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[pt] Nesta tese é apresentada uma arquitetura altamente escalável para storytelling interativo em massa baseado em streams de vídeo. A arquitetura proposta pode suportar diferentes demandas para interatividade, geração e visualização de histórias em ambientes de televisão digital, que inclui set-top boxes de TV, tablets, smartphones e computadores. Nesta arquitetura, a mesma história se adapta ao aparelho do espectador em termos de renderização e processo de interface automaticamente. Também é apresentado um modelo para compartilhar histórias interativas em massa. Além disso, o sistema proposto preserva a coerência lógica da história que se desenrola enquanto a mantém interativa. / [en] In this thesis we present a highly scalable architecture for massive multi-user interactive storytelling systems based on video streams. The proposed architecture can support different demands for interactivity, generation, and visualization of stories in digital television environments, which include TV set-top boxes, tablets, smartphones, and computers. In this architecture, the same story adapts itself to the spectator s device in terms of rendering and interface processes automatically. Also a model for sharing massive interactive stories is presented. Moreover, the proposed system preserves the logical coherence of the story that unfolds while keeping it interactive.

With the increase in bandwidth, more widespread distribution of media, and increased capability of mobile devices, multimedia streaming has not only become feasible, but more economical in terms of space occupied by the media file and the costs involved in attaining it. Although much attention has been paid to peer to peer media streaming over the Internet using HTTP and RTSP, little research has focussed on the use of the Bluetooth protocol for streaming audio and video between mobile devices. This project investigates the feasibility of Bluetooth as a protocol for audio and video streaming between mobile phones using the J2ME platform, through the analysis of Bluetooth protocols, media formats, optimum packet sizes, and the effects of distance on transfer speed. A comparison was made between RFCOMM and L2CAP to determine which protocol could support the fastest transfer speed between two mobile devices. The L2CAP protocol proved to be the most suitable, providing average transfer rates of 136.17 KBps. Using this protocol a second experiment was undertaken to determine the most suitable media format for streaming in terms of: file size, bandwidth usage, quality, and ease of implementation. Out of the eight media formats investigated, the MP3 format provided the smallest file size, smallest bandwidth usage, best quality and highest ease of implementation. Another experiment was conducted to determine the optimum packet size for transfer between devices. A tradeoff was found between packet size and the quality of the sound file, with highest transfer rates being recorded with the MTU size of 668 bytes (136.58 KBps). The class of Bluetooth transmitter typically used in mobile devices (class 2) is considered a weak signal and is adversely affected by distance. As such, the final investigation that was undertaken was aimed at determining the effects of distance on audio streaming and playback. As can be expected, when devices were situated close to each other, the transfer speeds obtained were higher than when devices were far apart. Readings were taken at varying distances (1-15 metres), with erratic transfer speeds observed from 7 metres onwards. This research showed that audio streaming on the J2ME platform is feasible, however using the currently available class of Bluetooth transmitter, video streaming is not feasible. Video files were only playable once the entire media file had been transferred.

Orientador: Prof. Dr. Carlos Alberto Kamienski / Dissertação (mestrado) - Universidade Federal do ABC, Programa de Pós-Graduação em Engenharia da Informação, 2016. / Atualmente é comum as pessoas se conectarem à Internet em lugares públicos como praças, parques e bibliotecas. Algumas cidades oferecem conexão gratuita por WiFi, onde os usuários utilizam a Internet para diversas finalidades, como buscar informações, trocar mensagens e assistir a mídias digitais. A abordagem deste trabalho é a utilização de streaming de vídeo em praças digitais distribuídas pelas diversas regiões da cidade de São Paulo. Foram realizadas análises de desempenho do serviço prestado à comunidade nas cento e vinte praças do programa "WiFi Livre SP", no período de um ano. Para isso, foram utilizadas métricas que avaliam tanto a Qualidade de Experiência (QoE) do usuário, como a Qualidade de Serviço (QoS) da rede. Como resultado, obteve-se uma nova ferramenta de avaliação da Qualidade de Experiência dos usuários em transmissões de streaming de vídeo, bem como as características das praças em relação aos dados analisados, os quais mostram que, para diferentes praças, dias e níveis de qualidade de vídeo, na maioria das vezes, o uso é satisfatório para determinados fins. / Currently it is common for people to connect to the Internet in public places such as squares, parks and libraries. Some cities offer free connection by WiFi, where users use the Internet for various purposes, such as searching for information, exchange messages and watch digital media. The approach of this work is the use of video streaming in digital squares distributed among different regions of São Paulo. Performance tests of this service to the community were carried out in the 120 squares belonging to the "WiFi Livre SP program" in one year. For this we used metrics that assess both the Quality of Experience (QoE) of the user, such as Quality of Service (QoS) network. As a result we obtained a new evaluation tool of Quality of Experience of users in streaming videos, and the characteristics of the squares on the data analyzed which show that for different places, days and levels of video quality, in most of the time the use is satisfactory for particular purposes.

Pendant des décennies, la France a imposé des quotas pour la musique francophone. Les stations de radio doivent réserver un pourcentage minimal de pièces musicales pour les chansons de langue française depuis 1996. Le développement des services de diffusion en continu, sans quotas, a changé notre façon d'écouter de la musique et pose un nouveau défi aux organismes de réglementation. L'applicabilité des quotas est de plus en plus difficile dans l'industrie de la radiodiffusion et pose la question du désavantage concurrentiel. Dans cette thèse, j'essaie de répondre à trois questions principales sur le thème de la consommation de musique dans cet écosystème en mutation. Dans un premier temps, j'examine empiriquement les réponses stratégiques des radios françaises aux quotas de musique francophone. Les stations respectent-elles les quotas? L'audience réalisée pour la musique francophone est-elle inférieure à ce qu'elle serait en l'absence de ces réponses stratégiques? Pour répondre à ces questions, j'utilise des données détaillées sur les listes de lecture des principales stations de radio en France pour montrer que les stations ont une certaine latitude pour ajuster leurs playlists soumises aux contraintes de quotas. Deuxièmement, je construis un ensemble de données pour fournir des preuves descriptives sur les services de radio et de streaming. Ce sont des modèles économiques entièrement différents et ils ne sont pas comparables sans ajuster l'ensemble de données pour refléter les différences. Afin de comparer le nombre de titres musicaux sur les stations de radio avec le nombre de flux sur les services de streaming, je développe une méthodologie pour combiner les données radio avec les données en streaming en France en 2016. Troisièmement, en utilisant cette nouvelle base de données, la variété des motifs et de la musique sur les services de streaming se compare à celle de la radio. Je fournis également des preuves empiriques sur les ex ternalités de consommation des deux marchés. / For decades, France has imposed quotas for Francophone music. Radio stations need to reserve a minimum percentage of total song plays for French-language songs since 1996. The development of streaming services, which faces no quotas, has changed how we listen to music and poses a new challenge to regulators. The applicability of quotas is increasingly difficult in the radio broadcasting industry and raises the question of competitive disadvantage. In this thesis, I try to answer three main issues on the topic of music consumption in this changing ecosystem. First, I empirically examine the strategic responses of French radio stations to quotas for Francophone music. Do stations comply with the quotas? Is the realized audience for Francophone music lower than it would be in the absence of these strategic responses? To answer these questions, I use detailed data on the playlists of major radio stations in France to show that stations have some scope for adjusting their playlists subject to the quota constraints. Second, I build a dataset to provide some descriptive evidence on radio and streaming services. These are entirely different economic models, and are not comparable without adjusting the dataset to reflect the differences. In order to compare the audience number of music titles on radio stations with the number of streams on streaming services, I develop a methodology to combine radio data with streaming data in France in 2016. Third, using this novel dataset, I look at music consumption pattern and music variety on streaming services compares to that of radio. I also provide empirical evidence on the consumption externalities of both markets.

Avsikten med uppsatsen är att ta reda på om det skapats ett nytt radiolyssnarmönster i och med att Sveriges Radios (SR) erbjuder tjänsten on demandradio, det vill säga möjlighet att lyssna på radioprogram som redan har sänts på vanlig radio eller webbradio. John Fiske Kommunikations teorier har använts samt Walter Benjamin teorier som behandlar förändringar som sker vid reproduktion. Historiska teorier av Marshall McLuhan och Tony Schwartz har även använts. Författarnas metod består av tre delar där en jämförelse genomförts mellan olika sekundära data från SR, Radioundersökningar AB (RUAB), Nordiskt informationscenter för medie- och kommunikationsforskning (Nordicom), British Broadcasting Corporation (BBC) samt Radio Joint Audience Research Limited (RAJAR). Därefter har insamling av kvantitativa data gjorts via enkät som publicerats på SR:s hemsida samt via utskick till en referensgrupp. Författarna har gjort längre telefonintervjuer om cirka 35-45 minuter vilka spelats in och delvis transkriberats för att få in data med mer kvalitativ tyngd. Resultaten från enkäterna och intervjuerna pekar på att det finns ett nytt aktivt sätt att lyssna på radio i och med att man använder sig av on demandradiotjänsten. Man lyssnar när man har tid, man lyssnar när man missat något och man lyssnar när man vill höra ett program ännu en gång. Det är svårt att se ifall tiden för lyssnandet har ändrats, men tidpunkten för att lyssna på program som kräver mer uppmärksamhet verkar enligt telefonintervjuerna ha förflyttats till kvällstid när det för lyssnaren finns en ledig ”lucka” i tiden att lyssna på on demandradio. De siffror och speciellt den ökning i dessa siffror som BBC presenterar när det gäller on demandradiolyssnare visar på att denna ökning sannolikt kommer att ske även här i Sverige när folk upptäcker tjänsten. / The aim of the thesis is to study if new radio listening patterns have been created since Swedish public radio Sveriges Radio (SR) began offering radio repeats on demand via its website. Communication theories written by John Fiske have been used and theories by Walter Benjamin concerning how things change when reproduced. Marshall McLuhan and Tony Schwartz historic theories have also been utilized. The method used has been divided into three sections, where a comparison has been made between various secondary data from SR, Radioundersökningar AB (RUAB), the Nordic Information Center for Media and Communication Research (NORDICOM), the British Broadcasting Corporation (BBC) and Radio Joint Audience Research Limited (RAJAR). Quantitative data was collected via a questionnaire that was published on the SR website and through emailing the questionnaire to a reference group. The authors have carried out 35-45 minute telephone interviews which were recorded and partly transcribed to collect more qualitative data. Results from the questionnaires and interviews suggest that listeners to on demand radio services use a new, more active way of listening to the radio. People listen to on demand radio when they have time, listen when they have missed something in a programme, or choose to listen to a programme again. It is however difficult to see if the time for listening has changed, but the time for listening to radio programmes that require more concentration seems to have moved to evenings, and when listeners have an available “window” for concentrated on demand radio listening. It is nevertheless clear from the BBC figures and the growth in on demand radio listening at the BBC that this growth is also likely to take place in Sweden once the public becomes more aware of the availability of this service.

Les travaux de recherche du présent projet se situent dans le contexte général de l'optimisation de la technique de sono-thrombolyse (destruction d'un caillot sanguin ou d'un thrombus par cavitation ultrasonore). En effet, certes cette technique a plusieurs avantages par rapport à la solution chirurgicale, mais elle présente des limitations qui sont principalement le risque de libération de fragments du thrombus, susceptibles d'engendrer l'embolie pulmonaire. Face à ces limites actuelles que de la technique de sono-thrombolyse, s'est imposée la nécessité de pousser plus loin les recherches pour mieux comprendre les mécanismes qui la régissent. D'où le projet de la présente thèse qui s'intéresse plus particulièrement aux écoulements générés lors de l'application des ultrasons focalisés dans un liquide. L'objet du présent travail consiste à étudier minutieusement les phénomènes hydrodynamiques et acoustiques, en particulier le streaming acoustique du fluide et la force de radiation ultrasonore agissant sur les particules solides. Cela permettra d'obtenir une connaissance profonde des phénomènes hydrodynamiques se produisant lors de l'application des HIFU dans un milieu liquide chargé de particules.La technique optique de PIV a été adoptée pour mesurer l'écoulement du fluide ainsi que des particules solides. Ceci a permis de caractériser le streaming acoustique induit par la propagation des ultrasons focalisés dans un milieu liquide infini, de le comparer à un écoulement classique de type jet circulaire libre, et de déterminer un diamètre critique au-dessus du quel l'écoulement des particules solides sphériques dans un liquide est dominée par la force de radiation ultrasonore plutôt que par l'entrainement du streaming acoustique. Comme approche numérique, un outil de simulation CFD a été utilisé afin de modéliser le même écoulement de streaming en question et afin de comparer les résultats numériques avec les résultats expérimentaux obtenus / The research work of this project is provided in the context of sono-thrombolysis technique optimization (blood clot or thrombus destruction by ultrasonic cavitation). Indeed, although this technique has several advantages over the surgical solution, but it has limitations that are mainly the risk of thrombus fragments releasing in the circulation, likely to induce pulmonary embolism.In view of these sono-thrombolysis technique current limitations, it has become necessary to carry out further research to better understand the mechanisms that govern it. Hence, comes the project of the present thesis, which is particularly interested in the flows generated by the application of focused ultrasound in a liquid. The purpose of the present work is to accurately study the hydrodynamic and acoustic phenomena, in particular the fluid acoustic streaming and the ultrasound radiation force acting on solid particles. This would provide a deep understanding of the hydrodynamic phenomena occurring during HIFU (High Intensity Focused Ultrasound) application in a liquid medium with particles.Particle Image Velocimetry (PIV) optical technique has been adopted to measure the fluid flow as well as solid particles flow. This allowed us to characterize the focused ultrasound induced acoustic streaming in an infinite liquid medium, to compare it with a conventional circular free jet flow, and to determine a critical diameter above which solid spherical particles flow in a liquid is dominated by the radiation force rather than the acoustic streaming drag force. As a numerical approach, a CFD (Computational Fluid Dynamics) simulation tool was used to model the same streaming flow and to compare the numerical results with the experimental obtained ones

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / With the popularization of streaming in the music industry, new actors and models of production emerge and strengthen the idea of excluding world record companies from stages such as recording and distribution of music. This research analyzes two musical joints related to streaming that consolidate the hypothesis of weakening of these companies: the production of songs made by Spotify and the intermediation of the aggregating companies in the distribution of digital music. However, major record companies, also known as majors, still hold a hegemonic position and seek alternatives to remain profitable in this environment. On other hand, the insertion of streaming into the production chain of music is a phenomenon in development that serves the majors and artists considered independent. To understand the growth of streaming as a trend for the consumption of music on the Internet, it was necessary to carry out a literature review and an analysis of the reports and documents published by Pro-Música Brasil in the last ten years. Interviews with music professionals were also conducted with the objective of identifying new relationships with music in the digital scene. / Com a popularização do streaming na indústria fonográfica, novos atores e modelos de produção surgem e fortalecem a ideia de exclusão das gravadoras mundiais de etapas como gravação e distribuição de música. Esta pesquisa analisa duas articulações musicais relacionadas ao streaming que fortalecem a hipótese de enfraquecimento dessas empresas: a produção de músicas realizadas pelo Spotify e a intermediação das empresas agregadoras na distribuição de música digital. Porém, as grandes gravadoras, também conhecidas como majors, ainda sustentam uma posição hegemônica e buscam alternativas de se manterem rentáveis nesse meio. Dessa forma, a inserção do streaming na cadeia produtiva de música é um fenômeno em desenvolvimento que atende às majors e a artistas considerados independentes. Para entender o crescimento do streaming como tendência para o consumo de música na internet, foi necessário realizar uma revisão de literatura e uma análise dos relatórios e documentos divulgados pela Pró-Música Brasil nos últimos dez anos. Entrevistas com profissionais da música também foram realizadas com o objetivo de identificar novas relações com a música no cenário digital. / São Cristóvão, SE

Submitted by Renata Lopes (renatasil82@gmail.com) on 2016-05-17T12:01:58Z No. of bitstreams: 1 wagnerdealmeidajunior.pdf: 2594589 bytes, checksum: 9b2a2375eb8725cfda2a8aabadd86f22 (MD5) / Approved for entry into archive by Adriana Oliveira (adriana.oliveira@ufjf.edu.br) on 2016-06-28T14:01:42Z (GMT) No. of bitstreams: 1 wagnerdealmeidajunior.pdf: 2594589 bytes, checksum: 9b2a2375eb8725cfda2a8aabadd86f22 (MD5) / Made available in DSpace on 2016-06-28T14:01:42Z (GMT). No. of bitstreams: 1 wagnerdealmeidajunior.pdf: 2594589 bytes, checksum: 9b2a2375eb8725cfda2a8aabadd86f22 (MD5) Previous issue date: 2015-09-04 / A transmissão de conteúdo de mídia pela Internet é uma tendência que vem crescendo atualmente. Especialmente, o cenário de transmissão de vídeo sob demanda (VoD) já é bastante consolidado. Um novo desafio que surge é a transmissão de vídeo ao vivo, especialmente de conteúdo capaz de atrair um grande número de espectadores como eventos de grande escala. Neste trabalho nós caracterizamos a transmissão ao vivo pela Internet de dois eventos esportivos de grande escala. Esses eventos foram transmitidos gratuitamente por um dos maiores provedores de conteúdo da América Latina através de um portal web acessado pelo protocolo HTTP. Nos baseamos em registros de acesso dos servidores web do provedor para extrair as informações usadas nas caracterizações. Nós quantificamos o impacto da transmissão de um evento de grande escala no provedor de conteúdo e a qualidade de serviço recebida pelos usuários finais. Mostramos que os servidores de vídeo recebem carga substancial e que a carga varia significativamente entre jogos, o que dificulta o provisionamento de capacidade. Além disso apresentamos um mapa da difusão de acesso por região do Brasil com base em observações sobre a mídia recebida pelos clientes. / Streaming media on internet is currently a growing trend. In particular, video-on-demand (VoD) scenario is already quite consolidated. Although, live streaming still facing challenges, specially during large-scale events, which may attract a large number of viewers. In this work, we characterize two large-scale Internet live streaming sport events. These events were streamed free of charge through a web portal accessed via HTTP protocol by one of the largest content provider in Latin America. Our characterization relies on access logs we have obtained from the content provider’s web server. We quantify the impact of a large-scale event transmission on content provider servers. We also characterize the quality of service end users receive. Our results show that video servers receive substantial network load during a large-scale event. Moreover, this network load can vary significantly among distinct matches, which difficult capacity provisioning. In addition we present a map of the Brazilian Internet access distribution based on observations about the media content received by customers.

Submitted by Renata Lopes (renatasil82@gmail.com) on 2017-06-06T14:59:44Z No. of bitstreams: 1 biancaportesdecastro.pdf: 1203353 bytes, checksum: 0cd5843bff9e747e5432fff99ec1e565 (MD5) / Approved for entry into archive by Adriana Oliveira (adriana.oliveira@ufjf.edu.br) on 2017-06-07T11:04:29Z (GMT) No. of bitstreams: 1 biancaportesdecastro.pdf: 1203353 bytes, checksum: 0cd5843bff9e747e5432fff99ec1e565 (MD5) / Made available in DSpace on 2017-06-07T11:04:29Z (GMT). No. of bitstreams: 1 biancaportesdecastro.pdf: 1203353 bytes, checksum: 0cd5843bff9e747e5432fff99ec1e565 (MD5) Previous issue date: 2014-08-25 / CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Aplicações multimídia são muito populares na internet. Grande parte delas necessita de multicast para escalar. É sabido que multicast em nível de redes não foi implementado como desejado. Protocolos em nível de aplicação são a solução atual. Apesar do sucesso dos protocolos ALM (Application Layer Multicast), a maioria dos protocolos existentes são custosos e acarretam grande sobrecarga de controle à rede. Neste trabalho, apresentamos um novo protocolo de fluxo contínuo baseado em árvore, utilizando a desigualdade triangular entre cada três peers para gerenciamento dinâmico da topologia (o PALMS+). O novo protocolo é simples e com baixa sobrecarga. Mesmo assim, seu desempenho é tão bom quanto o estado da arte. Experimentos realizados na plataforma Oversim (OMNet++) demonstraram que o PALMS+ manteve desempenho tão bom quanto o estado da arte (e.g. protocolo NICE), mesmo quando submetido a alto churn em uma rede heterogênea. De fato, a sobrecarga nos peers do novo protocolo é menor que 10% da sobrecarga gerada pelo NICE. O protocolo PALMS+ entrega os dados em menos de 1,5s. O novo protocolo mostra-se adequado a vídeo ao vivo, escalando mesmo em cenários realistas e com alto churn. / Multimedia applications are very popular on the internet. Many of these applications need multicast to scale. However, network layer multicast has not been implemented in the internet. Application layer multicast (ALM) protocols are a practical alternative. However, despite their popularity, many existing ALM protocols and mechanisms are expensive and bring a large overhead control on the network. In the present work, a new protocol is proposed for content distribution based on tree, using the triangular inequality between every three peers to dynamic topology control (the PALMS+). The new protocol is simple and with low overhead. Nevertheless, its performance as good as the state of the art. Experimental results conducted with the OverSim platform (OMNet++) suggest that PALMS+ improves the performance of a state-of-art implementation of ALM protocol when compared against the NICE protocol. Furthermore, the control message overhead at peers using the PALMS+ protocol is reduced by 10%, when compared with NICE. In the PALMS+ protocol, chunks are delivered up to 1,5s. Results confirm that proposed implementation of PALMS+ is very suitable to real-time video streaming, even when churn is high.