This paper considers a generalized version of the planar storage location problem arising in the stowage planning for Roll-on/Roll-off ships. A ship is set to sail along a predefined voyage where given cargoes are to be transported between different port pairs along the voyage. We aim at determining the optimal stowage plan for the vehicles stored on a deck of the ship so that the time spent moving vehicles to enable loading or unloading of other vehicles (shifting), is minimized. We propose a novel mixed integer programming model for the problem, considering both the stowage and shifting aspect of the problem. An adaptive large neighborhood search (ALNS) heuristic with several new destroy and repair operators is developed. We further show how the shifting cost can be effectively evaluated using Dijkstra’s algorithm by transforming the stowage plan into a network graph. The computational results show that the ALNS heuristic provides high quality solutions to realistic test instances.

本文考虑了滚装船的积载计划中出现的平面存储位置问题的广义形式。船舶设置为沿着预定航程航行，在该预定航程中，将沿着该航程在不同的港口对之间运送给定的货物。我们旨在为存储在船甲板上的车辆确定最佳的装载计划，以使为使其他车辆能够装卸（换挡）而花费的时间减少到最小。考虑到问题的存储和转移方面，我们提出了一种新颖的混合整数规划模型。自适应大邻域搜索（ALNS）启发式与几个新的破坏和修复算子被开发。我们进一步展示了如何使用Dijkstra的算法通过将装载计划转换为网络图来有效地评估转移成本。计算结果表明，ALNS启发式算法为现实的测试实例提供了高质量的解决方案。