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PArALLEL ANd dISTrIBUTEd TLM COMPUTATION WITH SIGNAL-PrOCESSING FOr ELECTrOMAGNETIC-FIELd MOdELING

INTErNATIONAL JOUrNAL OF NUMErICAL MOdELLING-ELECTrONIC NETWOrKS dEVICES ANd FIELdS 1995年第3-4期8卷 169-185页

作者： SO, PPM ESWArAPPA, C HOEFEr, WJr NSERC/MPR Teltech Research Chair in RF Engineering Department of Electrical and Computer Engineering University of Victoria Victoria British Columbia V8W 3P6 Canada Poman So received his B.Sc. degree in computer science and physics from the University of Toronto Toronto Onatario Canada in 1985. He obtained his B.A. Sc. and M.A.Sc. degrees in electrical engineering (summa cum laude) from the University of Ottawa Ottawa Ontario Canada in 1987 and 1989 respectively. Mr So was a research engineer in the University of Ottawa from January 1989 to October 1991 his research interests included CAD techniques of microwave circuits and numerical methods for electromagnetic wave modelling. He specialized in the development of electromagnetic engineering CAD software and successfully implemented a number of electromagnetic wave simulators based on the two-dimensional and three-dimensional transmission-line matrix methods. From August 1990 to February 1991 he accompanied Professor W. J. R. Hoefer to Rome Italy and Sophia Antiopolas France. During that time he implemented a parallel version of the 3D-TLM simulator for the CM-2 Connection Machine using C-Star and X Windows Library. He is a research engineer and a Ph.D. student at the University of Victoria Victoria British Columbia Canada. He ported the 2D- and 3D-TLM simulators to DECmpp 1200 massively parallel computer using MPL C and C++. He also combined OSA90/hope a commercially available microwave CAD program with a 2D-TLM simulation module for geometry optimization using the Datapipe technique of OSA90/hope. Recently he has developed a distributed client-server computing technique for the TLM method this technique could accelerate the TLM simulation by more than an order of magnitude. Channabasappa Eswarappa received the M.Tech. degree in electrical engineering from the Indian Institute of Technology Kanpur India in 1983 and Ph. D. degree from the University of Ottawa Canada in 1990. He worked as an Assistant Executive Engineer and later as

This paper describes the implementation of transmission-line matrix (TLM) method algorithms on a massively parallel computer (dECmpp 12000), the technique of distributed computing in the UNIX environment, and the combination of TLM analysis with Prony's method as well as with autoregressive moving average (ArMA) digital signal processing for electromagnetic field modelling. By combining these advanced computation techniques, typical electromagnetic field modelling of microwave structures by TLM analysis can be accelerated by a few orders of magnitude.

关键词： Mathematical models

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ArCHITECTUrE ANd NETWOrKING ISSUES IN SATELLITE SYSTEMS FOr PErSONAL COMMUNICATIONS

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INTErNATIONAL JOUrNAL OF SATELLITE COMMUNICATIONS 1994年第1期12卷 33-44页

作者： ANANASSO, F CArOSI, M Received the Electronics and Electrical Communications Degree from the University of Rome in 1973 after which he joined Selenia S.p.A (Rome) as a microwave designer in the Development Laboratory. He was involved in several military and civilian projects concerning microwave subsystems for Radar Avionics and Satellite Communications equipment. In 1981 he joined Telespazio S.p.A. (Rome) as Section Chief in the Space and Advanced Programs Division with responsibilities related to satellite payload and digital transmission channel design. In 1987 he was appointed Associate Professor of Digital Signal Processing at the University of Rome Tor Vergata Electronics Engineering Department. In 1990 he again joined Telespazio where he is now Director of the Advanced Studies and Experimentations Division. He has performed a number of studies for National and International Organizations including ESA EUTELSAT INMARSAT and INTELSAT is author of a Radio Systems book a Chapter (‘Digital transmission channel’) of the ‘Satellite Communication System Design’ book by Plenum Publishing (1993) and over 80 technical papers on communication systems and technology. Received the Electronics and Electrical Communications Degree from the University ‘La Sapienza’ of Rome Italy in 1987. From 1987 to 1990 he worked as a Research Engineer in the INFOCOM department of the University ‘La Sapienza’ of Rome carrying out research on design and performance evaluation of multiple access protocols particularly in the metropolitan area network and in the satellite fields. Since 1990 he has been working in the System Studies and Payload group of Telespazio S.p.A. Rome Italy. He is currently involved in projects sponsored by the European Space Agency and by INMARSAT for communications systems via satellite for mobiles both at study and R&D level. Mr Carosi is a member of the IEEE Communication Society.

The paper expands on some specific aspects of personal communications via satellite, often-although not necessarily-envisaging extensive use of 'small' satellites, using orbits not necessarily coinciding with the geostationary one (36,000 km), but rather at 1000-11,000 km altitude. One key point to be borne in mind is the issue of internetworking between satellite and terrestrial systems. Network integration should be carefully implemented in order to comply with ITU future public land mobile telecommunication systems (FPLMTS) requirements, also accepted in the European Telecommunication Standards Institute (ETSI) universal mobile telecommunication systems (UMTS). In addition to some insight into the technology of small satellites and associated orbits, architectures and networking aspects of most relevant systems providing personal communication services (PCS) are addressed in some detail, and potential applications highlighted. Frequency spectrum allocation is addressed in the light of the 1992 World Administrative radio Conference (WArC-92), taking into account also multiple access problems and regulatory issues such as Federal Communications Commission (FCC) licensing and spectrum sharing debates. Some remarks on critical technologies and cost conclude the paper.

关键词： PErSONAL COMMUNICATIONS SMALL SATELLITES NETWOrKING FrEQUENCY SPECTrUM

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PErFOrMANCE OF A PrIOrITIZEd ON-BOArd BASEBANd SWITCH FOr A MULTISErVICE MULTIBEAM SATELLITE

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INTErNATIONAL JOUrNAL OF SATELLITE COMMUNICATIONS 1994年第3期12卷 283-297页

作者： BOHM, S ELHAKEEM, AK HACHICHA, M Department of Electrical and Computer Engineering Concordia University 1455 De Maisonneuve Blvd. West Montreal H3A 1M8 Canada Was born in Montreal Canada on 14 September 1966. He received the B. Eng. degree in electrical engineering from Concordia University Montreal Canada in 1989. He is at present completing the M.A.Sc. degree in electrical engineering at Concordia University. (S'75–S'79–M'79–SM'86) received the Ph.D. degree from Southern Methodist University Dallas TX in 1979. He spent the next two years working as a Visiting Professor in Egypt after which he moved to Ottawa Canada in 1982. He assumed teaching and research positions in Carleton and Manitoba Univerities and later moved to Concordia University Montreal Canada in 1983 where he is now a Professor in the Electrical and Computer Engineering Department. He has published numerous papers in IEEE and international journals in the areas of spread spectrum and networking. He is a well-known expert in these areas and serves as a consultant to many companies. His current research interests include wide-band metropolitan networks switching architectures and performance of on-board multibeam satellites acquisitionless CDMA networks code distribution and orthogonalization of CDMA signals responsive congestion control for ATM-based networks ARQ techniques and investigation of the novel SUGAR CDMA systems in fading channels. Dr. Elhakeem is a Senior Member of the Canadian Electrical Engineering Society and Armed Forces Association. He has chaired numerous technical sessions in IEEE Conferences was the Technical Program Chairman for IEEE Montech 1986 Montreal Canada. Dr. Elhakeem is the key guest editor of theIEEE Journal of Selected Areas in Communicationsfor the May June issues 1993 covering CDMA networks. Advanced Technology & Networks VISTAR Telecommunications Inc. Ottawa Ontario K1G 3J4 Canada An Associate Director of Advanced Technology & Networks Group VISTAR Telecommunications Inc. Ottawa Canada. He is also an Adjunct Pr

In this paper, we study the performance of a prioritized on-board baseband switch in conjunction with a multibeam satellite handling integrated services. The services considered for the analysis include voice, video, file transfer and interactive data. The prioritized switch uses both input and output buffering, switch speed-up as well as a two-phase head-of-line resolution algorithm, in order to reduce the buffer loss while maintaining acceptable user delays. The minimum required buffer capacity and switch speed-up for each service in a prioritized environment are found under uniform traffic conditions. It is shown that under uniform traffic conditions, only minimal buffering and switch speed-up are needed even for the lowest priority users. The performance dependence on the switch size is also substantially reduced with head of line resolution and buffering even in a prioritized environment.

关键词： SWITCH ON-BOArd BASEBANd MULTIBEAM PrIOrITIZEd HEAd-OF-LINE UNIFOrM LOAd SPEEd-UP

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ArTIFICIAL NEUrAL NETWOrKS ANd THEIr APPLICATION TO WEAPONS

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NAVAL ENGINEErS JOUrNAL 1991年第3期103卷 46-59页

作者： WEBSTEr, WP The Author The Author is the technology manager for the Intercept Weapons Department at the Naval Weapons Center China Lake Calif. Dr. Webster received his B.S. M.S. and Ph.D. degrees in electrical engineering at the University of Arizona Tucson Arizona in 1964 1966 and 1971 respectively. While at the University of Arizona his studies focused on electromagnetic field propagation and scattering and laser radar system design. Since graduation he has worked at the Naval Weapons Center in a variety of technology areas including laser radar system design infrared system design proximity fuze system design hybrid and monolithic microelectronic circuit design and fabrication technology airborne fire control sensor technology and anti-air and anti-surface missile guidance and control technology. Currently he is responsible for identifying selecting and directing the development of advanced guidance sensor signal processing and aerodynamic control system technologies for application to U.S. Navy tactical electro-optical and radio frequency air intercept missiles. Dr. Webster is a member of IEEE Sigma Xi and Tau Beta Pi.

Complex processing algorithms associated with requirements for real-time target detection, acquisition and recognition have far outdistanced our ability to package the necessary processing power into real-time weapon-sized hardware. Weapon developers need new, radically different, approaches to solve these difficult weapon signal processing problems. Artificial neural networks (ANN) is one of the new, radically different, signal processing approaches that is currently receiving much attention for weapon applications. The human brain is a powerful image and pattern recognition processor whose basic processing element is the neuron. Synapses are the weighted interconnections between neurons that permit learning and communication between the neurons. Artificial neural network technology attempts to mathematically and/or electrically model neurons and synapses and then interconnect these models in architectures suitable for signal processing tasks. ANN technology is particularly applicable to pattern recognition, speech recognition, machine vision, robotics, and optimization signal processing tasks. Specific military applications include missile seekers, missile fuzing, sonar target discrimination, automatic target recognition, and autopilots. Two unique characteristics of ANN processors are that they are non-linear processors and that they are trained, not programmed, to accomplish processing tasks in a manner analogous to the way the human brain learns. Learning is achieved by modifying the synaptic weights of each artificial neuron until the final desired system processing response is achieved. Several years ago the Naval Weapons Center (NavWpnCen) identified ANN technology as a high risk-high payoff approach to missile signal processing requirements and initiated several research and development efforts in this area. One result of this work is the new 80170NW ANN analog VLSI chip produced by Intel Inc. Another is the current Missileborne Integrated Neural Network de

关键词： Neural Networks

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CUrrENT LIMITING PrOTECTOr FOr LOW-VOLTAGE, HIGH-CUrrENT APPLICATIONS

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NAVAL ENGINEErS JOUrNAL 1989年第3期101卷 267-273页

作者： EMErY, FT WU, JL Dr. Franklin T. Emery:is a senior engineer in the Electromechanical Systems Department at the Westinghouse R&D Center Pittsburgh Pa. Dr. Emery received his B.S. (1974) M.S. (1977) and Ph.D. (1983) degrees in electrical engineering from the University of Pittsburgh Pittsburgh Pa. His primary work is in applied research on electrical systems associated with large power systems both for Navy ship applications and for the commercial power industry. He is presently involved in the development of the electronics for a high current high speed interrupter for use in the protection of power distribution systems on board Navy surface ships. His prior experience is in fiber optic technology design and application for both SDI and Navy applications. He is a Senior Member of IEEE and is a professional registered engineer in Pennsylvania and Florida. Dr. Jiing L. Wu:is a senior research scientist in the Electromechanical Systems Department at the Westinghouse R&D Center Pittsburgh Pa. Dr. Wu received his B.S. degree in mechanical engineering from Taiwan Cheag Kung University Taiwan in 1965 M.S. in mechanical engineering from the University of Wisconsin Madison in 1969 and Ph.D. in engineering science from the State University of New York Buffalo New York in 1974. He has participated in research and development work in pulsed power switching devices for electromagnetic launchers circuit breakers for commercial and naval electrical systems and fault current limiting devices. He is presently the principal investigator and project manager of a team developing the current limiting protector for the Naval Sea Systems Command.

A pyrotechnic current limiting interrupter (CLI) has been developed for use in high current, 60-Hz, 480-volt, 3-phase electrical bus circuits. The interrupter design combines a high continuous current (4800 A rms) rating with a high current (210 kA rms sym.) interruption capability. Its electrical power loss is low and its mechanical construction uses no complex moving mechanisms. The CLI is used with a current sensor, electronic logic, and energy storage circuitry. The current sensor continuously monitors the current through the CLI and provides input to logic circuits which analyze and determine the validity of the fault condition. Both the fault current magnitude and rate of current increase are used in combination to make the decision when to activate the CLI. Using stored electrical energy, a detonator is activated causing an explosive cord to generate shock waves sufficient to cut the current carrying conductors. detection and initiation of the interruption process occurs within 1/4 cycle for a symmetrical fault and within 1/2 cycle for an asymmetrical fault. The first peak in the fault current is limited to the first half cycle.

关键词： Electric circuit Breakers

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recent progress on submicron electron beam lithography

Recent progress on submicron electron beam lithography

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Electron-Beam, X-ray, and Ion-Beam Technology for Submicrometer Lithographies V 1986

作者： Takigawa, Tadahiro Shimazaki, Kuniya Kusui, Naoki VLSI Research Center Toshiba R and D Center Toshiba Corporation 1 Komukai Toshibacho Saiwai-ku Kawasaki-city210 Japan Mask Engineering Section Integrated Circuit Advanced Process Engineering Deaprtment Toshiba Corporation 1 Komukai Toshibacho Saiwai-ku Kawasaki-city210 Japan Electron Machine Department Advanced Machine and Equipment Division Toshiba Machine Co. Ltd. 2068-3 Ooka Numazu-city Shizuoka-ken410 Japan

In order to fabricate submicron pattern, total electron beam (EB) lithography system has been developed. Upper submicron pattern will be realized by optical lithography, which requires reticle with high accuracy. An EB writing system, EBM-130/40, has the performance of drawing capability of 4 M bit drAM reticle pattern in about 40 minutes. The EB system incorporated with peripheral technologies including data compaction conversion software, reticle inspection system, APC-130r, and EBr-9 resist process can produce advanced reticles of number of about 600 per month. For lower submicron pattern formation, next generation lithography system is required. The EBM-130V is the variable shaped EB system with high acceleration voltage of 50 kV and high dosage of 50 μC/cm2 for direct writing and X-ray mask fabrication for development of the high bit density VLSI pattern. This system makes possible EB/optical combined lithography. Its metrology function allows it to measure X-ray mask distortion. © 1986 SPIE. All rights reserved.

关键词： Electron beams

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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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THE CONFOrM PrOGrAM - AN UPdATE

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NAVAL ENGINEErS JOUrNAL 1984年第3期96卷 94-110页

作者： SPAULdING, KB The AuthorKenneth B. Spaulding Jr.received his B.S. degree in naval architecture from Webb Institute in 1954 and M.S. degree in R&D management from American University in 1974. After two years as a Navy fiberglass shipbuilding inspector at Defoe Shipbuilding he came to the Bureau of Ships where for fourteen years he worked in the boat design group progressing through head of the Boat Contract Design and Boat Preliminary Design Groups to headquarters coordinator for the Norfolk Boat Design Department. This was followed by a year on the Trident project two years as Deputy Ship Design Manager for the FFG 7 and two years in development of design management procedures. From 1975 to 1980 he was LCAC Design Manager and head of the Hydrofoil Design Unit. This assignment included Naval Ship Engineering Center technical management of the Advanced Naval Vehicles Concepts Evaluation (ANVCE) Program. Since 1980 he has been head of the Advanced Design (hydrofoil ACV SES SWATH) Section (SEA 50151) and Technical Director for the CONFORM Program. Mr. Spaulding is a member of ASNE SNAME ASE and the U.S. Hovercraft Society.

This paper provides a progress report on the Naval Sea Systems Command (NAVSEA) Surface Ship Continuing Concept Formulation (CONFOrM) program, first introduced to the Society at ASNE day, 1981, by Commander Michael r. Terry. Since that time the program has produced many designs, achieved significant visibility and influence, and evolved in character. designs and problem areas are summarized and the future potential of the program discussed.

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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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MACHINErY ArrANGEMENT design - A PErSPECTIVE

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NAVAL ENGINEErS JOUrNAL 1981年第3期93卷 133-141页

作者： rESNEr, ME KLOMPArENS, SH LYNCH, JP Mr. Michael E. Resner:received an Engineering Degree from Texas A&M University in 1966 and has done graduate work in management at American University. He is Director Machinery Arrangements/Control Systems and Industrial Facilities Division (SEA 525) at the Naval Sea Systems Command. His previous positions have included Program Manager Solar Total Energy Program at the Department of Energy and Branch Chief Machinery Control Systems Branch at the Naval Ship Engineering Center. Mr. Stephen H. Klomparens:is a Naval Architect at Designers & Planners Inc. and is engaged in development of computer aids for ship design. He received his B.S.E. degree in Naval Architecture and Marine Engineering from the University of Michigan in 1973 and his M.S. degree in Computer Science from the Johns Hopkins University. Mr. Kolmparens began his professional career at Hydronautics Inc. in 1974 where he was involved in the use of marine laboratory facilities for test and development of conventional and advanced marine craft. Since 1977 he has been involved with naval and commercial ship design and with development of computer-aided ship design tools. Mr. John P. Lynch:is a Principal Marine Engineer with Hydronautics Inc. He was previously employed in the auxiliary machinery and computer-aided design divisions of the David W. Taylor Naval Ship R&D Center the machinery design division of the New York Naval Shipyard and the machinery arrangement code of the Bureau of Ships. His active naval service was as a ship superintendent in the production department of the Long Beach Naval Shipyard. Mr. Lynch received his B. S. degree in Marine Engineering from the New York State Maritime College and his M.S. degree in Mechanical Engineering from Columbia University. He is a licensed Professional Engineer in the State of New York and a member of ASNE.

The machinery arrangement design process has remained relatively unchanged over the years. recently, external demands have been placed on both the product and the producers that call for changes to this process. This paper cites these external demands and traces the evolution of the process changes from the rule-of-thumb machinery box sizing routines up to the current automated procedures. The machinery arrangement design practice is presented, and existing analytic and graphics aids are discussed. The user requirements for improved design aids are presented, with implementation guidelines and hardware/software alternatives.

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