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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.
101

Doing Double-Dutch: Womanish Modes of Play as a Pedagogical Resource for Theological Education

Lockhart, Lakisha Renee January 2018 (has links)
Thesis advisor: Thomas H. Groome / In the United States and in the American Academy there is a historical reality much like jump rope. In jump rope there is but one rope, in the case of the U.S. there is one white, western, male Christian narrative-a rope that one jumps in on specific way. This can be very difficult for those that do not identify with or know how to jump this particular rope. Theological education has a unique opportunity to be a prophetic voice in advocating for the addition of a womanist rope in order to do Double-Dutch, together, regardless of difference. This rope is one that embraces a womanist consciousness as is advocates for the agency and identity formation of all, the lifting up and accountability of all persons, the freedom of embodiment and expression in all forms, and remains active and critical of injustice and all systems of oppression. Once this rope is added everyone can begin to engage in womanish modes of play that are embodied aesthetic experiences and cultural expressions that function as a means of knowing, being, and making meaning in this world. When all persons do Double-Dutch together play becomes a tool for learning and teaching religious education across differences. / Thesis (PhD) — Boston College, 2018. / Submitted to: Boston College. Graduate School of Arts and Sciences. / Discipline: Religious Education and Pastoral Ministry.
102

Vibrações localizadas de pares H-H-, D-D- e H-D- em KCl, KBr, KI, RbCl e NaCl / Localized vibrations of pairs H-H-, D-D- e H-D- in KCl, KBr, KI, RbCl and NaCl

Robert, Renê 30 May 1974 (has links)
Os modos vibracionais localizados dos pares H-H-, D-D- e H-D- em KCl, KBr, KI, RbCl e NaCl foram estudados para diversas configurações. As frequências dos modos infravermelho ativos determinados experimentalmente mostram boa concordância com o modelo de dois osciladores harmônicos acoplados. A largura de linha para os diferentes modos nos cristais examinados é discutida. A dependência com a temperatura da largura de linha para os modos transversais T1 e T2 no sistema KCl+ H- H-, indica que o alargamento das mesmas é devida ao \"mecanismo de decomposição\", no qual dois fônons são criados. Estes fônons são devidos ao decaimento do modo localizado em fase num fônon acústico da rede e num fônon localizado fora de fase. Propriedades gerais, como a lei de Ivey e diversas outras particularidades dos halogenetos alcalinos estudados são apresentadas / The localized vibrational modes of H-H-, D-D- and H-D- in KCl, KBr, KI, RbCl and NaCl were studied for different pair configurations. The measured frequencies of the infrared active modes were found to be in good agreement with a model of two coupled harmonic oscillators. The line width for different modes in the salts studied is discussed. The temperature dependence for the transversal modes T1 and T2 of the line width for the H- H- pairs in KCl indicates that the broadening of these lines is due to the \"decomposition mechanism\", that generates two phonons. The generated phonons due to the decay of the localized phonon that corresponds to the out of phase vibration of the H- H- pair. The general properties, as the Ivey law and several particulars of the properties in the alkali-halides studied are presented
103

Velhices urbanas: seguras - sustentáveis - saudáveis / Urban old ages: safe, healthy, sustainable

Cesar, Ana Cristina Satiro de Souza Monteclaro 05 May 2014 (has links)
Os desafios que o crescente aumento da população idosa coloca na estruturaçao urbana nos motivou a elaborar essa dissertação a fim de entender o processo de envelhecimento, as condições de moradia atual dos idosos e as favoráveis técnicas na construção de ambientes facilitadores diante de declínios da capacidade física decorrente do envelhecimento com a finalidade elaborar princípios projetuais apropriados para todas as pessoas. Utilizou-se como base referencias bibliográficas e visitas a conjuntos habitacionais exclusivos para idosos e edifícios com grande volume de moradores idosos no Estado de São Paulo. / The challenges the increasing urban places in structuring motivated us to develop this dissertation in order to understand the aging process, the current housing conditions of the elderly and favorable techniques in building enabling environments face of declines in physical capacity due to aging in order to draw up appropriate projective principles for all people. It was used as a reference base bibliographic and visits to unique housing for elderly and buildings with large amount of elderly residents the State of São Paulo.
104

Estudo espectral das ondas de Alfvén em plasma cilíndrico / Spectral study of Alfvén waves in cylindrical plasma

Shigueoka, Hisataki 11 November 1991 (has links)
Neste trabalho foi estudado o espectro das ondas de MHD ideal em um plasma cilíndrico. Considerando o plasma inomogêneo, o espectro apresenta regiões discretas e contínuas: onda lenta e onda de Alfvén. Os automodos das regiões discretas são as soluções da equação de Hain-Lüst e, nas regiões contínuas, as autofunções apresentam singularidades. Foram determinadas expressões analíticas em termos da função de Bessel que os autovalores da onda de Alfvén apresentam o comportamento discreto. Os modos globais discretos de Alfvén foram calculados usando um equilíbrio da configuração de tokamak, beta < 1, e estes modos apresentam uma pequena contribuição da onda compressional. Foi feita uma análise da propagação da energia da onda por meio do vetor de Poynting e este conhecimento tem a sua importância no problema de aquecimento do plasma por ondas de Alfvén. Foi feita, também, uma análise da polarização das ondas. Foi estudado o espectro da onda devido ao efeito de beta, beta > 1. Esta condição é mais aplicável em problemas de plasma espacial, por exemplo, na fotosfera solar. Foram obtidos, pela primeira vez, os modos discretos de onda lenta, previstos teoricamente. As suas soluções (autofunções e autovalores) possuem também a característica global, aqui denominadas de modos globais discretos da onda lenta. Outro estudo do problema espectral foi realizado para urna configuração de equilíbrio para RFP (\"Reversed Field Pinch\"). Determinou-se, além dos automodos Sturmianos da onda de Alfvén, os automodos anti-Sturmianos da onda lenta. / The spectrum of the ideal MHD waves in cylindrical plasmas has been studied. Assuming non homogeneous plasma, the spectrum presents the discrete and continuum (slow and Alfvén waves) regions. The eigenfunctions of the discrete regions are the solutions of the Hain-Lüst equation. In the continua, the solutions of this equation have singularities. It has been determined analytical expressions for the discrete eigenfunctions. These happen to be the Bessel\'s function and its eigenvalues agree with the numerical calculations. The discrete modes (global modes) of Alfvén waves have been calculated by numerically using the equilibrium configuration of tokamaks, beta < 1, and it was observed that these modes present a small contribution from the compressional waves. An analysis of the energy propagation was done using the Poynting vector. This has its importance in the problem of plasma heating by Alfvén waves. Its polarization was also studied. The effect of beta, through values greater than 1, was also studied. This condition is more aplicable to the spacial plasma problems, for example, in the solar photosphere\'s plasma. It has been calculated, for the first time, the discrete modes of slow waves, proposed theoretically. Its solutions (eigenfunctions and eigenvalues) have also the characteristics of the global modes, called global discrete slow waves. The study of spectral problems for the Reversed Field Pinch configurations was also determined here for both Sturmian eigenmodes for the Alfvén waves and Anti-Sturmian eigenmodes for the slow waves.
105

Coupling Nitrogen Vacancy Centers in Diamond Nanopillars Whispering Gallery Microresonators

Dinyari, Khodadad 11 July 2013 (has links)
For cavity quantum electrodynamics systems (cavity-QED) to play a role in quantum information processing applications and in quantum networks, they must be robust and scalable in addition to having a suitable method for the generation, processing and storage of quantum bits. One solution is to develop a composite system that couples a nitrogen vacancy (NV) center in diamond to a whispering gallery mode supported by a fused silica microsphere. Such a system is motivated by the optical and electron-spin properties of the NV center. The NV center is the leading spin-qubit and exhibits atomic like linewidths at cryogenic temperatures and has spin coherence times greater than milliseconds at room temperature. These long coherence times, coupled with nanosecond scale spin readout and manipulation times, allow for millions of quantum operations to be processed. Silica whispering gallery resonators are the only class of microresonators with quality factor high enough to reach the strong coupling regime, which is necessary for some quantum information processing applications. Integrating these two components into a system that could position a diamond nanopillar near the surface of a deformed-double stemmed microsphere system, with nanometer precision, at 10 K was a major achievement of this research. Cavity resonances in deformed microspheres can be excited with a free-space coupling technique which simplifies their integration into cryogenic environments. In these intentionally deformed resonators, an enhanced evanescent field decay length was observed at specific locations along the ray orbit. The double-stem arrangement enables the cavity resonance to be tuned over 450 GHz, with sub-10 MHz resolution, at 10 K. These two features, the enhanced decay length and broad range tuning with high resolution, are indispensible tools for cavity-QED studies with silica microspheres. Diamond nanopillars were fabricated from single crystal diamond with diameters as small as 140 nm in order to maintain a high quality factor. Studies were conducted on NV centers in nanopillars and bulk diamond to determine their suitability for cavity-QED applications. In an attempt to increase the light-matter interaction between NV centers and whispering gallery modes, diamond substrates were optically characterized that were irradiated with nitrogen ions.
106

Simplifications exactes et structurelles de réseaux de réactions biologiques / Exact and structural simplifications of biological reaction networks

Madelaine, Guillaume 28 February 2017 (has links)
La biologie des systèmes cherche à comprendre et analyser des systèmes biologiques à l'aide de modèles mathématiques et informatiques. L'explosion des données expérimentales entraîne des modèles de plus en plus grands. Afin de pouvoir les analyser facilement ou les simuler rapidement, il est alors nécessaire de pouvoir les simplifier. Dans cette thèse, nous proposons des méthodes de simplifications de réseaux de réactions biochimiques. Ces méthodes sont suffisamment riches pour pouvoir simplifier un grand nombre de réseaux provenant d'applications biologiques. Elles sont contextuelles, permettant de considérer un réseau comme un sous-module d'un modèle plus grand, et de le simplifier sans modifier le comportement du modèle global. Enfin, nos simplifications sont correctes, c'est-à-dire qu'elles préservent la sémantique des réseaux. Dans un premier temps, nous nous intéressons à une sémantique non déterministe, basée sur la possibilité de converger vers les attracteurs du réseau. Nous étudions ensuite des simplifications pour la sémantique déterministe, permettant par exemple de supprimer des espèces intermédiaires à l'équilibre. Enfin, nous nous intéressons à la confluence d'une telle simplification, ainsi qu'au lien entre l'élimination des espèces intermédiaires et le calcul des modes élémentaires d'un réseau. / System biology aims at understanding and analyzing biological systems using mathematical and computational models. The explosion of the number of experimental data leads to larger and larger models. In order to be able to easily analyze them and quickly simulate them, it is necessary to be able to simplify them. In this thesis, we propose simplification methods for biochemical reaction networks. These methods are sufficiently rich to be able to simplify an important number of networks from biological applications. They are contextual, allowing to consider a network as a sub-module of a larger model, and to simplify it without modifying the behavior of the global model. Finally, our simplifications are sound, meaning that they preserve the semantics of the networks. Firstly, we are interested in a non deterministic semantics, based on the capability to converge to some attractors of the network. Then we study some simplifications for the deterministic semantics, allowing for instance to remove intermediate species at steady-state. Finally, we are interested by the confluence of this simplification, as well as the relation between the elimination of intermediate species and the computation of the elementary modes of a network.
107

Entre a qualidade de vida e uma vida com qualidades

Gimenes, Gabriel de Freitas January 2015 (has links)
Esta dissertação se caracteriza como uma problematização da qualidade de vida enquanto uma importante questão que atravessa de diversos modos nossa atualidade. Essa questão é trabalhada no texto em três momentos distintos e complementares, em cada qual se busca compor e decompor uma pergunta que atue como chave de acesso a um nível de complexidade específico e possibilite saltos de compreensão de um momento ao outro. No primeiro momento a qualidade de vida é apresentada como uma expressão de uso comum e generalizado, de modo que o texto se movimenta em um percurso descritivo dos distintos usos e significados dessa expressão. No segundo momento essa falação sobre qualidade de vida é tensionada para que se tornem visíveis alguns enunciados que circulam, se repetem e se transformam num campo aberto de disputas, em função do qual essa qualidade de vida é produzida como uma questão que importa. No terceiro momento essa produção da qualidade de vida como uma questão que importa e que precisa ser gerida é pensada a partir do conceito de dispositivo, e o texto caminha assim como um percurso analítico por entre as distintas linhas que compõem esse dispositivo de qualidade de vida até alcançar as linhas de subjetivação, como limite do dispositivo, como resistência e criação. Após esses três momentos, o texto salta para um interstício poético-filosófico composto por fragmentos de aforismos nietzscheanos que tocam o tema da grande saúde, na busca por uma perspectiva que explore linhas de fuga e de criação pelas quais seja possível pensar e experimentar outros lugares e outros modos para uma vida com qualidades. Ao fim do percurso o texto é apresentado em um pequeno ensaio, que pode ser lido tanto no fim quanto no início da dissertação, no qual é esboçado um contraste entre a qualidade de vida e uma vida com qualidades. / This dissertation is characterized as a problematization of the quality of life as an important issue that permeates in many ways our actuality. This issue is analyzed in the text in three different moments, in each the effort is to build up and down a question that works as an access key to specific complexity levels and that allows jumps in understanding from one moment to another. At the first moment the quality of life is presented as a widely used expression, and the text goes as a description of different uses and meanings of this expression. At the second moment this discourses about quality of life are tensioned to render visible some statements that circulates, are repeated and transformed within an open field of disputes, in relation to which this quality of life is produced as an issue that matters. At the third moment this production of quality of life as an issue that matters and that needs to be managed is thought through the concept of dispositif, and the text goes as an analytical route through the distinct lines that composes this dispositif until it reaches the lines of subjectification, as the limit of the dispositif, as resistance and creation. After this discussion in three moments, the text jumps to a poetic-philosophic interstice made of fragments of some nietzschean aphorisms that touches the theme of great health, in a search for some perspective that explores some possible lines of escape and creation by which it is possible to experiment another places and modes for a life with qualities. At the end of this track the text is presented through a little essay, that can be read both at the end or at the beginning of the text, in which it is sketched a contrast between the quality of life and a life with qualities.
108

Etude de la propagation des ondes élastiques de Lamb dans les matériaux composites micro/nano structurés : Application pour l’ingénierie des propriétés physiques des résonateurs électromécaniques / Lamb wave propagation in composite membranes based on micro/nano structured materials : application to resonators physical properties engineering

Moutaouekkil, Mohammed 15 December 2018 (has links)
Le contrôle de la propagation des ondes élastiques repose principalement sur la conception de milieu artificiel à base de matériaux structurés pour obtenir une ingénierie avancée de la dispersion de la propagation. Au cours de la thèse, la dispersion du mode (S0) dans des membranes micro-structurées à base d’AlN a été numériquement investiguée et les applications qui en découlent explorées. Il est mis en évidence le lien fort entre la dispersion du mode et la sensibilité aux perturbations externes en combinant la membrane d’AlN avec une couche de SiO2 structurée en rubans. En particulier, il est montré qu’il est possible d’obtenir un TCF=0 pour les résonateurs sans presque aucune dégradation du coefficient K2. Il est montré qu’il est possible d’ouvrir des bandes interdites avec une largeur de l’ordre de 50% en structurant l’AlN sous forme de rubans ou en utilisant des piliers pour former un PhnC. Sur cette base, des designs de cavités et de guides d’ondes sont proposés et leurs performances sont étudiées en fonction des paramètres géométriques. Il est également proposé un nouveau design de cavité basé sur l’introduction d’un défaut résonant dans le PhnC sous forme de disque de dimension très petite par-rapport à la taille de la cellule élémentaire. Le défaut permet d’introduire des modes quasi-plats dans le diagramme de bande et permet en conséquence la conception d’une nouvelle génération de dispositifs phononiques robustes pour des applications en traitement du signal et capteurs. Les structures optimales sont utilisées pour la conception de capteur de champs magnétiques, une sensibilité de 5% est obtenue pour le mode localisé dans le cas d’un disque magnéto-élastique / The control of elastic wave propagation relies mainly on the design of artificial media based on structured materials to achieve advanced propagation dispersion engineering. During the thesis, the dispersion of the mode (S0) in micro-structured membranes based on AlN was numerically investigated and the resulting applications explored. The strong link between mode dispersion and sensitivity to external disturbances is highlighted by combining the AlN membrane with a layer of SiO2 structured into strips. In particular, it is shown that it is possible to obtain a TCF = 0 for the resonators without any degradation of the K2 coefficient. It is shown that it is possible to open wide band-gaps of 50% by structuring the AlN in the shape of strips or using pillars to form a PhnC. On this basis, designs of cavities and waveguides are proposed and their performances are studied according to the geometrical parameters. It is also proposed a new cavity design based on the introduction of a resonant defect with a disc shape in the PhnC and presenting very small size in comparison to the unit cell. The defect makes it possible to introduce quasi-flat modes in the band diagram and consequently allows the design of a new generation of phononic devices for signal processing and sensor applications. The optimal structures are used to design a magnetic field sensor design, a sensitivity of 5% is obtained for the localized mode in the case of defect based on magneto-elastic thin film.
109

The impact of embedding multiple modes of representation on student construction of chemistry knowledge

McDermott, Mark Andrew 01 May 2009 (has links)
This study was designed to examine the impact of embedding multiple modes of representing science information on student conceptual understanding in science. Multiple representations refer to utilizing charts, graphs, diagrams, and other types of representations to communicate scientific information. This study investigated the impact of encouraging students to embed or integrate the multiple modes with text in end of unit writing-to-learn activities. A quasi-experimental design in which four separate sites consisting of intact chemistry classes taught by a separate teacher at each site was utilized. At each site, approximately half of the classes were designated treatment classes and students in these classes participated in activities designed to encourage strategies to embed multiple modes with text in student writing. The control classes did not participate in these activities. All classes participated in identical end of unit writing tasks in which they were required to use at least one mode other than text, followed by identical end of unit assessments. This progression was then repeated for a second consecutive unit of study. Analysis of quantitative data indicated that in several cases, treatment classes significantly outperformed control classes both on measures of embeddedness in writing and on end of unit assessment measures. In addition, analysis at the level of individual students indicated significant positive correlations in many cases between measures of student embeddedness in writing and student performance on end of unit assessments. Three factors emerged as critical in increasing the chances for benefit for students from these types of activities. First, teacher the level of implementation and emphasis on the embeddedness lessons was linked to the possibility of conceptual benefit. Secondly, students participating in two consecutive lessons appeared to receive greater benefit, inferring a cumulative benefit. Finally, differential impact of the degree of embeddedness on student performance was noted based on student's level of science ability prior to the initiation of study procedures.
110

Acquisition and Generalization of Tacts across Stimulus Modes in Children Diagnosed with Autism Spectrum Disorder

Correa Gómez, Luz Elena 24 March 2015 (has links)
This study evaluated the speed of acquisition and level of generalization of tacts across three different stimulus modes: picture-flashcard, video clip, and 3D object. Three young children diagnosed with autism participated in this study. The acquisition of tacts was evaluated during Discrete Trial Training sessions (DTT). Two of the three participants learned the tacts more rapidly in the video clip condition in contrast with the picture condition. All three participants generalized the three tacts learned through a specific stimulus mode to the remaining stimulus modes. One week after the generalization test, all participants generalized to all novel 3D objects.

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