wave field extrapolation meaning in English
波场外推
波场延拓
Examples
- Advanced mathematical technologies , especially the newly developed wavelet transform and the frame theory , provide a solid foundation for such an effort . the ray - theory based beam - summation method , such as the complex source - generated beam and the gaussian beam methods , and the local phase - space domain ( beamlet domain ) wave field extrapolation methods employing windowed fourier transform ( wft ) or wavelet transform are proposed consequently
基于射线理论的高频渐近射束(复射束、高斯射束)叠加方法，以窗口富里叶变换( wft )以及小波变换为基础的局部相位-空间域(小波束域)波场外推方法等相继产生。 - One is the non - orthogonal gabor - daubechies frame , or g - d frame , a complete set of discrete window fourier functions which are constructed by space - shifting and harmonically modulating a gaussian window . although a g - d frame is not an orthogonal basis , it bears considerable advantages for the study of physical problems , especially those related to the wave field extrapolation , due to the optimal localization properties of the gaussian window function under the heisenberg uncertainty principle
其一为将高斯窗函数经平移和调制而构成的一组窗口富里叶框架( gabor - daubechies框架，或g - d框架)基本函数，另一种为在富里叶分析和小波包理论基础上发展起来的局部余弦基函数。 - This conversion is based on the analytic expression of sonic and elastic wave equation , and use the different wave field extrapolation , which is initially used in seismic migration and forward modeling . this paper introduces the easy and efficient finite - difference method to realize the conversion by comparing three different methods
论文经过对三种常规波场延拓方法( kirchhoff积分法、频率波数域法和有限差分法)优缺点的比较，采用了简单易用的有限差分方法来实现这种转换。 - In this thesis , we follow the idea of the beamlet - domain wave field extrapolation methods to construct localized propagators . through comparative study of signal decomposition efficiency using different representation schemes , we select two groups of basic functions with simple expressions and good localization properties for wave field decomposition , propagation and imaging
本论文通过对wft 、小波基、小波包，以及相关的框架理论等的分析比较，选择了两组形式简单，且具有适宜于波场外推特性的基本函数集合来进行波场分解、传播及偏移成像问题的研究。 - The other is the local cosine bases developed as a kind of orthogonal basis based on the fourier analysis and wavelet - packet theory . in this thesis , theoretical analysis and numerical applications are mainly focused on the beamlet - domain wave field extrapolation using g - d frame propagators . the whole thesis consists of six chapters
通过对具体信号的分析，对不同变换方法的信号表示效率进行了对比，并总结了g - d框架及对其进行尺度扩展组成的gabor函数族在应用于波场相关的研究中时，优于其它正交分解方法的特性。