Study On Hazmat Transport Network Optimization Based On Economic Measures

In modern society, hazmat plays an important role in industrial and agricultural production, as well as improves the development of national economy. In the production and utilization of hazmat, the road guarantee of transportation is a key link. In the course of transportation, accidents could bring about a series of serious consequences. With the profound lessons brought by numerous accidents of hazmat transport both at home and abroad, how to optimize hazmat transport network and how to effectively control the risks develop a very important theoretical value and economic significance. Based on the equilibrium and laws for the statuses of hazmat transport network, this paper analyzes the effects of governmental economic management measures on risk mitigation and the vehicle operating. The work of this paper is shown as follows:Firstly, for the hazmat transport network design problem based on tolling, this paper proposes a bi-level programming model. This model sets a goal of minimizing total risks and time cost, considering the crowding effect between vehicles on links, and the risks of social vehicles brought by hazmat. In addition, the tolls for hazmat vehicles on some links are decided by the government, while paths can be chosen with freedom for all vehicles. Moreover this paper designs a corresponding algorithm according to the model characteristics, and analyzes the consequences by the numerical example in the end.Secondly, for the hazmat transport network design problem based on subsidies, this paper proposes an optimization model. In this model, a cost game is developed between the government and hazmat shippers, with the assumption of only hazmat vehicles included in the network. The government will affect the path choices of hazmat vehicles through the subsidies on some links, in the aim of minimizing the total risks and total subsidies, taking the risk equilibrium and subsidy budget into account. In order to describe this problem, a bi-level programming model is proposed, and a corresponding heuristic algorithm is designed. Then two numerical examples are given to verify the model and algorithm, through which some consequences are obtained in the end.Finally, for the emergency center selection problem with subsidy in hazmat transport network, this paper proposes an optimization model, as a combination of the emergency center location problem and the routes selection problem of hazmat vehicles. The government sets a goal of optimization. The goal is making the exposure risk, total time cost and the coverage of emergency centers minimum. Then two decisions are also made by the government:the scientific decision-making of the emergency center location and the positive effects on the routes selection of hazmat vehicles with subsidies. Hazmat vehicles can choose paths themselves according to the travel cost. In order to describe this problem, a bi-level programming model is proposed, and a numerical example is given to analyze and verify the model.