考虑延误与班期限制的多商品流多式联运方案优化

针对不确定时间影响的多商品流多式联运方案优化问题，以空铁联运为主，将运输时间转化为确定运输时间和不确定延误时间，同时考虑班期限制影响，以收货时间窗限制、准时率、运力等为约束条件，以所有订单总运输成本、运输时间和碳排放最小为目标，构建多商品流多式联运方案优化模型，并基于改进的非支配排序遗传算法Ⅱ(non-dominated sorting genetic algorithmⅡ,NSGA-Ⅱ)进行模型求解。实证分析表明：相对于无延误和班期限制，延误和班期限制均导致各目标值呈现不同程度增加；随着延误程度增加，总运输时间逐渐增加，而总运输成本还受到班期限制的耦合影响，呈现先减小后增加的周期性变化；碳排放量与运输成本呈现一致变化趋势；最后采用多属性决策方法获得考虑综合满意度的最优运输方案。研究结果可为实际中多式联运方案设计与优化提供参考。

Scheme Optimization of Multi-commodity Flow Multimodal transport Considering Delay and Timetable Restriction

For the optimization problem of multimodal transport scheme for multi-commodity flow with the influence of uncertain transport time, which mainly by air and rail combined transport,the travel time and transfer time are converted into definite transport time and uncertain delay time, while taking into account the impact of timetable restriction, and taking the delivery time window limit, on-time rate, capacity as the constraint conditions, and minimizing the total transportation cost, total transportation time and total carbon emissions of all orders as the objective, the model of multimodal transport scheme optimization for multi-commodity flow was constructed, and then the improved NASA-II algorithm is used to solve the model. The empirical analysis results show as follows. Compared with no delay and timetable restriction, the objective function values will increase to different degrees due to the influence with delay and timetable. With the degree of delay increases, the total transportation time increases gradually, as the total transportation cost is also affected by the timetable restriction, it shows a periodic change that first decreasing and then increasing. The carbon emission is shows a consistent trend of change with the transportation cost with the degree of delay increases. Furthermore, the transport scheme with the highest comprehensive satisfaction was obtained by the multi-attribute decision making method. The research results can provide reference for the design and optimization of multimodal transportation scheme in practice.