abstract: This thesis aims to investigate the capacity and bit error rate (BER) performance of multi-user diversity systems with random number of users and considers its application to cognitive radio systems. Ergodic capacity, normalized capacity, outage capacity, and average bit error rate metrics are studied. It has been found that the randomization of the number of users will reduce the ergodic capacity. A stochastic ordering framework is adopted to order user distributions, for example, Laplace transform ordering. The ergodic capacity under different user distributions will follow their corresponding Laplace transform order. The scaling law of ergodic capacity with mean number of users under Poisson and negative binomial user distributions are studied for large mean number of users and these two random distributions are ordered in Laplace transform ordering sense. The ergodic capacity per user is defined and is shown to increase when the total number of users is randomized, which is the opposite to the case of unnormalized ergodic capacity metric. Outage probability under slow fading is also considered and shown to decrease when the total number of users is randomized. The bit error rate (BER) in a general multi-user diversity system has a completely monotonic derivative, which implies that, according to the Jensen's inequality, the randomization of the total number of users will decrease the average BER performance. The special case of Poisson number of users and Rayleigh fading is studied. Combining with the knowledge of regular variation, the average BER is shown to achieve tightness in the Jensen's inequality. This is followed by the extension to the negative binomial number of users, for which the BER is derived and shown to be decreasing in the number of users. A single primary user cognitive radio system with multi-user diversity at the secondary users is proposed. Comparing to the general multi-user diversity system, there exists an interference constraint between secondary and primary users, which is independent of the secondary users' transmission. The secondary user with high- est transmitted SNR which also satisfies the interference constraint is selected to communicate. The active number of secondary users is a binomial random variable. This is then followed by a derivation of the scaling law of the ergodic capacity with mean number of users and the closed form expression of average BER under this situation. The ergodic capacity under binomial user distribution is shown to outperform the Poisson case. Monte-Carlo simulations are used to supplement our analytical results and compare the performance of different user distributions. / Dissertation/Thesis / M.S. Electrical Engineering 2012

Modern Administrative Law must be considered within the Social and Democratic Rule of Law. Citizens, as users of services of general interest, are at the centre of all the categories of Regulatory Law. They have a legal status that enables them to be present in the decisions that affect them and they can contest decisions that harm their rights. / El Derecho Administrativo moderno debe enmarcarse en el Estado Social y Democrático de Derecho. Los ciudadanos, usuarios de los servicios de interés general, ocupan un lugar central en todas las categorías del Derecho Regulatorio. Disponen de un estatuto jurídico que les permite estar presentes en las decisiones que le afectan y poder impugnar las decisiones que lesionen sus derechos.

Magister Curationis - MCur / Mental health care for adolescents is currently provided in a range of settings world-wide. These include the pediatrics units, general hospitals and specialized in-patient units for adolescents. However, care in these specialized units has hitherto not been evaluated. A phenomenological approach as a method and design was chosen to enable participants to describe and explore the lived experiences of nurses caring for adolescents in specialized psychiatric units of the selected psychiatric hospital. A purposive sampling method was used to select respondents. In-depth interviews were conducted with nurses caring for adolescents with mental health problems. Data saturation was reached with seven respondents. Interviews were recorded with a tape recorder that was only accessible to the researcher. Data analysis followed Collazi’s style that included listening to the recorded data, transcribing, coding, and intuition, reflection, reducing and interpreting the data. Ethical clearance was obtained from University of the Western Cape Higher Degrees Committee. The researcher requested permission to conduct the study at selected Psychiatric hospital from the Medical Superintendent and research ethics committee. Informed consent was also sought for those who agreed to participate in the study. Participants remained anonymous as their identity was not revealed. Only information related to the study was collected. Anonymity was assured by omitting names from transcripts as participants were given numbers only rather than using their names. The in-depth interviews were conducted in a quiet office to ensure privacy and confidentiality.

Este trabalho propõe um método para avaliação das condições de fluidez do tráfego em vias arteriais da cidade de Porto Alegre sob a ótica de seus usuários, de modo a subsidiar a apresentação destas informações através dos painéis de mensagem variável (PMV). Para atingir o objetivo proposto, foram levantados: (i) estado-da-arte e da prática sobre a utilização de PMV; (ii) características das vias arteriais da cidade; (iii) imagens de vídeo e dados de tráfego destas vias; (iv) a percepção dos usuários sobre a fluidez do tráfego. O levantamento do estado-da-arte e da prática permitiu conhecer quais as características das mensagens, sejam elas do padrão construtivo ou do conteúdo, podem influenciar no comportamento do usuário. O estudo do sistema viário permitiu a escolha de vias de grande importância para a mobilidade da população para a aplicação do estudo. Os dados de tráfego e as imagens de vídeo destas vias foram utilizados na elaboração de cenários que buscaram representar situações de tráfego encontradas nos grandes centros urbanos. Os cenários foram avaliados por usuários das vias em questão. A partir dos resultados da pesquisa qualitativa, foram realizadas modelagens e obtidas equações que relacionam a percepção de fluidez do tráfego por parte dos usuários com a velocidade média do trecho. Os resultados indicaram que: (i) a velocidade média tem grande influência sobre a percepção de fluidez por parte dos motoristas; (ii) a avaliação sobre a fluidez do tráfego piora significativamente com a redução da velocidade média; (iii) os modelos para vias em estudo tem comportamentos semelhantes. Além disso, este trabalho propõe uma escala de qualificação da fluidez do tráfego levando em consideração a percepção dos usuários, utilizando a velocidade média com indicador de desempenho. / This paper proposes a method for analyzing the conditions of traffic flow on arterial roads of the Porto Alegre city from the perspective of its users in order to submit this information by variable message signs (VMS). To reach that goal has been raised: (i) state of the art and practice on the use of VMS; (ii) characteristics of the arterial roads of the city; (iii) video images and data traffic from these roads; ( iv) the perception of users about the traffic flow. The lifting of the state of the art and practice which helped identify the characteristics of messages, whether constructive or the standard of content, can influence the behavior of the user. The study of the road system allowed the choice of channels of great importance to the mobility of the population to implement the study. Traffic data and video images of these routes were used in the preparation of scenarios that sought to represent traffic situations found in large urban centers. The scenarios were evaluated by users of the roads in question. From the results of qualitative research, modeling was performed and obtained equations that relate the perception of traffic flow for users with average speed of the stretch. The results indicated that: (i) the average speed has great influence on the perception of fluidity by the drivers, (ii) the assessment of traffic flow worsened significantly with the reduction of average speed, (iii) models for railway under study have similar behaviors. In addition, this paper proposes scales qualification of traffic flow from the perspective of users, using the average speed with performance indicator.

O presente estudo parte do crescente processo de judicialização do cuidado em saúde mental de jovens usuários de drogas e tem por objetivo problematizar a forma como, na relação entre os campos da Saúde Mental e da Justiça, vai se desenvolvendo uma biopolítica voltada para o governo da população de “adolescentes drogaditos”; essa biopolítica, embora aja em nome da garantia de direitos, opera produzindo vulnerabilidades. Para essa problematização, fundamentamo-nos nas ferramentas teóricas e metodológicas da Psicologia Social, dentro de uma perspectiva pós-estruturalista, especialmente no que se refere ao pensamento de Michel Foucault, na forma como o autor desenvolveu uma análise dos discursos e da emergência dos saberes na sua articulação com mecanismos e tecnologias de poder. A partir disso, discutimos a emergência da “adolescência drogadita” como um problema social que convoca a Psicologia e o Direito a produzirem uma série de saberes e estratégias de intervenção e manejo sobre essa população, o que vai operar tanto na condução das políticas públicas quanto nos modos como esses jovens são chamados a reconhecer-se e a relacionar-se consigo. O desenvolvimento da pesquisa tem como base a análise de Processos Judiciais de adolescentes que tiveram decretada a medida protetiva de internação psiquiátrica para tratamento por drogadição. Ao analisarmos esses documentos, buscamos identificar as relações que se estabelecem entre os campos de saber e os mecanismos de poder que incidem sobre a manutenção de certas verdades ditas sobre a “adolescência drogadita”, as quais vão servir de suporte para a legitimação e atualização da estratégia de internação compulsória. A análise dos materiais adquiriu três grandes focos, quais sejam: os discursos que circunscrevem os jovens usuários de drogas enquanto sujeitos potencialmente perigosos e como uma categoria populacional de risco; os discursos em torno das famílias desses jovens que se direcionam para uma patologização e desqualificação dessas famílias, permitindo a ação interventiva do Estado; e os discursos que são associados à internação psiquiátrica, vindo a evidenciar que as justificativas para tal se voltam muito mais para a busca de estratégias punitivas do que de cuidado em saúde mental. Por fim, evidenciamos alguns dos efeitos produzidos por esses processos na vida dos jovens. / The present study addresses the increasing process of judicialization of mental health care of young drug users, and aims at problematizing the way in which a biopolitics directed towards the government of the population of ‘addicted teenagers’ has been developed in the relationship between the fields of Mental Health and Justice. Such biopolitics, in spite of guaranteeing rights, operates by producing vulnerabilities. For such problematization, we have based our study on the theoretical and methodological tools of Social Psychology, especially with regard to the work of Michel Foucault, in the way that this author developed an analysis of both discourses and the emergence of knowledges in their articulation with power mechanisms and technologies. We discuss the emergence of the socalled ‘population of young drug users’ as a social problem that calls upon the fields of Psychology and Law to produce a series of knowledges and intervention strategies to manage this population, thus operating both in the implementation of public policies and in the ways those youths are called to recognize and relate with themselves. The development of this research is based on the analysis of lawsuits of adolescents that had been ordered the protective measure of psychiatric hospitalization for treatment for drug addiction. By analyzing these documents, we have attempted to identify the relationships established between the fields of knowledge and the power mechanisms that affect the maintenance of certain truths about the so-called ‘population of young drug users’. Such truths support both the legitimation and updating of the strategy of compulsory hospitalization. The analysis of the materials has taken three major focuses: discourses that circumscribe young drug users as both potentially dangerous subjects and a risk population category; discourses about these young drug users’ families, directed to their pathologization and disqualification, allowing for State intervention; and discourses associated with psychiatric hospitalization, evidencing that justifications for its determination are much more punitive than directed to mental health care. Finally, we point out some of the effects produced by these processes in young people’s lives.

O crack é um subproduto da cocaína obtido a partir da pasta de coca acrescida do bicarbonato de sódio, sendo comercializado na forma de pequenas pedras porosas. No Brasil, o consumo de crack tem sido alvo de grande preocupação devido sua expressiva expansão em várias regiões, sendo que o aumento da prevalência do seu consumo vem sendo amplamente documentado nos últimos anos. A dependência de crack é a causa mais prevalente de internação por uso de cocaína. Há uma necessidade imediata de estudos que se direcionem para esta população. A presente pesquisa pretende demonstrar evidências capazes de contribuir para o entendimento dos mecanismos envolvidos na ação do psicotrópico crack sobre o DNA, bem como oferecer dados que auxiliem no desenvolvimento de tratamentos para pacientes usuários abusivos desta droga. Este estudo teve como objetivo avaliar o dano ao DNA e a capacidade de reparo, em 31 indivíduos usuários ativos de crack, relacionando-os com um grupo controle com 40 participantes. O trabalho foi desenvolvido através de voluntários recém internados na Clínica Marcelo Campos em São Leopoldo. Foram coletadas amostras em três momentos (internação, 48h após e ao término do tratamento) e submetidas às técnicas de micronúcleo e cometa. Dentre os resultados desta avaliação, foram evidenciados índices de dano significativamente diferentes entre os grupos nas técnicas de micronúcleos e cometa, e entre os períodos de coleta na técnica de cometa. Os valores obtidos para o índice de dano de DNA da técnica do cometa nos três momentos de avaliação revelaram uma diminuição estatisticamente significativa apenas após o término do tratamento. Em relação à utilização concomitante de outras substâncias, o consumo de tabaco ocorreu em 68% dos indivíduos, maconha em 71% e cocaína em 32%, sendo que 19% faziam uso concomitante de todas as drogas mencionadas. Houve correlação com o tempo de uso do tabaco e o índice de dano (P=0,043), MN (P=0,017) e NBP (P=0,023) em determinados momentos. O consumo de álcool ocorreu em 61,29% dos participantes, não havendo correlação estatisticamente significativa com os marcadores de dano. A idade e o tempo de utilização do crack não apresentaram associação ao índice de dano. Houve associação significativa entre o consumo de chimarrão (Ilex paraguaiensis) e MN (P= 0,045). Estudos associando o crack com dano ao DNA são, ainda, escassos. Este trabalho buscou acrescentar informações quanto ao potencial danoso desta substância. / Crack is a by-product of cocaine resulting from the addition of sodium bicarbonate to cocaine base paste, being sold in the form of small, porous rocks. In Brazil, the consumption of crack has been the subject of great concern due to its significant expansion in various regions, thus the increasing prevalence of drug use has been documented in recent years. The dependence of crack is the most prevalent cause of hospitalization due to cocaine use, supporting an immediate need for studies to target this population. This research aims to demonstrate evidence that can contribute to the understanding of the mechanisms involved in the action of psychotropic Crack on DNA, as well as provide data to assist in development of treatments for patients who are drug abusers. This study aimed to assess the damage and DNA repair capacity in 31 individuals who are active users of crack, comparing them to a control group of 40 participants. The study was conducted by volunteers newly admitted to the Clinic Marcelo Campos in São Leopoldo. Samples were collected at three time points (at admission, 48 hours latter and at the end of treatment) and subjected to the comet and micronucleus techniques. Among the results of this assessment damage indices were evident and significantly different between groups in the comet and micronucleus techniques, and between sampling periods for the comet technique. The values obtained for the rate of DNA damage in the comet technique in all three time points revealed a statistically significant decrease only after the end of treatment. Regarding the concomitant use of other substances, no significant association was found with the results. Tobacco consumption occurred in 68% of subjects, marijuana in 71% and cocaine in 32%, being 19% users of all drugs mentioned. There was a correlation over time of tobacco use and the damage index (P = 0.043), MN (P = 0.017) and NBP (P = 0.023) at certain time points.. Alcohol consumption occurred in 61.29% of the participants, there was no statistically significant correlation with markers of damage.The age and duration of use were not associated to the crack damage index. There was a significant association between the consumption of yerba mate (Ilex paraguaiensis) and MN. (P = 0.045). Studies associating the crack with DNA damage are still scarce. This study brings additional information about the potential harmful of substance.

This research aimed to investigate the uses of the written language in the Internet chat rooms and in similar virtual discourses, examining the heterogeneity, affluence and complexity of the language in those means as well as demonstrating as the traditional dichotomy between spoken and written discourse has been unmade regarding the peculiar features of these new discursive forms. The virtual chat came up trough Internet advent and its written code has revealed a new relation of the man with writing once it has brought up linguistic innovations, has detached language as a phenomenon of linguistic diversity and differences and has made linguistics to realize how theoretically irrelevant has been the acclaimed spoken/written dichotomy. For the initially described aims, this research based its theoretical perspective in the language uses, which points out language as a heterogeneous and dynamical phenomenon. / Conselho Nacional de Desenvolvimento Científico e Tecnológico / Este trabalho objetivou investigar o comportamento da língua escrita nas salas de bate-papo da Internet e em gêneros afins, tanto para mostrar a heterogeneidade, riqueza e complexidade da língua no meio, quanto para apresentar como a dicotomia oralidade/escrita encontra-se diluída dentro das especificidades e características peculiares desta nova forma discursiva. O bate-papo on-line é um gênero que emergiu com surgimento da Internet e seu código escrito acabou revelando uma nova relação do indivíduo com a forma de escrever por trazer inovações lingüísticas, privilegiar a heterogeneidade e a diversidade lingüísticas e ter mostrado a tênue fronteira entre oralidade e escrita, desconstruindo perspectivas dicotômicas sobre o assunto. Para os objetivos inicialmente descritos, este trabalho baseou-se na perspectiva dos usos lingüísticos, que aponta a língua como um fenômeno dinâmico e heterogêneo.

La gestion du risque d'inondation a évolué d'une approche structurelle à une politique nonstructurelle supportée par des outils graphiques, dont les cartes, présents à toutes les étapes de la gestion du risque d'inondation. Cependant, si elles sont parmi les meilleurs outils pour la représentation, la communication et l'aide à la décision, ces cartes se caractérisent par des lacunes dans leur figuration, notamment en raison d'une faible prise en compte de la maîtrise d'usage lors de leur conception. L'objectif principal de cette recherche est de définir les règles cartographiques spécifiques à différentes catégories d'acteurs directement usagers des cartes lors d'une phase d'évacuation (habitants, décideurs locaux et force de secours) en tenant compte de leurs caractéristiques et de leurs questions afin de produire des cartes plus efficaces pour la gestion de cette étape. Dans cette logique, l'application IMaDeS (Interactive Map Design System) a été développée pour permettre aux destinataires de co-concevoir leurs cartes dont les parangons sont évalués par oculométrie couplée à un questionnaire. / Flood risk management has evolved from a structural approach to a non-structural policy supported by graphical tools (including maps), present at all stages of the flood risk management. However, although they are among the best tools for representation, communication and decision-making, these maps are characterized by gaps in their figuration, particularly because of a weak integration of their use in the design. The main objective of this research is to define the specific mapping rules for different categories of stakeholders who are the end-users of maps during an evacuation (inhabitants, local decision-makers and rescue forces) by using their characteristics and their issues to produce more efficient maps in order to manage evacuation. Toward this goal, the IMaDeS application (Interactive Map Design System) was developed to allow stakeholders to co-build their maps and the most representative templates are evaluated by eye-tracking paired with a questionnaire.

Orientador: Cristina Maria Garcia de Lima Parada / Resumo: Os registros do uso de drogas são conhecidos nas mais diversas culturas. No Brasil, o uso de álcool e/ou outras drogas tornou-se grave problema de saúde pública. Existe estimativa de que aproximadamente 90% das mulheres usuárias de drogas estejam em idade fértil. As gestantes usuárias de álcool e/ou outras drogas enfrentam diversos obstáculos no campo social e da saúde, fazendo-se necessário o desenvolvimento de estratégias que minimizem os danos biopsicossociais relacionados, de modo que o modelo de atenção seja focado nas necessidades de saúde dessas usuárias. Ou seja, é necessário que haja um olhar voltado à integralidade e às redes de atenção à saúde, em especial nas áreas de saúde mental e materno-infantil. Este estudo é composto por três artigos: o primeiro constitui revisão integrativa da literatura e buscou identificar na produção científica dos últimos dez anos (2004-2014), evidências sobre a melhor forma de tratamento não medicamentoso para gestantes usuárias de álcool e/ou outras drogas; o segundo artigo objetivou compreender as experiências de gestantes usuárias de álcool e/ou outras drogas atendidas nos serviços públicos de saúde de Botucatu/SP, quanto à gestação e à atenção à saúde recebida e o terceiro artigo teve como objetivo compreender as experiências dos profissionais de saúde que atuam nos serviços públicos de saúde de Botucatu/SP sobre o trabalho em rede para estas gestantes. Estes dois últimos artigos foram estudos do tipo qualitativo, e adotaram como r... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Records of drug use are known in many different cultures. In Brazil the use of alcohol and other drugs has become a serious public health problem. There is estimated that approximately 90% of drug users are women of childbearing age. Pregnant women users of alcohol and other drugs face a number of obstacles in the social and health making it necessary to develop strategies to minimize the related biopsychosocial damage focusing the care model on health needs of these users. In another words, it is needed a overlook facing the completeness and health care networks particularly in the areas of mental health, maternal and child. This study consists in three items: the first is an integrative literature review and sought to identify the scientific production of the last ten years (2004-2014), evidence on the best way to non-medication treatment for pregnant women users of alcohol and/or others drugs; the second article aimed to understand the experiences of pregnant women using alcohol and/or drugs treated in the public health services in Botucatu/SP as pregnancy and the health care received; the third study aimed to understand the experiences of health professionals who works in public health services in Botucatu/SP on networking for these pregnant women. The last two items were qualitative studies and adopted as a theoretical reference the Social Representations Theory as a methodological framework and the Collective Subject Discourse. In the literature review study found that ... (Complete abstract click electronic access below) / Doutor

De nos jours, ce ne sont pas que les collections multimédias qui deviennent de plus en plus volumineuses, mais aussi les métadonnées qui les décrivent. L’extraction des métadonnées est très coûteuse en consommation de ressources. Cela pose le problème de la gestion efficace de ces grands volumes de données, en minimisant cette consommation. Le fait que les utilisateurs sont en constante interaction avec les documents multimédias et les métadonnées complique encore plus cette gestion. Dans cette thèse, nous étudions le problème de la gestion de métadonnées en intégrant les interactions des utilisateurs à deux niveaux: dans le processus de création de métadonnées et dans leur enrichissement. La grande variété de standards et normes de métadonnées existants ne sont pas interopérables. Les solutions proposées à ce problème d’interopérabilité se sont focalisées sur la création d’ontologies qui décrivent les contenus multimédias du point de vue sémantique, sans forcément prendre en compte les standards de métadonnées et d’autres informations de plus bas niveau sur les documents. Pour résoudre ce problème nous proposons un format de métadonnées qui intègre les standards et normes les plus utilisés et qui est flexible et extensible en structure et en vocabulaire. Dans le cadre d’un système de gestion des contenus multimédias, le processus d’indexation est celui qui consomme le plus de ressources, à travers les algorithmes d’indexation qui extraient les métadonnées. Dans les systèmes classiques, cette indexation est accomplie avec un ensemble d’algorithmes d’indexation figé dans le temps, sans se soucier de la consommation des ressources ni de l’évolution des besoins de l’utilisateur. Pour prendre en compte les besoins que l’utilisateur spécifie dans sa requête, afin de n’extraire que les métadonnées nécessaires et ainsi limiter d’un côté le volume de métadonnées à gérer et de l’autre la consommation des ressources, nous proposons de répartir le processus d’indexation en deux phases: une fois à l’acquisition des contenus (indexation implicite), et une deuxième fois, si besoin, au moment de l’exécution de la requête de l’utilisateur (indexation explicite) en ayant recours à une liste d’algorithmes d’indexation déterminée principalement en fonction de la requête de l’utilisateur. L’utilisateur est de plus en plus pris en compte dans les systèmes multimédias à travers ses interactions avec le système et le document. Nous proposons d’aller plus loin dans la prise en compte de l’utilisateur, en considérant ses interactions avec les différentes parties du document mais aussi avec les métadonnées qui décrivent le document. Cela a été réalisé à travers l’extension du format de métadonnées proposée, par l’ajout d une température à chaque élément du format, qui varie dans le temps, étant calculée en fonction de la façon dont l’utilisateur interagit avec le document, mais aussi avec les métadonnées dans une période de temps. Nous avons validé nos propositions dans deux domaines différents: la vidéo surveillance et le commerce électronique. Le projet LINDO nous a permis la validation du format des métadonnées et de la sélection des algorithmes d’indexation dans le cadre de l’indexation explicite, dans le cadre de la vidéo surveillance. Dans le domaine du commerce électronique, nous avons exploité les interactions des utilisateurs réels avec un site de vente en ligne pour calculer la température des métadonnées associées aux pages du site pendant une période de deux mois. Nous avons utilisé cette température pour réaliser le reclassement des résultats obtenus pour une requête de l’utilisateur. Nous avons réalisé un test utilisateur sur une vingtaine de personnes. [...] / Nowadays, not only multimedia collections become larger, but also the metadata describing them. The metadata extraction is the most ressource consumming process in the management of multimedia collections. This raises the problem of the efficient management of these large data volumes while minimizing ressource consumption. Users’ constant interactions with multimedia documents and metadata complicate this management process. In this thesis, we adress this problem of metadata management by integrating users’ interactions at two levels: in the process of metadata creation and in their enrichment. The existing metadata standards are heterogenous and not interoperable. The proposed solutions for this interoperability problem focused on creating ontologies that describe the multimedia contents from a semantic point of view, without necessarily taking into account metadata standards and other low level information. To solve this problem, we propose a metadata format that integrates the most widely used metadata standards and which is flexible and extensible in structure and vocabulary. In a multimedia management system, the indexing process is the most resource consumming, through the indexing algorithms that extract metadata. In conventional systems, the indexing is accomplished with a fixed set of indexing algorithms, without considering the resource consumption and users’ changing needs. To take into account the user’s needs, specified in his query, in ordre to extract only the necessary metadata and thus, on one side, to limit the metadata volume and on the other to reduce the resource consumption, we propose to split the indexing process into two phases: first time, at the contents acquisition time (i.e., implicit indexation), and, a second time, if necessary, at the query execution time (i.e., explicit indexation), employing a list of indexing algorithms determined mainly according to the user’s query. The users are more and more taken into account in multimedia systems through their interactions with the system and the documents. We propose to go further in this consideration, by taking into account users’interactions with different parts of the document, and also with the document’s metadata. This was achieved through the extention of the proposed metadata format, by associating a temperature to each metadata element. This temperature is calculated according to the users’ interactions with the document and with the metadata, in a time period. We have validated our proposals in two different domains: vidéosurveillance and e-commerce. The LINDO project has allowed us to validate the metadata format and indexing algorithms selection in the context of explicit indexation, for a video surceillance use case. For the e-commerce, we have used an online shopping site and the interactions of its real users, for a two months period, to calculate the temperature of the metadata associated to the web pages describing the site’s products. We have used this temperature for reranking the results obtained for a user’s query. We conducted a user study with twenty people, which shows that, for some users’ queries, the results reranking helps the users to find faster the desired information. This thesis has addressed the problem of taking into account the user in the multimedia documents management by: (1 )proposing a model metadata that integrates the most used metadata standards; (2) spliting the multimedia indexing in two steps ( implicit and explicit indexation); (3) enriching the metadata according to the users’ interactions with the system, the multimedia documents and the metadata.