A Routing and Scheduling Algorithm for Radioactive Material Shipments

The United States Department of Transportation regulations for routing and scheduling of large quantity shipments of radioactive material acknowledge the relevance of route-specific parameters such as population density and activities, accident rates, time of day, and day of week. On the other hand, review of transportation analysis literature reveals little work in analytical techniques for optimization of routes and schedules based or. sucit characteristics. To address this deficiency, a model and a corresponding algorithm have been developed to optimize analytically paths and schedules through networks described by route-specific, time-varying parameters. A computer code incorporating the algorithm has been developed and successfully tested. The algorithm and the corresponding computer code consider deterministic time-ofday variation of parameters (e.g., traffic speed and density during rush hours on urban road networks) for individual network arcs. The relative importance of arc parameters can be selected by altering their weighting factors in the objective function. The code is structured to allow selection of addi tiona! or alternative optimization parameters and to permit modification for application to other hazardous materials shipments. The results of the analyses describe the optimum route(s) and departure time(s) for selected origin and destination nodes in a network.