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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.
21

“Dead. He is Dead. God blesses America” : Den Amerikanska pressens gestaltning av kriget mot terrorism kring Usama bin Ladins död / “Dead. He is Dead. God blesses America” : Framing of the War on Terror in the American press surrounding the death of Osama bin Laden

Adrian, Carl, Holm, Jonas January 2013 (has links)
Almost 10 years after the attack on World Trade Center Sept. 11 2001, Osama bin Laden was shot and killed on May 2 2011 in Pakistan. How was this event framed by the media with regards to the global war on terror? This study compares two different American newspapers – the New York Times and the New York Daily News – and how they framed the war on terrorism in the Middle East from May 2 to May 15 2011. By analyzing the framing in a perspective of the four functions of framing theory: define problems, diagnose causes, make moral judgments and suggest remedies, we found considerable differences in each papers frames. Through a qualitative text analysis of the opinion pages in these two newspapers, using three themes as a base, we found a number of differences. While the New York Times contained a form of open discussion about problems and remedies, New York Daily News takes an emotional and moral approach. These differences in content may affect the opinions of the readers. We speculate that the more open and suggestive nature of the New York Times, also opens the minds of the readers enabling them to form opinions in a liberated sense. Thus the more closed, emotional and moral nature of the New York Daily News may have greater impact on an individual’s ability to form its own opinions and moral values.
22

Varieties of Fundamentalism

De Sousa, Rebecca M. 04 January 2007 (has links)
The term “Fundamentalism” used as a comparative category within the academic study of religion has become problematic. Fundamentalism, is not one comprehensive movement but is, in fact, a phenomenon which encompasses a variety of beliefs, practices, and expectations. This thesis will explore the diversity of several different and distinct fundamentalist movements. I will discuss the natures of four Christian movements that have been labeled “fundamentalist” – Jehovah’s Witnesses, Christian Reconstructionists, Jerry Falwell and Pat Robertson – on several key points, eschatology, political philosophy, as well as level of social involvement. I will then turn to fundamentalism as it is used as a category to describe a global phenomenon. I will discuss three different scholarly approaches by turning to the work of Bruce Lawrence, Mark Juergensmeyer, and Bruce Lincoln on the Islamic “fundamentalist” group al- Qaeda. Finally I will argue that the category “fundamentalism” can be best understood in terms of a family resemblance.
23

National identity and nationalism in the speeches of Osama Bin Laden

Harris, Kimberly M. January 2007 (has links)
Thesis (M.A.)--University of Missouri-Columbia, 2007. / The entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file. Title from title screen of research.pdf file (viewed on November 12, 2007) Includes bibliographical references.
24

Simulation des écoulements turbulents avec des particules de taille finie en régime dense / Numerical simulation of particle laden turbulent flows with finite-sized particles in dense regime

Brändle de Motta, Jorge César 27 June 2013 (has links)
Un grand nombre d'écoulements naturels et industriels mettent en jeu des particules (sédimentation,lit fluidisé, sprays...). Les écoulements chargés en particules sont bien décrits numériquement sous l'hypothèse des particules plus petites que toutes les échelles de l'écoulement. Cette thèse consiste à simuler numériquement une turbulence homogène et isotrope soutenue chargée en particules dont la taille est supérieure à l'échelle de Kolmogorov. Pour se faire une méthode de simulation a été développée au sein du code Thétis puis validée. L'originalité de cette méthode consiste en l'utilisation d'une approche de pénalisation associée à la viscosité dans la zone solide. Les particules sont transportées de façon lagrangienne. Les principaux résultats concernent trois simulations faisant varier le rapport de densité entre le fluide et le solide. Chaque simulation simule le mouvement de 512particules avec un diamètre 22 fois plus grand que l'échelle spatiale de Kolmogorov remplissant ainsi3% du volume total. La dispersion des particules est étudiée et montre des comportements comparables à ceux observés pour des particules ponctuelles. Un intérêt particulier est porté sur le régime collisionnel. On observe que la corrélation des vitesses avec le fluide environnant réduit le nombre de chocs frontaux par rapport au cas théorique de particules d'un gaz dense. L'effet de la prise en compte du fluide visqueux entre les particules (couche de lubrification) lors de la collision a été étudiée. L'écoulement moyen à l'échelle des particules est aussi analysé, mettant en évidence l'existence d'une couche de dissipation autour des particules. / Many applications and natural environment flows make use of particles (sedimentation, fluidized bed,sprays...). Particle laden flows are described correctly by numerical methods when the particles are smaller than all other spatial scales of the flow. This thesis involves the numerical simulation of a particle laden sustained homogeneous isotropic turbulence whose particle's size is larger than the Kolmogovov spatial scale. A numerical method has been developed and validated in the numerical code Thetis. The novelty of this method is the viscosity penalization approach. The particles are tracked by a Lagrangian way. The main results obtained are related to three simulations where the density ratio between the solid and the fluid varies. Each simulation reproduces the movement of 512particles whose diameter is 22 times the Kolmogorov spatial scale (3% volumetric solid fraction).The dispersion of particles is studied and has similar behavior than those observed with point particles simulations. The collision regime is also investigated. It is shown that he number of frontal collision is lower than its estimate for kinetic theory of gazes because there is a correlation between the particles velocity and the surrounding fluid. The modification of the collision regime when the lubrication film between particles at collision is taken into account is studied. Finally, the averaged flow around particles is analyzed and shows that there is a dissipation layer around particles.
25

Membranes plissées à la surface de l'eau : des films élastiques aux radeaux granulaires / Folds in floating membranes : from elastic sheets to granular rafts

Jambon-Puillet, Etienne 03 October 2016 (has links)
Cette thèse porte sur le flambement d'une interface chargée en particules: une monocouche de grains denses et athermaux à une interface liquide-fluide plane que l'on appelle radeau granulaire. Ces radeaux se rident et se plient lorsqu'ils sont compressés comme des films élastiques. Nous étudions cette instabilité de flambement expérimentalement et théoriquement dans ces deux systèmes dans le cadre de la mécanique des milieux continus. Nous commençons par examiner les plis dans des films élastiques denses. Nous soulignons l'influence du poids du film dans la formation du pli. Puis nous explorons le régime des très grandes déformations, après que le film soit entré en contact avec lui-même. Suivant la densité du film, le pli se replie vers l'interface ou s'enfonce vers le fond de la cuve. Ensuite nous étudions les rides et les plis dans les radeaux granulaires compressés uniaxialement. A mesure que la compression augmente, nous observons deux motifs de ride distincts, puis la déformation se localise en un unique pli. Nous prédisons la forme et la taille des plis avec un modèle élastique résolu numériquement. Nous insistons sur les limitations de ce modèle et montrons que le caractère granulaire de ces radeaux n'est pas toujours négligeable. Enfin, nous déposons des gouttes d'eau à la surface des radeaux. Lorsque les particules sont hydrophobes et suffisamment grandes, elles capturent un film d'huile qui sépare la goutte du bain et empêche la coalescence. Puis nous modifions la taille de ces gouttes qui prennent des formes inhabituelles. Ces gouttes peuvent ensuite être encapsulées dans une fine couche de particules et d'huile conduisant à des gouttes d'eau dans l'eau. / This thesis is concerned with the buckling of a model particle laden interface: a monolayer of dense, athermal particles at a planar liquid-fluid interface that we call a granular raft. Under compression granular rafts wrinkle and fold like elastic sheets. We investigate this buckling instability experimentally and theoretically for these two systems under the continuum mechanics framework. We first look at folds in custom made dense floating elastic sheets. We highlight the influence of the sheet's own weight in the fold formation and shape. Then we explore the regime of very large deformations, after the sheet contacts itself. Depending on the sheet density, the fold in self-contact either bends back toward the interface or sinks down toward the bottom of the tank. We then look at wrinkles and folds in granular rafts. Our experimental apparatus allows us to compress the rafts uniaxially and extract their morphology. As compression increases, we observe two distinct wrinkling patterns, then the deformations localise in a unique fold. We develop an elastic model that we solve numerically to predict the fold shape and size. We then highlight the limitations of the model and show that the granular nature of these rafts cannot always be neglected. Finally, we deposit water droplets on top of granular rafts. If the particles are hydrophobic and large enough, the raft can inhibit coalescence indefinitely via particle bridging. When we vary the size of these floating drops, they take unusual shapes which depend on the raft properties. These drops can then be encapsulated in a thin composite oil-particle layer leading to water droplets in water.
26

Auslegung eines induktiven Energieübertragungssystems für Lastenpedelecs

Vogt, Johannes Paul, Kertzscher, Jana 22 September 2021 (has links)
Der vorliegende Beitrag beschreibt die Auslegung eines Resonanzübertragers für den Einsatz in kontaktlosen Pedelec-Ladesystemen. Dazu wird im ersten Teil die Schrittfolge des Auslegungsprozesses erarbeitet sowie die notwendigen Systemanforderungen analysiert. Der zweite Teil beschreibt die simulationsgestützte Bestimmung der Systemparameter. / This paper describes the design of a resonant transformer for use in contactless pedelec charging systems. In the first part, the steps of the design process is worked out and the necessary system requirements are analyzed. The second part presents the implementation of the simulationbased determination of the system parameters.
27

Suspensions turbulentes de particules de tailles finies : dynamique, modification collective de l'écoulement turbulent / Finite size particles suspensions in a turbulent flow : dynamic, flow modifications and collectives effects

Cisse, Mamadou 10 April 2015 (has links)
Les travaux numériques et expérimentaux de cette thèse contribuent à une meilleure compréhension de la dynamique de grosses particules dans un écoulement turbulent. Un premier volet m’a permis de quantifier leur mouvement relatif au fluide, ainsi que leur influence locale sur l’écoulement turbulent. Dans un second volet, j'ai trouvé que l'effet collectif des particules est d'atténuer l’amplitude des fluctuations turbulentes. En revanche, celles-ci n’ont pas d’influence sur les propriétés statistiques fines de l’écoulement. Aussi, ces mesures suggèrent l’existence d’une transition de phase dans les grandes échelles de l’écoulement au-delà d’un seuil critique du nombre de particules. / The numerical and experimental work of this thesis contribute to a better understanding of the dynamics of large particles in a turbulent flow. The first part allowed me to quantify their relative motion to the flow and their local influence on the surrounding flow. In a second part, I found that the collective effect of particles is to reduce the amplitude of turbulent fluctuations. In revanche, they have no influence on the fine statistical properties of the flow. Also, these measurements suggest the existence of a phase transition in the larger scales of the flow beyond a critical threshold of the number of particles.
28

Osama’s Body: Death of a Political Criminal and (Re)Birth of a Nation

Schrift, Melissa 02 July 2016 (has links)
Abstract: Some criminal bodies are so saturated with social and political meaning; they achieve an afterlife of symbolic desecration that is both public and celebratory. While the West has a legacy of public execution and bodily display as spectacle, these events were typically meant to be sombre platforms for redemption and moral instruction. Indeed, the abolishment of public execution occurred within the rhetoric of a civilising, modern Western society that purports to treat any death as a sacred event. The announcement of Osama Bin Laden’s death was followed by spontaneous public celebration, official narratives about his death and the management of his body and vivid reproductions of his body in popular culture. This paper explores the public afterlife of Osama Bin Laden in relation to nationalism and political effigy and cultural ambivalence and taboos surrounding the dead body in the West.
29

Development of Diagnostic Tools for Use in a Gas Turbine Engine Undergoing Solid Particulate Ingestion

Olshefski, Kristopher Thomas 30 May 2023 (has links)
Aircraft propulsion systems can be exposed to a variety of solid particulates while operating in either arid or other hazardous environments. For conventional takeoff and landing aircraft, debris can be ingested directly into the gas turbine powerplant which is exposed to the ambient environment. For helicopters and other vertical takeoff and landing (VTOL) aircraft, rotor down wash presents a particular threat during takeoff and landing operations as significant amounts of groundlevel particles can be entrained in the surrounding air and subsequently ingested into the engine. Prolonged exposure to particle ingestion events leads to premature engine wear and, in extreme cases, rapid engine failure. Expanding our current understanding of these events is the first step to enabling engine manufacturers to mitigate these damage mechanisms through novel engine designs. The work described in this dissertation is aimed at increasing the scientific understanding of these ingestion events through the development of two distinct diagnostic instruments. First, an anisokinetic particle sampling probe is designed to be used for in-situ particle sampling inside of a gas turbine engine compressor. Offtake of particles during engine operation in dusty conditions will provide researchers with an improved understanding of particle breakage tendency and component erosion susceptibility. Both experimental and numerical investigations of the probe present a comprehensive realization of probe performance characteristics. Secondly, a novel particle visualization technique is developed to provide users with particle distribution and particle mass flow estimates at the inlet of a gas turbine engine. This technique yields both time-resolved and time-averaged quantities, allowing users to have a comprehensive account of particles entering the engine. / Doctor of Philosophy / Foreign debris ingested into aircraft engines can cause serious damage and degrade their performance. The source of these ingested particles may be from atmospherically suspended ash due to volcanic eruption, high altitude ice crystals, or ground-level sand and dust. Both conventional takeoff and landing aircraft and vertical takeoff and landing (VTOL) aircraft are at risk. In extreme cases, exposure to a particle-laden atmosphere has resulted in catastrophic engine failure and loss of life. For this reason, researchers are intensely focused on mitigating the effects of these harmful particulates. The work described in this dissertation establishes two novel diagnostic capabilities. These are aimed at providing the research community with an increased understanding of how particles enter an aircraft powerplant as well as describe the behavior of these particles as they traverse the initial stages of an engine. The first instrument described is a particle sampling probe which is meant to be inserted into the compressor section of a gas turbine engine. This probe will offtake particles as they enter the engine after they have had an opportunity to interact with the rotating components of the compressor. In doing so, researchers gain an improved understanding of particle breakage tendency and component erosion susceptibility. The second instrument provides a snapshot of particle distribution at the inlet of the engine as well as estimates of total particle mass flow. This capability allows researchers to have a precise understanding of the quantity of ingested material as well as a qualitative understanding of how the inflow distribution of particles looks. Each of the developed tools represent a first step to enabling engine manufacturers to mitigate these damage mechanisms through novel engine designs.
30

Kinematic Simulation for Turbulent Particle-Laden Flows

Murray, Stephen 17 June 2016 (has links)
Kinematic simulation (KS) is a means of generating a turbulent-like velocity field, in a manner that enforces an input Eulerian energy spectrum. Such models have also been applied in particle-laden flows, due to their ability to enforce spatial organization of the fluid velocity field when simulating the trajectories of individual particles. A critical evaluation of KS is presented; in particular, its ability to reproduce single-particle Lagrangian statistics is examined. Also the ability of KS to reproduce the preferential concentration of inertial particles is explored. Some numerical results are presented, in which fluid tracers and inertial particles are transported alternatively by (1) simulated turbulence generated by direct numerical simulation (DNS) of the incompressible Navier-Stokes equations, and (2) KS. The effect of unsteadiness formulation in particular is examined. It is found that even steady KS qualitatively reproduces the continuity effect, clustering of inertial particles, elevated dispersion of inertial particles and the intermittent turbulence velocity signal. A novel method is then motivated and formulated, in which, for input RANS parameters, a simulated spectrum is used to generate a KS field which enforces a target Lagrangian timescale. This method is then tested against an existing experimental benchmark, and good agreement is obtained. / Thesis / Doctor of Philosophy (PhD) / Turbulence arises in an immense variety of industrial and scientific applications; from weather to automotive design; from medicine to nuclear engineering. Because turbulence is chaotic, it is difficult to make accurate predictions of how a turbulent flow will behave in a given scenario. The objective of my research is to find easier ways of accurately modelling turbulence in a certain class of particle-laden flows.

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