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1.
The street-turn option represents a major strategy for the profitability of shipping companies supplying container-based transportation. This option consists in the distribution of trucks delivering loaded containers to import customers, the subsequent allocation of empty containers to export customers and the final dispatch of loaded containers to departure ports. However, the determination of truck routes is a time-consuming activity for shipping companies, because available information can suddenly change while they are making their decisions. In this paper we aim to propose a decision support tool to quickly determine truck routes and implement the street-turn strategy. This tool is based on an optimization model determining the allocation of empty containers between customers and defining truck routes in a post-optimization phase. We compare routes resulting from the proposed model to the decisions of a real shipping company. Early results indicate that this approach represents a promising support for shipping companies in dealing with street-turns. It can significantly reduce distances travelled by trucks and times requested to determine routes.  相似文献   

2.
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.  相似文献   

3.
通航历时对沿海散货港区航道通过能力的影响分析   总被引:3,自引:0,他引:3  
航道是整个港航生产作业系统的一部分,其通过能力影响因素众多,计算过程复杂。在分析众多因素的前提下,运用Arena仿真软件建立散货港区船舶进出港作业过程仿真模型。仿真结果表明:单线航道通过能力与船舶通航历时之间呈负指数分布关系,并且AWT/AST值越大,其负指数分布曲线拟合度越高;双线航道通过能力不受通航历时的影响。  相似文献   

4.
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   

5.
方艳  代乾  李建军 《船舶》2006,(5):54-57
该文对油船惰性气体系统进行了仿真研究,并用V isua l B as ic语言研发了一套包括烟气惰性气体系统和独立发生器惰性气体系统的软件系统。这个系统既可用于油船船员的特殊培训,也可作为航运院校的辅助教学软件。  相似文献   

6.
This study explores how Management Control Systems (MCS) enhance the performance of shipping companies. Based on data collected from semi-structured interviews, MCS are distinguished in three categories according to the purposes they fulfill: “Basic MCS” are implemented in order to set standards and support basic operations of the business, “Cost MCS” collect information about cost minimization while “External Information MCS” focus on compliance with the requirement of the cargo owners. Furthermore, evidence collected through a survey instrument addressed to shipping companies located in Greece suggests that the choice of MCS is contingent upon the strategy pursued by the shipping companies. Moreover, this paper tests whether shipping companies with an optimal fit between their strategies and their MCS experience superior business performance and a higher perceived usefulness of MCS. Results reinforce the notion that the performance of the shipping companies is contingent on the use of those control systems which are consistent with their strategies and a number of control variables such as experience of the person implemented the MCS, the size, and age of company.  相似文献   

7.
Developments in UK shipping: the tonnage tax   总被引:1,自引:0,他引:1  
The new UK Government, elected in May 1997, came to power with a commitment to reverse the decline of the UK shipping industry and enhance the employment prospects of UK seafarers. The Government commissioned Lord Alexander of Weedon to investigate the case for a tonnage tax. In this paper, the economic arguments for supporting the UK shipping industry are reviewed. There is some evidence that the UK holds a comparative advantage in world markets in key sectors of the shipping industry and on-shore maritime related activities, but is being undermined by lower foreign taxes. In the absence of government support, the UK shipping industry is likely to continue to decline, and, by further reducing the supply of qualified UK ex-seafarers, put at risk the successful on-shore activities. Various measures that might be used to support a national shipping industry, e.g. a tonnage tax, are considered. The paper concludes by discussing the likely impact of the tonnage tax on the UK's shipping industry.  相似文献   

8.
The new UK Government, elected in May 1997, came to power with a commitment to reverse the decline of the UK shipping industry and enhance the employment prospects of UK seafarers. The Government commissioned Lord Alexander of Weedon to investigate the case for a tonnage tax. In this paper, the economic arguments for supporting the UK shipping industry are reviewed. There is some evidence that the UK holds a comparative advantage in world markets in key sectors of the shipping industry and on-shore maritime related activities, but is being undermined by lower foreign taxes. In the absence of government support, the UK shipping industry is likely to continue to decline, and, by further reducing the supply of qualified UK ex-seafarers, put at risk the successful on-shore activities. Various measures that might be used to support a national shipping industry, e.g. a tonnage tax, are considered. The paper concludes by discussing the likely impact of the tonnage tax on the UK's shipping industry.  相似文献   

9.
This paper considers the question whether the present recovery of shipping means a return to pre-crisis conditions with hegemony of OECD shipping or whether shipping has irrevocably changed. Shipping is losing its national character as ship management firms contribute towards the fragmenting of traditional ship-owning firms into separately managed activities, making shipping more footloose as an industry and facilitating relocation in least cost factor markets. Trade cycles may be at work in shipping like those observed in many industrial markets, beyond the scope of any single government's ability to control. The dispersion of shipping and shipping firms away from the historical concentration in a few traditional maritime powers towards low-cost countries must be seen as a manifestation of a secular trend, giving rise to a profound reorganization not only of shipping markets but of shipping itself.  相似文献   

10.
针对越来越多的企业开始采用分布式系统架构来构建应用系统,详细分析了分布式应用系统集成测试的现状和面临的诸多问题,通过对IBM Rational集成测试工具套件进行深入研究和大量实践,提出了基于Rational的分布式系统集成测试解决方案.该方案已成功应用于航运信息系统的集成测试中,有效提高了测试工作的劳动生产率、降低了成本,并充分保证了系统的交付质量.  相似文献   

11.
This study examines whether the implementation of corporate social responsibility (CSR) and provision of service quality (SQ) to satisfy shippers result in financial synergies or trade-offs for shipping firms. To address this question, a contingency framework was introduced in this study. The literature was first reviewed for hypotheses development, followed by interviews with eight industry practitioners. Subsequently, an internet survey was administered to 156 shipping firms in Singapore, and the obtained data were analysed using path model analysis and simple slope analysis. The results indicate that CSR complements SQ and provides additional but modest financial contribution to shipping firms via customer satisfaction. In addition, synergistic interactions between SQ and CSR were found. Although there are financial synergies from the implementation of CSR and provision of SQ, the analysis reveals that CSR should only be engaged when a shipping firm is fairly competent at delivering quality shipping services. This paper contributes to both theory and practice by framing business decisions on implementing CSR under contingency theory and offering a strategic approach to managing SQ as well as CSR of shipping firms.  相似文献   

12.
The maritime policy of the US has evolved over more than 100 years from the support of US shipping through mail and fleet auxiliary contracts before the turn of the century, to the present array of direct and indirect Government aids and regulations based on the assumption that a strong maritime industry composed of both US-flag shipping and US-shipbuilding capacity is essential for the economic well-being and defence of the country. Notwithstanding massive direct and indirect aid to the US merchant marine, amounting to well over a billion dollars a year in recent years, US shipping and shipbuilding has declined dramatically and now comprises less than 3% of world shipping. Only 2.8% of US foreign trade by volume and 6% by value is today carried in US flag ships. Government aids constitute well over 33% of total revenues of US-flag shipping.

The traditional argument for US Government support has been the need for cost parity to permit US-flag shipping to compete effectively in international trade against foreign shipping serving the same routes with presumably lower operating costs. This argument is difficult to sustain today, as vessel costs of many other industrialized nations are now about equal to those of US-flag ships.

In 1970 the US enacted a new, vastly more liberal, maritime act for the support of the US maritime industry. Notwithstanding its even more liberal terms and elimination of the strict cost-parity interpretation, the US maritime industry continues its decline. The recent bankruptcy of two old, established subsidized shipping companies has caused tremors in the industry, yet no new ideas, policies, or plans seem to be forthcoming. It is the objective of this paper to study the development and effects of various historic US Government policies relating to the support of the US maritime industry, and evaluate the positions taken by proponents or opponents of the maritime policy leading to the policy development.

The decision processes are studied by evaluating literature on the evolution of Congressional, administration, industry, and labour interest and positions on the issue of Government aid to the maritime industry. The impact and effectiveness of various elements of past and present US maritime policy is evaluated in relation to the stated objectives. The alternatives to these policies are reviewed in the light of the changing US position in international trade, military strategy, and political objectives. In addition the effectiveness of the present and alternative policies is evaluated as it is and will be affected by changing technology in use, composition of ownership, and operations of US-flag shipping and shipbuilding.  相似文献   

13.
针对目前内河航运中普遍使用VHF语音通信进行船舶信息交流的缺点,设计了一种基于自组织无线数据通信、GPS定位、嵌入式软硬件设计和电子江图等关键技术实现的内河船舶信息自动报告系统,研制的实验室样机实现了自动感知临近船舶并对距离过近的危险船舶报警、船舶向岸基设备自动发送相关航运信息等功能。该系统具有运营低成本、自动准确报告船舶信息的特点,能够提高内河航运安全技术水平。  相似文献   

14.
Following the introduction of tonnage tax for UK-based shipping companies in 2000, the industry now has the opportunity to opt for a tax regime that is beneficial in contrast to the corporation tax applied to most other sectors. This paper aims to summarize the tonnage tax scheme and then to go on to assess whether its introduction was appropriate. In doing so, it assesses whether the benefits it brings to the UK shipping industry are in fact fiscally justifiable in terms of the advantages that have been suggested recently by a number of commentators. These are claimed to derive from the comparative advantage of the UK shipping industry, the need for more skilled on-shore shipping staff with sea-going experience, and in terms of sustaining the maritime cluster typified by the maritime activities of the City of London.  相似文献   

15.
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.  相似文献   

16.
Since its advent, the liner shipping industry has been characterized by fierce competition and cooperation amongst the member carriers. In recent years, almost all the liners have sought extensive cooperation with others, as reflected mainly by the formation of strategic shipping alliances. Despite this, there are still some liners who prefer the 'go-it-alone' policy and have achieved relative success. It seems that cooperation is not always necessary for a liner company's success. It follows that a study that aims to find the rationale behind liner cooperation (or non-cooperation) is of great significance. Over many years of development, game theory has proved to be a useful tool in the study of economics. It is analytically applicable in this market. With these arguments in mind, this paper aims to apply cooperative game theory to analyse co-operation among members of liner shipping strategic alliances. This will involve: (i) presenting a detailed and systematic analysis of liner shipping strategic alliances: (ii) a concise overview of the development of game theory with specific focus on cooperative game theory, and (iii) deducing a conceptual framework through the application of cooperative game theory to liner shipping strategic alliances. The accomplishment of the aforementioned objectives will enhance understanding of inter-organizational relationships and decision-making behaviour in the liner shipping sector.  相似文献   

17.
Since its advent, the liner shipping industry has been characterized by fierce competition and cooperation amongst the member carriers. In recent years, almost all the liners have sought extensive cooperation with others, as reflected mainly by the formation of strategic shipping alliances. Despite this, there are still some liners who prefer the ‘go-it-alone’ policy and have achieved relative success. It seems that cooperation is not always necessary for a liner company's success. It follows that a study that aims to find the rationale behind liner cooperation (or non-cooperation) is of great significance. Over many years of development, game theory has proved to be a useful tool in the study of economics. It is analytically applicable in this market. With these arguments in mind, this paper aims to apply cooperative game theory to analyse co-operation among members of liner shipping strategic alliances. This will involve: (i) presenting a detailed and systematic analysis of liner shipping strategic alliances: (ii) a concise overview of the development of game theory with specific focus on cooperative game theory, and (iii) deducing a conceptual framework through the application of cooperative game theory to liner shipping strategic alliances. The accomplishment of the aforementioned objectives will enhance understanding of inter-organizational relationships and decision-making behaviour in the liner shipping sector.  相似文献   

18.
A key question is whether the service quality instruments developed for other services’ industries may be used to gauge service quality perceptions in shipping. Grounded on similar studies that test the most widely used American service quality instrument, SERVQUAL, in the commercial shipping sector, this study examines its applicability in the passenger shipping realm. Based on a survey of 436 passengers in Piraeus port, SERVQUAL's five main dimensions have been checked regarding their fit with the use of Confirmatory Factor Analysis. Results support that this is a valid instrument for measuring service quality in passenger shipping besides certain considerations regarding its dimensionality. A more parsimonious two-factor model seems more applicable and should therefore be also considered. Finally, it is evident from the study that passengers place more importance to the physical than the interactive elements of service to form their overall satisfaction.  相似文献   

19.
介绍水运交通电视监控图象通过电话线路的传输技术、相应的硬件装置、软件框图以及软件特点。特别是针对水运交通电视监控图象 ,对 JPEG编码标准作了修改 ,以进一步提高压缩比 ,以及自编调制解调器程序以充分发挥调制解调器的传输速率。最后介绍达到预期效果的系统性能测试及现场试验结果  相似文献   

20.
根据运输的“范围经济性”原理,阐述了集装箱航运服务组合拍卖的适用性,围绕价值因素和价值评价因素,分析了集装箱航运服务组合拍卖的比较优势,结合集装箱航运服务的特点,以拍卖者效用最大化和投标者总估值最大化平衡为目标,设计出了组合拍卖的机制和运作程序;针对组合拍卖中的竟胜标问题,建立了集装箱航运服务组合拍卖的一般优化模型,并通过引入集装箱航运服务质量属性参数和运量限制等约束条件,对其进行了改进。从而为实现集装箱航运服务在线拍卖提供理论支持和计算平台。  相似文献   

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