rytov approximation meaning in Chinese
利托夫近似
Examples
- Traditional method can be classified two class : linear optimization technique and nonlinear optimization technique , linear optimization technique base on born approximation or rytov approximation is usually used to solve weak scattering problem
线性优化方法采用线性近似忽略了散射体内部的多次散射，可以有效的反演低对比度的问题，但对于高对比度问题的求解则有可能不收敛。 - Author , starts from the one - way wave equation of wavefield extrapolation , research the relationship and transform condition of wavefield extrapolation operators , and propose the steady variational reference slowness rytov approximation general screen wavefield extrapolation operator ( vrselrf ) which can adapt severe lateral velocity variations , in frequency - wavenumber domain , and the improved wavefield extrapolation scheme , also give the method to improve the computation efficiency . the achievement establishes the theoretic basis of the whole research
首先，从波场延拓的单程波方程出发，系统地研究了频率波数域的波场延拓算子之间的相互关系和转换条件并在此基础上提出了能适应剧烈横向变速的频率波数域稳定的变参考慢度rytov近似广义屏波场延拓算子( vrselrf )和部分波场延拓改进方案及提高运算效率的措施，为整个研究打下理论基础。 - Author , secondly , starts from the approximate expandness of square root operator , perform mathematical calculations for finite difference operator in frequency - space domain , fourier finite difference operator in mixing domain ( frequency - space and frequency - wavenumber domain ) and general screen operator in mixing domain , compare and discuss their precision of their wavefield , adaptability for lateral velocity variations , computation efficiency and stability . thirdly , author , applies the steady variational reference slowness rytov approximation general screen wavefield extrapolation operator ( vrselrf ) in frequency - wavenumber domain , to the prestack and poststack forward modeling and depth migration
第二，从平方根算子的近似展开出发对频率?空间域的有限差分算子、混合域(频率?空间域；频率?波数域)的fourier有限差分算子、混合域的广义屏算子进行了推导并对其波场描述精度、对横向变速的适应性、计算效率和稳定性进行了比较与评述。