差分算子

最佳差分算子在P-SV波正演模拟中的应用

Optimum difference operator applied to p - SV wave forward simulation

通过定义平移算子和差分算子，并利用Lax配对的方法，找到了KP差分-微分方程组的正确形式。

Through defining translation operator and difference operator and using method of Lax pair , the correct form of the system of KP difference / ? differential equations has been found out .

基于中心-差分算子的不对称FIR滤波器

Asymmetric FIR filters based on central - difference operators

介绍了基于中心-差分算子的不对称有限冲击响应（FIR）低通滤波器。

A asymmetric FIR low - pass filters based on central - difference operators is described .

首先从VTI介质中准P波方程出发，采用任意偶数阶精度有限差分算子构造了准P波方程数值求解的高阶有限差分格式，给出了其稳定性条件和边界条件的计算方法。

Based on the quasi-P wave equations in VTI media , a high-order finite-difference scheme was derived by using an even-order accurate difference operator , the stability conditions and the absorbing boundary conditions were also provided .

本文结合Lyapunov矩阵方程和差分算子稳定性的结果，采用一些解析方法，给出了一类中立型线性控制系统一致渐近稳定的充分条件。

Applying the result of the stability of differential operator and Lyapunov matrix equation , and using several analytic methods , this paper gives the sufficient conditions of the uniformly asymptotically stability for a class of linear neutral system .

本文在该方程中进一步引入了Crank-Nicolson一阶有限差分算子来代替中心差分算子，从而得出了45°无条件稳定差分格式的单行波方程。

Replacing the central difference operator with finite first order difference operator ( Crank-Nicolson ), we can get 45 ° one-way wave equation in unconditionally stable difference scheme .

用最佳差分算子模拟P-SV波的计算速度比用传统差分格式至少快一个数量级，比目前公认的速度较快的伪谱法还要快3&5倍。

Velocity computation using optimum difference operator to simulate P-SV waves is at least one order of magnitude faster than using conventional finite difference schemes and 3 to 5 times as fast as the pseudospectral method which is currently accepted to be the fastest one .

本论文用连分式近似单程波波动方程中的平方根导出FFD算法的基本公式，并对FFD算法中的有限差分算子进行了系数优化，进一步提高了计算的有效性。

In the thesis , the fundamental formula of FFD method derives from the square root that is approximated by a continued fraction expansion in the one-way wave equation . Optimizations of the parameters of the finite-difference operator improve the validity of the method .

该方法建立在空间微分的最佳差分算子（Holberg，1987）的基础上，采用类似于Virieux（1986）所用的那种交错网络技术，在不同网格点上计算不同的波场量。

The method , based on the optimized difference operator for spacial differential ( Holberg , 1987 ), adopts the staggered grid scheme similar to that of Virieux ( 1986 ), and calculates the wave field which differs at different grid points .

算子与微分方程关于解常微分方程的差分算子法的最优算法

On the optimum algorithm of difference operator methods for solving ordinary differential equations

形态差分算子与图象形态滤波

Morphological Difference Operation and Morphological Filtering of Image

解常微分方程的差分算子法

Difference operator methods for solving ordinary differential equations

一种用差分算子变换求过渡矩阵的新方法

A New Method of Finding Amplification Factor by Fourier Transform of a Difference Operator

差分算子在概率论中的应用

Application of Differential Operators in Probability Theory

不同于传统差分算子用泰勒展开近似求得，最佳差分则是通过使群速度相对误差最小求得。

The optimal-operator is designed by minimizing the corresponding peak relative error in group velocity .

线性扰动系统解的渐近性质及四阶奇异差分算子的谱问题

Asymptotic Behavior of Solutions of Linear Perturbed Systems and Spectral Problem of Singular Fourth-Order Difference Operators

为了实现血细胞图像的自动识别，提出了一种基于差分算子和区域增长的方法。

This paper proposes a new approach based on difference operator and region-growing to automatically recognize cell image .

显然，差分算子及其逆算子是阶乘幂多项式的方便工具。

Clearly , the difference operator or sum operator is the convenient tool for the polynomial of factorial powers .

然而，解析性微分算子和离散性差分算子的差异却是造成数值计算的原始误差源。

The difference between the differential and the finite-difference operator is however a primitive error source in the numerics .

避免了不准确的二阶中心差分算子，对自由表面、人工边界及交接层面可以方便且精确处理。

According to this method , the free surface , artificial boundary and interface can be processed easily and accurately .

同时，还研究了在受脉冲噪声污染的情况下，如何用形态差分算子准确地提取图象的边缘，并提出了几种具有抗噪能力的数学形态边缘检测算子。

In the mean time , several anti-noises morphological differentiating operators are developed to deal with the images corrupted by impulses .

扩散中心的步进移动依赖于图像的结构信息，通过八邻域差分算子来确定步进移动的方向。

The first mechanism depends on the information of the image structure , to determine the direction of stepping move through the eight neighborhood difference operator .

在正演模拟中，为了克服常规差分算子的数值频散，采用了25点优化差分算子；

During the process of forward simulation , in order to overcome the numeric dispersion in ordinary finite-difference operator , we adopted optimized 25 points finite-difference operator ;

利用一阶偏导数项的四阶紧致差分算子，直接推导出了数值求解二维对流反应方程的一种新的高精度紧致差分格式。

Making use of the fourth-order compact difference formula of the first derivative term , anew high accuracy difference scheme for the two-dimensional convection reaction equation is proposed .

这里，提出了自定义差分算子来提取道路图像边缘，利用每个像素的八个相邻点，用不同的权值进行求和运算。

A self-defined difference operator is then proposed to extract the image edge , by the sum of a pixel and its eight adjacent pixels with different weights .

与微分算子及其逆算子积分算子作比较，讨论了差分算子及其逆算子（和分）。

In comparison with the differential operator and its inverse - integral operator , the difference operator and its inverse ( sum operator ) are discussed in this paper .

利用傅里叶有限差分算子可保证在复杂构造的波场延拓中，地震波场不失真，成像质量高。

Fourier finite difference operator can be adopted to ensure good fidelity of seismic wave field in wave field continuation of complicated geology structure , bringing high quality image .

采用斜向差分算子，建立斜向隐式差分格式，再结合边界条件，对扩散方程进行求解。

Based on the skew direction difference operator , the implicit skew difference schemes were constructed , and the boundary condition was unified , to solve the diffusion equation .

试验结果表明：引入空间滤波器的拉普拉斯算子可在保证高实时性的前提下获取低噪声的且更加完整的边缘检测结果。拉普拉斯差分算子同步降噪空间滤波器设计

The result indicates that the dimensional structure filter edge method can obtain a more intact and less noise image segmentation . Design of synchronization dimensional structure filter for Laplace operator