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1.
Increasing stack heights on container ships and growing volumes of high density cargo have increased the loads and stresses placed on containers, requiring an assessment of current container strength specifications. Growing adoption of terminal automation is also requiring greater standardisation in the codification and marking of containers. However, it is shown that there is widespread misunderstanding of the roles of the IMO and the ISO in regulating and promoting standards in the design, dimensions, ratings, coding, marking and strength of containers. In this paper the legal status of the IMO’s Convention for Safe Containers (CSC) and ISO standards is clarified, and a common container specification framework is developed to assess the extent to which international regulations and standards are aligned. The analysis identifies gaps and inconsistencies between regulations and standards and assesses the impact these have on operations and safety. The study highlights to policy makers anomalies arising from the recent inclusion in the CSC of direct references to ISO standards. Finally, in providing a comprehensive definition of container specifications the paper provides a knowledge base to promote theory building for applied researchers in the field of container technology and operations.  相似文献   

2.
《Marine Structures》2003,16(5):397-415
This paper is the second part of the structure study of double cylindrical shell subjected to hydrostatic external pressure. The author makes researches on the relationship between inner and outer shells of pressurized double cylinders using equilibrium conditions of forces and deformation compatibility conditions with ring plate orthogonally connected to inner and outer shells and puts forward the expressions of longitudinal and circumferential forces of double pressurized cylinder. In this paper, equilibrium equations are established for a double cylindrical shell stiffened longitudinally and transversely and subjected to uniform hydrostatic external pressure by using an adjacent equilibrium method and a solution with high accuracy is presented to calculate theoretically critical pressures of panel buckling and interframe shell buckling. The solution can be used to both the double and single cylindrical shells without longitudinal stiffeners and therefore, it may be applied widely with higher accuracy. Also, some simplified formulae for the engineering application are given to calculate the panel buckling and the interframe shell buckling strengh.  相似文献   

3.
《Marine Structures》2003,16(5):373-395
This paper is the first part of the structure study of double cylindrical shell subjected to hydrostatic external pressure. A calculation method is put forward in the paper to analyse the massive structure strength of double cylindrical pressure shell. The equilibrium equations of double cylinder segments and ring plates are established by using the compatibility condition of orthogonal connection between inner and outer cylindrical shells through ring plates. The equilibrium equations set of cylinder segments may be integrated into the global equation of undetermined parameters by means of correlation matrix analysis and continuity conditions of adjacent shell segments. It may be used to solve accurately and simply deflections and stresses in the structural members at any point in the individual span ranging from single cylinder to double cylinder, locate the structural weakness and allow the researchers to have a comprehensive understanding of the massive structure strength. Model tests show that this method is accurate and reliable and may be adopted to perform a number of effective calculation analysis of engineering for the design of double pressure shell.  相似文献   

4.
The announcement of the Rotterdam Rules, a new convention governing the carriage of goods through maritime transport, was greeted with support and opposition. This commentary analyzes its pros and cons, and argues that when fully implemented, the convention will have a significant impact on the carriage of goods and is poised to boost the volume of maritime trade.  相似文献   

5.
The release of captive dolphins (Tursiops aduncus) from South Korean marine parks, which occurred in 2013, 2015, and 2017, is described and evaluated for its usefulness for conservation of coastal ecosystems. The campaign to free the dolphins created a flagship species, uniting the efforts of national government agencies, local government, and NGOs. However, the Korean management agencies framed the release as a species-specific conservation intervention, while the NGOs brought forward welfare-based demands for the curtailment of cetacean captivity. We argue that the release of the Korean dolphins changed the policy climate, to facilitate two major policy changes: revision of anti-whaling regulations to prohibit capture of cetaceans for exhibit, and improvement of regulations for rescue, rehabilitation, and release of stranded marine animals. Tradeoffs between welfare and conservation concerns are described in terms of risk for the management agency, welfare for the animals, and feasibility of a continued commitment to maintain the viability of the dolphin stock in the wild. The release of captive animals to their native range relies on a single-species conservation focus which poses little risk for management agencies but does not guarantee their continued commitment.  相似文献   

6.
7.
Abstract

The West Coast Groundfish Trawl Catch Share Program was designed to achieve multiple economic goals and objectives, including increasing net benefits, profitability, flexibility, and utilization of harvest allocations. In this article, we leverage seven years of comprehensive cost and earnings data to evaluate progress towards these goals with a focus on harvesters. Our assessment shows that five years post-implementation, net benefits to the nation have doubled, and indicators of productivity and profitability have increased. The fleet that targets Pacific whiting has seen the largest gains, due in part to increases in total allowable catch and the elimination of the race-to-fish. However, increased revenues have not been realized to the degree that was expected for harvesters targeting non-whiting groundfish, partly due to lower than predicted consolidation and relatively low quota utilization. Economic outcomes indicate that tradeoffs exist between certain objectives of the program, specifically between achieving full utilization and flexibility for harvesters. Results are discussed in the context of the design and evaluation of catch share programs for diverse, multispecies fisheries.  相似文献   

8.
This paper reviews a number of themes that have played a crucial role in the debate on alternative contracting regimes for the provision of urban bus services. We have selected four crucial issues to reflect on: (i) contractual regimes (in particular competitive tendering as compared to negotiated performance-based contracts, as means to award the rights to provide service); (ii) contract completeness (focussing on ex ante and ex post elements); (iii) building trust through partnership; and (iv) tactical or system level planning for bus services. Experience in these areas suggests that competitive tendering has frequently not lived up to expectations and that negotiation is likely in many circumstances to deliver better value for money.  相似文献   

9.
The attractiveness of ports is usually a pre-requisite and necessary condition for ports to achieve competitiveness, as well as the springboard to explore the competitive advantages of ports. To determine whether a port is competitive, it is necessary to explore whether it boasts certain factors that make the port attractive to users. The main purpose of this article is to apply the Analytic Hierarchy Process (AHP) method and the Decision Making Trial and Evaluation Laboratory (DEMATEL) technique to evaluate key determinants of attractiveness and their cause/effect relationships for container ports in Taiwan. The empirical results showed that: (1) Top six determinates of attractiveness for container ports are ‘ample cargo sources,’ ‘favorable port charges,’ ‘dense ship network and routes,’ ‘low transshipment costs,’ ‘efficient wharf operations,’ and ‘adequate wharfs and back-line land,’ respectively. (2) Among the above six determinants of attractiveness, ‘ample cargo sources’ is the cause determinant. Three determinants of port attractiveness, ‘favorable port charges,’ ‘dense ship network and routes,’ ‘low transshipment costs,’ which are the effect determinants. They are affected by the determinants of attractiveness of ‘ample cargo sources’. In addition, this study discusses the above findings and expects to provide the study results to Taiwan’s port authorities for reference.  相似文献   

10.
Recent transport sector liberalisation, as well as global economic crisis, is favouring the implementation of transport infrastructure projects through Public–Private Partnerships (PPP). However, there is a debate as to whether PPP schemes are a better option than conventional procurement. To this end, an evaluation framework is proposed, to assess which of these two alternative schemes for transport projects financing is preferable for the public. The proposed framework is complimentary to the Value for Money (VfM) approach and is based on a Multi Criteria Analysis (MCA). The first step is the estimation of the Public Sector Comparator (PSC) for the case of conventional procurement, dealing with construction, maintenance and operation costs revenues, as well as any costs associated with risks undertaken by the public. As for the PPP case, it includes any payments by the public sector and related risks costs. The MCA is then applied only if the PPP is found preferable for the public sector. The latter considers additional impacts, including among others the social attributes of a particular scheme, job creation, environmental impacts and safety and security aspects. The proposed framework was applied to a pilot Bus Rapid Transit (BRT) corridor infrastructure project in the city of Indore, India, in order to demonstrate its validity. The framework and its application could provide useful guidance when considering PPP for a transport project, since it demonstrates in a transparent way the society's attitude towards this project, something that is critical to its acceptance.  相似文献   

11.
For the design of maritime structures in waves, the extreme values of responses such as motions and wave impact loads are required. Waves and wave-induced responses are stochastic, so such responses should always be related to a probability. This information is not easy to obtain for strongly non-linear responses such as wave impact forces. Usually class rules or direct assessment via experiments or numerical simulations are applied to obtain extreme values for design. This brings up questions related to the convergence of extreme values: how long do we need to test in order to obtain converged statistics for the target duration? Or, vice versa: given testing data, what is the uncertainty of the associated statistics? Often the test or simulation duration is cut up in ‘seeds’ or ‘realisations’, with an exposure duration of one or three hours based on the typical duration of a steady environmental condition at sea, or the time that a ship sails a single course. The required number of seeds for converged results depends on the type of structure and response, the exposure duration, and the desired probability level. The present study provides guidelines for the convergence of most probable maximum (MPM) wave crest heights and MPM green water wave impact forces on a ferry. Long duration experiments were done to gain insight into the required number of seeds, and the effect of fitting. The present paper presents part 1 of this study; part 2 [1] presents similar results for wave-in-deck loads on a stationary deck box.  相似文献   

12.
In September 2015, the United Nations (UN) officially adopted the 2030 Agenda for Sustainable Development together with 17 sustainable development goals (SDGs) (UN, 2016). The attainment of the SDGs requires a strong commitment by all UN Member States, not least by the Member States at the International Maritime Organization (IMO). This empirical research aims to identify the role and challenges of stakeholders at IMO, when implementing the UN’s 2030 Agenda in the international maritime transport domain using a grounded theory approach. This paper describes the methodology and the analytical process undertaken and presents the main findings based on empirical data. The results are presented as a set of six propositions. The first proposition presents the phenomena engulfing Member States at IMO stemming out from lack of knowledge and policy incoherency on the 2030 Agenda at national level. The other five propositions suggest how these challenges could potentially be best alleviated through an IMO-led strategy on sustainable development within the context of the 2030 Agenda, supported by an appropriate governance structure that sees the introduction of strategic actors for coordinating the implementation of the SDGs at national level. With the support of a Task Force, and by also making use of the IMO Member State Audit Scheme (IMSAS), to create more awareness and ownership, the strategic actors could work towards balancing the three dimensions of sustainable development—the economic, the environmental, and the social dimensions—which were found to be imbalanced in the international maritime transport domain.  相似文献   

13.
Scotland's low accessibility is reflected in the limited share of Scottish unitised freight traffic coming through Scottish ports. This paper will discuss site development strategies to overcome Scotland's double peripherality (i.e. both physically and institutionally) by restructuring transport chains of large shippers through new corridors. Three competing logistics concepts will be discussed, beginning with the existing load centre terminal that provides direct access to the distant main ports. Second, port-centric logistics based at Scottish ports, and finally, offshore port-centric logistics utilising maritime links to a port-based distribution centre in Zeebrugge. The paper has two interlinked aims. First, to provide a firm theoretical grounding for recent maritime transport geography concepts, which has been lacking in the literature. This will be achieved by examining peripherality and responses to this by states at different scales, thus exploring how the three concepts in this paper can be viewed as attempts at spatial fixes of mobile capital. The second aim develops out of the first, and will explore how the perspective of space is treated in maritime geography as compared with other areas of geography. As a result, the paper pursues a cross-disciplinary approach by utilising theory from economic geography and political geography.  相似文献   

14.
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   

15.
Despite the promises of simulations to contribute to learning in safe-critical domains, research suggests that simulators are poorly implemented in maritime education and training systems. From the current state of research, it is far from evident how instruction in simulator-based should be designed and how skills trained in bridge simulators should be assessed and connected to professional practice. On this background, this article aims to investigate the role of instructions and assessments for developing students’ professional competencies in simulation-based learning environments. The research draws on ethnographic fieldwork and detailed analyses of video-recorded data to examine how maritime instructors make use of simulator technologies in a navigation course. Our results reveal an instructional practice in which the need to account for general principles of good seamanship and anti-collision regulations is at the core of basic navigation training. The meanings of good seamanship and the rules of the sea are hard to teach in abstraction because their application relies on an infinite number of contingencies that have to be accounted for in every specific case. Based on this premise, we stress the importance of instructional support throughout training (from briefing thorough scenario to debriefing) in order for the instructor to bridge theory and practice in ways that develop students’ competencies. Our results highlight, in detail, how simulator technologies enable displaying and assessing such competencies by supporting instructors to continuously monitor, assess, and provide feedback to the students during training sessions. Moreover, our results show how simulator-based training is related to the work conditions on board a seagoing vessel through the instructor’s systematic accomplishments. Finally, our results highlight the close relationship between technical and non-technical skills in navigation, and how these are intertwined in training for everyday maritime operations.  相似文献   

16.
In the assessment of wave-in-deck loads for new and existing maritime structures typically model tests are carried out. To determine the most critical conditions and measure sufficient impact loads, a range of sea states and various seeds (realisations) for each sea state are tested. Based on these measurements, probability distributions can be derived and design loads determined. In air gap model testing usually only few, if any, impact loads occur per 3-hour seed. This can make it challenging to derive reliable probability distributions of the measured loads, especially when only a few seeds are generated. In addition wave impact forces, such as greenwater loading, slamming, or air gap impacts are typically strongly non-linear, resulting in a large variability of the measured loads. This results in the following questions: How many impacts are needed to derive a reliable distribution? How is the repeatability of individual events affecting the overall distribution? To answer these questions wave-in-deck model tests were carried out in 100 x 3-hour realisations of a 10,000 year North Sea sea state. The resulting probability distributions of the undisturbed wave measurements as well as the measured wave-in-deck loads are presented in this paper with focus on deriving the number of seeds and exposure durations required for a reliable estimate of design loads.The presented study is Part 2 of a combined study on guidance for the convergence and variability of wave crests and impact loading extreme values. The data set of Part 1 ([1]) is based on greenwater loads on a sailing ferry and the data set of Part 2 on wave-in-deck loads on a stationary deck box.  相似文献   

17.
This article evaluates factors driving perception of risk and uncertainty in fisheries in Iwaki City, Fukushima Prefecture, Japan, following the Fukushima Dai'ichi nuclear accident. Particular attention is paid to lessons that may be learned for managing uncertainties and risks in coastal management more generally. The 2011 accident has had profound effects on Fukushima fisheries. Commercial coastal fisheries have been stopped since, and efforts to understand and monitor the effects of marine radioactive contamination on produce from the sea continue. Small-scale trial fisheries have, however, re-commenced with a view to gradually re-starting Fukushima fisheries over time. Drawing on in-depth interviews, discussion groups, and field observations from Iwaki and Fukushima Prefecture more widely, three factors are discussed: the role of trusted local-level points of contact; the value of transparent monitoring and screening that acknowledges remaining limitations and uncertainties; and the importance of taking seriously the cultural dimensions of rapid and potentially irreversible environmental change.  相似文献   

18.
A contract establishes a mutual relationship between an authority and an operator. From the point of view of the authority, it is a tactical level mechanism to achieve the strategic objectives of government. Management of contractors translate the requirements of contracts into operational practices to guide the day-to-day work of staff for the delivery of services. Much can go wrong with contracts for the provision of public transport services. Workshop participants identified and ranked 25 potential risk factors. The five most important factors, which relate to objectives, tender assessment, allocation of risks, financial viability and dispute management, were examined drawing on the 11 papers presented to the workshop. Matters that work, that do not and would make the most difference to the success of contracts were identified.  相似文献   

19.
The existing risk weighing on vessel, crew and ecosystem in the Arctic and more globally in Polar waters promoted the adoption of the Polar Code (PC) early 2017, a mandatory international legal framework intended for enhanced safety and environmental protection. While the substance of the PC has been extensively analyzed, few studies have focused on the underlying relationships between the PC and underwriters. Based on an extensive literature review, documentary materials and interviews with insurance companies, this article conceptualizes the PC as a “toolbox” and analyzes how underwriters can exploit it in their work within the emerging Arctic market. The PC does not only regulate the navigation in Arctic waters in legal terms, but is also aimed at mitigating risks in the Polar areas through the identification of hazard sources and proceduralization of risk assessment. As a result we observe a certain “Polar Code paradox”. Even though the PC is a risk-based instrument and constitutes a key step for improving ship insurability, it has only limited capacity to assist underwriters in assessing risks and insuring vessels. Marine insurers still face a lack of data and high pending uncertainties leading them to exercise extreme caution with Arctic risks appraisal.  相似文献   

20.
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