994 resultados para Melissos, de Samos, s. V aC
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In this paper, a hybrid heuristic methodology that employs fuzzy logic for solving the AC transmission network expansion planning (AC-TEP) problem is presented. An enhanced constructive heuristic algorithm aimed at obtaining a significant quality solution for such complicated problems considering contingency is proposed. In order to indicate the severity of the contingency, 2 performance indices, namely the line flow performance index and voltage performance index, are calculated. An interior point method is applied as a nonlinear programming solver to handle such nonconvex optimization problems, while the objective function includes the costs of the new transmission lines as well as the real power losses. The performance of the proposed method is examined by applying it to the well-known Garver system for different cases. The simulation studies and result analysis demonstrate that the proposed method provides a promising way to find an optimal plan. Obtaining the best quality solution shows the capability and the viability of the proposed algorithm in AC-TEP. © Tübi̇tak..
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Pós-graduação em Biologia Geral e Aplicada - IBB
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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
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Vários estudos sobre o setor pesqueiro têm sido feitos na região amazônica, entretanto, a maior parte se concentra em regiões próximas à calha do rio do Amazonas e sua foz. Este trabalho foi voltado para caracterização da pesca no rio Purus, frota pesqueira comercial e do pescador em três municípios pesquisados nas margens desse rio, estimando, assim, a produção e a renda da frota pesqueira naquela região. Os resultados mostram que em Manoel Urbano (AC) predomina a pesca de lagos, enquanto que Sena Madureira (AC) os ambientes de pesca so mais diversificados, com registros de pesca em lagos, rios e igarapés. Em Boca do Acre (AM) prevalece a pesca no rio Purus, principalmente na área dos municípios de Pauiní e Lábrea. Quanto ao tipo de embarcação utilizada, em Manoel Urbano a pesca é praticada somente em canoas, sendo que um pequeno percentual corresponde a canoas sem motor, enquanto que em Sena Madureira a maioria dos pescadores pesca de canoas e alguns utilizam barco motor; já em Boca do Acre a pesca é praticada basicamente de barcos, sendo menor o número de canoas motorizadas. Em relação aos custos da viagem, a análise mostrou que os custos variáveis representam 63% da receita dos pescadores de canoa e 76% da receita total dos barcos de pesca. A análise também mostra que pescadores de canoa motorizada apresentaram maior capacidade produtiva por unidade de esforço em relação aos pescadores de barcos.
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The paper studies the mobilization occurred in June 2013 in Brazil, initially under the banner of the Movement Free Pass, but without the existence of a lead, but multiple voices that alternate in search of social and economic change. The object of study is the communication made through social networks and their realization, or realization, the streets of major cities. The rallies demonstrate the power of communications media and a new phenomenon of talk, the use of social networks, now as uniting factor and not just a showcase of everyday life. The internet has become a new means of communication easy and free access, in addition to its fast dissipation data. Thus, the youth was used such technology to an uprising in the pursuit of social improvement of the cities where marches happened. Such a move still without an academic and social needs to be discussed so that, in addition to understood, can expand contributions to society, helping it in its claims. Was chosen as the site for the #causabrasil study and understanding of issues in which the public expresses dissatisfaction. The site performs an analysis with the combination of hastags a list of pre-registered and a list of terms used by different users of Facebook, Twitter, Instagram, Youtube and Google, through monitoring tool Seekr, and an infographic presents the main political demands of the population.
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The paper studies the mobilization occurred in June 2013 in Brazil, initially under the banner of the Movement Free Pass, but without the existence of a lead, but multiple voices that alternate in search of social and economic change. The object of study is the communication made through social networks and their realization, or realization, the streets of major cities. The rallies demonstrate the power of communications media and a new phenomenon of talk, the use of social networks, now as uniting factor and not just a showcase of everyday life. The internet has become a new means of communication easy and free access, in addition to its fast dissipation data. Thus, the youth was used such technology to an uprising in the pursuit of social improvement of the cities where marches happened. Such a move still without an academic and social needs to be discussed so that, in addition to understood, can expand contributions to society, helping it in its claims. Was chosen as the site for the #causabrasil study and understanding of issues in which the public expresses dissatisfaction. The site performs an analysis with the combination of hastags a list of pre-registered and a list of terms used by different users of Facebook, Twitter, Instagram, Youtube and Google, through monitoring tool Seekr, and an infographic presents the main political demands of the population.
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The preserved activity of immobilized biomolecules in layer-by-layer (LbL) films can be exploited in various applications. including biosensing. In this study, cholesterol oxidase (COX) layers were alternated with layers of poly(allylamine hydrochloride) (PAH) in LbL films whose morphology was investigated with atomic force microscopy (AFM). The adsorption kinetics of COX layers comprised two regimes, a fast, first-order kinetics process followed by a slow process fitted with a Johnson-Mehl-Avrami (JMA) function. with exponent similar to 2 characteristic of aggregates growing as disks. The concept based on the use of sensor arrays to increase sensitivity, widely employed in electronic tongues, was extended to biosensing with impedance spectroscopy measurements. Using three sensing units, made of LbL films of PAH/COX and PAHIPVS (polyvinyl sulfonic acid) and a bare gold interdigitated electrode, we were able to detect cholesterol in aqueous solutions down to the 10(-6) M level. This high sensitivity is attributed to the molecular-recognition interaction between COX and cholesterol, and opens the way for clinical tests to be made with low cost. fast experimental procedures. (C) 2008 Published by Elsevier B.V.
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High pressure NMR spectroscopy has developed into an important tool for studying conformational equilibria of proteins in solution. We have studied the amide proton and nitrogen chemical shifts of the 20 canonical amino acids X in the random-coil model peptide Ac-Gly-Gly-X-Ala-NH2, in a pressure range from 0.1 to 200 MPa, at a proton resonance frequency of 800 MHz. The obtained data allowed the determination of first and second order pressure coefficients with high accuracy at 283 K and pH 6.7. The mean first and second order pressure coefficients <B-1(15N)> and <B-2(15N)> for nitrogen are 2.91 ppm/GPa and -2.32 ppm/GPa(2), respectively. The corresponding values <B-1(1H)> and <B-2(1H)> for the amide protons are 0.52 ppm/GPa and -0.41 ppm/GPa(2). Residual dependent (1)J(1H15N)-coupling constants are shown.