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1.
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   

2.
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   

3.
This study examines how to incorporate the inventory costs of containerized cargoes into existing liner service planning models such that the designed networks could be improved while not causing extra modeling/computational burden. Two approaches are compared: (i) not considering the inventory costs at all and (ii) incorporating the inventory costs associated with onboard time and those related to transshipment by assuming a fixed connection time. The two models are compared with the ideal model capturing the exact inventory costs on a route choice problem and a capacity planning problem based on extensive randomly generated and practical numerical experiments. The results show that: first, ignoring the inventory costs in service planning models may lead to network design with much higher costs (poor network design decisions); second, in service planning models assuming weekly frequency, the inventory costs associated with onboard time could be formulated exactly, and those related to the connection time of weekly services could be approximated by assuming fixed connection time of 3.5 days for ports with 1 day’s minimum connection time and 4.5 days for ports with 2 days’ minimum connection time.  相似文献   

4.
Significant pro-competitive changes were made to the Shipping Act by the Ocean Shipping Reform Act (OSRA). The most notable of these was the shift away from public tariffs and publicly available contract rates to confidential rates using individually negotiated service contracts. The number of individual member service contracts has risen dramatically since OSRA went into effect in 1999. These statistics support the argument that OSRA was able to bring more competition to the industry. However, the theory and empirical evidence of the Act’s success in improving the performance of the liner industry serving the Transatlantic and Transpacific trade routes, which are two major trunk roads subject to the jurisdiction of the US, are not so compelling. This article employs the theory of joint product to assess the impact of OSRA on the shipping market structure and competition of two major east–west arteries after 1999. This article considers head haul and backhaul container shipments as joint products. Two simple statistical equations are derived to reinterpret Smith’s condition of joint product. The empirical results confirm that the market structure of Transatlantic and Transpacific trade lanes are competitive.  相似文献   

5.
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   

6.
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.  相似文献   

7.
This paper will examine the impact of continuous and increasing change in the shipping sector of Eastern Europe with particular reference to the liner sector in Poland one of the more dynamic markets that has emerged since the political, economic and social changes of the late 1980s. Polish Ocean Lines, and in particular POL Levant, a relatively new, commercialized subsidiary operating in the private sector, are taken as case studies to assess the new structures that are emerging in the marketplace.  相似文献   

8.
9.
This paper deals with the measurement of the network complexity of some selected shipping groups, also identifying the contribution of co-operative agreements among carriers. The empirical investigation is focused on: (i) the analysis of the distribution of the carrying capacity per range; and (ii) the comparison of that capacity with the throughput handled in the port facilities of the group. These variables are interpreted in the light of the impact that alliances have on the geographical wideness of the services supplied by each partner. This factor also allows to depict how the cultural and political origin of shipping lines affects the decision of joining an alliance and the outcomes deriving from such co-operation.  相似文献   

10.
This paper deals with the measurement of the network complexity of some selected shipping groups, also identifying the contribution of co-operative agreements among carriers. The empirical investigation is focused on: (i) the analysis of the distribution of the carrying capacity per range; and (ii) the comparison of that capacity with the throughput handled in the port facilities of the group. These variables are interpreted in the light of the impact that alliances have on the geographical wideness of the services supplied by each partner. This factor also allows to depict how the cultural and political origin of shipping lines affects the decision of joining an alliance and the outcomes deriving from such co-operation.  相似文献   

11.
The fleet deployment problem is an important planning problem in liner shipping. It deals with optimally assigning voyages to available vessels in the fleet and determining vessel routes and schedules in a way that minimizes costs or maximizes profit. This paper presents a new model for a fleet deployment problem in liner shipping, and we also propose a multi-start local search heuristic to solve the problem. The heuristic has been embedded in a prototype decision support system (DSS) that has been implemented and tested at Höegh Autoliners, a major global provider of ro-ro (roll-on roll-off) vehicle transportation services. The heuristic was able to produce high-quality solutions within a few minutes to a real planning problem with more than 55 vessels and 150 voyages over a planning horizon of 4–6 months. Tests indicated that the solutions suggested by the DSS gave between 2 and 10% improvements compared with solutions from manual planning. What is almost equally important is that using the DSS can ease the planning process.  相似文献   

12.
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.  相似文献   

13.
14.
In the course of the last two decades Korean shipping has emerged as a major player in the liner market. In 1970 there was not a single container ship in the Korean fleet; yet, within the next two decades, shipping companies from Korea have become included among the top 10 liner operators in the world, in the context of a spectacular ascent of Asian companies in international container shipping. During the same period the organization of liner shipping itself underwent major changes. In the 1970s and 1980s, pools and powerful consortia prevailed, maximizing frequency and optimizing fleet deployment under pressure from the high investment entailed by containerization. The era of consortia, however, came to a close in the early 1990s; intermodalism and the expansion of the major liner companies into forward and backward segments of the transport chain rendered them inflexible for pursuing individual strategies of product diversification with a view to larger market shares. Global alliances were finally born as a result of a major reshuffling of co-operation agreements and of the globalization of the production process on the demand side. The aim of this paper is to follow and assess the options available to an aggressive low-cost national fleet in its journey to competitive maturity through a period of changing organization of liner shipping, focusing on the course of the leading Korean container company, and one of the largest in the world today, Hanjin. It highlights at the same time both the deep structural changes which liner shipping has undergone in the last two decades and the effects of current changes, such as the recent wave of mergers in this sector.  相似文献   

15.
The environment issue is one of the significant challenges that the liner shipping industry has to face. The International Maritime Organization (IMO) has set a goal to reduce greenhouse gas (GHG) emissions from existing vessels by 20–50% by 2050 and develop the Energy Efficiency Operational Indicator (EEOI) as a measure for energy efficiency. To achieve this goal, IMO has suggested three basic approaches: the enlargement of vessel size, the reduction of voyage speed, and the application of new technologies. In recent times, liners have adopted slow steaming and decelerated the voyage speed to 15–18 knots on major routes. This is because slow steaming is helpful in reducing operating costs and GHG emissions. However, it also creates negative effects that influence the operating costs and the amount of GHG emissions at the same time.

This study started with the basic question: Is it true that as voyage speed reduces, the operating costs and CO2 emissions can be reduced at the same time? If this is true, liners will definitely decelerate their voyage speed themselves as much as possible so that they can increase their profits and improve the level of environmental performance. However, if this is not true, then liners will concentrate just on increasing their profits by not considering environmental factors. This led the authors to set out three objectives: (1) to analyze the relationship between voyage speed and the amount of CO2 emissions and to estimate the changes by slow steaming in liner shipping; (2) to analyze the relationship between voyage speed and the operating costs on a loop; and (3) to find the optimal voyage speed as a solution to maximize the reduction of CO2 emissions at the lowest operating cost, thus satisfying the reduction target of IMO.  相似文献   

16.
列举了班轮运输业的四大垄断形式,简要介绍了主要航运国家的反垄断豁免规制,分析了反垄断豁免的利弊,预测了反垄断豁免的演变趋势,提出了对我国发展班轮运输业的建议.  相似文献   

17.
This paper examines the changing position of Polish Ocean Lines (POL) container shipping activities in the North Atlantic, in the light of social, political and economic changes occurring in Poland. An analysis is made of alternative ways of assessing company position—ranging from the qualitative to the quantitative—and that of a qualitative framework approach is selected. Application of this framework using POL as a case study provides an indication of positional change between 1988 and 1993 reflecting the period of major change in Eastern Europe.  相似文献   

18.
19.
The background and the literature in liner fleet scheduling is reviewed and the objectives and assumptions of our approach are explained. We develop a detailed and realistic model for the estimation of the operating costs of liner ships on various routes, and present a linear programming formulation for the liner fleet deployment problem. Independent approaches for fixing both the service frequencies in the different routes and the speeds of the ships, are presented.  相似文献   

20.
Extending and improving an earlier work of the second author, an Integer Programming (IP) model is developed to minimize the operating and lay-up costs for a fleet of liner ships operating on various routes. The IP model determines the optimal deployment of an existing fleet, given route, service, charter, and compatibility constraints. Two examples are worked with extensive actual data provided by Flota Mercante Grancolombiana (FMG). The optimal deployment is solved for their existing ship and service requirements and results and conclusions are given.  相似文献   

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