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63rd Annual Meeting of the Institute of Navigation 2007

作者： Miller, Mikel Nguyen, Thao Yang, Chun Blasch, Erik Air Force Research Lab. MNG Air Force Research Lab. SNRN Sigtem Technology Inc. Air Force Research Lab. SNAA Department of Electrical and Computer Engineering Miami University of Ohio Advanced Guidance Division Munitions Directorate Air Force Research Laboratory Eglin AFB FL Department of EE AFIT Miami University of Ohio ION RTN IEEE AIAA Assessment and Integration Branch Sensors Directorate Air Force Research Laboratory WPAFB OH AFIT SPIE Wright-Patterson AFB OH Reference Systems Branch Sensors Directorate Air Force Research Laboratory WPAFB OH

ISBN: (纸本)1604232862

Three integration schemes, namely, coherent, noncoherent, and semi-coherent integration, and their variants are described in this paper for signal detection and tracking in such applications as pulsed Doppler radar and GPS receiver. We adopt a unified approach to present such integration schemes as best approximations to the likelihood ratio test (LRT) when the signal models are partially known to different extents. Formulas for the conditional probability density functions (pdfs) of the sufficient statistic under alternative hypotheses as well as the probability of detection (Pd) and probability of false alarm (Pfa) are given. Integration improvement factors and integration losses are then formulated. Connections of the semi-coherent integration scheme to the cyclic autocorrelation function, the discrete-time Wigner-Ville transform, and the radar ambiguity function are also outlined. Although most of the results are available in the literature, they are scattered in different textbooks and research papers. By presenting them in a cohesive and concise manner, the paper can serve as (1) an introductory material with key references for those who would like to study the subject further, (2) a quick reference for those who would like to compare these integration schemes, and (3) an integrated approach under varying conditions. Simulation results are presented to compare these integration schemes in terms of detection performance (P d and Pfa) as a function of signal to noise ratio (SNR) and integration interval under two operating conditions. One is for a signal with constant Doppler frequency and the other is for a linear frequency modulation signal (i.e., a chirp signal). We show the curves of the input SNR required under different chirp rates so as to maintain the same detection performance, the resulting LRTs for the different approaches, as well as simulated comparisons between trade-offs of Pd versus SNR.

关键词： Signal receivers

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Quality Evaluation in Flexible Machining systems: A Flexible Fixture Case Study

Quality Evaluation in Flexible Machining Systems: A Flexible...

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IEEE International Conference on Robotics and Automation (ICRA)

作者： Jingshan Li Ningjian Huang Department of Electrical and Computer Engineering and Center for Manufacturing University of Kentucky Lexington KY USA Manufacturing Systems Research Lab General Motors Research and Development Center Warren MI USA

Most of the studies in flexible manufacturing systems address the issues of flexibility, productivity, cost, etc. The impact of flexible lines on product quality is less studied. This paper presents a quantitative model based on Markov chain analysis to evaluate quality performance of a flexible machining system. A case study of flexible fixture is provided to illustrate the applicability of the method.

关键词： Machining Fixtures Flexible manufacturing systems Productivity Costs Manufacturing systems Performance analysis Production systems Automotive engineering Machinery production industries

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System of systems approach to threat detection and integration of heterogeneous independently operable systems

System of systems approach to threat detection and integrati...

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2007 IEEE International Conference on systems, Man, and Cybernetics, SMC 2007

作者： Sahin, Ferat Sridhar, Prasanna Horan, Ben Raghavan, Vikraman Jamshidi, Mo IEEE Rochester Institute of Technology Rochester NY 14623 United States Department of Electrical and Computer Engineering University of Texas San Antonio San Antonio TX 78249 University of Texas San Antonio San Antonio TX 78249 Intelligent Systems Research Lab. Deakin University Geelong VIC 3217 Australia

ISBN: (纸本)1424409918

This paper presents a system of systems approach to threat detection through integration of heterogeneous independently operable systems. The approach is presented on a realistic situation where a human-controlled base robot, swarm robot(s), and sensors work together to obtain a decision about a possible threat in the environment. The base robot is remotely operated by a human using a haptic control system. The swarm robot(s) are autonomous and can accept directives from the base robot. Finally, sensors directly communicate with (report to) the base robot. In this scenario, heterogeneous systems and human interact in a system of systems architecture. With the inclusion of human expert and sensor verification of swarm robots, the system can successfully perform the threat detection and reduce the false alarms. Finally, a system of systems simulation framework including a base robot, a swarm robot, and two sensors is presented in addition to an experimental evaluation of the proposed SoS architecture. © 2007 IEEE.

关键词： Intrusion detection

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MEMS ROTARY ACTUATOR USING AN INTEGRATED BALL BEARING AND AIR TURBINE

MEMS ROTARY ACTUATOR USING AN INTEGRATED BALL BEARING AND AI...

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TRANSDUCERS 2007 - 2007 International Solid-State Sensors, Actuators and Microsystems Conference, Volume 3 of 5

作者： C. M. Waits N. R. Jankowski B. Geil R. Ghodssi US Army Research Laboratory Adelphi MD USA MEMS Sensors and Actuators Lab (MSAL) Department of Electrical and Computer Engineering Institute for Systems Research (ISR) University of Maryland College Park MD USA

The first silicon air-driven rotary actuation mechanism based on encapsulated ball bearings is reported. The method of integrating a silicon air turbine with a ball bearing support mechanism has been developed for silicon turbomachinery and tribological investigations. Rotational speeds up to 37,000 rpm and continuous operation longer than 24 hours were measured. Qualitative analysis is also presented, shedding light on silicon/ball wear and methods for increasing bearing lifetime and speeds.

关键词： Microball Bearings Microturbine MEMS Tribology

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Time-varying port-representation of dissipative structures with gauge transformations

Time-varying port-representation of dissipative structures w...

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European Control Conference (ECC)

作者： Gou Nishida Masaki Yamakita Zhi-wei Luo RIKEN(The Institute of Physical and Chemical Research) Environment Adaptive Robotic Systems Lab Nagoya Aichi JAPAN Department of Mechanical and Control Engineering RIKEN BMC Meguro-ku Tokyo JAPAN Department of Computer and Systems Engineering RIKEN BMC Kobe Hyogo JAPAN

A distributed-port-Hamiltonian system is a generalized model for passivity-based controls. The system representation has been extended to an infinite-dimensional conservative system derived from variational calculus, which is called a field-port-Lagrangian system. A lot of practical systems for control engineering include dissipative elements; however such a non-conservative structure usually cannot be defined by a variational problem. This paper shows that a system with the dissipative structure can be defined as a time-varying fieldport-Lagrangian system by a gauge transformation. First, we show that the gauge transformation generates a time-dependent Lagrangian density functional that introduces the time-varying port-representation. Next, we present that a class of dissipative systems can be identified with a conservative system possessing an internal irreversible energy flow. Finally, we illustrate an equation of elastic films with viscosity damping with the time-varying port-representation.

关键词： Equations Vectors Viscosity Time-varying systems Mathematical model Damping Indexes

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A multidiscipline and multi-rate modeling framework for planar solid-oxide fuel cell based power-conditioning system for vehicular APU

A multidiscipline and multi-rate modeling framework for plan...

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Summer computer Simulation Conference 2007, SCSC 2007, Part of the 2007 Summer Simulation Multiconference, SummerSim 2007

作者： Mazumder, Sudip K. Pradhan, Sanjaya Hartvigsen, Joseph Rancruel, Diego Von Spakovsky, Michael R. Khaleel, Moe Department of Electrical and Computer Eng Lab for Energy and Switching-electronics Systems University of Illinois Chicago United States Philips United States SOFC and Hydrogen Technologies Ceramatec United States New Product Introduction GE Power Generation Technology United States Department of Mechanical Engineering Center for Energy Systems Research Virginia Polytechnic Institute and State University United States Computational Sciences and Mathematics Division Pacific Northwest National Laboratory United States

ISBN: (纸本)9781622763580

We develop a numerical modeling framework for planar solid-oxide fuel cell (PSOFC) based vehicular auxiliary power unit (APU). The power-conditioning system (PCS) model comprises the comprehensive transient models of PSOFC, balance-of-plant and power-electronics subsystems (i.e., BOPS and PES, respectively), and application load (AL). It can be used for resolving the interactions among PSOFC, BOPS, PES, and AL, control design and system optimization, and fuel-cell durability studies. The PCS model has several key properties including the following: i) it can predict simultaneously predict spatial as well as temporal dynamics;ii) it has two levels of abstraction: comprehensive (for detailed dynamics) and reduced-order (for fast simulation);and iii) the fastsimulation model can be implemented completely in Simulink/Matlab environment, thereby significantly reducing the cost as well as time and provides the avenue for real-time simulation and integration with vehicular power-train models using the widely used ADVISOR. We compared the computational overhead and accuracy of the fast-simulation and comprehensive models and the show significant savings in time obtained using the former without compromising accuracy.

关键词： Simulink

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CHITOSAN-MEDIATED BIOMEMS PLATFORM FOR OPTICAL SENSING

CHITOSAN-MEDIATED BIOMEMS PLATFORM FOR OPTICAL SENSING

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TRANSDUCERS 2007 - 2007 International Solid-State Sensors, Actuators and Microsystems Conference, Volume 3 of 5

作者： V. Badilita I. Shamim H. Yi S. T. Koev K. Gerasopoulos R. Ghodssi MEMS Sensors and Actuators Lab (MSAL) Department of Electrical and Computer Engineering Institute for Systems Research (ISR) University of Maryland College Park MD USA Department of Chemical and Biological Engineering Tufts University Medford MA USA

We present an optical BioMEMS sensor with chitosan-mediated, spatially-selective functionalization of a microfluidic channel sidewall with single stranded probe DNA (ssDNA). High-contrast optical sensing of hybridization using integrated optical waveguides and fluorescently-tagged matching versus mismatching DNA sequences is demonstrated. The collected peak emission signal corresponding to matching DNA sequences (4μM) exceeds the peak emission signal corresponding to mismatching DNA sequences (8μM) by a factor of 50. We demonstrate that the device is robust and reusable by exposing it to two successive cycles of denaturation/re-hybridization, each time recovering the initial sensitivity and specificity.

关键词： DNA hybridization Integrated waveguides Microfluidics Chitosan

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Semantic web search for e-government: The case study of intrastat

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Journal of Internet Technology 2007年第4期8卷 457-468页

作者： Markellos, Konstantinos Sakkopoulos, Evangelos Sirmakessis, Spiros Tsakalidis, Athanasios Research Academic Computer Technology Institute Department of Computer Engineering and Informatics University of Patras Greece Department of Applied Informatics in Administration and Economics Technological Educational Institutional of Messolongi University of Patras Greece Department of Computer Engineering and Informatics University of Patras Greece Department of Applied Informatics in Administration and Economy TEI of Messolongi Data Bases and Information Systems Sector E-business and Human Computer Interaction Lab.

The field of Statistics is a conceptually rich domain where information is complex, huge in volume, and highly valuable and critical for Governmental institutes. The daily production of statistical information increases exponentially worldwide, making the processing of all this information a very difficult and time - consuming task. Therefore, efficient search, filtering and browsing techniques are needed to access and process statistical data in an effective way. We present semantically enhanced search approach to enhance e-Govemment searching services. We evaluate our proposals on the case of Intrastat, that is the method of collecting information and producing statistics on the export and import of goods between Member States of the European Union (EU), providing added - value web search services. We employ Semantic Web technologies to create an intelligent search engine based on modeling the systems' electronic catalogue using the OWL ontology language, combined with AJAX techniques for usability richness and responsiveness. We present a search tool based on these technologies, that consists of a) our novel ontology for the EU Combined Nomenclature codes serving as a knowledge base, b)a semantically enhanced search and recommendation module that improves the quality of the results and c) a "Search as you type" visualization and navigation module to provide a usable interface to be used in navigation and search.

关键词： Semantic Web

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Evaluation, selection, and application of model-based diagnosis tools and approaches

Evaluation, selection, and application of model-based diagno...

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2007 AIAA InfoTech at Aerospace Conference

作者： Poll, Scott Patterson-Hine, Ann Camisa, Joe Nishikawa, David Spirkovska, Lilly Garcia, David Hall, David Neukom, Christian Sweet, Adam Yentus, Serge Lee, Charles Ossenfort, John Mengshoel, Ole J. Roychoudhury, Indranil Daigle, Matthew Biswas, Gautam Koutsoukos, Xenofon Lutz, Robyn NASA Ames Research Center Moffett Field CA 94035 United States QSS Group Inc. Perot Systems Government Services Moffett Field CA 94035 United States SAIC Moffett Field CA 94035 United States RIACS Moffett Field CA 94035 United States Vanderbilt University Nashville TN 37235 United States Jet Propulsion Lab. Caltech. Iowa State University Ames IA 50011 United States ADAPT Discovery and Systems Health MS 269-1 United States Discovery and Systems Health MS 269-4 United States Electronic Systems and Controls Branch MS 213-2 United States Department of Electrical Engineering and Computer Science Institute for Software Integrated Systems United States Department of Computer Science

ISBN: (纸本)1563478935

Model-based approaches have proven fruitful in the design and implementation of intelligent systems that provide automated diagnostic functions. A wide variety of models are used in these approaches to represent the particular domain knowledge, including analytic state-based models, input-output transfer function models, fault propagation models, and qualitative and quantitative physics-based models. Diagnostic applications are built around three main steps: observation, comparison, and diagnosis. If the modeling begins in the early stages of system development, engineering models such as fault propagation models can be used for testability analysis to aid definition and evaluation of instrumentation suites for observation of system behavior. Analytical models can be used in the design of monitoring algorithms that process observations to provide information for the second step in the process, comparison of expected behavior of the system to actual measured behavior. In the final diagnostic step, reasoning about the results of the comparison can be performed in a variety of ways, such as dependency matrices, graph propagation, constraint propagation, and state estimation. Realistic empirical evaluation and comparison of these approaches is often hampered by a lack of standard data sets and suitable testbeds. In this paper we describe the Advanced Diagnostics and Prognostics Testbed (ADAPT) at NASA Ames research Center. The purpose of the testbed is to measure, evaluate, and mature diagnostic and prognostic health management technologies. This paper describes the testbed's hardware, software architecture, and concept of operations. A simulation testbed that accompanies ADAPT, and some of the diagnostic and decision support approaches being investigated are also discussed.

关键词： Intelligent systems

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Generation of multi-channel short-pulse sources using nonlinear optical loop mirror based on photonic crystal fiber

Generation of multi-channel short-pulse sources using nonlin...

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OFC/NFOEC 2007 - Optical Fiber Communication and the National Fiber Optic Engineers Conference 2007

作者： Dong, Yi Li, Zhaohui Yu, Changyuan Wen, Yang Jing Wang, Yixin Lu, Chao Hu, Weisheng Cheng, Tee Hiang State Key Lab of Advanced Optical Communication Systems and Networks Shanghai Jiao Tong University 800 Dongchuan Rd. Shanghai 200240 China School of Electrical and Electronic Engineering Nanyang Technological University Singapore 639798 Singapore Institutes for Infocomm Research A STAR 21 Heng Mui Keng Terrace Singapore 119613 Singapore Dept. of Electrical and Computer Engineering National University of Singapore 4 Engineering Dr. 3 Singapore 117576 Singapore Department of Electronic and Information Engineering Hong Kong Polytechnic University Hong Kong Hong Kong

Fourteen C+L-band synchronized multi-channel short pulse sources are generated based on XPM and FWM effects in nonlinear optical loop mirror. Walk-off effect is reduced effectively by using 10m high nonlinear dispersi... 详细信息

ISBN: (纸本)1557528314

关键词： Optical systems

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