93 resultados para Network Management


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To build the service-oriented applications in a wireless sensor network (WSN), the workflow can be utilized to compose a set of atomic services and execute the corresponding pre-designed processes. In general, WSN applications rely closely on the sensor data which are usually inaccurate or even incomplete in the resource-constrained WSN. Then, the erroneous sensor data will affect the execution of atomic services and furthermore the workflows, which form an important part in the bottom-to-up dynamics of WSN applications. In order to alleviate this issue, it is necessary to manage the workflow hierarchically. However, the hierarchical workflow management remains an open and challenging problem. In this paper, by adopting the Bloom filter as an effective connection between the sensor node layer and the upper application layer, a hierarchical workflow management approach is proposed to ensure the QoS of workflow-based WSN application . The case study and experimental evaluations demonstrate the capability of the proposed approach.

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A common occurrence in almost all full-scale natural disasters is the rapid destruction of the telecommunication infrastructure as the inevitable unfolds, which tends to halt the necessary communications between the humanitarian operators and the people in need. In such scenarios, the deployment of wireless networks would provide fast and temporary remedies, however these networks normally do not provide services to the end-users and ordinary people, instead they provide connectivity between groups of end-users administered by a local service provider. From a range of services provided to the end-users by the humanitarian operators, healthcare is by far the top priority. This is considered through the utilization of smartphones in a Mobile Health (mHealth) perspective, which is an emerging concept for monitoring and tracking end-user health conditions. This article considers an mHealth system used in a tsunami-stricken disaster scenario, including a discussion on the most recent advances of Device to Device (D2D) and LTE-Direct technologies.

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Research in common property, participatory resource management, and community development points to the central importance of organizational arrangements in conservation and development interventions. The dilemma facing contemporary conservation practitioners is how best to assist and facilitate such arrangements in support of participatory resource management and sustainable livelihoods, given the range of organizations, societal processes, and structures in which interventions might engage. This article presents some key findings from a study of stakeholder groups at 4 project sites, with information from a further 16 sites, in the Biodiversity Conservation Network: (1) Longstanding organizations had an established community niche, but could become bogged down in bureaucratic procedures; (2) poor communication between organizations was common and could undermine resource management; and (3) charismatic individuals and local elite interests could dominate groups, diminishing their representativeness. Based on these findings, the article argues that conservation professionals need to build their capacity as facilitators and negotiators, paying greater attention to how stakeholder groups form and function, their links to wider arenas, and the aims and positions of groups and individuals.

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Provisioning of real-time multimedia sessions over wireless cellular network poses unique challenges due to frequent handoff and rerouting of a connection. For this reason, the wireless networks with cellular architecture require efficient user mobility estimation and prediction. This paper proposes using Robust Extended Kalman Filter as a location heading altitude estimator of mobile user for next cell prediction in order to improve the connection reliability and bandwidth efficiency of the underlying system. Through analysis we demonstrate that our algorithm reduces the system complexity (compared to existing approach using pattern matching and Kalman filter) as it requires only two base station measurements or only the measurement from the closest base station. Further, the technique is robust against system uncertainties due to inherent deterministic nature in the mobility model. Through simulation, we show the accuracy and simplicity in implementation of our prediction algorithm.

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The availability of critical services and their data can be significantly increased by replicating them on multiple systems connected with each other, even in the face of system and network failures. In some platforms such as peer-to-peer (P2P) systems, their inherent characteristic mandates the employment of some form of replication to provide acceptable service to their users. However, the problem of how best to replicate data to build highly available peer-to-peer systems is still an open problem. In this paper, we propose an approach to address the data replication problem on P2P systems. The proposed scheme is compared with other techniques and is shown to require less communication cost for an operation as well as provide higher degree of data availability.

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Background: Heart Failure Management Programs (HFMPs) have proven to be cost-effective in minimising recurrent hospitalisations, morbidity and mortality. However, variability between the programs exists which could translate into variable health outcomes.
Objective: To survey the characteristics of HFMPs throughout Australia and to identify potential heterogeneity in their organisation and structure.
Method: Thirty-nine post-discharge HFMPs were identified from a systematic search of the Australian health-care system in 2002. A comprehensive 19-item questionnaire specifically examining characteristics of HFMPs was sent to co-ordinators of identified programs in early 2003.
Results: All participants responded with six institutions (15%) indicating that their HFMP had ceased operations due to a lack of funding. The survey revealed an uneven distribution of the 33 active HFMPs operating throughout Australia. Overall, 4450 post-discharge HF patients (median: 74; IQR: 24–147) were managed via these programs, representing only 11% of the potential caseload for an Australia-wide network of HFMPs. Heterogeneity of these programs existed in respect to the model of care applied within the program (70% applied a home-based program and 18% a specialist HF clinic) and applied interventions (30% of programs had no discharge criteria and 45% of programs prevented nurses administering/titrating medications). Sustained funding was available to only 52% of the active HFMPs.
Conclusion: Inequity of access to HFMPs in Australia is evident in relation to locality and high service demand, further complicated by inadequate funding. Heterogeneity between these programs is substantial. The development of national benchmarks for evidence-based HFMPs is required to address program variability and funding issues to realise their potential to improve health outcomes.


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This paper provides location estimation based power control strategy for cellular radio systems via a location based interference management scheme. Our approach considers the carrier-to-interference as dependent on the transmitter and receiver separation distance and therefore an accurate estimation of the precise locations can provide the power critical mobile user to control the transition power accordingly. In this fully
distributed algorithms, we propose using a Robust Extended Kalman Filter (REKF) to derive an estimate of the mobile user’s closest mobile base station from the user’s location, heading and altitude. Our analysis demonstrates that this algorithm can successfully track the mobile users with less system complexity, as it requires measurements from only one or two closest mobile base stations and hence enable the user to transmit at the rate that is sufficient for the interference management. Our power control
algorithms based on this estimation converges to the desired power trajectory. Further, the technique is robust against system uncertainties caused by the inherent deterministic nature of the mobility model. Through simulation, we show the accuracy of our prediction algorithm and the simplicity of its implementation.

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There exist multiple objectives in engineering management such as minimum cost and maximum service capacity. Although solution methods of multiobjective optimization problems have undergone continual development over the past several decades, the methods available to date are not particularly robust, and none of them performs well on the broad classes. Because genetic algorithms work with a population of points, they can capture a number of solutions simultaneously, and easily incorporate the concept of Pareto optimal set in their optimization process. In this paper, a genetic algorithm is modified to deal with the rehabilitation planning of bridge decks at a network level by minimizing the rehabilitation cost and deterioration degree simultaneously.

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Generally multiple objectives exist in transportation infrastructure management, such as minimum cost and maximum service capacity. Although solution methoak of multiobjective optimization problems have undergone continual development over the part several decades, the methods available to date are not particularly robust, and none of them perform well on the broad classes. Because genetic algorithms work with apopulation ofpoints, they can capture a number of solutions simultaneously, and easily incorporate the concept of a Pareto optimal set in their optimization process. In this paper, a genetic algorithm is modified to deal with an empirical application for the rehabilitation planning of bridge decks, at a network level, by minimizing the rehabilitation cost and deterioration degree simultaneously.

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The peer-to-peer content distribution network (PCDN) is a hot topic recently, and it has a huge potential for massive data intensive applications on the Internet. One of the challenges in PCDN is routing for data sources and data deliveries. In this paper, we studied a type of network model which is formed by dynamic autonomy area, structured source servers and proxy servers. Based on this network model, we proposed a number of algorithms to address the routing and data delivery issues. According to the highly dynamics of the autonomy area, we established dynamic tree structure proliferation system routing, proxy routing and resource searching algorithms. The simulations results showed that the performance of the proposed network model and the algorithms are stable.