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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
321

Etude et modélisation des transferts d'eau et de sel en milieu deltaïque agricole (Camargue-France) / Study and modeling of water and salt transfers in a farming deltaic environment (Camargue- France)

Torres-Rondon, Laura 19 December 2013 (has links)
L’objectif premier de ce travail est l’étude puis la modélisation numérique 3D du fonctionnement hydrogéologique et salin actuel d’une partie de l’aquifère superficiel de la Moyenne Camargue afin de l’utiliser, dans un second temps, pour la prévision qualitative des modifications induites par le changement climatique. La caractérisation de l’aquifère a été mené selon deux approches : une étude structurale, en utilisant des sondages à la tarière et différentes techniques géophysiques (ERT, ES et cartographie EM), et une étude hydrogéologique, intégrée par plusieurs campagnes de pompages, suivi piézométrique et des prélèvements de l’eau souterraine. Cette méthodologie a servi pour caractériser la géométrie de l’aquifère superficiel ainsi que son fonctionnement actuel et les processus qui l’affectent. Divers phénomènes environnementaux ont été identifiés, tels que : un lessivage du sol grâce à l’action de l’irrigation, un endoréisme observé dans les zones basses produit par l’effet de l’évaporation, et la reproduction des fluctuations de l’étang de Vaccarès dans la piézométrie, jusqu’au moins 30 m de la rive. Le modèle numérique construit à partir des observations du terrain reproduit les principaux processus observés. Il met en évidence un possible flux sortant vers le Vaccarès et le rôle important du marais dans l’hydrodynamique et le comportement hydrosalin du système. Les résultats du modèle face aux différents scénarios de prédiction montrent une intrusion d’eau du Vaccarès et, donc, une salinisation du système induit par la remontée du niveau marin, ainsi que la présence de l’irrigation et le marais comme facteurs essentiels dans la neutralisation de cette salinisation. / The main objective in this investigation is to construct a representative 3D numerical groundwater flow model of a local superficial aquifer in the Medium Camargue plain to simulate the actual hydrogeological and salt behavior. The 3D model will be used, in a second time, to simulate modifications of the system behavior provide by climate changes. The characterization of the aquifer was carried out by two approaches: a structural survey, using auger drilling technique and some geophysics techniques (EM mapping ERT, ES and), and a hydrogeological survey composed by several pumping tests, piezometric monitoring and groundwater samples. The methodological approach used allowed characterizing the geometry, behavior of the system and the process governing performance of the superficial aquifer. Several environmental phenomena were been identified, such as: a soil’s leaching; an endorheic phenomenon at the lower elevation areas; and the reproduction of the Vaccares pond’s fluctuations at the water table, until 30 m from shore. The numerical model, which has been constructed through field observations, reproduces principal process of the aquifer. This model highlights a possible outflow from the aquifer to the Vaccares pond and the important role of marsh in the hydrodynamic and hydrosaline behavior of the system. The results of the prediction scenarios tested with the numerical model highlights a possible intrusion from Vaccares water and, therefore, a salinization of the system produced by increase of sea level rise. The important presence of the irrigation and the marsh to neutralize a future salinization has been exposed.
322

Ordenamento do uso e ocupação do solo na planície fluviolagunar do rio Betume e adjacências

Lima, Luana Pereira 20 February 2017 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / Coastal environments are complex due to their natural dynamics, fragilities and multiple socioeconomic interests. They are peculiar environments and of differentiated character, that must be considered in their singularity, and they need special attention for a correct planning and management. The new rationality of occupation of the coastal environments associates the demand of a leisure society with a demand for zones of work and housing. Given this, there is a need for studies that present proposals for environmental planning aiming at a balance between the use and maintenance of natural resources. The purpose of this study was to analyze in an integrated way the environmental and socioeconomic dynamics of the fluvio lagoon plain associated with the Betume River and its surroundings from the perspective of land use and land use planning. In order to do so, the systemic approach was adopted as a way of researching the landscape, which made it possible to understand the reality and thus propose a zoning resulting from the application of the pressure-state-impact-response methodology. Bibliographical review, documentary research, field work, cartographic document elaboration, were the methodological procedures adopted and subsidized the integrated analysis of the environmental and social dimensions that culminated in a zoning proposal. The plain formed by fluvio lagoons deposits associated with the Betume River has a geological-geomorphologic evolution developed from events of transgressions and marine regressions of the Quaternary and is inserted between dunes strands in marine and paleo cliffs terraces of the Barreiras Group. Its structure points to a level of marked environmental fragility. In contrast, the uses attributed to this environment have shown growth, namely: activities and interests aimed at tourism; Primary economic activities of fishing, shrimp farming, pasture, agriculture and plant extractive activities. The level of occupation is unevenly distributed, as is the intensity of modification and degradation. Zoning, from environmental and socioeconomic diagnostics, proposes guidelines for land use and occupation in order to sustain environmental quality. / Os ambientes costeiros são complexos devido sua dinâmica natural, fragilidades e os múltiplos interesses socioeconômicos. São ambientes peculiares e de caráter diferenciado, que devem ser considerados em sua singularidade, e necessitam de atenção especial para um correto planejamento e gestão. A nova racionalidade de ocupação dos ambientes costeiros associa a demanda de uma sociedade de lazer a uma demanda por zonas de trabalho e habitação. Diante disso, há a necessidade de estudos que apresentem propostas de ordenamento ambiental visando um equilíbrio entre o uso e a manutenção dos recursos naturais. A proposta desse estudo foi analisar de forma integrada a dinâmica ambiental e socioeconômica da planície fluviolagunar associada ao rio Betume e adjacências na perspectiva do ordenamento do uso e ocupação do solo. Para tanto foi adotada a abordagem sistêmica como caminho de investigação da paisagem, que possibilitou entender a realidade e assim propor um zoneamento resultante da aplicação da metodologia pressão-estado-impacto-resposta. Revisão bibliográfica, pesquisa documental, trabalhos de campo, elaboração de documentos cartográficos, foram os procedimentos metodológicos adotados e subsidiaram a análise integrada das dimensões ambiental e social que culminaram em uma proposta de zoneamento. A planície formada por depósitos fluviolagunares associada ao Rio Betume tem uma evolução geológico-geomorfológica desenvolvida a partir de eventos de transgressões e regressões marinhas do Quaternário e encontra-se inserida entre cordões de dunas em terraços marinhos e paleofalésias do Grupo Barreiras. Sua estrutura aponta um nível de fragilidade ambiental acentuado. Em contrapartida os usos atribuídos a esse ambiente tem apresentado crescimento, a saber: atividades e interesses voltados para o turismo; atividades econômicas primárias de pesca, carcinicultura, pastagens, agricultura e atividades de extrativismo vegetal. O nível de ocupação está distribuído de forma irregular, assim como a intensidade de modificação e degradação. O zoneamento, oriundo dos diagnósticos ambiental e socioeconômico, propõe orientações de uso e ocupação do solo visando a sustentação da qualidade ambiental. / São Cristóvão, SE
323

The Familiar Foreign Country: Reading Mexico in Cormac McCarthy, Jack Kerouac, and Katherine Anne Porter

Ligairi, Rachel Mae 12 July 2006 (has links)
My thesis examines the discourse of Mexico in the works of three twentieth-century American authors-Cormac McCarthy, Jack Kerouac, and Katherine Anne Porter-in order to analyze representations of Otherness in modernism and postmodernism. I seek to destabilize the dividing line between these periods as well as to show how representation in postmodernity has become more problematic due in large part to the proliferation of consumer culture. Though the Mexico that McCarthy employs in Blood Meridian and the Border Trilogy (All the Pretty Horses, The Crossing, and Cities of the Plain) escapes many stereotypes, his Mexico is merely a staging ground that he uses to examine postmodern questions of philosophy while deconstructing myths such as the Old West and Manifest Destiny and reflecting on the ramifications of World War II. Therefore, McCarthy elides Mexico by using its Otherness as a mirror that enables reflection on the Self. Kerouac too is interested in using Mexico to solve U.S. problems. In On the Road, Kerouac's fictional counterpart, Sal Paradise, searches for the authenticity missing from middle-class American life by ultimately turning to the "authentic" Mexico. Though he is able to distinguish between simulations and reality in his own cultural context, once south of the border Sal misrecognizes what is a hypperreal Mexico for supreme authenticity. By contrast, when Katherine Anne Porter crosses the border, she is quick to identify corruption and revolutionary failure in Mexico. When pieces such as "Xochimilco" and "María Concepción" are placed alongside that of the work of Diego Rivera, a leader in the Mexican muralist movement, it becomes clear that Porter essentializes her Mexican subjects with the specific political goal in mind of furthering the revolution. Additionally, by crossing the generic lines separating fiction and non-fiction, Porter approximates what could be called a postmodern form of ethnography. Yet all of her representational strategies are tempered, especially in her last Mexican story, Hacienda, by an awareness that representations of Other cannot be other than flawed.
324

Kvantitativní hodnocení kvality CT RTG zobrazení / CT X-ray quantitative evaluation

Novotný, Lukáš January 2009 (has links)
X-Ray Computed Tomography is irreplaceable medical imaging system. Quantitative evaluation is day to day routine used for clean run of this imaging system. The master’s thesis is focused on quantitative evaluation of first and third generation X-Ray CT. First of all is about subjective and objective evaluation of space and energetic resolution. Space resolution is evaluated in space and frequency domain. Energetic resolution is represent by low contrast resolution method. Application “Kvantitativní hodnocení kvality CT RTG zobrazení” created for this thesis is used for creation of reconstruction image and quantitative evaluation. This application was created with consideration of its usage in subjects about image processing. The master’s thesis contains results of quantitative evaluation X-Ray CT created with this application and proposal of lab work.
325

Analýza porušování kvazikřehkých materiálů za použití numerického modelování a akustické/elektromagnetické emise / Analysis of fracture of quasibrittle materials using numerical modelling and acoustic/electromagnetic emission

Vodák, Ondřej January 2013 (has links)
This master thesis gives overview of non-destructive tests of concrete and provides detailed information concerning the acoustic and electromagnetic emission during monitoring of concrete failure. Conducted loading tests of plain concrete specimens are described in the thesis together with the performed numerical simulations of these tests in the software ATENA. The simulation results of concrete failure are analysed in detail and compared with the experimental results recording failure processes with the help of acoustic and electromagnetic emission. The majority of simulation results in software ATENA 3D show good agreement with the recorded data.
326

Mateřská škola v Českých Budějovicích / Day-care center in České Budějovice

Šturma, Pavel January 2015 (has links)
The master’s thesis on the topic Kindergarten is processed in the form of project documentation for the implementation of the new building Kindergarten. Project documentation is designed to meet the applicable standards. The building is designed in the catastral of the city of České Budějovice. The building has two floors and it‘s designed from Porotherm with contact thermal insulation system, roofed by warm flat green roof and based on the footings of plain concrete. The ceiling construction is deigned from the prestressed concrete ceiling panels. The building contains three classes for a total of 60 children. Food and washing bedding is provided by imports.
327

Chování kluzných ložisek řadového pětiválcového motoru při různých provozních podmínkách / Behaviour of Plain Bearings under Various Working Conditions

Lábus, Jiří January 2008 (has links)
This diploma thesis is devoted to problems of crankshaft plain bearings at five-cylinder in-line engine. Document body describes behaviour of plain bearings under various working conditions. To needs of the hydrodynamic bearings simulations is created the cranktrain virtual model. Next part of hereof document deals with problems of bearing shell design. Is created survey of the bearing materials and shortly described technological processing of shell bearing. To understand complicated problems hydrodynamic lubrication is derived Reynolds differential equation and foreshadowed succession calculation dynamically loaded bearings. In final parts of this thesis are presented most interesting results obtained from computational analysis.
328

Hydrodynamická ložiska šestiválcového vznětového motoru / Plain Bearings of Six-cylinder CI Engine

Hruška, Miroslav January 2011 (has links)
This master’s thesis focuses on hydrodynamic plain bearing drivetrain in-line sixcylinder diesel tractor engine. In the first part is used as reported in contemporary bearing materials and design solutions bearing basins. Furthermore, given the general Reynolds equation of hydrodynamic lubrication. The main part of the thesis is devoted to creating a virtual model of the crank mechanism in MBS system ADAMS/Engine. Rigid crankshaft in this model is replaced by the flexible crankshaft, which is prepared in the FEM software ANSYS and then exported. The final section presents the results of simulations and their evaluation.
329

A vegetation classification and description of five wetland systems and their respective zones on the Maputaland Coastal Plain

Pretorius, Mathilde Luïse 02 1900 (has links)
The Maputaland Coastal Plain in Kwa Zulu-Natal is covered by aeolian sands . According to the national wetland delineation manual delineating wetlands in this area is complex due to problematic wetland soils. The aim of this study was to classify and describe the vegetation of the different zones of the wetland systems to determine the main drivers of the plant communities. The understanding of these complex ecosystems could assist in wetland delineation. Twenty wetlands from five wetland systems were surveyed. The vegetation zones of each wetland were sampled and basic environmental data were collected. The results from this study indicate that different plant species assemblages are characteristic for the wetland zones. However, zone delineation using vegetation composition varies between the different wetland systems, and should be evaluated according to the system in question. The major determinants of the vegetation communities in wetlands on the MCP are the substrate type and hydrological regime / Environmental Sciences / M.Sc. (Environmental Management)
330

Mezi Nostalgií a Pragmatismem: 'Hraniční Trilogie' Cormaca McCarthyho. / Between Nostalgia and Pragmatism: Cormac McCarthy's 'Border Trilogy.'

Polívka, Zdeněk January 2019 (has links)
THESIS ABSTRACT This thesis deals with the problematics and the role of American frontier and American West in Cormac McCarthy's border trilogy consisting of All the Pretty Horses (1992), The Crossing (1994) and Cities of the Plain (1999). The reading proper focuses mainly on the second novel of the trilogy, making frequent references to both the other two volumes of the trilogy and to Blood Meridian (1985), a novel directly preceding the trilogy itself. The main goal of the thesis is to demonstrate that the trilogy not only critically engages with the American nationalist ideology represented by a nostalgically conceptualized myths of the American frontier, but that it also offers its own alternative vision of the concept of the frontier and of American national identity. The thesis further claims that McCarthy's critical approach to the mythical representations of the American history bears strong resemblance to the philosophy of American pragmatism as defined by a French philosopher Giles Deleuze in his works dedicated to American thinking and culture. In his pragmatic view of American identity the frontier ceases to function in its traditional, nationalistic sense as a line of separation that divides the social and political space into binary categories, and instead it is understood as an open and...

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