Global ETD Search

171	Développement, étude expérimentale et visualisation par holographie digitale de mini-séparateurs fluidiques (STEP-SPLITT) en vue de la séparation d'objets de taille micrométrique. / Development, experimental study and visualization by digital holography of mini fluidic separators (STEP-SPLITT) in order to separate micron-size species. Callens, Natacha N 22 December 2005 (has links) Cette thèse expérimentale s’inscrit dans le domaine des sciences séparatives et se base sur la technique de SPLITT (SPLIT-flow Thin fractionation). Son objectif consiste en l’étude des mécanismes qui sont à l’origine de la séparation, en continu et sans membrane, d’objets de taille micrométrique dans des mini-séparateurs fluidiques (Step-SPLITT). Les expériences menées, en laboratoire et lors de vols paraboliques, ont révélé le couplage complexe comme l’influence des effets hydrodynamiques et du champ gravitationnel sur la migration transverse des espèces en écoulement. Des visualisations tridimensionnelles par holographie digitale ont corroboré nos résultats et dévoilé des comportements inattendus. Les capacités séparatives des Step-SPLITT ont rendu possible l’analyse et la séparation d’objets biologiques et biomimétiques. Enfin, cette étude complétée par une modélisation tridimensionnelle de l’écoulement nous a permis de mettre au point un nouveau prototype de séparateur. This experimental thesis belongs to the field of separative sciences and is based on the SPLITT technique (SPLIT-flow Thin fractionation). The objective is to study the mechanisms that are at the origin of continuous and membraneless separation of micron-size species in mini fluidic separators (Step-SPLITT). Experiments undertaken in laboratory and during parabolic flights revealed the complex coupling of the hydrodynamic effects and the gravitational field influencing the transverse migration of the flowing species. Three-dimensional visualizations performed by digital holography confirmed our results and disclosed unexpected behaviours. The separation capacities of Step-SPLITT made the analysis and the separation of biological and biomimetic species possible. In addition this study in conjunction with a three-dimensional flow modelling enabled us to develop a new prototype of separator. Platelets FLUENT modelling Modélisation FLUENT Levure de Bière Bacillus subtilis Cellule de Hele-Shaw Vésicules phospholipidiques Yeast Hydrodynamic lift forces Globules rouges Bacillus subtilis Red blood cells Digital holographic microscopy Phospholipid vesicles Plaquettes Continuous and membraneless separation Hydrodynamic shear-induced diffusion Biological applications Hele-Shaw cell Hydrodynamic drag Applications biologiques Entraînement hydrodynamique Forces de portance hydrodynamiques Microscopie par holographie digitale Séparation en continu sans membrane
172	Développement, étude expérimentale et visualisation par holographie digitale de mini-séparateurs fluidiques (STEP-SPLITT) en vue de la séparation d'objets de taille micrométrique / Development, experimental study and visualization by digital holography of mini fluidic separators (STEP-SPLITT) in order to separate micron-size species Callens, Natacha 22 December 2005 (has links) Cette thèse expérimentale s’inscrit dans le domaine des sciences séparatives et se base sur la technique de SPLITT (SPLIT-flow Thin fractionation). Son objectif consiste en l’étude des mécanismes qui sont à l’origine de la séparation, en continu et sans membrane, d’objets de taille micrométrique dans des mini-séparateurs fluidiques (Step-SPLITT). Les expériences menées, en laboratoire et lors de vols paraboliques, ont révélé le couplage complexe comme l’influence des effets hydrodynamiques et du champ gravitationnel sur la migration transverse des espèces en écoulement. Des visualisations tridimensionnelles par holographie digitale ont corroboré nos résultats et dévoilé des comportements inattendus. Les capacités séparatives des Step-SPLITT ont rendu possible l’analyse et la séparation d’objets biologiques et biomimétiques. Enfin, cette étude complétée par une modélisation tridimensionnelle de l’écoulement nous a permis de mettre au point un nouveau prototype de séparateur.<p><p>This experimental thesis belongs to the field of separative sciences and is based on the SPLITT technique (SPLIT-flow Thin fractionation). The objective is to study the mechanisms that are at the origin of continuous and membraneless separation of micron-size species in mini fluidic separators (Step-SPLITT). Experiments undertaken in laboratory and during parabolic flights revealed the complex coupling of the hydrodynamic effects and the gravitational field influencing the transverse migration of the flowing species. Three-dimensional visualizations performed by digital holography confirmed our results and disclosed unexpected behaviours. The separation capacities of Step-SPLITT made the analysis and the separation of biological and biomimetic species possible. In addition this study in conjunction with a three-dimensional flow modelling enabled us to develop a new prototype of separator. / Doctorat en sciences appliquées / info:eu-repo/semantics/nonPublished Chimie Sciences de l'ingénieur Holography Microfluidics Shear flow Holographie Microfluidique Ecoulement cisaillé Biological applications Hydrodynamic shear-induced diffusion Continuous and membraneless separation Plaquettes Phospholipid vesicles Digital holographic microscopy Red blood cells Bacillus subtilis Globules rouges Hydrodynamic lift forces Yeast Vésicules phospholipidiques Cellule de Hele-Shaw Levure de Bière Modélisation FLUENT FLUENT modelling Platelets Hele-Shaw cell Hydrodynamic drag Applications biologiques Entraînement hydrodynamique Forces de portance hydrodynamiques Microscopie par holographie digitale Séparation en continu sans membrane
173	Systèmes de particules en interaction, approche par flot de gradient dans l'espace de Wasserstein / Interacting particles systems, Wasserstein gradient flow approach Laborde, Maxime 01 December 2016 (has links) Depuis l’article fondateur de Jordan, Kinderlehrer et Otto en 1998, il est bien connu qu’une large classe d’équations paraboliques peuvent être vues comme des flots de gradient dans l’espace de Wasserstein. Le but de cette thèse est d’étendre cette théorie à certaines équations et systèmes qui n’ont pas exactement une structure de flot de gradient. Les interactions étudiées sont de différentes natures. Le premier chapitre traite des systèmes avec des interactions non locales dans la dérive. Nous étudions ensuite des systèmes de diffusions croisées s’appliquant aux modèles de congestion pour plusieurs populations. Un autre modèle étudié est celui où le couplage se trouve dans le terme de réaction comme les systèmes proie-prédateur avec diffusion ou encore les modèles de croissance tumorale. Nous étudierons enfin des systèmes de type nouveau où l’interaction est donnée par un problème de transport multi-marges. Une grande partie de ces problèmes est illustrée de simulations numériques. / Since 1998 and the seminal work of Jordan, Kinderlehrer and Otto, it is well known that a large class of parabolic equations can be seen as gradient flows in the Wasserstein space. This thesis is devoted to extensions of this theory to equations and systems which do not have exactly a gradient flow structure. We study different kind of couplings. First, we treat the case of nonlocal interactions in the drift. Then, we study cross diffusion systems which model congestion for several species. We are also interested in reaction-diffusion systems as diffusive prey-predator systems or tumor growth models. Finally, we introduce a new class of systems where the interaction is given by a multi-marginal transport problem. In many cases, we give numerical simulations to illustrate our theorical results. Distance de Wasserstein Flots de gradient Schéma JKO Splitting Dérive non locale Diffusions non linéaires Diffusions croisées Systèmes de réaction-Diffusion Équations d'Hele-Shaw Transport optimal Transport multi-Marges Formule de Benamou-Brenier Lagrangien augmenté Mouvement de foules Espèces en interaction Wasserstein distance Gradient flows JKO scheme Splitting Nonlocal drift Nonlinear diffusions Cross-Diffusion Reaction-Diffusion systems Hele-Shaw equation Optimal transport Multi-Marginal transport Benamou-Brenier formula Augmented lagrangian Crowd motions Interacting species 519.2
174	The stock market and South Africa's economic development Frank, Ashley Gavin 30 June 2004 (has links) Financial liberalisation, through increasing investment as well as the average productivity of capital, should stimulate economic growth, or so the theory goes. Bank lending unfortunately suffers adverse selection and moral hazard effects, to which the establishment and expansion of stock markets has been offered as a remedy. However, research from developing country stock markets have shown that in many cases these markets did not complement the effects of credit market liberalisation but in rather important aspects subverted them. Countries that implemented credit market liberalisation and raised real interest rates only increased the price of debt capital rather than all capital. This caused a share price boom in many of them. When the price of equity capital fell it seriously undermined and indeed allowed large private corporations to skip altogether the main channel of high interest rates through which the theoretical McKinnon-Shaw effects were to operate. This study asks the research question of what effect the expansion of the South African stock exchange has had for its economic development. It makes use of a general empirical model to explain the relationship between financial development and real output. The model comprises indicators for growth, banking system development, stock market volatility; and, stock market development through a conglomerate index that accounts for market size, liquidity and integration with world capital markets. Quarterly data from 1989 to 2001 is analysed based on the null hypothesis that, as far as financial architecture is concerned, the development of the JSE Securities Exchange has stimulated the country's economic growth. This study found a negative and statistically significant relation between stock market development and economic growth. It suggests that while the JSE Securities Exchange is a relatively large stock market it is the presence of thin trading that prevents the proposed benefits of market development from accruing to the economy. Thus the hypothesis is rejected. However, since the only stable cointegrating vector is between growth and banking sector development, it recommends that by expanding their universal banking functions, the present banking structure, though oligopolistic, may be better suited to act as a catalyst for growth. / Business Management / D. Comm. Johansen cointegration Real interest rates Savings McKinnon-Shaw thesis De-repression Financial liberalisation Group-banking Cost of capital Granger causality Financial intermediaries Market failure Liquidity 338.968 Stock exchanges -- South Africa. Interest rates -- South Africa. Financial institutions -- South Africa Liquidity (Economics) Capital costs -- South Africa
175	Fabians and 'Fabianism' : a cultural history, 1884-1914 Downing, Phoebe C. January 2014 (has links) This thesis is a cultural history of the early Fabian Society, focusing on the decades between 1884, the Society’s inaugural year, and 1914. The canonical view is that ‘Fabianism,’ which the Oxford English Dictionary defines as the ‘doctrine and principles of the Fabian Society,’ is synonymous with State socialism and bureaucratic ‘efficiency.’ By bringing the methods of cultural history to bear on the Society’s founding members and decades, this thesis reveals that ‘Fabianism’ was in fact used as a dynamic metonymy, not a fixed doctrine, which signified a range of cultural, and even literary, meanings for British commentators in the 1890s and 1900s (Part 1). Further, by expanding the scope of traditional histories of the Fabian Society, which conventionally operate within political and economic sub-fields and focus on the Society’s ‘official’ literature, to include a close examination of the broader discursive context in which ‘Fabianism’ came into being, this thesis sets out to recover the symbolic aspects of the Fabians’ efforts to negotiate what ‘Fabianism’ meant to the English reading public. The Fabians’ conspicuous leadership in the modern education debates and the liberal fight for a ‘free stage,’ and their solidarity with the international political émigrés living in London at the turn of the twentieth century all contribute to this revised perspective on who the founding Fabians were, what they saw themselves as trying to achieve, and where the Fabian Society belonged—and was perceived to belong—in relation to British politics, culture, and society (Part 2). The original contribution of this thesis is the argument that the Fabians explicitly and implicitly evoked Matthew Arnold as a precursor in their efforts to articulate a kind of Fabian—latterly social-democratic—liberalism and a public vocation that balanced English liberties and the duty of the State to provide the ‘best’ for its citizens in education and in culture, as in politics. 361.6
176	Instabilités hydrodynamiques des liquides magnétiques miscibles et non miscibles dans une cellule de Hele-Shaw Igonin, Maksim 29 November 2004 (has links) (PDF) Ce manuscrit décrit analytiquement et numériquement les instabilités d'un fluide magnétique dans une cellule de Hele-Shaw. On considère l'interface entre un fluide magnétique et un autre fluide non magnétique, miscible ou non, soumise à un champ magnétique homogène normal à la cellule ou à l'interface. Le champ démagnétisant est inhomogène à cette interface et génère un mouvement convectif des fluides. Dans la première partie, nous avons utilisé une analyse linéaire de stabilité entre deux liquides miscibles pour une distribution donnée de concentration à l'interface. Les résultats s'appliquent aussi à la stabilité d'un réseau de concentration induit par une expérience de Rayleigh forcé. Nous avons démontré que l'équation de Brinkman décrit mieux la dissipation visqueuse dans une cellule de Hele-Shaw que celle de Darcy. Nous avons trouvé que la viscosité (et non la diffusion massique) donnait à l'écoulement une échelle de longueur de l'ordre de l'épaisseur de la cellule dans le cas des forçages élevés. Dans la seconde partie de notre étude, nous avons modélisé la dynamique non linéaire de l'interface avec une tension superficielle par la méthode des intégrales de frontière. Nous avons décrit la modification des doigts de Saffman–Taylor par les forces magnétostatiques. Nous avons obtenu des structures dendritiques proches de celles observées expérimentalement et analysé quelques aspects de la formation des motifs. [PHYS:COND] Physics/Condensed Matter [PHYS:MPHY] Physics/Mathematical Physics liquide magnétique cellule de Hele-Shaw loi de Darcy analyse de stabilité stabilité hydrodynamique modes normaux spectre continu mélange interfaces miscibles convection–diffusion microfluidics digitation visqueuse instabilité de Saffman–Taylor instabilité de Rayleigh–Taylor dendrite formation des motifs équations intégrales de frontière champ démagnétisant force de Kelvin
177	The stock market and South Africa's economic development Frank, Ashley Gavin 30 June 2004 (has links) Financial liberalisation, through increasing investment as well as the average productivity of capital, should stimulate economic growth, or so the theory goes. Bank lending unfortunately suffers adverse selection and moral hazard effects, to which the establishment and expansion of stock markets has been offered as a remedy. However, research from developing country stock markets have shown that in many cases these markets did not complement the effects of credit market liberalisation but in rather important aspects subverted them. Countries that implemented credit market liberalisation and raised real interest rates only increased the price of debt capital rather than all capital. This caused a share price boom in many of them. When the price of equity capital fell it seriously undermined and indeed allowed large private corporations to skip altogether the main channel of high interest rates through which the theoretical McKinnon-Shaw effects were to operate. This study asks the research question of what effect the expansion of the South African stock exchange has had for its economic development. It makes use of a general empirical model to explain the relationship between financial development and real output. The model comprises indicators for growth, banking system development, stock market volatility; and, stock market development through a conglomerate index that accounts for market size, liquidity and integration with world capital markets. Quarterly data from 1989 to 2001 is analysed based on the null hypothesis that, as far as financial architecture is concerned, the development of the JSE Securities Exchange has stimulated the country's economic growth. This study found a negative and statistically significant relation between stock market development and economic growth. It suggests that while the JSE Securities Exchange is a relatively large stock market it is the presence of thin trading that prevents the proposed benefits of market development from accruing to the economy. Thus the hypothesis is rejected. However, since the only stable cointegrating vector is between growth and banking sector development, it recommends that by expanding their universal banking functions, the present banking structure, though oligopolistic, may be better suited to act as a catalyst for growth. / Business Management / D. Comm. Johansen cointegration Real interest rates Savings McKinnon-Shaw thesis De-repression Financial liberalisation Group-banking Cost of capital Granger causality Financial intermediaries Market failure Liquidity 338.968 Stock exchanges -- South Africa. Interest rates -- South Africa. Financial institutions -- South Africa Liquidity (Economics) Capital costs -- South Africa
178	The life and times of Kama Chungwa, 1798-1875 Yekela, Drusilla Siziwe January 1989 (has links) Few students of History understand the derivation and/or origin of the Gqunukhwebe oath "Ndifung' uChungw' efel' ennyameni: I swear by Chungwa who is lying dead at Mnyameni (Alexandria)." A desire to eludicate this point and other related facts inspired me to undertake a close examination of the history of the Gqunukhwebe people, selecting as my main theme the life-work of Chief Kama. In the first chapter I am discussing the creation of the Gqunukhwebe Chiefdom under Khwane by the Xhosa King, Tshiwo. The central theme here is the Black-White confrontation of the 17th - 18th centuries on the Cape Eastern Frontier. As a result of the collision the Gqunukhwebe people were forced to make a home on the banks of the Thwecu River along the east coast. It was here that Kama reached early manhood. The second chapter describes the establishment of Wesleyville Missionary Station by William Shaw in 1823, the first Methodist Missionary Institution in all Xhosaland. In chapter three the discussion centers on the significance of Kama's conversion. An unforeseen outcome of his public profession of the Christian faith was that it not only stigmatized the latter religion as a force destructive of the old order in Xhosa society, but it also reshaped Kama's political image for the good of his religious life. He not only fled from the neighbourhood of his relations and sojourned in a strange land, but also reinforced the Colonial forces in the contemporary frontier struggles. His integrity, self-sacrifice and pro-Colonial inclination eventually won him Middledrift. Chapter four opens with Kama's settling in Middledrift. The theme here is two-pronged. It presents the 'Cattle-Killing' delusion as a source of new trials for the 'priest-chief', and at the same time exposes the Colonial Government's efforts to gain ascendancy above the Xhosa chiefs. Kama's land was the first testing ground in this respect, and the Chief was initially agreeable to the scheme. Chapter five alludes to instances of Chief Kama's unco-operative attitude as signs that his compromising spirit had its limits. An atmosphere of disregard towards Kama pervades the period. But the adversities that threatened to dominate his later life did not by any means shake his Christian principles and convictions. The traces of his good works may to this day be seen in Middledrift, the traditional home of the Kamas. Kama, William, 1798-1875 Shaw, William, 1798-1872 Gqunukhwebe (African people) -- History Wesleyville mission Converts -- South Africa
179	Prophetisches Reden und Evangelisation: eine missiologische Untersuchung der über Berlin ausgesprochenen Prophetien (1980-2000) / Prophecy and evangelisation : a missiological study of prophecies regarding Berlin (1980-2000) Heim, Detlef Peter 31 October 2002 (has links) Text in German / Prophetie und Evangelisation sind zentrale Themen der Bibel und wichtige Instrumente Gottes. Biblische Berichte zeigen, dass Mission und Evangelisation oft erst durch ein prophetisches Wort moglich wurde. Das erste Kapitel widmet sich diesen Themen. Es ist das Anliegen dieser Studie, die in den Jahren 1980-2000 uber Berlin ausgesprochenen Prophetien zu analysieren. Die Prophetien werden mit biblischen Aussagen verglichen, gegeneinander ins Verhaltnis gesetzt und auf ihre missionstheoiogische Relevanz hin untersucht. Eine Befragung einiger Berliner Leber chainsmatisch-gepragter Gemeinden liefert den praktischen Anteil dieser Studie. Die theoretischen Grundlagen werden im zweiten und die Ergebnisse im dritten Kapitel behandelt. Es ist zu betonen, dass sich die untersuchten Prophetien jeglicher objektiver Beurteilung entziehen. Alle Angaben sind zeitlich nicht gebunden und sehr allgemein gehalten. Allen gemeinsam ist jedoch ein geistlicher Quantensprang, der von einer flachendeckenden Ausgiessung des Geistes Gottes uber Berlin handelt. Dieser Sachverhalt wird im vierten Kapitel dargestellt und diskutiert. / Prophecy and evangelisation are central topics of the Bible and instruments of God, Biblical reports show, that mission and evangelisation were mostly possible by a prophetic word (Chapter one). The concern of this study is to analyse the prophecies spoken out for Berlin between the years 1980 to 2000. The prophecies were compared with biblical statements, were proportionate to one another and were analysed regarding their mission-theologicai relevance. A questioning of few leaders of charismatic-embossed churches of Berlin gives the practical part of the study (the theoretical part see chapter two, the results see chapter three). It has to be articulated, that there is no objective judgement for the analysed prophecies. All indications are not bound by time and were given in general sense. All prophecies deal with a spiritual quantum leap, who speaks of an out-pouring of the Spirit of God over Berlin covering the whole area (Chapter four). / Christian Spirituality, Church History and Missiology / M.Th. (Missiology) Prophetie Evangelisation Charismatische Theologie Bibel und Prophetie Bibel und Evangelisation Berlin Berlinprophetien Gwen Shaw Mike Bickle Pat Cocking Julie Baxter Kriterienkatalog Prophetieanalyse Prophetieverlauf Prophetiebewertung Charismatische Gemeinden Berlins Befragung Prophecy Evangelisation Charismatic theology Bible and prophecy Bible and evangelisation Berlin Prophecies for Berlin Catalogue of criteria Analysis of prophecies Analysis of prophecies Process of prophecies Evaluation of prophecies Charismatic churches of Berlin Questioning 270.820943155 Evangelistic work -- Germany -- History Prophecy -- Christianity Pentecostalism -- Germany
180	Prophetisches Reden und Evangelisation : Eine missiologische Untersuchung der uber Berlin ausgesprochenen Prophetien (1980-2000) / Prophecy and evangelisation : A missiological study of prophecies regarding Berlin (1980-2000) Heim, Detlef Peter 11 1900 (has links) Prophetie und Evangelisation sind zentrale Themen der Bibel und wichtige Instrumente Gottes. Bib'lische Berichte zeigen, dass Mission und Evangelisation oft erst durch ein prophetisches Wort miiglich wurde. Das erste Kapitel widmet sich diesen Themen. Es ist das Anliegen dieser Studie, die in den Jahren 1980-2000 iiber Berlin ausgesprochenen Prophetien zu analysieren. Die Prophetien werden mit biblischen Aussagen verglichen, gegeneinander ins Verhliltnis gesetzt und auf ihre missionstheologische Relevanz hin untersucht. Eine Befragung einiger Berliner Leiter charismatisch-geprligter Gemeinden liefert den praktischen Anteil dieser Studie. Die theoretischen Grundlagen werden im zweiten und die Ergebnisse im dritten Kapitel behandelt. Es ist zu betonen, <lass sich die untersuchten Prophetien jeglicher objektiver Beurteilung entziehen. Aile Angaben sind zeitlich nicht gebunden und sehr allgemein gehalten. Allen gemeinsam ist jedoch ein geistlicher Quantensprung, der von einer flachendeckenden AusgieBung des Geistes Gottes iiber Berlin handelt. Dieser Sachverhalt wird im vierten Kapitel dargestellt und diskutiert. / Prophecy and evangelisation are central topics of the Bible and instruments of God. Biblical reports show, that mission and evangelisation were mostly possible by a prophetic word (Chapter one). The concern of this study is to analyse the prophecies spoken out for Berlin between the years 1980 to 2000. The prophecies were compared with biblical statements, were proportionate to one another and were analysed regarding their mission-theological relevance. A questioning of few leaders of charismatic-embossed churches of Berlin gives the practical part of the study (the theoretical part see chapter two, the results see chapter three). It has to be articulated, that there is no objective judgement for the analysed prophecies. All indications are not bound by time and were given in general sense. All prophecies deal with a spiritual quantum leap, who speaks of an out-pouring of the Spirit of God over Berlin covering the whole area (Chapter four). / Text in German / Titles in German and English / Keywords in German and English / M. Th. (Missiology) Prophecy Evangelisation Charismatic theology Bible and prophecy Bible and evangelisation Berlin Prophecies for Berlin Gwen Shaw Mike Bickle Pat Cocking Julie Baxter Catalogue of criteria Analysis of prophesies Process of prophecies Evaluation of prophecies Charismatic churches of Berlin Questioning Prophetie Charismatische Theologie Bibel und Prophetie Bibel und Evangelisation Berlinprophetien Kriterienkatalog Prophetieanalyse Prophetieverlauf Prophetiebewertung Charismatische Gemeinden Berlins Befragung 270.820943155 Evangelistic work -- Germany -- History Prophecy -- Christianity Pentecostalism -- Germany

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