产业界已出现利用多台轨道式龙门吊同时作业以提升集装箱码头装船效率的情况,由于需要确定每台龙门吊的取箱作业集合以及增加了"避免碰撞"、"顺次移动"等现实约束,故其移动路径规划问题在模型建立与求解上比单台轨道式龙门吊更为复杂。本文针对两台轨道式龙门吊同时作业的情形,建立了龙门吊移动路径网络模型,并开发了基于贪婪算法与动态规划的两阶段混合算法,并通过仿真算例,借助与基于实际调度规则所得到的调度方案的对比,验证了模型及优化算法的有效性与实用性。
This paper discusses the load scheduling problem of multiple yard cranes. The problem is to schedule two yard cranes at different container blocks which serve the loading operations of one quay crane so as to minimize the total distance of visiting paths and the make-span at stack area. A mathematical model,which considers interference between adjacent yard cranes,is provided by means of time-space network to formulate the problem and a two-stage hybrid algorithm composed of greedy algorithm and dynamic programming is developed to solve the proposed model. Numerical experiments show the effectiveness and practicability of the model and the algorithm in this study by means of the comparison with actual scheduling rules.