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991.
992.
Nowadays,there are many studies conducted in the field of marine hydrodynamics which focus on two vessels traveling and floating in sufficiently close proximity to experience significant interactions.The hydrodynamic behavior of parallel moving ships in waves is an interesting and important topic of late.A numerical investigation has been carried out for the prediction of wave exciting forces and motion responses of parallel moving ships in regular waves.The numerical solution was based on 3D distribution technique and using the linear wave theory to determine the exciting forces and ship's motion.The speed effects have been considered in the Green function for more realistic results.The numerical computations of wave exciting forces and motion responses were carried out for a Mariner and Series 60 for the purpose of discovering different Froude numbers and different separation distances in head sea conditions.Based on the numerical computations,it was revealed that the sway,roll and yaw have a significant effect due to hydrodynamic interaction. 相似文献
993.
The evolution of maritime logistics as an emerging discipline has resulted, to a large extent, from the increasing and varied demands of shippers and customers and the rapidly changing role of ports in the context of supply and logistics chains. Scholars are becoming increasingly aware of the need to integrate logistics and supply chain management concepts in the maritime transportation chain and operations. This article aims to provide a review and foundation for understanding the domain of maritime logistics and to assess its potential as an emerging discipline. To do so, a framework for understanding the various aspects of maritime logistics strategy and implementation is developed. A synthesis of the existing knowledge on maritime logistics is done by integrating diverse explorations forming the basis of this framework. We draw upon the literature on maritime transport and ports and primarily theliterature that analyses concepts by adopting an economic or management perspective. 相似文献
994.
ABSTRACTThe shipping market is volatile. In general, the shipping market cycle shows four stages, through—recovery—peak—collapse, while a upward trend lasts for 7~8 years and a downward trend for another 7~8 years. So the market’s bubble is not sustainable but always ends in a recessionary trend. The economic cycle is common knowledge and an axiom of the shipping industry, but many ship-owners take no account of it. Previous study stated that ship-owners’ fears, triggered by a violently changeable market, make them mimic the crowd mind or herd mentality, following market sentiment. This study aims to measure the effects of herding behavior (HB), triggered by market sentiment, on the shipping market. We attempt to address two research questions: (1) How does HB arise, and what course does it follow? (2) How many vessels (or how many tons) were purchased under the influence of HB? We estimate that 50.5% (227.8 vessels) of the total vessels or 30.4% (3,670.2 tons) of the total tonnage were purchased under the influence of HB. Looking at international finance, we found that ship investment HB is a very strong factor of the recent shipping market, at least in Korea. 相似文献
995.
船桥碰撞及桥梁防撞结构研究 总被引:4,自引:0,他引:4
对某桥梁防撞结构的碰撞过程进行了数值模拟。介绍了船桥碰撞数值仿真中所涉及的关键技术,研究了船桥碰撞力,碰撞损伤变形、能量吸收及防撞结构各构件的变形情况,并对其进行了详细分析。数值模拟是用大型非线性动态响应分析程序MSC/Dytran来完成的。 相似文献
996.
周兰 《武汉船舶职业技术学院学报》2013,(4):71-73
本文通过对高职英语教学现状的分析,在舾装专业教学改革的基础上,提出高职英语教学要围绕学生未来工作岗位设置教学内容,“以学生为中心”开展课堂教学,并且加大学习过程的考核,激发学生学习英语的积极性与主动性,使学生在仿真工作环境中提高英语应用能力 相似文献
997.
吴旺山 《广东交通职业技术学院学报》2013,12(2):43-45
船舶海水冷却系统中,如果海生物大量繁殖将导致船舶海水冷却系统管路有效流通面积减少,严重时甚至造成管系堵塞,导致船舶动力装备冷却不良,工况恶化。文中从某轮海水冷却系统防海生物装置的原理出发,结合船舶营运过程中海生物防止装置运行的特点,以船舶海生物防止装置的工作原理为依据,总结了船舶海水冷却管系海生物防止装置的管理维护要点,保证船舶海水冷却水系统免受海生物的污染,从而确保船舶冷却海水系统运行工况良好。 相似文献
998.
Simon Robertson 《运输规划与技术》2013,36(5):395-412
Abstract This paper quantifies and evaluates, utilising a ‘bottom-up’ approach, the effect on CO2 emissions of a modal shift from short-haul air travel to high-speed rail (HSR), based on projected passenger movements, between Sydney and Melbourne, Australia during the period 2010–2030. To date, peer-reviewed studies assessing the CO2 emissions from these competing modes of high-speed transportation have been restricted principally to a cross-sectional assessment, with a Eurocentric bias. This present comparative study seeks to address a gap in the literature by assessing, longitudinally, the CO2 emissions associated with the proposed operation of HSR against the ‘business-as-usual’ air scenario between Sydney and Melbourne. Under the assumed 50/50 modal shift, and the Australian government's current renewable electricity target, an annual reduction in CO2 emissions of approximately 14% could be achieved when compared with a ‘business-as-usual’ air scenario. This percentage reduction represents a 62 kt reduction in base year, 2010, and a 114 kt reduction in the final year, 2030. In total, the overall reduction achieved by such a modal shift, under the assumed conditions, during the period 2010–2030, equates to approximately 1.87 Mt of CO2. Importantly, if the electrical energy supply for HSR operations was further ‘decarbonised’, then it follows that a greater emission reduction would be achieved. 相似文献
999.
This study investigates the impacts of transit improvement strategies on bus emissions along a busy corridor in Montreal, Canada. The local transit provider, Société de Transport de Montréal, has implemented a number of strategies which include the use of smart cards, limited-stop (express bus) service, and reserved bus lanes along this corridor. Using data collected on-board for instantaneous speeds and stop-level ridership, we estimated bus emissions of greenhouse gases and other pollutants at three levels: road segment, bus-stop, and per passenger. A regression of segment-level emissions against a number of explanatory variables reveals that reserved bus lanes and express bus service reduce emissions significantly. On the other hand, smart card use reduces idling emissions compared to other fare payment methods. Our findings are of most relevance for transit planners who are seeking to implement different strategies to reduce emissions and improve transit performance. 相似文献
1000.
The prediction of a ship's resistance especially the viscous wave-making resistance is an important issue in CFD applications. In this paper, the resistances of six ships from hull 1 to hull 6 with different hull forms advancing in still water are numerically studied using the solver naoe-FOAM-SJTU, which was developed based on the open source code package OpenFOAM. Different components of the resistances are computed and compared while considering two speed conditions(12 kn and 16 kn). The resistance of hull 3 is the smallest while that of hull 5 is the largest at the same speed. The results show hull 3 is a good reference for the design of similar ships, which can provide some valuable guidelines for hull form optimization. 相似文献