A Study On Robust Optimization Of Integrated Berth Allocation And Crane Assignment Problem In Container Terminals

As a junction of sea and land,container terminal plays an important role in international logistics.With the continuous development of container transportation,the resource optimization in container terminal has become a hot research issue.For container terminals,berths and quay cranes are two limited resources on the quay side.A reasonable schedule of berths and quay cranes can not only give full play to the loading and unloading capacity of the terminal,but also prevent the adverse effects of uncertain factors happened in the terminal.Based on the uncertainty theory,this dissertation studied the berth allocation and crane assignment problem and its robustness in stochastic environment,in order to provide theoretical support and practical reference for the optimization of container terminal scheduling.Based on the characteristics and boundary of the problem,this dissertation established an integrated berths and quay cranes scheduling model under definite environment considering the horizontal movement of quay cranes.According to the process of independent scheduling and integrated scheduling of those two resources,the corresponding construction methods were established and the effect of integrated scheduling on improving the service level of container terminal was verified by examples.Then,the genetic algorithm for this problem was devised,and the results of the genetic algorithm were compared with the results of other methods to test its adaptability in solving the problem.In terms of the robustness evaluation of berths and quay cranes schedule,based on the uncertainty theory,this dissertation devised a variety of robust evaluation indexes,analyzing the correlation between the robust evaluation indexes and the actual delay degree through the simulation experiments,the best index was selected under the current assumptions and arrival conditions.Based on this index,the slack time was introduced to improve the robustness of the schedule by adjusting the berthing positions and the crane sets.Since there was a conflict between the ship service and the robustness,this dissertation established a multi-objective model,and used NSGA-II algorithm to solve it.The change of Pareto front before and after the adjustment was obtained,which verified the effectiveness of the adjustment method.At last,this dissertation evaluated the ability of different robust schedules in absorbing disturbances under different disturbance levels,and evaluated the optimization effect of the robust model.