文档介绍：集装箱装船顺序优化模型及算法研究
摘要本论文提出了一个用于集装箱装船顺序优化的动态整数规划模型。模型同时兼顾了集装箱在堆场中和在船上的摆放位置,并把集装箱在不同港口的装卸作业作为一个整体。在实现装船顺序最优化的同时该模型还可保证船只在不同荷载分布下的稳定性。模型的求解是一个离散的NP-hard问题,论文给出了用遗传算法解决该问题的算法框架,并通过正交因子试验探讨了算法参数的显著性和交互效应,从而大大缩短了算法在解决该问题时的运算时间。
关键词集装箱运输,装卸优化,倒箱,遗传算法
Modeling and Algorithm Study for Optimizing Container Loading Planning for Containership
Abstract
In this paper, a mathematical model is proposed for developing plans for loading containers on containerships. The mathematical model is formulated as a dynamic integer programming problem. The model integrates many factors, such as the storage policies, container ship stowage and the transfers at different terminals. As weight is one of the critical factors that the model deals with, the best solution can also satisfy the meta-centric height restriction of the container ship. Since the problem is known to be NP-hard, GA is chosen due to the relatively good results in reasonable time. Unique coding method, evaluation function, ic crossover and mutation operators are designed aimed at this problem and the significance and interactive effect of different parameters settings used during operation are analyzed. The paper shows that by using orthogonal fractional experimental designs, a good GA structure can be achieved to solve a large, computationally intensive schedule problem.
Key words: Container Transfers, Loading-unloading Optimization, Setup Arrangement, ic Algorithms
1 引言
近年来,全球集装箱的运输量增长迅猛。1990到1999年10年间,%%。为了获得规模经济的优势,各航运公司也不断采用越来越大的集装箱运输船舶。当前营运中的最大集装箱船舶可载箱6000~7000TEU,甲板上的载箱列数为17列。而设想中的超大型集装箱船舶更达到了载箱18000TEU,列数超过20列的规模。随着船舶装卸集装箱数量的增加,其在港口停留的时间也越来越长,往往一艘船在其运输网络中的一个节点就要装卸上千个集装箱,服务时间长达5、6个小时,乃至一天。
根据调查表明,在集装箱装卸的过程中,由于港口的平面布置,设备配备,船舶属性都是固定的,“倒箱”次数的多少将是影响装卸服务时间的决定性因素。为了提高堆场的储存能力,堆场中的集装箱往往要堆3~7层高,而船舶上的集装箱往往也分6、7层摆放。如果要装卸的集装箱不是放在最上层,倒箱操作就在所难免。虽然倒箱一次的时间相对于整个搬运时间来说很短,但随着规模经济的发展,堆场和船只中集装箱堆放数量将会不断增加,且堆放形式将更为紧凑,这就使得累积的因为倒箱而耗费的时间达到不可忽视的程度。,现有500只集装箱要装船,而其中30%需要倒箱的话,其额外作业时间就长达6