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1.
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.  相似文献   

2.
The economic crisis in the years between 2008 and 2010 has demonstrated the necessity for substantial adjustments on behalf of container lines. Capacities were shifted quickly to emerging and less affected markets allowing a faster recovery of globally organized companies. This paper illustrates the dynamics in the container shipping market. Alongside the main characteristics of the Top 20 ocean shipping companies, liner services are described. These services are classified by geographic coverage and vessel deployment. In addition, this paper provides a better understanding of the collaboration among service providers. Starting from a general framework of co-operative liner services, in-depth analyses of the global alliances in liner shipping are obtained. These formations - Grand Alliance, New World Alliance and CKYH Alliance - are compared with alternative forms of collaboration in the liner shipping industry. The analysis of alliance announcements which are related to operational and strategic changes indicates that the “global alliances” cannot be regarded as closed corporate-like entities. In effect, service agreements are not only negotiated with the focal members of the specific alliance. Instead, every service is arranged individually and under specific conditions. By understanding the dynamics within alliances, we are able to develop an assessment relating to the stability of collaborations. Ultimately, these insights direct us to several paths for future research.  相似文献   

3.
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   

4.
The Malacca Strait, the Suez Canal and the Panama Canal play an important role in the global container shipping. To study the impact of main channel interruption on the container shipping, we analysed statistical data on all routes operated by the top 100 global container liner companies and constructed a network model. We selected four topological metrics to measure the network’s connectivity and used the network weekly total shipping capacity and average shortest shipping time to measure the network’s transportation capacity and transportation time. The interruption of the main channel is simulated, and the changes in the metrics are analysed. The results indicated that the network’s vulnerability is sensitive to main channel interruption. If the Malacca Strait is interrupted, the network’s prosperity degree fall by almost half and the network’s transportation time increase by more than a quarter if the Suez Canal is interrupted. In addition, East Asian and European container liner shipping have more than 50% dependence on the Malacca Strait and the Suez Canal. Moreover, the container transport time between ports in East Asia, Europe, and North America and the rest of the world increases by an average of 4–9 days in the main channel interruption.  相似文献   

5.
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.  相似文献   

6.
《世界海运》2010,33(1):18-19
<正>一直以来,我国航运运价主要由市场主导,经营者根据市场需求自行调节。然而在金融海啸席卷全球之时,这种完全市场化的运价调整却显现出弊端——需求大幅下滑,调低价格成为航运企业开展恶性竞争的唯一手段。新情况的出现给有关部门管理者提供了  相似文献   

7.
8.
In this paper, we empirically test the relationship between the delay of containerships and the scheduled operations in a terminal, based on a dataset containing information on 352 containership arrivals during a 9-month period at seven terminals of three North American ports. We find that a vessel is less likely to be delayed when there are more operations scheduled shortly (up to 3 days) after the vessel’s berthing window in the terminal. Moreover, we also find that the more containers a vessel needs to unload in the terminal, the less likely that it would be delayed. Both findings support the hypothesis that liners strategically balance the trade-off between delay cost and schedule recovery cost.  相似文献   

9.
10.
下半年,集装箱班轮运输虽有望在复苏第一波的高位运行,但快速增长的旺盛势头难以持续,前高后低的走势或成定局。  相似文献   

11.
Liner shipping is normally viewed as being oligopolistic in nature with firms competing on the basis of service offered. Since shipping services are easily copied by competitors, if shipping firms want to gain a competitive advantage, it is essential to identify the competitors' strategies. This paper uses the analytical concepts of strategic groups theory to explore the strategic differences in the Taiwanese (the Republic of China, ROC) shipping industry. Cluster analysis is used to classify shipping companies, shipping agencies and ocean freight forwarders into four strategic groups on the basis of the key strategic factors obtained from the factor analysis. The results of multivariate analysis of variance (MANOVA), analysis of variance (ANOVA) and the Scheffe test showed that strategies among the strategic groups are significantly different.  相似文献   

12.
首先分析不同航线选择算法的优缺点,然后对本文所采用的A~*算法进行阐述。将集装箱船的航线选择问题转化为数学模型,并且通过无向图寻优法获取最佳的航行路线,最后根据不同的估价函数分析出搜索的最佳航线。与Dijkstra算法相比,A~*算法搜索点数少,搜索效率高。  相似文献   

13.
集装箱空箱海上调运优化模型   总被引:2,自引:0,他引:2  
应用线性规划的方法,从船舶公司的角度考虑海上空箱调运优化问题,建立调运优化模型;以调运费用,装、卸箱费用和租箱费用最省为目标,同时考虑客户的需求,供给和运输能力的约束。  相似文献   

14.
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.  相似文献   

15.
This paper traces the evolution of Canadian liner shipping policy from its beginnings, at the time of the initial formation of shipping conferences, in the late nineteenth century, to its current form, as provided by the 1987 Shipping Conference Exemption Act. It is shown that evolution has been associated with a shift in policy orientation from an initial British-based position to a contemporary form that is distincly American in nature. The reasons for this shift are analysed and the similarities and differences between curent Canadian and U.S.A. legislation are identified. The paper shows that the adoption by Canada of an American-style policy became inevitable once the container revolution had physically integrated the transport systems of both nations.  相似文献   

16.
Return to scale are important in container shipping: service operators are continuing to increase the size of their vessels. Mr Seok-Min Lim's article 'Economies of container ship size' (Maritime pollicy and Management,21(2) pages 149-160, 1994) uses a sample of transPacific voyages to evaluate the effect of vessel scale on revenue and cost.Although the results are inconclusive,his study is of value in drawing attention to the revenue-side problems of large containerships. More data need to be collected before the effects of topping up with low-rated cargo on unit revenue retention can be assessed. Meanwhile the pursuit of scale aggravates over-tonnaging. The required response is further rationalization, through the medium of the conferences and the container consortia. In Europe both are under political attack. Operators need to convince the authorities of the soundness of the soundness of their case for adapting these institutions to the neeeds of times.Otherwise the scramble for scale could spell disaster.  相似文献   

17.
Mandatory rules exist in contracts for international liner shipping primarily because of imbalances and non-equity in the allocation of contract responsibilities. The superior bargaining position owned by the carriers depends largely upon liner market monopoly levels, the supply and demand balance between the shipper and carrier, and the cargo volume size of the shippers. With the development of shipping technologies, mode of transport, and shipping competition policy, the unequal comparison of bargaining forces between shippers and carriers changes. When the existing mandatory rule was deemed no longer necessary due to changing circumstances, legislation requirements to restore freedom to contract became apparent. When both sides have equal bargaining power, adoption of the principle of freedom of contract for their business relationships is suitable. The Rotterdam Rules concerning freedom of volume contract construction is based on equal bargaining powers between both sides and responds to the evolving situation of the industry. The Rules represent the development trend of today’s theory of contracts for international liner shipping and the demand for legal and institutional changes.  相似文献   

18.
In the competitive liner shipping market, carriers may utilize revenue management systems to increase profits by using slot allocation and pricing. In this paper, related research on revenue management for transportation industries is reviewed. A conceptual model for liner shipping revenue management (LSRM) is proposed and a slot allocation model is formulated through mathematical programming to maximize freight contribution. We illustrate this slot allocation model with a case study of a Taiwan liner shipping company and the results show the applicability and better performances than the previous allocation used in practice.  相似文献   

19.
In the competitive liner shipping market, carriers may utilize revenue management systems to increase profits by using slot allocation and pricing. In this paper, related research on revenue management for transportation industries is reviewed. A conceptual model for liner shipping revenue management (LSRM) is proposed and a slot allocation model is formulated through mathematical programming to maximize freight contribution. We illustrate this slot allocation model with a case study of a Taiwan liner shipping company and the results show the applicability and better performances than the previous allocation used in practice.  相似文献   

20.
A real liner shipping problem of deciding optimal weekly routes for a given fleet of ships is considered and a solution method for solving the problem is proposed. First, all feasible routes for each ship are generated together with the cost and the duration for each route. The routes are given as input to an integer programming (IP) problem. By solving the IP problem, routes for each ship are selected such that total transportation costs are minimized and the demand at each port is satisfied. The total duration for the routes that are selected for a given ship must not exceed one week.

The real liner shipping problem is solved together with four randomly generated test problems. The computational results show that proposed solution method is suitable for designing optimal routes in several liner shipping problems.  相似文献   

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