共查询到20条相似文献,搜索用时 31 毫秒
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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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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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Dual cycling is an operation technique whereby quay cranes perform loading and unloading operations simultaneously in the same ship bay. In this article, a mixed-integer programming model for quay crane dual-cycling scheduling is developed. The model considers the stowage plan of outbound containers and the operation sequence of quay cranes. To solve the model, a heuristic method, called bi-level genetic algorithm, is designed. Meanwhile, a simulation optimization method integrating the intelligent decision mechanism of the optimization algorithm and evaluation function of simulation model is proposed. Numerical experiments indicate that dual cycling can reduce the operation time of quay cranes compared to the method of scheduling loading and unloading separately. Moreover, the model and algorithms developed in this article can tackle quay crane dual-cycling problem efficiently. 相似文献
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Containership stowage plans are a pivotal teaches in the system of container transportation. With the increasing containers shipping, planning containership stowage has become more and more complicated. So intelligent stowage planning for containerships is of great significance. An effective stowage plan may improve efficiency of transportation system. First, the progress of containership stowage plan at home and abroad is reviewed, including the latest developments, such as the application of various optimization methods and computer techniques to the problem. Then, the complexities of the problem are discussed and areas where investigations are still needed are pointed out. This will provide a reference for further research on the subject. 相似文献
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集装箱船配载过程中的重要环节是合理的箱位分配,它对保证集装箱船装载后的航行性能及其码头装箱效率有重要的影响.随着集装箱船的大型化及待装船箱量的增加,该问题的求解较为困难.结合集装箱船配载中箱位分配的实际操作特点,提出了利用与禁忌算法相结合的混合蚁群算法来求解集装箱的箱位分配问题.仿真模拟试验表明该算法能够在不影响装箱难度的同时,大幅提高集装箱装船后船舶的航行性能. 相似文献
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集装箱船舶实配过程的遗传算法解决策略 总被引:4,自引:0,他引:4
本文基于模糊优选的多目标优化遗传算法和隔离小生境技术的多峰函数优化遗传算法,建立了集箱船舶实配模型。计算机模拟的结构表明,计算结果符合工程要求,具有推广应用价值。 相似文献
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Cheng-Min Feng 《Maritime Policy and Management》2013,40(5):469-489
This paper addresses empty container reposition planning by plainly considering safety stock management and geographical regions. This plan could avoid drawback in practice which collects mass empty containers at a port then repositions most empty containers at a time. Empty containers occupy slots on vessel and the liner shipping company loses chance to yield freight revenue. The problem is drawn up as a two-stage problem. The upper problem is identified to estimate the empty container stock at each port and the lower problem models the empty container reposition planning with shipping service network as the Transportation Problem by Liner Problem. We looked at case studies of the Taiwan Liner Shipping Company to show the application of the proposed model. The results show the model provides optimization techniques to minimize cost of empty container reposition and to provide an evidence to adjust strategy of restructuring the shipping service network. 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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提出一种适用于集装箱船的冷藏集装箱集群测控方法。通过对冷藏集装箱单箱、冷藏集装箱集群和集装箱船舶的现状进行分析,研究设计一套基于硬件的船舶冷藏集装箱集群的测控系统,包括改良的蓝牙BLE5.0通信协议、系统通信数据字典、支持串口自供电的无线箱体模块、无线通信微基站和配置终端。开发完成产业化的成套产品,进行液化天然气(LNG)双燃料集装箱船的实船试验。在串口自供电设计方面,采用TxD双极性整流、电荷泵极性转换和双级电源供电,解决在取电电流仅为4 mA、使用时可供的脉冲电流高达18 mA的特种串口自供电电源的设计问题;在集装箱通信设计方面,实现不同品牌的冷藏集装箱的串口通信协议在会话层的嗅探解析;在冷藏箱集群的用电控制设计方面,为实现错峰供电,通过底层协议的控制,减少船舶电站容量,降低电站电流峰值。 相似文献
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MatrixVB组件在集装箱船舶配载系统开发中的应用 总被引:1,自引:0,他引:1
针对集装箱船舶配载系统开发过程中数据处理运算量大的要求,从MatrixVB组件和VB的特性出发,提出了运用VB与MatrixVB结合进行数据处理的技术。并以实例进行讨论,结果表明,此方法编程思路简单,是程序开发的很好方法。 相似文献
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朱国强 《交通部上海船舶运输科学研究所学报》2003,26(1):37-42
首先概要介绍近年来世界集装箱船大型化的发展,接着分析指出,远洋运输成本低廉是集装箱船大型化发展的驱动力,然后提出大型化发展中出现的3个问题值得讨论。第一个问题是大型化发展受港口航道水深、码头装卸机械等条件制约。第二个问题是设计制造超大型集装箱船的主机不易。最后一个问题是,为解决超大型集装箱船的巨量货物的“集疏运”,必须开发电子信息技术。作者最后提出,21世纪初对大型集装箱船的箱量定位应为8000标准箱。 相似文献
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Container vessels navigate among the world's ports, frequently passing through narrow and congested waters. Due to the many layers of containers on a container vessel's decks, it is difficult for the crew to be aware of all fishing vessels and other obstacles in a container vessel's radar observation blind zone. This greatly increases the risk of collisions and other accidents. Given such great challenges to safe navigation and safety management with container vessels, their security risks are severe. An effective visual monitoring system can improve the safety of the water area surrounding container vessel by eliminating a vessel's observation blind zone, providing an effective safety measure for vessels navigating fishing zones and other troublesome areas. The system has other functions, such as accident recording, ship security, and monitoring of loading and unloading operations, thus ensuring the ship operates safely. Six months' trial operation showed that the system facilitates safe navigation of container vessels. 相似文献
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Jiangbo Xing 《Maritime Policy and Management》2017,44(6):744-760
This paper focuses on the container rerouting due to a disruption, aims at making the optimal container flow recovery plan for the affected liner shipping company. First, we make the initial effort to bring up with a basic framework of disruption management for liner shipping. Second, we present a compact integer linear programming model for addressing the container rerouting problem under the proposed framework in a hub-and-spoke liner shipping network, based on a given recovery vessel schedule that determines to omit a port of call. Other shipping companies’ services and other modes (roadway, railway, and airline) as candidate alternative means to transport the miss-connected containers are also incorporated in the proposed model. The container flow recovery plan would select the optimal alternative paths for the miss-connected containers balancing the trade-off between container transport costs and delivery delay penalty costs. Finally, a case study from a global liner shipping company is investigated and the computational results indicate the model can be solved effectively and efficiently for the real-scale problem. Thus, the proposed approach in this paper can supply real-time decision support tool for the liner shipping operators on handling the process of container flow recovery. 相似文献
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在进行700TEU无舱盖集装箱的常规集装箱船方案设计的基础上,可两船型的完整稳性作了对比研究。结果表明:从满足稳性的要求出发,无舱盖集装箱船可以多装载集装箱的数量为总箱数的5% ̄10%,经济效益明显,本文还从满足无舱盖集装箱船货舱进水后稳性的残存衡准出发,探讨了确定排水舷口高度的方法。 相似文献