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121.
庆祝中国地震学会成立20周年大会,于1999年12月29日在中国地震局地球物理研究所召开.来自中国科学技术协会、中国地震局、中国地震学会理事会、中国地震学会各专业委员会、中国地震局京区各有关单位、中国地震学会会员单位和各有关全国性学会的代表约250位来宾参加了大会.参加大会的还有中国科学技术协会副主席曾庆存院士、中国地震局局长陈章立同志、中国地震学会理事长陈运泰院士、中国地震学会前任理事长丁国瑜院士、秦馨菱院士、曾融生院士、马宗晋院士、陈颙院士、马瑾院士、许绍燮院士等.中国地震学会秘书长邹其嘉在… 相似文献
122.
人们认识自然总是从实践到理论,再从理论到实践.没有理论指导的实践是盲目的实践,没有实践基础的理论是空洞的理论,只有理论与实践密切结合,才能有所发现,有所进步. 相似文献
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124.
岩性油气藏在我国天然气勘探开发中占有非常重要的位置,其分布区域的成像是合理布设井位,提高钻井成功率的关键之一.本文首先基于地下介质的声学近似和波场回传理论,利用频率域单程声波方程延拓计算地震波场,进行全波形反演,获得地层密度和体积模量的定量成像,并依据油气藏物性特征和流体饱和多孔介质岩石物理模型,简要讨论了孔隙度和饱和度与密度及体积模量的关系,明确了地震油气藏成像新概念.在此基础上,定义了基于流体体积模量和孔隙度的成像函数,进行油气藏成像.理论模型计算表明该方法是可行的.通过对西部地区某气田二维地震数据处理,实现了致密砂岩气藏成像,钻井结果证实了气藏区域成像位置的准确性和方法的有效性. 相似文献
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In this paper, a numerical method for correlation sensitivity analysis of a nonlinear random vibration system is presented. Based on the first passage failure model, the probability perturbation method is employed to determine the statistical characteristics of failure modes and the correlation between them. The sensitivity of correlation between failure modes with respect to random parameters characterizing the uncertainty of the hysteretic loop is discussed. In a numerical example, a two-DOF shear structure with uncertain hysteretic restoring force is considered. The statistical characteristics of response, failure modes and the sensitivity of random hysteretic loop parameters are provided, and also compared with a Monte Carlo simulation. 相似文献
127.
Application of ensemble kalman filter to geophysical parameters retrieval in remote sensing:A case study of kernel-driven BRDF model inversion 总被引:5,自引:0,他引:5
QIN Jun YAN Guangjian LIU Shaomin LIANG Shunlin ZHANG Hao WANG Jindi LI Xiaowen 《中国科学D辑(英文版)》2006,49(6):632-640
Remote sensing can provide multi-spatial resolution, multi-temporal resolution multi-spectral band and multi-angular data for the observation of land surface. At present, one of research focuses is how to make the best of these data to retrieve geophysical parameters in conjunction with their a priori knowledge and simul-taneously consider the influence of data uncertainties on inversion results[1-5]. The essence of remote sensing lies in inversion. It is difficult to precisely retrieve parame… 相似文献
128.
An in-situ experimental program in a jointed rock mass was designed and implemented to investigate the rock joint effects on stress wave propagation. Accelerometers were placed on rock surface along three lines at 0, 45 and 90° to the predominant rock joint strike direction. Eight blasts were detonated in a charge hole drilled in the rock mass. The equivalent TNT blast weight ranged from 2.5 to 50.0 kg and the loading density (charge weight divided by the charge chamber volume) varied from 1 to 20.0 kg/m3. A fully coupled detonation with a charge weight of 25.0 kg was also exploded to study the coupling effect. The recorded data are presented and analyzed in this paper. The effects of rock joints on characteristics of stress wave propagation such as peak value attenuation, spectrum, and spatial variations are discussed. 相似文献
129.
130.
Chen Shun-yun Xu Zhao-yong Yang Run-hai Zhao Jin-ming Hao Jin-qi Wang Yun-yun Xiong Bing-heng Wang Zheng-rong 《地震学报(英文版)》2002,15(6):656-666
Based on the phenomena that the deformation gap was observed before the great Tangshang earthquake, this paper discusses the
strain gap according to test and theory. The (strain) patterns were recorded photographically by realtime holographic interferometry
and shadow optical method of caustics, as soon as the loading process started. In the meantime, the AE (acoustic emission)
signals were recorded by a micro crack information storage-analysis system. According to damage theory and location of micro
fracture, we have studied the stain gap and gained: a) It is necessary that strain gap appears under the condition of linear
elasticity theory, and its situation is relatively stable, corresponding to stress concentration. b) Micro fractures, which
appear initially at area of high stress, occur rarely at the strain gap, and their locations are finally in the zone between
the stress concentration area and the strain gap, which indicate the clusters or groups. However, the major macro fracture
(final rupture) started from the shadow areas, and then grew quickly towards the strain gaps, which resulted in failure of
sample.
Foundation item: The Dual Project of China Seismological Bureau (9691309020301), the Specialized Funds for National Key Basic Study (G1998040704),
the project for the MOST under contract (2001BA601B02) and Youth Funds for applied basic study of the Science and Technology
Bureau of Yunnan Province (98D019Q). 相似文献