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Puzenat, Amélie. "Conversions à l'islam et islams de conversion : dynamiques identitaires et familiales". Paris 7, 2010. http://www.theses.fr/2010PA070041.
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Au regard de trajectoires de français et de françaises convertis à l'islam, cette thèse porte sur les redéfinitions identitaires personnelles et familiales engendrées par la conversion. Des parcours de croyants non-pratiquants à ceux de pratiquants orthodoxes, la conversion est appréhendée au croisement des itinéraires individuels et des évolutions religieuses contemporaines. A l'ère de la sécularisation, la conversion à l'islam, emblématique d'une autonomisation mais aussi d'une transgression certaine, demeure fréquemment prise aux mailles du processus de réislamisation. Elle symbolise le passage de la frontière entre des groupes ethniques constitués comme tels et suscite de vives réactions au sein de l'entourage. Plus précisément, cette recherche interroge la réorganisation des liens familiaux en situation de « mixité » conjugale. Elle s'intéresse également à la reconfiguration des relations de genre et à la mise en place de nouveaux modèles éducatifs. La parentalité qui se profile au sein des familles révèle un fort investissement maternel et rend plus largement compte de la production de nouvelles normes conjugales et éducatives s'apparentant à un islam dit « néo-communautaire »Observing the journey of French men and women who converted to Islam, this thesis delves into identity redefinitions on personal and family levels, resulting from the conversion. From experiences of non-practising believers to those of orthodox believers, the conversion is grasped at the intersection of individual itineraries and contemporary religious evolutions. In an era of secularisation, the conversion to Islam, symptomatic of individualisation but also of transgression, remains frequently embedded in an Islamic transnational revival. The conversion symbolizes the crossing of a border between ethnic groups constituted as such and arouses strong reactions within the converter's close circle. More precisely, this research questions the re-organization of family relationships in a situation of mixed marriage. It also looks into the re-configuration of gender relationships and the constitution of new educational models. The parenthood one can observe in these families reveals a strong maternal investment and, more generally, accounts for the creation of new marital and educational norms related to a "neo-communitarian" Islam
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Machado, Anderson Fraiha. "Conversão de voz inter-linguística". Universidade de São Paulo, 2013. http://www.teses.usp.br/teses/disponiveis/45/45134/tde-04062013-130812/.
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A conversão de voz é um problema emergente em processamento de fala e voz com um crescente interesse comercial, tanto em aplicações como Tradução Fala para Fala (Speech-to-Speech Translation - SST) e em sistemas Text-To-Speech (TTS) personalizados. Um sistema de Conversão de Voz deve permitir o mapeamento de características acústicas de sentenças pronunciadas por um falante origem para valores correspondentes da voz do falante destino, de modo que a saída processada é percebida como uma sentença pronunciada pelo falante destino. Nas últimas duas décadas, o número de contribuições cientícas relacionadas ao problema de conversão de voz tem crescido consideravelmente, e um panorama sólido do processo histórico, assim como de técnicas propostas são indispensáveis para contribuição neste campo. O objetivo deste trabalho é realizar um levantamento geral das técnicas utilizadas para resolver o problema, apontando vantagens e desvantagens de cada método, e a partir deste estudo, desenvolver novas ferramentas. Dentre as contribuições do trabalho, foram desenvolvidos um método para decomposição espectral em termos de bases radiais, mapas fonéticos articiais, agrupamentos k-verossímeis, funções de empenamento em frequência entre outras, com o intuito de implementar um sistema de conversão de voz inter-linguístico independente de texto de alta qualidade.Voice conversion is an emergent problem in voice and speech processing with increasing commercial interest, due to applications such as Speech-to-Speech Translation (SST) and personalized Text-To-Speech (TTS) systems. A Voice Conversion system should allow the mapping of acoustical features of sentences pronounced by a source speaker to values corresponding to the voice of a target speaker, in such a way that the processed output is perceived as a sentence uttered by the target speaker. In the last two decades the number of scientic contributions to the voice conversion problem has grown considerably, and a solid overview of the historical process as well as of the proposed techniques is indispensable for those willing to contribute to the eld. The goal of this work is to provide a critical survey that combines historical presentation to technical discussion while pointing out advantages and drawbacks of each technique, and from this study, to develop new tools. Some contributions proposed in this work include a method for spectral decomposition in terms of radial basis functions, articial phonetic map, warping functions among others, in order to implement a text-independent crosslingual voice conversion system of high quality.
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Damas, Juan Roberto. "On Conversion". Thesis, Virginia Tech, 2002. http://hdl.handle.net/10919/35812.
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The conversion of the convent of San Francisco into a school of architecture in Havana, comes out of my omnipresent desire to work with old structures, my faith in architectural education, and my love for he city in which I was born. My intention was to propose an alternative to conventional restoration and preservation. From the mutilated body of the convent, and the seed of education planted by the monks the new school sprung. The memory of the lost limbs, still present in the city, began to materialize slowly, letting the old structure breathe again.Master of Architecture
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York, Andrew P. E. "Methane conversion chemistry". Thesis, University of Oxford, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.334954.
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Brown, S. S. "Conversion of notations". Thesis, University of Cambridge, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.596970.
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Music, engineering, mathematics, and many other disciplines have established notations for writing their documents. The effectiveness of each of these notations can be hampered by the circumstances in which it is being used, or by a user's disability or cultural background. Adjusting the notation can help, but the requirements of different cases often conflict, meaning that each new document will have to be transformed between many versions. Tools that support the programming of such transformations can also assist by allowing the creation of new notations on demand, which is an under-explored option in the relief of educational difficulties. This thesis reviews some programming tools that can be used to manipulate the tree-like structure of a notation in order to transform it into another. It then describes a system "4DML" that allows the programmer to create a "model" of the desired result, from which the transformation is derived. This is achieved by representing the structure in a geometric space with many dimensions, where the model acts as an alternative frame of reference. Example applications of 4DML include the transcription of songs and musical scores into various notations, the production of specially-customised notations to assist a sight-impaired person in learning Chinese, an unusual way of re-organising personal notes, a "website scraping" system for extracting data from on-line services that- provide only one presentation, and an aid to making mathematics and diagrams accessible to people with severe print disabilities. The benefits and drawbacks of the 4DML approach are evaluated, and possible directions for future work are explored.
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Borer, Tim. "Television standards conversion". Thesis, University of Surrey, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.317305.
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Condoluci, Andrea <1990>. "Beta-Conversion, Efficiently". Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2020. http://amsdottorato.unibo.it/9444/1/main-9.pdf.
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Type-checking in dependent type theories relies on conversion, i.e. testing given lambda-terms for equality up to beta-evaluation and alpha-renaming.
Computer tools based on the lambda-calculus currently implement conversion by means of algorithms whose complexity has not been identified, and in some cases even subject to an exponential time overhead with respect to the natural cost models (number of evaluation steps and size of input lambda-terms).
This dissertation shows that in the pure lambda-calculus it is possible to obtain conversion algorithms with bilinear time complexity when evaluation is carried following evaluation strategies that generalize Call-by-Value to the stronger case required by conversion.
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Santos, João Pedro Pires dos. "Comportamento online dos portugueses e identificação dos factores de conversão". Master's thesis, Instituto Superior de Economia e Gestão, 2018. http://hdl.handle.net/10400.5/17287.
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Mestrado em Econometria Aplicada e PrevisãoO presente estudo tem como objectivo a determinação de indicadores avançados que permitam identificar indivíduos susceptíveis de se converterem a um sítio online relativo aos sectores da banca e seguros. Para tal, a partir de uma amostra que contém informação comportamental online de um painel de utilizadores portugueses, foi feita uma análise descritiva aos dados, seguida da estimação de dois modelos de regressão logística respeitante a cada sector alvo de análise. A análise descritiva aos dados demonstra que variáveis demográficas, tais como idade, região, sexo e situação laboral do indivíduo, foram relevantes na distinção dos indivíduos convertidos e não convertidos. Do primeiro modelo logit estimado, relativo à banca, retiramos o motor de busca e a combinação de indicadores comportamentais com características demográficas, como as variáveis que melhor prevêem a conversão de um indivíduo no sector. Jovens com idades entre os 18 e 30 anos, recentemente pais, que passam muito tempo em casa e não estão habituados à internet, constituem um dos perfis mais destacados na probabilidade de ocorrência do evento conversão em banca. Relativamente à segunda regressão estimada, para os seguros, conclui-se que o último clique antes da conversão é o mais relevante. Um indivíduo é mais passível de se converter ao sector de seguros, partindo directamente da página de uma grande empresa. Este fenómeno está implicitamente relacionado com os funcionários que beneficiam de seguro de saúde de uma dada empresa.
The present study's goal is identifying the factors that most explain the conversion of internet users in a website related to the banking and insurance sectors. From a sample containing online behaviour data about a panel of portuguese users, a descriptive analysis was done, followed by the estimation of two logistic regression models for each sector of analysis. The descriptive analysis of data showed that demographic variables such as age, sex, and the individual's work situation, were relevant to distinguish between converted and unconverted individuals. The first estimated logit model, relative to banking, points the use of search engine and a combination of behavioral indicators with demographic characteristics, as the variables that best explains the conversion in the sector. For the second logistic regression, about the insurance sector, we conclude the last click immediately before the conversion, is the most relevant to the event. There are bigger odds an internet user gets converted in the insurance sector, by jumping directly from a website regarded to a big corporation. This phenomenon is linked to employees that benefits from a health insurance service, provided by the corporation.
info:eu-repo/semantics/publishedVersion
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Koros, Georgios. "Reducing the cost of conversion projects through design for ship conversion". Thesis, University of Newcastle upon Tyne, 2017. http://hdl.handle.net/10443/3667.
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The Thesis develops design and production methods to reduce cost, duration and risks of conversions. It reviews the literature on the nature of conversion and its correlation to ship-repair and shipbuilding. It examines the market, in particular for tanker to bulk carrier conversions. Literature on ship design for production, project management and risk is reviewed to identify potentially valuable ideas to improve the conversion process. The case study conversion was completed in a conversion yard, using conventional techniques and planning. The design of the final bulk carrier was also conventional. The work was completed afloat, creating potential risk of structural damage which required carefully managed actions, e.g. work inside cargo holds to be carried out sequentially. A project completion review identified this and access difficulties as slowing the work. A number of cost inducing conversion bottlenecks had not been obvious at the start. An alternative design is proposed for subsequent projects, moving strength members above deck, minimizing bottlenecks present with the initial design. Indicatively, by providing adequate deck strength early in the conversion, work in the cargo holds could proceed more quickly. A plan for conversion is developed alongside the design. The alternative design shows a significant cost and time saving. The results are developed to offer a general basis for design for conversion, adapting shiprepair and design for production principles and proposes the following: - The need to understand conversions in depth and improve planning. - The need to engage all parties (design and production) in a collaborative project. - Mitigation of risks focusing on production methods. - A dedicated Goal-Based Design for Conversion approach that avoids, where possible, difficult internal structural work. - Evaluating the need for Dry Dock in major conversions; it may not always be necessary or beneficial, contrary to popular belief and current Bibliography.
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Chase, Zachary J. "Pacha and performativity: the colonial conversion of prehistoric Huarochirí". Pontificia Universidad Católica del Perú, 2017. http://repositorio.pucp.edu.pe/index/handle/123456789/113297.
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In this chapter I consider the religious conversion of Indian populations as the primary objective of Catholic evangelization during the first two centuries of the Spanish colonial period in Huarochirí (in the highlands east of Lima). I demonstrate how these activities were performative acts aimed at the conversion of space, which had implications for the conversion of the Andean past. Due to its unique Quechua manuscript, Huarochirí has been an epicenter both for studies of evangelization and for the reconstruction of the culture and history of the prehispanic and colonial indigenous world. However, the prevalence of ethnohistoric studies and the lack of systematic archaeology in the central axis of the manuscript’s composition has hindered deeper understandings of Huarochirí’s past and the different historicities employed in its reconstruction. Here history is combined with recent systematic archaeological research to provide a view of the different ways the past was understood, codified, and communicated in Huarochirí’s past–evident both in the material record and in the contents of the manuscript itself. The evidence presented challenges the prevalent ethnohistorical reconstruction of Huarochirí’s prehistory, demonstrating how both the contents and the very concept of history were converted as narrative sequences were conflated with historical sequences, obscuring culturally distinct forms of understanding, codifying, and communicating the past in the indigenous Andes. Additional archaeological and historical data provide a glimpse of an «Andean historicity».En este capítulo, considero la conversión religiosa de los indios como objetivo principal de la evangelización católica durante los primeros dos siglos de la Colonia en Huarochirí (sierra de Lima). Demuestro cómo estas actividades eran «presentaciones formales» dirigidas a la conversión del espacio y, por lo tanto, a la conversión del pasado andino (además de la conversión de la gente indígena misma). Debido a su manuscrito quechua de carácter único, Huarochirí ha sido un epicentro tanto del estudio de la evangelización como de la reconstrucción de la cultura e historia prehispánica y colonial. Sin embargo, la prevalencia de estudios etnohistóricos y la falta de investigaciones arqueológicas sistemáticas en el eje central de la composición del manuscrito han impedido una comprensión más profunda de la prehistoria de Huarochirí y sus modos de historicidad asociados. Aquí, se combina historia con arqueología sistemática recientemente hecha en Huarochirí para permitir una visión de ciertas características culturales del entendimiento, codificación y comunicación del pasado, tanto en el registro arqueológico como en el contenido del mismo manuscrito. Las evidencias presentadas desafían la reconstrucción (etno) histórica prevalente del pasado huarochirano, lo que demuestra cómo el contenido y el mismo concepto de la historia fueron convertidos cuando las secuencias narrativas fueron interpretadas como secuencias históricas, lo cual ha ofuscado formas culturalmente distintas de entender, codificar y comunicar el pasado en los Andes indígenas. Datos históricos y arqueológicos adicionales proveen vistas de una «historicidad andina».
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Dorsey, Andrew Hanson. "Pragmatic conversion: Hypocrisy and the mechanics of seventeenth-century Puritan conversion discourse". Diss., Connect to online resource, 2005. http://wwwlib.umi.com/dissertations/fullcit/3165828.
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McGever, Michael Sean. "Early evangelical conversion theology : John Wesley and George Whitefield's theologies of conversion". Thesis, University of Aberdeen, 2018. http://digitool.abdn.ac.uk:80/webclient/DeliveryManager?pid=237584.
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This thesis offers an examination of John Wesley and George Whitefield's theologies of conversion. The thesis is a work of historical theology which utilises the operant theologies of conversion present in these two figures in order to produce a work of espoused theology so as to state, in a way that has not previously been articulated systematically and directly, the theologies of conversion of Wesley and Whitefield. The argument of the thesis is that Wesley and Whitefield's theologies of conversion are best understood as an inaugurated teleology with an emphasis on the telos of salvation rather than the arché of salvation. The thesis argues that one can articulate nine synoptic statements of the espoused theology of conversion by attending to the operant theologies of conversion in the works of Wesley and Whitefield. First, conversion is initiated and sustained by the grace of God. Second, conversion is the experiential correlate to salvation. Third, conversion is a turning from self and to Christ. Fourth, conversion is foreshadowed by a deep sense of sinfulness. Fifth, conversion arrives by faith in an instant. Sixth, conversion is inaugurated instantaneously, but is not always recognisable on behalf of the convert. Seventh, conversion is marked by ongoing good works. Eighth, baptism marks one's entrance to the church but is not chronologically tied to conversion. And finally, ninth, assurance of salvation is available but not required for a genuine convert. It will be suggested that Wesley and Whitefield's accounts of conversion are both accurately understood in a summative way as inaugurated teleology. The thesis concludes with a summary of the argument, the contribution to knowledge, and by noting avenues for further study.
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Molloy, Mary Carmel. "Conversion select biblical characteristics with questions for discussion /". Theological Research Exchange Network (TREN), 1992. http://www.tren.com.
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Silva, Ubiravan Geraldo de Oliveira e. [UNESP]. "Análise energética em refino de petróleo". Universidade Estadual Paulista (UNESP), 2010. http://hdl.handle.net/11449/99282.
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silva_ugo_me_guara.pdf: 1310169 bytes, checksum: 03b83347690591e428c0b581f7931124 (MD5)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)
No trabalho apresentado foi realizada uma análise de eficiência energética levando em conta variáveis tais como a pressão, a temperatura, o estado físico dos componentes e a atividade de cada elemento que compõe a unidade de craqueamento em refino de petróleo. Tal análise foi realizada baseando-se na Primeira e Segunda leis da Termodinâmica. Destacou-se na análise do FCC a geração e a perda de energia com os gases, levando em conta a concentração molar de cada gás na entrada e na saída do FCC. No riser foram levadas em conta as transformações ocorridas e sua cinética com o propósito de fazer uma análise de gasto de energia no processo de formação inicial dos produtos do FCC; com isso, determinaram-se as quantidades de calor que foram utilizados no processo principal de formação. Foram realizadas análises sobre os fluxos de massas no vaso separador com a abordagem de um suposto fluxo interno, que seria a diferença entre as energias adquiridas com o vapor de retificação com os fluxos de carbono arrastados e com energia vinda do riser, e o fluxo de saída também para o processo de retificação no stripper. Verificou-se a energia gerada pelo regenerador e sua distribuição, que é feita com o aquecimento do catalisador na linha de transmissão do stripper e das perdas de energia com a troca do catalisador gasto e pela massa de catalisador que entra no riser. A energia perdida durante o processo foi associada à energia perdida na integralidade e em cada unidade. Verificou-se que uma parcela do calor gerado no processo é absorvida por gases inertes necessários ou integrados a gases reagentes; além disso, observou-se a formação de novos gases e compostos químicos que geram certas quantidades de energia, e que estão e são importantes na contabilização de toda energia que é gerada. Em tal análise levou-se em conta a energia de formação dos gases e a...
In the present study it was performed an analysis of energy efficiency taking into account variables such as pressure, temperature, physical state of the components and activities of each element that makes up a cracker in petroleum refining. The First and Second Law of Thermodynamics were used for the present analysis. It was highlighted in the analysis of the FCC the generation and loss of energy with the gases, taking into account the molar concentration of each gas at the inlet and outlet of the FCC. In the riser it was taken into account the transformations and their kinetics in order to make an analysis of energy use in the process of initial formation of the products of the FCC; with these results, it was determined the amounts of heat that were used in the main proceedings training. It was analyzed the flow of masses in the separator vessel with the approach of a supposed internal flow, which would be the difference between the energy gained steam with the rectification of carbon fluxes and dragged with energy coming from the riser, and the outflow also for the grinding process in stripper. There was the energy generated by the regenerator and its distribution, which is made by heating the catalyst in the transmission line striper and loss of energy with the exchange of spent catalyst and the mass of catalyst entering the riser. The energy lost during the process was associated with the energy that disappeared in the whole and in each unit. It was found that a portion of the heat generated is absorbed by inert gases necessary or integrated reactive gases; in addition, it was observed the formation of new gases and chemicals that generate amounts of energy, and are important in accounting for all energy that is generated. In this analysis it was taken into account the energy of formation of exhaust gases and the opportunities of products formation in the conditions ... (Complete abstract click electronic access below)
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Camilli, Coralie. "Messianisme, violence et conversion". Thesis, Paris Est, 2016. http://www.theses.fr/2016PESC0011.
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Notre recherche s’autorise d’une réflexion sur le messianisme continûment menée à partir des sources juives, essentiellement bibliques et talmudiques. Depuis cet indispensable point de départ, elle s’interroge centralement sur la possibilité d’une conversion de la violence en tout autre chose qu’elle-même, à savoir en droit, dès lors que celui-ci est entendu à la lumière du droit hé-braïque, c’est-à-dire ouvert sur son propre au-delà. Cette ouverture est ici comprise à partir du temps et de la loi, de leur relation. Car le juridique et le messianique s’entre-confortent, moyennant toute une série de mises au point et de clarifications quant à leurs temporalités propres. Le messianisme ap-paraît ainsi au fil de notre investigation comme un défi conceptuel par où tentent de s’articuler les particularités de l’existence historique, les exigences politiques et les promesses prophétiques. Il permet ainsi d’engager une ré-flexion originale et singulière sur l’Etat, la politique, l’histoire, les rapports entre le religieux et ses formes sécularisées, le droit et la vieOur thesis develops a reflection on the messianism continuously led from the Jewish, essentially biblical and talmudic sources. Since this essential starting point, we think here about the possibility of a conversion of the vio-lence in something quite different that itself, namely right or law, since this one is understood in the light of the Hebraic right, that is opened on his own beyond. This opening is understood here from time and law, from their rela-tion. Because the legal and the messianic enters consolidate, as a result of a whole series of clarifications and clarifications as for their appropriate tem-porality. The messianism so appears in our investigation as a theoretical challenge, which try to articulate the peculiarities of the historic existence, the political requirements and the prophetic promises. He so allows to have an original and singular reflection on State, politics, history, the relation-ships between religion and its secularized forms, right and life
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Vasi, Shiva. "Conversion to Zen Buddhism". Monash University, School of Political and Social Inquiry, 2004. http://arrow.monash.edu.au/hdl/1959.1/9601.
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Forget, Mario. "Conversion religieuse, libération humaine". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp04/nq25404.pdf.
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Kafka, John Anton (Tony). "Survey of childhood conversion". Theological Research Exchange Network (TREN), 1987. http://www.tren.com.
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Forsyth, A. J. "Switched-mode power conversion". Thesis, University of Cambridge, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.233948.
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The thesis begins with a general introduction to switched-mode power conversion. The main application areas of the technique are outlined and a summary is presented of current research work. The following chapters then focus on one recent development in the field, the Cuk converter and integrated magnetics. First, the steady-state performance limitations of the Cuk converter are explored through a comparison with the basic switched-mode converter topologies. The circuit is seen to possess several attractive properties including input and output current waveforms which are continuous rather than pulsating. However, the switching losses are shown to be high. A regenerative snubber is presented which reduces the transistor turn-off loss whilst preserving the high-quality input and output current waveforms of the converter. The integrated magnetics technique is discussed in the following chapter. This is the technique whereby converter magnetic components are coupled to eliminate input and output ripple currents and therefore improve steady-state performance. The possible problems are highlighted of attempting to couple transformers and inductors on a single core and an alternative coupling technique is outlined which uses an auxiliary electric circuit. The introduction of magnetic coupling in the Cuk converter to eliminate input and output ripple currents and improve steady-state performance results in more complicated dynamic characteristics and a more complex control problem. The state-space averaging technique is used in chapter 4 with the aid of a control engineering design package, CLADP, to analyse the problem. The impact of component coupling on the converter dynamic characteristics is explained and possible control strategies are suggested and verified. Finally, the Cuk converter with component coupling is assessed as a large-signal waveshaper. Several inverter configurations are examined in which a switched-mode converter operating under closed-loop control is used as a waveshaper to synthesise high-quality sinusoidal output currents. The implementation of the schemes using a Cuk converter with component coupling is described.
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Oki, Makanjuola. "Conversion coatings on aluminium". Thesis, University of Manchester, 1985. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.390302.
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Gerry, David Brian. "High voltage power conversion". Thesis, University of Nottingham, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.396620.
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McGury, Susan. "Primitivism and cultural conversion". Thesis, University of Reading, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.309516.
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Walker, Dane E. "Enhanced molybdate conversion coatings". Thesis, Loughborough University, 2013. https://dspace.lboro.ac.uk/2134/12209.
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The replacement of chromate conversion coatings for zinc coated components has been necessitated by the materials finishing industries due to the inherent toxicity issues with Cr(VI) and the legislative enforcement of WEEE and ELV Directives by the European Union. Current replacements are based on non-chromate , Cr(III) systems, these may be perceived by some to be problematic as they still contain chromium . Molybdate based conversion coatings have long been viewed by many researchers to be a viable non-chromium alternative due to their low toxicity. An extensive literature review of the research carried out in the last 20 years was carried out, highlighting areas of interest for improving the corrosion resistance of the coatings studied. These were, primarily, the synergesis that exists with molybdate and phosphate compounds for corrosion resistance and the incorporation of nanoparticle silica into treatment solution. Also discovered was the importance of the acid used to adjust treatment solution pH, immersion time, oxidising agent additions and the incorporation of rare earth metal species. Silicate sealant layers were also highlighted as a post treatment. Molybdate-based coatings were formed on commercial electrodeposited acid zinc surfaces. Many treatment conditions were investigated, and initially performance analysed using DC Linear Polarisation Resistance (LPR) trials. Subsequently, the highest performing coatings were subjected to the more aggressive, industry standard, ASTM B 117 Neutral Salt Spray (NSS) corrosion test. The highest performing molybdate coatings were found to have an average LPR of ~ 9 000 Ω. cm2, in contrast to ~ 12 000 Ω. cm2 for the Cr(VI) based reference. NSS results were amongst the highest performing for molybdate based coatings documented, at 24 h until 5% white rust, however remained inferior to Cr(VI) coatings, which lasted 120 h. The highest performing coatings were characterised using FEG-SEM, Cryofracture EDXA and site specific AES. These techniques revealed that the enhanced molybdate coatings had a columnar structure that was around 300 nm thick, with pores that appeared to expose the substrate. AES showed this type of coating to have a mixed Mo, P and Zn oxide surface. Corrosion initiation was also studied; this can be thought of as an investigation to determine the point(s) of weakness or the mechanism that causes coating failure. Coatings were immersed in 5 % wt/ vol NaCl(aq) until they showed any surface change. Initial signs of corrosion were deemed to be any appearance of pitting or discolouration of the film, not a voluminous corrosion product. Untreated Zn, Cr(VI) and simple molybdate coatings were studied as well as enhanced molybdate coatings. There were clear differences in the way the coatings behaved at the onset of corrosion. Cr(VI) coatings delaminated, leaving an area of decreased Cr concentration. The enhanced molybdate coatings failed by the appearance of localised pores of ~ 70 µm in diameter. Substrate exposure was indisputably the reason for coating failure in chloride environments. In light of the work carried out in the present thesis the outlook for the use of molybdate as a potential replacement for chromate for the conversion coating of electrodeposited zinc surfaces is a positive one.
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Lundin, Staffan. "Marine Current Energy Conversion". Doctoral thesis, Uppsala universitet, Elektricitetslära, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-280763.
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Marine currents, i.e. water currents in oceans and rivers, constitute a large renewable energy resource. This thesis presents research done on the subject of marine current energy conversion in a broad sense. A review of the tidal energy resource in Norway is presented, with the conclusion that tidal currents ought to be an interesting option for Norway in terms of renewable energy. The design of marine current energy conversion devices is studied. It is argued that turbine and generator cannot be seen as separate entities but must be designed and optimised as a unit for a given conversion site. The influence of support structure for the turbine blades on the efficiency of the turbine is studied, leading to the conclusion that it may be better to optimise a turbine for a lower flow speed than the maximum speed at the site. The construction and development of a marine current energy experimental station in the River Dalälven at Söderfors is reported. Measurements of the turbine's power coefficient indicate that it is possible to build efficient turbines for low flow speeds. Experiments at the site are used for investigations into different load control methods and for validation of a numerical model of the energy conversion system and the model's ability to predict system behaviour in response to step changes in operational tip speed ratio. A method for wake measurements is evaluated and found to be useful within certain limits. Simple models for turbine runaway behaviour are derived, of which one is shown by comparison with experimental results to predict the behaviour well.
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Kovalenko, A. "Conversion in modern English". Thesis, Sumy State University, 2016. http://essuir.sumdu.edu.ua/handle/123456789/49160.
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Nowadays the number of conversion is extremely increasing, so it is very important to examine some new trends of conversion. 100 conversions selected from the Internet were the material for our research. To study conversion of new trends we conducted their quantitative analysis.
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Hults, Christopher S. "Shakespeare's Cultural Capital Conversion". BYU ScholarsArchive, 2019. https://scholarsarchive.byu.edu/etd/7736.
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Shakespeare's vast cultural capital does not often translate easily to financial capital.Whether those who invest in Shakespeare seek financial, educational, or cultural gain, anunderstanding of capital conversion as it relates to Shakespeare industries can inform decisionsand clarify goals. After clarifying and delineating what we have and know of Shakespeare before1616 and what has been created by culture regarding him after 1616, we label the latterShakesaltation, then seek the key to converting his cultural capital to financial capital. ApplyingPierre Bourdieu's states of cultural capital to the Shakespeare industry illustrates why manyinvestments fail, few succeed, and why: cultural capital must be in its institutionalized state inorder to be convertible to profit. Juxtaposing three case studies of Shakespeare industries (Film,Cultural Destination Tourism, and the Bard Branding practice in various industries), analyzedusing Bourdieu, confirms that Shakesaltation — the ideals and myths that have been createdaround Shakespeare beyond his death — are the key to profiting from Shakespeare.
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Brukner, Jan. "Non-Parallel Voice Conversion". Master's thesis, Vysoké učení technické v Brně. Fakulta informačních technologií, 2020. http://www.nusl.cz/ntk/nusl-417207.
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Cílem konverze hlasu (voice conversion, VC) je převést hlas zdrojového řečníka na hlas cílového řečníka. Technika je populární je u vtipných internetových videí, ale má také řadu seriózních využití, jako je dabování audiovizuálního materiálu a anonymizace hlasu (například pro ochranu svědků). Vzhledem k tomu, že může sloužit pro spoofing systémů identifikace hlasu, je také důležitým nástrojem pro vývoj detektorů spoofingu a protiopatření. Modely VC byly dříve trénovány převážně na paralelních (tj. dva řečníci čtou stejný text) a na vysoce kvalitních audio materiálech. Cílem této práce bylo prozkoumat vývoj VC na neparalelních datech a na signálech nízké kvality, zejména z veřejně dostupné databáze VoxCeleb. Práce vychází z moderní architektury AutoVC definované Qianem et al. Je založena na neurálních autoenkodérech, jejichž cílem je oddělit informace o obsahu a řečníkovi do samostatných nízkodimenzionýálních vektorových reprezentací (embeddingů). Cílová řeč se potom získá nahrazením embeddingu zdrojového řečníka embeddingem cílového řečníka. Qianova architektura byla vylepšena pro zpracování audio nízké kvality experimentováním s různými embeddingy řečníků (d-vektory vs. x-vektory), zavedením klasifikátoru řečníka z obsahových embeddingů v adversariálním schématu trénování neuronových sítí a laděním velikosti obsahového embeddingu tak, že jsme definovali informační bottle-neck v příslušné neuronové síti. Definovali jsme také další adversariální architekturu, která porovnává původní obsahové embeddingy s embeddingy získanými ze zkonvertované řeči. Výsledky experimentů prokazují, že neparalelní VC na nekvalitních datech je skutečně možná. Výsledná audia nebyla tak kvalitní případě hi fi vstupů, ale výsledky ověření řečníků po spoofingu výsledným systémem jasně ukázaly posun hlasových charakteristik směrem k cílovým řečníkům.
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Martins, Jose Endoença. "A politics of conversion". Florianópolis, SC, 2002. http://repositorio.ufsc.br/xmlui/handle/123456789/82730.
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Tese (doutorado) - Universidade Federal de Santa Catarina, Centro de Comunicação e Expressão. Programa de Pós-Graduação em Letras.Made available in DSpace on 2012-10-19T17:48:13Z (GMT). No. of bitstreams: 0Bitstream added on 2014-09-26T02:23:07Z : No. of bitstreams: 1 183607.pdf: 6591745 bytes, checksum: 0ccb91ca51229495b5f5d1bd81ab1f0f (MD5)
O estudo Uma Política de Conversão: Niilismo e Amor na Ficção de Toni Morrison começa com a idéia de que a Literatura Afro-Americana apresenta um sentido de auto-reflexividade e hibridismo, através do qual autobiografia dialoga com romance, o espiritual se funde com o político. A partir deste traço dialógico a auto-reflexividade é politicamente estabelecida entre niilismo e amor. Na política de conversão, o estudo analisa as formas como mulheres negras, individualmente ou em grupo, fogem da escravidão para a liberdade, avançam da individualidade para a coletividade, ou substituem niilismo por amor. Metodologicamente o estudo apresenta sete capítulos. O primeiro discute os aspectos dialógicos que ilustram as conexões entre narrativas espirituais, de escravos e ficção, entre espiritualidade e política. O segundo examina o diálogo entre a conversão, pregação pública e formação da comunidade em Diário e Experiências Religiosas de Lee. O capítulo sugere que ao afirmar espiritualidade e humanidade a narradora abre profundo espaço para a mulher negra reclamar direitos civis. O terceiro discute o diálogo no interior da política de conversão entre narrativa de escravos e ficção. Este diálogo lida com niilismo e amor em Incidentes de Jacobs e Amada, Sula e O Olho Mais Azul de Morrison. Para a análise de niilismo e amor valores individuais e coletivos são considerados em relação a cinco aspectos: ambiente e agente antagonistas, agente de apoio, propósito da personagem e resultado alcançado. É visível, no estudo, o apoio que certas mulheres recebem de suas comunidades para contra-atacar antagonistas. O apoio nem sempre resulta na superação do niilismo e, por isso, derrota temporária pode ocorrer antes que elas sejam reintegradas à comunidade, como acontece com Linda Brent. O quarto capítulo examina as fraquezas e as energias da política da conversão e a reintegração de Sethe Suggs à comunidade de Bluestone Road. O quinto avalia como a comunidade de Bottom tenta controlar a individualidade de Sula Peace e como um grupo de mulheres lideradas por Nel Wrights consegue resgatar o espírito de independência da heroína. O sexto mostra como a política da conversão das mulheres de Lorain é incapaz de garantir a saúde mental de Pecola Breedlove, mas consegue criar um papel mais consistente para o grupo. No sétimo, a conclusão examina da relação dialética entre niilismo e amor ou auto-amor nas experiências dos indivíduos e dos grupos. O estudo sugere que em Incidentes a busca de Linda Brent por liberdade envolve elementos de autodestruição e de autoempoderamento. Da mesma maneira, o estudo conclui que em Amada o amor que Sethe Suggs tem para as suas crianças mata a própria filha, enfatizando, assim, o desejo de livrá-la da escravidão. Igualmente em Sula, a individualidade de Sula Peace não apenas limita, mas também expande as experiências do grupo, levando-o à emancipação. Finalmente, em O Olho Mais Azul a luta de Pecola Breedlove por amor e beleza reflete auto-ódio ao mesmo tempo em que reconstrói a auto-apreciação de toda a comunidade.
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Crook, Zeba A. "Reconceptualising conversion : patronage, loyalty, and conversion in the religions of the ancient Mediterranean /". Berlin [u.a.] : de Gruyter, 2004. http://www.loc.gov/catdir/toc/fy0611/2004471591.html.
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Bonté, Rosalind Suzanne. "Conversion and coercion : cultural memory and narratives of conversion in the Norse North Atlantic". Thesis, University of Cambridge, 2015. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.708971.
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Silva, Ubiravan Geraldo de Oliveira e. "Análise energética em refino de petróleo /". Guaratinguetá : [s.n.], 2010. http://hdl.handle.net/11449/99282.
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Resumo: No trabalho apresentado foi realizada uma análise de eficiência energética levando em conta variáveis tais como a pressão, a temperatura, o estado físico dos componentes e a atividade de cada elemento que compõe a unidade de craqueamento em refino de petróleo. Tal análise foi realizada baseando-se na Primeira e Segunda leis da Termodinâmica. Destacou-se na análise do FCC a geração e a perda de energia com os gases, levando em conta a concentração molar de cada gás na entrada e na saída do FCC. No riser foram levadas em conta as transformações ocorridas e sua cinética com o propósito de fazer uma análise de gasto de energia no processo de formação inicial dos produtos do FCC; com isso, determinaram-se as quantidades de calor que foram utilizados no processo principal de formação. Foram realizadas análises sobre os fluxos de massas no vaso separador com a abordagem de um suposto fluxo interno, que seria a diferença entre as energias adquiridas com o vapor de retificação com os fluxos de carbono arrastados e com energia vinda do riser, e o fluxo de saída também para o processo de retificação no stripper. Verificou-se a energia gerada pelo regenerador e sua distribuição, que é feita com o aquecimento do catalisador na linha de transmissão do stripper e das perdas de energia com a troca do catalisador gasto e pela massa de catalisador que entra no riser. A energia perdida durante o processo foi associada à energia perdida na integralidade e em cada unidade. Verificou-se que uma parcela do calor gerado no processo é absorvida por gases inertes necessários ou integrados a gases reagentes; além disso, observou-se a formação de novos gases e compostos químicos que geram certas quantidades de energia, e que estão e são importantes na contabilização de toda energia que é gerada. Em tal análise levou-se em conta a energia de formação dos gases e a ... (Resumo completo, clicar acesso eletrônico abaixo)Abstract: In the present study it was performed an analysis of energy efficiency taking into account variables such as pressure, temperature, physical state of the components and activities of each element that makes up a cracker in petroleum refining. The First and Second Law of Thermodynamics were used for the present analysis. It was highlighted in the analysis of the FCC the generation and loss of energy with the gases, taking into account the molar concentration of each gas at the inlet and outlet of the FCC. In the riser it was taken into account the transformations and their kinetics in order to make an analysis of energy use in the process of initial formation of the products of the FCC; with these results, it was determined the amounts of heat that were used in the main proceedings training. It was analyzed the flow of masses in the separator vessel with the approach of a supposed internal flow, which would be the difference between the energy gained steam with the rectification of carbon fluxes and dragged with energy coming from the riser, and the outflow also for the grinding process in stripper. There was the energy generated by the regenerator and its distribution, which is made by heating the catalyst in the transmission line striper and loss of energy with the exchange of spent catalyst and the mass of catalyst entering the riser. The energy lost during the process was associated with the energy that disappeared in the whole and in each unit. It was found that a portion of the heat generated is absorbed by inert gases necessary or integrated reactive gases; in addition, it was observed the formation of new gases and chemicals that generate amounts of energy, and are important in accounting for all energy that is generated. In this analysis it was taken into account the energy of formation of exhaust gases and the opportunities of products formation in the conditions ... (Complete abstract click electronic access below)
Orientador: José Antonio Perrella Balestieri
Coorientador: Rubens Alves Dias
Banca: Luiz Roberto Carrocci
Banca: Luciano Fernando dos Santos Rossi
Mestre
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Zhao, Yixin. "Developing Nanomaterials for Energy Conversion". Cleveland, Ohio : Case Western Reserve University, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=case1270172686.
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Krufka, Stephen Edward. "Visual to tactile conversion theory". Access to citation, abstract and download form provided by ProQuest Information and Learning Company; downloadable PDF file 0.79 Mb., 82 p, 2006. http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&res_dat=xri:pqdiss&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&rft_dat=xri:pqdiss:1435831.
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Laestander, Joakim, i Simon Laestander. "OTEC - Ocean Thermal Energy Conversion". Thesis, KTH, Energiteknik, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-98974.
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OTEC is a technology where power is produced by utilizing the temperature difference in the oceans between surface water and water from the deep. It is considered that a temperature difference of 20K is required – a temperature difference found close to the equator.This report investigates if OTEC can produce enough electricity to provide 100 000 people, living on a generic island of 10 km2 somewhere alongside the equator in the pacific ocean, with their electricity needs. In this project a literature review has been made to establish a basic knowledge of OTEC and later a mathematical model has been programmed and simulated. Finally the results of the simulation has been examined and discussed.Two different cycles has been simulated alongside each other with the goal to establish which one of these two cycles that were best suited the island. To facilitate computing some assumptions and simplifications were made.The closed cycle (CC) was the most effective but the open cycle (OC) had several positive synergies that the closed cycle didn’t have. The costs of a facility of both cycles were based on older studies in the field and the conclusion was that the open cycle was the cheaper one. Facilities of both cycles can effectively meet the islands energy needs but if OC is chosen before CC more facilities has to be built due to the OC has lower energy output.Further work and development is necessary before OTEC seriously can challenge todays fossil fuel based energy systems, or until the oil starts to get too expensive. Today OTEC technology demands large investments but if the positive environmental effects and the fact that the island releases itself from import of energy are taken into account there are incentives to invest in OTEC already.OTEC är en teknik där kraft utvinns från havsvatten genom att utnyttja temperaturdifferensen mellan ytvatten och vatten från djupet. Denna teknik kräver dock generellt en temperaturdifferens på minst 20K. En sådan temperaturskillnad är geografiskt begränsad till den tropiska zonen runt ekvatorn.I rapporten undersöks om OTEC kan användas till att förse 100 000 människor, boende på en 10 stor generisk ö i just den tropiska zonen, med dess elbehov. I detta projekt har det gjorts en litteraturstudie för att etablera en kunskapsbas och sedan gjorts en matematisk modell i programmet EES och slutligen har resultaten från modellen granskats och diskuterats. I modellen jämfördes två olika cykler och målet var att bestämma vilken av dessa som var det bästa alternativet för ön. För att underlätta beräkningarna gjordes vissa antaganden och förenklingar.Den slutna cykeln var mest effektiv men den öppna cykeln (OC) hade positiva synergieffekter som den sluta cykeln (CC) saknade. Kostnaden för en anläggning baserades på äldre studier och enligt dessa var den öppna cykeln billigare än den slutna. Anläggningar av de båda cyklerna kan tillgodose den fiktiva öns energibehov, det behöver dock byggas fler anläggningar om OC väljs framför CC.Det kommer krävas ytterligare arbete med att utveckla tekniken innan OTEC på allvar kan utmana dagens fossilbränslebaserade energisystem – eller att oljan helt enkelt blir för dyr. Idag är OTEC för dyrt för att kunna motiveras rent ekonomiskt, men om även miljövinsterna beaktas, samt att ön befriar sig från importer och därigenom får större kontroll över sitt eget energisystem, finns goda incitament att investera i OTEC redan idag.
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Lavery, Jonathan Allen. "Education, conversion and Plato's Protagoras". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk2/tape15/PQDD_0027/NQ31886.pdf.
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Aitken, Wendy Ann Jewkes. "Storytelling and conversion in children". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2001. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp05/MQ64035.pdf.
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Saucier, Scott. "Multiband Analog-to-Digital Conversion". Fogler Library, University of Maine, 2002. http://www.library.umaine.edu/theses/pdf/SaucierS2002.pdf.
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Rajagopal, Murali. "Protocol conversion : an algorithmic approach". Diss., Georgia Institute of Technology, 1990. http://hdl.handle.net/1853/13352.
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Ho, Ching-Hsiang. "Speaker modelling for voice conversion". Thesis, Brunel University, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.365076.
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Ashcroft, Alexander T. "Methane conversion over oxide catalysts". Thesis, University of Oxford, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.305983.
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Etheridge, Andrea Mary. "Conversion coatings on aluminium alloys". Thesis, University of Oxford, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.307051.
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Rentzos, Dimitrios. "Speaker modelling for voice conversion". Thesis, Brunel University, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.483558.
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Smith, Neville Stuart. "A colour notation conversion program". Thesis, Teesside University, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.279428.
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MacDonald, Paul S. "Descartes, Husserl and radical conversion". Thesis, Durham University, 1996. http://etheses.dur.ac.uk/5244/.
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Phenomenology has been one of the most influential and far-reaching developments in 20th Century Philosophy and has had a great impact on the disciplines of philosophy of logic and math, theory of knowledge, and theory of meaning. The most profound influence on Edmund Husserl (1859 - 1938), the founder of phenomenology, was Rene Descartes (1596 - 1650), whose radical rethinking of philosophy’s overall project provided Husserl with both the historical and conceptual point of departure for his foundation of prima philosophia. Despite this explicit and well-known influence, there is no book- length study of their thematic parallels; numerous Journal articles focus almost entirely on the phenomenological reduction and, aside from this, are fairly unsatisfactory. The purpose of the present work is to elucidate systematic convergences (and divergences) between Descartes and Husserl throughout their respective philosophical developments. This comprises explication of several central topics: 1. The parallel between 17th C. skepticism, which Descartes attempted to overthrow, and 19th C. psychologism and relativism, which Husserl reacted against. 2. The striking similarity at the level of formal ontology between Descartes' simple and complex natures and Husserl's part-whole theory. 3. A clarification of the Cartesian sense of methodical doubt and how Husserl's mistaking of this shaped the initial formulation of the reduction. 4. Convergence in the maturation of the primitive notion of intuition as "clear and distinct seeing" and "seeing of essences" for both thinkers. 5. An analysis of the modes of methodical doubt, in terms of steps in the cognitive act of doubting, and not merely in the content of that which is doubted. 6. Far-reaching divergences in that Descartes was motivated to establish with scientific certainly an entirely new world of being, whereas Husserl was concerned to disclose an entirely new sense of the world. As such, thematic convergences between Descartes and Husserl are not due to accidental intersections of interest, nor are they curiosities of the comparative method in historical research. These parallels are intrinsic and systematic due to an overarching congruence in their visions of the starting point, methodological procedures, and reaction to pseudo-scientific matters-of-fact in the founding of a genuine philosophical project.
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Xu, Shaojun. "Plasma-assisted conversion of CO2". Thesis, University of Manchester, 2017. https://www.research.manchester.ac.uk/portal/en/theses/plasmaassisted-conversion-of-co2(19c87dfa-ba79-47ea-a63d-0a0026a03bba).html.
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The transformation of carbon dioxide into added value chemicals by a plasma-activated catalytic process was studied. First of all, the current status of CO2 reutilisation by plasma-assisted technologies was reviewed. Followed by an in-depth study on the process of plasma-catalysis, the effects of dilution gas (i.e. argon and nitrogen) addition and operating parameters in CO2 dissociation were systematically investigated in non-thermal atmospheric pressure plasma barium titanate (BaTiO3) packed-bed reactor from both an engineering and scientific point of view. The extensive experimental and modelling study provided an insight into the relationship between the operating parameters, plasma electrical properties and electron-induced reaction processes in the discharge and the effect of the dilution gases on the product formation and reaction mechanism. The results showed that there was a higher CO2 conversion and energy efficiency in the studied packed-bed reactor than the dielectric barrier discharge (DBD) reactor with and without packed materials using electrodes covered by dielectric layers. Based on the above research work, an in-depth study of the complex mechanism of plasma-catalysis interface reaction was carried out. A new model catalyst (Ni/α-Al2O3 nanocatalyst) with a minimum of physical and chemical variables was specifically designed and synthesised for plasma-assisted reactions to help directly understand the intrinsic role of catalytic active sites during the plasma-catalytic process. In situ time-resolved tuneable lead salt diode laser (TDL) diagnostics of carbon dioxide decomposition over the model catalysts in a planar dielectric barrier discharge (DBD), non-thermal atmospheric pressure plasma reactor demonstrated that the active Ni metal sites do enhance the plasma-catalytic reaction in a similar way as that in conventional catalytic processes. Finally, demonstration of a novel catalysis concept of in situ capture-catalytic system was made for the plasma-assisted catalytic water gas shift reaction. This was investigated in a barium titanate (BaTiO3) packed-bed, non-thermal atmospheric pressure plasma reactor operating at 298 K. The results showed that the packed-bed reactor with CuBTC metal-organic framework (MOF) addition enhanced the CO conversion up to 43%. The comprehensive characterisation of the CuBTC MOF shows that CuBTC MOF exhibited sustainably good physical and chemical stabilities during 4 h long term continuous plasma reaction. The research work in this thesis showed that the BaTiO3 ferroelectric, packed-bed, non-thermal plasma reactor is a potential and powerful environmental solution for CO2 dissociation and other similar pollution treatments with a much higher conversion and energy efficiency at a high specific input energy, more mature and cheaper reactor configuration to scale-up without the need for dielectric barriers. As catalyst introduced into the plasma-assisted process, the demonstrated similar catalytic role of catalytic active sites in plasma-catalytic processes as in conventional thermal catalytic processes opened the gate to apply the catalysts and basic catalytic theories in conventional thermal catalysis field into the non-thermal and atmospheric plasma processes. The boundary of catalysis has been further extended, especially for the non-thermal atmospheric catalytic processes. The catalysis concept for the combination of plasma-catalytic process and conventional thermal catalytic process to enhance the adsorption process of the reactant and then catalyse it simultaneously over the active sites at room temperature and atmospheric pressure could be realised, as demonstrated by using the MOFs with a large gas capture capacity to catalyse water gas shift reaction in non-thermal atmospheric plasma.
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Chin, Timothy Edward. "Electrochemical to mechanical energy conversion". Thesis, Massachusetts Institute of Technology, 2010. http://hdl.handle.net/1721.1/63015.
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Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Materials Science and Engineering, 2010.Cataloged from PDF version of thesis.
Includes bibliographical references.
Electrode materials for rechargeable lithium ion batteries are well-known to undergo significant dimensional changes during lithium-ion insertion and extraction. In the battery community, this has often been looked upon negatively as a degradation mechanism. However, the crystallographic strains are large enough to warrant investigation for use as actuators. Lithium battery electrode materials lend themselves to two separate types of actuators. On one hand, intercalation oxides and graphite provide moderate strains, on the order of a few percent, with moderate bandwidth (frequency). Lithium intercalation of graphite can achieve actuation energy densities of 6700 kJ m-3 with strains up to 6.7%. Intercalation oxides provide strains on the order of a couple percent, but allow for increased bandwidth. Using a conventional stacked electrode design, a cell consisting of lithium iron phosphate (LiFePO4) and carbon achieved 1.2% strain with a mechanical power output of 1000 W m 3 . Metals, on the other hand, provide colossal strains (hundreds of percent) upon lithium alloying, but do not cycle well. Instead, a self-amplifying device was designed to provide continuous, prolonged, one-way actuation over longer time scales. This was still able to achieve an energy density of 1700 kJ n 3, significantly greater than other actuation technologies such as shape-memory alloys and conducting polymers, with displacements approaching 10 mm from a 1 mm thick disc. Further, by using lithium metal as the counterelectrode in an electrochemical couple, these actuation devices can be selfpowered: mechanical energy and electrical energy can be extracted simultaneously.
by Timothy Edward Chin.
Ph.D.
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Le, François Josette. "La conversion chez Thomas Merton". Mémoire, Université de Sherbrooke, 2001. http://savoirs.usherbrooke.ca/handle/11143/5193.
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Cette recherche visait à approfondir la réalité de la conversion chez Thomas Merton. Je l'ai développée autour de l'hypothèse suivante: la vision de la conversion chez Merton permet de mieux cerner cette réalité, elle en renouvele la saisie pour aujourd'hui. J'espérais ainsi renouveler la façon d'aborder cette réalité centrale de la vie chrétienne. Cinq questions m'ont guidée: Qu'est-ce qui caractérise la conversion chez Merton et la rend nécessaire? Qu'elles en sont les conditions, les obstacles et les fruits? Qu'elle en est la part qui revient à Dieu et à l'humain? J'y ai fait trois découvertes: (1) Merton articule sa réflexion autour de Mc 8 34, (2) il la développe en faisant appel simultanément aux langages de la Bible, de la Tradition monastique, de la vie mystique et de la psycho/psychanalyse, (3) il privilégie la"prière du coeur" comme moyen.
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Clark, Joanna Helen. "Inorganic materials for energy conversion". Thesis, University of Liverpool, 2011. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.569768.
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In an effort to design systems that harvest solar light and convert this into chemical energy, the primary aim of the work presented in this thesis was to develop complex metal oxide materials that were active photocatalysts under visible light. The existing methods for visible light incorporation into photocatalytically active materials are reviewed. Of these, metal to metal charge transfer (MMCT) between bimetallic surface- grafted assemblies was taken as particular inspiration. It was hypothesised that MMCT between metal centres within a bulk complex metal oxide could be similarly applied to yield photocatalytic ally active charge carriers. This approach takes advantage of the stability of bulk systems and the ability to tune the compositions of complex oxide materials. Moreover, it was proposed that MMCT between metal centres located on crystallographically distinct sites of a bulk material would aid charge separation and migration throughout the extended lattice. The optical properties of the RE2 Ti207 (RE = Y, La, Ce, Pr) and Ba2XTizM3015 (X = La, Ce, Pr, Nd, Bi; M = Nb, Ta) series, which include some novel cerium(III) titanates, revealed systematic changes in the electronic structures of these materials. These were rationalised with respect to the energy of Ln 4f states. The proposed electronic structures present the partial achievement of the bulk MMCT hypothesis, with optical transitions from occupied Ce 4f midgap states to the unoccupied primarily Ti 3d conduction band. These Ce3+ /rr" charge transfer materials were inactive photocatalysts, attributed to the presence the Ce 4f-based midgap states that facilitate charge recombination. The double perovskite CaCu3T40IZ, with A-site Cu2+ and B-site Ti4+ cations and whose dielectric properties have been studied extensively in the past, is an ideal candidate for the two site MMCT strategy. Here, the optical and photocatalytic properties, rationalised with the aid of DFT calculations, present the partial achievement of the bulk MMCT hypothesis. Sol-gel derived Pt-CaCu3 Ti4012 is an active photocatalyst toward the visible light photo-oxidation of model pollutants methyl orange (MO) and 4-chlorophenol (4CP). Optical spectra and product analysis show that these reactions proceed via more selective routes than the typical reaction over TiOz P25 under DV light. Interestingly, the products of 4CP photo-oxidation were shown to be dependent on the wavelength of incident light. Cu-doping of BizTiz07 was found to stabilise the pyrochlore structure with respect to the Aurivillius phase Bi4 Ti3012 and to impart significant visible light absorption. Sol-gel derived Pt-BiI.6Cuo.4 Tiz07 photo-oxidised MO under visible light via conventional band gap excitation, as determined by quantum efficiency measurements. In contrast, sol-gel derived Pt-B4 Ti3012 photo-oxidised MO via the excitation of adsorbed MO, and was also active toward 4CP photo-oxidation under visible light. The excitation method, mechanisms and product distributions have been investigated for each of the photo-oxidation reactions presented in this thesis. In particular, the photo- oxidation of MO over some Pt-modified metal oxides has been shown to proceed via excitation of adsorbed MO and not of the semiconductor. Additionally, the mechanism and products of these processes are far more selective than the related DV reactions over TiOz P25, and have been shown to depend to some extent on the semiconductor support.
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de, Albuquerque Fragoso Danielle Munick. "Lignin conversion to fine chemicals". Thesis, University of Glasgow, 2018. http://theses.gla.ac.uk/30847/.
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The large availability of Kraft lignin as an industrial by-product and its polyaromatic characteristic, is ideal to consider the potential for recycling it into fine chemicals. To depolymerise lignin, solvolysis and hydrogenolysis experiments were performed. This research considered whether the low yields of products (fine chemicals) were related to the low content of β-O-4 bonds or if it was also associated to the dissolution of lignin in the solvent solution employed in the reactions. The type of solvents chosen to check the dissolution effect were those with low cost and were more sustainable than traditional solvents. Water, ethanol, isopropanol (IPA) and acetone were used. The water mixtures were applied in the tests in various proportions (25:75, 50:50, 75:25 solvent/water v:v). Due to their ability to break C-C and C-O bonds in lignin model compounds [1][2], the efficiency of platinum and rhodium in these reactions supported on alumina was also studied. It was found that the non-catalysed (solvolysis) and catalysed reactions showed different selectivities but similar overall yields ~ 10 % wt of monomeric phenols. The difficulty in increasing yields was mainly associated with the highly condensed character of Kraft lignin and re-polymerisation issues. To achieve an understanding of Kraft lignin depolymerisation, isotopic labelling reactions were completed in the presence of deuterated solvents as well as deuterium gas. This gave information on how Kraft lignin depolymerises, the influence of solvent to products formation and the involvement of hydrogen in the rate determining steps in the reactions. These results have led to an initial mechanistic understanding on how this complex molecule may yield alky-phenolic compounds. It was revealed that the solvent was directly involved in the products’ formation and that they were not generated by simple thermolysis. In addition, the presence of catalysts and hydrogen influenced product formation. The compounds showed different kinetic isotopic values, suggesting that each of these molecules came from individual mechanisms, highlighting the complexity of their formation. This was a relevant study as most of lignin depolymerisation mechanistic insights are based on model compounds and not on lignin itself. It was of interest to this project to explore not only different catalysts and their relationship to lignin depolymerisation, but also different lignin types. A simple pre-treatment for lignin extraction using sawdust (from oak and birch wood) in a Parr autoclave reactor in the presence of hydrogen, solvent and high temperature was developed. The lignins obtained after the pre-treatment were named parr-lignin and successfully resulted in polyaromatic molecules with less condensed character compared to lignins from Soda or Kraft pulping. Reactions were carried out with these lignins and a sugar-cane lignin. 4 5 Different catalytic systems with these lignins were investigated and how depolymerisation was affected by the metal and support used. The catalysts involved in the reactions included platinum, rhodium, nickel and iron. Various supports such as alumina, zirconia and carbon were tested along with the metals described. It was found that the supports were not inert in these experiments presenting catalytic activity. Materials with low surface area (zirconium catalysts) gave a poor performance compared to the others. In addition, nickel, a non-noble metal, showed as good a catalytic effect in the depolymerisation of these lignins as Pt and Rh. The components in the system influenced the reactions to different extents, especially product distribution. The catalysts had different selectivities and the solvents were not only dissolving lignin but also influencing the results. GPC analysis was performed to give an overview of the condensed level of these lignins and degrees of depolymerisation compared to the original material. GC-MS enabled the identification and quantification of 18 monomeric compounds. The post reaction characterisation of selected alumina catalysts (Pt/Al2O3, Ni/Al2O3 and Al2O3) was performed using XRD, BET, CHN, TPO and Raman Analysis to study the nature of the carbonaceous layer deposited on these materials. The work showed that after reaction the catalysts turned black in colour and the carbon laydown consisted of not only one simple type of carbon, and included graphitic species. The amount of carbon deposited depended on the type of lignin. Oak and birch parr-lignins had the highest and lowest amount of carbon over the catalysts respectively. No obvious trend relating to the type of catalyst, lignin and solvent used to the carbon nature was identified. This work showed that lignins with less condensed nature were less susceptible to solvolysis and more to hydrogenolysis. For example, sugar-cane lignin gave 3.9% of phenolic compounds in the solvolysis while reaction with Rh/Al2O3 gave 12.9% of products. This indicated that more selective cleavage of bonds were promoted by heterogenous catalysts. The results suggested that some compounds were mainly generated via dealkylation and hydrodeoxygenation, allowing a future possibility to generate target molecules. These results were mainly due to the presence of more labile bonds, vulnerable to hydrogenolysis. Highlighting that prior to depolymerisation, the pre-treatment used to extract lignin must be appropriate to avoid depletion of the alkyl-aryl ether bonds (β-O-4 bonds, especially) relevant for fine chemicals generation.
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Costa, Bárbara Reis da. "Cash conversion cycle across industries". Master's thesis, NSBE - UNL, 2014. http://hdl.handle.net/10362/11731.
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A Work Project, presented as part of the requirements for the Award of a Masters Degree in Management from the NOVA – School of Business and EconomicsThe purpose of this research is to assess whether Cash Conversion Cycle differs between industries via their components, namely Days Inventory Outstanding, Days Sales Outstanding and Days Payables Outstanding. Based on a sample of multinational companies from two different industries, Fast Moving Consumer Goods and Airline industry for the period 2009-2012, the results suggest that Cash Conversion Cycle differs between industries. Also it differs between large and smaller companies due to different accounting choices. It contributes to a better understanding about how size of the firm, inventory system, liquidity and payables impact on CCC and consequently on companies’ profitability.