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Optimal control of a parabolic distributed parameter system via radial basis functions

COMMUNICATIONS IN NONLINEAR SCIENCE AND NUMERICAL SIMULATION 2014年第8期19卷 2559-2567页

作者： Rad, J. A. Kazem, S. Parand, K. Shahid Beheshti Univ Fac Math Sci Dept Math Tehran 19839 Iran Amirkabir Univ Technol Dept Appl Math Fac Math & Comp Sci Tehran Iran Shahid Beheshti Univ Fac Math Sci Dept Comp Sci Tehran 19839 Iran

This paper attempts to present a meshless method to find the optimal control of a parabolic distributed parameter system with a quadratic cost functional. The method is based on radial basis functions to approximate the solution of the optimal control problem using collocation method. In this regard, different applications of RBFs are used. To this end, the numerical solutions are obtained without any mesh generation into the domain of the problems. The proposed technique is easy to implement, efficient and yields accurate results. Numerical examples are included and a comparison is made with an existing result. (C) 2013 Elsevier B. V. All rights reserved.

关键词： Optimal control distributed parameter systems Radial basis functions Collocation method Gaussian RBF Lagrange multipliers

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distributed parameter modeling and its application in parallel flow condenser optimization design based on genetic algorithm

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HVAC&R RESEARCH 2014年第3期20卷 351-361页

作者： Gu, B. Tian, Z. Liu, F. Lu, Y. Sun, X. D. Yang, L. Shanghai Jiao Tong Univ Inst Refrigerat & Cryogen Shanghai 200240 Peoples R China New Energy Vehicle Div SAIC Shanghai 201804 Peoples R China Shanghai Jiao Tong Univ Sch Mech Enginnering Shanghai 200240 Peoples R China

A parallel flow (PF) condenser with mini-channels is commonly used as a condenser in automobile air-conditioning systems. A distributed parameter model (DPM) for the PF condenser (4 passes with 15, 6, 4, and 3 tube numbers, hydraulic diameter D-h = 1.7mm) was developed based on classical correlations of heat transfer and flow friction. Experiments were performed to investigate the thermal hydraulic performance of PF condenser. The proposed DPM model was verified by experimental data. The optimal design of the PF condenser based on DPM was carried out with heat transfer and pressure drop taken as two objective functions. Genetic algorithm (GA) was utilized to solve the multi-objective problem. The hydraulic diameter and the tube numbers of each pass were chosen as design parameters. Pareto optimal solutions for the PF condenser were obtained. Analyses of variation in hydraulic diameter and tube numbers of the PF condenser are also presented.

关键词： PARALLEL-flow heat exchangers AUTOMOBILE air conditioning distributed parameter systems HEAT transfer GENETIC algorithms HYDRAULICS

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Synchronization of the Coupled distributed parameter System with Time Delay via Proportional-Spatial Derivative Control

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DISCRETE DYNAMICS IN NATURE AND SOCIETY 2014年第unknown期2014卷 1-7页

作者： Yuan, Kun Alofi, Abdulaziz Cao, Jinde Al-Mazrooei, Abdullah Elaiw, Ahmed Southeast Univ Minist Educ Sch Automat Nanjing 210096 Jiangsu Peoples R China Southeast Univ Minist Educ Key Lab Measurement & Control Complex Syst Engn Nanjing 210096 Jiangsu Peoples R China King Abdulaziz Univ Dept Math Fac Sci Jeddah 21589 Saudi Arabia

By combining parabolic partial differential equation (PDE) theory with Lyapunov technique, the synchronization is studied for a class of coupled distributed parameter systems (DPS) described by PDEs. First, based on Kronecker product and Lyapunov functional, some easy-to-test sufficient condition is given to ensure the synchronization of coupled DPS with time delay. Secondly, in the case that the whole coupled system cannot synchronize by itself, the proportional-spatial derivative (P-sD) state feedback controller is designed and applied to force the network to synchronize. The sufficient condition on the existence of synchronization controller is given in terms of a set of linear matrix inequalities. Finally, the effectiveness of the proposed control design methodology is demonstrated in numerical simulations.

关键词： distributed parameter systems TIME delay systems PARTIAL differential equations LYAPUNOV functions LINEAR matrix inequalities COMPUTER simulation

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Estimation of parameters in a distributed parameter Model for Thin Film Layered Organic Photovoltaic Cells

Estimation of Parameters in a Distributed Parameter Model fo...

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American Control Conference

作者： Rosen, I. G. Wang, C. Hu, W. Hankin, M. Lai, R. Thompson, M. E. Forrest, S. R. Univ So Calif Dept Math Modeling & Simulat Lab Los Angeles CA 90089 USA

ISBN: (纸本)9781479932740

We develop a stochastic finite element based scheme for constructing a likelihood function for the Bayesian estimation of parameters in a distributed parameter model for thin film layered organic photovoltaic cells. The scheme is based on a distributed parameter model for the propagation of the optical wave through the various layers of the cell and its conversion to an electrical current in the active layers of the device. The model consists of three components: a frequency domain wave equation based propagation model for the optical wave through the various transparent and active layers, a diffusion equation describing the dynamics of exciton density in the active layers of the device, and an output equation that describes the external quantum efficiency (EQE) of the cell. There are two parameters in the diffusion equation that have to be estimated based on measurements of EQE: the exciton diffusion length and half-life or lifetime. In this paper, a stochastic finite element based scheme that yields a probability density function (pdf) for EQE as a function of the uncertainty in exciton diffusion length and lifetime are developed. The ultimate goal is to use this pdf to construct a likelihood function as part of a Bayesian estimation scheme for the exciton diffusion length and half-life.. Numerical results involving data from an actual device are presented and discussed.

关键词： Equations Excitons Finite element analysis Mathematical model Probability density function Short-circuit currents Stochastic processes Computational methods distributed parameter systems Estimation

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Modelling of a Nonlinear distributed parameter Bioreactor via Orthogonal Collocation method

Modelling of a Nonlinear Distributed Parameter Bioreactor vi...

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International Conference on Multimedia Computing and systems (ICMCS)

作者： Rachidi, S. Karama, A. Channa, R. Cadi Ayyad Univ Fac Sci Semlalia Automat Lab Marrakech Morocco

ISBN: (纸本)9781479938247

In this paper, the aim is to develop a reduced model of a non linear distributed parameter system of hyperbolic type using the Orthogonal Collocation Method. The approach consists to approximate the original hyperbolic partial derivative equations describing the plant by a set of ordinary differential equations. The method is detailed for modeling a fixed bed bioreactor without dispertion and illustrated with various analysis showing how to select the appropriate reduced model. The dynamics of the obtained reduced model are compared to a finite difference method. Numerical simulations are included to illustrate the dynamical behaviour of the two classes of models.

关键词： Reduced model distributed parameter systems Orthogonal collocation method Fixed bed bioreactor

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Engineering Methods and Software Support for Modeling and Design of Discrete-time Control of distributed parameter systems

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EUROPEAN JOURNAL OF CONTROL 2009年第3-4期15卷 407-417页

作者： Hulko, G. Belavy, C. Meszaros, A. Bucek, P. Ondrejkovic, K. Zajicek, P. Fac Mech Engn Inst Automat Measurement & Appl Informat Bratislava 81231 Slovakia Fac Chem & Food Technol Inst Informat Engn Automat & Math Bratislava 81237 Slovakia Slovak Tech Univ Bratislava Kosice Slovakia

In this mini-tutorial some advanced engineering methods are presented for modeling and design of discrete-time control of distributed parameter systems described fir control purposes by numerical structures over complex-shape 3D definition domains along with the software package distributed parameter systems Blockset for MATLAB & Simulink - Third-Party Math Works product, inspired by the boom of numerical analysis of dynamics of machines and processes within engineering practice. The techniques offered are completed by a user-friendly web service tool, suitable for interactive solution of model control problems of distributed parameter systems via the Internet.

关键词： distributed parameter systems Discrete-time control Engineering methods Software support

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Desenvolvimento de uma ferramenta paramétrica em linguagem APDL para o cálculo da estrutura de um pórtico rolante

Desenvolvimento de uma ferramenta paramétrica em linguagem ...

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作者： Almeida, Rian Felipe Soares de Universidade Estadual Paulista

This dissertation aims to develop a parametric tool in ANSYS software programming language (APDL language) to calculate the structure of a gantry crane of central beams and reduce the time spent in hours of calculation. This paper first presents the main types of equipment as well as the own gantry cranes, and for this latter describes what are their types and what components make up its structure. Describes about the parameterization in APDL language, about the main solicitations that should be taken into consideration during the dimensioning of the structure, according to the specifications of the standard NBR8400. Present show it was developed the tool, what are their interfaces with the operator and how it works. At the end relates about gaining in saving time when using the program and analyzes the results, of tension and displacement, obtained with the simulation of a generated modelEsta dissertação tem como objetivo desenvolver uma ferramenta paramétrica em linguagem de programação de software ANSYS (linguagem APDL) para se calcular a estrutura de um pórtico rolante de vigas centrais e reduzir o tempo gasto em horas de cálculo. Neste trabalho primeiro são apresentados os principais tipos de equipamentos bem como os próprios pórticos rolantes e para estes últimos descreve quais são seus tipos e quais os componentes compõem sua estrutura Descreve sobre a parametrização em linguagem APDL, sobre as principais solicitações atuantes que devem ser levadas em consideração durante o dimensionamento da estrutura, de acordo com as especificações da norma NBR8400. Apresenta como foi desenvolvida a ferramenta, quais são suas interfaces com o operador e qual o esquema de operação da mesma. Ao final relata sobre o ganho na economia de tempo ao se utilizar o programa e analisa os resultados, de tensão e deslocamento, obtidos com a simulação de um modelo gerado

关键词： Sistemas de parâmetros distribuídos ANSYS (Programa de Computador) APDL (Linguagem de programação de computador) Esteira rolante Guindastes etc Calculo tensorial distributed parameter systems Dissertação de mestrado

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Exponential stability of linear distributed parameter systems with time-varying delays

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AUTOMATICA 2009年第1期45卷 194-201页

作者： Fridman, Emilia Orlov, Yury Tel Aviv Univ Sch Elect Engn IL-69978 Tel Aviv Israel CICESE Res Ctr Ensenada 22860 Baja California Mexico

Exponential stability analysis via the Lyapunov-Krasovskii method is extended to linear time-delay systems in a Hilbert space. The operator acting on the delayed state is supposed to be bounded. The system delay is admitted to be unknown and time-varying with an a priori given upper bound on the delay. Sufficient delay-dependent conditions for exponential stability are derived in the form of Linear Operator Inequalities (LOIs), where the decision variables are operators in the Hilbert space. Being applied to a heat equation and to a wave equation, these conditions are reduced to standard Linear Matrix Inequalities (LMIs). The proposed method is expected to provide effective tools for stability analysis and control synthesis of distributed parameter systems. (C) 2008 Elsevier Ltd. All rights reserved.

关键词： distributed parameter systems Time-varying delay Stability Lyapunov method LMI

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Disturbance rejection in a class of adaptive control laws for distributed parameter systems

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INTERNATIONAL JOURNAL OF ADAPTIVE CONTROL AND SIGNAL PROCESSING 2009年第2期23卷 166-192页

作者： Kim, Rin Y. Bentsman, Joseph Univ Illinois Dept Mech Sci & Engn Urbana IL 61801 USA

A recently introduced class of the well-posed error systems and the corresponding robust model reference adaptive control laws for the systems represented by the parabolic or the hyperbolic partial differential equations (PDEs) with the spatially varying parameters and a distributed sensing and actuation is extended to encompass the disturbance rejection capability. The disturbance is modeled as a space-time-varying signal generated by a parabolic PDE with the known parameters, a spatially varying time-invariant signal, and a space-time-varying signal with the known time variation. The case of the time-invariant disturbance model is shown to lead to a distributed adaptive PI control law, thereby making a well-posed connection to the classical finite-dimensional control structures. The numerical simulations indicate that the control laws proposed are robust with respect to the plant/reference model as well as the disturbance/disturbance observer mismatch in the boundary conditions. Copyright (c) 2008 John Wiley & Sons, Ltd.

关键词： adaptive control distributed parameter systems disturbance rejection

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Modelos para dados grupados e sensurados aplicados à área biológica: comparação usando fator de Bayes

Modelos para dados grupados e sensurados aplicados à área ...

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作者： Andrade, Sophia Lanza de Universidade Estadual Paulista

Grouped data is a particular case of survival data with interval censoring, that occurs when the observations are evaluated at the same time intervals, and is generally associated at data with a large number of draws, or draws ratio more than 25% (Chalita et al., 2002). It can be analyzed considering discrete-time and tting models at the probability of an individual fails in a certain interval, given that survived the previous one (Lawless, 2002). Among the possible models adapted to this type of data we can mention the Logistic Model and the Coxs Model. The comparison between the t of these two models can be made using the score test proposed by Colosimo et al. (2000), nonparametric Bootstrap or the Akaike Information Criterion (AIC). An alternative to these techniques, from the Bayesian point of view, is the Bayes Factor. The purpose of this study is to compare the t of the Logistic Model with the Coxs Model to grouped and censoring data using, initially, classic model selection criteria: Akaike Information Criterion (AIC), Akaike Information Criterion corrected (AICc) and Bayesian Information Criterion (BIC). After that, was used the Bayes Factor, as well as Deviance Information Criterion (DIC) and adaptations of the classic model selection criteria above mentioned, using the posteriori sample generated by a MCMC method. As an example, was used a data set related to a clinical manifestation of Chagas disease known as chagasic megacolon (Almeida, 1996)Dados grupados e um caso particular de dados de sobrevivência com censura intervalar, que ocorre quando as observações são avaliadas nos mesmos intervalos de tempo, e geralmente está associado a dados com grande número de empates, ou seja, quando a proporção de empates e maior que 25% (Chalita et al., 2002), e podem desta forma ser analisados considerando o tempo discreto e ajustando-se modelos a probabilidade do indivíduo falhar em um certo intervalo, dado que sobreviveu ao intervalo anterior (Lawless, 2002). Dentre

关键词： Análise de sobrevivência (Biometria) Teoria bayesiana de decisão estatistica Estatística Sistemas de parâmetros distribuídos distributed parameter systems Dissertação de mestrado

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