一种基于QoS全局最优的服务选择算法

Web services selection algorithm with QoS global optimal

现有的服务选择算法存在低效、非全局最优等缺点。针对现有算法的不足,提出了一种基于QoS的高效服务选择算法。首先建立服务选择问题的多目标优化模型,之后用改进的多目标粒子群算法(IDMPSO)求解该模型,从而获得一组高质量最优解。在IDMPSO中,通过计算粒子的密集距离来进行Pareto最优解的保留,并把密集距离与欧几里德距离结合起来提出一种全局最优粒子选取的方法。实验结果表明,IDMPSO得到的解相对较优,且分布均匀,并且随着问题规模的增加,运行时间呈线性增长。

The existing service selection algorithms have defects such as inefficient, non-global optimization.For overcoming the defects,this paper proposed an efficient service selction algorithm,IDMPSO based on services’ QoS.Firstly,modeled the service selcetion as multiple objective optimization problem.Then,designed an improved multiple objective particle swarm optimization algorithm to solve the above problem, and obtained a group of high-quality solutions at last.In IDMPSO,employed crowding-measure to maintain Pareto optimal solutions and adopted a new meathod to find global optimal particles.The experiment results show that IDMPSO can obtain enough, good distribution solutions and its running time increases linearly with the problem size.