Online routing of hazardous materials transportation based on risk equity

With the development of industrialized societies, the volume of production and transportation for hazardous materials (hazmat) is constantly growing. Since hazmat is an obnoxious item, the people on both sides of a road don\´t want them to pass this way. Therefore, how to spread the risk among the network evenly should be considered. This is so called "risk equity" problem. This paper considers a sequence of transportation tasks of the form "allocate a route of risk r from node s to node t", and develops a model whose goal is to minimize the maximum cumulative risk of edges in the network to spread risk and achieve equity. According to the actual situation, this is a typical on-line problem. Therefore, this paper designs an on-line algorithm, and get the competitive ratio.