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Toulikas, Dimitrios. "De Sitter Vacua and Black Hole Microstates in String Theory." Electronic Thesis or Diss., université Paris-Saclay, 2024. http://www.theses.fr/2024UPASP177.
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Depuis la découverte que l'expansion de notre univers est probablement entraînée par l'énergie du vide, la recherche de vides de Sitter en quatre dimensions dans la théorie des cordes est devenue un des principaux objectifs de la phénoménologie des cordes. Cependant, malgré deux décennies d'efforts, la construction de vides de Sitter métastables reste un grand défi, et la construction vieille de vingt ans de Kachru, Kallosh, Linde et Trivedi (KKLT), bien que controversée, demeure un des exemples prototypes. Le scénario KKLT est une construction en deux étapes, où, dans un premier temps, la théorie des champs effective en quatre dimensions est utilisée pour obtenir un vide AdS4 supersymétrique, puis des anti-branes D3 sont ajoutées pour briser la supersymétrie et relever l'énergie du vide à une valeur positive. Dans la première partie de cette thèse, nous étudions en détail certains aspects des deux étapes de cette proposition. D'une part, nous fournissons une description en dix dimensions des vides AdS4 intermédiaires en utilisant le langage de la géométrie complexe généralisée. D'autre part, nous étudions la rétroaction des anti-branes D3 et découvrons qu'elles génèrent aussi des flux de trois-forme. Nous répertorions toutes les composantes de ce flux, calculons leur effet sur les D7-branes enroulées autour des cycles de quatre dimensions dans la variété de compactification, et élaborons un scénario de type KKLT plus minimaliste. Dans la deuxième partie de la thèse, nous travaillons sur la nature de la microstructure des trous noirs, un autre problème important que la théorie des cordes devrait résoudre. En relativité générale, les trous noirs sont caractérisés de manière unique par peu de paramètres asymptotiques. Cependant, les trous noirs possèdent aussi une énorme entropie S, qui devrait être expliquée par une description microscopique. Nous examinons cette divergence numérique à travers le prisme de la proposition des fuzzballs, qui affirme qu'il existe e^S solutions sans horizon qui ressemblent au trou noir de loin, mais diffèrent à proximité de l'horizon. Plus précisément, nous travaillons dans le cadre du programme des géométries de microétats, qui concerne les fuzzballs décrits comme des solutions sans horizon en supergravité. Nous étudions le trou noir M2-M5-P, dont l'entropie à faible couplage provient du fractionnement de chaque brane M2 en bandes reliant des branes M5 parallèles. La rétroaction de telles bandes M2 est similaire à un pic de Callan-Maldacena, et pour plusieurs branes M5 et M2, on obtient une structure complexe en forme de labyrinthe à laquelle on peut ajouter des ondes de quantité de mouvement. Globalement, ce «super-maze» préserve quatre supercharges, mais localement, ce nombre est porté à seize. Inspirés par ce résultat, nous montrons que toutes les géométries de microétats connues sont basées sur des «themelia», des configurations de branes présentant cet accroissement local de supersymétrie. Nous expliquons pourquoi les solutions de supergravité rétroagies correspondant aux themelia devraient être lisses et sans horizon, et discutons des progrès récents dans la construction des solutions de supergravité du super-maze. Nous montrons que les solutions de supergravité pour les systèmes d'intersection 1/4-BPS de branes M2 et M5 sont entièrement caractérisées par une fonction unique satisfaisant une équation non linéaire de type Monge-Ampère, et démontrons que, pour toute solution 1/4-BPS M2-M5, l'ajout de quantité de mouvement pour arriver à une solution 1/8-BPS est régi par un système d'équations linéaires. Enfin, comme première étape vers la construction de solutions explicites, nous examinons une limite proche des branes de certaines intersections simples M2-M5, où les équations BPS se linéarisent et l'on obtient des géométries de la forme AdS3×S3×S3×Σ, avec Σ une surface de RiemannSince the discovery that the expansion of our universe is most likely driven by vacuum energy, finding four-dimensional de Sitter vacua in String Theory has been one of the main goals of String Phenomenology. However, despite two decades of efforts, constructing metastable de Sitter vacua continues to be a great challenge, and the twenty-year-old construction of Kachru, Kallosh, Linde and Trivedi (KKLT), although not uncontested, remains one of the prototypical examples. The KKLT scenario is a two-step construction, where initially four-dimensional effective field theory is used to obtain a supersymmetric AdS4 vacuum, and then anti-D3 branes are added to break supersymmetry and uplift the vacuum energy to a positive value. In the first part of this thesis, we study in detail some aspects of both steps of this proposal. On the one hand, we provide a ten-dimensional description of the intermediate AdS4 vacua using the language of Generalized Complex Geometry. On the other hand, we study the backreaction of the anti-D3 branes and find that they also source three-form fluxes. We tabulate all components of this flux, calculate their effect on the D7-branes wrapping four-cycles in the bulk of the compactification manifold, and devise a more minimalist KKLT-like scenario. In the second part of the thesis, we work on the nature of the microstructure of black holes, which is another important issue that String Theory should be able to address. In General Relativity, black holes are uniquely characterized by very few asymptotic parameters. However, black holes also have a huge entropy S, which should be explained by a microscopic description. We look at this numerical discrepancy through the lens of the fuzzball proposal, which claims that there are e^S horizonless solutions that resemble the black hole from afar but differ from it in the vicinity of the horizon. More precisely, we work in the context of the microstate geometries programme, which concerns fuzzballs that can be described as horizonless solutions in supergravity. We study the M2-M5-P black-hole, whose entropy at weak coupling comes from the fractionation of each M2-brane into strips connecting parallel M5-branes. The backreaction of such M2-strips is similar to a Callan-Maldacena spike, and for multiple M5- and M2-branes, one gets a complicated maze-like structure to which one can add momentum waves. Globally, this “super-maze” preserves four supercharges, but locally this number is enhanced to sixteen. Inspired by this result, we show that all known microstate geometries are based on “themelia”, which are brane configurations that exhibit this local supersymmetry enhancement. We explain why the fully back-reacted supergravity solutions corresponding to themelia should be smooth and horizonless, and then discuss recent progress in constructing the supergravity solutions corresponding to the super-maze. We show that the supergravity solutions for 1/4-BPS intersecting systems of M2- and M5-branes are completely characterized by a single function that satisfies a non-linear Monge-Ampère-like equation, and we demonstrate that given any M2-M5 1/4-BPS solution, the addition of momentum to arrive at an 1/8-BPS solution is governed by a linear system of equations. Finally, as a first step towards constructing explicit solutions, we look at a near-brane limit of certain single M2-M5 intersections, where the BPS equations linearize and one gets geometries of the form AdS3×S3×S3×Σ, with Σ a Riemann surface
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Baker, Michelle Mary. "Policing Publications: Sites of Censorship Classification Enforcement in New Zealand." Thesis, University of Canterbury. Sociology and Anthropology, 2006. http://hdl.handle.net/10092/916.
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This thesis focuses on the work of policing, regulating and monitoring of New Zealand public censorship classifications. It follows the processes and agents involved in the day-to-day practices of the enforcement of the classifications given to objects by the Office of Film and Literature Classification. Responsibility for the enforcement of the classification decisions of the Office is delegated to private agents and agencies involved in supplying audiences with classified media products - cinemas, video stores, bookstores and libraries. The thesis also documents enforcement undertaken directly by public agents of the Censorship Compliance Unit. In this case enforcement is concerned with unclassified publications circulating on the Internet. The thesis argues that the networks of agents assembled for the practices of enforcement evolve as the forms of media evolve or change. The thesis focuses on the modes of interaction between agents, media and publics enacted in the different sites of the cinema, the bookstore, the video store, the library and the Internet. It documents the work of enforcement involved in the purchase of images for a fixed period of time in the fixed site of the cinema; the purchase of books from the fixed site of the bookstore; the hire of video films and video games from the fixed site of the video store; and the borrowing of books and videos from the fixed site of the public library. It contrasts the work of enforcement in these different sites with the development of new work practices involved in the interactive, fluid and seemingly intangible yet still policed site of the Internet. It documents how the responsibilities for, and the practices of, enforcement shift between public sites of enforcement to the increasingly difficult public monitoring of the private consumption of images distributed through the media of the Internet. It pays attention to how different methods and strategies of enforcement have been developed in response to both the classification and consumption of the expanding variety of mobile media and the proliferation and consumption of images in the unclassified and fluid world of the Internet.
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Dodds, Sherril. "Video dance : hybrid sites and fluid bodies." Thesis, University of Surrey, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.363799.
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Chhina, Gagun S. "Video gaming parlours : the emergence of video gaming in India." Thesis, University of Manchester, 2016. https://www.research.manchester.ac.uk/portal/en/theses/video-gaming-parlours-the-emergence-of-video-gaming-in-india(75217f0f-c060-4c68-b708-ed496b3988e1).html.
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This thesis critically interrogates the role of local context in the adoption and interpretation of video technology and gaming practices in the little studied locale of India. Video gaming is a recent phenomenon in India which has been rapidly increasing in popularity, yet it has gained little academic attention in digital gaming research. The project seeks to understand the emergence of practices of consumption of video games in India from the point of view of Indians themselves through the exploration of how Indian video gamers situate, interpret and negotiate the practice of video game play. In his book Video Gamers (2012), Gary Crawford makes a case for analysing game play as a practice, situated within everyday experiences and social networks. Crawford identifies two deficiencies in gaming studies: the dominance of a Western-centric viewpoint and the disregard for player context. This research addresses these shortcomings in two ways. First, through situating the field research in Chandigarh. Second, by employing a mixed methods qualitative approach - observations, interviews, focus groups, field notes, pictures and video recordings – to elicit the detail of the gamers' cultural context. Situating these practices within the broader social, historical, geographical and cultural milieu allows for the conceptualisation of contextual factors in terms of their influence on the adoption and interpretation of the global gaming practice in a local setting. These methods allow for the examination of, first, multiple culturally embedded factors and, second, the players' processes of sense making applied to video gaming. Each method makes the social world of the gamers visible in different ways. Fieldwork predominantly took place in video gaming parlours. Investigating game players in the space of the video gaming parlour enabled a more honed understanding of how the practice of video gaming was ‘glocalised’ within particular social, geographical and cultural contexts. A smaller second study was conducted in Manchester, to collect data in a setting that is culturally different from India. This contrasting data provided greater sensitivity to cultural factors in India which might have otherwise been overlooked or which had been obscured. The research draws theoretically upon Bourdieu’s theories of social field, habitus, and capital, combining these with Goffman’s notions of dramaturgy and framing, and Robertson’s concept of glocalisation. These concepts provided a theoretical framework that enabled a interrogation of the data to reveal the sociocultural processes embedded in the gaming parlours, and the individual’s creative engagements with video game products themselves. The methodological and theoretical framework, then, were complementary, offering both an experiential and contextual approach. This study found that video gamers interpret and make sense of the practice of video gaming through their contextual situation, and that they will both consciously and unconsciously attempt to glocalise the practice of video gaming so that it becomes culturally more acceptable.
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Ferreira, Vitor Paulo de Sousa. "O uso do video nos sites dos jornais impressos." Master's thesis, Faculdade de Ciências Sociais e Humanas, Universidade Nova de Lisboa, 2011. http://hdl.handle.net/10362/10568.
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DISSERTAÇÃO APRESENTADA PARA CUMPRIMENTO DOS REQUISITOS NECESSÁRIOS À OBTENÇÃO DO
GRAU DE MESTRE EM (CIÊNCIAS DA COMUNICAÇÃO, VERTENTE DE CINEMA E TELEVISÃO),Quando a Internet apareceu para imprimir mudanças decisivas nas nossas vidas, o Vídeo já havia conquistado um lugar de sólida importância na esfera da Comunicação. O próprio Vídeo, quando surgiu, operou um verdadeiro impacto não apenas na forma como comunicamos, mas no modo como vivemos e vivenciamos as artes, as ciências, as notícias do quotidiano, os temas e os assuntos da actualidade, a relação com as pessoas e as obras humanas, e muito mais. Apesar de ter tido uma primeira aparição algo discreta, a Internet veio para ficar e revolucionou quase todas as formas de comunicação. Subitamente, entrou na nossa vida e alterou a forma de estarmos no mundo e de nos relacionarmos com este, essencialmente porque através da Internet se quebram as barreiras de tempo e lugar. À medida que transfigura a Comunicação, a Internet causa inevitavelmente os seus efeitos nos Mass Media, ou na Comunicação de Massas. Os Mass Media – a Televisão, a Rádio, os Jornais ou as Revistas… – tal como os conhecíamos, são agora conhecidos como os "meios de comunicação tradicionais" face aos "novos media" que, então, despontaram. É impossível ignorar o fenómeno da Internet. Ora, todas estas mudanças se vão reflectir – e muito – no Jornalismo. Nos dias de hoje, com vista a não defraudar as expectativas de audiências cada vez mais exigentes, Jornalistas de todo o mundo se sentem persuadidos a actualizar a metodologia de "fazer" notícias. Novas formas de Jornalismo emergem e conquistam lugares cativos, particularmente o Jornalismo Online. Pela primeira vez estes tipos de Jornalismo não só possibilitam, como convidam o leitor para assumir um papel activo e participar, pela primeira vez, nos processos de produção. Estas novas audiências partilham pensamentos, impressões, sentimentos. Elas contribuem com as suas perspectivas, ideias e opiniões. O objectivo central deste estudo é observar, então, a presença do vídeo online em alguns dos sites de Jornais Impressos Portugueses. Esta dissertação procura oferecer, numa óptica descritiva, o panorama destas mudanças e actuais possibilidades do Jornalismo, focando, em especial, o Jornalismo Online que se apoia em documentos de Vídeo e os seus efeitos na audiência.
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Kibby, Helen R. "Higher Sites 101." Virtual Press, 2006. http://liblink.bsu.edu/uhtbin/catkey/1337199.
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Higher Sites has been designed as a fully functioning business. The appendix of this creative project paper includes Higher Sites' full business plan. The business plan includes projected revenue and profit for the next three years.Higher Sites 101 is a two-part DVD set designed to familiarize new Higher Sites employees with the company. Disc I explains the services that Higher Sites offers to adoptive parents. It also walks the viewer through the process of creating adoption videos using the Higher Sites method. Example videos are included. Disc II is a data DVD that includes full-screen QuickTime movies. The movies demonstrate to the viewer how to perform specific tasks in Final Cut Pro, iDVD and DVD Studio Pro. It is necessary for the viewer to watch these QuickTime movies on a monitor that is 21 inches or larger.Department of Telecommunications
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Miloudi, Benchaâ. "Modélisation d’écoulements de gaz raréfiés en vue de l’étude des fuites internes dans les machines volumétriques produisant des vides moyens." Valenciennes, 1994. https://ged.uphf.fr/nuxeo/site/esupversions/a557e18f-4212-4cfe-b66c-5e10a68b4a1c.
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Les fuites internes jouent un rôle très important sur les performances des machines volumétriques, en particulier sur le débit réel à l'aspiration et le vide limite qu'il est possible d'atteindre. Pour les pompes volumétriques travaillant dans le vide grossier, les écoulements de fuites internes peuvent être convenablement décrits par un modèle de fluide visqueux. En revanche, dans le vide poussé, les écoulements de fuites internes doivent être décrits dans le cadre de la théorie cinétique des gaz. Entre ces deux régimes extrêmes d’écoulement, on a affaire au régime intermédiaire pour lequel il n'existe pas de formulation simple. Le but de notre travail est de dégager des modèles d’écoulement simples et réalistes, représentant les trois régimes susceptibles d’être rencontrés dans les machines volumétriques produisant des vides moyens. On trouve dans ce mémoire, la description de deux modèles semi-empiriques et celle d'une étude expérimentale. Cette dernière est conçue pour valider les modèles précédents. Elle fait intervenir des écoulements intermédiaires dans des jeux annulaires de dimensions équivalentes à celles des jeux de fuites dans les pompes à vide.
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Zhang, Yi. "Heteroglossic Chinese Online Literacy Practices On Micro-Blogging and Video-Sharing Sites." Scholar Commons, 2017. http://scholarcommons.usf.edu/etd/6788.
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This study investigates Chinese online users’ adoptions of various languages and other meaning making signs in their online literacy practices in two popular Chinese CMC sites, Weibo (micro-blogging) and bilibili.com (video-sharing). Adopting the theoretical framework of heteroglossia (Bakhtin, 1981), I explore how various meaning making resources are creatively and playfully utilized by Chinese users in their online communication. After two-month data collection, I sampled the non-standard literacy practices (e.g., foreign language transliteration) identified from micro-blogging postings and comments in Weibo, as well as spontaneous (known as “bullet curtain” comments) and traditional text-box comments from featured videos in bilibili.com. The findings resulted in 30,005 non-standard literacy practice types which contain meaning making features from languages (e.g., stylized Chinese Mandarin) and other meaning making signs (e.g., emojis) from both sites. The analysis suggests that Chinese online communication are noticeably hybrid with plurillingual and non-linguistic semiotic resources. These practices reflect the Bakhtinian notion of heteroglossic communication in which people stylize their language use with various meaning making resources. In addition, many practices are also “carnivalesque” (Bakhtin, 1984) which is characterized with creativity and playfulness. The study further deconstructs the notion of multilingualism and extends the discussion of how online communication opens up space for non-conventional and creative literacy practices, which potentially challenge the authoritative policies and voices.
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Cucinotta, Tom. "See/think/share : an online classroom video forum /." Related website, 2008. http://www.seethinkshare.org.
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Goudemand, Charlène. "Amélioration des transmissions video MPEG-2 sur lignes ADSL basée sur une optimisation conjointe source-canal de la qualité video." Valenciennes, 2005. http://ged.univ-valenciennes.fr/nuxeo/site/esupversions/f2cfe3d4-8901-4489-b8a0-a36d41bd21d4.
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L'accès aux services multimédias est aujourd'hui possible pour les particuliers grâce aux technologies ADSL qui permettent des transmissions de données haut débit via les lignes téléphoniques. Cependant, la réception de vidéo n'est accessible qu'aux abonnés ayant une bonne qualité de ligne. Nous présentons dans le cadre de cette thèse un système original d'optimisation de la qualité vidéo transmise sur ligne ADSL dans le but d'élargir la zone de couverture de télédiffusion sur ADSL déjà existante. Le système s'appuie sur une optimisation conjointe source/canal. En effet, le codage source consiste à transcoder de façon hiérarchique le flux vidéo MPEG-2 en Data Partitioning tout en adaptant à la volée le débit vidéo en fonction de la qualité de la ligne d'abonné. Les débits optimaux de transcodage sont déterminés automatiquement selon les caractéristiques de la ligne en minimisant les dégradations visuelles de la vidéo. Pour cela, une nouvelle métrique de mesure de qualité vidéo MPEG-2 de type EQM pondérée simple à mettre en œuvre est proposée. Du côté codage canal, une étude complète d'optimisation de la transmission birésolution sur un canal DMT présente la comparaison de deux schémas de transmission hiérarchique : le schéma utilisant le multiplexage en fréquence et le schéma permettant la transmission simultanée des deux flux sur les mêmes sous-canaux grâce à l'utilisation de QAM hiérarchiques. Cette étude aboutit à la proposition de deux nouveaux algorithmes d'allocation des bits et des puissances pour les deux schémas de transmission. Finalement, l'analyse du système et les résultats de simulation mettent en évidence la supériorité de la solution proposée vis-à-vis d'une transmission monorésolution classiqueToday, multimedia services have become accessible for private individuals thanks to ADSL technologies that uses existing phone lines to transmit data at high bit rates. However, video broadcasting over ADSL is only accessible to subscribers with good quality lines. We present an original system that optimizes the video quality over ADSL lines. The aim of the proposed system is to increase the reach of video broadcasting solutions over ADSL that already exists. The system is based on a joint source/channel optimization: source coding is based on a MPEG-2 scalable transcoding scheme using Data Partitioning that simply adapts the video bit rate depending on the subscriber quality line. The optimal bit rates are automatically chosen according to the line characteristics so that visual degradations of the video are minimized. In this goal, a new video quality metric that is very simple to implement is proposed to assess MPEG-2 sequences. On the channel coding side, a complete study of bi-resolution transmission schemes over DMT channel presents a comparison of two hierarchical transmission schemes: the Frequency Division Multiplexing schema and the Embedded MultiCarrier Modulation Scheme that uses hierarchical QAM to transmit bits of the two layers on the same sub carrier. This study leads to the proposal of two new bit and power loading algorithms for the two different transmission schemes. The final analysis of the system and experimental results highlight advantages of the suggested solution compared to a classical monoresolution transmission
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Kanj, Hind. "Zero-Latency strategies for video transmission using frame extrapolation." Electronic Thesis or Diss., Valenciennes, Université Polytechnique Hauts-de-France, 2024. https://ged.uphf.fr/nuxeo/site/esupversions/53e0c0d3-296e-477f-9adc-2dbc315128f5.
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La demande de diffusion sans interruption de contenu vidéo et de haute qualité avec une latence minimale est essentielle dans les applications telles que la diffusion sportive et le contrôle de systèmes à distance. Cependant, la diffusion vidéo reste exposée à des défis en raison des caractéristiques variables des canaux de communication, qui peuvent avoir un impact sur la qualité de l'expérience en termes de qualité vidéo et de latence de bout en bout (le temps entre l'acquisition de la vidéo à l'émetteur et son affichage au récepteur).L'objectif de cette thèse est d'aborder le problème des applications en temps réel avec transmission unicast du serveur au client, telles que les applications de contrôle à distance, tout en maintenant une bonne qualité. Nous testons l'efficacité d'une technique récente d'apprentissage profond pour la compensation de la latence dans le schéma de transmission vidéo et son impact sur la qualité. Cette technique prédit les images futures à l'aide des images précédentes disponibles, ce qui permet d'afficher les images au moment voulu. Les résultats montrent que l'extrapolation est prometteuse, en particulier pour les contenus avec peu d'informations temporelles. Cependant, elle doit encore être améliorée en termes de qualité, de prédiction à long terme et de délai d'extrapolation.Plusieurs études se concentrent sur l'intégration d'un système hybride numérique-analogique pour améliorer la qualité perceptive, profitant des avantages des méthodes numériques et analogiques. Nous étudions l'efficacité d'un schéma hybride à faible latence en termes de réduction de la latence tout en maintenant une qualité vidéo élevée. Les résultats montrent que le système hybride améliore la qualité de la vidéo reçue dans la plupart des cas. Cependant, les artefacts d'extrapolation surpassent les artefacts d'encodage et masquent les avantages des schémas hybrides. Ainsi, l'amélioration des performances des schémas hybrides repose sur l'amélioration de l'extrapolation.En plus, les méthodes de diffusion adaptative HTTP ont prouvé leur efficacité pour améliorer la qualité de l'expérience en ajustant le débit d'encodage en fonction des conditions du canal. La plupart de ces algorithmes sont utilisés au client, ce qui pose des problèmes pour répondre aux exigences de latence des applications en temps réel. Dans ces applications, les vidéos sont acquises, compressées et transmises à partir de dispositifs jouant le rôle de serveurs. Donc, ces méthodes pilotées par le client ne conviennent pas à cause de la variabilité des conditions du canal. En plus, la prise de décision se fait avec une périodicité de l'ordre de la seconde, ce qui n'est pas assez réactif lorsque le serveur se déplace, ce qui entraîne des retards importants. Il est donc important d'utiliser une granularité d'adaptation plus fine. Nous visons à contrôler la latence de bout en bout tout en garantissant une qualité d'expérience élevée. Un contrôle du débit d'encodage au niveau d'image à l'émetteur est combiné à une extrapolation au récepteur pour compenser le retard de bout en bout. Le contrôle du débit au niveau d'image permet au système de s'adapter aux variations soudaines des conditions du canal. Un retard apparent de bout en bout nul peut être atteint au prix d'une perte de qualité du signal. Les algorithmes existants tentent d'optimiser les sources individuelles de retard dans le schéma de diffusion vidéo, mais pas de réduire la latence de bout en bout et d'atteindre une latence nulle. Un «Model Predictive Control» impliquant le niveau de mémoire tampon à l'émetteur et l'estimation du débit canal est utilisée pour trouver la valeur optimale du débit d'encodage pour chaque image. Il ajuste dynamiquement le compromis entre le débit de codage et l'horizon d'extrapolation, tout en prévoyant l'impact de la décision relative au débit d'encodage sur les images futures, pour améliorer la qualité d'expérienceThe demand for seamless, high-quality video content delivery with minimal latency is paramount in today's applications such as sports broadcasting, videoconferencing, and remote system control. However, video delivery still faces challenges due to unpredictable nature of communication channels. The variations in channel characteristics can impact the quality of experience in terms of content quality and End-To-End latency - the time elapsed between video acquisition at the transmitter and its display at the receiver.The aim of this thesis is to address the issue of real time applications with unicast transmission from server to client such as remote control applications, while maintaining a good quality. We test the effectiveness of a recent deep learning technique for latency compensation in the video transmission scheme and its impact on video quality. This technique predicts future frames using available previous frames, allowing the end-user to display the images at the desired time. The results demonstrate the promise of extrapolation, especially for content with low temporal information. However, it still needs to be improved in terms of quality, long-term prediction, and extrapolation delay.Various studies focus on the integration of a hybrid digital-analog scheme to improve the perceptual quality, taking advantage of the strengths of both digital and analog methods. We study the effectiveness of low-latency hybrid scheme in term of reducing latency while maintaining high video quality. The results show that the hybrid scheme improves the quality of the received video in most cases. However, the extrapolation artifacts outweigh encoding artifacts and mask the advantages of hybrid schemes. Thus, the improvement in hybrid scheme performance relies on the enhancement of extrapolation.Moreover, HTTP Adaptive Streaming methods have proven their effectiveness in improving the quality of experience by dynamically adjusting the encoding rate based on channel conditions. However, most of these adaptation algorithms are implemented at the client level, which poses challenges in meeting latency requirements for real time applications. In addition, in real time application, videos are acquired, compressed, and transmitted from the device acting as the server. Therefore, client-driven rate adaptation approaches are not suitable due to the variability of the channel characteristics. Moreover, in these methods, the decision-making is done with a periodicity of the order of a second, which is not reactive enough when the server is moving, leading to significant delays. Therefore, it is important to use a finer adaptation granularity in order to reduce the End-To-End delay. We aim to control the End-To-End latency during video delivery while ensuring a high quality of experience. A frame-level encoder rate control at the transmitter side is combined with a frame extrapolation at the receiver side to compensate the End-To-End delays. Frame-level rate control enables the system to adapt to sudden variations of channel characteristics. Null apparent End-To-End delay can be reached at the price of some signal quality. To the best of our knowledge, state-of-the-art algorithms try to optimize the individual sources of delay in the video delivery scheme, but not to reduce the whole End-To-End latency and achieve zero latency. A model predictive control approach involving the buffer level at the transmitter and the throughput estimation is used to find the optimal value of encoding rate for each frame. It dynamically adjusts the trade-off between the encoding rate and the extrapolation horizon at the receiver, while predicting the impact of the encoding rate decision on future frames, thus providing the best quality of experience
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Madurga, Martín-Serrano Juan Lucas. "A method for a small web site to add some sharing features." Thesis, Linköping University, Department of Science and Technology, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-11006.
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The aim of this diploma work is to compare and evaluate different methods to enable small web sites to make available videos which will be shared the users. Storage and bandwidth problems of small web sites are taken into account. The requirements of the system were defined as: configurable, feasible, easy use and easy to integrate. Existing solutions and different implementation alternatives are analyzed. With a tool based upon a CMS, using recordings residing on powerful dedicated video providers and with AJAX “technology”, the criteria are fulfilled. As part of the investigation, a prototype tool based upon TYPO3 has been implemented.
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Skogsberg, Jonatan. "Motstånd och utveckling : Att via video få återkoppling på sitt psykoterapeutiska arbete." Thesis, Stockholms universitet, Klinisk psykologi, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-169946.
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Det finns tekniska möjligheter att spela in psykoterapi, för forskning, utveckling och kvalitetssäkring, men tekniken är underanvänd. Den aktuella studien vill undersöka vad som påverkar terapeuters benägenhet att använda video och hur man kan förstå terapeuters motstånd mot video. Terapeuter intervjuades och deras svar analyserades via tematisk analys. Resultatet visar att följande faktorer påverkar terapeuters användning av video: teknik, juridik, patientens motstånd, struktur, syfte, motstånd, självkritik och utveckling. Att använda video i den terapeutiska situationen förstås som något som kan ge stora möjligheter till utveckling men till en stor känslomässig ansträngning. Videons påverkan på det psykoterapeutiska samtalet är komplex och motiverar fortsatt forskning.
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McNeal, Jean Pulis. "Site Facilitation of Distance Education via Compressed Video in Rural Schools: a Case Study." Diss., Virginia Tech, 1998. http://hdl.handle.net/10919/30409.
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Distance education delivered via broadband networks and sophisticated electronic technologies is one innovation often recommended for helping rural schools and their communities provide students with curricula and educational opportunities necessary for success in a global economy. This case study explored how eight rural Virginia school systems with little prior experience involving these technologies implemented a regional telecommunications network (SVCC-TN, part of Net.Work.Virginia). Over a one year period, 54 administrators, teachers, and students (representing nine schools) joined together in multi-role telecommunications teams to learn how the technology functioned and could enhance teaching and learning opportunities, and then facilitated implementation at their local sites.
The following questions were addressed: (a) How was the process of implementing distance education initially characterized? (b) What barriers did schools face? (c) How did school teams function? (d) How did this process affect perceived attitudes, concerns, and self-efficacy of participants? and (e) In what ways did individuals and schools redefine, reorganize or reinvent the initial process in order to optimize implementation?
Qualitative research methods, supported by qualitative and quantitative data collection instruments, were utilized. Teachers and administrators on school telecommunications teams completed questionnaires at the start and close of the study that addressed attitude, concerns (measured via Concerns-Based Adoption Model [CBAM] instrument) and self-efficacy. Additional data was obtained from analysis of open-ended surveys; focus group transcripts; documents; interviews; and researcher notes, comments, and observations of workshops and meetings attended by school teams and superintendents.
The outcomes of this study identified that both technical and top-level institutional leadership are needed to support full-scale implementation of distance education within a regional consortium and that a multi-role collaborative approach to staff development utilizing hands-on strategies is an effective strategy for enhancing participants' self-efficacy towards technology. Findings identified (1) barriers and drivers of distance education; (2) initial programming strategies; and (3) needs to cultivate a wider audience of users, increase communications, and establish new organizational structures for promoting cross-district utilization of distance education. Recommendations are presented for enhancing distance education in rural schools.Ed. D.
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Hargroves, Ryan. "Reach Campaigns and Self-promotion on Social Networking Sites : hidden Algorithms at Work in Selected Vloggers' Videos." Diss., University of Pretoria, 2020. http://hdl.handle.net/2263/75553.
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The ways in which people present themselves online to others is a growing point of interest for scholars in a multiplicity of academic fields. On the common ground of self-representation, the concept of reach campaigns is used as a hermeneutical tool to analyse and interpret the postings and uploaded videos of five selected vloggers to work towards a way to explain the hidden algorithms at work on Social Networking Sites. The purpose of reach campaigns is not to replace terms such as ideology, or hegemony, nor does it serve to categorize or limit certain trends and currents but rather aims to provide a means to discuss human interactions with technology and more specifically – digital technology, working in and around the fields of cultural analytics and visual studies. One of the most notable visualities to emerge from the human-technology relationship is that of the self-representation. Vlogging has become one of the most popular means of self-representation online and through the lens of reach campaigns, it is proposed that a contemporary understanding of online self-representation can be achieved. While a large majority of vlogging’s conception occurs online, algorithms could be seen as a predominant influencing factor. This dissertation seeks to explore how algorithms may affect the promotion of four YouTube vlogger’s videos.Dissertation (MA (Visual Studies))--University of Pretoria, 2020.
NRF
Visual Arts
MA (Visual Studies)
Unrestricted
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Labouret, Stéphane. "Détermination du taux de vide d'un champ de bulles de cavitation ultrasonore par une méthode hyperfréquence : corrélation du taux de vide et de la puissance du bruit de cavitation." Valenciennes, 1998. https://ged.uphf.fr/nuxeo/site/esupversions/e5dc6fee-0e7e-4a6e-8d10-b4209ceaf46f.
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Ce travail est consacré à l'étude des champs de bulles produits par cavitation ultrasonore, et qui sont à l'origine de nombreux phénomènes chimiques, physiques et mécaniques. Son objectif est de caractériser le volume total des bulles, ou taux de vide, et d'évaluer leur distribution en tailles. L’évolution du taux de vide est déterminée en suivant le décalage que provoque la présence des bulles sur de la fréquence de résonance d'une cavité électromagnétique résonante hyperfréquence (400 mhz) contenant le milieu insonifié. Sous certaines conditions, le décalage de fréquence est proportionnel au taux de vide. La distribution en tailles des bulles est déterminée en analysant la dissipation du taux de vide après la fin de l'insonification, à partir de la loi de dissolution des bulles libres. La distribution en tailles obtenue est celle des bulles présentes dans la cavité 40 secondes après la fin de l'insonification. Les évolutions du taux de vide et de la distribution en tailles des bulles ont été étudiées en fonction des paramètres suivants : pression acoustique, viscosité de l'eau, durée d'insonification, concentration en air dissous, mode d'insonification continu ou découpé et fréquence acoustique. Plusieurs seuils caractéristiques du comportement des bulles ont été mis en évidence. Pour une eau saturée en gaz, la croissance du taux de vide est corrélée avec la puissance du bruit de cavitation. Les contributions à la puissance du bruit de cavitation des oscillations fortement non linéaires et des implosions ont pu être estimées. La méthode de mesure mise au point est un outil bien adapte à l'étude des champs de bulles produit par cavitation ultrasonore.
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Marchevska, Elena. "The screen as a site of division and encounter." Thesis, University of Northampton, 2012. http://nectar.northampton.ac.uk/6130/.
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This study is a practice-based exploration of the screen as a border site, where the concepts of division and encounter are performatively examined. My research strategy is shaped by applying autoethnographic performance strategies to the mediated space of the screen. Media materials (photos, videos and blog entries) are created with mobile media devices used in performative situations, offering a theoretical framework originating in practice. The main argument is that the screen is an assemblage site, where the notions of division and encounter can be artistically explored. Furthermore, the screen is explored as an object, as a metaphor and as an idea. By linking the Latour notion of “assemblage” with Colley’s exploration of the personal use of mobile screens (“autobiometry”), and Ettinger’s notion of “borderspace” as site of artistic encounter, the practices presented in this thesis are located in a field that blurs the boundary between the personal and art; autobiography and autoethnography; technology and identity. In so doing, this thesis expands on previous explorations such as “boundary event” (Trinh T. Minh-ha 1999); “soft mastery” (Turkle 1995); and “screen-reliant art” (Moldoch 2010;). In the performative media materials created for this thesis, the screen is explored through a “processual approach” (Bacon, 2006). This enabled me to examine the nature of interaction with the screen through embodied reflexive practice. This approach firmly places the work in the experiential or performative realm. Key practices that are discussed in this thesis include among others, an earth body performative project by Ana Mendieta (Cuba/USA) entitled Silueta series (1973-1980), a live art work by Tanja Ostojic (Serbia/Germany) called Looking for a husband with EU passport (2000-2005) and my own performative media pieces, Valid until… (2010) and The place where we were last together (2011).
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Zwingelstein, Marie. "Etude de l'optimisation d'un système DMT-ADSL : application à la transmission video MPEG-2 en mode hiérarchique." Valenciennes, 1999. https://ged.uphf.fr/nuxeo/site/esupversions/4b8844ca-e7ac-4cb4-81df-9d40eda5bd20.
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Le travail présenté dans cette thèse se rapporte au système de transmission numérique ADSL (asymétrique digital suscrite line), dont le principe est d'exploiter les lignes téléphoniques d'abonnés existantes en paire torsadée cuivrée pour assurer une transmission de données à un débit de plusieurs mégabits par seconde. Un des éléments clés de l’ADSL est d'utiliser la modulation multi porteuse DMT (discrète multizone) qui permet d'adapter facilement le signal émis au canal de transmission par le biais du choix des répartitions fréquentielles du débit et de la puissance. Après avoir rappelé comment ces répartitions influencent le TEB (taux d'erreur par bit) atteint, nous développons dans une première partie deux méthodes originales qui optimisent ces répartitions, avec des compromis performance/complexité différents. Pour les deux méthodes, nous proposons un calcul simple de la répartition fréquentielle du débit, optimal au sens de la capacité du canal. En ce qui concerne la puissance, la première méthode, optimale, détermine la répartition qui minimise le TEB, et la seconde, plus simple, celle qui satisfait à l'hypothèse habituelle et légèrement sous-optimale d'un TES (taux d'erreur par symbole) identique sur toutes les fréquences. Les résultats de simulation sur un ensemble de lignes CSA caractéristiques ont montré que les deux méthodes proposées aboutissent à des performances plus élevées que les méthodes courantes, en particulier les méthodes de Hughes-Hartogs et de Peter Chow, avec une complexité de calcul généralement inférieure. Dans la deuxième partie du travail, nous nous intéressons à l'application d'une transmission de données vidéo, codées suivant la norme internationale MPEG-2, sur ADSL. L'originalité repose sur le choix d'un mode de codage et de transmission bi-résolution qui privilégie les données vidéo les plus importantes au détriment des autres données, dans le but d'améliorer la qualité de service. Dans ce cadre, nous avons proposé trois architectures ADSL bi-résolution, agissant soit au niveau de la modulation DMT, soit au niveau du codage FEC (foirard errer correction), en attribuant des codes Reed-Solomon différents aux données importantes et moins importantes. Les résultats ont démontré la validité de tels schémas, avec, compte tenu d'une proportion voisine de 30% pour les données importantes, une réduction du TEB des données importantes d'un facteur 100 par rapport au TEB mono-résolution, alors que le teb des données moins importantes n'est augmente que d'environ un facteur 2The work presented in this thesis is related to the digital transmission system ADSL (Asymmetric Digital Subscriber Line) which uses existing subscriber lines in copper twisted pairs to transmit data at several megabits per second. One key element of ADSL to use DMT (Discrete MultiTone) modulation to adapt the transmitted signal to the channel thanks to the choice of frequency bit and power loading. In a first part, a brief review of bit and power loading influence on the BER (Bit Error Rate) leads us to propose two original loading methods of different compromise performance / complexity. For both methods, the bit loading is simply calculated to match with the optimum of channel capacity. Regarding power, the first method (optimal) allocates it to minimize the BER, and the second one (more simple) so that the conventional and slightly sub-optimal equal SER (Symbol Error Rate) assumption is satisfied. Simulation results on characteristic ADSL loops have shown that both proposed methods perform better than the conventional ones, in particular the Hughes-Hartogs’ and the Peter Chow’s. The second part of the work is dedicated to MPEG-2 video transmission on ADSL. The originality is to use a bi-resolution modulation and transmission scheme which provides a high degree of protection to the most important data to the prejudice of less important data, so that the QoS (Quality of Service) is improved. In this context, we have presented three different architectures for a bi-resolution ADSL system. They act either at the DMT modulation level, or at the FEC (Forward Error Correction) level by differentially Reed-Solomon encoding important and less important data. The results have shown the validity of these kinds of architectures. For a typical ratio of most important data equal to 30%, the BER of most important data can be divided by 100 in comparison with the mono-resolution BER, whereas the BER for less important data is only multiplied by 2
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Larsson, Fredrik, and Olle Petersons. "Den vises väg till framgång : En fallstudie om hur företag kan identifiera rätt marknadssegment för sitt varumärke." Thesis, Örebro universitet, Restaurang- och hotellhögskolan, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:oru:diva-62868.
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Pommeray, Michel. "Etude d'un vidéoprojecteur laser stéréoscopique." Valenciennes, 1995. https://ged.uphf.fr/nuxeo/site/esupversions/9fd20f01-dce5-49a3-b087-e8faf2cfc241.
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After a review of the main three-dimensional display techniques, this report proposes a study of a laser videoprojector, which allows the two images of a stereo-pair to be seen simultaneously. The left and right images correspond to two orthogonal polarization directions of the laser beam. So, for each pixel, an intensity and a polarization angle are computed from the pixel intensities of the left and right images. At restitution, special polarizing glasses worn by the viewer decode the polarized images to provide the left and right eye views. As images are projected in waves of four lines to reduce the rotation speed of the polygonal mirror doing horizontal scanning, the laser beam is diffracted by a multifrequency acousto-optic modulator. The linearization of the diffraction efficiencies is realized by the introduction of an additional acoustic carrier. A suitable anisotropic interaction greatly reduces the multiple rediffraction effects. The polarization angle of the light beams stemming from the acousto-optic component can not be modulated independently by the electro-optic modulator. A study of the image degradation, in both spatial and frequency domains, is presented, in case the intensities are averaged over two successive lines of a screen for each image. Next a second method, indemnifing the absence of ghost images and minimizing the mean square error, is analysed, then compared to the previous one with the help of a set of numerical results and simulationsPrès une analyse des principales techniques de restitution du relief, ce mémoire propose l'étude d'un vidéoprojecteur laser, autorisant la visualisation simultanée des deux images d'un couple stéréoscopique. Les images gauche et droite du couple correspondent à deux directions de polarisation orthogonales du faisceau laser. Ainsi, pour chaque pixel, une intensité et un angle de polarisation sont calcules a partir des intensités des pixels des images gauche et droite. A la restitution, les lunettes a verres polarises orthogonalement, portées par le spectateur, adressent a chaque il l'image qui lui est destinée. La projection des images s'effectuant par paquet de quatre lignes, de manière a réduire la vitesse de rotation du miroir polygonal assurant le balayage horizontal, le faisceau laser est diffracte et module en intensité par un composant acousto-optique multifréquence. La linéarisation des rendements de diffraction de ce dernier est réalisée par l'adjonction d'une voie supplémentaire, dite de compensation. Les phénomènes d'intermodulation sont réduits par le choix d'une coupe acoustique particulière dans la paratellurite. Le modulateur électro-optique ne permet pas la modulation indépendante de l'angle de polarisation des faisceaux lumineux issus du composant acousto-optique. Une étude, dans le domaine spatial et fréquentiel, de la dégradation des images, qui s'en suit, est présentée dans le cas ou les intensités sont moyennées sur deux lignes consécutives d'une trame, pour chaque image. Une seconde méthode, minimisant l'erreur quadratique moyenne, est ensuite analysée, puis comparée à la précédente à l'aide d'un ensemble de résultats numériques et de simulations
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Winblad, Emanuel. "Visualization of web site visit and usage data." Thesis, Linköpings universitet, Medie- och Informationsteknik, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-110576.
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This report documents the work and results of a master’s thesis in Media Tech- nology that has been carried out at the Department of Science and Technology at Linköping University with the support of Sports Editing Sweden AB (SES). Its aim is to create a solution which aids the users of SES’ web CMS products in gaining insight into web site visit and usage statistics. The resulting solu- tion is the concept and initial version of a web based service. This service has been developed through an agile process with user centered design in mind and provides a graphical user interface which makes high use of visualizations to achieve the project goal.
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Lalys, Florent. "Automatic recognition of low-level and high-level surgical tasks in the operating room from video images." Phd thesis, Rennes 1, 2012. https://ecm.univ-rennes1.fr/nuxeo/site/esupversions/2186a1f7-f586-43c5-b037-6585b5c22aef.
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La besoin d’une meilleure intégration des nouveaux systèmes de chirurgie assisté par ordinateur dans les salles d’opération à récemment été souligné. Une nécessité pour atteindre cet objectif est de récupérer des données dans les salles d’opérations avec différents capteurs, puis de à partir de ces données de créer des modèles de processus chirurgicaux. Récemment, l'utilisation de vidéos dans la salle d'opération a démontré son efficacité pour aider à la création de système de CAO sensible au contexte. Le but de cette thèse était de présenter une nouvelle méthode pour la détection automatique de tâches haut niveaux (i. E. Phases chirurgicales) et bas-niveaux (i. E. Activités chirurgicales) à partir des vidéos des microscopes uniquement. La première étape a consisté à reconnaitre automatiquement les phases chirurgicales. L'idée fut de combiner des techniques récentes de vision par ordinateur avec une analyse temporelle. Des classifieurs furent tout d’abord mis en œuvre pour extraire des attributs visuels et ainsi caractériser chaque image, puis des algorithmes de classification de séries temporelles furent utilisés pour reconnaitre les phases. La deuxième étape a consisté à reconnaitre les activités chirurgicales. Des informations concernant des outils chirurgicaux et des structures anatomiques furent détectées et combinées avec l'information de la phase précédemment obtenu au sein d’un système de reconnaissance intelligent. Après des validations croisées sur des vidéos de neurochirurgie et de chirurgie de l’œil, nous avons obtenu des taux de reconnaissance de l'ordre de 94% pour la reconnaissance des phases et 64% pour la reconnaissance des activités. Ces systèmes de reconnaissance pourraient être utiles pour générer automatiquement des rapports post-opératoires, pour l'enseignement, l’apprentissage, mais aussi pour les futurs systèmes sensibles au contexteThe need for a better integration of new Computer-Assisted-Surgical systems in the Operating Room (OR) has been recently emphasized. One necessity to achieve this objective is to retrieve data from the OR with different sensors, then to derive models from these data for creating Surgical Process Models (SPMs). Recently, the use of videos from cameras in the OR has demonstrated its efficiency for advancing the creation of situation-aware CAS systems. The purpose of this thesis was to present a new method for the automatic detection of high-level (i. E. Surgical phases) and low-level surgical tasks (i. E. Surgical activities) from microscope video images only. The first step consisted in the detection of high-level surgical tasks. The idea was to combine state-of-the-art computer vision techniques with time series analysis. Image-based classifiers were implemented for extracting visual cues, therefore characterizing each frame of the video, and time-series algorithms were then applied to model time-varying data. The second step consisted in the detection of low-level surgical tasks. Information concerning surgical tools and anatomical structures were detected through an image-based approach and combined with the information of the current phase within a knowledge-based recognition system. Validated on neurosurgical and eye procedures, we obtained recognition rates of around 94% for the recognition of high-level tasks and 64% for low-level tasks. These recognition frameworks might be helpful for automatic post-operative report generation, learning/teaching purposes, and for future context-aware surgical systems
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Toler, Richard L. Jr. "Structural Equation Modeling of Advertising Involvement, Consumer Attitude, and Engagement for Video Advertising in a Social Networking Site." Thesis, Northcentral University, 2017. http://pqdtopen.proquest.com/#viewpdf?dispub=10598949.
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A majority of marketers plan to increase their investment in online marketing messaging to reach an expanding population of potential consumers using online social networking platforms. The problem addressed in this study was a marketer’s inability to determine the most effective video advertising in a social networking site to increase consumer attitude and engagement. A non experimental quantitative survey study was used to gather data to test a unique hypothesized structural equation model based on the theory of advertising involvement and the affect transfer theory. The purpose was to examine the relationships among the factors of consumer attitude, defined as attitude toward the advertising and attitude toward the brand, the second order construct of advertising involvement, and the consumer engagement behaviors of sharing intention and purchase intention. Participants were recruited from the student body of a community college located in a major metropolitan city in the southwest United States. Data analysis consisted of summary descriptive statistics, confirmatory factor analysis (CFA), and structural equation modeling (SEM). The objective of the research was to contribute to the theoretical body of knowledge by demonstrating the generalizability of the theory of advertising involvement to video advertising. The measurement model was a good fit to the data, CFI = 1.00, RMSEA = 0.000. Findings indicated that the theory of advertising involvement, first validated in the context of static advertising, is useful in understanding the relationship of the factors in the context of video advertising.
Attitude toward the advertising played a significant mediating role between advertising involvement and the two factors, attitude toward the brand and sharing intention. Attitude toward the brand played a significant mediating role between advertising involvement and the two factors of sharing intention and purchase intention. Attitude toward the advertising had no significant influence on purchase intention. The structural model can serve as a useful tool in evaluating video advertising in a social networking site. Future research with the model should be conducted with different types of products, different types of videos, and different consumer populations.
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Ma, Richard. "Video-based tutorial on web design for the technophobic teacher." CSUSB ScholarWorks, 2001. https://scholarworks.lib.csusb.edu/etd-project/1975.
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The aims of this project hope to trace the factors affecting teachers' use of technology, with a concentration on Internet usage, and offer steps in helping teachers move toward integrating the Internet into their curriculum.
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Santos, Thiara Ribeiro. "Saiba como funciona e seja feliz: estudo das modalizações dos saberes nos sites instrucionais." Pontifícia Universidade Católica de São Paulo, 2012. https://tede2.pucsp.br/handle/handle/4424.
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Previous issue date: 2012-08-07Conselho Nacional de Desenvolvimento Científico e Tecnológico
This research is focused on the user agreements of sites specialized in instruction videos that propagate modal guides which indicate how the users-recipients of the information should be and should do in many daily tasks. The orientations on how to act are offered through recipes that instruct provide a step by step guide to complete all the requirements for successful completion of actions. This project will analyse how the sites are categorized and how the topics are organized to their readers. Beauty, health and lifestyle are examples of topics related to personal appearance, the contents to be covered in the research corpus. A map of communication devices that exist within the sites will be created and investigated, beginning from the modal arrangements of the to do and to know operated within the establishment of communication contracts, the effects of meaning that derive from the texts in order to identify the existence of modalizations and instigation of the consumption. The research questions are the following: what are the devices that fortify the communication contracts within the sites? How are the readers summoned? How is the biopolitical program proposed? How does the modalizations happen? How does the navigation of the site take place? How is organized the distribution of thematic schedules concerning the ways to donate competence to the users? Is there encouraging material consumption (indications of stores) and immaterial consumption (encouraging new skills/ knowledge) through the topics explored? The corpus consists of 14 sites: 5min, About.com, Ask, Askmen, Como fazer as coisas, Doityourself, eHow, Helpfulvideo, Howcast, MonkeySee, Saber Hacer, Videojug, Wikihow and Wonderhowto. The investigation of the most used devices will be evidenced to identify the discursive strategies of the enunciators. We also elaborate the map of the categories of the video classes that are in the sites and organizations of the arguments of this projetc based on the speeches and theories abou self-help, biopolitics, daily, hypermedia narratives, cyberspace and postmodern consumption. The theoric fundamentation includes studies about the communication speeches as Charaudeau, Deleuze, Foucault and Semprini, in the field of cyberspace the theories of Trivinho, Rifkin and Castells, and other scholars such as Bauman, Prado, Freire Filho, Certeau and Greimas
Esta pesquisa estuda os contratos de comunicação de sites especializados em videoaulas que propagam guias modalizadores que indicam como os usuários-destinatários das informações devem-ser e devem-fazer inúmeras tarefas cotidianas. As orientações de como agir são ofertadas por meio de receitas que instruem passo a passo a realização de todas as etapas necessárias para a conclusão bem sucedida das ações. Analisaremos como os sites se categorizam e como dispõem as temáticas para os enunciatários. Beleza, saúde e comportamento são exemplos de temas relacionados à imagem pessoal, conteúdos a serem abordados no corpus da pesquisa. Realizaremos um mapeamento dos dispositivos comunicacionais existentes nos sites e investigaremos, a partir dos arranjos modais do fazer e do saber operados na instituição dos contratos de comunicação, os efeitos de sentido que provêm dos textos no intuito de identificarmos a existência de modalizações e instigação ao consumo. Foram levantadas as seguintes questões de pesquisa: quais são os dispositivos que fortalecem os contratos de comunicação nos sites? Como os enunciadores convocam os enunciatários? Como o programa biopolítico é proposto? De que forma as modalizações ocorrem? Como as navegações dos sites procedem? De que modo se organiza a distribuição dos agendamentos temáticos relativos aos modos de doar competência aos usuários? Há incentivo de consumo material (indicações de lojas virtuais e/ou físicas) e consumo imaterial (estimulando novos saberes/conhecimento) através das temáticas exploradas? O corpus é constituído por 14 sites: 5min, About.com, Ask, Askmen, Como fazer as coisas, Do it Yourself, eHow, Helpfulvideo, Howcast, Monkeysee, Saber Hacer, Videojug, Wikihow e Wonderhowto. A perscrutação dos dispositivos mais utilizados será evidenciada para identificar as estratégias discursivas dos enunciadores. Elaboraremos também um mapeamento das categorias de videoaulas dos sites e organização das argumentações deste projeto com base nos discursos e teorias sobre autoajuda, biopolítica, cotidiano, narrativas hipermidiáticas, cibercultura e consumo pós-moderno. A fundamentação teórica contempla os discursos comunicacionais conforme Charaudeau, Deleuze, Foucault e Semprini e no campo do ciberespaço as teorias de Trivinho, Rifkin e Castells, além de outros estudiosos como Bauman, Prado, Freire Filho, Certeau e Greimas
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Jonsson, Robert, and Kees Toor. "Sitt kvar, snart kan du välja din reklam : En kvalitativ studie om tittarnas attityder till valbart reklaminnehåll på webb-TV." Thesis, Södertörns högskola, Institutionen för kommunikation, medier och it, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:sh:diva-17092.
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Denna C-uppsats undersöker om tittarens attityder till marknadsföring på webb-TV kan förändras av en interaktiv tjänst som ger möjligheten att välja de reklamfilmer som ska presenteras. För att skaffa information använde vi oss av en empirisk studie som involverade fokusgruppsintervjuer med erfarna deltagare. Studien är därför baserad på respondenternas tidigare kunskap av webb-TV för att kunna jämföra dessa mot den nya experimentella implementerade tjänsten. Efter studien har vi funnit att attitydförändringar verkar har inträffat: Majoriteten av tittarna tycker att en valbar reklamtjänst skulle öka tittarupplevelsen till det bättre. Dock tycker en minoritet att valet leder till ett ytterligare moment som bedöms vara för tidskrävande.This c-level paper examines if viewers' attitudes towards advertisement may be influenced with an optional service that makes it possible to choose on which commercials will get presented while watching Web TV. To gather information, we used an empirical study that involved focus group interviews with experienced participants. The study is therefore based on respondents' previous knowledge of online video in order to compare these against the new experimentally implemented service. After the study we have found that attitude change seems to have occurred: The majority of viewers believe that a selectable advertising service would increase the viewing experience for the better. However, a minority thinks that it could lead to an additional step for user’s choice, which can be judged to be too time-consuming.
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Barber, James. "Installation art and memory : a practice-as-research exploration." Thesis, University of Plymouth, 2012. http://hdl.handle.net/10026.1/900.
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This practice-as-research project investigates how a piece of site-responsive Installation Art, titled Triple Point Dunnage (exhibited in Royal William Yard, June 2009), can be used to generate knowledge about memory work through experience of site. Working in dialogue with the ideas of Daniel C. Dennett, Lucy Lippard and Gaston Bachelard, I attempted to create a permeable and fluctuating creative setting for the memory work of participants. An approach that used site as a stimulant within a process which also incorporated theoretical themes. During the period of design and construction, I interacted with and recorded interviews with people who had a personal connection with the site or with an interest in how memory works. The final installation presented layers of spoken fragmented content in a dialectic relationship within the installation’s spatial construction. The responses of the installation’s visitors and participants were collated through a response book and interviews. These were analysed in order to discover to what extent, if at all, the properties I had developed and designed into the work had shaped the engagements of the participants. The multi-valented properties of the work generated an array of responses that suggested that the viewers had fashioned their experience by blending the fragmented stories of others with their own personal histories. This engagement resembles Dennett’s concept of “self-narrator” and resonates with Bachelard’s concept of the fusion of physical and psychological space and Lippard’s understanding of place. By exploring memory through site Triple Point Dunnage generated a sense of place that was a fusion of the participants’ responses to the external physical environment and their associative memories stimulated by the affective fragmented properties of the work.
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Conter, Marcelo Bergamin. "Imagem-Música em vídeos para web." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2012. http://hdl.handle.net/10183/49264.
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A presente dissertação propõe-se a investigar os modos com que a música sobrecodifica a linguagem audiovisual em vídeos para a web, criando novos processos de significação e complexificando a virtualidade musical (compreendida aqui como a totalidade irrepresentável de imagens que a expressam). O site YouTube se estabelece como um lócus privilegiado para tal estudo, pois nele encontra-se uma quantidade significativa de vídeos musicais em que a música se manifesta em todos os elementos audiovisuais, interferindo nos processos de composição audiovisual (tanto na trilha visual quanto na sonora). O que pode deste encontro derivar são atualizações e potencialidades do virtual da música, manifestadas como imagemmúsica. Os vídeos que constituem o corpus são organizados em quatro categorias mais recorrentes, ordenados de acordo com a proximidade que têm com a linguagem do videoclipe, o que permite perceber como, progressivamente, nos vídeos para web, está ocorrendo um processo de autonomização da imagem-música: mashup audiovisual; sampling audiovisual; spoof de shreds; auto-tunning. Essas práticas já estavam contidas, em potência, em audiovisuais anteriores, no cinema, na televisão, na videoarte, no videoclipe – e também nas práticas da música eletrônica –, mas somente na web elas conseguiram se manifestar a pleno. Como referencial teórico para compor o modo como será observado o fenômeno, utilizar-seão as teorias do filósofo Henri Bergson para compreender a virtualidade da música; de Gilles Deleuze, para entender os processos de significação que a sobrecodificação da música exerce sobre o audiovisual, e como ela movimenta suas estruturas através de tal processo; de Nicklas Luhmann, para compor um ponto de observação para os vídeos musicais para web diferente do que tradicionalmente se dirige ao videoclipe televisivo; e de Vilém Flusser, para compreender a natureza das imagens técnicas. Conclui-se que os vídeos para web estudados efetivamente se apartam da lógica do videoclipe televisivo, parte por não dialogarem com a lógica da indústria fonográfica, parte porque a música é resultado da montagem, e não o contrário, como ocorre normalmente em videoclipes; além disso, evidencia-se que a música é capaz de imprimir algo de si nos audiovisuais estudados, e que está ocorrendo uma tendência para a diluição da distinção entre arte figurativa e música: através desses vídeos, mostra-se possível a produção de música imaginativa, derivada da reciclagem de material audiovisual disponível na web.The present dissertation proposes to investigate how music over-codifies the audiovisual language of web videos, creating new signification processes and complexifying the musical virtuality (here understood as the unrepresentable totality of images that express it). YouTube’s website is established as a privileged locus for such study because it contains a significant amount of music videos in which music manifests itself in every audiovisual element, interfering in the audiovisual composing process (both in the visual and the sound tracks), which is edited according to musical rules. What may come from this encounter are updates and potentialities from the music’s virtual, manifested in the form of what will be here understood as image-music. The videos that compose the work's corpus are organized in four categories that are defined according to videoclip's language proximity: audiovisual mash up, audiovisual sampling, shreds spoofs, and auto-tuning. This procedure allows us to perceive how, progressively, in web videos, an empowerment of music-image is occurring. These practices were already contained, potentially, in previous audiovisuals, like cinema, television, video art and video clips – and also on electronic music practices –, but only in the web they managed to be fully manifested. Different theories will be presented and utilized as theoretical references, like those of French philosopher Henri Bergson, which will be used to comprehend music’s virtuality; works from Gilles Deleuze, will be utilized to aid our understanding of the signification processes that music’s over-codification performs on audiovisual, and how its structure is altered by it through this process; from Nicklas Luhmann's theories will provide a different point of view, on web music videos; and Vilém Flusser’s works will be employed to understand the nature of the technical image. We conclude that the web videos analyzed effectively move away from the logic of television music video, first, because they do not dialogue with the recording industry’s logic; second, because the songs created result from editing and not the other way around, as often occurs in video clips; third, it becomes clear that music is able to print something out of itself on the studied videos, there is an ongoing tendency for the dilution of the distinction between figurative art and music; throughout these videos, the production of imaginative music becomes possible, created from the recycling of audiovisual material available on the web.
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Terrisse, Robin. "Flux vacua and compactification on smooth compact toric varieties." Thesis, Lyon, 2019. http://www.theses.fr/2019LYSE1144/document.
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L’étude des vides avec flux est une étape primordiale afin de mieux comprendre la compactification en théorie des cordes ainsi que ses conséquences phénoménologiques. En présence de flux, l’espace interne ne peut plus être Calabi-Yau, mais admet tout de même une structure SU(3) qui devient un outil privilégié. Après une introduction aux notions géométriques nécessaires, cette thèse examine le rôle des flux dans la compactification supersymétrique sous différents angles. Nous considérons tout d’abord des troncations cohérentes de la supergravité IIA. Nous montrons alors que des condensats fermioniques peuvent aider à supporter des flux et générer une contribution positive à la constante cosmologique. Ces troncations admettent donc des vides de Sitter qu’il serait autrement très difficile d’obtenir, si ce n’est impossible. L’argument est tout d’abord employé avec des condensats de dilatini puis améliorer en suggérant un mécanisme pour générer des condensats de gravitini à partir d’instantons gravitationnels. Ensuite l’attention se tourne sur les branes et leur comportement sous T-dualité non abélienne. Nous calculons les configurations duales à certaines solutions avec D branes de la supergravité de type II, et examinons les flux ainsi que leurs charges afin d’identifier les branes après dualité. La solution supersymétrique avec brane D2 est étudiée plus en détails en vérifiant explicitement les équations sur les spineurs généralisés, puis en discutant de la possibilité d’une déformation massive. Le dernier chapitre fournit une construction systématique de structures SU(3) sur une large classe de variétés toriques compactes. Cette construction définit un fibré en sphère au-dessus d’une variété torique 2d quelconque, mais fonctionne tout aussi bien sur une base Kähler-EinsteinThe study of flux vacua is a primordial step in the understanding of string compactifications and their phenomenological properties. In presence of flux the internal manifold ceases to be Calabi-Yau, but still admits an SU(3) structure which becomes thus the preferred framework. After introducing the relevant geometrical notions this thesis explores the role that fluxes play in supersymmetric compactification through several approaches. At first consistent truncations of type IIA supergravity are considered. It is shown that fermionic condensates can help support fluxes and generate a positive contribution to the cosmological constant. These truncations thus admit de Sitter vacua which are otherwise extremely difficult to get, if not impossible. The argument is initially performed with dilatini condensates and then improved by suggesting a mechanism to generate gravitini condensates from gravitational instantons. Then the focus shifts towards branes and their behavior under non abelian T-duality. The duals of several D-brane solutions of type II supergravity are computed and the branes are tracked down by investigating the fluxes and the charges they carry. The supersymmetric D2 brane is further studied by checking explicitly the generalized spinor equations and discussing the possibility of a massive deformation. The last chapter gives a systematic construction of SU(3) structures on a wide class of compact toric varieties. The construction defines a sphere bundle on an arbitrary two-dimensional toric variety but also works when the base is Kähler-Einstein
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Burks, Andrea Nia. "USERNAME TAB PASSWORD RETURN." VCU Scholars Compass, 2009. http://scholarscompass.vcu.edu/etd/1815.
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Nakagori, Ryuji. "Matisse : le degré zéro de la couleur ou l'influence du zen." Valenciennes, 2000. https://ged.uphf.fr/nuxeo/site/esupversions/faeaad33-3224-45c8-9d0c-903ad1262d4e.
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On sait qu'Henri Matisse est un des plus grands orientalistes de nos jours. Depuis la révélation de la couleur par l'estampe japonaise au moment de la formation de son style fauve, l'art oriental n'a cessé de contribuer à l'abstraction radicale du pionnier de l'art moderne. Cette recherche a pour objet de faire la lumière sur l'influence de l'art de l'Extrême-Orient dans son art. D’une manière générale, ses engagements pour l'art de l'Extrême-Orient se marquent dans la simplicité de l'expression, et par la place donnée aux vides dans ses dessins calligraphiques et découpages. Je pense que cette caractéristique remarquable qu'attribue l'artiste à san-sui, style du paysage traditionnel chinois et japonais, se rattache à sa conception transcendantale de l'espace visuel, en tant que résurgence de sa conception de la création artistique, qui implique l'identification avec la nature. Nous reconsidérons ainsi la dynamique du système de la représentation sous-jacente de la composition plate du tableau par rapport à la métaphysique qu'il prête à "l'Orient", par la recherche de la couleur pure. Cela élucidera l'influence de l'art de l'Extrême-Orient qui ne se réduit pas aux exotismes orientaux, et propose une autre perspective pour resituer la conception de l'Orient dans l'histoire de l'art moderne.
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Eckert, Kristin D. "Use of the Internet for International News: A Comparative Content Analysis of the Television Evening Newscasts and Web Videos of the U.S. Stations PBS and NBC and the German Stations ARD and RTL." Ohio : Ohio University, 2009. http://www.ohiolink.edu/etd/view.cgi?ohiou1251323201.
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Thesis (M.S.)--Ohio University, August, 2009.Title from PDF t.p. Release of full electronic text on OhioLINK has been delayed until September 1, 2011. Includes bibliographical references (p. 89-102)
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Souza, Ricardo Araujo de. "Uma análise dos vídeos publicitários virais mais vistos no site Youtube.com no Brasil e no mundo: um olhar crítico do papel do marketing com ênfase no hiperconsumismo." Pontifícia Universidade Católica de São Paulo, 2014. https://tede2.pucsp.br/handle/handle/1103.
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Previous issue date: 2014-04-11This research believes that a relationship exists between the current paradigm crisis in Marketing with a one-dimensional and one-sided view of the relationship of the companies to the market and that theories such as Marketing and Service Co-creation already point to a multidimensional and bilateral vision between the company market and consumers. Even with the new signaling theories to a broader and bilateral, there is a vision myopia , especially in relation to the object of study of the National Marketing. The research believes that this object of study should be the society of hyperconsumption , construct designed by postmodern thinkers . With this construct various multidimensional , complex and dialogical marketing phenomena can be contextualized, such as Viral Marketing. This research then bases its theoretical basis in a model aligned with postmodern ideas about consumerism then to analyze the phenomenon of viral videos on Youtube , with special emphasis on the comparison between most viewed national and international viral video ads
Esta pesquisa acredita que existe uma relação entre a atual crise paradigmática do Marketing e a visão unidimensional e unilateral do relacionamento das empresas para com o mercado e que teorias como o Marketing de Serviço e a Cocriação já sinalizam para uma visão multidimensional e bilateral entre a empresa o mercado e os consumidores. Mesmo com as novas teorias sinalizando para uma visão mais ampla e bilateral, ainda ocorre uma miopia, principalmente em relação ao objeto de estudo do Marketing Nacional. A pesquisa acredita que este objeto de estudo deve ser a sociedade de hiperconsumo, constructo concebido pelos pensadores pós-modernos. Com este constructo vários fenômenos multidimensionais, dialógicos e complexos podem ser contextualizados, como por exemplo, o Marketing Viral. Esta pesquisa então fundamenta sua base teórica em um modelo alinhado com idéias pós-modernas sobre o consumismo para em seguida analisar o fenômeno dos vídeos virais no Youtube, com ênfase especial na comparação entre os vídeos publicitários virais nacionais e internacionais mais vistos
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Sanguinetti, Carolyn Anna Victoria. "Patterns in reef fish assemblages as determined by baited remote underwater video (BRUV) along the western side of False Bay: effects of site, depth and protection status." Master's thesis, University of Cape Town, 2013. http://hdl.handle.net/11427/9791.
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Includes bibliographical references.By protecting ecosystems from exploitation, no-take zones are considered the principal means by which marine species and their populations can be conserved for future generations. To be successful, no-take zones require continuous monitoring of the fish community to evaluate the response of marine ecosystems to anthropogenic impacts and environmental change. Obtaining an understanding of the patterns of species composition, abundance, and distribution, allows monitoring efforts to be focused, efficient, and properly interpreted. Baited remote underwater video (BRUV) was used to examine the effects of site, depth, andlevel of protection, on the diversity and relative abundance of temperate reef fish within the Table Mountain National Park (TMNP) Marine Protected Area (MPA). Four notake zones and adjacent exploited areas, subject to conventional management restrictions, were sampled monthly over a four-month period. A total of 36 species from three marine classes and 18 families was recorded. Species diversity (Shannon-Wiener index) was found to increase with sites closest to the mouth of the bay, whilst species abundance was found to increase with depth. Results indicated no consistent response to protection status among the sites at either the community or individual species level. However, the oldest no-take zone proclaimed for the purposes of reef conservation was found to harbour higher species diversity and a higher relative abundance of fish compared to its respective exploited area. Furthermore, the similar frequencies in which hottentot (Pachymetopon blochii) and roman (Chrysoblephus laticeps) were observed across the four study sites, suggests that these two commercially-important species are successfully recruiting inside and outside the no-take zones. These results indicate that physical factors, rather than protection status, within False Bay influence patterns of fish assemblage composition, abundance, and distribution. In future, and to improve comparability, assessments within the TMNP MPA should be designed to target similar locations and depth ranges within the bay. The success of no-take zones must be evaluated according to their individual design and management goals.
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Grimbert, Laurent. "Transmission vidéo MPEG-2 à deux niveaux de priorité sur réseau ATM." Valenciennes, 1998. https://ged.uphf.fr/nuxeo/site/esupversions/53ac8532-1075-48ef-b4f2-ddb3e1de701d.
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La nature variable et aléatoire du trafic vidéo MPEG-2 nécessite le contrôle du débit de chaque source à l'entrée du réseau ATM. Cependant, l'élimination des cellules en excès peut occasionner la perte d'une partie d'image, d'une image complète ou d'un groupe d'images entier dans les cas de pertes d'en-têtes MPEG-2. Pour pallier ce problème, nous proposons dans cette thèse d'utiliser une transmission vidéo à deux niveaux de priorité. Une des originalités de notre étude réside dans le choix des modes de transmission : flux haute priorité sur canal a débit constant (CBR) et flux basse priorité sur canal à débit variable (VBR). Ce système se distingue des autres méthodes (ARQ, FEC,) par sa capacité à garantir la réception des données vidéo de base, sans entrainer une augmentation inacceptable du débit et du délai de transmission, ni perdre de vue l'intérêt majeur de la transmission sur réseau ATM : le multiplexage statistique. L'innovation de ce travail consiste à quantifier les conséquences du choix d'un codage vidéo à deux niveaux de priorité en termes de qualité de service (QOS), d'allocation de ressources, de cout de transmission et de multiplexage statistique. Pour cela, nous avons dans un premier temps étudié une modélisation des flux de cellules sortant des codeurs MPEG-2. Sur la base du processus MMPP(2). Un modèle original, capable de prendre en considération les caractéristiques spatiales du contenu des images ainsi que les différents types d'image du codage MPEG-2 (i, p et b), est propose. L'étude comparative complété des deux modes de codage a deux niveaux de priorité retenus pour ce travail, le DP et le SNR-s, constitue la deuxième originalité de cette thèse. Nous avons pu mettre l'accent sur l'intérêt à transmettre en mode dp plutôt qu'en mode SNR-s, grâce à un flux haute priorité DP de débit plus faible et moins variable, et donc moins couteux. Une comparaison inédite des bandes passantes des codages en mode DP et SNR-s, par rapport au codage monocouche traditionnel, fait apparaitre une légère augmentation du débit total a allouer en transmission a deux niveaux, ce qui correspond au prix a payer en échange de la qualité de service supplémentaire. Nous nous sommes finalement intéressés au cout de transmission a partir de la tarification publiée par un operateur de télécommunications. Outre le fait que la grille de tarifs proposée est inadéquate avec un service vidéo de type grand public, nous nous sommes aperçus de l'inadaptation du rapport des couts du mode CBR sur le mode VBR.
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Machado, Elaine Alves Silva. "Ocorrência e fatores de risco de infecção de sítio cirúrgico em colecistectomia videolaparoscópica." Universidade de São Paulo, 2017. http://www.teses.usp.br/teses/disponiveis/22/22132/tde-29112017-194706/.
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A infecção de sítio cirúrgico (ISC) é uma complicação que pode acometer o paciente, acarretando incremento da mortalidade e morbidade, bem como aumento dos custos em saúde. A videocirurgia surgiu como opção menos invasiva de acesso à cavidade abdominal, reduzindo as taxas de ISC, mas nem mesmo a modernização gerada pela cirurgia minimamente invasiva conseguiu extinguir esse tipo de infecção. O presente estudo teve como objetivo geral analisar a ocorrência e os fatores de risco de infecção de sítio cirúrgico, em pacientes submetidos à colecistectomia videolaparoscópica. Trata-se de estudo descritivo exploratório conduzido em hospital de pequeno porte, localizado no sudoeste de Minas Gerais. A amostra foi composta por 118 pacientes. Para a coleta de dados, elaborou-se instrumento, o qual foi submetido à validação de face e conteúdo por estudiosos da área de conhecimento de enfermagem perioperatória. A coleta dos dados foi realizada no período de março a novembro de 2016 e, em três momentos, a saber: perioperatório, retorno ambulatorial e busca ativa fonada. Os dados foram coletados pelo pesquisador e um auxiliar de pesquisa devidamente treinados. A ocorrência de ISC foi de 5,9% (n=7), sendo todos os casos diagnosticados como infecção incisional superficial. As variáveis investigadas relacionadas ao paciente foram sexo, faixa etária, Índice de Massa Corporal, presença de doença crônica e classificação ASA. As variáveis estudadas relacionadas ao procedimento anestésico-cirúrgico foram tempo total de internação, porte cirúrgico, tempo de anestesia e tempo de cirurgia. Os resultados não apresentaram diferença estatisticamente entre as variáveis de interesse e a presença de ISC. Todos os casos de ISC foram diagnosticados, após a alta hospitalar, desses, seis pacientes (86%) tiveram o diagnóstico no retorno ambulatorial, e um paciente (14%) foi diagnosticado durante a busca ativa fonada. A condução do estudo oferece subsídios para a compreensão da problemática, no âmbito nacional. Além disso, gerou evidências para a reflexão dos profissionais de saúde em relação à subnotificação desse tipo de infecção em cirurgia minimamente invasiva, reforçando a necessidade de implantação de programa de vigilância pós-alta, nos serviços de saúdeSurgical site infection (SSI) is a complication that can affect the patient, leading to an increase in mortality and morbidity, as well as an increase in health costs. Video surgery emerged as a less invasive option for access to the abdominal cavity, reducing SSI rates; however, not even the improvement generated by minimally invasive surgery was enough to eliminate this type of infection. This study aimed to analyze the occurrence and risk factors of surgical site infection in patients submitted to laparoscopic cholecystectomy. It is an exploratory-descriptive study conducted in a small hospital, located in the southwest of Minas Gerais. The sample consisted of 118 patients. An instrument was developed for data collection, which was submitted to face and content validation by experts in perioperative nursing. Data collection was performed from March to November 2016 and, in three stages: perioperative, outpatient return and active phone search. Data were collected by the researcher and a properly trained research assistant. The occurrence of SSI was 5.9% (n=7), being all cases diagnosed as superficial incisional infection. The studied variables related to the patient were gender, age, Body Mass Index, presence of chronic disease and ASA classification. The studied variables related to the anesthetic surgical procedure were total length of hospitalization, surgical procedure size, time of anesthesia and time of surgery. The results did not show statistically difference between the variables of interest and the presence of SSI. All cases of SSI were diagnosed after patient discharge, and among them, six patients (86%) were diagnosed during outpatient return, and one patient (14%) was diagnosed during the active phone search. This study offers subsidies for understanding the problem at national level. In addition, it generated evidence for the reflection of health professionals regarding the underreporting of this type of infection in minimally invasive surgery, reinforcing the need to implement a post-discharge surveillance program in health services
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Thouvenin, Sandra Rose. "To Stop and Look: Richard Serra's Icelandic Sculpture Afangar and Related Notebook Drawings." Kent State University / OhioLINK, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=kent1437651095.
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Ben, Slama Romdhane. "Contribution à l'étude et au développement de pompes et capteurs solaires." Valenciennes, 1987. https://ged.uphf.fr/nuxeo/site/esupversions/837d0fce-7c31-4c4e-93a3-36786913daab.
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Etude et développement une pompe à eau solaire fiable peu couteuse pouvant être fabriquée aisément avec peu de moyens. Le principe est le pompage par le vide créé par la condensation de vapeur d'eau. En outre il est possible d'utiliser la pression créée lors du chauffage pour le transvasement de l'eau permettant l'exploitation de nappes phréatiques plus profondes. Amélioration du rendement des capteurs solaires à air. Expérimentation de différents types de capteurs solaires plans a 2 lames d'air comportant des chicanes de formes diverses.
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Lubnau, Anne. "Phénomène de récits de vie et communication intergénérationnelle : les sites institutionnels et non institutionnels des récits de vie intergénérationnels." Thesis, Bordeaux 3, 2015. http://www.theses.fr/2015BOR30038/document.
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Qu'est-ce qui prédispose le Portugal, le Brésil, le Québec, et l'Indiana aux USA, à mettre en place des sites institutionnels des récits de vie comme les musées de la personne, contrairement en France, où des initiatives de ce genre relèvent de la vie privée ? Nous nous interrogeons sur la force que peuvent revêtir ces récits de vie vidéos et sur le choix de ces pays de les podcaster : s’agit-il de redonner la parole à toutes les générations, les rendre plus visibles ou audibles, dans le but de transmettre, de laisser des traces pour la postérité ? Quelle est la teneur des ces traces, et qu’est-ce qui s’opère dans l’interaction entre générations ? Nous recherchons à podcaster et étudier les traces sémiotiques, sémantiques, sémiologiques des récits de vie issus de ce réseau de sites « Musée de la personne » de ces 4 pays. Nous considérons que les traces de la mémoire vivante des récits présents sur des supports numériques ou audiovisuels, constituent un édifice aussi matériel qu’un musée dans un espace donné. Le récit de vie traduirait une immémorialité, « un mouvement permanent entre temps présent et temps passé, des informations ou des événements passés et présents marquent le dialogue présent ». Nous sommes en présence de normes nouvelles, mais surtout en présence de paradigmes successifs ou de mouvements paradoxaux de recontextualisation et de reconfiguration symbolique, au fur et à mesure que ces récits de vie se transmettent d’un citoyen à un autre. Ces récits et « ces pratiques mémorielles sont très vivants chez les Anglais et les Australiens ». Il nous semble que les récits de vie peuvent participer à la formation du lien social entre générations, entre citoyens nationaux et non nationaux. Ce lien social doit s’inscrire dans l'attention et la responsabilité portée et partagée entre ascendants et descendants. Ce programme d'attention aux générations s'appelle la « neguentropie ». Il s'agirait d'un programme éthique et responsable de l'attention portée à autrui, basé sur la générosité.Tous ces dispositifs d'attention, ces récits de vie doivent s’inscrire dans une « noopolitique » de la santé publique aussi bien physique que mentale. Il s'agit de prendre garde « aux déficits attentionnels et aux troubles intergénérationnels ». Un « psychopouvoir » devrait être mis en place par nos gouvernements au service « d'une politique industrielle des technologies de l'esprit »What predisposes Portugal, Brazil, Quebec, and Indiana in the USA, to set up institutional sites of “life stories” on supports (media) videos (like virtual museums), unlike in France, where such initiative remains private life? We will try to focus on the strength of life stories, and we will try to understand why countries chose to podcast them. Actually, do they use life stories in order to hand over to the rising generation, and to make them more visible and audible, so that life stories are passing on and leave prints forever (to let posterity)? Besides, what is the content of these prints, and what do they occur to the generations? Also, what about the interaction between them? In fact, we will try to podcast and study semiotic, semantic and semiological prints of life stories that we can find on the following websites, called “Museum of the person" which is suitable for the four countries that we have previously mentioned. It seems that life stories prints found in digital and audiovisual media, are like a material building, as real as a museum in a given and real place. Moreover, we have to say that a life story is like a "permanent movement between the past and the present” that influences the present dialogue. We are facing with such new standards, especially with successive paradigms or paradoxical movements of recontextualization and symbolic reconfiguration, every time that a life story is told from a citizen to another. Life stories and memory passing down generation to generation, are very common to English and Australian people. It truly seems that life stories prints are part of a social link between all the generations, and also between national and non-national citizens. This important social link takes part of aspecific care/ attention to memories and their responsibility that are shared between ascendants and descendants. This care program is called "neguentropy". It is an ethical and responsible program based of the attention to others, and generosity. All this plan of actions, relying on the attention of life stories, should be part of a”physical and mental public noopolitic health program”. The aim is to face attention deficit disorder and intergenerational discord. Finally, a "psychopower" should be set up by our governments in order to serve an “industrial policy of spirit mind technology”
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Lancry, Matthieu. "Contribution à l'étude de méthodes de sensibilisation de fibres optiques de communication et mécanismes associés." Lille 1, 2004. https://ori-nuxeo.univ-lille1.fr/nuxeo/site/esupversions/ede850ab-f1c9-467d-9f5c-9ca2b64ac672.
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Sous l'effet d'une insolation lumineuse (en général ultraviolette), l'indice de réfraction de la plupart des verres de silice se modifie de façon permanente. Cet effet est désigné sous le nom de photosensibilité. Le phénomène se révèle intéressant pour les télécommunications optiques dans la mesure où il permet l'inscription de composants optiques passifs dans le coeur des fibres optiques ou dans des films planaires. Dans le cadre de ce travail de doctorat, nous avons réalisé un ensemble d'études sur la photosensibilité de verres germanosilicates sous l'action d'insolations réalisées à l'aide d'un laser à ArF ([lambda]p=193nm)ou d'un laser à KrF ([lambda]p=248nm). Nous avons étudié trois différentes méthodes de sensibilisation des verres germanosilicates : l'hydrogénation à haute pression et à température ambiante, l'hypersensibilisation UV (hydrogénation, insolation unifor:me et dégazage) ainsi que la méthode de chargement en hydroxyles (élévation thermique à 1000ʿC durant un court instant puis dégazage). D'une part, il s'agissait de comparer les trois méthodes de sensibilisation des fibres optiques germanosilicates en terme d'efficacité, de 'stabilité des procédés et des variations d'indice ainsi que des pertes créées vers 1,5 micron. D'autre part, une étude destinée à préciser les mécanismes de la sensibilisation et les origines des changements d'indice a été présentée dans ce mémoire. A cet effet, nous avons enregistré les spectres d'excès de pertes induits dans l'infrarouge et l'ultraviolet lors de l'insolation UV de lames de préforme ou de fibres germanosilicates sensibilisées.
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Buzz, Lu La. "The states and status of clay : material, metamorphic and metaphorical values." Thesis, University of Plymouth, 2018. http://hdl.handle.net/10026.1/11639.
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This doctoral project combines a performance-led practice with contextual research in order to demonstrate how arts practice can challenge historical perceptions of clay and enhance its material status. The core knowledge deduced from this research is that embodied performance transforms connectivity between artist and clay and produces a unified incarnation of both elements. Through the use of immersive research methods I gained insights which could not have been predicted - particularly that my experiential performances were a process of ‘clay becoming’ in which I ultimately became the clay. In terms of locality, the practice, comprising eight performance-led works and related documentation, focuses on the China Clay and Ball Clay of South West England. Traditionally in the arts, these materials are associated with ceramics, where through heating, clay becomes rigid and fixed. In contrast, my research investigates the textural fluidity and metamorphic potential of these clays in their raw state. The practice encompasses two interrelated groups of work; the In-breath and Out-breath. These terms are significant in three respects. Firstly they define two different modes and moments of practice. Secondly they refer to myself as a living component of these practices. Thirdly they reflect the cultural associations of clay as a metaphor for life. During the initial exploratory ‘In-breath’ phase of my practice, comprising four site-specific pieces, I engaged with clay at sites of historical relevance, building an expansive knowledge of my material. During the later ‘Out-breath’ phase, identification with site was relinquished. These works took place within neutral spaces, allowing the clay to be explored in relation to my body. The introduction of layering, where photographic elements of private clay rituals were situated within the context of a live performance, allowed a texturally dynamic and immersive experience to be created for both artist and viewer. By collecting and preserving clay traces from these live performances (e.g. foot and body prints) additional value was given to the embedded significance of the clay.
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Krupa, Frédérique. "Girl Games : gender, technology and design for women’s recruitment in Information and Communication Technology (ICT)?" Thesis, Paris 1, 2018. https://ecm.univ-paris1.fr/nuxeo/site/esupversions/dd3e6426-fd66-4db2-add5-56476ec75bf6.
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Cette thèse se concentre sur le genre, le design et la technologie à travers l'artefact des jeux vidéo - les produits de la culture d'ingénierie masculine, et le lien de genre entre ceux qui font les jeux vidéo (Production) et ceux qui les jouent (Réception). Ma recherche porte sur l'industrie du jeux vidéo consacré aux pré-adolescentes qui, il y a 20 ans, était le site de l'entreprenariat féministe espérant remédier au déséquilibre entre les sexes dans les TIC. Si la parité a été atteinte dans la consommation des médias, la production technologique reste délibérément une quête masculine. Cette étude constructiviste en trois phases commence par les préférences personnelles (MBTI) et l'orientation de rôles sexués (BSRI) des femmes dans le développement des jeux, en soulignant leur résistance aux stéréotypes de genre, et se termine par une étude ethnographique des enfants jouant à des jeux vidéo indépendants et non sexistes dans un programme extrascolaire à Paris. Utilisant la sémiotique pragmatique, cette thèse soutient que les croyances et habitudes des stéréotypes négatifs de genre et de technologie sont le principal obstacle à la diversité des genres dans les TIC - limitant le nombre de femmes désirant transgresser les normes de genre dans les professions masculines — et créant une prophétie auto-réalisatrice à travers la socialisation du genre par les parents qui réifient la croyance dans les compétences technologiques masculines tout en développant un accès et un encouragement technologiques inégal entre les sexes. La thèse se termine par de l'heuristique de conception pour la neutralité de genre dans les expériences numériques des enfantsThis dissertation focuses on gender, design and technology through the artifact of video games — technology products of masculine engineering culture, and the gendered link between those that make video games (Production) and those that play them (Reception). My research examines a sector of the video game industry devoted to pre-adolescent girls, which 20 years ago was the site of feminist entrepreneurship hoping to remedy the gender imbalance in ICT (Information and Communication Technology). While parity has been achieved in media consumption, technological production firmly remains a masculine pursuit. This three-phase constructivist study begins with the personality preferences (MBTI) and sex-role orientation (BSRI) of women in game development, highlighting their exceptional resilience to gender stereotypes, and concludes with an ethnographic study of children playing independent, gender-neutral video games at an afterschool program in Paris. Using pragmatic semiotic epistemology, this dissertation argues that the belief-habits of negative gender and technology stereotypes are the principal roadblock to gender diversity in ICT – limiting the number of women willing to transgress gender norms into masculine professions and creating a self-fulfilling prophecy through parents’ gender-socialization that reifies the belief in masculine technological passion and skill while developing unequal gendered technological access and encouragement. The dissertation concludes with strategies for gender-neutralizing technology, including design heuristics for gender neutrality in children’s digital experiences
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Kurtz, Matthew B. "What Comes After the Blues." Kent State University / OhioLINK, 2021. http://rave.ohiolink.edu/etdc/view?acc_num=kent1619717430532435.
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Duris, Maxime. "Conception et réalisation de filtre optique multicouche à grand nombre de couches minces dans le domaine spectral de 0,3 à 15 µm." Thesis, Rennes 1, 2020. https://ged.univ-rennes1.fr/nuxeo/site/esupversions/f003f6e9-b485-44df-92bc-46b0ed838e2f.
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Les filtres optiques à grand nombre de couches minces constituent un élément clé de la performance et de l’innovation des systèmes optiques. Les revêtements de surface dédiés à l’optique sont des vecteurs de recherche dans tous les secteurs industriels associés à l’optique. La conception et la réalisation des filtres optiques multicouches à grand nombre de couches minces opérant dans le moyen infrarouge de 2 µm à 15 µm sont la problématique de recherche de ces travaux de thèse. Dans cette thèse, l’accent a été mis sur l’étude, le déploiement, l’amélioration et l’optimisation des procédures de dépôt du Sulfure de Zinc (ZnS) et de Germanium (Ge). L’optimisation des constantes optiques du Germanium en fonction des paramètres de dépôt par la méthode des plans d’expériences est présentée et discutée. Un plan d'expérience a été utilisé pour étudier et optimiser les conditions de dépôt du Germanium. Ce plan d'expérience traitait 4 paramètres de dépôt : la vitesse de dépôt, le vide avant dépôt, la pression de dépôt et l'assistance ionique (IAD) Les résultats extraits du plan d’expérience comprennent les effets importants de la vitesse de dépôt, de l’assistance ionique de compactage et de leurs interactions, l’effet dissipatif du vide avant dépôt et de la pression de dépôt dans l'enceinte de dépôt sur l’énergie de croissance de la couche mince, et l’obtention d’un ensemble de conditions de dépôt optimisées pour réaliser des couches minces de Germanium avec un indice de réfraction le plus haut possible et un coefficient d’extinction le plus bas possible. Les mises en empilement des matériaux nous ont permis de réaliser plusieurs types de filtres optiques, des revêtements antireflets de 2 µm à 14 µm composés de 2 à 11 couches minces, un miroir à 10,6 µm en 9 couches minces ou bien un filtre dichroïque composé d'un miroir de 2 µm à 5 µm et d'un revêtement antireflet de 8 µm à 14 µm constitué de 29 couches minces. Nous avons pu étudier la fiabilité et la robustesse des couches minces des matériaux améliorés et optimisésOptical filters with a large number of thin films are key elements in the performance and innovation of optical systems. The surface coatings dedicated to optics are vectors of research in all the industrial sectors associated with optics. The design and fabrication of multi-layer optical filters with large number of thin layers with applications in the mid-Infrared spectral range (from 2 µm to 15 µm) are the research problem of this thesis work. In this thesis, the focus was placed on the study, deployment, improvement and optimization of the deposition procedures of Zinc Sulphide (ZnS) and Germanium (Ge). The optimization of the optical constants of Germanium according to the deposition parameters by the design of experiments method is presented and discussed. A design of experiments (DOE) was used to study and optimize Germanium’s deposition conditions, the experiment plan dealt with 4 deposition parameters: deposition speed, pre-deposition vacuum, deposition pressure and ion assisted support (IAD). The results extracted from the DOE include the significant effects of deposition rate, IAD and their interactions, the dissipative effect of pre-deposition vacuum and deposition pressure in the deposition chamber on the growth energy of the thin layer, and a set of deposition conditions optimized to achieve thin layers of Germanium with the highest possible refractive index and extinction coefficient. The stacking of Ge and ZnS thin layers enabled us to fabricate several types of optical filters namely an antireflective coatings from 2 µm to 14 µm composed of 2 to 11 thin layers, a 9 thin-layers mirror at 10,6 µm or a dichroic filter consisting of a 2 µm to 5 µm mirror and an 8 µm to 14 µm antireflective coating consisting of 29 thin-film. Furthermore, we were able to study the reliability and robustness of the thin layers of improved and optimized materials
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Mansour, Dana. "Pour une culture de la participation des publics : les stratégies médiatiques d’Al Jazeera. Étude sémiotique des vidéos promotionnelles et du site web participatif Sharek : Al Jazeera face à la guerre de Gaza (2009) et aux révolutions arabes (2011)." Thesis, Paris 2, 2018. http://www.theses.fr/2018PA020028/document.
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Dans le monde arabe comme partout dans le monde, le numéro d’utilisateurs des réseaux sociaux ne cesse de croître reléguant ainsi le vieux media au second plan. Ce nouveau media par son accessibilité, est devenu le nouveau lieu de pèlerinage où se rencontre tout chercheur de la vérité. Or, malgré l’absence d’une vraie crédibilité des institutions médiatiques arabes, Al-jazeera était la seule chaîne qui a su gagner la confiance des spectateurs et qui a réussi à regrouper autour d’elle des millions de fidèles arabophones. Durant les révolutions arabes, le quêteur de la vérité a été témoin d’une concurrence de taille entre ces deux sacrées plates-formes, imposés comme alternatif susceptible de satisfaire la soif de l’homme pour la liberté longuement absente dans le media tout comme en société. Cette étude a donc pour ambition d’étudier la rivalité et puis la réconciliation entre « vieux media » en l’occurrence la chaîne satellitaire et les nouveaux medias (les réseaux sociaux) durant le printemps arabe. Il s’agit également d’analyser l’analogie entre la révolution en terre arabe et celle en ligne et d’examiner le potentiel de chacun à provoquer un changement sociopolitique communThe co-production of information with the Arab viewer has always been the directive editorial line that distinguished the Qatari channel Al Jazeera since its creation in 1996. Over the years, the recipe has paid off, making Al Jazeera the most watched international news channel in the Arab world. The strategic choice of the channel to make the Arab spectator, long marginalized in the media, an ally is explained by a desire for legitimacy by the emir Hamad ben Khalifa al-Thani especially after the coup against his father in 1995. Nevertheless, cutting off from the old regime imposes substantial changes. With the first political debates on Al Jazeera, the status of the Arab viewer changes dramatically. They become actors and participate with their questions and comments at the cost of a simple phone call. But at the same time, Al Jazeera becomes the enemy of the Arab regimes. Over the years, the Qatari channel won the trust of many viewers, especially during its coverage of major crises in the Arab world, like the second Intifada in 2000 and the American invasion of Iraq in 2003. Through its media coverage from the ground in hot zones, it differentiates itself from other news channels. The year of 2011 was a major turning point in the history of the channel. From day one, Al Jazeera covered the rising demonstrations in the Arab countries. The declared war of autocratic regimes against Al Jazeera does not prevent it from covering stories. Aware of the contributions of digital media, the channel gives spectators the means to participate in the creation and circulation of information. The promotional videos of Al Jazeera are a concrete example. Throuh their short form which enables them to travel from one medium to another; they become an object of media activism. As for the digital platform Sharek, it shows how the channel involves the Arab spectator in the process of spreading and archiving information
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Brun-Dhaouadi, Dora. "De la construction à la vente du navire." Thesis, Paris 1, 2020. https://ecm.univ-paris1.fr/nuxeo/site/esupversions/c0f3bba9-1d8a-4323-8996-739a01aed770.
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La communauté maritime apparaît peuplée d'acteurs qui interviennent autour du navire mais aussi qui interagissent pour sa vente, sa future exploitation, et ses performances de navigation. Ces opérateurs sont stimulés par les enjeux logistiques et financiers, d'où cette diversité des recours qui démontre la complexité des liens concernant les contrats attachés au navire, depuis sa construction, sa vente jusqu'à sa mise en exploitation. Le constructeur naval est l'opérateur clé dans ce domaine. Les obligations du chantier naval, déjà lourdement obéré par le régime procédural de la garantie des vices cachés, sont multiples et contraignantes si bien qu'il est tenu de garantir la navigabilité du navire depuis sa recette jusqu'à son exploitation. La subtilité du régime juridique du navire réside dans son statut réel si particulier qui emprunte des règles issues à la fois du droit spécial et du droit commun si bien que le cadre contractuel révèle le particularisme du droit maritime. Ainsi, le navire représente une opération de grande envergure car il fait l'objet de grands enjeux économiques et financiers. L'on observe que le navire est plus sophistiqué, plus onéreux, et par conséquent, les opérations qui en découlent sont sources de litiges fastidieux qui appellent à des mécanismes procéduraux complexes dont les juridictions étatiques et arbitrales s'efforcent de maîtriserThe maritime community appears to be populated by actors who are involved in the ship field while interacting for its sale, its future performance in operation. These operators are given for logistical and financial challenges, hence this diversity of lawsuits which reveal the complexity of the relationships regarding the contracts linked to the ship, from its construction, its sale to its operation implementation. The shipbuilder is the key operator in this field. The obligations of the shipyard, so far constrained by the guarantee of the latent defect legal framework, are numerous and tough so well that the shipbuilder is deemed to ensure the vessel seaworthiness from its delivery to its performance in operation. The cleverness of the ship's legal regime lies in its very special status, which borrows rules derived from bath special and common French law, so that the contractual framework reveals the particularism of maritime law. Thus, the ship represents a large-scale operation because it’s subject to major financial challenges and spin-offs. That’s obvious that the vessel is more sophisticated, more expensive, and therefore, the resulting operations are a source of cumbersome litigation which are solved by complex procedural mechanisms that State and Arbitration courts strive to control
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Khokhar, Muhammad Jawad. "Modélisation de la qualité d'expérience de la vidéo streaming dans l'internet par expérimentation contrôlée et apprentissage machine." Thesis, Université Côte d'Azur (ComUE), 2019. http://www.theses.fr/2019AZUR4067.
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Le streaming vidéo est l'élément dominant au trafic Internet actuel. En conséquence, l'estimation de la qualité d'expérience (QoE) pour le streaming vidéo est de plus en plus importante pour les opérateurs réseau. La qualité d'expérience (QoE) de la diffusion vidéo sur Internet est directement liée aux conditions du réseau (par exemple, bande passante, délai) également appelée qualité de service (QoS). Cette relation entre QoS et QoE motive l'utilisation de l'apprentissage automatique supervisé pour établir des modèles reliant QoS à QoE. La QoS du réseau peut être mesurée activement en dehors du plan de données de l'application (outband) ou de manière passive à partir du trafic vidéo (inband). Ces deux types de qualité de service correspondent à deux scénarios d'utilisation différents : la prévision et la surveillance. Dans cette thèse, nous examinons les défis associés à la modélisation de la QoE à partir de la QoS réseau, à savoir 1) le coût élevé de la phase expérimentale, et 2) la considération de la grande diversité du contenu vidéo et du chiffrement déployé. Premièrement, la modélisation de la QoE par expérimentation contrôlée constitue un défi, les dimensions d'espace d'expérimentations ainsi que le temps non négligeable de chaque expérience rend cette modélisation plus complexe. L'approche classique consiste à expérimenter avec des échantillons (de qualité de service), échantillonnés de manière uniforme dans tout l'espace expérimental. Cependant, un échantillonnage uniforme peut entraîner une similarité significative au niveau des labels, ce qui entraine une augmentation du coût sans gain en précision du modèle. Pour résoudre ce problème, nous recommandons d'utiliser apprentissage actif pour réduire le nombre d'expériences sans affecter la précision. Nous examinons le cas de la modélisation QoE sur YouTube et montrons que l'échantillonnage actif fournit un gain significatif par rapport à l'échantillonnage uniforme en termes d'augmentation de la précision de la modélisation en moins d'expériences. Nous évaluons ensuite notre approche avec des ensembles de données synthétiques et montrons que le gain dépend de la complexité de l'espace expérimental. Dans l'ensemble, nous présentons une approche générale d'échantillonnage qui peut être utilisée dans n'importe quel scénario de modélisation QoS-QoE, à condition que la fonctionnalité de QoS en entrée soit entièrement contrôlable. Deuxièmement, prévoir la qualité de l'expérience de la vidéo avec précision s'avère difficile, d'une part les vidéos des fournisseurs de contenu actuels varient énormément, des vidéos sportives rapides aux vidéos éducatives statiques. De plus, le trafic vidéo actuel est crypté, ce qui signifie que les opérateurs de réseau ont une visibilité réduite sur le trafic vidéo, ce qui rend la surveillance de la QoE plus complexe. Face à ces défis, nous développons des modèles afin de prévoir ainsi que surveiller avec précision la qualité de l'expérience vidéo. Pour le scénario de prévision QoE, nous construisons un indicateur QoE appelé YouScore qui prédit le pourcentage de vidéos pouvant être lues sans interruption en fonction de l'état du réseau sous-jacent. En ce qui concerne la surveillance QoE, nous estimons la QoE à l'aide des fonctionnalités de qualité de service inband obtenues à partir du trafic vidéo crypté. En conclusion, pour les deux scénarios (prévision et surveillance), nous soulignons l'importance d'utiliser des fonctionnalités qui caractérisent le contenu vidéo afin de pouvoir améliorer la précision des modèlesVideo streaming is the dominant contributor of today's Internet traffic. Consequently, estimating Quality of Experience (QoE) for video streaming is of paramount importance for network operators. The QoE of video streaming is directly dependent on the network conditions (e.g., bandwidth, delay, packet loss rate) referred to as the network Quality of Service (QoS). This inherent relationship between the QoS and the QoE motivates the use of supervised Machine Learning (ML) to build models that map the network QoS to the video QoE. In most ML works on QoE modeling, the training data is usually gathered in the wild by crowdsourcing or generated inside the service provider networks. However, such data is not easily accessible to the general research community. Consequently, the training data if not available beforehand, needs to be built up by controlled experimentation. Here, the target application is run under emulated network environments to build models that predict video QoE from network QoS. The network QoS can be actively measured outside the data plane of the application (outband), or measured passively from the video traffic (inband). These two distinct types of QoS correspond to the use cases of QoE forecasting (from end user devices) and QoE monitoring (from within the networks). In this thesis, we consider the challenges associated with network QoS-QoE modeling, which are 1) the large training cost of QoE modeling by controlled experimentation, and 2) the accurate prediction of QoE considering the large diversity of video contents and the encryption deployed by today's content providers. Firstly, QoE modeling by controlled experimentation is challenging due to the high training cost involved as each experiment usually consumes some non-negligible time to complete and the experimental space to cover is large (power the number of QoS features). The conventional approach is to experiment with QoS samples uniformly sampled in the entire experimental space. However, uniform sampling can result in significant similarity in the output labels, which increases the training cost while not providing much gain in the model accuracy. To tackle this problem, we advocate the use of active learning to reduce the number of experiments while not impacting accuracy. We consider the case of YouTube QoE modeling and show that active sampling provides a significant gain over uniform sampling in terms of achieving higher modeling accuracy with fewer experiments. We further evaluate our approach with synthetic datasets and show that the gain is dependent on the complexity of the experimental space. Overall, we present a sampling approach that is general and can be used in any QoSQoE modeling scenario provided that the input QoS features are fully controllable. Secondly, accurate prediction of QoE of video streaming can be challenging as videos offered by today's content providers vary significantly from fast motion sports videos to static lectures. On top of that, today's video traffic is encrypted, which means that network operators have little visibility into the video traffic making QoE monitoring difficult. Considering these challenges, we devise models that aim at accurate forecasting and monitoring of video QoE. For the scenario of QoE forecasting, we build a QoE indicator called YouScore that quantifies the percentage of videos in the catalog of a content provider that may play out smoothly (without interruptions) for a given outband network QoS. For the QoE monitoring scenario, we estimate the QoE using the inband QoS features obtained from the encrypted video traffic. Overall, for both scenarios (forecasting and monitoring), we highlight the importance of using features that characterize the video content to improve the accuracy of QoE modeling
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Song, Le. "Multimodal Interactional Practices in Live Streams on Twitter." Electronic Thesis or Diss., Institut polytechnique de Paris, 2024. http://www.theses.fr/2024IPPAT019.
Full textAbstract:
En tant que forme émergente d'interaction médiatisée, la diffusion en direct (live streaming) est devenue une pratique en pleine expansion qui combine les caractéristiques techniques et interactionnelles de l'interaction vidéo-médiatisée et du chat multi-participants. Le live streaming à l'aide d'appareils mobiles sur plusieurs plateformes est donc une pratique dans laquelle les diffuseurs (streamers) et les spectateurs interagissent sous des formes hautement asymétriques: l'affichage vidéo du diffuseur et le texte écrit du spectateur. Cette thèse de doctorat s'intéresse au live streaming en tant que phénomène interactionnel d'un point de vue séquentiel. S'appuyant sur des données vidéo enregistrées d'activités advenant naturellement dans des live streams orientés vers la vie quotidienne sur Twitter (maintenant ‘X') et sur l'ethnométhodologie et l'analyse conversationnelle (EMCA) comme perspective théorique et méthodologique, la thèse explore comment l'utilisation de multiples ressources (par exemple, parlées, écrites et corporelles), ainsi que la manipulation des ‘affordances' des appareils permettent de produire les cadres de participation propres aux live streams et l'accomplissement de différentes actions conjointes de manière séquentielle. La dissertation se compose de quatre articles de recherche principaux, traitant quatre phénomènes interactionnels caractéristiques des live streams. Le premier analyse les séquences d'ouverture des live streams. Contrairement aux conversations téléphoniques et leur séquence ‘canonique' d'ouverture, les ouvertures de live streams apparaissent plus variables, avec de multiples cadres de participation stratifiés, bien qu'il y ait généralement une phase d'installation reconnaissable où l'activité de diffusion commence. La thèse identifie des préoccupations interactionnelles spécifiques aux ouvertures, à savoir l'attente d'un public adéquat, par les streamers, la manière dont ceux-ci gèrent les interactions avec le public à la fois dans son ensemble, et de manière individuelle dans le cadre d'une relation invité/hôte, et les préoccupations affichées par les participants concernant l'intelligibilité immédiate du stream. L'article II discute de la manière dont les diffuseurs et les spectateurs démontrent attention et engagement en formulant ce que les streams rendent remarquables. Il examine ainsi comment les streamers et les spectateurs produisent des des séquences initiées par des remarques (noticings), et comment l'affinité particulière des live streams avec cette pratique à la fois attentionnelle et interactionnelle peut conduire à une 'effervescence attentionnelle' caractéristique. L'article III inspecte l'activité de dégustation dans le live streaming, où la dégustation est accomplie comme un processus interactif et multimodal qui combine l'expérience sensorielle individuelle avec une dimension publique, et intersubjective. L'article IV enquête les séquences de clôture dans le live streaming. Nous montrons comment les participants s'y orientent vers l'organisation des clôtures caractéristique de la conversation ordinaire, mais d'une manière très sensible aux affordances des diffusions vidéo en direct. La thèse fournit donc une analyse systématique des propriétés interactionnelles les plus caractéristiques du live streamingAs an emerging form of mediated interaction, live streaming has become a rapidly growing practice that combines the technical and interactional features of video-mediated interaction and multi-party chat. Live streaming with mobile devices on multiple platforms has thus been a practice in which streamers and viewers interact in highly asymmetric forms—the streamer's video display and the viewer's written text. This doctoral dissertation focuses on live streams as interactional phenomena from a sequential perspective. Drawing on video-recorded data from ordinary users' naturally unfolding activities in daily life-oriented live streams on Twitter (now ‘X') and taking ethnomethodology and conversation analysis (EMCA) as its theoretical and methodological perspective, the thesis explores how the use of multiple (e.g., spoken, written and embodied) resources, as well as the manipulation of affordance of the devices in establishing the participation framework of live streaming interactions and achieving different joint actions stepwise. The dissertation consists of four main research articles, each focusing on a typical interactional phenomenon in live streaming. All of the articles have been published or are under review. Article I investigates the openings of live streaming. Unlike phone conversations with a canonical opening sequence, live stream openings appear more variable, with laminated participation frames, although there is usually a recognizable "installation" phase where the stream activity begins. We also identified interactional concerns in the opening, that is, the streamers' wait for an adequate audience, their collective and individual management of viewers within a guest/host relationship, and the concern of participants regarding the immediate intelligibility of the stream. Article II discusses how streamers and viewers manage attention and engagement through noticing-based actions. It looks at how streamers and viewers produce noticing sequences and noticing-based sequences, and how the orientation towards noticing may lead to a distinctive form of ‘noticing effervescence.' Article III inspects the activity of tasting in live streaming, re-examining tasting in this particular ecology as an interactive process that combines individual sensory experience with a public, witnessable, and intersubjective dimension. Article IV investigates the organization of closing sequences in live streaming. It shows that while participants can be seen to orient to the sequential organization of closings in ordinary conversation, they do so in a way that is particularly sensitive to the affordances of live video streams. The thesis thus provides a systematic analysis of the most characteristic interactional properties of live streaming
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Abidi, Soufien. "Les nοuveaux médias d'infοrmatiοn sur les RSΝ. Le cas des pure-players en Τunisie : Le cas des pure-players en Τunisie." Electronic Thesis or Diss., Normandie, 2024. http://www.theses.fr/2024NORMLH06.
Full textAbstract:
Notre recherche s’inscrit dans le contexte dynamique des médias numériques, où l’évolution constante de la production de l’information est une réalité incontournable. Dans ce paysage en mutation, les pure players d’information émergent comme de nouveaux acteurs médiatiques, proposant des contenus caractérisés par des formats et des styles narratifs hybrides qui repoussent les frontières traditionnelles de la production de l’information. Notre thèse se concentre spécifiquement sur l’un de ces acteurs, Faza.tn, un pure player tunisien 100% vidéo et 100% réseaux sociaux que nous choisissons comme cas d’étude pertinent dans ce phénomène médiatique particulier. Afin d’explorer en profondeur les spécificités distinctives de ces contenus tant sur le fond que la forme, nous avons mis en place une méthodologie de recherche combinant trois approches complémentaires. Premièrement, l’analyse quantitative nous permet d’obtenir une compréhension globale de la stratégie éditoriale pour les thèmes des sujets choisis, et les stratégies narratives marqués par une récurrence, ainsi que de la détermination des caractéristiques de forme. Deuxièmement, l’analyse de contenu nous plonge dans le décryptage des orientations éditoriales. Enfin, les entretiens semi-directifs nous permettent d’explorer les politiques éditoriales et les motivations au sein de Faza.tn. Notre objectif principal est d’évaluer dans quelle mesure ces contenus s’adaptent au journalisme mobileOur research is situated in the dynamic context of digital media, where the constant evolution of information production is an undeniable reality. In this changing landscape, pure players in information emerge as new media players, offering content characterized by hybrid formats and narrative styles that push the traditional boundaries of information production. Our thesis specifically focuses on one of these players, Faza.tn, a Tunisian pure player that is 100% video and 100% social media, which we select as a relevant case study in this particular media phenomenon. In order to delve into the distinctive characteristics of these contents in both substance and form, we’ve employed a research methodology that integrates three complementary approaches. Firstly, quantitative analysis allows us to gain a thorough understanding of the editorial strategy regarding selected topics, narrative patterns marked by repetition, and the identification of form attributes. Secondly, content analysis delves into unraveling editorial orientations. Lastly, semi-structured interviews afford us the opportunity to investigate editorial policies and motivations within Faza.tn. Our primary goal is to evaluate how well these contents align with mobile journalism
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Lee, Cheng-Che, and 李正哲. "Bed Site Health Care Video-Phone System." Thesis, 2012. http://ndltd.ncl.edu.tw/handle/53073791728583263451.
Full textAbstract:
碩士東海大學
電機工程學系
100
In recent years, the aging problem has become a very important issue to many developed countries. With the advances in Internet and technology, it’s a trend to combine the medical assistance with technology. Therefore, we invent this system “Bed Site Health Care Video Phone System.” We expect to increase the efficiency of medical process through our system. This system includes three functions. First, patients can have a direct talk with medical workers. Considering patients’ privacy, the design of the device makes the camera lens hidden unless patients press the nursing call. The second function is patients’ family and friends can have a remote video visit instead of present visit. Third, it can detect, record and analyze patients’ temperature, blood pressure, heart beat.