Robust Optimization Model For Liner Ship Fleet Deployment With Slot Co-charter Under Shipping Alliance

As the integration of COSCO and CSCL and the bankruptcy of Hanjin shipping,the global shipping alliance begins reshuffle—restruction of the alliance,redistribution of the lines,in addition,slot co-charter is the most common form of cooperation in the alliance,which promoted the necessity of research on the liner ship fleet deployment and slot co-charter problem under the background of liner shipping alliance undoubtedly.In the foreseeable future,the supply-demand imbalance of transport capacity in the main lane will maintain as an ordinary state,therefore,it is particularly important for the liner shipping company to deploy its ship taking into account slot co-charter properly in order to control the costs and maintain its market share.Fleet deployment decisions are usually made on the basis of the demand is known in previous studies.However,in the real world,container marine transportation condition is usually complex;demand is often difficult to know due to some uncontrollable factors.Thus,dealing with the impact of uncertain demand factors on the fleet deployment problem rationally has become an important issue in the industry.This paper proposes a liner ship fleet deployment with slot co-charter problem by taking into account container shipment demand uncertainty.Given a liner shipping service network comprising a number of ship routes,the problem is to determine the numbers,types and sailing speed of ships required in the fleet and how many slots to charter in and out on each route,and then assign each of these ships to a particular ship route for the minimum expected total cost over the planning horizon after the size and mix of the fleet is determined.This paper thus formulates a certainty model,and then combined with the realistic planning problem as a robust linear programming model,which can deal with fleet deployment with slot co-charter problem under container shipment demand uncertainty efficiently and can be solved by a standard integer programming solver such as CPLEX.Finally,a numerical example is used to evaluate the performance of the proposed model.By adjusting the value of the budget of uncertainty and the deviation factor,the model is demonstrated that to be robust and scientific.Guarantee that the liner shipping company can deal with short-term fleet deployment with slot co-charter problem feasibly and rationally under demand uncertainty.