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Achievement of essentially full spatial coherence in a high-average-power soft-x-ray laser

Physical Review A 2001年第3期63卷 033802-033802页

作者： Y. Liu M. Seminario F. G. Tomasel C. Chang J. J. Rocca D. T. Attwood Applied Science and Technology Graduate Program University of California Berkeley California 94720 Center for X-ray Optics Lawrence Berkeley National Laboratory Berkeley California 94720 Department of Electrical and Computer Engineering Colorado State University Fort Collins Colorado 80523 Department of Electrical Engineering and Computer Science University of California Berkeley California 94720

We report an observation of essentially full spatial coherence in a high average power soft-x-ray laser. Rapid coherence buildup due to strong refractive antiguiding in a long plasma column is experimentally demonstrated. This allows the generation of fully coherent, milliwatt-level average power soft-x-ray radiation by a tabletop device. The peak brightness of this laser reaches 2×1025photonss−1mm−2mrad−2 within 0.01% spectral bandwidth, making it one of the brightest soft-x-ray sources available.

关键词： .full spatial high average coherence buildup plasma column degree of spatial

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Fuzzy Bayes predictor in electric load forecasting

Fuzzy Bayes predictor in electric load forecasting

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International Joint Conference on Neural Networks (IJCNN)

作者： M.A. Teixeira G. Zaverucha V.N.A.L. da Silva G.F. Ribeiro Systems Engineering and Computer Science Program Graduate Programs in Engineering COPPE Federal University of Rio de Janeiro Brazil Electric Power Research Center CEPEL CEPEL Brazil

ISBN: (纸本)0780370449

We present the fuzzy Bayes predictor (FBP), a hybrid system for the task of monthly electric load forecasting. The FBP is a modification we introduce in the naive Bayes classifier in order to enable it to predict numerical values. We consider three versions of the FBP, each one with a different dependence among the input data: independence, first-order and second-order dependence. For verifying the efficiency of the FBP's prediction, we compare it with two fuzzy systems and two traditional forecasting methods, Box-Jenkins and Winters exponential smoothing.

关键词： Load forecasting Fuzzy systems Power engineering and energy Smoothing methods Testing Niobium compounds Systems engineering and theory computer science Predictive models Electric variables measurement

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Recurrent neural gas in electric load forecasting

Recurrent neural gas in electric load forecasting

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International Joint Conference on Neural Networks (IJCNN)

作者： M.A. Teixeira G. Zaverucha V.N.A.L. da Silva G.F. Ribeiro Systems Engineering and Computer Science Program-Graduate Programs in Engineering Federal University of Rio de Janeiro Brazil Electric Power Research Center Brazil

We have proposed for the task of hourly electric load forecasting a hybrid neural system combining unsupervised and supervised learning. The system consists of a recurrent neural gas (RNG) network and many Elman neural networks (ENs). RNG is a modification we introduced in the neural gas (NG) network in order to enable it to do clustering using a sequence of input data. For verifying the RNG's performance, many architectures are compared in the learning of global and local models. In a global model only one supervised network is trained and in a local model the training examples are grouped by a clustering algorithm and each one of these groups is sent to different supervised networks. These architectures use different clustering algorithms (NG and RNG) or different supervised networks for prediction (ENs that are trained by backpropagation or backpropagation through time, and feedforward networks).

关键词： Load forecasting Clustering algorithms Neural networks Predictive models Power engineering and energy Backpropagation algorithms Supervised learning Systems engineering and theory computer science Recurrent neural networks

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Modelling combat system manning and manpower reduction

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NAVAL ENGINEERS JOURNAL 1999年第3期111卷 153-171页

作者： Roos, CH Carl H. Roos:is a Senior Engineer with Logicon-Syscon. A graduate of the University of Pittsburgh with a BSEE degree he has over 35 years experience in functional operational combat system fire control interface and computer program design. As technology changed and the combat system was upgraded Mr. Roos maintained his level of technical expertise by taking graduate-level courses in computer science modelling & structured analysis networking & fiber optics. He has worked in various capacities on the LHD LHA DDG 993 DD 963 LPD 17 LCC LPD 13 CGN 38 CGN 9 CG 26 and the DDG Class Combat Systems. In recent years Mr. Roos has been responsible for managing directing and performing engineering design and analysis efforts associated with Battle Management Organization (BMO) functional analysis and operational analysis. These efforts were used in defining combat system operational requirements shipboard space requirements and integration requirements. His paper “Configuration Management of Digital Programs” was published at the 1972 IEEE Southeastern Conrence.

NAVSEA 03K41 is responsible for generating Combat System Rattle Management Organizations (BMO) and Functional Flow Diagrams (FFD). Several years ago, NAVSEA provided the resources to conduct a functional analysis that would support the development and validation of the BMOs and FFDs. The major obstacle in performing the analysis was obtaining a consensus on how the functional hierarchy was to be structured. The non-optimum organization of the hierarchy was selected;as a result, the functions were difficult to define, find, use, and validate. Recognizing the shortcomings of this effort, research was conducted to evaluate state-of-the-art structured modelling techniques, concepts, and methodologies. Two modelling concepts by James Martin were found to be applicable for the combat system functional analysis: Enterprise Modelling Concept and Functional Decomposition Modelling Concept. The Structure Modelling definitions of Whitten, Bently, and Barlow provided the guidelines for using the Martin concepts. During the ensuing BMO and FFD development efforts, a Ship's Combat System (SCS) Modelling concept evolved and a SCS Model was developed. This paper addresses how the modelling concepts and tools are used in the BMO and FFD development and validation process. Data from the SCS Model provides the basis for defining combat system requirements (e.g., software, data display, database, networking, etc.).

关键词： Naval vessels

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Applying fuzzy functions and sequential coordination to optimization of machinery arrangement and pipe routing

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NAVAL ENGINEERS JOURNAL 1998年第6期110卷 43-54页

作者： Wu, BC Young, GS Schmidt, W Choppella, K Dr. Bi-Chu Wu:received a PhD in Mechanical Engineering from the University of Maryland College Park in 1991. She has worked on projects involving naval architecture design optimization solid mechanics and database development. Presently a senwr engineer with Angle Incorporated Dr Wu's research interests are in design optimization and fuzzy logic applications. Dr. Gin-Shu Young: a senior engineer with Angle Incorporated holds a PhD in Mechanical Engineering from the University of Maryland College Park. As a guest researcher with National Institute of Standards and Technologies from 1990 to 1993 he worked on vision-based navigation for autonomous vehicles. His experience also includes applications of optimization fuzzy logic neural network and genetic algorithm methods to engineering system design Mr. William Schmidt:co-founded Angle Incorporated in 1990 and has served as Vice PresidentlChiefScientist during this tame. He holds a B.Sc. in Applied Science from the Naval Acadt?my and an M.Sc. in Physics from the Naval Post Graduate School. He has cner 20 years experience in technical leadership material and personnel management. He has led the application of computer aided design (CAD) and Product Model Information Exchange to the shipbuilding industry. His experience also includes leading the amlication of model based operational analysis to support the Live Fire Test Program for DDG 51 Class Destroyers. Mr. Krishna M. Choppella:is a Sofware Engineer at Eidea Laboratories Incotporated where he works on componentbased distributed enterpvise frameworks. He has been involved in creating data analysis tools for the US Nay by integrating CAD modeis databases and graphical front ends. His work in the Masters degree program in Mechanical Engineering at the University of Texas at Austin was in di0ddase.r spectroscopy of combustion products in porous-matri burners. He received his Bachelors degree in Electrical Engineering in India. He was a Research Associate at the Centre for Laser Technology and Project Engi

Ship design is often multidisciplinary involving several design elements with various types of objectives and constraints (O/C) some easily described as mathematical formulas, others better modeled as descriptive assertions. This paper describes a method based on fuzzy functions and an integrated performance index to model O/C using descriptive assertions to be used with mathematical formulas in optimization. Another issue addressed in this paper concerns the coordination of design elements when sequentially coupled, that is, when one leads the other and the performance of the follower depends greatly on the design of the leader. Based on neuro-fuzzy techniques, the method described here coordinates and optimizes sequentially coupled elements. The two methods are applied to machinery arrangement (MA) and pipe routing (PR). Preliminary models for optimization of MA and PR are described considering convenience, producibility: engine room size, interference and location as factors in the O/C set. Some test results from MA/PR applications are presented and discussed. The methods are generic and can be extended to other elements in ship design. They are mutually independent and may be used separately Two advantages of their use are an improvement in overall performance and a reduction in the need for redesign of elements.

关键词： Optimization

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Analysis of product codes for frequency-hopped spread-spectrum with partial band interference

Analysis of product codes for frequency-hopped spread-spectr...

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MILCOM, Military Communications Conference

作者： T.C. Nolan W.E. Stark Department of Defense graduate fellowship program Focused Research Initiative agreement Ann Arbor MI USA Department of Electrical Engineering and Computer Science University of Michigan Ann Arbor MI USA

A jamming game is considered. A transmitter encodes the data, in a product code (PC), and transmits it in a slow frequency-hopped spread-spectrum (FHSS) system. A hostile jammer attempts to block correct packet reception by adjusting the fraction of the total band in which it distributes the jam power, /spl rho/. Two cases are considered. In the first case, the transmitter declares his strategy and the jammer uses this information to select his best jamming fraction. In the second case, the jammer declares his strategy first and the transmitter uses this information to select his best rates. Results are obtained using asymptotic analysis of a product code using singly extended Reed-Solomon (RS) row and column codes whose size grows large. This asymptotic analysis leads to good choices of the row and column rates for the PC in both cases.

关键词： Product codes Spread spectrum communication Interference Jamming Decoding Error correction codes Frequency shift keying Error correction Reed-Solomon codes Transmitters

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Empirical testing: The prototyper's evaluation mechanism

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NAVAL ENGINEERS JOURNAL 1997年第1期109卷 41-46页

作者： Hafner, AN Arnold N. Hafner Ph.D.:is founder and president of Information Systems Research (ISR). He has twenty-five years of experience in systems development and is published in the field of systems development management. He served as corporate research scientist at Systems Exploration Inc. from 1988 to 1991 program director at Computer Science Corporation from 1983 to 1988 director of operations at Republic Management Systems Corporation from 1981 to 1983 and program manager at Computer Science Corporation from 1972 to 1981. A 1962 graduate of the US. Naval Academy he holds a doctoral degree in human behavior and engineering degrees in electronics and communications. He has taught courses on information systems and systems management at most of the colleges in the San Diego area. Dr. Hafner has presented fourteen refereed research papers while publishing sixteen articles and a book A Manager's Guide to Software System Development.

Evaluating complex systems is the subject of this paper, the third in a series investigating prototyping. It provides an interesting and helpful overview of how to evaluate systems prototypes and outlines the iterative stream of developer-user interactions that is replacing older approaches to testing and evaluating new military systems, which promise to reduce the time required to develop and field future military capabilities. Changes to the acquisition process, such as those the paper sketches, will facilitate the nation's rapid transit through its current revolution in military affairs.

关键词： Systems analysis

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Influence of human engineering on manning levels and human performance on ships

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NAVAL ENGINEERS JOURNAL 1997年第5期109卷 67-76页

作者： Anderson, DE Oberman, FR Malone, TB Baker, CC David E. Anderson:has a bachelor of science degree in environmental engineering from Florida Technological University and a master's degree in environmental engineering from the University of Central Florida. He is a graduate of the Naval Sea Systems Command's Engineer-In-Training (EIT) Program. Mr. Anderson was instrumental in introducing the collective protection system (CPS) in the U.S. Navy developing the initial forward-fit package for the USS Gunston Hall and the engineering change proposal (ECP) for the USS Wasp. In 1990 he joined the Human Systems Integration (HSI) Division (SEA 55W5) where he was task leader for auxiliary ships. He is currently the HSI manager for the future technology variant of the SeaLift ship and the future carrier. Association of Scientists and Engineers 33rdAnnual Technical Symposium 26 April 1996. Fred R. Oberman:has B.A. and M.A. degrees from the University of Chicago and Loyola University (experimental psychology) and an M.S. degree in industrial engineering and operations research from Virginia Polytechnic Institute (VPI). He has more than 30 years experience in HSI management planning research analysis design and testing in government and private sector positions. He is currently responsible for NavSea HSI generic research and tool development efforts. He is responsible for Human Engineering Specifications and Standards (Commercial Hypertext) and is the NavSea 03D7 representative on HSI in Performance Specifications and for integration of HSI within Integrated Logistic Support (ILS). He has served as DoD HSI SubTAG chair and member of the Simulation and Modeling Test and Evaluation Display and Control Systems Human Computer Interaction Specifications and Standards and Systems Design Sub Tags as a member of the Society of Naval Architects and Marine Engineers (SNAME) Systems Safety Panel and a member of NATO RSG 14 on man-machine analysis. Thomas B. Malone: CHFEP received a Ph.D. in experimental psychology from Fordham University in 1964. He is president of Carlow

The objectives of Human engineering (HE) are generally viewed as increasing human performance, reducing human error, enhancing personnel and equipment safety, and reducing training and related personnel costs. There are other benefits that are thoroughly consistent with the direction of the Navy of the future, chief among these is reduction of required numbers of personnel to operate and maintain Navy ships. The Naval Research Advisory Committee (NRAC) report on Man-Machine Technology in the Navy estimated that one of the benefits from increased application of man-machine technology to Navy ship design is personnel reduction as well as improving system availability, effectiveness, and safety The objective of this paper is to discuss aspects of the human engineering design of ships and systems that affect manning requirements, and impact human-performance and safety The paper will also discuss how the application of human engineering leads to improved performance, and crew safety, and reduced workload, all of which influence manning levels. Finally, the paper presents a discussion of tools and case studies of good human engineering design practices which reduce manning.

关键词： Human engineering

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CAD CAM GOES TO SEA - THE SAAR-5 DESIGN AND CONSTRUCTION

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NAVAL ENGINEERS JOURNAL 1992年第3期104卷 148-155页

作者： LINDGREN, JR SOLITARIO, WA MOORE, AP STREIFF, MA John R. Lindgren Jr:. is vice president for engineering at Ingalls Shipbuilding Inc. a Division of Litton Industries in Pascagoula Miss. He joined Ingalls in 1958 and has held various positions in the Engineering Division and participated in the design of numerous merchant ships drill rigs submarines and surface combatants and auxiliary support ships. Mr. Lindgren is a 1958 graduate of the University of Southwest Louisiana. His degree is in mechanical engineering and he is also a licensed professional engineer. William A. Solitario:is the director of advanced technology at Ingalls Shipbuilding Inc. in Pascagoula Miss. He received his B.S. degree in chemical engineering from the City University of New York and has 28 years experience in marine engineering and design. His current responsibilities include the direction of Ingalls' IRAD programs and several Navy-funded R&D programs to improve ship's performance and reduce ship's operating costs. He is a member of the Society of Naval Architects and Marine Engineers and past chairman of the Gulf Section East Area. Arnold P. Moore:is the director design engineering at Ingalls Shipbuilding where he is responsible for all new construction design and engineering activities. Prior to promotion to his current position Mr. Moore served as chief naval architect at Ingalls. He has 24 years experience in ship design construction and repair. Mr. Moore holds the professional degree of ocean engineer as well as a master's degree in naval architecture and marine engineering from MIT. He also earned a bachelor's degree in naval science from the U.S. Naval Academy and is a registered professional engineer. Mr. Moore served as an engineering duty officer in the U.S. Navy and is currently a captain in the Naval Reserve. He is a past chairman of the Gulf Section of the Society of Naval Architects and Marine Engineers and a member of the American Society of Naval Engineers and Sigma Xi. Michel A. Streiff:is the manager of CAD/CAM applications at Ingalls Shipbuilding Inc. His

The SA'AR-5 Corvette program is the first major warship construction to be entirely accomplished using a 3-dimensional, interference checked computer based design. This paper discusses the organization and approach used to create the design models which form the basis for interference checking as well as the source of extracted production data. The design or product model is the nucleus of the computer data base that defines the configuration of the entire ship. The data base includes geometry, weight, and material, as well as production control data. The ability of the computer to link such diverse information is the key to maintaining configuration control during the course of the design and construction. The ease with which formatted manufacturing data (both N.C. fabrication and installation) can be extracted enables the preparation of detailed packages containing the desired geometry as well as the associated material and sequencing data, thus assuring the producibility of the design. The SA'AR-5 design is CAD/CAM's state of the art in U.S. shipbuilding.

关键词： Warships

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FIELD SAMPLING OF RESIDUAL AVIATION GASOLINE IN SANDY SOIL

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GROUND WATER MONITORING AND REMEDIATION 1991年第2期11卷 107-120页

作者： OSTENDORF, DW LEACH, LE HINLEIN, ES XIE, YF 1 David W. Ostendorf is an associate professor in the Environmental Engineering Program of the Civil Engineering Department at the University of Massachusetts (Civil Engineering Department University of Massachusetts Amherst MA 01003). His research interests include unconfined aquifer contamination hazardous waste site remediation and analytical modeling of problems in environmental fluid mechanics. Dr. Ostendorf is a registered professional engineer in Massachusetts and a member of the American Geophysical Union American Society of Civil Engineers Soil Science Society of America Water Pollution Control Federation and Association of Environmental Engineering Professors as well as the National Water Well Association.2 Lowell E. Leach is an environmental engineer with the Robert S. Kerr Environmental Research Laboratory of the U.S. Environmental Protection Agency (RS Kerr Environmental Research Laboratory U.S. EPA P.O. Box 1198 Ada OK74820). Leach received his B.S. ingeological engineering at the University of Oklahoma in 1959 and has been a registered professional engineer in Oklahoma since 1966. With 29 years of experience in field applications of geological engineering he is responsible for developing methodology for sampling ground water and subsurface materials for the Robert S. Kerr Environmental Research Laboratory.3 Erich S. Hinlein is a research assistant in the Environmental Engineering Program of the Civil Engineering Department at the University of Massachusetts (Civil Engineering Department University of Massachusetts Amherst MA 01003). His research interests include ground water pollution hazardous waste site investigation and transport processes in unconfined aquifers. Hinlein graduated with a B.S. in electrical and computer engineering from the University of Massachusetts at Amherst in May 1985 and entered the Environmental Engineering Master's Degree Program in January 1989.4 Yuefeng Xie is a postdoctoral research associate in the Environmental Engineering Program of the Civil E

Two complementary field sampling methods for the determination of residual aviation gasoline content in the contaminated capillary fringe of a fine, uniform, sandy soil were investigated. The first method featured field extrusion of core barrels into pint-size Mason jars, while the second consisted of laboratory partitioning of intact stainless steel core sleeves. The barrel extrusion procedure involved jar headspace sampling in a nitrogen-filled glove box, which delineated the 0.7m thick residually contaminated interval for subsequent core sleeve withdrawal from adjacent boreholes. Soil samples removed from the Mason jars (in the field) and sleeve segments (in the laboratory) were subjected to methylene chloride extraction and gas chromatographic analysis to compare their aviation gasoline content. The barrel extrusion sampling method yielded a vertical profile with 0.10m resolution over an essentially continuous 5.0m interval from the ground surface to the water table. The sleeve segment alternative yielded a more resolved 0.03m vertical profile over a shorter 0.8m interval through the capillary fringe. The two methods delivered precise estimates of the vertically integrated mass of aviation gasoline at a given horizontal location, and a consistent view of the vertical profile as well. In the latter regard, a 0.2m thick lens of maximum contamination was found in the center of the capillary fringe, where moisture filled all voids smaller than the mean pore size. The maximum peak was resolved by the core sleeve data, but was partially obscured by the barrel extrusion observations, so that replicate barrels or a half-pint Mason jar size should be considered for data supporting vertical transport analyses in the absence of sleeve partitions.

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