Simultaneous Allocation of Berths and Quay Cranes under Discrete Berth Situation
Abstract
This paper examines the simultaneous allocation of berths and quay cranes under discrete berth situation in container terminals. The berths of discrete type have been broadly applied in realistic production especially for the terminals whose berths are not aligned in a straight line. The typical features of such berths including wharf length constraints, water depth constraints, and berth-bound quay cranes have been considered in this paper. In contrast to the previous work which only deployed the number of quay cranes besides the assignment of berths, this paper assigns berths and quay cranes simultaneously. In addition, to better fit the realistic production, some practical features related to quay cranes including the interference between quay cranes, the berth-dependent productivity of quay cranes, and limited adjustments of the assigned quay cranes during operations have also been considered in this paper. An integer programming model is formulated for this problem, and a sub-gradient-based Lagrangian relaxation algorithm is proposed. A simple but efficient greedy insertion heuristics is developed to solve the decomposed primal problems to optimality. Based on actual data, numerical experiments are conducted to test the performance of the proposed algorithm.
