998 resultados para O senhor dos anéis - Tradução


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Dissertação apresentada à Escola Superior de Educação de Lisboa para obtenção de grau de mestre em Educação Especial, domínio Cognição e Multideficiência

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OBJETIVO: Realizar adaptação cultural para versão brasileira do questionário de atividade física no tempo de lazer e avaliar a validade de conteúdo, praticabilidade, aceitabilidade e confiabilidade.MÉTODOS: Foram realizadas as etapas de tradução, síntese, retrotradução, avaliação por comitê de especialistas e pré-teste, seguidos pela avaliação da praticabilidade, aceitabilidade e confiabilidade (teste-reteste). Os juízes avaliaram as equivalências semântico-idiomática, conceitual, cultural e metabólica. A versão adaptada foi submetida ao pré-teste (n = 20) e teste-reteste (n = 80) em indivíduos saudáveis e pacientes com doenças cardiovasculares, em Limeira, SP, entre 2010 e 2011. A proporção de concordância do comitê de juízes foi quantificada por meio do Índice de Validade de Conteúdo. A confiabilidade foi avaliada segundo critério de estabilidade, com intervalo de 15 dias entre as aplicações, a praticabilidade pelo tempo gasto na entrevista e a aceitabilidade pelo percentual de itens não respondidos e proporção de pacientes que responderam a todos os itens.RESULTADOS: A versão traduzida do questionário apresentou equivalências semântico-idiomática, conceitual, cultural e metabólica adequadas, com substituição de algumas atividades físicas mais adequadas para a população brasileira. A análise da praticabilidade evidenciou curto tempo de aplicação do instrumento (média de 3,0 min). Quanto à aceitabilidade, todos os pacientes responderam a 100% dos itens. A análise do teste-reteste sugeriu estabilidade temporal do instrumento (Índice de Correlação Intraclasse = 0,84).CONCLUSÕES: A versão brasileira do questionário apresentou propriedades de medida satisfatórias. Recomenda-se sua aplicação a populações diversas em estudos futuros, a fim de disponibilizar propriedades de medida robustas.

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Secure group communication is a paradigm that primarily designates one-to-many communication security. The proposed works relevant to secure group communication have predominantly considered the whole network as being a single group managed by a central powerful node capable of supporting heavy communication, computation and storage cost. However, a typical Wireless Sensor Network (WSN) may contain several groups, and each one is maintained by a sensor node (the group controller) with constrained resources. Moreover, the previously proposed schemes require a multicast routing support to deliver the rekeying messages. Nevertheless, multicast routing can incur heavy storage and communication overheads in the case of a wireless sensor network. Due to these two major limitations, we have reckoned it necessary to propose a new secure group communication with a lightweight rekeying process. Our proposal overcomes the two limitations mentioned above, and can be applied to a homogeneous WSN with resource-constrained nodes with no need for a multicast routing support. Actually, the analysis and simulation results have clearly demonstrated that our scheme outperforms the previous well-known solutions.

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Stringent cost and energy constraints impose the use of low-cost and low-power radio transceivers in large-scale wireless sensor networks (WSNs). This fact, together with the harsh characteristics of the physical environment, requires a rigorous WSN design. Mechanisms for WSN deployment and topology control, MAC and routing, resource and mobility management, greatly depend on reliable link quality estimators (LQEs). This paper describes the RadiaLE framework, which enables the experimental assessment, design and optimization of LQEs. RadiaLE comprises (i) the hardware components of the WSN testbed and (ii) a software tool for setting-up and controlling the experiments, automating link measurements gathering through packets-statistics collection, and analyzing the collected data, allowing for LQEs evaluation. We also propose a methodology that allows (i) to properly set different types of links and different types of traffic, (ii) to collect rich link measurements, and (iii) to validate LQEs using a holistic and unified approach. To demonstrate the validity and usefulness of RadiaLE, we present two case studies: the characterization of low-power links and a comparison between six representative LQEs. We also extend the second study for evaluating the accuracy of the TOSSIM 2 channel model.

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Handoff processes, the events where mobile nodes select the best access point available to transfer data, have been well studied in cellular and WiFi networks. However, wireless sensor networks (WSN) pose a new set of challenges due to their simple low-power radio transceivers and constrained resources. This paper proposes smart-HOP, a handoff mechanism tailored for mobile WSN applications. This work provides two important contributions. First, it demonstrates the intrinsic relationship between handoffs and the transitional region. The evaluation shows that handoffs perform the best when operating in the transitional region, as opposed to operating in the more reliable connected region. Second, the results reveal that a proper fine tuning of the parameters, in the transitional region, can reduce handoff delays by two orders of magnitude, from seconds to tens of milliseconds.

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Securing group communication in wireless sensor networks has recently been extensively investigated. Many works have addressed this issue, and they have considered the grouping concept differently. In this paper, we consider a group as being a set of nodes sensing the same data type, and we alternatively propose an efficient secure group communication scheme guaranteeing secure group management and secure group key distribution. The proposed scheme (RiSeG) is based on a logical ring architecture, which permits to alleviate the group controller’s task in updating the group key. The proposed scheme also provides backward and forward secrecy, addresses the node compromise attack, and gives a solution to detect and eliminate the compromised nodes. The security analysis and performance evaluation show that the proposed scheme is secure, highly efficient, and lightweight. A comparison with the logical key hierarchy is preformed to prove the rekeying process efficiency of RiSeG. Finally, we present the implementation details of RiSeG on top of TelosB sensor nodes to demonstrate its feasibility.

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OBJETIVO: Construir a versão em Língua Brasileira de Sinais dos instrumentos WHOQOL-BREF e WHOQOL-DIS para avaliar a qualidade de vida da população surda brasileira.MÉTODOS: Utilizou-se metodologia proposta pela Organização Mundial da Saúde (WHOQOL-BREF e WHOQOL-DIS) para a construção dos instrumentos adaptados para população surda em Língua Brasileira de Sinais (Libras). A pesquisa para execução do instrumento consistiu de 13 etapas: 1) criação do sinal qualidade de vida; 2) desenvolvimento das escalas de respostas em Libras; 3) tradução por um grupo bilíngue; 4) versão reconciliadora; 5) primeira retrotradução; 6) produção da versão em Libras a ser disponibilizada aos grupos focais; 7) realização dos grupos focais; 8) revisão por um grupo monolíngue; 9) revisão pelo grupo bilíngue; 10) análise sintática/semântica e segunda retrotradução; 11) reavaliação da retrotradução pelo grupo bilíngue; 12) filmagem da versão para o software; 13) desenvolvimento do software WHOQOL-BREF e WHOQOL-DIS em Libras.RESULTADOS: Características peculiares da cultura da população surda apontaram a necessidade de adaptações na metodologia de aplicação de grupos focais quando compostos por pessoas surdas. As convenções ortográficas da escrita das línguas sinalizadas não estão consolidadas, o que trouxe dificuldades em registrar graficamente as etapas de tradução. As estruturas linguísticas que causaram maiores problemas de tradução foram as que incluíram expressões idiomáticas do português, muitas sem conceitos equivalentes entre o português e a Libras. Foi possível construir um software do WHOQOL-BREF e WHOQOL-DIS em Libras.CONCLUSÕES: O WHOQOL-BREF e o WHOQOL-DIS em Libras possibilitarão que os surdos se expressem autonomamente quanto a sua qualidade de vida, o que permitirá investigar com maior precisão essas questões.

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Radio link quality estimation in Wireless Sensor Networks (WSNs) has a fundamental impact on the network performance and also affects the design of higher-layer protocols. Therefore, for about a decade, it has been attracting a vast array of research works. Reported works on link quality estimation are typically based on different assumptions, consider different scenarios, and provide radically different (and sometimes contradictory) results. This article provides a comprehensive survey on related literature, covering the characteristics of low-power links, the fundamental concepts of link quality estimation in WSNs, a taxonomy of existing link quality estimators, and their performance analysis. To the best of our knowledge, this is the first survey tackling in detail link quality estimation in WSNs. We believe our efforts will serve as a reference to orient researchers and system designers in this area.

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This poster abstract presents smart-HOP, a reliable handoff mechanism for mobility support in Wireless Sensor Networks (WSNs). This technique relies on a fuzzy logic approach applied at two levels: the link quality estimation level and the access point selection level. We present the conceptual design of smart-HOP and then we discuss implementation requirements and challenges.

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In the southern part of Tagus basin, North of paleozoic rocks of Valverde-Senhor das Chagas (near Alcácer do Sal) horst, a marine transgression has been recognized, Upper Serravallian, and maybe Lower Tortonian in age. There are no earlier marine deposits, and no younger ones are known either. Paleozoic behaved as a barrier separating two basins, distinct at least since Middle Miocene until Upper Pleistocene. Until now, both were regarded as a single entity, the so-called «Sado basin» Southwards (Alvalade basin) there has been a single transgression. It was assummed that it was the same one as the former. Indeed it is not definitely so. Later transgression accounts for Esbarrondadoiro Formation, whose deposits have been ascribed to Tortonian or even to Middle Miocene. However they are Upper Messinian to Lower Zanclean. Esbarrondadoiro Formation is younger than Lower Member of Cacela Formation in Algarve and, with even stronger reason, than the upper-most well dated marine levels in Tagus basin. Age of Miocene units dealt with here has been based on small mammals found in marine sands.

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O artigo apresenta o processo de elaboração do questionário utilizado no Estudo Longitudinal de Saúde do Adulto (ELSA-Brasil). Iniciamos pelo relato sobre a "Seleção de Temas" abordados no questionário, cujo conteúdo teria que abranger o conhecimento disponível acerca da complexa rede de causalidade dos desfechos de interesse, assim como possibilitar a comparabilidade com estudos semelhantes. Contextualizamos a "tradução e a adaptação de instrumentos de medida", necessárias no caso de escalas de avaliação de vizinhanças, do instrumento para diagnóstico de transtornos depressivos e de ansiedade, e do questionário de frequência alimentar. A seguir, comentamos os critérios que nortearam a "ordem dos blocos temáticos" e finalmente a importância prática dos "pré-testes e estudos-piloto". As relações entre o conjunto de informações reunidas no ELSA poderão constituir contribuição original sobre os fatores que causam ou agravam os desfechos de interesse no contexto brasileiro, assim como sobre seus fatores de proteção.

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When the Internet was born, the purpose was to interconnect computers to share digital data at large-scale. On the other hand, when embedded systems were born, the objective was to control system components under real-time constraints through sensing devices, typically at small to medium scales. With the great evolution of the Information and Communication Technology (ICT), the tendency is to enable ubiquitous and pervasive computing to control everything (physical processes and physical objects) anytime and at a large-scale. This new vision gave recently rise to the paradigm of Cyber-Physical Systems (CPS). In this position paper, we provide a realistic vision to the concept of the Cyber-Physical Internet (CPI), discuss its design requirements and present the limitations of the current networking abstractions to fulfill these requirements. We also debate whether it is more productive to adopt a system integration approach or a radical design approach for building large-scale CPS. Finally, we present a sample of realtime challenges that must be considered in the design of the Cyber-Physical Internet.

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Simulators are indispensable tools to support the development and testing of cooperating objects such as wireless sensor networks (WSN). However, it is often not possible to compare the results of different simulation tools. Thus, the goal of this paper is the specification of a generic simulation platform for cooperating objects. We propose a platform that consists of a set of simulators that together fulfill desired simulator properties. We show that to achieve comparable results the use of a common specification language for the software-under-test is not feasible. Instead, we argue that using common input formats for the simulated environment and common output formats for the results is useful. This again motivates that a simulation tool consisting of a set of existing simulators that are able to use common scenario-input and can produce common output which will bring us a step closer to the vision of achieving comparable simulation results.

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Wireless sensor networks (WSNs) emerge as underlying infrastructures for new classes of large-scale networked embedded systems. However, WSNs system designers must fulfill the quality-of-service (QoS) requirements imposed by the applications (and users). Very harsh and dynamic physical environments and extremely limited energy/computing/memory/communication node resources are major obstacles for satisfying QoS metrics such as reliability, timeliness, and system lifetime. The limited communication range of WSN nodes, link asymmetry, and the characteristics of the physical environment lead to a major source of QoS degradation in WSNs-the ldquohidden node problem.rdquo In wireless contention-based medium access control (MAC) protocols, when two nodes that are not visible to each other transmit to a third node that is visible to the former, there will be a collision-called hidden-node or blind collision. This problem greatly impacts network throughput, energy-efficiency and message transfer delays, and the problem dramatically increases with the number of nodes. This paper proposes H-NAMe, a very simple yet extremely efficient hidden-node avoidance mechanism for WSNs. H-NAMe relies on a grouping strategy that splits each cluster of a WSN into disjoint groups of non-hidden nodes that scales to multiple clusters via a cluster grouping strategy that guarantees no interference between overlapping clusters. Importantly, H-NAMe is instantiated in IEEE 802.15.4/ZigBee, which currently are the most widespread communication technologies for WSNs, with only minor add-ons and ensuring backward compatibility with their protocols standards. H-NAMe was implemented and exhaustively tested using an experimental test-bed based on ldquooff-the-shelfrdquo technology, showing that it increases network throughput and transmission success probability up to twice the values obtained without H-NAMe. H-NAMe effectiveness was also demonstrated in a target tracking application with mobile robots - over a WSN deployment.