双重服务水平约束下的第四方物流网络设计

Fourth Party Logistics Network Design under Dual Service Level Constraints

随着物流行业竞争的日益激烈,客户对第四方物流(fourth party logistics,4PL)网络的服务水平提出了新的要求,故如何在保证服务水平的情况下设计总成本最小的4PL网络具有重要的现实意义。客户需求满足情况一直是影响物流网络服务水平的重要因素。近些年来,随着人们生活节奏的不断加快,客户对物流的时效性越来越重视,时效性也成为影响物流网络服务水平的另一因素。本文的4PL网络服务水平为考虑时效性和客户需求满足情况的双重服务水平。为保证满足双重服务水平,本文以成本最小为目标,以时效性和客户需求满足情况为约束,建立了第四方物流网络设计模型。由于该问题具有NP难特性,本文提出了一种嵌入迭代局部搜索的自适应粒子群算法进行求解。不同规模算例的仿真实验结果验证了所提出算法的有效性。将本文模型与不加入时效性约束的第四方物流网络设计模型进行对比,实验结果验证了本文模型既能够有效满足客户要求的服务时间,又能够一定概率下满足客户的需求,从而保证网络的双重服务水平。

With the increasingly fierce competition in logistics market,customers have put forward new requirements for the service level of the fourth party logistics(4PL)network.Thus,it is very practical to consider how to construct a 4PL network that minimizes the overall cost while still guaranteeing the service level.The satisfaction of customer demand has always been a significant factor influencing the service level of the 4PL network.As the pace of people's life rhythm has continued to quicken,customers'attention has turned increasingly to the timeliness of logistics,which has become another factor influencing service level.Therefore,the dual service level was proposed in which both timeliness and customer demand satisfaction were taken into account.A 4PL network design model was established to minimize the overall cost.Timeliness and customer demand satisfaction were constraints in order to guarantee that the dual service level was fulfilled.Due to the NP-hard property of this problem,an adaptive particle swarm optimization algorithm embedded iterated local search was proposed.The effectiveness of the proposed algorithm was verified through numerical experiments on instances with different scales,and the effectiveness of the proposed model was also demonstrated by comparing the outcome of the model without the timeliness constraint.The experimental results show that the proposed model can meet the demand with a certain probability while meeting the service time,thus ensuring that the dual service level of the network is met.