Dissertação (mestrado)—Universidade de Brasília, Departamento de Teoria literária e literturas, 2010. / Submitted by wiliam de oliveira aguiar (wiliam@bce.unb.br) on 2011-06-20T16:57:34Z No. of bitstreams: 1 2010_MaríliaMachadoGarciadeLima.pdf: 973249 bytes, checksum: e8eb4ce3302160be069c4e9537501101 (MD5) / Approved for entry into archive by Guilherme Lourenço Machado(gui.admin@gmail.com) on 2011-06-21T12:47:56Z (GMT) No. of bitstreams: 1 2010_MaríliaMachadoGarciadeLima.pdf: 973249 bytes, checksum: e8eb4ce3302160be069c4e9537501101 (MD5) / Made available in DSpace on 2011-06-21T12:47:56Z (GMT). No. of bitstreams: 1 2010_MaríliaMachadoGarciadeLima.pdf: 973249 bytes, checksum: e8eb4ce3302160be069c4e9537501101 (MD5) / A representação do indígena tem uma tradição já consolidada na literatura brasileira. O procedimento literário utilizado para essa representação é chamado de transfiguração. A transfiguração do indígena é explicada por Antonio Candido (1918-) como dentro do contexto da literatura romântica brasileira do século XIX, mas, que, posteriormente, tornase uma tradição, com suas semelhanças e diferenças. Um dos maiores escritores do Romantismo literário brasileiro é José de Alencar (1829-1877), e parte de sua obra é dedicada à temática indígena. Portanto, é analisada a obra Iracema (1865) dentro do contexto de transfiguração sugerido por Candido. Outra grande obra da Literatura Brasileira sobre a temática indígena é Maíra (1976), de Darcy Ribeiro (1922-1997), em que também ocorre transfiguração, demonstrando, assim, uma tradição consolidada do sistema literário brasileiro. Porém, uma transfiguração diferente da que acontece em Iracema. Maíra se aproxima do contexto literário que Candido chama de super-regionalismo, ou seja, uma superação do regionalismo, que, com relação à transfiguração do indígena, constitui-se como uma explosão conceitual do que era a figuração do indígena no Romantismo brasileiro e questiona o papel atribuído ao índio pela literatura de justificar ideologicamente a invenção de um passado glorioso para o país. Temos, então, em Maíra, uma Iracema negativa e questionadora da colonização. Portanto, partimos de uma “consciência amena do atraso”, termo esse também definido por Candido, em Iracema, na época da Independência brasileira, em que se tinha como objetivo a formação da nação, e chegamos a uma “consciência catastrófica do atraso”, em Maíra, em que há consciência dos problemas estruturais brasileiros. _______________________________________________________________________________ ABSTRACT / The representation of the Indian has a tradition already consolidated in Brazilian Literature. The literary procedure used for this representation is called transfiguration. The transfiguration of the Indian is explained by Antônio Cândido (1918) as within the context of Brazilian romantic literature of the XIX century, but, that, later becomes a tradition, with their similarities and differences. One of the greatest Brazilian authors of literary romanticism is José de Alencar (1829-1877), who dedicated part of his literary compositions to indigenous themes. Therefore, the literary composition Iracema (1865) is thus analysed within the context suggested by Cândido. Another great literary composition of Brazilian literature about indigenous themes is Maíra (1976) by Darcy Ribeiro (1922- 1977), in which transfiguration also occurs, thus showing a consolidated tradition of the Brazilian literary system. Howevekr, different to the transfiguration which takes place in Iracema, Maíra is within a context that Cândido calls super-regionalism, or, the overcoming of regionalism. A conceptual explosion of what was the Indian figuration in Brazilian romanticism for an Indian that no longer has the role of ideological justification of a once glorious past. So we find in Maíra an Iracema that is not only negative but questions colonization. Thus, we move from a “light conscience of delay”, a term which was also defined by Cândido in Iracema, after the Brazilian independence, a time during which the aim was to form the State-nation, to a “catastrophic conscience of delay” in Maíra, in which there is a consciousness of the Brazilian structural problems.

Orientador: Guilhermo Raul Ruben / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Filosofia e Ciencias Humanas / Made available in DSpace on 2018-08-08T09:50:06Z (GMT). No. of bitstreams: 1 Mattos_AndreLuisLopesBorgesde_D.pdf: 2090782 bytes, checksum: f21af214ed723ef857839cff06361a2d (MD5) Previous issue date: 2007 / Resumo: Esta tese analisa a trajetória de Darcy Ribeiro entre os anos de 1944 e 1982, período que corresponde à sua atuação, primeiro como antropólogo, depois como político e exilado, e durante o qual foi elaborada a quase totalidade de sua obra antropológica. Personagem dos mais importantes na consolidação da antropologia brasileira dos anos 50 e autor de livros de repercussão internacional, sua trajetória tornou-se, no entanto, particularmente a partir da segunda metade da década de 70, de certa forma deslocada em relação a boa parte do trabalho realizado por antropólogos no país, o que acabou por minimizar sua influência intelectual no cenário antropológico brasileiro. Isto se explica não só por Darcy ter valorizado uma intensa participação política junto ao Estado, iniciada ainda na década de 60, como também por ter sido o autor de uma antropologia fortemente marcada por uma experiência específica vivenciada por ele, como exilado, em diversos países da América Latina. Desta forma, ao acompanhar o seu percurso, busco entender como se articulam o discurso, a prática e a obra de Darcy Ribeiro no período em questão, a partir de um campo empírico específico. Refiro-me ao acervo pessoal de Darcy Ribeiro, atualmente sob os auspícios da Fundação Darcy Ribeiro, cuja documentação, praticamente inexplorada no campo das ciências sociais, constitui a fonte da maior parte das discussões realizadas no presente trabalho / Abstract: This thesis analyzes the path made by Darcy Ribeiro from 1944 to 1982, period of time which corresponds to his activity, first of all as an anthropologist, and then as a politician and as a refugee. And it was mostly during this period that almost all of his anthropological work was written. He was one of the most important characters in the consolidation of the Brazilian anthropology from the 50â?¿s and he was the author of books with international importance. His path was, nevertheless, different, in a certain way, from the work done by other anthropologists in the country, especially after the middle of 70â?¿s. With this attitude, his intellectual influence in the Brazilian anthropological group was minimized. We can understand that by the fact that Darcy had an intense political participation in the government, starting in the beginning of the 60â?¿s and also by being an author of an anthropology designed by his experience as a refugee in many Latin America countries. So, by following his path, I try to understand how his speech, his practice and his work were articulated during these years. This research is based on a specific field research. Iâ?¿m talking about Darcy Ribeiroâ?¿s personal archive, nowadays supervised by the Darcy Ribeiroâ?¿s Foundation. These documents, which are practically unexplored in the social sciences studies, are the major source of all the discussions done in this work / Doutorado / Ciencias Sociais / Doutor em Ciências Sociais

O microtubo é um emissor simples, de baixo custo, com a grande vantagem de melhor adaptação em condições de topografias onduladas e montanhosas, onde a pressão na linha lateral varia consideravelmente. Este estudo constitui a elaboração de um modelo para dimensionamento hidráulico de microaspersores, cujo emissor é um microtubo de tamanho variável. O fundamento teórico do estudo baseia-se na premissa da compensação da perda de carga na linha lateral e das diferenças topográficas do terreno, através da variação do comprimento do microtubo. Os objetivos específicos deste trabalho foram: determinar as características hidráulicas do microtubo; desenvolver um modelo para dimensionamento do sistema de irrigação proposto e sugerir um defletor para o microaspersor; avaliar a uniformidade de vazão ao longo de linhas laterais experimentais em declive e desenvolver uma planilha eletrônica, para dimensionamento de microtubos. Dois microtubos de diferentes diâmetros foram utilizados neste estudo. Entre as características hidráulicas determinadas, estão o diâmetro interno real, relação vazão-pressão e pressão-comprimento. A determinação do diâmetro interno médio dos microtubos foi realizada em laboratório através da medida de fluxo sob regime laminar e pelo projetor ótico de perfil. Uma equação resultante da combinação das equações de energia desenvolvida por Bernoulli e Darcy-Weisbach além da equação de Hagen-Poiseuille para cálculo do fator de atrito (f), foi deduzida para cálculo do diâmetro. Uma bancada de ensaios foi montada para realização dos ensaios. Os experimentos foram realizados numa faixa de número de Reynolds entre 8000 e 17000, portanto regime de escoamento turbulento. A equação de Darcy-Weisbach foi utilizada para cálculo da perda de carga total e a equação de Blasius foi utilizada para cálculo do fator de atrito (f). Duas laterais foram dimensionadas e instaladas em diferentes declividades (0,5 e 2,3 %). Medidas de dispersão foram utilizadas para avaliar e classificar o sistema de irrigação. Dois modelos de defletores foram desenvolvidos em laboratório, e avaliados em termos de distribuição espacial da água e facilidade construtiva. A análise dos resultados experimentais foi realizada em bases empíricas e teóricas. A avaliação hidrodinâmica do diâmetro dos microtubos aproximou-se muito da determinação através do projetor ótico de perfil, o que indica ser uma alternativa viável para o dimensionamento. A estimativa da pressão de operação do microaspersor baseada nas equações propostas foi bem próxima à pressão observada. O modelo empírico estimou o comprimento do microtubo em função da pressão com bastante precisão, consequentemente a uniformidade de vazão ao longo da lateral foi classificada como excelente em ambas as situações de declive, com coeficientes superiores a 95 %. Uma análise de sensibilidade para estimar as implicações no desempenho hidráulico do sistema, dos erros ou das mudanças nas variáveis envolvidas no dimensionamento, mostrou que o desempenho do emissor é extremamente sensível ao diâmetro do microtubo. Baseado nos resultados obtidos com os ensaios de distribuição pode-se afirmar que é necessário um maior aprofundamento no projeto do defletor do microaspersor. Em geral, a metodologia proposta oferece a possibilidade de ajustar quaisquer variações na carga de pressão ou na topografia do terreno e assim, obter vazão constante ao longo da linha lateral. / The microtube is a simple and cheap emitter which has advantage of be suitable for undulating and hilly conditions, where pressure in the lateral line varies considerably. This study aims to develop an empirical approach to the design of a novel micro-sprinkler that uses microtube as the emitters whose length is variable. The theoretic concern is the irrigation system should be designed to compensate variations along lateral line as a function of the friction loss and elevation. General objectives were: hydraulic characterization of the microtube; empiric equations to design; to develop a kind of deflector; to evaluate application uniformity for micro-sprinkler and to do a worksheet to design this system. The relationship between discharge, pressure, and length for microtube emitters of two different diameters were done. The diameter was measured based on flow measurements under laminar flow condition and by accurate optical equipment. Combination of the energy (Bernoulli) and Darcy-Weisbach equations and Hagen-Poiseuille equation (friction factor laminar flow) gives the diameter. A test table to do tests was built. The range of Reynolds numbers during the experiment was 8,000 to 17,000, then turbulent flow. The friction head losses were calculated using the Darcy-Weisbach equation and the friction factor by Blasius equation. Two experimental lines were designed and laid on different slopes (0.5 % and 2.3 %). To evaluate the uniformity of application of water, dispersion measures are used. Two deflectors were created and tested in the laboratory by spatial distribution analysis and easily to manufacture. The data was analyzed by theoretical and empirical approaches. The diameter values of the microtubes were very close to those by optical equipment, then it is a good alternative method to determinate the diameter of the microtube. The pressure observed values were very close to estimated. The empirical approach determined the length required for the microtube emitters with high accuracy, consequently the flow rate uniformity along lateral line was excellent for both laterals, their uniformity coefficients were above 95%. A sensitivity analysis to estimate the implications of errors or changes in key variables on the hydraulic performance of this system showed that the emitter performance is particularly sensitive to the emitter diameter. The deflector tests results showed low spatial uniformity, so we can say that it is necessary more studies at this part of this micro-sprinkler. Finally, the methodology proposed allow adjust any head pressure or elevation variations to high uniformity along of lateral line.

As plantações florestais, historicamente, estão associada a intensos debates sobre o seu impacto na dinâmica da água do solo ou subterrânea. Nesse contexto, este trabalho buscou avaliar os possíveis impactos da mudança de cobertura do solo, de pastagem para eucalipto, sobre o aquífero freático em zona de afloramento do Sistema Aquífero Guarani. A área de pesquisa está localizada na bacia do Ribeirão da Onça, situada no município de Brotas, no centro-leste do Estado de São Paulo. Essa é monitorada desde 2004. Foram utilizados dois métodos para avaliar o impacto da mudança de uso do solo, o método iWTF e o método de Darcy. A partir desses métodos, estimou-se as taxas de recarga subterrânea, fluxo lateral, variação de armazenamento e percolação profunda. Além disso foram obtidas a variação do nível freático, espessura saturada e gradiente hidráulico horizontal para o aquífero na área de estudo. Durante os anos hidrológicos de 2005 a 2011, a recarga direta variou de 255 e 876 mm (iWTF), equivalente a 21% e 51% da precipitação anual correspondente. Após 2011, com a mudança de cobertura do solo de pastagem para eucalipto, não obstante os anos hidrológicos de 2012 e 2013 apresentarem precipitação próxima da média de longo período, a recarga direta foi estimada em cerca de 210 mm (2012) e 147 mm (2013), equivalentes a 13% e 10% da precipitação anual. A diminuição na recarga direta levou à redução da espessura saturada, variação do nível freático, gradiente hidráulico horizontal, fluxo lateral e armazenamento anual. Além disso, pode-se perceber que a plantação florestal está exercendo influência sobre a área de pastagem adjacente à plantação. Tem-se observado essa influência através da existência de fluxo transversal em direção à plantação florestal, o qual tem elevado o armazenamento no período de estiagem. Os resultados indicam que a plantação de eucalipto afetou significativamente o comportamento sazonal e anual do balanço hídrico na área de estudo. / Historically forest plantations are associated with intense debate about its impact on soil water dynamics or groundwater. Thus, the objective of this study was to evaluate the potential impacts of land cover change of pasture to eucalyptus on the groundwater in an outcrop zone of the Guarani Aquifer System. The study area is located in the Ribeirão da Onça watershed, located in the municipality of Brotas, in the center-east of the state of São Paulo. To assess the impact of land cover change, I used two methods: i. iWTF and ii. Darcy. From these methods, we estimated groundwater recharge rates, lateral flow, water storage variation and deep percolation. Furthermore, I obtained the water table variation, saturated thickness and horizontal hydraulic gradient into the aquifer in the study area. During the hydrological years 2005-2011, the direct recharge through the results of iWTF method varied between 256 and 876 mm, equivalent to 21% and 51% of the corresponding annual precipitation. After 2011, with the land cover change of pasture to eucalyptus, the direct recharge was computed at about 210 mm (2012) and 147 mm (2013), equivalent to 13% and 10% of the annual precipitation. I did not find significant difference in the annual precipitation in these years compared to the historical mean. Therefore, my findings have shown that the decrease of direct recharge are associated to the land cover change of pasture to eucalypts. The decrease in direct recharge leads to the reduction of saturated thickness, the water level variation, horizontal hydraulic gradient, lateral flow and annual storage. Moreover, it can be seen that the forest plantation has influenced the pasture area, adjacent to the plantation. It has been observed that influence through the existence of cross flow toward the forest plantation, which has high storage, especially in the dry season. The results indicate that the eucalyptus plantation significantly affected the seasonal and annual behavior of the water balance in the study area.

In this study, an efficient coupling between Monte Carlo (MC) molecular simulation and Darcy-scale flow in porous media is presented. The cell-centered finite difference method with a non-uniform rectangular mesh were used to discretize the simulation domain and solve the governing equations. To speed up the MC simulations, we implemented a recently developed scheme that quickly generates MC Markov chains out of pre-computed ones, based on the reweighting and reconstruction algorithm. This method astonishingly reduces the required computational time by MC simulations from hours to seconds. In addition, the reweighting and reconstruction scheme, which was originally designed to work with the LJ potential model, is extended to work with a potential model that accounts for the molecular quadrupole moment of fluids with non-spherical molecules such as CO2. The potential model was used to simulate the thermodynamic equilibrium properties for single-phase and two-phase systems using the canonical ensemble and the Gibbs ensemble, respectively. Comparing the simulation results with the experimental data showed that the implemented model has an excellent fit outperforming the standard LJ model. To demonstrate the strength of the proposed coupling in terms of computational time efficiency and numerical accuracy in fluid properties, various numerical experiments covering different compressible single-phase flow scenarios were conducted. The novelty in the introduced scheme is in allowing an efficient coupling of the molecular scale and Darcy scale in reservoir simulators. This leads to an accurate description of the thermodynamic behavior of the simulated reservoir fluids; consequently enhancing the confidence in the flow predictions in porous media.

京都大学 / 0048 / 新制・課程博士 / 博士(農学) / 甲第21151号 / 農博第2277号 / 新制||農||1059(附属図書館) / 学位論文||H30||N5125(農学部図書室) / 京都大学大学院農学研究科地域環境科学専攻 / (主査)教授 村上 章, 教授 川島 茂人, 教授 藤原 正幸 / 学位規則第4条第1項該当 / Doctor of Agricultural Science / Kyoto University / DFAM

This thesis is divided into two projects. The first project investigates the dissolution of the Hanford salt cakes, the chemical properties of the effluent and the physical properties such as viscosity of the effluent, the porosity and the permeability of the salt cake bed as the dissolution proceeds. The chemical results are compared to predictions using a thermodynamic model. Physical properties are important because they govern the rate at which the Hanford tanks can be emptied thus facilitating the remediation process. Two simulants were investigated for the dissolution process. The chemical analysis matched with the model predictions for both the simulants. A typical gibbsite layer formation was observed in the chemically complex simulant and experiments were performed to remediate the layer. The second project of this thesis studied the remediation of sodium phosphate dodecahydrate plug using water and sodium carbonate solutions at varying concentrations. A flow loop previously used to study the sodium phosphate dodecahydrate plugging mechanisms, was used to form a plug followed by the addition of water and sodium carbonate solutions. Results indicate that there was a drastic decrease in time to remediate the plug when sodium carbonate solutions were used.

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Optimizing proppant pack conductivity and proppant-transport and -deposition patterns in a hydraulic fracture is of critical importance to sustain effective and economical production of petroleum hydrocarbons. In this research, a numerical modeling approach, combining the discrete element method (DEM) with the lattice Boltzmann (LB) simulation, was developed to provide fundamental insights into the factors regulating the interactions between reservoir depletion, proppant-particle compaction and movement, single-/multiphase flows and non-Darcy flows in a hydraulic fracture, and fracture conductivity evolution from a partial-monolayer proppant concentration to a multilayer proppant concentration. The potential effects of mixed proppants of different sizes and types on the fracture conductivity were also investigated. The simulation results demonstrate that a proppant pack with a smaller diameter coefficient of variation (COV), defined as the ratio of standard deviation of diameter to mean diameter, provides better support to the fracture; the relative permeability of oil was more sensitive to changes in geometry and stress; when effective stress increased continuously, oil relative permeability increased nonmonotonically; the combination of high diameter COV and high effective stress leads to a larger pressure drop and consequently a stronger non-Darcy flow effect. The study of proppant mixtures shows that mixing of similar proppant sizes (mesh-size-20/40) has less influence on the overall fracture conductivity than mixing a very fine mesh size (mesh-size-100); selection of proppant type is more important than proppant size selection when a proppant mixture is used. Increasing larger-size proppant composition in the proppant mixture helps maintain fracture conductivity when the mixture contains lower-strength proppants. These findings have important implications to the optimization of proppant placement, completion design, and well production. In the hydraulic-mechanical rock-proppant system, a fundamental understanding of multiphase flow in the formation rock is critical in achieving sustainable long-term productivity within a reservoir. Specifically, the interactions between the critical dimensionless numbers associated with multiphase flow, including contact angle, viscosity ratio, and capillary number (Ca), were investigated using X-ray micro computed tomography (micro-CT) scanning and LB modeling. The primary novel finding of this study is that the viscosity ratio affects the rate of change of the relative permeability curves for both phases when the contact angle changes continuously. Simulation results also indicate that the change in non-wetting fluid relative permeability was larger when the flow direction was switched from vertical to horizontal, which indicated that there was stronger anisotropy in larger pore networks that were primarily occupied by the non-wetting fluid. This study advances the fundamental understanding of the multiphysics processes associated with multiphase flow in geologic materials and provides insight into upscaling methodologies that account for the influence of pore-scale processes in core- and larger-scale modeling frameworks. During reservoir depletion processes, reservoir formation damage is an issue that will affect the reservoir productivity and various phases in fluid recovery. Invasion of formation fine particles into the proppant pack can affect the proppant pack permeability, leading to potential conductivity loss. The combined DEM-LB numerical framework was used to evaluate the role of proppant particle size heterogeneity (variation in proppant particle diameter) and effective stress on the migration of detached fine particles in a proppant supported fracture. Simulation results demonstrate that a critical fine particle size exists: when a particle diameter is larger or smaller than this size, the deposition rate increases; the transport of smaller fines is dominated by Brownian motion, whereas the migration of larger fines is dominated by interception and gravitational settling; this study also indicates that proppant packs with a more heterogeneous particle-diameter distribution provide better fines control. The findings of this study shed lights on the relationship between changing pore geometries, fluid flow, and fine particle migration through a propped hydraulic fracture during the reservoir depletion process. / Doctor of Philosophy / Hydraulic fracturing stimulation design is required for unconventional hydrocarbon energy (e.g., shale oil and gas) extraction due to the low permeability and complex petrophysical properties of unconventional reservoirs. During hydrocarbon production, fractures close after pumping due to the reduced fluid pressure and increased effective stress in rock formations. In the oil and gas industry, proppant particles, which are granular materials, typically sand, treated sand, or man-made ceramic materials, are pumped along with fracturing fluids to prevent hydraulic fractures from closing during hydrocarbon extraction. In order to relate the geomechanical (effective stress), geometric (pore structure and connectivity), and transport (absolute permeability, relative permeability, and conductivity) properties of a proppant assembly sandwiched in a rock fracture, a geomechanics-fluid mechanics framework using both experiment and simulation methods, was developed to study the interaction and coupling between them. The outcome of this research will advance the fundamental understanding of the coupled, multiphysics processes with respect to hydraulic fracturing and benefit the optimization of proppant placement, completion design, and well production.