检索结果-内蒙古大学图书馆

Global optimization studies on the 1-d phase problem

INTERNATIONAL JOURNAL OF GENERAL SYSTEMS 1996年第1期25卷 47-59页

作者： Zwick, M Lovell, B Marsh, J Systems Science Ph.D. Program Portland State University Portland Oregon 97207 Systems Science Ph.D. Program Portland State University Portland Oregon 97207 Systems Science Ph.D. Program Portland State University Portland Oregon 97207

The Genetic Algorithm (GA) and Simulated Annealing (SA), two techniques for global optimization, were applied to a reduced (simplified) form of the phase problem (RPP) in computational crystallography. Results were compared with those of ''enhanced pair flipping'' (EPF), a more elaborate problem-specific algorithm incorporating local and global searches. Not surprisingly, EPF did better than the GA or SA approaches, but the existence of GA and SA techniques more advanced than those used in this study suggest that these techniques still hold promise for phase problem applications. The RPP is, furthermore, an excellent test problem for such global optimization methods.

关键词： phase problem computational crystallography global optimization Genetic Algorithm simulated annealing

来源：评论

学校读者我要写书评

暂无评论

Hydroelastic considerations in ship panel design

引用

NAVAL ENGINEERS JOURNAL 1997年第5期109卷 61-66页

作者： McCormick, ME Bhattacharyya, R Mouring, SE Dr. Michael E. McCormick:is a research professor of civil engineering at The Johns Hopkins University. Before joining the Hopkins faculty in 1994 he was a professor of ocean engineering for twenty-five years at the U.S. Naval Academy. In addition he has held full-time faculty positions at Swarthmore College Trinity College (Hartford) and the Catholic University of America. He was also a hydrodynamicist at the David Taylor Model Basin for more than four years. Prof. McCormick received his undergraduate degree in mathematics and physics from AmericanUniversity a masters degree in applied mechanics and a Ph.D. in mechanical engineering from Catholic University a Ph.D. in civil engineering and a Sc.D. in engineering science from Trinity College in Dublin Ireland. He has over 100 publications including two books in the areas of ocean engineering wave mechanics and ocean wave energy conversion. He has also edited two books dealing with ocean engineering. In addition he is co-editor of both the journal Ocean Engineering and the Elsevier book series in ocean engineering. Dr. Rameswar Bhattacharyya:is professor of naval architecture at the U.S. Naval Academy where he has served for twenty-six years and adjunct professor of mechanical engineering at The Johns Hopkins University. Prior to joining the Naval Academy faculty he was a faculty member in the Department of Naval Architecture and Marine Engineering at the University of Michigan. His research experience includes ten years at both the Lubecker Flender-Werke and the Hamburg Ship Model Basin in Germany. His research has led to numerous publications including two books one in the area of ship dynamics and the other in the area of computer-aided ship design. Prof. Bhattacharyya received his undergraduate degree in naval architecture from the Indian Institute of Technology and his doctorate in engineering from the Technical University of Hanover Germany. In addition he holds an honorary doctorate from the University of Veracruz. With Prof. McCormick he co

Panels and all other structural components of surface ships and submarines vibrate when the vessel is underway. The vibratory motions are primarily excited by the power plant. At operational (design) speeds, panels vibrate in their fundamental modes and those associated with their higher harmonic frequencies. The panel motions have rather well-defined energy spectra, which depend on both the structural design, position of the panel and the rotational speed of the single or multiple power plants. The panel motions will interact with the vortices in the adjacent turbulent boundary layer. The interaction can result in either an increase in the frictional drag or a decrease. Because of this, the argument is made that the designs of the panels and their support systems should include considerations of this hydroelastic effect.

关键词： Naval architecture

来源：评论

学校读者我要写书评

暂无评论

developing a prototype concurrent design tool for composite topside structures

引用

NAVAL ENGINEERS JOURNAL 1997年第3期109卷 279-290页

作者： dirlik, S Hambric, S Azarm, S Marquardt, M Hellman, A Bartlett, S Castelli, V Steve Dirlik:began his career at the Naval Surface Warfare Center Carderock Division in 1981 as an aerospace engineer co-op student. He completed his bachelor of science degree in aeropace and ocean engineering from Virginia Polytechnic Institute and State University in 1985 and his master of science degree in aerospace engineering from the University of Maryland in 1990. Mr. Dirlik recently completed a master of science program in applied physics at The Johns Hopins University and currently works in the Radar Cross Section and Target Physics Branch of the Signatures Directorate at the Naval Surface Warfare Center Corderoke Division. He has worked on Navy low observable programs since 1990. Stephen Hambric:is a research associate at the Applied Research Laboratory at The Pennsylvania State University. He received his B. S. and M.S. degree in mechanical engineering from Virginia Polytechnic Institute and State University and his D. Sc. in mechnical engineering from the George Washington University. He has worked on several computer aided multidiscikplinary design and optimization projects over the years including an automated propeller design system and a structural acoustic optimization capability. Dr. Shpour Azarm:is currently working as an associate professor with the Design and Manufacturing Group of the Department of Mechanical Engineering at the University of maryland at College Park. Dr Azarm's expertise is in the areas of optimization-based designed and concurrent design and optimization of multidisciplinary systems. He was a consultant at Black & Decker Corporation (summer 1996) and worked as a Navy senior summer faculty fellow (summer 1995) and a NASA summer faculty fellow (summer 1994). He was a visiting scientist at NASA Langley Research Center for Multidisciplinary Analysis and Applied Structural Optimzatiom at the University of Siegen in Germany (spring 1992) and the Design Institute of the Technical University of Denmark (summer 1990). Dr Azarm was an associate technical editor of the ASME Jour

A prototype concurrent engineering tool has been developed for the preliminary design of composite topside structures for modern navy warships. This tool, named GELS for the Concurrent Engineering of Layered Structures, provides designers with an immediate assessment of the impacts of their decisions on several disciplines which are important to the performance of a modern naval topside structure, including electromagnetic interference effects (EMI), radar cross section (RCS), structural integrity, cost, and weight. Preliminary analysis modules in each of these disciplines are integrated to operate from a common set of design variables and a common materials database. Performance in each discipline and an overall fitness function for the concept are then evaluated. A graphical user interface (GUI) is used to define requirements and to display the results from the technical analysis modules. Optimization techniques, including feasible sequential quadratic programming (FSQP) and exhaustive search are used to modify the design variables to satisfy all requirements simultaneously. The development of this tool, the technical modules, and their integration are discussed noting the decisions and compromises required to develop and integrate the modules into a prototype conceptual design tool.

关键词： Warships

来源：评论

学校读者我要写书评

暂无评论

Operational systems, logistics engineering and technology insertion

引用

NAVAL ENGINEERS JOURNAL 1997年第3期109卷 205-220页

作者： Grubb, MJ Skolnick, A Michael J. Grubb:has perfomzed naval engineering at the Crane Division Naval Surface Warfare Center (NSWC) for more than twenty-five years. He currently the program manager for the Sustainable Hardware and Affordable Readiness Practice Program (SHARP). is a Navy-wide logistics research and development prgram aimed at the successful transiton of proved technologies inot the fleet. SHARP focuses on reducing acquisition performance capability reliability maintainability and readiness of these systems. Mr. Grubb has served as a department director for the past eleven years. His most recent assignment was as director of the Tactical Computer Resources and Test Equipment Department. This organization provided acquisition and in-service engineering support of the Navy's tectical embedded computers priphirals displays and mass memory storage devices. The organization also provided a complete range of product engineering and metrology engineerig services for SSP NevSeaSysCom and the Trident Program. Prior to this appointment Mr. Grubb was deptuy director psysical security programs department and site responsible for program management and system integration of ashore integrated security systems. Mr. Grubb holds a B.S. degree in industrial engineering from Iowa State Universtiy an M.S. degree in industrial engineering from Purdue University and has copleted the course work (Dec.'96 for a master's degree in public and environment affairs at Indiana University-Purdue Univeristy Indianapolis. Dr. Alfred Skolnick operates System Science Consultants (SSC) specilizing in strategic planning technical program definiton technology assessment and engineering analyses on selected matters of national interest. He has taught physics mathematics and management sciences at University of Virginia and Marymount University and is currently adjunct professor of mathematics at Northern Virginia Community College. Form 1985 to 1989 he was president of the American Society of Noval Engineers. Dr. Skolnick served at Applied Physic

In an era of fiscal austerity, downsizing and unforgiving pressure upon human and economic capital, it is an Augean task to identify resources for fresh and creative work. The realities of the day and the practical demands of more immediate fleet needs can often dictate higher priorities. Yet, the Navy must avoid eating its seed corn. Exercising both technical insight and management foresight, the fleet, the R&d community, the Office of the Chief of Naval Operations (OpNav) and the product engineering expertise of the Naval Surface Warfare Center (NSWC) are joined and underway with integrated efforts to marry new, fully demonstrated technologies and operational urgencies. defense funding today cannot sponsor all work that can be mission-justified over the long term because budgets are insufficient to support product maturation within the classical development cycle. However, by rigorous technical filtering and astute engineering of both marketplace capabilities and currently available components, it is possible in a few select cases to compress and, in effect, integrate advanced development (6.3), engineering development (6.4), weapon procurement (WPN), ship construction (SCN), operation and maintenance (O&M,N) budgetary categories when fleet criticalities and technology opportunities can happily meet. In short, 6.3 funds can be applied directly to ''ripe gateways'' so modern technology is inserted into existing troubled or aging systems, sidestepping the lengthy, traditional development cycle and accelerating practical payoffs to recurrent fleet problems. To produce such constructive results has required a remarkable convergence of sponsor prescience and engineering workforce excellence. The paper describes, extensively, the philosophy of approach, transition strategy, polling of fleet needs, technology assessment, and management team requirements. The process for culling and selecting specific candidate tasks for SHARP sponsorship (matching operational need with t

关键词： Naval vessels

来源：评论

学校读者我要写书评

暂无评论

Chaos and detection

引用

physical Review E 1996年第5期53卷 4514-4514页

作者： Andrew M. Fraser Systems Science Ph.D. Program Portland State University Portland Oregon 97207-0751

I report on numerical experiments in which a detector reliably found chaotic signals at signal to noise ratios as low as - 15 dB. The detector was based on a variant of the hidden Markov models used in speech research. The task was particularly difficult because the Fourier power spectrum of the noise was constructed to match the spectrum of the signal. I review likelihood ratio detectors, limitations on the performance of linear models implied by the broad Fourier power spectra of chaotic signals, and the upper limit that the Kolmogorov-Sinai (KS) entropy of a chaotic system places on the expected log likelihood attainable by any model. I find that KS entropy estimates indicate that even better detection performance is possible.

关键词：

来源：评论

学校读者我要写书评

暂无评论

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

引用

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

来源：评论

学校读者我要写书评

暂无评论

Application of high temperature superconducting wire to magnetostrictive transducers for underwater sonar

引用

NAVAL ENGINEERS JOURNAL 1997年第1期109卷 31-39页

作者： Joshi, CH Lindberg, JF Clark, AE Dr. Chad H. Joshi:is president of Energen Incorporated an engineering and development firm specializing in cryogenic and electromechanical systems. The research presented here was conducted while he was employed at American Superconductor Coporation where he held both technical and program management positions. While there Dr. Joshi managed the development of several demonstration products including the sonar transducer presented here. He holds M.S. and Sc.D. degreesfrom the Massachusetts Institute of Technology and a B.S. degree from the Worcester Polytechnic Institute. He has worked in several diverse fields including solar energy fluidized bed technology and superconductivity. His work on stochastic analysis of solar insolation was recognized by the ASME and his doctoral research was accorded international recognition for its unique contribution to understanding quenching in superconducting magnets. Dr. Joshi has numerous patents and more than thirty-five technical publications to his credit. He is a registered Professional Engineer in Massachusetts and an active member of ASME and IEEE. He is a co-founder and treasurer of the New England Chapter of the Cryogenics Society of America. He will be listed in Whos Who in the East in 1997. Jan Lindberg:is a physicist in the Transducers and Arrays Division of the Naval Undersea Warfare Center in New London Connecticut. He leads NUWC'S exploratory development efforts for transduction science and currently is spearheading an effort to introduce high-energy density active materials into tactical sonar systems. With the discovery of high temperature superconductivity he saw the potential benefit of integrating several emerging technologies and enticed American Superconductor Corp. to develop a high temperature superconducting transducer which resulted in the March 1993 demonstration of the world's first integrated high temperature superconducting device. Mr. Lindberg's current interests involve design of high power ultrasonic copolymer arrays characterization of

A low-frequency underwater acoustic transducer integrating high-temperature superconducting (HTS) coils and terbium-dysprosium (Tbdy) magnetostrictive material was designed, fabricated and tested. This represents a novel application for high-temperature superconductivity and is a first example of an integrated system involving HTS coils cooled by a mechanical cryocooler. It also brings HTS technology together with a novel magnetic materials technology. The I-ITS coils were fabricated using react-and-wind BiSrCaCuO-2223 HTS wires. They produce a peak field of 0.1 Tesla at 50 K. A single-stage, Stirling-cycle cryocooler was used to cool the coils and the Tbdy driver to cryogenic temperatures (50-65K). The coils provide an AC magnetic field superimposed on a dC bias field, which produces oscillatory strain within the magnetostrictive rod;this motion is transmitted through a cryostat to two head masses which project sound into the surrounding environment. High power acoustic output can be obtained by operating the transducer at its resonance frequencies of 520 Hz in air and 430 Hz underwater. This development demonstrates that, unlike low temperature superconductors, HTS wires can be considered for AC applications due to the low losses in these superconductors and the higher heat capacities of materials at temperatures above liquid helium.

关键词： Underwater equipment

来源：评论

学校读者我要写书评

暂无评论

Remote access to neurosurgical ICU physiological data using the world wide web

引用

Studies in Health Technology and Informatics 1996年 29卷 242-249页

作者： Nenov, Valeriy Klopp, John Division of Neurosurgery University of California at Los Angeles School of Medicine Los Angeles CA 90024 United States Computer Science Department United States Interdepartmental Neuroscience Ph.D. Program University of California at Los Angeles Los Angeles CA 90024 United States

There is a significant demand by physicians and clinical researchers for remote access to continuously acquired physiological patient data. Until recently such access was technically unfeasible. However, with the recent development of Internet-based World Wide Web (WWW) client/server applications and underlying communication protocols, there is now a real possibility for the development of costeffective, platform independent solutions to this problem. We have devised a way using existing WWW tools and minimal startup costs to provide access to current as well as previously acquired physiological patient data. physicians and clinical researchers can obtain access to these data through personal computers located in the office, at home or even through portable computers while traveling to conferences or while on vacation. © The authors 1996.

关键词： Hospital data processing

来源：评论

学校读者我要写书评

暂无评论

Ionic current model of the retinal photoreceptor and simulation analysis of the photoresponses

引用

SYSTEMS ANd computerS IN JAPAN 1996年第12期27卷 10-21页

作者： Usui, TOS Kamiyama, Y Faculty of Information Engineering Toyohashi University of Technology Shim Usui:graduated in 1974 with his Ph.D. degree in Computer Science from the University of California. He was appointed Research Associate at Nagoya University in 1974 a Lecturer at Toyohashi University of Technology in 1979 and an Associate Professor and then a Professor in 1986. He has been engaged in research on physiological information engineering and physiological engineering. He is the author of Basic Physwlqicul Signal Processing. He is a member of IEE Institute of Measurement and Automation Japan Institute of Information Processing Japan Institute of Medical Engineering Japan Institute of Physiology Japan Institute of Neural Science Japan Institute of Neural Networks Japan: and INNS. He is an IEEE fellow.

The fact that the reception of optical information by the retinal photoreceptor and the process of its transformation to the membrane voltage response are due to an interaction between the photocurrent from the outer segment and each ionic current in the inner segment has been confirmed by many physiological experiments. However, the properties of each ionic current in the photoreceptor have not been clear since no physiologically reliable model of the retinal photoreceptor has been constructed. This paper proposes a model of a retinal photoreceptor, which is a combination of the outer segment model (devised by Torre et al.) and the inner segment model (devised by the present authors). It has been confirmed that this model can accurately represent the electron physiological properties of a retinal photoreceptor. Using this model simulation, the relationship between the photocurrent and the photoresponse dynamics, and an oscillatory phenomena caused by a strong light flash have been analyzed. The results show that the dynamic and nonlinear response characteristics of a retinal photoreceptor are due to the interactions between the nonlinear ionic current in the inner segment and the mechanism of the intracellular calcium.

关键词： retinal photoreceptor photoresponse intracellular calcium mechanism simulation analysis

来源：评论

学校读者我要写书评

暂无评论

The rational behavior software architecture for intelligent ships

引用

NAVAL ENGINEERS JOURNAL 1996年第2期108卷 43-55页

作者： Byrnes, RB Healey, AJ McGhee, RB Nelson, ML Kwak, SH Brutzman, dP [?]Ronald B. Byrnes is a U.S. Army Lieutenant Colonel commissioned into the Signal Corps in 1979. He has served in a variety of positions associated with tactical and operational communications at company brigade and corps level. L. C. Byrnes became a member of the Army Acquisition Corps in 1993 and is currently a computer scientist with the Software Technology Branch of the Army Research Lab. His current work includes continuation of his doctoral research into high-level control of autonomous vehicles contributions to the Army's electronic records management and data standardization efforts and automated support for flight plan verification. L.C. Byrnes received a B.S. degree in Mathematics from Midwestern State University in 1979 an M.S.E.E. degree from the Naval Postgraduate School in 1989 and a Ph.D. in Computer Science from the Naval Postgraduate School in 1993.

The solutions to the power projection, transportation, and operational needs of the Navy as it faces the 21st century must account for reduced manning levels. This leads naturally to increased use of computers, automation, and intelligent systems in the concept and design of the next generation of ships. In addition to the acknowledged hardware needs, the problem of autonomic and autonomous control of shipboard systems and missions are amenable to and will, in fact, require software solutions. despite current technology, large, reliable software systems are difficult to achieve because correctness in requirements analysis, design, implementation, testing, modification, and maintenance of software are difficult. Software is also difficult to quantize and display;hence, the effort and costs involved in its development are easily underestimated. This paper describes an approach to the problem of providing structure, in the form of a software architecture, to the software performing autonomous control of missions and their related tasks. In concert with the need to reduce complexity, the architecture must support simple, rapid reconfiguration of code should vehicle capabilities or mission requirements change. Building upon recent efforts with control of Autonomous Underwater Vehicles (AUVs), we propose a tri-level control system architecture called the Rational Behavior Model (RBM) as an approach to autonomous and autonomic control of surface ship missions and systems.

关键词： Electronic ship equipment

来源：评论

学校读者我要写书评

暂无评论

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案：

请选择收藏分类：

通借通还

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：