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321.
频谱分析法在核爆与地震识别中具有广泛的应用.但是频谱分析方法是稳态方法,即使采用Gabor变换,也因时-频窗口形状不变而分辨串较低.为提高时-频分辨率,本文将小波变换理论用于乌鲁木齐台记录的地震与核爆事件的分析,并提出了识别核爆和天然地震的小波包分量比判据.通过对加拿大黄刀地震台记录的印度地下核爆的分析,进一步验证了小波包分量比判据对核爆和地震的识别具有较高的识别效率.结果表明:对于地震信号,其小波包分量比U03/U1一般都大于1.0,而对于核爆信号,比值U03/U13一般都小于1.0. 相似文献
322.
László Szarka 《中国地质大学学报(英文版)》2009,20(3)
As I learned it from extensive geo-electromaguetic analogue modeling experiments, some specific nonconventional interpretation parameters, in certain conditions, give more detailed information about the geometry of subsurface resistivity inbomogeneities than the routinely used parameters. In this article, I show several examples, and I present how these early results influenced our later research. An enhanced geometric sensitivity may be due to special array geometry (as we call It "null array"), or it may be due to a narrow and very special frequency range (Le., the so-called "keyhole" range). Nonconventional but physically based interpretation parameters (like the Poyuting vector) or higher order invariants of resistivity or impedance tensors may also give useful additional information about the shape of subsurface bodies. One should be very careful in their application because a large part of these nontroditioual approaches are strongly constrained by measuring errors and geological noise. 相似文献
323.
基于通用一体化符号编辑器的符号共享模式研究 总被引:6,自引:1,他引:5
该文总结现有符号共享模式的原理与特点,提出基于通用一体化符号编辑器的符号共享模式,即通过构建通用一体化符号编辑器,将GIS平台的符号渲染绘制流程组件化以实现符号的共享。介绍符号的数据组织、存储索引机制以及通用一体化符号编辑器的特点,分析SuperMapⅢ的符号渲染绘制组件和符号库操作引擎,实现通用符号库在不同GIS环境的-致显示和符号资源的共享。 相似文献
324.
The quantitative evaluation of key factors of soil variability together with the spatial pattern of underlying variables are important steps in understanding the functioning of soilscapes. Fifteen physical and chemical variables describing 24 pedons were used to elucidate processes of soil differentiation in a humid forest environment in Southern Cameroon. Landscape positions delineated on the basis of remote-sensed imageries included flat convex summits (FCS), linear valley slopes (LVS), colluvial inland valleys (CIV), and alluvial floodplain. Ordination by principal component analysis (PCA) resulted in a three-factor model, which efficiently summarized the dataset explaining 81.4% of total soil variance (TSV). The pedogenetic factor of ferralitization emerged as the main factor accounting for 43.7% of TSV. Identified underlying processes included basic cation leaching, solum acidification, and in situ clay build up. Cation exchange properties as influenced by organic constituents and soil available P were the second and third most important factors associated with 26.7 and 11.4% of TSV respectively. Organic constituents and related biological processes had strong control on nutrient availability and cation-exchange properties, while soil available phosphorus (AP) showed a strong dependence on potential acidity and organic matter mineralization status. The analysis of variance highlighted significant differences for most soil properties across landscape position and soil depth except for organic carbon (OC), total nitrogen (TN), and total phosphorus. All the soils, however, have low pH, low basic cation saturation, and correlatively high exchangeable Al irrespective of their position in the landscape. 相似文献
325.
立足于组件式GIS技术,结合哈尔滨市基础空间地理信息系统的建设与实施,阐述了利用组件式GIS平台进行GIS建设的方式、方法以及采用该方法的优势、现状和未来的发展趋势等内容。 相似文献
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????IGS???????GIM???????????????TEC??Total Electron Content?????????2007-2011???????й??????????17???M??≥6.0????????????????????PCA??Principal Component Analysis?? ???????????TEC??????????????????????????б???????????PCA??????????????????????????????????????????£???????????????TEC????????????????????????????0~5?? 相似文献
329.
����ȱʧ��GNSSʱ�����з�����Ӱ�� 总被引:1,自引:0,他引:1
??GNSS?????????????????????????????????????????????????????GNSS??????з??????????????????????????????????????????????????????????????????????????????????????????????????????????????????????£??????????????????????????????????????岹??????????????????????????????????????????????????????????????????????????????????????????????????????????仯??????£?????????????????й????????????????????10%??????統???????9 mm???????????????????11???????????????12?????????GNSS????????????????о???????????????GNSS?????????????????????????? 相似文献
330.
Three main topics including the floor motion action mechanism, the test frame design, and the target spectrum simulation presented in the paper are discussed specifically. Floor motion action mechanism is critical in understanding the seismic performance of architectural nonstructural components. Seismic sensitiveness and earthquake response properties of the nonstructural components should be considered in the design of the test frame for the shaking table test. Target spectrum simulation is also a challenging job in the shaking table test, in which dynamic characteristics of the specimen, performance of the shaking table facilities, and the control techniques should be all considered. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献