查询词典 ill conditioned matrix

On the basis of the conversion relation of inverse matrix and adjoint matrix, by using 1/ω instead of |B'(xBx(subscript k|, a new Landweber iteration formula x(superscript δ subscript k+1)=x(superscript δ subscript k)-ωB'(x(superscript δ subscript k)Bx(superscript δ subscript kB'x(superscript δ kf(x(superscript δ subscript k)-y(superscript δ)is constructed for solving rank deficiency nonlinear least squares problem, with which the phenomenon that leads to ill-posed problem because the iteration matrix is rank-deficient and very ill-conditioned in numerical iterative process is avoided.

基于逆矩阵和矩阵伴随算子的换算关系，并用1/ω代替|B′(xBx(下标k|，构造出一个新的求解秩亏非线性最小二乘问题的Landweber迭代格式，x(上标δ下标 k+1)=x-ωB'(xBx(上标δ下标 k*B'x(上标δ下标 kf(x-y，从而避免了在迭代过程中由于迭代矩阵的秩亏和病态而产生的不适定现象。

Because the rank of the augmented channel matrix is always equal to the number of transmitting antennas, the algorithm can work well in an ill-conditioned channel.

由于扩展信道矩阵的秩等于发射天线数，该算法对信道缺秩的情况不敏感。

When to get the coefficients of polynomial directly,the ill-conditioned matrix may be produced and effect the precision of result.Using orthogonal polynomial can avoid this problem.This paper introduces 4 orthogonal polynomial.In our discussion,it is proposed to use Chebyshev polynomial and Legendre polynomial,they are easier to sa...

讨论4种常用正交多项式在拟合卫星轨道与时间函数时的适用性；通过计算实例说明利用切比雪夫多项式和勒让德多项式做数据拟合时具有很高的精度；分析得出评定多项式拟合数据精度的适用阶数，实际应用中可降低工作量，提高计算效率；最后讨论同一多项式阶数下不同历元数对拟合结果的影响。

If the Landweber method and pre-iteration method were convergent, the residue sequence would be monotone decreasing. By analyzing the convergence, the fact is demonstrated that for the severe ill-conditioned matrix of sensitivity coefficient, because of the limitation of the precision of the computer, the residue sequence is not monotone decreasing; thereby the reconstruction images diverge from the true distribution of the conductivity. So the generalized inverse method with threshold is established and the selection way of the regularization parameter is presented, by which the better images are reconstructed.

Landweber法和预迭代法收敛，则其残差序列单调递减，通过对它们的收敛性进行分析，证实对于病态性严重的灵敏度系数矩阵，由于受计算精度的限制，迭代过程中的残差序列不再单调递减，从而导致重建图象偏离实际电导率分布，因此作者建立了带阈值的广义逆算法，提出了规则化参数选择方法，获得了较好的图象重建质量。

The resulting linear system, the coefficient matrix of which is, typically, a 2 x 2 block symmetric or non-symmetric and singular or non-singular indefinite matrix, is of high order and ill conditioned. In order to solve such system we have to use iterative methods with fast convergence speed.

所得的离散方程组（其系数矩阵典型地是 2 x 2 块对称或非对称，奇异或非奇异的不定矩阵）是高阶和病态的，为了求解这样的方程组我们必需使用快速收敛的迭代方法。

The PSD-PCG algorithm is effective to sovle ill-conditioned linear system of equations whose coefficient matrix is symmetric and positive definite and sparse.

本章提出的PSD—PCG法是解对称正定的稀疏病态线性方程组的有效算法。

In order to achieve accurate solutions of ill-conditioned GPS equations with a few observational epochs, the ill-conditioned normal equations of GPS rapid positioning was transformed as a function optimization problem. Then genetic algorithm was used to calculate parameter solutions, which avoided the inversion of coefficient matrix of normal equations.

为准确解算仅有少数几个历元的GPS载波相位观测数据的病态定位方程，将GPS快速定位的病态法方程求解问题转化为一个函数优化问题，应用遗传算法求解病态方程，避免了法方程的求逆运算，从而可以得到参数的近似最优解。

In this thesis, various conventional and ill-conditioned load flow calculation methods have been fully analyzed and evaluated in the aspect of convergence, and the relationship between the convergence and the Jacobian matrix of polar type load flow equation has been discussed and evaluated.

本文对常规潮流算法和常用病态潮流计算方法进行了全面的算法、收敛性分析、评价、比较。

In chapter 5, we investigate the iterative methods for solving the linear systems by the homotopy perturbation technique, and the numerical rank of a matrix in the matrix computations are considered, especially the ill-conditioned matrices.

本文第五章中我们首先利用同伦摄动技巧考察了线性方程组的迭代解法。其次，从数值计算的角度考察了矩阵的数值秩问题，尤其是病态矩阵。

While the LCLS method is used to minimize the energy of the linearly fused information, the neural-network algorithm is developed to overcome the ill-conditioned and singular problems of the sample covariance matrix in the LCLS method.

LCLS方法用来最小化线性融合信息的能量，而神经网络算法则用来处理出现于LCLS方法中的样本协方差矩阵的不良条件和奇异性问题。

The absorption and distribution of chromium were studied in ryeusing nutrient culture technique and pot experiment.

采用不同浓度K2CrO4(0，0.4，0.8和1.2 mmol/L)的Hoagland营养液处理黑麦幼苗，测定铬在黑麦体内的亚细胞分布、铬化学形态及不同部位的积累。

By analyzing theory foundation of mathematical morphology in the digital image processing, researching morphology arithmetic of the binary Image, discussing two basic forms for the least structure element: dilation and erosion.

通过分析数学形态学在图像中的理论基础，研究二值图像的形态分析算法，探讨最小结构元素的两种基本形态：膨胀和腐蚀；分析了数学形态学复杂算法的基本原理，把数学形态学的部分并行处理理念引入到家实际应用中。