| Railroads face the challenge of competing with the trucking industry in a fast-paced environment. In this respect, they are working toward running freight trains on schedule and reducing travel times. The planned train schedules consist of departure and arrival times at main stations on the rail network. However, this plan does not consider the conflicts that occur as the trains meet along the tracks between these main stations. A detailed timetable, on the other hand, consists of the departure and arrival times of each train in each track section of its route. The train dispatching problem aims to determine detailed timetables over a rail network in order to minimize deviations from the planned schedule. In this paper, we provide a new integer programming formulation for this problem based on a space-time network; we propose heuristic algorithms to solve it and present computational results of these algorithms. Our approach includes some realistic constraints that have not been previously considered as well as all the assumptions and practical issues considered by the earlier works. |
