in this paper we propose a method of projective transformation from pitch surface to cutter surface for studying face mill cutters.

文中借助于形象思维把齿轮的啮合几何化，提出了一种研究按滚切法工作的切齿刀具的方法，从节曲面到齿曲面的射影变换。

theweights are characteristic values of the projective transformation (with a constant factor).

权系数是此射影变换的特征值（差一常数因子）；

projective transformation and affine transformation are essential in the image transformation.

仿射变换和透射变换是两种基本的图像变换。

basic composition of models is projective transformation from multi-dimensional allocation to bivariate distribution.

模型的基本结构是一个从多维到低维的投影变换。

the projective transformation and lens-distortion parameters are computed simultaneously with the nonlinear optimal method.

用非线性优化技术对投影变换和径向畸变校正参数同时迭代优化求解。

this paper presents a method of arc projective transformation of the fundamental geometric elements on a sphere, and sets up an are projective system for three axial and two axial correspondently.

本文提出了一种球面上基本几何元素的园弧投影变换方法，并建立了三轴及对应的二轴园弧投影体系。

using the relationship of the projective transformation between 3d points and 2d points, the translation and the rotation angle can be computed.

根据计算机视觉成像原理，利用三维点到二维点的投影关系，可以计算出摄像机相对世界坐标系的平移和旋转参数。

the advantages of the method of calculating the orthographically projective transformation are concluded.

③简要分析这种计算方法的特点。