【作者】 李伟；

【导师】 杨延梅；

【作者基本信息】 兰州交通大学 ， 交通运输规划与管理， 2019， 硕士

【摘要】 随着我国经济产业链的结构调整,以大宗货物为主要运输产品的铁路运输市场面临着严峻的挑战,面对全国物流行业的激烈竞争,中国铁路总公司依托庞大的高速铁路网,积极开展高铁快运业务,以期在未来的物流行业中增强自身的竞争能力。高铁快运以其自身的特点可将客户所需货物快速的从出发地转移到目的地,提高了货物运输的时效性。为了进一步满足客户在城市末端物流配送的时效性要求,在深入研究分析目前城市末端物流配送的实际情况后,结合客户的实际要求,建立了带有软时间窗的城市末端物流配送路径优化模型。本文的主要研究内容如下:(1)针对目前高铁快运下的城市末端物流配送的发展现状,重点分析了高铁快运的组织模式、服务产品种类及城市末端物流配送的基本过程和目前存在的不足,指出城市末端物流配送环节的服务质量将直接影响高铁快运未来的发展。(2)针对城市末端物流配送的实际情况及客户对货物配送的时效性要求,引入软时间窗约束,限制配送车辆到达所服务对象的时间点,有效保证客户所需货物在其规定的时间段内完成交接,满足客户时效性要求,提高客户满意度。(3)明确了模型的目标。即根据客户的实际需求,建立配送总成本最小的目标函数。配送总成本由运输成本、拥堵成本和惩罚成本三者组成,其中拥堵成本主要是由于道路拥堵导致的额外支出成本。基于此建立了带有软时间窗的城市末端物流配送路径优化模型。(4)根据模型设计求解算法。本文设计了两种启发式算法:自适应性遗传算法和模拟退火算法与遗传算法结合,求解带有软时间窗的城市末端物流配送路径优化模型。(5)根据模型给出相应的算例,使用MATLAB软件应用所设计的两种启发式算法分别求解算例,并对所得计算结果进行对比分析,得出应用模拟退火算法与遗传算法结合可使所得结果更优,同时也验证了模型的可行性。更多还原

【Abstract】 With the structural adjustment of China’s Economic Industrial chain,the railway transport market,which mainly carries bulk goods,is facing severe challenges.Facing the fierce competition in the national logistics industry,China Railway Corporation,relying on the huge high-speed railway network,actively carries out the high-speed rail express business in order to enhance its competitiveness in the future logistics industry.With its own characteristics,high-speed rail express can quickly transfer the goods needed by customers from their origin to their destination,which improves the timeliness of freight transportation.In order to further meet the timeliness requirement of customers in urban terminal logistics distribution,an optimization model of urban terminal logistics distribution path with soft time window was established after in-depth study and analysis of the current actual situation of urban terminal logistics distribution,combined with the actual requirements of customers.The main contents of this paper are as follows:(1)In view of the current development situation of urban terminal logistics distribution under high-speed rail express,this paper focuses on the analysis of the organization mode,service product types,basic process and current shortcomings of urban terminal logistics distribution,and points out that the service quality of urban terminal logistics distribution will directly affect the future development of high-speed rail express.(2)In view of the actual situation of logistics distribution at the end of the city and the timeliness requirement of customers for goods distribution,the soft time window constraint is introduced to limit the time point when the distribution vehicles arrive at the service objects,effectively ensure that the goods required by customers are handed over within the prescribed time period,meet the timeliness requirement of customers and improve customer satisfaction.(3)The objectives of the model are defined.That is to say,according to the actual needs of customers,the objective function of minimizing the total cost of distribution is established.The total cost of distribution consists of transportation cost,congestion cost and penalty cost,among which congestion cost is mainly due to extra expenditure cost caused by road congestion.Based on this,an optimization model of urban terminal logistics distribution path with soft time window is established.(4)Design the solution algorithm according to the model.This paper designs two heuristic algorithms: adaptive genetic algorithm and simulated annealing algorithm combined with genetic algorithm to solve the urban terminal logistics distribution route optimization model with soft time window.(5)According to the model,the corresponding examples are given.Two heuristic algorithms designed by MATLAB software are used to solve the examples respectively,and the results are compared and analyzed.It is concluded that the combination of simulated annealing algorithm and genetic algorithm can make the results better.At the same time,the feasibility of the model is verified.更多还原