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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.
181

Medias skildring av det svenska samhället : En diskursanalys om integration och utanförskap

Engkvist, Johan January 2008 (has links)
<p>Denna uppsats syftar till att tydliggöra de mediala diskurser som finns om integration och utanförskap i tidningsartiklar. Tidningsartiklarna sträcker sig över två tidsperioder, 1996-1997 och 2006-2007. En frågeställning som uppsatsen försöker besvara är om analysens tidningsartiklar går att koppla till Ruth Levitas diskursmodeller om socialt utanförskap. Den centrala teoretiska utgångspunkten är ett postkolonialt perspektiv. Uttrycket ”vi och dem” utgör en röd tråd genom hela uppsatsen. Metoden för analysen är det diskursanalytiska verktyget diskursteori. Uppsatsens analys visar på tre centrala teman där samtliga utgår från utanförskap. Dessa teman är kultur och utanförskap, fördelning och utanförskap samt arbete och utanförskap.</p>
182

Medias skildring av det svenska samhället : En diskursanalys om integration och utanförskap

Engkvist, Johan January 2008 (has links)
Denna uppsats syftar till att tydliggöra de mediala diskurser som finns om integration och utanförskap i tidningsartiklar. Tidningsartiklarna sträcker sig över två tidsperioder, 1996-1997 och 2006-2007. En frågeställning som uppsatsen försöker besvara är om analysens tidningsartiklar går att koppla till Ruth Levitas diskursmodeller om socialt utanförskap. Den centrala teoretiska utgångspunkten är ett postkolonialt perspektiv. Uttrycket ”vi och dem” utgör en röd tråd genom hela uppsatsen. Metoden för analysen är det diskursanalytiska verktyget diskursteori. Uppsatsens analys visar på tre centrala teman där samtliga utgår från utanförskap. Dessa teman är kultur och utanförskap, fördelning och utanförskap samt arbete och utanförskap.
183

Surficial Materials Mapping and Surface Lineaments Analysis in the Umiujalik Lake area, Nunavut, Using RADARSAT-2 Polarimetric SAR, LANDSAT-7, and DEM Images

Shelat, Yask 01 April 2012 (has links)
This thesis is focused on the utilization of RADARSAT-2 polarimetric SAR data for mapping two surficial aspects of the Umiujalik Lake area, Nunavut, Canada: i) materials, such as bedrock, boulders, organic material, sand and gravel, thick and thin till; and ii) lineaments. To achieve these tasks, RADARSAT-2 polarimetric SAR images with three west-looking, increasing incidence angles (FQ1, FQ12, and FQ20, respectively) were used alone and in combination with LANDSAT-7 ETM+ and Digital Elevation Model (DEM) image data. The surficial materials mapping study tested: i) the effects of incidence angles on mapping accuracy; and ii) non-polarimetric and polarimetric classifiers. For non-polarimetric analysis, a Maximum Likelihood Classification (MLC) algorithm was applied to different combinations of RADARSAT-2, LANDSAT-7 ETM+, and DEM images, achieving a maximum overall classification accuracy of 85%. Polarimetric analyses first included computation of polarimetric signatures to understand the scattering mechanisms of the considered surficial materials, i.e., surface, volume, and multiple scatterings. It also tested three polarimetric classifiers: supervised Wishart (overall accuracy of 48.7% from FQ12 image), and unsupervised Freeman-Wishart, and Wishart-H/ /A. Three main conclusions were reached: i) high incidence angle greatly decreases classification accuracy for the HH polarized image when used alone, but incidence angle has little effect when the HV polarization is added; ii) combining images with three incidence angles (FQ1, FQ12, and FQ20) gives higher accuracy with the maximum likelihood classifier; and iii) the medium incidence angle image (FQ12) produces the best classification accuracy using polarimetric classifiers. In the second part of the study, surface lineaments were mapped using RADARSAT-2 SAR single-polarized images, RGB HH, HV, VV composites, polarimetric total power images, and LANDSAT-7 ETM+ principal component images. Polarization effect analysis showed that regardless of beam mode, more lineaments were identified on the HH image than on the HV image, and the maximum number of lineaments was identified on the multi-polarized RGB composite. Incidence angle effects results showed that regardless of polarization modes, the FQ12 image yielded more lineaments than the FQ1 or FQ20 images. The majority of lineaments are oriented in NW and NNW directions, which correspond to the ice flow direction during the last glaciation.
184

Väst om öst : Om andrafierande praktiker och postkoloniala strukturer i historieläroböcker

Nolgård, Olle January 2014 (has links)
Med utgångspunkt i den postkoloniala teoribildningen granskar denna uppsats framställningarna av Asien i gymnasieskolans historieläroböcker för att undersöka hur läroböckerna upprätthåller eller motverkar de orientalistiska- och postkoloniala strukturer vilka beskriver Asien som underordnat väst samt identifierar hur dessa konstruktioner tar sig uttryck. Studien utgår från en ideologikritisk närläsningsstudie av fem läroböcker i historia. Samtliga studieobjekt är publicerade under år 2011 och 2012 inom ramen för den nya läroplanen, gymnasieskola 11, och kursen Historia1b. Analysen genomförs och presenteras via en analysmodell vilken innefattar rubrikerna andrafierande praktiker, över- och underordning, dikotomier och kulturell stratifikation. Resultatet visar att västerlandets hegemoni reproduceras genom i huvudsak eurocentriska diskurser där västerlandet överordnas österlandet eller där en eurocentrisk historieskrivning som berättar en selektiv historia förs i läroboken. Vidare kan av resultatet skönjas en kulturell stratifikation i vilken länder som anammat författningar av västerländska snitt och västerländska sedvänjor värderas högre än länder som inte gjort det. Resultatet visar också att läroböckerna reproducerar alienerande, stundom rasistiska, och pistocentriska schablonbilder och fördomar vilka bidrar till paradigmen om ett vi och ett dem.
185

Modelisation multi-echelle des materiaux granulaires frottant-cohesifs

Nguyen, Trung Kien 17 December 2013 (has links) (PDF)
Ce travail de recherche présente la modélisation du comportement mécanique des matériaux granulaires cohésifs par une approche multi-échelle en combinant la méthode des éléments finis (FEM) et la méthode des éléments discrets (DEM). A l'échelle microscopique, la DEM est utilisé pour modéliser un assemblage granulaire alors qu'à l'échelle macroscopique, la solution numérique est obtenue par la FEM. Afin de faire un pont entre l'échelle micro et macroscopique, un Volume Elementaire Représentative (VER) est considéré dans lequel la contrainte suite à une déformation imposée résulte d'un calcul numérique de type DEM. Par cette manière, la loi numérique constitutive est déterminé par la modélisation de la microstructure, et par conséquent prenant en compte les natures des matériaux granulaires. Après avoir achevé à construire la loi numérique, on propose d'étudier les propriétés de cette loi incrémentale en terme des enveloppes de réponse Gudehus, et des analyses en bande de cisaillement. Cet étude nous permet d'avoir une vision générale sur cette nouvelle loi. Dans cette contribution numérique multi-échelle, en implémentant la loi numérique DEM dans un code de calcul par éléments finis, un outil numérique est obtenu et utilisé à simuler des essais menés au laboratoire. Des résultats obtenus produisant la localisation de la déformation en bandes de cisaillement seront analysés et discutés.
186

Die Arbeitsweise Ödön von Horváths am Beispiel der <Geschichten aus dem Wiener Wald>

Mueller, Ruediger H. January 1993 (has links)
By taking into account various published fragments, concepts and the final 'Volksstuck' this thesis attempts to show how the playwright Odon von Horvath developed the characters of his commercially successful 'Volksstuck' "Tales From The Vienna Woods". Chapter one of this thesis includes a brief biography of Horvath. The second chapter comprises a short history of the 'Volksstuck', Horvaths interpretation of the genre and its implications for his plays as well as a summary of the final version "'Geschichten aus dem Wiener Wald.' Volksstuck in drei Teilen." The thesis further attempts to recreate a genealogy of the dramatic characters Zauberkonig, Alfred, Marianne and Oskar and to give possible reasons for their dramaturgical changes up to the development of the final version. In addition the thesis concerns itself with one example for the development of stage directions. Political as well as religious implications are considered alone and in connection with the characters.
187

Numerical Studies of Frictional Sliding Behavior and Influences of Confining Pressure on Accoustic Activities in Compression Tests Using FEM/DEM

Zhao, Qi 11 December 2013 (has links)
The combined finite-discrete element method (FEM/DEM) has been used to simulate processes of brittle fracturing and associated seismicity. With the newly extended FEM/DEM algorithm, two topics involving rock mechanics and geophysics are investigated. In the first topic, a velocity-weakening law is implemented to investigate the initiation of frictional slip, and an innovative method that incorporates surface roughness with varying friction coefficients is introduced to examine the influences of surface roughness. Simulated results revealed detailed responses of stresses to the propagation of the slip front. In the second topic, acoustic activities induced in confined compression tests are simulated and quantitatively studied using the internal monitoring algorithm in FEM/DEM. It is shown that with increasing confinement, AE events are spatially more concentrated and temporally more separated, accompanied by a decreasing b-value. Moreover, interesting correlation between orientations of cracks and the mechanical behavior of the rock was observed.
188

Numerical Studies of Frictional Sliding Behavior and Influences of Confining Pressure on Accoustic Activities in Compression Tests Using FEM/DEM

Zhao, Qi 11 December 2013 (has links)
The combined finite-discrete element method (FEM/DEM) has been used to simulate processes of brittle fracturing and associated seismicity. With the newly extended FEM/DEM algorithm, two topics involving rock mechanics and geophysics are investigated. In the first topic, a velocity-weakening law is implemented to investigate the initiation of frictional slip, and an innovative method that incorporates surface roughness with varying friction coefficients is introduced to examine the influences of surface roughness. Simulated results revealed detailed responses of stresses to the propagation of the slip front. In the second topic, acoustic activities induced in confined compression tests are simulated and quantitatively studied using the internal monitoring algorithm in FEM/DEM. It is shown that with increasing confinement, AE events are spatially more concentrated and temporally more separated, accompanied by a decreasing b-value. Moreover, interesting correlation between orientations of cracks and the mechanical behavior of the rock was observed.
189

Investigation of Discontinuous Deformation Analysis for Application in Jointed Rock Masses

Khan, Mohammad S. 13 August 2010 (has links)
The Distinct Element Method (DEM) and Discontinuous Deformation Analysis (DDA) are the two most commonly used discrete element methods in rock mechanics. Discrete element approaches are computationally expensive as they involve the interaction of multiple discrete bodies with continuously changing contacts. Therefore, it is very important to ensure that the method selected for the analysis is computationally efficient. In this research, a general assessment of DDA and DEM is performed from a computational efficiency perspective, and relevant enhancements to DDA are developed. The computational speed of DDA is observed to be considerably slower than DEM. In order to identify reasons affecting the computational efficiency of DDA, fundamental aspects of DDA and DEM are compared which suggests that they mainly differ in the contact mechanics, and the time integration scheme used. An in-depth evaluation of these aspects revealed that the openclose iterative procedure used in DDA which exhibits highly nonlinear behavior is one of the main reasons causing DDA to slow down. In order to improve the computational efficiency of DDA, an alternative approach based on a more realistic rock joint behavior is developed in this research. In this approach, contacts are assumed to be deformable, i.e., interpenetrations of the blocks in contact are permitted. This eliminated the computationally expensive open-close iterative procedure adopted in DDA-Shi and enhanced its speed up to four times. In order to consider deformability of the blocks in DDA, several approaches are reported. The hybrid DDA-FEM approach is one of them, although this approach captures the block deformability quite effectively, it becomes computationally expensive for large-scale problems. An alternative simplified uncoupled DDA-FEM approach is developed in this research. The main idea of this approach is to model rigid body movement and the block internal deformation separately. Efficiency and simplicity of this approach lie in keeping the DDA and the FEM algorithms separate and solving FEM equations individually for each block. Based on a number of numerical examples presented in this dissertation, it is concluded that from a computational efficiency standpoint, the implicit solution scheme may not be appropriate for discrete element modelling. Although for quasi-static problems where inertia effects are insignificant, implicit schemes have been successfully used for linear analyses, they do not prove to be advantageous for contact-type problems even in quasi-static mode due to the highly nonlinear behavior of contacts.
190

Accuracy Assessment Of The Dem And Orthoimage Generated From Aster

Ok, Ali Ozgun 01 September 2005 (has links) (PDF)
In this study, DEMs and orthoimages were generated from ASTER imagery and their accuracies were assessed. The study site covers an area of approximately 60 x 60 km and encloses the city of Ankara. First, DEMs were generated from stereo ASTER images. In order to find the best GCP combination, different number of GCPs (8, 16, 24, and 32) was used. The accuracies of the generated DEMs were then assessed based on the check points (CP), slopes and land cover types. It was found that 16 GCPs were good compromise to produce the most accurate DEM. The post processing and blunder removal increased the overall accuracy up to 38%. It was also found that there is a strong linear relationship between the accuracies of DEMs and the slopes of the terrain. The accuracies computed for water, urban, forest, mountainous, and other areas were found to be 5.01 m, 8.03 m, 12.69 m, 17.14 m, and 10.21 m, respectively. The overall accuracy was computed as 10.92 m. The orthorectification of the ASTER image was carried out using 12 different mathematical models. Based on the results, the models First Order 2D Polynomial, Direct Linear Transformation and First Order Polynomial with Relief have produced the worst results. On the other hand, the model Second Order Rational Function appears to be the best model to orthorectify the ASTER images. However, the developed model Second Order Polynomial with Relief provides simplicity, consistency and requires less number of GCPs when compared to the model Second Order Rational Function.

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