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ON EVALUATING BOOLEAN FUNCTIONS WITH UNRELIABLE TESTS

International Journal of Foundations of computer Science 1990年第1期1卷 1-10页

作者： CLAIRE KENYON ANDREW C. YAO DIMACS Center Rutgers University Piscataway NJ 08855 USA Ecole Normale Supérieure 45 rue d’Ulm 75230 Paris Cedex 05 France Research supported by the graduate exchange program between Ecole Normale Supérieure and Princeton University. Computer Science Dept Princeton University Princeton NJ 08544 USA Research supported in part by NSF under grants DCR83–08109 and CCR-8813283.

We consider the problem of evaluating a boolean function P(x 1 ,…,x n ), by asking queries of the form “x i =?”, and receiving answers which may not always be truthful. Assuming that the total number of lies does not exceed E, we present an algorithm with cost O(n+s P E+t P E), where s P is the maximal size of a minterm of P(x) and t P ‘is the maximal size of a maxterm. We also prove that if P is monotone, then any algorithm for evaluating P must ask Ω(s P E+t P E) queries for some input.

关键词： algorithms boolean functions error correction lower bounds unreliable tests

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AEGIS DISPLAY SYSTEM MAP DATA-BASE

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NAVAL ENGINEERS JOURNAL 1990年第3期102卷 138-145页

作者： PANTAZOPOULOS, MV BARKER, RG SLIMMER, RL Michael V. Pantazopoulos:has been a physicist at the Naval Surface Warfare Center in Dahlgren Va. since August 1985. He received his B.S. and M.S. in physics from Emory University. He has been a member of the Aegis Display System Group in the Aegis Combat Direction Systems Branch since 1985. This group maintains the Aegis coastline map data base and most of his work has been in the developing analyzing and testing of the digital map data bases. R. Gordon Barker:has been a mathematician at the Naval Surface Warfare Center in Dahlgren Va. since 1964. He received a B.S. from the University of Virginia and did his graduate study at Princeton University. He has been a member of the Aegis Display System Group since 1982. During the development of the Mark 1 Aegis Display System Map Data Base Mr. Barker wrote the program to perform the “data thinning” of the map data. In order to support the system upgrades in progress Mr. Barker developed a tool to polygonize the map data. Rebecca L. Slimmer:has been a computer scientist at the Naval Surface Warfare Center in Dahlgren Va. since 1984. She received her B.S. from Sam Houston State University. She has been a member of the Aegis Display System Group since 1984. Her work has included maintaining and upgrading the Aegis Display System Map Data Base Generation Computer Program participation in Defense Mapping Agency data base evaluations and development of a map data base for the Naval Intelligence Processing System in a joint effort with M. Pantazopoulos. She currently serves as the point of contact for the Aegis Display System Map Data Base.

The Aegis Combat System is an advanced integrated combat system engineered specifically for Ticonderoga class cruisers. An essential component of this system is the Aegis Display System (ADS), which displays real-time ownship and fleet tactical information. Integral to the ADS is the display of coastline map data to provide geographic perspective to the tactical picture. The purpose of this paper is to describe the design and implementation of the map data base into the ADS. The original ADS equipment limited the number of coastline points which could be displayed at one time, thus leading to the development of several data thinning techniques. The requirements for real-time maps also motivated the introduction of some novel features into the data base architecture. The data base was required to support nine range scales and yet maintain the same approximate density of points throughout the entire world. To accomplish this, the data were partitioned into “windows,” with a uniform size based on distance rather than an angular measurement. This resulted in windows approximately the same size in area, but with a longitudinal width which increases as polar latitudes are approached. The number of data points was then reduced by applying several thinning algorithms so that the desired point densities were reached. The windows were organized into four separate data subbases, each with a different window size but a similar point density. This scheme allows coverage of an entire display area with at most four windows at any range scale. The display speed was optimized by exploiting the Aegis Combat System's use of orthographic projection from the earth's surface to the display plane. This type of projection permits integer arithmetic in the transformation projection equations when the data points are stored as X,Y,Z earth-centered coordinates instead of as latitude and longitude. This results in substantially faster map processing and display times, thereby allowing the ADS

关键词： Display Devices

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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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Note on development of modularity in simple cortical models 89

Note on development of modularity in simple cortical models

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Proceedings of the 2nd International Conference on Neural Information Processing Systems

作者： Alex Chernjavsky John Moody Molecular and Cellular Physiology Beckman Center Stanford University Stanford CA and Neuroscience Graduate Program Section of Molecular Neurobiology Howard Hughes Medical Institute Yale University Yale Computer Science New Haven CT

The existence of modularity in the organization of nervous systems (e.g. cortical columns and olfactory glomeruli) is well known. We show that localized activity patterns in a layer of cells, collective excitations, can induce the formation of modular structures in the anatomical connections via a Hebbian learning mechanism. The networks are spatially homogeneous before learning, but the spontaneous emergence of localized collective excitations and subsequently modularity in the connection patterns breaks translational symmetry. This spontaneous symmetry breaking phenomenon is similar to those which drive pattern formation in reaction-diffusion systems. We have identified requirements on the patterns of lateral connections and on the gains of internal units which are essential for the development of modularity. These essential requirements will most likely remain operative when more complicated (and biologically realistic) models are considered.

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Is American Energy Politics Ideological?

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The Energy Journal 1989年第1期10卷 55 - 76页

作者： Eric M. Uslaner * Department of Government and Politics University of Maryland College Park. Support from the General Research Board of the Graduate School University of Maryland College Park the College of Behavioral and Social Sciences University of Maryland College Park the Computer Science Center of the University of Maryland College Park and the Everett McKinley Dirksen Congressional Leadership Research Center is greatly appreciated as are the comments of John E. Chubb M. Margaret Conway Pietro Nivola Karol Sollan Charles Stewart III Peter Van Doren and the editor and anonymous reviews of this journal. I also appreciate the research assistance of Rodger Payne. Kevin Ogrady provided assistance on the unfolding program while Mike Wagner was (as always) more than invaluable. I am particularly indebted to the representatives of energy interest groups who kindly gave of their time for my interviewing. This paper draws from and expands upon Uslaner (1989 ch. 5).

When we think of energy issues, we generally conjure up ideas of conflicts between producers and consumers. These translate into visions of grand ideological conflicts between the left and the right. Wildavsky and Tennenbaum (1981) speak of battles between "preservationists" and "industrialists." Kalt (1981) argues that "[tihe domestic energy 'crisis' is, far more than anything else, a quarrel over income distribution." Ideological straight fights are marked by a single dimension of conflict. In particular, ideological politics, as opposed to religious or ethnic cleavages, suggests a battle between left and right--or, producers and consumers in the case of energy battles. When there are only two contestants, one is sure to win if the group decision is made by majority rule. Even in the United States Congress, where complex rules often frustrate coherent policy formation, strongly-held positions can prevail over obstructionists if they are determined enough. Yet, during the 1970s many attempts to form a "national energy policy" failed. In the 1980s Congress again stumbled in making natural gas policy as it defeated both decontrol and recontrol proposals.

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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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ON SOME RECENT EVOLUTIONS IN PERSONAL SUPERCOMPUTING AND WORKSTATION GRAPHICS

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COMMUNICATIONS IN APPLIED NUMERICAL METHODS 1988年第3期4卷 373-378页

作者： HAJJAR, JF MARTHA, LF OCONNOR, TF ABEL, JF Program of Computer Graphics Cornell University Ithaca NY 14853 U.S.A. Graduate Research Assistant Department of Structural Engineering. Graduate Student Department of Structural Engineering. Visualization Engineer/Technical Specialist. Professor of Structural Engineering.

Recent hardware advances for both enhanced computing and interactive graphics are used to improve the effectiveness of three-dimensional engineering simulations. The two examples presented, drawn from structural engin... 详细信息

关键词： computers, Personal

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DATA MULTIPLEX SYSTEM (DMS) - ASPECTS OF FLEET INTRODUCTION

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NAVAL ENGINEERS JOURNAL 1988年第6期100卷 41-47页

作者： BLACKWELL, LM Luther M. Blackwell:is presently the Data Multiplex System (DMS) program manager in the Bridge Control Monitoring and Information Transfer Branch of the Naval Sea Systems Command (NavSea). He graduated from the University of Maryland in 1964 receiving his BS degree in electrical engineering. After graduating he was employed in the Bureau of Ships where he held project engineering assignments on various ships entertainment magnetic tape recording fiber optics computer mass memory and information transfer systems. He has also pursued graduate studies in engineering management at The George Washington University.

The Data Multiplex System (DMS) is a general-purpose information transfer system directed toward fulfilling the internal data intercommunication requirements of a variety of naval combatant ships and submarines in the 1990–2000 time frame. The need for a modern data transfer system of the size and capability of DMS has increased as various digital control systems throughout naval ships have adopted distributed processing architectures and reconfigurable control consoles, and as the quantity of remotely sensed and controlled equipment throughout the ship has increased manyfold over what it was in past designs. Instead of miles of unique cabling that must be specifically designed for each ship, DMS will meet information transfer needs with general-purpose multiplex cable that will be installed according to a standard plan that does not vary with changes to the ship's electronics suite. Perhaps the greatest impact of DMS will be the decoupling of ship subsystems from each other and from the ship. Standard multiplex interfaces will avoid the cost and delay of modifying subsystems to make them compatible. The ability to wire a new ship according to a standard multiplex cable plan, long before the ship subsystems are fully defined, will free both the ship and the subsystems to develop at their own pace, will allow compression of the development schedules, and will provide ships with more advanced subsystems. This paper describes the DMS system as it is currently being introduced into the fleet by the U.S. Navy. The results of its design and implementation in the DDG-51 and LHD-1 class ships are also presented.

关键词： Multiplexing Equipment

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Heuristic assignments of redundant software versions and processors in fault-tolerant computer systems for maximum reliability

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Probability in the Engineering and Informational Sciences 1987年第4期1卷 457-479页

作者： Kar Leow, Soo Mcallister, David F. Graduate Program in Operations Research North Carolina State University RaleighNC27695 United States Department of Computer Science North Carolina State University RaleighNC27695 United States

We address the problem of assigning multiple copies of n independently developed versions of a program to a set of m(m > n) possibly heterogeneous processors to maximize system reliability. This problem is viewed as a partition and assignment problem. We first partition the set of processors into n clusters or subgroups. A program version is then assigned to be executed on all the processors in the cluster. This means that each processor in the cluster will execute a copy of the assigned version. The cluster's unreliability is the probability of failure of all its processors. Component i of this system is composed of the copies of version i and the assigned cluster of processors. Copyright © Cambridge University Press 1987.

关键词： Combinatorial optimization

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GENERAL ARRANGEMENT DESIGN computer-SYSTEM AND METHODOLOGY .1. GENERAL ARRANGEMENT DESIGN SYSTEM

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NAVAL ENGINEERS JOURNAL 1987年第3期99卷 261-273页

作者： CARLSON, CM FIREMAN, H Craig M. Carlson:is a general engineer in the Computer Aided Engineering Division (SEA-507). He received his B.S. degree in naval architecture from the University of Michigan in 1970. In 1972 he was selected for the NAVSEC Hull Division's Long Term Training Program at the University of Michigan and received his M. S. E. degree in naval architecture in 1973. Additionally he has done graduate work in computer science at The Johns Hopkins University. Mr. Carlson began his career with the Naval Ship Engineering Center in 1970 where he worked in the Ship Arrangements Branch. While in ship arrangements he was task leader for the PGG PCG PHM and MCM ship designs. In addition he was project engineer for shipboard stowage ship space classification system and ship standard nomenclature. He was technical manager of the CASDAC arrangement subsystem and the CASDAC hull design system. In 1982 he joined what is now the Computer Aided Engineering Division. Currently he is the manager for the computer supported design version XX system. Besides ASNE which he joined in 1972 he is a member of SNA ME and the U.S. Naval Institute. Howard Fireman:is a naval architect in the Ship Arrangements Design Division (SEA-55W1). He received his B. S. E. degree in naval architecture from the University of Michigan in 1979. In 1983 he was selected for NavSea's Long Term Training Program at the University of Michigan and received his M. S. E. degree in naval architecture with a specialization in ship production and computer aided ship design in 1985. Mr. Fireman began his career with the Naval Ship Engineering Center in 1977 as an engineering cooperative student. Since graduating from the NavSea EIT program he has worked in the Ship Arrangements Design Division. He was task leader for the AOE-6 AE-36 T-AH ARS-SO and SWATH T-AGOS ship designs. He is technical manager of the CSD General Arrangement Design System and is currently the Hull Group CSD coordinator. Besides ASNE which he joined in 1979 he is a member of SNA ME ASE a

The ever increasing complexity of ships coupled with cost, schedule, and resource constraints require innovative methods by the Naval Sea Systems Command's ship design community to meet this challenge. This paper describes the effort by the NavSea Ship Arrangement Design Division to dramatically improve its ship design capability by the use of a system of computer-based design tools called the General Arrangement Design System. The General Arrangement Design System (GADS) is based on the engineering requirements of the ship arrangement design process. GADS is currently being used as a production engineering tool. This paper is organized into two parts. Part I describes the General Arrangement Design System, and Part II describes the general arrangement design methodology.

关键词： NAVAL ARCHITECTURE

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