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American Control Conference (ACC)

作者： J.M. Santiago M. Jamshidi Air Force Academy Colorado Springs CO USA Laboratory for Computer-Aided Design of Systems and Networks Department of Electrical and Computer Engineering University of New Mexico Albuquerque NM USA Department of Electrical Engineering Air Force Institute of Technology USA

This paper provides some extensions of a powerful open-loop model reduction technique called balanced realization. Developed by Moore, this approach uses concepts of controllability and observability to determine a reduced-order model. Moore's work was developed for controllable, observable, and asymototically stable systems. This paper shows that balancing techniques can be easily extended to unstable systems. Furthermore, using another model reduction method, called chained aggregation, the balanced and chained aggregation methods can be easily combined for systems that are also unobservable and uncontrollable.

关键词： Reduced order systems Symmetric matrices Control systems Matrix decomposition Observability Controllability Force control Eigenvalues and eigenfunctions Laboratories design automation

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A NEW GENERATION OF HIGH-PERFORMANCE PLANING CRAFT

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NAVAL ENGINEERS JOURNAL 1985年第4期97卷 234-247页

作者： JONS, OP KOELBEL, J SHELDON, R Otto Jons:is vice president of engineering at Advanced Marine Enterprises Inc. He received a Diplom Ing. from the Technical University of Hannover W. Germany and an M.S. in naval architecture and marine engineering from the Massachusetts Institute of Technology in 1976. He then joined Litton Ship Systems to work on the DD-963 and LHA programs. He was principal research scientist at Hydronautics and technical director with Designers and Planners before forming in 1976 together with S. Glatz and J. Drewry Advanced Marine where he is responsible for engineering and technical matters on behalf of the corporation. Joseph Koelbel: a senior naval architect at Advanced Marine Enterprises Inc. has for many years specialized in the design of high-speed rough-water boats including a record-setting race boat passenger boats and patrol boats such as the CPIC and the PBM. He received special recognition for his contributions to and editing of the Planing Concept Volume of the Advanced Naval Vehicles Concept Evaluation Study. He is a member of ASNE SNAME (past chairman planing boats panel of the Hydrodynamics Committee) and ABYC. He is the author of a number of published papers on small-craft design. Ray Sheldon:is the head of computer applications at Advanced Marine Enterprises Inc. where he directs activities in computer-aided ship design software development and ship performance prediction. Previously at the Hydronautics Ship Model Basin he was involved in nearly all aspects of ship hydrodynamics and the development and refinement of test methodologies and equipment. Mr. Sheldon is a 1973 graduate of Webb Institute of Naval Architecture (B.S. naval architecture and marine engineering) a member of ASNE and an associate member of SNAME. He is the author of several published papers concerning ship design and experimental methods.

Key aspects of the design development of a capable yet affordable high performance craft are addressed. These aspects include the development of mission requirements, the rationale for major design decisions, performance capabilities, and system and subsystem selection. The superior performance of the design, as demonstrated by an extensive model test program, led to the decision to develop a family of advanced fast patrol boat concepts. Selected family members are also briefly introduced. The paper, furthermore, demonstrates the successful integration of many major computer-aided design (CAD) programs currently in use for U.S. Navy ship design.

关键词： NAVAL VESSELS

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AN INTERACTIVE OPTIMIZATION TECHNIQUE FOR THE NOMINAL design OF INTEGRATED-CIRCUITS

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IEEE TRANSACTIONS ON CIRCUITS AND SYSTEMS 1984年第2期31卷 203-212页

作者： ANTREICH, KJ HUSS, SA Institute of Computer Aided Design Department of Electrical Engineering Technical University Munich Munich Germany Design Center of Integrated Circuits AEG Telefunken Ulm Germany Institute of Computer Aided Design Technical University Munich Munich Germany

The purpose of the paper is to present an approach to the nominal design of integrated circuits by interactive optimization. In solving the nominal design problem, proper values must be assigned to the set of designable parameters of an integrated circuit (IC) such that the requirements of circuit characteristics are fulfilled. The approach is based on a boundary curve of the optimization problem. This boundary curve is used as an assessment criterion to visualize the problem condition and to control the entire optimization process. A standardized representation of the boundary curve suited for graphic terminals is presented as well as an analysis of its characteristics and computational methods for the evaluation of the boundary curve. The approach is demonstrated by an application to a multiple objective design problem of an integrated circuit.

关键词： design optimization Circuit topology Circuit optimization MOSFET circuits Visualization graphics Application specific integrated circuits Circuit simulation design methodology Fluctuations

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A QUANTITATIVE-COMPARATIVE APPROACH TO ANALYSIS OF DISTORTION IN MENTAL MAPS

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PROFESSIONAL GEOGRAPHER 1984年第3期36卷 326-337页

作者： WATERMAN, S GORDON, D STANLEY WATERMAN (Ph.D. in Geography University of Dublin 1969) is Senior Lecturer in Geography at the University of Haifa Haifa 31999 Israel. He has research interests in political and social geography. DAN GORDON (D.Sc. in Mathematics Technion—Israel Institute of Technology—1976) is Lecturer in Computer Studies at the University of Haifa. His research interests include design and analysis of algorithms VLSI computational geometry and computer graphics.

A quantitative procedure for analyzing and comparing distortion in mental maps is presented. Using a microcomputer and digitizer, and by developing a distortion index, comparisons are made by direct analysis of mental maps. A case study of the mental maps of Israel of high school and university students showed a tendency to generalize shape to simple geometric forms, with foreshortening of north-south lines and exaggeration of east-west distances.

关键词： mental maps distortion quantitative analysis comparison

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NC Applications—its Present and Future in Singapore's Industries

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International Journal of Operations & Production Management 1984年第1期4卷 12-17页

作者： Khong Heng Poh Currently Director and Division Manager of Nordskog‐Diethelm Pte Ltd. a company specialising in the manufacture of aluminium and stainless steel products. Graduated in Mechanical Engineering from the University of Manchester Institute of Science and Technology UMIST in 1968. Served an apprenticeship with Aveling‐Barford Ltd. UK. now Special Vehicles Division of British Leyland. Was engaged in research work at UMIST on the application design and testing of NC machine tools. This was sponsored by a machine tool builder and NC systems manufacturer. Awarded a Ph.D degree in Machine Tool Engineering in 1972. Thereafter was appointed Post‐Doctoral Research Fellow and later as Lecturer to continue with the research programme and consultancy work on NC machines in connection with computer‐aided design and manufacture.

The numerically controlled machine tool has become a very topical subject due to the current emphasis on increasing productivity and upgrading of manufacturing industry. This paper reviews the current applications of NC machine tools in Singapore. It also takes a look at the future directions which NC is likely to develop, particularly in the area of computer aided manufacture, and examines the role of the production engineer within this new environment.

关键词： Singapore Machinery computers CAM

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THE NO FRAME CONCEPT - ITS IMPACT ON SHIPYARD COST

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NAVAL ENGINEERS JOURNAL 1984年第3期96卷 218-232页

作者： NAPPI, NS WALZ, RW WIERNICKI, CJ Natale S. Nappi:graduated from City College of New York in 1954 with a B.S. degree in civil engineering and received his M.S. in civil engineering from the Polytechnic Institute of Brooklyn in 1959. He began his professional career in 1954 at the New York Naval Shipyard as a naval architect (structures) performing detail structural design and fabrication studies for CVAs LPDs DDs and CGs and eventually became a supervisory naval architect (structures). From 1965 to 1973 he was a member of the staff of the Computer-Aided Design Division at the David Taylor Naval Ship Research and Development Center (DTNSRDC). As such he was involved in the development of the computer structural design tool the SSDP (in association with Frank M. Lev) and automated detail design programs (CASDOS). His current position is Senior Naval Architect Consultant in the structural integrity group of the Ship Structures Division Structures Department DTNSRDC. Mr. Nappi is the author and co-author of numerous technical papers and reports covering a wide spectrum of topics such as automated structural design process design for producibility and survivability material weight and cost trade-off studies and structural weight determination for high performance ships (i.e. SES SWATH HYSWAS). He has lectured on the subjects of design for survivability and ship structures at the Naval Post Graduate School and MIT. He is a member of ASNE ASCE U.S. Naval Institute Sigma Xi and is a registered Professional Engineer in the State of New York. Mr. Nappi was a member of the NAVSEA working commitee for the computer supported design planning effort and is currently a member of the DTNSRDC ASSET Advisory Committee. Ronald W. Walz:graduated in 1974 from Pennsylvania State University with a B.S. degree in civil engineering. He began his professional career in 1974 at the David Taylor Naval Ship Research and Development Center as a structural engineer in the structural design concepts group of the Ship Structures Division Structures Department.

A proposed cost effective alternative to current U.S. Navy structurally configured hulls is presented in this paper. This proposed design for producibility concept involves the elimination of structural stanchions and transverse web frames. The potential impact of this “no frame” concept on structural design, weight and construction and material costs for naval surface frigates and destroyers is reflected in 1) reduced costs for the installation of distributive systems and 2) a reduced number and complexity of structural details providing a more reliable and less costly structure. This study was performed in three parts: 1) Determine the most feasible length between bulkheads without frames; 2) Using this length perform detail weight studies and construction and material costs analysis comparison on a 72-foot long hull module, with and without frames, for a FFG-7, and 3) Estimate the saving in man hours of labor on the installation of distributive systems and shipfitting for an FFG-7. For the feasible length studies on the “no frame” structural configuration, thirty-seven strength, weight and vertical center of gravity studies were performed on two ship classes; twenty-two on the FFG-7 class and fifteen on the DD-963 class. The detailed weight studies and construction and material cost analyses were conducted for FFG-7 “no frame” and “as built” modules. Results indicating the “no frame” concept module was 6.8% heavier and 14.8% less costly than the “as built” module. For the impact of an FFG-7 “no frame” structurally configured hull on the cost of labor required for the installation of distributive systems and for other functional work such as ship fitting, welding, and electrical, this study indicated a reduction of 169,206 labor hours per ship, representing 7.12% of the total required man hours to fabricate an FFG-7 class ship. With the employment of the “no frame” concept, certain areas of significant concern and potential risk were addressed. These include: 1) t

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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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VARIATIONAL GEOMETRY - A NEW METHOD FOR MODIFYING PART GEOMETRY FOR FINITE-ELEMENT ANALYSIS

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computerS & STRUCTURES 1983年第5-6期17卷 903-909页

作者： LIGHT, RA GOSSARD, DC Computer-aided Design Laboratory Department of Mechanical Engineering Massachusetts Institute of Technology Cambridge MA 02139 U.S.A.

Interactive graphic methods have the potential to significantly reduce the cost associated with pre- and post-processing of finite element analyses. One area of particular importance is the creation and modification of part geometry. This paper describes a powerful method for modification of geometry for finite element analysis pre-processors. The method, called “Variational Geometry”, uses a single representation to describe the entire family of geometries that share a generic shape. A solid geometric model of a component is defined with respect to a set of scalar parameters. Dimensions, such as those which appear on a mechanical drawing, are treated as constraints on the permissible values of these parameters. Constraints on the geometry are expressed as a set of non-linear algebraic equations. The values of the parameters and hence the geometry may be determined by solving the set of non-linear constraint equations. A procedure for minimizing the computational requirements is presented. For a part with n degrees of freedom, the solution time is shown to be O( n ).

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Solid model input through orthographic views 83

Solid model input through orthographic views

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10th Annual Conference on computer graphics and Interactive Techniques, SIGGRAPH 1983

作者： Sakurai, Hiroshi Gossard, David C. Nissan Motor Company Japan Computer Aided Design Laboratory Department of Mechanical Engineering Massachusetts Institute of Technology United States

ISBN: (纸本)0897911091

This paper describes the results of basic studies on procedures for creating solid models of component geometry from two-dimensional orthographic projections. An interactive graphic program was developed to allow the input of three orthographic views of a component geometry by digitizing from a drawing. The views may contain straight lines and circular arcs, solid or dashed. No restrictions are placed on the order or direction of lines and arcs in any view. Using an extension of the Wesley-Markowski procedure, the program constructs a three-dimensional solid model of the object. When the projections are ambiguous, multiple solid models are produced. The solid model may contain planar, cylindrical, conical, spherical and toroidal surfaces. Topological information of the solid model is stored in a winged edge structure. Geometric information is stored as vertex coordinates and surface equations. The procedure for 2D-3D conversion provides a powerful new method for manual input of solid models, a common interface to all turnkey graphics systems, and, properly integrated with existing technology for scanning of drawings, a powerful new method for acquisition of CAD/CAM data bases from existing drawings. The procedure is described, examples of typical input and output are shown, and possible extensions are discussed. . © ACM.

关键词： computer aided design

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THE STRUCTURAL SYNTHESIS design PROGRAM - ITS IMPACT ON THE FLEET

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NAVAL ENGINEERS JOURNAL 1983年第3期95卷 87-99页

作者： WIERNICKI, CJ GOODING, TG NAPPI, NS Mr. Christopher J. Wiernicki:graduated from Vanderbilt University in 1980 with a B.E. degree in Structural Engineering. Upon graduation he began his professional career at the David Taylor Naval Ship Research and Development Center. As a structural engineer in the Surface Ship Structures Division Mr. Wiernicki was responsible for developing improved methods and procedures for designing and evaluating structural systems for surf ace combatants. Specific projects included design for producibility development and evaluation of automated ship structural design methods and participation in the structural design of the CG 49 Cruiser and the current DDG 51 Destroyer. In 1982 Mr. Wiernicki received his M.S. degree in Ocean Engineering from George Washington University. Mr. Wiernicki is a recipient of the SNAME 1982-82 Graduate Scholarship and is currently doing post graduate work in Naval Architecture at Massachusetts Institute of Technology he is a member of ASNE SNAME ASCE and Chi Epsilon. Mr. Thomas G. Gooding:graduated in 1975 from the University of Michigan with B.S. degrees in Oceanography and Naval Architecture. After graduation he began his professional career at the Naval Ship Engineering Center (NA VSEC) as a structural engineer. From 1975 till 1978 Mr. Gooding worked in the area of ship dry docking and was the structural task leader on the complex overhaul ofUSS Long Beach (CGN-9). Mr. Gooding returned to the University of Michigan to receive a M.S. in Naval Architecture in 1979. Currently Mr. Gooding is the structural task leader on the DDGX/DDG 51 program at the Naval Sea Systems Command (NAVSEA). Mr. Gooding is a member of SNAME and the Naval Institute. Mr. Natale S. Nappi:graduated from City College of New York in 1954 with a Bachelor of Civil Engineering and received his M.S. in Civil Engineering from Polytechnic Institute of Brooklyn in 1959. He began his professional career in 1964 at the New York Naval Shipyard as a Naval Architect (Structure) performing detail structural design and fabrication s

The structural design of a ship's section is a complicated, repetitive and time consuming task. With the advent of new technology, high speed computers have enabled the ship designer to accomplish in a matter of seconds what would formerly take days to accomplish by hand. The Structural Synthesis design Program (SSDP) is a N avy developed computer-aided design tool which is used to design (or to analyze) the longitudinal scantlings for a variety of ship cross sections, consisting of any practical combinations of decks, platforms, bulkheads and materials, i.e., various steel and aluminum alloys. The final hull section design will have the lowest practical weight for the chosen geometric configuration, structural arrangements, and imposed loadings. The scantling developed by the program will satisfy all U.S. N avy ship structural design criteria. An explanation of the objective and design elements of N avy ship structures is included. The rationale behind the SSDP design philosophy is developed along with the significant program capabilities. In an attempt to highlight the influence of automated design procedures on the current naval ship design process, the effect of the SSDP on the DDG 51 destroyer structural development is addressed.

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