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Motion on lie groups and its applications in control theory

Cariñena, José F.; Clemente-Gallardo, Jesús; Ramos, Arturo
Fonte: Universidade de Coimbra Publicador: Universidade de Coimbra
Tipo: Artigo de Revista Científica Formato: aplication/PDF
ENG
Relevância na Pesquisa
55.67%
The usefulness in control theory of the geometric theory of motion on Lie groups and homogeneous spaces will be shown. We quickly review some recent results concerning two methods to deal with these systems, namely, a generalization of the method proposed by Wei and Norman for linear systems, and a reduction procedure. This last method allows us to reduce the equation on a Lie group G to that on a subgroup H, provided a particular solution of an associated problem in G/H is known. These methods are shown to be very appropriate to deal with control systems on Lie groups and homogeneous spaces, through the specific examples of the planar rigid body with two oscillators and the front-wheel driven kinematic car.; http://www.sciencedirect.com/science/article/B6VN0-49F836Y-3/1/3e135eb33cca05a026b85455b5544308

Fenômeno Fuller em problemas de controle ótimo: trajetórias em tempo mínino de veículos autônomos subaquáticos; Fuller Phenomenon in optimal control problems: minimum time path of autonomous underwater vehicles.

Oda, Eduardo
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 03/06/2008 PT
Relevância na Pesquisa
55.71%
As equações do modelo bidimensional de veículos autônomos subaquáticos fornecem um exemplo de sistema de controle não linear com o qual podemos ilustrar propriedades da teoria de controle ótimo. Apresentamos, sistematicamente, como os conceitos de formalismo hamiltoniano e teoria de Lie aparecem de forma natural neste contexto. Para tanto, estudamos brevemente o Princípio do Máximo de Pontryagin e discutimos características de sistemas afins. Tratamos com cuidado do Fenômeno Fuller, fornecendo critérios para decidir quando ele está ou não presente em junções, utilizando para isso uma linguagem algébrica. Apresentamos uma abordagem numérica para tratar problemas de controle ótimo e finalizamos com a aplicação dos resultados ao modelo bidimensional de veículo autônomo subaquático.; The equations of the two-dimensional model for autonomous underwater vehicles provide an example of a nonlinear control system which illustrates properties of optimal control theory. We present, systematically, how the concepts of the Hamiltonian formalism and the Lie theory naturally appear in this context. For this purpose, we briefly study the Pontryagin's Maximum Principle and discuss features of affine systems. We treat carefully the Fuller Phenomenon...

Análise da dinâmica e da prática do planejamento e controle da produção: uma abordagem combinada de estudo de caso e modelagem de sistemas dinâmicos; Analysis of the dynamics and practice of the production planning and control: an approach combining case study and system dynamics modeling

Sagawa, Juliana Keiko
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Tese de Doutorado Formato: application/pdf
Publicado em 01/10/2013 PT
Relevância na Pesquisa
55.67%
Os paradigmas de mercado e produção têm-se alterado sensivelmente nos últimos cinquenta anos. Nesse novo contexto, para que as empresas tenham um desempenho competitivo, deve-se considerar fatores como integração, qualidade da informação e incertezas do ambiente. Um dos objetivos principais deste trabalho é analisar as inter-relações entre esses três fatores citados, no âmbito do Planejamento e Controle da Produção (PCP), bem como avaliar seu impacto no desempenho do PCP e da empresa. O desempenho do PCP foi avaliado considerando-se o nível de reprogramações, ou seja, o nível de modificações na programação da produção, e considerando-se o atendimento das metas definidas para os indicadores dessa função. Essa pesquisa qualitativa e descritiva foi feito por meio da metodologia de estudo de casos múltiplos. Como resultados, foram observadas evidências da existência de relações positivas entre os constructos analisados, ou seja, integração, incerteza, qualidade da informação e desempenho. Além disso, foram identificados diferentes mecanismos de integração utilizados nas empresas, e foram observadas diferentes causas para as reprogramações. O segundo objetivo principal deste trabalho é o desenvolvimento de um modelo dinâmico para controle da produção de múltiplos produtos...

Optimal linear and nonlinear control design for chaotic systems

Rafikov, Marat; Balthazar, José Manoel
Fonte: Universidade Estadual Paulista Publicador: Universidade Estadual Paulista
Tipo: Conferência ou Objeto de Conferência Formato: 867-873
ENG
Relevância na Pesquisa
55.73%
In this work, the linear and nonlinear feedback control techniques for chaotic systems were been considered. The optimal nonlinear control design problem has been resolved by using Dynamic Programming that reduced this problem to a solution of the Hamilton-Jacobi-Bellman equation. In present work the linear feedback control problem has been reformulated under optimal control theory viewpoint. The formulated Theorem expresses explicitly the form of minimized functional and gives the sufficient conditions that allow using the linear feedback control for nonlinear system. The numerical simulations for the Rössler system and the Duffing oscillator are provided to show the effectiveness of this method. Copyright © 2005 by ASME.

A proposed neural control for the trajectory tracking of a nonholonomic mobile robot with disturbances

Martins, Nardênio A.; De Alencar, Maycol; Lombardi, Warody C.; Bertol, Douglas W.; De Pieri, Edson R.; Filho, Humberto F.
Fonte: Universidade Estadual Paulista Publicador: Universidade Estadual Paulista
Tipo: Conferência ou Objeto de Conferência Formato: 330-338
ENG
Relevância na Pesquisa
55.73%
In this paper, a trajectory tracking control problem for a nonholonomic mobile robot by the integration of a kinematic neural controller (KNC) and a torque neural controller (TNC) is proposed, where both the kinematic and dynamic models contains disturbances. The KNC is a variable structure controller (VSC) based on the sliding mode control theory (SMC), and applied to compensate the kinematic disturbances. The TNC is a inertia-based controller constituted of a dynamic neural controller (DNC) and a robust neural compensator (RNC), and applied to compensate the mobile robot dynamics, and bounded unknown disturbances. Stability analysis with basis on Lyapunov method and simulations results are provided to show the effectiveness of the proposed approach. © 2012 Springer-Verlag.

Gerenciamento ativo de filas para o protocolo "High Speed Transmission Control Protocol" em redes com produto banda-atraso elevado; Active queue management High Speed Transmission Control Protocol in high bandwidth-delay networks

Juliana de Santi
Fonte: Biblioteca Digital da Unicamp Publicador: Biblioteca Digital da Unicamp
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 26/06/2008 PT
Relevância na Pesquisa
55.69%
A utilização eficiente da banda passante em redes de alta velocidade e grandes atrasos, denominadas redes com produto banda-atraso elevado (PBA), tornou-se um grande desafio. Isto ocorre devido aos ajustes do protocolo Transmission Control Protocol (TCP). O High Speed TCP (HSTCP), uma variante do TCP para redes com PBA elevado, emprega ajustes mais agressivos permitindo, assim, que a utilização da banda seja escalável. As políticas de Gerenciamento Ativo de Filas ou Active Queue Management (AQM), monitoram o nível de ocupação das filas nos roteadores e notificam o congestionamento incipiente aos emissores TCP através do descarte/marcação de pacotes. O sistema de controle de congestionamento apresenta natureza de retroalimentação, na qual a taxa de transmissão dos nós fontes é ajustada em função do nível de ocupação da fila. Os controladores AQM determinam a probabilidade de descarte/marcação para maximizar a vazão e minimizar perdas, garantindo, assim, a estabilidade do tamanho da fila independentemente das variações das condições da rede. Neste trabalho, define-se a política de gerenciamento ativo de filas HSTCP-H2 para redes com PBA elevado que utilizam o protocolo HSTCP. Para a derivação de HSTCP­H2: são utilizadas técnicas de Teoria de Controle Ótimo. A principal característica desta política é considerar o atraso do sistema o que permite melhor utilização dos recursos disponíveis. A estabilidade e os objetivos de desempenho do sistema são expressos e solu­cionados através de Desigualdades Matriciais Lineares...

Técnicas não lineares de controle e filtragem aplicadas ao problema de rastreamento de trajetórias de robôs móveis com deslizamento longitudinal das rodas; Nonlinear techniques of control and filtering applied to the trajectory tracking problem of mobile robots with longitudinal wheel slip

Juliano Gonçalves Iossaqui
Fonte: Biblioteca Digital da Unicamp Publicador: Biblioteca Digital da Unicamp
Formato: application/pdf
Publicado em 28/02/2013 PT
Relevância na Pesquisa
55.77%
Esta tese trata do problema de controle de trajetórias de robôs móveis não holonômicos com deslizamento longitudinal das rodas. As estratégias de controle propostas são projetadas usando dois modelos, um cinemático e um dinâmico, que consideram os deslizamentos longitudinais das rodas como parâmetros desconhecidos. A primeira estratégia de controle consiste em um controlador adaptativo projetado com base em um modelo cinemático que utiliza como entrada de controle, as velocidades angulares das rodas. Essas velocidades angulares são fornecidas por uma lei de controle cinemática que utiliza estimativa dos parâmetros de deslizamento desconhecidos, obtidas por meio de uma lei de adaptação. A segunda estratégia de controle consiste em um controlador adaptativo projetado com base em um modelo dinâmico simplificado que utilizam como entrada de controle, forças de propulsão aplicadas no centro das rodas. A lei de controle, que fornece essas forças, é projetada aplicando-se a técnica backstepping ao modelo dinâmico reduzido, que foi obtido com a utilização do método da dinâmica inversa. Os parâmetros de deslizamento longitudinal desconhecidos, necessários para a utilização do método da dinâmica inversa, são estimados por uma lei de adaptação. O filtro de Kalman unscented também é utilizado para estimar os parâmetros de deslizamento desconhecidos. Essas estimativas são utilizadas...

Optimal control for a tuberculosis model with reinfection and post-exposure interventions

Silva, C. J.; Torres, D. F. M.
Fonte: Elsevier Publicador: Elsevier
Tipo: Artigo de Revista Científica
ENG
Relevância na Pesquisa
55.75%
We apply optimal control theory to a tuberculosis model given by a system of ordinary differential equations. Optimal control strategies are proposed to minimize the cost of interventions, considering reinfection and post-exposure interventions. They depend on the parameters of the model and reduce effectively the number of active infectious and persistent latent individuals. The time that the optimal controls are at the upper bound increase with the transmission coefficient. A general explicit expression for the basic reproduction number is obtained and its sensitivity with respect to the model parameters is discussed. Numerical results show the usefulness of the optimization strategies. © 2013 Elsevier Inc.

Software maintenance through supervisory control

Gaudin, Benoit; Bagnato, Alessandra
Fonte: IEEE Computer Society Publicador: IEEE Computer Society
Tipo: Conference item; all_ul_research; none
ENG
Relevância na Pesquisa
55.73%
peer-reviewed; This work considers the case of system maintenance where systems are already deployed and for which some faults or security issues were not detected during the testing phase. We propose an approach based on control theory that allows for automatic generation of maintenance fixes. This approach disables faulty or vulnerable system functionalities and requires to instrument the system before deployment so that it can later be monitored and interact with a supervisor at runtime. This supervisor ensures some property designed after deployment in order to avoid future executions of faulty or vulnerable system functionalities. This property corresponds to a set of safe behaviors described as a Finite State Machine. The computation of supervisors can be performed automatically, relying on a sound Supervisory Control Theory. We first introduce some basic notions of Supervisory Control theory, then we present and illustrate our approach which also relies on automatic models extraction and instrumentation.

A Keynesian critique of recent finance and macroeconomic applications of risk-sensitive and robust control theory / James Juniper.

Juniper, James
Fonte: Universidade de Adelaide Publicador: Universidade de Adelaide
Tipo: Tese de Doutorado Formato: 108298 bytes; application/pdf
Publicado em //2001 EN
Relevância na Pesquisa
65.65%
The objective of this thesis is to assess the strengths and weaknesses of recent economic applications of robust and risk-sensitive control theory from a Keynesian perspective.; Thesis (Ph.D.)--University of Adelaide, Dept. of Economics, 2001?; Bibliography: leaves 479-544.; v, 544 leaves : ill. ; 30 cm.; Title page, contents and abstract only. The complete thesis in print form is available from the University Library.

A control theory based approach for self-healing of un-handled runtime exceptions

Gaudin, Benoit; Vassev, Emil; Hinchey, Mike; Nixon, Paddy
Fonte: Association for Computing Machinery Publicador: Association for Computing Machinery
Tipo: Conference item; all_ul_research; ul_published_reviewed; none
ENG
Relevância na Pesquisa
65.72%
non-peer-reviewed; This work presents an approach to self-healing that deals with un-handled exceptions within an executing program. More precisely, we propose an approach based on control theory that automatically disables system functionalities that have led to runtime exceptions. This approach requires the system to be instrumented prior to deployment so that it can later interact with a supervisor. This supervisor en- codes the only sequences of actions (method calls) of the system that are permitted. We describe an implementation that automatically generates instrumentation for Java systems. We introduce an extension of Supervisory Control theory that enables automatic computation of a supervisor/controller model ensuring that an observed trace leading to an un-handled runtime exception cannot occur anymore. We demonstrate the e cacy of this approach through a comprehensive example.

Applications of Lie systems in Quantum Mechanics and Control Theory

Cariñena, José F.; Ramos, Arturo
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 09/05/2003
Relevância na Pesquisa
55.73%
Some simple examples from quantum physics and control theory are used to illustrate the application of the theory of Lie systems. We will show, in particular, that for certain physical models both of the corresponding classical and quantum problems can be treated in a similar way, may be up to the replacement of the involved Lie group by a central extension of it. The geometric techniques developed for dealing with Lie systems are also used in problems of control theory. Specifically, we will study some examples of control systems on Lie groups and homogeneous spaces.; Comment: LaTeX, 28 pages

Uniformly hyperbolic control theory

Kawan, Christoph
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 25/11/2015
Relevância na Pesquisa
55.76%
This paper gives a summary of a body of work at the intersection of control theory and smooth nonlinear dynamics. The main idea is to transfer the concept of uniform hyperbolicity, central to the theory of smooth dynamical systems, to control-affine systems. Combining the strength of geometric control theory and the hyperbolic theory of dynamical systems, it is possible to deduce control-theoretic results of non-local nature that reveal remarkable analogies to the classical hyperbolic theory of dynamical systems.

Mathematical models for geometric control theory

Jafarpour, Saber; Lewis, Andrew D.
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Relevância na Pesquisa
55.75%
Just as an explicit parameterisation of system dynamics by state, i.e., a choice of coordinates, can impede the identification of general structure, so it is too with an explicit parameterisation of system dynamics by control. However, such explicit and fixed parameterisation by control is commonplace in control theory, leading to definitions, methodologies, and results that depend in unexpected ways on control parameterisation. In this paper a framework is presented for modelling systems in geometric control theory in a manner that does not make any choice of parameterisation by control; the systems are called "tautological control systems." For the framework to be coherent, it relies in a fundamental way on topologies for spaces of vector fields. As such, classes of systems are considered possessing a variety of degrees of regularity: finitely differentiable; Lipschitz; smooth; real analytic. In each case, explicit geometric seminorms are provided for the topologies of spaces of vector fields that enable straightforward descriptions of time-varying vector fields and control systems. As part of the development, theorems are proved for regular (including real analytic) dependence on initial conditions of flows of vector fields depending measurably on time. Classes of "ordinary" control systems are characterised that interact with the regularity under consideration in a comprehensive way. In this framework...

Descriptive Control Theory: A Proposal

Gao, Sicun
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Relevância na Pesquisa
55.74%
Logic is playing an increasingly important role in the engineering of real-time, hybrid, and cyber-physical systems, but mostly in the form of posterior verification and high-level analysis. The core methodology in the design of real-world systems consists mainly of control theory and numerical analysis, and has remained mostly free of logic and formal approaches. As a result, besides facing extreme difficulty in guaranteeing the reliability of these systems, engineers are also missing out the computational power of logic-based methods that has greatly advanced in the past decades. To change this situation, we need a logical and computational foundation for control theory. The name "descriptive control theory" emphasizes the overarching theme of using logic to express, analyze, and solve problems in control theory. If the program is successfully carried out, logical approaches will significantly extend existing engineering methods towards a unified methodology for handling nonlinear and hybrid systems, and bring design automation and reliability to an unprecedented level in the broad field of engineering.

Uncertainty Principle in Control Theory, Part I: Analysis of Performance Limitations

King, Ji
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 21/02/2014
Relevância na Pesquisa
55.69%
This paper investigates performance limitations and tradeoffs in the control design for linear time-invariant systems. It is shown that control specifications in time domain and in frequency domain are always mutually exclusive determined by uncertainty relations. The uncertainty principle from quantum mechanics and harmonic analysis therefore embeds itself inherently in control theory. The relations among transient specifications, system bandwidth and control energy are obtained within the framework of uncertainty principle. If the control system is provided with a large bandwidth or great control energy, then it can ensure transient specifications as good as it can be. Such a control system could be approximated by prolate spheroidal wave functions. The obtained results are also applicable to filter design due to the duality of filtering and control.; Comment: 20 pages, 6 figures

Quantum control theory and applications: A survey

Dong, Daoyi; Petersen, Ian R
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Relevância na Pesquisa
55.75%
This paper presents a survey on quantum control theory and applications from a control systems perspective. Some of the basic concepts and main developments (including open-loop control and closed-loop control) in quantum control theory are reviewed. In the area of open-loop quantum control, the paper surveys the notion of controllability for quantum systems and presents several control design strategies including optimal control, Lyapunov-based methodologies, variable structure control and quantum incoherent control. In the area of closed-loop quantum control, the paper reviews closed-loop learning control and several important issues related to quantum feedback control including quantum filtering, feedback stabilization, LQG control and robust quantum control.; Comment: 38 pages, invited survey paper from a control systems perspective, some references are added, published version

Asymptotic control theory for a system of linear oscillators

Fedorov, Aleksey; Ovseevich, Alexander
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Relevância na Pesquisa
55.72%
We present asymptotical control theory for a system of an arbitrary number of linear oscillators under common bounded control. We suggest a method for a design of a feedback control for the system. We prove by using the DiPerna-Lions theory of singular ODE that the suggested control law correctly defines a motion of the system. The obtained control is asymptotically optimal: the ratio of motion time to zero with this control to the minimum one is close to 1, if the initial energy of the system is large. Some of the results are based on a new lemma about observability of perturbed autonomous linear systems.; Comment: 32 pages; v. 2: substantially revised

Control of Vibratory Energy Harvesters in the Presence of Nonlinearities and Power-Flow Constraints

Cassidy, Ian Lerner
Fonte: Universidade Duke Publicador: Universidade Duke
Tipo: Dissertação
Publicado em //2012
Relevância na Pesquisa
55.7%

Over the past decade, a significant amount of research activity has been devoted to developing electromechanical systems that can convert ambient mechanical vibrations into usable electric power. Such systems, referred to as vibratory energy harvesters, have a number of useful of applications, ranging in scale from self-powered wireless sensors for structural health monitoring in bridges and buildings to energy harvesting from ocean waves. One of the most challenging aspects of this technology concerns the efficient extraction and transmission of power from transducer to storage. Maximizing the rate of power extraction from vibratory energy harvesters is further complicated by the stochastic nature of the disturbance. The primary purpose of this dissertation is to develop feedback control algorithms which optimize the average power generated from stochastically-excited vibratory energy harvesters.

This dissertation will illustrate the performance of various controllers using two vibratory energy harvesting systems: an electromagnetic transducer embedded within a flexible structure, and a piezoelectric bimorph cantilever beam. Compared with piezoelectric systems, large-scale electromagnetic systems have received much less attention in the literature despite their ability to generate power at the watt--kilowatt scale. Motivated by this observation...

Optimal economic planning and control for the management of ecosystems

Macksamie, Kevin
Fonte: Rochester Instituto de Tecnologia Publicador: Rochester Instituto de Tecnologia
Tipo: Tese de Doutorado
EN_US
Relevância na Pesquisa
55.73%
In recent years the interest on sustainable systems has increased significantly. Among the many interested problems, creating and restoring sustainable ecosystems is a challenging and complex problem. One of the fundamental problems within this area is the imbalance between species that have a predator-prey relationship. Solutions involving management have become an integral player in many environments. Management systems typically use ad hoc methods to develop harvesting policies to control the populations of species to desired numbers. In order to amalgamate intelligence and structure, ecological systems require a diverse research effort from three primary fields: ecology, economics, and control theory. In this thesis, all three primary fields aforementioned are researched to develop a theoretical framework that includes an optimal trajectory planning system that exploits an ecosystem to maximize profits for the supporting community, and a robust control system design to track the optimal trajectories subjected to exogenous disturbances. Population ecology is used to select a model that identifies the key characteristics a management system needs to understand the behavior of the natural environment. A bioeconomic model is developed to relate the species populations to revenue. The nonlinear ecosystem is transformed into a linear parameter-varying (LPV) system that is then controlled using hinf synthesis and the gain scheduling methodology. The consequences of the results in this thesis are that optimal trajectories of an ecosystem can be obtained by constructing and solving a nonlinear programming problem (NLP)...