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Radiorreportagem: referências para a prática, o ensino e a pesquisa; Broadcast journalism: references to practice, teaching and research

Lopes, Nadini de Almeida
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 19/09/2013 Português
Relevância na Pesquisa
37.1%
Com a crescente transformação no campo tecnológico, o jornalista é imerso diariamente em novos desafios que mudam não somente a forma de pensamento, mas também o fazer da profissão. No radiojornalismo, esse percurso deve ser avaliado com cuidado. Primeiramente é importante desconstruir a ideia de ascensão e queda desse meio de comunicação a cada novidade que surge. A radiorreportagem pode ser vista como a mais importante das atividades do repórter de rádio. Esse deve ser o momento em que ele prepara para o ouvinte um material rico em sons ambientes para que ele seja facilmente transportado para a cena relatada. Porém, muitas mudanças ocorrem na sociedade contemporânea e transformam essa relação, sendo uma das principais o conceito de convergência das mídias que resignifica a compreensão da radiorreportagem e o papel do repórter de rádio. Doze entrevistados acadêmicos e profissionais foram ouvidos e teceram uma análise sobre os principais pontos de discussão ao redor desse tema: o conceito de radiorreportagem, a evolução dos aparatos técnicos, convergência das mídias e internet, a importância da linguagem radiofônica e o ensino de radiojornalismo nos bancos das universidades buscando auxiliar os profissionais da área de rádio quanto à prática...

Um domingo qualquer - estratégias de grade de programação de televisão aberta no Brasil; Any Given Sunday: Broadcast Brazilian TV Programming Strategies. São Paulo, 2013. Dissertation

Erthal, Claudia
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 26/06/2013 Português
Relevância na Pesquisa
36.75%
Pesquisa em Comunicação na área de Meios de Processos Audiovisuais que estuda as estratégias de grade de programação de domingo na TV aberta brasileira. Ênfase no domingo em virtude de ser o dia com maior número de telespectadores ligados e por ser um dos dias com maior visibilidade dos produtos veiculados. As principais linhas teóricas utilizadas na interpretação da pesquisa tratam da formação do hábito de ver televisão, do contrato afetivo entre o fluxo da grade de programação e o telespectador e do Princípio da Razão Durante através da teoria do Metáporo. Texto multidisciplinar que reúne teóricos de Comunicação, Estudo de TV, Estudos Culturais, Sociologia, Filosofia para construir um corpo teórico que trata de entender estratégias utilizadas pelas emissoras para montar a grade de programação e de como a grade se torna um específico da TV, um produto audiovisual único e fluído e uma forma discursiva estratégica das empresas de comunicação.; Research in Communication within the Audiovisual Media Process area focused on the broadcast Sunday Brazilian TV programming strategies. It emphasizes the Sunday programming due to be the day with the largest number of viewers watching TV and due to one of the days that gets more visibility to the media products and production. The main theoretical lines used in the research are about the habit of watching TV...

Multicast/broadcast network convergence in next generation mobile networks

Santos, Justino; Gomes, Diogo; Sargento, Susana; Aguiar, Rui Luis; Baker, Nigel; Zafar, Madiha; Ikram, Ahsan
Fonte: Elsevier Publicador: Elsevier
Tipo: Artigo de Revista Científica
Português
Relevância na Pesquisa
36.98%
The 3GPP Multimedia Broadcast Multicast Service (MBMS) aims to introduce group communications into the 3G networks. One of the current key challenges is how to evolve these incipient features towards the "beyond 3G vision" of a converged global network where multimedia content can be delivered over one or more selected broadcast transport bearers. This paper presents potential multicast/broadcast technologies convergence and discusses the issues and challenges in moving towards this next generation network vision from the viewpoint of evolving MBMS. (C) 2007 Elsevier B.V. All rights reserved.

Authenticated file broadcast protocol

Reis, Simão; Zúquete, André; Faneca, Carlos; Vieira, José
Fonte: Springer International Publishing Publicador: Springer International Publishing
Tipo: Parte de Livro
Português
Relevância na Pesquisa
36.89%
The File Broadcast Protocol (FBP) was developed as a part of the DETIboot system. DETIboot allows a host to broadcast an operating system image through an 802.11 wireless network to an arbitrary number of receivers. Receivers can load the image and immediately boot a Linux live session. The initial version of FBP had no security mechanisms. In this paper we present an authentication protocol developed for FBP that ensures a correct file distribution from the intended source to the receivers. The performance valuations have shown that, with the best operational configuration tested, the file download time is increased by less than 5%.

HyParView: a membership protocol for reliable gossip-based broadcast

Leitão, João; Pereira, José; Rodrigues, Luís
Fonte: Department of Informatics, University of Lisbon Publicador: Department of Informatics, University of Lisbon
Tipo: Relatório
Publicado em /05/2007 Português
Relevância na Pesquisa
36.89%
Gossip, or epidemic, protocols have emerged as a powerful strategy to implement highly scalable and resilient reliable broadcast primitives. Due to scalability reasons, each participant in a gossip protocol maintains a partial view of the system. The reliability of the gossip protocol depends upon some critical properties of these views, such as degree distribution and clustering coefficient. Several algorithms have been proposed to maintain partial views for gossip protocols. In this paper, we show that under a high number of faults, these algorithms take a long time to restore the desirable view properties. To address this problem, we present HyParView, a new membership protocol to support gossip-based broadcast that ensures high levels of reliability even in the presence of high rates of node failure. The HyParView protocol is based on a novel approach that relies in the use of two distinct partial views, which are maintained with different goals by different strategies

Epidemic Broadcast Trees

Leitão, João; Pereira, José; Rodrigues, Luís
Fonte: Department of Informatics, University of Lisbon Publicador: Department of Informatics, University of Lisbon
Tipo: Relatório
Publicado em /05/2007 Português
Relevância na Pesquisa
36.98%
There is an inherent trade-off between epidemic and deterministic tree-based broadcast primitives. Tree-based approaches have a small message complexity in steady-state but are very fragile in the presence of faults. Gossip, or epidemic, protocols have a higher message complexity but also offer much higher resilience. This paper proposes an integrated broadcast scheme that combines both approaches. We use a low cost scheme to build and maintain broadcast trees embedded on a gossip-based overlay. The protocol sends the message payload preferably via tree branches but uses the remaining links of the gossip overlay for fast recovery and expedite tree healing. Experimental evaluation presented in the paper shows that our new strategy has a low overhead and that is able to support large number of faults while maintaining a high reliability

Atomic Broadcast in Asynchronous Crash-Recovery Distributed Systems

Rodrigues, Luís; Raynal, Michel
Fonte: Department of Informatics, University of Lisbon Publicador: Department of Informatics, University of Lisbon
Tipo: Relatório
Publicado em /11/1999 Português
Relevância na Pesquisa
37.05%
Atomic Broadcast is a fundamental problem of distributed systems: it states that messages must be delivered in the same order to their destination processes. This paper describes a solution to this problem in asynchronous distributed systems in which processes can crash and recover. A Consensus-based solution to Atomic Broadcast problem has been designed by Chandra and Toueg for asynchronous distributed systems where crashed processes do not recover. Although our solution is based on different algorithmic principles, it follows the same approach: it transforms any Consensus protocol suited to the crash-recovery model into an Atomic Broadcast protocol suited to the same model. We show that Atomic Broadcast can be implemented without requiring any additional log operations in excess of those required by the Consensus. The paper also discusses how additional log operations can improve the protocol in terms of faster recovery and better throughput. It is interesting to note that our work benefits from recent results in the study of the Consensus problem in the crash-recovery model

Atomic Broadcast and Quorum-based Replication in Asynchronous Crash-Recovery Distributed Systems

Rodrigues, Luís; Raynal, Michel
Fonte: Department of Informatics, University of Lisbon Publicador: Department of Informatics, University of Lisbon
Tipo: Relatório
Publicado em /01/1999 Português
Relevância na Pesquisa
36.98%
This paper describes a solution to the Atomic Broadcast problem in asynchronous distributed systems in which processes can crash and recover. Our solution is based on a transformation of any Consensus algorithm into an Atomic Broadcast algorithm. Thus, our work can benefit from recent results in the study of the Consensus problem in the crash-recovery model. The paper also shows how to extend the Atomic Broadcast primitive to support the implementation of Quorum-based replica management in crash-recovery systems. The proposed technique makes a bridge between established results on Weighted Voting and recent results on the Consensus problem.

Efeito da semeadura a lanço e da população de plantas no rendimento de grãos e outras características da soja [Glycine max (L.) Merrill]; Effect of broadcast seeding and plant density in the grains yield and other characteristics of soybean [Glycine Max (L.) Merrill]

Fonte: Universidade Federal de Lavras Publicador: Universidade Federal de Lavras
Tipo: Artigo de Revista Científica
Português
Relevância na Pesquisa
36.89%
The search of new alternatives in the sense of increasing the soybean productivity has been several research objective. With that intection, a trial was conduced at the farmer Canadá, in Jussara (GO), in a Dark Red Latosol soil, utilized two sowing systems (broacast and furrows), plants populations (200, 300, 400, 500, 600 and 700.000 plants.ha-1) in blocks casualized design with tree replications and factorial scheme (2x6). The portion were constituted of 4 row spacing of 0,50 m with useful area of 4,0 m2 in the system of sowing in furrows same area for the broadcast system. The use of the sowing broadcast system it provided increase in the grains yields of 35,33% (1128 kg.ha-1) in comparison with of the furrow. The populations altered yield grains significantly with prominence for 4000.000 plants.ha-1 wich presented also logding smaller.

Network coding based wireless broadcast with performance guarantee

Wang, Peng; Mao, Guoqiang; Lin, Zihuai; Ge, Xiaohu; Anderson, Brian D. O.
Fonte: Institute of Electrical and Electronics Engineers (IEEE) Publicador: Institute of Electrical and Electronics Engineers (IEEE)
Tipo: Artigo de Revista Científica Formato: 13 pages
Português
Relevância na Pesquisa
37.14%
Wireless broadcast has been increasingly used to deliver information of common interest to a large number of users. There are two major challenges in wireless broadcast: the unreliable nature of wireless links and the difficulty of acknowledging the correct reception of every broadcast packet by every user when the number of users becomes large. In this paper, by resorting to stochastic geometry analysis, we develop a network coding based broadcast scheme that allows a base station (BS) to broadcast a given number of packets to a large number of users, without user acknowledgment, while being able to provide a performance guarantee on the probability of successful delivery. Further, the BS only has limited statistical information about the environment including the spatial distribution of users (instead of their exact locations and number) and the wireless propagation model. Performance analysis is conducted. On that basis, an upper and a lower bound on the number of packet transmissions required to meet the performance guarantee are obtained. Simulations are conducted to validate the accuracy of the theoretical analysis. The technique and analysis developed in this paper are useful for designing efficient and reliable wireless broadcast strategies.

Air indexing for on-demand XML data broadcast

Sun, W.; Qin, Y.; Wu, J.; Zheng, B.; Zhang, Z.; Yu, P.; Liu, P.; Zhang, J.
Fonte: IEEE Publicador: IEEE
Tipo: Artigo de Revista Científica
Publicado em //2014 Português
Relevância na Pesquisa
36.98%
XML data broadcast is an efficient way to disseminate semistructured information in wireless mobile environments. In this paper, we propose a novel two-tier index structure to facilitate the access of XML document in an on-demand broadcast system. It provides the clients with an overall image of all the XML documents available at the server side and hence enables the clients to locate complete result sets accordingly. A pruning strategy is developed to cut down the index size and a two-tier structure is proposed to further remove any redundant information. In addition, two index distribution strategies, namely naive distribution and partial distribution, have been designed to interleave the index information with the XML documents in the wireless channels. Theoretical analysis and simulation experiments are also put forward to show the benefits of our indexing methods.

Scheduling parallel data retrievals for non-consecutive broadcast in MIMO wireless networks

He, P.; Shen, H.; Tian, H.
Fonte: IEEE Publicador: IEEE
Tipo: Conference paper
Publicado em //2012 Português
Relevância na Pesquisa
36.98%
Wireless data broadcast is usually used to disseminate the public information to considerable clients in wireless environment. Based on the development of mobile device, some mobile devices can simultaneously use multiple antennae to process some operations. In this paper, we commit to study data retrieval scheduling problem in wireless data broadcast, which mobile device has multiple antennae and the data items are non-consecutively broadcasted in multiple parallel channels. In order to improve the performance of downloading requested data items, we propose a scheme of scheduling parallel data retrievals for non-consecutive broadcast to decrease access latency and energy consumption. In this scheme, we utilize a weight of channel through two balancing factors to choose the suitable channel for data retrieval. We analyze the performance of proposed scheme and the other schemes. Evaluation results prove that the proposed scheme has the better performance.; Ping He, Hong Shen and Hui Tian

Broadcast Detection Structures with Applications to Sensor Networks; Distributed Structures, Sequential Optimization, and Quantization for Detection

Johnson, Don; Lexa, Michael; Lexa, Michael; Johnson, Don
Fonte: Universidade Rice Publicador: Universidade Rice
Tipo: Artigo de Revista Científica
Português
Relevância na Pesquisa
37.05%
Journal Paper. Earliest preprint of article is entitled, "Broadcast Detection Structures with Applications to Sensor Networks" (filename Lex2006Mar1BroadcastD.PDF). The version that was accepted and is to appear in the IEEE Transactions of Signal Processing is now titled, "Distributed Structures, Sequential Optimization, and Quantization for Detection" (filename posted_preprint_broadcast_mal2007.pdf).; Data broadcasting is potentially an effective and efficient way to share information in wireless sensor networks. Broadcasts offer energy savings over multiple, directed transmissions, and they provide a vehicle to exploit the statistical dependencies often present in distributed data. In this paper, we examine two broadcast structures in the context of a distributed detection problem whose inputs are statistically dependent. Specifically, we develop a suboptimal approach to maximize the Kullback-Leibler divergence over a set of binary quantization rules. Our approach not only leads to simple parameterizations of the quantization rules in terms of likelihood ratio thresholds, but also provides insight into the inherent constraints distributed structures impose. We then present two examples in detail and compare the performance of the broadcast structures to that of a centralized system and a noncooperative system. These examples suggest that in situations where the detection problem is difficult (small input divergence)...

Broadcast cancellation in search mechanisms

Lima, R.; Baquero, Carlos; Miranda, Hugo
Fonte: ACM Publicador: ACM
Tipo: Conferência ou Objeto de Conferência
Publicado em 18/03/2013 Português
Relevância na Pesquisa
36.98%
Searching for resources over unstructured networks is usually supported by broadcast communication primitives. Ideally, the broadcast process should be cancelled as soon as possible after a successful discovery, to avoid ooding the entire network. However, cancelling an ongoing broadcast is challenging and may increase the number of exchanged messages. In this paper, we compare the cancellation mechanisms used by BERS and BERS? With new proposed cancellation approaches BCIR and BCIR? The formulation of a simplified analytical model and the simulation results show that:i)it is possible to reduce the number of retransmitted messages, without increasing the latency observed in BERS?; and ii) BCIR is more energy eficient, which can contribute to extend the availability of mobile battery powered devices.; Fundação para a Ciência e Tecnologia, Portugal (PEst- OE/EME/UI4005/2011) and carried out within the research Centro Lusíada de Investigação e Desenvolvimento em Engenharia e Gestão Industrial (CLEGI)

Direct broadcast technology in Bosnia: its impact on the decision making process and joint endeavor operations

Morrill, Robert D
Fonte: Monterey, California. Naval Postgraduate School Publicador: Monterey, California. Naval Postgraduate School
Português
Relevância na Pesquisa
37.17%
Approved for public release; distribution is unlimited; During DESERT STORM a serious shortfall was identified in the communications architecture and its ability to effectively provide high bandwidth information to meet the demands of the operation. In response to this shortfall, the Department of Defense (DoD) is pursuing the exploitation of commercial Direct Broadcast Satellite (DBS) technology and its ability to broadcast video and data at high rates to small, affordable, and portable terminals. The Global Broadcast Service (GBS) was initiated to ultimately provide this military direct broadcast capability. A precursor to GBS, the Joint Broadcast Service (JBS), was begun as an Advanced Concept Technology Demonstration (ACTD). It is now leveraging DBS technology to support Operation JOINT ENDEAVOR This thesis describes how the JBS works, what types of information are sent over the JBS, the complete process of information distribution, and the impact the JBS has had on Operation JOINT ENDEAVOR and the associated operational decision making process. The JBS system has, at least in part, answered the joint warfighter's need for an improved high bandwidth video and data distribution system. Although it does have force enhancement capabilities...

Coordenação de Agentes Móveis através do Canal de Broadcast; Coordination of Mobile Agents through the Broadcast Channel

Nagamuta, Vera
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 19/11/1999 Português
Relevância na Pesquisa
37.1%
Em aplicações distribuídas baseadas em agentes móveis, a coordenação das ações dos agentes móveis é uma tarefa complexa. A maior dificuldade é devido ao fato que agentes móveis podem mudar de endereço dinamicamente. Nesta dissertação, apresentamos o projeto e a implementação de um mecanismo de coordenação de agentes móveis que contorna este problema. Este mecanismo, que chamamos de Canal de Broadcast, está baseado na difusão de mensagens e possibilita que os membros de um grupo de agentes móveis interajam entre si, independentemente de suas localizações correntes. Modelos de coordenação existentes oferecem formas de interação entre agentes móveis, mas todos eles impõem alguma exigência. Ou os agentes móveis devem conhecer a localização de outros agentes, ou devem estar localizados no mesmo lugar ou devem migrar para um lugar específico. A principal vantagem deste mecanismo de coordenação está na total transparência de localização: as mensagens podem ser endereçadas a um conjunto de agentes móveis independentemente de sua localização corrente. Este mecanismo foi implementado no ASDK (Aglets Software Development Kit) da IBM e a sua utilidade foi demonstrada usando dois problemas típicos de coordenação em Sistemas Distribuídos: a Exclusão Mútua e o protocolo Manager-Workers. Testamos o desempenho do mecanismo e identificamos que o custo do Canal de Broadcast não é tão alto comparado aos benefícios que proporciona. Através deste mecanismo...

Protocolo de difusão síncrona totalmente ordenada para aglomerados de alto desempenho; Synchronous total order broadcast protocol for high performance clusters

Daniel Cason
Fonte: Biblioteca Digital da Unicamp Publicador: Biblioteca Digital da Unicamp
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 28/02/2013 Português
Relevância na Pesquisa
37.05%
Protocolos de Difusão Totalmente Ordenada (DTO) constituem o núcleo de diversas soluções que dão suporte ao desenvolvimento de aplicações distribuídas tolerantes a falhas. O longo período no qual este problema vem sendo objeto de pesquisa e a quantidade de algoritmos que foram para ele propostos atestam, não só a sua importância, mas também a dificuldade de se obter soluções eficientes para DTO. Este trabalho apresenta um novo algoritmo de DTO, que explora a sincronia e a confiabilidade inerentes ao ambiente dos aglomerados ou clusters de alto desempenho para construir uma solução bastante simples de Difusão Totalmente Ordenada, cujo desempenho experimental mostrou-se comparável ao obtido por soluções de DTO projetadas para modelos assíncronos de computação. O protocolo proposto destina-se ao modelo assíncrono temporizado de computação, aumentado com um mecanismo simples, baseado na difusão de pulsos, para sincronizá-la a execução dos processos. A hipótese que sustenta este mecanismo de sincronização é que os aglomerados modernos, dado que se controle a carga a eles aplicada, podem executar por períodos razoavelmente longos sem que ocorram falhas de processos e apresentando um comportamento bastante similar ao de sistemas síncronos. Dada esta hipótese...

ADC : ambiente para experimentação e avaliação de protocolos de difusão confiável; Reliable broadcast protocols experimentation and evaluation environment (ADC)

Barcelos, Patricia Pitthan de Araujo
Fonte: Universidade Federal do Rio Grande do Sul Publicador: Universidade Federal do Rio Grande do Sul
Tipo: Dissertação Formato: application/pdf
Português
Relevância na Pesquisa
37.23%
Uma tendência recente em sistemas de computação é distribuir a computação entre diversos processadores físicos. Isto conduz a dois tipos de sistemas: sistemas fortemente acoplados e sistemas fracamente acoplados. Este trabalho enfoca os sistemas de computação classificados como fracamente acoplados, ou sistemas distribuídos, como são popularmente conhecidos. Um sistema distribuído, segundo [BAB 86], pode ser definido como um conjunto de processadores autônomos que não compartilham memória, não tem acesso a clocks' globais e cuja comunicação é realizada somente por troca de mensagens. As exigências intrínsecas de sistemas distribuídos compreendem a confiabilidade e a disponibilidade. Estas exigências tem levado a um crescente interesse em técnicas de tolerância a falhas, cujo objetivo é manter a consistência do sistema distribuído, mesmo na ocorrência de falhas. Uma técnica de tolerância a falhas amplamente utilizada em sistemas distribuídos é a técnica de difusão confiável. A difusão confiável é uma técnica de redundância de software, onde um processador dissemina um valor para os demais processadores em um sistema distribuído, o qual esta sujeito a falhas [BAB 85]. Por ser uma técnica básica de comunicação...

Constructing minimum-energy broadcast trees in wireless ad hoc networks.

Liang, Weifa
Fonte: Association for Computing Machinery Inc (ACM) Publicador: Association for Computing Machinery Inc (ACM)
Tipo: Conference paper
Português
Relevância na Pesquisa
37.14%
In this paper we assume that a multihop wireless network (also called a wireless ad hoc network) consists of nodes whose transmitting powers are finitely adjustable. We consider two fundamental problems related to power consumption in this kind of network. One is the minimum-energy broadcast tree problem, which broadcast a message from a source node to all the other nodes in the network such that the summation of transmission powers at all nodes is minimized; and another is the minimum-energy multicast tree problem, which multicasts a message from a source node to the nodes in a given subset of nodes such that the summation of the transmission powers at all involved nodes is minimized. We first show the minimum-energy broadcast tree problem is NP-complete. We then present an approximate algorithm for the problem in a general setting, which delivers an approximate solution with a bounded performance guarantee. The algorithm takes O((k + 1)1/εn3/ε) time, where n is the number of nodes in the wireless network, κ is the number of power levels at each node, and ε is constant with 0 < ε ≤ 1. For a special case of the problem where every node is equipped with the same type of battery, we propose an approximate algorithm which has a better performance ratio than that in the general case setting...

Supporting range queries in a wireless environment with nonuniform broadcast

Tan, Kian-Lee; Yu, Jun X; Eng, Pin-Kwang
Fonte: Elsevier Publicador: Elsevier
Tipo: Artigo de Revista Científica
Português
Relevância na Pesquisa
37.14%
In a wireless computing environment, a server disseminates information by periodically broadcasting data on 'air', while clients 'catch' their desired data on the fly. To determine the data to be broadcast, the server constructs a broadcast program. While a nonuniform broadcast program has been demonstrated to be effective in reducing the average access times for single-record retrievals, existing nonuniform broadcast programs perform poorly for range queries. In this paper, we propose a new algorithm to generate nonuniform broadcast programs that can facilitate range queries. Our algorithm supports selective tuning using the flexible indexing scheme. We conducted an extensive simulation study, and our results show that the proposed algorithm can generate programs that lead to significant improvement (in terms of both access time and tuning time) for range queries without sacrificing much on the performance of single object retrievals.