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This paper deals with a realistic multi-period liner ship fleet planning problem by incorporating stochastic dependency of the random and period-dependent container shipment demand. This problem is formulated as a multi-period stochastic programming model with a sequence of interrelated two-stage stochastic programming (2SSP) problems characterized ship fleet planning in each single period. A solution method integrating dual decomposition and Lagrangian relaxation method is designed for solving the developed model. Numerical experiments are carried out to assess applicability and performance of the proposed model and solution algorithm. The results further demonstrate importance of stochastic dependence of the uncertain container shipment demand. 相似文献
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Given a fleet of container ships of varying capacity, a cost-efficient approach for improving fleet utilization and reducing the number of delayed containers is to optimize the sequence of container ships in a given string, a problem which belongs to the large ship-deployment class. A string sequence with ‘uniformly’ distributed ship capacity is more likely to accommodate a random container shipment demand. The number of one’s total ship slots acts as a gauge of the capacity of the container ships. Meanwhile, there are two types of ship slots: dry slots and reefer slots. A dry slot only accommodates a dry container, while a reefer slot can accommodate either a dry or a reefer container. The numbers of dry and reefer slots for ships in a string are different. Therefore, in this study, we propose a model that considers both dry and reefer slots and use it to elucidate the optimal ship-deployment sequence. The objective is to minimize the delay of dry and reefer containers when the demand is uncertain. Furthermore, based on the optimal sequence deduced, the study also investigates the need to convert some dry slots to reefer slots for the container ships. 相似文献
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Calwin S. Parthibaraj PL.K. Palaniappan Angappa Gunasekaran 《Maritime Policy and Management》2017,44(6):705-726
The support of containerization to trade development demands an efficient solution method for the container loading problem in order to reduce shipment and handling time. Hence, the stowage planning of containers is critical to provide speedy delivery of resources from the area of supply to the area of demand. Moreover, information on container terminal activities, structure of ship, and characteristics of containers is distributed among stowage planners. This information imposes constraints, and so the master bay plan problem (MBPP) becomes NP-hard. Therefore, a multi-agent systems (MAS) methodology is designed to effectively communicate the information and solve the MBPP sustainably. In the designed MAS methodology, an information exchange system (IES) is created for stowage planners to bid for ship slots in each experimental iterative combinatorial auction (ICA) market. The winner in the ICA experiments is provided with the ship slots, and the entire bay plan is prepared. Further, the ship-turnaround time is validated using the data obtained from the benchmark problem. 相似文献
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Ship slot capacity is the main sale resource of container shipping lines. However, shipping lines often encounter situations, such as serious ship delays, that require adjustments of shipping schedules, causing the original delivery plans of some consignments to be altered. This study proposes an integer programming model for slot reallocation planning, based on a given adjusted schedule. Decisions regarding empty container repositioning are also examined. This model aims to maximise a company’s benefits from deliveries of consignments and movements of empty containers. Available slots are subject to port rotation changes, allowable port handlings and ship capacity. A case study of a deep ocean loop demonstrates optimal slot reallocation, and empty container repositioning is used for illustrative purposes. The reallocation characteristics due to benefit items and the model’s applicability to large-scale examples are discussed. 相似文献
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为了提高船舶中小组立等中间产品建造作业调度能力,提升船舶建造效率,提出面向多约束的船舶组立建造作业调度方法。首先,分析船舶组立建造的工艺流程和作业调度方法,综合考虑机器小组、工艺和交货期等多种约束条件,以建造周期最短为调度目标,建立船舶组立建造作业调度数学模型;其次,综合运用算法分解策略及调度规则,设计改进的最短作业优先调度算法实现模型求解;最后,以某船厂建造车间一定生产周期(17天)的中小组立先行中日程计划为对象,验证该方法的有效性和实用性。研究结果表明,所提出的面向多约束的船舶组立建造作业调度方法相较于当前的调度方法,排产周期压缩22小时,即缩短了原有周期的16.18%,有效提高了生产计划排产和作业调度效率。 相似文献
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ZHANG Wei-ying LIN Yan JI Zhuo-shang 《船舶与海洋工程学报》2005,4(3):30-36
In a general case, container ship serves many different ports on each voyage. A stowage planning for container ship made at one port must take account of the influence on subsequent ports. So the complexity of stowage planning problem increases due to its multi-ports nature. This problem is NP-hard problem. In order to reduce the computational complexity, the problem is decomposed into two sub-problems in this paper. First, container ship stowage problem (CSSP) is regarded as “packing problem”, ship-bays on the board of vessel are regarded as bins, the number of slots at each bay are taken as capacities of bins, and containers with different characteristics (homogeneous containers group) are treated as items packed. At this stage, there are two objective functions, one is to minimize the number of bays packed by containers and the other is to minimize the number of overstows. Secondly, containers assigned to each bays at first stage are allocate to special slot, the objective functions are to minimize the metacentric height, heel and overstows. The taboo search heuristics algorithm are used to solve the subproblem. The main focus of this paper is on the first subproblem. A case certifies the feasibility of the model and algorithm. 相似文献
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ABSTRACTAccurately estimating fuel consumption of ships is crucial for shipping companies, port authorities, and environmental protection agencies. The bottom-up approach is becoming increasingly popular because it can estimate ship fuel consumption by accounting for ship activity conditions, such as changes in voyage speed, time, and distance; however, its use is still limited when estimating ship fuel consumption. Ship-specific information, such as the daily fuel consumption rate for main and auxiliary engines for every vessel, is expensive to gather, and generally not collected from private shipping companies. To address this research gap, we develop simplified and composite ship fuel consumption models for ocean-going container ships by size using a regression model. To estimate the fuel consumption models for container ships, we rely on ship activity data, including average speed and sailing time, distance, and actual fuel consumption for main and auxiliary engines. This information is obtained from a major container shipping company in Korea. We estimate and validate the parameters associated with fuel consumption for five different container ship sizes, all of which are smaller than the Post-Panamax container ship (15,000 TEU and above). 相似文献
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ZENG Qing-cheng YANG Zhong-zhen 《船舶与海洋工程学报》2007,6(2):44-50
An optimization model for scheduling of quay cranes (QCs) and yard trailers was proposed to improve the overall efficiency of container terminals. To implement this model, a two-phase tabu search algorithm was designed. In the QCs scheduling phase of the algorithm, a search was performed to determine a good QC unloading operation order. For each QC unloading operation order generated during the QC's scheduling phase, another search was run to obtain a good yard trailer routing for the given QC's unloading order. Using this information, the time required for the operation was estimated, then the time of return to availability of the units was fed back to the QC scheduler. Numerical tests show that the two-phase Tabu Search algorithm searches the solution space efficiently, decreases the empty distance yard trailers must travel, decreases the number of trailers needed, and thereby reduces time and costs and improves the integration and reliability of container terminal operation systems. 相似文献
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流域船闸群的联合调度因其影响因素多、过程复杂,一直采用人为调度和排档,没有形成一体化智能调度系统。通过对船闸调度影响因素和调度策略进行研究,将传统靠人为判断的多船闸调度决策抽象为时间上的时间表(timetable)问题和空间上的装箱(bin packing)问题的相互耦合问题,进而给出具体的调度算法流程。并以此为基础,设计信江流域的双港、八字嘴、界牌船闸三个梯级一体化调度方案,利用智能算法自动生成流域多船闸一体化计划。结果表明,本流域船闸群一体化调度系统在实践中取得良好的应用效果,可以有效提高调度智能化水平和通航效率。 相似文献
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集装箱船特点是线型变化大、精度要求高,相对于其他常规船型,建造难度较大.针对造船领域集装箱船建造方案策划所需考虑的多种因素,进行研究探讨,以3600 TEU集装箱船为例,介绍集装箱船建造方案策划的各项举措,保障项目成功实施. 相似文献
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Patrick Alderton 《Maritime Policy and Management》2013,40(4):329-330
This article deals with a short-term Liner Ship Fleet Planning (LSFP) problem with cargo shipment demand uncertainty for a single liner container shipping company. The cargo shipment demand uncertainty enables us to propose a chance constraint for each liner service route, which guarantees that the liner service route can satisfy the customers’ demand at least with a predetermined probability. Assuming that cargo shipment demand between any two ports on each liner service route is normally distributed, this article develops an integer linear programming model with chance constraints for the short-term LSFP problem. The proposed integer linear programming model can be efficiently solved by any optimization solver such as CPLEX. Finally, a numerical example is carried out to assess the model and analyze impact of the chance constraints and cargo shipment demand. 相似文献
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针对港池内船舶装卸作业的安全与稳定问题,采用基于势流理论的面元法分析程序AQWA,分析得到船舶与码头结构耦合作用下的14 000 TEU集装箱船动力响应幅值算子。在此基础上,进一步采用码头泊位前的真实波浪条件,得到14 000 TEU集装箱船在设计系缆方式下的船舶运动量响应和缆绳受力响应。结果表明,14 000 TEU集装箱船横摇周期较大,与港池内存在的中长期波(12~18 s)不相匹配,不易引起船舶较大幅度的动力响应;计算分析结果与系泊物理模型试验所得到的结果相吻合,说明所采用的计算原理与分析模型较为可靠,具有较强的工程实际应用价值。 相似文献
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J.-D. Caprace C. Petcu M. G. Velarde P. Rigo 《Journal of Marine Science and Technology》2013,18(3):404-417
In this article we describe the development of a tool that allows planners to efficiently and effectively plan space within valuable areas of a shipyard. Traditionally, space is considered as resource; however, it is difficult to accurately account for and plan its consumption with the currently available planning software’s. The spatial scheduling tool described in this article can be used by planners to manually or automatically reserve space within the shipyard for construction of large blocks over the entire erection period of the ship. The software is coupled with a heuristic optimization solver inspired by an algorithm used for "3D bin-packing problems." The result is the ability to efficiently generate and compare multiple space allocation alternatives in a reduced time with the ultimate goal of maintaining the critical ship erection schedule. A better solution than manual or semi-automatic allocation of blocks can be obtained through the optimization module. 相似文献