Search results for "Mathematica"

showing 10 items of 7971 documents

Fractional-order theory of thermoelasticicty. I: Generalization of the Fourier equation

2018

The paper deals with the generalization of Fourier-type relations in the context of fractional-order calculus. The instantaneous temperature-flux equation of the Fourier-type diffusion is generalized, introducing a self-similar, fractal-type mass clustering at the micro scale. In this setting, the resulting conduction equation at the macro scale yields a Caputo's fractional derivative with order [0,1] of temperature gradient that generalizes the Fourier conduction equation. The order of the fractional-derivative has been related to the fractal assembly of the microstructure and some preliminary observations about the thermodynamical restrictions of the coefficients and the state functions r…

Uses of trigonometryGeneralization01 natural sciences010305 fluids & plasmasScreened Poisson equationsymbols.namesakeFractional operators0103 physical sciencesFractional Fourier equationMechanics of Material010306 general physicsFourier seriesMathematicsFourier transform on finite groupsEntropy functionsHill differential equationPartial differential equationMechanical EngineeringFourier inversion theoremMathematical analysisTemperature evolutionMechanics of MaterialssymbolsFractional operatorSettore ICAR/08 - Scienza Delle CostruzioniEntropy function
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Consistency of Probability Decision Rules and Its Inference in Probability Decision Table

2012

In most synthesis evaluation systems and decision-making systems, data are represented by objects and attributes of objects with a degree of belief. Formally, these data can be abstracted by the form (objects; attributes; P), wherePrepresents a kind degree of belief between objects and attributes, such that,Pis a basic probability assignment. In the paper, we provide a kind of probability information system to describe these data and then employ rough sets theory to extract probability decision rules. By extension of Dempster-Shafer evidence theory, we can get probabilities of antecedents and conclusion of probability decision rules. Furthermore, we analyze the consistency of probability de…

VDP::Mathematics and natural science: 400::Mathematics: 410::Applied mathematics: 413Article Subjectbusiness.industrylcsh:MathematicsGeneral MathematicsVDP::Technology: 500Mathematical statisticsGeneral EngineeringApplied probabilityProbability and statisticsDecision rulelcsh:QA1-939Bayesian inferenceImprecise probabilitylcsh:TA1-2040Fiducial inferenceInfluence diagramArtificial intelligencelcsh:Engineering (General). Civil engineering (General)businessMathematicsMathematical Problems in Engineering
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Approximate analytic and numerical solutions to Lane-Emden equation via fuzzy modeling method

2012

Published version in the journal: Mathematical Problems in Engineering. Also available from the publisher: http://dx.doi.org/10.1155/2012/259494 A novel algorithm, called variable weight fuzzy marginal linearization VWFML method, is proposed. Thismethod can supply approximate analytic and numerical solutions to Lane-Emden equations. And it is easy to be implemented and extended for solving other nonlinear differential equations. Numerical examples are included to demonstrate the validity and applicability of the developed technique.

VDP::Mathematics and natural science: 400::Mathematics: 410::Applied mathematics: 413Article Subjectlcsh:MathematicsGeneral MathematicsMathematical analysisGeneral EngineeringOrder of accuracylcsh:QA1-939Fuzzy logiclcsh:TA1-2040LinearizationAnalytic element methodVariable weightLane–Emden equationlcsh:Engineering (General). Civil engineering (General)MathematicsNumerical stabilityNumerical partial differential equations
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Development of lumped-parameter mathematical models for a vehicle localized impact

2011

Published version of an article in the journal:Journal of Mechanical Science and Technology. Also available from the publisher on SpringerLink: http://dx.doi.org/10.1007/s12206-011-0505-x In this paper, we propose a method of modeling for vehicle crash systems based on viscous and elastic properties of the materials. This paper covers an influence of different arrangement of spring and damper on the models’ response. Differences in simulating vehicle-torigid barrier collision and vehicle-to-pole collision are explained. Comparison of the models obtained from wideband (unfiltered) acceleration and filtered acceleration is done. At the end we propose a model which is suitable for localized co…

VDP::Mathematics and natural science: 400::Mathematics: 410::Applied mathematics: 413EngineeringMathematical modelbusiness.industryMechanical EngineeringVDP::Technology: 500::Mechanical engineering: 570MechanicsCollisionDamperAccelerationDevelopment (topology)Mechanics of MaterialsSpring (device)WidebandbusinessMaterial propertiesSimulationJournal of Mechanical Science and Technology
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Further results on mathematical models of vehicle localized impact

2010

Accepted version of an article published by IEEE. (c) 2010 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other users, including reprinting/ republishing this material for advertising or promotional purposes, creating new collective works for resale or redistribution to servers or lists, or reuse of any copyrighted components of this work in other works Published version:http://dx.doi.org/10.1109/ISSCAA.2010.5634041 In this paper, we propose a method of modeling for vehicle crash systems based on viscous and elastic properties of the materials. This paper covers an influence of different arrangement of spring and damper on the models? respons…

VDP::Mathematics and natural science: 400::Mathematics: 410::Applied mathematics: 413EngineeringMathematical modelbusiness.industryVibration controlStructural engineeringSolid modelingMechanicsCollisionDamperVehicle dynamicsShock absorberVDP::Technology: 500::Materials science and engineering: 520Widebandbusiness2010 3rd International Symposium on Systems and Control in Aeronautics and Astronautics
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Data-Driven Adaptive Observer for Fault Diagnosis

2012

Published version of an article from the journal: Mathematical Problems in Engineering. Also available from the publisher:http://dx.doi.org/10.1155/2012/832836 This paper presents an approach for data-driven design of fault diagnosis system. The proposed fault diagnosis scheme consists of an adaptive residual generator and a bank of isolation observers, whose parameters are directly identified from the process data without identification of complete process model. To deal with normal variations in the process, the parameters of residual generator are online updated by standard adaptive technique to achieve reliable fault detection performance. After a fault is successfully detected, the iso…

VDP::Mathematics and natural science: 400::Mathematics: 410::Applied mathematics: 413EngineeringMathematical problemArticle Subjectbusiness.industryGeneral Mathematicslcsh:MathematicsVDP::Technology: 500General EngineeringControl engineeringFault (power engineering)lcsh:QA1-939Adaptive observerData-drivenStuck-at faultlcsh:TA1-2040Fault modelbusinesslcsh:Engineering (General). Civil engineering (General)Mathematical Problems in Engineering
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A computational method to optimal control of a wind turbine system using wavelets

2011

Author's version of a chapter in the book: Proceedings of the IEEE International Syposium on Computer-Aided Control System Design (2011). Also avaliable from the publisher at: http://dx.doi.org/10.1109/CACSD.2011.6044551 This paper deals with a computational optimization approach to the problem of state-feedback control design for a wind turbine system. The first step of the study is to develop a reduced order model for the system by considering the most important physical phenomena of aerodynamics and structural dynamics. Moreover, the behavior of the system can be influenced by the coupled dynamics between the tower motions and the blade pitch and turbine speed which can cause instabiliti…

VDP::Mathematics and natural science: 400::Mathematics: 410::Applied mathematics: 413Engineeringbusiness.industryBlade pitchWavelet transformAerodynamicsOptimal controlTurbineSystem dynamicsAlgebraic equationWaveletControl theoryaerodynamics blades equations mathematical model optimal control poles and towers wind turbinesVDP::Technology: 500::Materials science and engineering: 520business
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Observer-Based Stabilization of Stochastic Systems with Limited Communication

2012

Published version of an article in the journal: Mathematical Problems in Engineering. Also available from Hindawi: http://dx.doi.org/10.1155/2012/781542 Open Access This paper studies the problem of observer-based stabilization of stochastic nonlinear systems with limited communication. A communication channel exists between the output of the plant and the input of the dynamic controller, which is considered network-induced delays, data packet dropouts, and measurement quantization. A new stability criterion is derived for the stochastic nonlinear system by using the Lyapunov functional approach. Based on this, the design procedure of observer-based controller is presented,which ensures asy…

VDP::Mathematics and natural science: 400::Mathematics: 410::Applied mathematics: 413Mathematical optimizationObserver (quantum physics)Article SubjectComputer scienceStability criterionGeneral Mathematicslimited communicationSeparation principleExponential stabilityControl theorydesign proceduredynamic controllerNetwork packetlcsh:MathematicsQuantization (signal processing)VDP::Technology: 500::Mechanical engineering: 570General EngineeringIllustrative examplesObserver (special relativity)lcsh:QA1-939Lyapunov functionalsdesign techniqueNonlinear systemlcsh:TA1-2040data packet dropoutlcsh:Engineering (General). Civil engineering (General)Mathematical Problems in Engineering
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D-Optimal Design for Parameter Estimation in Discrete-Time Nonlinear Dynamic Systems

2012

Published version of an article from the journal: Mathematical Problems in Engineering. Also available from the publisher:http://dx.doi.org/10.1155/2012/296701 An optimal input design method for parameter estimation in a discrete-time nonlinear system is presented in the paper to improve the observability and identification precision of model parameters. Determinant of the information matrix is used as the criterion function which is generally a nonconvex function about the input signals to be designed. To avoid the locally optimizing problem, a randomized designmethod is proposed bywhich a globally optimizing test plan other than input signals may be obtained. Then the randomized design ca…

VDP::Mathematics and natural science: 400::Mathematics: 410::Applied mathematics: 413Optimal designMathematical optimizationArticle SubjectComputer scienceEstimation theoryIterative methodlcsh:MathematicsGeneral MathematicsGeneral EngineeringFunction (mathematics)lcsh:QA1-939Dynamic programmingNonlinear systemDiscrete time and continuous timelcsh:TA1-2040Control theoryObservabilitylcsh:Engineering (General). Civil engineering (General)Mathematical Problems in Engineering
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A novel identification method for generalized T-S fuzzy systems

2012

Published version of an article from the journal: Mathematical Problems in Engineering. Also available from the publisher:http://dx.doi.org/10.1155/2012/893807 In order to approximate any nonlinear system, not just affine nonlinear systems, generalized T-S fuzzy systems, where the control variables and the state variables, are all premise variables are introduced in the paper. Firstly, fuzzy spaces and rules were determined by using ant colony algorithm. Secondly, the state-space model parameters are identified by using genetic algorithm. The simulation results show the effectiveness of the proposed algorithm

VDP::Mathematics and natural science: 400::Mathematics: 410::Applied mathematics: 413State variableMathematical optimizationArticle SubjectGeneral MathematicsAnt colony optimization algorithmsPopulation-based incremental learninglcsh:MathematicsVDP::Technology: 500General EngineeringFuzzy control systemlcsh:QA1-939Fuzzy logicNonlinear systemlcsh:TA1-2040Fuzzy set operationslcsh:Engineering (General). Civil engineering (General)AlgorithmMathematicsFSA-Red Algorithm
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