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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.
21

Computational Study of Critical Flow Discharge in Supercritical Water Cooled Reactors

Chatharaju, Madhuri 10 1900 (has links)
<p>Supercritical Water-cooled Reactor (SCWR) is a Generation-IV nuclear reactor design that operates on a direct energy conversion cycle above the thermodynamic critical point of water (374<sup>0</sup>C and 22.1 MPa), and offers higher thermal efficiency and considerable design simplification. As an essential step in the design of SCWR safety systems, the accident behaviour of the reactor is evaluated to ensure that the safety systems can achieve safe shutdown for all the design basis accidents. Unfortunately, the computational tools and computer codes that are currently employed for safety analysis have little application in the supercritical region, and faces significant challenges in simulating the transitions from subcritical to supercritical conditions.</p> <p>This thesis examines the predictive capabilities of Computational Fluid Dynamics (CFD) code STAR-CCM+ by evaluating critical flow (or choked flow) due to accidental release of coolant from supercritical fluid systems. The biggest challenge of this research is that the current version of STAR-CCM+ does not support supercritical simulations because the steam tables included in the package are only limited to the subcritical subset of the thermodynamic fluid properties.</p> <p>The research was carried out in two stages. In the first stage, the CFD code STAR-CCM+ was customized to simulate supercritical conditions by, (i) Generating updated steam tables to include subcritical and supercritical fluid properties and using more pressure and temperature points in the pseudo critical region (22 – 25 MPa, 645 -660 K) to handle the rapid changes in the fluid properties, and (ii) Implementing a multi-dimensional steam table interpolation scheme to access the fluid property data at any thermodynamic state during the simulation. In the second stage, the customized CFD code was extensively evaluated by simulating several accidental release scenarios from supercritical conditions using rounded-edge and sharp-edge nozzles and the model results were validated with experimental data. To overcome the solution stability (or convergence) issues encountered during the supercritical simulations, a fine tuning procedure was proposed that guaranteed convergence for all the case studies considered in this thesis.</p> <p>The simulation results revealed that the CFD model produced results that were in good agreement with experimental data and only about 10% prediction error was noticed for most cases considered in the thesis. Considering the sensitivity of the CFD model for upstream temperatures and pressures, these results appear to be quite reasonable. From the computational experience gained in this research , we believe that the CFD code STAR-CCM+ is a very useful tool to perform thermal hydraulic simulations for supercritical systems. However, an appropriate customization and extensive validation of the code is required before it can be exclusively used for safety analysis.</p> / Master of Applied Science (MASc)
22

Identification des conditions de rupture fragile des gainages combustibles en alliage de zirconium oxydés sous vapeur d’eau à haute température et trempés sous charge axiale / Identification of brittle fracture conditions of zirconium alloy fuel claddings oxidized under steam at high temperature and quenched under axial loading

Thieurmel, Ronan 14 September 2018 (has links)
Lors d’un scénario hypothétique d’Accident par Perte de Réfrigérant Primaire (APRP), les gainages combustibles en alliage de zirconium subissent des sollicitations thermomécaniques sévères dans des environnements chimiques très oxydants. L’évolution des conditions de pression et de température ainsi que la présence du fluide réfrigérant peuvent entraîner dans un premier temps le ballonnement-éclatement puis l’oxydation sous vapeur et la prise d’hydrogène à haute température ainsi que des chargements mécaniques axiaux lors du renoyage final.L’objectif de la thèse est d’identifier les mécanismes et les paramètres clés qui gouvernent la rupture lors de la phase de renoyage sous traction. Des essais semi-intégraux, visant à reproduire un scénario APRP sur des tronçons de gaines de Zircaloy−4, ont été réalisés afin d’étudier le comportement de ce matériau dans de telles conditions.Un seuil fonction de la durée d’oxydation à haute température, à partir duquel la gaine rompt lors du renoyage, est mis en évidence. Deux lieux de rupture sont identifiés : la zone ballonnée où l’oxydation est maximale et la prise d’hydrogène nulle, ainsi que la zone dite « d’hydruration secondaire », sous la zone ballonnée, où la prise d’hydrogène est conséquente et l’oxydation moindre. Par ailleurs, un scénario de la rupture par rapport à la chronologie du renoyage a été établi.Cependant, le traitement macroscopique de ces essais ne permet pas de discriminer ces deux lieux de rupture, car la rupture intervient indépendamment dans le ballon et hors zone ballonnée en fonction du transitoire appliqué et de la morphologie du ballonnement-éclatement. Une approche locale a été mise en place, à partir de la caractérisation microstructurale et fractographique systématique des éprouvettes d’essai, afin d’établir un critère de rupture dépendant de l’état du matériau.La distribution complexe des éléments chimiques et des phases dans l’épaisseur de la gaine a été déterminée. Les changements de phase dans le ballon fortement oxydé, menant à une microstructure globalement fragile, ont été explicités. Une loi de seuil à rupture, en zone d’hydruration secondaire, a été identifiée à l’aide des mesures d’épaisseurs de phases et du profil de teneur en hydrogène. / During hypothetical Loss-Of-Coolant-Accident (LOCA) scenarios, zirconium alloy fuel cladding tubes are subjected to severe thermo- mechanical loading conditions in highly oxidising chemical environments. Pressure and temperature evolution together with cooling water can lead to ballooning and burst followed by steam oxidation and hydrogen uptake at high temperature, and then axial loading during the final reflooding stage.This study focuses on the identification of mechanisms and key parameters which drive cladding fracture during the reflooding stage under axial tensile load.Laboratory-scale semi-integral tests simulating LOCA transients on Zircaloy−4 test rods have been realised. A fracture/no-fracture threshold of oxidation duration at high temperature has been determined. Two fracture locations have been identified: i) the burst zone with maximal oxidation and no hydrogen uptake, and ii) the “secondary hydriding” zone below the burst zone, with substantial hydrogen absorption and lower oxidation levels. Moreover, a scenario of fracture as a function of the reflooding chronology has been identified. Nevertheless, the macroscopic treatment of these tests has not permitted to discriminate these two fracture locations because fracture independently occurs in and out of the burst zone, whatever the applied transient and the balloon and burst morphologies.From systematic microstructural and fractographic characterisation of test specimens, a local approach aiming at identifying a fracture threshold as a function of the microstructural state of the material has been applied. The complex distribution of chemical elements and phases across the cladding thickness has been determined. Phase transformations in the highly-oxidised balloon, leading to a globally brittle microstructure have been explicated. In the secondary hydriding zone, a fracture threshold criterion has been identified by means of layer thickness measurements and hydrogen uptake profile.
23

Effet de fortes teneurs en hydrogène sur les propriétés métallurgiques et mécaniques des gaines en alliage de zirconium après incursion à haute température / Influence of high hydrogen content, on microstructure and mechanical behaviour, of zirconium alloys fuel cladding upon and after cooling from high temperature

Turque, Isabelle 19 September 2016 (has links)
En conditions hypothétiques d’accident par perte de réfrigérant primaire, la gaine en alliage de zirconium des crayons combustibles des réacteurs nucléaires à eau pressurisée peut être temporairement exposée à de la vapeur d’eau à haute température (jusqu’à 1 200°C) avant d’être refroidie puis trempée à l’eau. Dans certaines conditions, après éclatement, la gaine peut absorber une quantité très importante d’hydrogène (hydruration secondaire), pouvant atteindre 3 000ppm mass. localement, lors du maintien sous vapeur d’eau à haute température.Cette étude porte sur l’effet, peu étudié jusqu’alors, de fortes concentrations en hydrogène sur les caractéristiques métallurgiques et mécaniques de deux alliages de zirconium, le Zircaloy-4 et le M5®, au cours et après refroidissement depuis le domaine des hautes températures, auxquelles le zirconium est en phase β. Un protocole a été mis au point afin de charger en hydrogène, de manière homogène jusqu’à ~3 000ppm-mass., des tronçons de tube de gainage de plusieurs centimètres de long. Les transformations de phases, la ségrégation des éléments chimiques et la précipitation des hydrures lors du refroidissement depuis le domaine d’existence de la phase β du zirconium ont été étudiées, pour les matériaux contenant jusqu’à ~3 000ppm-mass. d’hydrogène en moyenne, au moyen de différentes techniques : diffraction de neutrons in-situ en cours de refroidissement depuis 700°C, diffraction de rayons X, µ-ERDA, et microscopie électronique notamment. Les résultats ont été confrontés à des prévisions thermodynamiques. Puis, pour étudier l’effet de fortes teneurs en hydrogène sur le comportement mécanique de la phase (ex-)β du zirconium, des essais de traction axiale ont été effectués à différentes températures entre 20 et 700°C, au cours du refroidissement depuis le domaine de phase β, sur des échantillons contenant jusqu’à ~3 000ppm-mass. d’hydrogène en moyenne. Les résultats montrent que les propriétés métallurgiques et mécaniques de la phase (ex-)β des alliages de zirconium dépendent fortement de la température et de la teneur en hydrogène. / Under hypothetical loss-of-coolant accident conditions, fuel cladding tubes made of zirconium alloys can be exposed to steam at high temperature (up 1 200°C) before being cooled and then quenched in water. In some conditions, after burst occurrence the cladding can rapidly absorb a significant amount of hydrogen (secondary hydriding), up to 3 000wt.ppm locally, during steam exposition at HT.The study deals with the effect, poorly studied up to date, of high contents of hydrogen on the metallurgical and mechanical properties of two zirconium alloys, Zircaloy-4 and M5®, during and after cooling from high temperatures, at which zirconium is in its β phase. A specific facility was developed to homogeneously charge in hydrogen up to ~3 000wt.mass. cladding tube samples of several centimeters in length. Phase transformations, chemical element partitioning and hydrogen precipitation during cooling from the β temperature domain of zirconium were studied by using several techniques, for the materials containing up to ~3 000wt.ppm of hydrogen in average: in-situ neutron diffraction upon cooling from 700°C, X-ray diffraction, µ-ERDA, EPMA and electron microscopy in particular. The results were compared to thermodynamic predictions. In order to study the effect of high hydrogen contents on the mechanical behavior of the (prior-)β phase of zirconium, axial tensile tests were performed à various temperatures between 20 and 700°C upon cooling from the β temperature domain, on samples with mean hydrogen contents up to ~3 000ppm-mass.The results show that metallurgical and mechanical properties of the (prior-)β phase of zirconium alloys strongly depend on temperature and hydrogen content.
24

A multiplicidade do sujeito de fronteira : as feridas abertas nas narrativas borderlands La frontera, de Gloria Anzaldúa, e Dois irmãos, de Milton Hatoum

Silva, Fidelainy Sousa January 2017 (has links)
A organização da sociedade atual acontece em decorrência dos encontros entre culturas, sejam por meio de tragédias naturais, guerras mundiais, diásporas, reconfiguração de fronteiras ou da hibridização cultural. Nessa perspectiva, o objetivo desta pesquisa é investigar a construção da multiplicidade do Ser de fronteira a partir da perspectiva da escritora chicana Gloria Anzaldúa e do amazonense Milton Hatoum nas narrativas Borderlands/La frontera: The New Mestiza (1987), e Dois Irmãos (2000), respectivamente. Partindo das questões identitárias, o caminho para a análise das narrativas transita pelo espaço ficcional na intenção de evidenciar os deslocamentos e os fluxos migratórios das personagens como articuladores para compreender as feridas abertas nos espaços de fronteira. No decorrer da investigação foi possível ressignificar a fronteira como locus da diferença cultural e fragmentação para contrapor a ideia de que os lugares fronteiriços são fixos ou funcionam com divisores de sistemas culturais. Para desenvolver o trabalho, utilizo os métodos comparatistas e de aporte teórico da corrente culturalista. Uso os conceitos-chave de Walter Mignolo sobre a colonialidade do saber e de Stuart Hall e Homi Bhabha sobre as identidades heterogêneas. Na corrente filosófica, Jacques Derrida, com a teoria desconstrucionista, e Gilles Deleuze e Félix Guattari, com o rizoma e a teoria dos agenciamentos. Esse aporte é o fio condutor do debate sobre a modernidade tardia e da diferença cultural, tendo em vista espaços elaboradores de sujeitos marginalizados, periféricos, excluídos e silenciados. Sendo assim, a negação da postura essencialista, a partir da leitura das obras, serve de estratégia analítica e de compreensão da ferida aberta como espaço da multiplicidade dos sujeitos em regiões de fronteira. / Nowadays society’s structure is built upon/on encounters between cultures, natural tragedies, world wars, diasporas, reconfiguration of borders and cultural hybridization. Thus, the aim of this research is to investigate the construction of the multiplicity of the Frontier Self as it is through the approach of the Chicano writer Gloria Anzaldúa and in the approach of the Amazonian writer Milton Hatoum in Borderlands/La frontera: The New Mestiza (1987) and Dois Irmãos (2000), respectively. Considering the identity issues, the analysis of the narratives transits/moves/focuses on through the fictional space to highlight the displacements and the migratory flows of the characters as articulators in order to understand the open wounds in border spaces. Therefore, during the research, it was possible to re-signify the frontier as a locus of cultural difference and fragmentation to counteract the idea that frontier places are fixed or function as divisors of cultural systems. To develop this work, I apply comparative and theoretical methods within the culturalist approach as well as the key concepts of Walter Mignolo on the coloniality of knowledge, and Stuart Hall and Homi Bhabha on heterogeneous identities. The denial of the essentialist position, based on the reading of the works, serves as an analytical strategy and understanding of the open wound as the space of the multiplicity in border regions.
25

A multiplicidade do sujeito de fronteira : as feridas abertas nas narrativas borderlands La frontera, de Gloria Anzaldúa, e Dois irmãos, de Milton Hatoum

Silva, Fidelainy Sousa January 2017 (has links)
A organização da sociedade atual acontece em decorrência dos encontros entre culturas, sejam por meio de tragédias naturais, guerras mundiais, diásporas, reconfiguração de fronteiras ou da hibridização cultural. Nessa perspectiva, o objetivo desta pesquisa é investigar a construção da multiplicidade do Ser de fronteira a partir da perspectiva da escritora chicana Gloria Anzaldúa e do amazonense Milton Hatoum nas narrativas Borderlands/La frontera: The New Mestiza (1987), e Dois Irmãos (2000), respectivamente. Partindo das questões identitárias, o caminho para a análise das narrativas transita pelo espaço ficcional na intenção de evidenciar os deslocamentos e os fluxos migratórios das personagens como articuladores para compreender as feridas abertas nos espaços de fronteira. No decorrer da investigação foi possível ressignificar a fronteira como locus da diferença cultural e fragmentação para contrapor a ideia de que os lugares fronteiriços são fixos ou funcionam com divisores de sistemas culturais. Para desenvolver o trabalho, utilizo os métodos comparatistas e de aporte teórico da corrente culturalista. Uso os conceitos-chave de Walter Mignolo sobre a colonialidade do saber e de Stuart Hall e Homi Bhabha sobre as identidades heterogêneas. Na corrente filosófica, Jacques Derrida, com a teoria desconstrucionista, e Gilles Deleuze e Félix Guattari, com o rizoma e a teoria dos agenciamentos. Esse aporte é o fio condutor do debate sobre a modernidade tardia e da diferença cultural, tendo em vista espaços elaboradores de sujeitos marginalizados, periféricos, excluídos e silenciados. Sendo assim, a negação da postura essencialista, a partir da leitura das obras, serve de estratégia analítica e de compreensão da ferida aberta como espaço da multiplicidade dos sujeitos em regiões de fronteira. / Nowadays society’s structure is built upon/on encounters between cultures, natural tragedies, world wars, diasporas, reconfiguration of borders and cultural hybridization. Thus, the aim of this research is to investigate the construction of the multiplicity of the Frontier Self as it is through the approach of the Chicano writer Gloria Anzaldúa and in the approach of the Amazonian writer Milton Hatoum in Borderlands/La frontera: The New Mestiza (1987) and Dois Irmãos (2000), respectively. Considering the identity issues, the analysis of the narratives transits/moves/focuses on through the fictional space to highlight the displacements and the migratory flows of the characters as articulators in order to understand the open wounds in border spaces. Therefore, during the research, it was possible to re-signify the frontier as a locus of cultural difference and fragmentation to counteract the idea that frontier places are fixed or function as divisors of cultural systems. To develop this work, I apply comparative and theoretical methods within the culturalist approach as well as the key concepts of Walter Mignolo on the coloniality of knowledge, and Stuart Hall and Homi Bhabha on heterogeneous identities. The denial of the essentialist position, based on the reading of the works, serves as an analytical strategy and understanding of the open wound as the space of the multiplicity in border regions.
26

A palavra do habitante e as possibilidades de apropria??o do habitat em loca??o social: o programa de loca??o social da prefeitura municipal de S?o Paulo

Andrade, Sarah de Andrade e 23 September 2016 (has links)
Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2017-04-03T19:44:45Z No. of bitstreams: 1 SarahDeAndradeEAndrade_DISSERT.pdf: 15836321 bytes, checksum: 563db1cb792c82318fd2bb897d88531f (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2017-04-05T21:23:15Z (GMT) No. of bitstreams: 1 SarahDeAndradeEAndrade_DISSERT.pdf: 15836321 bytes, checksum: 563db1cb792c82318fd2bb897d88531f (MD5) / Made available in DSpace on 2017-04-05T21:23:15Z (GMT). No. of bitstreams: 1 SarahDeAndradeEAndrade_DISSERT.pdf: 15836321 bytes, checksum: 563db1cb792c82318fd2bb897d88531f (MD5) Previous issue date: 2016-09-23 / A pesquisa aqui desenvolvida, trata das possibilidades de apropria??o do habitat concebido pelo Programa de Loca??o Social (PLS), implementado no ?mbito da Prefeitura Municipal de S?o Paulo (PMSP), por seus habitantes. Orientada pelo referencial te?rico-metodol?gico do fil?sofo e soci?logo franc?s Henri Lefebvre (1958; 1970; 1974; 2002; 2001, 2008; 2013) e pela aplica??o do m?todo de an?lise do discurso desenvolvido pelos pesquisadores do Instituto [franc?s] de Sociologia Urbana (ISU), investiga a rela??o entre a ?palavra do habitante? (RAYMOND, 2001; HAUMONT, 2001, RAYMOND et. al, 2001) e a apropria??o da loca??o social em S?o Paulo. O m?todo aqui relido e aplicado faz uso de entrevistas abertas/n?o estruturadas ? complementadas por nossa observa??o in loco e registro fotogr?fico - para a apreens?o do espa?o percebido pelos habitantes do referido programa, entendendo que esta ferramenta coloca em posi??o de centralidade e d? voz ao agente principal da pesquisa: o habitante. Assim, o recorte espacial de nosso campo emp?rico abrange quatro dos seis empreendimentos viabilizados pelo mesmo entre 2002 e 2015, sendo eles a Vila dos Idosos, o Residencial Olarias, o Edif?cio Senador Feij? e o Palacete dos Artistas. A utiliza??o de uma abordagem qualitativa e, especificamente, a aplica??o do m?todo palavra do habitante possibilitou a formula??o de diversas conclus?es que extrapolam a hip?tese inicialmente formulada de que a reafirma??o do valor da propriedade privada pelas pol?ticas habitacionais brasileiras, fragilizaria as possibilidades de apropria??o do habitat de loca??o social. Essa quest?o se coloca como um dos entraves ? apropria??o do habitat fundamentado no aluguel e, do ponto de vista qualitativo e quantitativo, tamb?m est?o presentes no discurso dos habitantes, os conflitos resultantes da descontinuidade no acompanhamento s?cioeducativo aos benefici?rios do Programa e seu abandono pelas gest?es que se sucedem na PMSP entre 2005 e 2013. Por outro lado, nos empreendimentos onde as fam?lias e ind?viduos est?o engajados em movimentos sociais de luta por moradia e estes atuam como uma ponte entre os habitantes e os ?rg?os p?blicos de gest?o dos empreendimentos, se evidenciam as possibilidades de supera??o dos conflitos e condu??o ? apropria??o do habitat. Ao longo dos caminhos aqui trilhados, descortinamos tamb?m a apropria??o dos idosos pelo habitat em loca??o social, que n?o compartilham do sonho da casa pr?pria. / This research verses about the possibilities of habitat appropriation conceded by Social Tenancy Program (PLS), implemented in the sphere of the S?o Paulo City Hall, by its inhabitants. Oriented by the theories and methods of the french sociologist and philosopher Henri Lefebvre (1958; 1970; 1974; 2002; 2001; 2008; 2013) and by the application of the discourse analysis method developed by researches of the French Urban Sociology Institute (ISU), the current research investigates the relationship between the ?inhabitant?s word? (RAYMOND, 2001; HAUMONT, 2001, RAYMOND et. al, 2001) and the appropriation of social tenancy in S?o Paulo. The method here employed and reviewed makes use of open and non-structured interviews ? complemented by field observation and photographic registers ? for the setting of the space perceived by those contemplated by the Program, understanding that this tool brings to the fore the main agent of this research: the inhabitant. Thus, the spatial limits of our empirical field embraces four of the six buildings contemplated by the program between 2002 and 2015, being the Vila dos Idosos, Residencial Olarias, Senador Feij? Building and the Palacete dos Artistas. The use of a qualitative and, specifically, the application of the method ?inhabitant?s word, made possible the formulation of several conclusions that go beyond the initial hypothesis that said that the reaffirming of the private propriety value by brazilian habitational policies would bring frailty to the possibilities of social tenancy of habitat appropriation. This matter presents itself as one of the difficulties for the appropriation of habitat by rent and, from qualitative and quantitative points of view, they are also present in the inhabitants? discourse, the resulting conflicts from the cancelling of the socio-educative accompaniment of the ones contemplated by the Program and its abandon by the successive terms in the City Hall between 2005 and 2013. On the other hand, in the buildings that there are families and individuals that are engaged in social movements for livelihood, they act as a bridge that links the inhabitants and the public management of the buildings, and is also noticed the possibilities of conflict solving and appropriation of habitat. Throughout this research we also verse about the appropriation of habitats by the elderly population in social tenancy, who share not the dream to own a house.
27

A multiplicidade do sujeito de fronteira : as feridas abertas nas narrativas borderlands La frontera, de Gloria Anzaldúa, e Dois irmãos, de Milton Hatoum

Silva, Fidelainy Sousa January 2017 (has links)
A organização da sociedade atual acontece em decorrência dos encontros entre culturas, sejam por meio de tragédias naturais, guerras mundiais, diásporas, reconfiguração de fronteiras ou da hibridização cultural. Nessa perspectiva, o objetivo desta pesquisa é investigar a construção da multiplicidade do Ser de fronteira a partir da perspectiva da escritora chicana Gloria Anzaldúa e do amazonense Milton Hatoum nas narrativas Borderlands/La frontera: The New Mestiza (1987), e Dois Irmãos (2000), respectivamente. Partindo das questões identitárias, o caminho para a análise das narrativas transita pelo espaço ficcional na intenção de evidenciar os deslocamentos e os fluxos migratórios das personagens como articuladores para compreender as feridas abertas nos espaços de fronteira. No decorrer da investigação foi possível ressignificar a fronteira como locus da diferença cultural e fragmentação para contrapor a ideia de que os lugares fronteiriços são fixos ou funcionam com divisores de sistemas culturais. Para desenvolver o trabalho, utilizo os métodos comparatistas e de aporte teórico da corrente culturalista. Uso os conceitos-chave de Walter Mignolo sobre a colonialidade do saber e de Stuart Hall e Homi Bhabha sobre as identidades heterogêneas. Na corrente filosófica, Jacques Derrida, com a teoria desconstrucionista, e Gilles Deleuze e Félix Guattari, com o rizoma e a teoria dos agenciamentos. Esse aporte é o fio condutor do debate sobre a modernidade tardia e da diferença cultural, tendo em vista espaços elaboradores de sujeitos marginalizados, periféricos, excluídos e silenciados. Sendo assim, a negação da postura essencialista, a partir da leitura das obras, serve de estratégia analítica e de compreensão da ferida aberta como espaço da multiplicidade dos sujeitos em regiões de fronteira. / Nowadays society’s structure is built upon/on encounters between cultures, natural tragedies, world wars, diasporas, reconfiguration of borders and cultural hybridization. Thus, the aim of this research is to investigate the construction of the multiplicity of the Frontier Self as it is through the approach of the Chicano writer Gloria Anzaldúa and in the approach of the Amazonian writer Milton Hatoum in Borderlands/La frontera: The New Mestiza (1987) and Dois Irmãos (2000), respectively. Considering the identity issues, the analysis of the narratives transits/moves/focuses on through the fictional space to highlight the displacements and the migratory flows of the characters as articulators in order to understand the open wounds in border spaces. Therefore, during the research, it was possible to re-signify the frontier as a locus of cultural difference and fragmentation to counteract the idea that frontier places are fixed or function as divisors of cultural systems. To develop this work, I apply comparative and theoretical methods within the culturalist approach as well as the key concepts of Walter Mignolo on the coloniality of knowledge, and Stuart Hall and Homi Bhabha on heterogeneous identities. The denial of the essentialist position, based on the reading of the works, serves as an analytical strategy and understanding of the open wound as the space of the multiplicity in border regions.
28

Resultados de cirurgia monocular de estrabismo de grande angulo sob anestesia peribulbar / Results of monocular surgery of large angle strabismus under peribulbar anesthesia

Millan, Tatiana, 1977- 30 May 2007 (has links)
Orientador: Keila Miriam Monteiro de Carvalho / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Ciencias Medicas / Made available in DSpace on 2018-08-08T19:40:07Z (GMT). No. of bitstreams: 1 Millan_Tatiana_M.pdf: 2201742 bytes, checksum: 9fbc6126d8358be88ca29d8f5d863b72 (MD5) Previous issue date: 2007 / Resumo: Objetivo: Avaliar os resultados da cirurgia monocular na correção de estrabismos horizontais de grande ângulo sob anestesia peribulbar. Métodos: Foram avaliados 92 pacientes submetidos à cirurgia monocular de estrabismo horizontal de grande ângulo (ângulo igual ou superior a 40 dioptrias prismáticas - DP) sob anestesia peribulbar no Hospital das Clínicas/UNICAMP. Os pacientes foram divididos em dois grupos: grupo 1 ¿ esotropias e grupo 2 ¿ exotropias. A cirurgia constava de retrocesso e ressecção dos retos horizontais no olho não dominante. O seguimento pós-operatório foi de 6 meses, quando foram avaliados o desvio residual e a movimentação ocular. Foi considerado como sucesso cirúrgico um desvio residual de até 15 DP. Em casos de desvios maiores que 15 DP, um segundo procedimento era indicado. Resultados: Em todos os pacientes com desvio de até 60 DP foi alcançado sucesso cirúrgico. Nos pacientes com desvio de 65 DP, a cirurgia teve sucesso em 1 de 3 pacientes do grupo 1 e em 5 de 9 pacientes do grupo 2 . Em desvios superiores a 65 DP, todos apresentaram desvios residuais maiores que 15 DP. Destes, 13 pacientes se submeteram a um segundo procedimento e, em todos, houve sucesso cirúrgico. A Análise da Curva ROC mostrou o ponto de corte do desvio pré-operatório para obter sucesso cirúrgico, que foi de 62,5 DP. Nenhum paciente apresentou limitação importante da movimentação ocular. Não houve complicações cirúrgicas ou anestésicas. Conclusões: A cirurgia monocular pode ser uma opção para correção de estrabismos horizontais de grande ângulo, sob anestesia peribulbar, até desvios entre 60 e 65 DP. Acima de 65 DP, a cirurgia monocular não foi suficiente para se obter sucesso pós-operatório / Abstract: Purpose: Evaluate the results of monocular surgery for large-angle horizontal strabismus under peribulbar anesthesia. Methods: Ninety-two patients submitted to monocular surgery under peribulbar anesthesia for large-angle horizontal strabismus (angle of 40 prism dioptre or greater) in Clinical Hospital of State University of Campinas were evaluated. The patients were divided into group 1 ¿ esotropias and group 2 - exotropias. The surgery consisted of recession and resection procedures of the horizontal rectus. The postoperative follow-up was of 6 months, when it was evaluated the resisual deviation and the ocular movement. A residual deviation until 15 PD was considered a successful result. In cases of residual deviation over 15 PD, a second procedure was indicated. Results: In all patients until 60 PD preoperative deviations, successful surgery results were achieved. In the patients with 65 PD preoperative deviations, successful surgery results were obtained in 1 of 3 patients in group 1 and in 5 of 9 patients in group 2. All patients with deviations over 65 PD presented residual deviation over 15 PD. Thirteen patients were submitted to a second procedure. Successful results were obtained in all of them. The ROC Curve Analysis showed the cut point to get a successful surgery result: 62,5 PD. No patient presented important limitation of the ocular movement. There were no complications from surgery or anesthesia. Conclusions: The monocular surgery can be an alternative for horizontal large-angle strabismus under peribulbar anesthesia until deviations between 60 and 65 PD. In the deviations over 65 PD, the monocular surgery did not achieve successful results / Mestrado / Oftalmologia / Mestre em Ciências Médicas
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Palavras e disparates em Borges e Ramón, sobre Historia universal de la infamia e Doña Juana la Loca, Superhistoria / Words and follies in Borges and Ramón, on A Universal History of infamy and Joanna the Mad, Superhistory

Grotto, Livia, 1981- 26 April 2013 (has links)
Orientador: Miriam Viviana Garate / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Estudos da Linguagem / Made available in DSpace on 2018-08-22T21:55:35Z (GMT). No. of bitstreams: 1 Grotto_Livia_D.pdf: 6689770 bytes, checksum: 731fffd3a8d39693d505e29d308aa587 (MD5) Previous issue date: 2013 / Resumo: Este trabalho de doutorado sobre os livros História universal da infâmia de Jorge Luis Borges e Doña Juana la Loca, Superhistoria de Ramon Gomez de la Serna divide-se em duas partes. A primeira, "Borges e Ramon nas revistas literarias espanholas e argentinas, 1919- 1949", contextualiza a relacao desses dois escritores, sobretudo atraves dos periodicos com os quais colaboraram de 1919 a 1949. A segunda parte compreende tres capitulos, destinados a comparar os livros História universal e Doña Juana. O primeiro deles, "Os percursos da voz, um escritor inexperiente e um super-escritor", parte dos prologos desses livros para abordar a construcao da voz dos narradores, observando as suas implicacoes na imagem dos autores implicitos. "Palavras e disparates, sobre as criaturas infames e super-historicas", segundo capitulo, considera os autores implicitos na sua relacao com os personagens de ficcao. O terceiro capitulo, "A epistemologia de Historia universal e a Superhistoria, ciencia literaria", busca aprofundar os sentidos de "Historia universal" e de "Super-historia" que aparecem nos titulos dos livros, a partir de um corte sincronico que esboca as discussoes criticas e epistemologicas que envolveram o campo da Historia no inicio do seculo XX. O ultimo texto deste trabalho intitula-se "Emblemas do cristal em Borges e Ramon". A maneira de um epilogo, retraca o projeto inicial deste estudo, baseado na conferencia-ensaio de Italo Calvino, "Exatidao" (Seis propostas para o próximo milênio) / Abstract: This doctoral thesis on Jorge Luis Borges' A Universal History of Infamy and Ramon Gomez de la Serna's Doña Juana la Loca, Superhistoria is divided into two parts. The first one entitled "Borges and Ramon in the literary Spanish and Argentine magazines, 1919-1949" discusses in its proper context the relationship between these two authors, especially through the periodical magazines where both collaborated from 1919 to 1949. The second part includes three chapters that compare the books A Universal History and Doña Juana. The first one, "The distances of the voice, an inexpert writer and a superwriter ", departs from the prologues of both books in order to approach the construction of the narrator's voice, observing their implications in the image of implicit authors. "Words and follies, on the infamous and super historical creatures" considers both implicit writers in their relation with fictional characters. The third chapter entitled "The epistemology of Universal History and the Superhistory, literary science" aims to deepen the sense of "Universal History" and "Superhistory" present in the titles of the books, from a synchronous cut that outlines critical and epistemological discussions that involved the field of History in the beginning of the 20th century. Finally, the epilogue of this work, "Emblems of the crystal in Borges and Ramon", returns to the initial goal of this thesis, based on Italo Calvino's conference called "Exactitude" (Six Memos for the Next Millennium) / Doutorado / Literatura Geral e Comparada / Doutora em Teoria e História Literária
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Modélisation du comportement mécanique "post-trempe", après oxydation à haute température, des gaines de combustible des réacteurs à eau pressurisée / Modeling of mechanical behavior of quenched zirconium-based nuclear fuel claddings, after a high temperature oxidation

Cabrera Salcedo, Andrea 14 February 2012 (has links)
Le comportement des assemblages combustibles des Réacteurs Nucléaires à Eau Pressurisée (REP) doit être évalué en conditions de fonctionnement ainsi qu'en conditions accidentelles. Pendant la 2ème phase du scénario dit « d'Accident de Perte de Réfrigérant Primaire (APRP) », les gaines tubulaires des crayons combustibles en alliages de Zirconium subissent une oxydation à haute température (jusqu'à 1200°C), à partir de la face externe de la gaine, puis une trempe à l'eau lors du renoyage final du cœur du réacteur accidenté.Après oxydation et trempe, la gaine comporte schématiquement trois couches : une première couche extérieure de zircone très riche en oxygène (ZrO2) fragile à basse température, une deuxième couche de phase alpha stabilisée par l'oxygène (alpha(O)) elle aussi fragile, et une troisième couche interne de phase dite « ex-beta » qui est la seule à pouvoir garder une certaine ductilité à basse température. Cependant, en cas de prise d'hydrogène due à la corrosion en service et/ou pendant le transitoire, l'hydrogène a tendance à se concentrer dans cette couche interne en induisant une fragilisation supplémentaire.A l'issue d'un transitoire APRP et afin de caractériser le comportement résiduel de la gaine, les Essais de Compression d'Anneaux (ou Ring Compression Tests- RCT) sont utilisés pour évaluer les propriétés mécaniques « post trempe » de la gaine car ils sont simples à mettre en œuvre et également peu consommateurs de matière, ce qui est un atout pour d'éventuels essais comparatifs sur matériaux irradiés. Malheureusement, les courbes de force-déplacement ainsi obtenues, bien que très reproductibles, ont une évolution complexe, et sont sujettes à des interprétations diverses.Dans cette thèse, nous proposons un scénario original de rupture des différentes couches de la gaine au cours d'un essai de compression d'anneaux et la modélisation associée. Cette approche intègre à la fois, l'évaluation des contraintes d'origine thermique résultant de la trempe après oxydation à haute température, l'influence de la variation de la teneur en oxygène dans les différentes couches sur leurs lois de comportement respectives, et l'endommagement progressif des différentes couches au cours de l'essai. Le scénario proposé s'appuie sur des essais interrompus, des observations fines des couches de zircone et d'alpha(O), des essais sur anneaux « monocouche ex-beta », et des lois de comportement obtenues sur matériaux modèles.La modélisation EF obtenue rend bien compte des multiples incidents relevés sur les courbes de compression. Le scénario auquel nous aboutissons devrait permettre de lever les interrogations sur les modes de dépouillement macroscopiques de ces essais.Cette étude propose finalement une évaluation préliminaire de l'impact de l'hydrogène (issu de la corrosion en service) sur le comportement mécanique post oxydation/trempe. / During the second stage of Loss Of Coolant Accident (LOCA) in Pressurized Water Reactors (PWR) zirconium-based fuel claddings undergo a high temperature oxidation (up to 1200°C), then a water quench. After a single-side steam oxidation followed by a direct quench, the cladding is composed of three layers: an oxide (Zirconia) outer layer (formed at HT), always brittle at Room Temperature (RT), an intermediate oxygen stabilized alpha layer, always brittle at RT, called alpha(O), and an inner "prior-beta" layer, which is the only layer able to keep some significant Post Quench (PQ) ductility at RT. However, hydrogen absorbed because of service exposure or during the LOCA transient, concentrates in this layer and may leads to its embrittlement.To estimate the PQ mechanical properties of these materials, Ring Compression Tests (RCT) are widely used because of their simplicity. Small sample size makes RCTs advantageous when a comparison with irradiated samples is required. Despite their good reproducibility, these tests are difficult to interpret as they often present two or more load drops on the engineering load-displacement curve. Laboratories disagree about their interpretation.This study proposes an original fracture scenario for a stratified PQ cladding tested by RCT, and its associated FE model. Strong oxygen content gradient effect on layers mechanical properties is taken into account in the model. PQ thermal stresses resulting from water quench of HT oxidized cladding are investigated, as well as progressive damage of three layers during an RCT. The proposed scenario is based on interrupted RCT analysis, post- RCT sample's outer layers observation for damage evaluation, RCTs of prior-beta single-layer rings, and mechanical behavior of especially chemically adjusted samples.The force displacement curves appearance is correctly reproduced using the obtained FE model. The proposed fracture scenario elucidates RCTs of quenched zirconium-based nuclear fuel claddings (after a high temperature oxidation) macroscopic interpretation.Finally, this study presents a preliminary evaluation of the impact of hydrogen on the oxidized cladding's mechanical behavior.

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