基于备选集的高铁快运专列开行方案优化

Optimization of train plan on high-speed railway immediate delivery based on candidate train set

以快运需求与列车服务最佳匹配为导向,根据高铁快运服务流程,构建考虑图定列车装载能力、停站方案、发车时间以及唯一性等约束的图定列车配装方案优化模型。模型以优化决策图定列车对于快运需求的服务方案为目的,以各站点剩余快运箱数量最少为优化目标。若图定列车难以满足快运需求,需以各站点剩余快运箱为研究对象,增开快运专列并对其开行方案进行优化。通过引入快运专列备选集,预先给定最大列车开行对数及其运行区段,建立考虑列车能力、车站能力、区段通过能力以及箱流守恒等约束的快运专列开行方案优化模型,综合决策快运专列开行对数、运行区段、停站方案以及箱流分配方案等内容。针对模型特点,设计包含增开、停开列车以及增加、减少停站次数等邻域解搜索策略的模拟退火算法,并提出专门的初始解生成以及箱流分配启发式策略。以兰新高速铁路为背景进行实例验证,结果表明,所提方法能有效满足各站点快运需求,解决快运箱的滞留问题,并且所得快运专列的开行方案效果良好,具有较高的箱流满载率及与各站点快运需求相耦合的停站方案。研究结果能有效解决快运需求与列车开行方案的匹配问题,有助于提高高铁快运服务水平和铁路企业经济效益。

Oriented by the best matching between express demand and train service, an optimization model for demand assignment was first constructed with a consideration of the train loading capacity, stop plan, departure time and uniqueness. The mathematical model captured the transport service plan of the scheduled(passenger)trains to express demand, with the minimization of the total number of remaining express boxes at all stations as optimization goal. If the total capacity of passenger trains cannot satisfy the express demand, the specialized express trains should be added and the train plan to serve the remaining demand should be optimized. By introducing the candidate train set, an optimization model of specialized express train plan was proposed to make decision for the operation pairs, operation sections, stop plan and demand assignment plan of the specialized express trains. The model considered the constraints of train capacity, station capacity, section carrying capacity and box flow conservation. According to the characteristics of the constructed model, an improved simulated annealing algorithm was designed with the neighborhood solution search strategies such as increasing and reducing the number of stops and the specialized express trains. Besides, a special heuristic strategy about the generation of initial solution and demand assignment was proposed. Finally, the correctness of the proposed model was further examined by numerical experiments based on Lanzhou-Wulumuqi high-speed rail corridor.The experimental results demonstrate that the proposed method can effectively meet the express demand and solve the retention problem of express boxes. In addition, the train plan has a high full-load rate, and the optimized stop plan can fit with the demand of each station. In summary, this paper effectively solved the matching problem between the express demand and train plan. The research findings are helpful to improve the service level of high-speed rail express and the economic benefits of railway enterprises.