Optimization Model and Algorithm for Quay Crane Scheduling in Container Terminals

In order to remedy the defect of the traditional optimization methods for the quay crane scheduling in container terminal which could only deal with single ship, a mixed-integer programming optimization model for quay crane scheduling and job assignment for multiple ships was proposed. The objective of the model is to minimize the total cost, including the use cost of the quay cranes and the berthing cost of the ships in the terminal, with the non-crossing and safety distance constraints of cranes. Then, a bi-level simulated annealing algorithm with neighborhood search based on the restricted path was developed to solve the model, in which the job network graph is used to find the critical job and its restricted path that influence the end time of the ship unloading jobs. The results of 12 numerical experiments with different scales show that compared with the branch and bound (B&B) algorithm and the genetic algorithm (GA), the proposed algorithm could reduce the computational time by 6.32% to 18.36%, and obtain the approximate optimal solution of higher quality, the gaps between objective function values of which are only 0.38% to 2.20%In addition, considering the safety distance constraint between cranes into the model cause the total operation cost to increase by 3.41% to 11.21%.