Correlation of JMA instrumental seismic intensity with strong motion parameters     

Kazi R. Karim  Fumio Yamazaki 《地震工程与结构动力学》2002,31(5):1191-1212

The Japan Meteorological Agency (JMA) seismic intensity (I_JMA) has been used as a measure of strong shaking for many years in Japan, and it necessitates to know the correlation between the JMA seismic intensity and other strong motion indices, e.g. Peak Ground Acceleration (PGA), Peak Ground Velocity (PGV), and Spectrum Intensity (SI). In this study, two strong motion data sets were selected; in which, the first set consists of 879 three‐components non‐liquefied records selected from 13 major earthquake events that occurred in Japan, the United States, and Taiwan, and the second set consists of 17 liquefied records selected from 7 major earthquake events that occurred in Japan and the United States. The JMA seismic intensity and other ground motion indices were calculated using the selected data sets. The relationships between the JMA seismic intensity and PGA, PGV, and SI were then derived performing a two‐stage linear regression analysis. Results from the analysis show that the JMA instrumental seismic intensity shows higher correlation with SI than PGA or PGV, and it shows the highest correlation with the parameters such as the combination of PGA and SI or the product of PGA and SI. The obtained relationships are also compared with the ones obtained by other studies, which may be useful for the disaster management agencies in Japan and deployment of new SI‐sensors that monitor both PGA and SI. Copyright © 2002 John Wiley & Sons, Ltd.  相似文献   

SPOT卫星遥感数字正射影像生产中一些问题的探讨     

徐慧贤 《测绘与空间地理信息》2002,25(3):43-45

遥感数据作为地形数据更新的重要数据源 ,越来越受到人们的青睐。本文通过在SPOT卫星遥感数字正射影像生产中存在的一些问题进行讨论 ,以便对今后的遥感影像生产及相关软件发展提供借鉴 ,并积极探索其它的遥感数据源及影像处理软件。  相似文献   

内核的转速和倾角对ICW与FICN的影响:Mathews理论     

郭俊义  宁津生 《武汉大学学报(信息科学版)》2002,27(2):118-121

研究了内核幌动（ICW）自由内核章动（FICN）。为了给出解析结果，采纳了一个简单地球模型。与以往的研究相比，本文的新结果包括了内核相对地幔的转速和倾角的影响。  相似文献   

Visualization of wave-induced suspension patterns over two-dimensional bedforms   总被引：1，自引：0，他引：1  

Paul V. Villard  Philip D. Osborne 《Sedimentology》2002,49(2):363-378

High spatial and temporal resolution measurements of suspended sand concentration ( c ) over vortex ripples were collected with a three-transducer acoustic backscatter sensor (ABS) array, under irregular `natural' waves in a multidirectional wave basin. These measurements permit two-dimensional visualization of the movement of sediment-laden vortices over an individual vortex ripple under a series of waves. Patterns of sediment motion were tracked through consecutive zero-crossings in the horizontal velocity ( U ) record measured at 0·05 m above the ripple crest elevation. It was possible to trace the advection of individual sediment-laden vortices at the zero-crossings. During 73% of these events, shedding and advection of coherent suspension events occurred before the flow reversal associated with the zero-crossing. This may be caused by the bedforms retarding the near-bed flow inducing the eddy shedding before the zero-crossing. While at maxima in U , secondary suspension events with low c were observed to pass over the ripple crest moving with U measured at 0·05 m. This pattern is attributed to vortex shedding from adjacent bedforms and/or antecedent suspension events. The most energetic events appeared to persist for several wave cycles and reached heights of ≈0·20 m. These suspension events appeared to be more persistent when smaller waves follow larger waves, possibly as a result of weaker reversals in vorticity. Although the events appeared to be vertically coherent in the time series from the individual transducers, it is apparent through visualization that these events are associated with the pairing of antecedent and developing vortices.  相似文献   

利用地倾斜异常跟踪预报1989年巴塘震群始末     

王元海 《四川地震》1993,(1):53-58

本文详细地介绍了四川1989年巴塘6.7级震群发生过程中,地倾斜异常特征,临震三要素的判断及其跟踪预报过程,是一篇对该次震群短临预报工作的概括。  相似文献   

1993年1月27日云南普洱6.3级地震的预测预报     

任义芝  侯维昆 《四川地震》1993,(2):54-58

本文论述了1993年1月27日云南普洱发生6.3级地震前一个多月,攀枝花南山台几套形变观测资料所显示的中、短临前兆异常特征。并较好地对这次地震作了预报,取得了令人满意的效果。  相似文献   

地倾斜面上的几何学探讨     

刘序俨 《内陆地震》1993,7(1):7-11

通过对地倾斜面上任意一点处的几何学进行较全面的研究,给出了地倾斜面上一点处的方位函数、倾斜不变量以及根据非正交组合的地倾斜观测值计算地面倾斜及其方位角的通用公式,对进行地倾斜观测研究具有一定的实践和理论价值。  相似文献   

一种新型的耐水性高分子湿度传感器          下载免费PDF全文

莫天麟  顾庆超  李汝谅 《大气科学》1993,17(3):369-373

我们研制了一种新型的耐水性高分子薄膜湿度传感器,其湿敏材料是由一种基质聚合物和碱金属盐形成的配合物. 测定了这种传感器在不同湿度下的复数阻抗,为测量线路设计中的参数选择提供了必要的依据.用一个RC振荡电路测量了传感器的振荡频率与相对湿度的关系.结果表明,传感器除了具有响应快、滞后小、灵敏度高等优点外,在它遇水汽结露后,返回各相对湿度时其电参量仍几乎不变,即具有极好的耐水性;在20％—90％RH范围内,传感器的振荡频率与相对湿度的关系几乎是线性的.  相似文献   

井下地震仪的软定向     

李留藏 《地震地磁观测与研究》1992,13(4):57-62

本文给出了井下地震仪软定向的原理及一般方法,并具体确定了菏泽台井下地震仪的方位;同时,文章对软定向的误差和精度进行了讨论。  相似文献   

A widespread simultaneous increase of the microearthquake seismicity and minor crustal movements in and around the assumed rupture zone of the Tokai earthquake     

Yukio Fujinawa 《Natural Hazards》1988,1(3):255-276

Data from an extensive routine network and a high-density temporary seismic observation using the ocean bottom seismometer in and around Suruga Bay, Japan, showed that a simultaneous increase of microearthquake seismicity occurred from mid-July 1984 (Ukawa et al., 1988). The area extended over a region of about 60 km (NS) × 80 km (EW), and is nearly included in the assumed fault zone of the presumed Tokai earthquake. The analyses of the bore-hole ground tilt and volumetric strain data revealed that an anomalous small ground tilt and volumetric strain change occurred at the time of the seismic activity with a duration of about a month. Data of geodetic measurements, groundwater, and radon content were examined with the result that many observational items showed small anomalies during that period. The observed crustal movement was compared with that of slip models of the Philippine Sea plate around Suruga Bay, suggesting that some type of episodic aseismic subducting motion occurred and, thus, caused a crustal movement in the overlying continental plate in the very region of the future fault zone.  相似文献