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81.
ABSTRACT

The Mega-ships, the maximum containerships represented by 20,000TEU-class (LOA:400m, Breadth: 60m, Draft: 16m) which are able to transit both the Malacca Strait and the Suez Canal, have emerged in 2013, aiming at lower shipping cost by economy of scale. At the same time, they inevitably increased port calls in a rotation to collect more cargo demand, resulting in the longer transit time than ever before. Taking this trend into account, the authors proposed the quick delivery scenario between East Asia and Northwest Europe by the NSR (Northern Sea Route)/SCR (Suez Canal Route)-combined shipping, of which 4,000 TEU ice-class containership transits the NSR during the summer season and the SCR in the wintertime, based on a year-round scheduled operation. The quick delivery scenario gives the shorter transit time at an affordable shipping cost depending on the NSR navigable season length. However, the quick delivery scenario cannot avoid uncertainties in navigation especially via the NSR in the summer season, due to rough weather, sea ice, low visibility and icing in the icy water section of the NSR. The authors preliminarily concluded that a year-round scheduled operation of the NSR/SCR-combined shipping will be secured, if the practical navigation schedule is appropriately prepared.  相似文献   
82.
民办高校师资队伍、办学条件及学生思想特点等因素制约着民办高校德育工作的顺利开展。而德育工作是民办高校重要而又薄弱的一个环节。为此,本文阐述了民办高校大学生思想呈现的新特点以及民办高校大学生思想现状的成因。就德育工作者队伍的年轻化使民办德育工作变得"务虚"、民办高校德育内容的空泛化使德育工作因脱离现实而被弱化等方面进行了初步的探讨,并提出了一系列解决这些问题的创新思维。  相似文献   
83.
为解决排放控制区下集装箱班轮运输船期设计和燃油补给联合优化问题,分析了多时间窗、多起讫时间和多装卸效率等合作协议条款与船舶航行、装卸及到/离港时间之间的关联性。结合燃油补给港燃油价格差异和折扣因素,以船公司航线服务周总成本最小化为目标,构建排放控制区下船期设计和燃油补给混合整数非线性规划模型,设计线性割线近似的求解方法。以中远海运集团有限公司AWE1航线为例,数值实验验证了模型及其求解方法的适用性和有效性。结果显示:船期设计与燃油补给联合优化可使船公司航线服务周总成本降低7.41%;随着船舶到港时间窗长度的增大,船公司航线服务周总成本及船舶在排放控制区内平均航速均随之降低。研 究表明,上述合作协议条款不仅有助于船公司更为灵活地调整船舶航速和船期,还有利于减少船舶在排放控制区内的温室气体排放。  相似文献   
84.
介绍了动压轴承(轴瓦)失效的4种表面特征及柴油机轴瓦失效的机理,分析了轴瓦自身质量不良对轴瓦失效造成的影响,分析了机油系统出现故障时轴瓦易受到的损伤。分析了柴油机的组装质量对轴瓦失效的影响。分析了内燃机车柴油机违规运用或发生异常时对轴瓦的影响,并提出了相应的预防措施。  相似文献   
85.
瓦锡兰公司自1990年代后期通过在苏尔寿RTA船用低速柴油机上采用TriboPack(减磨技术)以来,取得了良好的活塞运转性能。本文对该减磨技术的主要方法和特点作了较为详细的介绍。  相似文献   
86.
6S管理是现代企业有效的管理方法,把6S管理方法引入高职院校的实训教学中,可以实现企业与学校之间的无缝对接。文章通过创新6S管理在实训教学的应用,不仅提高了实践教学质量,而且培养了学生良好的行为习惯,实现了高职院校培养高技能、高素质人才的培养目标。  相似文献   
87.
编队防空导弹攻击火力分配优化模型   总被引:4,自引:1,他引:3  
魏诗卉 《舰船电子工程》2004,24(3):43-44,69
海上兵力优化分配是编队防空作战中的重要问题。利用对策论和线性规划等理论和方法,研究了编队防空导弹兵力分配问题,建立了舰艇编队防空突击概率模型、编队防空导弹兵力分配优化模型及其解法。给出了一个实例,并用线性规划方法得到了最优混合策略。此方法为舰艇编队防空导弹部署优化提供了一个基本思路。  相似文献   
88.
对主机的缸套裂纹故障进行分析和探讨,以期找出避免类似主机缸套裂纹和穴蚀的故障的有效措施。  相似文献   
89.
There have been significant changes in the nature of shipping services in recent years. These have been most notably in the liner segment, but other parts of the market have not remained static. Technology shifts have been responsible for some of the change, but there have also been developments in institutional structures and managerial approaches. The economic drivers behind the sector, however, remain relatively poorly understood, despite a copious literature on shipping. Managerial economics has tended to put emphasis on the emergence of more sophisticated logistics structures and the role of information to tighten the overall supply chain. Industrial economists have been concerned with technical change and in particular with its interaction with more liberal markets structures. Often tied with this has been interest in the underlying nature of shipping markets (e.g. competitive, monopolistic or contestable) and, depending on the outcome, whether there is price leadership, collusion, predatory behaviour or whatever. Much of this work has been aspatial, treating shipping as any other industry with distance between demand and supply ignored or incorporated in a very simplistic manner. Environmental economists have focused on matters of fuel efficiency and pollution. This paper takes a broad overview of shipping economics in the context of the larger institutional framework within which it operates. It seeks broader analysis within an institutional economics framework, but also highlights some of the problems of achieving this.  相似文献   
90.
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   
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