1000 resultados para Método da convergência-confinamento


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A 2.5D ray-tracing propagation model is proposed to predict radio loss in indoor environment. Specifically, we opted for the Shooting and Bouncing Rays (SBR) method, together with the Geometrieal Theory of Diffrartion (GTD). Besides the line-of-sight propagation (LOS), we consider that the radio waves may experience reflection, refraction, and diffraction (NLOS). In the Shooting and Bouncing Rays (SBR) method, the transmitter antenna launches a bundle of rays that may or may not reach the receiver. Considering the transmitting antenna as a point, the rays will start to launch from this position and can reach the receiver either directly or after reflections, refractions, diffractions, or even after any combination of the previous effects. To model the environment, a database is built to record geometrical characteristics and information on the constituent materials of the scenario. The database works independently of the simulation program, allowing robustness and flexibility to model other seenarios. Each propagation mechanism is treated separately. In line-of-sight propagation, the main contribution to the received signal comes from the direct ray, while reflected, refracted, and diffracted signal dominate when the line-of-sight is blocked. For this case, the transmitted signal reaches the receiver through more than one path, resulting in a multipath fading. The transmitting channel of a mobile system is simulated by moving either the transmitter or the receiver around the environment. The validity of the method is verified through simulations and measurements. The computed path losses are compared with the measured values at 1.8 GHz ftequency. The results were obtained for the main corridor and room classes adjacent to it. A reasonable agreement is observed. The numerical predictions are also compared with published data at 900 MHz and 2.44 GHz frequencies showing good convergence

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The transmedia storytelling is a phenomenom recently conceptualized theoretically (JENKINS, 2009), arising from ficcional mediatic products and disseminated as well by the use on other fields. This search aims to analyze how the transmedia storytellings can be applied to journalism on the basis of an specific genre, the reporting. To that, take as reference theoretical developments performed by brazilian authors (FECHINE et al., 2011, 2012, 2013), on the basis of televisive fiction, which culminated on concepts as transmediation and transmedia contents and deepened the comprehension and the research in this area. Thenceforth, this study propone a problematization and apropriation of this theoretic support for the journalism field, using, for that, a comprehension of journalistic production on a speech level, as well as its social practices (newsmaking). The empiric research also take two different paths. First, analyze a group of reportings, in which there is transmediation, in order to verifying the configuration of the transmedia phenomenom - more specifically of the transmedia storytelling - and its particularities to journalism. Then, develops an investigation, based on the etnographic method, of the productive routine on the special reporting section of the Jornal do Commercio (Recife/PE), aiming to investigate the conditions of transmediation in this range and the practices that favor and difficult the employment of transmedia storytelling. The result are, therefore, compared and related, with the goal of providing multidimensional view of the phenomenom

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

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O método de fluxo de carga convencional é considerado inadequado para se obter o ponto de máximo carregamento (PMC) de sistemas de potência, devido à singularidade da matriz Jacobiana neste ponto. Os métodos da continuação são ferramentas eficientes para a solução deste tipo de problema, visto que técnicas de parametrização podem ser utilizadas para evitar a singularidade da matriz Jacobiana. Neste trabalho, novas opções para a etapa de parametrização do método da continuação são apresentadas. Mostra-se que variáveis com claro significado físico podem ser utilizadas na etapa de parametrização. As seguintes variáveis foram testadas: perda total de potência ativa e reativa, potência ativa e reativa na barra de referência, potência reativa das barras de geração, e as perdas de potência ativa e reativa nas linhas de transmissão (LT). Além de facilitar a implementação computacional do método de continuação, as técnicas de parametrização apresentadas simplificam a definição matemática e o entendimento do método por parte de engenheiros de potência, visto que os métodos de continuação existentes na literatura sempre utilizam técnicas de parametrização complexas, e de interpretação puramente geométrica. Resultados obtidos com a nova metodologia para os sistemas testes do IEEE (14, 30, 57 e 118 barras) mostram que as características de convergência do método de fluxo de carga convencional são melhoradas na região do PMC. Além disso, durante o traçado das curvas PV, as diversas técnicas de parametrização podem ser comutadas entre si possibilitando o cálculo de todos os pontos da curva com um número reduzido de iterações. Diversos testes são realizados para proporcionar a comparação do desempenho dos esquemas de parametrização propostos.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

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Pós-graduação em Biofísica Molecular - IBILCE

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

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Pós-graduação em Matemática - IBILCE

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

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

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After two decades advertising and defending the synthetic method, João Köpke became active disseminator of analytical method for teaching reading. In five te xts published between 1896 and 1917, produced in different circumstance s for different publics readers, Köpke seeks the support of American and European authors, for their principles as well as for the education experience, to his analytical method. as by theirs principles as by theirs educational experiences. Among those authors: J. Jacotot, A. Bain, A. Meiklejohn, J. Froebel, C. Parker, G. Stanley Hall and J. Chubb. In this article, attention is given to repeated American references with special emphasis on the psychology of Stanley Hall and the method of teaching reading of Meiklejohn, highlighted and placed on convergence by Köpke in his final writings.

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