Pub Date : 1992-10-25DOI: 10.1109/NSSMIC.1992.301117
K. Yamamoto, M. Muramatsu, K. Yamamura, M. Ohmura, H. Utsuyama, H. Anzai, Y. Hayama
Evaluation devices of a double-sided silicon strip detector have been fabricated. These devices are basically AC-coupled and mainly designed to study the stability and reliability of a coupling capacitor to maintain low noise, high breakdown voltage. A hot electron analyzer was used to check the relation between breakdown voltage and charge injection in the coupling capacitor.<>
{"title":"Stability and reliability of the double sided silicon strip detector","authors":"K. Yamamoto, M. Muramatsu, K. Yamamura, M. Ohmura, H. Utsuyama, H. Anzai, Y. Hayama","doi":"10.1109/NSSMIC.1992.301117","DOIUrl":"https://doi.org/10.1109/NSSMIC.1992.301117","url":null,"abstract":"Evaluation devices of a double-sided silicon strip detector have been fabricated. These devices are basically AC-coupled and mainly designed to study the stability and reliability of a coupling capacitor to maintain low noise, high breakdown voltage. A hot electron analyzer was used to check the relation between breakdown voltage and charge injection in the coupling capacitor.<<ETX>>","PeriodicalId":447239,"journal":{"name":"IEEE Conference on Nuclear Science Symposium and Medical Imaging","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1992-10-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133442404","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1992-10-25DOI: 10.1109/NSSMIC.1992.301437
N. Cartiglia, D. Dorfan, D. Pitzl, J. Rahn, W. Rowe, H. Sadrozinski, E. Spencer, M. Wilde, M. Turala, W. Dąbrowski
The authors present radiation hardness measurements of both small-scale bipolar test structures and full amplifier-comparator circuits built in the Tektronix SHPi process. BJTs (bipolar junction transistors (npm of various sizes and a lateral pnp), JFETs (junction field effect transistors), diodes, and resistors have been irradiated to /sup 60/Co doses of up to 5 Mrad and to fluences of up to 1.1*10/sup 14/ cm/sup -2/ of 650 MeV protons. Radiation effects on transistor noise and current gain, the value of the pinch-off voltage and output resistance of the JFET, leakage of diodes, and resistor values are discussed. A full 64-channel amplifier-comparator circuit was exposed to 3.5 Mrad of gammas, and changes in gain and noise were measured. It is concluded that the Tektronix SHPi process appears to offer sufficient radiation hardness for the design of fast, low-power amplifier circuits for the Superconducting Super Collider.<>
{"title":"Radiation hardness measurements on bipolar test structures and an amplifier-comparator circuit","authors":"N. Cartiglia, D. Dorfan, D. Pitzl, J. Rahn, W. Rowe, H. Sadrozinski, E. Spencer, M. Wilde, M. Turala, W. Dąbrowski","doi":"10.1109/NSSMIC.1992.301437","DOIUrl":"https://doi.org/10.1109/NSSMIC.1992.301437","url":null,"abstract":"The authors present radiation hardness measurements of both small-scale bipolar test structures and full amplifier-comparator circuits built in the Tektronix SHPi process. BJTs (bipolar junction transistors (npm of various sizes and a lateral pnp), JFETs (junction field effect transistors), diodes, and resistors have been irradiated to /sup 60/Co doses of up to 5 Mrad and to fluences of up to 1.1*10/sup 14/ cm/sup -2/ of 650 MeV protons. Radiation effects on transistor noise and current gain, the value of the pinch-off voltage and output resistance of the JFET, leakage of diodes, and resistor values are discussed. A full 64-channel amplifier-comparator circuit was exposed to 3.5 Mrad of gammas, and changes in gain and noise were measured. It is concluded that the Tektronix SHPi process appears to offer sufficient radiation hardness for the design of fast, low-power amplifier circuits for the Superconducting Super Collider.<<ETX>>","PeriodicalId":447239,"journal":{"name":"IEEE Conference on Nuclear Science Symposium and Medical Imaging","volume":"43 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1992-10-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133445384","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1992-10-25DOI: 10.1109/NSSMIC.1992.301442
M. Holler, A. Shmurun, S. Tam, J. Brauch
A system is presented which can classify unknown objects by the waveform produced upon their impact with a known object. The output of an accelerometer mounted on the known object is read into a unit that computes the waveform's discrete Fourier transform (DFT), which is then fed into a two-layer neural network recognition module. The specific application described observes a collision between two objects, one of which is a wooden platform while the other is made out of a different material. After being shown sample waveforms produced by collisions with three types of objects, the system can then classify new collisions with the objects within 6 ms after the impact. Both the DFT unit and the classification network are implemented with Intel's 80170NX Electrically Trainable Analog Neural Network (ETANN).<>
{"title":"Neural network recognition of objects based on impact dynamics","authors":"M. Holler, A. Shmurun, S. Tam, J. Brauch","doi":"10.1109/NSSMIC.1992.301442","DOIUrl":"https://doi.org/10.1109/NSSMIC.1992.301442","url":null,"abstract":"A system is presented which can classify unknown objects by the waveform produced upon their impact with a known object. The output of an accelerometer mounted on the known object is read into a unit that computes the waveform's discrete Fourier transform (DFT), which is then fed into a two-layer neural network recognition module. The specific application described observes a collision between two objects, one of which is a wooden platform while the other is made out of a different material. After being shown sample waveforms produced by collisions with three types of objects, the system can then classify new collisions with the objects within 6 ms after the impact. Both the DFT unit and the classification network are implemented with Intel's 80170NX Electrically Trainable Analog Neural Network (ETANN).<<ETX>>","PeriodicalId":447239,"journal":{"name":"IEEE Conference on Nuclear Science Symposium and Medical Imaging","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1992-10-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132724716","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1992-10-25DOI: 10.1109/NSSMIC.1992.301421
K.B. Cellars, J. Spina, M.A. Elzey, E. F. McGinn, M. Winsor
Baltimore Gas and Electric's (BG&E's) approach to implementing an automated procurement engineering process is presented. The process emphasizes part safety classification, procurement specification, and warehouse description standardization, of a limited population of the most frequently procured parts (stocked replacement items for safety-related systems, structures, and components). Logical grouping of over 10000 stock items resulted in consolidation to 275 automated procurement specifications maintained through a PC-based computer application. This automation has resulted in the following cost benefits: reduced procurement engineering staff, reduced procurement request backlog, reduced volume of bid exceptions/deviations, and elimination of duplicate stocked items.<>
{"title":"Implementing automated procurement engineering at BG&E","authors":"K.B. Cellars, J. Spina, M.A. Elzey, E. F. McGinn, M. Winsor","doi":"10.1109/NSSMIC.1992.301421","DOIUrl":"https://doi.org/10.1109/NSSMIC.1992.301421","url":null,"abstract":"Baltimore Gas and Electric's (BG&E's) approach to implementing an automated procurement engineering process is presented. The process emphasizes part safety classification, procurement specification, and warehouse description standardization, of a limited population of the most frequently procured parts (stocked replacement items for safety-related systems, structures, and components). Logical grouping of over 10000 stock items resulted in consolidation to 275 automated procurement specifications maintained through a PC-based computer application. This automation has resulted in the following cost benefits: reduced procurement engineering staff, reduced procurement request backlog, reduced volume of bid exceptions/deviations, and elimination of duplicate stocked items.<<ETX>>","PeriodicalId":447239,"journal":{"name":"IEEE Conference on Nuclear Science Symposium and Medical Imaging","volume":"41 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1992-10-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133186964","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1992-10-25DOI: 10.1109/NSSMIC.1992.301094
A. Paans, J. Schippers
To evaluate the possibility of combining proton therapy with positron emission tomography (PET) as a therapy monitor and as a tool for in situ dosimetry during therapy, proton activation experiments have been performed using a 55-MeV proton beam on two different materials. The three-dimensional measurements of the induced activity with PET are compared with the calculated dose distribution and with model calculations. It is concluded that the radioactivity induced by proton beams in tissue-like (consisting mainly of C, N and O) materials can be measured accurately by means of PET. It is expected that the rather low amount of activity created during a therapy treatment can be detected with sufficient accuracy; in particular, the region preceding the Bragg peak in the dose distribution can be monitored quite well with this method.<>
{"title":"Proton therapy in combination with PET as monitor: a feasibility study","authors":"A. Paans, J. Schippers","doi":"10.1109/NSSMIC.1992.301094","DOIUrl":"https://doi.org/10.1109/NSSMIC.1992.301094","url":null,"abstract":"To evaluate the possibility of combining proton therapy with positron emission tomography (PET) as a therapy monitor and as a tool for in situ dosimetry during therapy, proton activation experiments have been performed using a 55-MeV proton beam on two different materials. The three-dimensional measurements of the induced activity with PET are compared with the calculated dose distribution and with model calculations. It is concluded that the radioactivity induced by proton beams in tissue-like (consisting mainly of C, N and O) materials can be measured accurately by means of PET. It is expected that the rather low amount of activity created during a therapy treatment can be detected with sufficient accuracy; in particular, the region preceding the Bragg peak in the dose distribution can be monitored quite well with this method.<<ETX>>","PeriodicalId":447239,"journal":{"name":"IEEE Conference on Nuclear Science Symposium and Medical Imaging","volume":"12 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1992-10-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133209166","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1992-10-25DOI: 10.1109/NSSMIC.1992.301289
D. Panescu, T. Górski, Y. Hu, J. Lackey, P. Robl, W.H. Smith
A four 12-bit numbers adder fabricated using a 1.2 mu m N-well CMOS process is presented. It is proposed for use in the computation of the pipelined energy sums in the detectors at the Superconducting Super Collider (SSC). It comprises three 12-bit adders organized as a two-stage pipeline. To compute the final carry bit, the carry-select technique applied to five 4-bit adders is used. The 4-bit adders use the carry-lookahead method to compute their carriers. In order to reduce the circuit area and to simplify its structure the multiple-output domino logic design style is used. The first stage of the pipeline (two adders) performs two 12-bit additions in parallel while the second stage (one adder) finishes up the previously started computation. The pipeline is driven using a two-phase clocking strategy by processing a single-phase external clock. A worst-case throughput of 18 ns is achieved. A built-in facility for testing the first stage of the pipeline is included. The area of the circuit is 1425*5510 mu m/sup 2/; it has 76 pads; and it was packed in a 132 PGA. The transistor count is 6639. The dissipated power, at 18-ns clock, is approximately=0.75 W. The circuit has been fabricated through MOSIS, and a yield of approximately=80% for a lot of 50 chips was found.<>
介绍了一种采用1.2 μ m n阱CMOS工艺制作的4位12位数字加法器。提出了一种用于超导超级对撞机(SSC)探测器管道能量和计算的方法。它由三个12位加法器组成，分为两级管道。为了计算最后的进位，使用了适用于五个4位加法器的进位选择技术。4位加法器使用超前进位法来计算它们的载波。为了减小电路面积和简化电路结构，采用了多输出多米诺逻辑设计方式。管道的第一阶段(两个加法器)并行执行两个12位加法，而第二阶段(一个加法器)完成先前开始的计算。通过处理单相外部时钟，采用两相时钟策略驱动管道。实现了18ns的最坏吞吐量。包括用于测试管道第一阶段的内置设施。电路面积为1425*5510 μ m/sup 2/;它有76个垫子;装在132pga里。晶体管数是6639。在18ns时钟下，耗散功率约为=0.75 W。该电路已通过MOSIS制造，并且发现50个芯片的产率约为80%
{"title":"A pipelined 4 by 12-bits domino logic VLSI adder","authors":"D. Panescu, T. Górski, Y. Hu, J. Lackey, P. Robl, W.H. Smith","doi":"10.1109/NSSMIC.1992.301289","DOIUrl":"https://doi.org/10.1109/NSSMIC.1992.301289","url":null,"abstract":"A four 12-bit numbers adder fabricated using a 1.2 mu m N-well CMOS process is presented. It is proposed for use in the computation of the pipelined energy sums in the detectors at the Superconducting Super Collider (SSC). It comprises three 12-bit adders organized as a two-stage pipeline. To compute the final carry bit, the carry-select technique applied to five 4-bit adders is used. The 4-bit adders use the carry-lookahead method to compute their carriers. In order to reduce the circuit area and to simplify its structure the multiple-output domino logic design style is used. The first stage of the pipeline (two adders) performs two 12-bit additions in parallel while the second stage (one adder) finishes up the previously started computation. The pipeline is driven using a two-phase clocking strategy by processing a single-phase external clock. A worst-case throughput of 18 ns is achieved. A built-in facility for testing the first stage of the pipeline is included. The area of the circuit is 1425*5510 mu m/sup 2/; it has 76 pads; and it was packed in a 132 PGA. The transistor count is 6639. The dissipated power, at 18-ns clock, is approximately=0.75 W. The circuit has been fabricated through MOSIS, and a yield of approximately=80% for a lot of 50 chips was found.<<ETX>>","PeriodicalId":447239,"journal":{"name":"IEEE Conference on Nuclear Science Symposium and Medical Imaging","volume":"156 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1992-10-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134484160","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1992-10-25DOI: 10.1109/NSSMIC.1992.301406
N. Porter
The application of adjustable speed drive technology at a nuclear plant is described. The 8900 hp reactor recirculating coolant pump motors will be driven by a GTO-PWM (gate turn-off pulse-width-modulated) drive rated at 11200 hp.<>
{"title":"Adjustable speed drives in nuclear applications","authors":"N. Porter","doi":"10.1109/NSSMIC.1992.301406","DOIUrl":"https://doi.org/10.1109/NSSMIC.1992.301406","url":null,"abstract":"The application of adjustable speed drive technology at a nuclear plant is described. The 8900 hp reactor recirculating coolant pump motors will be driven by a GTO-PWM (gate turn-off pulse-width-modulated) drive rated at 11200 hp.<<ETX>>","PeriodicalId":447239,"journal":{"name":"IEEE Conference on Nuclear Science Symposium and Medical Imaging","volume":"11 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1992-10-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115391429","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1992-10-25DOI: 10.1109/NSSMIC.1992.301147
R. Wagner, J. R. Joseph, R. Hilko, R. Harper, J. Tinsley
The temporal response, relative proton-to-gamma ratio, and relative sensitivity of photoconductive detectors made in identical physical geometries from natural Class IIa diamond and from neutron-irradiated GaAs were measured. The temporal response of the diamond detectors varied from 145 to 360 ps FWHM for a 30 ps, 16 MeV end-point bremsstrahlung pulse. This response compares to 103 ps FWHM for the GaAs detectors. Proton-to-gamma ratios for the diamond detectors were three times those of the GaAs detectors. The relative sensitivities of the diamond detectors, compared with those in the GaAs detectors, were 0.5 to 0.7. The leakage current of the diamond detectors was at least three orders of magnitude lower than those in the GaAs devices. The temporal response of neutron-irradiated diamond detector was 90 ps FWHM, a significant improvement in speed over natural diamond.<>
{"title":"The temporal response and relative proton-to-gamma ratio of radiation detectors made from natural diamond","authors":"R. Wagner, J. R. Joseph, R. Hilko, R. Harper, J. Tinsley","doi":"10.1109/NSSMIC.1992.301147","DOIUrl":"https://doi.org/10.1109/NSSMIC.1992.301147","url":null,"abstract":"The temporal response, relative proton-to-gamma ratio, and relative sensitivity of photoconductive detectors made in identical physical geometries from natural Class IIa diamond and from neutron-irradiated GaAs were measured. The temporal response of the diamond detectors varied from 145 to 360 ps FWHM for a 30 ps, 16 MeV end-point bremsstrahlung pulse. This response compares to 103 ps FWHM for the GaAs detectors. Proton-to-gamma ratios for the diamond detectors were three times those of the GaAs detectors. The relative sensitivities of the diamond detectors, compared with those in the GaAs detectors, were 0.5 to 0.7. The leakage current of the diamond detectors was at least three orders of magnitude lower than those in the GaAs devices. The temporal response of neutron-irradiated diamond detector was 90 ps FWHM, a significant improvement in speed over natural diamond.<<ETX>>","PeriodicalId":447239,"journal":{"name":"IEEE Conference on Nuclear Science Symposium and Medical Imaging","volume":"104 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1992-10-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115586021","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1992-10-25DOI: 10.1109/NSSMIC.1992.301065
K. R. Pollard, A. Bice, L. Durack, T. Lewellen, R. Miyaoka, S. Kohlmyer
Gamma camera imaging of I-131 suffers from detection of Compton-scattered events. Many different methods of scatter correction have been proposed for lower-energy radionuclide (e.g., Tc-99m) imaging. Extension of these scatter corrections to I-131 imaging is not obvious and may not be simple, because a significant fraction of the detected scatter is due to gamma rays that have scattered in the camera-head. The authors acquired list-mode data (x, y and E) from a digital gamma camera and rebinned it in different ways to compare five different scatter-correction techniques: lower-window subtraction, upper-window subtraction, upper and lower window subtraction, linear dual photopeak, and nonlinear dual photopeak. A lower, Compton-window subtraction appears most stable, and perhaps best.<>
{"title":"Using list-mode data to compare scatter corrections in I-131 imaging","authors":"K. R. Pollard, A. Bice, L. Durack, T. Lewellen, R. Miyaoka, S. Kohlmyer","doi":"10.1109/NSSMIC.1992.301065","DOIUrl":"https://doi.org/10.1109/NSSMIC.1992.301065","url":null,"abstract":"Gamma camera imaging of I-131 suffers from detection of Compton-scattered events. Many different methods of scatter correction have been proposed for lower-energy radionuclide (e.g., Tc-99m) imaging. Extension of these scatter corrections to I-131 imaging is not obvious and may not be simple, because a significant fraction of the detected scatter is due to gamma rays that have scattered in the camera-head. The authors acquired list-mode data (x, y and E) from a digital gamma camera and rebinned it in different ways to compare five different scatter-correction techniques: lower-window subtraction, upper-window subtraction, upper and lower window subtraction, linear dual photopeak, and nonlinear dual photopeak. A lower, Compton-window subtraction appears most stable, and perhaps best.<<ETX>>","PeriodicalId":447239,"journal":{"name":"IEEE Conference on Nuclear Science Symposium and Medical Imaging","volume":"102 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1992-10-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114490181","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1992-10-25DOI: 10.1109/NSSMIC.1992.301507
K. Ogawa, N. Nishizaki
The authors present a novel method for estimating primary photons using an artificial neural network in radionuclide imaging. The neural network for Tc-99m has three layers, one input layer with five units, one hidden layer with five units, and one output layer with two units. As input values to the input units, count ratios were used which were the ratios of the counts acquired by narrow windows to the total count acquired by a broad window with the energy range from 125 to 154 keV. The outputs were a scatter count ratio and a primary count ratio. Using the primary count ratio and the total count, the primary count of the pixel was calculated directly. The neural network was trained with a backpropagation algorithm using calculated true energy spectra obtained by a Monte Carlo method. The simulation showed that accurate estimation of primary photons was accomplished within an error ratio of about 3% for primary photons.<>
{"title":"A sophisticated estimation of scatter component in energy spectra using an artificial neural network in radionuclide imaging","authors":"K. Ogawa, N. Nishizaki","doi":"10.1109/NSSMIC.1992.301507","DOIUrl":"https://doi.org/10.1109/NSSMIC.1992.301507","url":null,"abstract":"The authors present a novel method for estimating primary photons using an artificial neural network in radionuclide imaging. The neural network for Tc-99m has three layers, one input layer with five units, one hidden layer with five units, and one output layer with two units. As input values to the input units, count ratios were used which were the ratios of the counts acquired by narrow windows to the total count acquired by a broad window with the energy range from 125 to 154 keV. The outputs were a scatter count ratio and a primary count ratio. Using the primary count ratio and the total count, the primary count of the pixel was calculated directly. The neural network was trained with a backpropagation algorithm using calculated true energy spectra obtained by a Monte Carlo method. The simulation showed that accurate estimation of primary photons was accomplished within an error ratio of about 3% for primary photons.<<ETX>>","PeriodicalId":447239,"journal":{"name":"IEEE Conference on Nuclear Science Symposium and Medical Imaging","volume":"102 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1992-10-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114523919","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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