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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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磁扰日向阳面对流电场转向区位置的晨昏不对称性(STARE、TRIAD、AE-C观测综合分析)

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空间科学学报 1986年第1期 9-18页

作者：资民筠,E.Nielsen,W.B.Hanson,T.A.Potemra 北京大学地球物理系 Max-planck-Institut Center for Space Science Physics program Univ.of Texas at Dallas Applied Physics Laboratory Johns Hopkins Univ. Laurel MD für Aeronomie Lindau Germany

本文通过STARE观测的晨不连续性及其与TRIAD观测的场向电流分界区、AE-C卫星观测的电场转向区位置的比较,提出了在高扰日向阳面对流电场转向区位置存在着晨不对称性——晨半面所处纬度低于昏半面.该现象间接说明向阳面磁层边界层也存在... 详细信息

本文通过STARE观测的晨不连续性及其与TRIAD观测的场向电流分界区、AE-C卫星观测的电场转向区位置的比较,提出了在高扰日向阳面对流电场转向区位置存在着晨不对称性——晨半面所处纬度低于昏半面.该现象间接说明向阳面磁层边界层也存在某种不对称性.并在观测基础上对可造成该不对称性的物理因子进行了探讨,认为行星际磁场螺线结构对重连区位置的影响及其产生的激波结构的晨昏不对称性很可能与本文中讨论的现象有一定联系.

关键词：场向电流磁扰日对流电场转向区磁层 TRIAD STARE 不对称性

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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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KINETIC-ANALYSIS OF NUCLEAR AND COULOMB SCATTERING IN HIGH-TEMPERATURE TANDEM MIRROR PLASMAS

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NUCLEAR FUSION 1984年第10期24卷 1335-1346页

作者： KANTROWITZ, FD CONN, RW Present address: Electron Dynamics Division Hughes Aircraft Company P.O. Box 2999 Torrance CA 90509 USA Fusion Engineering and Physics Program School of Engineering and Applied Science University of California Los Angeles California United States of America

A two-dimensional kinetic theory analysis is used to determine distribution functions in high-temperature mirror plasmas in which both Coulomb and nuclear elastic scattering are important. The discrete nature of nuclear scattering and the continuous nature of Coulomb scattering are incorporated. The distribution functions are used to obtain the energy deposition and energy and particle loss rates for fusion reaction products such as alpha particles and protons in the central-cell plasma of a tandem mirror. The confinement time for neutral-beam-injected ions in the plug of a tandem mirror or in a single-cell mirror is also determined. Large-angle scattering losses are found to depend more strongly on mirror ratio than losses due to small-angle scattering, although including the motion of background ions reduces the effects of nuclear scattering. For d-t reactor parameters, the effects of nuclear scattering are not significant. For d-d reactors, however, the confinement time for 700 keV plug neutral beams is found to decrease by 20%.

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HUMAN-FACTORS CONSIDERATIONS applied TO OPERATIONS OF THE FFG-8 AND LAMPS MK III

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NAVAL ENGINEERS JOURNAL 1984年第3期96卷 191-199页

作者： BAITIS, AE APPLEBEE, TR MCNAMARA, TM A. Erich Baitis: a native of Germany came to the David W. Taylor Naval Ship R&D Center in 1957 as a cooperative student/trainee and received his B.S. degree in physics from Virginia Polytechnic Institute. As a 32-year-old naval architect in 1971 he received both the Vietnam Honor Service Medal and the Navy's Meritorious Civilian Service Award for his eight months as liaison with the Vietnamese Navy's ferro-cement program. As head of the Seakeeping and Stabilization Group of the Surface Ship Dynamics Branch his work has led to the development of a new standard Ship Motion Computer Program and the application of ship motions to ship habitability operability and survivability problems. A major area of this work has been the ship-aircraft interface which is particularly sensitive to ship motions wind and other environmental factors. He is a member of the American Society of Naval Engineers and was awarded the Solberg Award for 1982 “in recognition of significant engineering research and development contributions in the area of improved helicopter operations from a ship in a seaway.” Terrence A. Applebee:is currently a naval architect at the David W. Taylor Naval Ship R&D Center in the Surface Ship Dynamics Branch. he came to the Center after earning a B.S. degree in ocean engineering from Florida Institute of Technology in 1973. Since that time he has worked in the areas of seakeeping performance evaluation ship-helicopter interfacing and human factor considerations. He is a member of the American Society of Naval Engineers and the Society of Naval Architects and Marine Engineers. Thomas M. McNamara:is an employee of the John Hopkins University Applied Physics Laboratory in the ocean data acquisition program. From 1979 to 1983 he worked at David W. Taylor Naval Ship R&D Center in the Surface Ship Dynamics Branch. His expertise has focused on the development of computer models for human factor evaluations as well as motion stabilization systems. He has participated in the development of advanced stabilizat

The FFG 7/LAMPS MK III Operator Guidance Manual (OGM) was developed for all FFG-7 class frigates which are not fin stabilized or are operating with the fins off. The OGM was developed to assis the ship operators of the FFG-7 class in choosing ship speed and heading combinations which will minimize ship motion-related problems during various phases of the LAMPS deployment. Crew safety and performance were major concerns in the development of the OGM. This paper reviews the effect of human factors on ship operations during helicopter recovery, maintenance, and transit to and from the hangar.

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RATIONALE FOR AN ADA SOFTWARE ENGINEERING ENVIRONMENT FOR NAVY MISSION CRITICAL APPLICATIONS

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NAVAL ENGINEERS JOURNAL 1984年第4期96卷 133-145页

作者： PAIGE, KK CONVERSE, RA USN LCdr. Kathleen K. Paige USN:graduated with a BA from the University of New Hampshire in 1970. She received her commission from Officer Candidate School in April 1971 and performed her first tour of duty with VFP-63 NAS Miramar. LCdr. Paige then received her MS from the Naval Post Graduate School in June 1976 and returned to San Diego to serve as Head Support Software Division at the Fleet Combat Direction System Support Activity. In May 1981 she reported to NA VSEA (PMS-408) where she served initially as Chairman of the NAVMAT Software Engineering Environment Working Group. She has been assigned as Deputy AN/UYK-43 Acquisition Manager since October 1981. LCdr. Paige was designated a fully qualified Engineering Duty Officer in December 1983. Robert A. Converse:is presently the Acquisition Manager for the Ada Language System/Navy (ALS/N) for the Naval Sea Systems Command Tactical Embedded Computer Resources Project. As such he is responsible for the definition and development of the ALS/N to be provided as a Navy standard computer programming system for Navy mission critical applications. Mr. Converse received a Bachelor of Science degree in Physics from Wheaton College Wheaton II. He spent fourteen years with the Naval Underwater Systems Center Newport Rhode Island during which time he designed and developed the Fortran compiler for the Navy Standard AN/UYK-7 computer. Also during that period he received a Master of Science degree in Computer Science from the University of Rhode Island. His thesis for that degree was entitled “Optimization Techniques for the NUSC Fortran Cross-Compiler”. Mr. Converse started his involvement with the Ada program in 1975 with the initial “Strawman” requirements review. Subsequently he was named as the Navy Ada Distinguished Reviewer and was intimately involved in the selection and refinement of the Ada language as it evolved to become ANSI/MIL-STD-1815A.

The U.S. Navy introduced the use of digital computers in mission critical applications over a quarter of a century ago. Today, virtually every system in the current and planned Navy inventory makes extensive use of computer technology. computers embedded in mission critical Navy systems are integral to our strategic and tactical defense capabilities. Thus, the military power of the U.S. Navy is inextricably tied to the use of programmable digital computers. The computer program is the essential element that embodies the system “intelligence”. In addition, it provides the flexibility to respond to changing threats and requirements. However, this very flexibility and capability poses a host of difficulties hindering full realization of the advantages. This paper describes the lessons learned about computer program development over the past twenty five years and discusses a software engineering process that addresses these lessons. It then describes how Ada and its related Ada programming Support and Run-Time Environments foster this software engineering process to improve computer program productivity and achieve greater system reliability and adaptibility. Finally, the paper discusses how the use of Ada and its environments can enhance the interoperability and transferability of computer programs among Navy projects and significantly reduce overall life cycle costs for Navy mission critical computer programs.

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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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ION TIME-OF-FLIGHT SPECTROSCOPY: KRYPTON CHARGE STATE SPECTRA AS A FUNCTION OF PHOTON EXCITATION ENERGY NEAR THE K EDGE.

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Nuclear instruments and methods in physics research 1983年第1-3期208卷 815-818页

作者： Hastings, J.B. Kostroun, V.O. National Synchrotron Light Source Brookhaven National Laboratory Upton New York 11973 USA Nuclear Science and Engineering Program and School of Applied and Engineering Physics Cornell University Ithaca New York 14853 USA

In this experiment, the charge state distribution resulting from atomic rearrangement following the creation of the inner shell vacancies in krypton atoms has been recorded. Intense, highly collimated, monochromatic and tunable X-ray radiation available at the CHESS synchrotron radiation facility at Cornell was used to photionize krypton atoms in a gas jet target, and a time-of-flight spectrometer was used to record the ions in different charge states formed after photoionization. Charge state spectra were recorded below, at the 'peak' in the K edge and above the edge. Below the edge, charge states plus 4 to plus 7 were observed with appreciable intensity, while at, and above the edge, the charge states ranged from plus 4 to plus 10.

关键词： Spectroscopy

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DEEP WATER PORT - FIRE & EXPLOSION HAZARDS ASSESSMENT.

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Plant/operations progress 1983年第2期2卷 89-98页

作者： Bergmann, Ernest P. Riegel III, John P. Southwest Research Institute San Antonio Texas 78284 John P. Riegel joined the Southwest Research Institute Department of Energetic Systems during his senior year at UTSA and assumed a permanent position upon graduation. During this time he has been involve in several areas of ballistics and explosives research. Prior to joining the Institute he worked on several NASA grants at UTSA. This work included the writing of computer programs to facilitate the design and construction of a fast ion mass spectrometer (FIMS) for flight on The University of Texas at Dallas cleft sounding rocket and for future satellite use. He also developed a program to determine the trajectory of TADs (throwaway detectors) to be launched from the space shuttle and he worked on the selection and reduction of data for the Atmospheric Explorer Satellites. He holds a B.S. in Applied Physics from the University of Texas at San Antonio and has done graduate study in Business Administration.

The objective of the program reported in this paper was to assess the explosion and fire hazard associated with the crude-oil offloading facility proposed for the Deep Water Port, Galveston, Texas. Explosion damage estimates were made for two conditions;the ″worst case,″ which involved 36 percent of the tanks of the largest tanker. Fire effects were investigated on the basis of six fire scenarios. Fire-control techniques were postulated and equipment characteristics and quantities were defined. The inert-gas system (IGS) was evaluated in terms of operational characteristics, reliability, failure modes and effects, and controls.

关键词： PORTS AND HARBORS

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RUDDER ROLL STABILIZATION FOR COAST GUARD CUTTERS AND FRIGATES

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NAVAL ENGINEERS JOURNAL 1983年第3期95卷 267-282页

作者： BAITIS, E WOOLAVER, DA BECK, TA Dr. Erich Baitis: a native of Germany came to the David W. Taylor Naval Ship Research and Development Center in 1957 as a co-operative student/trainee and received his Bachelor of Science Degree in Physics from Virginia Polytechnic Institute. As a 32-year-old naval architect in 1971 he received both the VietnamHonorServiceMedaland the Navy'sMeritoriousCivilianServiceAwardfor his eight months as liaison with the Vietnamese NAVVS ferro-cement ship program. As head of the Seakeeping and Stabilization Group of the Surface Ship Dynamics Branch his work has led to the development of a new standard Ship Motion Computer Program and the application of ship motions to ship habitability operability and survivability problems. A major area of this work has been the ship/aircraft interface which is particularly sensitive to ship motions wind and other environmental factors. Mr. Dennis A. Woolaver:has been employed as a Naval Architect at the David W. Taylor Naval Ship Research and Development Center since 1965 where his work has resulted in numerous patents. He received his Bachelor of Science Degree in Electrical Engineering from George Washington University where he also completed graduate work in Communication Theory. Additional fields of study include Computer Science and Personnel Management. Current efforts are directed toward surface ship motion mitigation data acquisition and statistical analysis. He is a member of the Society of Naval Architects and Marine Engineers. Lt. Tom A. Beck USCG: joined the UnitedStatesCoastGuardin 1966 where he trained as an Electronics Technician. He received a Bachelor of Science Degree in Electrical Engineering from Columbia University in 1978. From 1978 to 1979 he was an Electronics Project Officer at the CoastGuardElectronics Laboratory in Alexandria Virginia. Since 1980 he has been a Research and Development Project Officer in the Sensor Technology Branch of the CoastGuardsOffice of Research and Development. Lt. Beck is a member of the Institute of Electronic and Elect

The potential use of rudders as anti-roll devices has long been recognized. However, the possible interference of this secondary function of the rudder with its primary role as the steering mechanism has prevented, for many years, the development of practical rudder roll stabilizers. The practical feasibility of rudder roll stabilization has, however, in recent years been demonstrated by two systems designed and developed for operational evaluation aboard two different U.S. C oast G uard Cutters, i.e., Jarvis and Mellon of the 3,000-ton, 378-foot HAMILTON Class. The authors describe the major components of the rudder roll stabilization (RRS) system, along with the design goals and methodology as applied to these first two prototypes. In addition, a brief history of the hardware development is provided in order to show some of the lessons learned. The near flawless performance of the prototypes over the past four years of operational use in the North Pacific is documented. Results from various sea trials and reports of the ship operators are cited and discussed. The paper concludes with a discussion of the costs and benefits of roll stabilization achieved using both a modern anti-roll fin system, as well as two different performance level RRS systems. The benefits of roll stabilization are demonstrated by the relative expansion in the operational envelopes of the USS OLIVER HAZARD PERRY (FFG-7) Class. The varying levels of roll stabilization suggest that the merits of fins and RRS systems are strongly dependent on mission requirements and the environment. The demonstrated performance of the reliable RRS system offers the naval ship acquisition manager a good economical stabilization system.

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