Computational grid for highperformance computing is the current research focus of computerscience. Furthermore, the performance analysis and evaluation toward parallel programs is critical in grid computing environm...
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It is likely that an ensemble of overlapping heterogeneous wireless networks will be required to provide ubiquitous data communications. In this scenario, the mobile user's choice of network will directly affect t...
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It is likely that an ensemble of overlapping heterogeneous wireless networks will be required to provide ubiquitous data communications. In this scenario, the mobile user's choice of network will directly affect the applications' performance. This paper examines this decision, and proposes that it is made by the client application by considering network characteristics and cost. This is facilitated by a modified version of SCTP. Using simulation results, we show that a marked improvement in application performance is possible by monitoring the available networks, and making the appropriate selection.
Due to over-abundant information on the Web, information filtering becomes a key task for online users to obtain relevant suggestions and how to extract the most related item is always a key topic for researchers in v...
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Due to over-abundant information on the Web, information filtering becomes a key task for online users to obtain relevant suggestions and how to extract the most related item is always a key topic for researchers in various fields. In this paper, we adopt tools used to analyze complex networks to evaluate user reputation and item quality. In our proposed Accumulative Time Based Ranking (ATR) algorithm, we take into account the growth record of the network to identify the evolution of the reputation of users and the quality of items, by incorporating two behavior weighting factors which can capture the hidden facts on reputation and quality dynamics for each user and item respectively. Our proposed ATR algorithm mainly combines the iterative approach to rank user reputation and item quality with temporal dependence compared with other reputation evaluation methods. We show that our algorithm outperforms other benchmark ranking algorithms in terms of precision and robustness on empirical datasets from various online retailers and the citation datasets among research publications. Therefore, our proposed method has the capability to effectively evaluate user reputation and item quality.
This paper reports on our experience in writing a parallel version of a chaos router simulator using the new data-driven parallel language ZPL. The simulator is a large program that tests the capabilities of ZPL. The ...
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ISBN:
(纸本)0780333837
This paper reports on our experience in writing a parallel version of a chaos router simulator using the new data-driven parallel language ZPL. The simulator is a large program that tests the capabilities of ZPL. The (parallel) ZPL program is compared with the existing serial implementation on two very different architectures: a 16-processor Intel Paragon and a cluster of eight Alpha workstations. On the Paragon, the simulator performs best when simulating medium- to large-sized routers, and on the Alpha cluster, it performs best when simulating large routers. Thus a user can choose the parallel platform best suited to the router size.
Wireless sensor networks have posed a number of challenging problems such as localization, deployment and tracking, etc. One of the interesting problems is the calculation of the coverage and exposure paths for the se...
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Wireless sensor networks have posed a number of challenging problems such as localization, deployment and tracking, etc. One of the interesting problems is the calculation of the coverage and exposure paths for the sensor networks. This paper presents a fully localized algorithm to solve the worst coverage problem first introduced by Meguerdichian et al. The nodes of the sensor network cooperate to construct the worst coverage path only by the one-hop neighbor＇s information, thus avoiding the massive communication and conserving the energy. The correctness of the proposed algorithm is proved formally under the sensing diminishing model. Moreover, this algorithm can be easily extended to solve the minimal exposure problem with local information as well.
Multiple physical layer rates are supported in IEEE 802.11-based wireless networks, where links can adopt joint transmission power control and rate adaptation to achieve energy efficiency. This paper studies the selfi...
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In this paper, a unified model for time-dependent Maxwell equations in dispersive media is considered. The space-time DG method developed in [29] is applied to solve the un-derlying problem. Unconditional L2-stability...
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In this paper, a unified model for time-dependent Maxwell equations in dispersive media is considered. The space-time DG method developed in [29] is applied to solve the un-derlying problem. Unconditional L2-stability and error estimate of order O？τr＋1＋hk＋1/2？ are obtained when polynomials of degree at most r and k are used for the temporal dis-cretization and spatial discretization respectively. 2-D and 3-D numerical examples are given to validate the theoretical results. Moreover, numerical results show an ultra-convergence of order 2r＋1 in temporal variable t.
The issue of data privacy is considered a significant hindrance to the development and industrial applications of database publishing and data mining techniques. Among many privacy-preserving methodologies, data pertu...
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ISBN:
(纸本)9781615671090
The issue of data privacy is considered a significant hindrance to the development and industrial applications of database publishing and data mining techniques. Among many privacy-preserving methodologies, data perturbation is a popular technique for achieving a balance between data utility and information privacy. It is known that the attacker's background information about the original data can play a significant role in breaching data privacy. In this paper, we analyze data perturbation's potential privacy vulnerability in the presence of known background information in privacy-preserving database publishing and data mining based on the eigenspace of the perturbed data under some constraints. We study the situation in which data privacy may be compromised with the leakage of a few original data records. We first show that additive perturbation preserves the angle between data records during the perturbation. Based on this angle-preservation property, we show that, in a general perturbation model, even the leakage of only one single original data probably degrades the privacy of perturbed data in some cases. We theoretically and experimentally show that a general data perturbation model is vulnerable from this type of background privacy breach.
We investigate the use of the multistep successive preconditioning strategies (MSP) to construct a class of parallel multilevel sparse approximate inverse (SAI) preconditioners. We do not use independent set ordering,...
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Quantum walk, the quantum counterpart of random walk, is an important model and widely studied to develop new quantum algorithms. This paper studies the relationship between the continuous-time quantum walk and the sy...
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Quantum walk, the quantum counterpart of random walk, is an important model and widely studied to develop new quantum algorithms. This paper studies the relationship between the continuous-time quantum walk and the symmetry of a graph, especially that of a tree. Firstly, we prove in mathematics that the symmetry of a graph is highly related to quantum walk. Secondly, we propose an algorithm based on the continuous-time quantum walk to compute the symmetry of a tree. Our algorithm has better time complexity O（N3） than the current best algorithm. Finally, through testing three types of 10024 trees, we find that the symmetry of a tree can be found with an extremely high efficiency with the help of the continuous-time quantum walk.
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