运输时间约束下冷藏集装箱海运网络优化

Optimization of refrigerated container shipping network considering transportation time constraint

以冷藏集装箱为研究对象,分析生鲜货物的易腐特性和时效要求对冷藏集装箱运输方案的影响,以运输总成本最小为目标、运输时间为主要约束,构建冷藏集装箱海运网络优化模型,研究不同供需组合和运输时间要求下的最优运输方案.算例结果显示,对于距离较近的起点-终点(OD)对,中转运输较直达运输的运输时间平均增长60%以上,运输成本增长15%以上,故选择直达运输.对于距离较远的OD对,中转运输可实现规模经济效益,为最优运输方案.运输时间约束的敏感性分析显示,短途运输对于运输时间约束变化不敏感,直达运输相较中转运输可节约运输成本10%以上,故均选择直达运输;长途运输受运输时间约束影响较大,仅在满足条件时才选择中转运输,否则只选择直达运输.

Taking refrigerated container as the research object,the effect of perishable characteristics and aging requirements of fresh goods on the transportation plan of refrigerated containers is studied.With the aim of minimizing the total cost and transportation time as the main constraint,a refrigerated container shipping network optimization model is established to ensure the optimal transportation plan under different combinations of supply and demand and transportation time requirement.The example results show that for origin and destination（OD）with short distance,transportation time of transit transportation increases by more than 60% compared with direct transportation, while the transportation cost increases by more than 15%,so direct transportation is selected.For OD with long distance,transit transportation is the optimal plan,which can achieve economies of scale.The sensitivity analysis of transportation time constraints shows that short distance transportation is insensitive to the change of transportation time constraints,and the transportation cost of direct transportation can be reduced by more than 10% compared with transit transportation,so direct transportation is always chosen when the condition is satisfied.While long distance transportation is greatly influenced by transportation time constraints,only when the transportation time constraints are met can transit transportation be chosen,or it can only choose direct transportation.