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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.
141

Laudato Si' in the United States: Constructing a Public Theology

DiLeo, Daniel Robert January 2017 (has links)
Thesis advisor: Kenneth R. Himes / This project constructs a public theology of Laudato Si' with which Catholics in the United States might shape climate change discourse, policy, and action. Chapter 1 outlines anthropogenic climate change and reviews magisterial Catholic teaching about this issue. Chapter 2 argues that the Christian church should engage with the world through both secular and faith-based language in the forms of public philosophy and public theology. Chapter 3 considers Catholic public theology in the contemporary U.S. Chapter 4 considers LS as a document of public theology and demonstrates how this document both develops Catholic public theology in the social encyclical tradition and is organized according to a modified Pastoral Circle. Chapter 5 analyzes a nationally representative public opinion survey of American adults to discern the likelihood that messages based on LS might move Americans’ climate change opinions more in line with Pope Francis’s ecological vision. Chapter 6 combines these insights with the reflections in Chapter 3 to construct an American Catholic public theology of LS that might help accordingly shape American climate change discourse, policy and action. The project thus combines theological ethics and social science to engage in applied ecological theological ethics and constructively suggest the contents of an evidence-based American Catholic public theology of LS with which the church might advance Pope Francis’s ecological vision. / Thesis (PhD) — Boston College, 2017. / Submitted to: Boston College. Graduate School of Arts and Sciences. / Discipline: Theology.
142

Efeitos da adição de carbonetos na resistência ao desgaste e à corrosão de uma liga auto-fluxante depositada por aspersão térmica / Effect of carbides addition in the wear and corrosion resistance of a sell-fluxing coating deposited by thermal spraying

Alencar, Gladston Torres de Mesquita 14 May 2009 (has links)
Neste trabalho, visando-se melhorar o desempenho ao desgaste e/ou à corrosão de revestimentos de ligas auto-fluxantes, amostras de aço SAE 1020 foram revestidas pelo processo de aspersão térmica, sendo que uma delas foi revestida apenas com uma liga auto-fluxante a base de níquel (\'NI\"CR\"B\"SI\"C\') e outras duas, às quais aplicou-se essa liga com adições de carboneto de boro ou carboneto de silício. As camadas foram caracterizadas por meio de ensaios micrográficos ópticos e eletrônicos, microdurezas, corrosão e de microdesgaste. A camada adicionada com carboneto de boro apresentou o maior nível de dureza e melhor desempenho ao desgaste, seguida pela camada com carboneto de silício e a liga auto-fluxante pura. As amostras adicionadas de carboneto de boro e silício apresentaram comportamentos similares à corrosão, com potenciais de corrosão superiores ao da amostra sem adição. / In this work, aiming to improve the wear and/or corrosion performance of self-fluxing alloys coatings, samples SAE 1020 steel were coated by thermal spray process, one of then was coated only with a self-fluxing nickel-based (\'NI\"CR\"B\"SI\"C\') alloy and two others, in which was applied this alloy with additions of boron carbide or silicon carbide. The coatings were characterized by means of optical and electronic micrography, microhardness, corrosion and microwear tests. The coating added with boron carbide showed the highest level of hardness and the better wear performance, followed by the coating with silicon carbide and the pure self-fluxing alloy. The samples added with boron or silicon carbide showed similar corrosion performance, with higher corrosion potential in comparison to that presented by the sample without addition.
143

Ab soliloquiorvm ad hermenevma seipso ex Avrelii Avgvstini vsqve Paul Ricoeur alteritas / ipsetates / De solil?quios ? hermen?utica de si-mesmo : via Aur?lio Agostinho ? alteridade / ipseidade de Paul Ricouer

Minghetti, Antonio Auresnedi 19 December 2016 (has links)
Submitted by Caroline Xavier (caroline.xavier@pucrs.br) on 2017-05-30T17:08:43Z No. of bitstreams: 1 TES_ANTONIO_AURESNEDI_MINGHETTI_COMPLETO.pdf: 3211068 bytes, checksum: f5eb0b7034faa02043b7c1f7d60bb94c (MD5) / Made available in DSpace on 2017-05-30T17:08:43Z (GMT). No. of bitstreams: 1 TES_ANTONIO_AURESNEDI_MINGHETTI_COMPLETO.pdf: 3211068 bytes, checksum: f5eb0b7034faa02043b7c1f7d60bb94c (MD5) Previous issue date: 2016-12-19 / Le Delphic NOSCE TE IPSVM, en le oeuvre Soliloquiorum d`Aurelii Augustini (345-430 d.C.), ?merge dans la nouvelle configuration si analys?e dans la perspective d'apporter des r?ponses aux exigences fondamentales de la condition humaine, lorsque le rh?teur du primat l'existence transcendantale apr?s ? la r?flexion sp?culative, d?riv? du cogito cart?sienne, ?tendu plus tard par Kant et les successeurs de philosophie Fran?aise dans ce moule jusqu'? l'arc de compr?hension herm?neutique du vous et d?mant?le l'ego cogito cogitatum, pour acc?der ? la dimension ontologique de vous-m?me sur un cogito incarn?. Le point focal de cette th?se est de d?montrer que l`interpr?tation de la l'intentionnalit? de la conscience en Soliloquiorum, expose la fa?on "Je pense augustinienne" pr?cise que dans l'homme int?rieur serait habitent la V?rit? lorsque vous ajoutez en reconnaissant que, dans l'homme int?rieur habite la V?rit? et, s'?claire en ajoutant l'ips?it? sur l`dimension assise pr?-predicat d'identit? (soi-m?me) ?tablie dans la vie v?cue ? l'identit? d?Augustin, ce qui lui a donn? une teo-philosophie r?fl?chissante pour indiquer le sens de votre existence comme singularit? concr?te, irrempla?able, impermutable qui seulement c'est laiss? appr?hender dans la rencontre du m?me avec l'autre soi dans une relation dialectique, construit entre votre m?met? et vos et Ips?it?, caract?ris? dans lez sur ?tudes Ricoeuriennes, dans le oeuvre Soi-m?me comme un Autre sur comme l'alt?rit?. / O d?lfico NOSCE TE IPSVM, a partir da obra Soliloquiorum de Aurelio Agostinho (345-430 d.C.), emerge em nova conforma??o se analizado sob a perspectiva de provimento de respostas ?s demandas fundamentais da condi??o humana, quando o retor d? primazia a exist?ncia transcendental sobre a reflex?o especulativa derivada do cogito cartesiano, alargada posteriormente por Kant e os sucessores da filosofia francesa, no que ent?o se amolda ao arco hermen?utico da compreens?o de si e, desmantela o ego cogito cogitatum, para aceder ? dimens?o ontol?gica desse si em um cogito encarnado. O ponto fulcral desta tese ? demonstrar que, a interpreta??o da intencionalidade da consci?ncia em Soliloquiorum, exp?e o modo como o ?eu penso augustiniano? aclara que no homem interior habitaria a Verdade, ao se acrescer a ipseidade assentada nas dimens?es pr?-predicativas da vida vivida ? identidade (soi-m?me) de Agostinho, o que proporcionou uma t?o-filosofia reflexiva a lhe indicar o sentido de sua exist?ncia como singularidade concreta, irrepet?vel e impermut?vel, que s? se deixa apreender neste encontro do mesmo com o outro de si, em uma rela??o dialectica interna entre sua mesmidade e sua ipseidade, constitu?das como a Alteridade (comme un autre) dos ?tudes Ricoeuriennes, em sua obra Soi-m?me comme un Autre.
144

O diagnóstico das relações interfuncionais de SI/TI de uma organização em um modelo de governança

CAMPOS, Bruna Maciel January 2007 (has links)
Made available in DSpace on 2014-06-12T17:40:52Z (GMT). No. of bitstreams: 2 arquivo7265_1.pdf: 1050679 bytes, checksum: ac60254499322084c75b7a14baa27f27 (MD5) license.txt: 1748 bytes, checksum: 8a4605be74aa9ea9d79846c1fba20a33 (MD5) Previous issue date: 2007 / É consenso na literatura os benefícios que as organizações podem obter para o seu negócio com a utilização de sistemas de informação (SI) e tecnologia da informação (TI), tais como: melhores produtos e serviços, maior satisfação do cliente e vantagens competitivas. No sentido de utilizar todo o potencial dos sistemas de informação, muitas metodologias de planejamento de SI/TI foram desenvolvidas nas últimas décadas buscando alinhar a estratégia de utilização de SI/TI à estratégia do negócio. Recentemente, pelo fato do fornecimento de soluções por parte da área de SI/TI exigir patrocínio e comprometimento de toda a organização, foi identificado na literatura que apenas um processo formal de planejamento e sua maturidade não são suficientes para que a área de SI/TI de uma organização desempenhe de forma eficaz seu papel, ou seja, contribua para que a organização alcance seus objetivos empresariais. Assim as atenções se voltam para as relações da função SI/TI com as demais funções do negócio. Neste contexto, este trabalho propõe um modelo que represente os possíveis cenários em que se encontram as relações da função SI/TI com as demais funções do negócio e também sugere um procedimento baseado em informações, as quais falam da visão e interação da função SI/TI pela gestão da organização e seus usuários, obtidas mediante aplicação de um questionário. Este procedimento é utilizado para identificar em que estágio as relações da função SI/TI com o negócio se encontram, conforme o modelo proposto. No trabalho também são sugeridas recomendações de melhoria para os aspectos das relações que foram diagnosticadas insatisfatórias. Para ilustrar a aplicação do procedimento sugerido e a classificação das relações, segundo o modelo proposto, foram feitos estudos de caso em 4 (quatro) empresas da Região Metropolitana do Recife escolhidas por conveniência do pesquisador
145

Studium mobility atomů kovů na povrchu Si(100) pomocí STM / STM study of metal adatom mobility on Si(100) surface

Rozbořil, Filip January 2012 (has links)
Surface diffusion of group III and IV metals on Si(100) is studied. Three methods for obtaining diffusion barriers are presented and discrepancies in published results are discussed. Room temperature growth of Al on Si(100) is studied using STM, observing a monomodal scaled island size distribution function. A Kinetic Monte Carlo simulation model is employed to obtain bonding energies and diffusion barriers for Al/Si(100). The best agreement between the measured and simulated characteristics is found for strongly anisotropic diffusion with barriers 0.60 eV in the direction orthogonal to the Si dimer rows and 0.80 eV in the parallel direction. Modifications of the cooling system required for observing metal adatom diffusion on Si(100) using STM are described and the first low-temperature experiment is carried out.
146

Characterization of Electrically Active Defects at Nb/Si Interface Using Current Transport and Transient Capacitance Measurements

January 2018 (has links)
abstract: In this project, current-voltage (I-V) and Deep Level Transient Spectroscopy (DLTS) measurements are used to (a) characterize the electrical properties of Nb/p-type Si Schottky barriers, (b) identify the concentration and physical character of the electrically active defects present in the depletion region, and (c) use thermal processing to reduce the concentration or eliminate the defects. Barrier height determinations using temperature-dependent I-V measurements indicate that the barrier height decreases from 0.50 eV to 0.48 eV for anneals above 200 C. The electrically-active defect concentration measured using DLTS (deep level transient spectroscopy) drops markedly after anneals at 250 C. A significant increase in leakage currents is almost always observed in near-ideal devices upon annealing. In contrast, non-ideal devices dominated by leakage currents annealed at 150 C to 250 C exhibit a significant decrease in such currents. / Dissertation/Thesis / Masters Thesis Materials Science and Engineering 2018
147

Hermêutica e subjetividade, de Agostinho e Hipona a Paul Ricoeur - Três estudos sobre o si, a memória e a identidade / Hermeneutics and subjectivity, from Agostinho de Hipona to Paul Ricoeur. Three studies on the Self, Memory and Identity

Bruzzone, Andres 19 April 2012 (has links)
Nosso texto propõe uma leitura da Confissões de Agostinho de Hipona com elementos da hermenêutica filosofia de Paul Ricoeur, especialmente a noção da identidade narrativa. O si, a memória e a identidade são pontos de encontro onde as filosofias de ambos os autores dialogam e se iluminam reciprocamente. / Our text examines Augustines Confessions with the help of Paul Ricoeur philosophical hermeneutics, specially the notion of narrative identity. The self, memory and identity are the areas where authors meet to a mutual dialogue that enlightens both philosophies.
148

Intégration et fiabilité d'un disjoncteur statique silicium intelligent haute température pour application DC basse et moyenne tensions / Integration and reliability of a smart solid state circuit breaker for high temperature designed for low and medium DC voltage.

Roder, Raphaël 04 December 2015 (has links)
Cette thèse présente l'étude et la réalisation d'un disjoncteur statique tout silicium et intelligent pouvant fonctionner à haute température (200°C) pour des applications de type DC basse et moyenne tensions. Plusieurs applications dans l’aéronautique, l’automobile et les transports ferroviaires poussent les composants à semi-conducteur de puissance à être utilisés à haute température. Cependant, les Si-IGBT et Si-CoolMOSTM actuellement commercialisés ont une température de jonction spécifiée et estimée à 150°C et quelque fois à 175°C. L’une des faiblesses des convertisseurs provient de la réduction du rendement avec l’augmentation de la température de jonction des composants à semiconducteur de puissance qui peut amener à leur destruction. La solution serait d’utiliser des composants grand-gap (SiC, GaN), qui autorisent un fonctionnement à une température de jonction plus élevée ;mais ces technologies en plein essor ont un coût relativement élevé. Une solution alternative serait de faire fonctionner des composants en silicium à une température de jonction voisine de 200°C afin de conserver l’un des principaux intérêts du silicium en termes de coût. Avant de commencer, le premier chapitre portera sur un état de l’art des différentes techniques de protection aussi bien mécanique que statique afin d’identifier les éléments essentiels pour la réalisation du circuit de protection. Les disjoncteurs hybrides seront aussi abordés afin de voir comment ceux-ci arrivent à combler les lacunes des disjoncteurs mécaniques et purement électroniques (statiques). A partir du chapitre précédent, un disjoncteur statique intelligent de faible puissance sera réalisé afin de mieux cerner les différentes difficultés qui sont liées à ce type de disjoncteur. Le disjoncteur statique sera réalisé à partir de fonction analogique de telle façon à ce qui soit autonome et bas cout. Il en ressort que les inductances parasites ainsi que la température des composants à base de semi-conducteurs ont un impact significatif lors de la coupure.Le chapitre III portera sur une analyse non exhaustive, vis-à-vis de la température, de différents types d’interrupteurs contrôlés à base de semi-conducteur de puissance en s’appuyant sur plusieurs caractérisations électriques (test de conduction, tension de seuil, etc) afin de sélectionner le type d’interrupteur de puissance qui sera utilisé pour le chapitre IV. Comme il sera démontré, les composants silicium à super jonction peuvent se rapprocher du comportement des composants à base de carbure de silicium pour les basses puissances. Un disjoncteur statique 400V/63A (courant de court-circuit prédictible de 5kA) sera étudié et 4développé afin de mettre en pratique ce qui a été précédemment acquis et pour montrer la compétitivité du silicium pour cette gamme de puissance. / This thesis presents a study about a smart solid state circuit breaker which can work at 200°C forlow and medium voltage continuous applications. Some applications in aeronautics, automotive,railways, petroleum extraction push power semiconductor devices to operate at high junctiontemperature. However, current commercially available Si-IGBT and Si-CoolMOS have basically amaximum junction temperature specified and rated at 150°C and even 175°C. Indeed, the main problemin conventional DC-DC converters is the switching losses of power semiconductor devices (linked to thetemperature influence on carrier lifetime, on-state voltage, on-resistance and leakage current) whichdrastically increase with the temperature rise and may drive to the device failure. Then, the use of wideband gap semiconductor like SiC or GaN devices allows higher junction temperature operation (intheory about 500°C) and higher integration (smaller heatsink, higher switching frequency, smallconverter), but are still under development and are expensive technologies. In order to keep theadvantage of low cost silicon devices, a solution is to investigate the feasibility to operate such devicesat junction temperature up to 200°C.Before starting the first starting chapter is a stat of the art of protectives circuit technics as well asmechanics as statics in order to identify essentials elements to develop the protective circuit. Hybridprotective circuits are approached too.From the precedent chapter, a smart and low power solid state circuit breaker is realized to identifyproblems which are linked with this type of circuit breaker. Solid state circuit breaker is developed withanalog components in a way that is autonomous and low cost. It’s follow that stray inductance andtemperature have an important impact when a default occurs.Chapter III give an analyze on different silicon power semiconductor dice towards temperature5relying on statics and dynamics characteristics in order to find the best silicon power switch which beused in the chapter IV. It has been shown that super junction MOSFET has the same behavior at lowpower than silicon carbide MOSFET.Solid state circuit breaker (400V/63A) has been studied and developed, in order to use all theknowledge previously acquired and to show the competitively of the silicon for this power range.
149

Diseño experimental para el estudio de la posible función de la citrato sintasa mitocondrial de Annona cherimola (Ac-mCS) en la maduración de frutos

Lagreze Pérez, Jorge Javier. 06 1900 (has links)
Título de Ingeniero en Biotecnología Molecular. / Durante la maduración de los frutos, existen cambios a nivel fisiológico y bioquímico, como son: variaciones en la respiración, textura, color y acidez; como consecuencia de la remodelación de la pared celular, síntesis y degradación de pigmentos y variaciones en la acumulación de azúcares y ácidos orgánicos. Los dos últimos, son utilizados por las células vegetales como sustratos respiratorios, y particularmente los ácidos orgánicos como el ácido cítrico y málico tienden a ser degradados a lo largo de la maduración. En contraposición a lo anterior, estudios previos realizados en nuestro laboratorio en frutos de Annona cherimola var. Concha Lisa, se encontró mayores niveles de ácido cítrico, mayor actividad citrato sintasa y una mayor acumulación de transcrito codificante para la enzima citrato sintasa (CS) en el estado de madurez de consumo en comparación con el estado analizado en cosecha. Considerando lo anterior, la enzima CS parece tener un rol importante en la acumulación de citrato en frutos de chirimoya. Como una primera aproximación al estudio de su posible función, este seminario de título tiene por objetivo general caracterizar Ac-mCS mediante su localización subcelular en N. tabacum y la transformación estable de S. lycopersicum, a través de dos estrategias enfocadas en la expresión heteróloga de la enzima mCS de A. cherimola var. Concha lisa. Se observó mediante microscopía confocal, que la enzima Ac-mCS posee localización mitocrondial en hojas de Nicotiana tabacum. Por otro lado, para la transformación de tomate se construyeron y utilizaron dos vectores para la expresión heterologa de Ac-mCS bajo el control del promotor CaMV 35S y de un fragmento del promotor de poligalacturonasa de tomate (PG), sometiéndose los explantes de tomate a la transformación y organogénesis somática, pero sin lograr obtener plantas transgénicas adultas. / During fruit ripening, biochemichal and phisiological changes occur, such as variations in respitarory rate, texture, colour, and acidity; as a consequence of the cell wall remodelation, pigments synthesis and degradation, and variations in the accumulation of sugar and organic acids. The latter ones, are vegetable cell metabolic substrates, and particularly organic acids such as citric and malic acid, tend to be degraded during ripening. However, previous studies held in our laboratory in Annona cheriloma cv Concha Lisa fruits, showed increased levels in citric acid, increased citrate synthase activity and large mitochondrial citrate synthase (Ac-mCS) transcript accumulation at consumption maturity compared to the analyses performed at harverst. Considering all these points, citrate synthase seems to account for an important role in the citrate accumulation in cherimola fruit. As a first approach to the potential function of this enzyme, the main objective of this work was to characterize Ac-mCS by subcellular localization in N. tabacum, and stable transformation of S. lycopersicum, using two strategies, both of them focused in the mCS enzyme heterologue expression from A. cherimola cv. Concha lisa. Confocal microscopy in Nicotiana tabacum leaves revealed that the Ac-mCS enzyme has a mitochondrial localization. On the other hand, two expression vectors were built and used to express Ac-mCS under the transcriptional control of the CaMV 35S promoter or the tomato polygalacturonase promoter fragment (PG).Tomato explants were, subjected to the transformation process, and somatic organogenesys, but no adult transgenic plants were obtained.
150

New quaternary amorphous materials Si-B-C-N: reactive magnetron sputtering and an ab-initio study

Houska, Jiri January 2007 (has links)
Doctor of Philosophy / First part of the thesis is focused on experimental preparation of new hard quaternary amorphous materials Si-B-C-N with high thermal stability. Materials were prepared in the form of thin films using reactive magnetron sputtering. The technique used proved to be suitable for reproducible synthesis of these materials. The Si-B-C-N films were generally found to be amorphous with low compressive stress and good adhesion to silicon or glass substrates. The process and film characteristics were controlled by varying the sputter target composition, the Ar fraction in the N2–Ar gas mixture, the negative rf-induced substrate bias, and the substrate temperature. Main conclusions describe the relationships between process parameters, discharge and deposition characteristics and film properties (elemental composition, chemical bonding structure, material hardness, compressive stress or electrical conductivity of materials prepared). Second part of the thesis is focused on ab-initio simulations of structures of experimentally prepared Si-B-C-N materials. In the performed liquid-quench simulations, the Kohn-Sham equations for the valence electrons are expanded in a basis of plane wave functions, while core electrons were represented using Goedecker-type pseudopotentials. We simplified the ion bombardment process by assuming that the primary impact creates a localized molten region of high temperature and sufficiently short cooling time, commonly referred to as a thermal spike. Main conclusions deal with N2 formation in studied materials, effect of implanted Ar on structure and properties of prepared materials, ability of Si to relieve that part of compressive stress which is caused by implanted Ar, and ability of B to improve thermal stability of Si-B-C-N materials. The calculated results are compared with experiment.

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