930 resultados para Power Flow Control, Radial Distribution System, Distributed Generator (DG)
Resumo:
This paper presents a virtual headstick system as an alternative to the conventional passive headstick for persons with limited upper extremity function. The system is composed of a pair of kinematically dissimilar master-slave robots with the master robot being operated by the user's head. At the remote site, the end-effector of the slave robot moves as if it were at the tip of an imaginary headstick attached to the user's head. A unique feature of this system is that through force-reflection, the virtual headstick provides the user with proprioceptive information as in a conventional headstick, but with an augmentation of workspace volume and additional mechanical power. This paper describes the test-bed development, system identification, bilateral control implementation, and system performance evaluation.
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The formation of complexes in solutions containing positively charged polyions (polycations) and a variable amount of negatively charged polyions (polyanions) has been investigated by Monte Carlo simulations. The polyions were described as flexible chains of charged hard spheres interacting through a screened Coulomb potential. The systems were analyzed in terms of cluster compositions, structure factors, and radial distribution functions. At 50% charge equivalence or less, complexes involving two polycations and one polyanion were frequent, while closer to charge equivalence, larger clusters were formed. Small and neutral complexes dominated the solution at charge equivalence in a monodisperse system, while larger clusters again dominated the solution when the polyions were made polydisperse. The cluster composition and solution structure were also examined as functions of added salt by varying the electrostatic screening length. The observed formation of clusters could be rationalized by a few simple rules.
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The absorption spectra of phytoplankton in the visible domain hold implicit information on the phytoplankton community structure. Here we use this information to retrieve quantitative information on phytoplankton size structure by developing a novel method to compute the exponent of an assumed power-law for their particle-size spectrum. This quantity, in combination with total chlorophyll-a concentration, can be used to estimate the fractional concentration of chlorophyll in any arbitrarily-defined size class of phytoplankton. We further define and derive expressions for two distinct measures of cell size of mixed populations, namely, the average spherical diameter of a bio-optically equivalent homogeneous population of cells of equal size, and the average equivalent spherical diameter of a population of cells that follow a power-law particle-size distribution. The method relies on measurements of two quantities of a phytoplankton sample: the concentration of chlorophyll-a, which is an operational index of phytoplankton biomass, and the total absorption coefficient of phytoplankton in the red peak of visible spectrum at 676 nm. A sensitivity analysis confirms that the relative errors in the estimates of the exponent of particle size spectra are reasonably low. The exponents of phytoplankton size spectra, estimated for a large set of in situ data from a variety of oceanic environments (~ 2400 samples), are within a reasonable range; and the estimated fractions of chlorophyll in pico-, nano- and micro-phytoplankton are generally consistent with those obtained by an independent, indirect method based on diagnostic pigments determined using high-performance liquid chromatography. The estimates of cell size for in situ samples dominated by different phytoplankton types (diatoms, prymnesiophytes, Prochlorococcus, other cyanobacteria and green algae) yield nominal sizes consistent with the taxonomic classification. To estimate the same quantities from satellite-derived ocean-colour data, we combine our method with algorithms for obtaining inherent optical properties from remote sensing. The spatial distribution of the size-spectrum exponent and the chlorophyll fractions of pico-, nano- and micro-phytoplankton estimated from satellite remote sensing are in agreement with the current understanding of the biogeography of phytoplankton functional types in the global oceans. This study contributes to our understanding of the distribution and time evolution of phytoplankton size structure in the global oceans.
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This report presents a new way of control engineering. Dc motor speed controlled by three controllers PID, pole placement and Fuzzy controller and discusses the advantages and disadvantages of each controller for different conditions under loaded and unloaded scenarios using software Matlab. The brushless series wound Dc motor is very popular in industrial application and control systems because of the high torque density, high efficiency and small size. First suitable equations are developed for DC motor. PID controller is developed and tuned in order to get faster step response. The simulation results of PID controller provide very good results and the controller is further tuned in order to decrease its overshoot error which is common in PID controllers. Further it is purposed that in industrial environment these controllers are better than others controllers as PID controllers are easy to tuned and cheap. Pole placement controller is the best example of control engineering. An addition of integrator reduced the noise disturbances in pole placement controller and this makes it a good choice for industrial applications. The fuzzy controller is introduce with a DC chopper to make the DC motor speed control smooth and almost no steady state error is observed. Another advantage is achieved in fuzzy controller that the simulations of three different controllers are compared and concluded from the results that Fuzzy controller outperforms to PID controller in terms of steady state error and smooth step response. While Pole placement controller have no comparison in terms of controls because designer can change the step response according to nature of control systems, so this controller provide wide range of control over a system. Poles location change the step response in a sense that if poles are near to origin then step response of motor is fast. Finally a GUI of these three controllers are developed which allow the user to select any controller and change its parameters according to the situation.
Resumo:
Objective: For the evaluation of the energetic performance of combined renewable heating systems that supply space heat and domestic hot water for single family houses, dynamic behaviour, component interactions, and control of the system play a crucial role and should be included in test methods. Methods: New dynamic whole system test methods were developed based on “hardware in the loop” concepts. Three similar approaches are described and their differences are discussed. The methods were applied for testing solar thermal systems in combination with fossil fuel boilers (heating oil and natural gas), biomass boilers, and/or heat pumps. Results: All three methods were able to show the performance of combined heating systems under transient operating conditions. The methods often detected unexpected behaviour of the tested system that cannot be detected based on steady state performance tests that are usually applied to single components. Conclusion: Further work will be needed to harmonize the different test methods in order to reach comparable results between the different laboratories. Practice implications: A harmonized approach for whole system tests may lead to new test standards and improve the accuracy of performance prediction as well as reduce the need for field tests.
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The crisis that affected the capitalist states during the last decade of the 20th century, put an end to the period of greatest expansion of the state, demanding alterations that brought, especially in economic terms, the ideals of the liberal state. The main goal of these changes was to optimize the administration of the public service by introducing into it more efficiency, transparency, and morality because the state had shown to be incapable of attending the demands of the society and its way of doing was inefficient and did not reach out to the public interest. In Brazil, like in other part of the world, recent scandals of corruption and misuse of public funds put in doubt the efficiency of the financial control system. Like any other political system Brazil has a complex set of external and internal control, institutions that work to prevent misuse of public funds and identify responsibilities if bad use occurred. All these elements highlight the mechanisms of control of the public administration, which came to be seen as essential instruments for the improvement of the management of the public resources, targeting the collective interest. Therefore, along with the traditional mechanisms of power suppression, such as the system of checks and balances, social control arises. This, when used together with the monitoring exercised by public inspection agencies, is defined as horizontal accountability activated by civil society, in which citizens and institutions gather efforts in order to promote a more effective charge of responsibility from public agents and politicians in case of misconducts. This study aimed to identify the opportunities and limitations of social control exercised by the complaint under the TCE-RJ. The results point to the need to develop measures to guarantee the anonymity of denouncers, to simplify the forms of access the TCE-RJ and to improve information spread to the citizen.
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This academic work describes the interfirm technological learning processes behavior at a thermo plant throughout the years 2001 till 2007. Its former ownership structure was composed by two foreigners companies. This structure was changed by the acquisition of the company control by a Brazilian state owned company on April 2006. The company is a Natural Gas Fired Power Plant placed at Macaé City, at Rio de Janeiro State, Brazil generating electric power right to National Integrated System (SIN). The goal of this research is verify how the technological knowledge had been acquired by the firm and how it had been spread out throughout the organization before and after the change of the ownership structure. The taxonomy applied to determining of ownership structure take in account three parameters: type, specific characteristic and the ownership structure itself. Technological Learning Interfirm Processes have been examined from a model of systemic approach that establishes four key characteristics: ¿variety, intensity, functioning and interaction¿. During 2001 until 2006, till the change of owner structure, the firm developed its own learning processes in its own operational routines. The main learning processes have been identified from empirical evidences. It has been adopted the cut line at year of 2006 for the comparison among the technological learning processes behavior, when the change of ownership structure took place. The data capture occurred within April and August 2007 covering since 2001. Verified the behavior of these learning processes before and after the ownership structure changed from private property to state owned property. The conclusion of this case study suggests that interfirm processes of technological learning identified by the research had their dynamical behavior promptly affected by a change from private to ownerstate ownership structure, exposing the company to a poor performance in its industry, due to the lack of 51% of the technological intrafirm learning processes and reduction of the acquisition of new technical knowledge and its conversion throughout the organization.
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Esta dissertação tem como objetivo principal analisar a forma como os líderes de uma organização que alavanca suas atividades com uma estrutura em rede, transmitem a cultura da empresa central junto às empresas periféricas. Pretende-se investigar também se os líderes mudaram o seu papel em função da mudança da arquitetura organizacional no período considerado por alguns autores como pós-moderno. Como o tema cultura é amplo e complexo, optou-se por enfocar aspectos como a transmissão da missão e objetivos organizacionais, além do estilo de gestão predominante e sua influência no gerenciamento de projetos entre os protagonistas dessas diferentes organizações. Utilizou-se, para tanto, uma base teórico-empírica que buscou definir o conceito de cultura através do estudo do universo simbólico; a questão da liderança e sua relação com estruturas e fontes de poder e controle nas organizações; cultura e liderança no contexto brasileiro; e, por último, o conceito de organizações em rede, explorando também os aspectos de gestão, poder e controle esperado nesse tipo de arquitetura organizacional. Esta pesquisa constitui-se num estudo de caso realizado em uma instituição sem fins lucrativos, que desenvolve projetos sociais com foco em educação. Trata-se de um estudo exploratório, descritivo e explicativo. O método utilizado para a presente pesquisa foi o método qualitativo. Muitos estudos sobre cultura organizacional privilegiam o enfoque qualitativo de pesquisa, uma vez que um grande número de observações não é passível de quantificação. Utilizou-se a técnica de observação participante e de entrevistas semi-estruturadas, além da análise documental, o que possibilitou uma investigação que envolveu a combinação de descrição com interpretação do conteúdo trazido pelos respondentes em relação aos fenômenos observados. Os dados obtidos e a análise realizada frente à fundamentação teórica, indicam que o líder em uma organização em rede transmite a cultura organizacional com o mesmo discurso dominante das organizações com estruturas tradicionais. Acredita-se que este trabalho despertará interesse da comunidade acadêmica, uma vez que os aspectos culturais são normalmente pesquisados dentro da organização e aqui se ressalta a importância de se analisar o contexto no qual a organização está inserida e o papel que o líder assume na gestão das atividades realizadas por terceiros. Estaria o gestor brasileiro disposto a abrir mão do poder e controle que a posição hierárquica lhe confere para trabalhar em uma relação de igualdade com representantes de outras organizações?
Resumo:
Em virtude da ocorrência do fenômeno da globalização inúmeras sociedades passaram a ter seu controle exercido por outras pertencentes ao mesmo grupo econômico. Com o surgimento destas estruturas societárias hierarquizadas foi constatado um significativo crescimento no número de atos realizados com desvio ou abuso de poder por parte do detentor deste poder de comando, os quais dão ensejo, a priori, a caracterização do abuso de poder de controle. Os atos realizados com as características supracitadas podem ser encontrados em contratos de empréstimos celebrados entre sociedades pertencentes ao mesmo grupo econômico. Entretanto, cabe salientar que nem todos os contratos desta natureza devem ser vistos como sendo abusivos, ou seja, existem contratos envolvendo estes pares que podem ser considerados lícitos e legítimos. Diante desta constatação, serão analisadas através de um caso gerador as peculiaridades que um contrato de empréstimo envolvendo sociedades do mesmo grupo econômico necessita apresentar para que o mesmo seja considerado licito, e com isso o ato realizado pelo detentor do poder de controle não seja considerado abusivo. Por fim, poderemos diferenciar os contratos de empréstimos envolvendo sociedades do mesmo grupo econômico que deverão ser considerados como sendo lícitos e legítimos, dos contratos que acarretam prejuízos aos acionistas minoritários, ao mercado, bem como toda a sociedade, e que, portanto, deverão ser considerados abusivos.
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Este estudo procura descer aos pormenores da situação operacional para conhecer as causas que o levam a ser o que é; sua operação organizacional, diretrizes e métodos de operação. O foco do nosso trabalho é diretamente entre a periferia do centro urbano de Brasília, as Cidades Satélites, distantes de uns poucos a várias dezenas de quilômetros da mesma, surgidas da necessidade de abrigar a população vizinha à parte planejada, o plano piloto, como se chamou posteriormente.
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As organizações estão conscientes que enfrentarão complexa mudança organizacional, pois as demandas individuais na participação das decisões têm alterado os papéis desempenhados pelos gestores e seus subordinados. Neste contexto, a comunicação torna-se essencial para o exercício da influência social, para a coordenação das atividades e para a efetivação da liderança. A literatura aponta que as atitudes e os comportamentos dos funcionários são regidos por uma distribuição justa das recompensas conforme às contribuições de cada um. Assim, satisfação e atitudes positivas podem ser alcançadas por meio de um ambiente organizacional com boa comunicação, autonomia, participação, justiça distributiva e confiança. Portanto, este trabalho teve o objetivo de identificar as dimensões de Liderança e Cultura Organizacional na Criminalística da Polícia Federal, suas relações com o Clima Organizacional e como estes construtos contribuem para explicação dos problemas gerenciais. Para a coleta dos dados, foi realizada uma pesquisa quantitativa composta de 4 questionários. Dos 722 formulários enviados, 150 (20,8 %) foram respondidos: 21 (14 %) por Peritos Criminais Federais (PCF) do órgão central, 126 (84 %) por PCF das descentralizadas e 3 (2 %) por PCF de outras unidades. Os entrevistados tinham de 30 a 64 anos de idade (μ = 40,9; dp = 6,8), de 1 a 32 anos de serviço público (μ = 12,6; dp = 6,5) e de 1 a 27 anos de nomeação (μ = 7,9; dp = 3,9), e a função de chefia foi exercida por 79 (52,7 %) respondentes. Os resultados revelaram que não há diferença nas percepções de Liderança, Cultura e Clima Organizacional entre as regiões do país, rejeitando a hipótese H6 deste trabalho. Em um estudo longitudinal entre 2011 e 2013 também não houve mudanças significativas na percepção de Liderança, mostrando consistência entre as populações. Além disso, os resultados mostraram que a idade, o tempo de trabalho e o tempo de nomeação não estão associados com o Clima, logo servidores de diferentes épocas têm a mesma percepção do clima da organização. Os modelos de equações estruturais demonstraram que a Liderança, as Práticas de Liderança e o Clima são explicados fortemente por suas dimensões, e que a Cultura Organizacional afeta a Liderança e as Práticas de Liderança porém, mais significativamente, o Clima Organizacional. Tais resultados corroboram a teoria e explicam hipóteses deste trabalho. Observou-se, também, que na organização há predomínio da subcultura burocrática, baseada em controle e poder, que impacta o Clima Organizacional e, frequentemente, resulta em menor comprometimento e desempenho do servidor. A pesquisa apontou que os líderes devem encorajar a comunicação aberta para alcançar o entendimento dialógico na organização. Os achados deste estudo podem fornecer à gestão uma visão melhor para gerir seus recursos com base na legitimidade, na referência, no conhecimento e na informação, obedecendo os pressupostos do discurso ideal habermasiano.
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The intention of this thesis is to develop a prototype interface that enables an operator to control a bi-wheeled industrial hovercraft that will work within a fusion power plant if the automation system fails. This fusion power plant is part of the ITER project a conjoint effort of various industrialized countries to develop cleaner sources of energy. The development of the interface prototype will be based on situation awareness concepts, which provide a means to understand how human operators perceive the world around, then process that information and make decisions based on the knowledge that they already have and the projected knowledge of the reactions that will occur in the world in response to the actions the operator makes. Two major situation awareness methods will be used, GDTA as a means to discover the requirements the interface needs to solve, and SAGAT to conduct the evaluation on the three interfaces. This technique can isolate the differences an operator has in situation awareness when presented with relevant information given by each of the three interfaces that were built for this thesis. Where the first interface presents the information within the operator’s focal point of view in a pictorial style, the second interface shows the same information within the same point of view has the first interface but only shows it in a textual manner. While the third interface shows the relevant information in the operator’s peripheral field of view. Also SAGAT can provide insight on the question to know if providing the operator with feed-forward information about the stoppage distances of the bi-wheeled industrial hovercraft has any effect on the operator’s decision making.
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The right against self-incrimination is a fundamental right that works in the criminal prosecution, and therefore deserves a study supported by the general theory of criminal procedure. The right has a vague origin, and despite the various historical accounts only arises when there is a criminal procedure structured that aims to limit the State´s duty-power to punish. The only system of criminal procedure experienced that reconciles with seal self-incrimination is the accusatory model. The inquisitorial model is based on the construction of a truth and obtaining the confession at any cost, and is therefore incompatible with the right in study. The consecration of the right arises with the importance that fundamental rights have come to occupy in the Democratic Constitutional States. In the Brazilian experience before 1988 was only possible to recognize that self-incrimination represented a procedural burden for accused persons. Despite thorough debate in the Constituent Assembly, the right remains consecrated in a textual formula that´s closer to the implementation made by the Supreme Court of the United States, known as "Miranda warnings", than the text of the Fifth Amendment to the U.S. Constitution that established originally the right against self-incrimination with a constitutional status. However, the imprecise text does not prevent the consecration of the principle as a fundamental right in Brazilian law. The right against self-incrimination is a right that should be observed in the Criminal Procedure and relates to several of his canons, such as the the presumption of not guilty, the accusatory model, the distribution of the burden of proof, and especially the right of defense. Because it a fundamental right, the prohibition of self-incrimination deserves a proper study to her constitutional nature. For the definition of protected persons is important to build a material concept of accused, which is different of the formal concept over who is denounced on the prosecution. In the objective area of protection, there are two objects of protection of the norm: the instinct of self-preservation of the subject and the ability to self-determination. Configuring essentially a evidence rule in criminal procedure, the analysis of the case should be based on standards set previously to indicate respect for the right. These standard include the right to information of the accused, the right to counsel and respect the voluntary participation. The study of violations cases, concentrated on the element of voluntariness, starting from the definition of what is or is not a coercion violative of self-determination. The right faces new challenges that deserve attention, especially the fight against terrorism and organized crime that force the development of tools, resources and technologies about proves, methods increasingly invasive and hidden, and allow the use of information not only for criminal prosecution, but also for the establishment of an intelligence strategy in the development of national and public security
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Os objetivos deste trabalho foram quantificar as exposições dérmicas (EDs) e respiratórias (ERs) proporcionadas ao piloto e ao seu ajudante nas aplicações de herbicidas para o controle de plantas daninhas aquáticas com aerobarco; classificar essas condições de trabalho em seguras ou inseguras; e calcular a necessidade de controle das exposições (NCE) e o tempo de trabalho seguro (TTS). O aerobarco utilizado tinha casco de alumínio (4,85 x 2,42 m) e acionamento por hélice acoplada a motor a gasolina de 350 HP. O equipamento de pulverização era composto por bomba de diafragma com fluxo máximo de 49,69 L min-1, pressão máxima de 25 kg cm-2, acionada por motor a gasolina de 4 HP, e tanque de calda de 189 L. A barra de pulverização de alumínio era composta de duas seções laterais de 3 m, posicionadas na linha entre o encosto do banco do piloto e o início da estrutura protetora da hélice. Cada seção da barra tinha seis bicos com pontas de jato plano com indução de ar AI 100 03, espaçados de 0,5 m, e uma ponta OC 20 fixada em cada extremidade. O conjunto de pontas pulverizava faixas de 6 m de largura e aplicava o volume de calda de 200 L ha-1. O sistema tinha gerenciador de fluxo, controlado por central eletrônica acoplada a DGPS (com precisão submétrica), para corrigir automaticamente a vazão em função de alterações na velocidade real da embarcação. As EDs e ERs aos herbicidas foram calculadas com os dados substitutos das exposições às caldas, avaliadas com os traçadores cobre e manganês adicionados às caldas. As exposições foram extrapoladas para uma jornada de trabalho de seis horas. A segurança das condições de trabalho foi determinada com o cálculo da margem de segurança (MS), utilizando-se a fórmula MS = (NOEL x 70)/(QAE x 10), em que QAE = quantidade absorvível da exposição. As condições de trabalho foram classificadas em seguras, se MS>1, ou inseguras, se MS<1. As exposições proporcionadas pelas condições de trabalho foram de 10,65 mL de calda por dia para o piloto e de 16,80 mL por dia para o ajudante, que fica sentado em uma cadeira a 2,0 m à frente do piloto e da barra de pulverização. Classificaram-se como seguras as aplicações dos herbicidas glyphosate (Rodeo, 6 L ha-1), 2,4D (DMA 806 BR, 8 L ha-1) e fluridone (Sonar AQ, 0,4 L ha-1), para o piloto e o seu ajudante. Classificou-se como insegura a aplicação do herbicida diquat (Reward, 4,0 L ha-1) para as duas condições de trabalho, cujas necessidades de controle das exposições calculadas foram de 65% para o piloto e de 78% para o ajudante do piloto.
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The sanitation companies from Brazil has a great challenge for the XXI century: seek to mitigate the rate of physical waste (water, chemicals and electricity) and financial waste caused by inefficient operating systems drinking water supply, considering that currently we already face, in some cases, the scarcity of water resources. The supply systems are increasingly complex as they seek to minimize waste and at the same time better serve the growing number of users. However, this technological change is to reduce the complexity of the challenges posed by the need to include users with higher quality and efficiency in services. A major challenge for companies of water supplies is to provide a good quality service contemplating reducing expenditure on electricity. In this situation we developed a research by a method that seeks to control the pressure of the distribution systems that do not have the tank in your setup and the water comes out of the well directly to the distribution system. The method of pressure control (intelligent control) uses fuzzy logic to eliminate the waste of electricity and the leaks from the production of pumps that inject directly into the distribution system, which causes waste of energy when the consumption of households is reduced causing the saturation of the distribution system. This study was conducted at Green Club II condominium, located in the city of Parnamirim, state of Rio Grande do Norte, in order to study the pressure behavior of the output of the pump that injects water directly into the distribution system. The study was only possible because of the need we had to find a solution to some leaks in the existing distribution system and the extensions of the respective condominium residences, which sparked interest in developing a job in order to carry out the experiments contained in this research