Abstract: To implement the combination of complex Web services according to user's request,and to guarantee the Quality of Service (QoS) for maximizing improve services efficiency,aiming at the problem of QoS-aware in Web service combination,the concept of chaos was introduced,and a new method of Web services combination based on Chaotic Genetic Algorithm (CGA) was proposed.The chaos theory was used to generate the initial population.The selection,crossover and mutation operation in genetic algorithm were used to realize the evolution of population.Small chaotic disturbances were added to the offspring population after each evolution,which effectively overcame the disadvantages of premature and slow convergence speed of genetic algorithm.The experiments showed that the proposed method could achieve faster convergence speed and higher reliability than the existing chaos genetic algorithm.

Key words: Web services, genetic algorithms, chaos, QoS-aware, global optimization

摘要： 为了根据用户的请求实现Web服务的自动组合,在保证服务质量的前提下最大化地提高服务效率,针对Web服务组合中的服务质量感知问题,引入混沌的概念,提出一种基于混沌遗传算法的Web服务组合方法。该方法利用混沌理论产生种群的初始群体,根据遗传算法的选择、交叉、变异操作实现种群进化,通过对每次进化后的子代群体附加混沌小扰动有效地克服了遗传算法早熟和收敛速度慢的缺点。实验表明,该方法可以获得比现有混沌遗传算法更快的收敛速度和更高的可靠性。

关键词: Web服务, 遗传算法, 混沌, QoS感知, 全局优化