Dans les pièces de William Shakespeare, les personnages sont souvent désignés par un nom commun, qui peut indiquer leur statut social (« Le Gentilhomme »), leur métier (« Le Jardinier »), leur origine géographique (« L’Égyptien ») ou encore leurs liens relationnels (« Le Père »). Ces désignations anonymes, c’est-à-dire qui n’attribuent pas de nom propre aux personnages, montrent que Shakespeare favorise une inscription de ces rôles dans une société hiérarchisée et étendue, à l’image du public qui assiste aux spectacles, lui-même composé d’un large spectre social. L’étude de leur identité formelle, à partir de tous les signes identificatoires qui permettent la fabrique des personnages — didascalies, costumes, accessoires, corps et parole —, confirme une conception des personnages anonymes ancrée dans l’identité sociale, au détriment de leur identité personnelle. La généricité du personnage anonyme lui permet alors le plus souvent de se mettre au service des héros nommés ou du groupe social auquel il appartient, suivant le principe de self-effacement, « effacement de soi », pour reprendre les termes de Molly Mahood et de Florence Yoon. Toutefois, le mouvement poétique de Shakespeare le conduit parfois à développer ces rôles qui semblent au premier abord mineurs, en travaillant une tension entre fonctionnalisation et individualisation. Leur rapport à l’altérité leur confère alors une identité interactive, socialement et théâtralement, qui façonne leur raison d’être sur la scène de théâtre. D’un anonymat générique, les personnages peuvent alors s’élever vers la sphère de l’universalité. / In William Shakespeare’s plays, characters are often called by common nouns, which can indicate social status (“Gentleman”), occupation (“Gardener”), geographic origin (“Egyptian”) or relationship (“Father”). This anonymous way of naming, which does not assign personal names to the characters, shows that Shakespeare stresses these parts’ affiliation to a ranked and extensive society, mirroring the audience attending the performance, which itself forms a large social spectrum. The study of their identification, based on all the signs which shape the characters — speech headings, costume, props, body, speech —, reasserts a conception of anonymous characters which highlights their social identity to the detriment of their personal identity. Thus, the genericity of the anonymous characters mainly allow them to support named heroes or their social group, according to the self-effacement principle, as Molly Mahood and Florence Yoon define it. However, Shakespeare’s poetical process leads him to develop parts, that may seem minor at first, by working the tension between their function and their individuality. Their relation to otherness gives them an interactive identity, socially and theatrically, which shapes their raison d’être. From generical anonymity, characters can thus rise up to the realm of universality.

Performanz ist ein zentraler Bestandteil des Designs von Anonymisierungsdiensten. Ihre zunehmende Popularität führt jedoch zu einer hohen Netzwerklast, die unzulängliche Entwurfsentscheidungen imminent macht. Die Anforderungen und die vielschichtige Architektur von Anonymisierungsdiensten machen die Thematik zu einem anspruchsvollen und zugleich inspirierenden Forschungsgegenstand. Die vorliegende Arbeit diskutiert das Design von sogenannten Niedriglatenz-Anonymisierungsdiensten im Allgemeinen und dem Tor-Netzwerk als relevantesten Vertreter im Speziellen. Es werden Lösungen für eine Reihe von Forschungsfragen entwickelt, die allesamt das Ziel verfolgen, diese Overlay-Netzwerke zu verbessern und sicherer zu gestalten. Es entsteht ein fundamentales Verständnis zu Netzwerkaspekten in Anonymisierungs-Overlays, das die Netzwerklast, als vorherrschende Ursache für die schwache Performanz, thematisiert. / Performance is a pivot point in the design of anonymity overlays. Due to their growing popularity, they are faced with increasing load, which makes design problems imminent. The special requirements and complex architecture of anonymity overlays renders the topic a challenging but likewise inspiring object of research. In this work, we discuss the design of low-latency anonymous communication systems in general and the Tor network as the de-facto standard in particular. We develop solutions to a number of research questions, all collectively following the aim of enhancing and securing such networks. By doing this we create a fundamental technical understanding of networking aspects in anonymity overlays and tackle the most prevalent performance issue experienced today: network congestion.

O objetivo deste estudo foi o de acompanhar os caminhos de um serviço em Hospitais e Instituições (HI) da Irmandade de Narcóticos Anônimos (NA) na cidade de Porto Alegre, estado do Rio Grande do Sul (RS), a partir, principalmente, de uma interlocutora principal de pesquisa, membro da NA, e de uma longa experiência de campo da pesquisadora. Trata-se do serviço de “transmissão da mensagem” que ocorre na Penitenciária Feminina Madre Pelletier, em que mulheres membros da NA se deslocam até a Penitenciária para “levar a mensagem de recuperação da Narcóticos Anônimos”, às reclusas. Esse serviço ocorre na Instituição Penitenciária sob o formato de painéis, nos quais estão presentes participantes da NA e mulheres reclusas. Nessas ocasiões, ocorre a “partilha” sobre a “recuperação”, e, para a sua realização, são necessários preparações, treinamentos e movimentações que envolvem tanto a Penitenciária quanto a Irmandade. Para acompanhar os caminhos da “transmissão da mensagem” realizei pesquisa de campo de orientação etnográfica na Irmandade de NA e na Penitenciária. Na Irmandade frequentei reuniões abertas de um grupo da Narcóticos Anônimos existente em Porto Alegre, reuniões de serviço do Subcomitê de Relações Públicas, celebrações e eventos de grupos, realizei entrevistas com homens e mulheres participantes da NA, e, em especial, com a interlocutora principal de pesquisa. Na Penitenciária acompanhei, no ano de 2015, encontros de painéis, realizei entrevistas com agentes penitenciárias, assistente social, e mantive conversas com funcionários da direção. Os resultados desse trabalho indicam que os “caminhos da transmissão da mensagem”, ao perpassarem o ambiente da Penitenciária e durante os painéis - ocasiões conjuntas com as reclusas e outras participantes da Irmandade -, adquirem um significado específico para a interlocutora de pesquisa em sua “recuperação”, pois mobilizam seu passado, presente, “ativa” e “recuperação”. / The objective of this study was to follow the paths of a service in Hospitals and Institutions (HI) of the Fellowship of Narcotics Anonymous (NA) in Porto Alegre, state of Rio Grande do Sul (RS), based mainly on a main speaker of research, member of the NA, and a long researcher's field experience. This is the service "message transmission" that occurs in the Women's Penitentiary Madre Pelletier, in which women members of NA moving to the Penitentiary to "carry the message of recovery in Narcotics Anonymous" the inmates. This service is the Penitentiary Institution under the panels format in which they are participants from NA and women prisoners. On these occasions, is "sharing" on the "recovery", and for its implementation, preparations are needed, training and transactions involving both Penitentiary as the Fellowship. To follow the path of "carrying the message" I conducted ethnographic orientation of field research in the NA Fellowship and Prison. Fellowship attended open meetings of an existing Narcotics Anonymous group in Porto Alegre, service meetings of the Subcommittee on Public Relations, celebrations and events groups, conducted interviews with participants men and women of NA, and in particular with the main interlocutor of research. In Penitentiary I followed, in 2015, panel meetings, conducted interviews with prison officers, social workers, and held talks with officials of direction. The results of this study indicate that the "message transmission paths", the permeates the environment of Penitentiary and during the panel - joint occasions with inmates and other participants of the Fellowship - acquire a specific meaning to the speaker of research in their "recovery" for mobilizing their past, present, "active" and "recovery".

While many jokes and sales of specialty merchandise have been made that make light of consumers who frequently shop and buy (e.g., "When the going gets tough, the tough go shopping," or "I am a shopaholic"), for 18 million Americans suffering from compulsive buying, the process of shopping and buying has caused their lives to literally go out of control. The outcomes of this disease for individuals, families, and business are all negative. In a marketing era of social responsibility, if marketers either knowingly or unknowingly encourage increased consumption among compulsive buyers, potential negative outcomes stand to impact others well beyond the span of the personal psychological and financial situations of individual consumers. The purpose of this study was to explore in depth the structures of human consciousness of compulsive buyers by employing the qualitative research tradition of phenomenology. The study was framed by the social constructivist paradigm where my emphasis was on understanding how the essence of each individual consumer's sense of reality was shaped by her/his particular circumstances and lived experiences. From a theoretical perspective, the study offers an integrated framework by bringing together diverse constructs/data themes from previous research in the fields of psychiatry, psychology, sociology, and marketing. Personality antecedents and short- and long-term consequences of compulsive buying were presented in the framework. The study's research question was, "What are the essential structures of the lived experiences of compulsive buyers?" A criterion-purposive sample, where all participants currently experience or have experienced the phenomenon of compulsive buying, was selected. Data collection and analysis were performed from prolonged engagement at Debtors Anonymous meetings over a 12-month period, plus in-depth interviews from six volunteer participants. Individual participant models of compulsive buying were constructed and juxtaposed against the original theoretical model. Data theme frequencies across participants were tabulated and discussed for comparisons against the theoretical model. Results indicated that while each participant's lived experience of the disease shared most theoretical themes identified by previous research, participants also revealed additional data themes unique to her/him. Marketing implications and recommendations for improved marketing strategy were offered.

Internet and mobile communications have had a profound effect on today's society. New services are constantly being deployed, in which personal data are being processed in return for personally tailored services. While mobile networks lay the groundwork for new innovative services, at the same time they pose numerous privacy challenges. There is the risk that honest citizens participating in mobile communications will have their privacy invaded for "the greater good". We argue that it is highly important that individuals are empowered to retain control over their personal spheres. Thus, the goal of this thesis is to design and evaluate anonymous overlay networks} adapted for mobile networks that allow users to control which information leaves their personal spheres in a mobile communication. Technically, by using an anonymous overlay network, users can communicate with their communication partners without disclosing their network identities. In this thesis, we propose three different anonymous overlay networks tailored for mobile networks. First, two approaches are proposed for anonymous browsing on the mobile Internet, namely mCrowds and a Tor-based approach. By applying theoretical analysis and\,/\,or practical experiments, we show that these approaches offer an appropriate trade-off between the offered degree of anonymity and performance loss. Second, an anonymous overlay network for use in mobile ad hoc networks - Chameleon - is suggested. Besides the actual design of these anonymous overlay networks, this thesis provides novel contributions in other essential areas of privacy protection and anonymous communication. First, also non-technical aspects of privacy protection are thoroughly discussed, including legal, social, and user interface aspects. Second, we survey existing metrics for quantifying anonymity and also propose new ideas regarding anonymity metrics. Third, we review and classify existing mechanisms for anonymous communication in mobile ad hoc networks. Lastly, we also propose a cryptographic technique for building up the user base of an anonymous overlay network in a secure and privacy-friendly manner.

Avidentifierade jobbansökningar är en relativt ny metod som under de senaste åren fått utrymme på den svenska arbetsmarknaden samt på forskningsfältet. Uppmärksamheten av metoden kommer av den tidigare forskning som visar att betydelsen av faktorer som bland annat etnisk bakgrund, kön och ålder är ibland avgörande för vem som kallas till jobbintervju. Därför åsyftar denna studie att undersöka hur rekryterare värderar och använder denna metod samt vilken betydelse avidentifiering har för rekryteringsprocessens utfall.Studien utgår ifrån ett hermeneutistiskt perspektiv och har en kvalitativ ansats. Med hjälp av en komparativ undersökningsdesign och flerfallsstudie som analysmetod behandlas det empiriska materialet, vilket utgörs av fem semistrukturerade intervjuer. Dessa intervjuer skapar tillsammans skapar två fall inom IT och konsultbranschen.Analysen behandlas med hjälp av det teoretiska ramverket vilket består av stämplingsteori samt de analytiska begreppen homosocialitet och etnosocialitet. Detta för att öka förståelsen för hur en sorteringsmetod som baseras endast på formella kriterier, utbildning och arbetslivserfarenheter, fungerar i praktiken. Det har framkommit att vid avsaknaden av faktorerna läggs fokus istället på den individuella kompetensen. Informationen gällande individens kompetens och arbetslivserfarenhet är den del som får mest kritik för att vara för ospecifik. Inom IT branschen har det visat sig att faktorer som ålder och etnicitet är av betydelse vid anställning. Det uppstår även en svårighet då kundinflytandet spelar så stor roll vid rekrytering och skapar en ram av vad som efterfrågas av varje anställd. Det är inte endast avgörande vad rekryterare eller arbetsgivare värderar utan det finns flera aktörer som spelar in vid valet av medarbetare. / Anonymous job applications are a relatively new method that has gained space in the Swedish labor market and the research field in recent years. Research shows that personal attributes are often crucial for who gets called to a job interview. Therefore, this study refers to examine how recruiters evaluate and use this approach and demonstrates the importance that anonymity has to the outcome of the recruitment process.The study is based on a hermeneutic perspective with a qualitative approach and was conducted using a comparative study design, with analysis based on several case studies. The empirical material consists of five semi-structured interviews, which together creates two cases within the IT and consulting industry.During the analysis, a theoretical framework has been presented which consists of the labelling theory and the analytical concepts of homosociality and etnosociality. These three are used to increase the understanding of how a sorting method based only on formal criteria, training and work experience, is used in practice. This has led an employer to focus on individual competency instead of ethnic background, gender or age. However, a problem remains in the industry where age is a determining factor and ethnicity is linked to Swedish language skills. Difficulties also arise when customer influence plays a large role in the recruitment process and this creates a framework of what is expected of every employee. This enables consultants to be adapted depending on the criteria that are necessary for the specific company. It is not only vital what recruiters or employers value but also what the clients wants and expect of the consultants.

PINHO, Silvana de Sousa. Movimentos de Protestos Virtuais da Anonymous no Brasil: unidos como um e divididos por fakes. 2016. 246f. – Tese (Doutorado) – Universidade Federal do Ceará, Programa de Pós-graduação em Sociologia, Fortaleza (CE), 2016. / Submitted by Márcia Araújo (marcia_m_bezerra@yahoo.com.br) on 2016-05-06T14:14:04Z No. of bitstreams: 1 2016_tese_sspinho.pdf: 8339539 bytes, checksum: 4b4aae21a9ed6ebf979919360b7a85b0 (MD5) / Approved for entry into archive by Márcia Araújo (marcia_m_bezerra@yahoo.com.br) on 2016-05-06T15:24:29Z (GMT) No. of bitstreams: 1 2016_tese_sspinho.pdf: 8339539 bytes, checksum: 4b4aae21a9ed6ebf979919360b7a85b0 (MD5) / Made available in DSpace on 2016-05-06T15:24:29Z (GMT). No. of bitstreams: 1 2016_tese_sspinho.pdf: 8339539 bytes, checksum: 4b4aae21a9ed6ebf979919360b7a85b0 (MD5) Previous issue date: 2016 / This thesis, entitled "Movement of virtual protests by the Anonymous in Brazil: united as one and divided by fakes," presents an analytical evaluation of the Anonymous Protests Network, since its inception, in the site 4chan, to show dissent against the World Cup Brazil - 2014, having reached its peak in the June 2013 Demonstrations, in which Anonymous had influential participation, either through online activism practices as in direct actions offline. The ideology supporting Anonymous is characterized by a form of political struggle which aims at achieving human emancipation through hiper-democracy, technocracy and complete freedom of expression, information and communication. The process of a successful establishment of these ideas would take place through the practice of new models of social mobilization, that is, by an autonomous educational process - self-vigilant, anonymous - which would develop a horizontal movement without leaders, without interference from political parties and without ideologies. This model differs from the political form of struggle of the twentieth century, characterized by the traditional split between left and right movements with leaders in a personality vertical hierarchal power line, guided by explicit ideological tendencies. In order to understand the development of the Anonymous protest actions in Brazil, it was used as a empirical research base several virtual sources such as Facebook pages and YouTube channels of Anonymous cells in Brazil and abroad, as well as observation of street protests, such as "Operation September 7" and "Operation No World Cup", besides interviews with Anonymous activists. The process of analysis of the sources was weighted by the study of the contents and the various forms of languages used in the actions of cyberactivists. It was found that the development of political struggles based on ideas spawned by Anonymous, as far as it proposes to break the traditional model of political action, in spite of counting with significant number of activists, the Anonymous ideology was not understood by most of his followers and activists. The very form of creating Anonymous cells in Brazil had a distorted start and was conducted in vertical fashion, anonymity allowing activists to follow plans established by small groups or unknown organizations, as well as appropriation of Anonymous cells by fakes, which led to certain mobilizations guided by political interests of a partisan and ideological nature. This fact resulted in divisions, ruptures and complaints by parts of some cells. As an example of this situation one can cite Anonymous FUEL, which remained active, but with a vigilant stance on Anonymous ideology, and two other branches, Anonymous Paraná and Anonymous Curitiba, which declared themselves inactive, given misrepresentation of Anonymous ideas by other cells that assumed militarist causes and defended a coup d’état in Brazil. For this study, the methodology used had as reference discourse analysis of Bakhetin (2002) and Ducrot (1987). For themes that permeate the study, such as cyberspace, hacktivism, postmodernism and social movements, it was used as a theoretical basis the contributions of Castells (1999), Levy (1999), Melucci (1989), Tilly (1978), Vegh (2003), Harvey (2008), Santos (2000), (2002), Giddens (1991) and Beck (2000). / A presente Tese, intitulada “Movimentos de protestos virtuais da Anonymous no Brasil: unidos como um e divididos por fakes”, apresenta um estudo analítico da Rede de Protestos Anonymous, desde seus primórdios, no site 4chan, até os protestos contra a Copa do Mundo no Brasil - 2014, tendo como ápice as Manifestações de Junho de 2013, nas quais a Anonymous teve influente participação, tanto por meio de práticas de ativismo online quanto em ações diretas, offline. O ideário Anonymous é caracterizado por uma forma de luta política que objetiva alcançar a emancipação humana por meio da hiperdemocracia, tecnocracia, total liberdade de expressão, informação e comunicação. O processo de conquista deste ideário se daria pela prática de novos modelos de mobilizações sociais, ou seja, por um processo educativo autônomo, autovigilante, anônimo, que se desenvolveria num movimento horizontal, sem lideranças, sem interferências de partidos políticos e sem ideologias. Este modelo se diferencia da forma de luta política do século XX, caracterizada pela tradicional dicotomia entre esquerda e direita, movimentos com lideranças verticalizadas, personalistas e guiadas por tendências ideológicas explícitas. No intuito de compreender o desenvolvimento das ações de protestos Anonymous no Brasil, utilizou-se como base empírica de pesquisa diversas fontes virtuais, tais como páginas do Facebook e canais do Youtube das células de Anonymous no Brasil e exterior, além de observação dos protestos de rua, “Operação 7 de setembro” e a “Operação Não vai ter Copa”, e entrevistas com ativistas Anonymous. O processo de análise das fontes foi ponderado pelo estudo dos conteúdos e das diversas formas de linguagens utilizadas nas ações ciberativistas. Verificou-se que o desenvolvimento da luta política com base no ideário Anonymous, na medida em que se propôs a romper com o modelo tradicional de movimento político, apesar de agregar significativo número de ativistas, o ideário Anonymous não foi compreendido pela maioria de seus seguidores e ativistas. A própria forma de criação das células Anonymous no Brasil teve um início desvirtuado, tendo sido conduzido de modo verticalizado, em cujo anonimato permitiu que os ativistas seguissem planos estabelecidos por pequenos grupos ou organizações desconhecidas, bem como a apropriação das células Anonymous por fakes, que conduziram determinadas mobilizações orientadas por interesses políticos, partidários e ideológicos. Tal fato resultou em divisões, rupturas e denúncias por partes de algumas células. Por exemplo, a Anonymous FUEL, que continuou ativa, mas com uma postura vigilante em relação ao ideário Anonymous, bem como as células Anonymous Paraná e Anonymous Curitiba, que se declararam inativas, dadas a deturpação de ativistas Anonymous que passaram a assumir causas militaristas e golpistas. Para fins deste estudo, a metodologia utilizada teve como referência a análise de discurso de Bakhtin (2002) e Ducrot (1987). Para temas que permeiam o estudo, como o ciberespaço, hackerativismo, pós-modernidade e movimentos sociais, utilizou-se como base teórica as contribuições de Castells (2003), Lévy (1999), Melucci (1989), Tilly (1978), Vegh (2003), Harvey (2008), Santos (2000), (2002), Giddens (1991) e Beck (2000).

O objetivo deste estudo foi o de acompanhar os caminhos de um serviço em Hospitais e Instituições (HI) da Irmandade de Narcóticos Anônimos (NA) na cidade de Porto Alegre, estado do Rio Grande do Sul (RS), a partir, principalmente, de uma interlocutora principal de pesquisa, membro da NA, e de uma longa experiência de campo da pesquisadora. Trata-se do serviço de “transmissão da mensagem” que ocorre na Penitenciária Feminina Madre Pelletier, em que mulheres membros da NA se deslocam até a Penitenciária para “levar a mensagem de recuperação da Narcóticos Anônimos”, às reclusas. Esse serviço ocorre na Instituição Penitenciária sob o formato de painéis, nos quais estão presentes participantes da NA e mulheres reclusas. Nessas ocasiões, ocorre a “partilha” sobre a “recuperação”, e, para a sua realização, são necessários preparações, treinamentos e movimentações que envolvem tanto a Penitenciária quanto a Irmandade. Para acompanhar os caminhos da “transmissão da mensagem” realizei pesquisa de campo de orientação etnográfica na Irmandade de NA e na Penitenciária. Na Irmandade frequentei reuniões abertas de um grupo da Narcóticos Anônimos existente em Porto Alegre, reuniões de serviço do Subcomitê de Relações Públicas, celebrações e eventos de grupos, realizei entrevistas com homens e mulheres participantes da NA, e, em especial, com a interlocutora principal de pesquisa. Na Penitenciária acompanhei, no ano de 2015, encontros de painéis, realizei entrevistas com agentes penitenciárias, assistente social, e mantive conversas com funcionários da direção. Os resultados desse trabalho indicam que os “caminhos da transmissão da mensagem”, ao perpassarem o ambiente da Penitenciária e durante os painéis - ocasiões conjuntas com as reclusas e outras participantes da Irmandade -, adquirem um significado específico para a interlocutora de pesquisa em sua “recuperação”, pois mobilizam seu passado, presente, “ativa” e “recuperação”. / The objective of this study was to follow the paths of a service in Hospitals and Institutions (HI) of the Fellowship of Narcotics Anonymous (NA) in Porto Alegre, state of Rio Grande do Sul (RS), based mainly on a main speaker of research, member of the NA, and a long researcher's field experience. This is the service "message transmission" that occurs in the Women's Penitentiary Madre Pelletier, in which women members of NA moving to the Penitentiary to "carry the message of recovery in Narcotics Anonymous" the inmates. This service is the Penitentiary Institution under the panels format in which they are participants from NA and women prisoners. On these occasions, is "sharing" on the "recovery", and for its implementation, preparations are needed, training and transactions involving both Penitentiary as the Fellowship. To follow the path of "carrying the message" I conducted ethnographic orientation of field research in the NA Fellowship and Prison. Fellowship attended open meetings of an existing Narcotics Anonymous group in Porto Alegre, service meetings of the Subcommittee on Public Relations, celebrations and events groups, conducted interviews with participants men and women of NA, and in particular with the main interlocutor of research. In Penitentiary I followed, in 2015, panel meetings, conducted interviews with prison officers, social workers, and held talks with officials of direction. The results of this study indicate that the "message transmission paths", the permeates the environment of Penitentiary and during the panel - joint occasions with inmates and other participants of the Fellowship - acquire a specific meaning to the speaker of research in their "recovery" for mobilizing their past, present, "active" and "recovery".

Dans cette thèse, nous étudions les constructions cryptographiques prouvées pour la protection de la vie privée. Pour cela nous nous sommes intéressés aux preuves et arguments à divulgation nulles de connaissance et leurs applications. Un exemple de ces constructions est la signature de groupe. Ce protocole a pour but de permettre à un utilisateur de s'authentifier comme appartenant à un groupe, sans révéler son identité. Afin que les utilisateurs restent responsable de leurs agissements, une autorité indépendante est capable de lever l'anonymat d'un utilisateur en cas de litige. Une telle construction peut ainsi être utilisée, par exemple, dans les systèmes de transport en commun. Un utilisateur qui rentre dans un bus prouve ainsi son appartenance aux utilisateurs possédant un abonnement valide, sans révéler qui il est, et évitant ainsi que la société de transport ne le trace. En revanche, en cas d'incident sur le réseau, la société peut faire appel à la police pour lever l'anonymat des usagers présents au moment de l'incident. Nous avons proposé deux constructions de ces signatures de groupe, prouvées sûres sous des hypothèses simples dans le monde des couplages et des réseaux euclidiens. Dans la continuité de ces travaux, nous avons aussi proposé la première construction de chiffrement de groupe (l'équivalent de la signature de groupe pour le chiffrement) à base de réseaux euclidiens. Finalement, ces travaux nous ont amené à la construction d'un schéma de transfert inconscient adaptatif avec contrôle d'accès à base de réseaux euclidiens. Ces constructions à base de réseaux ont été rendues possibles par des améliorations successives de l'expressivité du protocole de Stern, qui reposait initialement sur la difficulté du problème du décodage de syndrome. / In this thesis, we study provably secure privacy-preserving cryptographic constructions.We focus on zero-knowledge proofs and their applications.Group signatures are an example of such constructions.This primitive allows users to sign messages on behalf of a group (which they formerly joined), while remaining anonymous inside this group.Additionally, users remain accountable for their actions as another independent authority, a judge, is empowered with a secret information to lift the anonymity of any given signature.This construction has applications in anonymous access control, such as public transportations.Whenever someone enters a public transportation, he signs a timestamp. Doing this proves that he belongs to the group of people with a valid subscription.In case of problem, the transportation company hands the record of suspicious signatures to the police, which is able to un-anonymize them.We propose two constructions of group signatures for dynamically growing groups. The first is based on pairing-related assumptions and is fairly practical. The second construction is proven secure under lattice assumptions for the sake of not putting all eggs in the same basket.Following the same spirit, we also propose two constructions for privacy-preserving cryptography.The first one is a group encryption scheme, which is the encryption analogue of group signatures. Here, the goal is to hide the recipient of a ciphertext who belongs to a group, while proving some properties on the message, like the absence of malwares. The second is an adaptive oblivious transfer protocol, which allows a user to anonymously query an encrypted database, while keeping the unrequested messages hidden.These constructions were made possible through a series of work improving the expressiveness of Stern's protocol, which was originally based on the syndrome decoding problem.

The thesis introduces perception of guilt and sin in the Bible, in Christian tradition and in contemporary moral theology. It emphasizes that in the mentioned periods both phenomena belonged in the common talk and to the elemental moral concepts. It deals with perception of guilt (sin) and forgiveness at present and it does not omit the findings of empirical sciences. It takes into consideration the facts which led to the loss or deformation of awareness of both phenomena in the society in general. In practice it conducts the survey of the possible idea of the contemporary state of awareness of guilt and forgiveness and relates it to the specific group of Anonymous Alcoholics.