查询词典 first approximation

In this paper we discuss the optimal approximation of matrices and its numerical algorithm on some closed convex cone .

讨论矩阵在闭凸锥上的最佳逼近及其数值算法，在对称半正定矩阵集上，给出了最佳逼近数值算法的MATLAB程序和数值例子。

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

Digital holography ; Microscopic digital holography ; Wave front reconstruction ; Fresnel approximation ; Convolution method ; Angular spectrum theorem

数字全息；显微数字全息；波前重建；菲涅耳近似；卷积法；角谱方法

In order to apply virtual reality technique into medical image processing, make convenient for surgeons to access virtual and mini invasive surgery, this paper, presents a full interactive virtual endoscopy system framework, analyzing and discussing system architecture and algorithm models. We explain some key procedures in virtual endoscopy system such as definition of world coordinate, virtual camera, surface detection, normal approximation, volume rendering and surface rendering, and also some interactive control method.

在综合利用各种计算机图形、图象技术的基础上，提出了完整的交互式虚拟内窥镜系统的框架，同时对系统结构和各种模型进行了分析和讨论，还针对系统的实时性和绘制结果的逼真性要求，提出了基于 Object Cache和扩展的区域增长方法，并将其应用到医学图象处理当中，得到了较好的效果。

The numerical results indicate that the generalized Dirichlet distribution should be a reasonable prior, and the computation in forecasting coproduct output is relatively straightforward with respect to the approximation approach.

本研究所採用的贝氏统计分析方式，对於预测生產量的计算，比求近似解的方法简单，可计算变数二阶以上的动率，而且在使用的时机上较不受限制。

The obtained results suggest that for weakly correlated random variables such as two instances of a self-similar process with a long time lag, half the square of the correlation coefficients might be a reasonable approximation to the mutual information.

本研究的结果建议，对於弱相关的随机变数，如一个自我类化过程中具有长的时间差的不同二个时刻的值，相关系数的平方值的一半似可作为交互讯息的一个合理的近似。

After briefly reviewing the classification and history of curve and surface modeling, we discuss the characters, applications and representative work on three types of geometric approximation. And we present a survey of the vertex correspondence problem and the vertex interpolation problem in 2D and 3D shape blending modeling and key frame animation.

作者简要回顾了曲线曲面造型的分类和发展历史，论述了曲线曲面造型中所遇到的三类几何逼近问题的特点、应用和代表性工作，并就用于二维和三维形状混合造型的几何插值方法从顶点对应和顶点插值两方面做了一个系统的综述。

The problem of polygon approximation was formulated as one of minimizing cost function.

1引言多边形近似算法是物体形状识别的重要方法。

Tsang has made a reseach on the approximate operator in covering approximation space, and proposed a more reasonable covering rough set model.

Tsang对覆盖近似空间中的近似算子进行了研究，提出了一种较已有模型更合理的覆盖粗糙集模型。

A projection method is used to smooth out start and end points of the ruling line sets. With predefined Euclidean 6 space distances, the problem of ruled surface approximation from line sets in Euclidean 3 space can be converted into a least square B-spline curve fitting issue in Euclidean 6 space.

利用"投影"光顺法对齐直母线段族首末端点，再通过定义欧氏6空间下的距离函数，将欧氏3空间下的直线族逼近直纹面问题转换成欧氏6空间下B样条曲线最小二乘拟合问题。

For the head-teacher of the class said that I had seriously broken the school rules,which led me to a three-day suspend class.

为什么呢？因为我的班主任说我严重的违反了校规，于是让我停课三天。

Many of them believe that the conversion of thousands of working-class folk in England spared that nation from the mass carnage and the tyranny that came with the revolution in France.

他们之中有许多人相信，在英国数以千计的劳工阶级之悔改信主使英国免於遭受如法国大革命所造成的大屠杀和专制暴政。