关键词: 第四方物流, 路径问题, 随机需求, 多种运输方式, 遗传算法

Abstract: Aiming at problem that customers demand is characterized by timeliness and regularity in Fourth Party Logistics (4PL),the Fourth Party Logistics Routing Problem (4PLRP) with stochastic demand and multiple transportation modes were researched by combining with the multiple transportation modes provided Third Party Logistics (3PL) providers in reality.With the condition that customer demand was random variable,the chance constrained program model was designed with the goal of minimizing transportation costs,which determined the transportation modes while selecting transportation routes and logistics 3PL providers.To solve the model,an Improved Genetic Algorithm (IGA) with embedded migration operator and elite strategy was designed.The algorithm parameters optimized by Taguchi experiments effectively improve the accuracy of solutions.The experimental results showed that with stochastic demand of customers,the transportation cost increased with the different confidence level,and joint transportation through multiple transportation modes could overcome the defects of single transportation mode and effectively reduce the transportation cost.The proposed algorithm had better global search capability and computational accuracy,and the IGA could solve the problem effectively.

Key words: fourth party logistics, routing problem, stochastic demand, multiple transportation modes, genetic algorithms