查询词典 least squares approximation

This approach was to replace the derivative operator in the continuous time model by an approximation and estimation of the physical parameters of structures by the least-squares method.

讨论了导数近似值的选择方法，并分析了算法的收敛性。

Keywords Closed convex cone;gradient projection method;Least-squares solution;Inverse matrix problem;Inverse eigenvalue problem;Matrix completion problem;Optimal approximation

Article From 湖南大学；应用数学博士论文 2005年度闭凸锥；投影梯度法；最小二乘解；矩阵反问题；矩阵逆特征值问题；矩阵完全化；最佳逼近

It provides a way to find optimal lower dimensional approximations of the given data, and It enormously reduce the storage of the data which is needed when the physical processes is recurred. The physical process can be described in series expansion function that only is related to the time and space. It is optimal approximation of the given data in a certain least squares optimal sense. The most obvious advantage of the method is that it reduces the computation cost and computation time markedly.

它提供了一种描绘物理过程的有效方法，该物理过程可以写成一个只与时间相关的函数和一个只与空间相关的函数的展开式序列，且它们在均方意义上是最优的，在展开式中只需要少量的项数就可较准确地描述该物理过程，因此降低计算维数、减少计算量和节省计算时间是这个方法最明显的优点。

Commonly used algorithm c language, including some classic example, least squares, interpolation and approximation, etc.!

详细说明：常用算法的c语言实现，包括一些经典的比如，最小二乘，插值与逼近等等！

Secondly three kinds of approaches of function approximation are discussed which are the interpolation with radial basis function, moving least squares and approximate approximation. And the correlative theories are proved.

在此之后介绍了求解偏微分方程数值解的两种无网格方法：无网格伽辽金方法和无网格局部Petrov-Galerkin方法。

Identification ; parameter estimation ; least squares method ; approximation ; adaptive lilter/kalman filtering

辨识；参数估计；最小二乘法；逼近；自适应滤波器/卡尔曼滤渡

This dissertation focuses on the spherical wavelet expansion of the earth gravity field and its application. Based on the concept of the integration approaches and radial basis functions the spherical wavelet is put forward, with that the earth gravity field is described in a new way, and some other researches are conducted, they are: spherical wavelet regularization, multiscale approximation of satellite gravity measurement, down continuation of airborne geavimetry data, the least squares properties of geopotential wavelet approximation, the spherical wavelet solution of two kinds of BVP and spherical selective multiscale reconstruction.

本文围绕地球重力场的球面小波展开及其应用进行研究，在积分逼近与径向基函数概念的基础上引入了球面小波，利用球面小波对重力场展开进行了重新表示，在此基础上进行了球面小波正则化、卫星重力多尺度逼近、航空重力数据向下延拓、重力场球面小波逼近的最小范数性质、两类边值问题的球面小波实用解、球面选择多尺度去噪方法等方面的研究。

Keywords constrained matrix equation problem;sub matrix constraint problem; matrix norm; optimal approximation solution;least-squares solution

约束矩阵方程问题；子矩阵约束问题；矩阵范数；最佳逼近解；最小二乘解

This paper considers nonlinear least squares problems,connecting new quasi-newton equations which has a higher-order curvature approximation with factorized quasi-newton method which is symmetric.

本文考虑非线性最小二乘问题，将具有更高的二阶曲率逼近的新拟牛顿方程和具有对称性的针对非线性最小二乘问题的分解方法结合起来。

On the other hand, the more important thing is because the urban housing is a kind of heterogeneity products.

另一方面，更重要的是由于城市住房是一种异质性产品。

Climate histogram is the fall that collects place measure calm value, cent serves as cross axle for a few equal interval, the area that the frequency that the value appears according to place is accumulated and becomes will be determined inside each interval, discharge the graph that rise with post, also be called histogram.

气候直方图是将所收集的降水量测定值，分为几个相等的区间作为横轴，并将各区间内所测定值依所出现的次数累积而成的面积，用柱子排起来的图形，也叫做柱状图。