A heuristic for retrieving containers from a yard

This paper presents a three-phase heuristic to solve for an optimized working plan for a crane to retrieve all the containers from a given yard according to a given order. The optimization goal is to minimize the number of container movements, as well as the crane's working time. After generating an initial feasible movement sequence, the second phase reduces the length of the sequence by repeatedly formulating and generating a binary integer program. With another mixed integer program, phase three reduces the crane's working time by adjusting the movement sequence through iterations. Numerical testing results show that the heuristic is able to solve instances with more than 700 containers, which is within the range of real-world applications. Moreover, the number of movements approaches the lower bound in most cases, and the resulting movement sequence is efficient.