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41.
林则徐是中国近代进步的思想家和伟大的爱国主义者,同时他也是一位虔诚的有神论者.他领导的轰轰烈烈的虎门销烟在中国历史上留下了光辉的一页,也为我们留下了不朽名篇《祭海神文》,向世界宣告了中国禁烟和拒毒的决心.  相似文献   
42.
随着罗津港使用权的获取,自罗津港出入的中国船舶将不断增多,因此对日本海西部的气象保障服务需求势必不断增加。为加强日本海西部海事气象保障服务水平,使其能够为罗津港附近海域在海运、港口管理和海上作业等方面更好地起到规避风险、提高效益的作用,文中根据对目前日本海西部海事气象保障服务现状的调研结果,指出了当前日本海西部海事气象保障服务存在着区域划分不合理、精细化程度不足以及服务形式过于单一等问题。据此,结合目前国内外海事气象保障服务的思路,提出了针对于日本海西部的海事气象保障服务的建议,可为提升日本海西部海事气象保障服务的升级换代提供一些参考思路。  相似文献   
43.
    
Despite European Union (EU) political support to identify the most feasible Motorways of the Sea, the final decision can only be made by Private Shipping Companies, which are operators of a unique stretch of the intermodal chain. This paper provides a multi-criteria decision method to identify the most suitable Motorways of the Sea taking into account the competitiveness of whole intermodal routes versus the alternative of road transport from the loader’s perspective. The analysis is carried out assuming a ‘many-to-many’ transport model. Firstly indexes of time and cost were defined and evaluated for every available route in the model in accordance with a multi-criteria decision matrix. Secondly, through a Monte Carlo simulation a sensitivity analysis was carried out in order to evaluate the influence on the results of the forecast assumed to construct the matrix. The results obtained are not only quantitative, but also qualitative. The development of intermodal routes via Motorways of the Sea is especially relevant for the peripheral EU countries. Due to the relevance of the freight flow between France and Spain and the congestion of their connections through the Pyrenees, the method proposed was applied to the analysis of this particular case  相似文献   
44.
    
The reliability of an offshore structure is dependent on its response to the extreme wave climate; therefore, an adequate knowledge of the wave climate at a location is a prerequisite during design as well as in marine operations. This study aims to contribute to the knowledge of the extreme wave climate in the Norwegian Sector of the Barents Sea, using wave hindcast datasets from the Norwegian Reanalysis 10 km (NORA10) database for four locations.We have considered three commonly used methods for the estimation of extreme wave heights, that is, the initial distribution method, the peak over threshold method, and the annual maxima method. The parametric bootstrap concept is considered in the estimation of the epistemic uncertainty related to sample size. The estimated 100-year significant wave heights obtained from the three methods differ, and the degree of variability in the estimates varies, depending on the dataset. The epistemic uncertainty due to sample size is wider when considering the annual maxima method.The estimates obtained from the three methods show the importance of considering different methods and their associated uncertainties when estimating extreme wave values for design. While it is difficult to single out the best method among the three, the estimated values give knowledge of the possible range of the extreme significant wave heights at the locations. Generally, the datasets considered in this study suggest that the wave climate is less harsh further north compared to the southern region of the Barents Sea. The datasets do not suggest any temporal trends in the historical significant wave heights at any of the locations.  相似文献   
45.
    
The South China Sea has attained global attention because of terraria disputes over oil, gas, fisheries and other resources in the sea area. Compared with the valuable natural resources, the underwater cultural heritage is not recognized or considered, but is an important legacy of many losses of vessels over centuries. Recently, the surrounding states in the South China Sea have taken measures to preserve underwater cultural heritage in their sea waters. However, the current complicated situation of the South China Sea intensifies the difficulties of protection of underwater cultural heritagein that area. There is an important and interesting potential issue of identification of ownership of underwater cultural heritage because of differences of legislation and claims to jurisdiction. Under the current information of legislation of some states in the South China Sea, it can be understood this issue cannot be avoid on the protection of underwater cultural heritage. This article discusses potential disputes over ownership of underwater cultural heritage in the South China Sea based on the different legislation of several states (China, Vietnam and Philippines) and proposes some possible suggestions for resolving the issue of ownership, rather than performing a primary research.  相似文献   
46.
辛元欧 《中国航海》2000,(2):94-100
本文以古代中朝海上交通为主线,论及华夏文明在朝鲜半岛的传播以及中国古代造船技术对朝鲜的影响.频繁的海上贸易导致黄海两侧中朝港口的繁荣.  相似文献   
47.
    
The existence of trapped modes due to a horizontal submerged rigid cylinder placed below a compressed ice-covered surface is shown to exist within the frequency band of wave blocking by employing linearized water wave theory and with the inclusion of the effects of a two-dimensional current and the obliqueness of the propagating wave. A new modified multipole expansion method catering to the multiple propagating modes is proposed. The impact of different choices of propagating modes at a fixed frequency within the above-mentioned band on the trapped modes is detailed. Multiple trapped modes whose number depends on the direction and magnitude of the current exist within the frequency band. Out of the three choices of current types considered, while two of them result in the generation of trapped modes for all three possible choices of the propagating wave, the remaining one shows that only one propagating mode can generate a trapped wave. A break in the continuous spectrum of the trapped mode frequency due to the wave blocking and at the point of inflexion is presented. There exists a region of angle of propagation within which an abundance of the trapped mode is shown. The surface profiles for different angles of propagation and choices of propagating modes are illustrated graphically. The trapped modes associated with a higher angle of propagation decay at a faster rate.  相似文献   
48.
开山填海场区表层填土粒径不均匀、常伴有大块石,表层以下存在淤泥或淤泥质黏土,这种上硬下软且存在大块石的地层给地基处理带来了很大困难,结合某开山填海场区采用柱锤冲扩桩结合塑料排水板进行地基处理的工程实例,介绍了排水固结与散体挤密桩结合的复合地基处理方案的设计与施工,地基处理取得预期效果的同时,也为开山填海场区的地基处理中提出了一种新的动力排水固结设计理念。  相似文献   
49.
杭州湾跨海大桥南滩涂区承台钢吊箱围堰设计与施工   总被引:3,自引:1,他引:2  
本文介绍了在杭州湾海域风大、流急、冲刷严重、潮差大等特殊的施工环境条件下,根据南岸滩涂区地貌及承台结构设计特点,通过对单壁钢围堰、钢板桩围堰和钢吊箱围堰施工方案的系统分析,说明了钢吊箱围堰施工的经济性,合理性,实用性和安全可靠性。提出了利用装配式砼吊箱底板钻孔桩钢护筒支撑和潮水涨落间隙,进行水中承台钢吊箱围堰的设计与施工技术。  相似文献   
50.
NAPA软件在船舶总体性能设计上的应用   总被引:1,自引:0,他引:1  
秦宇 《广东造船》2010,29(2):34-36
NAPA是一款功能较为完善的船舶三维设计软件,本文通过对150t海监执法船应用NAPA软件进行总体性能设计的介绍,分析了该软件的特点并指出了使用中应注意的某些问题,以及同其他软件的比较等。  相似文献   
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