MODEL FOR MEDIUM-TERM OPERATIONS PLANNING IN AN INTERMODAL RAIL-TRUCKSERVICE

This paper describes a model developed for medium-term operations plan ning in an intermodal rail-truck system. It was motivated by the need to redesign such systems to produce (1) more reliable service, (2) mul tiple service classes, and (3) better equipment and facility utilizati on. The model is an integer linear program, which is computationally d ifficult to solve. A heuristic procedure was developed which provides excellent solutions, generally within 1% of the known optimal solution to the relaxed (non-integer) problem. Thus the model and heuristic co uld be used on large networks. Uses of the model and possible extensio ns are briefly discussed. Copyright (C) 1997 Elsevier Science Ltd.