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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.
91

Tiggeriets Symboler : En studie om beteende och strategier i en mellansvensk stad

From, David, Arvidsson, Jonas January 2015 (has links)
The purpose of this study was to reveal typical strategies used by beggars in Sweden and how interactions between beggars and passers-by affect behavioral patterns. The study aimed to analyze the results of the observation through a symbolic interactionistic perspective in order to reveal meanings of symbolic interactions in the begging encounter. The study was conducted in an ethnographic manner and the method of use was covert observation. The result showed that there are several types of strategies and symbols used by beggars in Sweden. The most used strategy is the passive, sitting type of begging where signs and photographs are used as symbols to convey distress. The study showed that the use of strategies are general, meaning there is no difference in use of strategies dependent on gender or age.  Furthermore, the study indicated that a connection between begging and organized crime is improbable. Moreover the study showed different counter strategies used by passers-by in the begging encounter. / Syftet med denna studie var att undersöka strategier som används av tiggare i Sverige och hur samspelet mellan tiggare och förbipasserande påverkar beteendemönster. Studien syftade till att analysera resultaten av observationerna med hjälp av ett symbolisk interaktionistiskt perspektiv för att belysa b   betydelser av symboliska interaktioner i mötet med tiggaren. Studien genomfördes i en etnografisk anda där insamlingsmetoden var dolda observationer. Resultatet visade att det finns flera typer av strategier och symboler som används av tiggare i Sverige. Den mest använda strategin är den passiva, sittande typen av tiggeri där skyltar och bilder används som symboler för att förmedla nödställdhet. Studien visade att användningen av strategier är generella, vilket innebär att det inte finns någon skillnad i användning av strategier som är beroende av kön eller ålder. Studien indikerade också att ett samband mellan tiggeri och organiserad brottslighet ter sig osannolikt. Därutöver visade studien olika former av motstrategier som används av förbipasserande.
92

När målet helgar mediet : En kvalitativ fallstudie av dold viral PR / When the objective justifies the choice of medium : A qualitative case study about viral covert PR

Gustafson, Rebecka January 2014 (has links)
Surveys show that consumers tend to avoid traditional marketing channels, leading the practitioners to use earned media channels through public relations (PR). This has also led to the use of covert PR. To understand the use of this communications method, the purpose of this thesis is to study campaigns, which have gained transmission in social media, by investigating how practitioners of three different campaigns motivate the choice to use covert PR. The study is based on a hermeneutic methodology and has an abductive approach. It is carried out by semi-structured elite interviews with six contributors of three different campaigns, using covert PR. The primary data consists of the empery of the interviews, while the secondary data consists of a theoretical framework of excellence in public relations, the PR practice and viral messages. The result of the study indicates the point of view that covert PR has given the campaigns a wider reach. Furthermore the campaigns are described as having gained an extensive viral transmission, which exceeded the expectations of the interviewees. Nevertheless none of the practitioners think they will do a similar campaign again, it seems that they are aware of the risk of covert PR reducing the organisation’s reputation. The analysis also show a contradiction between the interviewees’ position and the presented theory, which might be caused by a perspective on PR as a way of spreading information rather than creating relationships. / Undersökningar visar att konsumenter i allt större utsträckning undviker reklam, vilket har gjort att kommunikationspraktiker i större utsträckning väljer förtjänade kanaler, eller public relations (PR), för att nå sina målgrupper. En följd av det är PR-aktiviteter med dolda avsändare. Med utgångspunkt i den debatt som finns kring metoden är syftet med studien att undersöka PR som fått viral spridning med avseende på hur tre kampanjer utformats och hur praktikerna bakom dessa i efterhand motiverar och resonerar kring valet av dold viral PR. För att få förståelse för fenomenet och varför sådana kampanjer genomförs har studien ett hermeneutiskt förhållningssätt och en abduktiv ansats. Undersökningen har genomförts med en kvalitativ metod genom semistrukturerade elitintervjuer med sex stycken praktiker som jobbat med någon av tre valda kampanjer. Det empiriska materialet i form av intervjuerna utgör studiens primärdata, medan dess sekundärdata består av teorier och tidigare forskning om excellens i public relations, PR i praktiken och viral spridning i sociala medier. Resultatet visar att den dolda avsändaren och dess avslöjande anses bidra till viral spridning. Kampanjerna motiveras med att de nått stora målgrupper, väckt debatt och varit underhållande – och räckvidden har överträffat praktikernas förväntningar. Ändå nämner alla att det inte är önskvärt att förknippas med metoden. Respondenternas utsagor går till viss del emot teorins normativa resonemang, vilket möjligtvis skulle kunna förklaras av en syn på PR som informationsspridande snarare än relationsskapande.
93

Multilinguismo e preconceito na fronteira Porã: um estudo sobre atitudes e crenças linguísticas / Multilingualism and prejudice on Porã border: a study of linguistic attitudes and beliefs / Multilingüismo y prejuicio en la fronteira Porã: un estudio sobre actitudes y creencias lingüísticas

Fiamengui, Ana Helena Rufo [UNESP] 22 August 2017 (has links)
Submitted by Ana Helena Rufo Fiamengui null (ana_hel15@yahoo.com.br) on 2017-09-11T17:50:06Z No. of bitstreams: 1 Fiamengui_AHRF_Tesefinal.pdf: 2306836 bytes, checksum: 6817adf245390e5f5c9b8e026cf2dac3 (MD5) / Approved for entry into archive by Monique Sasaki (sayumi_sasaki@hotmail.com) on 2017-09-12T17:14:27Z (GMT) No. of bitstreams: 1 fiamengui_ahr_dr_sjrp.pdf: 2306836 bytes, checksum: 6817adf245390e5f5c9b8e026cf2dac3 (MD5) / Made available in DSpace on 2017-09-12T17:14:27Z (GMT). No. of bitstreams: 1 fiamengui_ahr_dr_sjrp.pdf: 2306836 bytes, checksum: 6817adf245390e5f5c9b8e026cf2dac3 (MD5) Previous issue date: 2017-08-22 / A realidade escolar fronteiriça, que se mostra muitas vezes conflituosa e, sobretudo, múltipla e problemática, motivou a realização deste trabalho, que teve como intuito discutir e analisar as atitudes e as crenças dos alunos em relação às línguas oficiais na fronteira Porã, especificamente entre as cidades de Ponta Porã, sul de Mato Grosso do Sul, Brasil, e Pedro Juan Caballero, capital do Departamento de Amambay, Paraguai. Para a análise de atitudes, foi empregado um teste baseado principalmente na matched guise technique (técnica dos falsos pares), de Lambert et al. (1960), que envolve gravações de falantes bilíngues, depois avaliadas por respondentes em relação a um número relevante de atributos. Já o teste de crenças, construído a partir da técnica empregada por Barbosa (2009), tomou por base afirmações diversas sobre as línguas fronteiriças gravadas em visitas anteriores, em relação às quais os alunos deveriam exprimir concordância ou discordância. Além desses dois instrumentos metodológicos, que foram posteriormente reduzidos a dados estatísticos, adotamos ainda instrumentos etnográficos para a coleta de dados, mediante observação participante e gravação de entrevistas. Os testes foram aplicados a dez escolas, sendo cinco de cada país, de que fazem parte 324 adolescentes com idade igual ou superior a 14 anos (fase da percepção social para LABOV, 1974 [1964]). O processamento estatístico dos dados do teste de atitudes apontou uma distribuição dos treze atributos em quatro dimensões: caráter, competência, relacionamento e aparência. Os atributos da dimensão da competência mostram uma tendência clara de atribuição de prestígio ao português em detrimento das línguas do Paraguai, mesmo para os adolescentes que estudam nesse país. Já a análise das outras dimensões permite entrever, em algum grau, uma tendência favorável à atribuição de prestígio encoberto ao guarani. O espanhol recebeu, com frequência, notas intermediárias entre os extremos de valorização e estigma, atribuídos ao português e ao guarani, respectivamente. A análise dos dados submetidos à variável “sexo” demonstrou sutilmente haver maior grau de sensibilidade linguística das mulheres, mas, quando correlacionados à variável “idade”, os dados não forneceram um padrão claro de diferenciação, já que adolescentes entre 14 e 16 anos apresentam reações bastante similares. Quando submetidos à variável “grau de bilinguismo”, os dados evidenciam que esse grupo de fatores atua diferentemente em cada uma das quatro dimensões, mostrando-se os respondentes mais sensíveis ao parâmetro da aparência, numa relação diretamente proporcional entre grau de bilinguismo e valores das notas atribuídas. Também o fator “nível socioeconômico” não mostrou diferenciação significativa a ponto de ser possível depreender um padrão único de avaliação, ainda que haja a tendência de adolescentes de nível mais alto atribuírem notas ligeiramente mais baixas. O teste de crenças, em geral, acompanhou os dados do teste de atitudes em termos da atribuição de maior grau de relevância e utilidade ao português e ao espanhol, embora o guarani também seja considerado relevante e funcional na área de fronteira. As entrevistas, por sua vez, subsidiam e explicam os achados dos outros dois testes. Os dados obtidos forneceram um panorama detalhado das atitudes e crenças de adolescentes que estudam nas escolas de cada um dos lados da fronteira e apontaram para a necessidade de se promover um debate sério da questão do multilinguismo, não apenas no contexto de sala de aula, mas também no da comunidade como um todo. / The reality of schools located in borders, which is often conflictual and, above all, multiple and problematic, has motivated the accomplishment of this investigation, that had the purpose of discussing and analyzing students’ attitudes and beliefs regarding the official languages of the Porã border, specifically between the cities of Ponta Porã, south region of the state of Mato Grosso do Sul, Brazil, and Pedro Juan Caballero, capital of the Department of Amambay, Paraguay. For analyzing the students’ attitudes, a test based mainly on Lambert et al. (1960)´s matched guise technique was used, which involves recording bilingual speakers and then evaluate by respondents in relation to a relevant number of attributes. The second test, the belief test, founded on the technique employed by Barbosa (2009), was based on assertions of border languages recorded in previous visits, in which students were expected to agree or disagree with. In addition to these two methodological instruments, which were later reduced to statistical data, we also adopted ethnographic instruments for data collection, through participant observation and interviews. The tests were applied to ten schools, five from each country, in which 324 teenagers aged 14 or older participate (Labov’s Social Perception stage, 1974 [1964]). Statistical processing of the attitude test data pointed to a distribution of the thirteen attributes in four dimensions: character, competence, relationship and appearance. The attributes of the competence dimension show a clear tendency of ascribing prestige to Portuguese to the detriment of Paraguayan languages, even for adolescents who study in this country. On the other hand, the analysis of other dimensions allows us to see a favorable tendency to attribute covert prestige to Guarani in some degree. Spanish frequently received intermediate marks between the extremes of valorization and stigma, attributed to Portuguese and Guarani respectively. The analysis of the data submitted to the variable “sex” showed that there is a slightly higher degree of women linguistic sensitivity, but when submitted to the variable “age”, the data did not provide a clear pattern of differentiation, as adolescents between 14 and 16 years old present quite similar reactions. When submitted to the variable “degree of bilingualism”, the data indicated that this group of factors acts differently in each of the four dimensions, showing the respondents who are more sensitive to the appearance parameter, in a directly proportional relationship between the degree of bilingualism and the values of the attributed scores. Also, the “socioeconomic level” factor didn’t show significant differentiation to the extent that it is possible to see a single pattern of evaluation, although there is a tendency for higher level adolescents to give slightly lower scores. The belief test, in general, followed the attitude test in terms of assigning more relevance and usefulness to Portuguese and Spanish, although Guarani was also considered relevant and functional in the border area. The interviews, in turn, subsidize and explain the findings of the other two tests. The obtained data provided a detailed view of attitudes and beliefs of adolescents who study in schools from each side of the border and pointed the need to promote a serious debate on multilingualism, not only in the context of the classroom but in the community as well. / La realidad escolar fronteriza, que se muestra muchas veces conflictiva y, sobre todo, múltiple y problemática, motivó la realización de este trabajo, que tuvo como propósito discutir y analizar las actitudes y creencias de los alumnos en respecto a las lenguas oficiales de la frontera Porã, precisamente entre las ciudades de Ponta Porã, sur del estado de Mato Grosso do Sul, Brasil, y Pedro Juan Caballero, capital del Departamento de Amambay, Paraguay. Para el análisis de las actitudes, se empleó un test basado principalmente en el matched guise technique (técnica de pares ocultos), de Lambert et al. (1960), que implica grabaciones de hablantes bilíngües, que son evaluadas por respondedores en relación a un número relevante de atributos. El test de creencias, construido a partir de la técnica empleada por Barbosa (2009), tomó por base diversas afirmaciones sobre las lenguas fronterizas grabadas en visitas anteriores, en relación a las cuales los alumnos deberían expresar concordancia o discordancia. Además de esos dos instrumentos metodológicos, posteriormente reducidos a datos estadísticos, adoptamos también instrumentos etnográficos para la recolección de datos, mediante observación participante y grabación de entrevistas. Los tests se aplicaron a diez escuelas, siendo cinco de cada país, de las que forman parte 324 adolescentes con edad igual o superior a 14 años (fase de la percepción social para LABOV, 1974 [1964]). El procesamiento estadístico de los datos del test de actitudes indicó una distribución de los trece atributos en cuatro dimensiones: carácter, competencia, relación y apariencia. Los atributos de la dimensión de la competencia muestran una tendencia clara de atribución de prestigio al portugués en detrimento de las lenguas de Paraguay, incluso para los adolescentes que estudian en ese país. El análisis de las otras dimensiones permite entrever, en cierto grado, una tendencia favorable de atribución de prestigio encubierto al guaraní. El español recibió con frecuencia notas intermedias entre los extremos de valoración y estigma, atribuidos respectivamente al portugués y al guaraní. El análisis de los datos sometidos a la variable “sexo” demostró sutilmente mayor grado de sensibilidad lingüística de las mujeres, pero cuando relacionados a la variable “edad”, los datos no producen un patrón claro de diferenciación, pues los adolescentes entre 14 y 16 años presentan reacciones muy similares. Cuando se someten a la variable “grado de bilingüismo”, los datos evidencian que ese grupo de factores actúa diferentemente en cada una de las cuatro dimensiones, mostrándose los respondedores más sensibles al parámetro de la apariencia, en una relación directamente proporcional entre grado de bilingüismo y notas atribuidas. También el factor “nivel socioeconómico” no mostró diferenciación significativa hasta el punto de ser posible deducir un único patrón de evaluación, aunque los adolescentes de nivel más alto tiendan a atribuir notas ligeramente más bajas. El test de creencias acompañó en general los datos del test de actitudes en términos de atribución de mayor grado de relevancia y utilidad al portugués y al español, pese a que el guaraní también se considere relevante y funcional en el área fronteriza. Las entrevistas, a su vez, subsidian y explican los hallazgos de los otros dos tests. Los datos obtenidos proporcionaron un panorama detallado de las actitudes y creencias de adolescentes que estudian en las escuelas de cada lado de la frontera y señalan la necesidad de promover un debate serio sobre el multilingüismo no sólo en el contexto del aula sino también en el de la comunidad como un todo.
94

A Study on the Artemis Fowl Series in the Context of Publishing Success

Lindve, Katarina January 2007 (has links)
A close reading of a series of books by Eoin Colfer that enjoyed universal success showed a change in the language between the books especially with respect to minor linguistic features such as choice of location and abstract vs. concrete language. The books are about the boy Artemis Fowl, and were presumably conceived as children’s books. My original thesis was that the writer could not be sure of the success of the first book, but would definitely be aware of a worldwide audience for at least his third book, due to, for example, questions raised by the translators. If the original audience was expected to be Irish, or British, with very much the same cultural background as the author’s, the imagined subsequent audiences would change with success. My hope was to be able to show this by comparing linguistic features. And indeed, even though some changes could be due to coincidence there was a specific pattern evolving in the series, in that the originally Irish cultural background became less exclusive and more universal. The writer also used more details concerning locations, with added words to specify a place. What could thus be expected in the translated versions would be omissions and additions in especially the first book, but less need for that in later books. This, however, could not be proven in the Swedish translations. I thus conclude that the books became easier to follow for a wider, in this case Swedish, audience mostly because of efforts by the author and less because of the translator.
95

Vícejazyčnost a překladovost v jazykové krajině centra Prahy / Multilingual and Translated Elements in the Linguistic Landscape of Prague's City Centre

Herold, Kryštof January 2018 (has links)
Exploring theoretical intersections of translation studies and linguistic landscape studies, this thesis both sums up existing research and presents new ideas, so as to show how the two disciplines can benefit from each other. The main focus of the first chapter is distinctive features of translations in linguistic landscape. The empirical part has several aims. The linguistic landscape of Prague's city centre is examined, above all the use of foreign languages and translations on signs, employing some of the theoretical concepts from the first chapter. The thesis also looks into translativity in linguistic landscape. A selection of translations from Czech to English is then assessed by language specialists who are native speakers of English, helping us identify flaws in the translations.
96

The knowledge and cognitive process dimensions of technology teachers’ lesson objectives

Mathumbu, David January 2013 (has links)
The knowledge and cognitive process dimensions of Technology teachers’ lesson objectives This study employs both quantitative and qualitative enquiry, which seeks to establish the nature and quality of the lesson objectives intended by Technology teachers. Technology teachers are frequently faced with the need to use technological knowledge and its methodological approaches in their development of lesson plans and in their teaching. The methodological aspect and technological knowledge of these teachers should be reflected in the framing of lesson plans containing explicit statements of lesson objectives or learning outcomes. The cognitive levels to which the objectives lead are important because of the demands placed on learners by the subject of technology. Technology inherently requires mastery of some scientific knowledge, and procedures of the technological process from needs establishment to design and fabrication of artefacts. This requires learners to achieve at the upper levels of Bloom‟s taxonomy. This is the important goal of education. The purpose of this study was to investigate the knowledge and cognitive process dimensions of the lesson objectives in lesson plans of Technology teachers. These dimensions of Technology teachers‟ lesson objectives were mapped using the Taxonomy Table adapted from the Revised Bloom‟s Taxonomy. This study used a primarily qualitative research approach, with some quantitative analysis of data. A survey research design with limited scope was used to obtain lesson plans from Technology teachers in order to establish the nature and qualities of their lesson objectives. Lesson plans were collected from 19 teachers in three districts of Mpumalanga. These lesson plans were analysed, interpreted and discussed with sampled teachers in a focus group. With regard to the knowledge and cognitive domains of the Technology teachers‟ lesson objectives, findings from this study suggest that teachers tend to focus more on factual knowledge and less towards metacognitive knowledge, and operate at low-order level in the cognitive domain. In other words, technology learners are being taught factual knowledge at the low-order level of thinking. Technology teachers tend to have lesson objectives that are known only to them. This might imply that teaching in technology occurs without proper specific objectives. Measures need to be put in place to intensify support to Technology teachers so that they realise the importance of the formulation of lesson objectives that cover all the levels in the knowledge and cognitive domains. Furthermore, Technology teachers should be encouraged to state their lesson objectives explicitly. / Dissertation (MEd)--University of Pretoria, 2013. / gm2014 / Science, Mathematics and Technology Education / unrestricted
97

Saccades oculaires, adaptation sensori-motrice et attention visuo-spatiale / Saccades, sensorimotor adaptation and visuo-spatial attention

Habchi, Ouazna 14 December 2015 (has links)
L'interaction des individus avec l'environnement statique ou dynamique nécessite une exploration détaillée et précise des objets. Pour cela, notre système oculomoteur produit des mouvements oculaires rapides et précis appelés « saccades » afin de ramener l’image des objets d’intérêt sur la petite zone centrale de notre rétine (fovéa). Toutefois, notre système oculomoteur est fréquemment exposé à des perturbations physiologiques ou pathologiques. Ces changements sont contrôlés en permanence par des processus sensori moteurs basés sur la plasticité neuronale et appelés adaptation saccadique. L’objectif de mes travaux de thèse est de mieux comprendre les caractéristiques de cette adaptation et sa rétention à long terme mais aussi les réseaux impliqués dans l’adaptation saccadique. Comme les saccades oculaires ont un lien étroit avec l’attention visuo-spatiale, notre intérêt s’est également porté sur les interactions qui peuvent exister avec les réseaux impliqués dans le contrôle de l’attention visuo-spatiale. Un des principaux résultats est que l’orientation de l’attention exogène covert -sans bouger les yeuxdans des taches de détection et de discrimination est améliorée après l’adaptation des saccades réactives. Ces données fondamentales pourraient mener au développement de nouvelles méthodes de rééducation des déficits visuo-attentionnels / The interaction of human beings with their static or dynamic environment requires detailed and precise exploration of objects. For this, our oculomotor system produces fast and accurate eye movements called "saccades" to bring the image of objects of interest on the small central area of the retina (fovea). However, our oculomotor system is frequently exposed to physiological or pathological disturbances. These changes are continuously monitored by sensorimotor processes based on neuronal plasticity and called "saccadic adaptation". The aim of my thesis is to better understand the characteristics of this adaptation and its long-term retention but also the neural networks involved in saccadic adaptation. As saccadic eye movements are closely related to visuo-spatial attention our work has also addressed the interactions that may exist with the networks involved in the control of visuo-spatial attention. A major result revealed that the orientation of the 'covert' exogenous attention -without moving the eyes- in detection and discrimination tasks is improved after adaptation of reactive saccades. These basic data could give rise to the development of new rehabilitation methods in visual-attention deficits
98

Kriminální sítě: aktéři, mechanismy a struktury / Criminal networks: actors, mechanisms, and structures

Diviák, Tomáš January 2020 (has links)
Social network analysis is a fruitful approach to the study of relations and interaction between actors involved in organized crime. This dissertation utilizes network perspective to study several cases of organized criminal groups. It is divided into eight chapters. The first introductory chapter is followed by a chapter reviewing the most important network concepts, measures, and models, and their application in the study of organized crime. The four subsequent chapters are empirical studies. The third chapter is a case study of a political corruption network, known as the Rath affair. The study shows that the network consists of different, sometimes overlapping, relations (multiplexity), namely collaboration, resource transfer, and pre-existing ties. The network shows a clear core-periphery structure with politicians forming a dense core and businesspeople occupying periphery. The following chapter studies a case of counterfeit alcohol distribution network, known as the methanol affair. The network structure is composed of two subgroups bridged by one tie, permitting relatively efficient distribution of the beverages. Furthermore, statistical models point out the importance of triadic closure and pre-existing ties for the formation of ties in the network. The fifth chapter tests an influential theory in...
99

What essentially might be almost certain about climate change : The translation of hedges in popular science

Hamberg, Sofia January 2022 (has links)
This study investigates how hedges are used in an American popular science text about the effects of climate change and to what extent their translation to Swedish is retained or modified concerning modal strength. Furthermore, the study seeks to explain the reasons behind translation choices, which affect the level of modal strength and or linguistics alterations in the target text. The method is both quantitative, where the instances of hedging in the source text are counted and categorized, and qualitative, where potential factors affecting the translation choices are analyzed and interpreted. The results of the study show that hedging devices for the most are retained in translation concerning modal strength. However, an exception is the English modal verb may where the modal strength in six out of eight instances is higher in the target text than in the source text. This study suggests that the vague meaning of modal verbs and the fact that Swedish does not have one apparent translation, with a similar grammatical pattern, could have affected the translation choices. Furthermore, linguistic and text conventional adaptions to the target language may be another factor affecting modifications.
100

Fuites d'information dans les processeurs récents et applications à la virtualisation / Information leakage on shared hardware : evolutions in recent hardware and applications to virtualization

Maurice, Clémentine 28 October 2015 (has links)
Dans un environnement virtualisé, l'hyperviseur fournit l'isolation au niveau logiciel, mais l'infrastructure partagée rend possible des attaques au niveau matériel. Les attaques par canaux auxiliaires ainsi que les canaux cachés sont des problèmes bien connus liés aux infrastructures partagées, et en particulier au partage du processeur. Cependant, ces attaques reposent sur des caractéristiques propres à la microarchitecture qui change avec les différentes générations de matériel. Ces dernières années ont vu la progression des calculs généralistes sur processeurs graphiques (aussi appelés GPUs), couplés aux environnements dits cloud. Cette thèse explore ces récentes évolutions, ainsi que leurs conséquences en termes de fuites d'information dans les environnements virtualisés. Premièrement, nous investiguons les microarchitectures des processeurs récents. Notre première contribution est C5, un canal caché sur le cache qui traverse les coeurs d'un processeur, évalué entre deux machines virtuelles. Notre deuxième contribution est la rétro-ingénierie de la fonction d'adressage complexe du dernier niveau de cache des processeurs Intel, rendant la classe des attaques sur les caches facilement réalisable en pratique. Finalement, dans la dernière partie nous investiguons la sécurité de la virtualisation des GPUs. Notre troisième contribution montre que les environnements virtualisés sont susceptibles aux fuites d'informations sur la mémoire d'un GPU. / In a virtualized environment, the hypervisor provides isolation at the software level, but shared infrastructure makes attacks possible at the hardware level. Side and covert channels are well-known issues of shared hardware, and in particular shared processors. However, they rely on microarchitectural features that are changing with the different generations of hardware. The last years have also shown the rise of General-Purpose computing on Graphics Processing Units (GPGPU), coupled to so-called cloud environments. This thesis explores these recent evolutions and their consequences in terms of information leakage in virtualized environments. We first investigate the recent processor microarchitectures. Our first contribution is C5, a cross-core cache covert channel, evaluated between virtual machines. Following this work, our second contribution is the reverse engineering of the complex addressing function of the last-level cache of Intel processors, rendering the class of cache attacks highly practical. In the last part, we investigate the security of GPU virtualization. Our third contribution shows that virtualized environments are susceptible to information leakage from the GPU memory.

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