857 resultados para Internet (Computer networks)
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Item 247.
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Includes bibliographical references.
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Mode of access: Internet.
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Includes bibliographical references (p. 27).
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Seventy-two clinically anxious children, aged 7 to 14 years, were randomly allocated to clinic-based, cognitive-behavior therapy, the same treatment partially delivered Via the Internet. or a wait-list control (WL). Children in the clinic and clinic-plus-Internet conditions showed significantly greater reductions in anxiety from pre- to posttreatment and were more likely to be free of their anxiety diagnoses, compared with the WL group. Improvements were maintained at 12-month follow-up for both therapy conditions', with minimal difference in outcomes between interventions. The Internet treatment content was highly acceptable to families, with minimal dropout and a high level of therapy compliance.
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Aliadas aos estudos sobre sustentabilidade, há inúmeras discussões e atitudes para combater consequências do uso irracional dos recursos naturais do planeta. Surge assim o entendimento do consumo, suas influências e alternativas. O indivíduo pode ter hábitos de consumo de forma consumista ou de forma consciente. O consumista é entendido como o oposto dos hábitos do consumidor consciente, sendo levado pelo impulso e pelo estímulo à compra, sem avaliar suas necessidades e impactos futuros. O consumo é de fato indispensável à humanidade. Entretanto, quando aplicado de forma exacerbada e incorreta, pode gerar sérias consequências sociais e/ou ambientais. O consumidor consciente tem a qualificação de avaliar dentre as possibilidades existentes, os impactos que podem ser ocasionados com a aquisição, de tal modo, a minimizar suas consequências e contribuir de alguma forma para uma sociedade mais sustentável. O principal objetivo desta pesquisa foi compreender a aderência dos pesquisados ao comportamento de consumo consciente, bem como avaliar o compartilhamento de informações sobre o tema por pessoas que estão inseridas em alguma rede social na internet, partindo do pressuposto que este é um dos principais meios de comunicação e compartilhamento de informações. Para a pesquisa, foi utilizada a metodologia de análise qualitativa de caráter exploratório e a técnica de entrevistas em profundidade baseada em roteiro semiestruturado. Por meio da análise do conteúdo, a compreensão dos resultados aponta que todos os entrevistados possuem um grau de conhecimento sobre o consumo consciente e a maioria tenta ter algum tipo de ação consciente. Mas, ao mesmo tempo, esses indivíduos podem sofrer influências neste processo principalmente de caráter pessoal, levando à alteração de ação. Com relação ao compartilhamento do tema nas redes sociais na internet, foi possível identificar que grande parte dos entrevistados já teve algum tipo de experiência da situação, mas ainda em pequena escala, com poucas ocorrências. Também acredita-se que o canal pode ser utilizado para a proliferação do tema, o que nos leva à conclusão de que é um canal viável ao compartilhamento. Porém, mediante a ruptura de hábitos, é utilizado para a ocorrência de um maior engajamento por parte dos usuários. A análise apresenta uma compreensão e perspectivas a partir do recorte estudado, abrindo horizonte para novos estudos e aprofundamento das reflexões apresentadas neste trabalho.
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Congestion control is critical for the provisioning of quality of services (QoS) over dedicated short range communications (DSRC) vehicle networks for road safety applications. In this paper we propose a congestion control method for DSRC vehicle networks at road intersection, with the aims of providing high availability and low latency channels for high priority emergency safety applications while maximizing channel utilization for low priority routine safety applications. In this method a offline simulation based approach is used to find out the best possible configurations of message rate and MAC layer backoff exponent (BE) for a given number of vehicles equipped with DSRC radios. The identified best configurations are then used online by an roadside access point (AP) for system operation. Simulation results demonstrated that this adaptive method significantly outperforms the fixed control method under varying number of vehicles. The impact of estimation error on the number of vehicles in the network on system level performance is also investigated.
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The paper describes education complex "Multi-agent Technologies for Parallel and Distributed Information Processing in Telecommunication Networks".
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Computer networks produce tremendous amounts of event-based data that can be collected and managed to support an increasing number of new classes of pervasive applications. Examples of such applications are network monitoring and crisis management. Although the problem of distributed event-based management has been addressed in the non-pervasive settings such as the Internet, the domain of pervasive networks has its own characteristics that make these results non-applicable. Many of these applications are based on time-series data that possess the form of time-ordered series of events. Such applications also embody the need to handle large volumes of unexpected events, often modified on-the-fly, containing conflicting information, and dealing with rapidly changing contexts while producing results with low-latency. Correlating events across contextual dimensions holds the key to expanding the capabilities and improving the performance of these applications. This dissertation addresses this critical challenge. It establishes an effective scheme for complex-event semantic correlation. The scheme examines epistemic uncertainty in computer networks by fusing event synchronization concepts with belief theory. Because of the distributed nature of the event detection, time-delays are considered. Events are no longer instantaneous, but duration is associated with them. Existing algorithms for synchronizing time are split into two classes, one of which is asserted to provide a faster means for converging time and hence better suited for pervasive network management. Besides the temporal dimension, the scheme considers imprecision and uncertainty when an event is detected. A belief value is therefore associated with the semantics and the detection of composite events. This belief value is generated by a consensus among participating entities in a computer network. The scheme taps into in-network processing capabilities of pervasive computer networks and can withstand missing or conflicting information gathered from multiple participating entities. Thus, this dissertation advances knowledge in the field of network management by facilitating the full utilization of characteristics offered by pervasive, distributed and wireless technologies in contemporary and future computer networks.
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Network simulation is an indispensable tool for studying Internet-scale networks due to the heterogeneous structure, immense size and changing properties. It is crucial for network simulators to generate representative traffic, which is necessary for effectively evaluating next-generation network protocols and applications. With network simulation, we can make a distinction between foreground traffic, which is generated by the target applications the researchers intend to study and therefore must be simulated with high fidelity, and background traffic, which represents the network traffic that is generated by other applications and does not require significant accuracy. The background traffic has a significant impact on the foreground traffic, since it competes with the foreground traffic for network resources and therefore can drastically affect the behavior of the applications that produce the foreground traffic. This dissertation aims to provide a solution to meaningfully generate background traffic in three aspects. First is realism. Realistic traffic characterization plays an important role in determining the correct outcome of the simulation studies. This work starts from enhancing an existing fluid background traffic model by removing its two unrealistic assumptions. The improved model can correctly reflect the network conditions in the reverse direction of the data traffic and can reproduce the traffic burstiness observed from measurements. Second is scalability. The trade-off between accuracy and scalability is a constant theme in background traffic modeling. This work presents a fast rate-based TCP (RTCP) traffic model, which originally used analytical models to represent TCP congestion control behavior. This model outperforms other existing traffic models in that it can correctly capture the overall TCP behavior and achieve a speedup of more than two orders of magnitude over the corresponding packet-oriented simulation. Third is network-wide traffic generation. Regardless of how detailed or scalable the models are, they mainly focus on how to generate traffic on one single link, which cannot be extended easily to studies of more complicated network scenarios. This work presents a cluster-based spatio-temporal background traffic generation model that considers spatial and temporal traffic characteristics as well as their correlations. The resulting model can be used effectively for the evaluation work in network studies.
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Postprint
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Network simulation is an indispensable tool for studying Internet-scale networks due to the heterogeneous structure, immense size and changing properties. It is crucial for network simulators to generate representative traffic, which is necessary for effectively evaluating next-generation network protocols and applications. With network simulation, we can make a distinction between foreground traffic, which is generated by the target applications the researchers intend to study and therefore must be simulated with high fidelity, and background traffic, which represents the network traffic that is generated by other applications and does not require significant accuracy. The background traffic has a significant impact on the foreground traffic, since it competes with the foreground traffic for network resources and therefore can drastically affect the behavior of the applications that produce the foreground traffic. This dissertation aims to provide a solution to meaningfully generate background traffic in three aspects. First is realism. Realistic traffic characterization plays an important role in determining the correct outcome of the simulation studies. This work starts from enhancing an existing fluid background traffic model by removing its two unrealistic assumptions. The improved model can correctly reflect the network conditions in the reverse direction of the data traffic and can reproduce the traffic burstiness observed from measurements. Second is scalability. The trade-off between accuracy and scalability is a constant theme in background traffic modeling. This work presents a fast rate-based TCP (RTCP) traffic model, which originally used analytical models to represent TCP congestion control behavior. This model outperforms other existing traffic models in that it can correctly capture the overall TCP behavior and achieve a speedup of more than two orders of magnitude over the corresponding packet-oriented simulation. Third is network-wide traffic generation. Regardless of how detailed or scalable the models are, they mainly focus on how to generate traffic on one single link, which cannot be extended easily to studies of more complicated network scenarios. This work presents a cluster-based spatio-temporal background traffic generation model that considers spatial and temporal traffic characteristics as well as their correlations. The resulting model can be used effectively for the evaluation work in network studies.
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Computer networks produce tremendous amounts of event-based data that can be collected and managed to support an increasing number of new classes of pervasive applications. Examples of such applications are network monitoring and crisis management. Although the problem of distributed event-based management has been addressed in the non-pervasive settings such as the Internet, the domain of pervasive networks has its own characteristics that make these results non-applicable. Many of these applications are based on time-series data that possess the form of time-ordered series of events. Such applications also embody the need to handle large volumes of unexpected events, often modified on-the-fly, containing conflicting information, and dealing with rapidly changing contexts while producing results with low-latency. Correlating events across contextual dimensions holds the key to expanding the capabilities and improving the performance of these applications. This dissertation addresses this critical challenge. It establishes an effective scheme for complex-event semantic correlation. The scheme examines epistemic uncertainty in computer networks by fusing event synchronization concepts with belief theory. Because of the distributed nature of the event detection, time-delays are considered. Events are no longer instantaneous, but duration is associated with them. Existing algorithms for synchronizing time are split into two classes, one of which is asserted to provide a faster means for converging time and hence better suited for pervasive network management. Besides the temporal dimension, the scheme considers imprecision and uncertainty when an event is detected. A belief value is therefore associated with the semantics and the detection of composite events. This belief value is generated by a consensus among participating entities in a computer network. The scheme taps into in-network processing capabilities of pervasive computer networks and can withstand missing or conflicting information gathered from multiple participating entities. Thus, this dissertation advances knowledge in the field of network management by facilitating the full utilization of characteristics offered by pervasive, distributed and wireless technologies in contemporary and future computer networks.
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Este estudio busca profundizar en los motivadores e inhibidores hacia el uso de una herramienta digital dirigida a jugadores de fútbol no profesional, que permita formar una comunidad para la convocatoria de partidos de dicho deporte, reserva de canchas en línea y reconocimiento del talento de los jugadores -- Se identifica la aceptación de dicha herramienta digital por parte tanto de los jugadores no profesionales como de los negocios de alquiler de canchas sintéticas -- Se aborda el estado del uso de internet y de teléfonos inteligentes en el área metropolitana de Medellín, Colombia, como factores claves de éxito que facilitan la adopción de la herramienta digital evaluada -- Se acudió a la investigación cualitativa de fuentes primarias con entrevistas en profundidad y encuestas, así como a la indagación en fuentes secundarias de la literatura relacionada con la situación en estudio -- El proyecto tuvo la finalidad de determinar si la herramienta digital sería aceptada o no y cuáles serían los contenidos e interacciones deseados por los posibles usuarios