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891.
This study focuses on China's coastal area and its marine economic development. Applying the information diffusion method, the study establishes a kernel density function and its decomposition using a marine economic per capita as the index of the model to depict the dynamic evolution law and the internal influential factors of the Chinese marine economy during 1996–2013. The relative development rate was introduced to analyze the spatial differences in the marine economy's development. In this way, space and time dimensions fully characterized the evolution of the Chinese marine economy. Additionally, the influence of growth and inequality in the process of its development can be analyzed. The study shows that the Chinese marine economy as a whole has been growing, and regional marine economic development is relatively coordinated. In addition, the marine economy began to develop even more rapidly after 2004. There are three factors affecting the dynamic evolution of China's marine economy: first, the most influential mean effect, followed by, second, the variance effect, and third, the least influential residual effect. The biggest influence on the dynamic evolution of the marine economy is the improvement of the development level of the marine economy in the coastal area. Meanwhile, due to the existence of inequality, provinces at higher development levels are more dispersed. Furthermore, the existence of the residual effect weakens the influence of the mean effect, and the influence on the dynamic evolution of the marine economy continuously increases. In the analysis of the influencing factors of the evolution and spatial difference of marine economic development, the level of opening to the outside world, the level of investment in fixed assets and the industrial structure have a positive role in promoting economic development. However, capital investment in scientific human research has a negative correlation with economic development, and does not pass the significant test. The difference in regional development levels and development speed is also very apparent; namely, the provinces with higher development levels generally displayed faster development speeds while those with lower development levels showed slower development speeds across the four periods analyzed.  相似文献   
892.
The interactions of cnoidal waves with a submerged quartercircular breakwater are investigated by a Reynolds-Averaged Navier–Stokes (RANS) flow solver with a Volume of Fluid (VOF) surface capturing scheme (RANS-VOF) model. The vertical variation of the instantaneous velocity indicates that flow separation occurs at the boundary layer near the breakwater. The temporal evolution of the velocity and vorticity fields demonstrates vortex generation and shedding around the submerged quartercircular breakwater due to the flow separation. An empirical relationship between the vortex intensity and a few hydrodynamic parameters is proposed based on parametric analysis. In addition, the instantaneous and time-averaged vorticity fields reveal a pair of vortices of opposite signs at the breakwater which are expected to have significant effect on sediment entrainment, suspension, and transportation, therefore, scour on the leeside of the breakwater.  相似文献   
893.
在试验水池中,开展了波浪在岛礁地形上演化问题的研究。首先在实验水池中建立了西太平洋某岛礁地形的模型,然后采用改进的JONSWAP谱,由造波机产生不同周期、波高的随机波浪。试验中观察到了不同类型畸形波生成的过程及不同波面形态的畸形波。对偏度、峰度及水深与畸形波要素Hm/HsHm表示波列中的最大波高, Hs为有效波高)的关系进行了详细的分析,同时,对畸形波波高Hfr与偏度的关也进行了分析。通过对试验结果分析,发现峰度与畸形波要素i>Hm/Hs呈正相关, Hfr增大时相应的偏度也会呈现增大的趋势。此外,水深的变化剧烈时(如斜坡、海山位置)有助于畸形波的发生。  相似文献   
894.
In order to explore the standing stock and preservation of organic carbon, different forms of compound specific lipids were analyzed, based on a 1.8 m sediment core collected in the northern continental shelf of South China Sea in May, 2016. In the core sediments, 21 species of fatty acids, 6 species of alcohols, 8 species of sterols and phytol were detected. Fatty acids were dominated components with the percent of 67%–91% in the total lipids, in which saturated fatty acid C16:0 accounted for about 50%. The contents of lipid species generally decreased from the sediments at surface to those deep, except alcohols waving in a certain range at the same time. Fatty acids primarily existed in free form, followed by base hydrolytic form, and then acid hydrolytic form. Free alcohols were obviously dominated, while base and acid hydrolytic forms contributed small comparably. Phytol gave a significant priority to base hydrolytic form, while acid hydrolytic form could be neglected. Similar to phytol, sterols mostly presented in base hydrolytic form, and then in free form. The compositions of lipids and their forms suggested that organic carbon basically originated from primary production in upper waters in studying area, and were well preserved in the sediments.  相似文献   
895.
本文使用塔基直接观测法研究海洋大气边界层中的海-气界面动量通量。首先,我们收集数据并和前人观测结果比对,其比对结果符合一致。其次,在低风速至中等风速条件下,我们发现海-气界面动量通量的交换系数(又称拖曳系数)对于向岸风和离岸风两种情形有所差异。为此,我们使用一个考虑表面波的参数化方案解释海-气界面动量通量对于表面波的依赖关系。这些结果一方面证实表面波对于海-气界面动量通量的影响,另一方面验证一个考虑表面波参数化方案的有效性。  相似文献   
896.
Many typhoons pass through the East China Sea(ECS) and the oceanic responses to typhoons on the ECS shelf are very energetic. However, these responses are not well studied because of the complicated background oceanic environment. The sea surface temperature(SST) response to a severe Typhoon Rananim in August 2004 on the ECS shelf was observed by the merged cloud-penetrating microwave and infrared SST data. The observed SST response shows an extensive SST cooling with a maximum cooling of 3°C on the ECS shelf and the SST cooling lags the typhoon by about one day. A numerical model is designed to simulate the oceanic responses to Rananim.The numerical model reasonably simulates the observed SST response and thereby provides a more comprehensive investigation on the oceanic temperature and current responses. The simulation shows that Rananim deepens the ocean mix layer by more than 10 m on the ECS shelf and causes a cooling in the whole mixed layer. Both upwelling and entrainment are responsible for the cooling. Rananim significantly deforms the background Taiwan Warm Current on the ECS shelf and generates strong Ekman current at the surface. After the typhoon disappears, the surface current rotates clockwise and vertically, the current is featured by near inertial oscillation with upward propagating phase.  相似文献   
897.
大地震专题信息系统(Significant Events Information System,SEIS)是一个针对单个大地震的综合性专题信息管理软件.通过其数据存储子系统保存数据,通过其数据管理子系统处理和管理数据,通过其数据服务子系统提供数据.较之国内外同类软件,具有信息的集成性、资料的区域性和数据的实用性等主要特点.随着SEIS系统在实际工作中的全面应用,大地震专题信息数据逐步实现了存储的规模化、管理的科学化与自动化以及服务的多样化,并积累了丰富的资料,提高了数据服务的质量.  相似文献   
898.
南黄海辐射沙洲西太阳沙海域钻孔沉积环境分析   总被引:4,自引:1,他引:3  
南黄海辐射沙洲枢纽区的西太阳沙海域钻孔岩芯很好地揭示了研究区全新世中晚期潮成沙脊沉积序列和晚更新世末期滨岸潮滩沉积序列.潮成沙脊在垂向上由两个基本的沉积相构成:出现在-5m水深以上的沙脊-浅潮下相以发育小型沙波交错层理、水平层理、块状层理和缺乏生物扰动为特点; 发育在水深 -5m以下的沙脊-深潮下相以出现脉状层理、波状层理和沙波交错层理组合为特点,具有丰富的生物扰动,并保存有风暴沉积.14C测年数据表明潮成沙脊是中全新世以后形成的,在辐射沙脊群形成之前,研究区经历了晚更新世的滨岸潮滩环境以及早全新世的海侵环境.烂沙洋靠西太阳沙一侧潮流通道目前已切入晚更新世滨岸潮滩相地层,潮道底部约8m厚的淤积层夹有强烈变形的滑塌堆积,可能与台风、风暴潮引起的骤然淤积有关,目前已被1992~2003年的海图资料证实.  相似文献   
899.
采用暴雨站数预报与站点降水量预报相结合的方法预报暴雨落点,在1998年7~8月的暴雨落点预报中,TS评分达到22.4%,超过了HLAFS和主观预报。进一步的研究分析表明:这种方法可充分利用降水量预报的空间分布信息,预报准确率还存在较大的可提高空间,是一种较为有效的暴雨落点客观预报方法  相似文献   
900.
中国数字地震台网(CDSN)的现状   总被引:2,自引:0,他引:2  
介绍了中国数字地震台网数据处理中心计算机系统的硬件软件配置和台网的数据处理及生成的地震数据。  相似文献   
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