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Transient analysis of an advanced static Var compensator using quad-series voltage-source PAM inverters

ELECTRICAL engineering IN JAPAN 1996年第2期117卷 93-106页

作者： Tominaga, S Fujita, H Akagi, H Okayama University [?]Received his Master's degree in Electrical and Electronic Engineering in 1995 from the Engineering Research Division of the Graduate School Okayama University. He is currently in the doctoral program in system science at the Natural Sciences Research Division of the Graduate School of the same university. He is engaged in research on reactive power compensators.

This paper deals with an advanced static Var compensator (ASVC) using quad-series voltage-source PAM inverters. The ASVC consists of four three-phase voltage-source inverters with a common de capacitor and four three-phase transformers, each primary winding of which is connected in series with each other. Each inverter outputs a square-wave voltage, while the synthesized output voltage of the ASVC has a 24-step wave shape. This results not only in a great reduction of harmonic currents and de voltage ripples but also in fewer switching and snubbing losses. In this paper, transient analysis is performed with the focus on the response of reactive power and the resonance between the de capacitor and ac reactors. Experimental results obtained from a small-rated laboratory model of 10 kVA are also shown to verify analytical results based on the p-q transformation. The analytical results help in the design of system parameters such as the capacity of the de capacitor and feedback gains.

关键词： reactive power compensator voltage-source inverter PAM higher harmonics power system stabilization

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New microscope for measuring the distribution of nonlinear dielectric properties

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ELECTRONICS AND COMMUNICATIONS IN JAPAN PART II-ELECTRONICS 1996年第6期79卷 68-75页

作者： Cho, Y Kirihara, A Saeki, T Department of Electrical and Electronic Engineering Faculty of Engineering Yamaguchi University Ube Japan 755 Received his B.E. M.S. and Dr. of Eng. degrees from Tohoku University in 1980 1982 and 1986 respectively. He joined the University as a Research Associate in the Research Institute of Electrical Communication in 1985. He joined Yamaguchi University in 1990 as an Associate Professor in the Electrical and Electronic Engineering Department. He has been involved in research on nonlinear phenomenon of piezoelectric materials and their application. Received his B.E. degree in Electrical and Electronic Engineering from Yamaguchi University in 1995. He is working at present for the University as a technical official. He has been involved in research on the telecommunication electronic circuits and the application of the piezoelectric materials. Received his B.E. degree in Electrical and Electronic Engineering from Yamaguchi University in 1995 and has been involved in research and development of the scanning nonlinear dielectric microscope system. He is at present in the Master's program in the Electrical Engineering Department of Kyushu University.

This paper describes a new technique for imaging the distribution of nonlinear dielectric constants of ferroelectric materials. This technique is based on the principle that the nonlinear (third-order) dielectric constants (third-rank tensor) are very sensitive to the state of the spontaneous polarization and the quality of the crystallization of materials, while the linear (second-order) dielectric constants (second-rank tensor) are insensitive to them. Applying this principle, a new microscope for measuring the distribution of nonlinear dielectric properties is developed. This new microscope is used to observe the distribution of the polarization of ferroelectric materials such as lead zirconate titanate (PZT) ceramic and piezoelectric polymer.

关键词： ferroelectric materials nonlinear dielectric constant microscope piezoelectric materials

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Soliton system evaluations using fibers with dispersion and loss fluctuations

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ELECTRONICS AND COMMUNICATIONS IN JAPAN PART II-ELECTRONICS 1996年第4期79卷 77-84页

作者： Ishiba, K Komatsu, T Takahara, M Faculty of Engineering Yamanashi University Kofu Japan 400 Graduated in 1994 from the Department of Electronic and Information Engineering where he is currently in the Master's program. He has been engaged in research on optical fiber soliton transmission. Received his B.S. and M.S. degrees in 1993 and 1995 respectively from the Department of Electronic and Information Engineering Yamanashi University. He joined NTT in April 1995. He has been engaged in research on simulation of the optical fiber soliton transmission and on the transmission system with flexibility in transmission speed. Graduated from the Department of Electrical Engineering Yamanashi University in 1965 and received his M.S. degree in 1967. He received his Ph.D. degree later. In 1967 he became a Research Associate of the Department of Electronic Engineering Yamanashi University. In 1991 he became a Professor of Electronic and Information Engineering. He has been engaged in research on special function theory nonlinear circuits optical communication systems and LAN systems. In 1984 he received a Book Award from I.E.I.C.E. In 1990–91 he was on leave at Southampton University. He is a member of IEEE.

In the development of practical multimedia systems, greater capacity is desired in a long-distance large-capacity transmission system. A number of studies have been undertaken to develop a long-distance large-capacity system. Several long-distance transmission experiments for high-density transmission by wavelength demultiplexing method (WDM) have been reported recently. However, more of the experimental examples have reported on soliton transmission than on WDM systems. Hence, the former is considered more advanced. It is necessary to prepare a fiber of a length of approximately 10,000 km for ultralong-distance transmission experiment. Since this is difficult to obtain, repetitive experiments are often the case. However, such an experiment does not disclose the effects of dispersion and loss fluctuation in the fiber. In this paper, the effect of fluctuation in dispersion and loss in the fiber is studied by simulation so that the resilience of the soliton to the variations of the fiber characteristics is evaluated.

关键词： optical soliton dispersion fluctuation loss fluctuation Gordon-Haus jitter

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THE CALLING(SM) NETWORK - A GLOBAL WIRELESS COMMUNICATION-system

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INTERNATIONAL JOURNAL OF SATELLITE COMMUNICATIONS 1994年第1期12卷 45-61页

作者： TUCK, EF PATTERSON, DP STUART, JR LAWRENCE, MH Calling Communications Corporation. 1900 West Garvey Ave South. Suite 200 West Covina CA 91790 USA. Chairman of Calling Communications Corporation. He is also the Managing Director of Kinship Venture Management Inc. the general partner of Kinship Partners 11 and a General Partner of Boundary the general partner of The Boundary Fund. As a venture capitalist he has founded or participated in founding several telecommunications companies including Calling Communications Corporation Magellan Systems Corporation manufactures of Global Positioning System receivers Applied Digital Access manufacturer of DS-3 test access and network performance monitoring equipment Endgate Technology Corporation specialists in satellite phased array antennas and Poynting Systems Corporation. now a division of Reliance Corporation manufacturers of fibre optic transport equipment. He was a founder of Kebby Microwave Corporation where he invented the first solid-state. frequency-modulated commercial microwave link system. The company was acquired by ITT Corporation where he rose to the position of V.P. and Technical Director of ITT North America Telecommunications Inc. Subsequently he was V.P. of Marketing and Engineering at American Telecommunications Inc. (ATC). He was founding Director of American Telecom Inc. a joint venture between ATC and Fujitsu and has served on more than 20 boards of directors including those of three public companies. He has authored articles on microwave engineering and telephone signalling and was a contributor to Reference Data For Radio Engineers. He is a graduate of the University of Missouri at Rolla where he was later awarded an honorary Professional degree and serves on its Academy of Electrical Engineering. Mr Tuck is a Senior Member of the IEEE a Fellow of the Institution of Engineers (Australia) a Professional Member of the AIAA and a registered professional engineer in three states. More than 25 years of experience in the telecommunications industry where he has been responsibl

There is a very large demand for basic telephone service in developing nations, and remote parts of industrialized nations, which cannot be met by conventional wireline and cellular systems. This is the world's largest unserved market. We describe a system which uses recent advances in active phased arrays, fast-packet switching technology, adaptive routeing, and light spacecraft technology, in part based on the work of the Jet Propulsion Laboratory and on recently-declassified work done on the Strategic Defense Initiative, to make it possible to address this market with a global telephone network based on a large low-Earth-orbit constellation of identical satellites. A telephone utility can use such a network to provide the same modern basic and enhanced telephone services offered by telephone utilities in the urban centres of fully-industrialized nations. Economies of scale permit capital and operating costs per subscriber low enough to provide a service to all subscribers, regardless of location, at prices comparable to the same services in urban areas of industrialized nations, while generating operating profits great enough to attract the capital needed for its construction. The bandwidth needed to support the capacity needed to gain these economies of scale requires that the system use K(alpha)-band frequencies. This choice of frequencies places unusual constraints on the network design, and in particular forces the use of a large number of satellites. Global demand for basic and enhanced telephone service is great enough to support at least three networks of the size described herein. The volume of advanced components, and services such as launch services, required to construct and replace these networks is sufficient to propel certain industries to market leadership positions in the early 21st Century.

关键词： LOW EARTH ORBIT SATELLITE COMMUNICATIONS FAST PACKET SWITCHING EARTH FIXED CELLS ADAPTIVE ROUTEING LIGHT SPACECRAFT K(A) BAND PHASED-ARRAY ANTENNAS

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VIRTUAL PROTOTYPING USING KNOWLEDGE - BASED MODELING AND SIMULATION TECHNIQUES

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NAVAL ENGINEERS JOURNAL 1993年第3期105卷 201-212页

作者： SHEA, JG The Author:holds bachelor and master of engineering degrees in mechanical engineering a M.Eng. in engineering management and is currently fulfilling requirements for the M.S. and Ph.D. degrees in computer science at the University of Louisville. He is employed as program manager Phalanx Advanced Engineering Development at the Naval Ordnance Station Crane Div. NavSurfWarCen Louisville Ky. During his tenure with Phalanx Mr. Shea has contributed to system reliability improvement system performance upgrading and the development of the Phalanx HOL (RISC) Computer. Mr. Shea is a member of ASNE the Institute of Electrical and Electronics Engineers American Institute of Aeronautics and Astronautics Society for Computer Simulation International Test & Evaluation Association and the Military Operations Research Society.

Knowledge-based modeling and simulation bridges the gap between ''conventional'' artificial intelligence implementations (such as expert systems) and more traditional computer-aided design techniques. We are currently developing software, whose primary function is to capture a user-input design specification and produce a ''virtual'' rapid prototvpe in the form of executable rule-based code. This code can then be exercised either as an interactive part of a hardware-in-the-loop testbed simulator or as a component of an object-oriented ''behavioral'' simulation environment. While the Phalanx Testbed is the immediate beneficiary of this work, the techniques described have a wide range of application in the modeling of conceptual design and performance characteristics. This paper describes the system architecture and software tools that we are applying to generate virtual rapid prototypes for use in the Phalanx Testbed. Particular attention is paid to defining the intelligent knowledge-capture mechanisms and model generation methodologies that we are using to translate design knowledge and performance requirements into rule-based simulations. The object-oriented programming approach to the merging of ''new'' data with previouslv-captured and stored data is discussed, and the issues of verifying and validating prototypes generated using such partiallv ''reengineered'' models are examined. An application currently in use as an investigative prototype for testbed development, a simple position controller servomechanism used to control the azimuth angle of a target-tracking sensor, is used to illustrate the process.

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QUALITY MANAGEMENT AND master ORDNANCE REPAIR

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NAVAL ENGINEERS JOURNAL 1993年第5期105卷 68-76页

作者： STIMSON, WA MARTINEZ, E William A. Stimson:received his B.S. degree in mathematics from the University of Texas at El Paso in 1964 and his M.S. degree in engineering from the University of Santa Clara in 1971. Mr. Stimson was employed in the aerospace industry for ten years then joined the Naval Ship Weapon Systems Engineering Station in Port Hueneme Calif in 1973. At NSWSES he served ten years as a ship qualification trials project supervisor and seven years as program manager of the Master Ordnance Repair Program. Today Mr. Stimson lives in Charlottesville Va. and is a Ph.D candidate in systems engineering at the University of Virginia majoring in quality management and statistical quality control. Ernest Martinez:received his B.S. degree in computer sciences from National University in 1985. Mr. Martinez was head of combat systems at the Naval Ship Repair Facility Yokosuka Japan for five years returning in 1983 to the Naval Sea Support Center Pacific San Diego Calif. During the next five years he managed the Fleet Modernization Program and was coordinator of the Combat System Readiness Test Program. Today Mr. Martinez lives in San Diego and is employed by the Naval Surface Warfare Center Port Hueneme Calif. as MOR program manager.

Because of the redefinition of national defense needs and the reduction of defense budgets, the management of complex combatant repair is more imperative than ever. To this end, the U.S. Navy is calling for Total Quality Leadership (TQL) strategies from its agencies and contractors. These strategies are derived from well known initiatives of quality management, such as those of Deming. They define the basis of any quality program. Quality methodologies have proven highly effective in the manufacturing sector, but many remain unproven or tentative in service and repair industries. The authors believe that TQL methods can be effective in the repair industry also, but must be developed or adapted to suit the unique characteristics of that industry: high skill, non-rote crafts, with continual customer interface at all levels of operation. In establishing a direction for TQL development, the authors have chosen two elements. The first is the Malcolm Baldrige Quality Improvement program, which provides guidelines for direction. The second is the master Ordnance Repair (MOR) program, which provides the management vehicle. From its beginning in 1983, MOR has been a program of management. The task is explicit in its charter, NAVSEAINST 8000.2, which requires that a MOR contractor manage combat system work and testing. Quality management methods are applied to the MOR program to achieve MOR objectives using Baldrige measurements. Methods are presented which deploy the quality function across the organization. Techniques are provided to improve the company's ability to control its processes and the robustness of its product. These include methods of process analysis that determine added value, ownership, and internal customer. Stress is placed on in-process verification rather than on end-of-process inspection. The recommendations of this paper require no extraordinary skills or costs, but do require a formal and systematic approach to quality issues. The authors believe that

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TOMAHAWK NITROGEN PRESSURIZATION MAINTENANCE - WHY

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NAVAL ENGINEERS JOURNAL 1993年第2期105卷 66-68页

作者： CIARULA, TA NERADKA, VF Cdr. Thomas A. Ciarula: USN was born in Pottstown Pa. He attended Northrop University in Inglewood Calif. where he earned a bachelor of science degree in aircraft maintenance engineering in September 1971. He was selected for Officer Candidate School where he was commissioned an ensign (Aeronautical Maintenance Duty) in August 1972. Cdr. Ciarula has been assigned to VA-37 The AIMD at NAF Kadena Okinawa Japan VXE-6 and the USS Forrestal. He was the wing maintenance for training officer for Air Wing Three at NAS Chase Field in Beeville Tex. and the AIMD officer at NAS Key West Fla. In 1988 Cdr. Ciarula was assigned to the Cruise Missiles Project (PEO-CU) where he was the TASM class desk officer and the director of logistics. While at the Cruise Missiles Project he was awarded his master of science in general administration from Central Michigan University. He is currently assigned to PMA-205 in the Naval Air Systems Command. Vincent F. Neradka:received B.S. and M.S. degrees from the University of Maryland in aerospace engineering in 1964 and 1969 and an MS in technical management from the Johns Hopkins University in 1986. He joined the Johns Hopkins University Applied Physics Laboratory in 1979 working on the Vertical Launching System of the Aegis cruisers. Since that time he has participated in activities on the Phalanx program the SPS-48E radar and long term involvement with the Cruise Missile Program. On the Cruise Missile Program Mr. Neradka has focused on the specification of and testing related to environments. Simulation activities have included modeling of pneumatic systems and NASTRAN dynamic modeling. Mr. Neradka is a registered professional engineer.

This paper discusses the data that were recorded during a three-month accelerated humidity test of two Tomahawk all-up rounds (AURs), one pressurized with dry nitrogen in accordance with the current practice, and the other left unpressurized. Temperature and humidity were recorded inside the canisters and missiles. Data analysis consisted of psychrometric calculations to determine the moisture intrusion into these missiles during the test. The work was carried out in support of a technical effort directed at changing the storage and stowage environmental protection of the Tomahawk missile.

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ASNE LUNCHEON ADDRESS

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NAVAL ENGINEERS JOURNAL 1993年第4期105卷 48-52页

作者： BOWES, WC COMMANDER NAVAL AIR SYSTEMS COMMAND Admiral William Bowes: a native of New York graduated from the University of Idaho and its NROTC Regular Program in June of 1963. He is a 1968 graduate of the United States Naval Test Pilot School and received his master's degree in systems acquisition management from the Naval Postgraduate School in March 1974. Upon receiving his wings in December 1964 he joined the light attack community at the Naval Air Station Lemoore California. He served on combat missions from the Kitty Hawk (CV-63) Enterprise (CVN-65) and Coral Sea (CV-43). Vice Admiral Bowes flew 350 combat missions in Southeast Asia between 1965 and 1972. An experienced test pilot Admiral Bowes has had three tours at the Naval Air Test Center Patuxent River Maryland. Having piloted every jet aircraft that has been in the fleet since the 1960s he has flown more than 5000 hours in over 50 different U.S. and foreign military aircraft. He is an associate fellow in the Society of Experimental Test Pilots. Admiral Bowes began his program management experience in January 1980 in the Naval Air Systems Command as the F/A-18 assistant program manager for systems and engineering. In December 1983 he was assigned as the F-14 aircraft and Phoenix missile system program manager. He managed the Phoenix missile system until June 1985 and the F-14 until November 1987. During that tour of duty the F-14A (PLUS) was delivered to the Navy. He was promoted to rear admiral in November 1987 at which time he was assigned as the director Cruise Missiles Project. In May 1988 he became the first director of the Unmanned Aerial Vehicles Joint Project. In March 1991 Vice Admiral Bowes became the commander of the Naval Air Systems Command. His decorations include the distinguished service medal 3 Legions of Merit 3 Distinguished Flying Crosses 36 Air Medals 2 individual awards 8 Navy Commendation Medals the Vietnamese Air Gallantry Cross and various unit commendations and campaign medals.

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FFG-61 PROTOTYPE DIGITAL TECHNICAL LIBRARY

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NAVAL ENGINEERS JOURNAL 1992年第2期104卷 58-68页

作者： VINROOT, CA ORNER, JG USN Capt. Charles A. Vinroot USN (Ret.)retired from the U.S. Navy in September 1991 following over 27 years of active duty as an engineering duty officer. He holds a BSEE from North Carolina State University and a MSEE and professional degree from the U.S. Naval Postgraduate School. During his naval career he served on USSIndependence (CVA-62) and USSLuce (DLC-7/DDC-38). He also served at Supship Quincy Mass. and Hunters Point Naval Shipyard. He was stationed in Washington D.C. with assignments at CNO (OP 98) ASN (S&L) and the Naval Sea Systems Command. Captain Vinroot was technical director of the Battleship Reactivation Program (PMS 378) technical director of the Destroyer Acquisition Program (PMS 389) and deputy program manager of the Amphibious Warfare and Strategic Sealift Program (PMS 377). Most recently he served as program manager for Gas Turbine Surface Combatants (PMS 314) and Surface Combatants (PMS 330). Captain Vinroot is now employed by PRC Inc. and serves as technical director for the Advanced Technology Division in Crystal City Va. Jeffery G. Ornergraduated from Wittenberg University in Springfield Ohio in 1979 with a bachelor of arts degree in political science and earned a master's of science degree in business from The American University in Washington D.C. in 1982. He has ten years of professional experience with the Naval Sea Systems Command in positions with responsibilities for logistic support planning policy and delivery computer-aided acquisition and logistic support and Fleet Modernization Program (FMP) and ship construction issues. He was a key player in establishing the current FMP integrated logistic support (ILS) process and in implementing of the Ships' Configuration and Logistic Support Information System (SCLSIS). His current position as Fleet Logistic Support Branch head for the Surface Combatant Program includes responsibility for logistic support and management of ship configuration and logistic data for all surface combatant ships (except for Aegis ships). In

USS Ingraham (FFG-61) is the prototype ship for NavSea's Advanced Technical Information system (ATIS). ATIS is a digital technical library, which holds on optical disks the ship's 2,000 technical manuals and 73,000 drawing sheets. It contains a detailed ship's configuration index (derived from SCLSIS) to lead the user to the proper drawing or manual, and it replaces the ship's aperture cards and the second (library) copy of the technical manuals. ATIS, and the data standards established and tested through ATIS development, will be the technical library portion of micro-SNAP and SNAP III. It also forms an important part of NavSea's plans to utilize EDMICS data. This paper describes the goals and technical concepts behind the development of ATIS. Problems encountered, solutions developed, and lessons learned are detailed. Special attention was paid to the application of the Computer Aided Acquisition and Logistic Support (CALS) standards, problems caused by conflicts and ambiguities in those standards, the standards. Original program goals are compared with actual operational experiences. Plans for future expansion are outlined, including applications of this technology in the availability planning and execution process. A comparison is developed among the various methods of optical imaging and their costs and benefits.

关键词： Information Retrieval systems

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EMI - THE ENEMY WITHIN

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NAVAL ENGINEERS JOURNAL 1992年第2期104卷 69-80页

作者： BARON, NT CEBULSKI, DR Neil T. Baronis currently the team leader for the combat system topside design work for amphibious assault auxiliary mine warfare and Coast Guard ships. He sits on the IEEE SCC-28 Committee for personnel radiation hazards and is extensively involved in the EM engineering initiative at NavSea. Mr. Baron has lectured at the MIT Summer Professional Series on the subject of electromagnetic interference. While attending Marquette University he started his career with the Navy as a coop student supporting personnel radiation hazard assessments. After graduating with a BS in bio-medical engineering he took an electronics engineer position in the Systems Electromagnetic Division. Since then he has lectured on Navy training films and has developed several software packages which have pushed the state-of-the-art in EMI assessment. Mr. Baron has prepared several reports and professional papers. He has worked on several professional committees and in February of 1991 was awarded the “Young Engineer of the Year Award” which was presented by the D.C. Council of Engineering and Architectural Societies. Donald R. Cebulskiis currently the head of the Topside Design Division in the Naval Sea Systems Command Weapons and Combat System Directorate. He graduated from the University of Michigan with a bachelor's degree in 1963 and a master's degree in 1977 both in naval architecture and marine engineering. He started his career in 1964 at the Bureau of Ships and joined the Aircraft Carrier Section of the Arrangements Branch in Hull Design. During the past 25 years he has included almost every naval ship type in his ship arrangement experience and in October of 1988 he transferred to the Topside Design and Integration Branch in the System Electromagnetics Division Sea 06. Mr. Cebulski has written several papers on ship arrangements computer aided design and ship topside design. He prepared and presented lectures at the MIT Professional Series on ship topside design and has served on many ASNE committees. He is currently the

Electromagnetic interference (EMI) is one of the major contributors to mission degradation in our fleet today due to the increase in population and sensitivity of both topside and below deck electronic systems. Sensitive combat systems designed to counter intelligent and deceptive targets can be confused by the complex intra-ship EM environment. This can cause identification failure or losing "track" of a hostile or incoming missile or even engaging "friendly targets." Topside design and integration efforts have been used to reduce EMI, but this is not the total solution to the problem. A program of total ship and system EMI assessment and control must be implemented. This program must exploit electromagnetic compatibility (EMC) optimization in electronic circuit design and take advantage of and (in some cases) direct topside shapes and structures to control the propagation of desired and undesired EM energy. Positive and active control of EM design characteristics are absolutely required before optimum combat system effectiveness can be realized. This paper will describe the current topside design process, EMC improvements being made, and how the process is being integrated into, and is dependent upon, the ship design process. It will give examples of some of the major mission degrading EMI problems in the fleet today and how past problems were solved with existing EM analysis programs. It will also discuss the control of EM energy in new design through the use of techniques being developed such as ray tracing and ray casting. The paper projects where the challenges lie for future topside and EM engineering designers and describes how the equipment technology transfer process must be better integrated to meet the challenge of effective EMI control.

关键词： Signal Interference

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