Research On Optimization Of Reliable Path Of Multimodal Transportation Of Emergency Materials

Recently,landslides,mudslides,earthquakes,epidemics and other sudden disasters have occurred frequently,posing a huge threat to the transportation of emergency materials in China.If the transportation plan for emergency materials can be reasonably designed,and the emergency materials can be reasonably proportioned and beprovided on time,it can maximumlyensure the survival needs of rescuers and people in disaster areas when sudden disasters occur.Despite the improving comprehensive transportation network has laid thefoundation for multimodal transportation of emergency materials,factors such as climate,traffic,shift time and controlmanagement make it difficult to determine the transportation plan of multimodal transportation such as transportation time and transportation path.Therefore,it is important to construct a multimodal transportation path optimization model for emergency materials with the goal of maximum reliability and design a solution method to meet the requirements of emergency materials transportation,taking into full consideration the uncertainty of transportation environment,shift schedule limitation and transfer capacity limitation.Firstly,the transportation characteristics of emergency materials and the characteristics of multimodal transportation has been analyzed in this paper.Based on the basic solution of multimodal transportation path optimization for emergency materials,a multimodal transportation path optimization model for emergency materials considering shift restrictions and transshipment capacity restrictions under the determined environment has been constructed according to the idea from easy to difficult,and a heuristic algorithm has been designed to solve it.Secondly,for the problem of transport time and other changes caused by the change of transport environment,the reliability of the transport path has been found out from the perspective of reliability by using Monte Carlo simulation,and the reliable path optimization model of multimodal transport of emergency materials with the maximum reliability as the goal has been constructed.Then,a heuristic method has been designed for the NP characteristics of the model;and an application analysis test has been conducted with the arithmetic example,which shows that the departure schedule of railroads and waterways affects the multimodal transportation path optimization results,and the path optimization results are different for different departure moments.The designed optimization genetic algorithm has solved the emergency material multimodal transport path optimization problem better.The improved genetic algorithm designed in this paper can be used for the reliable path optimization solution of emergency material multimodal transport for the difficult NP characteristics of the emergency material multimodal transport path optimization model.The designed algorithm has solved the problems of illegal individuals generated in the process of encoding and crossover and mutation of general genetic algorithm and band circles,and the performance of the algorithm is The performance of the algorithm has been improved.The model and solution method of multimodal transportation for emergency materials in this paper can provide a reference for relevant enterprises to choose the best transportation route,and the research results further enrich the theoretical system of multimodal transportation planning and management.