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Proximal femoral density patterns are consistent with bicentric joint loads

computer Methods in Biomechanics and Biomedical Engineering 1999年第4期2卷 271-283页

作者： Fischer, Kenneth J. Jacobs, Christopher R. Levenston, Marc E. Cody, Dianna D. Carters, Dennis R. Musculoskeletal Research Center Department of Orthopaedic Surgery University of Pittsburgh Pittsburgh PA 15213 United States Department of Orthopaedics Musculoskeletal Research Laboratory Pennsylvania State University School of Medicine Hershey PA 17033 United States Department of Electrical Engineering and Computer Science Continuum Elect romechanics Mhoratory Massachusetts Institute of Technology Hershey MA 02139 United States Department of Diagnostic Radiology Division of Radiologic Physics and Engineering Henry Ford Hospital Detroit MI 48202 United States Department of Veterans Affairs Medical Center Rehabilitation Research and Development Center Palo Alto CA 94304-1200 United States Department of Mechanical Engineering Stanford University Biomechanical Engineering Program Stanford CA 94305-402 United States

We developed an alternate method for density-based load estimation and applied it to estimate hip joint load distributions for two femora. Two-dimensional finite element models were constructed from single energy quantitative computed tomography (QCT) data. Load estimation was performed using five loading regions on the femoral head. Within each loading region, individual nodal loads, normal to the local surface, were supplied as input to the load estimation. An optimization procedure independently adjusted individual nodal load magnitudes in each region, and the magnitudes of muscle forces on the greater trochanter, such that the applied tissue stimulus approached the reference stimulus throughout the model. Dominant estimated load resultant directions were generally consistent with published experimental data for loads during gait. The estimated loads also suggested that loads near the extremes of the articulating surface may be important (even required) for development and maintenance of normal bone architecture. Estimated load distributions within nearly all regions predicted bicentric loading patterns, which are consistent with observations of hip joint incongruity. Remodeling simulations with the estimated loads predicted density distributions with features qualitatively similar to the QCT data sets. This study illustrates how applications of density-based bone load estimation can improve understanding of dominant loading patterns in other bones and joints. The prediction of bicentric loading suggests a very fine level of local adaptation to details of joint loading. © 1999 OPA (Overseas Publishers Association) N.V.

关键词： Finite element method

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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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A comparison of ada and pascal in an introductory computer science course 98

A comparison of ada and pascal in an introductory computer s...

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1998 Annual ACM SIGAda International Conference on Ada, SIGAda 1998

作者： Murtagh, Jeanne L. Hamilton, John A. Software Professional Development Program Air Force Institute of Technology Wright-Patterson AFBOH45433-7765 United States US Army D/Electrical Engineering and Computer Science United States Military Academy West PointNY10996-1787 United States

ISBN: (纸本)1581130333

Pascal's long and successful run at West Point illustrated Winston Churchill's dictum that, "The absence of alternatives clears the mind wonderfully." However, by the mid-90s, the United States Military Academy was finding that Pascal, long the educational workhorse, was no longer the clear choice for serious computer science education. The decision was taken to evaluate alternatives to Pascal. The criteria selected for programming language evaluation were student learning outcomes based on course goals and objectives. The controlled educational environment of a service academy provides an excellent opportunity to conduct research using control groups and experimental groups. We conducted a side by side comparison of the use of Pascal, which was specifically designed for instructional purposes, and Ada in an introductory course. The experiment demonstrated that students were much more successful in Ada than in Pascal, and led to the revision of the Academy core curriculum to use Ada 95 in our introductory computer science class. This paper discusses the details of our comparison, citing specific examples to illustrate a rational basis for evaluating programming language features against course objectives.

关键词： Students

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Toward biomimetic oculomotor control

Toward biomimetic oculomotor control

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IEEE International Workshop on Intelligent Robots and Systems (IROS)

作者： T. Shibata S. Schaal Kawato Dynamic Brain Project ERATO Japan Science and Technology Corporation (JST) Kyoto Japan Department of Computer Science and Neuroscience Program University of Southern California USA

Oculomotor control is the foundation of most biological visual systems, as well as an important component in the entire perceptual-motor system. We review some of the most basic principles of biological oculomotor systems, and explore their usefulness from both the biological and computational point of view. As an example of biomimetic oculomotor control, we present the state of our implementations and experimental results using the vestibulo-ocular-reflex and opto-kinetic-reflex paradigm.

关键词： Biomimetics Control systems Biological control systems Visual system Biology computing Motor drives Machine vision Circuit synthesis Control system synthesis Tiles

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A new estimation formula for minimum filter length of optimum FIR digital filters

A new estimation formula for minimum filter length of optimu...

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International Conference on Signal Processing Proceedings (ICSP)

作者： K. Ichige M. Iwaki R. Ishii Doctoral Program in Engineering University of Tsukuba Tsukuba Ibaraki Japan Japan Advanced Institute of Science and Technology Tatsunokuchi Ishikawa Japan Division of Electrical and Computer Engineering Yokohama National University Yokohama Japan

This paper presents an accurate estimation formula for the minimum filter length of optimum (the minimax criterion-based) FIR low-pass digital filters. The authors have proposed an accurate estimation formula for the particular case that the passband and stopband ripples are identical. Now we expand the formula for the general case. The accuracy of the proposed formula is evaluated in comparison with that of the conventional formulae. We also describe how to apply the proposed formula for the design of other types of filters.

关键词： Digital filters Finite impulse response filter Low pass filters Design optimization Algorithm design and analysis Iterative algorithms Passband Cutoff frequency Minimax techniques Iterative methods

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Using envirodaemon to search the internet for environmental information and building custom search engines

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Environmental Quality Management 1998年第3期7.0卷 103-109页

作者： Healey, Marcus J. Lewis, Jeffrey T. Samtani, Gunjan New Jersey Technical Assistance Program (NJTAP) New Jersey Institute of Technology (NJIT) United States Princeton University United States Computer Science and Information Systems United States

The Internet holds vast stores of information pertaining to pollution prevention and environmental issues, and with each day more is added. Yet, as this storehouse grows, the difficulty of finding specific information increases. This article details how EnviroDaemon was built to ease the task of finding this information and knowledge base. It automatically builds and updates a catalog of objects at pre-selected Internet sites that are related to pollution prevention. Users search for information by submitting keywords. Searches can be restricted to small subsets of the indexed sites by choosing one of five search criteria, or the entire catalog can be searched. The results are returned rapidly and are embedded in several lines of text to provide context. If the text looks promising, the user can click on a hyperlink to access the full article. Since its release in March, EnviroDaemon has seen increasing use, especially following its demonstration at the National Pollution Prevention Roundtable Conference. The authors also discuss the process of building this search engine to show interested readers how to create other environmental custom search engines. © 1998 Wiley Periodicals, Inc., A Wiley Company.

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A New Estimation Formula for Minimum Filter Length of Optimum FIR Digital Filters

A New Estimation Formula for Minimum Filter Length of Optimu...

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1998 Fourth International Conference Signal Processing

作者： Koichi Ichige Mamoru Iwaki Rokuya Ishii Doctoral Program in Engineering University of TsukubaTsukubaIbaraki 305-8573Japan Japan Advanced Institute of Science and Technology TatsunokuchiIshikawa 923-1292Japan Division of Electrical and Computer Engineering Yokohama National UniversityYokohama 240-8501Japan

This paper presents an accurate estimation formula for the minimum filter length of optimum(the minimax criterion based) FIR low-pass digital *** authors have proposed an accurate estimation formula for the particular case that the passband and stopband ripples are *** we expand the formula for the general *** accuracy of the proposed formula is evaluated in comparison with that of the conventional *** is also described how to apply the proposed formula for the design of other types of filters.

关键词： FIR A New Estimation Formula for Minimum Filter Length of Optimum FIR Digital Filters Filter

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Smart executives for autonomous spacecraft

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IEEE Intelligent Systems and Their Applications 1998年第5期13卷 56-61页

作者： Gat, Erann Pell, Barney Jet Propulsion Laboratory California Institute of Technology United States Res. Inst. for Adv. Computer Science NASA Ames Research Center United States Virginia Polytechnic Institute United States JPL MS 301-270 Pasadena CA 91109 4800 Oak Grove Dr. United States Information Systems Division NASA Ames Research Center United States NASA Ames United States Auton. Intgd. Prod. Development Team NASAs New Millenium Program United States Stanford University United States Cambridge University United Kingdom AAAI United States Mail Stop 269/2 NASA Ames Research Center Moffett Field CA 94035-1000 United States

To make spacecraft more self-reliant and less dependent on ground intervention, the authors have developed an executive (EXEC) for a new control architecture, Remote Agent. EXEC has an expanded vocabulary for commanding spacecraft, provides a wide range of capabilities at different levels of abstraction, and has a highly modular design.

关键词： Space vehicles Hardware Control systems Humans Vocabulary Propulsion NASA Face Error correction Automatic control

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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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Orthogonal schemes for bidirectional associative memories

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IEEE TRANSACTIONS ON SYSTEMS MAN AND CYBERNETICS PART B-CYBERNETICS 1997年第3期27卷 543-551页

作者： Haryono Sadananda, R Phien, HN Department of Computer Science and Information Management Program of the Asian Institute of Technology Bangkok Thailand

Two issues are addressed in this paper. Firstly, it investigates some important properties of bidirectional associative memories (BAM) and proposes an improved capacity estimate. Those properties are the encoding form of the input pattern pairs as well as their decoding, the orthogonality of the pattern pairs, the similarity of associated patterns, and the density of the pattern pairs. Secondly, it proposes an implementation approach to improve the storage capacity. The approach embraces three proposed methods, i.e., the bipolar-orthogonal augmentation, the set partition, and the combined method. Along with those methods is the construction of the set of bipolar orthogonal patterns.

关键词： associative memory bidirectional memory heteroassociative memory neural networks

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