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MODELING GROUND-WATER QUALITY SAMPLING DECISIONS

GROUND WATER MONITORING AND REMEDIATION 1988年第4期8卷 121-134页

作者： HSUEH, YW RAJAGOPAL, R Ya-Wen Hsueh received undergraduate training in liberal arts at the National Taiwan University and a master's degree in geography with an emphasis in water resources from the University of Iowa. Her major research interests are in the fields of water resources Systems analysis environmental impact assessment and geographic information Systems. Her current affiliation at the National Taiwan University (Department of Environmental Science Taiwan Republic of China) includes research dealing with an assessment of state-of-the-art applications and management of Geographic Information Systems in the Department of Interior of the Government of Taiwan. R. Rajagopal received undergraduate and graduate education in mathematics and statistics from the University of Bombay a master's degree in operations research from the University of Florida and a Ph.D. in resource management with an emphasis on ground water pollution control from the University of Michigan. He is a professor of geography and civil and environmental engineering at the University of Iowa. He is currently a visiting scientist in the Advanced Monitoring Systems Division Environmental Monitoring Systems Laboratory P.O. Box 93478 U.S. Environmental Protection Agency Las Vegas NV 89193.

Questions such as what, where, when, and how often to sample play a central role in the development of monitoring strategies. Limited resources will not permit sampling for many contaminants at the same frequency at all well sites. Therefore, a resource allocation strategy is necessary to arrive at answers for the preceding types of questions. Such a strategy for a ground water quality monitoring program is formulated as an integer programming model (an optimization model). The model will be of use in the process of deciding what constituents to sample and where to sample them so as to maximize a given objective, subject to a set of budget, sampling, and regulatory constraints. The maximization objective in the model is defined as a weighted function of population exposure to a scaled measure of observed chemical concentrations. The sampling constraints are based on the observed variability of contaminants in the aquifer, needed precision in estimates, a chosen level of significance, the available budget for implementing the program, and selected regulatory constraints. The model is tested with field data obtained for 10 selected constituents from more than 650 wells in the Cambrian-Ordovician aquifer in Iowa. Results from two alternative formulations of the model are compared, analyzed, and discussed. Further avenues for research are briefly outlined.

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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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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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File allocation on homogeneous local computer systems with two-level multiaccess networks

File allocation on homogeneous local computer systems with t...

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International Conference on Data engineering

作者： Y.-N. Lien Y.-L. Chang B.W. Wah Department of Computer and Information Science The Ohio State University Columbus OH USA Department of Management and Information Systems University of Arizona Tucson AZ USA Department of Electrical and Computer Engineering and the Coordinated Science Laboratory University of Illinois at Urbana-Champaign Urbana IL USA

Various versions of the file allocation problem on homogeneous two-level local multiaccess networks are examined. The problems associated with file allocation are more simple on two-level networks than on general point-to-point networks because the communication cost for accessing a file is reduced to a three-value variable. File allocation with storage-limit constraints is still NP-hard. The optimal solution, given these conditions, involves transformation into a pure zero-one integer programming problem and a search algorithm based on E. Balas's additive algorithm (1965). In the case in which the system is dominated by the communication cost, the simple file allocation problem is polynomially solvable. An efficient heuristic algorithm with guaranteed performance is proposed for this special case.< >

关键词： Computer networks Financial advantage program Costs Distributed computing Distributed control Information processing Educational institutions Memory Polynomials Heuristic algorithms

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IMPROVED LOGISTICS SUPPORT THROUGH STANDARDIZATION

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NAVAL ENGINEERS JOURNAL 1988年第2期100卷 40-46页

作者： KINNEY, ET CONSTANT, AE Edward T. Kinney:is presently director of the Machinery Group Naval Sea Systems Command (NavSea). He graduated from Michigan State University in 1952 and joined the Bureau of Ships Engineer-In-Training Program. Mr. Kinney has held a variety of technical and senior management positions in NavSea and the Naval Material Command. He has authored a number of technical articles and papers and has been a contributing author to the Naval Engineers Journal. He is a past president of the Association of Scientists and Engineers and holds membership in ASNE SNAME Federal Conference of Environmental Engineers and ASME and is chairman of the ASME Shipbuilding Standards Machinery Committee. Alexander E. Constant:is a native of Newport Rhode Island and a graduate of Pennsylvania Military College from which he received his BS degree in civil engineering in 1960. After two years with the U.S. Forest Service working in civil sanitary engineering designing recreational facilities he joined the Vermont Water Resources Department as a project engineer. He was recruited by the Navy in 1966 and he accepted a position in the Piping Systems Branch where he attained the position of director. At present he is head of the Auxiliary Equipment Division Naval Sea Systems Command where for the past six years he has been responsible for the design operation maintenance and life cycle support for the majority of the U.S. Navy's shipboard auxiliary equipment. He has been a member of U.S. and international committees on standardization and has been a delegate representing the U.S. at several meetings throughout the world.

This paper presents improvements in logistics support of hull, mechanical, and electrical (HM&E) components through standardization to the piece part level. The process of component standardization is outlined and compared with traditional HM&E acquisition approaches. The impact of standardization on logistics support is presented with case examples cited to graphically demonstrate how logistics improvements are derived. The paper also presents standardization costs and benefit analyses. A compelling case for increased HM&E standardization efforts is made from a logistics improvement perspective.

关键词： NAVAL VESSELS

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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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SIMPLIFICATION OF GAS-TURBINE INTAKE ANTI-ICE systems

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NAVAL ENGINEERS JOURNAL 1988年第1期100卷 45-52页

作者： EXELL, JR KILLINGER, A LCdr. John R. Excell: USN received a bachelor of architecture from the University of Michigan and a master of science degree in mechanical engineering from the U. S. Navy Postgraduate School. He was commissioned in 1973 serving first as damage control assistant aboard USSGuadalcanal(LPH-7) and later as commissioning main propulsion assistant on USSMerrill(DD-976). He became an engineering duty officer in 1979 and served at Norfolk Naval Shipyard as senior ship superintendent for six ships and later within the shipyard Design Department. In May 1984 LCdr. Exell was assigned to the DD-963 Class Special Projects Office as program manager for air system improvements including the bleed air and anti-ice systems. He recently completed the Defense Systems Management College Ft. Belvoir VA and returned to NavSea PMS 377 as deputy for strategic sealift programs. Arthur Killinger:graduated from the University of Maryland in 1968 with a bachelor of science degree in mechanical engineering. He joined MPR Associates Inc. working on submarine safety design reviews following the loss of USSScorpion(SSN 589). After two years in the U.S. Army Nuclear Reactor Program and a year as U.S. Army engineer maintenance advisor in the Republic of Vietnam he returned to MPR Associates Inc. in 1972. Since then he has worked on nuclear power plant projects for several electric utilities as well as submarine and surface ship overhaul and maintenance improvement programs for the U.S. Navy. Mr. Killinger is a member of the American Society of Naval Engineers and the American Society of Mechanical Engineers.

This paper describes the steps taken to simplify the gas turbine intake anti-ice systems on DD-963 and DDG-993 class ships. The anti-ice system was designed and built as fully-automatic protection against intake duct icing on main propulsion turbines and electric generator turbines. Operating experience with the system indicated that it was nonfunctional more than 60% of the time. The system's poor availability was caused by its complexity, lack of use, lack of spare parts, poor training and documentation, and design and material problems. A Navy Independent Design Review Team (IDRT) reexamined the technical bases for installing an automatic anti-ice system and demonstrated that automatic control was not necessary for gas turbine intake duct anti-icing. A series of design review calculations and shipboard tests confirmed that anti-icing protection could be provided by manual control of installed butterfly valves feeding hot air to each turbine intake. The time from the IDRT design simplification recommendations to the first modification of the anti-ice system was less than one year. To date, half of the 30 of the 35 ships in the two classes have been modified. This system simplification will result in life cycle maintenance cost savings in excess of 13 million dollars. Future CG-47 class and DDG-51 class ships will include this simplified approach to anti-ice system design for gas turbine intakes.

关键词： GAS TURBINES

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NTDS - A PAGE IN NAVAL HISTORY

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NAVAL ENGINEERS JOURNAL 1988年第3期100卷 53-61页

作者： SWENSON, EN MAHINSKE, EB STOUTENBURGH, JS Capt. Erick N. Swenson USNR (Ret.):is a project manager for special projects in the Surface Ship Systems Division Hughes Aircraft Company Fullerton Calif where he has been employed since his retirement from the U.S. Navy in 1975. Originally trained as an electronics technician during WWII in the Captain Eddy program he later received a BS degree in electrical engineering from the University of Rochester Rochester N. Y. in 1950. Subsequent engineering education was received at the University of Pittsburgh Pittsburgh Penn. and the Naval Postgraduate School Monterey Calif. After commissioning he was ordered to duty as the electronics division officer on the USSMissouri(BB-63) and electronics ships superintendent at Hunters Point Naval Shipyard San Francisco Calif. When the design of the Naval Tactical Data System began in the mid-1950s Lt. (j.g.) Swenson was ordered to the Bureau of Ships Navy Department Washington D.C. as the junior engineering duty only officer assigned to the project. From 1962 to 1965 LCdr. Swenson was assigned as the BuShips technical representative on the program at Remington Rand Univac St. Paul Minn. For the next ten years he returned to BuShips/NavSea/NAVSEC as the NTDS project officer. During this time the project expanded considerably foreign military sales were heavily involved and interoperability with other services and countries were established. His final effort on active duty was to instigate the redesign of the previousSpruanceclass destroyers into the newerAdmiral Kiddclass improvement program. He is a registered professional electrical engineer in the State of California listed inWho's Who in the Worldis a life member of ASNE and chairman of the Long Beach/Greater LA Section. Capt. Edmund B. Mahinske USN (Ret.):is an alumnus of the U.S. Naval Academy the Massachusetts Institute of Technology and the Harvard Business School. His technical background is in electronics and he specialized in the management of programs involving the application of comp

A little over thirty years ago, a group of naval engineers were assembled by the Bureau of Ships to develop a new system approach to the combat information center (CIC). The CIC of World War II, with its “grease pencil” plots and voice telling of tactical information from sensors and other ships, could no longer provide the timely, coordinated reaction to postwar threats. This project group led the Navy into the new world of large-scale, high-speed digital electronics and into a new mode of conducting naval warfare as well. There were no off-the-shelf computers of the requisite capability, size and reliability; what were available were monstrous vacuum tube computers. There were no display equipments that were “conversant” in both the digital language of the computer and the analog language of the sensors and the weapon systems. Who ever heard, at that time, of a computer running a tactical communication net automatically? It was hard enough to find sufficient numbers of engineers who knew what a digital computer was. This paper, by three naval engineers in the implementing engineering office, depicts the evolvement of the Naval Tactical Data systems (NTDS) as they saw it. It discusses the problems that stemmed from the transition from the old world of analog into the new digital world, the system concepts that steered the development; the key decisions that were made; new electronic equipment and processes that became necessary; and the need of the mangagement to face the real world of deadlines, ship schedules and operational requirements.

关键词： NAVAL WARFARE

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AUXILIARY SHIP HULL FORM DESIGN AND RESISTANCE PREDICTION

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NAVAL ENGINEERS JOURNAL 1988年第3期100卷 275-292页

作者： FUNG, SC The author is a naval architect with the Preliminary Design Division of the Naval Sea Systems Command. Mr. Fung graduated from National Cheng Kung University in 1976 and Stevens Institute of Technology in 1977 from which he received his B.S. degree in naval architecture and marine engineering and M.S. degree in ocean engineering respectively. He started his career with M. Rosenblatt and Son in 1979 and became a senior naval architect with the Hull Form & Hydrodynamics Department in Designers and Planners in 1981. For the past ten years Mr. Fung has performed a variety of tasks in the area of feasibility study hydrodynamic design including advanced marine vehicles bulbous bows and hull form design for surface combatant and non-combatant ships. Currently he is a project naval architect for the T-AO twin skeg integrated hull design and the AE-36 Energy Enhancement Program. Mr. Fung is a member of ASE ASNE and SNAME. He received the John C. Niedermair A ward in 1984 and 1986 for the best paper presented at the ASE annual technical symposiums.

In this paper 154 auxiliary type monohull designs are analyzed for guidance on how to select the appropriate hull form parameters, particularly with regard to the effects of hull section shapes, sectional area and design waterline curves on ship resistance. This paper also discusses the resistance predictions based on (1) the statistical approach and (2) the use of series model test data (such as Taylor's standard series) and associated “worm curve factors” with the help of data management software.

关键词： SHIPS

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THE REVERSE engineering PROCESS - A COMPETITION engineering PERSPECTIVE

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NAVAL ENGINEERS JOURNAL 1988年第2期100卷 47-53页

作者： DIMASCIO, AJ MIXON, CO Dr. A.J. Di Mascio:is currently a senior program manager for VSE Corporation of Alexandria Va. Prior to joining VSE he was a career civil servant in the Department of the Navy (retired in May 1986). His last two assignments were director Office of Naval Acquisition Support and deputy commander of the Naval Air Systems Command. He has a doctorate degree from George Washington University and B.S. and M.S. degrees from Drexel Institute of Technology. Capt. Cameron O. Mixon USN (Ret.):was graduated from the Georgia Institute of Technology in 1950 and was subsequently commissioned and entered active naval service. During World War II he entered the Navy as an apprentice seaman and was discharged after the war ended as a chief petty officer (motor machinist diesel). As a commissioned officer he served aboard the USS Walker (DD-517) as engineer officer. In 1955 he was designated an engineering duty officer after which he served on the COMMINELANT Staff then as repair officer aboard the USS Yellowstone (AD-27). He had tours of duty at SRF Yokosuka Charleston and Long Beach Naval Shipyards and in the Vietnamese Naval Shipyard in Saigon as the senior naval advisor. His last tour prior to retirement was as senior machinery inspector on the INSURVBoard Washington D.C. He is currently employed by VSE Corporation where he has been active in the areas of breakout and reverse engineering.

Reverse engineering can be a powerful tool in the development of a competitive technical data package. However, it should be incorporated as one subset of the several tools available in a comprehensive competition engineering program. There are several technical programmatic, and economic factors which must be considered within the overall system context of such a competition engineering framework prior to committing to implementation of reverse engineering. This paper presents an overview of some of the principal technical, management and economic considerations which should be factored into the planning, decision-making, and control processes when applying reverse engineering techniques to a Replenishment Spares Breakout program. A decision-making model and process management descriptive model are presented as guides to planning and control.

关键词： MILITARY engineering

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