曲面

Peaks(30); N=16;% number of contour lines and their colors clf % clear the current figure view(3)% set view to 3-D hold on % hold blank screen setgca,' ColorOrder ',hsv(N % use colors from default hsv colormap contour3 % draw N contour lines grid,xlabel(' X-axis '),ylabel(' Y-axis '),zlabel(' Z-axis ') title(' CONTOUR3 of PEAKS ') hold off

输出见图 18.17。图 18.17 函数 PEAKS 的三维等值线图现在，各条等值线的颜色沿着 z 轴的变化和网格图曲面图网格图和曲面图网格图曲面图一样。

The spacing triangulation was achieved by restricting the angle between two adjacent triangle's normals, which can decrease or increase the data efficiently, varying with the surface's curvatures, added to the optimizing local triangulation, and uniform and smooth triangulation are obtained.

该方法从插值曲面的形状变化来考虑，根据空间离散点曲面的曲率变化有效地剔除或增加离散点，实现了离散点曲面的疏密三角网格划分。

A new digital measure method was presented based on the three coordinate measuring machines. Compensation of sensor radius, establish part's measure reference frame, the best measuring layout and mix programmed scanning all those not only enhance measure precision and increase efficiency of scanning measure, but also the data can image geometrical characteristic of complex surface. The method was illuminate by a sample, and the digital data of the surface adumbration are obtained at last

在三坐标测量机的基础上给出了一种数字化测量曲面轮廓的方法，通过测球半径的补偿、坐标系的建立、最佳测量路径的规划以及混合编程扫描，提高了测量精度及扫描测量的效率，而且采集到的数据可以反映曲面的几何特征，并以实例对该方法进行说明，得到了数字化的曲面轮廓数据。

So it is not easy to turn this idea into reality. We creatively give our parameterization by using the expression of the blending surface in affine coordinate system ([9]) and the plane pencil together.

在仿射坐标系下，二次有轴曲面的表达式相对简单，我们基于厉玉容[9]给出仿射坐标系下拼接曲面的表达形式、不分块直接对混合拼接曲面进行参数化。

This paper proves that the rolling sphere surface determined by two algebraic surfaces is also an algebraic surface.

摘要证明由两代数曲面所确定的滚球曲面仍是代数曲面。

The meaningful regions obtained by range image segmentation correspond to the surface patches of 3D object.The 3D surface patches are then reconstructed by the algebraic surface fitting method;the surface parameters are estimated by solving generalized eigenvector problem. The geometric model of 3D object is constructed from reconstructed surface patches by using CAD geometric modeling tool GEOMOD.

首先通过编码光栅方法获取三维物体的深度图象，并采用数学形态学的方法加以分割，然后利用代数曲面拟合手段对分割后的三维曲面片进行重建，并使用CAD几何建模工具由重建的曲面片构成物体的几何模型。

If the surface isrepresented by an implicit algebraic equation,the mapping can be constructed bythe theory of parametrization of algebraic surfaces;If the surface is represented byan parametric equation,the parameter values on the parameter plane can be solvedby numerical method or Grobner Basis method.

若曲面由代数隐式方程给出，可通过代数曲面参数化理论构造映射；若曲面由参数方程给出，可通过数值方法或Grobner基方法求解参数型值点。

PROJECT_ON_DRIE_SURFACE—Preseres the lead angle of the tool axis relatie to the surface normal for each explicit axis defined at locations on the surface.

投影在驱动曲面上–保留刀具轴相对于在曲面的多个位置处定义的每个显式轴的曲面法向的导引角。

On the basis of OCM, segmentation based on curvature radium is presented in the paper, in which curvature radium is calculated using parametric-surface fitting, and detecting edge points is realized from orthogonal direction, which ensure the integrality of edge points. Since the data is organized by cross-line in OCM, a new arithmetic, Double-direction Angle Difference arithmetic, is brought forward, which can pick up edge points more quickly.

物体的表面一般由多个曲面相交组成，要建立完整的几何模型，需要对测量数据进行区域分割——区分不同曲面的数据，现有的区域分割大多是对单视图的图像式测量数据进行的，但完整的CAD模型需要联合多个视图产生，本文在上面提出的三维正交模型的基础上，提出了三种区域分割方法：第一种方法是基于曲率半径的数据分区方法，通过二次参数曲面拟合计算局部曲率半径，从正交的多个方向进行检测，保证了边点提取的完整性。

On the basis of analyzing the theory of the modeling of the propeller surface, this paper transforms the section data given by design to the data in Descartes coordinates. Interpolates the section data to get enough data and fits the blade surface with the least square method. A perfect C2 blade surface can be obtained by adjusting the deviation weight and fairing weight. According to the cylinder rough, two rough cut methods are preferred.

本论文在深入分析螺旋桨曲面成型原理的基础上，将设计时给定的桨叶曲面的切面数据转化为笛卡尔坐标系中的坐标，利用B样条方法对截面数据点插值并加密，得到足够的数据点，进而利用最小二乘法拟合出桨叶曲面，通过调整偏离权和光顺权得到了理想的二阶连续的桨叶曲面。

I didn't watch TV last night, because it .

昨晚我没有看电视，因为电视机坏了。

Since this year, in a lot of villages of Beijing, TV of elevator liquid crystal was removed.

今年以来，在北京的很多小区里，电梯液晶电视被撤了下来。