A proliferação de dispositivos móveis e de redes sem fio tem encorajado um crescente interesse em sistemas e serviços baseados na localização de dispositivos portáteis, especialmente em ambientes internos, como edifícios e residências. A localização de um dispositivo portátil é um parâmetro crítico em aplicações baseadas no contexto, as quais requerem grande precisão na estimativa de localização. Entretanto, projetar e desenvolver sistemas de localização em interiores, com crescente precisão na estimação e decrescente custo de instalação, é um problema desafiador. Uma abordagem bastante interessante para satisfazer os requisitos de baixo custo consiste em utilizar as infra-estruturas existentes de redes locais sem fio (WLAN) no padrão IEEE 802.11, que já estão instaladas em muitos ambientes. A maioria das abordagens para localização usando WLAN propostas na literatura é baseada em técnicas probabilísticas, que apresentam bom desempenho e estão cada vez mais populares. Estas técnicas usam um mapa com a informação da potência recebida do sinal (RSSI) juntamente com a freqüência de presença de sinal coletada de múltiplos pontos de acesso Wi-Fi, em diferentes localizações físicas no ambiente. Porém, a informação sobre freqüência de presença de sinal pode ser muito ruidosa devido à natureza imprevisível das falhas de transmissão, as quais podem ocorrer decorrentes de diversos fatores. Este trabalho propõe um novo sistema de localização Wi-Fi, o WBLS (Wireless Based Location System), que não considera a informação sobre freqüência de presença de sinal no processo de estimação, visando eliminar os ruídos a ela associados. O WBLS explora o fato da potência do sinal Wi-Fi variar com a localização e usa um HMM descrito em um grafo onde os nós representam as localizações e as arestas, as probabilidades de transição em função da topologia do ambiente e das velocidades esperadas de um pedestre portando um dispositivo móvel. Investiga-se em que situações a eliminação da informação sobre freqüência de presença de sinal devido a seus ruídos associados aumenta a exatidão da estimativa de localização, apesar do descarte da informação em si. Os experimentos realizados demonstram que a característica mais importante do WBLS é uma particular robustez ao lidar com desligamentos de pontos de acesso, os quais podem ocorrer sem nenhum aviso ou previsão em um ambiente onde pouco controle se tem sobre sua infra-estrutura. / The proliferation of mobile computing devices and wireless networks has fostered a growing interest in location-based systems and services for Portable Wireless Devices, specially in indoor environments. The location of a handheld device is a critical parameter in context-aware applications, which require high degree of accuracy of location estimation. However, designing and developing indoor location systems with increasing estimation accuracy and decreasing cost installation is a challenging problem. A very interesting approach to reach low-cost requirements consists in using the pre-existing IEEE 802.11 wireless local area network (WLAN) infrastructure that is already installed in many places. Most of the WLAN indoor location approaches proposed in the literature are based on probabilistic techniques which show good performance and are becoming increasingly popular. Such approaches use a map of received signal strength information and signal presence frequency collected from multiple Wi-Fi access points at different physical locations in the environment. However, the signal presence frequency information can be very noisy due to the unpredictable nature of transmissions failures, which can be caused by several factors. This work proposes a new probabilistic-based Wi-Fi location system, WBLS (Wireless Based Location System), which doesn\'t take the signal presence frequency information into account in the estimation process, in an attempt to eliminate its associated noise. WBLS exploits the fact that Wi-Fi signal strength vary with location, and uses an HMM on a graph of location nodes whose transition probabilities are a function of the building\'s floor plan and expected speeds of a pedestrian holding a portable device. We investigate if eliminating signal presence frequency information due to its associated noise increases the accuracy of the location estimation, despite the amount of information about the signal presence that is discarded. Experiments show that the most important feature of WBLS is a particular robustness while dealing with access points shutdowns that may happen without any warning in an environment where there is little control over the infrastructure.

Dentro da área de Ensino de Ciências é possível identificar a existência da linha de trabalho que advoga o ensino de uma Física detentora de valor Cultural dentro de sala de aula. Trabalhos como os de Zanetic (1989) sugerem que a Física, por não ser desprovida de conteúdo ideológico e político seja ensinada nas escolas públicas dentro de um contexto sociocultural. Neste caminho, pretendemos contribuir para o diálogo entre a Física e a Cultura, em especial a Cultura de Massas, apresentando uma análise do potencial didático apresentado pela Leitura de Histórias em Quadrinhos de Ficção Científica dentro da sala de aula em um curso de Física. Utilizamos como referenciais para a relação entre Física e Cultura os trabalhos de George Snyders (1988) C.P. Snow (1959) e do próprio Zanetic (1989). A relação entre História em Quadrinhos e Educação foi analisada a partir dos trabalhos do prof. Waldomiro Vergueiro (2009) da ECA-USP e de outros estudiosos da área. Para iluminar o laço entre a Ficção Científica e o Ensino de Física, nos baseamos na teoria de análise dos pólos temáticos desenvolvida por Piassi (2007). Como demonstraremos adiante, o diálogo entre a Física, as Histórias em Quadrinhos de Ficção Científica e o período histórico-social que as produz é profundo, fazendo com que a leitura deste material em sala de aula possa fornecer o ponto de partida para o estudo de uma Física detentora de um perfil cultural, cujo domínio é capaz de levar o aluno ao questionamento, resultando em uma ação de mudança social. O recorte temático para estudo adotou as histórias do título em quadrinhos \"Quarteto Fantástico\", publicado originalmente desde 1962 e cujo lançamento pode ser considerado uma resposta cultural as sucessivas derrotas enfrentadas pela sociedade norte-americana no campo da corrida espacial. Exploraremos o panorama geral delineado pelos três números iniciais da publicação, responsáveis pela definição de uma matriz narrativa publicada de forma ininterrupta até os dias de hoje. Para fins de comparação adotamos as três primeiras aventuras de sua versão reformulada para o Século XXI após os eventos de 11 de Setembro de 2001, o chamado \"Quarteto Fantástico Ultimate\". Nosso objetivo é apresentar as relações entre a expressão artística da Ciência e os anseios sociais relacionados às descobertas científicas, apresentadas nos dois títulos. O resultado obtido evidencia que discutir uma História em Quadrinhos de Ficção Científica em sala de aula significa discutir a sociedade que as criou, fazendo com que a leitura crítica de um título possibilite ao aluno o contato com uma Física fruto da construção humana e detentora de um papel cultural. / Within the area of Science Education it is possible to identify a line of work where several studies advocate the teaching of a Cultural Physics in the classroom. Authors such as Zanetic (1989) suggests that physics can be taught in public schools within a sociocultural context, because it is not devoid of ideological and political content. In this way, we intend to contribute to the dialogue between physics and culture, especially the mass culture, presenting an analysis of the didactic potential represented by reading Sci Fi comics during physics class. We used works such as George Snyders (1988) C.P. Snow (1959) and the very own Zanetic (1989) as references for the relationship between physics and culture. The relationship between Comics and Education was analyzed based on the studies of prof. Waldomiro Vergueiro (2009), ECA-USP and other scholars in the field. To illuminate the link between science fiction and physics teaching, we rely on the theory developed by Piassi (2007) for exploration of thematic poles. As we intend to demonstrate further, the dialogue between physics, sci fi comics and the socialhistorical period which produces it is deep, making the reading material in the classroom provide a starting point for the studies of physics with a cultural profile. This domain leads to questioning the student, which may result in an action for social change. The cutout theme adopted for the stories study is the comic book title \"Fantastic Four\", originally published in 1962 and whose release can be considered as a cultural response to the successive defeats faced by the American society throughout the space race, as will be demonstrated below. We explore the big picture outlined by the first three numbers of the publication, responsible for the definition of a matrix narrative published uninterruptedly up until the present day. For comparison purposes we will adopt the first three adventures of a reformulated version for the twenty-first century after the events of September 11, 2001, called \"Ultimate Fantastic Four\". Our goal is to demonstrate the relationship between expressive artistic science and social expectations related scientific findings, presented in both titles. As a result, we expect to demonstrate that discussing a sci fi comic book in the classroom means discussing the society that created them, making the critical reading of a title possible for the students to make contact with detaining physics that hold a cultural result of the human construction.

This thesis is a science fiction exploration of a future dystopian world where privacy becomes a dominant currency that is distributed according to social class and ranking mechanisms. It utilizes speculative world-building to study the unanticipated implications of technology on personal privacy, surveillance and social inequality on future societies. The project introduces The Mall, as a highly efficient and hyper-connected world, but also exposes its downfall as a society with heightened cultural and socio-political disparities. Inspired by past civilizations, the development of the modern nation-state as well as contemporary society, the design adapts, appropriates and reformulates existing cultures into new hybrid possibilities. This thesis project is presented as an illustrated coded tapestry that allows the viewer to explore and interact with various components of the narrative to speculate and critique an alternative future-world void of privacy.

Les Technologies d'Information et de Communication (TIC) facilitent la collecte et le traitement d'informations numériques, aussi nombreuses que variées, et sont de plus en plus sollicitées dans différents domaines (géographie, informatique, économie, statistiques etc.). La thèse a pour objectif de montrer les apports des TIC dans l'étude d'objets ou phénomènes géographiques dont la distribution est variable dans l'espace. Dans un premier temps, des inégalités territoriales de diffusion d'infrastructures Internet sont observées à différentes échelles, ce qui est communément appelé " la fracture numérique ". Pour remédier à ces inégalités, en particulier dans des espaces peu densément peuplés, la solution proposée est d'envisager une desserte maximale du territoire par la technologie non-filaire (Wi-Fi). Cette solution a été appliquée pour une commune drômoise (La Roche-sur-le-Buis). Les données (bâti) sont de type images et nécessitent un dispositif de repérage et de collecte approprié qui fait l'objet du second temps de la recherche. L'objectif a été de trouver une méthode relativement simple et accessible d'extraction de données du bâti sous un logiciel de géo-localisation en accès libre (type Google Earth). Ce logiciel permet d'accéder à des bases de données d'images raster grand public couvrant le monde entier. A une échelle fine, les méthodes habituelles de télédétection n'étant pas assez satisfaisantes, une autre méthode basée sur une stratégie de choix de la cible, de l'image (bonne résolution spatiale) et de la méthode de détection de l'objet spatial (bâti) à l'aide d'un Système d'Information Géographique (SIG) est proposée en mode vecteur. Elle est testée en France et en Syrie à différentes échelles. Les résultats montrent que la qualité de cette approche semi-automatique, voire automatique, est liée à certains paramètres dans les trois phases de la méthode : phase de choix des données, phase de traitement et phase d'analyse

Avec l'arrivée des systèmes radio mobiles de troisième et de quatrième génération, les standards de communications ont tendance à occuper plus de bande pour pouvoir assurer des services de voix, de données et de multimédia. En parallèle, le terminal mobile doit être reconfigurable pour couvrir à la fois le service cellulaire et la connectivité de données. Dans ce contexte, la tendance est d'intégrer les fonctions radio et bandes de base sur le même substrat en utilisant la technologie CMOS afin de réduire la surface, le coût de fabrication et la consommation des terminaux sans fils. Récemment, de nouvelles architectures de réception radio dites " échantillonnées " sont apparues (TexasInstruments, STMicroelectronics, UCLA). Dans ce cas, l'échantillonnage est fait directement sur le signal RF et la majorité du traitement de signal se fait en temps-discret par des capacités commutées. L'évolution de la technologie CMOS et la miniaturisation des transistors rendent la conception analogique de plus en plus difficile (capacités parasites, bruit, linéarité, etc.). De nouveaux effets parasites apparaissent comme la fuite de grille qui inquiète désormais les technologues et les concepteurs de circuits. D'un autre côté, des contraintes de dynamique surgissent avec la diminution des tensions d'alimentation et le bruit des circuits numériques de plus en plus denses augmente considérablement. Le but de ce travail de thèse est de répondre à la question de la portabilité de la solution échantillonnée, en étudiant l'impact des différents effets parasites cités précédemment sur les performances radio de la solution. Ainsi, les critères de portabilité qui sont considérés sont la reconfigurabilité, l'immunité aux effets parasites, l'adaptation à la baisse des tensions d'alimentation, la surface, la consommation et la facilité de conception. Ce travail de thèse a été basé sur des études théoriques et sur des simulations d'une solution échantillonnée de réception radio. Afin d'affronter réellement les problématiques de portabilité, un portage d'une chaîne de réception échantillonnée Wi-Fi/WiMAX de CMOS 65nm à 45nm a été réalisé. Les résultats de mesures obtenus sur ce circuit donnent une grande confiance vis-à-vis des performances radio de la solution échantillonnée et constituent un premier élément de réponse concret à la question de portabilité étudiée.

Ce mémoire de thèse porte sur la conception, la validation et l'application du codage canal en mode relais dans le cadre de système WiFi. A cette fin, le modèle de transmission coopératif est introduit dans le chapitre 1 et le chapitre 2 se consacre à l'étude du décodeur MIMO intégré dans le système coopératif. Le chapitre 3 se consacre à l'étude du protocole baptisé Relais-SISO et sa mise en œuvre dans le standard IEEE802.11a à 5 GHz. De nouvelles structures de trame sont proposées en ajoutant des préambules destinés à être exploités par le mode coopératif. Des résultats de simulation démontrent l'avantage de la technique coopérative. A notre connaissance, ces travaux sont les premiers à proposer une application du codage relais au WiFi. Le chapitre 4, une stratégie hybride basée sur la solution Relais-SISO est présentée car elle améliore les performances du système Relais-SISO. Le mode hybride proposé s'appuie sur l'évaluation de la qualité du lien coopératif pour activer ce mode. Dans le chapitre 5, l'optimisation du mode coopératif de la couche physique est réalisé en mettant en œuvre la chaîne de partitionnement du Golden Code. On met en évidence le fait qu'une simple combinaison de ce dernier et d'un code convolutif, fournit un gain de codage grâce au gain du déterminant du Golden code. Le travail serait incomplet sans tenir compte du nouveau standard WiFi IEEE802.11n ratifié en Octobre 2009. C'est l'objet du chapitre 6, qui propose un protocole coopératif, baptisé Relay-MIMO, qui exploite d'une manière conjointe la diversité MIMO et la diversité de coopération.

In mobile computing systems, predicting the next location of a mobile wireless user has gained interest over the past decade. Location prediction may have a wide-range of application areas such as network load balancing, advertising and web page prefetching. In the literature, there exist many location predictors which are divided into two main classes: domain-independent and domain-specific. Song et al. compare the prediction accuracy of the domain-independent predictors from four major families, namely, Markov-based, compression-based, PPM and SPM predictors on Dartmouth&#039 / s campus-wide Wi-Fi mobility data. As a result, the low-order Markov predictors are found as the best predictor. In another work, Bayir et al. propose a domain-specific location predictor (LPMP) as the application of a framework used for discovering mobile cell phone user profiles. In this thesis, we evaluate LPMP and the best Markov predictor with Dartmouth&#039 / s campus-wide Wi-Fi mobility data in terms of accuracy. We also propose a simple method which improves the accuracy of LPMP slightly in the location prediction part of LPMP. Our results show that the accuracy of the best Markov predictor is better than that of LPMP in total. However, interestingly, LPMP yields more accurate results than the best Markov predictor does for the users with the low prediction accuracy.

<p>The color gamut, i.e. the range of reproducible colors, is in most conventional display systems not sufficient for accurate color reproduction of highly saturated colors. Any conventional three-primary display suffers from a color gamut limited within the triangle spanned by the primary colors. Even by using purer primaries, enlarging the triangle, there will still be a problem to cover all the perceivable colors. By using a system with more than three primary colors, in printing denoted Hi-Fi color, the gamut will be expanded into a polygon, yielding a larger gamut and better color reproduction. </p><p><i>Digital Light Processing (DLP)</i> is a projection technology developed by Texas Instrument. It uses a chip with an array of thousands of individually controllable micromirrors, each representing a single pixel in the projected image. A lamp illuminates the micromirrors, and by controlling the amount of time each mirror reflect the light, using pulse width modulation, the projected image is created. Color reproduction is achieved by letting the light pass through color filters, corresponding to the three primaries, mounted in a filter wheel. </p><p>In this diploma work, the DLP projector InFocus^® LP™350 has been evaluated, using the Photo Research^® PR^®-705 Spectroradiometer. The colorimetric performance of the projector is found to be surprisingly poor, with a color gamut noticeably smaller then that of a CRT monitor using standardized phosphors. This is due to the broad banded filters used, yielding increased brightness at the expense of the pureness of the primaries. </p><p>With the intention of evaluating the potential for the DLP technology in multi- primary systems, color filters are selected for additional primary colors. The filters are selected from a set of commercially available filters, the Kodak Wratten filters for science and technology. Used as performance criteria for filter selection is the volume of the gamut in the CIE 1976 (L*u*v*) uniform color space. </p><p>The selected filters are measured and evaluated in combination with the projector, verifying the theoretical results from the filter selection process. Colorimetric performance of the system is greatly improved, yielding an expansion of the color gamut in CIE 1976 (L*u*v*) color space by 79%, relative the original three-primary system. These results indicate the potential for DLP in multiprimary display systems, with the capacity to greatly expand the color gamut, by using carefully selected filters for additional primary colors.</p>

In this thesis, I will examine the connected representations of religion and gender in the context of contemporary American telefantasy (a term for science fiction, fantasy, and horror television genres) programs that include characters who experience fantastic visions that can be explained as originating from either divine or medically materialist origins. The fantastic mode, facilitated by telefantasy’s non-verisimilitudinous genre, presents these visions in a liminal space in which religious and gender representations can potentially subvert or challenge patriarchal and hegemonic representational norms. I analyze Battlestar Galactica (Sci-Fi 2003-2009), Eli Stone (ABC 2008-2009), and Wonderfalls (FOX 2004) for their formal presentation of visions, representations of visionary characters, and the religious representations that form the context for the visions and visionaries. I focus on visionary characters that are directly implicated by the television text as being potential prophets: Laura Roslin and Gaius Baltar on Battlestar Galactica, Eli Stone on Eli Stone, and Jaye Tyler on Wonderfalls. Though each visionary character explores the possibility of subverting patriarchal religious norms, Roslin, Baltar, and Stone’s prophetic roles ultimately privilege patriarchal readings of their narratives, but Jaye, by avoiding the language-symbol systems of traditional religions, maintains the fantastic liminal space and thus the potential for subversion, even if it is only a possibility in the narrative. This thesis seeks to contribute to the scholarship of religious representations in fictional television, with a special emphasis on telefantasy. / text

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