Model and Algorithm for Routing and Scheduling Problem in Hazardous Materials Transportation Network
To reduce the risks associated with hazardous materials transportation by optimizing routes and delivery schedules, a multiobjective routing and scheduling program with multiple time windows and time varying attributes in hazardous materials transportation network is studied. First, a mathematical model for this program is proposed and two punishing functions are introduced to the model for converting multiple time windows into the penalty variables of model. Second, a two-step solving algorithm for model is developed, and the first step of algorithm is to find the set of non-dominated paths with specific departure time from the origin based on the improved dynamic programming method, the second step is to identify the optimal alternatives from the non-dominated set by using the grey correlation analysis method. Finally, a case study is given to show that the model and algorithm can effectively solve the routing and scheduling program in hazmat transportation network, and can identify the optimal transportation paths for the decision maker.