Application of Numerical Models in Marine Pollution Research in China   总被引：6，自引：0，他引：6  

SU Jilan  Dong Lixian 《Marine pollution bulletin》1999,39(1-12):73-79

Like many countries in the world, China is also facing serious problems of marine pollution in the coastal zone. The prevailing concern is eutrophication of the coastal water due to river inputs and, in some bays, also due to the over-expansion of aquaculture. As part of the marine pollution research activities in China, applications of mathematical models are also widely used, both to understand the present and to project the future. In this paper, selected Chinese works are reviewed, especially with respect to the effort in reducing the errors introduced in the numerical treatment of the water quality equation.  相似文献   

基于标准化残差的相关观测抗差估计模型   总被引：3，自引：0，他引：3  

余学祥  吕伟才 《武汉大学学报(信息科学版)》1999,24(1):07

根据观测误差与解差函数的关系,建立了山标准化残差构造的相关观测抗差估计模型。  相似文献   

青藏高原多年冻土区地温监测结果分析   总被引：6，自引：0，他引：6  

王绍令  赵新民 《冰川冻土》1999,21(4):351-356

Ground temperatures monitored at four observation sites in permafrost regions on the Tibetan Plateau was analyzed. It was found that the ground temperature at the depth of 12～20 m increased 0.2～0.4 K and the permafrost thickness decreased 4～5 m from the base in Xidatan Site from 1975 to 1989; and the ground temperature at the depth of 6～15 m increased 0.2～0.4 K in Kunlun Pass Site from 1982 to 1997. Contrast observations show that a sand cover, 15～20 cm in depth, can result in a ground temperature decrease of 0.1～ 0.2 K in MS66 Site; and a removal of vegetation can result in a ground temperature decrease of some 0.2 K in Hoh Xil Site. The monitor demonstrates that many factors that control permafrost developing have duality, e.g., sand and vegetation are able to increase or decrease the ground temperature. These factors, in conjunction with permafrost behaviour, play different roles under different conditions. Therefore, it is necessary to study, understand and evaluate permafrost and its engineering geological properties taking the viewpoint of dynamic variation.  相似文献   

The mobilization and deposition of mud deposits in a coastal plain estuary     

Jack Blanton  Clark Alexander  Merryl Alber  Gail Kineke   《Limnologica》1999,29(3):293

Muddy sediments with their potential for containing contaminants are commonly deposited and remobilized by tidal currents in estuarine environments. We examined the mobilization and subsequent redeposition of mud in a coastal plain estuary located in the southeastern United States. Time-series data for salinity, suspended sediment concentrations and quality (percent organic matter and pigment concentrations) were obtained over a 13-hour tidal cycle. We found that fast-settling mud particles are found during the highest tidal current speeds. Particle quality analyses suggest that all the material is of similar origin, and that phaeopigment can be used as a tracer of particles in this system. These particles settle onto the bed when current speeds approach slack conditions. We speculate that the quantity of mud mobilized during neap tide is less than during spring tide resulting in an opportunity for the mud to partially consolidate on the bottom and be removed from resuspension. We further speculate that the muddy sediments are mainly derived from fringing marshes in this estuary.  相似文献   

提高763长周期地震仪的抗干扰能力     

吴淑美  谢文杰  王建新 《福建地震》1999,(2)

我台以《提高763地震仪的抗干扰能力》为课题,在基建完成后,对763仪器重新进行安装调试,对仪器的连续线及耦合系统进行了全面的改进处理。投入运行工作两年来,记录效果较好,仪器的抗干扰能力有了较大程度的提高。  相似文献   

计算机2000年问题对地震观测的影响及其预防方法          下载免费PDF全文

王庭选  范五基  王先  巴志萍  张惠芳 《地震工程学报》1999,21(3):343-344

简要分析了计算机２０００ 年问题对地震观测的影响．这些影响主要表现在各种应用软件方面．提出了几种预防方法,除了更换必要的观测仪器之外,还要解决各类软件的２０００ 年问题  相似文献   

川—20地下水综合观测井井下仪器探头相互干扰的现场实验研究     

贾晋康  彭万星 《四川地震》1999,(4):29-33

给出了川- 20 地下水综合观测井井下仪器探头可能存在机械部分相互干扰的现场研究结果。所得结果对于正确区分各种手段今后的异常与干扰具有参考意义。  相似文献   

1998年初北京地区震磁监测   总被引：1，自引：0，他引：1  

詹志佳  高金田  赵从利  张洪利  沈文志 《华南地震》1999,19(4):1-7

为了加强北京地区地震活动性的监视预报,１９９８年１－２月开展了北京测网与临时台相互配合的地磁加强观测。根据压磁理论与地震应磁效应,应用同步差值,图像演化,快谱幅比等多种方法,分析处理了大量地磁资料,研究了地磁时空变化,探讨了可能存在的震磁前兆消息。  相似文献   

打桩对周围建筑物振动影响的研究与实例分析   总被引：5，自引：0，他引：5  

林建生  吴淑美  王源毅  叶传潜  林子健 《地震地磁观测与研究》1999,20(4):24-29

研究了打桩过程中土层质点振动速度的监测方法,打桩振动对周围建筑物影响程度的评价标准,并结合工程实例探讨了有关因素对检测结果的影响,及施工中应采取的相应减振措施。  相似文献   

大坝观测孔有效铅垂空间的确定          下载免费PDF全文

朱永宜 《探矿工程》1999,(5):16-18

导出了根据测斜数据确定观测孔内有效铅垂空间的几何作图方法,介绍了在作图法基础上产生的计算机编程思路,以及控制观测孔施工质量的数学依据。  相似文献