997 resultados para painel MDF
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Com o objetivo de preservar e disseminar o acervo da Universidade de São Paulo, foi criada a Biblioteca de Obras Raras e Especiais. Contamos atualmente com cerca de 2500 obras digitalizadas em parceria com a Brasiliana USP e apoio da FAPESP. Estas obras estão disponibilizadas online, para consulta aberta pelo amplo público, promovendo assim acesso ao conhecimento. Utilizamos para isto o Corisco, uma plataforma desenvolvida por pesquisadores da Brasiliana USP baseada em DSpace, software de código aberto e com recursos que promovem a interoperabilidade com outras bases. O DSpace é atualmente o aplicativo de Repositório Digital de código aberto mais utilizado nas Universidades ao redor do mundo. As capturas originais em alta resolução das obras são armazenadas e indexadas para fins de preservação. Em outra frente, realiza-se o tratamento, compactação e reconhecimento ótico de caracteres nas imagens, para que então as obras possam ser disponibilizadas na internet com o recurso de busca no conteúdo. A consulta é livre e gratuita, garantindo assim, além da preservação, o acesso ao conhecimento pela comunidade acadêmica e público em geral.
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Com o objetivo de preservar e disseminar o acervo da Universidade de São Paulo, foi disponibilizada a Biblioteca Digital de Obras Raras e Especiais, com apoio da FAPESP, utilizando a plataforma Corisco, desenvolvida por pesquisadores da Brasiliana USP, baseada em softwares de código aberto com recursos que permitem a interoperabilidade com outros bancos de dados. A Plataforma Corisco é um produto desenvolvido pela Brasiliana USP, consistindo de um sistema integrado de aplicativos de código aberto e recomendações para sustentar a implantação e gerenciamento de repositórios digitais de acordo com padrões de interoperabilidade. A Plataforma Corisco roda sobre o DSpace, um dos aplicativos de Repositório Digital de código aberto mais utilizados nas Universidades ao redor do mundo. As obras, em domínio público, são digitalizadas e suas imagens tratadas, para então serem disponibilizadas. E graças ao reconhecimento ótico de caracteres é possível realizar a busca no conteúdo, potencializando resultados. A consulta é livre e gratuita, garantindo assim, além da preservação, o acesso ao conhecimento pela comunidade acadêmica e público em geral.
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RATIONALE: The interaction between lungs and chest wall influences lung volume, that determines lung history during respiration cycle. In this study, the influence of chest wall mechanics on respiratory system is assessed by the evaluation of inspiration pressure-volume curve (PV curve) under three different situations: closed-chest, open-chest and isolated lung. The PV curve parameters in each situation allow us to further understand the role played by different chest wall elements in the respiratory function. Methods: Twenty-four male Wistar rats (236 ± 29 g) were used. The animals were weighted and then anesthetized with xylazine 2% (O,SmL/kg) and ketamine 10% (0,9mL/kg), exsanguinated and later tracheostomies with a metallic cannula (14 gauge).The cannula was connected to an automatic small animal insufflator. This setup was connected to a pressure transducer (32 samples/s). The 24 animals were randomly separated in three groups:(i) closed chest,(ii) open chest and (iii) isolated lung. The rats were insufflated with 20mL quasi-statically (constant speed of 0,1mUs). lnsufflated volume and measured pressure data were kept and PV curves were obtained for all animals. The PV curves were fitted (non-linear least squares) against the sigmoid equation (1) to obtain the sigmoid equation parameters (a,b,c,d). Elastance measurements were obtained from linear regression of pressure/volume measurements in a 0,8s interval before and after the calculated point. Results: The parameters a,b and c showed no significant change, but the parameter d showed a significant variation among the three groups. The initial elastance also varied between open and closed chest, indicating the need of a higher pressure for the lung expansion, as can be seen in Table 1. Conclusion: A supporting effect of the chest wall was observed at the initial moments of inspiration, observed as a higher initial elastance in open chest situations than in closed chest situations (p=0,00001). The similar initial elastance for the isolated lung and closed chest may be explained by the specific method used for the isolated lung experiment. As the isolated lung is supported by the trachea vertically, the weight of the tissue may have a similar effect of the residual negative pressure in the thorax, responsible for maintaining the residual volume.
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The importance of mechanical aspects related to cell activity and its environment is becoming more evident due to their influence in stem cell differentiation and in the development of diseases such as atherosclerosis. The mechanical tension homeostasis is related to normal tissue behavior and its lack may be related to the formation of cancer, which shows a higher mechanical tension. Due to the complexity of cellular activity, the application of simplified models may elucidate which factors are really essential and which have a marginal effect. The development of a systematic method to reconstruct the elements involved in the perception of mechanical aspects by the cell may accelerate substantially the validation of these models. This work proposes the development of a routine capable of reconstructing the topology of focal adhesions and the actomyosin portion of the cytoskeleton from the displacement field generated by the cell on a flexible substrate. Another way to think of this problem is to develop an algorithm to reconstruct the forces applied by the cell from the measurements of the substrate displacement, which would be characterized as an inverse problem. For these kind of problems, the Topology Optimization Method (TOM) is suitable to find a solution. TOM is consisted of an iterative application of an optimization method and an analysis method to obtain an optimal distribution of material in a fixed domain. One way to experimentally obtain the substrate displacement is through Traction Force Microscopy (TFM), which also provides the forces applied by the cell. Along with systematically generating the distributions of focal adhesion and actin-myosin for the validation of simplified models, the algorithm also represents a complementary and more phenomenological approach to TFM. As a first approximation, actin fibers and flexible substrate are represented through two-dimensional linear Finite Element Method. Actin contraction is modeled as an initial stress of the FEM elements. Focal adhesions connecting actin and substrate are represented by springs. The algorithm was applied to data obtained from experiments regarding cytoskeletal prestress and micropatterning, comparing the numerical results to the experimental ones
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The pulmonary crackling and the formation of liquid bridges are problems that for centuries have been attracting the attention of scientists. In order to study these phenomena, it was developed a canonical cubic lattice-gas like model to explain the rupture of liquid bridges in lung airways [A. Alencar et al., 2006, PRE]. Here, we further develop this model and add entropy analysis to study thermodynamic properties, such as free energy and force. The simulations were performed using the Monte Carlo method with Metropolis algorithm. The exchange between gas and liquid particles were performed randomly according to the Kawasaki dynamics and weighted by the Boltzmann factor. Each particle, which can be solid (s), liquid (l) or gas (g), has 26 neighbors: 6 + 12 + 8, with distances 1, √2 and √3, respectively. The energy of a lattice's site m is calculated by the following expression: Em = ∑k=126 Ji(m)j(k) in witch (i, j) = g, l or s. Specifically, it was studied the surface free energy of the liquid bridge, trapped between two planes, when its height is changed. For that, was considered two methods. First, just the internal energy was calculated. Then was considered the entropy. It was fond no difference in the surface free energy between this two methods. We calculate the liquid bridge force between the two planes using the numerical surface free energy. This force is strong for small height, and decreases as the distance between the two planes, height, is increased. The liquid-gas system was also characterized studying the variation of internal energy and heat capacity with the temperature. For that, was performed simulation with the same proportion of liquid and gas particle, but different lattice size. The scale of the liquid-gas system was also studied, for low temperature, using different values to the interaction Jij.
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In this work, we reported some results about the stochastic quantization of the spherical model. We started by reviewing some basic aspects of this method with emphasis in the connection between the Langevin equation and the supersymmetric quantum mechanics, aiming at the application of the corresponding connection to the spherical model. An intuitive idea is that when applied to the spherical model this gives rise to a supersymmetric version that is identified with one studied in Phys. Rev. E 85, 061109, (2012). Before investigating in detail this aspect, we studied the stochastic quantization of the mean spherical model that is simpler to implement than the one with the strict constraint. We also highlight some points concerning more traditional methods discussed in the literature like canonical and path integral quantization. To produce a supersymmetric version, grounded in the Nicolai map, we investigated the stochastic quantization of the strict spherical model. We showed in fact that the result of this process is an off-shell supersymmetric extension of the quantum spherical model (with the precise supersymmetric constraint structure). That analysis establishes a connection between the classical model and its supersymmetric quantum counterpart. The supersymmetric version in this way constructed is a more natural one and gives further support and motivations to investigate similar connections in other models of the literature.
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A Universidade de São Paulo, Brasil congrega 5.732 docentes, mais de 80 mil alunos de graduação e pós-graduação e tem seu sistema de informação composto por 44 bibliotecas distribuídas em sete campina capital e nove em cidades do interior do estado de São Paulo. Sua produção intelectual anual (técnico-científica, artística e didática) é superior a 40 mil itens. Desenvolver estratégias de política de acesso aberto neste contexto, tem sido uma atividade continua desde 2002. Iniciou-se com a implantação da Biblioteca Digital de Teses e Dissertações, seguiu-se o Portal de Revistas Científicas. Atualmente, iniciou-se a construção do Repositório Institucional da Produção Científica, abarcando publicações de artigos, livros, capítulos de livros, trabalhos em eventos etc. Neste momento, buscando refletir sobre acesso a publicações que envolvem a participação de terceiros e que influenciam a estrutura de avaliação da ciência regulamentada por organismos governamentais, novas estratégias se mostraram necessárias. Optou-se então pela composição de grupo multiplicador composto de professores e alunos, criação de espaço de referência cobrindo temas distintos sobre o acesso aberto, workshop, fórum aberto para discussão do acesso aberto na USP e elaboração de carta de intenções em fase de assinatura e endosso pela comunidade uspiana.
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Introdução: A Faculdade de Saúde Pública, assim como a Universidade de São Paulo, tem, na sua produção intelectual, literatura científica de relevância para a área da saúde, que sempre está a frente no desenvolvimento de tecnologia e na organização da informação. É importante que essa produção esteja acessível à sua comunidade, técnicos e profissionais da saúde, além da população em geral. A Biblioteca da FSP/USP, por ser uma das curadoras desse conhecimento, constitui-se, além de memória bibliográfica institucional de importância para a história da saúde pública brasileira, em uma fonte de informação valiosa, cujo acesso deve ser garantido. Objetivo: Apresentar o desenvolvimento de um repositório digital em uma biblioteca acadêmica. Métodos: A oportunidade da criação do repositório surgiu como parte de um projeto de infraestrutura de pesquisa da Fundação de Amparo à Pesquisa do Estado de São Paulo. Na sua concepção foi previsto o uso da plataforma DSpace e o padrão de metadados Dublin Core, com adaptações. para sua implantação foram adquiridos: dois servidores e respectivos no-breaks, um “storage” com capacidade de 8 terabytes e dois escâneres com design especial para acomodação de lombadas. Uma equipe de informática responsabilizou-se pela instalação e configuração dos softwares, e a de marketing desenvolveu o design gráfico. Resultado e discussão: O repositório dispõe de cerca de 600 registros, com os devidos níveis de possibilidade de acesso – aberto, restrito ou embargado –, em fase de inauguração (prevista para 2012). A equipe do projeto é formada por profissionais com experiência e conhecimento em diversas áreas: metadados, preservação digital, usabilidade, design gráfico, marketing, direitos autorais, arquivamento de dados, backups, sistemas de autenticação e firewalls, entre outros. Parte da digitalização dos documentos foi executada por empresa especializada, que também treinou a equipe da Biblioteca, tendo sido digitalizadas, até o momento, 205.000 páginas. A Biblioteca instalou uma Oficina de Digitalização para dar continuidade ao repositório, que é atrelado à área de Desenvolvimento de Coleções. Além da produção intelectual da Faculdade, esse repositório conterá documentos da história do Estado de São Paulo e a do Brasil, no que se refere à informação científica em saúde publica. Entre sua concepção e implantação foram dois anos de trabalho da equipe da Biblioteca. Conclusões e comentários: O Repositório Digital da Biblioteca da FSP/USP foi desafiante desde sua concepção até o financiamento, capacitação e manutenção de equipes, entre eles a customização do DSpace. Da mesma forma, foi uma oportunidade para a equipe ampliar seu “know-how”. Os impactos positivos de um projeto desse porte incidem sobre o acesso ao conhecimento muito mais facilitado, de forma gratuita e universal, agregando maior valor aos registros das bases bibliográficas à medida que disponibiliza links para os textos completos, áudios, vídeos e imagens, para a divulgação da ciência.
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A sociedade atual exige inovadores ambientes de trabalho para lidar efetivamente com uma carga cada vez maior de informações heterogêneas. A produção e divulgação dos dados e novos conhecimentos também ocorrem de forma rápida e ampla. No entanto, recuperar informação relevante torna-se cada vez mais difícil, uma vez que o conhecimento humano não está mais centralizado em unidades físicas de informação e sim distribuído, inclusive em repositórios digitais. Com a diversidade de suportes existentes uma informação pode estar num livro, num artigo, num filme ou num arquivo de áudio. O objetivo deste trabalho é definir os metadados para registros de áudio em repositórios digitais de acesso aberto, garantindo que essas informações tenham maior visibilidade no extenso universo da internet. Os metadados possuem importante contribuição no registro e na futura recuperação do recurso informacional, tornando acessíveis coleções que existem apenas em formato digital. Assim, o processo de recuperação depende da qualidade do tratamento dado ao documento e da escolha e uso dos tipos de metadados. O Dublin Core (DC) é um dos esquemas de metadados mais utilizado em repositórios digitais, sendo já um padrão ISO (ISO 15836:2009). Neste trabalho foi feita a identificação e comparação dos metadados disponíveis no formato MARC 21, na metodologia LILACS e também no esquema DC, definindo-se um escopo mínimo de metadados. Para melhorar e completar a descrição dos registros desse tipo de material, que possui uma complexidade específica, também foram acrescentados novos metadados com base em estudos feitos pela Library of Congress para o desenvolvimento de sua coleção digital. O resultado do trabalho é um formulário específico para os materiais de coleções de áudio, mantendo a compatibilidade e interoperabilidade com o esquema Dublin Core. Aos elementos existentes foram agregados refinamentos como entrevistador, editor de som, áudio bits, duração e identificação do arquivo, que abrangem e melhoram os aspectos de descrição e preservação digital. O mundo está rapidamente sendo transformado pela proliferação de recursos de informação disponíveis e distribuídos pela rede de computadores com um número cada vez maior de instituições que têm desenvolvido coleções digitais. Uma das vantagens das coleções em áudio é o fato de que a linguagem utilizada na expressão oral, especialmente em entrevistas, tende a ser mais coloquial e por isso torna a informação mais acessível aos ouvintes não especializados nas disciplinas em questão e faz a ponte entre universidade e sociedade. Dar visibilidade às coleções de áudio, “spots” de rádio acessíveis que podem ser veiculados por rádios comunitárias e educativas, vai ao encontro do papel de promoção de pesquisas das instituições. Esse compartilhamento da informação contribui para a construção da cidadania e capacitação da população para participar das políticas públicas
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USP scientific production. USP journals. USP Open Access Movement.
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USP INFORMATION MANDATE – Resolution 6444 – Oct. 22th, 2012 Make public and accessible the knowledge generated by research developed at USP, encouraging the sharing, the use and generation of new content; •Preserve institutional memory by storing the full text of Intellectual Production (scientific, academic, artistic and technical); •Increase the impact of the knowledge generated in the university within the scientific community and the general public; •It is suggested to all members of the USP community to publish the results of their research, preferably, in open-access publication outlets and/or repositories and to include the permission to deposit their production in the BDPI system in their publication agreements. •Institutional Repository for Intellectual Production; •Official Source USP Statistical Yearbook.
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CHAPTER 1:FLUID-VISCOUS DAMPERS In this chapter the fluid-viscous dampers are introduced. The first section is focused on the technical characteristics of these devices, their mechanical behavior and the latest evolution of the technology whose they are equipped. In the second section we report the definitions and the guide lines about the design of these devices included in some international codes. In the third section the results of some experimental tests carried out by some authors on the response of these devices to external forces are discussed. On this purpose we report some technical schedules that are usually enclosed to the devices now available on the international market. In the third section we show also some analytic models proposed by various authors, which are able to describe efficiently the physical behavior of the fluid-viscous dampers. In the last section we propose some cases of application of these devices on existing structures and on new-construction structures. We show also some cases in which these devices have been revealed good for aims that lies outside the reduction of seismic actions on the structures. CHAPTER 2:DESIGN METHODS PROPOSED IN LITERATURE In this chapter the more widespread design methods proposed in literature for structures equipped by fluid-viscous dampers are introduced. In the first part the response of sdf systems in the case of harmonic external force is studied, in the last part the response in the case of random external force is discussed. In the first section the equations of motion in the case of an elastic-linear sdf system equipped with a non-linear fluid-viscous damper undergoing a harmonic force are introduced. This differential problem is analytically quite complex and it’s not possible to be solved in a closed form. Therefore some authors have proposed approximate solution methods. The more widespread methods are based on equivalence principles between a non-linear device and an equivalent linear one. Operating in this way it is possible to define an equivalent damping ratio and the problem becomes linear; the solution of the equivalent problem is well-known. In the following section two techniques of linearization, proposed by some authors in literature, are described: the first technique is based on the equivalence of the energy dissipated by the two devices and the second one is based on the equivalence of power consumption. After that we compare these two techniques by studying the response of a sdf system undergoing a harmonic force. By introducing the equivalent damping ratio we can write the equation of motion of the non-linear differential problem in an implicit form, by dividing, as usual, for the mass of the system. In this way, we get a reduction of the number of variables, by introducing the natural frequency of the system. The equation of motion written in this form has two important properties: the response is linear dependent on the amplitude of the external force and the response is dependent on the ratio of the frequency of the external harmonic force and the natural frequency of the system only, and not on their single values. All these considerations, in the last section, are extended to the case of a random external force. CHAPTER 3: DESIGN METHOD PROPOSED In this chapter the theoretical basis of the design method proposed are introduced. The need to propose a new design method for structures equipped with fluid-viscous dampers arises from the observation that the methods reported in literature are always iterative, because the response affects some parameters included in the equation of motion (such as the equivalent damping ratio). In the first section the dimensionless parameterε is introduced. This parameter has been obtained from the definition of equivalent damping ratio. The implicit form of the equation of motion is written by introducing the parameter ε, instead of the equivalent damping ratio. This new implicit equation of motions has not any terms affected by the response, so that once ε is known the response can be evaluated directly. In the second section it is discussed how the parameter ε affects some characteristics of the response: drift, velocity and base shear. All the results described till this point have been obtained by keeping the non-linearity of the behavior of the dampers. In order to get a linear formulation of the problem, that is possible to solve by using the well-known methods of the dynamics of structures, as we did before for the iterative methods by introducing the equivalent damping ratio, it is shown how the equivalent damping ratio can be evaluated from knowing the value of ε. Operating in this way, once the parameter ε is known, it is quite easy to estimate the equivalent damping ratio and to proceed with a classic linear analysis. In the last section it is shown how the parameter ε could be taken as reference for the evaluation of the convenience of using non-linear dampers instead of linear ones on the basis of the type of external force and the characteristics of the system. CHAPTER 4: MULTI-DEGREE OF FREEDOM SYSTEMS In this chapter the design methods of a elastic-linear mdf system equipped with non-linear fluidviscous dampers are introduced. It has already been shown that, in the sdf systems, the response of the structure can be evaluated through the estimation of the equivalent damping ratio (ξsd) assuming the behavior of the structure elastic-linear. We would to mention that some adjusting coefficients, to be applied to the equivalent damping ratio in order to consider the actual behavior of the structure (that is non-linear), have already been proposed in literature; such coefficients are usually expressed in terms of ductility, but their treatment is over the aims of this thesis and we does not go into further. The method usually proposed in literature is based on energy equivalence: even though this procedure has solid theoretical basis, it must necessary include some iterative process, because the expression of the equivalent damping ratio contains a term of the response. This procedure has been introduced primarily by Ramirez, Constantinou et al. in 2000. This procedure is reported in the first section and it is defined “Iterative Method”. Following the guide lines about sdf systems reported in the previous chapters, it is introduced a procedure for the assessment of the parameter ε in the case of mdf systems. Operating in this way the evaluation of the equivalent damping ratio (ξsd) can be done directly without implementing iterative processes. This procedure is defined “Direct Method” and it is reported in the second section. In the third section the two methods are analyzed by studying 4 cases of two moment-resisting steel frames undergoing real accelerogramms: the response of the system calculated by using the two methods is compared with the numerical response obtained from the software called SAP2000-NL, CSI product. In the last section a procedure to create spectra of the equivalent damping ratio, affected by the parameter ε and the natural period of the system for a fixed value of exponent α, starting from the elasticresponse spectra provided by any international code, is introduced.
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Most quark actions in lattice QCD encounter difficulties with chiral sym-rnmetry and its spontaneous breakdown. Minimally doubled fermions (MDF)rnare a category of strictly local chiral lattice fermions, whose continuum limitrnreproduces two degenerate quark flavours. The two poles of their Dirac ope-rnrator are aligned such that symmetries under charge conjugation or reflectionrnof one particular direction are explictly broken at finite lattice spacing. Pro-rnperties of MDF are scrutinised with regard to broken symmetry and mesonrnspectrum to discern their suitability for numerical studies of QCD.rnrnInteractions induce anisotropic operator mixing for MDF. Hence, resto-rnration of broken symmetries in the continuum limit requires three coun-rnterterms, one of which is power-law divergent. Counterterms and operatorrnmixing are studied perturbatively for two variants of MDF. Two indepen-rndent non-perturbative procedures for removal of the power-law divergencernare developed by means of a numerical study of hadronic observables forrnone variant of MDF in quenched approximation. Though three out of fourrnpseudoscalar mesons are affected by lattice artefacts, the spectrum’s conti-rnnuum limit is consistent with two-flavour QCD. Thus, suitability of MDF forrnnumerical studies of QCD in the quenched approximation is demonstrated.