Network programming is one of the most important applications in Wireless Sensor Networks as It provides an efficient way to update program Images running on sensor nodes without physical access to them. Securing these updates, however, remains a challenging and important issue, given the open deployment environment of sensor nodes. Though several security schemes have been proposed to impose the authenticity and Integrity protection on network programming applications, they are either energy Inefficient as they tend to use digital signature or lacks the data confidentiality. In addition, due to the absence of secure memory management in the current sensor hardware, the attacker could inject malicious code into the program flash by exploiting buffer overflow In the memory despite the secure code dissemination. The contribution of this thesis Is to provide two software-based security protocols and one hardware-based remote attestation protocol for network programming application. Our first protocol deploys multiple one-way key chains for a multi-hop sensor network. The scheme Is shown to be lower In computational, power consumption and communication costs yet still able to secure multi??hop propagation of program images. Our second protocol utilizes an Iterative hash structure to the data packets in network programming application, ensuring the data confidentiality and authenticity. In addition, we Integrated confidentiality and DoS-attack-resistance in a multi??hop code dissemination protocol. Our final solution is a hardware-based remote attestation protocol for verification of running codes on sensor nodes. An additional piece of tamper-proof hardware, Trusted Platform Module (TPM), is imposed into the sensor nodes. It secures the sensitive information (e.g., the session key) from attackers and monitors any platform environment changes with the Internal registers. With these features of TPM, the code Injection attack could be detected and removed when the contaminated nodes are challenged in our remote attestation protocol. We implement the first two software-based protocols with Deluge as the reference network programming protocol in TinyOS, evaluate them with the extensive simulation using TOSSIM and validate the simulation results with experiments using Tmote. We implement the remote attestation protocol on Fleck, a sensor platform developed by CSIRO that Integrates an Atmel TPM chip.

Thesis (M.Sc. (Computer Science)) - Rhodes University, 2008.

Research shows that black people watch more television than any other race of people, and, given that television is the most influential media tool, the content of what may affect an audience’s behavior and beliefs deserves analysis. This study examines the black family, alleged pathology, strengths that are specifically associated with them, its portrayal on television, and how television is used as a tool for socialization and influence. A content analysis of the top thirty black family shows that appeared on major network television between 1980 and 2000 was conducted to determine if the family framed was portrayed realistically. Each show analyzed was found to portray some characteristic of strong black families, attributes some media and social critics had not previously recognized or acknowledged. This study suggests that further research is warranted from black family, cultural, and media scholars, as well as social policy and program makers, and on how television influences entire cultures to shift socially and economically.

This study is a policy investigation of community radio broadcasting in Zambia. The emergence of this tier of broadcasting can be traced to the 1990s, following the country's policy of politico-economic liberalisation. The state broadcasting system had hitherto reigned supreme. Based upon a focused synthesis of a range of historical, political, policy, regulatory and other factors, within the context of participatory development communication, this study proposes a normative policy model for community radio broadcasting in Zambia. To begin with, the study focuses on the historical factors that have influenced the development of community radio broadcasting in the country, particularly in the period before and after 1991. This historical analysis establishes the fact that the shape that community radio broadcasting has assumed in Zambia is largely reflective of the state-centric policy-making regime. This policy-making regime is itself a legacy of British colonialism. Next, the study offers a conceptual framework of community radio broadcasting. It analyses several theoretical antecedents upon which the conceptual edifice of community radio broadcasting would seem to be built. In particular, the study explores the contributions of media effects and normative media theories towards the conceptual underpinnings of community radio broadcasting. Furthermore, as an attempt at establishing some empirical referents for developing a community radio broadcasting policy for Zambia, the study delves into a comparative analysis of trends in broadcast policy and regulatory practices throughout the world, with a special focus on Malawi, Mozambique, South Africa and Australia. This comparative policy analysis reveals differentiated levels of sophistication of policy-cum-regulatory models relating to community radio broadcasting. This provides a wealth of chequered experiences for Zambia to learn from. To further substantiate the case for a policy model, the study examines selected community radio initiatives in Zambia. Finally, based upon this focused synthesis, the study proposes a normative policy model for community radio broadcasting in Zambia. The policy proposal, informed by the assumptions of the group and organised anarchy models of policy-making, seeks to promote community radio broadcasting in terms of its vision, regulatory structures, funding, training, facilities, technology, production of local content and research. / Communication Science / D. Litt. et Phil.

Cette thèse porte sur des aspects structuraux et algorithmiques des graphes. Elle est divisée en deux parties, qui comportent deux études différentes : une partie sur des algorithmes centralisés-séquentiels, et une autre sur des algorithmes distribués. Dans la première partie, on étudie des aspects algorithmiques de deux structures de graphes appelés séparateurs minimaux et cliques maximales potentielles. Ces deux objets sont au coeur d'un méta-théorème dû à Fomin, Todinca and Villanger (SIAM J. Comput. 2015), qui affirme qu'une grande famille des problèmes d'optimisation peut être résolue en temps polynomial, si le graphe d'entrée contient un nombre polynomial de séparateurs minimaux. La contribution de cette partie consiste à prolonger le méta-théorème de Fomin et al. de deux manières : d'un côté, on l'adapte pour qu'il soit valide pour une plus grande famille des problèmes ; de l'autre, on étend ces résultats à des version paramétrées, pour certains paramètres des graphes. La deuxième partie de la thèse correspond à une étude du modèle appelé « Diffusion dans une Clique Congestionnée ». Dans ce modèle, les sommets d'un graphe communiquent entre eux dans des rondes synchrones, en diffusant un message de petite taille, visible par tout autre sommet. L'objectif ici est d'élaborer des protocoles qui reconnaissent des classes de graphes, en minimisant la taille des messages et le nombre de rondes. La contribution de cette partie est l'étude du rôle du hasard dans ce modèle, et la conception de protocoles pour la reconnaissance et la reconstruction des certaines classes des graphes. / This thesis is about structural and algorithmic aspects of graphs. It is divided in two parts, which are about two different studies: one part is about centralized-sequential algorithms, and the other part is about distributed algorithms. In the first part of the thesis we study algorithmic applications of two graph structures called minimal separators and potential maximal cliques. These two objects are in the core of a meta-theorem due to Fomin, Todinca and Villanger (SIAM J. Comput. 2015), which states that a large family of graph optimization problems can be solved in polynomial time, when the input is restricted to the family of graphs with polynomially many minimal separators. The contribution of this part of the thesis is to extend the meta-theorem of Fomin et al. in two ways. On one hand, we adapt it to be valid into a larger family of problems. On the other hand, we extend it into a parameterized version, for several graph parameters. In the second part of this thesis we study the broadcast congested clique model. In this model, the nodes of a graph communicate in synchronous rounds, broadcasting a message of small size visible to every other node. The goal is to design protocols that recognize graph classes minimizing the number of rounds and the message sizes. The contribution of this part is to explore the role of randomness on this model, and provide protocols for the recognition and reconstruction of some graph classes.

This research had the objective of describing from the perceptive-auditory view point the segmental characteristics (vowels and consonants) of the TV broadcast in four brazilian capitals (Rio de Janeiro, São Paulo, Recife and Maceió), in spontaneous and professional emission. This study was carried out in the Central Globo of Journalism Station in São Paulo - SP, Rio de Janeiro - RJ and Recife- PE, and the afiliated Rede Globo in Maceió - AL. The sample was composed by four TV broadcasters of each city researched. To evaluate the spontaneous emission, it was used conversations about the personal experiences provoking moments of informal conversation.To the professional emission, it was asked to the reporters to read a standard text, simulating the narrating style of the TV broadcast. The text structured to be read in professional emission had as objective cover the main phenomenon as potencially diferentiators of different accents. Such phenomenun could be summarized like that: a) the variations of /S/ and of /R/ pos-vocalic; b) alveolar oclusive consonant behaviour /t/ and /d/ before /i/; c) the vocalic contrast /e/ - /  / and /o/ - /  / in pretonic syllables; and, d) the optional vocalic nasality. For perceptive-auditory analyse was carried out a phonetics transcription of all material recorded using IPA. The results of this research in spontaneous emission can divide the speakers into two groups: Northeast (Recife and Maceió) and Southeast (São Paulo and Rio de Janeiro), characterizing them: the Northeast group for the use of alveolar oclusive variable - [ t] and [ d ] before / i /, for the realization of the open vowels in pretonic position and for the use of optional nasality in pretonic position. The Southeast group, for the use of palatized variable - [t] and [d] before the / i /, for the realization of the closed vowels in pretonic position and for the use of the optional nasality in tonic position. The reporters and TV presenters from Rio de Janeiro, Recife and Maceió modified their pronunciation of origin in the professional speech, but in the spontaneous emission there was a " relaxation" in keeping the broadcasting standard. The TV broadcasters from São Paulo city kept on average the segmental characteristics of the spontaneous speech and the professional speech. / Esta pesquisa teve como objetivo descrever do ponto de vista perceptivo-auditivo as características segmentais (vogais e consoantes) da fala de telejornalistas de quatro capitais brasileiras (Rio de Janeiro, São Paulo, Recife e Maceió), em emissão espontânea e profissional. Este estudo foi realizado nas emissoras da Central Globo de Jornalismo de São Paulo-SP, Rio de Janeiro-RJ e Recife-PE, e na afiliada da Rede Globo de Maceió- AL. A amostra foi composta por quatro telejornalistas de cada cidade pesquisada. Para avaliar a emissão espontânea, foi utilizada conversa sobre experiências pessoais provocando momentos de fala informal. Para a emissão profissional, foi solicitado que os repórteres lessem um texto padrão, simulando o estilo de narração do telejornalismo. O texto estruturado para ser lido em emissão profissional teve como objetivo cobrir os principais fenômenos como potencialmente diferenciadores dos diversos sotaques. Tais fenômenos podem ser assim sumarizados: a) as variações do /S/ e do /R/ pós-vocálico; b) comportamento das consoantes oclusivas alveolares /t/ e /d/ antes de /i/; c) os contrastes vocálicos /e/-// e /o/-//nas sílabas pretônicas; e, d) a nasalidade vocálica optativa. Para análise perceptivo-auditiva foi realizada a transcrição fonética de todo o material gravado, utilizando o IPA. Os resultados desta pesquisa, em emissão espontânea, podem dividir os falantes em dois grupos: Nordeste (Recife e Maceió) e Sudeste (São Paulo e Rio de Janeiro), caracterizando-os: o grupo do Nordeste pelo uso das variantes oclusivas alveolares -[t] e [d] diante de /i/, pela realização das vogais abertas em posição pretônica e pelo uso da nasalidade optativa em posição pretônica. O grupo do Sudeste, pelo uso das variantes palatalizadas -[t] e [d]diante de /i/, pela realização das vogais fechadas em posição pretônica e pelo uso da nasalidade optativa em posição tônica. Os repórteres e apresentadores das cidades do Rio de Janeiro, Recife e Maceió modificaram suas pronúncias de origem na fala profissional, já em emissão espontânea, houve um despoliciamento em manter o padrão telejornalístico. Os telejornalistas da cidade de São Paulo mantiveram em média as características segmentais da fala espontânea idênticas a da fala profissional.

Made available in DSpace on 2016-08-03T12:31:02Z (GMT). No. of bitstreams: 1 Janine Marques Passini.pdf: 627131 bytes, checksum: 656e95496b517efa100b6caf3c660279 (MD5) Previous issue date: 2009-06-10 / This thesis is part of the mass communication field of knowledge. The focus is within media studies and the goal is to create a new classification strategy for journalistic genres on Brazilian radio. The method for this study begins with an analysis of current literature on the subject from which classification categories were defined. These categories were then applied to the actual content of three programs on Radio Eldorado AM Sao Paulo, one of the most traditional journalistic broadcasters in Brazil.(AU) / A tese de doutorado insere-se no âmbito da Processos Comunicacionais, tendo como projeto temático a Midiologia Comparada. Tem como objetivo propor uma nova classificação para os gêneros radiojornalísticos, a partir do levantamento e da análise comparativa da bibliografia existente sobre o tema, confrontando-a posteriormente com a programação efetiva de três programas de uma das mais tradicionais emissoras segmentadas em jornalismo de São Paulo: a Rádio Eldorado AM. Quanto à metodologia, primeiramente efetuamos uma análise de conteúdo, a fim de compreender a utilização de tais formatos dentro de gêneros estabelecidos e, assim, propor uma nova classificação dos gêneros jornalísticos brasileiros no rádio, conforme o objetivo geral deste estudo. Num segundo momento realizamos o levantamento da ocorrência dos formatos jornalísticos nos três programas radiofônicos analisados. Ao final, concluímos que os gêneros radiojornalísticos não têm sido bem explorados pelos veículos ditos all news e talk and news.(AU)

Cette thèse porte sur la transmission d'informations dans les réseaux d'ordinateurs. Nous nous sommes plus particulièrement penchés sur deux aspects de ce problème : les communications anonymes sur Internet en présence de nœuds rationnels (aussi appelés “égoïstes") et la diffusion à ordre uniformément total dans le cadre d'une grappe de machines. Concernant le premier aspect, nous avons constaté qu'il n'existait pas de protocole de communications anonymes fonctionnant en présence de nœuds rationnels et capable de monter en charge (c'est à dire de fonctionner efficacement en présence d'un grand nombre de noeuds). Nous avons donc proposé RAC, le premier protocole de communications anonymes capable de monter en charge et fonctionnant en présence de nœuds rationnels. Concernant le deuxième aspect, nous avons constaté qu'il n'existait pas de protocole de diffusion à ordre uniformément total assurant à la fois un débit optimal et une latence faible. Nous avons donc proposé FastCast, le premier protocole de diffusion à ordre uniformément total garantissant un débit optimal tout en assurant une latence faible. / This theses focuses on information dissemination in computer networks. We study two aspects of this topic : anonymous communication on Internet in presence of rational nodes and uniform total order broadcast in a computer cluster. Concerning the first aspect, we observed that no anonymous communication protocol is capable of working in presence of rational nodes while scaling existed. Therefore, we proposed RAC, the first anonymous communication protocol functioning in presence of rational nodes and able of scaling. Concerning the second aspect, we observed that no existing uniform total order broadcast protocol is capable of ensuring both a good latency and an optimal throughput. In order to fill this lack we proposed FastCast, the first uniform total order

Submitted by Livia Mello (liviacmello@yahoo.com.br) on 2016-10-11T12:53:34Z No. of bitstreams: 1 DissGP.pdf: 3871361 bytes, checksum: c4eb98e6e25b2a04f1bcac332cd9177e (MD5) / Approved for entry into archive by Ronildo Prado (ronisp@ufscar.br) on 2016-10-17T13:32:21Z (GMT) No. of bitstreams: 1 DissGP.pdf: 3871361 bytes, checksum: c4eb98e6e25b2a04f1bcac332cd9177e (MD5) / Approved for entry into archive by Ronildo Prado (ronisp@ufscar.br) on 2016-10-17T13:32:46Z (GMT) No. of bitstreams: 1 DissGP.pdf: 3871361 bytes, checksum: c4eb98e6e25b2a04f1bcac332cd9177e (MD5) / Made available in DSpace on 2016-10-17T13:39:08Z (GMT). No. of bitstreams: 1 DissGP.pdf: 3871361 bytes, checksum: c4eb98e6e25b2a04f1bcac332cd9177e (MD5) Previous issue date: 2015-06-24 / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / Religion is a phenomenon with a significant presence in brazilian society, whose manifestations have increased and diversified. Developments such as broadcast television, radio and internet make most churches, including the Catolic do not establish themselves solely on their physical structure in the quest for more followers. There is a set of social and economic relations involved in this process. The vast networks of interconnected individuals in the media range from members of the clergy to laymen volunteers, employees and mediatic businesses entrepreneurs. Resulting from research supported by FAPESP underway on changes in Brazilian Christianity, this dissertation turns to the analysis of the Catholic television station Rede Vida in its performance as a media, economic enterprise and also religious. Aimed at the study of social relationships underlying the business and commercial aspects of this station and what it represents in the Brazilian religious market. / A religião ainda é um fenômeno com significativa presença na sociedade brasileira, cujas formas de manifestação aumentaram e se diversificaram. Empreendimentos como emissoras de televisão, rádio e provedores de internet fazem com que a maioria das igrejas, inclusive a católica, não se estabeleça somente em sua estrutura física na busca por mais adeptos. Há um conjunto de relações sociais e econômicas envolvidas nesse processo. As amplas redes de indivíduos interligados na comunicação social compreendem desde os membros do clero até leigos, voluntários, funcionários e empresários condutores de negócios midiáticos. Decorrente de uma pesquisa apoiada pela FAPESP sobre mudanças no cristianismo brasileiro, esta dissertação se volta para a análise da emissora televisiva católica Rede Vida em sua atuação como um empreendimento econômico-midiático e também religioso. Visa o estudo das relações sociais imbricadas nos aspectos comerciais e empresariais dessa emissora e o que isso representa no mercado religioso brasileiro.

This thesis describes the process of archiving of shots and programmes in news and sport editorial offices of the Czech Television. Newsroom prepares broadcasts for ČT1 and ČT24 programmes. The sport editorial office provides the broadcasts for ČT SPORT and also prepares the news for "Branky, body, vteřiny" on ČT1. With regard to this, both offices produce a considerable amount of audio-visual material. The thesis examines how this material is subsequently archived. Do both offices have a systematic and comprehensive procedure for archiving of shots and programmes? And are these archives easily traceable, available and usable for further broadcasting? The thesis summarizes the history of archiving of news and sport audio-visual material. The key process of digitization, which allows the transcription and saving of old archive materials stored on tape media, is also mentioned. After describing the history of archiving, the author focuses on the current methodology of the process and describes the system of archiving in news and sports news. Who does archiving and what systems and programmes are used for it? At the end of this thesis the future of archiving is analysed with regard to the progress in technologies used for archiving.