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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.
41

Plug-in Hybrid Electric Vehicle Supervisory Control Strategy Considerations for Engine Exhaust Emissions and Fuel Use

Walsh, Patrick McKay 01 June 2011 (has links)
Defining key parameters for a charge sustaining supervisory (torque split) control strategy as well as an engine and catalyst warm-up strategy for a Split Parallel Architecture Extended-Range Electric Vehicle (SPA E-REV) is accomplished through empirically and experimentally measuring vehicle tailpipe emissions and energy consumption for two distinct control strategies. The results of the experimental testing and analysis define how the vehicle reduces fuel consumption, petroleum energy use and greenhouse gas emissions while maintaining low tailpipe emissions. For a SPA E-REV operating in charge sustaining mode with the engine providing net propulsive energy, simply operating the engine in regions of highest efficiency does not equate to the most efficient operation of the vehicle as a system and can have adverse effects on tailpipe emissions. Engine and catalyst warm-up during the transition from all-electric charge depleting to engine-dominant charge sustaining modes is experimentally analyzed to evaluate tailpipe emissions. The results presented are meant to define key parameters for a high-level torque-split strategy and to provide an understanding of the tradeoffs between low energy consumption and low tailpipe emissions. The literature review gives a background of hybrid and plug-in hybrid vehicle control publications including tailpipe emissions studies, but does not include experimental results and comparisons of supervisory strategies designed for low fuel consumption and low tailpipe emissions the SPA E-REV architecture. This paper details the high-level control strategy chosen for balancing low energy consumption and low tailpipe emissions while the engine is operating. Vehicle testing data from a chassis dynamometer is presented in support of the research. / Master of Science
42

Tiyo Soga : man of four names

Davis, Joanne Ruth 02 1900 (has links)
This study finds its place in a global resurgence of interest in the Reverend Tiyo 'Zisani' Soga's and nineteenth century black political activism. It attempts to deepen our inderstanding od Soga's global milieu and identity, providing an assessment of scholarship on Soga's life and commenting on the major critical works on Soga provided by Williams, de Kock and Attwell and addressing the question of his multiple identities. The thesis explores Soga's relationship with textuality to reveal the struggles he encountered during his career as an author, most especially as the translator of the Bible. / English Studies / D. Litt. et Phil.
43

Tiyo Soga : man of four names

Davis, Joanne Ruth 02 1900 (has links)
This study finds its place in a global resurgence of interest in the Reverend Tiyo 'Zisani' Soga's and nineteenth century black political activism. It attempts to deepen our inderstanding od Soga's global milieu and identity, providing an assessment of scholarship on Soga's life and commenting on the major critical works on Soga provided by Williams, de Kock and Attwell and addressing the question of his multiple identities. The thesis explores Soga's relationship with textuality to reveal the struggles he encountered during his career as an author, most especially as the translator of the Bible. / English Studies / D. Litt. et Phil.
44

A Mass Spectrometry Approach to Ligand Identification for Orphan Fly and Human Nuclear Receptors

Pardee, Keith Ian 01 September 2010 (has links)
The nuclear receptor superfamily is responsible for regulating the expression of genes involved in development, reproduction and metabolism. These transcription factors control the expression of their target genes through the binding of small molecule regulators to their ligand binding domains. Classical nuclear receptors include the steroid receptors, which bind endocrine hormones and have been important targets of pharmaceutical intervention. However, approximately one half of the human nuclear receptors remain orphans and are without known cognate ligands. Focusing on the Drosophila orthologues of these orphan receptors, this project used mass spectrometry to identify the chemical diversity associated with the receptors following expression in recombinant systems. In a genome-wide screen of Drosophila nuclear receptors, this approach identified co-purifying molecules with a number of receptors. The physiological relevance of these putative ligand/receptor pairs was determined through biochemical analysis, in vivo characterization and structure determination. Ligand(s) or the ligand state was identified for the Drosophila receptors: DHR3, DHR96, E75, Ftz-f1 and USP. Of these, three were validated through the efforts of this project, and independent groups confirmed the remaining two. The most significant findings were the discoveries that the fly nuclear receptor E75 is regulated by heme, gas and redox, and that there is a similar regulatory scheme in the human orthologues, Reverbα and β. Furthermore, crystallization of the heme-bound Rev-erbβ ligand binding domain was also achieved, and this provided key insights into the mechanism of ligand regulation for the Rev-erbs. This project highlighted the role of nuclear receptors in metabolic surveillance. The ligands/signals identified in association with these receptors include: cholesterol, dehydrocholesterol, heme, NO, CO, redox and phospholipids. Unlike the classical steroid hormones, these are not dedicated signaling molecules, but instead are key substrates or products of metabolism. In the context of nuclear receptor signaling, I hypothesize that these metabolites serve as metabolic indicators/signals in the regulation of development and metabolism. Furthermore, four of these Drosophila receptors comprise the ecdysone-response pathway in the developing fly. Taken together, this suggests that both the metabolic state of the organism and steroid hormones drive nuclear receptor regulation of development.
45

Banquet festif et banquet macabre : analyse narrative et structurelle d’Ap 19

Côté, Richard 07 1900 (has links)
À cause de son langage symbolique et de l’absence d’une trame narrative bien dessinée, l’Apocalypse de Jean constitue un gros défi pour l’exégèse, d’autant plus que ce livre réutilise un important matériel vétérotestamentaire mais sans jamais faire de citations explicites. La présente recherche se propose de traiter le chapitre 19 comme une unité littéraire significative à l’intérieur de ce livre complexe, même s’il ne montre ni un récit suivi ni une parfaite cohérence sur le plan narratif, présentant même des discordances avec d’autres parties du livre. Par contre, sur le plan théologique, un discours cohérent et significatif s’en dégage lorsqu’on joint à l’analyse narrative une analyse structurelle. La combinaison de ces deux méthodes synchroniques permet d’exposer des parallélismes frappants et de décrire une intrigue qui traite de l’accomplissement inéluctable de la justice divine, symbolisée par le contraste entre deux grands banquets, l’un festif et l’autre macabre. Enfin, cette recherche préserve le caractère évocateur des symboles et préconise une lecture ironique pour certains passages. / Due to its constant use of symbolism within a loose narrative framework, John’s Revelation poses a formidable exegetic challenge. Moreover, this book reuses a large amount of Old Testament material while never quoting from the OT. This M.A. thesis posits that Rev 19 is a significant literary unit encased in the larger context of the complex Book of Revelation, although its narrative frame is not closely argued, even displaying some contradictions with other parts of the book. However, on a theological level, a coherent, consistent message can be unveiled, when adding a structural analysis to the narrative analysis. The combination of these two synchronic approaches highlights some striking parallels and describes a plot that talks about the certain achievement of God’s justice, symbolized by the contrast of two feasts, one joyous and the other gruesome. Finally, this research leaves intact the evocative nature of the symbols and advocates an ironic reading of some passages.
46

Scale and Stress Effects on Hydro-Mechanical Properties of Fractured Rock Masses

Baghbanan, Alireza January 2008 (has links)
In this thesis, the effects of size and stress on permeability, deformability and strength of fractured rock masses are investigated. A comparison study was carried out to examine the effects of considering, or not considering, the correlation between distributions of fracture apertures and fracture trace lengths on the hydro-mechanical behavior of fractured rocks. The basic concepts used are the fundamental principles of the general theory of elasticity, Representative Elementary Volume (REV), the tensor of equivalent permeability, and the strength criteria of the fractured rocks. Due to the size and stress dependence of the hydro-mechanical properties of rock fractures, the overall effective (or equivalent) hydro-mechanical properties of the fractured rocks are also size and stress-dependent. However, such dependence cannot be readily investigated in laboratory using small samples, and so numerical modeling becomes a necessary tool for estimating their impacts. In this study, a closed-form relation is established for representing the correlation between a truncated lognormal distribution of fracture apertures and a truncated power law distribution of trace lengths, as obtained from field mapping. Furthermore, a new nonlinear algorithm is developed for predicting the relationship between normal stress and normal displacement of fractures, based on the Bandis model and the correlation between aperture and length. A large number of stochastic Discrete Fracture Network (DFN) models of varying sizes were extracted from some generated large-sized parent realizations based on a realistic fracture system description from a site investigation programme at Sellafield, UK, for calculating the REV of hydro-mechanical properties of fractured rocks. Rotated DFN models were also generated and used for evaluation of the distributions of directional permeabilities, such that tensors of equivalent permeability could be established based on stochastically established REVs. The stress-dependence of the permeability and the stress-displacement behaviour were then investigated using models of REV sizes. The Discrete Element Method (DEM) was used for numerical simulation of the fluid flow, deformability properties and mechanical strength behavior of fractured rocks. The results show significant scale-dependency of rock permeability, deformability and strength, and its variation when the correlation between aperture and trace length of fractures are concerned, with the overall permeability and deformability more controlled by dominating fractures with larger apertures and higher transmissivity and deformability, compared with fracture network models having uniform aperture. As the second moment of aperture distribution increases, a fractured rock mass shows more discrete behavior and an REV is established in smaller value of second moment with much larger model size, compared with the models with uniform fracture aperture. When the fracture aperture pattern is more scattered, the overall permeability, Young’s modulus and mechanical strength change significantly. The effect of stress on permeability and fluid flow patterns in fractured rock is significant and can lead to the existence or non-existence of a permeability tensor. Stress changes the fluid flow patterns and can cause significant channeling and the permeability tensor, and REV may be destroyed or re-established at different applied stress conditions. With an increase in the confining stress on the DEM models, the strength is increased. Compared with the Hoek-Brown criterion, the Mohr-Coulomb strength envelope provides a better fit to the results of numerical biaxial compression tests, with significant changes of the strength characteristic parameters occurring when the second moment of the aperture distribution is increased. / QC 20100702
47

Régulation de l'activité de la protéine Rev du HIV-1 par des modifications post-traductionnelles et inhibition de sa fonction par des peptides actifs à partir du milieu extracellulaire

Vitte, Anne-Laure 11 December 2006 (has links) (PDF)
La protéine Rev du HIV-1 joue un rôle essentiel dans le cycle viral en permettant l'export vers le cytoplasme des ARNm viraux non ou partiellement épissés. Dans la perspective d'inhiber cette fonction, nous avons mis au point des peptides capables de reconnaître Rev et d'inhiber sa fonction, appelés SHPR (Sumo Heptapeptide Protein transduction domain for binding Rev). Nous avons établi que ces peptides sont capables de diffuser à travers les membranes plasmiques pour atteindre ensuite le noyau, où ils induisent la dégradation de la protéine virale, principalement par la voie du protéasome. Des expériences de mutagenèse ont précisé la contribution des différents domaines des SHPR dans l'action antivirale, et ont démontré que peu d'améliorations sont possibles pour optimiser leurs propriétés. Enfin, nous avons montré que Rev n'est pas régulée par sumoylation mais qu'elle peut être modifiée par addition d'une chaîne de polyubiquitine, qui stabilise la protéine mais module son activité
48

Banquet festif et banquet macabre : analyse narrative et structurelle d’Ap 19

Côté, Richard 07 1900 (has links)
À cause de son langage symbolique et de l’absence d’une trame narrative bien dessinée, l’Apocalypse de Jean constitue un gros défi pour l’exégèse, d’autant plus que ce livre réutilise un important matériel vétérotestamentaire mais sans jamais faire de citations explicites. La présente recherche se propose de traiter le chapitre 19 comme une unité littéraire significative à l’intérieur de ce livre complexe, même s’il ne montre ni un récit suivi ni une parfaite cohérence sur le plan narratif, présentant même des discordances avec d’autres parties du livre. Par contre, sur le plan théologique, un discours cohérent et significatif s’en dégage lorsqu’on joint à l’analyse narrative une analyse structurelle. La combinaison de ces deux méthodes synchroniques permet d’exposer des parallélismes frappants et de décrire une intrigue qui traite de l’accomplissement inéluctable de la justice divine, symbolisée par le contraste entre deux grands banquets, l’un festif et l’autre macabre. Enfin, cette recherche préserve le caractère évocateur des symboles et préconise une lecture ironique pour certains passages. / Due to its constant use of symbolism within a loose narrative framework, John’s Revelation poses a formidable exegetic challenge. Moreover, this book reuses a large amount of Old Testament material while never quoting from the OT. This M.A. thesis posits that Rev 19 is a significant literary unit encased in the larger context of the complex Book of Revelation, although its narrative frame is not closely argued, even displaying some contradictions with other parts of the book. However, on a theological level, a coherent, consistent message can be unveiled, when adding a structural analysis to the narrative analysis. The combination of these two synchronic approaches highlights some striking parallels and describes a plot that talks about the certain achievement of God’s justice, symbolized by the contrast of two feasts, one joyous and the other gruesome. Finally, this research leaves intact the evocative nature of the symbols and advocates an ironic reading of some passages.
49

Samrådsunderlag för Lysekilsprojektet : Forskning och utveckling av vågkraft

Ström, Simon January 2014 (has links)
The aim of this research is to find out what environmental impact a wave power park has on the Swedish west coast by creating a consultation paper (”Samrådsunderlag”) for the Lysekilproject at Uppsala University. To highlight the complexity of the problem a system analytic approach was used and illustrated by a Causal Loop Diagram. The overall assessment of the Lysekilprojects wave power park at the Swedish west coast is that it will have a low impact on the environment. This is due to the relative small size of the wave power park and some technical solutions made with the environmental aspect in mind. Artificial reefs and a sanctuary for marine species are effects created by the wave power park and in the longer term the impact will give access to an untapped source of renewable energy, wave energy. Thus reducing the need of fossil fuels and making it possible to reach the Swedish national environmental goals. / Lysekilsprojektet
50

Strength and deformability of fractured rocks

Noorian-Bidgoli, Majid January 2014 (has links)
This thesis presents a systematic numerical modeling framework to simulate the stress-deformation and coupled stress-deformation-flow processes by performing uniaxial and biaxial compressive tests on fractured rock models with considering the effects of different loading conditions, different loading directions (anisotropy), and coupled hydro-mechanical processes for evaluating strength and deformability behavior of fractured rocks. By using code UDEC of discrete element method (DEM), a series of numerical experiments were conducted on discrete fracture network models (DFN) at an established representative elementary volume (REV), based on realistic geometrical and mechanical data of fracture systems from field mapping at Sellafield, UK. The results were used to estimate the equivalent Young’s modulus and Poisson’s ratio and to fit the Mohr-Coulomb and Hoek-Brown failure criteria, represented by equivalent material properties defining these two criteria. The results demonstrate that strength and deformation parameters of fractured rocks are dependent on confining pressures, loading directions, water pressure, and mechanical and hydraulic boundary conditions. Fractured rocks behave nonlinearly, represented by their elasto-plastic behavior with a strain hardening trend. Fluid flow analysis in fractured rocks under hydro-mechanical loading conditions show an important impact of water pressure on the strength and deformability parameters of fractured rocks, due to the effective stress phenomenon, but the values of stress and strength reduction may or may not equal to the magnitude of water pressure, due to the influence of fracture system complexity. Stochastic analysis indicates that the strength and deformation properties of fractured rocks have ranges of values instead of fixed values, hence such analyses should be considered especially in cases where there is significant scatter in the rock and fracture parameters. These scientific achievements can improve our understanding of fractured rocks’ hydro-mechanical behavior and are useful for the design of large-scale in-situ experiments with large volumes of fractured rocks, considering coupled stress-deformation-flow processes in engineering practice. / <p>QC 20141111</p>

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