A recursive formula for orthogonal projections and its application to the least squares problem are introduced in this paper.
本文介绍一个计算直交投影的递推公式，并介绍如何用其求解线性最小二乘问题。
In this paper, a new approach to reconstruction of transverse cross sections of arteries from biplane orthogonal projections is proposed.
提出了一种利用双平面正交投影重建血管截面的方法。
The four aspects is as follow:(1) Modelling a free curved surface from the orthogonal projections and the normal vectersof controlling points.
这四个方面分别是：（1）已知数据点的正投影和曲面上数据点处的法线方向，构造自由曲面；
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