Multi-agent system with iterative auction mechanism for master bay plan problem in marine logistics

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.     

混合蚁群算法求解集装箱箱位分配问题

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.     

Review of containership stowage plans for full routes

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.     

Optimal reefer slot conversion for container freight transportation

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.     

基于模拟减少集装箱船待港时间的实用方法(英文)

The main challenge for container ports is the planning required for berthing container ships while docked in port.Growth of containerization is creating problems for ports and container terminals as they reach their capacity limits of various resources which increasingly leads to traffic and port congestion.Good planning and management of container terminal operations reduces waiting time for liner ships.Reducing the waiting time improves the terminal’s productivity and decreases the port difficulties.Two important keys to reducing waiting time with berth allocation are determining suitable access channel depths and increasing the number of berths which in this paper are studied and analyzed as practical solutions.Simulation based analysis is the only way to understand how various resources interact with each other and how they are affected in the berthing time of ships.We used the Enterprise Dynamics software to produce simulation models due to the complexity and nature of the problems.We further present case study for berth allocation simulation of the biggest container terminal in Iran and the optimum access channel depth and the number of berths are obtained from simulation results.The results show a significant reduction in the waiting time for container ships and can be useful for major functions in operations and development of container ship terminals.     

Empty container reposition planning for intra-Asia liner shipping

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.     

Optimal container ship size: a global cost minimization approach

ABSTRACT

Currently, the best container ship size in a service is determined mainly by the liner operator, considering only the economies of scale of ships. Its external diseconomies to the ports and shippers are usually not considered in the decision-making process, which may reduce the overall efficiency and lead to global nonoptimality. This study incorporates the cost to the shipping companies at the main lines, ports, and feeder services, as well as the external costs to shippers and ports in a hub-and-spoke network, and determines the best ship size and the number of weekly services to minimize the overall costs. The external cost to the shippers in the feeder ports is assumed to be proportional to the feeder cost, and a sensitivity analysis is provided. The maximum container ship size is estimated according to different levels of freight demand. A numerical analysis shows that the optimal size should be smaller than the current biggest container ships in service.     

Next generation mega container ports: implications of traffic composition on sea space demand

ABSTRACT

Demand for sea space brought about by increasing container-shipping traffic has important implications on how this space is managed and used. This is particularly important given the long-term nature, high-asset specificity, high- opportunity cost of investment, and significant economic impact of container port activity on a locality. The challenge is especially pressing for ports, which are facing constraints in seaside capacity where container traffic also has to co-exist with the needs of other types of ship traffic. This challenge is likely be multiplied for next generation container ports, which are expected to handle even larger traffic volumes. These ports are also likely to face competing sea space demands from other economic and social activities especially when they are concurrently major confluences of trade, logistics, and urban populations. This is the first research to investigate in detail the impact and importance of investigating sea space requirements from the perspective of cargo traffic composition and ship capacity. Results show that transshipment containers can generate much higher demand for sea space due to the higher volume of shipping capacity that accompanies such traffic. Sustainability issues and managerial and policy implications pertaining to the development of next generation container ports are provided.     

沿海集装箱港区港内锚地面积确定方法

设置港内锚地,是沿海集装箱港区缓解航道拥堵,提高港口服务水平的有效途径之一。为完善港内锚地面积确定方法的理论研究,基于计算机仿真技术,建立设置港内锚地的沿海集装箱港区船舶航行作业系统仿真模型,研究计算期内可能同时占用港内锚地的船舶数量及船型组合;计算不同锚泊方式下所需的港内锚地最大面积。仿真结果与分析结论为沿海集装箱港区港内锚地的规划建设及改造扩建提供参考。     

A break-even model for evaluating the cost of container ships waiting times and berth unproductive times in automated quayside operations

The planning, design and development of a container terminal with optimum size and capacity and with a minimum capital cost is fundamentally dependent upon the loading and discharging operations at the quayside. The quayside function of container terminals is dependent basically on the number of berths available to service the incoming container ships. The objective of the container terminals dealing and admitting the ongoing ship calls is to provide immediate berth and loading and discharging services to the container ships with a minimum costly waiting time and a maximum efficiency. Previously terminal planners used to build extra berths to provide service. During the last two decades the terminal operators have adopted automation technologies in loading and discharging operation of the container ships as an alternative to designing extra berths. Ship owners naturally expect least waiting times for their container ships. On the other hand, it is also natural for port operators in a container terminal with costly facilities to see a high berth occupancy and productivity at the quayside. This study uses queuing theory to find a break-even point as a way of evaluating the cost of container ship waiting times and the cost of berth unproductive service times for container terminals aiming to automate their quayside operation. The analysis illustrates that automation devices installed on conventional Quayside Cranes (QSCs) significantly reduce the turnaround time of the container ships calling at the ports. It argues, however, that there should be a balance between the cost of berth unproductive service times and the cost of vessel waiting times. The study introduces a break-even point to be considered as a benchmark for calculating such a balance. The analysis in this study can be used as a decision tool for the operators of container terminals in the medium to small ports to appraise the feasibility of an investment in automation or expansion of the quayside facilities.     

Modelling and optimisation of online container stacking with operational constraints

Container transportation plays a critical role in the global shipping network and container terminals need to improve their operations to increase efficiency. Storage yard of a container terminal is a temporary area where the containers stay until they are shipped to their next destination. We concentrate on increasing the efficiency of the storage yard by developing online stacking policies for each incoming container. An unproductive move of a container, performed to reach another container stored underneath, is called reshuffling. The objective in container stacking problem is to minimise the number of reshuffles, thereby increasing the efficiency of terminal operations. Additional weight-related operational constraints bring additional complexity to the online stacking decisions. We propose a mathematical model for the optimal online assignment of an incoming export, transit, import or empty container. We also propose an optimal online stacking policy and compare it with a random policy through simulation. Additionally, lower bounds for the performance measures are obtained through simulation by relaxing the operational constraints of the problem in a third stacking policy. We present and discuss the computational results in terms of four main performance measures.     

Weekly container delivery patterns in liner shipping planning models

This paper addresses a fundamental question related to nearly all container liner shipping planning models: whether the implicit assumption of identical container delivery pattern every week is valid in a situation of identical shipping services and identical cargo demand every week. We prove that when the number of containers transported from one port to the next is formulated as a continuous variable, the resulting mathematical model with an identical container delivery pattern is equivalent to the model with general container delivery patterns which can be different in different weeks. When the number of containers transported is formulated as an integer variable, the model with an identical container delivery pattern is not equivalent to the model with general container delivery patterns. However, the difference between the optimal objective values of the two models is negligible for practical applications. In sum, little, if not nothing, is lost by assuming an identical container delivery pattern in liner shipping planning models.     

Design and implementation of a visual monitoring system to ensure safety in the water surrounding a container vessel

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.     

Fuzzy empty containers excess estimation as an economic indicator—the case of the north Adriatic port system

Today, approximately 90% of the world’s cargo is moved by ships and almost all general cargoes are transported in containers. Worldwide container traffic has increased over the last 20 years by 7% annually, and containerization has begun to seriously impact global trade patterns. As a result, container terminals have become very important nodes in the world’s supply chain. In this article, we have highlighted the link between the total and empty container traffic and the global economy. By way of example, we have analysed the empty container traffic in north Adriatic ports in the years before and during the global economic crisis and in a period of stability after the major economic slump. We used a fuzzy multicriteria algorithm to find out how the global crisis, which has affected ports, influences the number of excess empty containers at the terminals. We show that these factors, in particular the change of the global financial and economic situation, have different repercussions to the ports of the north Adriatic: less serious effects upon the ports that are well connected locally and substantial consequences for the ports that are well connected globally.     

Forecasting container throughput based on wavelet transforms within a decomposition-ensemble methodology: a case study of China

To improve predictive accuracy, new hybrid models are proposed for container throughput forecasting based on wavelet transforms and data characteristic analysis (DCA) within a decomposition-ensemble methodology. Because of the complexity and nonlinearity of the time series of container throughputs at ports, the methodology decomposes the original time series into several components, which are rather simpler sub-sequences. Consequently, difficult forecasting tasks are simplified into a number of relatively easier subtasks. In this way, the proposed hybrid models can improve the accuracy of forecasting significantly. In the methodology, four main steps are involved: data decomposition, component reconstruction based on the DCA, individual prediction for each reconstructed component, and ensemble prediction as the final output. An empirical analysis was conducted for illustration and verification purposes by using time series of container throughputs at three main ports in Bohai Rim, China. The results suggest that the proposed hybrid models are able to forecast better than do other benchmark models. Forecasting may facilitate effective real-time decision making for strategic management and policy drafting. Predictions of container throughput can help port managers make tactical and operational decisions, such as operations planning in ports, the scheduling of port equipment, and route optimization.     

Reposition of empty containers of different life stages integrated with liner shipping network design

ABSTRACT

This paper integrates empty container reposition with container shipping network design considering the container life stages. A mixed-integer linear programming model is built to determine the liner shipping network, the initial launch ports of new containers, the ports for scrapping obsolete containers, the empty container reposition scheme and the containers of different life stages being used for a specific voyage. A case study is done by taking liner shipping among China, Japan and South Korea, Southeast Asia, Europe and the US as an example. The results show that over 93% of new containers are put into use in China while 63% of old containers are scrapped in Europe or the US, and 73% of containers used for packing cargoes from China to the US are those at the Decline Stage or the Exit Stage.     

Multi-period liner ship fleet planning with dependent uncertain container shipment demand

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.     

船舶大型化对航运和港口的影响

目前订造中的7 500 TEU以上的船舶有100多艘。其中许多船舶将于2007年下水,投入亚洲-欧洲和跨太平洋贸易航线的营运。“超级集装箱船”(VLCS)正在坚定地从概念走向现实。超过8 000TEU的船舶的投入使用,对班轮公司、航运贸易和集装箱码头提出了新的挑战。班轮公司应该通过削减一组环线中的船舶数目、改变挂靠港和重新组织航运网络的规划途径来应对挑战。先进枢纽港应该通过开发新概念的港口装卸系统和新概念码头来应对挑战。超大型集装箱船舶挂靠的港口不能仅仅是简单的枢纽港,同时必须成为物流平台。     

国际集装箱船舶大型化对世界集装箱港口发展的影响

分析国际集装箱船大型化过程中和发展趋势以及大型化对集装箱港口发展的影响，指出我国的集装箱港口发展应适应需要，重点建设国际航运中心集装箱枢纽港，合理布局，形成完善的干线网络。     

A slot reallocation model for containership schedule adjustment

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.