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101.
T. N. Krishnamurti John Molinari Hua-Lu Pan Vince Wong 《Pure and Applied Geophysics》1977,115(5-6):1357-1372
In this short paper we have identified some of the modelling groups that have the capability of simulating or carrying out short range numerical weather prediction over the monsoon belt. We have next outlined some of the important and desirable ingredients for a multilevel primitive equation model over the tropics, with most of the emphasis on the present version of Florida State University's Tropical Prediction Model. Finally, we present briefly some important results based on the present version of our prediction models that relate to the NWP efforts over the monsoon belt. Here we have identified the importance of mountains, convection, the radiative heating balance of the earth's surface, and the planetary boundary layer over the Arabian Sea. 相似文献
102.
We investigate the estimation of interfacial areas, curvatures, and common curve lengths in multiphase porous medium systems. Algorithms are developed to obtain estimates of these quantities based upon a variety of potential data sources and estimation approaches. The accuracy of the derived approximations are evaluated as a function of the data type and resolution of the data. The methods advanced improve upon standard approaches now in use and show excellent accuracy at resolutions on the order of five lattice points per minimum radius of curvature of the object being resolved. Finally, we suggest a promising class of extensions that could lead to further improvements in the accuracy of such methods. 相似文献
103.
Twenty broadband seismographs were deployed along Hongyuan, Sichuan to Wuwei, Gansu. 81 teleseismic events were recorded in one year. We computed receiver functions from teleseismic waveform data and obtained S wave velocity structure beneath each station along the profile by using receiver function inversion method. The results revealed that the crustal structure is very complex and crustal average S wave velocity is to be on the low side. Low velocity structure generally exists in the depth range of 10~40 km in the crust between Aba arc fault and northern edge fault of Qinling earth's axis and it is a tectonic feature of complex geological process such as ancient A'nyemaqen Tethys ocean from closing and side colliding to subducted plate exhumed or thrust rock slice lifted. The Moho is about 50 km depth along the profile and is slightly deeper in the south than in the north. 相似文献
104.
西宁地震台FHD数字化核旋仪从2006年10月安装以来,一直与模拟仪器并行工作。二者采样率不同,所测的量也不相同。在对西宁地震台磁变仪的记录图纸进行数字化转换、生成分钟值的基础上,对FHD仪和磁变仪的观测结果进行对比分析。结果表明:数字FHD仪比三分量磁变仪更加准确地记录了当地地磁场的变化,数字仪器的观测资料明显优于模拟仪器。 相似文献
105.
安徽省震中快速定位查询系统 总被引:1,自引:0,他引:1
基于VB6.0软件开发平台,以MapInfo GIS软件为数据支撑平台,建立了安徽省震中快速定位查询系统。系统主要实现了震中快速定位查询显示功能、基于GIS数据的空间分析和定量计算分析功能。为地震应急响应提供辅助决策,为震后资源调度、伤员输送、人员疏散等提供科学信息,提高了应急救援的效率。 相似文献
106.
107.
Impacts of domestic sewage effluent on phytoplankton from Bedford Basin, eastern Canada 总被引:2,自引:0,他引:2
The impact of domestic sewage effluent (SE) on the dynamics of phytoplankton assemblages from Bedford Basin was evaluated in the laboratory. Phytoplankton production and chlorophyll a increased proportionally with SE enrichment. Phytoplankton species composition also changed. The potentially harmful diatoms, Pseudonitzschia spp., present initially in small numbers (600 cells 1−1) in Bedford Basin seawater, and became dominant (3–5×106 cells 1−1) when the seawater was enriched with 0.5–5% untreated SE. With higher proportions of SE, other harmful species such as Fragilaria spp. and Euglena spp. became dominant (7−15×106 and 2.2×104 cells 1−1, respectively). Treatment of SE with UV light or activated charcoal seems to favour growth of benign species, such as Chaetoceros socialis, Skeletonema costatum and Thalassiosira spp., but not harmful species such as Pseudonitzschia spp. Further research on UV treatment of domestic sewage is recommended. 相似文献
108.
Hongchun Wang Ping Jin Changzhou Pan Weiguo Xiao Northwest Institute of Nuclear Technology Xi'an China 《地震学报(英文版)》2009,(1):13-20
The relative amplitude method(RAM) is more suitable for source inversion of low magnitude earthquakes because it avoids the modeling of short-period waveforms.We introduced an improved relative amplitude method(IRAM) which is more robust in practical cases.The IRAM uses a certain function to quantify the fitness between the observed and the predicted relative amplitudes among direct P wave,surface reflected pP and sP waves for a given focal mechanism.Using the IRAM,we got the fault-plane solutions of two ea... 相似文献
109.
利用核磁共振(NuclearMagneticResonance缩写为NMR)技术探查地下水仅有二十多年的历史,文中简要介绍了NMR找水方法的发展状况,原理和方法特点,重点介绍了中国地质大学(武汉)利用NMR找水方法在中国一些地区找水取得的成效,最后指出了NMR找水方法的发展趋势。 相似文献
110.
时间项分析法中,应用广义最小二乘法进行反演,对长白山天池火山区岩浆系统的长白—敦化(L1)剖面的Pg波到时进行了计算处理,得到了Pg波时间项及基底速度值;取上部地壳的介质平均速度为4.5km/s,经反演求得了各点的深度值,给出了长白山天池火山区结晶基底的厚度分布。结晶基底厚度一般在2.0km左右,而在长白山天池下方结晶基底最厚处接近4.0km;在万宝和敦化附近各有一不太明显的凹陷,其原因可能与在这两个位置处有几条断裂穿过有关。 相似文献