| 1. | Study on seismic wavelet extrapolation method
地震子波外推方法研究 |
| 2. | An extrapolation method for collocation solution of class of integral equation
一类积分方程配置解的外推 |
| 3. | In explicit depth extrapolation method of frequency - space fields , wavefield depth extrapolation is completed with convolution of short explicit difference operators and the wavefield
摘要在频率空间域显式叠前深度偏移中，波场深度延拓是通过显式差分短算子与波场的空间褶积完成的。 |
| 4. | Extrapolation method , composed of aitken extrapolation and eigenvalues - based algorithm mainly , can notably reduce iterations commonly . aitken extrapolation algorithm use aitken transform to reduce iterations
Aitkenextrapolation算法使用aitken变换以减少迭代次数，但aitken变换在多数情况下无法确保算法收敛。 |
| 5. | The results show that all the orders of the stress singularities at the interface edge can be determined precisely , and the related stress intenisity coefficients can also be determined by extrapolation method
计算结果表明，本方法可以精确地求得振荡应力奇异性次数，并且与奇异性对应的复应力强度系数也可以很方便地应用外插法得到。 |
| 6. | 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。 |
| 7. | 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。 |
| 8. | Second , for vector sequence coming from the steep - descent method , we use extrapolation method for the sequence and get some applied algorithms . we also give theoretical proofs for this algorithms . many numerical experiments tell us that the new algorithms sometimes can save 80 % computation
其次，对求解非线性优化问题的最简洁的最速下降方法产生的迭代序列，运用向量序列加速收敛手段进行了讨论，导出了一些实用的加速算法，并从理论上证明快速算法的有效性，众多数值试验进一步表明：加速收敛的方法相比较加速前几乎都能够节约80以上的计算量。 |
