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Native and generic parallel programming environments on a transputer and a PowerPC platform

Concurrency and Computation: Practice and Experience 1996年第1期8卷

作者： A.G. Hoekstra P.M.A. Sloot F. van der Linden M. van Muiswinkel J.J.J. Vesseur L.O. Hertzberger Parallel Scientific Computing & Simulation Group Computer Systems Department Faculty of Mathematics and Computer Science University of Amsterdam Kruislaan 409 1098 SJ Amsterdam The Netherlands

Genericity of parallel programming environments, enabling development of portable parallel programs, is expected to result in performance penalties. Furthermore, programmability and tool support of programming environments are important issues if a choice between programming environments has to be made. In this paper we propose a methodology to compare native and generic parallel programming environments, taking into account such competing issues as portability and performance. As a case study, this paper compares the Iserver-Occam, Parix, Express and PVM parallel programming environments on a 512-node Parasytec GCel. Furthermore, we apply our methodology to compare Parix and PVM on a new architecture, a 32-node Parsytec PowerXplorer, which is based on the PowerPC chip. In our approach we start with a representative application and isolate the basic (environment)-dependent building blocks. These basic building blocks, which depend on floating-point performance and communication capabilities of the environments, are analysed independently. We have measured point-to-point communication times, global communication times and floating-point performance. All information is combined into a time complexity analysis, allowing comparison of the environments on different degrees of functionality. Together with demands for portability of the code and development time (i.e. programmability), an overall judgement of the environments is given.

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A comparison of the Iserver-Occam, Parix, Express, and PVM programming environments on a parsytec GCel

A comparison of the Iserver-Occam, Parix, Express, and PVM p...

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International Conference and Exhibition on High-Performance Computing and Networking, HPCN 1994

作者： Sloot, P.M.A. Hoekstra, A.G. Hertzberger, L.O. Parallel Scientific Computing & Simulation Group Department of Computer Systems Faculty of Mathematics and Computer Science University of Amsterdam Kruislaan 403 Amsterdam1098 SJ Netherlands

ISBN: (纸本)9783540579816

We compare the Iserver-Occam, Parix, PVM, and Express parallel programming environments on a Parsytec GCel with 512 T805 transputers. The comparison will be made by a detailed analysis of the performance of one particular application. In our approach we start with this application and isolate the basic (environment dependent) building blocks. These basic building blocks, which depend on floating point performance and communication capabilities of the environments, are analysed independently. We have measured point to point communication times, global communication times and floating point performance. All information will be combined into a time complexity analysis, allowing us to compare the environments on all relevant degrees of functionality. Together with demands for portability of the code, and development time (i.e. programmability), an overall judgement of the environments can be made. © 1994, Springer Verlag. All rights reserved.

关键词： Transputers

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DIPOLAR UNIT SIZE IN COUPLED-DIPOLE CALCULATIONS OF THE SCATTERING MATRIX-ELEMENTS

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OPTICS LETTERS 1993年第15期18卷 1211-1213页

作者： HOEKSTRA, AG SLOOT, PMA Parallel Scientific Computing Group department of Computer Systems Faculty of Mathematics and Computer Science University of Amsterdam

The coupled-dipole method is widely used to calculate the light-scattering matrix S from arbitrary particles. An important parameter in the model is the size of the dipolar subunits. Usually a size of approximately 1/10 to approximately 1/20 of the wavelength of the incident light is sufficient for accurate calculations. However, it was noted that accurate S-34 calculations require much smaller dipolar subunits. We show that this conclusion is too pessimistic, by examining the sensitivity of the S-34 elements on surface roughness of spherical particles. Furthermore we give an example of an accurate S-34 calculation with dipolar subunits as large as 1/10 of the wavelength.

关键词： .dipoles surface roughness CD method Coupled Dipole Scattering Matrix dipolar subunits

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Trace driven analysis of write caching policies for disks 93

Trace driven analysis of write caching policies for disks

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1993 ACM SIGMETRICS Conference on Measurement and Modeling of computer systems, SIGMETRICS 1993

作者： Biswas, Prabuddha Ramakrishnan, K.K. Towsley, Don Office and Teamware Engineering Group Digital Equipment Corporation 110 Spitbrook Road NashuaNH United States Distributed Systems Architecture and Performance Group Digital Equipment Corporation 550 King Street LittletonMA United States Computer Science Department University of Massachusetts AmherstMA United States

ISBN: (纸本)0897915801

The I/O subsystem in a computer system is becoming the bottleneck as a result of recent dramatic improvements in processor speeds. Disk caches have been effective in closing this gap but the benefit is restricted to the read operations as the write I/Os are usually committed to disk to maintain consistency and to allow for crash recovery. As a result, write I/O traffic is becoming dominant and solutions to alleviate this problem are becoming increasingly important. A simple solution which can easily work with existing file systems is to use non-volatile disk caches together with a write-behind strategy. In this study, we look at the issues around managing such a cache using a detailed trace driven simulation. Traces from three different commercial sites are used in the analysis of various policies for managing the write cache. We observe that even a simple write-behind policy for the write cache is effective in reducing the total number of writes by over 50%. We further observe that the use of hysteresis in the policy to purge the write cache, with two thresholds, yields substantial improvement over a single threshold scheme. The inclusion of a mechanism to piggyback blocks from the write cache with read miss I/Os further reduces the number of writes to only about 15% of the original total number of write operations. We compare two piggybacking options and also study the impact of varying the write cache size. We briefly looked at the case of a single non-volatile disk cache to estimate the performance impact of statically partitioning the cache for reads and writes. © 1993 ACM.

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computer-SYSTEM architecture CONCEPTS FOR FUTURE COMBAT systems

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NAVAL ENGINEERS JOURNAL 1990年第3期102卷 43-62页

作者： ZITZMAN, LH FALATKO, SM PAPACH, JL Dr. Lewis H. Zitzman:is the group supervisor of the Advanced Systems Design Group Fleet Systems Department The Johns Hopkins University Applied Physics Laboratory (JHU/APL). He has been employed at JHU/APL since 1972 performing applied research in computer science and in investigating and applying advanced computer technologies to Navy shipboard systems. He is currently chairman of Aegis Computer Architecture Data Bus and Fiber Optics Working Group from which many concepts for this paper were generated. Dr. Zitzman received his B.S. degree in physics from Brigham Young University in 1963 and his M.S. and Ph.D. degrees in physics from the University of Illinois in 1967 and 1972 respectively. Stephen M. Falatko:was a senior engineering analyst in the Combat Systems Engineering Department Comptek Research Incorporated for the majority of this effort. He is currently employed at ManTech Services Corporation. During his eight-year career first at The Johns Hopkins University Applied Physics Laboratory and currently with ManTech Mr. Falatko's work has centered around the development of requirements and specifications for future Navy systems and the application of advanced technology to Navy command and control systems. He is a member of both the Computer Architecture Fiber Optics and Data Bus Working Group and the Aegis Fiber Optics Working Group. Mr. Falatko received his B.S. degree in aerospace engineering with high distinction from the University of Virginia in 1982 and his M.S. degree in applied physics from The Johns Hopkins University in 1985. Mr. Falatko is a member of Tau Beta Pi Sigma Gamma Tau the American Society of Naval Engineers and the U.S. Naval Institute. Janet L. Papach:is a section leader and senior engineering analyst in the Combat Systems Engineering Department Comptek Research Incorporated. She has ten years' experience as an analyst supporting NavSea Spa War and the U.S. Department of State. She currently participates in working group efforts under Aegis Combat System Doctrin

This paper sets forth computer systems architecture concepts for the combat system of the 2010–2030 timeframe that satisfy the needs of the next generation of surface combatants. It builds upon the current Aegis computer systems architecture, expanding that architecture while preserving, and adhering to, the Aegis fundamental principle of thorough systems engineering, dedicated to maintaining a well integrated, highly reliable, and easily operable combat system. The implementation of these proposed computer systems concepts in a coherent architecture would support the future battle force capable combat system and allow the expansion necessary to accommodate evolutionary changes in both the threat environment and the technology then available to effectively counter that threat. Changes to the current Aegis computer architecture must be carefully and effectively managed such that the fleet will retain its combat readiness capability at all times. This paper describes a possible transition approach for evolving the current Aegis computer architecture to a general architecture for the future. The proposed computer systems architecture concepts encompass the use of combinations of physically distributed, microprocessor-based computers, collocated with the equipment they support or embedded within the equipment itself. They draw heavily on widely used and available industry standards, including instruction set architectures (ISAs), backplane busses, microprocessors, computer programming languages and development environments, and local area networks (LANs). In this proposal, LANs, based on fiber optics, will provide the interconnection to support system expandability, redundancy, and higher data throughput rates. A system of cross connected LANs will support a high level of combat system integration, spanning the major warfare areas, and will facilitate the coordination and development of a coherent multi-warfare tactical picture supporting the future combatant command st

关键词： computer architecture

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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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RETROFITTING OF BULBOUS BOWS ON UNITED-STATES NAVY AUXILIARY AND AMPHIBIOUS WARSHIPS

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NAVAL ENGINEERS JOURNAL 1984年第6期96卷 40-51页

作者： CHUN, SK HOUGH, JJ ENGLE, AH FUNG, SC Stephen K. Chunis a graduate of the Maritime College of the State University of New York class of 1981 from which he received a B.E. degree in naval architecture and his license as a Third Assistant Engineer from the U.S. Coast Guard. Since graduation he has worked for the U.S. Navy as a naval architect with the Hull Form and Hydrodynamics Performance Division (SEA 55W3) of the Naval Sea Systems Command. Currently he is the task leader for hydrodynamic design for the DDG-51. He is also responsible for bulbous bow and appendage design for surf ace ships. Mr. Chun is a member of ASNE SNAME and ASE. Jeffrey J. Hough:is currently a naval architect with the Hull Form and Hydrodynamic Performance Division (SEA 55VV3) of the Naval Sea Systems Command (NA VSEA). In his current capacity he is a member of the Surface Ship Hydrodynamics Branch and is the divisional coordinator for computer supported design (CSD) technical director for the hull form design system (HFDS) Hull Engineering Group (SEA 55) assistant coordinator for CSD SEA 55 CSD coordinator for the DDG-51 contract design and SEA 55W3 project engineer for aircraft carrier/aviation support ship hydrodynamics. Mr. Hough received his B.S.E. degree in naval architecture and marine engineering in 1978 and his M.S.E. degree in naval architecture and marine engineering in 1979 from the University of Michigan. He began his career with the U.S. Navy in 1979 as an Engineer-in-Training in the Ship Design and Integration Directorate of NAVSEA. Prior to his current assignment Mr. Hough was the technical director responsible for the hull form and hydrodynamics energy conservation program and technical specialist for design practices for resistance and powering margins and hull form geometry. A member of ASNE since 1979 Mr. Hough is also a member of SNAME ASE and the U.S. Naval Institute. Allen H. Engleis a naval architect with the Hull Form Design and Performance Division of the Naval Sea Systems Command. He received his B.S. degree in engineering science from th

To meet energy conservation goals of the U.S. Navy, its attention has been focused on ways to reduce individual ship total resistance and powering requirements. One possible method of improving ship powering characteristics is by modifying existing individual ship hulls with the addition of bulbous bows. This paper will identify the merits of retrofitting bow bulbs on selected U.S. Navy auxiliary and amphibious warfare ships. A procedure for performing a cost-benefit analysis will be shown for candidate ship classes. An example of this technique for an amphibious warfare ship will also be provided. A brief discussion of future methods to be used for bulbous bow design such as application of systematic model test data and numerical hydrodynamic techniques will be given.

关键词： NAVAL VESSELS

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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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ARCTIC TRAFFICABILITY PROGRAM - A REVIEW

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NAVAL ENGINEERS JOURNAL 1984年第3期96卷 169-175页

作者： VOELKER, R GLEN, IF SEIBOLD, F BAYLY, I Richard Voelker:is Vice President of ARCTEC Incorporated a firm specializing in cold regions technology. He has been responsible for the management of thePolarClass Traffic-ability Program since its inception and annually participates in the field data collection in the Arctic. His prior experience includes positions with the U.S. Coast Guard in the icebreaker design project the Military Sealift Command and at Newport News Shipbuilding. He is a graduate of N. Y.S. Maritime College and has a MS degree from the University of Michigan. I.F. Glen:received his professional degrees in naval architecture from the Royal Naval Engineering College Manadon Plymouth and RN College Greenwich London entering the Royal Corps of Naval Constructors in 1967. After serving as a Constructor Lieutenant in the Royal Navy's Far East Fleet for a short period he joined the Polaris submarine project team in Bath England in 1968. In 1971 he was seconded to the Canadian Department of National Defense in Ottawa as a Constructor Lieutenant Commander under NATO exchange arrangements where he had responsibilities initially for conventional submarines and latterly for computer aided conceptual design. He ventured to Bath England in 1974 and joined Forward Design Group. In 1975 he took a position as a civilian engineer in the Canadian Defense Department and was Head of Hull Systems Engineering from 1977 to 1979. He joined ARCTEC CANADA LIMITED in 1980 and in addition to managing ice model testing projects and full scale trials has specialized in structural response of ships to ice impact. He headed ARCTEC's Kanata Laboratory from 1981 to 1983 when he was promoted to president. Frederick Seibold:is a research program manager with the Maritime Administration's Office of Advanced Ship Development and Technology. He is responsible for the marine science program which includes research in the areas of ship powering structures and propeller performance and Arctic technology. Mr. Seibold has been employed by Mar Ad since 1961 having hel

This paper describes a multiyear program to make an operational assessment on the feasibility of a year-round Arctic marine transportation system to serve Alaska. Specifically, the three objectives were to: collect meteorological and ice data along potential marine routes; instrument the hull and propulsion machinery to improve design critera for ice-worthy ships; and demonstrate that ships can operate in midwinter Alaskan Arctic ice conditions. The U.S. Coast Guard's Polar class icebreakers were used to make the operational assessment by annually extending the route northward and by operating throughout the winter season. This paper reviews some of the operational and technical achievements to date, as well as plans for future Arctic deployments.

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computer AIDS FOR SHIP DESIGN, INTEGRATION AND CONTROL

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NAVAL ENGINEERS JOURNAL 1980年第2期92卷 73-87页

作者： CARLSON, CM JOHNSON, RA HELMING, FW Mr. Craig M. Carlson received his B.S. degree in Naval Architecture and Marine Engineering from the University of Michigan in 1970 and began his career with the Department of the Navy at the Naval Ship Engineering Center (NAVSEC). In 1972. he returned to the University of Michigan under the NAVSEC Long Term Training Program and received his M.S. degree in Naval Architecture and Marine Engineering. After returning to the Ship Arrangements Branch at NAVSEC. he was assigned as Task Leader for General Arrangements for the PGG PCG PHM. and MCM ship designs and was awarded Outstanding Performance Awards in 1974 and 1975. In addition he was Manager of the Arrangement Subsystem of the Navy's Computer-Aided Ship Design and Construction Program (CASDAC). In October 1979. he became Manager of the CASDAC Hull Design System. Currently. he also is enrolled in the M.S. of Computer Science Program at Johns Hopkins University. Mr. Carlson previously has presented technical papers at ASNE Day 1974 and 1978 as well as at the 1979 DOD Manufacturing Technology Advisory Group Conference. Besides ASNE. which he joined in 1972. he is a member of SNAME. ASE. and the U.S. Naval Institute. Mr. Robert A. Johnson is a Naval Architect in Surface Combatants Design (SEA 03D3). Ship Design Integration Directorate Naval Sea Systems Command. He received an Associate in Engineering degree in Drafting and Design Technology in 1959. his B.S. degree in Aerospace Engineering in 1965. and his M.S. degree in Engineering Mechanics in 1970. all from the Pennsylvania State University. In 1973. he was selected for the NA VSEC Hull Division s Long Term Training Program at the University of Michigan subsequently receiving his M.S.E. degree in Naval Architecture in 1974. Mr. Johnson began his career with the Ordnance Research Laboratory at Pennsylvania State University in 1959 where he worked. on the design of hydroelastic submarine models and conducted research in the area of flow induced structural vibrations. In 1967 he joined HRB-Singer at State Colle

This paper presents an integrated approach to computer-Aided Ship Design for U.S. Navy preliminary and contract design. An integrated Hull Design System (HDS), currently under development by the Hull group of the Naval Sea systems Command (NAVSEA 32). is the vehicle for the discussion. This paper is directed toward practicing ship design professionals and the managers of the ship design process. Primary emphasis of this paper, and of the development effort currently under way, is on aiding ship design professionals in their work. Focus is on integration and management control of the extremely complex set of processes which make up naval ship design. The terminology of the Ship Designer and Design Manager is used. The reader needs no familiarity with the technologies of computer science.

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