The solution of distributed mutual exclusion is difficult in Ad hoc networks owing to dynamic topologies and mobility. Based on the analysis of the properties of Ad hoc networks and the disadvantages of the traditiona...The solution of distributed mutual exclusion is difficult in Ad hoc networks owing to dynamic topologies and mobility. Based on the analysis of the properties of Ad hoc networks and the disadvantages of the traditional algorithms, an improved Ad hoc system model was given and a novel algorithm was presented as AHDME （Ad Hoc Distributed Mutual Exclusion）; it was based on the token-asking algorithms. It utilized broadcast to search for the token and to decrease the message complexity of multi-hop Ad hoc networks. Lamport＇s timestamp was improved to ensure the time sequence and to prevent nodes from starvation. When compared to traditional algorithms, AHDME does not require the fixed size of request queues and the global system information, which adapts itself to the frequent arrival/departures and the limited computing capability of nodes in Ad hoc networks. Performance analysis and simulation results show that the AHDME algorithm has low message complexity, small space complexity, and short response delay.展开更多
在综合研究知识网格的基础上,针对网格平台异构性、动态性和分布性等特点提出一种适应网格平台的多策略关联规则挖掘算法(multiple-strategies based hybrid distribution algorithm,MBHD).MBHD在HD算法的基础上,融合了市场机制优化策...在综合研究知识网格的基础上,针对网格平台异构性、动态性和分布性等特点提出一种适应网格平台的多策略关联规则挖掘算法(multiple-strategies based hybrid distribution algorithm,MBHD).MBHD在HD算法的基础上,融合了市场机制优化策略、时间戳机制和令牌环策略,有效克服了网格中制约算法性能的负载均衡问题,并避免了不必要的网络负载和网络竞争的产生,从而解决了关联规则挖掘中最关键的算法耗时问题,并提高了算法的效率和性能.实验给出了对应于不同处理器节点数量和最小支持度时的算法响应时间,表明本算法能够很好地适应网格平台特性,且其性能和可扩展性有明显提高.展开更多
基金the Application Fundamental Research Foundation of Sichuan Province, China(04JY029-017-2)the Innovation Fund for Small Technology-based Firms China(04JY029-017-2)
文摘The solution of distributed mutual exclusion is difficult in Ad hoc networks owing to dynamic topologies and mobility. Based on the analysis of the properties of Ad hoc networks and the disadvantages of the traditional algorithms, an improved Ad hoc system model was given and a novel algorithm was presented as AHDME （Ad Hoc Distributed Mutual Exclusion）; it was based on the token-asking algorithms. It utilized broadcast to search for the token and to decrease the message complexity of multi-hop Ad hoc networks. Lamport＇s timestamp was improved to ensure the time sequence and to prevent nodes from starvation. When compared to traditional algorithms, AHDME does not require the fixed size of request queues and the global system information, which adapts itself to the frequent arrival/departures and the limited computing capability of nodes in Ad hoc networks. Performance analysis and simulation results show that the AHDME algorithm has low message complexity, small space complexity, and short response delay.
文摘在综合研究知识网格的基础上,针对网格平台异构性、动态性和分布性等特点提出一种适应网格平台的多策略关联规则挖掘算法(multiple-strategies based hybrid distribution algorithm,MBHD).MBHD在HD算法的基础上,融合了市场机制优化策略、时间戳机制和令牌环策略,有效克服了网格中制约算法性能的负载均衡问题,并避免了不必要的网络负载和网络竞争的产生,从而解决了关联规则挖掘中最关键的算法耗时问题,并提高了算法的效率和性能.实验给出了对应于不同处理器节点数量和最小支持度时的算法响应时间,表明本算法能够很好地适应网格平台特性,且其性能和可扩展性有明显提高.
