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Medical Imaging II 1988

作者： Aarsvold, J.N. Barrett, H.H. Chen, J. Landesman, A.L. Milster, T.D. Patton, D.D. Roney, T.J. Rowe, R.K. Seacat, R.H. Strimbu, L.M. University of Arizona Program in Applied Mathematics TucsonAZ85721 United States University of Arizona Optical Sciences Center TucsonAZ85721 United States University of Arizona Department of Radiology University Medical Center TucsonAZ85724 United States University of Arizona Department of Physics TucsonAZ85721 United States IBM Corporation General Products Division Department 78G/21-2 TucsonAZ85744 United States University of Arizona Department of Electrical and Computer Engineering TucsonAZ85721 United States

Modular scintillation cameras are gamma cameras with relatively small crystal faces, a small number of photomultiplier tubes (PMTs), and independent processing electronics. Our prototypical module has a 10 cm square crystal face, four PMTs, and digital processing electronics. Scintillation event information is transferred to images by mapping digitized PMT response combinations to optimal position estimates of event locations. In our prototype, a look-up table is used to perform this mapping. To encode scintillation event information more effectively, we use nonlinear compression of each of the PMT signals. Also introduced are logarithmic matched filtering and likelihood windowing, two processing techniques that result from exploitations of the Poisson model of the distribution of photopeak events. Logarithmic matched filtering is a method of obtaining estimates of mean detector response functions having greater accuracy than that indicated by the digitization of the PMT responses. Likelihood windowing is the utilization of a likelihood threshold, rather than the familiar energy window, as a discriminant of photopeak and scatter events. We have implemented each of the above on our prototypical module. Performance characteristics of this module include energy resolution of 10% full width at half maximum (FWHM) at 140 keV and spatial resolution of better than 4mm FWHM over 90% of the crystal. © 1988 SPIE. All rights reserved.

关键词： Photomultipliers

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Application of Interval Analysis Techniques to Linear Systems

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IFAC Proceedings Volumes 1987年第5期20卷 251-256页

作者： A.N. Michel E.P. Oppenheimer Department of Electrical and Computer Engineering University of Notre Dame Notre Dame IN 46566 USA Johns Hopkins University Applied Physics Laboratory Johns Hopkins Road Laurel MD 20707 USA

We apply interval analysis techniques to linear dynamical systems endowed with a parameter which belongs to an interval. For such systems, we obtain new algorithmic results which yield solution envelopes. In doing so, we also establish several new results for continuous interval functions, rational interval functions and exponential interval functions. The application of our results to several specific examples suggests that our algorithm yields tight bounds.

关键词： Interval analysis Linear differential equations Linear systems with a parameter in an interval Solution envelopes

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Some results in optimal hierarchical estimation

Some results in optimal hierarchical estimation

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IEEE Conference on Decision and Control

作者： S. Roy P. Bhimasankaram R. A. Iltis Department of Electrical and Computer Engineering University of California Santa Barbara CA USA Statistics and Applied probability program University of California Santa Barbara CA USA

The primary objective of this paper is to review several results available in the statistical literature pertaining to the problem of hierarchical estimation. Some relevant extensions are derived for the problem of reconstructing the globally optimal estimate based on local estimates transmitted by feeder nodes. Their utilisty is next demonstrated with characterizations and examples pertaining to common scenarios in decentralized estimation problems.

关键词： Sensor systems Noise measurement Optimal control Sensor phenomena and characterization Signal processing Costs Fault tolerant systems Sensor fusion Particle measurements Statistics

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Adaptive Target Tracking

Adaptive Target Tracking

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American Control Conference (ACC)

作者： P. R. Kalata G. C. Konstanzer D. Birnbaum Electrical and Computer Engineering Department Drexel University Philadelphia PA USA Applied Physics Laboratory Johns Hopkins University Laurel MD USA Systems Division Naval Air Development Center Warminster PA

The minimum time of detection as well as the track accuracy (time/accuracy profile) of a maneuvering target in an adaptive tracking system is consider. The maneuver detection schemes considered are the optimal stopping (OS), residual squared (RS) error, and direct acceleration estimation (DAE) algorithms. The transition-into-track considers optimal two and three point unbiased initiation processes.

关键词： Target tracking Acceleration Testing Hydrogen physics computing Laboratories Adaptive systems Detectors OFDM modulation Stochastic processes

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AIR-CUSHION LANDING CRAFT NAVIGATION

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NAVAL ENGINEERS JOURNAL 1985年第4期97卷 248-260页

作者： GRAHAM, HR KIM, JC BAND, EGU FOWLER, AW Herbert R. Graham:received his degrees of B.S. in 1951 and M.S. in 1958 in aeronautical engineering from the Massachusetts Institute of Technology and the California Institute of Technology respectively. He also attended the Harvard Graduate School of Business Administration. He is presently a task manager at TRW Inc. McLean Virginia responsible for landing craft air cushion (LCAC) engineering support. Since joining TRW in 1967 he has had several technical project management and system engineering responsibilities in amphibious ships transportation and energy. He was responsible for the preliminary engineering design and cost estimates for tracked air cushion vehicles (TACVs). He has been active in several professional societies including ASNE and served as vice-chairman Los Angeles Section American Institute of Aeronautics and Astronautics. John C. Kim:received his degrees of B.S. in electrical engineering Tri-State University 1959 M.S. in electrical engineering Michigan State University 1960 and Ph.D. in electrical engineering Michigan State University. He is presently a senior staff engineer with TRW Inc. McLean Virginia where his technical experience has included communications system engineering and navigation system analysis. Since joining TRW in 1969 he has held numerous positions including section head project manager and department manager. His previous employment includes E-Systems/Melpar Division and Honeywell. Dr. Kim has been active in the IEEE Washington Chapter activities which included secretary vice-chairman and chairman of Systems Science and Cybernetics Group. Edward G.U. Band:received a B.S. degree in mechnical engineering in 1946 and a D.I.C in aeronautical engineering in 1947 at the City and Guilds College of London University. In 1951 he received an M.S. degree from Stevens Institute of Technology in fluid dynamics. After a career in the aircraft industry in England Canada and the U.S.A. he spent several years teaching in Chile and at Webb Institute of Naval Archi

Air cushion vehicles (ACVs) have operated successfully on commercial routes for about twenty years. The routes are normally quite short; the craft are equipped with radar and radio navigation aids and maintain continuous contact with their terminals. Navigation of these craft, therefore, does not present any unusual difficulty. The introduction of air cushion vehicles into military service, however, can present a very different picture, especially when external navigation aids are not available and the craft must navigate by dead reckoning. This paper considers the problems involved when navigating a high-speed air cushion vehicle by dead reckoning in conditions of poor visibility. A method is presented to assess the ACV's navigational capability under these circumstances. A figure of merit is used to determine the sensitivity of factors which affect navigation such as the range of visibility, point-to-point distance, speed, turning radius and accuracy of onboard equipment. The method provides simplistic but adequate answers and can be used effectively to compare the-capability and cost of alternative navigation concepts.

关键词： AIR CUSHION VEHICLES

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Imaging system response linearization and shading correction

Imaging system response linearization and shading correction

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IEEE International Conference on Robotics and Automation (ICRA)

作者： I. Dinstein F. Merkle Tinwai Lam Kwan Wong Electrical and Computer Engineering Department Ben-Gurion University of the Negev Israel Institute of Applied Physics I University of Heidelberg Heidelberg Germany IBM Research Laboratory San Jose CA

Shading correction of image sensors is a very important operation in visual inspection applications. The generation and application of shading correction with and without imaging system response linearization is discussed and demonstrated. The linearization is achieved by subtracting the dark current image and by applying a lookup table operation. The content of the lookup table is obtained by fitting an analytical function to the measured system response. The linearization enables the shading correction to be a linear operation. The quality of the linearization and the shading correction was evaluated using statistical parameters of the processed images. The results showed a substantial decrease in the standard deviation of the gray level distribution of uniform reference images.

关键词： Cameras Laboratories Image sensors Inspection Table lookup Microscopy Lighting Optical distortion Optical imaging Dark current

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AN ADVANCED METHODOLOGY FOR PRELIMINARY HULL FORM DEVELOPMENT

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NAVAL ENGINEERS JOURNAL 1984年第4期96卷 147-161页

作者： LIN, WC DAY, WG HOUGH, JJ KEANE, RG WALDEN, DA KOH, IY Wen-Chin Lin:heads the Ship Powering Division at the David Taylor Naval Ship R&D Center (DTNSRDC). Dr. Lin received his B.S. degree in mechanical engineering from the National Taiwan University in 1957. He was awarded his M.S. degree in naval architecture and Ph.D. in engineering science from the University of California at Berkeley in 1963 and 1966 respectively. From 1966 to 1969 he was employed by ESSO Research and Engineering Company to conduct marine hydrodynamic research for oil tankers and offshore structures. Since joining DTNSRDC in 1969 he has actively conducted and directed hydrodynamic research to advance naval ship design technology and improve ship performance. Active in national and international symposia on ship hydrodynamic research he is recognized for contributions to the ship research community. For the past six years he has been a member of the Performance Committee of the ITTC and currently serves as secretary of the committee. He is a member of SNAME and the Society of Naval Architects of Japan. William G. Day Jr:. has been employed as a naval architect at the David Taylor Naval Ship R&D Center since receiving a B.E.S. degree from the Johns Hopkins University in 1966. He obtained an M.S. E. degree from George Washington University in 1971. As Head Design Evaluation Branch of the Ship Performance Department he is responsible for model experiments to evaluate the hydrodynamic performance of ships and propulsors. He is a member of ASNE and SNAME. In-Young Koh:received his B.S. and M.S. degrees in electrical engineering from Lowell University in 1969 and 1971 respectively and his Ph.D. in applied mechanics from Rensselaer Polytechnic Institute in 1976. Dr. Koh joined DTNSRDC as an electronic engineer specializing in the application of advanced instrumentation and computer techniques to ship research and design. He is currently engaged in research and development of active control systems for naval ship applications. Dr. Koh is a member of ASNE SNAME and IEEE. David Andrew Walden:is

A ship design methodology is presented for developing hull forms that attain improved performance in both seakeeping and resistance. Contrary to traditional practice, the methodology starts with developing a seakeeping-optimized hull form without making concessions to other performance considerations, such as resistance. The seakeeping-optimized hull is then modified to improve other performance characteristics without degrading the seakeeping. Presented is a point-design example produced by this methodology. Merits of the methodology and the point design are assessed on the basis of theoretical calculations and model experiments. This methodology is an integral part of the Hull Form Design System (HFDS) being developed for computer-supported naval ship design. The modularized character of HFDS and its application to hull form development are discussed.

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DESIGN OF BUTTERWORTH AND TSCHEBYSCHEV DIGITAL-FILTERS

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INTERNATIONAL JOURNAL OF electrical engineering EDUCATION 1983年第1期20卷 59-70页

作者： THYAGARAJAN, KS BRISENO, AE VALENCIA, AA Department of Electrical & Computer Engineering San Diego State University U.S.A. Department of Applied Physics CICESE Ensenada Mexico

This paper describes the procedure for the design of digital Butterworth and Chebyshev filters in the frequency domain. A sequence of steps is given to compute the coefficients of the digital filter that meets the desired specifications. The technique of applying the frequency transformation in the digital domain to the design of other filters such as highpass, bandpass and bandstop is also included.

关键词： ELECTRIC FILTERS, DIGITAL

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Optical switching in organometallic films

Optical switching in organometallic films

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Conference on Lasers and Electro-Optics, CLEO 1983

作者： Benson, R.C. Hoffman, R.G. Potember, R.S. Poehler, T.0. Bqurkoff, E. Applied Physics Laboratory Johns Hopkins University LaurelMD20707 United States Department of Electrical Engineering and Computer Science Johns Hopkins University BaltimoreMD21218 United States

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An Investigation of Adjustment Gain Design in Stationary and Nonstationary LMS Adaptive Algorithms

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IFAC Proceedings Volumes 1982年第4期15卷 1335-1340页

作者： T.C. Hsia S. Sugimoto Department of Electrical and Computer Engineering University of California Davis California 95616 USA Department of Applied Physics Osaka University Osaka japan

A statistical analysis is presented for the random adjustment gain β k of the NLMS adaptive algorithm based on Gaussian iid assumption of the input vector. It is found that the mode of β k closely approximates the constant adjustment gain μ of the UIS algorithm. Thus the mode of β k can serve as a "rule of thumb" for the design of μ. This result is particularly useful for designing nonstationary LMS algorithms.

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