La réduction de la résistance à l'avancement par des techniques de contrôle active sera une nécessité d'importance croissante dans les années à venir pour le secteur des transports. Cette thèse fait partie d'une nouvelle voie de recherche consistant à utiliser des décharges plasmas à pression atmosphérique pour modifier les écoulements en vue d'améliorer les performances aérodynamiques (diminution de la traînée et augmentation de la portance). L'actionneur retenu est une décharge à barrière diélectrique surfacique avec un diélectrique composé d'une combinaison de deux matériaux polymères souples. L'écoulement induit par l'actionneur plasma, appelé vent ionique, est d'abord étudié expérimentalement dans l'air au repos en fonction du régime de la décharge. Une loi empirique liant la vitesse du vent ionique à la tension et à la fréquence de l'alimentation est proposée. De cette loi se dégagent une vitesse et une longueur caractéristiques utilisées pour prédire les principales propriétés du jet de paroi induit en aval de la décharge (lois d'échelle). L'efficacité de l'actionneur est ensuite testée en soufflerie subsonique pour trois configurations aérodynamiques de complexité croissante : couche limite laminaire non décollée (plaque plane), couche limite turbulente décollée (profil épais) et couche limite décollée 3D (corps de Ahmed, lunette inclinée à 25°). Des résultats significatifs tant sur le plan de la modification de la topologie de l'écoulement que de l'amélioration des efforts aérodynamiques sont obtenus pour des nombres de Reynolds jusqu'à 1,7.106 (35 m/s).

De nouvelles connaissances sur les écoulements autour des véhicules automobiles doivent aujourd'hui être apportées pour envisager une amélioration de leurs performances aérodynamiques. Ce travail de thèse repose sur des études expérimentales, réalisées en soufflerie, permettant l'analyse et la compréhension des mécanismes physiques associés aux écoulements décollés tridimensionnels et instationnaires se développant à l'arrière des véhicules automobiles. Il se concentre plus particulièrement sur la géométrie générique du corps de Ahmed permettant de reproduire les écoulements à l'arrière de véhicule de type bicorps (lunette arrière et culot). L'étude compare deux maquettes de géométrie différente dont l'une permet d'obtenir une zone de recirculation tridimensionnelle sur la lunette arrière et l'autre de conserver l'écoulement attaché. L'analyse et la comparaison des topologies moyennes des écoulements permettent d'évaluer les interactions entre la recirculation 3D et les autres structures en présence. On montre plus particulièrement que l'absence du décollement sur la lunette arrière modifie la topologie de l'écoulement à l'arrière du culot avec une réduction de traînée de l'ordre de 10%. Les résultats montrent que les effets de la recirculation ne sont pas assez importants pour modifier la position des structures tourbillonnaires longitudinales se développant sur les arêtes latérales de la lunette, mais modifient légèrement leur intensité. L'analyse spectrale des fluctuations de vitesse et de pression indique que la recirculation est le siège d'activités instationnaires pseudopériodiques. La Décomposition Orthogonale Propre des champs de vitesse et de pression montre finalement que ces activités sont associées à un mécanisme de battement de la recirculation passant d'une configuration décollée à une configuration attachée et à une émission de structures tourbillonnaires formées par la couche cisaillée de la recirculation.

The aim of this paper is to examine how women who mosh to hardcore music understand moshing as a meaning making activity and how they understand and negotiate body, gender and space in their relation to moshing. I have done a feminist phenomenological analysis on four deep interviews with women who mosh based on the theories of Sara Ahmed and Iris Young. I have found that my informants discuss moshing in terms of feelings of adrenaline, euphoria, strength and emotional ventilation. They break the norms of female bodily performance at the same time as they feel uncomfortable with how their bodies stand out in relation to the white and male bodies as a norm in hardcore spaces. The women then use how their own and other bodies that stand out as a way to access space and as a ground for resistance, both against the room as masculine and as white. The women show a clear feministic orientation and use a violent bodily performance as a feminist practice.

Ce travail a pour corpus central les œuvres musicales de trois compositeurs contemporains d’origine arabe : Ahmed Essyad, Zad Moultaka et Saed Haddad. Les démarches compositionnelles de ceux-ci ont en commun qu’elles s’inscrivent dans la pensée critique propre à la modernité musicale occidentale, tout en réinvestissant certains matériaux et procédés dérivés de musiques traditionnelles orales du monde arabe. Aussi le matériau emprunté à la musique orale se trouve à la fois déployé et néanmoins contrarié dans ce qu’il pouvait induire comme conduite normative. Dès lors, l’élément musical de la culture d’origine advient en se transformant, et laisse émerger ce faisant de nouvelles potentialités, quitte à devenir alors non-immédiatement perceptible.En analysant les différents processus d’un tel devenir, ce travail interroge la notion de tradition musicale et, à travers elle, la catégorie de l’identité. Les grands bouleversements socioculturels observés depuis l’époque industrielle ont si profondément atteint les pratiques musicales orales que de telles catégories – tradition et identité – ne peuvent plus se présenter que comme problématiques. Ce travail entend rendre compte du fait que le rapport au patrimoine musical peut s’avérer être d’autant plus vif et fructueux dès lors qu’il s’affranchit de l’impératif identitaire. Dans cette perspective, la contemporanéité est envisagée comme distance critique essentielle par rapport à ce qui se présente comme immédiatement donné, y compris son propre acquis culturel ; son champ opératoire devient a fortiori la relation. Ces réflexions sont, du reste, inspirées d’auteurs comme Theodor Adorno, Walter Benjamin et Édouard Glissant. / The central corpus of this work consists of three contemporary composers of Arab origin: Ahmed Essyad, Zad Moultaka et Saed Haddad.Their compositional approaches have a shared basis in the critical thought of western musical modernity, while at the same time they reinvest certain materials and processes derived from traditional oral music of the Arab-Berber world. In addition, the material borrowed from oral music is both deployed and yet thwarted in what it could induce as normative conduct. Consequently, the musical element of the culture of origin occurs by transforming itself, and lets emerge new potentialities, which may not be immediately perceptible.Analyzing the different processes of such a development, this work interrogates the notion of traditional music as well as the category of identity contained within. The major socio-cultural upheavals witnessed since the industrial period have so profoundly affected these oral musical practices that such categories – tradition and identity – must be viewed as problematic. This work intends to account for the fact that the relation to musical heritage can prove to be all the more lively and fruitful as soon as it breaks with the imperative of identity. From this perspective, contemporaneity is envisaged as a critically essential distance in relation to that which presents itself as immediately given, including its own cultural heritage. Its operative field becomes the a fortiori relation. These reflections are influenced by the work of thinkers such as Theodor Adorno, Walter Benjamin and Édouard Glissant.

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Med utgångspunkt i sin kandidatutställning behandlar Elsa Essinger i den här essän tankar kring rörelse i det urbana stadsrummet, abstrahering av grafisk kommunikation i det offentliga, konstnärlig remixing av befintligt material och ett queert förhållningssätt till objekt. Med referenser och inspiration hämtat från Nicolas Bourriauds essä Postproduction, Lars Arrhenius verk The Street och Sara Ahmeds föreläsning Queer Use utforskar Essinger teman och tankeställningar som ligger till grun för hennes konstnärliga arbete.

This study examines if the process of democratic backsliding is observable in the discursive patterns of a government that is the driving force of democratic erosion which can be useful when attempting to discern if a government has undemocratic ambitions. The actor analyzed to answer the research question is the government of Ethiopia. Three hypotheses have been developed based on Levitsky and Ziblatt’s model of democratic backsliding and from these, an analytical framework containing a set of questions has been developed. The questions have been used to systematically analyze the source material. This study found that the Ethiopian government framed those in law and law enforcement agencies and other opposition it perceives as adversaries as illegitimate actors while glorifying and legitimizing their own. In addition, the study found that the government argued that criticism directed at it not following laws or the constitution was either from an illegitimate source or not based on facts.

The purpose of this study is to shed light on how masculinity is portrayed in the selected material, namely the Här kommer [...] series where Halvan is the main character. The study intends to answer the question of what type or types of masculinities that may take up most space and what thatmight mean. To get aswers to the studys questions, three theories are used - temporality and lifelines based on Ahmeds (2006) and Halberstams (2005) theories concerning time and the expected timeline, the hegemonic masculinity with Connell (2008) and the theory of the gender equal Swedish man by Gottzén and Jonsson (2012). The study is based on a qualitative content analysis as well as an image analysis where the material consisted of all books from the series, with a focus on a few selected scenes where I found that the studys questions could be answered. The study found that Halvans daydreams about the fututre are based on norms and expectations regarding the expected timeline, which is based around heteronormativity, among other things. Halvans masculinity also differs from other men in the books where the book series present the idea of the gender equal Swedish man as desirable and normative. This and Halvans desire for vehicles and technology together constitute the ultimate masculinity. The portrayal of masculinity has changed through the book series in that Halvan has been allowed to take up somewhat less space. His colleagues with their vehicles and tasks have been given more space, however, Halvans own maskulinity has become clearer and we can see more noticeable traces of the Swedish hegemonic masculinity in Halvans character.

In this thesis I interview three Swedish-born or raised racialized gay and bisexual individuals. The purpose is to examine the interviewees' experiences of being racialized and gay/bisexual in Sweden, and how they handle their experiences on an individual level. To do so I use queer theory and Sara Ahmed's phenomenology.I find that whiteness plays a crucial role in the interviewees' lives. Due to a homonationalistic logic, the interviewees are often assumed to be heterosexual. At the same time, a homonationalistic logic leads them closer to whiteness and sometimes enables them to pass as white when “coming out” as gay or bisexual. Furthermore, I find that dating white can serve both as a protection against racism and generate benefits, while it also comes with a risk in form of racism, fear of racism or lack of support when exposed to racism. These experiences have led some of the interviewees to date mainly racialized people as a form of resistance. The thesis also shows that the interviewees often feel excluded in LGBTQ gatherings and places due to being racialized, but at the same time feel safe in relation to their sexuality. All interviewees raise antiracist organization as a way of handling the feeling of being out of place in white LGBTQ-contexts.

Testing done on the flat-back Ahmed Body and other bluff bodies has shown the existence of a bi-stable reflectional symmetry-breaking wake at Reynolds numbers ranging from 340 to 2.41 x 106. Several methods of flow control, both active and passive, have been used to improve the efficiency of the Ahmed body but their effect on the bi-stable nature of the wake has not been investigated. This work details the experimental investigation done to determine if piezoelectrically driven synthetic jet actuators are capable of suppressing the bi-stable wake effects observed behind the Ahmed Body. The synthetic jets were designed and manufactured to have a maximum total coefficient of momentum of 1.0E-3 with a frequency range up to 2000 Hz or F+ = 17.25. The piezoelectric actuators used were bimorph bending disks with no center shim and were driven by a square waveform. Pressure data was collected from 25 pressure ports on the rear of the model at 625 Hz for 600 seconds per run and filtered using a lowpass filter at 35 Hz to remove interference. Center of Pressure probability distributions and Principle Component Analysis were used to identify wake shapes and modes. Results with no jet actuation showed good agreement with previously published work on the Ahmed Body. It was found that the actuation frequency had an effect on the ability of the synthetic jets to affect the wake. Actuating at F+ = 1 (116 Hz) showed a bi-stable wake with an even distribution between wake modes. Higher actuation frequencies showed either a skewed distribution with a weakening of the bi-stable effects (4 < F+ < 8) or a complete removal of the bi-stable distribution (8 < F+ < 12). Frequencies higher than F+ = 12 did not show any effect on the bi-stable distribution. There was a negative correlation between actuation frequency and average wake pressure; it is theorized that the synthetic jets enhance mixing in the shear layer around the recirculation bubble in the wake to decrease average pressure.