查询词典 least squares

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。

Then, on the basis of Atluri's work, a modified MLPG method is employed, in which the moving least squares approximation is used as a trial function and the Heaviside function is used as a test function of the weighted residual method.

然后基于Atluri等人的工作，采用移动最小二乘近似函数构造试函数，采用Heaviside函数作为加权残值法中的权函数，采用直接插值法施加本质边界条件而不采用罚函数法和拉格朗日乘子法。

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

For the sake of decrease of the computing time, modifying generalized moving least squares approximation is constructed under adding the residual of arbitrary high orders derivative only at the portion nodes.

为了降低计算工作量，构造了要求近似函数在全部节点处和任意阶导数在部分节点处误差的平方和最小的改进广义移动最小二乘近似。

For the sake of decrease the computing time, modifying generalized moving least squares approximation was constructed under adding the residual of high orders derivative only on the portion nodes.

为了降低计算工作量，本文构造了要求近似函数在全部节点处和任意阶导数在部分节点处误差的平方和最小的改进广义移动最小二乘近似。

For this purpose, the compactly supported radial basis function and the moving least squares approximation based ones are integrated into the aforementioned two global optimizers. As a result, two novel hybrid algorithms are introduced.

其次，为解决电磁场逆问题分析、计算中由于随机类优化算法需进行数以千计次电磁场的数值分析，以致计算时间和计算量难以满足工程分析实际要求的难题，本文将表面响应模型法引入电磁场逆问题的求解，研究了基于紧支径向基函数和基于移动最小二乘法的两种表面响应模型，并将其分别与改进的遗传算法和粒子群算法相结合，提出两种不同的混合快速全局优化算法。

The technique of perturbations constraint when applied to degree reduction of Bézier curves gives fairly well results This paper discusses why these kind of technique have limitation when applied to B-spline curves, and the least squares approximation approach is presented for reducing the degree of B-spline curves Examples comparing the new method with existing ones are illustrate

将扰动约束技术应用于B啨zier曲线的降阶给出了理想的结果讨论了将这类方法应用于B样条曲线降阶时结果不理想的原因，提出了采用最佳平方逼近技术对B样条曲线做降阶运算的方法；并用实例对该方法和基于扰动约束的降阶方法进行了比

Combining the modified variational principle functional with the Moving Least Squares approximation, the HBNM involves three types of independent variables, i.

杂交边界点法将修正变分原理与移动最小二乘法结合起来，涉及三类独立的场变量。

By coupling the moving least squares approximation with a modified functional, the Hybrid Boundary Node Method is a boundary-only, truly meshless method.

中文摘要：杂交边界点方法是一种纯边界类型的无网格方法，它将修正泛函和移动最小二乘近似结合。

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。

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。