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43rd AIAA/ASME/SAE/ASEE Joint Propulsion Conference

作者： Litchford, Ron J. Foote, John P. Ramachandran, Narayanan Wang, Ten-See Anghaie, Samim NASA Marshall Space Flight Center Thermal/Combustion Devices Propulsion System Dept. AIAA Thermal Analysis Propulsion Systems Dept. Thermal/Combustion Analysis Propulsion System Dept. Department of Nuclear and Radiological Engineering

ISBN: (纸本)1563479036

A preliminary design study is presented for a non-nuclear test facility which uses ohmic heating to replicate the thermal hydraulic characteristics of solid core nuclear reactor fuel element passages. The basis for this testing capability is a recently commissioned nuclear thermal rocket environments simulator, which uses a high-power, multi-gas, wall-stabilized constricted arc-heater to produce high-temperature pressurized hydrogen flows representative of reactor core environments, excepting radiation effects. Initially, the baseline test fixture for this non-nuclear environments simulator was configured for long duration hot hydrogen exposure of small cylindrical material specimens as a low cost means of evaluating material compatibility. It became evident, however, that additional functionality enhancements were needed to permit a critical examination of thermal hydraulic effects in fuel element passages. Thus, a design configuration was conceived whereby a short tubular material specimen, representing a fuel element passage segment, is surrounded by a backside resistive tungsten heater element and mounted within a selfcontained module that inserts directly into the baseline test fixture assembly. With this configuration, it becomes possible to create an inward directed radial thermal gradient within the tubular material specimen such that the wall-to-gas heat flux characteristics of a typical fuel element passage are effectively simulated. The results of a preliminary engineering study for this innovative concept are fully summarized, including high-fidelity multi-physics thermal hydraulic simulations and detailed design features.

关键词： Flight simulators

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Optimal code and carrier tracking loop design for Galileo BOC(1, 1)

Optimal code and carrier tracking loop design for Galileo BO...

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20th International Technical Meeting of the Satellite Division of The Institute of Navigation 2007 ION GNSS 2007

作者： Jee, Gyu-In Im, Sung-Hyuck Lee, Byung-Hyun Navigation and Control System Lab. Dept. of Electronics Engineering Konkuk University Seoul 143-701 Korea Republic of

ISBN: (纸本)9781605600697

In this paper we deal with the Galileo BOC(1, 1) signal tracking loop optimization. It is shown that the DLL/PLL/FLL design can be shown as an optimal controller design problem. A state space model is derived for Galileo signal tracking problem. Based on this a combined DLL/PLL/FLL is design by use of the Linear Quadratic Gaussian (LQG) optimal control theory. The LQG loop filter is a regulator. It derives the total code and phase tracking errors as small as possible and results in the minimum mean squared error control performance. Therefore we can optimally design a combined receiver loop filters for code, carrier, and frequency tracking. This could results in an improved tracking performance over the conventionally, separately and independently designed tracking loops. The designed tracking loops are applied to real Galileo BOC(1, 1) signal received from the GlOVE-A satellite. Signal processing results showed improved tracking performance of the LQG based tracking loops over the conventional approach.

关键词： Signal processing

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Texture retrieval based on a non-parametric measure for multivariate distributions 07

Texture retrieval based on a non-parametric measure for mult...

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6th ACM International Conference on Image and Video Retrieval, CIVR 2007

作者： Pothos, Vasileios K. Theoharatos, Christos Economou, George Ifantis, Apostolos Electronics Laboratory Dept. of Physics University of Patras Patras 26500 Greece Control System and Signal Laboratory Dept. of Electrical Engineering Technological Institute of Patras Patras 26334 Greece

ISBN: (纸本)1595937331

In the present study, an efficient strategy for retrieving texture images from large texture databases is introduced and studied within a distributional-statistical framework. Our approach incorporates the multivariate Wald-Wolfowitz test (WW-test), a non-parametric statistical test that measures the similarity between two different sets of multivariate data, which is utilized here for comparing texture distributions. By summarizing the texture information using standard feature extraction methodologies, the similarity measure provides a comprehensive estimate of the match between different images based on graph theory. The proposed "distributional metric" is shown to handle efficiently the texture space dimensionality and the limited sample size drawn from a given image. The experimental results, from the application on a typical texture database, clearly demonstrate the effectiveness of our approach over other texture distribution (dis)similarity metrics. In addition, its performance is used to evaluate several approaches for texture representation. Even though the classification results are obtained on grayscale images, a direct extension to color-based ones can be straightforward. Copyright 2007 ACM.

关键词： Multivariable systems

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Monitored unit and system governing response to large frequency changes following loss of generation in normal operation system

Monitored unit and system governing response to large freque...

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IEEE-Power-engineering-Society General Meeting

作者： Allen, E. H. Ingleson, J. W. Schulz, R. P. IEEE Events Analysis and Information Exchange North American Electric Reliability Council (NERC) New York Independent System Operator Inc. (NYISO) PSRC's Relaying Practices Subcommittee System Planning Dept. American Electric Power CIGRE IEEE Power Engineering Society

ISBN: (纸本)9781424412969

Two electric utility control areas independently adapted existing system data collection software to capture the response of the units within their several utilities' generation before, during, and after the loss of large blocks of generation [ranging from 1000 MW to 2200 MW] during periods of otherwise normal operation. These measurements are essentially unannounced tests of the governing response of the units and of the system response to frequency changes. The results have been examined with knowledge of the primary frequency control systems to provide evidence of the effects of the primary frequency control systems. The two operating areas were AEP (American Electric Power) and NYISO (New York Independent\system Operator);both are members of the US-Canadian Eastern Interconnection (EI). AEP was and is a member of the NERC (North American Reliability Council) and of NERC's ECAR (East Central Area Reliability Council). NYISO was and is a member of NERC and of NERC's NPCC (Northeast Power Coordinating Council). At the time of the measurements AEP had approximately 24,000 MW of installed generation, and NYISO had approximately 33,000 MW of installed generation. This paper is one of several that have evolved from the work of the IEEE PES Task Force on Large Interconnected Power system Response to Generation Governing.

关键词： power system planning power system operations primary frequency regulation measurements

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A robust gender and age estimation under varying facial pose

IEEJ Transactions on Electronics, Information and Systems

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IEEJ Transactions on Electronics, Information and systems 2007年第7期127卷 1022-1029+7页

作者： Takimoto, Hironori Mitsukura, Yasue Fukumi, Minoru Akamatsu, Norio Dept. of Control Engineering Sasebo National College of Technology Japan Graduate School of Bio-Applications and System Enginnering Tokyo University of Agriculture and Technology Japan Dept. of Information Science and Intteligent Syst. Faculty of Eng. University of Tokushima Japan Sasebo National College of Technology Japan Tokyo University of Agriculture and Technology Japan University of Tokushima Japan

This paper presents a method for gender and age estimation which is robust for facial pose changing. We propose a feature point detection method which is the Adapted Retinal Sampling Method (ARSM), and a feature extraction method. A basic concept of the ARSM is to add knowledge about the facial structure into the Retinal Sampling Method. In this method, feature points are detected based on 7 points corresponding to facial organ from face image. The reason why we used 7 points to basis of feature point detection is that facial organ is conspicuous in facial region, and it is comparatively easy to extract. As features which is robust for facial pose changing, a skin texture, a hue and a gabor jet are used for the gender and age estimation. For classification of gender and estimation of seriate age, we use a multi-layered neural network. Moreover, we examine the left-right symmetric property of the face concerning gender and age estimation by the proposed method.

关键词： Feature extraction

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Parametrization of MIMO multi-controller schemes for bumpless switching 9

Parametrization of MIMO multi-controller schemes for bumples...

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2007 9th European control Conference, ECC 2007

作者： Yame, Joseph Kinnaert, Michel Delwiche, Thomas CRAN-UMR 7039 CNRS Université Henri Poincaré Nancy i Vandoeuvre-les-NancyF-54506 France Dept. of Control Engineering and System Analysis Université Libre de Bruxelles 50 Av. F. D. Roosevelt BrusselsB-1050 Belgium

ISBN: (纸本)9783952417386

In this paper the realization and implementation of a multi-controller scheme made of a finite set of linear multiple-input-multiple-output controllers, possibly having different state dimensions, is considered. The problem of bumpless switching between the active controller acting in closed-loop and another controller in the set of controllers waiting to take over the control loop is addressed. A non minimal parametrization of the set of controllers such that all controllers share the same state variables is presented, and it is shown that such a parametrization guarantees bumpless switching between any two controllers within the controller set. © 2007 EUCA.

关键词： controllers

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Vector backstepping design for flight control

Vector backstepping design for flight control

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AIAA Guidance, Navigation, and control Conference 2007

作者： Härkegård, Ola Glad, Torkel Saab AB SE-581 88 Linköping Sweden Linköping University SE-581 83 Linköping Sweden Flight Control System Saab Aerosystems Sweden Division of Automatic Control Dept. of Electrical Engineering Sweden

ISBN: (纸本)1563479044

A backstepping design for an aircraft described by rigid body dynamics is proposed. The system states are the unit velocity vector and the angular velocity in a body-fixed coordinate system. The result can be viewed as a multi-variable controller for angle of attack, sideslip angle, and velocity vector roll rate. The backstepping design is performed on the rigid body dynamics described on vector form. The resulting controller achieves convergence to a desired state from almost all starting points. Guidelines are given for tuning the controller to affect the characteristics of the short period mode, the roll mode and the dutch roll mode. A coupled high angle of attack, high roll rate maneuver is simulated using a simplified aircraft model to illustrate the design.

关键词： Flight control systems

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Parametrization of MIMO multi-controller schemes for bumpless switching

Parametrization of MIMO multi-controller schemes for bumples...

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European control Conference (ECC)

作者： Joseph Yamé Michel Kinnaert Thomas Delwiche CRAN-UMR 7039 CNRS Université Henri Poincaré Vandoeuvre-les-Nancy France Dept. of Control Engineering and System Analysis Université Libre de Bruxelles Brussels Belgium

关键词： Switches Closed loop systems Trajectory Process control Transient analysis Polynomials

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Electro-thermo-hydrodynamic control of solidification of binary mixtures

Electro-thermo-hydrodynamic control of solidification of bin...

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作者： Colaço, Marcelo J. Dulikravich, George S. Dept. of Mechanical and Materials Engineering Military Institute of Engineering Pc. Gen. Tiburcio 80 Rio de Janeiro RJ 22290-270 Brazil Dept. of Mechanical and Materials Engineering Multidisciplinary Analysis Inverse Design Robust Optimization and Control - MAIDROC Lab. Florida International University 10555 West Flagler St. Miami FL 33174 United States

ISBN: (纸本)9781615676248

In this paper we apply a multilevel hybrid optimization algorithm based on a response surface methodology to control the solidification process of a double-diffusive fluid flow, during the phase-change, in the presence of electric and thermal body forces. The problem consists of a rectangular cavity subjected to a thermosolutal flow containing electrically charged particles where the patterns of the isothermal fields for the solute are prescribed. The optimization problem is formulated in terms of the electric and thermal boundary conditions that must induce such prescribed temperature profile. Thus, it is essentially an inverse problem that is solved by determining the appropriate electric and thermal boundary conditions. The electro-thermo-hydrodynamics analysis including solidification was performed using our implicit algorithm on a fixed structured grid. The optimizer is based on several deterministic and evolutionary algorithms with automatic switching among them, combining the best features of each one. The response surface methodology uses several radial basis function interpolants in order to significantly reduce the high computational cost involved during the optimization process of the electric and thermal boundary conditions. The entire numerical simulation was performed on our 96-processor Opteron based parallel computer running Linux and MPI.

关键词： Boundary conditions

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A new smart power module for low power motor drives

A new smart power module for low power motor drives

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7th Internatonal Conference on Power Electronics, ICPE'07

作者： Kwon, Tae-Sung Song, Jun-Ho Lee, Jun-Bae Paek, Seung-Han Yong, Sung-Il Motion Control System Team Functional Power Group Fairchild Semiconductor 82-3 Dodang-Dong Wonmi-Gu Bucheon-Si Gyeonggi-Do Korea Republic of Dept. of Electrical Engineering Hanyang University 133-791 Haengdang-dong Sungdong-Gu Seoul Korea Republic of

ISBN: (纸本)9781424418725

This paper introduces a new Motion-SPM (Smart Power Modules)module in Single In-line Package(SIP), which is a fully optimized intelligent integrated IGBT inverter module for up to 1kW low power motor drive applications. This module offers a sophisticated, integrated solution and tremendous design flexibilty. It also takes advantage of pliability for the arrangement of heat-sink due to two types of lead forms. It utilizes non-punch-through (NPT) IGBT with a fast recovery diode and highly integrated building block, which features built-in HVICs and a gate driver that offer more simplicity and compactness leading to a reduced costs and high reliability of the entire system. This module also provides technical advantages such as the good thermal performances through IMS (Insulated Metal Substrate), the high latch immunity. This paper provides an overall description of the Motion-SPM in SIP as well as actual application issues such as electrical characteristics, circuit configurations and power ratings. © 2008 IEEE.

关键词： Insulated gate bipolar transistors (IGBT)

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