查询词典 least squares

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。

The order and time delay of the dynamic model are assumed to be unknown a priori. A time-weighted digital filter is employed to group of linear algebraic equations. The moving horizon least-squares algorithm is then developed to estimate the model parameters in a recursive fashion.

该法应用一时间加权离散滤波器将特定时段内取样的输出入讯号转换成一实数，然后利用不同时段的量测讯号以移动区间递回最小平方演算法来估测模型参数。

The PSF values can be estimated by alternating iterative minimizing the objective function, and the object images can be restored by the constrained least-squares filtering method.

将小波变换与分解的多分辨特性和时频局部化特性应用在湍流退化图像的盲目复原中，降低了算法的计算复杂性并提高了其抗噪能力。

The algorithm consists of a least-squares part providing an analytica l initial solution,and a projection part that projects the initial least-square s solution successively onto each equality constraint.

该算法有两个显著特点：一是目标函数的Hessian矩阵不要求正定；二是由于采用平方根因子分解来计算增广Hessian矩阵及投影算子矩阵，算法具有很好的数字稳定性。

Elliptical fitting matlab code, at least for the given five-point least-squares fitting of data.

详细说明：拟合椭圆的matlab代码，对给出的至少5个点的数据进行最小二乘拟合。

In the ***, all types and fundamental principles of Radon transform are summarized systematacially. This *** starts from the general linear Radon transform, and then researches how to use the damped least square method to find the solution of the forward transform. However, the least squares smoothing effect will lead to a certain degree of trails in the data of Radon domain, which led to the application\'s limitations. After that the implementation in Radon domain and relative merits of linear Radon transform, parabolic Radon transform and polynomial Radon transform which have time invariance are introduced, the conjugate gradient method that can solve numerical solution is also given. And then the high resolution Randon transform is discussed, it introduces the regularization theory and Bayes principle into inversion, which successfully remove the negative affect caused by discrete Radon transform. Finally, we introduce the optimal weighting similar coefficient Radon transform, which adapt to the time variant quality of hyperbolic Radon transform.

本文系统总结了Radon变换的各种类型及其基本原理，从τ- p变换(即一般线性Radon变换)出发，研究利用阻尼最小二乘平方法求解其正变换，但是最小平方法的平滑作用会导致Radon域数据存在一定程度的拖尾效应，给这种方法的应用带来了很大的局限性；然后先容了具有时不变性的线性、抛物和多项式Radon变换在频率域的实现及其优缺点，给出了求解其数值解的共轭梯度算法；接着讨论了高分辨率Radon变换，它把正则化思想和贝叶斯原理引进到了反演中，很好的克服了离散Radon变换产生的截断效应对结果的不利影响；最后先容了适应双曲Radon变换时变性质的高分辨率最优相似系数加权Radon变换。

Differential Evolution Orthogonal Least Square algorithm for RBF network is presented,a hybrid algorithm blending Orthogonal Least Squares method with Differential Evolution algorithm.

研究用于径向基函数网络训练的一种微分进化正交最小二乘算法。

Fist, comprehensive analysis on the current study on data processing is made, and characters of Newton methods about nonlinear surveying and mapping data processing are discussed, and then new solutions to parameters estimate with multi-sources, multi-types, multi-dimension, multi-precision bynonlinear least square are presented such as PSB algorithm, digital continuation and generalized digital continuation algorithm, cone model method, tensor analysis method, GCMA(mixed algorithm of gradient method and conjugate gradient method), combining algorithm based on Newton method and gradient method and confidence region and so on, and a new fast difference iterative algorithm is proposed towards parameters estimation containing random parameters in nonlinear models, and a new solutions to nonlinear least squares surveying and mapping adjustment by parameters estimation both considering the random and nonrandom parameters is presented after studying on nonlinear data processing in deformation monitoring, and at last primary analysis on error propagation of spatial data is made and approximate error propagation formula and error analysis formula to length and area are proposed.

首先比较全面分析了目前测量数据处理理论的研究现状，讨论了牛顿类方法在处理非线性模型参数估计方面的特点，研究并给出了求解多源、多类型、多维、多精度、非线性最小二乘测量平差参数估计的若干种新方法，这包括PSB算法、数值延拓及其广义数值延拓算法、锥模型法、张量分析法、基于最速下降法和牛顿法的组合算法、基于最速下降

In the second chapter, we present the traditional way of surface fitting ------LeastSquares. We present a kind of amendatory algorithm------Moving Least Squaresbased on Least Squares.

第二章介绍曲面拟合的传统方法——最小二乘法的理论，在此基础上，采用了一种改进的曲面拟合方法——移动最小二乘法。

Considering pencil of matrices with centrosymmetric could not satisfy characteristic equations in practice, it was necessary to study the centrosymmetric solution of the matrix equation least square problems, and to give pencil of matrices with centrosymmetric of the least squares problems in model updating.

对线性结构的有限元动力模型修正问题，通过灵敏度分析，确定要修正的参数，由正交性条件和特征方程得到相应的修正量方程。

According to the clear water experiment, aeration performance of the new equipment is good with high total oxygen transfer coefficient and oxygen utilization ratio.

曝气设备的动力效率在叶轮转速为120rpm～150rpm时取得最大值，此时氧利用率和充氧能力也具有较高值。

The environmental stability of that world - including its crushing pressures and icy darkness - means that some of its most famous inhabitants have survived for eons as evolutionary throwbacks, their bodies undergoing little change.

稳定的海底环境─包括能把人压扁的压力和冰冷的黑暗─意谓海底某些最知名的栖居生物已以演化返祖的样态活了万世，形体几无变化。