考虑箱区作业均衡的自动化码头集装箱船舶配载计划

在考虑箱区作业均衡的基础上,研究自动化码头集装箱船舶的配载计划问题.以堆场翻箱时间最小、集装箱水平运输时间最短以及堆场箱区作业不均衡水平最小为目标建立0-1整数规划模型.使用CPLEX工具精确求解5个不同规模的算例得到配载结果,并对比是否考虑箱区作业均衡的配载方案.结果显示5组算例的翻箱量均为0,有效地满足翻箱时间最小的目标.在配载计划中考虑箱区作业均衡,所得的箱区作业不均衡指数较不考虑箱区作业均衡有一定程度的降低,最高降低19.0个百分点,平均降低7.2个百分点.结果表明所提模型可有效解决自动化码头配载计划问题,保证箱区作业的均衡性,提升码头的装船作业效率.     

以自动化码头为中心的船舶配载优化

针对自动化码头船舶配载效率较低的问题,为了提高设备资源利用率,提出了一种基于船舶配载特点设计的固定集搜索（FSS）算法。首先,在考虑一般船舶配载原则的基础上,以桥吊作业计划为依据,引入箱区作业均衡因素,将最小化箱区翻箱量、总装船时间以及尽可能的箱区作业均衡作为目标,建立自动化码头船舶配载混合整数规划模型;其次,通过固定较优解中多次出现的元素来寻求最优解。实验结果表明,不同规模的实例下,FSS算法相较于Cplex,翻箱量和不均衡箱数分别平均减少了22.3%和11.7%,目标函数值平均优化了6.5%;所提固定集搜索算法与粒子群优化（PSO）算法、遗传算法（GA）和蚁群优化（PSO）算法相比,目标函数值平均优化了2.1%,凸显了FSS算法更高的配载效率。而为了增加案例的多样性,对箱区堆栈分布和比例进行了调整。在这个情况下,FSS算法的不均衡箱数相较上述三种算法平均减少了19.3%,设备资源利用率更高。     

基于网络流的自动化集装箱码头堆场空间分配

为解决自动化集装箱码头堆场空间分配问题,突出自动化集装箱码头堆场的布局特征以及制定堆存计划时的特点,将堆存计划视为一个具有时间和空间维度的网络优化问题,提出一种基于网络流的自动化集装箱码头堆场空间动态分配的模型,并使用禁忌搜索算法来求解。结果表明,通过该方法可以确保同一时间段内作业的进口箱和出口箱均衡的分配在箱区中,同时满足场桥的"重进重出"。最后对CPLEX和禁忌搜索算法求解的结果进行比较,证明了禁忌搜索算法的优越性。     

集装箱装船顺序的多目标整数规划优化模型

为了解决集装箱堆场装船顺序问题,根据集装箱船舶和配载的实际情况,考虑集装箱的航程,结合集装箱的装载位置,以集装箱堆场的翻箱率、船舶卸载时的翻箱率以及装船后的稳性为目标,建立了装船顺序的多目标规划模型,并基于粒子群算法构造了求解算法,通过MATLAB进行仿真实验,数据结果表明,该模型具有一定的的合理性与可行性。     

基于启发式算法的集装箱预翻箱问题仿真研究

关于根据已知的集装箱配载图对堆场的集装箱进行预翻箱速度优化问题,为减少倒箱量,缩短船舶在港时间,以集装箱预翻箱过程为研究对象,对其进行仿真研究,达到提高集装箱码头装船效率的目的,提出了相应的启发式算法,并通过算例验证了算法的有效性.利用eM-plant软件分别建立了单贝位和多贝位的预翻箱仿真模型,通过对预翻箱过程仿真时间的统计验证了仿真模型的有效性,并与现有的启发式算法效能进行了比较,效果更好.仿真结果表明,改进方法可为解决目前集装箱堆场预翻箱问题提供了更有效的决策依据.     

不确定环境下码头堆场设备集成调度优化

集装箱码头堆场设备调度优化中,对确定条件下的内集卡和场桥的联合调度研究较多,且没有考虑外集卡的随机到达情况。考虑内集卡和场桥作业过程中的不确定性因素,包括：内集卡行驶速度,场桥行走速度和作业时间,并考虑外集卡随机到达堆场对于内集卡调度作业的影响,构建了不确定因素条件下的堆场设备集成调度优化模型,其优化目标是在考虑外集卡随机到达的情况下,最优化堆场设备的作业时间。设计了求解模型的粒子群算法,并比较了一般确定性模型和考虑不确定因素优化模型的结果。算例结果表明,所建立的模型和算法能有效真实地反映不确定因素对集装箱码头堆场设备作业的影响。     

考虑箱区利用率的出口箱资源配置启发式算法

作为集装箱运输的枢纽,堆场的管理是整个集装箱码头管理的重中之重。对出口集装箱堆场的资源配置研究可以提高出口集装箱的装载效率,提高集装箱码头堆场的作业水平。针对当前堆场资源配置研究中较少考虑箱区作业量平衡与码头运营成本关系的研究现状,在不同箱区作业量差异水平下,设计了以成本最低为目标的出口箱堆场资源配置启发式算法。进行了不同规模的算例实验,并进行了比较。     

自动化码头堆场穿越式双ASC调度

随着人工智能等科技的发展,海铁联运的运输模式加快了集装箱码头自动化的发展进程,自动化已经成为集装箱码头发展的必然趋势。对自动化集装箱码头堆场内可穿越式双自动堆垛起重机（ASC）在同一箱区内进行作业的过程进行研究,考虑不同大小的ASC的运行速度和单位时间内耗能不一样,以及在同一贝位两个ASC存在冲突的情况,建立多目标混合整数模型,得出完成所有集装箱任务的总时间和总耗能。并通过改变不同的参数来设计三组实验,实验结果表明,可以通过调整集装箱任务量、双ASC的速度、双ASC装载和空载的耗能之比来减少码头作业集装箱任务的总时间和总能耗。     

多场桥分区域平衡策划下的集装箱堆场箱位分配问题

集装箱码头堆场出口箱箱位分配和场桥调度对码头运营效率有重要影响. 为了合理分配箱位和调度场桥, 采用分区域平衡策划方法, 在给定批量任务下, 考虑场桥实际作业中的安全距离, 以均衡各场桥作业任务量和减少场 桥的非装卸时间为目标, 建立混合整数规划模型, 并设计遗传算法求解, 通过不同批量任务的实验分析验证所提出方法的有效性. 研究表明, 分区域平衡策划方法可以更好地解决箱位分配和箱区多场桥联合作业的优化问题.

     

考虑船舶稳定性的多港口集装箱配载问题

在海上集装箱物流运输中,配载计划是攸关集装箱运输安全、营运公司高效率和低成本的重要环节。集装箱配载计划主要包括两个决定因素,船舶的稳定性和集装箱的倒箱数量,对于停靠多港口的集装箱班轮来说,这两个因素通常是矛盾的,鉴于此,讨论了停靠多港口的集装箱运输班轮在整个航线上的配载计划问题,建立了问题的0-1规划数学模型,该模型将船舶稳定性作为约束条件,其目标是最小化集装箱船舶在整个航线所有港口的倒箱量;设计了求解问题的改进遗传算法并对仿真数据实例进行求解。仿真实验结果表明,与通常集装箱运输班轮采用的随机配载方式和按照目的港装箱的配载方式相比,该方法所得出的配载方案使得集装箱船舶在安全性和经济效益方面有明显的提高。     

港航多视角下内河集装箱船舶配载决策

为满足内河集装箱运输中船舶航线配载实际决策需求,从港方和船方多视角出发,提出港航多视角下船舶航线配载决策方法。基于问题分析与特征提取构建考虑港方和船方双方利益的港航多视角下的船舶配载决策模型。考虑到问题的多目标优化特性,设计一种带模糊关联熵的启发式算法进行多目标并行寻优。通过算例实验验证了模型与算法的可行性与有效性。     

Exact and approximate solutions of the container ship stowage problem

This paper deals with a stowage plan for containers in a container ship. Containers on board a container ship are placed in stacks, located in many bays. Since the access to the containers is only from the top of the stack, a common situation is that contianers designated for port J must be unloaded and reloaded at port I (before J) in order to access containers below them, designated for port I. This operation is called “shifting”. A container ship calling many ports, may encounter a large number of shifting operations, some of which can be avoided by efficient stowage planning. In general, the stowage plan must also take into account stability and strength requirements, as well as several other constraints on the placement of containers. In this paper we deal with stowage planning in order to minimize the number of shiftings, without considering stability constraints. First, a 0–1 binary linear programming formulating is presented that can find the optimal solution for stowage in a single rectangular bay of a vessel calling a given number of ports, assuming that the number of constainers to ship is known in advance. This model was successfully implemented using the GAMS software system. It was found, however, that finding the optimal solution using this model is quite limited, because of the large number of binary variables needed for the formulation. For this reason, several alternative heuristic algorithms were developed. The one presented here is based on a “reduced” transportation matrix. Containers with the same source and destination ports are stowed in full stacks as much as possible, and only the remaining containers are allocated by the binary linear programming model. This approach often allows the stowage planning of a much larger number of containers than using the exact formulation.     

Load scheduling for multiple quay cranes in port container terminals

This paper proposes a method to schedule loading operations when multiple yard cranes are operating in the same block. The loading scheduling methods in this paper are based on a genetic algorithm and a simulated annealing method, which consider interferences between adjacent yard cranes. It attempts to minimize the make-span of the yard crane operation. We consider the container handling time, the yard crane travel time, and the waiting time of each yard crane, when evaluating the makespan of the loading operation by yard cranes. An encoding method considering the special properties of the optimal solution of the problem is suggested. Numerical experiment was conducted to compare performances of the algorithms suggested in this study. Received: June 2005 / Accepted: December 2005     

Two-stage stochastic programming model for generating container yard template under uncertainty and traffic congestion

Yard template is a space assignment at the tactical level, which is kept unchanged within a long period of time and significantly impacts the handling efficiency of a container terminal. This paper addresses a yard template planning problem considering uncertainty and traffic congestion. A two-stage stochastic programming model is formulated for minimizing the risk of containers with no available slots in the designated yard area and minimizing total transportation distances. The first-stage model is formulated for assigning vessels in each block without considering the physical location properties of blocks, and the second-stage model is formulated for designating physical locations to all blocks. Subsequently, a solving framework based on genetic algorithm is proposed for solving the first-stage model, and the CPLEX (a commercial solver) is used for solving the second-stage model. Finally, numerical experiments and scenario analysis are conducted to validate the effectiveness of the proposed model and the efficiency of the proposed solution approach.     

基于动态平衡策划下的集装箱堆场箱位分配方案研究

针对集装箱在码头堆存时存在的箱位分配问题,在研究原有多场桥同时作业方案的基础上,提出了多场桥分区域动态平衡策划方案,弥补了原方案中因保证场桥间的安全距离而带来的缺陷。以合理利用堆存空间,提高场桥作业效率为目标,建立数学模型,结合遗传算法对所提方案进行验证。结果表明,分区域动态平衡策划方案能有效减少场桥的无效作业时间,提高场桥的工作效率,并能充分地利用堆场贝位,更好地利用堆场空间。     

考虑时间窗的集装箱港口场桥全局调度优化

合理高效的场桥调度计划有助于减少场桥与集卡相互等待的时间从而提高港口的运营效率,考虑到在实际操作中会出现多箱区多场桥同时工作、互相冲突等情况,建立了以场桥移动成本和延误成本最小化为目标的数学模型,利用计划时间段和时间窗的概念对场桥作业进行约束,通过遗传算法编码进行求解,并将计算结果与实际操作及其他算法的优化结果相对比,进而验证该模型和算法的有效性和稳定性。