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1.
This study focuses on the expected impact of Northern Sea Route (NSR) usage and the Panama Canal (PC) expansion on liquefied natural gas (LNG) imports of Asian countries, from not only the macroeconomic viewpoint but also diversification of the supplying countries. First, the amounts saved from shipping costs due to these events are estimated, based on scenarios on the navigable period of the NSR, transit fee of the NSR considering the exchange rate between the Russian ruble and US dollar, and bunker fuel price. Second, a spatial general equilibrium model based on macroeconomic theory is applied to predict changes in LNG trade patterns and measure economic impacts due to the reduction of shipping costs. Finally, the impacts of NSR usage as well as the PC expansion on LNG imports of Asian countries are discussed based on the calculations. The results show that diversification of supplying countries for LNG imports can be observed, especially in Japan, the largest LNG importer in the world, and other Asian countries are secondarily affected by changes in Japan’s import pattern, with limited impacts on these countries’ national economies.  相似文献   

2.
ABSTRACT

Further to being Greece’s biggest port, Piraeus has been a traditional pole of attraction for a plethora of organisations, companies, and institutions engaged in port- and shipping-related activities. Regional development literature has already indicated that the benefits deriving from adjacency and agglomeration economies are maximised when individual entities are organised in forming business clusters. Therefore, the paper critically addresses the existence of theoretical preconditions to a competitive port–maritime cluster formulation in wider Piraeus area. Based on a thorough review of cluster theory, the basic characteristics of clusters are identified to provide the analytical tools for examining the geographical concentration and economic specialisation in Piraeus. Field research in the form of in-depth interviews with leading shipping- and port-related business representatives and institutional bodies and the analysis of qualitative and quantitative data collected revealed that necessary preconditions for successful cluster formulation are met despite the inexistence of a formally recognised cluster. Two distinct poles of economic activity (shipping and port related) are recognised, demonstrating differentiated clustering behaviours and patterns of interaction with other players. The paper concludes with proposals deriving from this dual cluster structure and governance and the need for innovative, differentiated strategies.  相似文献   

3.
The focus of this paper is the selection of paths for the maritime transportation of crude oil. In addition to transportation cost, the nodes in a maritime transportation network are always affected by extreme events. Therefore, connectivity reliability must be considered during path selection. In this paper, uncertainty variables are introduced to describe the connectivity reliability of nodes under the influence of extreme events, and an uncertain bi-objective programming model with connectivity reliability maximization and transportation cost minimization as objectives is established for path selection. China’s maritime transportation network for crude oil imports is used as a case study to validate the model, the effects of variations in the model parameters on path selection, transportation cost and connectivity reliability are discussed in the case study. The research results provide a basis on which for government decision makers to better plan crude oil transportation strategies.  相似文献   

4.
5.
The extending of a cantilever and transverse moving of a drilling floor enable the jack-up to operate in several well positions after the Jack-up has pitched. The cantilever allowable load nephogram is the critical reference which can evaluate the jack-up's drilling ability, design the cantilever structure and instruct a jack-up manager to make the operations safe. The intent of this paper is to explore the interrelationships between the cantilever position, drilling floor and the loads including wind force, the stand set-back weight etc., through analyzing the structure and load characteristics of the x-type cantilever and the simplified mechanics model with the restriction of the maximum moment capacity of the cantilever single side beam. Referring to several typical position designs load values, the cantilever allowable load nephogram is obtained by using the suitable interpolation method. The paper gives a method for cantilever allowable load design, which is proved reliable and effective by the calculation example.  相似文献   

6.
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   

7.
8.
Full-scale globalisation of trade has been accompanied by a progressive liberalisation of maritime transport. The proliferation of open registries has created a situation in which Port State Control (PSC) has become much more effective than the feeble or non-existent control exercised by those States. This study has been conducted on the influence of the professional profile of inspectors on inspection results. The objective of our paper was to evaluate the impact of PSC inspectors’ professional profile by conducting a case study of the Spanish Maritime Administration. The paper concludes with a discussion of the correlation between deficiencies detected and professional profiles.  相似文献   

9.
[Objectives ] This paper studies a three-dimensional (3D) cooperative path-following control problem in the process of maritime search and rescue for a heterogeneous unmanned cluster system composed of unmanned aerial vehicles (UAVs) and unmanned surface vehicles (USVs).[Methods ] First, kinematic models of the UAVs and USVs are established under a fixed coordinate system and body coordinate system. In order to design a 3D path-following controller suitable for motion control, an air coordinate system is established, and the path tracking error models of the UAVs and USVs are established in the Serret-Frenet coordinate system. Next, a 3D line-of-sight (LOS) guidance law is designed at the kinematic level, and a cooperative path-following control method suitable for heterogeneous clusters of marine vehicles is proposed, allowing the UAVs and USVs to track the preset parameterized path. Finally, the stability of the control system is analyzed based on the Lyapunov stability theory.[Results]The simulation results verify the effectiveness of the proposed cooperative path-following control method for heterogeneous clusters of marine vehicles.[Conclusions]The results of this study can provide references for maritime search and rescue by using the proposed cooperative path-following control method. © 2022 Journal of Clinical Hepatology. All rights reserved.  相似文献   

10.
ABSTRACT

The last few years a great body of research focused on the problems observed in the shipping industry due to the mix of different nationalities on board. Herein, the problem is observed in the managerial level, and specifically to the applied crew management strategies and the philosophy of the shipping companies regarding the issue of multiculturalism. The present paper seeks to elevate the value of human resources in shipping and to underline the potentials that human resource management and cultural diversity management have as a shipping company’s core competency. In a triangulated theoretical framework, the combination of resource-based view, human resource management, and cultural diversity management leads to a framework of choices which include strategies for the management of maritime human resources’ cultural diversity. The paper analyses the practical application of the proposed strategies and the fulfilment of the criteria required for turning crew management to a core competency and gaining sustainable competitive advantage from human resources.  相似文献   

11.
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   

12.
The liner shipping industry has long been characterized by a weekly sailing frequency and schedule unreliability. This research is motivated by the launch of the revolutionary “Daily Maersk” service in late 2011, which introduced daily departures and “absolute reliability” in the Asia–North Europe trade lane. This article analyzes Daily Maersk’s impacts on a shipper’s supply chain inventories and profound implications for the liner shipping industry as a game changer. The quantitative analyses show that the impact of more frequent sailings is most significant on a shipper’s cycle stock, while improving schedule reliability substantially reduces safety stock and pipeline stock. Daily Maersk is most valuable for products that have high value density, high inventory holding cost ratio, low demand variability, and high service level (SL) requirement. These findings imply that the trend of liner alliance/merger/acquisition is likely to continue or even accelerate as shipping lines consolidate fleet capacity to offer more frequent sailings. Rival carriers may step up their involvement in terminal operations to improve schedule reliability. They also need to rethink about their SL targets and clearly define their preferred customer segments.  相似文献   

13.
A ship operating in following and/or quartering seas may be susceptible to broaching-to preceded by the surf-riding phenomenon. Therefore, for the safety assessment of fast vessels such as destroyers and patrol craft, the estimation of the surf-riding condition is important. As shown by previous research, there are two boundaries for ship motion in following and quartering seas. These are the surf-riding threshold and wave-blocking threshold. In this study, the theoretical methods to estimate both boundaries are obtained by making use of Melnikov’s method. In order to validate the formulae, free-running model experiments are conducted in the towing tank. Comparisons between the results obtained from calculations and experiments show good agreement. It is concluded that the formulae based on Melnikov’s method could be applicable to the safety assessment of surface ships.  相似文献   

14.
China’s Belt and Road (BR) initiative is expected to facilitate international trade between the countries involved. In this study, we review the special requirements of wine logistics and the market growth potential of wine consumption in China. A model minimizing generalized logistical costs is developed and applied to wine imports in China, so that the best candidate cities in which to locate transport gateways and distribution centers can be identified. Our analysis suggests that the most preferred gateways are Shanghai, Tianjin, Guangzhou, and Hong Kong, which all have similar delivery costs. In comparison, Beijing and Chongqing have much higher delivery costs, mainly because they do not have good access to marine transport and/or efficient domestic distribution networks. For long-distance intercontinental transport of large volumes of wine, marine shipping remains the only viable delivery mode. However, wine distribution within China extensively uses air, road, and water transport. Therefore, cities with excellent multi-modal transport services are better positioned to become wine logistics gateways. Our study also highlights the importance of value-added services and good government support, which are important factors that influence distribution costs and quality.  相似文献   

15.
Abstract

This article presents the results of an impact assessment of a component of a large scale USAID sustainable fisheries management project initiative aimed at integrating gender and strengthening the role of women in fisheries management in Ghana. The assessment is based on a literature review and qualitative field data collection. It assessed gender integration from three entry points: improving the Ghanaian policy environment for gender in fisheries, empowering women post-harvest processors, and engaging women gleaners in fisheries co-management. The assessment found that an important milestone was the adoption and implementation of the Ghanaian Fisheries Sector’s National Gender Mainstreaming Strategy in 2016. Summarizing the impacts on local post-harvest processors and gleaners, the assessment found that female post-harvest processors have increased capacity, confidence, and engagement in fisheries management. Gender mainstreaming efforts have succeeded in challenging cultural norms about women’s role in fisheries. Women have been exposed to sustainable fisheries management and are better equipped with the knowledge and leadership skills to advocate for good fisheries practices, which they actively demonstrate.  相似文献   

16.
In this paper, the effect of plastic constraint on the initiation of ductile tears in four different shipbuilding structural steels has been experimentally studied by measuring the J-integral and crack opening displacement COD at initiation in three-point bend specimens with deep and shallow notches. Experimental results of seven groups of different strength alloy steels show that both Si and Ji values of ductile tear from the shallow crack specimens which have less constraint flow field are significantly higher than those of deeply notched specimens. Slip-line-field analysis shows that, for shallow crack, the hydrostatic stress is lower than that from standard deeply cracked bend specimen, which develops a high level of crack tip constraint, provides a lower bound estimate of toughness, and will ensure an unduly conservative approach when applied to structural defects, especially if initiation values of COD and J-integral are used.  相似文献   

17.
The interaction of oblique incident water waves with a small bottom deformation on a porous ocean-bed is examined analytically here within the framework of linear water wave theory. The upper surface of the ocean is assumed to be covered by an infinitely extended thin uniform elastic plate, while the lower surface is bounded by a porous bottom surface having a small deformation. By employing a simplified perturbation analysis, involving a small parameter δ(=1), which measures the smallness of the deformation, the governing Boundary Value Problem (BVP) is reduced to a simpler BVP for the first-order correction of the potential function. This BVP is solved using a method based on Green’s integral theorem with the introduction of suitable Green’s function to obtain the first-order potential, and this potential function is then utilized to calculate the first-order reflection and transmission coefficients in terms of integrals involving the shape function c(x) representing the bottom deformation. Consideration of a patch of sinusoidal ripples shows that when the quotient of twice the component of the incident field wave number propagating just below the elastic plate and the ripple wave number approaches one, the theory predicts a resonant interaction between the bed and the surface below the elastic plate. Again, for small angles of incidence, the reflected wave energy is more as compared to the other angles of incidence. It is also observed that the reflected wave energy is somewhat sensitive to the changes in the flexural rigidity of the elastic plate, the porosity of the bed and the ripple wave numbers. The main advantage of the present study is that the results for the values of reflection and transmission coefficients obtained are found to satisfy the energy-balance relation almost accurately.  相似文献   

18.
To rationally assess the consequence of a ship’s hull girder collapse, it is necessary to know the post-ultimate strength behavior of the hull girder including the global deformation and motions under extreme wave-induced loads. In the foregoing research, the authors proposed a numerical analysis system to predict the collapse behavior in waves including the post-ultimate strength behavior. The primary objective of the present paper is to clarify the parametric dependencies of the severity of the collapse in a rational manner. The parameters may include those related to load-carrying capacity and the extreme loads. To this end, an analytical solution to describe the post-ultimate strength behavior is derived. Assuming that a plastic hinge is formed at the midship during the collapse procedure, the whole ship is modeled as a two-rigid-bodies system connected to each other amidship via a nonlinear rotational spring, which represents the nonlinear relationship between the bending moment and the rotational angle. The relationship may be modeled as piece-wise linear curves. It is further assumed that large motions and elastic/plastic deformations of the hull girder may not affect the load evaluations, and that the hull girder is subjected to a large single wave. Some important parameters to predict the severity of the collapse are specified based on the analytical solution.  相似文献   

19.
Simulation-based design hull form optimization has become one of the most effective ways to develop energy-saving ships. However, the traditional method is time consuming and inefficient, so it is difficult to apply it to practical engineering. One of the reasons for this difficulty is that there are numerous parameters for expressing the hull form, making it difficult to find the optimal solution within a short amount of time. Therefore, this paper presents a sensitivity analysis method based on radial basis function and partial least squares regression neural network with uniform design for sampling, to study the sensitivity of local hull parameters of a class of container ships on wave-making resistance performance, and to reduce the number of dimensions in the design space. According to the results of sensitivity analysis, the parameters that are of negligible influence on the objective function can be removed from the optimization model. Comparison of results of the original model and the simplified model shows that the presented sensitivity analysis method can effectively reduce the dimension of the design space so that the time consumed to achieve the optimum is decreased.  相似文献   

20.
This paper evaluates the influence of forecast horizon and observation fit on the robustness and performance of a specific freight rate forecast model used in the liner shipping industry. In the first stage of the research, a forecast model used to predict container freight rate development is presented by exploring the relationship between individual company’s rates and aggregated market rates, and thus assists in dealing with uncertainty and market volatility for a given business situation. In the second stage, a design of experiment approach is applied to highlight the influence of the forecast horizon and observation fit and their interactions on the forecast model’s performance. The results underline the complicated nature of creating a suitable forecast model by balancing business needs, a desire to fit a good model and achieve high accuracy. There is strong empirical evidence from this study; that a robust model is preferable, that overfitting is a true danger, and that a balance must be achieved between forecast horizon and the number of observations used to fit the model. In addition, methodological guidance has also been provided on how to test, design, and choose the superior model for business needs.  相似文献   

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