Abstract: Sudden natural disastersare inevitable, but usually cannot be predicted in time, so emergency rescue work after disasters is particularly important. A feasible scheduling scheme is the key to ensuring the timely supply of emergency rescue materials. Scholars have done a lot of research and analysis on the scheduling of emergency materials during the emergency rescue period, and some literature has considered the phases of emergency rescue. However, the division of stages is not detailed enough to fully integrate the characteristics of each stage for material scheduling. And there is less consideration given to the issue of material transportation caused by the inability of emergency supplies to meet the needs of the affected areas in the later stages of emergency rescue.
According to the characteristics and priorities of each stage of the disaster emergency rescue period, considering the uncertain factors such as material demand and road damage,this paper proposes a multi-stage multimodal transportation scheduling framework of emergency materials. In the first stage, considering the strong timeliness of emergency rescue work, minimizing emergency material allocation time is taken as the optimization goal. In the second stage, material allocation time and satisfaction is taken as the optimization goal. In the third stage, considering the material dispatch demand, material allocation time, cost and satisfaction is taken as the optimization goal. Taking the number and load capacity of transportation vehicles, minimum demand satisfaction rate and transportation network damage as model constraints, the multimodal transportation scheduling model of emergency materials at each stage is constructed respectively. According to the characteristics of these model, a heuristic hybrid solution algorithm combining genetic algorithm and simulated annealing is proposed, which introduces the retention strategy of non-optimal solution of simulated annealing into the genetic algorithm, so that the evolved subpopulation and the potential excellent individuals in their neighborhood are combined again. It can not only further enhance the local search ability of the algorithm, but also maintain the strong global search characteristics of the genetic algorithm.
Taking the emergency rescue of Ya’an earthquake as an example, the effectiveness of the models and algorithm is verified. The algorithm iteration diagram for solving each stage model shows that the algorithm proposed in this paper can quickly converge to obtain scheduling results, including the multimodal transportation scheduling scheme considering the damage of the transportation network in the first and second stages, and the dispatch scheme from the dispatch areas to the rescue areas and the scheduling scheme from the rescue areas to the disaster areas in the third stage.
The innovation of this paper lies in: (1)According to the characteristics and work priorities of each stage of the emergency rescue period, a multimodal transportation dispatching model based on multi-stage is proposed, considering uncertainties such as material transportation needs and road damage ; (2)A heuristic hybrid solution algorithm combining genetic algorithm and simulated annealing algorithm is proposed according to the characteristics of the multi-stage emergency material dispatching model, and the effectiveness of the model and algorithm is verified by a real case.

Key words: uncertain decision-making, emergency logistics, multi-stage emergency material scheduling, multimodal transport

摘要： 切实可行的调度方案是保证应急救援物资及时供应的关键,应根据救援工作不同阶段的特点制订物资调度优化方案。本文根据各个救援阶段的工作重点, 考虑物资调运需求及路网中断等不确定性因素,提出了一个基于多阶段的应急物资多式联运调度框架。第一阶段以物资调度时间最小为目标,第二阶段增加物资满意度目标,第三阶段增加调度成本目标,分别构建了各阶段应急物资调度优化模型,并提出了遗传算法和模拟退火相结合的启发式混合算法进行求解。最后,以雅安地震应急救援物资调度为例,分别求得了应急救援各阶段的多式联运物资调度优化方案,验证了模型和算法的可行性。

关键词: 不确定决策, 应急物流, 多阶段物资调度, 多式联运