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.     

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.     

Strategic fleet size planning for maritime refrigerated containers

In the present economic climate, it is often the case that profits can only be improved, or for that matter maintained, by improving efficiency and cutting costs. This is particularly notorious in the shipping business, where it has been seen that the competition is getting tougher among carriers, thus alliances and partnerships are resulting for cost effective services in recent years. In this scenario, effective planning methods are important not only for strategic but also operating tasks, covering their entire transportation systems. Container fleet size planning is an important part of the strategy of any shipping line. This paper addresses the problem of fleet size planning for refrigerated containers, to achieve cost-effective services in a competitive maritime shipping market. An analytical model is first discussed to determine the optimal size of an own dry container fleet. Then, this is extended for an own refrigerated container fleet, which is the case when an extremely unbalanced trade represents one of the major investment decisions to be taken by liner operators. Next, a simulation model is developed for fleet sizing in a more practical situation and, by using this, various scenarios are analysed to determine the most convenient composition of refrigerated fleet between own and leased containers for the transpacific cargo trade.     

Empty container repositioning in liner shipping1

The efficient and effective management of empty containers is an important problem in the shipping industry. Not only does it have an economic effect, but it also has an environmental and sustainability impact, since the reduction of empty container movements will reduce fuel consumption and reduce congestion and emissions. The purposes of this paper are: to identify critical factors that affect empty container movements; to quantify the scale of empty container repositioning in major shipping routes; and to evaluate and contrast different strategies that shipping lines, and container operators, could adopt to reduce their empty container repositioning costs. The critical factors that affect empty container repositioning are identified through a review of the literature and observations of industrial practice. Taking three major routes (Trans-Pacific, Trans-Atlantic, Europe–Asia) as examples, with the assumption that trade demands could be balanced among the whole network regardless the identities of individual shipping lines, the most optimistic estimation of empty container movements can be calculated. This quantifies the scale of the empty repositioning problem. Depending on whether shipping lines are coordinating the container flows over different routes and whether they are willing to share container fleets, four strategies for empty container repositioning are presented. Mathematical programming is then applied to evaluate and contrast the performance of these strategies in three major routes.     

A reactive container rerouting model for container flow recovery in a hub-and-spoke liner shipping network

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.     

Cost analysis of bulk cargo containerization

ABSTRACT

Bulk cargo containerization (BCC) involves changes in the transportation mode of container shipping for cargo that uses bulk carriers without packing. This topic has recently attracted considerable attention as an alternative transportation method for container cargo. BCC is advantageous because it can address imbalances in the amount of cargo conveyed between the main and back hauls, thereby improving efficiency. A previous survey among companies involved in cargo shipping revealed that in addition to ocean freight, vanning and devanning, and customs clearance costs, consignees’ decisions were the key factor in selecting transport modes. The present study aims to clarify the cost competitiveness of container shipping and identify cost reductions that may increase the use of BCC. To quantitatively check the results of the survey employed in this study, we constructed a model based on consignees’ and container shipping companies’ costs to determine the choice of transport mode for back-haul trade, then examined the incentives for consignees and shipping companies. We found that BCC can be realized by cost reduction on the part of the consignee and profit improvement on the part of the container shipping company for some routes and goods. Although reducing the freight rate would effectively promote BCC, reducing other costs would not have the same effect.     

Safe manning of merchant ships: an approach and computer tool

In the shipping industry, staffing expenses have become a vital competition parameter. In this paper, an approach and a software tool are presented to support decisions on the staffing of merchant ships. The tool is implemented in the form of a Web user interface that makes use of discrete-event simulation and allows estimation of the workload and of whether different scenarios are successfully performed taking account of the number of crewmembers, watch schedules, distribution of competencies, and others. The software library ‘SimManning’ at the core of the project is provided as open source. The tool is conceived as a support for the maritime authorities, certifying bodies and shipping companies to assess whether a ship is safely manned.     

从供应链管理看现代物流对我国航运业的影响

在海洋运输的基础上,全面介入物流服务,积极配合货主对运输服务更高层次的要求,以货主为中心全面提高门到门运输的服务水平,将给航运企业自身带来多方面的竞争优势。事实表明,从海洋运输向综合物流服务转变,已经成为国际航运企业发展的大方向。本文介绍了现代物流的供应链管理、“双赢”及“多赢”战略,以客户为中心等理念在航运业中的应用情况;结合大量的例子,从供应链管理角度分析我国航运存在的问题,并探讨解决问题的措施。     

Optimal management of human resources in transhipment container ports

Human resources allocation plays a key role in transhipment maritime container terminals to achieve high levels of productivity and provide high quality services to shipping companies. The deep interest of container terminals in this issue can be supported by optimization methods. In this work, an optimization model is proposed to determine the optimal daily allocation of crane operators and trailer drivers. Different requirements are taken into account for permanent staff, external workers and personnel shortfall. Since workforce undermanning is a crucial factor for both shipping companies and container terminals, we aim to show that personnel shortfalls and operation delays can be significantly reduced if the model encompasses a longer-than-1-day planning horizon in a rolling horizon fashion.     

集装箱船舶大型化对中国班轮运输的影响

通过竞争情报分析提供了各班轮公司未来船队结构和运力的变化趋势,由此观察到各班轮公司为了降低自身的营运成本,在最近几年大量订购超巴拿马型甚至更大型的集装箱船舶参与运输,但是却不能达到其预期的规模效应。原因就在于相当一部分成本随着船型的增大而线性增加,规模不经济。我们探讨了中国的班轮运输市场的几个重要特点:中外贸易的不平衡导致了货源的不平衡;未来贸易结构的调整会影响航线的布局和调派;贸易上的不稳定因素使班轮公司遇到外在的风险。这些特点会深远地影响集装箱船舶大型化的经济受益,相反的,集装箱船舶大型化的趋势也会加剧这些负面的影响,危及整个班轮运输市场。     

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.     

环日本海地区的航线优化研究

随着环日本海地区贸易往来的频繁,优化该地区航运网络结构,提升海运通达性,成为推动该地区经济发展的重要手段.因此,提出一个以航运企业利润最大为目标的航线网络优化模型.该模型综合考虑航线、船型与需求间的关系,以船舶的载重量为约束,优化航运企业的资源配置,设计航线及选择适宜船型.利用实际数据对该模型进行检验,结果显示,优化的航线网络以及确定船型在不同经济条件下有所差别,可为环日本海航线的开辟与运营提供借鉴.     

Application of El Farol model for managing marine terminal gate congestion

Truck queuing at marine terminal gates has long been recognized as a source of emissions problem due to the large number of trucks idling. For this reason, there is a great deal of interest among the different stakeholders to lessen the severity of the problem. An approach being experimented by some terminals to reduce truck queuing at the terminal is to provide live views of their gates via webcams. An assumption made by the terminals in this method is that truck dispatchers and drivers will make rational decisions regarding their departure times such that there will be less fluctuations in truck arrivals at the terminal based on the live information. However, it is clear that if dispatchers send trucks to the terminal whenever the truck queues are short and not send trucks when the truck queues are long, it could lead to a perpetual whip lash effect. This study explores the predictive strategies that need to be made by the various dispatchers to achieve the desired effects (i.e. steady arrival of trucks and hence less queuing at the seaport terminal gates). This problem is studied with the use of an agent-based simulation model and the solution to the well known El Farol Bar problem. Results demonstrate that truck depots can manage (without any collaboration with one another) to minimize congestion at seaport terminal gates by using the provided real-time gate congestion information and some simple logics for estimating the expected truck wait time.     

集卡调度方式对集装箱港区碳排放的影响

集卡已成为集装箱港区内的主要碳排放源,尤其两艘大型集装箱船舶同时作业时,港区内集卡碳排放问题严重。针对该情况下集卡调度模式的特征,基于智能体仿真技术构建集装箱码头生产作业微观仿真模型,定量分析传统先卸后装、双船一装一卸、同贝同步装卸工艺下集卡调度方式与集卡配置数量对船舶在港时间、集卡碳排放量的影响。实例表明,采用同贝同步装卸作业方案可保证装卸效率,并有效减少集卡碳排放,而集卡配置数量只对集卡怠速行驶产生的碳排产生影响。     

A combined tramp ship routing,fleet deployment,and network design problem

In this paper, a tramp ship routing model of fleet deployment in a hub-and-spoke network is presented. This model simultaneously determines the selection of hubs, the assignment of spokes to hubs, the deployment of feeder-containerships as well as containership routing between spokes and spokes, hubs and spokes, and hubs and hubs. Even though some parts have been studied, this complex combination of shipping problems has never been addressed. Because the problem is NP-hard, a genetic algorithm (GA) with local search is proposed. In the algorithm, a cut-off procedure is applied to fleet deployment in a sub-route strategy. A number of randomly generated problem instances are solved by both a mathematical program and the GA with local search. A simple but realistic heuristic algorithm is also developed. Both the GA with local search and the heuristic algorithm are used to solve a number of real case instances. A comparison of the results shows the efficiency of the GA with local search. The developed model can be used as a route-decision support tool for shipping companies that provide long-haul shipping services in a hub-and-spoke network.     

新型集装箱汽车衡称重技术与误差分析研究

为了对一辆集卡装载的2个20英尺集装箱进行分别称重，设计了新的汽车衡结构，推导出计算公式并进行实验验证，得到了一种可以保证作业安全且能为港口和货主接受的集装箱汽车衡称重方法。     

The impact of low sulphur fuel requirements in shipping on the competitiveness of roro shipping in Northern Europe

Annex VI of the MARPOL Convention aims for a reduction in sulphur oxide emissions from ships. The limits applicable at sea in Emission Control Areas (ECAs) were reduced from 1.5% to 1% in 2010 and are planned to be further reduced to 0.1%, effective from 1 January 2015. This paper analyses the impact of the International Maritime Organization’s Tier II/III standards introduced by Annex VI amendments adopted in October 2008 on costs and prices of roro (roll on/roll off) traffic in the ECAs in North Europe and on the competitiveness of roro shipping in the ECAs compared to trucking. We demonstrate that the new Annex VI agreement may be quite costly for the participants in the shipping industry and will result in higher freight rates. Based on a detailed price analysis on modal competition between the roro/truck option and the ‘truck only’ option on thirty origin–destination routes linked to the ECAs, we conclude that the use of low sulphur fuel is expected to increase the transport prices particularly on the origin–destination relations with a medium or long short sea section. The paper also presents the results of a survey among leading short sea operators in the ECAs in view of providing more insight on expected modal shifts and price elasticity in the short sea market.     

The relative efficiency and financial risk assessment of shipping companies

Since shipping companies are highly competitive, we ask whether financial risk assessment tools impact company performance and, therefore competitiveness and efficiency. Stochastic Frontier Analysis (SFA) is used in the evaluation. Based on distinct features of the risk-return relationship, three cargo segments in the shipping industry are studied—dry bulk, liquid bulk, and containerized cargo. The influence of the risk assessment indicators on market and operational efficiency is subsequently determined using a panel regression to determine whether different asset allocation and risk management techniques improve the performance of shipping companies. In this analysis, 79 international shipping companies listed in Bloomberg Shipping Indices are included in the data collected from Thomson One for the period of 2001–2010. Efficiency estimation from the SFA shows that containerized cargo firms have better performance in both market and operating efficiencies. Operating efficiency performance is achieved by lowering liquidity. Market efficiency is improved by well-managed leverage level.     

实物期权在航运企业船舶投资决策中的应用

航运业是一个具有特殊风险的行业,然而传统的船舶投资决策却总是忽略不确定性对投资价值的影响。将实物期权运用到航运企业船舶投资决策中,运用布莱克-舒尔斯的期权定价公式,得出含有实物期权的投资价值和一般的投资价值,定量地分析了不确定性对投资价值的影响,使船舶投资价值与决策相一致,最终使航运企业获得最大的投资收益。     

Analyzing ship investment behaviour in liner shipping

This study analyzes capacity expansion and ship choice decisions. Theoretically, we derive the probability of capacity expansion as a function of market and company attributes and characterize the impacts of these factors on expansion decisions. Empirically, we analyze ship investment and ship choice behaviour using binary choice and nested logit models based on ship investment data from major liner shipping companies over the period 1999 to 2009. Most expansion decisions are found to be market-driven, and large companies expand to maintain their market shares. In terms of ship selection, statistical results support the assumption that shipping companies decide on a new order or second-hand purchase before considering the ship size. Also, new orders are preferable to second-hand purchases. For new orders, the preference increases with ship size, and decreases with shipbuilding length and demand growth rate. For all ship types, the preference increases with a high and stable time-charter rate. For second-hand ships, handysize is the most preferable size. The substitution of new orders and second-hand purchases is possible, but not symmetrical.