基于QoS多目标优化的Web服务组合方法

为了确保在服务组合中获得Pareto最优解集,把服务组合建模为多个服务质量属性同时优化的多目标优化问题,提出了一种依据服务质量属性类型的通用预处理方法,采用多个信息素表和单个启发式信息表的多目标蚁群算法,蚂蚁随机选择一种信息素表建构可行解,每个蚁群周期完成后所有信息素都会蒸发,但每个优化函数只有一个最优解获得信息素增加,经过多过蚁群周期后即可解获得最优解集.实验结果表明,该方法可为Web服务组合提供一种很好的优化方案,具有很高的准确率.

Web services composition method based on QoS by multiple objective optimization

To obtain the Pareto optimal solution set of Web services composition,Web services composition is modeled to multi-objective optimization of multiple quality of service.A generic pretreated method based on service quality attributes type is proposed.Several pheromone tables and single heuristic information table are adopted in this multi-objective ant colony algorithm.The ant selected a pheromone table randomly and constructed a feasible solution.All pheromone evaporate partly after each ant colony cycle,but only the optimal solution’s members obtains pheromone increase for each optimization function.The optimal solution set could obtain after a lot of ant colony cycle.Simulation shows that the method provide a good optimized scheme for web services composition with high accuracy.