Regulador automático de tensão robusto utilizando técnicas de controle adaptativo

The stability of synchronous generators connected to power grid has been the object of study and research for years. The interest in this matter is justified by the fact that much of the electricity produced worldwide is obtained with the use of synchronous generators. In this respect, studies have been proposed using conventional and unconventional control techniques such as fuzzy logic, neural networks, and adaptive controllers to increase the stabilitymargin of the systemduring sudden failures and transient disturbances. Thismaster thesis presents a robust unconventional control strategy for maintaining the stability of power systems and regulation of output voltage of synchronous generators connected to the grid. The proposed control strategy comprises the integration of a sliding surface with a linear controller. This control structure is designed to prevent the power system losing synchronism after a sudden failure and regulation of the terminal voltage of the generator after the fault. The feasibility of the proposed control strategy was experimentally tested in a salient pole synchronous generator of 5 kVA in a laboratory structure

Contribuições ao método de rastreamento de máxima potência para sistemas fotovoltaicos

The scarcity of natural resources and the search for alternative energy sources promote a rapid change in the energy world. Among the renewable energy sources, solar energy is the most promising, presenting technology of greatest growth rate nowadays. Researchers around the world are seeking ways to facilitate their progress, developing technologies with higher efficiency and lower cost. As a contribution to global progress, this master thesis proposes the development of a strategy of maximum power tracking based on perturbation and observation method for photovoltaic systems. The proposed control strategy is based on active power balance of the system, with a reduced number of sensors. It also allows the PV system to act as a regulator of the power quality at the point of commom coupling (PCC), compensating the harmonic distortion and power factor of the current netw

Controle automático para injeção otimizada de gás em poços de petróleo equipados para funcionamento com gás lift contínuo

The continuous gas lift method is the main artificial lifting method used in the oil industry for submarine wells, due to its robustness and the large range of flow rate that the well might operate. Nowadays, there is a huge amount of wells producing under this mechanism. This method of elevation has a slow dynamics due to the transients and a correlation between the injected gas rate and the of produced oil rate. Electronics controllers have been used to adjust many parameters of the oil wells and also to improve the efficiency of the gas lift injection system. This paper presents a intelligent control system applied to continuous gas injection in wells, based in production s rules, that has the target of keeping the wells producing during the maximum period of time, in its best operational condition, and doing automatically all necessary adjustments when occurs some disturbance in the system. The author also describes the application of the intelligent control system as a tool to control the flow pressure in the botton of the well (Pwf). In this case, the control system actuates in the surface control valve

Desenvolvimento de protótipo de coletor automático destinado à coleta de amostras de água em corpos aquáticos para análise em laboratório

The aim of this approach is to describe the design and construction of a low-cost automated water sampler prototype. In recent years, there is an increasing need on the use of automated equipments for hydro climatic variables to be use in urban and rural environments. Such devices are always used to provide measured information which is of crucial importance on the development of water resources strategies at watershed scale. Actually, many research and water public institutions have been using these kinds of equipments. In most of the cases, automated equipments are expensive and need to be imported, generating a situation of technologic dependency. The prototype is based on an electronic system which controls a peristaltic pump functioning, five solenoid valves and an ultrasonic sensor connected to a datalloger. An interface with the user allows communication with a PC, when the equipment functioning parameters can be provided. The equipment has a hydraulic module composed by a 12V peristaltic pump connected to a distribution circuit composed by five solenoid valves, one of them being used to clean the circuit before each sampling procedure. Samples are collected by four 1.95 polyethylene bottles. The sampler body was made of acrylic material, with a cylindrical shape, and dimensions 0.72 m and 0.38 m height and diameter, respectively. The weight of the equipment without samples is approximately 15 kg, which infers to its portability. The prototype development total cost budget was approximately US$ 1,560.00. Laboratory tests aimed to evaluate the equipment performance and functioning demonstrated satisfactory results

Essas pessoas na sala de jantar : espaços históricos em canções tropicalistas (1963-1973)

Tropicalia concerns the attempt of understanding of Brazil and a national identity characterized by the transience of time and space, rhizomatic action, perpetual laceration of cultural boundaries and at the same time act synchronously to instances such as policy and the social. A word created by artist Hélio Oiticica and registered by him on the National Register of Trademarks and Patents, was later used to a name the eponymous song by Caetano Veloso and also in this fertile cultural impulse at the turn of the sixties to the seventies on last century, who had the intention to make creating new spaces and simultaneously rethink the spatial cuts of Brazilian culture, encouraging them to be much more than a myth of a paradise within a lush new look of a tropical truth.

Pessoas com deficiência no mercado de trabalho: considerações sobre políticas públicas nos Estados Unidos, União Europeia e Brasil

Atualmente, discussões a respeito da construção de uma sociedade inclusiva, ou seja, responsiva às diferenças, têm ocorrido em diversos países. de acordo com os princípios da inclusão social, a participação das pessoas com deficiência na sociedade depende de profundas transformações, cabendo à sociedade prover os suportes necessários para que esses indivíduos tenham acesso a todos os recursos disponíveis no meio social e, além disso, ao convívio de maneira não-segregada. Uma questão importante, nesse sentido, é a elaboração de políticas públicas no âmbito do trabalho voltadas para pessoas com deficiência. Embora o acesso ao trabalho seja considerado um dos principais direitos civis dos indivíduos, as pessoas com deficiência ainda encontram diversas barreiras para ingressar no mercado profissional. Partindo dessas afirmações, este artigo teve como objetivo discutir alguns dos principais aspectos das políticas de emprego adotadas nos Estados Unidos, na União Europeia e no Brasil para favorecer a inserção desses indivíduos no mercado de trabalho. Para tanto, três documentos legais, sendo um Nacional, um procedente dos Estados Unidos e outro, da União Europeia, foram analisados quanto aos itens: a) ano de publicação do documento; b) objetivos; c) definição de deficiência; e d) estratégias de inserção da pessoa com deficiência no mercado de trabalho. A partir das considerações realizadas, pode-se dizer que existem avanços e divergências nas políticas de emprego e que estas estão relacionadas às particularidades de cada um dos contextos; no entanto, existe uma preocupação comum em garantir à pessoa com deficiência o ingresso na atividade profissional.

Comportamento sócio-espacial de pessoas em movimento :um estudo exploratório no calçadão da Avenida Engenheiro Roberto Freire

People-environment interaction, focus of Environmental Psychology studies, presupposes that space influences behavior and vice-versa. Despite of the importance of dynamic reciprocity, there are a few works that treat the mobility condition of the people experimenting space. The present study investigates environmental perception of users of the Engenheiro Roberto Freire Avenue sidewalk, one of the few places in Natal for physical activities practicing, where most people are in intense and continuous movement. A few questions for this study where made: In what way does the individual realize the environment while he is moving? How do reciprocal man-environment relations occur there, according to a mobility context? What are the main difficulties and easiness in man-environment interaction under this condition? The search for these answers is based on concepts of social-spatial human behavior - especially personal space, territoriality, density and crowding and contributions of Barker´s Ecologycal Psychology. Considering that the physical space in this case is multifaceted and the perception of theses scenarios is governed by multiples senses and stimuli, it was defined a multi-methodological route: (i) observation participative in loco; (ii) identification of the main behavior settings at the area; (iii) categorization of the activities occurring at the place; (iv) application of a semi-structured interview; (v) images registered and (vi) construction of the researcher s log. The perception of oneself and others in movement in the environment, immersed in a intricate web of inter-actions, makes people develop mobility strategies, many times unconsciously, with the aim of ensuring satisfaction in its activities. Since the Eng. Roberto Freire Avenue sidewalk is an equipment public-urban largely used by the population of Natal, the reflection of the mobility effectiveness in the users environmental perception is expected, providing suggestions for future studies in this field of knowledge

Compreendendo a experiência de pessoas portadoras de transtorno mental: histórias de vidas severinas repletas de possibilidades

This study aims to understand the experience of people suffering from mental disorder. The patients are enrolled in a mental health ambulatory clinic in the city of Natal (RN). Mental disorders are growing rapidly in the contemporary world and are a source of intense mental suffering. Besides patients being strongly marked by a history of isolation and prejudice, they have been the target of real atrocities committed in the name of preservation of a supposed normality. The understanding and treatment of this disorder is influenced by cultural and historical inferences, depending on the period in which it is experienced. Semi-directed Interviews were conducted with a group of users, with the emphasis on giving voice to their uniqueness and individuality, highlighting how each one perceives his or her own experience. These were recorded and later transcribed by identifying the core of meanings. The results were analyzed under the gaze of the Humanist Phenomenology Existential perspective, which aims to unravel the phenomenon, without truths from volatility, highlighting the existence of the mental disorder as a way of living, being permeated by suffering mental and influenced by social problems, assuming contours very particular to each individual. Some progress has been perceived, even by users, with respect to the change of paradigm in the way of care, but still there is a consistent emphasis on medical and drug use. The changes point to the need for offering services to replace the asylum hospital model, and in addition to accept the bearer of mental disorder as a citizen, a bearer of rights who should be accepted and respected by society. Despite the pain expressed and its close liaison with suicide, their reports are full of perspectives and attitudes of confrontation facing life, pointing to new possibilities to be, recreating itself

Metodologia para rastreamento com modificação dos zeros e rejeição de distúrbio aplicada a sistemas incertos

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Controle ótimo H2 e H¥ com modificação de zeros para o problema de rastreamento usando LMI

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

As pessoas com deficiência no mercado de trabalho: expressão das desigualdades sociais

This work was developed in the extent of the Post Graduation Program in Social Service of the Federal University of Rio Grande do Norte. It talks about the process of inclusion of the disabled people in the Job market in Mossoró-RN, bringing for the academic debate relevant thematic for the Brazilian society, for the profession of Social Service and similar areas and for the people with deficiency. It has the objective to apprehend the determiners that make possible the process of the disabled people's inclusion in the Job market in Mossoró, having as parameter the National Politics for the Integration of People Bearers of Deficiency. The critical theoretical perspective is backed in Marx's ideas for the understanding concerning the work, as well as in Pochamann, concerning the job market, regarding the exclusion/inclusion category is based in Martins, Yasbek and Sposati and on deficiency in the National Politics for the Integration of the Disabled People. The research is of qualitative nature and it took as subjects 26 (twenty-six) people, being 09 (nine) people with deficiency, inserted in the formal job and regulated market, and 17 (seventeen) managers of private companies and public institutions of the city of Mossoró-RN. For the collection of data we used techniques of nonsystemic observation, semi-structured interview and documental analysis. The results of the research mark that any modality of the human workforce used in the current context, they are functional to the capitalism and they move forward towards exploration, alienation and subordination of the work to the capital; the National Politics for the Integration of the People with Deficiency expresses and reproduces the contradictory dynamics of the class society, it reflects the neo liberal shades through the selectivity and of the articulation among the federated beings and organizations of the civil society for its operational system; there is a misproportion between the percentages of the quotas and the amount of people with deficiency inserted in the job market, just corresponding to a tiny numeric magnitude; the developed activities are of low social status and it is expressive the amount of workers that receives between one and two minimum wages. These data drive us to infer that the mentioned politics make possible, partly, the inclusion of the disabled people in the job market, though, such inclusion is executed in the selective or focused dimensions, marginal, precarious and unstable

Corpo, doença e biomedicina: uma análise antropológica de práticas corporais e de tratamento entre pessoas com HIV/AIDS

A epidemia do HIV/AIDS tem desafiado tanto a biomedicina como a ciência de modo geral. Tecnologias vêm sendo exploradas a fim de criar uma base terapêutica consistente às pessoas infectadas. Se os tratamentos exigem o consumo diário de medicamentos, os exames laboratoriais contemplam uma rotina a ser sempre mantida. Levam a um processo de mudança e adaptação pessoal junto de uma reorganização intensiva das formas de cuidado do corpo. As práticas clínico-terapêuticas devem ser entendidas, porém, como elementos particulares de processos culturais de grande alcance. Partindo de pesquisa etnográfica no Rio de Janeiro, discuto os efeitos sociais da biomedicina como um saber e uma cultura global sobre práticas sociais locais.

Doença, ativismo biossocial e cidadania terapêutica: a emergência da mobilização de pessoas com HTLV no Brasil

O artigo aborda a emergência da mobilização social e política de pessoas infectadas pelo HTLV, na década de 2000. Com fortes vínculos com o ativismo de HIV/Aids, pessoas com HTLV e seus grupos e organizações engendraram práticas sociais, discursos e identidades que contribuem para se pensar em termos teóricos e históricos sobre a questão das biossocialidades e da cidadania terapêutica

O significado do trabalho em equipe na reabilitação de pessoas com malformação craniofacial congênita

Este estudo objetivou compreender o significado do trabalho em equipe dos profissionais de reabilitação em anomalias craniofaciais. Realizou-se análise fenomenológica por contemplar a compreensão e interpretação do sentido considerando o sujeito. Entrevistou-se 12 profissionais de diferentes áreas, norteadas pela questão: O que significa para você trabalhar em equipe na reabilitação de anomalias craniofaciais? Resgatando-se os temas: Capacitação para o trabalho, Dificuldade para trabalho em equipe, Relação com paciente e família, Condições de trabalho e A inserção do profissional na equipe. A análise visou refletir o fenômeno engendrando convergências e divergências destacando a explicitação das diferenças e aprendizado contínuo.