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21.
While the demand for low-cost air transportation is potentially huge in Asia, development of low-cost carriers (LCCs) lags behind the region's overall aviation development, and certainly lags behind the LCC development in North America and Europe. It has been noted that market conditions and the regulatory environment of Asia are different from those of North America and Europe. What are the main differences here; and how do these differences impact market entry and success of Asian LCCs? This paper describes salient features of Asian LCCs and their developments. It examines the impact of Asia's domestic and international airline regulations and airport infrastructure on the performance of its LCCs. We find that the “Southwest effect” may also exist in Asia and that the development of low-cost terminals may compensate, at least partly, the scarcity of secondary airports in the region. The experiences of Thailand and China are investigated as case studies.  相似文献   
22.
针对目前浙江电煤海上运输需求和现有运煤船运力不足之间的矛盾,提出了新一代散货船开发的目标,新研发的这种船技术性能达到了预期的目标.目前该船型已在多家船厂建造,订造数量达八艘之多,这显示出新一代船型具有良好的效果和发展前景.  相似文献   
23.
本文对液化气船首次到港、装卸作业前、作业期间现场监督检查及装卸作业中和作业完毕的注意事项作了具体介绍,并对此类船舶的安全管理提出了明确的要求。  相似文献   
24.
This study investigates the role of air transport service in the attractiveness of universities to national students, examining how it might stimulate local economic development by attracting highly skilled labor. Examining the flow of Italian university students at the provincial level in 2003–2012, we find that the air transport service affects university attractiveness for long-distance students living at least 300 km from their university. Specifically, accessibility increases with the proximity of universities to airports, when low-cost carriers serve university routes and more alternative airports exist at the origin. Further, our results suggest that, over the last decade, air transport service has facilitated mobility of long-distance students from southern areas to universities in the north of Italy, where students generally move to increase their future prospects.  相似文献   
25.
赵东升  窦钧  刘玉君 《船舶》2019,30(3):47-56
液化天然气和液化石油气需要在低温条件下储存和运输,因此液舱(液罐)材料的耐低温性能和焊接性是保证结构安全的关键。文中以殷瓦钢、5083铝合金和304不锈钢为例,介绍了LNG船与LPG船使用的耐低温材料的种类和物理性能,在此基础上分析了这三种材料的焊接性,总结了殷瓦钢、5083铝合金和304不锈钢的焊接研究进展及发展趋势。  相似文献   
26.
散货船的船体结构强度与安全   总被引:1,自引:0,他引:1  
本文通过对散货船船体结构事故原因的分析和研究,找出散货船从设计到使用存在的内在缺陷,阐述了结构强度对散货船的重要性,提出了船舶管理者在生产实践中应注意的事项和行动准则,旨在为散货船的安全提供一定的理论保障,以减少散货船海事,延长船舶使用寿命。  相似文献   
27.
刘海燕 《世界海运》2003,26(1):24-26
从阐述青岛远洋运输公司管理散装老旧船的具体做法入手,在阐述中总结和提炼管理老旧散装船的方法,从而给同行业人士几点重要启示:一是建立老旧船安全管理体系;二是形成安全管理模式;三是抓住老旧船管理的重点部位,各个击破;四是建立健全规章制度,强化、细化老旧船管理;五是以人为本,全员动员;六是在经营上拓展老旧船生存空间。即对老旧船只要管理得法、到位,老旧船的安全是完全可以有保障的,并且也会产生可观的效益。  相似文献   
28.
The relatively high rates of bulk carrier casualties in recent years, as well as structural features such as large deck openings, make this vessel type a suitable example for investigating the influence of hydroelastic modelling on predicting wave-induced loads and responses. Two- and three-dimensional fluid–flexible structure interaction models, due to their different degree of complexity and associated data requirements, can be used at different stages of the design process when estimating wave-induced loads, namely preliminary and detailed design stages, respectively.

In this paper, therefore, two- and three-dimensional hydroelasticity theories are applied to predict and compare the dynamic behaviour of a bulk carrier hull, based on OBO MV Derbyshire, in waves. Both symmetric and antisymmetric motions and distortions are incorporated in these investigations. The three-dimensional structural model consists entirely of shell finite elements, representing all major external and internal structural components, whilst the two-dimensional model is generated using Timoshenko beam finite element and finite difference discretisations. Issues relevant to the structural modelling stage, for both idealisations, are discussed. The in vacuo dynamic characteristics are compared for all models, with particular emphasis on the influence of hatch openings, shear centre and warping on the antisymmetric dynamics of the structure. For the wet analysis the fluid–flexible structure interaction is carried out using two-dimensional (Timoshenko beam and strip theory) and three-dimensional (beam and shell finite element idealisations combined with potential flow analysis based on pulsating source distribution over the mean wetted surface) analyses. Comparisons are made between steady-state responses predicted by two- and three-dimensional models in bow quartering regular waves.

It is shown that whereas the predicted symmetric dynamic responses obtained from two- and three-dimensional models are in good agreement, differences are observed for the antisymmetric dynamic characteristics. It is thought that this may be due to inadequacies in the beam models employed when simulating the global dynamic behaviour of this highly non-prismatic hull girder whilst allowing for the effects of warping.  相似文献   

29.
Abstract

In this article, a cargo container loading plan model is developed based on the operations of FedEx, the international air express carrier. The objective is to minimize total container handling cost, subject to related operating constraints. The model is expected to be a useful planning tool whereby international air express carriers such as FedEx can decide on container loading plans that will lead to lower operating costs, thus enhancing profits and market competitiveness. The model is formulated as a non-linear mixed integer program that is characterized as NP-hard. A solution method is then developed, with the use of the mathematical programming solver, CPLEX, to solve the problem efficiently. To evaluate the model and the solution method, we perform a case study using data from FedEx. The preliminary results indicate that the model and the solution method are both efficient and effective.  相似文献   
30.
本实验应用~(32)pHBV DNA 探针,从4例慢性携带着尿经200,000×g12小时超迷离心,浓缩100倍处理,检出1例 HBV DNA 阳性,初步证实了携带者尿中排出 HBV DNA,提示 HBV 有可能经携带者尿液传染,为进一步探讨乙肝的传播途径提供新的实验手段。同时亦证明了超速离心浓缩尿液标本进行 HBV DNA检测是可行的。  相似文献   
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