Entrega de conteúdos multimédia em over-the-top: caso de estudo das gravações automáticas

Doutoramento em Engenharia EletrotécnicaOver-The-Top (OTT) multimedia delivery is a very appealing approach for providing ubiquitous, exible, and globally accessible services capable of low-cost and unrestrained device targeting. In spite of its appeal, the underlying delivery architecture must be carefully planned and optimized to maintain a high Qualityof- Experience (QoE) and rational resource usage, especially when migrating from services running on managed networks with established quality guarantees. To address the lack of holistic research works on OTT multimedia delivery systems, this Thesis focuses on an end-to-end optimization challenge, considering a migration use-case of a popular Catch-up TV service from managed IP Television (IPTV) networks to OTT. A global study is conducted on the importance of Catch-up TV and its impact in today's society, demonstrating the growing popularity of this time-shift service, its relevance in the multimedia landscape, and tness as an OTT migration use-case. Catch-up TV consumption logs are obtained from a Pay-TV operator's live production IPTV service containing over 1 million subscribers to characterize demand and extract insights from service utilization at a scale and scope not yet addressed in the literature. This characterization is used to build demand forecasting models relying on machine learning techniques to enable static and dynamic optimization of OTT multimedia delivery solutions, which are able to produce accurate bandwidth and storage requirements' forecasts, and may be used to achieve considerable power and cost savings whilst maintaining a high QoE. A novel caching algorithm, Most Popularly Used (MPU), is proposed, implemented, and shown to outperform established caching algorithms in both simulation and experimental scenarios. The need for accurate QoE measurements in OTT scenarios supporting HTTP Adaptive Streaming (HAS) motivates the creation of a new QoE model capable of taking into account the impact of key HAS aspects. By addressing the complete content delivery pipeline in the envisioned content-aware OTT Content Delivery Network (CDN), this Thesis demonstrates that signi cant improvements are possible in next-generation multimedia delivery solutions.A entrega de conteúdos multimédia em Over-The-Top (OTT) e uma proposta atractiva para fornecer um serviço flexível e globalmente acessível, capaz de alcançar qualquer dispositivo, com uma promessa de baixos custos. Apesar das suas vantagens, e necessario um planeamento arquitectural detalhado e optimizado para manter níveis elevados de Qualidade de Experiência (QoE), em particular aquando da migração dos serviços suportados em redes geridas com garantias de qualidade pré-estabelecidas. Para colmatar a falta de trabalhos de investigação na área de sistemas de entrega de conteúdos multimédia em OTT, esta Tese foca-se na optimização destas soluções como um todo, partindo do caso de uso de migração de um serviço popular de Gravações Automáticas suportado em redes de Televisão sobre IP (IPTV) geridas, para um cenário de entrega em OTT. Um estudo global para aferir a importância das Gravações Automáticas revela a sua relevância no panorama de serviços multimédia e a sua adequação enquanto caso de uso de migração para cenários OTT. São obtidos registos de consumos de um serviço de produção de Gravações Automáticas, representando mais de 1 milhão de assinantes, para caracterizar e extrair informação de consumos numa escala e âmbito não contemplados ate a data na literatura. Esta caracterização e utilizada para construir modelos de previsão de carga, tirando partido de sistemas de machine learning, que permitem optimizações estáticas e dinâmicas dos sistemas de entrega de conteúdos em OTT através de previsões das necessidades de largura de banda e armazenamento, potenciando ganhos significativos em consumo energético e custos. Um novo mecanismo de caching, Most Popularly Used (MPU), demonstra um desempenho superior as soluções de referencia, quer em cenários de simulação quer experimentais. A necessidade de medição exacta da QoE em streaming adaptativo HTTP motiva a criaçao de um modelo capaz de endereçar aspectos específicos destas tecnologias adaptativas. Ao endereçar a cadeia completa de entrega através de uma arquitectura consciente dos seus conteúdos, esta Tese demonstra que são possíveis melhorias de desempenho muito significativas nas redes de entregas de conteúdos em OTT de próxima geração

Information systems failure: A business-led knowledge requirements framework for modelling business requirements

This thesis was submitted for the degree of Doctor of Philosophy and awarded by Brunel University.Our work will be mainly concerned with improving the crucial first stage (the requirements stage) of any system development methodology in order to improve requirements. A framework has been developed, called "knowledge requirements framework (KRF)" to help customers and system developers bridge the knowledge and understanding gaps at the initial requirements stage of the Information Technology System (ITS) development process. Unclear business requirements, mismatch of knowledge and understanding are among the major factors that contributes to some ITS failures worldwide. The aim is to capture functional requirements at the initial stage of the system development process and to integrate systems and people use them in the development process. Multi-surveys are conducted, capture and highlight the criteria of initial requirements exactness and executability. Knowledge and understanding gaps, which occur in the development process, are described. These gaps constitute the problem at the invisible architecture in the initial requirements stage, as they expose mismatch of both knowledge and understanding problems (Requirements/Specifications). A notation to describe this framework is elaborated, novel techniques and tools for the construction and application of customer requirements in systems development are developed and used in KRF to facilitate bridging these gaps. The resulting prototype KRF is developed and used against some example problems in retail organisations, and so shown to be sufficient in principle of handling all the negotiation problems at the initial requirements stage, singly and in combination. Also, it is shown how KRF sub-process can be combined and used to elicit information and knowledge mining between both the customer and the system developer using human communication and interaction capture as an example. Systems these days are living systems, changeable, in business and the human factor in developing them cannot be excluded. It is further shown how these techniques and tools can be augmented with established methodologies rather than inventing new ones and to enable management to react as quickly as possible to global changing market conditions. This proposed framework is also evaluated and tested against the original criteria of initial requirements, exactness and executability

Information systems failure : a business-led knowledge requirements framework for modelling business requirements

Our work will be mainly concerned with improving the crucial first stage (the requirements stage) of any system development methodology in order to improve requirements. A framework has been developed, called "knowledge requirements framework (KRF)" to help customers and system developers bridge the knowledge and understanding gaps at the initial requirements stage of the Information Technology System (ITS) development process. Unclear business requirements, mismatch of knowledge and understanding are among the major factors that contributes to some ITS failures worldwide. The aim is to capture functional requirements at the initial stage of the system development process and to integrate systems and people use them in the development process. Multi-surveys are conducted, capture and highlight the criteria of initial requirements exactness and executability. Knowledge and understanding gaps, which occur in the development process, are described. These gaps constitute the problem at the invisible architecture in the initial requirements stage, as they expose mismatch of both knowledge and understanding problems (Requirements/Specifications). A notation to describe this framework is elaborated, novel techniques and tools for the construction and application of customer requirements in systems development are developed and used in KRF to facilitate bridging these gaps. The resulting prototype KRF is developed and used against some example problems in retail organisations, and so shown to be sufficient in principle of handling all the negotiation problems at the initial requirements stage, singly and in combination. Also, it is shown how KRF sub-process can be combined and used to elicit information and knowledge mining between both the customer and the system developer using human communication and interaction capture as an example. Systems these days are living systems, changeable, in business and the human factor in developing them cannot be excluded. It is further shown how these techniques and tools can be augmented with established methodologies rather than inventing new ones and to enable management to react as quickly as possible to global changing market conditions. This proposed framework is also evaluated and tested against the original criteria of initial requirements, exactness and executability.EThOS - Electronic Theses Online ServiceGBUnited Kingdo

Annual Report of the University, 2001-2002, Volumes 1-4

VITAL ACADEMIC CLIMATE* by Brian Foster, Provost/Vice President of Academic Affairs A great university engages students and faculty fully in important ideas and issues ... not just to learn about them, but to take them apart and put them back together, to debate, deconstruct, resist, reconstruct and build upon them. Engagement of this sort takes concentration and commitment, and it produces the kind of discipline and passion that leads to student and faculty success and satisfaction in their studies, research, performance, artistic activity and service. It is also the kind of activity that creates a solid, nurturing spirit of community. This is what we mean when we talk about a vital academic climate. We are striving for an environment that will enrich the social, cultural and intellectual lives of all who come in contact with the University. Many things interconnect to make this happen: curriculum, co-curricular activities, conferences, symposia, cultural events, community service, research and social activity. Our goal is to create the highest possible level of academic commitment and excitement at UNM. This is what characterizes a truly great university. *Strategic Direction 2 New Mexico native Andres C. Salazar, a Ph.D. in electrical engineering from Michigan State University, has been named the PNM Chair in Microsystems, Commercialization and Technology. Carrying the title of professor, the PNM Chair is a joint appointment between the School of Engineering and the Anderson Schools of Management. Spring 2002 graduate John Probasco was selected a 2002 Rhodes Scholar, the second UNM student to be so honored in the past four years. The biochemistry major from Alamogordo previously had been awarded the Goldwater Scholarship and the Truman Scholarship. Andres c. Salazar Biology student Sophie Peterson of Albuquerque was one of 30 students nationwide to receive a 2002-2003 Award of Excellence from Phi Kappa Phi, the oldest and largest national honor society. Regents\\u27 Professor of Communication and Journalism Everett M. Rogers was selected the University\\u27s 4 71h Annual Research Lecturer, the highest honor UNM bestows upon members of its faculty. John Probasco honored by Student Activities Director Debbie Morris. New Mexico resident, author and poet Simon}. Ortiz received an Honorary Doctorate of Letters at Spring Commencement ceremonies. Child advocate Angela Angie Vachio, founder and executive director of Peanut Butter and Jelly Family Services, Inc., was awarded an Honorary Doctorate of Humane Letters. American Studies Assistant Professor Amanda}. Cobb won the 22 d annual American Book Award for listening to Our Grandmothers\\u27 Stories: The Bloomfield Academy for Chickasaw Females, 1852-1949

Federal Register

Daily publication of the U.S. Office of the Federal Register contains rules and regulations, proposed legislation and rule changes, and other notices, including "Presidential proclamations and Executive Orders, Federal agency documents having general applicability and legal effect, documents required to be published by act of Congress, and other Federal agency documents of public interest" (p. ii). Table of Contents starts on page iii

Central Washington University 2018-2019 Undergraduate Catalog

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The HBP1 tumor suppressor is a negative epigenetic regulator of MYCN driven neuroblastoma through interaction with the PRC2 complex

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