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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.
441

Conscious of Her Own Power: Hester Piozzi's Character Creation in Anecdotes of the Late Samuel Johnson LL.D., During the Last Twenty Years of His Life

Weakley, Anne 22 April 2013 (has links)
This project highlights aspects of Hester Piozzi’s approach to biography in Anecdotes of the Late Samuel Johnson LL. D. During the Last Twenty Years of His Life in order to analyze her use of accumulated cultural and social capital. I highlight similarities between Anecdotes and Samuel Johnson’s model for biography given in Rambler #60 and show how Piozzi adheres to his advice as she characterizes Johnson as a pious genius, intolerantly opinionated, and self-indulgent, yet unwilling to accept those qualities in others. I analyze how her editorial choices characterize her as a reliable source of information and a blameless victim of Johnson’s need for attention. This study proves Anecdotes and the corresponding entries in Thraliana are important because her deliberate revisioning of her history speaks to her ability to manipulate social expectations in order to revive her literary career and actively contribute to eighteenth-century British economy, culture, and society.
442

[en] USING FINITE ELEMENT MODEL IN THE DEVELOPMENT OF CUTTING MATERIAL MODELS / [pt] UTILIZAÇÃO DO MÉTODO DOS ELEMENTOS FINITOS NO DESENVOLVIMENTO DE MODELOS DE CORTE DE MATERIAL

CARLOS FERNANDO COGOLLO APONTE 10 June 2019 (has links)
[pt] Entre os vários processos envolvidos na produção de petróleo e gás, o processo de perfuração tem recebido grande atenção recentemente. Pesquisas estão sendo direcionadas para este tema com o objetivo de melhorar o desempenho das brocas de perfuração. Assim, o interesse da indústria do petróleo é aumentar a taxa de penetração, reduzir o tempo de manobras, aumentar a vida útil das brocas e consequentemente reduzir gastos durante o processo de perfuração. Para alcançar estes objetivos, tradicionalmente, são empregados métodos de otimização de perfuração baseados em energia mecânica específica. Estes métodos utilizam como dados de entrada o peso sobre a broca, taxa de penetração, torque e resistência à compressão da rocha. Os métodos de otimização de perfuração ainda apresentam algumas dificuldades, tais como: relacionar energia mecânica específica com resistência à compressão simples e os métodos dependem de dados de perfuração de poços, como listados acima. Este trabalho tem como objetivo apresentar um estudo alternativo do processo de corte em rocha baseado em simulação numérica, especificamente utilizando um programa comercial de elementos finitos chamado Abaqus. A primeira parte do trabalhou consistiu no desenvolvimento de modelos de corte em metais baseado na lei de plasticidade de Johnson-Cook. A motivação na escolha destes modelos foi a grande quantidade de trabalhos encontrados na literatura que tratam do processo de usinagem em metais. Posteriormente, a segunda parte do trabalho, que trata do corte em rocha, foi conduzida. Modelos tridimensionais de ensaios de single cutter foram elaborados e simulados utilizando a lei de plasticidade de Drucker-Prager, adequada para rochas, que considera o efeito da pressão de confinamento. / [en] Among the various processes involved in producing oil and gas, the drilling process has received great attention recently. Research is being directed to this issue in order to improve the performance of drill bits. Thus, the interest of the oil industry is to increase the penetration rate, reduce the time of switching, extending the life of drills and consequently reduce spending during the drilling process. To achieve these goals are traditionally used for drilling optimization methods based on mechanical specific energy. These methods use as input the weight on the drill penetration rate, torque and compressive strength of rock. The drilling optimization methods still present some difficulties, such as mechanical specific energy relationship with compressive strength and the methods depend on data-drilling, as listed above. This dissertation aims to present a study of alternative rock cutting process based on numerical simulation, specifically using a commercial finite element program called Abaqus. The first part of the work was the development of models of metal cutting based on the plasticity law of Johnson-Cook. The motivation in choosing these models was the large number of studies in the literature dealing with the machining process in metals. Subsequently, the second part of the work, which is cut in rock, was conducted. Three-dimensional models of single cutter tests were designed and simulated using the plasticity law of Drucker-Prager, suitable for rocks, which considers the effect of confining pressure.
443

Escala de Intelig?ncia Wechsler para crian?as e Bateria de Habilidades Cognitivas Woodcock Johnson-III: compara??o de instrumentos / The Wechsler Intelligence Scale for children and Battery of Cognitive Habilities Test Woodcock-Johnson: instruments?s comparison

Chiodi, Marcelo Gulini 14 December 2007 (has links)
Made available in DSpace on 2016-04-04T18:27:38Z (GMT). No. of bitstreams: 1 Marcelo Gulini Chiodi.pdf: 363388 bytes, checksum: 0578a0c625e8841b1da092c135b88eb8 (MD5) Previous issue date: 2007-12-14 / Pontif?cia Universidade Cat?lica de Campinas / The study of intellectual evaluation has shown great diversity through out the time. Currently, the theory recognized as the most extensive to explain the mental functioning is the C-H-C (Cattell-Horn-Carroll). Among the tests internationally availables, the only one that meets this proposal is the theoretical battery Woodcock Johnson III (WJ - IIII). Accordingly, the objective of this study was to verify the convergence validity battery of Cognitives Abilities Woodcock-Johnson III, comparing it with the Wechsler Intelligence Scale for Children - WISC-III, already validated for our reality. The sample was composed of 30 students from public school of Primary and Secondary Education, being 15 men and 15 women aged between 13 and 15 years. It was applied to the participants, with parents permission, the two sets of Cognitive Abilities WJ-III and WISC-III. The results were analyzed according to the Pearson correlation and it was performed the Analysis of Variance between gender and age for each instrument. The results pointed to a significant correlation between the total score of Woodcock and the total score in the WISC of 0,865, between Woodcock and the scale implementation 0,766 and the scale verbal 0,843. As for the Analysis of Variance, in the instrument WISC-III there was no significant difference in age and in subtestes Complete Figures and Cubes Sex x Age to the subtest vocabulary. In addition, for the instrument WJ-III there were differences of Sex X Age only for subtest Verbal Understanding. The Battery Woodcock Johnson III is considered the most complete in order to allow the evaluation of different differents cognitive abilities of the model C-HC, and therefore, according to the presents results, the battery WJ-III can be used in Brazil to replace the WISC - III. / O estudo da avalia??o intelectual tem apresentado grande diversidade atrav?s dos tempos. Atualmente, a teoria reconhecida como sendo a mais ampla para explicar o funcionamento mental ? a C-H-C (Cattell-Horn-Carroll) . Dentre os testes dispon?veis internacionalmente, o ?nico que atende a esta proposta te?rica ? a Bateria Woodcock-Johnson III (WJ-IIII). Neste sentido, o objetivo deste trabalho foi verificar a validade convergente da Bateria de Habilidades Cognitivas Woodcock Johnson-III, comparando-a com a Escala Wechsler de Intelig?ncia para Crian?as WISC- III, que j? apresenta evidencias de validada para a nossa realidade. A amostra foi composta por 30 estudantes de escola p?blica do Ensino Fundamental e M?dio, sendo 15 homens e 15 mulheres com idades entre 13 e 15 anos. Foram aplicadas nos participantes, com a autoriza??o dos pais, as duas baterias de Habilidades Cognitivas WJ-III e WISC-III. Os resultados obtidos foram analisadas segundo a correla??o de Pearson e foi realizada a An?lise de Vari?ncia entre sexo e idade para cada instrumento. Os resultados apontaram para uma correla??o significativa entre a pontua??o total do Woodcock e a pontua??o total no WISC de 0,865, entre o Woodcock e a escala execu??o 0,766 e com a escala verbal 0,843. Com rela??o a An?lise de Vari?ncia, no instrumento WISC-III houve diferen?a significativa da Idade nos subtestes Completar Figuras e Cubos e de Sexo X Idade para o subteste Vocabul?rio. J? com o instrumento WJ-III houve diferen?as de Sexo X Idade somente para o subteste Compreens?o Verbal. Tais dados nos indicam que a Bateria de Habilidades Cognitivas Woodcock-Johnson- III- WJ-III permite uma avalia??o e um diagn?stico mais detalhado das v?rias habilidades cognitivas, podendo enriquecer ainda mais as possibilidades de instrumentos para avalia??o intelectual.
444

Environmental Justice in Natural Disaster Mitigation Policy and Planning: a Case Study of Flood Risk Management in Johnson Creek, Portland, Oregon

Cho, Seong Yun 26 July 2018 (has links)
This study aims to explore the possibility of environmental justice as social consensus and an institutional framework to reduce socioeconomic differences in natural disaster vulnerability through a case study of flood risk management in Johnson Creek, Portland, Oregon. First, by analyzing institutions, policies, and currently ongoing flood mitigation projects, this study investigates how federal and local governments are addressing and responding to current flood problems. Second, through flood expert surveys and GIS spatial analysis, this study examines various factors that contribute to communities' susceptibility to flood risks, and whether there exist spatial differences between physically and socioeconomically vulnerable communities within the Johnson Creek area. Lastly, this study conducted comparative analysis of perceptions using Q-methodology to explore the diverse range of meanings and understandings that flood experts and urban practitioners construct in relation to the dilemmas of environmental justice in flood mitigation practice. The findings of this study indicate that institutional blind spots and barriers in natural disaster mitigation policy and planning can be generated by flood experts' and urban practitioners' different understandings of vulnerability, different interpretations of human rights, and different perspectives on the extent of institutional responsibility to assist socioeconomically vulnerable populations.
445

Responsabilidade social como estratégia corporativa: o caso da Johnson & Johnson

Rosenchan, Tatiana 29 September 1998 (has links)
Made available in DSpace on 2010-04-20T20:21:00Z (GMT). No. of bitstreams: 0 Previous issue date: 1998-09-29T00:00:00Z / Trata da reorganização do espaço público/civil através de novos posicionamentos dos diferentes agentes da realidade socioeconômicas. Debate a necessidade da conscientização das possibilidades de sinergia na atuação conjunta entre os setores público, privado e terceiro setor. Enfoca, através de ilustrações e estudo de caso, o importante e estratégico papel que a empresa assume como protagonista social. Analisa impactos e conseqüências dessa atuação.
446

Development of a numerical model of single particle impact with adhesion for simulation of the Cold Spray process / Développement d'un modèle numérique d'impact à une seule particule avec adhérence pour la simulation du processus de pulvérisation à froid

Profizi, Paul 20 September 2016 (has links)
Dans le cadre du procédé de revêtement de surface Cold Spray, un modèle numérique d’impact de particule sur substrat à haute vitesse est créé, ainsi qu’une nouvelle interaction adhésive, dans le logiciel de dynamique explicite du CEA Europlexus. Le modèle utilise des Éléments Finis et la méthode sans maillage SPH (Smoothed Particle Hydrodynamics) avec la loi matériau de Johnson-Cook, couramment utilisée pour modéliser les métaux à des vitesses de déformation élevées et prenant en compte le durcissement plastique, le durcissement en vitesse de déformation, et l’assouplissement thermique. L’interaction adhésive est basée sur les modèles de zone cohésive de Dugdale-Barenblatt et Griffith, avec une limite sur la contrainte cohésive et la rupture de l’adhésion dictée par l’énergie dissipée. L’étude de cette interaction dans le cas des corps déformables à haute vitesse de déformation montre que le type de modèle cohésif utilisé impacte directement et de façon très prononcée les résultats du calcul. L’interaction adhésive est ensuite liée à un mécanisme physique connu pour être la raison majeure de l’adhésion entre métaux lors du procédé Cold Spray : l’instabilité en cisaillement à l’interface de contact (présente dans la simulation grâce à une loi d’endommagement). Pour ce faire, un critère d’activation de l’adhésion est créé, basé sur une chute de la valeur locale de limite élastique du matériau. Ce critère permet de retrouver le phénomène de vitesse critique nécessaire pour l’adhésion de la particule lors du procédé. Un critère de rupture de l’adhésion supplémentaire est ajouté, basé sur la valeur de l’endommagement dans les éléments collés, et permet de retrouver le phénomène de vitesse maximale pour l’adhésion de la particule. Le modèle complet, construit sur des principes physiques, est ainsi capable de simuler le phénomène d’adhésion Cold Spray. Des tests de dureté et images EBSD sont aussi présentés et comparés aux résultats numériques. / In the context of the Cold Spray process, a numerical model of a single particle impact is developed. The point of interest is the adhesion of the particle to the substrate, thus an adhesive interaction model is also created. The impact model uses the Smooth Particle Hydrodynamics and/or the Finite Elements methods, with a Johnson-Cook material law, commonly used for metals at high strain rates, which takes into account strain hardening, strain rate hardening and thermal softening. The adhesive interaction is a Griffith and Dugdale-Barenblatt cohesive model with energy dissipation and a limit on the cohesive stress. Using this model it is shown that in the case of fast dynamics and deformable bodies, not only the adhesion parameters but also the type of model has an influence on the results. The adhesion model is also, contrary to previous works, linked with an actual physical mechanism known to induce adhesion in Cold Spray: a shear stress instability at the interface. This is done by adding an activation criterion to the cohesive model. This criterion is defined as a local drop in yield strength on either element in contact. Only when this criterion is locally met are the cohesive stresses applied and cohesive energy dissipated. The result is the apparition of a critical velocity, under which adhesion cannot occur due to either not enough initial kinetic energy to create an instability at the interface, or not enough adhesive surface created to keep the particle from rebounding. For the model to localize and undergo shear banding/shear instability, a damage value is added to the material law. An erosion criterion is then implemented in the cohesive model to remove the cohesive stresses from highly damaged parts of the adhesive surface. This results at high impact speeds in a maximal velocity above which the interfacial material is too damaged to sustain adhesion and prevent the particle from rebounding. A deposition behavior similar to the Cold Spray process is then observed, with a range of low velocities without any adhesion of the particle, then a critical speed initiating a velocity range of adhesion of the particle, and finally a maximum speed above which the interface is too damaged to sustain the adhesion. A set of experimental observations is also carried out to better understand the actual microstructural dynamics and changes at the interface of 1 mm copper particles impacted on copper. The results are compared to simulations and the use of the macroscopic Johnson-Cook law at a microscopic level is validated.
447

Propagation d'ondes acoustiques dans les milieux poreux fractals / Acoustic propagation in fractal porous media

Berbiche, Amine 15 December 2016 (has links)
La méthode de minimisation de l'intégrale d'action (principe variationnel) permet d’obtenir les équations de propagation des ondes. Cette méthode a été généralisée aux milieux poreux de dimensions fractales, pour étudier la propagation acoustique dans le domaine temporel, en se basant sur le modèle du fluide équivalent. L'équation obtenue réécrite dans le domaine fréquentiel représente une généralisation de l'équation d'Helmholtz. Dans le cadre du modèle d'Allard-Johnson, l'équation de propagation a été résolue de manière analytique dans le domaine temporel, dans les régimes des hautes et des basses fréquences. La résolution a été faite par la méthode de la transformée de Laplace, et a porté sur un milieu poreux semi-infini. Il a été trouvé que la vitesse de propagation dépend de la dimension fractale. Pour un matériau poreux fractal d'épaisseur finie qui reçoit une onde acoustique en incidence normale, les conditions d’Euler ont été utilisées pour déterminer les champs réfléchi et transmis. La résolution du problème direct a été faite dans le domaine temporel, par la méthode de la transformée de Laplace, et par l’usage des fonctions de Mittag-Leffler. Le problème inverse a été résolu par la méthode de minimisation aux sens des moindres carrés. Des tests ont été effectués avec succès sur des données expérimentales, en utilisant des programmes numériques développés à partir du formalisme établi dans cette thèse. La résolution du problème inverse a permis de retrouver les paramètres acoustiques de mousses poreuses, dans les régimes des hautes et des basses fréquences. / The action integral minimization method (variational principle) provides the wave propagation equations. This method has been generalized to fractal dimensional porous media to study the acoustic propagation in the time domain, based on the equivalent fluid model. The resulting equation rewritten in the frequency domain represents a generalization for the Helmholtz equation. As part of the Allard-Johnson model, the propagation equation was solved analytically in the time domain, for both high and low frequencies fields. The resolution was made by the method of the Laplace transform, and focused on a semi-infinite porous medium. It was found that the wave velocity depends on the fractal dimension.For a fractal porous material of finite thickness which receives an acoustic wave at normal incidence, the Euler conditions were used to determine the reflected and transmitted fields. The resolution of the direct problem was made in the time domain by the method of the Laplace transform, and through the use of the Mittag-Leffler functions. The inverse problem was solved by the method of minimizing the least squares sense. Tests have been performed successfully on experimental data; programs written from the formalism developed in this work have allowed finding the acoustic parameters of porous foams, in the fields of high and low frequencies.
448

Out of Scandinavia. Littérature d'émigration nordique : 1920-1930 / Out of Scandinavia. Nordic emigration literature : 1920s-1930s

Heide, Marina 20 November 2017 (has links)
Dans les années 1920 et 1930, le canon littéraire scandinave semble s’écrire hors des frontières du Nord. De nombreux écrivains aujourd’hui reconnus comme des classiques, tels que Karen Blixen, Eyvind Johnson, Harry Martinson et Aksel Sandemose, font non seulement le choix de quitter la Scandinavie, mais encore de raconter l’ailleurs. Que signifie et implique la délocalisation du champ scandinave de l’époque ? Quels liens peut-on établir entre espace et écriture ? Quelles représentations du paysage en ressortent ? Quelles formes d’identités trouvent leur accomplissement par ce biais ? L’étude de quatre romans permet de tenter de comprendre les mécanismes du phénomène d’émigration littéraire que le Danemark, la Suède et la Norvège ont connu au début du XXème siècle. Il ne s’agit pas d’un mouvement, encore moins d’une école, mais d’une tendance qu’ont eue les artistes scandinaves à se situer « Out of Scandinavia » pour façonner l’identité littéraire nordique au seuil de la modernité. / In the 1920s and 1930s, the Scandinavian literary canon seems to be written outside the borders of the North. Many writers that we acknowledge today as classic authors such as Karen Blixen (Isak Dinesen), Eyvind Johnson, Harry Martinson and Aksel Sandemose leave the Scandinavian peninsula and narrate the new horizons. What does that kind of relocation of the Scandinavian literary scene mean and imply? How can we link the notion of space to literary writing? How are the landscapes depicted? What kind of identities emerges from this perspective? This work takes focus on four novels and aims to understand the mechanism of the Nordic literary emigration that occurred in Denmark, Sweden and Norway in the beginning of the 20th century. It is not an artistic movement nor a school, but a tendency for Scandinavian writers to take an “Out of Scandinavia” point of view, in order to shape the identity of Nordic literature on the brink of modernity.
449

Detekce kolize objektů v 3D prostoru / Collision detection in 3D space

Grulich, Jan January 2016 (has links)
Práce se zabývá detekcí kolizí v 3D simulačním prostoru. V první části jsou popsány nejpoužívanější algoritmy pro detekci, stejně jako některé knihovny hotových řešení. Druhá část práce obsahuje popis testovacího softwaru vytvořeného na základě knihovny OpenGL, včetně popisu důležitých částí. V poslední části práce jsou také prezentovány výsledky testování a porovnání vybraných algoritmů na vytvořených testovacích úlohách.
450

The Evolution of the Improvisational Vocabulary of Marc Johnson

Helsley, Jack 05 1900 (has links)
This study examines the evolution of the improvisational vocabulary utilized by bassist Marc Johnson over the course of his career. Through interviews and musical analysis the study contextualizes Johnson’s musical influences, considers how they shaped his development, and examines his role in the legacy of the stylistic lineage established by Scott LaFaro with the Bill Evans Trio. A survey of literature concerning Johnson, Scott LaFaro and Eddie Gomez is included, as well as a discussion of the impact of apprenticeship on Johnson’s career. The study illuminates aspects of Johnson’s current vocabulary and how he has synthesized influences to create a distinctive vocabulary, not derivative of Scott LaFaro or Eddie Gomez, but incorporating elements of their style in the composition of his own voice.

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