检索结果-内蒙古大学图书馆

1992 IEEE Workshop on Neural Networks for Signal Processing II

作者： Fernamtes, R.A. Jernigan, M.E. Earth Observation Laboratory Institute for Space and Terrestrial Science Canada Department of Systems Design Engineering University of Waterloo WaterlooONN2L 3G1 Canada

ISBN: (纸本)0780305574

A multi-level image segmentation network is described. Each level uses anisotropic diffusion to segment a multispectral image at successively lower resolutions. Texture and statistical similarities between and within levels guides the diffusion process. The network outperforms a fuzzy clustering scheme in the segmentation of a high-resolution multispectral airiel image.

关键词： Image segmentation

来源：评论

学校读者我要写书评

暂无评论

IMAGE COMPRESSION BY VARIABLE BLOCK TRUNCATION CODING WITH OPTIMAL THRESHOLD

引用

IEEE TRANSACTIONS ON SIGNAL PROCESSING 1991年第1期39卷 208-212页

作者： KAMEL, M SUN, CT GUAN, L Pattern Analysis and Machine Intelligence Laboratory Department of Systems Design Engineering University of Waterloo Waterloo ONT Canada

In this correspondence we propose two modifications to the block truncation coding techniques. The first modification allows the partitioning of the image into variable size blocks rather than fixed size. The second m... 详细信息

关键词： Image coding Mean square error methods Pixel Image reconstruction Sun Vector quantization Tail Pattern analysis Machine intelligence System analysis and design

来源：评论

学校读者我要写书评

暂无评论

ANALYSIS OF 3-D MICROWAVE RESONATORS USING COVARIANT-PROJECTION ELEMENTS

引用

IEEE TRANSACTIONS ON MICROWAVE THEORY AND TECHNIQUES 1991年第11期39卷 1895-1899页

作者： WEBB, JP MINIOWITZ, R Computational Analysis and Design Laboratory Department of Electrical Engineering McGill University Montreal QUE Canada Electromagnetics Department RAFAEL Advanced Defense Systems Limited Haifa Israel

Three-dimensional microwave resonators of arbitrary shape can be analyzed with the finite element method using covariant-projection elements, curvilinear bricks which impose only tangential field continuity. The method produces no spurious modes, and works well even when sharp metal edges are present. The matrices involved, though large, are sparse;an appropriate sparse eigenvalue algorithm allows the method to run in modest amounts of memory. Results are presented for a number of test cases, including a rectangular microstrip resonator.

关键词： Finite element methods Magnetic resonance Shape Eigenvalues and eigenfunctions Microwave devices Magnetic fields Magnetic analysis Microwave theory and techniques Covariance matrix Sparse matrices

来源：评论

学校读者我要写书评

暂无评论

A sensor model registration technique for mobile robot localization

A sensor model registration technique for mobile robot local...

引用

IEEE International Symposium on Intelligent Control (ISIC)

作者： S.Y.T. Lang A.K.C. Wong Autonomous Systems Laboratory Institute of In formation Technology National Research Council Canada Ottawa ONT Canada Pattern Analysis and Machine Intelligence Laboratory Department of Systems Design Engineering University of Waterloo Waterloo ONT Canada

A method for mobile robot localization using natural environmental features is presented. An attributed graph boundary representation of free space is used. A local sensor model is registered with a global model by a subgraph isomorphism technique. Geometric and structural knowledge is used to search for mappings. The set of possible mappings is incrementally determined. Simultaneously, the associated coordinate transformation between the global and local models is refined. The model registration technique is implemented in software, and two examples are shown.< >

关键词： Mobile robots Sensor phenomena and characterization Dead reckoning Sonar navigation Councils Wires Laboratories Information technology Space technology Calibration

来源：评论

学校读者我要写书评

暂无评论

SMALL SHIPS, advanced TECHNOLOGY AND WARFIGHTING PERFORMANCE

引用

NAVAL ENGINEERS JOURNAL 1991年第3期103卷 30-45页

作者： SKOLNICK, DH SKOLNICK, A David H. Skolnickhas practiced naval engineering in both government and industry. He has supported the Military Sealift Command and the Naval Sea Systems Command Ship Design Group and Amphibious Ship Acquisition Program Office participating in the design and assessment of ship structure evaluation of intact and damaged stability and arrangements during design and construction phases of acquisition conversion and overhaul. He is currently involved in systems engineering and integration. Recent responsibilities have included requirements analyses and feasibility studies interface analyses and computer aided analyses. He received his B.S. in naval architecture and marine engineering from Webb Institute of Naval Architecture in 1982 (as an ASNE scholar) and is currently an M.S. candidate in systems engineering at the University of Virginia. Alfred Skolnickserved over 30 years as an engineering duty officer and retired from the Navy with the rank of captain in 1983. His early assignments included tactical missile engineering shipboard duty and Polaris submarine inertial navigation. He later served in the Deep Submergence Systems Project was project director surface effect ships (SES) David Taylor Model Basin director of technology Joint Navy-Commerce SES Program director combat systems Naval Sea Systems Command and project manager directed energy weapons. His awards include the Navy League's Parsons Award in 1979 for scientific and technical progress ASNE's Gold Medal in 1981 for high energy laser development the Navy Legion of Merit in 1983 National Capital Engineer of the Year in 1986 and the American Defense Preparedness Association Gold Medal in 1988 for contributions to strategic defense. He was president of ASNE from 1985–1989. He received his B.S. in mathematics from Queens College his M.A. in mathematics from Columbia University his M.S. in electrical engineering from U.S. Naval Postgraduate School and his Ph.D. in electrical engineering/applied mathematics from Polytechnic University. He w

Changing threat requirements and radical budget shifts imply that Navy operational needs will broaden and engineering solutions will face tougher constraints. Existing and emerging technology promise increased combat capability in smaller packages;space-based assets will allow operator orchestration of widely dispersed naval units via connectivity attributes previously unavailable. Tactical data relay by downlink may permit reallocation of responsibilities among several platforms, space, air, or seaborne, so ships can be outfitted for custom-use (sensing, unique data processing, high-firepower) and optimized to meet specific mission needs. These evolving capabilities demand a fresh look at ship concepts and prospective force structures consistent with global and fiscal realities. Warfighting performance formerly unknown in small ship design may offer a very effective solution to the intricate, interacting issues of falling defense budgets, diverse operational requirements and complex national priorities. Multimission ships which take advantage of new or current technology to reduce ship size, manning and cost could be affordable in sufficient numbers to meet our continuing worldwide obligations, complement our larger ships' force structure, and produce a balanced fleet. These same ships could satisfy U.S. maritime needs beyond the Navy and improve export trade through foreign military sales (FMS).

关键词： Naval Warfare

来源：评论

学校读者我要写书评

暂无评论

COMPUTER-AIDED MANUFACTURING OF advanced MICROWAVE MODULES

引用

INTERNATIONAL JOURNAL OF MICROWAVE AND MILLIMETER-WAVE COMPUTER-AIDED engineering 1991年第1期1卷 90-111页

作者： PAVIO, AM PAVIO, JS CHAPMAN, JE BOGGAN, GH Texas Instruments Incorporated P.O. Box 655474 Dallas. Texas 75265 Jeanne Pavio is the Manager of the Microwave Advanced Packaging Group at Texas Instruments where she has been cmployed since 1980. She received the BA degree in 1971 and the MS in 1972 both from the University of Connecticut. Her experience base has included the fabrication and assembly of thick and thin film hybrids. At the Texas Instruments Hybrid Microelectronics Laboratory Jeanne implemented nitrogenfireable thick film for ceramic application in surface-mount technology and hybrids. For the last six years she has focused on the automated assembly and packaging of GaAs Monolithic Microwave Integrated Circuits and devices. This has encompassed development of fluxless furnace reflow and void-free vacuum reflow of GaAs components as well as development of automated wirebonding to GaAs Microwave Hybrids. She was instrumental in directly applying this technology to active phased array module production. Her efforts presently involve the implementation of high-volume techniques and automation for insertion of MMIC technology in a cost-effective highvolume environment. She has authored numerous papers involving hybrid fabrication and assembly technology and in particular involving automated assembly and packaging of GaAs MMIC devices. James E. Chapman Jr. was born in Dallas Texas in 1943. He received the BS and MS degrees in Electrical Engineering from Southern Methodist University (SMU) in 1966 and 1968 respectively. During this time he was associated with the Semiconductor Group of Texas Instruments Incorporated as an undergraduate engineering cooperative student working with various silicon products and processes. Mr. Chapman is currently a Senior Member of the Technical Staff assigned to the Microwave Technology and Products Division of the Defense Systems and Electronics Group. In this position he is currently technical director of the Technology Development for Solid-state Phased-Arrays (TDSSPA) Program. This program is a task-ordere

The application of computer-aided manufacturing (CAM) techniques to the assembly and test of a low-cost, high-volume X-band Radar T/R module will be investigated by highlighting the differences between low frequency and microwave CAM methods, focusing on the difficulties of automated testing, evaluation, and circuit tuning. The problems encountered when implementing high-precision automated assembly and test methods, which include wire-bonding, soldering, piece-part placement, thin wafer GaAs probing, and a novel implementation of a microwave circuit laser-tuning technique will also be discussed. These CAM techniques, combined with integrated MMIC technology, are then used to illustrate a manufacturing philosophy targeted toward high-volume microwave module production.

关键词： Microwave devices

来源：评论

学校读者我要写书评

暂无评论

HYDRODYNAMIC EFFICIENCY IMPROVEMENTS FOR UNITED-STATES NAVY SHIPS

引用

NAVAL ENGINEERS JOURNAL 1991年第3期103卷 74-90页

作者： MCCALLUM, D ENGLE, AH PLATZER, GP KARAFIATH, G Donald McCallumis a supervisory naval architect in the Auxiliary Amphibious and Mine Warfare Ship Hydrodynamics Branch of the Naval Sea Systems Command. He has worked in ship design in his native Scotland before coming to the United States via Canada. Mr. McCallum has a M.Sc. degree from the University of Michigan and a B.Sc. from Strathclyde University (Glasgow). He is a member of SNAME ASNE and ASE. Allen H. Engleis a naval architect with the Hull Form and Hydrodynamic Performance Division of the Naval Sea Systems Command (NavSea). He received his B.S. degree in engineering science from the State University of New York at Buffalo in 1977 and his M.S. degree in ocean engineering from the University of Hawaii in 1979. Since 1980 he has worked for NavSea where he has been assigned to the Philadelphia Naval Shipyard SupShip Seattle and the U.S. Naval Academy Hydromechanics Laboratory. Selected as NavSea's Engineer of the Year for 1989 Mr. Engle is currently the program director for the Navy's Hydrodynamic Loads Technology Development Program. Prior to his current assignment Mr. Engle was technical director of the Navy's Ship Efficiency Improvement Program and task leader for hydrodynamic design for the LHD-5 AO-177 (Jumbo) AE-36 LSD-41 and FFX ship designs. Mr. Engle is a member of both ASNE and SNAME. Gregory Platzeris currently employed with Arneson Marine Inc. As manager of applications engineering Mr. Platzer is responsible for the development of propulsion specifications for articulated surface drive units matched to high-speed partially submerged propellers. Prior to November 1990 Mr. Platzer was the head of the Surface Ship Propeller Branch at the Naval Sea Systems Command. He had worked for the Navy in the field of propulsor analysis since 1977 initially at the David Taylor Research Center. Mr. Platzer graduated in 1977 from the University of Michigan with a B.S. degree in naval architecture. Gabor Karafiathis a member of the Ship Hydromechanics Department at the David Taylor Research Center.

This paper reports on an investigation of the applicability of recent hull efficiency improvement concepts to U.S. Navy ships. Among the concepts investigated were stern flaps, Grim Wheels, alternate aftbody configurations, bulbous bows, and flow modifying ducts. Extensive model testing was conducted at the David Taylor Research Center (DTRC) for each concept, and care was taken to check out critical propeller cavitation and noise aspects associated with the investigation of alternate stern configurations and Grim Wheel concepts. A guiding principle in this program was to utilize the expertise available both here and abroad so that each design concept would have the greatest chance of success. As a result of these investigations, significant gains in fuel economy were obtained. Specifically, full scale trials of FFG-25 (USS Copeland), equipped with and without a stern flap, demonstrated that fuel savings of 5-9% are achieved at speeds above 12 knots. In addition, fuel savings of 9.4% for T-AGS 39 equipped with a Grim Wheel and 5.6% for the combination of a large bulbous bow and a large diameter/low RPM propeller on AE-36 have been predicted. The paper concludes with a direction for future applications to U.S. Navy, and other ships.

关键词： Warships

来源：评论

学校读者我要写书评

暂无评论

ROLE OF SIMULATION IN RAPID PROTOTYPING FOR CONCEPT DEVELOPMENT

引用

NAVAL ENGINEERS JOURNAL 1991年第3期103卷 204-211页

作者： KING, JF BARTON, DE J. Fred King:is the manager of the Advanced Technology Department for Unisys in Reston Virginia. He earned his Ph.D. in mathematics from the University of Houston in 1977. He has been principal investigator of research projects in knowledge engineering pattern recognition and heuristic problem-solving. Efforts include the development of a multi-temporal multispectral classifier for identifying graincrops using LANDSAT satellite imagery data for NASA. Also as a member of the research team for a NCI study with Baylor College of Medicine and NASA he helped develop techniques for detection of carcinoma using multispectral microphotometer scans of lung tissue. He established and became technical director of the AI Laboratory for Ford Aerospace where he developed expert scheduling modeling and knowledge acquisition systems for NASA. Since joining Unisys in 1985 he has led the development of object-oriented programming environments blackboard architectures data fusion techniques using neural networks and intelligent data base systems. Douglas E. Barton:is manager of Logistics Information Systems for Unisys in Reston Virginia. He earned his B.A. degree in computer science from the College of William and Mary in 1978 and did postgraduate work in London as a Drapers Company scholar. Since joining Unisys in 1981 his work has concentrated on program management and software engineering of large scale data base management systems and design and implementation of knowledge-based systems in planning and logistics. As chairman of the Logistics Data Subcommittee of the National Security Industrial Association (NSIA) he led an industry initiative which examined concepts in knowledge-based systems in military logistics. His responsibilities also include evaluation development and tailoring of software engineering standards and procedures for data base and knowledge-based systems. He is currently program manager of the Navigation Information Management System which provides support to the Fleet Ballistic Missile Progr

A valuable technique during concept development is rapid prototyping of software for key design components. This approach is particularly useful when the optimum design approach is not readily apparent or several known alternatives need to be rapidly evaluated. A problem inherent in rapid prototyping is the lack of a "target system" with which to interface. Some alternatives are to develop test driver libraries, integrate the prototype with an existing working simulator, or build one for the specific problem. This paper presents a unique approach to concept development using rapid prototyping for concept development and scenario-based simulation for concept verification. The rapid prototyping environment, derived from artificial intelligence technology, is based on a blackboard architecture. The rapid prototype simulation capability is provided through an object-oriented modeling environment. It is shown how both simulation and blackboard technologies are used collectively to rapidly gain insight into a tenacious problem. A specific example will be discussed where this approach was used to evolve the logic of a mission controller for an autonomous underwater vehicle.

关键词： Military engineering

来源：评论

学校读者我要写书评

暂无评论

MAGNETOHYDRODYNAMIC SUBMARINE PROPULSION systems

引用

NAVAL ENGINEERS JOURNAL 1991年第3期103卷 141-157页

作者： SWALLOM, DW SADOVNIK, I GIBBS, JS GUROL, H NGUYEN, LV VANDENBERGH, HH Daniel W. Swallomis the director of military power systems at Avco Research Laboratory Inc. a subsidiary of Textron Inc. in Everett Mass. Dr. Swallom received his B.S. M.S. and Ph.D. degrees in mechanical engineering from the University of Iowa Iowa City Iowa in 1969 1970 and 1972 respectively. He has authored numerous papers in the areas of power propulsion and plasma physics and currently is a member of the Aerospace Power Systems Technical Committee of the AIAA. Dr. Swallom has directed various programs for the development of advanced power generation systems lightweight power conditioning systems and advanced propulsion systems for marine applications. His previous experience includes work with Odin International Corporation Maxwell Laboratories Inc. Argonne National Laboratory and the Air Force Aero Propulsion Laboratory. Currently Dr. Swallom is directing the technical efforts to apply magnetohydrodynamic principles to a variety of propulsion and power applications for various marine vehicles and power system requirements respectively. Isaac Sadovnikis a principal research engineer in the Energy Technology Office at Avco Research Laboratory Inc. a subsidiary of Textron Inc. He received his B.S. in engineering (1974) B.S. in physics (1975) M.S. in aeronautics and astronautics (1976) and Ph.D. in physics of fluids (1981) at the Massachusetts Institute of Technology. Dr. Sadovnik has been involved in research work funded by DARPA concerning the use of magnetohydrodynamics for underwater propulsion. He has built theoretical models that predict the hydrodynamic behavior of seawater flow through magnetohydrodynamic ducts and their interaction with the rest of the vehicle (thrust and drag produced). In addition Dr. Sadovnik has been involved in research investigations geared toward the NASP program concerning the use of magnetohydrodynamic combustion-driven accelerator channels. Prior to joining Avco Dr. Sadovnik was a research assistant at MIT where he conducted experimental and

Magnetohydrodynamic propulsion systems for submarines offer several significant advantages over conventional propeller propulsion systems. These advantages include the potential for greater stealth characteristics, increased maneuverability, enhanced survivability, elimination of cavitation limits, greater payload capability, and the addition of a significant emergency propulsion system. These advantages can be obtained with a magnetohydrodynamic propulsion system that is neutrally bouyant and can operate with the existing submarine propulsion system power plant. A thorough investigation of magnetohydrodynamic propulsion systems for submarine applications has been completed. During the investigation, a number of geometric configurations were examined. Each of these configurations and mounting concepts was optimized for maximum performance for a generic attack class submarine. The optimization considered each thruster individually by determining the optimum operating characteristics for each one and accepting only those thrusters that result in a neutrally buoyant propulsion system. The results of this detailed optimization study show that the segmented, annular thruster is the concept with the highest performance levels and greatest efficiency and offers the greatest potential for a practical magnetohydrodynamic propulsion system for attack class submarines. The optimization study results were used to develop a specific point design for a segmented, annular magnetohydrodynamic thruster for an attack class submarine. The design point case has shown that this thruster may be able to provide the necessary thrust to propel an attack class submarine at the required velocity with the potential for a substantial acoustic signature reduction within the constraints of the existing submarine power plant and the maintenance of neutral buoyancy. This innovative magnetohydrodynamic propulsion system offers an approach for submarine propulsion that can be an important contributio

关键词： Ship Propulsion

来源：评论

学校读者我要写书评

暂无评论

Automating the knowledge acquisition process in the construction of medical expert systems

引用

Artificial Intelligence In Medicine 1990年第5期2卷 267-292页

作者： Wong, Andrew K.C. Chan, Keith C.C. PAMI Laboratory Department of Systems Design Engineering University of Waterloo Waterloo Ont. N2L 3G1 Canada

In this paper, an inductive knowledge acquisition method that can be used as an aid for building certain medical expert systems is described. Given a collection of subjects that are described in terms of one or more attributes and are preclassified into a number of known classes (such as disease classes or classes that require certain type of therapy), this method is capable of detecting inherent probabilistic patterns in the data. Classificatory knowledge is then synthesized based on the detected patterns and made explicit in the form of classification rules. Based on these rules, the class membership of a subject can then be determined. The method has been implemented and tested with both simulated and real-world data. It has also been compared to some existing learning systems. The results show that the proposed learning method performs better both in terms of computational efficiency and classification accuracy. © 1990.

关键词： Classification Mutural information Noisy training data Partial matching Probabilistic patterns Probabilistic rules Weight of evidence

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：