turn sharpness can be expressed as 0%, and maximum left turn sharpness can be expressed as 100%. Alternatively, any other scale can be utilized. At activity 2700 , expected drive speeds can be determined. For example, an expected first drive speed associated with the first drive can be determined. An expected second drive speed associated with the second drive can be determined. The expected drive speeds can be calculated using the measurement of the actual speed of the vehicle. The expected drive speeds can be calculated using wheel circumference via a determination indicating the number of wheel revolutions approximating the measured actual speed of the vehicle. At activity 2800 , the vehicle and/or drive speeds can be corrected for turn sharpness For example, exemplary multiplicative factors for correcting the measurement of the actual speed of the vehicle are shown in Table 1. Exemplary factors for correcting the actual first drive speed and the actual second drive speed are shown in Table 2. TABLE 1 Steering Encoder (%) Factor 0 0.95 10 0.96 20 0.97 30 0.98 40 0.99 50 1.0 60 0.99 70 0.98 80 0.97 90 0.96 100 0.95 TABLE 2 Steering Factor 1 for first Factor 2 for second Encoder (%) wheel drive wheel drive 0 1.0 1.0 10 0.966 1.044 20 0.900 1.050 30 0.820 1.040 40 0.722 1.001 50 0.642 0.963 60 1.044 0.966 70 1.05 −0.900 80 1.040 0.820 90 1.001 0.722 100 0.963 0.642 At activity 2850 , at least one expected drive speed and at least one actual drive speed can be compared. Comparing at least one expected drive speed with the at least one actual drive speed can provide information indicative of whether a wheel drive is slipping and/or sliding on a surface. A speed deviation metric can be obtained via comparing at least one expected drive speed at least one actual drive speed. The speed deviation metric can be information indicative of whether a wheel drive is slipping and/or sliding on a surface. The speed deviation metric can provide information adaptable for use in improving the control, reliability, and/or safety of a vehicle. At activity 2900 , at least one drive speed can be controlled the speed controlled can be the first drive speed and/or the second drive speed. At least one drive speed can be controlled via a frequency controller associated with the first electric motor and/or the second electric motor. In certain exemplary embodiments, at least one drive speed can be controlled to prevent the first drive from rotating in a direction counter to the direction of the second drive. Preventing the first drive from rotating in a direction counter to the direction of the second drive can improve the life of mechanical power transmission equipment comprised in the first drive and/or the second drive such as, for example, a differential. At activity 2950 , the torque applied to at least one drive can be controlled. In certain exemplary embodiments, the torque applied to at least one drive can be controlled via controlling a torque output of the first electric motor and/or the second electric motor. Controlling the torque applied to at least one drive can improve the control of the vehicle when the vehicle is slipping and/or sliding. In certain exemplary embodiments, controlling the torque applied to at least one drive speed can prevent the first drive from rotating in a direction counter to the direction of the second drive. FIG. 3 is a block diagram of an exemplary embodiment of an information device 3000 , which in certain operative embodiments can comprise, for example, comparator 1500 , comparator 1700 , controller 1600 , controller 1800 of FIG. 1 . Information device 3000 can comprise any of numerous well-known components, such as for example, one or more network interfaces 3100 , one or more processors 3200 , one or more memories 3300 containing instructions 3400 , one or more input/output (I/O) devices 3500 , and/or one or more user interfaces 3600 coupled to I/O device 3500 , etc. In certain exemplary embodiments, via one or more user interfaces 3600 , such as a graphical user interface, a user can provide a telecommunications address of a user-associated telecommunications device of interest and/or can receive current location information concerning the user-associated telecommunications device of interest. Still other embodiments will become readily apparent to those skilled in this art from reading the above-recited detailed description and drawings of certain exemplary embodiments. It should be understood that numerous variations, modifications, and additional embodiments are possible, and accordingly, all such variations, modifications, and embodiments are to be regarded as being within the spirit and scope of the appended claims. For example, regardless of the content of any portion (e.g., title, field, background, summary, abstract, drawing figure, etc.) of this application, unless clearly specified to the contrary, there is no requirement for the inclusion in any claim of the application of any particular described or illustrated activity or element, any particular sequence of such activities, or any particular interrelationship of such elements. Moreover, any activity can be repeated, any activity can be performed by multiple entities, and/or any element can be duplicated. Further, any activity or element can be excluded, the sequence of activities can vary, and/or the interrelationship of elements can vary. Accordingly, the descriptions and drawings are to be regarded as illustrative in nature, and not as restrictive. Moreover, when any number or range is described herein, unless clearly stated otherwise, that number or range is approximate. When any range is described herein, unless clearly stated otherwise, that range includes all values therein and all subranges therein. Any information in any material (e.g., a United States patent, United States patent application, book, article, etc.) that has been incorporated by reference herein, is only incorporated by reference to the extent that no conflict exists between such information and the other statements and drawings set forth herein. In the event of such conflict, including a conflict that would render a claim invalid, then any such conflicting information in such incorporated by reference material is specifically not incorporated by reference herein.

Certain exemplary embodiments comprise a method comprising: receiving a measurement of a vehicle speed; receiving information indicative of a drive speed; comparing a value related to the measurement of the vehicle speed with the information indicative of the drive speed to obtain a first speed deviation metric; and controlling a torque output of the drive within a limited range, the limited range at least partially based upon the first speed deviation metric.

RELATED APPLICATIONS [0001] This application is a continuation of U.S. application Ser. No. 11/401,153 filed Apr. 10, 2006 which is a continuation of U.S. application Ser. No. 10/991,876 filed Nov. 18, 2004, now U.S. Pat. No. 7,029,926, issued on Apr. 18, 2006, which is a divisional of U.S. application Ser. No. 10/651,619, filed Aug. 29, 2003, now U.S. Pat. No. 7,020,004, issued on Mar. 28, 2006, all which are hereby incorporated by reference in their entireties herein. BACKGROUND OF THE INVENTION [0002] 1. Field of the Invention [0003] The present invention relates to semiconductor processing technology and, in particular, concerns a device and a fabrication process, whereby a magnetic memory structure may be formed. [0004] 2. Description of the Related Art [0005] Magnetic memory is a developing technology that offers the advantages of non-volatile memory with high-density fabrication. Magnetic memory structures, such as magneto-resistive random access memory (MRAM), manipulate the magnetic properties of layered magneto-resistive materials to produce a selective resistance differential across the magnetic memory structure. In one aspect, magnetic memory structures utilize selective resistance by controlling the alignments of spin states within multiple layers of material to increase or decrease the resistance of a material. Selectively altering the spin states of magneto-resistive materials results in selectively altering the resistance of the magnetic memory structure, which may be sensed thereby permitting the use of layered magneto-resistive materials in logic state devices. [0006] Conventional magnetic memory devices may comprise a stacked structure that may include a hard (high coercivity) layer, a soft (low coercivity) layer, and a non-magnetic layer interposed therebetween. The soft or sense layer may be programmed through the application of proximate magnetic field and the net magnetization vectors between the programmable layer and the hard layer may be changed between two discrete quantities, which may then be sensed to detect the programmed logic state of the magnetic memory device. [0007] Additionally, magnetic memory devices, including MRAM, may also be referred to as a magnetic memory bit. Magnetic memory bits may utilize various technologies associated with at least one of, but is not limited to an anisotropic magnetoresistance (AMR) bit, a giant magnetoresistance (GMR) bit, a pseudo-spin valve (PSV) bit, and a spin-dependent tunneling (SDT) bit. A plurality of magnetic memory bits and the conductors that influence and/or access the magnetic memory bits may be arranged in a grid array, which may be formed on a semiconductor substrate layer, such as silicon. In a grid array, magnetic memory bits may be positioned adjacent one another and arranged on the substrate so as to be co-planar. [0008] Due to the co-planar arrangement of conventional magnetic memory bits in a magnetic memory grid array, the areal density of the magnetic memory bits within the substrate plane is bounded by at least the amount of planar space available on the upper surface of the substrate. Other factors that may contribute to limiting density of conventional magnetic memory bits include physical size of the magnetic memory bits and the level at which fringe magnetic fields affect neighboring magnetic memory bits. Therefore, there exists a need to increase the fabrication density of magnetic memory bits, devices and/or structures without adversely affecting the performance, reliability, and functionality of the magnetic memory bits, devices, and/or structures. SUMMARY OF THE INVENTION [0009] The aforementioned needs may be satisfied by a memory device comprising, in one embodiment, a substrate having a first surface, a first memory layer having a first programmable component formed on the first surface of the substrate, wherein the first memory layer can be configured to store a first logic state therein by selective magnetization of the first programmable component, and a second memory layer having a second programmable component formed above the substrate in a manner so as to overlie the first memory layer, wherein the second memory layer can be configured to store a second logic state therein by selective magnetization of the second programmable component, and wherein the second memory layer increases the storage density of the memory device. [0010] In one aspect, the memory device may further comprise a first plurality of electrodes that are formed in the first memory layer and electrically interconnected to the first programmable component and a second plurality of electrodes that are formed in the second memory layer and electrically interconnected to the second programmable component. Also, the first plurality of electrodes may comprise a conductive material that generates a first magnetic field when electrical current passes through the first plurality of electrodes. The second plurality of electrodes comprise a conductive material that generates a second magnetic field when electrical current passes through the second plurality of electrodes. [0011] In addition, the memory device may further comprise a word line that is formed between and proximate to the first and second memory layer. The word line may comprise a conductive material that generates a third magnetic field when electrical current passes through the word line. The word line comprises at least one magnetic keeper that is configured to concentrate the third magnetic field generated by the word line towards at least one of the first programmable component and the second programmable component. [0012] Moreover, the first memory layer may comprise a plurality of first programmable components that are configured in a grid array having columns and rows. The second memory layer may comprise a plurality of second programmable components that are configured in a grid array having columns and rows. The memory device may also comprise a plurality of word lines that are formed between the first and second memory layers in a manner such that each of the word lines defines a column comprising at least one of the plurality of first programmable components and at least one of the plurality of second programmable components. The first programmable component and the second programmable component may be selected from the group consisting of a pseudo spin valve (PSV) device, magnetic tunneling junction (MTJ) device, an inline giant magneto-resistive (GMR) device, and a magneto-resistive random access memory (MRAM) device. [0013] The aforementioned needs may also be satisfied by a memory device comprising, in one embodiment, a substrate having a first surface, a first memory layer having a first plurality of memory components formed on the first surface of the substrate, wherein the first plurality of memory components are positioned in a first grid array having rows and columns, and wherein each of the first plurality of memory components can be configured to store a logic state therein by selective magnetization, and a second memory layer having a second plurality of memory components formed on the first memory layer in an overlying manner so as to increase the storage component density of the memory device, wherein the second plurality of memory components are positioned in a second grid array having rows and columns, and wherein each of the second plurality of memory components can be configured to store a logic state therein by selective magnetization. [0014] In one aspect, the memory device may further comprise a first plurality of electrodes that are formed in the first memory layer so as to be substantially parallel to the rows in the first grid array and electrically interconnected to the first plurality of programmable components and a second plurality of electrodes that are formed in the second memory layer so as to be substantially parallel to the rows in the second grid array and electrically interconnected to the second plurality of programmable components. The memory device may still further comprise a plurality of proximate word lines formed between the first and second memory layers so as to be substantially parallel to the columns of the first and second grid arrays and substantially perpendicular to the first and second plurality of electrodes. [0015] In another aspect, selective magnetization of at least one of the first plurality of memory components may occur when electrical current simultaneously passes through at least one of the first plurality of electrodes and through the corresponding proximate word line. In addition, selective magnetization of at least one of the second plurality of memory components may occur when electrical current simultaneously passes through at least one of the second plurality of electrodes and through the corresponding proximate word line. Also, each of the proximate word lines may generate a proximate magnetic field towards the first and second memory layer. Furthermore, each proximate word line may comprise at least one magnetic keeper that is configured to concentrate the generated magnetic field towards at least one of first memory layer and the second memory layer. [0016] The aforementioned needs may be further satisfied by a method of forming a magnetic memory device on a substrate. In one embodiment, the method may comprise forming a first and second electrode on the substrate, forming a first magnetic memory component on the first and second electrode in a manner so as to be electrically coupled therewith, forming a first insulation layer on the substrate in a manner so as to overlie the first magnetic memory component and the first and second electrode, and forming a word line on the first insulation layer. The method may further comprise forming a second insulating layer on the first insulating layer in a manner so as to overlie the word line, forming a third and fourth electrode on the second insulating layer, forming a second magnetic memory component on the third and fourth electrode in a manner so as to be electrically coupled therewith, wherein forming the second magnetic component increases the storage and fabrication density of the memory device, and forming a third insulating layer on the second insulating layer in a manner so as to overlie the second magnetic memory component and the third and fourth electrodes. [0017] The aforementioned needs may also be satisfied by another method of increasing the density of a magnetic memory device having a substrate. In another embodiment, the method may comprise forming a first memory layer on the substrate, wherein the first memory component comprises at least one magnetic storage component and a plurality of electrodes electrically coupled therewith, forming a word line on the first memory layer, and forming second memory layer above the word line, wherein the second memory layer comprises at least one magnetic storage component and a plurality of electrodes electrically coupled therewith, and wherein forming the second memory layer increases the fabrication density of the magnetic memory device. [0018] In one aspect, forming the first memory layer may include planarizing the first memory layer. In another aspect, the method may further comprise forming a first insulation layer between the first memory layer and the word line, wherein forming the word line includes planarizing the word line. In addition, the method may further comprise forming a second insulation layer between the word line and the second memory layer, wherein forming the second memory layer includes planarizing the second memory layer. Moreover, the method may still further comprise forming one or more additional memory layers on the second memory layer, wherein the one or more additional memory layers comprise at least one magnetic storage component and a plurality of electrodes electrically coupled therewith. Furthermore, the method may yet further comprise forming one or more insulation layers between the additional memory layers. These and other objects and advantages of the present teachings will become more fully apparent from the following description taken in conjunction with the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS [0019] FIGS. 1A-1L illustrate one embodiment of a method of forming a magneto-resistive memory element of a magnetic memory device having at least a double density structure. [0020] FIG. 1M illustrates one embodiment of a plurality of magnetic memory layers that may be stacked in a layered configuration so as to form a multiple layer grid array. [0021] FIG. 2A illustrates another embodiment of a magnetic memory device that may comprise a plurality of magnetic memory layers having at least one word line. [0022] FIG. 2B illustrates another embodiment of a plurality of magnetic memory layers that may be stacked in a layered configuration so as to form another multiple layer grid array. [0023] FIG. 3A illustrates still another embodiment of a magnetic memory device that may comprise a plurality of magnetic memory layers having at least one word line. [0024] FIG. 3B illustrates still another embodiment of a plurality of magnetic memory layers that may be stacked in a layered configuration so as to form a still another multiple layer grid array. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT [0025] The present teachings relate to structures and methods for forming magneto-resistive memory and associated electrode structures. FIGS. 1A-1L illustrate one embodiment of a method of forming a magneto-resistive memory element of a magnetic memory device having at least a double density structure. Reference will now be made to the drawings wherein like numerals refer to like parts throughout. [0026] FIG. 1A illustrates one embodiment of a substrate 100 having a substantially planar substrate surface 102 upon which a magnetic memory element, such as a magnetic memory device structure, will be fabricated in accordance with a method of the present teachings. The substrate 100 may comprise, for example, layers and structures (not shown) which are generally known in the art for the formation of electrical circuitry. [0027] As used herein, the term “substrate” or “semiconductor substrate” shall encompass structures comprising semiconductor material, including, but not limited to, bulk semiconductor materials such as a semiconductor wafer (either alone or in assemblies comprising other materials thereon), and semiconductive material layers (either alone or in assemblies comprising other materials). The term “substrate” or “semiconductor substrate” shall also encompass, for example, semiconductor-on-insulator (SOI) structures. In addition, the term “substrate” or “semiconductor substrate” shall further encompass any supporting structures, including, but not limited to, the semiconductive substrates described herein below. Furthermore, when reference is made to the term substrate within the following description, previous process steps may have been utilized to form regions, structures, or junctions in or on its base semiconductor structure or foundation. [0028] It should be appreciated that the scope of the present teachings may encompass substrates of non-flat surfaces or structures over which an insulating material may be deposited and then planarized using, for example, a generally known chemical mechanical planarization (CMP) process to form a substantially planar surface upon which fabrication of a magnetic memory element, as described herein, may be accomplished in accordance with a method of the present teachings. In addition, an epitaxial layer, comprising, in one embodiment, Silicon, may be formed on the substrate 100 adjacent the substrate surface 102 using, for example, a chemical vapor deposition (CVD) process. As is generally known in the art, an epitaxial Silicon layer typically comprises fewer impurities than a Silicon wafer. Therefore, the epitaxial Silicon layer comprises a higher grade of Silicon than the Silicon wafer due to the deposition of Silicon using the CVD process. [0029] FIG. 1B illustrates one embodiment of a first plurality of electrodes formed on the substrate 100 , wherein a first and second electrode 110 , 112 may be formed below the substrate surface 102 using, for example, a generally known dual damascene process. The first and second electrodes 110 , 112 may comprise a conductive material, such as copper (Cu), having a thickness of approximately 2000 Å. In one aspect, copper is a desirable conductor to use for metalization in integrated circuitry due to its low resistivity and high electromigration resistance. [0030] As is known in the art, the dual damascene process involves forming recessed cavities in a substrate, such as the substrate 100 . After depositing conductive material, such as copper, in the recessed cavities using known techniques, a CMP process is used to planarize the upper surface of the substrate so that the upper portion of the conductive material is substantially co-planar with the upper surface of the substrate 100 . It should be appreciated that the first electrode 110 may be used as a first electrical contact reference point for a first magnetic memory element. In addition, the second electrode 112 may be used as a second electrical contact reference point for the first magnetic memory element, which will be described in greater detail herein below. [0031] FIG. 1C illustrates one embodiment of a first magnetic memory structure 120 formed on the substrate 100 above the substrate surface 102 in a manner so to form a first magnetic memory layer 122 . The first magnetic memory structure 120 may also be referred to as a magnetic memory bit, wherein a logic state may be stored in the magnetic memory bit or structure 120 in a manner that will be described in greater detail herein below. The first magnetic memory structure 120 may comprise, for example, an magneto-resistive random access memory (MRAM) cell, an inline giant magneto-resistive (GMR) cell, a pseudo-spin valve (PSV) cell, a magnetic tunneling junction (MTJ) cell, or various other generally known embodiments of magnetic memory cells. As illustrated in FIG. 1C , the first magnetic memory layer 122 includes the first magnetic memory structure 120 and the corresponding first and second electrodes 110 , 112 . [0032] In one aspect, a conventional magnetic memory structure may comprise layers of magnetic material including at least a hard magnetic layer, an inner layer, a soft magnetic layer, and one or more contact electrodes. It should be appreciated that various practical applications of the magnetic memory structure 120 may further comprise various other layers for specialized functions without departing from the scope of the present teachings. It should also be appreciated that the overall thickness of the magnetic memory structure 120 may vary depending on the particular application and device configuration used. Therefore, changes and/or alterations to the disclosed embodiment may be made by one skilled in the art without departing from the scope of the present teachings. [0033] The hard magnetic layer may comprise, in one embodiment, a “hard” magnetic material, such as a layer of NiFe, NiFeCo, or CoFe, with a first thickness between about 10 Å and 50 Å. The “hard” magnetic material is so called due to its magnetization orientation is maintained in the face of relatively low magnetic fields used during operation. Magnetic memory stack layers, including the hard magnetic layer, may be formed in a manner generally known in the art by deposition techniques, such as sputter-deposition, physical vapor deposition, or ion-beam deposition. After deposition of the “hard” magnetic material, the hard magnetic layer may be planarized using a CMP process so as to provide a substantially flat, smooth upper surface for the deposition of additional overlying layers. In one aspect, the hard layer may be magnetized in a first fixed direction and acts as a first reference point for the net directional magnetization vectors of the magnetic memory structure 120 . Accordingly, the hard magnetic layer may also be referred to herein as the magnetically pinned layer. [0034] The soft magnetic layer may comprise, in one embodiment, a “soft” magnetic material, such as a layer of NiFe, NiFeCo, or CoFe, with a second thickness of approximately 30 Å and may be positioned above or below the hard magnetic layer. The “soft” magnetic material is so-called due to its readily re-oriented magnetization by relatively weak magnetic fields, and so serves as the “sense” layer in the magnetic memory structure 120 . Magnetic memory stack layers, including the soft layer, are formed in a manner generally known in the art by deposition techniques, such as sputter-deposition, physical vapor deposition, and ion-beam deposition. After deposition of the “soft” magnetic material, the soft magnetic layer may be planarized using a CMP process so as to provide a substantially flat, smooth upper surface for the deposition of additional overlying layers. In one aspect, the soft or sense layer may be magnetized in the first fixed direction or a second direction opposite of the first direction, depending on an applied magnetic field, and provides a second reference point for the net directional magnetization vectors of the magnetic memory structure 120 . Accordingly, the soft magnetic layer may also be referred to herein as the magnetically programmable layer. [0035] In one embodiment, PSV cells use an inner layer that may comprise a thin layer of copper (Cu) that is approximately 10 to 30 Å thick and positioned interposedly between the hard and soft magnetic layers. Various fabrication techniques utilized for forming the inner layer may include depositing a copper material in a manner generally known in the art using deposition techniques, such as chemical vapor deposition (CVD) and plasma enhanced CVD (PECVD), wherein all may be derived in a manner generally known in the art. After deposition of the dielectric material, the inner layer may be planarized using a CMP process so as to provide a substantially flat, smooth upper surface for the deposition of additional overlying layers. In one aspect, the inner layer serves as a conduit for current to flow through the magnetic memory structure 120 . In one aspect, the above-mentioned PSV stacked layers of the magnetic memory structure 120 may be oriented and/or positioned to comprise a current-in-plane (CIP) configuration, wherein the read and/or write current passes in a substantially parallel manner through the structure 120 . [0036] In an alternative embodiment, MTJ cells use an inner layer that may comprise a thin dielectric layer of Aluminum Oxide (Al 2 O 3 ) that is approximately 10 to 15 Å thick and positioned interposedly between the hard and soft magnetic layers. Various fabrication techniques utilized for forming the inner layer may include depositing an aluminum layer in a manner generally known in the art, and, then, oxidation of the aluminum layer may achieved by one of several different methods, such as plasma oxidation, oxidation by air, and ion-beam oxidation, wherein all may be derived in a manner generally known in the art. After deposition of the dielectric material, the inner layer may be planarized using a CMP process so as to provide a substantially flat, smooth upper surface for the deposition of additional overlying layers. In one aspect, the thin dielectric layer serves as a tunneling conduit for excited electrons to flow through without causing dielectric breakdown of the magnetic memory structure 120 at low voltages. Accordingly, the inner layer may also be referred to herein as the tunneling dielectric layer. In one aspect, the above-mentioned TMJ stacked layers of the magnetic memory structure 120 may be oriented and/or positioned to comprise a current-perpendicular-to-plane (CPP) configuration, wherein the read and/or write current passes in a substantially perpendicular manner through the structure 120 . [0037] In a manner as described above, magnetic memory cells, devices, and/or structures may comprise vertically ordered layers of material that exhibit a variable resistance depending on the magnetization state of the material. Some magnetic memory cells, devices, and/or structures incorporate at least two layers of magnetic material separated by at least one layer of dielectric material. As previously described, the magnetic layers may comprise a hard (magnetically pinned) layer and a soft (magnetically programmable) layer. The selective programmability of the soft layer enables the magnetic memory cells, devices, and/or structures to function as a logic state device, which may be used to store binary data as directions of net magnetization vectors in at least one of the magnetic layers. In one aspect, current flow through two proximate orthogonal conductors may be used to polarize the magnetic components of the soft layer in either a parallel or antiparallel direction. [0038] Therefore, the parallel and antiparallel magnetization states of the magnetic layers may correspond to at least two different resistance states, wherein a high and low resistance state may represent a logical “1” or “0,” respectively. In other words, when the magnetic materials are layered in a particular fashion, they may exhibit a variable vertical electrical resistance depending on the magnetization state of the individual layers. For example, if the magnetic layers are individually magnetized in the same (parallel) direction, the magnetic memory cells, devices, and/or structures exhibit a low electrical resistance. Whereas, if the magnetic layers are individually magnetized in opposite (antiparallel) direction, the magnetic cells, devices, and/or structures exhibit a high electrical resistance. In one aspect, when the magnetic components of the layers are aligned in parallel, the current may travel through the magnetic material with minimal scattering, which may result in an overall lower resistance. However, in the case where magnetic layers are oppositely magnetized, the current may flow with increased scattering due to the antiparallel orientation of the magnetic components. [0039] As described above, the first magnetic memory structure 120 represents one of many useable configurations of a magnetic memory cell structure in a stacked formation. In one embodiment, there are essentially two conducting layers that are separated by a thin dielectric layer. In other arrangements, the skilled artisan will appreciate that the order of the layers may be altered, such that the magnetically programmable layer is positioned above or below the magnetically fixed layer, while maintaining the interposed position of the tunneling dielectric layer. It should be appreciated that practical applications of the proposed magnetic memory cell structure may include other layers for specialized functions without departing from the scope of the present teachings. [0040] FIG. 1D illustrates one embodiment of a first insulating layer 126 formed on the first magnetic memory layer 122 in a manner so as to overlie the magnetic memory structure 120 and the corresponding electrodes 110 , 112 . The first insulating layer 126 may comprise an insulating material, such as silicon-dioxide (SiO 2 ), having a thickness of approximately 4000 Å. After deposition of the insulating material, the first insulating layer 126 may be planarized using a CMP process so as to provide a substantially flat, smooth upper surface for the deposition of additional overlying layers. As illustrated in FIG. 1D , the first insulating layer 126 serves as an insulating and spacing barrier between a plurality of stacked magnetic memory layers in a manner as will be described in greater detail herein below. [0041] FIGS. 1E-1H illustrate the formation of one embodiment of a word line 130 having a first and second keeper 132 , 134 that may be formed adjacent to the upper surface of the first insulating layer 126 . It should be appreciated that the keepers 132 , 134 may also be referred to as magnetic keepers without departing from the scope of the present teachings. [0042] FIG. 1E illustrates one embodiment of a first recessed well 124 formed in the first insulating layer 126 . The first recessed well 124 , having a depth of approximately 2000 Å and a width of approximately 4300 Å, may be formed adjacent to the upper surface of the first insulating layer 126 and above the magnetic memory structure 120 using a generally known pattern and etch technique. In a preferred embodiment, the etching technique may comprise a generally known anisotropic etching technique so as to form substantially vertical walls in the first recessed well 124 in a manner as illustrated in FIG. 1E . [0043] FIG. 1F illustrates one embodiment of a keeper layer 127 formed in the first recessed well 124 of FIG. 1E in a manner so as to fill the first recessed well 124 adjacent the upper surface of the first insulating layer 126 . The keeper layer 127 may be deposited using generally known deposition techniques, such as such as sputter-deposition, physical vapor deposition, and ion-beam deposition and then planarized to the upper surface of the first insulating layer 126 using a generally known CMP process. In one aspect, the keeper layer 127 may be uniformly deposited so as to overlie the first insulating layer 126 including the first recessed well 124 . In addition, the keeper layer 127 may comprise a magnetic material, such as Ni 80 Fe 20 , having a thickness of approximately 400 Å. [0044] FIG. 1G illustrates the formation of first and second magnetic keepers 132 , 134 at each distal end of the keeper layer 127 by forming a second recessed well 128 in the keeper layer 127 . The second recessed well 128 , having a depth of approximately 2000 Å and a width of approximately 3500 Å, may be formed in the same manner as described with reference to the formation of the first recessed well 124 in FIG. 1E . In one embodiment, the first and second magnetic keepers 132 , 134 may comprise a thickness or height 136 of approximately 2000 Å and a width 138 of approximately 400 Å. The scope and functionality of the magnetic keepers 132 , 134 will be described in greater detail herein below with reference to FIG. 1H . [0045] FIG. 1H illustrates one embodiment of a word line 130 formed in the second recessed well 128 and adjacent to the upper surface of the first insulating layer 126 . As illustrated in FIG. 1H , the word line 130 is further formed in a manner so as to be interposed between the first and second magnetic keepers 132 , 134 . In one aspect, the word line 130 may be formed below the upper surface of the first insulating layer 126 using, for example at least in part, a generally known dual damascene process. The process of forming the word line 130 is similar to above-described process of forming the first and second electrodes 110 , 112 in FIG. 1B . The word line 130 may comprise a conductive material, such as copper, having a thickness of approximately 2000 Å. In one aspect, the word line 130 comprises a proximate conductor that serves as a magnetic field generator for the purpose of programming the net magnetization vectors of the magnetic memory structure 120 , wherein the word line 130 may be positioned substantially perpendicular to the electrodes 110 , 112 . As is known in the art, the net magnetization vectors of the magnetic memory structure 120 may be altered and/or changed by current flowing in a proximate conductor. [0046] In one embodiment, the first and second keepers and/or magnetic keepers 132 , 134 may be utilized as magnetic field or flux concentrators, which may be configured to influence the direction of the magnetic field from the word line 130 in an upward and/or downward direction relative to the word line 130 . In one aspect, a “soft” magnetic material may be deposited on the sides of the word line 130 to serve as magnetic keeper layers, which may assist with concentrating the magnetic field generated by current flowing through the conductive word line 130 away from the sides of the word line 130 and towards the upper and lower regions of the word line 130 . In a manner as previously described, the first and second magnetic keepers 132 , 134 may be positioned adjacent the word line 130 as illustrated in FIG. 1H . For further description relating to the scope and functionality of magnetic keepers, the Applicant's co-pending patent application entitled “A Method for Building a Magnetic Keeper or Flux Concentrator Used for Writing Magnetic Bits” (Ser. No. 10/226,623 now U.S. Pat. No. 6,914,805) is hereby incorporated by reference in its entirety. [0047] FIG. 1I illustrates one embodiment of a second insulating layer 140 formed on the upper surface of the first insulating layer 126 in a manner so as to overlie the first insulating layer 126 and the word line 130 including the magnetic keepers 132 , 134 . Similar to the first insulating layer 126 , the second insulating layer 140 may comprise an insulating material, such as silicon-dioxide (SiO 2 ), having a thickness of approximately 4000 Å. After deposition of the insulating material, the second insulating layer 140 may be planarized using a CMP process so as to provide a substantially flat, smooth upper surface for the deposition of additional overlying layers. As illustrated in FIG. 1I , the second insulating layer 140 serves as an additional insulating and spacing barrier between stacked magnetic memory layers in a manner as will be described in greater detail herein below. [0048] FIG. 1J illustrates one embodiment of a second plurality of electrodes formed on the second insulating layer 140 , wherein a third and fourth electrode 150 , 152 may be formed below the upper surface of the second insulating layer 140 using, for example, a generally known dual damascene process. Similar to the first and second electrodes 110 , 112 , the third and fourth electrodes 150 , 152 may comprise a conductive material, such as copper, having a thickness of approximately 2000 Å. As previously described, copper is a desirable conductor to utilize and implement for metalization in integrated circuitry due to its low resistivity and high electromigration resistance. [0049] As previously described with reference to FIG. 1B , the dual damascene process involves forming recessed cavities in a substrate material, such as the second insulating layer 140 . After depositing conductive material, such as copper, in the recessed cavities using known techniques, a CMP process is used to planarize the upper surface of the substrate such that the upper portion of the conductive material is substantially co-planar with the upper surface of the second insulating layer 140 . It should be appreciated that the third electrode 150 may be used as a first electrical contact reference point for a second magnetic memory element. In addition, the fourth electrode 152 may be used as a second electrical contact reference point for the second magnetic memory element, which will be described in greater detail herein below. [0050] FIG. 1K illustrates one embodiment of a second magnetic memory structure 160 formed on the upper surface of the second insulating layer 140 in a manner so to form a second magnetic memory layer 162 . Similar to the first magnetic memory structure 120 , the second magnetic memory structure 160 may comprise, for example, an MRAM cell, magnetic tunneling junction (MTJ) cell, a pseudo-spin valve cell, or various other generally known embodiments of magnetic memory cells. As illustrated in FIG. 1K , the second magnetic memory layer 162 includes the second magnetic memory structure 120 and the corresponding third and fourth electrodes 150 , 152 . [0051] In one aspect, the second magnetic memory structure 160 may comprise similar scope, composition, and functionality as with the first magnetic memory structure 120 . Additionally, each layer of the second magnetic memory structure 160 may be planarized using a CMP process so as to provide a substantially flat, smooth upper surface for the deposition of other overlying layers. In one embodiment of the present teachings, the formation of the first and second magnetic memory layers 122 , 162 , including the first and second magnetic memory structures 120 , 160 and the first, second, third, and fourth electrodes 110 , 112 , 150 , 152 , would involve the same processing steps. It should be appreciated that, depending on the particular application of the device, the first and second magnetic memory structures 120 , 160 may comprise different cell configurations without departing from the scope of the present teachings. [0052] As previously described above, the second magnetic memory structure 160 represents one of many useable configurations of a magnetic memory cell structure in a stacked formation. In one embodiment, there are essentially two conducting layers that are separated by a thin dielectric layer. In other arrangements, the skilled artisan should appreciate that the sequential order of layers may be altered and/or changed, such that the “soft” layer is positioned above or below the “hard” layer, while maintaining the interposed position of the inner layer. It should be appreciated that most practical applications of the above-mentioned magnetic memory cell structure may include various layers comprising specialized functions without departing from the scope or spirit of the present teachings. [0053] FIG. 1L illustrates one embodiment of a third insulating layer 156 formed on the upper surface 142 of the second insulating layer 140 in a manner so as to overlie the second insulating layer 140 and the second magnetic memory layer 162 . The third insulating layer 156 may comprise an insulating material, such as silicon-dioxide (SiO 2 ), having a thickness of approximately ≧5000 Å. After deposition of the insulating material, the third insulating layer 156 may be planarized using a CMP process so as to provide a substantially flat, smooth upper surface for the deposition of, for example, additional overlying layers. As illustrated in FIG. 1L , the third insulating layer 156 serves as an insulating barrier between second magnetic memory layer 162 in a manner so as to provide insulation from the environment and/or other integrated circuit components. Due to the physical arrangements of the above-mentioned layers, magnetic memory structures may follow the same high-density fabrication techniques as their semiconductor counterpart. [0054] FIG. 1L further illustrates one embodiment of a magnetic memory device 180 having at least two magnetic memory layers 122 , 162 and at least one word line 130 that may be formed by the above-mentioned fabrication process as referenced by FIGS. 1A-1L . It should be appreciated that one or more word lines 130 may be used in the first magnetic memory device 180 to program the magnetic memory structures 120 , 160 by one skilled in the art without departing from the scope of the present teachings. [0055] As further illustrated in FIG. 1L , the at least two magnetic memory layers 122 , 162 and at least one word line 130 may be formed and positioned in a column configuration, wherein the at least one word line 130 may be used to influence and/or program the magnetically programmable logic state of one or more of the at least two magnetic memory layers 122 , 162 . It should be appreciated that the at least two magnetic memory layers 122 , 162 and the at least one word line 130 may be formed and positioned in a row configuration without departing from the scope of the present teachings. [0056] In one aspect, a plurality of magnetic memory structures or bits may be positioned adjacent to each other and interconnected in a manner so as to form a grid array within a single magnetic memory layer. As illustrated in FIG. 1M , a plurality of magnetic memory layers may be stacked so as to form one embodiment of a multiple layer grid array 190 , wherein the first magnetic memory layer 122 may comprise a first plurality of magnetic memory structures or bits configured in a first grid array, and the second magnetic memory layer 162 may comprise a second plurality of magnetic memory structures or bits in a second grid array. As further illustrated in FIG. 1M , a plurality of word lines 130 may be interposedly positioned between the first and second memory layers 122 , 162 so as to form a column of magnetic memory structures or bits. [0057] Advantageously, the illustrated double density configuration 190 of the magnetic memory device 180 comprises increased storage capacity and preferably uses one word line 130 to write to a column of magnetic memory bits 120 , 160 . It should be appreciated that additional magnetic memory layers may be formed above and below the first and second magnetic memory layers 122 , 162 in a manner as previously described with reference to FIGS. 1A-1L , wherein the magnetic memory device 180 , which may include devices such as MRAM, may comprise one or more stacked magnetic memory cells, structures, and/or layers to improve component density. [0058] It should also be appreciated that the current flowing in the word line 130 and the distance between structures 120 , 130 , 160 may be selected so that the generated magnetic field by the first word line 130 affects or influences the magnetization state of the first and second magnetic memory structure 120 , 160 in a manner that is substantially similar. Preferably, the generated magnetic field by the word line 130 affects and influences the first magnetic memory structure 120 when a current is present in the first and second electrodes 110 , 112 . Additionally, the generated magnetic field by the word line 130 affects and influences the second magnetic memory structure 160 when a current is present in the third and fourth electrodes 150 , 152 . In one aspect, the magnetic field generated in the first and second electrodes 110 , 112 does not interfere with the magnetic field generated by the current in the third and fourth electrodes 150 , 152 . [0059] FIG. 2A illustrates another embodiment of magnetic memory device 280 further comprising a plurality of magnetic memory layers 122 , 162 , 222 having at least one word line 130 . As illustrated in FIG. 2A , the magnetic memory device 280 may comprise the same scope and functionality of the magnetic memory device 180 as illustrated in FIGS. 1A-1L with the addition of a third magnetic memory layer 222 . It should be appreciated that additional magnetic memory layers may be formed above and/or below the first and second magnetic memory layers 122 , 162 in a manner as previously described by one skilled in the art without departing from the scope of the present teachings. In addition, it should also be appreciated that the order in which the magnetic memory layers 122 , 162 , 222 , including the at least one word line 130 , are positionally oriented and/or configured may be changed and/or altered by one skilled in the art without departing from the scope of the present teachings. [0060] In one embodiment, a fourth insulating layer 200 may be formed on the upper surface of the third insulating layer 156 in a manner so as to overlie the third insulating layer 156 and provide a surface 202 for forming the additional (third) magnetic memory layer 222 . In one aspect, the third magnetic memory layer 222 may comprise a third plurality of electrodes formed on the third insulating layer 156 , wherein a fifth and sixth electrode 210 , 212 may be formed below the upper surface of the third insulating layer 156 using, for example, a generally known dual damascene process. In addition, the third magnetic memory layer 222 may further comprise a third magnetic memory structure 220 , which may be formed in a similar manner as with the first and second magnetic memory structures 120 , 160 . After forming the third magnetic memory layer 222 , a fifth insulating layer 216 may be formed on the upper surface of the fourth insulating layer 200 in a manner so as to overlie the fourth insulating layer 200 and the third magnetic memory layer 222 in a manner as previously described with reference to the third insulating layer 156 in FIG. 1L . [0061] Advantageously, as illustrated in FIG. 2A , a plurality of magnetic memory layers 122 , 162 , 222 may be configured in a column orientation to comprise a plurality of magnetic memory structures or bits 120 , 160 , 220 that may be programmed using a single word line 130 . The current through the word line 130 may be adjusted to influence the one or more magnetic memory bits 120 , 160 , 220 . By layering magnetic memory bits 120 , 160 , 220 above the substrate 100 in a column orientation, an increase in areal device density of magnetic memory may be achieved without increasing the substrate surface requirement for increased device density. Therefore, in one aspect, the areal density of the magnetic memory bits within the substrate plane is no longer bounded by at least the amount of planar space available on the upper surface of the substrate. Additionally, by using a single word line 130 to influence the programmable magnetization of a plurality of magnetic memory bits 121 , 160 , 210 , an increase in device efficiency may also be achieved. As a result, an increase in magnetic memory device performance, reliability, and functionality is achieved. [0062] Additionally, as illustrated in FIG. 2B , a plurality of magnetic memory structures or bits may be positioned adjacent to each other and interconnected in a manner so as to form another embodiment of a multiple layer grid array 290 using the plurality of magnetic memory layers 122 , 162 , 222 . In one aspect, the first magnetic memory layer 122 may comprise the first plurality of magnetic memory structures or bits configured in the first grid array, the second magnetic memory layer 162 may comprise the second plurality of magnetic memory structures or bits in the second grid array, and a third magnetic memory layer 222 may comprise a third plurality of magnetic memory structures or bits in a third grid array. As further illustrated in FIG. 2B , a plurality of word lines 130 may be interposedly positioned between the first, second, and third memory layers 122 , 162 , 222 so as to form a plurality of columns each having a plurality of magnetic memory structures or bits. [0063] Advantageously, the illustrated triple density configuration 290 of the magnetic memory device 280 of FIG. 2A may comprise increased storage capacity and preferably uses a single column positioned word line 130 to write to a single column of magnetic memory bits 120 , 160 , 222 . It should be appreciated that one or more additional magnetic memory layers may be formed above and/or below the first, second, and third magnetic memory layers 122 , 162 , 222 in a manner as previously described, wherein the first magnetic memory device 180 , which may include devices such as MRAM, may comprise one or more stacked magnetic memory cells, structures, layers, and/or grid arrays to improve component density without departing from the scope of the present teachings. [0064] FIG. 3A illustrates still another embodiment of a magnetic memory device 300 that may comprise a plurality of magnetic memory layers 122 , 362 having at least one word line 130 . In one aspect, the third magnetic memory device 300 may comprise the same scope and functionality of the first magnetic memory device 180 as illustrated in FIGS. 1A-1L with the formation of first and fourth electrodes above the upper surface 142 of the second insulating layer 140 . It should be appreciated that the electrodes 150 , 152 may be formed using a generally known pattern and etch metallization technique, such as chemical vapor deposition (CVD). In addition, the electrodes 150 , 152 may be positionally oriented in a manner so as to electrically interconnect with the second magnetic memory structure 160 and form a fourth magnetic memory layer 362 . [0065] FIG. 3B illustrates yet another embodiment of a magnetic memory device 320 that may comprise a plurality of magnetic memory layers 122 , 362 , 392 having at least one word line 130 . As illustrated in FIG. 3B , the magnetic memory device 320 may comprise the same scope and functionality of the magnetic memory device 300 as illustrated in FIG. 3A with the addition of another (fifth) magnetic memory layer 392 . It should be appreciated that additional magnetic memory layers may be formed above or below the first and fourth magnetic memory layers 122 , 162 in a manner as previously described by one skilled in the art without departing from the scope of the present teachings. In addition, it should also be appreciated that the order in which the magnetic memory layers 122 , 362 , 392 , including the at least one word line 130 , are positionally oriented and/or configured may be changed and/or altered by one skilled in the art without departing from the scope of the present teachings. [0066] In one embodiment, a fifth magnetic memory structure 390 and a plurality of electrodes 380 , 382 may be formed on the upper surface of the third insulating layer 156 in a manner as previously described with reference to the fourth magnetic memory layer 362 in FIG. 3A . In addition, after forming the fifth magnetic memory layer 392 , a sixth insulating layer 386 may be formed on the upper surface of the third insulating layer 156 in a manner so as to overlie the third insulating layer 156 and the fifth magnetic memory layer 392 . [0067] Although the following description exemplifies one embodiment of the present teachings, it should be understood that various omissions, substitutions, and changes in the form of the detail of the apparatus, system, and/or method as illustrated as well as the uses thereof, may be made by those skilled in the art, without departing from the scope of the present teachings. Consequently, the scope of the present teachings should not be limited to the disclosed embodiments, but should be defined by the appended claims.

The semiconductor industry seeks to replace traditional volatile memory devices with improved non-volatile memory devices. The increased demand for a significantly advanced, efficient, and non-volatile data retention technique has driven the development of integrated magnetic memory structures. In one aspect, the present teachings relate to magnetic memory structure fabrication techniques in a high density configuration that includes an efficient means for programming high density magnetic memory structures.

RELATED APPLICATIONS [0001] This application claims priority from U.S. Provisional Patent Application No. 60/177,848 filed on Jan. 25, 2000. The entire disclosure of the provisional application is considered to be part of the disclosure of the accompanying application and is hereby incorporated by reference. FIELD OF THE INVENTION [0002] The present invention is directed to an educational trading card game and method, and in particular, is directed to trading cards depicting important historical figures, events and locations which serve to teach students the historical significance of such people and events in world history. BACKGROUND OF THE INVENTION [0003] The trading of various different types of cards has stirred the imagination of children and young adults throughout the decades. Recently, the Pokémon trading card game has generated much interest, as well as concern. The game of Pokémon was created in Japan and became widely popular in the United States in 1998. There are presently over 150 different kinds of Pokémon, with each different Pokémon having different powers and abilities. One goal of the Pokémon trading card game is to capture and train wild Pokémon so that such Pokémon do battle with other Pokémon. Competitors in the Pokémon trading card game play a card game much like other card games wherein each has a deck of cards, cards are drawn and held in one's hand and the cards are played when the player's turn comes around. Pokémon trading cards are different in certain respects, however, given that the cards with Pokémon on them are similar to game pieces in chess or checkers in that once a person has played such cards from their hand, such cards stay on the table and continue to effect the game's outcome. Another difference between a regular card game and a trading card game like Pokémon is that every player makes his or her own personalized deck of cards. A part of the enjoyment of such game is the making of different decks that reflect different themes and enable the player to try out different game strategies. [0004] Pokémon cards are often traded between children to complete collections of such cards or to obtain cards that are perceived as needed for their personal card decks. Certain cards are produced in limited numbers and are therefore rare. For example, there is a limited number of holographic foil cards produced, and such rarity commands a higher price for such cards when traded. Thus, not all Pokémon cards are as easy to obtain as others, with some cards being common and other cards being more rare, indicated by different geometrical shaped icons on the face of each card. Each Pokémon has its own special fighting abilities. Although Pokémons come in many shapes and sizes, even the smallest Pokémon is capable of launching a fierce attack. Some Pokémon grow or evolve into more powerful creatures. One goal of Pokémon is to collect each of the available cards. [0005] In Pokémon, there are three different ways of winning. Typically, at the start of the game, the players set aside six of their cards as prizes and every time one of an opponent's Pokémon is knocked out, a player is able to take one of such prizes. When all six prizes have been taken, the game is won. Another way of winning is if an opponent has no Pokémon left to fight against a player's Pokémon. Finally, a third way to win is if an opponent's deck is out of cards at the start of his or her turn. [0006] In Pokémon, there are four basic types of cards including the basic Pokémon, evolution cards, which make a particular Pokémon bigger and more powerful, energy cards, which provide particular Pokémon cards with energy needed to use in attacking the opponent, and finally, trainer cards, which are one shot cards that do something once and are then discarded. [0007] Along with the phenomenon of Pokémon, there has been significant public criticism of how the Pokémon trading card game has affected children. Complaints include that Pokémon encourages children to gamble due to the prize card rules. Reports indicate that some children are spending up to $100.00 just to buy certain ultra-rare Pokémon cards. Others argue that Pokémon cards do not appear to have any long-term value. Indeed, many school districts have banned Pokémon trading cards due to the negative effects experienced in the education of children preoccupied with the Pokémon trading card game. [0008] There is therefore a long-felt, but unsolved need for an educational tool which children and young adults can use to learn fundamental subjects, including history, science, geography, etc. in a fun and entertaining context. SUMMARY OF THE INVENTION [0009] The present invention is directed to a trading card game and method which is designed not only to be fun and entertaining for children and young adults, but is also educational in nature. Although various educational fields can be encompassed by the general concept of the present invention, for explanation and illustrative purposes the following discussion will emphasize one particular field, history, as a representative example of how the trading card game is played and the various identifying characteristics of the devices and methods employed. Thus, in one embodiment, an historical trading card game, hereinafter referred to as “Historicon” involves the use of a plurality of cards having graphic or photo illustrations of various historical figures and/or scenes reflecting important individuals and events having a significant impact on the history of man. The cards serve as a learning tool to teach children and young adults the hallmarks or keywords of such historical figures and events, enabling players (or as otherwise referred to herein as students or participants) to debate the significance of particular individuals and events in a historical context. [0010] One aspect of the invention is admittedly to replicate in many respects the popular Pokémon trading game with the important distinction that, unlike the Pokémon trading game, the present invention is directed to an educational tool. The present inventor has found that children playing the trading card game of the present invention, especially those previously exposed to the Pokémon trading card game, are adept at playing the trading card game invention and not only enjoy the game playing process, but also learn considerable amounts and retain such information to a far greater extent than as compared to traditional wrote book learning experiences. Indeed, one advantage of the present invention is that students, with little or no prompting from teachers and parents, play the trading card game of the present invention to such an extent that historical characters and events are learned almost effortlessly. Out-of-school dialog between students concerning interesting historical events and individuals opens up an entirely novel educational approach well suited for post X-generation individuals who have so many opportunities that divert them from educational tasks. [0011] In one embodiment of the present invention, historical card figures are separated into a plurality of categories such as leaders (kings, queens, emperors, presidents, etc); explorers (Columbus, Magellan, Lief Erickson, etc.), cultural contributors (authors, artists, musicians, philosophers, etc.); warriors (warlords, conquerors, generals, etc.); inventors (Alexander Graham-Bell, Thomas Edison, etc.); and scientists (Einstein, Heisenberg, Bohr, Galileo). It will be understood by those of skill in the art that various other categories can also be presented and used without departing from the scope and spirit of the present invention. [0012] As will be appreciated, some historical figures left their mark in more than one of the above referenced areas and thus may appear on more than one card. For example, Leonardo Da Vinci was well known an artist, inventor and scientist. Historical figures may also be portrayed in different periods of their life and so may appear on more than one card. For example, George Washington was a prominent figure in the French Indian War, the American Revolution and as a the first President of the United States. [0013] With respect to the plurality of possible layouts for trading cards of the present invention, the discussion below is again illustrative only of one particular embodiment and one of skill in the art will therefore appreciate and understand, with the guidance provided herein, that other formats can be adopted having equally effective results. In one embodiment of the present invention, the top of every card has a character's name as well as an “historical impact” (“HI”) score printed thereon. The HI score is based on criteria and determined out of total possible score (i.e. historical impact score of Christopher Columbus of 65 out of a possible 250). Below the name of the historical figure is presented a picture or other illustration of such figure. Other information is also provided below such picture describing either the type of historical and/or geographic region from which the historical figure derives from or had an impact on. Further information is supplied on the card including a listing of key words or hallmarks which the character is known for in history. For example, a Christopher Columbus card may have a listing of key words such as “Santa Maria”, “Admiral of the Seas” and “New World”. These key words may also correspond to with additional cards, for example “Civilization Connection” or “Energy” cards. Civilization connection or energy cards are chosen to have a particular numerical impact score, for example 100 of 250. Apart from individuals, particular events, especially particularly significant historical events, are termed “Wonders” and are given a higher score, i.e., 125-150 out of 250. [0014] On the face of the trading cards of the present invention, a symbol or dot is placed corresponding with the type of energy card used. Moreover, also included on the card is one or more trivial facts and a numerical sequence number, for example “1:25”. [0015] The trading cards of the present invention may be printed in various card colors to further heighten a child or young adults attention and to make the game more interesting. Background colors of the cards, however, are preferably selected to correspond to the type and nature of a particular card. For example, red may be used for ruler/leaders; white may be used for explorers; gray may be used warriors, etc. [0016] Another category of trading cards of the present invention are termed “Civilization Connection cards” and or “Energy cards”. Such cards connect a particular historical figure depicted on yet another set of cards with particular events, artifacts, trends, etc. during an historical period. For example, the American Civil War may be a key word for a leader such as Lincoln, warriors such as General Lee, Sherman and Grant, etc. Moreover, such civilization connection cards may be directed to specific historical events such as the Gettysburg Address or the Emancipation Proclamation. Such cards are similar in nature to the above-referenced figure cards, for example, “leader energy”, “explorer energy”, “culture energy”, “warrior energy”, etc. Additional energy cards can be provided for trade, economy, scientific discovery, etc. [0017] It is also within the scope of the present invention to have educational trading cards that correspond to a hallmark or key words found on particular individual's cards, thus providing a way to teach concepts not necessarily associated directly with particular historical figures. For example, animal domestication, hieroglyphic writing, the French-Indian Wards, Pythagorean Theorem, DNA, etc. are directed to concepts deemed important in human history. Indeed, such conceptual breakthroughs in history may also form the subject matter of an additional category of cards. [0018] In one embodiment, as with the Pokémon trading card game, it adopts in terms of rules, game playing strategies, etc. Particular cards may carry a more historical way and/or have more impact that others. Moreover, the cards may have an evolutionary type of component to this which is similar to concepts provided in the Pokémon trading card game. [0019] Another category of cards encompassed within the present invention are so-called “Wonder cards” which are special energy cards which describe wonders of the world at various time periods (for example, ancient times, the middle ages, the Renaissance and modern times) having particular historical significance. For example, the ancient wonders of the world can be compared with other later wonders created by man throughout history such as the Great Wall, Taj Majal, the Golden Gate Bridge, etc. These Wonder cards are designed to have more historical impact than others during the playing of the card game. [0020] The present inventors incorporate by reference the well known Pokémon trade card game and rules associated therewith. Such rules can be found, for example, on the Internet at “http://www.wizards.com/Pokémon/Rules”. The entirety of the Pokémon trading card game and rules associated therewith, card playing strategies, league play, collection strategies, etc., are therefore incorporated herein by this reference. Also incorporated herein in their entireties by this reference are trading card games encompassed by various U.S. patents, for example, U.S. Pat. No. 5,662,332 entitled “Trading Card Game and Method of Play”; U.S. Pat. No. 5,201,525 entitled “Card Game Utilizing Baseball Trading Cards”; U.S. Pat. No. 5,356,293 entitled “Sexually-Transmitted Disease Awareness Program Package”; U.S. Pat. No. 5,741,137 entitled “Educational Cards Teaching Emotional Expressions”. The above-referenced U.S. patents describe various methods of playing a trading card game and such general principles are incorporated herein by reference as being useful in structuring various different types of trading card games predicated upon the educational emphasis of the present invention as further described herein. BRIEF DESCRIPTION OF THE DRAWINGS [0021] [0021]FIG. 1 is a representative example of an Historicon card of the present invention illustrating Christopher Columbus as an important historical figure; [0022] [0022]FIG. 2 is a representative example of another trading card of the present invention indicating a so-called “energy” card depicting caravel vessels in a “war and defense” category. [0023] [0023]FIG. 3 is a representation of the two sides of an Historicon card with various components and positions of the same depicted. [0024] [0024]FIG. 4 illustrates an Historicon scenario card with various components depicted thereon. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT [0025] As discussed in the Summary of the Invention, the present invention is directed to an educational trading card game similar in many respect to the Pokémon trade card game. Indeed, Applicants incorporate by reference the format, information and trading card game strategies and procedures and rules involved in the Pokémon game in playing the Historicon game of the present invention. As will be understood by those of skill in the art, although the present invention has been described by reference to historical trading cards, similar types of educational trading cards can be provided for various areas such as: science (e.g. explaining principles, concepts, figures, theories, (evolution, physics, chemistry, biology) etc. through graphic illustrations and numerical and word-based educational representations); Mathematical Fields (e.g. theorems, proofs, Euclidean geometry, trigonometry, calculus, etc.) Politics; Art; Architecture; Business; Law; Medicine; Literature and Philosophy. As one will appreciate, the various colors, particular wording, particular numerical weighing of importance, etc. can be varied without departing from the scope and intent of the present invention. [0026] It will be further understood that although the present invention has been particularly described with respect to children and young adults and is illustrated with historical trading card examples, other applications may appeal to older adults and thus, the present invention provides an educational tool whereby medical students, law students, business students, etc. can acquire the requisite knowledge in their particular fields through a game playing method and system. [0027] Also incorporated herein by reference is U.S. Pat. No. 5,662,332 to Garfield. The present invention shares many characteristics with respect to the trading card game and method of play described in the Garfield patent, with the notably distinction that the Garfield patent is not directed to an educational tool for children, young adults and adults depending upon the subject matter being incorporated into the method and system. [0028] It is contemplated that the present invention can be used on existing and readily available electronic devices, such as computers, video games, electronic games, and on interactive networks utilizing computer software and text. Such electronic devices can visually display the cards and enable the players to manipulate the cards and execute turns as described hereinabove. Commercially available electronic communication devices can also be provided to enable players to communicate with each other over long distances. [0029] Still another version of the present game and method can be played using a playing board having pathways on it divided into squares on which the players can move. The pathways are preferably surrounded by colored areas and when two players meet on the same square in a land area, they dual by playing their own deck of cards against each other in accordance with the rules herein set forth or referred to by reference. [0030] Unlike the method set forth in the Garfield patent, the method of the present invention does not necessarily rely upon designating one or more game components being brought into play by rotating such game components from an original orientation to a second orientation. Moreover, the present method does not necessarily require that each player take one or more cards from an opposing player and place such cards on a playing surface. Whether significant differences exist between the present invention and that described in the Garfield patent include, in one embodiment, the elimination in the present invention of the altering of the state of a game element; the elimination of any defense elements that defend against a state-altering element and the absence of any modifying effect on other game elements as well as applicable rules during playing of a particular trading card game using the present invention. Most importantly, however, the present invention is principally directed to the dissemination and retention of useful historical knowledge by players whereas the Pokémon game is merely for entertainment purposes. The present method can therefore be seen to be directed to a method for educating children and young adults in an entertaining fashion whereas the Pokémon game is not at all directed to an educational tool. [0031] The present invention, referred to herein as “Historicon”, was created to be instructive as well as fun; an educational tool as well as a game. [0032] Historicon is a tool to understand and identify the persons, events, trends, creations, discoveries, that have made impacted and influenced their world. Historicon playing cards provide for the: comprehension and learning stimulation found in traditional educational flash cards; presentation of images and statistics; collecting fascination found in sports cards; and tactics and game play capability found in strategy card games. [0033] One aspect of the present invention provides people with a tool to understand, interpret, gauge, learn about the things that have shaped their world. Historicon assists students not only to find answers to questions, but to explore and begin asking questions. For example, Historicon addresses the questions that always seem to come at the end and beginning of a year, a decade, a century, a millennium, an age. It is important to ask questions on what has shaped these times. [0034] For example: [0035] who has impacted history in the past year? [0036] what event has marked the past decade? [0037] what is the most important invention of the century? [0038] who has had the most lasting influence in the past thousand years? [0039] Many people can only gauge the answers to these questions on their own experience and education. Even with experience and education these are still difficult questions to answer. Historicon Playing Cards, on one level, illustrate how rich the tapestry of human history is, and how the answer and questions are as numerous and as rich as human history. Historicon Playing Cards first identify a range of human influence, and on another level become an entertaining simulation or game. Players address questions that relate to History, as well as impact the way we think today. [0040] For example: [0041] did Beethoven has as much cultural impact as Elvis? [0042] who made a greater impact on science Copernicus or Einstein? [0043] who was the greater leader of men Caesar, Napoleon or Washington? [0044] who was the more creative inventor da Vinci or Edison? [0045] who was the greatest female leader Cleopatra or Elizabeth I? [0046] was the English victory over the Spanish Armada significant today? [0047] why is the Domesday Book important [0048] is Columbus really the greatest explorer? [0049] who is John Locke? Adam Smith? Mary Wollstonecraft? [0050] Why are these people important? [0051] Although the present invention can be presented on a computer, on-line, etc., it will generally be described herein in a card playing embodiment. Thus, in one embodiment, there are 3 types of Historicon Playing Cards: 1) Historicon Character Cards 2) Historicon Event Cards and 3) Historicon Scenario Cards. All cards have the same backing with the Historicon logo. Extensions to the game may have specialized backing. Within the above card classifications are a variety of other species which will be described below. [0052] In one particular embodiment, Historicon Character Cards are the main component cards of the present invention. These cards contain characters or subjects used in game play. Although historical characters are preferably used, other embodiments of the game may include mythological characters, characters from literature and legend, animals and plants etc. [0053] [0053]FIG. 3 shows a representative character card of the present invention and with respect to the components of the historicon character card, the cards themselves deal with the interaction of human history: art, music, science, exploration, government and war. [0054] The backing of the Historicon Playing Cards is preferably standard on all the cards, however (Historicon Character Cards, Event Cards, Scenario Cards). [0055] Extensions to the Historicon Playing Cards may show added details, e.g., Mythology series, Botany series, etc. as used herein. The term “Extension” will be understood to mean various possible variants, add ons, alternative Rules, that may be used in practicing the present invention. [0056] In a preferred embodiment, the names of characters in the main Historicon Playing Card game are Historical characters (Scientists, Explorers, Monarch etc. . . . ) that span the range of human history. [0057] Extensions of the Historicon Playing Cards may, however, contain names other than Historical characters: such as gods and goddesses in mythology characters in Legends Fictional character in Literature, Animals, Plants etc. . . . [0058] As discussed in the rules section, Historicon characters in extensions games will not interact with Historical figures since mythological, legendary, and fictional characters actions and accomplishments are not on the same level, and are played as separate game. For example, who had more impact on weather forecasting? It would not make sense to compare a historical meteorologist and a god of Thunder. [0059] The present invention identifies those individuals who have dominated and have had an impact and influence in their time and/or on the future. One aspect relates to ranking historical figures on their immediate and lasting importance/influence/impact on history, both positively and negatively. [0060] Although one will appreciate that various weighing and value judgments can be made, the following particular examples illustrate the more general concepts of the present invention. For example, in one embodiment, a 3-point system is used to weigh an individual's importance in their own lifetime (0-75 points), influence on history since their time (0-75 points), and specific impacting contributions to history (0-100 points). The best score a figure can receive is 250 points. [0061] Extensions for Historicon Playing Cards may have different Importance/influence/impact names. The mythology/legend series there might be “M.I.” for Mythological Importance or “M.P.” for Mythological Power and a different set of criteria. For example: How much a god or goddess influenced the development, philosophy of a culture or the power or importance a god or goddess held in a cultures mythology. [0062] An historical picture or drawing is preferably depicted on each card. Moreover, each card typically has a theme related color, and a place or nation where the cards character made his/her impact influence. This can be a place, city, a country or a continent(s). [0063] The card also contains more specific details which relates to a theme or title, for example, specific titles would be: [0064] Leaders: Monarch, King, Queen, Emperor, Empress, Sultan, Statesman, Senator, President, Chief, Captain etc. [0065] Warriors: General, Commander, Captain, Vizier, Admiral etc. [0066] Scientist: Astronomer, Chemist, Mathematician, Physicist etc. [0067] Inventors: Transportation, Industry etc. [0068] Explorers: Travelers, Aviator, Astronaut etc. [0069] Culture: Artist, Author, Philosopher, Musician, Entertainer etc. [0070] Extensions for Historicon Playing Cards may contain different specific information in the Nation and Theme Title Section. For Example a Mythology series may utilize this area for describing a specific mythology, for example, Norse Mythology, Greek Mythology. A Literature series may indicate what piece of literature a character is from, for example (Captain Nemo) Twenty Thousand Leagues . . . Jules Verne. Animals and Plant series may indicate a specific species, or scientific classification, or region of abundance. [0071] The present invention also preferably identifies contributions and events that historical characters have created and taken part in. For example, an Event/Contribution section of the Historicon Character Card lists the characters contributions and/or the events the character influenced and/or took part in. [0072] In one particular embodiment, there are 6 icons which reflect the themes used in Historicon and an aspect of Historicon which recognizes Wonders of the World or Wonders of human achievement. [0073] These icons are placed appropriately next to the specific contribution or event listing corresponding to the individual. [0074] Extensions of the Historicon Playing Cards may have Event/Contribution Icons overlap. For example, a Historicon Extension series which focuses on animals and plants may also relate to science. If animals played an important part of history, such as Elephants in the Punic Wars, then possibly the War/Defense Event Theme Icon may also apply next to that specific Event/Contribution Listing. The same can be said with animals in literature (Dogs in Call of the Wild by Jack London or Whales in Herman Melville's Moby Dick). If a plant is used for the manufacturing of certain industrial products, then the Invention/Industry Icon may apply next to that specific Event/Contribution Listing. [0075] Events/Contributions Listing, the specific contributions, events, and milestones which relate to specific individuals is set forth. For example, Contributions/Events can be categorized as: Leadership: Historical Documents; Acts of Leadership; Nations and Empires; Government Ideology; Specific Decisions; Reigns of Distinction. War & Defense: Wars; Battles; Weapons Science: Discoveries; Ideas; Movements. Inventions Industry: Inventions; Industries; Technologies. Exploration: Discovery of Place; Ages of Exploration Culture: Music; Books; Artwork; Ideas; Philosophy; Movements. [0076] Extensions of Historicon Playing Cards can display a variety of items in the Event/Contributions Listing section. For example, for plants and animals, their scientific names can be written: Kingdom.. Phylum.. Family.. Genus.. Species; Mythology may contain the god or goddess, patron city or temple, power of nature, special ability or weapon, tool etc. [0077] In one embodiment, Contribution/Event Scores are listed next to the individuals Events/Contribution Listing. Since these are listed from least to greatest impact or influence an Event/Contribution Score is illustrated that corresponds thereto. [0078] Scores are preferably incremented by 25, 50, 75, 100, and in rare occasion, 125. Occasionally characters who have contributed in one area (literature, science, exploration) may begin with a high score for achievement of 50 and decline by 10's for lesser achievements: 30, 40, 50. Additional points are added to these Scores by Historicon Event cards, which are also ranked by influence and importance. There is no limit to the contributions or events a person may have listed. Events/Contribution Listings are ranked top down from least to greatest in importance. In some instances an individual may have a singular impact which mark his or her influence, others may have several. [0079] Some characters may make a single contribution, or take part in a specific event. These Characters Score may be weighted by the significance of the specific contribution or role in the event. [0080] The Historicon Theme section illustrates how some characters left their mark in many areas. A card may therefore have different Event/Contribution Theme Icons that correspond with these Events/Contributions. Other characters may have left their impact and influence in a single field (Theme) and Events/Contributions Icons are then only represented from that field (Theme). Some characters will actually have multiple cards, representing the variety of impacts they made in their lifetime. For example Leonardo da Vinci was a scientist, artist, and inventor among other things. He may be featured in 3 separate cards each featuring his contributions to each of these themes. [0081] A further aspect of the present invention is directed to Character or Subject Fact/Text Fields. This section contains text that corresponds to the character represented. Text can contain historical fact, quotations, unknown tid-bits etc. Somewhere in the text can also show the birth/death date of the character. In one embodiment a code is used having a 5-digit number code that is specific to the Historicon Character Card. For example all Queen Elizabeth—Historicon Character Cards may have a Code Number of 47129. One aspect of the use of the 5 digit code is to facilitate use in Internet play. The ratio of cards may represented in an area of the card to indicate, for example, the number out of total number of Historicon Character Cards; the number out of cards in specific Theme: Leader Cards, Warrior Cards, Explorer Cards etc. . . . This area may also indicate whether a card is rare—meaning that due to the significance of the card there may be less of that card than others. [0082] Historicon Event Cards are essentially the reflections of the Event/Contribution Listings on the Historicon Character Cards. Typically, Historicon Event Cards serve several purposes: [0083] 1. Historicon Event Cards match with Event/Contribution Listings on the Historicon Character Cards, providing greater depth of understanding on the Events and Contributions made by the people on the Historicon Figure Cards. In other words, this card has added text which explains a characters contributions or a summary of the events the character influenced or took part in. [0084] 2. Historicon Event Cards add to the play-ability of the Historicon Playing Card Game by adding additional information and points to a Historicon Character Cards Event/Contribution Scores. [0085] 3. Some Historicon Event Cards will be Historicon Character Card specific such as Inventions and Discoveries made by a single person. For example: Thomas Edison: The Lightbulb. [0086] 4. Some Historicon Event Cards will be shared by many Historicon Character Cards. Events such as the Industrial Revolution, Age of Exploration, Renaissance, Wars, Battles etc. will be shared by many Historicon Character Cards. [0087] Additional Event Score ranks Events and Contributions on their impact and influence on human history. Lesser events, contributions and achievements may receive different scores, e.g., +10 or +15, whereas greater events, contributions and achievements may receive +25 or +50. When Historicon Event Cards are matched with the Event Contribution Listings on the Historicon Character cards the two scores are added for game play. [0088] In addition to a Picture/Drawing Image, each card also has a Text section gives more explanation of the actual Event/Contribution etc. [0089] A Title of the Historicon Event Card corresponds to the type or Theme of the Event Card. If the Event Cards contribution is the Spanish Armada, the Event Cards Theme is War and Defense. The Title at the Bottom of the Historicon Event Card will read Event Card: War Defense. Historicon Event Cards also correspond with the color given with the Event/Contribution Theme Icon. [0090] a. Example Leadership/Government Event Cards are as follows: Hammurabis Code Justinians Code Imperial Code Edict of Paris Legal Code of Taiho Capitulary of Herstal Admonito generalist Ordinatio Imperii Code Napoleon Declaration of Independence Bill of Rights Constitution Declaration of the Rights of Man Gettysburg Address New Deal The Prince The Spirit of Laws Common Sense Communist Manifesto Federalist Papers [0091] b. List of example War/Defense Event Cards: Battle of Hastings On War (Clausewitz) Armor Spanish Armada Art of War (Sun Tzu) Chariot Battle of Kadesh Walls Cavalry Battle of Marathon Towers Longbow Persian Wars Castles Catapults [0092] c. List of example Science/Technology Event Cards: Heliocentric Theory Decimal System Microscope Unified Theory Pythagorean Theorem Telescope Natural Selection Mayan Calender Electricity Continental Drift pi DNA Laws of Motion Speed of Sound Elements [0093] d. List of example Invention/Innovation/Industry Event Cards: Printing Press Wright Flyer Bessemer Steel Lightbulb Model T Child Labor Laws Toothbrush Steam Engine Textile Industry Computer Railroad Assembly Line Radio Kayak Factory System Silk Road Hanseatic League Hudson Bay Company Wealth of Nations Royal Exchange NY Stock Market [0094] e. List of example Exploration/Discovery Event Cards: H. M. S. Beagle Circumnavigation Ptolemys Map Santa Maria New World Compass H. M. S. Discovery Moon Landing Longitude Apollo 11 Mount Everest Chronometer Kon Tiki Source of the Nile Lateen Sail [0095] f. List of example Cultural Event Cards: Reformation Mona Lisa Book of Kells Globe Theater Gregorian Chants The Odyssey 9th Symphony Renaissance Sistine Chapel Kabuki Theater Buddhism Don Quixote Hamlet Divine Comedy Messiah [0096] In yet a further embodiment, Wonder Cards are used to represent specialized Event Cards. Wonder cards celebrate the creations and achievements of humans which can only be described as wonders. Wonders do not only encompass structures and monuments that are one of a kind, but human achievements as well. [0097] Wonders are extremely unique, and only on occasion may correspond with a Historicon Character Card. In this way Wonder cards themselves may be Extensions themselves to the Historicon Playing Card game. List of examples which can be considered as Wonder Cards is the 7 ancient wonders of the world: The Pyramids Hanging Gardens of Babylon Temple of Artemis at Ephesus Statue of Zeus at Olympia Mausoleum at Halicarnassus Colossus at Rhodes Lighthouse of Alexandria [0098] Other possible wonders include: Royal Tombs of Petra Moche Pyramids Tomb of Pakal, Palenque Angkor Wat Stonehenge Ziggurrat of Ur Temple of Karnak Temple of Abu Simbel The Parthenon Pyramid of the Sun Buddhist Caves, Ajanta Monks Mound, Cahokia Timbuktu Great Temple of the Aztecs Minoan Palace at Knossos Palace at Nineveh Palace of Persepolis Colosseum at Rome Hadrians Wall Great Zimbabwe Walls of Babylon Great Wall of China Masada Chinese Canals Roman Aqueducts Roman Roads Chaco Road System Inca Roads & Bridges Great Sphynx Egyptian Obelisks Olmec Heads Nazca Lines Easter Island Great Library of Oracle of Delphi Alexandria [0099] Modern: Flatiron Building Brooklynn Bridge Panama Canal Biffel Tower Sydney Opera House Sistine Chapel Shakespeares Globe Hoover Dam Golden Gate Bridge Statue of Liberty Empire State Building Alaskan Highway [0100] Historicon Playing Cards presently may be broken down into a variety of themes. For example, in one embodiment, six themes depict particular aspects of human cultural history. The Wonder Card, the 7th card, brings in the extraordinary feats of human achievement. [0101] As an example of the Themes used in the present invention, the following is presented. A. Leadership/Government [0102] The Leadership Theme encompasses those who have impacted history through the leadership and governing of peoples, clans, tribes, city-states, countries, nations, republics, empires etc. These may be monarchs, kings, queens, emperors, empresses, pharaohs, sultans, dictators, chancellors, prime ministers, presidents, senators, statesman, politicians, governors, mayors, chiefs, etc. . . The Leadership Theme category also includes those who have helped change and shape government, and influence and create leaders through ideas, action and law. This includes revolutionaries, patriots, ambassadors, diplomats, lawyers, political writers and thinkers etc. . . . [0103] Many leaders were influential leaders in war as well as in politics and may have a Historicon Character Card for both the Leadership Theme as well as the Generals/Warriors Theme. Example George Washington, Napoleon I, Andrew Jackson, Simon Bolivar etc. . . . [0104] Some leaders were patrons of the arts and culture, profited from colonization, trade, and exploration, and dabbled inthe sciences. These interests which crossover to other themes are recognized by multiple Event Theme Icons on their Historicon Character Card Event/Contribution Listing (see Graphic 4.) or a separate Historicon Character Card for that Theme. [0105] The Leadership Theme does include those who influenced history in a negative way. These characters although the cause of tremendous damage on history still impacted history and cannot be ignored. [0106] A List of character examples in a Leadership Theme Category include: Elizabeth I George Washington Thomas Paine Mehmed II Simon Bolivar Alexander Hamilton Isabella I Napoleon I Ben Franklin Sargon I Peter the Great Benjamin Disreali Cleopatra Alexander the Great Karl Marx Oliver Cromwell Moses Voltaire Winston Churchill Joseph Stalin Thomas Jefferson Caesar Catherine the Great George Marshall B. Warriors/Generals [0107] The Warrior/General Theme encompasses those who have impacted history through the leadership in battle, war, for gain or defense of their peoples, clans, tribes, city-states, countries, nations, republics, empires etc. The characters primarily for this Theme category are Commanders, Generals, Admirals, Captains, Colonels, Warriors, Soldiers, but may contain characters from other Theme categories especially the Leadership Theme category, since it is the leaders who either directly engage in war, make policy that leads to war, or become leaders of people from the spoils of war. This Theme category also contains those who have helped change and shape the face of war, and influence and create conflict through ideas and action. This includes writers, thinkers, scientists, inventors etc. . . . For example the policies of religious thinkers have led to numerous wars (The Crusades), and Alfred Nobels invention of smokeless gunpowder, and dynamite change the face of war forever. The results of war led to many innovations which benefitted society through innovations in science for example blood transfusions. Some master works of Literature have been directly inspired by the horrors of war. [0108] Many characters in the Warriors/Generals/Captains took part in expeditions and voyages of exploration. These items which crossover to other themes are recognized by multiple Event Theme Icons on their Historicon Character Card Event/Contribution Listing or another a separate Historicon Character Card for that Theme. [0109] The Warrior Theme does include those who influenced history in a negative way. These characters although the cause of tremendous damage on history still impacted history and cannot be ignored. [0110] A List of character examples in Warrior Theme Category include: Napoleon I Hannibal Queen Boudicca Charles Martel Joan of Arc Stonewall Jackson Frederick the Great Geronimo Molly Pitcher Attila the Hun Marc Antony Montezuma John Paul Jones Francis Drake W. T. Sherman Rommel Zhukov Patton C. Science [0111] The Science Theme encompasses those who have impacted history through scientific achievement, exploration and discovery. The characters primarily for this Theme category are Geologists, Botanists, Meteorologists, Zoologists, Naturalists, Astronomers, Biologists, Chemists, Physicists, Paleontologists, Mathematicians, and Physicians etc. The science of Geography is examined in more detail in the Explorers Theme, as is Political Science which is covered in the Leadership Theme, economics in the Invention Theme. [0112] Science Theme characters may overlap with characters from other Theme categories especially the Invention Theme category, since many scientific discoveries lead to inventions and innovations. There may be overlap as well with the Explorer Theme, since many expeditions are accompanied by scientists or accomplished through science. These items which crossover to other themes are recognized by multiple Event Theme Icons on their Historicon Character Card Event/Contribution Listing, or another a separate Historicon Character Card for that Theme. [0113] A List of character examples in Science Theme Category include: Albert Einstein Ben Franklin Leonardo da Vinci Marie Curie Galileo Gregor Mendel Copernicus Galen Louis Pasteur Ibn Sina William Harvey Isaac Newton Charles Darwin Edward Jenner Descartes Pythagoras Hypatia Archimedes Leeuwenhoek Robert Goddard Charles Lyell Kepler Carl Jung Elizabeth Blackwell Fibiola Pascal Thomas Jefferson Francis Bacon Carl Linnaeus Niels Bohr D. Inventors/Innovators/Industry [0114] The Inventors/Innovators/Industry Theme encompasses those who have created inventions to improve the way we live and those who have turned these inventions into industries which have impacted the way we live. The characters primarily for this Theme category are the inventors and giants of industry. In the middle this Theme also cover Business and Economics and the characters who transport ideas and goods from place to place. [0115] The Invention Theme encompasses primarily inventors; inventors and innovators in communications and transportation fields; innovators, or those who have improved and spread an invention to wide public use; industry, or those dealing with materials, goods, energy, process, product, social and economics of workers and consumers; and those dealing with the transport of goods and ideas; traders and merchants, and those who set up colonies and business ventures as well; businessmen and investors. [0116] Invention Theme characters may overlap with characters from other Theme categories especially the Science Theme category, since many inventions come from science. There may be overlap as well with the Explorer Theme, since many explorers and travelers are the vessels of goods, and ideas which inspire invention, innovation, and industry. These items which crossover to other themes are recognized by multiple Event Theme Icons on their Historicon Character Card Event/Contribution Listing, or another a separate Historicon Character Card for that Theme. [0117] A list of character examples in Invention/Innovation/Industry Category include: Johann Gutenberg Thomas Edison Marco Polo Archimedes Alexander G. Bell J. P. Morgan Eli Whitney Leonardo da Vinci Carnegie Lorenzo de Medici Robert Fulton Henry Ford Wilbur Wright Orville Wright Carl Benz Henry Bessemer Edmund Cartwright Adam Smith Robert Owens John Maynard Keynes James Watt Walter Raleigh Thomas Gresham Daguerre Ben Franklin John Eckert Alfred Nobel Michael Faraday Petrus Peregrinus Marconi E. Explorers [0118] The Explorers Theme encompasses those who have impacted history through exploration and discovery. The characters primarily for this Theme come from almost all the other Theme categories. Leaders occasionally enter strange and unknown lands and open the world to a greater understanding as did Alexander the Great. Leaders also fund expeditions in the name of territorial gain, riches, and occasionally scientific discovery, such as Henry the Navigator, Queen Isabella, Queen Elizabeth, and Queen Victoria. Warriors are often named explorers because they are the ones opening a region for colonization as in the case of Cortes and Pizzaro. Scientists are often named explorers because they accompany expeditions and voyages of discovery as in the case of Charles Darwin. In the Invention/Industry category traders and merchants are often the one who also carry tales of foreign places and in the end labeled by history as travelers and adventurers as in the case of Marco Polo. [0119] The Explorer Theme Category encompasses the field of geography and may include characters which have produced maps, instruments, and written on the field of geography. The Explorer Theme Category also encompasses those who have done pioneering feats- for example solo flight across the Atlantic, first to summit Mount Everest, set foot on the Moon, reach the South Pole, row across the Atlantic etc. Explorer Theme characters may overlap with characters from other Theme categories. These items which crossover to other themes are recognized by multiple Event Theme Icons on their Historicon Character Card Event/Contribution Listing, or another a separate Historicon Character Card for that Theme. [0120] A list of character examples in Explorer Theme Category include: Ferdinand Magellan Marco Polo Henry the Navigator Christopher Columbus James Cook Isabella Vasco da Gama Francis Drake Richard Burton Edmund Hillary Coronado Zheng He Erik the Red Lief Ericson Charles Darwin Daniel Boone Zeb. Pike Neil Armstrong Hernan Cortes Abel Tasman Livingstone Amelia Earhart Pedro Cabral Mercator Ptolemy Peary Adm. Byrd C. Culture [0121] The Culture Theme encompasses those who have impacted history through the beauty and intelligence of culture. The characters primarily for this Theme category are Artists, Architects, Musicians, Writers of Literature, Poetry and Plays, Entertainers, Philosophers and Thinkers. [0122] Culture Theme characters may overlap with characters from other Theme categories especially the Leadership Theme category, since many Leaders are patrons of the arts. Leaders are also inspired, enshrined and dethroned by the works of the Cultural Theme. Warriors may cross paths with the Culture Theme in negative ways since art is destroyed, censored or stolen in times of war. However war has inspired masterpieces of art music and writing. These items which crossover to other themes are recognized by multiple Event Theme Icons on their Historicon Character Card Event/Contribution Listing (see Graphic 4.), or another a separate Historicon Character Card for that Theme. [0123] A list of character examples in Culture Theme Category include: William Shakespeare Michelangelo Lorenzo de Medici Christopher Wren Beethoven P. T. Barnum Homer Cezanne Erasmus Frank Lloyd Wright Bach Sarah Bernhardt John Milton Monet Petrarch Martin Luther King Jr. Brothers Grimm Mozart Leonardo da Vinci Gandhi Lucretia Mott Seneca Handel Rembrandt [0124] The examples provided in the above lists are in no way complete, nor show the best of each Theme category. They are examples of what one might find in the Historicon Playing Card Game. [0125] While various embodiments of the present invention have been described in detail, it is apparent that further modifications and adaptations of the invention will occur to those skilled in the art. However, it is to be expressly understood that such modifications and adaptations are within the spirit and scope of the present invention.

An educational trading card game involves the use of a plurality of cards having graphic representations of the events, persons and/or concepts associated therewith. The educational trading cards have various colors, shapes, sizes, numerical representations and various informational content associated therewith which enable a game player, in accordance with a particular set of rules, to acquire as many trading cards as possible to accomplish “winning” of particular game rounds with one or more opponent players. In one embodiment, the trading card system and method of the present invention is predicated upon the Pokémon trading card game rules and procedures but is distinguished by having educational content associated with such cards.