波场外推的英文

• wave field extrapolation

• "波"英文翻译    wave
• "场"英文翻译    a level open space; threshin ...
• "外"英文翻译    outside; external side
• "推"英文翻译    push; shove
• "二维波场外推" 英文翻译 :    two-dimension wave extrapolation
• "波场" 英文翻译 :    range; wave field
• "场外" 英文翻译 :    off court; offcourtt; out of bounds
• "外推" 英文翻译 :    augmentation; extrapolate; extrapolation
• "光波场" 英文翻译 :    light wave fields
• "基波场" 英文翻译 :    field of first harmonic
• "微波场" 英文翻译 :    microwave field
• "谐波场" 英文翻译 :    harmonic fields
• "行波场" 英文翻译 :    traveling-wave field; traveling-wavefield; travelling field; travelling-field
• "驻波场" 英文翻译 :    standing wave field; standing-wave field; stationary field
• "外推，外推法" 英文翻译 :    extrapolation
• "场外；厂外" 英文翻译 :    off-site
• "场外的" 英文翻译 :    off field; off-board; off-market; over the counter
• "球场外" 英文翻译 :    off the court
• "推断，外推" 英文翻译 :    extrapolate
• "外推窗" 英文翻译 :    out ward opening window; out-swinging window
• "外推的" 英文翻译 :    extrapolated
• "外推法" 英文翻译 :    extrapolated method; extrapolation method; extrapolation technique; method of extrapolation; trend projection
• "外推力" 英文翻译 :    outward thrust
• "外推面" 英文翻译 :    extrapolated side
• "外推器" 英文翻译 :    extrapolator

• From the mathematical point of view , the difficulty stems from the inability to get , with the traditional global transform like the fourier transform , a simplified differential equation that governs the evolution of the basic function through the non - homogeneous medium
  这些基本函数的全局特性使其在非均匀空间的演化变得十分复杂，从而影响了传统方法的波场外推精度及效率。
• 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。
• The recognition of the global nature of propagators as the difficulties " physical genesis led researchers to develop and investigate propagation methods based on the expansion of the total field by sets of spatially confined wave functions , or in other words , to construct localized wave field propagators instead of the traditional global propagators
  认识到全局性传播算子在波场外推中的困难，近二十年来，许多研究都致力于发展基于波场局部空间分解的局域化传播算子以替代传统的全局算子。
• 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。
• Essential to their utility is the requirement that the evolution of the basic functions through the propagation environment constitutes a simplified problem with an exact or approximate closed form solution to the original wave equation . the evolution of a spatial fourier harmonic through a homogeneous medium is governed by a reduced wave equation , obtained by applying the fourier transform to the helmholtz equation , with a simple and well - known solution - the plane wave
  这些方法均采用一组具有全局特性的基本函数对波场进行分解，如占据整个空间的富氏调谐函数或充满各个方向的dirac函数(点源) ，并通过求解基本函数满足波动方程的精确解或近似解来达到波场外推的目的。