中文摘要：

考虑到快递配送和物流配送的异同,在物流配送路径优化问题的基础上构建了符合快递配送路径优化问题的数学模型.设计了一种采用自然数编码,综合考虑快件数量、车辆载重、车辆容量等约束的解码方式的遗传算法.通过一个拥有20个配送点的快递配送案例,验证本文所构建模型和算法能够得到合理配送路径和各个配送点的服务时刻.最后通过灵敏度分析和四轮厢式货车算例验证表明：当前情况下,研究快递配送路径优化时,快件数量、快递员最长配送时间和各配送点的作业时间必须考虑;当前快递配送车辆的载重和容量满足当前需求,无需更换载重和容量更大的配送车辆.

英文摘要：

Given the differences between express distribution and logistics distribution, this paper establishes a mathematical model in line with routing optimization problem of express distribution. In order to solve the model, a genetic algorithm is designed that uses natural number coding and the decoding style fully considering express number constraint, vehicle load constraint, and vehicle capacity constraint. By validating an express distribution case with 20 customer points, the results show that：the model established and the algorithm designed in the paper can obtain reasonable distribution paths and service time for each customer distribution point. Finally, the results of sensitivity analysis and four-wheeled van example show that： in current actual situation, courier＇s maximum distribution time and express operated time each distribution point should be considered in studying on route optimization for express distribution; the existing vehicle load and capacity can meet requirement of express distribution in the current situation, and no need to replace distribution vehicle with a larger load and capacity.