Abstract: For the lack of the standard of Particle Swarm Optimization algorithm to solve vehicle scheduling problem, this paper puts forward a Particle Swarm Optimization strategy which is based on a kind of integral coding. The strategy is based on the evolution-thought of Particle Swarm algorithm, gives the three-step optimal method. This paper refines the evolution way of the particle’s speed and position. With Floyd algorithm, it simulates the scheduling model and analyses it. The results show that the proposed strategy has good optimization ability.

Key words: vehicle routing problem, Particle Swarm Optimization（PSO）, three-step optimal strategy, integral coding

摘要： 针对标准粒子群算法在解决车辆调度问题上的不足，提出了一种基于整数编码的粒子群优化策略。它依据粒子群算法中粒子进化的思想，给出了三段式保优方法，重新定义了粒子进化速度和位置更新的方式。结合Floyd算法对调度模型进行了仿真验证分析。结果表明，该策略具有较好的寻优能力。

关键词: 车辆调度, 粒子群优化, 三段式保优策略, 整数编码