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FULL-WAVE SOLUTION OF DIELECTRIC LOADED WAVE-GUIDES AND SHIELDED MICROSTRIPS UTILIZING FINITE-DIFFERENCE AND THE CONJUGATE-GRADIENT METHOD

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INTERNATIONAL JOURNAL OF MICROWAVE AND MILLIMETER-WAVE COMPUTER-AIDED ENGINEERING 1991年第4期1卷 346-357页

作者： NARAYANAN, V MANELA, M LADE, RK SARKAR, TK Department of Electrical and Computer Engineering Syracuse University Syracuse New York 13244-1240 Viswanathan Narayanan was born in Bangalore India on December 14 1965. He received the BE degree in Electronics and Communications from B.M.S. College of Engineering Bangalore in 1988. He joined the Department of Electrical Engineering at Syracuse University for his graduate studies in 1989 where he is currently a research assistant. His research interests are in microwave measurements numerical electromagnetics and signal processing. Biographies and photos are not available for M. Manela and R. K. Lade. Tapan K. Sarkar (Sf69-M'76-SM'X1) was born in Calcutta. India on August 2 1948. He received the BTech degree from the Indian Institute of Technology Kharagpur India in 1969 the MScE degree from the University of New Brunswick Fredericton Canada in 1971. and the MS and PhD degrees from Syracuse University. Syracuse NY in 1975. From 1975-1976 he was with the TACO Division of the General Instruments Corporation. He was with the Rochester Institute of Technology (Rochester NY) from 1976-1985. He was a Research Fellow at the Gordon Mckay Laboratory Harvard University Cambridge MA from 1977 to 1978. He is now a Professor in the Department of Electrical and Computer Engineering Syracuse University. His current research interests deal with numerical solutions of operator equations arising in electromagnetics and signal processing with application to system design. He obtained one of the “ best solution” awards in May 1977 at the Rome Air Development Center (RADC) Spectral Estimation Workshop. He has authored or coauthored more than 154 journal articles and conference papers and has written chapters in eight books. Dr. Sarkar is a registered professional engineer in the state of New York. He received the Best Paper Award of the IEEE Transactions on Electromagnetic Compatibility in 1979. He was an Associate Editor for feature articles of the lEEE Antennas arid Propagation Sociefy Newsletter and was

Dynamic analysis of waveguide structures containing dielectric and metal strips is presented. The analysis utilizes a finite difference frequency domain procedure to reduce the problem to a symmetric matrix eigenvalue problem. Since the matrix is also sparse, the eigenvalue problem can be solved quickly and efficiently using the conjugate gradient method resulting in considerable savings in computer storage and time. Comparison is made with the analytical solution for the loaded dielectric waveguide case. For the microstrip case, we get both waveguide modes and quasi-TEM modes. The quasi-TEM modes in the limit of zero frequency are checked with the static analysis which also uses finite difference. Some of the quasi-TEM modes are spurious. This article describes their origin and discusses how to eliminate them. Numerical results are presented to illustrate the principles.

关键词： Waveguides

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USE OF EXPERT SYSTEMS TO ENHANCE LOGISTIC MANAGEMENT

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NAVAL ENGINEERS JOURNAL 1990年第3期102卷 119-126页

作者： CASSANO, AJ The Author:is a logistics policy officer on the staff of the Naval Supply Systems Command (NavSup). He has served with ships of both the Atlantic and the Pacific Fleets and has had assignments in material management at an inventory control center a supply center and at an industrial activity. He is a project officer for a FY 90 effort to design and implement expert systems to enhance material management and logistics program management at NavSup inventory control points. He is a 1972 NROTC graduate of the Pennsylvania State University. He holds a master's degree in business administration from the University of Florida.

Expert Systems are at work in a variety of technical and managerial applications. Using custom designed knowledge bases and decision rules, expert systems prompt the user to explain a problem and then offer solutions or advice on how to proceed to solve the problem. A properly designed expert system maximizes the virtues of human experts by emphasizing performance and reliability, by being easy to use, by being able to explain its advice and entire line of reasoning and by being capable of interfacing with other computer systems and databases. This paper surveys the development of expert systems and offers a discussion of some aspects of expert system design and introduction. The paper concludes with a review of Navy logistics expert systems now in design.

关键词： Artificial Intelligence

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SHIP SERVICE ELECTRICAL SYSTEMS - designING FOR SURVIVABILITY

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NAVAL ENGINEERS JOURNAL 1990年第5期102卷 32-36页

作者： CERMINARA, J KOTACKA, RO John Cerminara:is a principal engineer with Westinghouse Machinery Technology Division Electrical Systems Department. He holds a B.S. degree in electrical engineering from the University of Pittsburgh. He is a registered professional engineer and a member of IEEE ASNE and the Ship Steering Group of the Combat Survivability Division of ADPA. Mr. Cerminara has had over 30 years of multidiscipline experience ranging from engineering and construction in heavy industry to standards and publications. Past assignments include DOE/ NASA wind turbine project manager for Westinghouse and task leader of MTD electrical systems. Most recent assignments have included hull mechanical and electrical (HM&E) distributive system survivability analyses of the LSD-41 mobility mission area and application and validation of NavSea computer-aided design of Survivable Distributive System (CADSDiS) Program. Rolf O. Kotacka:is presently a ship systems engineer in the Ship Systems Engineering Branch of the Naval Sea Systems Command Engineering Directorate where his primary responsibility is ship system survivability. He is a 1977 graduate of SUNY Maritime College where he received his bachelor of engineering degree in marine electrical engineering as well as a U.S. Coast Guard Third Assistant Engineer License and a commission in the U. S. Naval Reserve. Upon graduation Mr. Kotacka was employed by Charleston Naval Shipyard as a field engineer until 1981 where he gained his background in surface ship HM&E systems and equipment. He then transferred to the Supervisor of Shipbuilding Conversion and Repair Groton where he served as a senior electrical engineer monitoring the design and construction of Trident and 688 class submarines and received the Meritorious Unit Citation. Prior to his present position Mr. Kotacka was the life cycle manager for diesel generator sets in the Naval Sea Systems Command's Generators Branch. He has coauthored several papers dealing with power generation for ASE and SNAME. Mr. Kotacka is also a lieutena

This paper highlights the survivability concerns in the design of ship service power systems. The paper gives a brief description of what constitutes a typical ship service electric power system and concentrates on electric power generation and associated controls. Established survivability design principles and guidelines are highlighted and the application of those guidelines are discussed. General Specifications (Gen Specs) for Ships of the U.S. Navy are cited as the cornerstone for design. Specific design criteria are cited as well as the rationale associated with the survivability design guidelines pertaining to power generation and distribution. The application of these survivability design guidelines plus the use of the deactivation diagram/damage tolerance analysis cited in the Gen Spec section 072e will enhance overall design and help ensure survivable electric power systems for surface combatants.

关键词： Warships

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FLAMMABILITY AND TOXICITY OF COMPOSITE-MATERIALS FOR MARINE VEHICLES

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NAVAL ENGINEERS JOURNAL 1990年第5期102卷 45-54页

作者： SEVART, JL GRIFFIN, OH GURDAL, Z WARNER, GA Jeffrey L. Sevart:is a native of Kansas and a 1985 graduate of Kansas State University with a B.S. in mechanical engineering (magna cum laude). After working as a stress analysis engineer at Boeing Military Airplane Company in Wichita Kans. he attended Virginia Polytechnic Institute and State University and received an M.S. in engineering mechanics in February 1988. He currently resides in Akron Ohio working as a research engineer in tire composites research at The Goodyear Tire and Rubber Company. O. Hayden Griffin Jr.:received his B.S. and M.S. in mechanical engineering from Texas Tech University in 1970 and 1971 respectively. He received his Ph.D. in engineering mechanics from Virginia Polytechnic Institute and State University in 1980. Prior to joining the faculty of Virginia Polytechnic Institute and State University as associate professor of engineering science and mechanics in September 1985 he was employed at the U.S. Naval Surface Warfare Center (Dahlgren Virginia) BF Goodrich Tire Group (Akron Ohio) the Bendix Advanced Technology Center (Columbia Maryland) and the Johns Hopkins University Applied Physics Laboratory (Laurel Maryland). He is currently an associate director of the Virginia Institute for Material Systems. He is a registered professional engineer in Virginia and is a member of the American Society of Mechanical Engineers and the American Society for Composites. Zafer Gürdal:received his M.S. in mechanical and aerospace engineering from Illinois Institute of Technology in 1981 and his Ph.D. in aerospace engineering from Virginia Polytechnic Institute and State University in 1985. He worked as a research associate in the Aerospace and Ocean Engineering Department at Virginia Tech before joining the Engineering Science and Mechanics Department as an assistant professor in September 1985. Professor Gürdal's research interests include: composite structures failure mechanics of composites structural optimization and damage tolerant design. He is a member of the American Institute

Characteristics of both thermoplastic and thermoset composite materials as they pertain to marine vehicle applications are discussed. Comparison of various material selection factors such as strength, damage and moisture resistance, and flammability and toxicity as well as cost and availability of thermoset and thermoplastic composite materials are presented. Methods for testing and reducing the flammability and toxicity are discussed. Many commercially available composite systems are reported to provide favorable characteristics for marine applications. Although there seems to be a need for improved production technology for thermoplastics, they present potential advantages in physical properties over thermoset composites.

关键词： Composite Materials

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THE EVOLUTION OF MACHINERY CONTROL-SYSTEMS ABOARD UNITED-STATES-NAVY GAS-TURBINE SHIPS

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NAVAL ENGINEERS JOURNAL 1989年第3期101卷 102-113页

作者： PREISEL, JH The author:is the DDG-51 program manager at the Naval Ship Systems Engineering Station in Philadelphia. He graduated from the U.S. Naval Academy with a B.S. in marine engineering in 1972 and completed graduate studies at the Naval Postgraduate School in 1978. In addition to an initial sea tour aboard a destroyer he has served at Charleston Naval Shipyard and at NavSea in both ship design and modernization. He recently completed a short assignment as the NavSea representative at the G.E. Simulation and Control System Department during the design manufacturing and testing of the DDG-51 Machinery Control System. Commander Preisel is a member of ASNE Sigma Xi ASME and SNAME and is a registered professional engineer.

Almost 25 years ago, the U.S. Navy committed to gas turbines for propulsion and electrical power generation for surface combatants. Jet engines from the aerospace industry were “marinized” and specified for several designs. Today, there are over one hundred gas turbine powered surface ships; almost half also have gas turbine generators. This fundamental change, notably from steam to gas turbine power, brought with it a new philosophy in the way prime movers are controlled and monitored. Unmanned engineering spaces were a fundamental part of the new design. Direct thrust control in the hands of the helmsman was possible. Possibly the most profound effect was the introduction of electronics in the main engineering spaces on a large scale. Data buses for data logging and bell logging were used as a means to reduce the tedium of normal watch standing. Gas turbine machinery control systems have entered a second generation with the introduction of the DDG-51 class destroyer and the AOE-6 supply ship. Hard-wired analog interfaces have given way to digital interfaces over asynschronous multiplexed data buses. Dedicated pushbuttons and indicators have given way to keyboards and plasma displays. Single use microprocessors with firmware coding have given way to standard microcomputers and general high order language (HOL) software code. This paper will trace the control systems' evolution from the Spruance and Perry classes to today's gas turbine designs. An attempt will be made to draw a sense of direction from this evolution. An in-depth explanation of the DDG-51 control system will be offered, as well as suggestions as to the future of control systems for gas turbine ships. Particular emphasis will be placed on the man-machine interface and the maintenance philosophy for both the control system hardware and software.

关键词： Gas Turbines

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COMPARATIVE-ASSESSMENT OF UNITED-STATES AND FOREIGN BUOY TENDERS

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NAVAL ENGINEERS JOURNAL 1989年第4期101卷 136-136页

作者： KEHOE, JW BROWER, KS TUTTLE, JG Capt. James W. Kehoe Jr. USN (Ret.):is well known for his work in comparative naval architecture studies of U.S. and foreign warship design practices for which he received the American Society of Naval Engineer's Gold Medal Award for 1981 and the Legion of Merit in 1982. He received the ASNE “Jimmie” Hamilton Award for 1983. He is currently a partner in Spectrum Associates Inc. Arlington Virginia. Prior to his retirement in 1982 his naval career included sea duty aboard three destroyers and three aircraft carriers including command of a destroyer and engineer officer of an aircraft carrier. Kenneth S. Brower:is a partner in Spectrum Associates Inc. a naval engineering firm which he founded in 1978 which is currently engaged in the design of naval ships comparative naval architecture studies and the development of ship design synthesis computer programs. A graduate in naval architecture from the University of Michigan he has contributed to the design of numerous warships and merchant ships as well as several frigate designs for foreign military sales. Mr. Brower has been the author or coauthor of numerous technical studies and articles. He received the ASNE “Jimmie” Hamilton Award for 1983. LCdr. John G. Tuttle USCG:is a graduate of the New York Maritime College and the Naval Construction and Engineering Program at MIT. Prior to joining the Coast Guard he was a naval architect for the Navy. He has served in the Marine Safety Offices in New Orleans and Boston. He has also been an instructor in the marine engineering program at the Coast Guard Academy. He was a project officer in the Office of R&D supporting buoy tender and patrol boat acquisitions. He is currently assigned as technical manager of the Buoy Tender Replacement Project in the Office of Acquisition at USCG Headquarters.

The paper reports the results of a comparative study of seven modern foreign buoy tenders and two older U.S. buoy tenders that was conducted by the U.S. Coast Guard as part of its current project to replace its older medium size (WLM) and large seagoing (WLB) buoy tenders. As part of the assessment, the authors visited the foreign ships to observe them conducting buoy tending operations, to review engineering design data, and to discuss buoy tender design, technology and operations with the cognizant operating authorities. The buoy tenders included the Canadian 4,800-ton Type 1100 and 2,800-ton Type 1050, the British 2,900-ton Mermaid , the Swedish 1,200-ton Baltica , the Norwegian 1,100-ton Skomvaer , the Dutch 700-ton Rotterdam , and the Italian 600-ton MIF. The U.S. buoy tenders included the Coast Guard 470-ton, 157-foot WLM and 1,000-ton, 180-foot WLB (SLEP), which were also visited and included in the study for comparative purposes. The study's objectives were to identify design practices and technology incorporated in the foreign buoy tenders that the U.S. Coast Guard could adapt in designing future buoy tenders and to determine if any foreign buoy tender design meets the Coast Guard requirements for WLB and WLM replacements. The design characteristics, technology, and unique features of each buoy tender are described and compared. Lessons learned from the study which could be beneficial in the design of future Coast Guard buoy tenders are identified. Finally, the capabilities of the foreign buoy tenders are assessed in relation to current Coast Guard requirements.

关键词： Naval Vessels

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REMEDIATION OF CONTAMINATED GROUND-WATER USING BIOLOGICAL TECHNIQUES

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GROUND WATER MONITORING AND REMEDIATION 1989年第1期9卷 105-119页

作者： FLATHMAN, PE JERGER, DE BOTTOMLEY, LS Paul E. Flathman is senior microbiologist at O.H. Materials Corp. (P.O. Box 551 Findlay OH 45839). Flathman has more than eight years of field experience in the biological cleanup and environmental restoration of areas contaminated with petroleum hydrocarbons and other hazardous organic wastes. He has a B.S. in biology/chemistry from The Defiance College Defiance Ohio and an M.S. in microbiology from Bowling Green State University Bowling Green Ohio. The cometabolic biodegradation of anthropogenic organic compounds was the focus of his graduate research. Flathman was the 1985 recipient of the Ohio Water Pollution Control Conference's F.H. Waring A ward in recognition of outstanding achievement in the field of industrial waste control. He is a Registered Class III (Advanced) Wastewater Treatment Plant Operator (Ohio EPA) a Registered Class III (Advanced) Wastewater Laboratory Analyst (Ohio WPCA-LAC) and a Registered Microbiologist (The National Registry of Microbiologists American Academy of Microbiology). He is a member of eight professional organizations and has served as chairman and for three years as a member of the Executive Committee of the Northwest Central Ohio Section of the American Chemical Society. Flathman is also a member of three subcommittees and a task group participant of the American Society for Testing and Materials. The focus of his current research is the enhanced biodegradation of hazardous organic contaminants following spills of these materials in the environment. Douglas E. Jerger is manager of the Biorestoration Program at O.H. Materials Corp. (P. O. Box 551 Findlay OH 45839). Jerger has more than 15 years experience in environmental microbiology and bioprocess engineering with NASA—Manned Spacecraft Center Environmental Control Technology Corp. Institute of Gas Technology and University of Florida. He is currently completing research toward his Ph.D. at the University of Michigan. Jerger is a member of four professional organizations and has coauthored more than 20 public

On-site biological cleanup following spills of biodegradable hazardous organic compounds in lagoon, soil, and ground water environments is a cost-effective technique when proper engineering controls are applied. Biodegradation of hazardous organic contaminants by microorganisms minimizes liability by converting toxic reactants into harmless end *** case histories presented in this paper detail:• Bench-scale evaluation of the potential for biological remediation in the spill site matrix• Field implementation of biological treatment ***-effectiveness, minimal disturbance to existing operations, and on-site destruction of spilled contaminants are several of the advantages identified for implementing biodegradation as a technique for spill cleanup and environmental restoration.

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BOTTOM BOUNCE ARRAY SONAR SUBMARINE (BBASS)

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NAVAL ENGINEERS JOURNAL 1989年第5期101卷 59-72页

作者： JACKSON, HA NEEDHAM, WD SIGMAN, DE USN (RET.) Capt. Harry A. Jackson USN (Ret.) is a graduate of the University of Michigan in naval architecture and marine engineering and completed the General Electric Company's 3-year advanced engineering course in nuclear engineering. He has been an independent consulting engineer and participated in projects involving deep submergence waste disposal water purification and submarine design both commercial and government. Cdr. William D. Needham USN is currently assigned as the repair officer of USS Hunley (AS-31) in Norfolk Virginia. He received a regular commission through NROTC at Duke University where he graduated magna cum laude in mechanical engineering. Selected for the Nuclear Power Program he served as a division officer on the USS Grayling (SSN-646) as the production training assistant at the MARE Prototype Reactor in New York and as blue crew engineer of the USS Nathan Hale (SSBN-623) where he completed the requirements to be designated qualified for command of submarines. Following line transfer to the EDO community in 1981 he completed a tour as nuclear repair officer (Code 310) at Norfolk Naval Shipyard and earned master of science in materials science and ocean engineer's degrees at MIT. His awards include the Meritorius Service Medal Navy Commendation Medal Navy Achievement Medal Spear Foundation Award and the Vice Admiral C.R. Bryan Award. Cdr. Needham also holds a master of arts degree in business management from Central Michigan University. Capt. Jackson was technical director of Scorpion Search Phase II. The on-site investigation included descending over 12 000 feet to the bottom of the ocean. He was also supervisor of one of the Navy's largest peacetime shipbuilding and repair programs. His responsibilities included supervision of design production and contract administration. Capt. Jackson was third from the top in managaement of a major shipyard and responsible for design material procurement work order and financial control of two major surface ship prototypes as well a

Anticipated technological advances in the quieting of potential adversary submarines mandate the use of increasingly effective detection systems for U.S. ASW forces. Based on the assumptions that sonar will continue to be the primary means of detection and that the effectiveness of each individual sonar element will not change markedly, one must increase the projected area of the sonar array to improve its capability. The primary SSN mission of anti-submarine warfare will hence require increasing the hull area devoted to the primary sonar detection system. A revolutionary hull form is proposed that maximizes the area available for this purpose. The advantages and disadvantages of this hull form are discussed and feasibility study level design parameters and arrangements presented.

关键词： Submarines

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A COMPUTER-MODEL FOR DAMAGE TOLERANCE ANALYSIS

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NAVAL ENGINEERS JOURNAL 1988年第5期100卷 59-68页

作者： FAIRHEAD, DL COHEN, SL Steven L. Cohen:heads the Survivability and Damage Control Office at the David Taylor Research Center. His career has addressed a wide range of technical and management responsibilities in the areas of HM&E systems design magnetic signatures system safety of surface ships and submarines shipboard energy conservation RDT&E (future fleet) life cycle costing survivability damage control CBR defense and management information systems. He has participated in all phases of the ship design process from conceptual design through ship construction operational evaluation and overhaul/modernization. Mr. Cohen is a graduate of Drexel University where he majored in electrical engineering and has more recently taken courses in the fields of systems engineering program management costing and microcomputer-based information and decision support systems.

A computer model is being developed by the David Taylor Research Center (DTRC) to analyze the tolerance of surface ship combat systems to combat-induced and self-inflicted damage. The work is being done in support of the Navy's hull, mechanical and electrical design effort to improve the survivability of surface ship combat systems. The DDG-51 Detailed design Specifications (Section 072f) and the General Specifications for Ships of the U.S. Navy (1986 Section 072e) both require that damage tolerance analyses be performed. A damage tolerance analysis shows the effect of damage on vital auxiliary and electrical systems and relates these damage effects to the capability of the ship to continue performing its combat mission at a prescribed level. designated the Computer Aided design of Survivable Distributed Systems (CADSDiS) model, DTRC's deterministic analytical tool consists of portable software to be used by personnel at the activity responsible for the ship design. The model's graphics electrical module is now operating on Digital Equipment Corporation VAX computers at several Navy and commercial activities. Because CADSDiS is highly interactive, it becomes an integral part of the design cycle; this is its major benefit. Thus, damage tolerance analysis information is available to personnel designing the ship within hours or days rather than weeks or months. This computer model will help ensure that the survivability principles of separation and redundancy are incorporated into ship design and are realized in the ship as built.

关键词： Warships

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NAVAL SHIP design - EVOLUTION OR REVOLUTION

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NAVAL ENGINEERS JOURNAL 1988年第3期100卷 40-52页

作者： TIBBITTS, BF KEANE, RG RIGGINS, RJ Captain Barry Tibbitts USN: was graduated from the U.S. Naval Academy in 1956 and subsequently served as a gunnery division officer in an attack aircraft carrier and as gunnery officer operations officer and chief engineer in two diesel submarines. He attended MIT from 1962–1965 earning a master of science in mechanical engineering and a naval engineers degree. Early assignments as an engineering duty officer included SRF Yokosuka CINCPACFLT staff and SupShip Pascagoula. From 1976 to 1987 he served in a variety of senior ship design assignments: CVV ship design manager director NAVSEC Hull and Ship Design Divisions director NavSea Ship Design Management and Integration Office commander David Taylor Naval Ship R&D Center and director NavSea Ship Design Group. Recently retired but recalled to active duty he is the professor of naval construction and engineering at MIT. He has received seven personal decorations including two Legion of Merit awards. Robert G. Keane Jr.:is currently the deputy director of the NavSea Ship Design Group. He has been employed by NavSea and its predecessor organizations for over twenty years. He is a graduate of The Johns Hopkins University from which he received his B.E.S. degree in mechanical engineering in 1962. He received his M.E. degree in mechanical engineering in 1967 from Stevens Institute of Technology and in 1970 his M.S.E. degree in naval architecture and marine engineering from the University of Michigan. Mr. Keane held increasingly responsible design positions involving ship arrangements hull equipment hull form and hydrodynamic performance before being selected in 1981 for the Senior Executive Service to be director of the Naval Architecture Subgroup. Following an assignment at the David Taylor Research Center as assistant for transition of ship engineering technology he served as director of the Ship Survivability Subgroup until assuming his current position in 1985. He is an active member of ASNE SNAME and ASE. Robert Riggins:received a B.S. in mechanical

Some fairly radical changes to the naval ship design process occurred during the 1970s. The decade of the 80s has also witnessed a steady stream of changes. One of the most significant was the establishment of the Ship Characteristics Improvement Board (SCIB) in the Office of the Chief of Naval Operations (OpNav), and the resulting influence on the dialog between the military requirements decision makers and the Navy's ship designers. Other changes have occurred for which the impacts are less clear. These include establishment of the chief engineer of the Navy (ChEng) position, creation of the Space and Naval Warfare Systems Command (SpaWar) and OpNav's “Revolution at Sea” initiative. This paper will describe and discuss these and other changes, and comment on the resultant impact. The authors will attempt to present a global view of the total pattern of changes and try to discern if we are on a path of revolution, or merely normal evolution.

关键词： NAVAL VESSELS

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