关于数字化记录中前兆信号的分析   总被引：1，自引：0，他引：1  

王亮 《地震地磁观测与研究》2005,(Z1)

介绍了如何用MATLAB工具软件—小波分析的基本理论对数字信号进行数字滤波,着重分析和研究了呼和浩特地震台形变观测资料出现各种信号,提出了小波分析理论对台站实际工作的重要性。  相似文献   

A study on the focal parameters of Shidian M =5.9 earthquake sequences in 2001     

Qin Jia-zheng  Qian Xiao-dong  Ye Jian-qing 《地震学报(英文版)》2005,18(3):269-279

On the basis of about 300 earthquake wave forms observed in the Shidian M _S=5.9 sequences on April 12, 2001 recorded in Kunming Digital Seismic Network, the spectra of shear wave have been used to estimate the focal parameters of these earthquake sequences. The results show that within the magnitude range of 1.5–5.3, the seismic moments are 10¹⁰–10¹⁶ N·m, the corner frequencies are 0.2–0.8 Hz, radii of the focal rupture are 200–2 500 m and the stress drops are 0.1×10⁵–20×10⁵Pa. Through the statistical analyses of variation of corner frequency f _c and stress drop Δσ with time, it is discovered that the average corner frequency of the foreshock sequences is obviously lower than that of the aftershock sequences. Contrarily, the average stress drops Δσ of the foreshock sequences are clearly higher than that of the aftershocks. It is considered that these variation characteristics of average corner frequency and stress drops before and after the main shock have index significance to the precursory information before a strong earthquake. The higher stress drops for the foreshock sequences show that the higher shear stresses have been stored in the area of main shock. After the main shock, most of the stresses have been released, so the aftershock sequences show a rupture process of lower stresses. Foundation item: Scientific and Technological Key Project of Yunnan Province (2001NG46)  相似文献   

On the Intensity Virtual Area Characterization in the Intensity Distribution Modelling by Macroseismic Planes     

Domenica Termini  Antonio Teramo  Carla Bottari 《Pure and Applied Geophysics》2005,162(4):699-705

A procedure is proposed for the reconfiguration of the macroseismic planes relative to earthquakes that, being characterized by a reduced number of points of observed intensity due to a lack of information, or having the epicenter very close to the coastline, are characterized by an incomplete distribution of observed intensity levels. The design of a plurality of virtual areas, through which a distribution of intensity consistent with an anisotropic model of attenuation is depicted, allows a reliable determination of macroseismic parameters of the same seismic event.  相似文献   

Macroseismic Intensity Modelling of Earthquakes in Southern Spain: Attenuation and Tectonic Implications     

Tiziana Tuvè  Antonio Teramo  Jesus Ibañez  Carla Bottari  Domenica Termini 《Pure and Applied Geophysics》2005,162(4):747-760

A modelling of the observed macroseismic intensity of historical and instrumental earthquakes in southern Spain is proposed, with the aim of determining the macroseismic parameters for seismic hazard evaluation in a region in which the characterization of intensity distribution of seismic events shows different levels of difficulty referable to the complex faults system of the area in study. The adopted procedure allows an analytical determination of epicenters and principal attenuation directions of earthquakes with a double level of verification with reference to the maximum shaking area and structural lineaments of the region, respectively. The analyses, carried out on a suitable number of events, highlight, therefore, some elements for a preliminary characterization of a seismic zonation on the basis of the consistency between seismic intensity distribution of earthquakes and corresponding structural framework.  相似文献   

虚拟现实和G IS系统集成方法分析   总被引：1，自引：0，他引：1  

付哲  周云轩  刘殿伟  董月娥 《吉林大学学报(地球科学版)》2005,(Z1)

从三个角度论述虚拟现实(V irtua l R ea lity,VR)和地理信息系统(G IS)集成的必要性,通过对集成方法的归纳,提出4种集成方式,并详细介绍了各自的结构体系和具体特征。在此基础上划分了VR与G IS系统集成的4个阶段,分析当前系统集成现状,指出其发展趋势。同时探讨了VR和G IS系统集成中存在的关键问题,包括数据、虚拟景观技术、VRG IS网络化等,给出目前解决这些问题的一些建议和具体途径。  相似文献   

固体潮观测数据预处理中的一些常用方法及其计算机实现     

熊先保 《福建地震》2005,(Z1)

试图从台站产出的原始地形变前兆数据出发,提出一些实际操作性较强的预处理方法,从已编制好的软件中给出处理实例,从而达到提高台站观测人员的科研能力,填补资料预处理方面的某些空白的目的,这对于台站人员集观测、科研于一体有着十分重要的意义。从95-01-02项目厦门地震台前兆数据预处理的实践表明:这些方法取得了明显的实效,直到今天仍然具有很大的使用价值。  相似文献   

Comparison of runoff characteristics of two adjacent basins in a tropical rainforest using a modified hydrologic cycle model with outflow          下载免费PDF全文

Taeko Wakahara  Katsushige Shiraki  Masakazu Suzuki 《水文研究》2014,28(3):509-520

We propose a new runoff model including an outflow process that was applied to two adjacent basins (CL, TL) located in Lambir Hills National Park in north‐central Sarawak, Malaysia. Rainfall, runoff, topography, and soil layer thickness were observed. About 19% of annual runoff was observed in the CL basin (21.97 ha), whereas about 46% was observed in the TL basin (23.25 ha). It was inferred that the CL basin has an outflow because of low base flow, small runoff peak, and excessive water loss. By incorporating the outflow process into the HYdrological CYcle MODEL, good agreement between the data generated by the model and that observed was shown, with the exception of the data from the rainless period. Then, the fitting parameters for each basin were exchanged, except for the outflow parameter, and the characteristics of each basin were compared by calculating virtual runoff. As a result, the low base flow of the CL basin was estimated by the movement of the rainwater that escaped from the basin as deep percolation or lateral flow (11% of rainfall). The potential of the CL basin for mitigating flood and drought appeared to be higher than that of the TL basin. This is consistent with the topographic characteristics of the CL basin, which has a gentler slope than the TL basin. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   

基于Skyline的房地产三维虚拟系统的研究     

隋德志  兰磊 《测绘与空间地理信息》2016,(6):85-87

针对房地产行业的特点,采用3ds Max建立三维模型,并利用Skyline组件进行系统开发,运用虚拟现实技术和三维GIS技术对房地产进行三维建模,以及三维空间分析。系统建立在房地产小区影像数据、地下管线数据库的基础之上,具备三维场景浏览显示、空间量测、空间分析等功能模块。实现对房地产的地面建筑物、附属物、地下管线数据的统一浏览、显示,提供一个包括房地产的地面建筑物、附属物、地下三维管线的具有沉浸感和用户交互的房地产三维虚拟系统,以及一些实用的三维分析功能,为房地产的管理、维护、宣传和规划提供辅助决策支持。  相似文献   

面向WebGL的矢量数据三维绘制技术     

欧阳峰  龚桂荣  何列松 《测绘科学技术学报》2016,(6)

矢量数据的叠加显示能够提高三维虚拟地球的表达效果与分析能力。受限于GPU的计算精度,在三维虚拟地球中矢量数据绘制普遍存在抖动现象和深度冲突现象。对基于WebGL的矢量数据三维绘制中计算精度问题进行了分析,提出了使用CPU RTC技术和GPU RTE技术提高顶点变换的精度,使用多视锥渲染算法和深度平面技术解决深度缓存精度问题。实验证明,这几种技术和算法可以有效缓解抖动现象和深度冲突现象导致的视觉干扰,改善了各种尺度和范围的矢量数据在三维地形上的叠加显示效果。  相似文献   

Integrating ASTER and GLASS broadband emissivity products using a multi-resolution Kalman filter     

Linpeng Shi  Shunlin Liang  Quan Zhang 《International Journal of Digital Earth》2016,9(11):1098-1116

In this study, the multi-resolution Kalman filter (MKF) algorithm, which can handle multi-resolution problems with high computational efficiency, was used to blend two emissivity products: the Global LAnd Surface Satellite (GLASS) (BBE) product and the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) narrowband emissivity (NBE) product. The ASTER NBE product was first converted into a BBE product. A new detrending method was used to transfer the BBEs into a process suitable for the MKF. The new detrending method was superior to the two existing methods. Finally, both the de-trended GLASS and ASTER BBE products were incorporated into the MKF framework to obtain the optimal estimation at each scale. Field measurements collected in North America were used to validate the integrated BBEs. Visually, the fusion map showed good continuity, with the exception of the border areas, and the quality of the fusion map was better than that of the original maps. The validation results indicate that the MKF improved the BBE product accuracy at the coarse scale. In addition, the MKF was capable of recovering missing pixels at a finer scale.  相似文献