abstract: Broadcast Encryption is the task of cryptographically securing communication in a broadcast environment so that only a dynamically specified subset of subscribers, called the privileged subset, may decrypt the communication. In practical applications, it is desirable for a Broadcast Encryption Scheme (BES) to demonstrate resilience against attacks by colluding, unprivileged subscribers. Minimal Perfect Hash Families (PHFs) have been shown to provide a basis for the construction of memory-efficient t-resilient Key Pre-distribution Schemes (KPSs) from multiple instances of 1-resilient KPSs. Using this technique, the task of constructing a large t-resilient BES is reduced to finding a near-minimal PHF of appropriate parameters. While combinatorial and probabilistic constructions exist for minimal PHFs with certain parameters, the complexity of constructing them in general is currently unknown. This thesis introduces a new type of hash family, called a Scattering Hash Family (ScHF), which is designed to allow for the scalable and ingredient-independent design of memory-efficient BESs for large parameters, specifically resilience and total number of subscribers. A general BES construction using ScHFs is shown, which constructs t-resilient KPSs from other KPSs of any resilience ≤w≤t. In addition to demonstrating how ScHFs can be used to produce BESs , this thesis explores several ScHF construction techniques. The initial technique demonstrates a probabilistic, non-constructive proof of existence for ScHFs . This construction is then derandomized into a direct, polynomial time construction of near-minimal ScHFs using the method of conditional expectations. As an alternative approach to direct construction, representing ScHFs as a k-restriction problem allows for the indirect construction of ScHFs via randomized post-optimization. Using the methods defined, ScHFs are constructed and the parameters' effects on solution size are analyzed. For large strengths, constructive techniques lose significant performance, and as such, asymptotic analysis is performed using the non-constructive existential results. This work concludes with an analysis of the benefits and disadvantages of BESs based on the constructed ScHFs. Due to the novel nature of ScHFs, the results of this analysis are used as the foundation for an empirical comparison between ScHF-based and PHF-based BESs . The primary bases of comparison are construction efficiency, key material requirements, and message transmission overhead. / Dissertation/Thesis / M.S. Computer Science 2012

The "tabloid TV" genre, like tabloid newspapers has been chastised for depoliticising the public by causing cynicism, and lowering the standards of rational public discourse. Such criticisms are not always based on a close interrogation of the reasons for the popularity of such a genre amongst its consumers. The "tabloid TV" news genre is a relatively new phenomenon in Zambia and in the African context in general. This study is an investigation of the rise in popularity of the Zambian television station, Muvi TV. It is a reception study of Lusaka (capital city) viewers, particularly the working class community, who make up the majority of the TV stations' audience. Members of this social group who have hitherto been marginalised from mainstream media discourses were interviewed. In particular, the study explores the meanings obtained from the content of Muvi TVs' tabloidised main evening news and its relevance to their everyday lived experiences. The TV station gives prominence to "micro-politics of everyday life", alongside "serious" stories albeit in a more lurid, sensationalised and personalised manner. In undertaking this investigation, the study draws primarily on qualitative in-depth interviews - focus group and individual. These techniques unearth the manner in which the viewers decode the messages and appropriate the meanings into their lived experiences. The study establishes that the popularity of Muvi TV is due to the emphasis on human-interest stories epitomised by tabloid journalism values. The working class majority is able to relate and identify with these stories, and attaches greater believability to the station's news as compared to the public broadcaster, the Zambia National Broadcasting Corporation (ZNBC). As such, Muvi TV can be seen to fulfil a political function despite its sensationalised approach.

Submitted by Diogo Barreiros (diogo.barreiros@ufba.br) on 2017-02-06T16:51:35Z No. of bitstreams: 1 Dissertacao de Mestrado - Bruno Rios Patriarca Nunes.pdf: 1161824 bytes, checksum: ad90a85de8a47398b1ead19074bc473d (MD5) / Approved for entry into archive by Vanessa Reis (vanessa.jamile@ufba.br) on 2017-02-07T11:42:36Z (GMT) No. of bitstreams: 1 Dissertacao de Mestrado - Bruno Rios Patriarca Nunes.pdf: 1161824 bytes, checksum: ad90a85de8a47398b1ead19074bc473d (MD5) / Made available in DSpace on 2017-02-07T11:42:36Z (GMT). No. of bitstreams: 1 Dissertacao de Mestrado - Bruno Rios Patriarca Nunes.pdf: 1161824 bytes, checksum: ad90a85de8a47398b1ead19074bc473d (MD5) / Redes de sensores sem o (RSSF) são compostas por um conjunto de dispositivos, geralmente de baixa capacidade de processamento e autonomia de energia limitada, com o objeto de coletar dados sobre a area onde foi instalada e envia-los ate as unidades de processamento chamadas de estações base. Dentre os recursos de um no sensor, pode-se considerar como um dos mais críticos a carga de bateria, ja que ela de ne em ultimo caso o tempo de vida util do no. Por conta disso, e necessario que os protocolos e aplicações otimizem o uso de energia a m de prolongar o tempo de vida do no sensor e, consequentemente, de toda a RSSF.Este trabalho dedica-se a estudar o problema da maximiza¸c˜ao do tempo de vida da rede durante uma s´erie de opera¸c˜oes de broadcast. Para o escopo desta pesquisa, o tempo de vida da rede de sensor ´e definido como o tempo at´e a falha do primeiro n´o por falta de energia. H´a diversos protocolos na literatura que buscam minimizar o consumo de energia durante a dissemina¸c˜ao de mensagens na rede, por´em neles n˜ao s˜ao considerados aspectos como o custo de recep¸c˜ao ou a presen¸ca de links assim´etricos entre os n´os. Neste trabalho, propomos o algoritmo DLMCA para o problema de maximiza¸c˜ao do tempo de vida da rede. O algoritmo DLMCA baseia-se na constru¸c˜ao de arborescˆencias de custo m´ınimo, ´e localizado e considera redes com custos de comunica¸c˜ao assim´etricos, o que ´e especialmente importante em casos em que a RSSF ´e composta por dispositivos diferentes. Os experimentos realizados mostraram que o DLMCA ´e mais eficiente que solu¸c˜oes alternativas propostas na literatura. A heur´ısitca oferecida pelo DLMCA para redes est´aticas foi levemente adaptada e o problema tamb´em foi analisado para redes m´oveis. Para estas redes, os experimentos demonstraram que a solu¸c˜ao baseada no DLMCA tamb´em foi superior em rela¸c˜ao a outras propostas tanto em rela¸c˜ao `a energia total gasta em cada operação de broadcast quanto em relação ao tempo de vida da rede.

As trajetórias e as atuações profissionais de duas personalidades emblemáticas do campo artístico-intelectual das Américas no século XX – Alan Lomax e Radamés Gnattali – apresentam-se nesta investigação como elementos centrais para a aproximação entre os projetos político-culturais implementados no âmbito das relações Brasil-EUA no período entre 1939 e 1945. O agenciamento desses atores foi determinante na criação de modelos de performatização musical utilizados em programas radiofônicos de conteúdo "folclórico", que, segundo se infere, contribuíram para as transformações políticas e culturais por que passaram ambos os países durante a 2ª Guerra Mundial. Do ponto de vista teórico-metodológico, a hipótese que justifica uma aproximação entre os projetos é que tanto as técnicas de arranjo utilizadas por Gnattali para os programas feitos em parceria com Almirante na Rádio Nacional do Brasil (1941-1945) como as performances musicais conduzidas por Lomax e seus convidados nos programas da CBS nos EUA (1939-1941) podem ser interpretadas como processos de agenciamento entre os produtores, os grupos sociais representados nos programas, os modelos ideológicos defendidos por intelectuais especializados no estudo do folclore e os interesses políticos dos regimes. Esses núcleos de poder, portanto, se relacionariam de forma heterogênea em relação à identidade nacional nos diferentes contextos em que foram inseridos. Por meio de exemplos de programas da série Wellspring of music – escrita e produzida por Alan Lomax para o projeto American School of the Air – e da série Aquarelas do Brasil – produzida por Radamés Gnattali, Almirante e José Mauro e patrocinada pela empresa norte-americana Pan-American World Airlines –, busca-se examinar as estratégias utilizadas para a criação dos modelos de performance musical responsáveis pelos processos de comunicação simbólica operados pelos programas, que teriam contribuído tanto no Brasil como nos EUA para a construção de identidades nacionais utilizadas nos contextos regionais e pan-americanos. / The study of the trajectories and professional activities of two emblematic personalities on the artistic and intellectual scene of the Americas in the 20th century – Alan Lomax and Radames Gnattali – present themselves in this investigation as central elements in the analysis between the cultural projects and policies implemented under Brazil-US relations in the period between 1939-1945. To this end, this research seeks to examine, through a theoretical and methodological perspective, how the these actors’ agency were instrumental in creating different performance models related with "folk" content used in radio shows that intended to contribute to the political and cultural transformations faced by both countries during the Second World War. The hypothesis for this relationship between the trajectories is that both Gnattali’s arrangement techniques used in the programs in partnership with Almirante at the National Radio of Brazil (1941-1945), and the idealized musical performances used by Lomax and his partners for the series produced by CBS in the USA (1939-1941), could be perceived as mediation processes between the social groups represented on the radio shows, the ideological models advocated by intellectuals linked to folklore, and the political interests that took part in national and international schemes. These centers of power, therefore, would deal heterogeneously in relation to their identities in the contexts in which they were performed. Using examples of two programs – one from the series "Wellspring of Music," written and produced by Lomax that was part of the project American School of the Air, and one from the program "Aquarelas do Brasil" [Watercolors of Brazil] produced by Radamés Gnattali and Almirante and sponsored by Pan American World Airlines—the research will also highlight the strategies used in the musical performances developed by those radio producers as a mediation field in relation to the semiotic process, as sound material became important symbols of national identity used in national and Pan-American projects.

Made available in DSpace on 2016-08-03T12:31:21Z (GMT). No. of bitstreams: 1 Walter Alberto de Luca Texto-PDF.pdf: 1294802 bytes, checksum: 4d5b2f03e1c9670ad7275ffd85b944f3 (MD5) Previous issue date: 2011-03-17 / This thesis reflects about the decline of the audience of the big broadcast television networks and how producers deal with this global trend. It brings an overview about the matter in the world and focuses particularly the case of Brazil, where the three main television channels have had historically some of the highest rates of audience compared to the major networks of other countries. After analyzing the fragmentation of televiewing audiences in the last two decades and the numbers that show the increasing dispersion of the public attention among the multiples choices of media available nowadays, the study discuss the strategies of programming and content construction based on writers and producers opinions and on the exam of important TV programs. The purpose is to expose the efforts required to attract, sustain and retain televiewers attention. These efforts start with audience measurements and researches about consumers attitudes and interests toward TV, which defines the agenda of themes and the techniques to write, direct and edit programs. The research discusses also how exposure of televiewers occurs in an environment where consumers have multiple choices of screens to choose television programs and other media activities. It considers that exposure is an essential condition to support the study of other approaches of the communication process, such as the influence of the media over culture and society. In a context where media occupies so much time of our personal life, the impact of the mass media might be proportionally direct to the number of people they reach, to the habits of consuming information and entertainment and to the time dedicated to accessing them. / Esta tese aborda o declínio da audiência das grandes redes de TV aberta e os recursos narrativos que os produtores de programas adotaram para enfrentar essa tendência mundial. O estudo traz um panorama da situação da audiência no âmbito internacional e foca, particularmente, o caso do Brasil, onde três grandes emissoras mantém, no conjunto, uma das mais altas concentrações de público do mundo. Depois de analisar a fragmentação das audiências televisivas nas duas últimas décadas e os números que indicam a crescente dispersão dos telespectadores entre múltiplas ofertas de mídia disponíveis nos dias atuais, o trabalho discute as estratégias de programação e de construção de conteúdos. Além de teóricos que pesquisaram a chamada semiótica televisiva , servem de base para a investigação depoimentos de produtores e análises de programas de grande audiência. O objetivo é revelar os procedimentos utilizados para atrair e manter a atenção dos telespectadores, os quais começam com as medições de audiência e os estudos sobre o comportamento dos consumidores em relação à TV. A tese discute também como ocorre a exposição dos telespectadores em um ambiente onde existem várias opções de dispositivos para ver atrações televisivas ou para fazer outras atividades comunicacionais. A escolha deste tema de investigação partiu do princípio de que a exposiçao é condição essencial para sustentar o estudo de outras fases e outros aspectos do processo de comunicação, como a influência dos meios sobre a cultura e a sociedade. Em um contexto onde a mídia ocupa tanto tempo de nosso cotidiano, o impacto dos meios de comunicação de massa pode ser diretamente proporcional ao número de pessoas que eles alcançam e aos nossos hábitos de consumo de informação e entretenimento.

Made available in DSpace on 2016-08-03T12:31:22Z (GMT). No. of bitstreams: 1 Walter Alberto de Luca capa.pdf: 186781 bytes, checksum: 53d1500312d4e074ce5c3764968f25e3 (MD5) Previous issue date: 2011-03-17 / This thesis reflects about the decline of the audience of the big broadcast television networks and how producers deal with this global trend. It brings an overview about the matter in the world and focuses particularly the case of Brazil, where the three main television channels have had historically some of the highest rates of audience compared to the major networks of other countries. After analyzing the fragmentation of televiewing audiences in the last two decades and the numbers that show the increasing dispersion of the public attention among the multiples choices of media available nowadays, the study discuss the strategies of programming and content construction based on writers and producers opinions and on the exam of important TV programs. The purpose is to expose the efforts required to attract, sustain and retain televiewers attention. These efforts start with audience measurements and researches about consumers attitudes and interests toward TV, which defines the agenda of themes and the techniques to write, direct and edit programs. The research discusses also how exposure of televiewers occurs in an environment where consumers have multiple choices of screens to choose television programs and other media activities. It considers that exposure is an essential condition to support the study of other approaches of the communication process, such as the influence of the media over culture and society. In a context where media occupies so much time of our personal life, the impact of the mass media might be proportionally direct to the number of people they reach, to the habits of consuming information and entertainment and to the time dedicated to accessing them. / Esta tese aborda o declínio da audiência das grandes redes de TV aberta e os recursos narrativos que os produtores de programas adotaram para enfrentar essa tendência mundial. O estudo traz um panorama da situação da audiência no âmbito internacional e foca, particularmente, o caso do Brasil, onde três grandes emissoras mantém, no conjunto, uma das mais altas concentrações de público do mundo. Depois de analisar a fragmentação das audiências televisivas nas duas últimas décadas e os números que indicam a crescente dispersão dos telespectadores entre múltiplas ofertas de mídia disponíveis nos dias atuais, o trabalho discute as estratégias de programação e de construção de conteúdos. Além de teóricos que pesquisaram a chamada semiótica televisiva , servem de base para a investigação depoimentos de produtores e análises de programas de grande audiência. O objetivo é revelar os procedimentos utilizados para atrair e manter a atenção dos telespectadores, os quais começam com as medições de audiência e os estudos sobre o comportamento dos consumidores em relação à TV. A tese discute também como ocorre a exposição dos telespectadores em um ambiente onde existem várias opções de dispositivos para ver atrações televisivas ou para fazer outras atividades comunicacionais. A escolha deste tema de investigação partiu do princípio de que a exposiçao é condição essencial para sustentar o estudo de outras fases e outros aspectos do processo de comunicação, como a influência dos meios sobre a cultura e a sociedade. Em um contexto onde a mídia ocupa tanto tempo de nosso cotidiano, o impacto dos meios de comunicação de massa pode ser diretamente proporcional ao número de pessoas que eles alcançam e aos nossos hábitos de consumo de informação e entretenimento.

O objetivo desta dissertação é pensar a transmissão direta via televisão a partir do que aqui se denomina tempo morto, períodos menos concentrados de fluxo do evento transmitido. Em toda teletransmissão, há embates entre dois fluxos informativos distintos – o do evento e o da televisão –, que são resolvidos segundo processos (moldurações) que expressam figuras (molduras) propriamente televisivas. Ao circunscrever a observação aos tempos mortos, pode-se compreender com maior clareza que estratégias televisivas são empregadas nesta transposição. O objeto de estudo é o futebol televisivo, a partir da observação das onze últimas finais de Copas do Mundo (1970-2010). Nelas, são identificadas algumas figuras de tempo morto, como imagens de personas e figuras de manipulação temporal, analisadas sincrônica e diacronicamente. / The aim of this work is to think direct broadcast television from what is called dead time herein, periods less concentrated of flow of the event broadcast. Throughout teletransmission there is clashes between two different information flows - the event and the television - which are resolved in accordance with processes (moldurações) expressing television figures (molduras). When observing the dead time, one can understand more clearly what strategies are employed in this transposition of an event to the television. The object of study is football, based on the observation of the eleven last World Cups final games (1970-2010).

This study examines the representation of Local Education Authority (LEA) secondary schooling in England and Wales as it was portrayed in non-fiction British Broadcasting Corporation (BBC) programmes in the twenty-one years that followed the 1944 Education Act. The primary sources drawn on for this study include the surviving microfilmed radio scripts, dating from 1944–1965 and held at the BBC Written Archives (BBC WAC). The correspondence files from contributors to programmes also provide a key source from BBC WAC. The majority of the programmes considered are radio broadcast, however some documentary films on the topic of secondary education, made by the BBC and transmitted on television, are also analysed. Where audio-visual copies have survived, the programmes were viewed at the BFI Viewing Services. The study draws on 235 BBC programmes in total, made in the years 1944–1965. The details of these broadcasts can be seen in the three Appendices accompanying this study. The study also employs the use of drawing to present key ideas. This study explores how broadcasts are formed as cultural products. The research questions address: what was the content of these programmes? Who collaborated to create and edit these programmes and how were the programmes devised to inform the public about the provision of secondary education? What was the role of the All Souls Group (ASG) in this collaboration? The public included a domestic audience in England and Wales and an overseas audience for whom distinct broadcasts were usually created. A further element of the research is a scrutiny of the BBC as an organization that positions itself as neutral. The considered programmes enabled a group of eloquent educationalists to use their rehearsed and edited ‘conversation’ on a public stage. As the study unfolds it becomes apparent that the members of the informal education discussion group, the ASG, were lobbying to encourage the topic of secondary education to resurface sufficiently often on air. The study concludes with recognition that the reinforcing of loyalties between overlapping networks, such as the BBC and the ASG, should no longer be approached with reticence in academic research.

Master of Science / Department of Journalism and Mass Communications / Barbara DeSanto / The purpose of this study was to take a closer look at the use of advanced statistics in Major League Baseball (MLB) radio broadcasts and the possible effects usage could have on the roles of MLB broadcasters. This study used a theoretical framework supported by role theory and diffusion of innovations theory. The study employed in-depth interviews of eight MLB radio broadcasters to get a better understanding of the broadcasters’ thoughts on the value of advanced statistics, how using advanced statistics could affect their role as a broadcaster, the factors that influence the potential inclusion of advanced statistics in their broadcasts, and ultimately, whether broadcasters perceived advanced statistics as a trend or a fad. The interviews revealed a number of things about the baseball broadcasting industry with disagreements appearing in regards to techniques in using advanced statistics in broadcasts and the value of advanced statistics to listeners. Despite the disagreements, the most important finding was the unanimous belief that advanced statistics are not a fad, but rather something that will remain a part of baseball broadcasts going forward.

abstract: ABSTRACT Modern management techniques to maintain rangelands and deter encroachment of juniper into grassland habitats currently includes fire prescription. Additionally, a large body of research has indicated that fire has multiple benefits to grasslands resulting in increased diversity of flora and fauna. In the semi-arid grassland of the Agua Fria National Monument, fire treatments may be able to provide similar advantages. This study considers two methods of fire prescription on the Agua Fria National Monument within central Arizona: 1) Juniper thinning with pile burning; 2) Broadcast burning. The Agua Fria National Monument upland ecosystem has limited research focusing on semi-arid grassland and juniper stand’s response to implemented treatments over time. The four year monitoring duration of this study aids in assessing the outcome of treatments and reaching the objectives of the management plan. Vegetation in 981 quadrats was measured for species richness, cover, densities, height, and biomass during the fire prescription period from 2009 through 2013. The study was divided into two treatment types: 1) Juniper cutting and pile burn; 2) Broadcast burn areas in open grasslands. Results of this study provide consistent examples of vegetative change and community movement towards positive response. Percent composition of overall vegetation is 5 – 30% with >50% of litter, bare ground and rock cover. Juniper sites have immediate consequences from tree thinning activities that may be beneficial to wildlife, particularly as connective corridors pronghorn antelope. Grass height was significantly reduced as well as forb density. Forbs that are highly responsive to environmental factors indicate an increase after the second year. Analysis results from grasslands indicated that cactus and unpalatable shrubs are reduced by fire but a return to pre-burn conditions occur by the third year after fire disturbance. Percent cover of perennial grasses has shown a slow increase. Wright’s buckwheat, a palatable shrub, has increased in density and height, indicating fire adaptations in the species. Species richness was reduced in the first year but increase in density continues into the third year after burn. / Dissertation/Thesis / Masters Thesis Applied Biological Sciences 2015