In this paper, the control points are calculated based on the curve or surface's data points and the knot vector which is calculated with four kinds of parameterization by the method of NURBS.

文中根据曲线曲面型值点，分别用四种参数化方法构造节点矢量，利用NURBS方法反算控制点。

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If the end points of both objects already coincide, they are simply joined together with a multi - knot.

如果两者间已经相叠，两者将会用无数的结点简单连结。

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A necessary and sufficient condition is derived for the existence of monotone and convex interpolation by a cubic spline with an additional knot inserted between each pair of data points.

本文给出用三次样条在两两节点之间引进一个外加节点的条件下，存在凸而单调的插值的充分必要条件。

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Katz also seemed tie himself in a knot with the juxtaposition of two points that he himself made: first, he emphasized that the vast majority of innovative ideas and technological breakthroughs are coming out of American cities and major metropolitan areas probably more than 85%, he said.

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