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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
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船冰碰撞载荷下船舶结构加强方案研究 总被引:5,自引:0,他引:5
为了探究水介质对船—冰碰撞结构响应的影响,文章首次对考虑水介质中的船—冰碰撞问题进行了研究。模拟了船舶与冰体在水介质中的碰撞场景,研究船—水—冰三者共同耦合作用对船—冰碰撞的影响。将该计算方法应用于船—冰碰撞的多种工况计算,对比分析了增加外板厚度、横隔板厚度以及肋骨间距等多种加强方案对船体结构响应的差异。揭示了碰撞区域的损伤变形、碰撞力、结构吸能随外板厚度、横隔板厚度和肋骨间距的变化而变化的规律,分析了船舶肩部各主要构件对于抵抗冰载荷作用的能力及贡献。所得结论对于进行冰区船舶结构设计具有参考作用。 相似文献
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The unsteady performance of drag and double reverse propeller podded propulsors in open water was numerically simulated using a computational fluid dynamics (CFD) method. A moving mesh method was used to more realistically simulate propulsor working conditions, and the thrust, torque, and lateral force coefficients of both propulsors were compared and analyzed. Forces acting on different parts of the propulsors along with the flow field distribution of steady and unsteady results at different advance coefficients were compared. Moreover, the change of the lateral force and the difference between the abovementioned two methods were mainly analyzed. It was shown that the thrust and torque results of both methods were similar, with the lateral force results having the highest deviation 相似文献
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