Short-term liner shipping bunker procurement with swap contracts

The bunker price fluctuations in recent years have severely threatened the stability of liner shipping companies’ operations. As an efficient countermeasure, the swap contract is widely adopted throughout the liner shipping industry to hedge the procurement risk resulting from the bunker price fluctuation. This paper looks at the short-term liner shipping bunker procurement problem with swap contracts (BPPSC), aiming to optimally plan the amount of bunker purchased from the spot market and the amount hedged by the swap contract for several months ahead. This BPPSC is first formulated as a bunker procurement cost mean-variance minimization (MVM) model, and is subsequently solved using a tangible two-step approach developed in this study. In the first step, the movements of the swap contract price and the spot market price of the bunker are described using a calibrated multivariate generalized autoregressive conditional heteroskedasticity (mGARCH) time series model. In the second step, the MVM model is approximated and solved by a price scenario tree constructed from the mGARCH time series model. A numerical example shows that the risk hedging strategy obtained can simultaneously control the bunker procurement cost as well as the procurement risk from price fluctuations. This article is a revised and expanded version of the abridged eight-page paper entitled ‘Optimal hedging for liner bunker procurement’ presented at ‘2015 International Conference on Logistics and Maritime Systems (LOGMS 2015)’, Hong Kong, 27–29 August 2015.     

The coopetition game in international liner shipping

In maritime freight transportation, carriers build collaborative relationships with other carriers while competing with each other to optimize their own profits. In such a scenario, a game of coopetition is formed. We formulate a nonlinear mixed-integer problem to determine the optimal levels of coopetition for a single company and embed the resulting problem into a general game theoretic framework. A diagonalization algorithm that incorporates an ascent direction search technique is developed to effectively evaluate the game. The numerical results show that carriers choose similar coopetition levels to maximize their profits, and the coopetition game can reach equilibrium under general conditions.     

Effects of job demands and social interactions on fatigue in short sea cargo shipping

Although fatigue is considered an important problem in shipping, little is known about potential mitigating factors or resources for coping. Adopting a Job Demands–Resources framework, this article examines the effects of both job demands (stressors) and resources on fatigue, focusing on social interactions on board as a potential source of social support. Using an incomplete repeated-measures design, the study combined information from documents with surveys on seven cargo ships. Findings indicated that fatigue levels were highest for those working on deck and for individuals at higher hierarchical levels. Higher numbers of port calls (and to some extent lower numbers of days at sea) also increased fatigue levels. By contrast, night watches and the number of days in port had no effect on fatigue. Supportive social interactions reduced fatigue (main effect), but their effect was weaker when the number of port calls increased (interaction effect). All main effects were mediated by individuals’ perceptions of work pressure. Taken together, findings highlight the importance of considering social interactions on board to advance our understanding of stressors and strain in seafaring.     

Internalization of port congestion: strategic effect behind shipping line delays and implications for terminal charges and investment

This paper develops a theoretical model to analyze the congestion internalization of the shipping lines, taking into account the ‘knock on’ effect (i.e. the congestion delay passed on from one port-of-call to the next port-of-call). We find that with the presence of the knock-on effect, liners will operate less in terminals, and an increase of a liner’s operation in one terminal will decrease its operation in the other. If the liners are involved in a Stackelberg competition, whether they operate more or less in a terminal under the knock-on effect depends on the comparison between the marginal congestion costs of terminals. Furthermore, we find that the coordinated profit-maximizing terminal charges are higher than both the socially optimal terminal charges and the independent profit-maximizing terminal charges. When the knock-on effect is small, the independent profit-maximizing terminal charges are set at higher levels than the socially optimal terminal charges; but when the knock-on effect is sufficiently large, this relationship may reverse. Besides, the capacity investment rules are the same for welfare-maximizing terminal operator and coordinated profit-maximizing terminal operator, while independent profit-maximizing terminal operators invest less in capacity. The larger the knock-on effect, the larger this discrepancy.     

Norwegian port connectivity and its policy implications

The importance of a seaport depends on how well it is connected in a transportation network. A port’s connectivity is therefore one of the key issues in determining its competitiveness and developments in regions and countries. We construct a port connectivity index for major Norwegian ports based on a unique dataset derived from the automated identification system (AIS) for multiple vessel types over a 7-year period. Port connectivity is evaluated empirically by the number of unique vessel visits, vessel sizes, and cargo sizes. The research has implications for port authorities and policy makers in the areas of port planning, infrastructure investment, short sea shipping promotion, and environmental policies. The contributions of this research are twofold. First, the methodology linking the AIS vessel-tracking system with port connectivity is a pioneering empirical application of maritime big data. Second, the port connectivity index is constructed for multiple vessel types and regional port groups, which is an improvement from the current literature where conceptual measures are constructed based on hypothetical and usually too simple optimization rules. The methodology can be easily expanded to other regions in the world.     

上海内河跨航道桥梁防撞设施分析

针对上海内河跨航道桥梁水上防撞设施,对桥梁防撞体系、船撞力计算方法进行论述,结合内河跨航道桥梁自身特点和最新防撞理念,对适合内河跨航道桥梁的防撞方案和设施进行分析。结果表明:适合上海内河跨航道桥梁水上防撞的防撞设施主要有固定或浮式防撞装置和桩基防撞墩两种类型,若这两种类型防撞设施不具有施工条件,一般采用小规格缓冲材料对桥墩进行防护;对于与黄浦江直接连通的支流桥梁,除小规格缓冲材料,一般采用防护桩。     

关于我国内河船舶污染强制责任 保险限额的研究Ⅰ ——国内外船舶污染强制保险责任限额的设置研究

本文是财政部基本科研业务费专项项目“港口近岸生态环境损害评价方法及生态修复技术研究”的研究成果。为建立适合我国国情的内河船舶污染强制责任保险限额的制定方法,文章通过分析国内外船舶污染责任保险限额设定内容、设定方式和设定依据,明确其设定思路并分析其优缺点,进一步确定我国内河船舶污染责任保险限额的的法律依据,比较责任限额的科学设置方法。在“限额设置区间、区间递进方式、限额变动、起始吨位、使用货币、责任限额的确定方式、对责任限制的免除条件、法律基础”等方面进行了理论创新,提出详细的可操作性设置建议。     

多功能智能测流航标的研制与应用

专门研制的多功能智能测流浮标,运用标准横流标(浮标)为载体,配置集成专用多普勒流速仪、超声波水位器、风速风向传感器、卫星定位器、数据信息智能处理器等设备与专用管理系统,有效解决内河航道重要河段、河口的水位、水深、流速、流向、能见度、风速、风向等与船舶航行有关的实时动态要素的智能采集与传输等技术问题,实现内河航道要素船岸智能感知,引导船舶安全航行。     

上海内河货运量的组合预测

内河航运是综合交通运输系统中不可缺少的运输方式,存在着很大的潜在优势.定量地把握未来内河运输的发展趋势,具有重大的现实意义.通过利用时间序列模型、logistic曲线与自回归模型等,对2010-2015年的上海内河货运量进行预测.在此基础上,对不同模型赋予不同的权重,建立了组合预测模型.研究表明:未来上海内河货运量将持续稳定地增长.为提高预测的精度,有必要综合地使用多个预测方法.     

基于价值链的中海集运公司风险管理

现代海运业具有"高投资、高风险、高收益"的特点.由于风险众多而分散,传统的企业风险管理模式已难以满足现代航运企业对于风险管理的需求.从系统和集成的角度出发,提出了基于Hines价值链的航运企业风险管理模式,将航运企业面临的风险分为企业内部风险、企业间风险、价值链外部风险等3个层次;针对不同层次的风险宜采取不同的风险处理策略,并特别论述了上述3层次风险之间的关联性.作为案例,对中海集运公司的风险管理实践进行了剖析.结论表明,我国航运企业在企业内部风险管理方面已积累了丰富的经验,并开始重视通过企业间合作来削弱企业间风险的影响,但在价值链外部风险上尚乏举措,在风险管理文化的构建上亦有待深化.