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61.
海权是国家主权的自然延伸,是一种具有权利义务内容的法权;海权是国家在海洋中享有的基本权利,是一种安全权和自卫权;海权还是主权国家的发展权。随着国际海洋新秩序的确立,国际社会应该重新认识和定位海权。我国政府应维护我国的海权,推动我国海洋事业的发展。  相似文献   
62.
关于中国古代"海上丝绸之路"最早始发港研究述评   总被引:4,自引:2,他引:4  
韩湖初  杨士弘 《地理科学》2004,24(6):738-745
通过广东近年有关中国古代海上丝绸之路始发港的研究,得出比较一致的意见是:①番禺(广州)虽是岭南有名的大都会,但并非最早始发港;②中国西汉对外海上贸易和交通中心在北部湾,故其沿海地区的合浦、徐闻和日南(今越南境内)成为海丝路的最早始发港;至吴晋以后海上贸易中心始转移到番禺;③合浦与徐闻同为始发港,但合浦的自然条件更为优越,其地位比徐闻更为重要,汉时也比徐闻繁荣.  相似文献   
63.
发展高端航运服务业是港口城市产业转型的重要着力点。基于劳合社海事企业名录,利用连锁网络、回归模型等,研究1982—2018年全球高端航运服务业节点城市和城际联系的空间演变及影响因素。结果表明:(1)全球高端航运服务业骨架由"T"字型向"大三角形"转变,网络重心不断东移,欧洲、地中海和亚太地区构成的东西向市场是其发展主线。(2)节点城市的网络地位提升与该城市和前序城市建立的联系强度有密切关系,与覆盖的市场范围联系不大。(3)高端航运服务业的区位选择主要受资本、技术和市场的共同影响,其布局临近客户和市场,倾向于知识密集型的产业集聚。(4)集装箱吞吐量和地区宏观经济对高端航运服务业布局的显著性增强,人口数量、港口和行政中心的显著性消失。  相似文献   
64.
柴田  熊德琪 《测绘科学》2013,38(3):137-139
针对目前海上船舶污染风险评估模型的不足,本文提出一种基于船舶自动识别系统(AIS)的海上船舶污染风险定量评估数学模型。该模型的特点是对特定海域船舶污染历史事故进行统计分析,通过AIS中的信息对船舶事故频率进行建模及数值计算;并且模型考虑到事故海域资源类型,船舶种类、大小、风险程度以及污染事故等级等因素,使污染风险评估更科学化和定量化。  相似文献   
65.
康德勇  徐劲  茅永兴 《天文学报》2005,46(3):314-321
将人造卫星精密定轨理论应用于海上移动站精密定轨,根据移动站的特点,建立了相应的定轨条件方程,并在此基础上利用海上移动站某次飞船发射任务跟踪数据进行了实算,给出了定轨结果和讨论。  相似文献   
66.
Stuart Elden 《Geoforum》2009,40(3):407-417
This paper considers the ways in which Iraq’s territorial integrity has been invoked by the international community, how it was violated by the US-led coalition between 2003 and 2007, and how these acts have called into question the future viability of the Iraqi state. The paper contends that Iraq provides an instructive illustration of how the international legal term of territorial integrity is being pulled apart; where the spatial extent of the state must be preserved at all costs, yet the sovereignty of the state is rendered entirely contingent. Using interviews with key actors within the British context and documentary analysis, this paper examines the political situation in Iraq and the content of the new Iraqi constitution, the rise of factionalism within Iraq, and the report of the Iraq Study Group. In doing so it considers the impact of key decisions concerning Iraq’s sovereignty upon the future viability of the state.  相似文献   
67.
Voronoi tessellation, and its dual the Delaunay triangulation, provide a cohesive framework for the study and interpretation of phenomena of geographical space in two and three dimensions. The planar and spherical solutions introduce errors in the positional accuracy of both Voronoi vertices and Voronoi edges due to errors in distance computations and the path connecting two locations with planar lines or great circle arcs instead of geodesics. For most geospatial applications the introduction of the above errors is insignificant or tolerable. However, for applications where the accuracy is of utmost importance, the ellipsoidal model of the Earth must be used. Characteristically, the introduction of any positional error in the delimitation of maritime zones and boundaries results in increased maritime space for one state at the expense of another. This is a situation that may, among others, have a serious impact on the financial activities and the relations of the states concerned. In the context of previous work on maritime delimitation we show that the Voronoi diagram constitutes the ideal solution for the development of an automated methodology addressing the problem in its entirety. Due to lack of a vector methodology for the generation of Voronoi diagram on the ellipsoid, the aforementioned solution was constrained by the accuracy of existing approaches. In order to fill this gap, in this paper we deal with the inherent attributes of the ellipsoidal model of the Earth, e.g. the fact that geodesics are open lines, and we elaborate on a methodology for the generation of the Voronoi diagram on the ellipsoid for a set of points in vector format. The resulting Voronoi diagram consists of vertices with positional accuracy that is only bounded by the user needs and edges that are comprised of geodesics densified with vertices equidistant to their generators. Finally, we present the implementation of the proposed algorithm in the Python programming language and the results of two case studies, one on the formation of closest service areas and one on maritime boundaries delimitation, with the positional accuracy set to 1 cm.  相似文献   
68.
利用ArcGIS转换HPD源数据库中航海物标空间数据   总被引:2,自引:0,他引:2  
李颖  徐进  李家  张安民  卫国兵  杨龙 《测绘科学》2013,38(5):141-142,145
我国海事测绘部门自2008年开始引进CARIS HPD海道产品数据库系统,其空间数据共享转换方法一直是无法解决的难题。本文从CARIS HPD物标源数据库和Shapefile文件数据存储结构入手,详细阐述了CARIS HPD航海物标源数据空间信息获取方法和ArcGIS Shapefile文件生成方式,并提出将物标空间数据从HPD源数据库转换至Shapefile文件的解决方案。  相似文献   
69.
The Maritime Continent(MC) is an important region where the Tropical Pacific and the Indian Ocean interact with each other via "the atmospheric bridge" and a key region for the interaction between the Asian and Australian monsoons. Using the NCEP/NCAR and CMAP monthly mean reanalysis over the period of 1979-2012, the interdecadal variations of diabatic forcing over the key region of the Maritime Continent and its possible relations with the East Asian summer monsoon have been investigated in the present paper. Our results show that climate variations in the Maritime Continent is particularly significant in the area of 95-145°E, 10°S-10°N, which is thus defined as the key area of the MC(i.e., KMC area). Without the input of latent heat release in the atmosphere, distinct interdecadal change of diabatic heating is found to exist from 1979 to 2012; it intensified before 1980 s and peaked in the late 1980 s and weakened after this period. By analyzing each individual component that contributes to the diabatic heating in the KMC area, surface latent heat flux and net long-wave radiation in the atmosphere are found to be the two dominant components. With negative diabatic heating anomalies over KMC, there will be more precipitation on islands and less precipitation over sea, and more rainfall around the equator, which is in correspondence with the convergence center around the equator in the KMC area. Along the meridional-vertical section averaged between 115-120 ° E, the well-defined vertical circulation anomalies are observed with the ascending branches over KMC and the area around 30°N respectively, and the descending branch over the South China Sea. Water vapor transports from the Bay of Bengal and South China Sea to eastern China to benefit the positive precipitation anomalies. The meridional-vertical circulation in East Asia plays a critical role in linking the interdecadal variability of diabatic heating over the KMC and East Asian summer monsoon anomalies.  相似文献   
70.
Conflicts over territory have resulted in innumerable wars and other violent incidents, but the reasons that some territory is more highly valued or volatile than other areas may not be obvious. This paper demonstrates a taxonomy for analyzing international territorial disputes that seeks to capture their tangible and symbolic dimensions and to weigh them as the international community might. Twenty-six territorial disputes, including offshore areas and separatist issues, were examined and scored according to 15 criteria for objective prominence and 7 criteria related to how a country might view the dispute in terms of its national interest. The taxonomy used Saaty’s Analytic Hierarchy Process to identify tangible and intangible properties, measure their interrelations, and produce intermediate and overall ranks. Each dispute was evaluated for prominence by examining intensifying (symbolic) factors, measures of magnitude, and characteristics that retard resolution. The magnitude of a dispute was judged to contribute the most to overall prominence, having twice the weight of the other two factors. The top five disputes in terms of prominence were the Kurdish issue, Kashmir, Tibet, Nagorno-Karabakh, and Xinjiang. The second hierarchy evaluated the disputes from the perspective of an international actor, in this case the United States. When judged by U.S. national interest, the most important factors were the deployment of U.S. forces in the claimant countries and if one of the claimants were a U.S. ally. Finally, the results from the two hierarchies were compared.  相似文献   
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