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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.
321

At home in the journey a process of theological reflection for missioners in transition /

McCaffrey, Jo Ann, January 1998 (has links)
Thesis (D. Min.)--Catholic Theological Union at Chicago, 1998. / Abstract and vita. Includes bibliographical references (leaves 222-229).
322

Switching converter techniques for energy harvesting applications /

Sze, Ngok Man. January 2007 (has links)
Thesis (M.Phil.)--Hong Kong University of Science and Technology, 2007. / Includes bibliographical references (leaves 93-95). Also available in electronic version.
323

The role of community and culture in spiritual growth for individuals who are converts to Buddhism

Lienau, Amanda Marie, January 2007 (has links)
Thesis (Ph. D.)--Ohio State University, 2007. / Title from first page of PDF file. Includes bibliographical references (p. 137-141).
324

In search of meaning and identity : conversion to Christianity in Pakistani Muslim culture /

Syrjänem, Seppo. January 1984 (has links)
Th.--Théol.--Helsinki, 1984. / Bibliogr. pp. 232-246. Glossaire pp. 228-229.
325

Das Weltleben und die Bekehrung der Maria Magdalena im deutschen religiösen Drama und in der bildenden Kunst des Mittelalters /

Van Den Wildenberg-De Kroon, Cornelia Elizabeth Catharina Maria. January 1979 (has links)
Proefschrift--Letteren--Amsterdam, 1979. / La couverture porte le nom "Conny Van den Wildenberg-de Kroon" Résumés en néerlandais, en français et en anglais. Bibliogr. p. 114-128.
326

Simulation d'une unité de dessalement par thermocompression : couplage avec des capteurs d'énergie solaire.

Gros, Bernard, Unknown Date (has links)
Th. doct.-ing.--Génie chimique--Toulouse--I.N.P., 1983. N°: 289.
327

Development, optimization and implementation of the design for a centrifugal reverse-osmosis desalination system

Wild, Peter Martin 19 June 2018 (has links)
A new method of sea water desalination, Centrifugal Reverse-Osmosis (CRO), is developed from concept to patented design and functional prototype of capacity 11,355 litres of fresh water per day. CRO is shown to have significant benefits relative to the leading existing desalination technology, conventional reverse-osmosis. These benefits include: lower energy consumption, reduced initial and replacement membrane costs, lower noise levels and improved reliability. CRO is projected to show increasing cost efficiency as plant capacity increases. For a relatively large CRO plant, 65lm³ fresh water per day, the total cost of desalinated water is projected to be 25.9% lower than the total cost of water produced by a conventional RO plant of equivalent capacity. The current patented design requires further development in order to realize this potential. Toward this end, a computational and experimental study of rotor windage losses and an experimental study of fluid flow losses through the rotor are conducted. In addition a new method for the analysis of stresses in a filament wound rotor shell under combined centrifugal and pressure loading is developed. / Graduate
328

Nouvelles structures de conversion multi-cellulaires à base des transistors GaN pour la conversion DC-DC : applications au conditionnement des énergies renouvelables. / New structures of multi-cellular conversion based on GaN transistors for DC-DC conversion : conditioning in renewable energies applications.

Sarrafin ardebili, Farshid 28 March 2017 (has links)
Dans le but de gérer la consommation et ainsi que la production efficace des énergies renouvelables, l’utilisation et augmentation de l’efficacité des systèmes de conversion d’énergie est devenue indispensable. Dans ce contexte, les transistors en nitrure de gallium (GaN HFETs) pour une densité de puissance commutée très importante, offrent des nouvelles possibilités et ils tirent vers le haut la gestion efficace des énergies renouvelables. Toutefois, cette nouvelle possibilité passe par un pilotage efficace des composants et une encapsulation et des interconnexions optimales. Ces travaux de thèse étudient et analyse les avantages et inconvénients d'une nouvelle structure de conversion multi cellulaire et ceux d’un driver spécifique multivoies monolithique et synchronisé pour les composants GaN, appliqué dans ce contexte précis. Ce manuscrit de thèse est composé de quatre chapitres. Après une étude bibliographique, le positionnement du convertisseur DAB (Dual Active Bridge) parmi les autres structures de conversion DC à l’aide d’une nouvelle méthodologie de comparaison (FOM topologique – Figure de Mérite) est présenté dans le premier chapitre. Afin de diminuer les contraintes de conversion d’énergie, une étude est amenée dans le chapitre 2 sur les principaux défis et enjeux d’une solution générique à travers de réalisation d’un réseau de convertisseurs. Le chapitre 3 présente la partie importante d’expérimentation et d’optimisation de la cellule élémentaire à base de convertisseurs DAB des points de vue fonctionnels mais aussi et surtout structurels. L’étude de l’isolation galvanique de la structure de conversion DAB reste l'objectif principal à développer pour démontrer le potentiel de remplacer le transformateur par une isolation capacitive. La conception de la puce de commande dédiée aux nouveaux transistors GaNs, les résultats pratiques des performances sont présentés dans le dernier chapitre. Certaines comparaisons du driver QGD (Quad Gate Driver) avec les autres solutions de transfert d’ordres de commande sont également discutées. La mise en œuvre du circuit de commande dans un convertisseur DAB afin de valider le fonctionnement de QGD est introduite dans les perspectives. / In order to improve the management and the production efficiency in renewable energy, power electronics systems have become important contributors. In this context, gallium nitride transistors (GaN HFETs) provide new opportunities for high power density, high switching speed and they pull up the effective management of renewable energies. However, this new opportunity requires effective gate drivers and optimal packaging and assembly. This thesis will introduce the general approach of a new architecture for multi cellular conversion and a monolithic multichannel and synchronized drive for GaN components, which are applicable in our specific context. This thesis is composed of four chapters. A bibliographic section is presented in first chapter. A new comparative methodology has been developed in this chapter in order to benchmark the DAB (Dual Active Bridge) converter with respect to other DC converters. In the second chapter, a generic solution (converter grid) has been explained in order to reduce the energy conversion constraints. Chapter 3 presents the important parts of the experimentation and the optimization of DAB converter. High frequency transformer replacing by capacitors is the main objective of this section. The design of the Quad Gate Driver (QGD) IC dedicated to GaNs transistors control in H bridge configuration and the results of their performances are presented in the last chapter. Some comparisons of this approach with other signal transfer solutions are also discussed. The implementation of the QGD in a full bridge transistor converter is introduced into the perspective section.
329

Conversion in Christian education and revivalism

Ozment, Robert V. January 1956 (has links)
Thesis (Ph.D.)--Boston University / PROBLEM: The problem of this dissertation is to determine the development of the views of conversion in the Christian church. This study is concerned with the two extreme schools of thought in regard to conversion which are evident in the church today. For the most part, the two trends of thinking have existed independently of each other, yet the objectives in general are the same for both. The gradual growth conversion has been associated with Christian education. The cataclysmic conversion has come to be associated with certain typee of evangelism and revivalism. This study seeks to indicate points of agreement and disagreement between the two methods of entering the Christian life and, further, to find a mediating position between the two. PROCEDURE: The major works of men who represent each era in Christian history, from the beginning of the ministry of Jesus to the present time, have been studied to determine the position the church has held, during these different intervals, concerning the method of entering the Christian life. The findings have been written in chronological order. Once the positions of either the gradual or the cataclysmic conversion have been established, the implications in favor of Christian education have been indicated. Careful analysis of the information gained from an adequate sampling of the books and articles written on the subject has made it possible to arrive at a mediating position between the two methods of conversion. [TRUNCATED]
330

A new unity power factor quasi-resonant induction heater

Sazak, Bekir Sami January 1997 (has links)
This thesis reports an investigation into the design of converters for induction heating systems based upon resonant switch mode power converter techniques. The proposed three phase unity power factor induction heating system consists of two stages of power conversions. The important requirements for each stage of the power conversion of a typical induction heating system working from a three-phase supply are identified. A wide range of power converters which fulfil these requirements are compared and evaluated. From the evaluation, the most applicable converter topologies are selected. Each selected converter class is investigated in great detail to outline their advantages and disadvantages. The first stage consists of a push-pull buck converter connected to a unity power factor rectifier stage. This stage converts the three phase AC mains supply to a required DC value. The second stage, which converters the DC into AC is a single ended resonant inverter system. Analysis of the converters has been made and the design procedure has been formulated. The design procedure allows a strenuous design of each resonant converter for particular converter applications. The final converter design has been simulated using the circuit simulation software packages Design Architect and Accusim to verify the results of analysis. The most important design and construction achievements can be summarised as follows: I A novel push-pull buck quasi-resonant converter with a three-phase rectifier stage has been built and tested. At its maximum operating frequency of 40kHz, the prototype converter delivers an output power of 500W. The converter draws nearly sinusoidal currents from the three-phase mains supply and has an input power factor approaching unity. A secondary stage resonant converter provides AC for the induction heater coil. This AC current flowing in the induction coil creates an alternating electromagnetic field for the workpiece. An induction heating coil has been designed and built by using electrical equivalent coil design method. A novel control strategy was developed to provide output power control. Both converter and inverter stage of the system are operated in the zero-current switching condition. The use of this technique allows higher switching frequencies and provides low switching losses. The full design details are presented along with simulation and practical results. The simulation and practical performance results presented show good correlation with theoretical predictions.

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