考虑货物时间价值的国际集装箱多式联运路径优化

Optimization on International Container Multimodal Transport Path Considering Time Value of Goods

为了降低国际集装箱多式联运的运输成本、提高运输效率,解决国际集装箱多式联运路径优化问题,在考虑货物时间价值的基础上,依次建立了运输成本节约模型、最短运输时间模型,以及整合运输成本和时间加权的双目标优化模型。传统Dijkstra算法在多式联运路径规划中存在局限性,分别从3个方面对该算法进行了改进——考虑有向带权重的连通图、循环多顶点标号和增加交通工具类型元素。选用某企业的集装箱运输数据进行了分析,研究了3种不同需求偏好下(时间偏好、均衡型偏好以及成本偏好)的最优运输路径,在此基础上探究了最优路径对年度运输总量的影响,通过与混合算法结果的比较充分验证了Dijkstra改进算法在解决多式联运问题中的可行性和有效性。结果表明:不同运输目标客户的需求偏好会影响多式联运最优路径的选择,进而影响运输成本、运输时效及年度运输总量;在成本权重和时间权重取值不同时,得到了3种不同的最优化路径选择方案;与混合算法运行的结果相比,Dijkstra改进算法的求解效果更优;只有更追求低成本时,混合算法才会略好于Dijkstra改进算法;在其他需求偏好下,Dijkstra改进算法下的运输时间更短,运输成本更低且最大时间节约率和成本节约率分别为30.86%和20.31%。

In order to reduce the transport cost and improve the transport efficiency of international container multimodal transport,and to solve the routing optimization problem of international container multimodal transport,the transportation cost saving model,the shortest transportation time model,and the dual-objective optimization model integrating transportation cost and time weighting are established.The traditional Dijkstra algorithm has some limitations in multimodal transport path planning,the algorithm is improved in three aspects:considering directed connected graph with weight,cyclic multi-vertex labeling and adding vehicle type elements.The container transportation data of an enterprise are analyzed,and the optimal transport path under 3 different demand preferences(time preference,equilibrium preference and cost preference)are studied,on this basis,the influence of the optimal route on the annual total transport volume is discussed,and the feasibility and effectiveness of the improved Dijkstra algorithm in solving the multimodal transport problem are fully verified by comparing with the result of the hybrid algorithm.The result shows that(1)the demand preference of different target customers will affect the choice of the optimal route of multimodal transportation,and then affect the transportation cost,transportation time and annual transportation volume;(2)when the cost and time weights are different,3 different optimal path selection schemes are obtained;(3)the improved Dijkstra algorithm is better than the hybrid algorithm;(4)the hybrid algorithm is only slightly better than the Dijkstra improved algorithm when it is more cost-effective;(5)the Dijkstra improved algorithm has a shorter shipping time under other requirements preferences,the transportation cost is lower,and the maximum time saving rate and cost saving rate are 30.86%and 20.31%respectively.