An integer linear program to combine container handling and yard crane deployment

Abstract

The number of containers handled by container terminals has increased significantly over the last fifty years and has stimulated researchers to improve storage yard operations. Container handling and crane deployment are two major yard operations that can impact the performance of a whole container terminal. This thesis establishes an Integer Linear Program (ILP) to combine container handling and yard crane deployment for Rubber Tired Gantry Cranes (RTG). Using real world data, we test the ILP for two different yard sizes. We find the resulting ILPs difficult to solve directly. In order to decrease the computation time, we apply a cascade method that solves the problem as a sequence of restricted subproblems. Each subproblem is restricted to a sequence of containers and the output of each subproblem provides an input to the next subproblem. This method provides better solutions than the solution that we get by solving the problem directly. The cascade method also decreases the computation time significantly. The results demonstrate the ability to combine container handling and yard crane deployment in a single model and they verify that the cascade method works well with the ILP.