曲面族

According to the equation of asymptotic curves, a family of nonlinear asymptotic curves are given to the principal normal surface.

根据渐近曲线的方程，具体给出主法线曲面的一族非直线的渐近曲线。

Mathematics A set of functions or surfaces that can be generated by varying the parameters of a general equation.

族：通过改变一般等式的参数形成的函数或曲面

We also define two families of functions, named a torus height functionand an AdS-distance-squared function respectively, and use them to investigate thesingularities of the AdS-null surfaces and the torus Gauss images as applications ofsingularity theory of functions.

作为函数奇点理论的应用，利用这两个函数族来研究AdS-null曲面和环面高斯像的奇点。

Proposition 2 Suppose that cyclic surface S is foliated by pieces of circles lying in parallel planes,and ?

命题2如果S是由位于平行平面里的单参数圆族生成圆纹曲面，且满足？

Breath, muscle contraction of the buttocks; arch body, as far as possible to hold his head, right leg straight towards the ceiling (peg-leg knee in order to avoid muscle tension).

呼气，收缩臀部肌肉；拱起身体，尽量抬起头来，右腿伸直朝向天花板（膝微屈，以避免肌肉紧张）。

The cost of moving grain food products was unchanged from May, but year over year are up 8%.

粮食产品的运输费用与5月份相比没有变化，但却比去年同期高8％。