Multi-task Container Transportation Optimization Problem Research Based On Node Replacement Time Uncertainty

Most studies have considered that the replacement time of a node is a fixed value.Because of the limitations of facilities,equipment,operation efficiency and management level of the transfer station,the replacement time of the node will change.The multi-modal operator should consider the impact of the change of the node replacement time on the choice of container transportation plan.Liner transportation is usually used in container waterway transportation,because the departure time of liner transportation is fixed and there is a limit on the number of available boxes.When multimodal transport operators organize multiple missions,these tasks may compete for a limited number of boxes.How to allocate the number of boxes reasonably is also a factor that the multimodal transporter needs to consider when making transportation options.This paper,from the perspective of multi-modal operators,considers the uncertainty of the reloading time of different modes of transportation and the characteristics of liner transportation on the choice of transportation mode and transportation route for multimodal transport operators.Objective to establish an integer programming model with time and capacity constraints,and design a multi-ant colony parallel algorithm to obtain the best multi-tasking container transportation scheme.According to the number of transportation tasks and the number of tasks,different types of calculation examples are designed,and the selection strategy of task priority is considered.According to the three strategies of large-scale first service,first-come first-served service and small-lot first service,limited liner boxes are selected.The number of digits is assigned,and the influence of various influencing factors on the optimal transportation scheme under different types of mission characteristics is compared and analyzed.The results show that the model algorithm is correct and effective,and can provide a theoretical reference for the decision of multimodal transport operators.The innovation of this paper is to consider the uncertainty of the reloading time,which is different from the fixed setting of the reloading time in the general problem.On this basis,this paper considers the time and capacity characteristics of the liner and adopts multiple task priority strategies assign transportation resources and has certain theoretical and practical significance.