Web quality of service (QoS) awareness requires not only the selection of specific services to complete specific tasks, but also the comprehensive quality of service of the whole web service composition. How to select...Web quality of service (QoS) awareness requires not only the selection of specific services to complete specific tasks, but also the comprehensive quality of service of the whole web service composition. How to select the web service composition with the highest comprehensive QoS is a NP hard problem. In this paper, an improved multi population genetic algorithm is proposed. Cosine adaptive operator is added to the algorithm to avoid premature algorithm caused by improper genetic operator and the disadvantage of destroying excellent individuals in later period. Experimental results show that compared with the common genetic algorithm and multi population genetic algorithm, this algorithm has the advantages of shorter time consumption and higher accuracy, and effectively avoids the loss of effective genes in the population.展开更多
To improve the Quality of Service (QoS)-aware Web service compositions considering constraints between cross-organizational business,this paper analyzes the types of constraints,and accordingly proposes a Chaos Geneti...To improve the Quality of Service (QoS)-aware Web service compositions considering constraints between cross-organizational business,this paper analyzes the types of constraints,and accordingly proposes a Chaos Genetic Algorithm (CGA). The algorithm creates an initial population of service compositions based on the chaos theory,and then processes individuals which violate constraints in the initial population using repair strategies. Next,a new fitness function is designed to gradually eliminate the infeasible compositions generated in evolution. Finally,the algorithm makes minor chaotic disturbances on the evolved group to accelerate convergence and avoid local optimum. Experimental results demonstrate the effectiveness of the proposed algorithm.展开更多
把多个简单Web服务组合成为更强大的组合Web服务是面向服务计算的目标之一。由于存在多个功能相同但服务质量属性不同的候选Web服务,因此需要针对服务质量要求进行服务组合。鉴于Web服务组合规模的不断增长和特定领域的时限要求,面向实...把多个简单Web服务组合成为更强大的组合Web服务是面向服务计算的目标之一。由于存在多个功能相同但服务质量属性不同的候选Web服务,因此需要针对服务质量要求进行服务组合。鉴于Web服务组合规模的不断增长和特定领域的时限要求,面向实时大规模Web服务组合问题的快速收敛算法尤为重要,然而目前相关工作还很少。论文提出一种新的Web服务组合算法GAELS(Genetic Algorithm Embedded Local Searching),运用高适应度初始种群和局部搜索的变异策略,加快收敛速度。通过实验评测表明与简单遗传算法相比,GAELS算法能更快得到近似最优解,且随着服务规模增长,拥有更好的适应性。展开更多
如何选择最佳服务是Web服务组合研究领域的重要问题之一。目前工业界和学术界在绑定目标服务时非常关注组合服务的功能匹配,而忽略了非功能属性对组合效果的影响。采用遗传算法优化Web服务QoS(Quality of Service),提出在组合服务实时...如何选择最佳服务是Web服务组合研究领域的重要问题之一。目前工业界和学术界在绑定目标服务时非常关注组合服务的功能匹配,而忽略了非功能属性对组合效果的影响。采用遗传算法优化Web服务QoS(Quality of Service),提出在组合服务实时运行过程中基于QoS进行动态绑定和再绑定的方法,并给出了具体的实施方案。实验显示它可以大大提高Web服务动态组合的运行效率。展开更多
Web服务作为一种新型的Web应用模式,近年来得到了迅速的发展.如何动态地把现存的各种Web服务整合起来以形成新的、满足不同用户需求的、增值的复杂服务已成为新的应用需求和研究热点.针对现有服务聚合中服务选择技术的不足,提出了一种...Web服务作为一种新型的Web应用模式,近年来得到了迅速的发展.如何动态地把现存的各种Web服务整合起来以形成新的、满足不同用户需求的、增值的复杂服务已成为新的应用需求和研究热点.针对现有服务聚合中服务选择技术的不足,提出了一种解决服务聚合中服务动态选择QoS全局最优化问题的实现算法GODSS(global optimal of dynamic Web services selection).算法的主要思想是把服务动态选择全局最优化问题转化为一个带QoS约束的多目标服务组合优化问题,利用多目标遗传算法的智能优化原理,通过同时优化多个目标函数,最终产生一组满足约束条件的Pareto优化服务聚合流程集.理论分析和实验结果说明了算法的可行性和有效性.展开更多
文摘Web quality of service (QoS) awareness requires not only the selection of specific services to complete specific tasks, but also the comprehensive quality of service of the whole web service composition. How to select the web service composition with the highest comprehensive QoS is a NP hard problem. In this paper, an improved multi population genetic algorithm is proposed. Cosine adaptive operator is added to the algorithm to avoid premature algorithm caused by improper genetic operator and the disadvantage of destroying excellent individuals in later period. Experimental results show that compared with the common genetic algorithm and multi population genetic algorithm, this algorithm has the advantages of shorter time consumption and higher accuracy, and effectively avoids the loss of effective genes in the population.
基金National Natural Science Fund of China(61672022,61272036)Graduate Innovation Program of Shanghai Polytechnic University(A01GY17F022)Key Discipline of Shanghai Polytechnic University(XXKZD1604)
文摘To improve the Quality of Service (QoS)-aware Web service compositions considering constraints between cross-organizational business,this paper analyzes the types of constraints,and accordingly proposes a Chaos Genetic Algorithm (CGA). The algorithm creates an initial population of service compositions based on the chaos theory,and then processes individuals which violate constraints in the initial population using repair strategies. Next,a new fitness function is designed to gradually eliminate the infeasible compositions generated in evolution. Finally,the algorithm makes minor chaotic disturbances on the evolved group to accelerate convergence and avoid local optimum. Experimental results demonstrate the effectiveness of the proposed algorithm.
文摘把多个简单Web服务组合成为更强大的组合Web服务是面向服务计算的目标之一。由于存在多个功能相同但服务质量属性不同的候选Web服务,因此需要针对服务质量要求进行服务组合。鉴于Web服务组合规模的不断增长和特定领域的时限要求,面向实时大规模Web服务组合问题的快速收敛算法尤为重要,然而目前相关工作还很少。论文提出一种新的Web服务组合算法GAELS(Genetic Algorithm Embedded Local Searching),运用高适应度初始种群和局部搜索的变异策略,加快收敛速度。通过实验评测表明与简单遗传算法相比,GAELS算法能更快得到近似最优解,且随着服务规模增长,拥有更好的适应性。
文摘如何选择最佳服务是Web服务组合研究领域的重要问题之一。目前工业界和学术界在绑定目标服务时非常关注组合服务的功能匹配,而忽略了非功能属性对组合效果的影响。采用遗传算法优化Web服务QoS(Quality of Service),提出在组合服务实时运行过程中基于QoS进行动态绑定和再绑定的方法,并给出了具体的实施方案。实验显示它可以大大提高Web服务动态组合的运行效率。
基金Supported by the National HighTech Research and Development Plan of China under Grant Nos.2002AA1340102002AA1340202003AA135110(国家高技术研究发展计划(863))
文摘Web服务作为一种新型的Web应用模式,近年来得到了迅速的发展.如何动态地把现存的各种Web服务整合起来以形成新的、满足不同用户需求的、增值的复杂服务已成为新的应用需求和研究热点.针对现有服务聚合中服务选择技术的不足,提出了一种解决服务聚合中服务动态选择QoS全局最优化问题的实现算法GODSS(global optimal of dynamic Web services selection).算法的主要思想是把服务动态选择全局最优化问题转化为一个带QoS约束的多目标服务组合优化问题,利用多目标遗传算法的智能优化原理,通过同时优化多个目标函数,最终产生一组满足约束条件的Pareto优化服务聚合流程集.理论分析和实验结果说明了算法的可行性和有效性.
