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141.
Analysis on small-earthquake composite fault plane solutions from 1961 to 1999 in Xinfengjiang reservoir area 总被引:2,自引:0,他引:2
Introduction XFJ reservoir has been about 40 years since its water loading in 1959 and has induced a great number of earthquakes. The largest one was the M = 6.1 earthquake occurred on March 19, 1962. Since then, a large amount of seismologists in our country have made many researches on the in-duced earthquake. In the paper, we have studied XFJ reservoir earthquakes and their relation with water cyclic fluctuation by using the mechanism solutions of small earthquakes occurred in these 40 y… 相似文献
142.
Introduction In recent years some big cities in China commonly build subways in central urban areas to improve crowded surface transportation, and the subways usually are large-scale group cavities composed by two parallel cavities. Construction of large-scale group cavities will certainly affect the design ground motion near the cavities, and further affect seismic safety of the existing build-ings nearby. So it is of significance to estimate this effect on seismic design of the buildings. H… 相似文献
143.
Introduction Offshore platform is the main facility for exploitation of ocean resources, e.g. oil and gas. Nearly 6 000 platforms have been built in the world, 100 among them in China, another 100 will be erected in China in the coming 5 years. The current aseismic design code commonly used in the world is RP2A-WSD based on the seismic hazard zone in the coastal waters of the United States, which is compiled by American Petroleum Institute (American Petroleum Institute, 2002). No specif… 相似文献
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145.
Christian B. Eckardt Lynne Dyas Peter W. Yendle Geoffrey Eglinton 《Organic Geochemistry》1988,13(4-6)
A novel method for handling and presenting multimolecular abundance data, derived from gas chromatographic-mass spectrometric analyses (GC-MS), is introduced. The method facilitates carbon number labeling of compounds, specifically in the case of porphyrins, by means of a porphyrin-index, which is part of a novel identification code for porphyrins. Identification code, relative abundance and structure information of each compound recognised are stored in a database, which affords a variety of characteristic displays and tables upon manipulation. The combined facilities allow the direct comparison of samples of different origin, maturity and/or palaeoenvironment. Correlation studies, such as oil/oil or oil/source rock, are also facilitated by comparison of characteristic “fingerprint” histogram patterns. The ability of the method is exemplified through analysis of the porphyrin distributions of Boscan oil, La Luna shale, Gilsonite bitumen and Serpiano shale. 相似文献
146.
147.
GPS载波相位平滑伪距精度分析与应用探讨 总被引:5,自引:2,他引:5
分析了载波相位平滑伪距在动态短基线解算、精密单点定位、动态长基线解算的精度,提出了载波相位平滑伪距在多种高精度定位中的应用。 相似文献
148.
场地类别划分与抗震设计反应谱的讨论 总被引:10,自引:1,他引:10
介绍了新的抗震设计规范(2001—07—20发布,2002—01—01实施)中场地类别划分和地震影响系数的有关内容,指出其中一些不相协调之处。最后,针对不同的问题建议相应的解决办法。 相似文献
149.
通过在格雷码遗传算法进化过程中加入单纯形搜索算子,并利用格雷码遗传算法和单纯形法所得到的优秀个体群,作为变量新的变化范围,逐步缩小搜索空间,自动向最优解收缩,提出了水环境模型参数识别的一种新方法——格雷码混合加速遗传算法(GCHAGA),给出了实施该算法的详细步骤。对GCHAGA的收敛性和全局优化性进行了理论和实例分析,并在确定河流横向扩散系数等参数识别问题中,GCHAGA得到了精度较高的全局最优解。与格雷码遗传算法(GCGA)和常规优化方法相比,GCHAGA具有精度高、速度快和适用性强等特点,是一种既可以较大概率搜索全局最优解,又能进行局部细致搜索的较好的非线性优化方法,可广泛应用于各种水环境优化问题中。 相似文献
150.
Introduction The Tengchong volcanic-geothermal area is located on the northeast edge of the collision zone between Indian and Eurasian plates, and belongs to Eurasian volcanic zone (the MediterraneanHimalayanSoutheast Asia volcanic zone). In Tengchong area, the Quaternary volcanic, geothermal and seismic activities are all intensive. These phenomena have been drawing the attention of many geoscientists in the world. Their studies are concerned with geology, geophysics, geochemistry, and cr… 相似文献