A comparison of different container sorting systems in modern rail-rail transshipment yards

Rail-rail transshipment yards act as central hub nodes within a railway network and enable a rapid consolidation of containers between different freight trains. To avoid an excessive movement of gantry cranes when transferring a container from one train to another, modern yards apply sorting systems where shuttle cars move containers horizontally along the spread of the yard. This paper compares four elementary sorting systems. Specifically, we compare rubber-tired and rail-mounted shuttles and differentiate whether a pure shuttle system or a lift & shuttle system is applied. In pure shuttle systems, a shuttle receives a container from a crane and transports it towards the destination crane, where it serves as a storage device until being unloaded. A lift & shuttle system applies shuttles with an integrated lifting platform, so that they are able to autonomously store and receive containers from a separate storage rack. Both alternatives exist in rubber-tired and rail-mounted versions. As the shuttles are the main driver of the investment costs, we compare the required fleet size for timely supplying given gantry crane schedules within all four systems. For this purpose, we derive suited scheduling procedures. This way, decision support for yard managers having to identify a suited sorting system and to layout a new terminal is provided.     

Estimation of directional wave spectra and hull structural responses based on measured hull data on 14,000 TEU large container ships

To ensure hull structural strength of container ships in association with their increase in size, it is very important to grasp the hull stress histories all over the hull structure in actual sea state. However, ordinary hull stress monitoring systems are insufficient for this purpose because of the small number of stress sensors actually practicable. Therefore, in this paper, we discuss an approach to reproduce the hull stress responses which are not measured based on the estimated wave spectrum from the limited measurement data. To achieve this, we introduce a new model to estimate directional wave spectra based on measured ship stress responses and ship response functions, and further we estimate other ship responses using the model. To model an arbitrarily shaped directional wave distribution, the 360° direction is discretized into 36 directions of 10-degree intervals instead of using a directional distribution function, and in each direction, the wave spectrum is represented using the Ochi (3P) spectrum with three parameters (average wave period, significant wave height, and kurtosis). The authors discuss the evaluation results based on two stress response combinations, and a comparison is made between the sea state estimates made by the proposed method and the ocean wave hindcast database (JWA). Furthermore, by comparing the significant values and the spectra of the measured response of the ship with the estimated response based on both the estimated sea state by the proposed method and the hindcast sea state, the accuracies of the proposed method and the hindcast method are discussed in terms of ship stress estimation at non-instrumented locations.     

Segment-based alteration for container liner shipping network design

Container liner shipping companies only partially alter their shipping networks to cope with the changing demand, rather than entirely redesign and change the network. In view of the practice, this paper proposes an optimal container liner shipping network alteration problem based on an interesting idea of segment, which is a sequence of legs from a head port to a tail port that are visited by the same type of ship more than once in the existing shipping network. In segment-based network alteration, the segments are intact and each port is visited by the same type of ship and from the same previous ports. As a result, the designed network needs minimum modification before implementation. A mixed-integer linear programming model with a polynomial number of variables is developed for the proposed segmented-based liner shipping network alternation problem. The developed model is applied to an Asia–Europe–Oceania liner shipping network with a total of 46 ports and 11 ship routes. Results demonstrate that the problem could be solved efficiently and the optimized network reduces the total cost of the initial network considerably.     

An empirical study of the impacts of operating and market conditions on container-port efficiency and benchmarking

Despite the growing amount of research on container-port efficiency and benchmarking, the literature on the subject is yet to provide stable and consistent results across researchers and in relation to dynamic operating and market conditions. In this paper, we formulate a number of operational hypotheses to test the sensitivity of benchmarking results to port market and operating conditions namely production scale, cargo mix, transhipment ratio, operating configurations, and working procedures. A series of data envelopment analysis (DEA) models are used to measure the operational efficiency of 420 container terminal decision-making units from 2004 till 2010. The results show that variations in operating conditions highly impact terminal efficiency and that future work on container-port performance and benchmarking should take into account the structure and mechanisms underpinning the operations of container ports and terminals.     

集装箱船舶大型化对上海港发展的影响和机遇

在集装箱航运市场中,由于超大型集装箱船优良的经济性能及全球集装箱航运结构的重组,并且在全球国际集装箱运输呈增长的趋势背景下,大批超大型集装箱船投入运营,对上海港的运营和发展形成一定的影响,但同时也给上海港的发展带来了机遇。上海港要应对国际航运市场的这种变化,就必须采取相应的策略。随着长三角经济圈的发展和洋山深水港一期、二期工程的完工,进一步巩固了上海港的国际集装箱枢纽港地位,上海港应抓住新的发展机遇,为上海早日建成国际航运中心奠定更加坚实的基础。     

基于WITNESS的集装箱码头物流系统仿真及优化

集装箱码头作业区物流作业优化的结果可以大幅提高工作效率,在不增加新设备投入的情况下有效改善港口工作状况。利用W ITNESS仿真软件进行物流作业仿真是一种投入少,见效快的方法。以天津港某集装箱码头公司实际情况建立仿真模型,根据模拟运行结果反应进行物流作业优化的途径。     

浅谈集装箱装运危险货物瞒报谎报行为的查处方法

本文通过对危险货物瞒报谎报行为形成原因的研究,提出查处该行为的基本方法,以利于海事部门找到相应处理对策。     

结点站吸引范围内集装箱运输组织方式研究

各集装箱办理站产生的集装箱流向其邻近的结点站输送,可能产生的运输方案有三个。方案一:用普通集装箱列车挂运直接进入结点站作业;方案二:用一般摘挂列车输送,在编组站改编后用小运转列车向结点站输送;方案三:用一般摘挂列车输送直接进入结点站改编。分析不同运输方案的作业过程,将运输过程产生的箱小时、车小时消耗按作业性质分解并分别计算。比较不同方案的总的箱小时、车小时消耗可知,方案一为消耗最少的运输方案。同时分析各运输方案实施可行性,方案一对区间能力占用较大,方案二较为有利。由此得出结论:方案一可作为集装箱运输发展的方向,方案二是目前状况下较为有利的运输方案。     

集装箱港口竞合战略研究

世界集装箱港口呈现区域化发展和与竞争者合作的趋势。重点分析了现代集装箱港口业的各方压力和竞争态势;以香港和深圳港各集装箱码头为例,对港口间的"为了竞争而合作"的"竞合"战略的优势和组织方式进行了详细的研究。     

港口枢纽集装箱运输的协调评价

港口枢纽集装箱运输的协调程度对该系统的发展有着很大的促进或制约作用。通过建立港口枢纽集装箱运输的协调评价指标体系和协调评价模型,找出影响系统协调的主要因素和薄弱环节,从而对港口管理部门采取有力措施进行经营决策以争取系统的最大利益,以及制定港口发展规划具有一定的指导意义。