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1.
为改善单向航道连续泊位港口的运营效率,研究泊位分配与船舶进出港调度集成优化。考虑潮汐、进出港时段交替与偏好泊位的影响,建立0-1整数线性规划模型,以船舶偏离偏好泊位成本和滞期成本为优化目标,确定各艘船舶的靠泊位置与进出港时刻。针对问题情境和其特有的约束条件,将原数学模型通过Dantzig-Wolfe分解方法分成主问题模型和子问题模型,提出了满足问题特性的分支定界和列生成相结合的精确型分支定价算法。在列生成算法中,给出了适合本问题的列选取策略;在分支定界算法中,设计了广度优先策略来提升求解效率。采用多组算例来验证了方案与算法的有效性,并通过不同规模算例分析了进出港时段长度变化对方案的影响,可为港口的实际作业安排提供参考。  相似文献   

2.
泊位是船舶进出港调度中的重要组成部分。集装箱港口的泊位分配问题(BAP)是为到达集装箱港口的船舶安排最佳停靠位置和时间。考虑船舶动态到达的情况以及码头装卸效率对船舶在港作业时间的影响。以船舶的总在港时间最短为目标,包括船舶的等待时间和作业时间,建立了连续型泊位分配问题的求解策略。根据“先来先服务”的原则,构建了混合整数规划模型,并采用改进的遗传算法对其进行求解。经过算例结果的验证,该模型和算法被证明具有正确性和有效性,可以找到更符合实际情况的泊位分配策略。  相似文献   

3.
为了提高集装箱港口服务效率,减少船舶服务的拖期费用,针对港口硬件(泊位、拖轮、岸桥)既定条件下的拖轮-泊位联合调度问题,新建了以最小化总体船舶在港时间和总拖期时间为目标的数学模型,设计了一种混合算法进行求解。首先,分析确定了将量子遗传算法(QGA)和禁忌搜索(TS)算法进行串行混合的策略;然后,依据该联合调度问题特点,在解决算法实施中的关键技术问题(染色体结构设计和测量、遗传操作、种群更新等)的同时,采用了动态量子旋转门更新机制;最后,用生产实例验证了算法的可行性及有效性。算法实验结果表明,与人工调度结果相比,混合算法的总体船舶在港时间和总拖期时间分别减少了24%和42.7%;与遗传算法结果相比,分别减少了10.9%和22.5%。所提模型及算法不仅能为港口船舶的入泊、离泊和装卸作业环节提供优化作业方案,而且能增强港口竞争力。  相似文献   

4.
针对集装箱码头泊位确定条件下的单船岸桥(QC)分配和调度问题,建立了线性规划模型.模型以船舶在泊作业时间最短为目标,考虑多岸桥作业过程中的干扰等待时间与岸桥间的作业量均衡,并设计了嵌入解空间切割策略的改进蚁群优化(IACO)算法进行模型求解.实验结果表明:与可用岸桥全部投放使用的方法相比,所提模型与算法求得结果平均能够节省31.86%的岸桥资源;IACO算法与Lingo求得的结果相比,船舶在泊作业时间的平均偏差仅为5.23%,但CPU处理时间平均降低了78.7%,表明了所提模型与算法的可行性和有效性.  相似文献   

5.
针对集装箱船舶大型化导致的港口航道现有水深无法满足大型船舶安全吃水深度,需要借助潮水上涨进出航道的现状,研究了潮汐影响下连续型泊位和动态岸桥联合调度问题。建立了以最小化船舶周转时间和岸桥在船舶间移动次数的双目标混合整数规划模型。基于问题特点,设计了Epsilon约束精确算法和带精英策略的快速非支配排序遗传算法(NSGA-Ⅱ)分别求解小规模和大规模算例的Pareto最优解集,所得结果验证了模型和算法的正确性与有效性。通过潮汐周期灵敏度分析评估了潮汐周期长度对岸桥工作效率和港口服务质量的影响。仿真结果表明,建立的优化模型能够帮助港口企业有效降低潮汐对生产作业的影响,同时提供一组高效的Pareto最优泊位岸桥调度方案提高工作效率和经济效益。  相似文献   

6.
毕娅  李文锋 《计算机应用》2012,32(2):448-451
目前对港口和泊位的调度研究尚停留在单港口多泊位,而在集装箱港口集群条件下对多港口多泊位实行船舶的联合调度可以充分实现港口资源的优化配置。为了充分利用港口资源,实现船舶在港时间最短,且服从船公司运输成本最低的目的,建立了集装箱港口集群下多港口多泊位联合调度的多目标非线性决策模型,并按照模型决策空间所具有的特殊条件,设计了改进的遗传启发式算法,结果表明船舶靠泊成本大幅降低,港口利用率大幅提高。通过大量真实和随机算例验证了算法的有效性和稳定性,证明了模型和算法实用有效。  相似文献   

7.
在集装箱港口的运作中,泊位调试系统是制约集装箱港口降低船舶在港时间和运营成本的主要瓶颈之一。泊位调度的目标就是确定集装箱港口船舶的停靠泊位和停泊时间。将码头看成离散泊位的集合,以船舶的在港时间最短为目标,应用蚁群算法对该问题进行优经研究,在满足各种约束条件的基础上,充分的利用好码头资源。利用蚁群算法的正反馈和并行搜索特点提高解的质量2和稳定性,通过对某集装箱码头的案例分析,说明该算法的有效性和实用性。  相似文献   

8.
针对班轮企业由于提前公布船期表,但受货运需求的波动和潮汐的影响引起的多船型船舶调度问题进行研究。首先系统分析了一家班轮企业近洋运输航线结构;然后考虑大型船舶需乘潮进出港口,以及适当条件下允许租船的实际情况,兼顾班轮船期表的限制,构建了以运输总成本最小为目标的班轮多船型船舶调度非线性规划模型;最后考虑模型的特点,设计了嵌入基因修复的改进遗传算法(IGA)用于模型求解。实验结果表明,与传统的经验调度方案相比,得到的船舶调度方案在船舶利用率上能提高25%~35%;中规模算例下与CPLEX相比,IGA的CPU处理时间平均降低77%;中、大规模算例下与蚁群算法相比,IGA计算的运输费用平均降低15%。实验结果验证了所提模型和算法的有效性,可为班轮企业船舶调度提供参考。  相似文献   

9.
受恶劣天气影响的船舶调度是一个非常复杂的优化问题,也是班轮公司重点关注的问题之一。为此,针对某航运网络上的一家班轮公司的所有营运船舶,以获知设计的多阶段重调度机制时段内最新预报的天气信息和这些船舶的实时位置为前提,重点考虑班轮船期表的限制并兼顾港口间航速变化和船舶容量等现实约束,构建了以固定计划期内所有船舶的航运总成本最小为优化目标的非线性数学模型,并设计了嵌入基因修复算子的改进遗传算法用于求解该模型。由此,可以给出集成租船直运、跨航线调船、反挂和货物中转等解决策略的最佳多阶段重调度方案。通过对大、中、小规模的算例进行实验,实验结果表明,可知与传统等待办法相比,多阶段重调度节约了总航运成本的15%以上,验证了所提模型和方案的有效性;与Cplex相比,改进遗传算法的运算效率大大提高,且偏差值均在5%以内,而与蚁群优化(ACO)算法、禁忌搜索(TS)算法、量子差分进化(QDE)算法相比,改进遗传算法能在有效时间内降低10%左右的成本,验证了算法的科学性。所提方法可为班轮公司的实际船舶调度提供参考。  相似文献   

10.
在全球贸易经济聚焦在中国的同时,港口的吞吐能力成为目前港口业的主要矛盾。提高泊位这个环节的运作能力,减少船舶在港时间,增加港口的吞吐能力成为主要研究对象。本文采取仿真模型与优化算法相结合的研究方法,把泊位调度问题转化为旅行商问题,建立了一个泊位岸桥协调调度,通过蚁群算法建立数学模型,使船舶在港时间最短为目标建立函数,求得最佳调度方案。用ProModel建立船舶到港停泊及离港仿真模型。验证泊位调度优化的有效性,以便指导港口实际的泊位调度。  相似文献   

11.
A considerable growth in worldwide container transportation needs essential optimization of terminal operations. An operation schedule for berth and quay cranes can significantly affect turnaround time of ships, which is an important objective of all schedules in a port. This paper addresses the problem of determining the berthing position and time of each ship as well as the number of quay cranes assigned to each ship. The objective of the problem is to minimize the sum of the handling time, waiting time and the delay time for every ship. We introduce a formulation for the simultaneous berth and quay crane scheduling problem. Next, we combine genetic algorithm with heuristic to find an approximate solution for the problem. Computational experiments show that the proposed approaches are applicable to solve this difficult but essential terminal operation problem.  相似文献   

12.
Owing that the internal trucks (ITs) are frequently used as transportation equipments between yards and quaysides, the transportation efficiency of ITs secures a crucial position in container terminal productivity. Hence, a container terminal cannot contain a big number of ITs. As such, it is an imperative to explore an appropriate IT assignment strategy. Specifically for those container terminals with adjacent locations, an approach to sharing internal trucks among multiple container terminals (SIMT) is investigated. In this study, a novel strategy to resolve the SIMT problem was proposed for a specific large port with multiple adjacent container terminals. Firstly, an illustration of the SIMT strategy was presented. Then, an integer programming model for this problem is developed, where the objective functions are subject to the minimization of the total overflowed workloads and total transferring costs in every time-period among these container terminals. In particular, the rolling-horizon approach is employed for considering the immediate scheduling. Furthermore, a simulation optimization method, which integrates the genetic algorithm (GA) searching and simulation, is proposed for the near optimal solutions. Finally, the computational experiments are used to verify the effectiveness of the proposed SIMT strategy and simulation optimization method.  相似文献   

13.
In this paper, a simulation optimization method for scheduling loading operations in container terminals is developed. The method integrates the intelligent decision mechanism of optimization algorithm and evaluation function of simulation model, its procedures are: initializing container sequence according to certain dispatching rule, then improving the sequence through genetic algorithm, using simulation model to evaluate objective function of a given scheduling scheme. Meanwhile, a surrogate model based on neural network is designed to predict objective function and filter out potentially bad solutions, thus to decrease the times of running simulation model. Numerical tests show that simulation optimization method can solve the scheduling problem of container terminals efficiently. And the surrogate model can improve the computation efficiency of simulation optimization.  相似文献   

14.
This paper focuses on the container loading and unloading problem with dynamic ship arrival times. Using a determined berth plan, in combination with the reality of a container terminal production scheduling environment, this paper proposes a scheduling method for quay cranes that can be used for multiple vessels in a container terminal, based on a dynamic rolling-horizon strategy. The goal of this method is to minimize the operation time of all ships at port and obtain operation equilibrium of quay cranes by establishing a mathematical model and using a genetic algorithm to solve the model. Numerical simulations are applied to calculate the optimal loading and unloading order and the completion time of container tasks on a ship. By comparing this result with the traditional method of quay crane loading and unloading, the paper verifies that the quay crane scheduling method for multiple vessels based on a dynamic rolling-horizon strategy can provide a positive contribution to improve the efficiency of container terminal quay crane loading and unloading and reduce resource wastage.  相似文献   

15.
The maritime transportation flows and container demand have been increasing over time, although the COVID-19 pandemic may slow down this trend for some time. One of the common strategies adopted by shipping lines to efficiently serve the existing customers is the deployment of large ships. The current practice in the liner shipping industry is to deploy a combination of ships of different types with different carrying capacities (i.e., heterogeneous fleet), especially at the routes with a significant demand. However, heterogeneous fleets of ships have been investigated by a very few studies addressing the tactical liner shipping decisions (i.e., determination of service frequency, ship fleet deployment, optimization of ship sailing speed, and design of ship schedules). Moreover, limited research efforts have been carried out to simultaneously capture all the major tactical liner shipping decisions using a single solution methodology. Therefore, this study proposes an integrated optimization model that addresses all the major tactical liner shipping decisions and allows the deployment of a heterogeneous ship fleet at each route, considering emissions generated throughout liner shipping operations. The model’s objective maximizes the total turnaround profit generated from liner shipping operations. A decomposition-based heuristic algorithm is presented in this study to solve the model proposed and efficiently tackle large-size problem instances. Numerical experiments, carried out for a number of real-world liner shipping routes, demonstrate the effectiveness of the proposed methodology. A set of managerial insights, obtained from the proposed methodology, are also provided.  相似文献   

16.
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。  相似文献   

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