考虑车辆限速区间和风险公平性的危险品运输网络优化

On the approach to optimizing the transportation network of the hazardous materials on account of the vehicle speed limit intervals and the risk equity

针对有路段风险约束的危险品运输网络优化问题,讨论了不同路段上车辆限速区间的变化对危险品运输风险和成本的影响。基于最小最大准则构建了双层规划模型:上层规划表示政府部门通过对不同路段设置不同的限速区间来最小化最大运输网络总风险和路段最大风险的上界值,并通过增加路段最大风险的上界约束来实现风险分布的公平性;下层规划表示危险品运输商选择鲁棒成本最小的路径。为求解模型,设计了粒子群优化算法。根据算例分析发现,政府管理部门通过实施车辆限速区间策略,在考虑风险公平性的同时,可以有效地控制危险品运输网络的最大总风险。

The present paper is aimed to propose a speed limit interval strategy for the transportation of the hazardous materials or substances through the different links in hoping to minimize the risk of transport of such hazardous materials or any other goods.And,to optimize the transportation problem of such hazardous materials or goods with the related link risk constraints,we have first of all analyzed the limitations and restrictions of the former road restrictions and forbidden or heavy charge strategies for the sake of reducing the total cost and risk of such hazardous goods transportation as far as possible.And,secondly,efforts have also been made to classify and clarify the close relationship between the vehicular speeds and the traffic accidents,so as to make an analysis of imposing the different speed limits of hazardous goods vehicles on the different links in the hazardous materials transportation,which would bring enormous inconvenience for the route selection of such vehicles so as to result eventually in the different total costs and total risks in the choice of roads for such hazardous goods transportation.And,thirdly,the paper has also established a bi-level programming model for such goods transportation optimization based on the minimum and maximum decision criteria,in which the upper level inclination is to minimize the total risk of the transportation network and the upper bound of the maximum link risk by imposing the different speed limits on the different links,so as to win the risk equity by imposing the upper boundary constraints of the link risk.And,the lower level indicates that the hazardous materials carriers have to choose their own channels with the least robust costs.And,fourthly,we would also like to recommend the particle swarm optimization algorithm to solve the above model.And.last of all,we would like to propose a numerical example to verify the effectiveness of the model and the algorithm,so that,on the one hand,the government authorities should effectively practice for the control of the maximum risk of hazardous materials transportation network by implementing the speed limit interval strategy,whereas the equity of the risk distributions among the different links can be achieved by imposing the upper bound constraints of the maximum link risk so as to minimize the upper bound of the maximum link risk.