31,442 research outputs found

    Vulnerability assessment of the S. João de Loure Bridge: Vouga’s river

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    Steel bridges are particularly sensible to corrosion, which can put at risk the structural safety by affecting the joint elements. Having this in mind, the objective of this work was to evaluate the influence of the joint's stiffness in the structural response of the S. João de Loure steel bridge. An improved model was developed for the bridge on the structural analysis software SAP2000. Maximum deflection, axial forces and corresponding stresses, and natural frequencies, were analyzed. Numerical results allow concluding about the influence of the joint's stiffness in the structural response of the bridge

    S. João de Loure Bridge: vulnerability assessment and study of a common strengthening solution

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    This paper presents a structural vulnerability assessment of the steel bridge S. João de Loure. A structural model of the bridge was created and the influence of the joint’s stiffness on its structural response was evaluated using the structural analysis software SAP2000. Natural frequencies, axial forces and corresponding stress, and maximum mid-span deflection, were analyzed. A common strengthening solution with prestressing cables was studied intending to reduce the bridge’s mid-span deflection

    Integration once again: The Brazilian Northeast in the context of EU-Mercosul trade relations

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    Integration has meant great changes for Brazilian Northeast since its becoming part of the regional division of labour that allowed the constitution of a single domestic production system in the country in the 1950s. This process required the Northeastern economy to adjust to the extent of embarking into new industrial sectors and dismantling old industrial capacity, such as textiles. This adjustment has however developed the region's industrial capacity and competitiveness which allowed it to improve exports - both foreign and interregional - and reduce its so-called "structural" trade deficit in the 1980s. This context has changed by the constitution of the South American Common Market - the Mercosul. The new trade block has inspired northeastern polititians and diverse analysts to argue that the regional economy is to become less important for Brazilian domestic market and production system, as the interindustrial links are to enhance among southern and southeastern firms. Government expenditures as well as private investments concentrated in these regions gives them the explanation for their belief. The recent moves towards increasing the commercial links between the European Union and the Mercosul bring new facts to the context. The Northeast could emerge as holding competitive advantages out of this integration process into which the Brazilian economy is getting. There could be argued that the region's historical backwardness could decrease in the context of fusions, acquisitions and the like by European capital? Would not this be the case of moving backwards to the period in which there was no integrated domestic market and the Northeast, as other regions in Brazil, basically traded with European partners. These are the main questions this paper is to answer.

    Padrão de Atividade, Dieta e Uso do Espaço por Callicebus personatus (Primates, Pitheciidae) em uma Área de Parque Urbano, Município de Santa Teresa, ES.

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    A procura de alimento demanda tempo e gasto energético e o hábitat pode apresentar variações, fazendo com que os animais tomem Decisões sobre como se comportar nele. Estudos sobre comportamento e dieta de Callicebus personatus ainda são pontuais e com pouco tempo de dados de observação. Este estudo tem como objetivos apresentar como um grupo de C. personatus, que vive em um fragmento de mata inserido em uma área urbana, se comporta e avaliar se o consumo de frutos pelos guigós influencia os padrões de atividades e uso do espaço. O estudo foi conduzido durante os meses de setembro e novembro de 2011 e fevereiro a julho de 2012, utilizando a metodologia de amostragem instantânea. Os guigós passaram 50% do tempo descansando, 20% se movimentando, 17% se alimentando e 13% em interações sociais. Os frutos foram os alimentos mais utilizados pelos guigós, compreendendo cerca de 70% da dieta, incluindo, pelo menos, oito famílias botânicas. O orçamento temporal do grupo estudado seguiu o padrão encontrado em outros estudos de C. personatus. De acordo com as observações sobre as áreas utilizadas mensalmente, a área de parque arborizado, mais antropizada, é a área mais visitada. Lá estão concentradas as árvores exóticas, que estão frutificando (pelo menos uma espécie) ao longo de todo o ano. Os dados sugerem que os guigós utilizam a área de vida de acordo com a disponibilidade de recurso de frutos disponíveis, além de preferir ingerir itens de maior valor energético, como previsto pela Teoria de Forrageamento Ótimo

    Discrete Dynamical Systems: A Brief Survey

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    Dynamical system is a mathematical formalization for any fixed rule that is described in time dependent fashion. The time can be measured by either of the number systems - integers, real numbers, complex numbers. A discrete dynamical system is a dynamical system whose state evolves over a state space in discrete time steps according to a fixed rule. This brief survey paper is concerned with the part of the work done by José Sousa Ramos [2] and some of his research students. We present the general theory of discrete dynamical systems and present results from applications to geometry, graph theory and synchronization

    Theoretical prediction of interference loading on aircraft stores: Part I - Subsonic speeds

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    Computer program is developed for theoretically predicting loading on pylon-mounted stores in subsonic compressible flow. Linear theory predicts flow field produced by aircraft wing, nose, inlet, and pylons. Program was written in FORTRAN IV for CDC 6000 computer
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