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新疆数字地震台网地方性震级量规函数的初步研究 总被引：2，自引：1，他引：1
基于2009～2014年新疆测震台网数字地震记录资料,运用震级残差统计方法,选择16269个2.0≤ML≤5.4地震事件,共计获得了179561个单台记录;利用最大地动位移衰减特性方法,选用3.6≤ML≤4.5的746个地震事件作为研究对象,对新疆数字台网地方性震级量规函数进行了研究。将得出的量规函数值进行对比后认为,现阶段使用的量规函数值在0～200km的震中距范围内偏小,导致此范围内台站测定的震级偏小;在200～800km的范围内,测算的震级值较稳定,偏差范围在±0.1的范围内;在400～800km震中距范围内,由最大地动位移衰减特性方法得出的量规函数偏小。由于目前各地震台站使用的地震计仪器响应不准确,造成量规函数偏小的原因有待用计量更加准确的台站仪器响应参数进行验证,以便得到更加精确的新疆台网地方性震级量规函数。 相似文献
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通过会昌台数字与模拟地震记录到的多个地震事件进行对比分析，认为前者在记录带宽、获取更多的地震动物理量、记录波形能力及可操作性等方面具有显著的优势，数字观测完全可以取代模拟观测；对两种记录计算的地震震级进行了对比与统计分析，发现数字记录近震的震级比远震的偏差要大，远震震级可直接与全国地震目录接轨。 相似文献
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以拜城Ms5.4地震为例,研究新疆地震预警系统产出结果的准确率与时效性.通过数据分析研究,与国家台网地震速报结果相比,新疆天山中段重点地震预警区的3个地震事件,初次触发结果震级平均偏差0.3级,震中位置平均偏差9.6 km,报告用时2.0～4.7 s;最终触发结果震级平均偏差0.4级,震中位置平均偏差5.5 km.非重... 相似文献
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云南省区域数字地震遥测台网远震参数测定 总被引：2，自引：1，他引：1
利用云南省区域数字地震遥测台网记录到的资料对远震的定位方法进行了研究。采用“分离变量法”,将震源参数分为发震时间、震中位置和震源深度三类变量,相对独立进行计算,这就减少了Geiger法中,各类变量因不同权重而产生的互相干扰以及因初始解不好引起的迭代不收敛的问题,改善了定位精度。由于大地震的地震波初动清楚,可精确测定初动到时,仅用经过台站高程走时改正和台站综合走时改正后的初动到时即可精确测定零深度时的震中位置。再根据测定的零深度震中位置,查出台网最小到时子台的S波到时S0它与该台的实际S波到时Sh的差可有效判定地震是否深源地震和计算震源深度。为了保持地震震级定义的一致性,采用数字地震仪系统的传递函数(包括幅频特性和相频特性)对实测数字地震记录进行仿真,得到真正的地动速度,再由计算机自动检测定地动速度最大面波振幅并计算震级Ms。 相似文献
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M. N. French R. L. Bras W. F. Krajewski 《Stochastic Environmental Research and Risk Assessment (SERRA)》1992,6(1):27-45
A procedure for short-term rainfall forecasting in real-time is developed and a study of the role of sampling on forecast ability is conducted. Ground level rainfall fields are forecasted using a stochastic space-time rainfall model in state-space form. Updating of the rainfall field in real-time is accomplished using a distributed parameter Kalman filter to optimally combine measurement information and forecast model estimates. The influence of sampling density on forecast accuracy is evaluated using a series of a simulated rainfall events generated with the same stochastic rainfall model. Sampling was conducted at five different network spatial densities. The results quantify the influence of sampling network density on real-time rainfall field forecasting. Statistical analyses of the rainfall field residuals illustrate improvement in one hour lead time forecasts at higher measurement densities. 相似文献
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《地震工程与工程振动(英文版)》2014,(4)
正This journal is established by the Institute of Engineering Mechanics(IEM),China Earthquake Administration,to promote scientific exchange between Chinese and foreign scientists and engineers so as to improve the theory and practice of earthquake hazards mitigation,preparedness,and recovery.To accomplish this purpose,the journal aims to attract a balanced number of papers between Chinese and 相似文献
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George W. Housner 《地震工程与工程振动(英文版)》2008,7(2):I0001-I0001
Destructive earthquakes have caused great damage in China and the United States and collapsing buildings havecaused many deaths and injuries. The field of earthquake engineering studies earthquake hazards, the occurrence ofearthquakes of various magnitudes, the nature of the ground shaking during an earthquake, the vibration of structuresduring earthquakes, the strengthening of existing structures and the design of new structures to be earthquake resistant,and finally, how to cope with earthquake damage and restore a city to normal functioning. Such efforts are in progressin both countries, but unfortunately, the language barrier interferes with the free flow of information between China andthe Untied States. It would be mutually beneficial if some means could be developed to promote the exchangeof information across the Pacific Ocean. This new journal has been established for this purpose and its success willbe an important step in promoting earthquake engineering in China and the United States. 相似文献
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《国际泥沙研究》2014,(4)
正President:Giampaolo Di Silvio,Italy Vice Presidents:Ulrich C.E.Zanke,Germany Zhao-yin Wang,China The World Association for Sedimentation and Erosion Research(WASER),inaugurated on Oct.19,2004,is an independent non-governmental,non-profit organization.The mission of WASER is to promote international co-operation on the study 相似文献
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JianCheng Shi 《中国科学:地球科学(英文版)》2014,57(10):2281-2282
正Global Change includes climate change and other environmental changes caused by the joint interaction among various layers of Earth. From the positive side, global change provides new opportunities to human and other living forms on Earth. In the meantime, it creates tremendous challenges and negative impact. At present, the negative impacts have reached all primary processes of the global ecosystem and every aspect of human society, especially causing degradation of the ecosystem. For instance, intensive deforestation causes decline of biodiversity; global warming causes sea level rise and increases 相似文献
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Dissolved total carbohydrates (DTCH), dissolved free monosaccharides (DFMS), dissolved organic carbon (DOC), biodegradable DOC (BDOC), and humic substances (HS) were measured in White Clay Creek (WCC), a stream in southeastern Pennsylvania Piedmont, USA. Samples were collected over different seasons and under baseflow and stormflow conditions. DOC concentrations ranged from 1.0 to 12.8 mg/L C with the highest concentrations associated with stormflows. Carbohydrates ranged from 0.42 to 12.4 μM and accounted for 2.9 to 12.7% of the DOC. Humic substances represented the major DOC fraction, accounting for 55 to 72% of the DOC pool under all flow conditions. The humic fraction had a lower carbohydrate content (4.4%) than the non-humic fraction of DOC (7.2%). Stormflow DOC was enriched in carbohydrates relative to baseflow DOC, but the percentage of humic-C changed little. Carbohydrates were primarily present as dissolved polysaccharides (55%), but a significant fraction was bound to humic substances (40%), while a small proportion was present as monosaccharides (5%). The major monosaccharides in stream water, listed in order of decreasing concentration, included glucose, galactose, rhamnose, xylose, arabinose, mannose, and fucose. On average (30.6 ± 7.4)% (n = 44) of the stream water DOC was biodegradable, and carbohydrates accounted for 9.9 to 17.7% of the BDOC. 相似文献