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排序方式: 共有10000条查询结果,搜索用时 15 毫秒
991.
Huanyu Zhao 《计算机科学技术学报》2009,24(5):833-843
Peer-to-Peer Desktop Grid (P2PDG) has emerged as a pervasive cyber-infrastructure tackling many large-scale applications with
high impacts. As a burgeoning research area, P2PDG can support numerous applications, including scientific computing, file
sharing, web services, and virtual organization for collaborative activities and projects. To handle trustworthiness issues
of these services, trust and reputation schemes are proposed to establish trust among peers in P2PDG. In this paper, we propose
a robust group trust management system, called H-Trust, inspired by the H-index aggregation technique. Leveraging the robustness
of the H-index algorithm under incomplete and uncertain circumstances, H-Trust offers a robust personalized reputation evaluation
mechanism for both individual and group trusts with minimal communication and computation overheads. We present the H-Trust
scheme in five phases, including trust recording, local trust evaluation, trust query phase, spatial-temporal update phase,
and group reputation evaluation phases. The rationale for its design, the analysis of the algorithm are further investigated.
To validate the performance of H-Trust scheme, we designed the H-Trust simulator HTrust-Sim to conduct multi-agent-based simulations.
Simulation results demonstrate that H-Trust is robust and can identify and isolate malicious peers in large scale systems
even when a large portion of peers are malicious. 相似文献
992.
993.
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995.
Petroplan软件应用最优化方法实现炼油企业的利润最优化,本文利用Petroplan软件建立了炼油企业的全流程模型,并进行了多项优化应用研究,包括原油选购、流程模拟与优化、投资分析及经济效益测算、企业生产瓶颈分析、物流走向优化等.还建立了相应的PIMS对比模型分别进行对比,二者的结果比较接近,最大误差只有1.1%,表明由Petrolplan建立的炼油厂模型也可以为炼油企业的生产经营提供指导方案. 相似文献
996.
997.
基于误差预测的焦炉火道温度软测量模型 总被引:2,自引:0,他引:2
针对焦炉火道温度在线检测的问题,在分析焦炉火道温度特性的基础上,建立了一种基于误差预测的高精度焦炉火道温度软测量模型.首先分别建立了1元、2元和12元线性回归模型,对蓄顶温度和火道温度进行线性拟合;然后比较分析了三种回归子模型的特点.使用融合时间差分法的Elman神经网络,对线性回归模型中精度最高的12元模型的预测误差进行拟合和多步预测.采用专家经验将线性回归组合模型和融合时间差分法的Elman神经网络模型进行集成,最终获得了具有较高预测精度的焦炉火道温度软测量值.实际运行结果验证了该软测量模型的有效性. 相似文献
998.
本文阐述了PowerBuiler的WEB应用原理.并结合实例论述了利用PowerBuiler开发WEB应用的过程。 相似文献
999.
Reliable and Energy-Efficient Routing for Static Wireless Ad Hoc Networks with Unreliable Links 总被引:1,自引:0,他引:1
Li Xiang-Yang Wang Yu Chen Haiming Chu Xiaowen Wu Yanwei Qi Yong 《Parallel and Distributed Systems, IEEE Transactions on》2009,20(10):1408-1421
Energy efficient routing and power control techniques in wireless ad hoc networks have drawn considerable research interests recently. In this paper, we address the problem of energy efficient reliable routing for wireless ad hoc networks in the presence of unreliable communication links or devices or lossy wireless link layers by integrating the power control techniques into the energy efficient routing. We consider both the case when the link layer implements a perfect reliability and the case when the reliability is implemented through the transport layer, e.g., TCP. We study the energy efficient unicast and multicast when the links are unreliable. Subsequently, we study how to perform power control (thus, controlling the reliability of each communication link) such that the unicast routings use the least power when the communication links are unreliable, while the power used by multicast is close to optimum. Extensive simulations have been conducted to study the power consumption, the end-to-end delay, and the network throughput of our proposed protocols compared with existing protocols. 相似文献
1000.
Hua-Fu Li 《Multimedia Tools and Applications》2009,41(2):287-304
Mining of music data is one of the most important problems in multimedia data mining. In this paper, two research issues of
mining music data, i.e., online mining of music query streams and change detection of music query streams, are discussed.
First, we proposed an efficient online algorithm, FTP-stream (Frequent Temporal Pattern mining of streams), to mine all frequent melody structures over sliding windows of music melody sequence streams. An effective bit-sequence
representation is used in the proposed algorithm to reduce the time and memory needed to slide the windows. An effective list
structure is developed in the FTP-stream algorithm to overcome the performance bottleneck of 2-candidate generation. Experiments
show that the proposed algorithm FTP-stream only needs a half of memory requirement of original melody sequence data, and
just scans the music query stream once. After mining frequent melody structures, we developed a simple online algorithm, MQS-change
(changes of Music Query Streams), to detect the changes of frequent melody structures in current user-centered music query streams. Two music melody
structures (set of chord-sets and string of chord-sets) are maintained and four melody structure changes (positive burst,
negative burst, increasing change and decreasing change) are monitored in a new summary data structure, MSC-list (a list of Music Structure Changes). Experiments show that the MQS-change algorithm is an effective online method to detect the changes of music melody
structures over continuous music query streams.
相似文献
Hua-Fu LiEmail: |