海洋环境污染生物修复技术研究

全球范围内的海洋生态环境恶化,不仅危及海洋经济发展,而且已影响到了人类生存环境和健康。本文根据我国近海海洋环境质量现状,探讨了生物修复技术在海洋环境污染治理中的应用,并提出了工程海藻培育技术研究的有关建议,以期为海洋环境的保护及资源的可持续开发提供新的方法和技术。     

海底双层管单层连接管道结构受力分析

粘性高的海洋石油通常需要通过海底保温管道加温输送.温度变化会引起管道变形,并在管壁内产生较大的温度应力.同时,管道正常运营期间还受到管道内压、外压、管内流体粘滞力和土体摩擦力等环境荷载的作用.复杂的环境可能导致海底管道轴向应力过大发生破坏.为了提高铺管效率,提出了双层管单层连接管道这一特殊管道形式,并从理论上分析温度变化和环境荷载对该管道的影响,计算正常运行时管道不同位置处横截面内最大Von-Mises应力.最后得到了Von-Mises应力沿管道轴线分布情况,发现内管和单层连接管的应力一般比外管大,变径管和内管的焊缝处是Von-Mises应力最大的地方.     

3S技术在堰塞湖应急治理中的应用研究

以四川堰塞湖为例,首先阐述了3S技术的特点、项目实施基本指标和项目作业技术系统;其次重点叙述了3S技术在项目实施中的技术流程,包括资料收集、地形图矢量化、矢量数据空间分析、TM遥感影像处理、野外调查建立解译标志、遥感解译、土壤侵蚀强度计算、解译成果野外校核、数据库集成等步骤.最后列举了如何利用3S技术解决危情作出的贡献.     

东海陆架两期沙脊的时空对比东海陆架两期沙脊的时空对比

基于高分辨率的单道地震和多波束测深数据,识别并对比了东海陆架中部同一海区相距20余万年的层U14和层U2两期沙脊群,其中层U14期沙脊属于埋藏沙脊,位于东海海底以下90 m深处,推测属于距今320~200 ka的海侵体系域(TST),沙脊顶界面是该期海侵的最大洪泛面(MFS);层U2期沙脊位于东海陆架,属于衰退沙脊,系末次盛冰期(LGM)以来的TST,顶界面是LGM以来的MFS。尽管两期沙脊形成年代相距20余万年,地层层位相距近90 m,但是沙脊群总体走向一致,表明距今2×105 a以来东海陆架潮波基本格局稳定。从层U2期可识别出4个亚期沙脊,通过多波束海底地形图可识别出4组走向的沙脊,多亚期、多走向沙脊是LGM以来海平面阶梯状波动在海底地形演变过程中的响应证据。     

Elastic-plastic analysis for pile-anchor supporting system of deep foundation pit

By using numerical analysis methods to simulate the deep excavation, a lot of analyses are established on the basis of two-dimensional plane strain, ignoring the fact that foundation pit possesses three dimensions. For soil constitutive relation, people always take linear and nonlinear model, without considering the plastic behavior of soil. Using plastic-elastic hardening model to simulate constitutive relation of soil characteristics, the authors carried out mechanical analysis for pit excavation and support. The results show that the analysis for the stress state of pile anchor system is an effective way which provides theoretical basis for calculation of soil displacement.     

Modeling Arctic Ocean heat transport and warming episodes in the 20th century caused by the intruding Atlantic Water

This study investigates the Arctic Ocean warming episodes in the 20th century using both a high-resolution coupled global climate model and historical observations. The model, with no flux adjustment, reproduces well the Atlantic Water core temperature （AWCT） in the Arctic Ocean and shows that four largest decadalscale warming episodes occurred in the 1930s, 70s, 80s, and 90s, in agreement with the hydrographic observational data. The difference is that there was no pre-warming prior to the 1930s episode, while there were two pre-warming episodes in the 1970s and 80s prior to the 1990s, leading the 1990s into the largest and prolonged warming in the 20th century. Over the last century, the simulated heat transport via Fram Strait and the Barents Sea was estimated to be, on average, 31.32 TW and 14.82 TW, respectively, while the Bering Strait also provides 15.94 TW heat into the west- ern Arctic Ocean. Heat transport into the Arctic Ocean by the Atlantic Water via Fram Strait and the Barents Sea correlates significantly with AWCT （ C = 0.75 ） at 0- lag. The modeled North Atlantic Oscillation （NAO） index has a significant correlation with the heat transport （ C = 0.37 ）. The observed AWCT has a significant correlation with both the modeled AWCT （ C =0.49） and the heat transport （ C =0.41 ）. However, the modeled NAO index does not significantly correlate with either the observed AWCT （ C = 0.03 ） or modeled AWCT （ C = 0.16 ） at a zero-lag, indicating that the Arctic climate system is far more complex than expected.     

a′Trous小波变换与PCA变换相结合的遥感影像融合分析

随着高分辨率遥感卫星的产生,传统的融合技术难以达到较好的融合效果,如主成分分析(PrincipalComponents Analysis)变换融合受到融合区域的限制,而传统的小波融合(Wavelet Transformation)算法由于高频直接替换,导致了一定程度的光谱失真,由此本文在分析主成分分析变换和a′Trous小波变换(WT)的基础上,以QuickBird全色和多光谱数据为实验数据,提出了一种将两者相结合的遥感影像融合方法,通过与其他融合方法的定量和视觉比较,结果表明该方法能得到更好的融合效果。     

传统海图和电子海图一体化数据模型的构建与应用研究

针对国内在一定时期内既要生产传统纸质海图保证传统导航,又要生产电子海图满足电子导航的需求,构建了一个能够包容S-57电子海图和传统海图信息全集的一体化海图数据模型,基于此模型分析了两种数据到一体化数据模型的转换机制,并应用此模型开发原型系统,实现了二者之间的一体化组织和切换显示,为探索传统海图和电子海图的数据融合提供了思路和参考。     

外大陆架划界信息系统中数据交换方法

采用VB.NET作为开发工具,ArcGIS Engine作为开发平台,进行外大陆架划界的数据交换研究,所开发的程序能够实现图元和文件层次的交换。该方法的研究对于我国外大陆架的划界有着非常重要的参考作用。