Estudo comparativo do desempenho de controladores robustos aplicados a um sistema de tanques acoplados.

Currently the uncertain system has attracted much academic community from the standpoint of scientific research and also practical applications. A series of mathematical approaches emerge in order to troubleshoot the uncertainties of real physical systems. In this context, the work presented here focuses on the application of control theory in a nonlinear dynamical system with parametric variations in order and robustness. We used as the practical application of this work, a system of tanks Quanser associates, in a configuration, whose mathematical model is represented by a second order system with input and output (SISO). The control system is performed by PID controllers, designed by various techniques, aiming to achieve robust performance and stability when subjected to parameter variations. Other controllers are designed with the intention of comparing the performance and robust stability of such systems. The results are obtained and compared from simulations in Matlab-simulink.

Identificação de uma planta de corrente de um motor de indução utilizando redes de base radial

The present work describes the use of a mathematical tool to solve problems arising from control theory, including the identification, analysis of the phase portrait and stability, as well as the temporal evolution of the plant s current induction motor. The system identification is an area of mathematical modeling that has as its objective the study of techniques which can determine a dynamic model in representing a real system. The tool used in the identification and analysis of nonlinear dynamical system is the Radial Basis Function (RBF). The process or plant that is used has a mathematical model unknown, but belongs to a particular class that contains an internal dynamics that can be modeled.Will be presented as contributions to the analysis of asymptotic stability of the RBF. The identification using radial basis function is demonstrated through computer simulations from a real data set obtained from the plant

Planejamento cooperativo de tarefas em um ambiente de futebol de robôs

Este trabalho apresenta o desenvolvimento de um método de coordenação e cooperação para uma frota de mini-robôs móveis. O escopo do desenvolvimento é o futebol de robôs. Trata-se de uma plataforma bem estruturada, dinâmica e desenvolvida no mundo inteiro. O futebol de robôs envolve diversos campos do conhecimento incluindo: visão computacional, teoria de controle, desenvolvimento de circuitos microcontrolados, planejamento cooperativo, entre outros. A título de organização os sistema foi dividido em cinco módulos: robô, visão, localização, planejamento e controle. O foco do trabalho se limita ao módulo de planejamento. Para auxiliar seu desenvolvimento um simulador do sistema foi implementado. O simulador funciona em tempo real e substitui os robôs reais. Dessa forma os outros módulos permanecem praticamente inalterados durante uma simulação ou execução com robôs reais. Para organizar o comportamento dos robôs e produzir a cooperação entre eles foi adotada uma arquitetura hierarquizada: no mais alto nível está a escolha do estilo de jogo do time; logo abaixo decide-se o papel que cada jogador deve assumir; associado ao papel temos uma ação específica e finalmente calcula-se a referência de movimento do robô. O papel de um robô dita o comportamento do robô na dada ocasião. Os papéis são alocados dinamicamente durante o jogo de forma que um mesmo robô pode assumir diferentes papéis no decorrer da partida

Métodos numéricos para resolução de equações diferenciais ordinárias lineares baseados em interpolação por spline

In this work we have elaborated a spline-based method of solution of inicial value problems involving ordinary differential equations, with emphasis on linear equations. The method can be seen as an alternative for the traditional solvers such as Runge-Kutta, and avoids root calculations in the linear time invariant case. The method is then applied on a central problem of control theory, namely, the step response problem for linear EDOs with possibly varying coefficients, where root calculations do not apply. We have implemented an efficient algorithm which uses exclusively matrix-vector operations. The working interval (till the settling time) was determined through a calculation of the least stable mode using a modified power method. Several variants of the method have been compared by simulation. For general linear problems with fine grid, the proposed method compares favorably with the Euler method. In the time invariant case, where the alternative is root calculation, we have indications that the proposed method is competitive for equations of sifficiently high order.

O consumo de álcool entre os adolescentes estudantes de escolar privadas católicas de Natal-RN

This study has an object the understanding of the alcohol phenomenon consumption that occurs among teenagers. It is adopted as research locus catholic private schools of Natal - RN, which receive pupils proceeding from the social groups pertaining to the classes taken from Natal private schools. The researched public corresponds to 87 teenagers, who had answered to a mixing questionnaire, with open and closed questions. The research uses as a procedure the intentional election, which for the access easinesses privileges subjects who, at the moment of the research accomplishment, reveal to be in condition to participate of it. The study presents quantitative and qualitative character. It presents the following objectives: 1-Identify in which circumstances the teenagers make alcoholic beverage use; 2 -To identify the knowledge that the teenagers have on the alcohol effects; 3 -To identify the performance role of the school institution on the prevention of alcohol use by teenagers. The analysis method used corresponds to the one called answers interpretation method. Regards to the theoretical-methodological support, the Social Control Theory and the Symbolic Interactionism Theory are adopted as referential. Its contained chapters are organized in the following way: The first chapter approaches the situation of drugs adolescent consumption in general and the social confrontation of this situation. The second chapter presents sociocultural aspects of the alcohol consumption and the description of some of the researched public characteristics. The third chapter emphasizes the school and its performance next to the teenagers and the society in general, towards the prevention and combat of the alcohol use, as well as of other drugs

Um controlador dual subótimo com fator de peso variável no tempo

This work concerns a refinement of a suboptimal dual controller for discrete time systems with stochastic parameters. The dual property means that the control signal is chosen so that estimation of the model parameters and regulation of the output signals are optimally balanced. The control signal is computed in such a way so as to minimize the variance of output around a reference value one step further, with the addition of terms in the loss function. The idea is add simple terms depending on the covariance matrix of the parameter estimates two steps ahead. An algorithm is used for the adaptive adjustment of the adjustable parameter lambda, for each step of the way. The actual performance of the proposed controller is evaluated through a Monte Carlo simulations method.

Estudo comparativo do desempenho de controladores robustos aplicados a um sistema de tanques acoplados.

Currently the uncertain system has attracted much academic community from the standpoint of scientific research and also practical applications. A series of mathematical approaches emerge in order to troubleshoot the uncertainties of real physical systems. In this context, the work presented here focuses on the application of control theory in a nonlinear dynamical system with parametric variations in order and robustness. We used as the practical application of this work, a system of tanks Quanser associates, in a configuration, whose mathematical model is represented by a second order system with input and output (SISO). The control system is performed by PID controllers, designed by various techniques, aiming to achieve robust performance and stability when subjected to parameter variations. Other controllers are designed with the intention of comparing the performance and robust stability of such systems. The results are obtained and compared from simulations in Matlab-simulink.

Vigilância eletrônica no trabalho bancário: do controle consentido ao totalitarismo corporativo

This dissertation addresses the electronic surveillance theme in the banking context. The research that originated it, which was held in an organization called for the fiction name Banco Total, started from the following driving question: How do workers at a bank perceive electronic surveillance at their process of work? The research s main objective was to comprehend how workers perceive electronic surveillance at their process of work. The study adopted an interdisciplinary perspective, having Management as the original field, establishing a dialogue with others disciplines, like Philosophy and Sociology. About its methodology, it s a qualitative research that addressed its object in oral (interviews with live history elements) way. . Ten individuals were interviewed. The analytical process utilized the hermeneutical-dialectics technique.. From the analyses (hermeneutics) of the data, the following themes have emerged: (i) Acquiescence ; (ii) Monitoring; (iii) Time and Motion; (iv) Fear; (v) Interdiction; and (vi) Resistance . From the discussion (dialectic) of the results, this work presents three synthetic propositions that culminate in the following dimensions (i) control; (ii) acquiescence; (iii) corporative totalitarianism. It can be concluded that electronic surveillance is one mechanism of control emerged from the apply of technology at Total Bank; that information technology has been improving the control mechanisms of management theories; and that the imbrications between management and material technology control mechanisms at a context where there is acquiescence by workers contribute for the emergency of corporative totalitarianism components

Abordagem psicossociologica das implicações legais da infecção hospitalar e de seu controle

Pesquisas acerca das Infecções Hospitalares mostram a gravidade do problema na saúde e a existência de poucos profissionais das áreas do Direito e da Saúde especializados nas implicações jurídicas relacionadas com o controle das Infecções Hospitalares. Assim, este estudo multidisciplinar tem como objetivos: apreender as Representações Sociais das Implicações Jurídicas das Infecções Hospitalares e de seu Controle, elaboradas pelos profissionais do direito e da saúde e analisar o impacto destas representações sobre Infecções Hospitalares e seu controle no âmbito do Hospital Getúlio Vargas, em Teresina, no Estado do Piauí. Trata-se de um estudo de caráter exploratório, desenvolvido em hospital público com profissionais do Direito e da Saúde, subsidiado na Teoria das Representações Sociais, de Serge Moscovici. Os dados foram coletados através de entrevista em profundidade e da observação. As informações apreendidas foram processadas no software Alceste 4.8, possibilitando a análise lexical e estatística pela Classificação Hierárquica Descendente, que permitiu identificar no discurso classes representativas de palavras de interesse da investigação. Os resultados indicaram que os sujeitos do estudo, através das suas representações sociais, defendem os direitos dos usuários da saúde e conhecem a prática das políticas de saúde, prevenção das Infecções Hospitalares e de seu Controle. Porém, demonstraram pouca preocupação com as implicações jurídicas inerentes às sua práticas mesmo estando sujeitos a responder civil e penalmente pelas ocorrências geradas por iatrogenia no exercício da profissão

Repercussão geral e súmula vinculante: os efeitos no controle difuso

Brazil since its first republican constitution has adopted systems of laws control. The review activity was given to three state powers or functions state, Executive, Legislative and Judiciary. However, it appears that in the country along the constitutional history, has stood considerably the jurisdictional control of the most important control. Initially, back in 1891, Brazil adopted the jurisdictional control of diffuse from U.S, whose role in monitoring of standards is delivered to all organs of the judiciary, which may face a case, put on trial, ascertain whether or not the possibility of applying a law, removing its impact in case of unconstitutionality. In 1969, entered in the second legal model of judicial review, the concentrated control of constitutionality, whose inspiration comes from the positivist theory of Hans Kelsen, and was adopted by the Austrian Constitution of 1920. According to the abstract control the supervision of law is given to a Court or Constitutional Court, responsible for the analysis of the legal constitutionality independent of its application to a specific case. In Brazil the role of concentrated control was handed over exclusively to the Supreme Court, which serves as the Constitutional Court, which accumulates that function with other constitutionally provided jurisdiction. Throughout this period, from 1891 until today, Brazil has maintained a dual system of judicial control of legal constitutionality, where they coexist and harmonize the diffuse control exercised by any organ of the Judiciary, and concentrated control of competence the Supreme Court. However, one must recognize that with the advent of the Federal Constitution of 1988, the concentrated control has emerged on the national stage due to two important factors: the expansion of the legal capacity to sue and the inclusion of other ways control, besides the already known Direct Claim of Unconstitutionality. This concentrated control and projection of the Supreme Court s attempt to become a true constitutional court, led to a relative weakening of diffuse control even when performed by the Brazilian Constitutional Court. In order to become a true constitutional court, all decisions handed down by the Supreme in the exercise of constitutional jurisdiction should have the same weight and the same measure, or at least bring improvement to similar effects, once is the responsible for the final word when it comes to constitutional interpretation. Thus, the writs of certiorari and stare decisis were responsible for profound changes in the diffuse control, allowing the Supreme Court can strengthen its decisions even in the diffuse control. These two institutions have substantially changed the legal status of diffuse control, allowing an extension of the effects of decisions handed down by the Supreme Court, so that you can no longer be said that the effects of this control to restrict the disputing parties in the process

Otimização do controle eletrônico do diagrama de radiação de arranjos de antenas usando algoritmos genéticos com codificação real

Antenna arrays are able to provide high and controlled directivity, which are suitable for radiobase stations, radar systems, and point-to-point or satellite links. The optimization of an array design is usually a hard task because of the non-linear characteristic of multiobjective, requiring the application of numerical techniques, such as genetic algorithms. Therefore, in order to optimize the electronic control of the antenna array radiation pattem through genetic algorithms in real codification, it was developed a numerical tool which is able to positioning the array major lobe, reducing the side lobe levels, canceling interference signals in specific directions of arrival, and improving the antenna radiation performance. This was accomplished by using antenna theory concepts and optimization methods, mainly genetic algorithms ones, allowing to develop a numerical tool with creative genes codification and crossover rules, which is one of the most important contribution of this work. The efficiency of the developed genetic algorithm tool is tested and validated in several antenna and propagation applications. 11 was observed that the numerical results attend the specific requirements, showing the developed tool ability and capacity to handle the considered problems, as well as a great perspective for application in future works.

Utilização da lógica difusa no controle inteligente de sistemas eletro-hidráulicos

Electro-hydraulic servo-systems are widely employed in industrial applications such as robotic manipulators, active suspensions, precision machine tools and aerospace systems. They provide many advantages over electric motors, including high force to weight ratio, fast response time and compact size. However, precise control of electro-hydraulic systems, due to their inherent nonlinear characteristics, cannot be easily obtained with conventional linear controllers. Most flow control valves can also exhibit some hard nonlinearities such as deadzone due to valve spool overlap on the passage´s orifice of the fluid. This work describes the development of a nonlinear controller based on the feedback linearization method and including a fuzzy compensation scheme for an electro-hydraulic actuated system with unknown dead-band. Numerical results are presented in order to demonstrate the control system performance

Controlador adaptativo por modelo de referência e estrutura variável aplicado ao controle de ângulo de carga e fluxo de campo de um gerador síncrono

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior

Controlador adaptativo backstepping a estrutura variavel com Observadores de estado

This research aims at developing a variable structure adaptive backstepping controller (VS-ABC) by using state observers for SISO (Single Input Single Output), linear and time invariant systems with relative degree one. Therefore, the lters were replaced by a Luenberger Adaptive Observer and the control algorithm uses switching laws. The presented simulations compare the controller performance, considering when the state variables are estimated by an observer, with the case that the variables are available for measurement. Even with numerous performance advantages, adaptive backstepping controllers still have very complex algorithms, especially when the system state variables are not measured, since the use of lters on the plant input and output is not something trivial. As an attempt to make the controller design more intuitive, an adaptive observer as an alternative to commonly used K lters can be used. Furthermore, since the states variables are considered known, the controller has a reduction on the dependence of the unknown plant parameters on the design. Also, switching laws could be used in the controller instead of the traditional integral adaptive laws because they improve the system transient performance and increase the robustness against external disturbances in the plant input

A democracia participativa na jurisdição constitucional brasileira: o amicus curiae enquanto mediador democrático no controle concentrado de constitucionalidade no Supremo Tribunal Federal

This master thesis aims to research the tension established between the judicial review and democratic theory which was always present in the constitutional doctrine of separation of powers. In this regard, the expansion of the Brazilian constitutional jurisdiction checked after the occurrence of the Federal Constitution of 1988 and the inertia of the Legislature in disciplinary relevant legal aspects of Brazilian society contributed to a hyperactivity of the Supreme Court. However, in a complex society of context, as is the Brazilian society, there are contained demands and political controversies that hardly would be well represented or resolved through the action of the Court of ministers at the expense of other government bodies. Among the supremacy of Parliament and the legitimacy deficit of these magistrates, is the constitutional text and the social fabric that makes this legal status of the political. Participatory democracy established by the guidelines of the Federal Constitution requires this perspective when the Supreme Court acting in place of concentrated constitutionality control. In a plural society, there is no reason to get rid of state decision moments popular participation. Lack the Supreme Court, this time, the democratizing perception that the institute brings to the interior of the Court, as state determination of space in which to come together and meet the aspirations of society and state claims. The dissertation investigates thus the possibility of amicus curiae Institute serve as a mediator of the democratic debate, to assist the Supreme Court in the preparation of the decision is, historically, that which is of greater legitimacy, from the perspective of a theory participatory democracy. Analyzes, likewise, the unfolding of abstract judicial review in the context of Brazilian law. Proposes, incidentally, a rereading of the separation of powers, with the call for the Judiciary be careful not to become the protagonist of national political decisions. It maintains, finally, that procedural opening the interpreters of the constitution, through the amicus curiae Institute, shows up as able to decrease the legitimacy deficit in the performance of the Brazilian Supreme Court.