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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.
51

Marvels of the Invisible

Molberg, Jenny, 1985- 05 1900 (has links)
This dissertation is comprised of a collection of poems preceded by a critical preface. The preface considers the consumed animal body as a metaphor in contemporary American poetry, specifically in the works of Galway Kinnell, Li Young Lee, and Brigit Pegeen Kelly. The consumption of the mute creature allows the poet to identify the human self in the animal other, and serves as a metaphor for our continuity with the natural world. I revise Owen Barfield’s notion of “original participation,” positing that through imaginative participation, the poet and the reader can identify the animal within the self, and thus approach a fuller understanding of both the self and the outside world. We identify the animal other within the human self, and in of this act of relating, we are able to temporarily transgress the boundaries of the individual self to create art that expresses continuity with the outside world. This argument brings about a discussion of text as an act of consumption, and the way and which this can symbolize the ways in which the self is altered through the act of reading. The book-length collection of poems, entitled Marvels of the Invisible, won Tupelo Press’s 2014 Berkshire prize for a first or second book of poetry. The poems look to sources like 17th and 18th century scientific letters, modern and contemporary art, and recent studies in biological phenomena in order to parse the intersection between personal experience and the outside world. The title of the collection points to the conceptual interests of the book: through the lens of scientific phenomena, memory, and personal history, one begins to see that what seems very small (the ant under a microscope, a Russian nesting doll, two people on horseback) are, in fact, individual offerings that articulate one’s place in the cosmos. The collective voice I advocate in the critical preface appears in these poems, especially “Echolocation,” “My Name in Sleep,” “Civilization,” and “Narrative,” all of which make use of the animal-as-metaphor. This collective voice is particularly female, and deals with motherhood, loss, and childhood experience. Poetry, as part-myth, longs to transgress the felt boundaries of the self; it must see that self as inextricably dependent on the natural world.
52

The politics of female friendship in contemporary speculative fiction

Colombo Machado, Gabriella 11 1900 (has links)
Ce projet examine comment la politique et l’amitié sont actualisées dans la fiction spéculative du XXIe siècle à travers différents médias. Cette thèse aborde la manière dont ces relations interpersonnelles affectent la sphère sociale et le statu quo des mondes fictifs à l’étude. Pour orienter la discussion, j’utilise le concept d’autonomie relationnelle qui reconnaît l’interdépendance des individus autonomes et de la communauté en général et l’éthique du care qui environne la moralité comme étant relationnelle et contextualisée. L’utilisation conjointe de ces deux cadres me permet de discuter de la façon dont les amitiés sont propices à la participation politique. Le premier chapitre présente une discussion globale de The Handmaid’s Tale (1985) de Margaret Atwood et notamment de son influence au sein du genre de la fiction spéculative féministe. Ensuite, dans une première section, je me concentre sur les notions d’autonomie par rapport à l’adaptation graphique du roman d’Atwood par Renée Nault (2019), que je compare avec la bande dessinée Bitch Planet de Kelly Sue DeConnick et Valentine de Landro (2013-2017). Dans une seconde section, je me concentre sur l’éthique du care en tant que processus pouvant favoriser des amitiés empreintes d’implications politiques en analysant l’adaptation télévisée de The Handmaid’s Tale, produite par Hulu, et la série Orphan Black, produite par BBC America. La fiction spéculative permet d’expérimenter librement avec différentes idées politiques et de comprendre comment la société pourrait réagir dans des scénarios extrêmes. Ces expériences de pensée reflètent nos propres luttes et lacunes politiques et pourraient ultimement indiquer de meilleures façons de résoudre les problèmes actuels. / This project examines how politics and friendship are actualized in speculative fiction across different media in the twenty-first century. This thesis discusses how these interpersonal relationships affect the social sphere and the status quo of the fictional worlds in question. To guide the discussion, I use the concept of relational autonomy, which recognizes the interconnectedness of both autonomous individuals and the community at large, and ethics of care, which understands morality as relational and contextualized. I use these two frameworks in tandem to discuss how friendships are conducive to political participation. The first chapter presents an overarching discussion of Margaret Atwood's The Handmaid's Tale (1985) in its legacy to the feminist speculative fiction genre. Following, in the first section, I focus on notions of autonomy in relation to Renée Nault's graphic novel adaptation of Atwood’s novel (2019) and contrast it with Kelly Sue DeConnick and Valentine de Landro’s comic Bitch Planet (2013-2017). In the second section, I focus on the ethics of care as a process that can foster friendships with political implications by analyzing Hulu's TV adaptation of The Handmaid's Tale and BBC America's Orphan Black. SF offers the freedom to test different political ideas and to understand how society might react in extreme scenarios. These thought experiments reflect our own political struggles and shortcomings; ultimately, they might point at better ways to solve current problems.
53

The Virtue of Penance in the United States, 1955-1975

Morrow, Maria Christina January 2013 (has links)
No description available.
54

Réalisation en guides d'ondes numériques stables d'un modèle acoustique réaliste pour la simulation en temps-réel d'instruments à vent

Mignot, Rémi 03 December 2009 (has links) (PDF)
Ce travail porte sur la modélisation physique des tubes acoustiques pour la simulation numérique en temps-réel. Le but principal est la synthèse sonore d'instruments à vent, avec un modèle réaliste, une méthode modulaire et une implémentation numérique faible coût. Le modèle acoustique de "Webster-Lokshin", utilisé ici, est un modèle à 1 dimension prenant en compte à la fois la "courbure" du profil et les "pertes visco-thermiques" à la paroi. Pour ce modèle acoustique, une structure de simulation compatible avec l'approche des "Guides d'Ondes" est obtenue : un tube y est représenté par un système bouclé, avec retards, faisant intervenir plusieurs sous-systèmes sans retard interne. Une difficulté est la présence de sous-systèmes de dimension infinie qui se comportent comme des sommes infinies de systèmes du premier ou du second ordre. Dans un premier temps, ils sont approximés par des systèmes de dimension finie, puis leur "représentation d'état" à temps discret est obtenue. Enfin, en utilisant des outils standard de l'automatique, ces représentations nous permettent de faciliter la connexion d'éléments acoustiques et de réduire les coûts de calcul de la simulation numérique. Dans ce travail, l'étude de la stabilité et de la passivité est faite. Pour des cas paticuliers de tubes, un problème survient : même si les relations entrées/sorties du tube sont stables, certains sous-systèmes internes possèdent une infinité de singularités à l'origine d'instabilités internes. Nous présentons une explication de ce phénomène et ceci nous amène à proposer une nouvelle décomposition en sous-systèmes pour lever ce problème.
55

Análise de carteiras em tempo discreto / Discrete time portfolio analysis

Kato, Fernando Hideki 14 April 2004 (has links)
Nesta dissertação, o modelo de seleção de carteiras de Markowitz será estendido com uma análise em tempo discreto e hipóteses mais realísticas. Um produto tensorial finito de densidades Erlang será usado para aproximar a densidade de probabilidade multivariada dos retornos discretos uniperiódicos de ativos dependentes. A Erlang é um caso particular da distribuição Gama. Uma mistura finita pode gerar densidades multimodais não-simétricas e o produto tensorial generaliza este conceito para dimensões maiores. Assumindo que a densidade multivariada foi independente e identicamente distribuída (i.i.d.) no passado, a aproximação pode ser calibrada com dados históricos usando o critério da máxima verossimilhança. Este é um problema de otimização em larga escala, mas com uma estrutura especial. Assumindo que esta densidade multivariada será i.i.d. no futuro, então a densidade dos retornos discretos de uma carteira de ativos com pesos não-negativos será uma mistura finita de densidades Erlang. O risco será calculado com a medida Downside Risk, que é convexa para determinados parâmetros, não é baseada em quantis, não causa a subestimação do risco e torna os problemas de otimização uni e multiperiódico convexos. O retorno discreto é uma variável aleatória multiplicativa ao longo do tempo. A distribuição multiperiódica dos retornos discretos de uma seqüência de T carteiras será uma mistura finita de distribuições Meijer G. Após uma mudança na medida de probabilidade para a composta média, é possível calcular o risco e o retorno, que levará à fronteira eficiente multiperiódica, na qual cada ponto representa uma ou mais seqüências ordenadas de T carteiras. As carteiras de cada seqüência devem ser calculadas do futuro para o presente, mantendo o retorno esperado no nível desejado, o qual pode ser função do tempo. Uma estratégia de alocação dinâmica de ativos é refazer os cálculos a cada período, usando as novas informações disponíveis. Se o horizonte de tempo tender a infinito, então a fronteira eficiente, na medida de probabilidade composta média, tenderá a um único ponto, dado pela carteira de Kelly, qualquer que seja a medida de risco. Para selecionar um dentre vários modelos de otimização de carteira, é necessário comparar seus desempenhos relativos. A fronteira eficiente de cada modelo deve ser traçada em seu respectivo gráfico. Como os pesos dos ativos das carteiras sobre estas curvas são conhecidos, é possível traçar todas as curvas em um mesmo gráfico. Para um dado retorno esperado, as carteiras eficientes dos modelos podem ser calculadas, e os retornos realizados e suas diferenças ao longo de um backtest podem ser comparados. / In this thesis, Markowitz’s portfolio selection model will be extended by means of a discrete time analysis and more realistic hypotheses. A finite tensor product of Erlang densities will be used to approximate the multivariate probability density function of the single-period discrete returns of dependent assets. The Erlang is a particular case of the Gamma distribution. A finite mixture can generate multimodal asymmetric densities and the tensor product generalizes this concept to higher dimensions. Assuming that the multivariate density was independent and identically distributed (i.i.d.) in the past, the approximation can be calibrated with historical data using the maximum likelihood criterion. This is a large-scale optimization problem, but with a special structure. Assuming that this multivariate density will be i.i.d. in the future, then the density of the discrete returns of a portfolio of assets with nonnegative weights will be a finite mixture of Erlang densities. The risk will be calculated with the Downside Risk measure, which is convex for certain parameters, is not based on quantiles, does not cause risk underestimation and makes the single and multiperiod optimization problems convex. The discrete return is a multiplicative random variable along the time. The multiperiod distribution of the discrete returns of a sequence of T portfolios will be a finite mixture of Meijer G distributions. After a change of the distribution to the average compound, it is possible to calculate the risk and the return, which will lead to the multiperiod efficient frontier, where each point represents one or more ordered sequences of T portfolios. The portfolios of each sequence must be calculated from the future to the present, keeping the expected return at the desired level, which can be a function of time. A dynamic asset allocation strategy is to redo the calculations at each period, using new available information. If the time horizon tends to infinite, then the efficient frontier, in the average compound probability measure, will tend to only one point, given by the Kelly’s portfolio, whatever the risk measure is. To select one among several portfolio optimization models, it is necessary to compare their relative performances. The efficient frontier of each model must be plotted in its respective graph. As the weights of the assets of the portfolios on these curves are known, it is possible to plot all curves in the same graph. For a given expected return, the efficient portfolios of the models can be calculated, and the realized returns and their differences along a backtest can be compared.
56

Análise de carteiras em tempo discreto / Discrete time portfolio analysis

Fernando Hideki Kato 14 April 2004 (has links)
Nesta dissertação, o modelo de seleção de carteiras de Markowitz será estendido com uma análise em tempo discreto e hipóteses mais realísticas. Um produto tensorial finito de densidades Erlang será usado para aproximar a densidade de probabilidade multivariada dos retornos discretos uniperiódicos de ativos dependentes. A Erlang é um caso particular da distribuição Gama. Uma mistura finita pode gerar densidades multimodais não-simétricas e o produto tensorial generaliza este conceito para dimensões maiores. Assumindo que a densidade multivariada foi independente e identicamente distribuída (i.i.d.) no passado, a aproximação pode ser calibrada com dados históricos usando o critério da máxima verossimilhança. Este é um problema de otimização em larga escala, mas com uma estrutura especial. Assumindo que esta densidade multivariada será i.i.d. no futuro, então a densidade dos retornos discretos de uma carteira de ativos com pesos não-negativos será uma mistura finita de densidades Erlang. O risco será calculado com a medida Downside Risk, que é convexa para determinados parâmetros, não é baseada em quantis, não causa a subestimação do risco e torna os problemas de otimização uni e multiperiódico convexos. O retorno discreto é uma variável aleatória multiplicativa ao longo do tempo. A distribuição multiperiódica dos retornos discretos de uma seqüência de T carteiras será uma mistura finita de distribuições Meijer G. Após uma mudança na medida de probabilidade para a composta média, é possível calcular o risco e o retorno, que levará à fronteira eficiente multiperiódica, na qual cada ponto representa uma ou mais seqüências ordenadas de T carteiras. As carteiras de cada seqüência devem ser calculadas do futuro para o presente, mantendo o retorno esperado no nível desejado, o qual pode ser função do tempo. Uma estratégia de alocação dinâmica de ativos é refazer os cálculos a cada período, usando as novas informações disponíveis. Se o horizonte de tempo tender a infinito, então a fronteira eficiente, na medida de probabilidade composta média, tenderá a um único ponto, dado pela carteira de Kelly, qualquer que seja a medida de risco. Para selecionar um dentre vários modelos de otimização de carteira, é necessário comparar seus desempenhos relativos. A fronteira eficiente de cada modelo deve ser traçada em seu respectivo gráfico. Como os pesos dos ativos das carteiras sobre estas curvas são conhecidos, é possível traçar todas as curvas em um mesmo gráfico. Para um dado retorno esperado, as carteiras eficientes dos modelos podem ser calculadas, e os retornos realizados e suas diferenças ao longo de um backtest podem ser comparados. / In this thesis, Markowitz’s portfolio selection model will be extended by means of a discrete time analysis and more realistic hypotheses. A finite tensor product of Erlang densities will be used to approximate the multivariate probability density function of the single-period discrete returns of dependent assets. The Erlang is a particular case of the Gamma distribution. A finite mixture can generate multimodal asymmetric densities and the tensor product generalizes this concept to higher dimensions. Assuming that the multivariate density was independent and identically distributed (i.i.d.) in the past, the approximation can be calibrated with historical data using the maximum likelihood criterion. This is a large-scale optimization problem, but with a special structure. Assuming that this multivariate density will be i.i.d. in the future, then the density of the discrete returns of a portfolio of assets with nonnegative weights will be a finite mixture of Erlang densities. The risk will be calculated with the Downside Risk measure, which is convex for certain parameters, is not based on quantiles, does not cause risk underestimation and makes the single and multiperiod optimization problems convex. The discrete return is a multiplicative random variable along the time. The multiperiod distribution of the discrete returns of a sequence of T portfolios will be a finite mixture of Meijer G distributions. After a change of the distribution to the average compound, it is possible to calculate the risk and the return, which will lead to the multiperiod efficient frontier, where each point represents one or more ordered sequences of T portfolios. The portfolios of each sequence must be calculated from the future to the present, keeping the expected return at the desired level, which can be a function of time. A dynamic asset allocation strategy is to redo the calculations at each period, using new available information. If the time horizon tends to infinite, then the efficient frontier, in the average compound probability measure, will tend to only one point, given by the Kelly’s portfolio, whatever the risk measure is. To select one among several portfolio optimization models, it is necessary to compare their relative performances. The efficient frontier of each model must be plotted in its respective graph. As the weights of the assets of the portfolios on these curves are known, it is possible to plot all curves in the same graph. For a given expected return, the efficient portfolios of the models can be calculated, and the realized returns and their differences along a backtest can be compared.

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