An integrated container management model for optimizing slot allocation plan and empty container repositioning

This article proposes an integrated container management model to jointly optimize slot allocation plan for loaded containers and reposition for empty containers in a shipping network. The proposed model employs linear programming to formulate loaded and empty container shipping problems in a bi-level structure. In upper level the loaded container slot allocation plan aims to maximize operational profits for each service route; whereas in lower level the reposition of empty containers aims to minimize transportation costs for the entire shipping network. The surplus or deficient empty containers resulted from the upper problem are fed into the lower problem. To demonstrate the applicability of the proposed model, a real case of an intra-Asian short-sea container carrier is presented. The results show that the proposed model can serve as a decision support tool to facilitate the liner to ship the loaded and empty containers in a coordinative way.