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在介绍球面小波理论的基础上,推导和比较了几种球面小波,分析了最新地球重力模型-EGM96,以此为依据,把球面小波多分辨分析用于计算全球自由空气异常及重力大地水准面,并对处理结果做出解释。 相似文献
135.
HUANG Guangyuan 《中国科学D辑(英文版)》2001,44(2):159-165
Some new imaging formulas for seismic reflection wave and their theoretical basis are given. Phenomena of wave propagation
should be characterized by instantaneous spectrum and expressed by complex function of three variables (time, space and frequency)
in mathematics. Various physical parameters of medium are also complex functions of two variables (space and frequency). The
relationship between reflection coefficient of medium and spectrum of reflected wave is given. Multi-reflection and filter
of formations are considered in inversion formulas. Problems in classical convolution model and wave equation are illustrated.
All these inversion formulas can be used to image underground medium by wavelet transform and method of “3-basic colors”.
Different colors mean different media. 相似文献
136.
A wavelet‐based random vibration theory has been developed for the non‐stationary seismic response of liquid storage tanks including soil interaction. The ground motion process has been characterized via estimates of statistical functionals of wavelet coefficients obtained from a single time history of ground accelerations. The tank–liquid–soil system has been modelled as a two‐degree‐of‐freedom (2‐DOF) system. The wavelet domain equations have been formulated and the wavelet coefficients of the required response state are obtained by solving two linear simultaneous algebraic equations. The explicit expression for the instantaneous power spectral density function (PSDF) in terms of the functionals of the input wavelet coefficients has been obtained. The moments of this PSDF are used to estimate the expected pseudo‐spectral acceleration (PSA) response of the tank. Parametric variations are carried out to study the effects of tank height, foundation natural frequency, shear wave velocity of soil and ratio of the mass of tank (including liquid) to the mass of foundation on the PSA responses of tanks. Copyright © 2001 John Wiley & Sons, Ltd. 相似文献
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LlPingxiang WANGZhijun 《地球空间信息科学学报》2003,6(2):31-34
On the basis of a thorough understanding of the physical characteristics of remote sensing image,this paper employs the theories of wavelet transform and signal sampling to develop a new image fusion algorithm.The algorithm has been successfully applied to the image fusion of SPOT PAN and TM of Guangdong province, China The experimental results show that a perfect image fusion can be built up by using the image analytical solution and reconstruction in the image frequency domain based on the physical characteristics of the image formation.The method has demonstrated that the results of the image fusion do not change spectral characteristics of the original image. 相似文献
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遥感影像镶嵌时拼接缝的消除方法 总被引:29,自引:0,他引:29
对现有的影像并接缝消除方法的优缺点进行了分析,提出了拼接缝消除的强制改正方法,并用大量的实际图像进行了试验。结果表明:所提出的方法具有较好的拼接缝消除效果,且算法简单,易于实现,可以处理彩色和黑白等多种图像。 相似文献