Search results for "Linear"

showing 10 items of 7165 documents

A microplane model for plane-stress masonry structures

2003

Publisher Summary For a refined nonlinear finite element analysis of masonry structures, an accurate constitutive model that is able to reproduce the desired phenomenological material features is required. Constitutive models for quasi-brittle materials, as plain concrete, have been proposed in the chapter, which allow to reproduce the very complex response in the two- or three-dimensional state of stress. Usually, the constitutive relations proposed are based on some appropriate extensions of elastic-plastic continuum models and more recently on continuum damage models. It has been observed that for these tensorial-based constitutive relations to be effective often require a large number o…

EngineeringNonlinear FEContinuum (measurement)business.industryConstitutive equationStructural engineeringMasonry structuresMasonrybusinessNonlinear finite element analysisMicroplane modelSettore ICAR/08 - Scienza Delle CostruzioniPlane stress
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NARX Models of an Industrial Power Plant Gas Turbine

2005

This brief reports the experience with the identification of a nonlinear autoregressive with exogenous inputs (NARX) model for the PGT10B1 power plant gas turbine manufactured by General Electric-Nuovo Pignone. Two operating conditions of the turbine are considered: isolated mode and nonisolated mode. The NARX model parameters are estimated iteratively with a Gram-Schmidt procedure, exploiting both forward and stepwise regression. Many indexes have been evaluated and compared in order to perform subset selection in the functional basis set and determine the structure of the nonlinear model. Various input signals (from narrow to broadband) for identification and validation have been consider…

EngineeringNonlinear autoregressive exogenous modelbusiness.industryTurbinesSystem identificationControl engineeringNonlinear controlTurbineDistributed power generationElectric power systemNonlinear systemAutoregressive modelControl and Systems EngineeringSteam turbineControl theoryElectrical and Electronic EngineeringbusinessGas turbines
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Robust adaptive backstepping control design for a Nonlinear Hydraulic-Mechanical System

2009

The complex dynamics that characterize hydraulic systems make it difficult for the control design to achieve prescribed goals in an efficient manner. In this paper, we present the design and analysis of a robust nonlinear controller for a Nonlinear Hydraulic-Mechanical (NHM) System. The system consists of an electrohydraulic servo valve and two hydraulic cylinders. Specifically, by considering a part of the dynamics of the NHM system as a norm-bounded uncertainty, two adaptive controllers are developed based on the backstepping technique that ensure the tracking error signals asymptotically converge to zero despite the uncertainties in the system according to the Barbalat lemma. The resulti…

EngineeringNonlinear systemHydraulic cylinderAdaptive controlbusiness.industryControl theoryRobustness (computer science)BacksteppingControl engineeringRobust controlHydraulic machinerybusinessElectrohydraulic servo valveProceedings of the 48h IEEE Conference on Decision and Control (CDC) held jointly with 2009 28th Chinese Control Conference
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An Object-Oriented Approach to Discrete-Event Simulation Applied to Underground Railway Systems

1999

This paper describes the implementation of an object-oriented simulator that supports the determination of timetables and the design of on-line control policies for underground rail way systems. The simulator has been developed on the basis of a new approach to object- oriented modelling. Such an approach has been used to design a development tool that supports the generation of simulation codes and is able to automatically define the skeleton of a code.

EngineeringObject-oriented programming021103 operations researchDiscrete event systemBasis (linear algebra)business.industryDistributed computing0211 other engineering and technologies02 engineering and technologyObject (computer science)Computer Graphics and Computer-Aided DesignModeling and SimulationObject oriented simulationRail transportation0202 electrical engineering electronic engineering information engineeringUrban transportation020201 artificial intelligence & image processingDiscrete event simulationbusinessSoftwareSimulationSIMULATION
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MRAS speed observer for high performance linear induction motor drives based on linear neural networks

2011

This paper proposes a Neural Network (NN) MRAS (Model Reference Adaptive System) speed observer suited for linear induction motor (LIM) drives. The voltage and current models of the LIM in the stationary reference frame, taking into consideration the end effects, have been obtained. Then, equations of the induced part have been discretized and rearranged so as to be represented by a linear neural network the TLS EXIN neuron, which has been used to compute the machine linear speed on-line and in recursive form. The proposed NN MRAS observer has been tested experimentally on a suitably developed test setup. Its performance has been also compared to the classic MRAS speed observer.

EngineeringObserver (quantum physics)Artificial neural networkDiscretizationControl theorybusiness.industryAdaptive systemLinear induction motorbusinessMRASStationary Reference FrameMachine control2011 IEEE Energy Conversion Congress and Exposition
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Robust output feedback ℌ<inf>∞</inf> control synthesis with pole placement for offshore wind turbine system: An LMI…

2012

This paper deals with output ℌ ∞ control synthesis for a linear parameter-varying model of a floating wind turbine. A nonlinear model is introduced and linearized to obtain a linear model for each desired azimuth angle using the wind turbine software FAST. The main contributions of this paper are threefold. Firstly, the family of linear models are represented based on an affine parameter-varying model structure. Secondly, the bounded parameter-varying parameters are removed using upper bounded inequalities in the control design process. Thirdly, the control problem is formulated in terms of linear matrix inequalities (LMIs). The simulation results show a comparison between a controller desi…

EngineeringOffshore wind powerMathematical optimizationbusiness.industryControl theoryLinear systemFull state feedbackLinear modelFloating wind turbineRobust controlbusinessTurbine2012 IEEE International Conference on Control Applications
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Linear vs. non-linear classification of winners, drawers and losers at FIFA World Cup 2014

2017

Purpose: Tactical analyses to distinguish between football teams that were more or less successful have been conducted up to now only by means of linear methods (like discriminant analysis). Concer...

EngineeringOperations researchbusiness.industry030209 endocrinology & metabolismPhysical Therapy Sports Therapy and Rehabilitation030229 sport sciencesFootballLinear discriminant analysisMachine learningcomputer.software_genreLinear methods03 medical and health sciencesNonlinear system0302 clinical medicineTourism Leisure and Hospitality ManagementNotational analysisOrthopedics and Sports MedicineArtificial intelligencebusinesscomputerScience and Medicine in Football
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Feasibility issues in static output-feedback controller design with application to structural vibration control

2014

Recent results in output-feedback controller design make possible an efficient computation of static output-feedback controllers by solving a single-step LMI optimization problem. This new design strategy is based on a simple transformation of variables, and it has been applied in the field of vibration control of large structures with positive results. There are, however, some feasibility problems that can compromise the effectiveness and applicability of the new approach. In this paper, we present some relevant properties of the variable transformations that allow devising an effective procedure to deal with these feasibility issues. The proposed procedure is applied in designing a static…

EngineeringOptimization problem:Informàtica::Automàtica i control [Àrees temàtiques de la UPC]Computer Networks and CommunicationsComputationVibration controlDesign strategyFeedback control systemsMatrius (Matemàtica)Field (computer science)Control theorymatrix theoryMatrix inequalitiesbusiness.industryApplied Mathematics:15 Linear and multilinear algebra; matrix theory [Classificació AMS]:15 Linear and multilinear algebra [Classificació AMS]:Matemàtiques i estadística [Àrees temàtiques de la UPC]Control engineeringVariable (computer science)Transformation (function)Control and Systems EngineeringSistemes de control per retroaccióSignal ProcessingControl and Systems Engineering; Computer Networks and Communications; Applied Mathematics; Signal ProcessingbusinessJournal of the Franklin Institute
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Vibration control for adjacent structures using local state information

2014

In this paper, a novel strategy for structural vibration control of multi-structure systems is presented. This strategy pays particular attention to mitigating negative interstructure interactions. Moreover, it is based on recent advances in static output–feedback control, which make possible the efficient computation of decentralized velocity-feedback controllers by solving a single-step optimization problem with Linear Matrix Inequality constraints. To illustrate the main ideas, a local velocity-feedback energy-to-peak controller is designed for the seismic protection of a two-building system. This controller is remarkably effective and extremely simple. Moreover, it can also be implement…

EngineeringOptimization problem:Informàtica::Automàtica i control [Àrees temàtiques de la UPC]Static output-feedbackComputationControl (management)Vibration controlEdificis -- Vibració:Enginyeria civil::Materials i estructures [Àrees temàtiques de la UPC]Feedback control systemsDamperStructural vibration controlControl d'estructures (Enginyeria)Control theorySimple (abstract algebra)Buildings -- VibrationElectrical and Electronic EngineeringMulti-structure systemsbusiness.industryMechanical EngineeringLinear matrix inequalityPassive damping designComputer Science Applications1707 Computer Vision and Pattern RecognitionControl engineeringComputer Science ApplicationsMulti-structure systems; Passive damping design; Static output-feedback; Structural vibration control; Mechanical Engineering; Electrical and Electronic Engineering; Computer Science Applications1707 Computer Vision and Pattern RecognitionControl and Systems EngineeringSistemes de control per retroaccióBuildings--VibrationStructural control (Engineering)business
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Passive-damping design for vibration control of large structures

2013

In this work, a systematic strategy to design passive damping systems for structural vibration control is presented. The proposed design methodology is based on the equivalence between decentralized static velocity-feedback controllers and passive damping systems. By using recent developments in static output-feedback control, the design of passivedamping systems can be formulated as a single optimization problem with Linear Matrix Inequality constraints. Moreover, this optimization problem can be efficiently solved with standard numerical tools, even for large dimension systems. Due to its computational effectiveness, the proposed methodology can be applied to the design of passive damping…

EngineeringOptimization problem:Informàtica::Automàtica i control [Àrees temàtiques de la UPC]business.industryWork (physics)Vibration controlLinear matrix inequalityEdificis -- VibracióControl engineering:Enginyeria civil::Materials i estructures [Àrees temàtiques de la UPC]Feedback control systemsControl d'estructures (Enginyeria)Dimension (vector space)Control theorySistemes de control per retroaccióBuildings--VibrationSeismic protectionStructural control (Engineering)Buildings -- VibrationbusinessDesign methodsEquivalence (measure theory)
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