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A Containership Routing Model for Hub-and-Spoke Networks
As the containerships are becoming increasingly larger, particularly the appearance of Ultra Large Containerships (ULCS), the problem with containership routing under the hub-and-spoke networks is becoming a more frequent issue. In this paper, a containership routing model for hub-and-spoke networks is presented. The model simultaneously determines the selection of hubs, the assignment of spokes to hubs, as well as containership routing between spokes and spokes, hubs and spokes, and between hubs and hubs. Since the problem is NP-hard, heuristic algorithms are proposed. The performance of the algorithms is tested through a set of examples and the computational results show the efficiency of the proposed algorithms. In the proposed algorithms, a new mechanism for cataclysm in genetic algorithms is introduced. Furthermore, the proposed algorithms also indicate a method of solving location routing problems. The developed model can be used as a decision support tool for shipping companies that provide a long haul shipping service under the hub-and-spoke network for dealing with routing decisions. In particular, for shipping companies that use ULCS to provide a transoceanic shipping service, this model can serve as a more helpful decision making tool. |