This article is to illustrate that the conic section is an envelope of family of straight lines, thus we discover the internal relations between the conic section and the solution of differential equation.
对圆锥曲线是直线族的包络进行了证明,揭示了圆锥曲线与微分方程的解之间的内在联系。
It is proved that the surface organized by all the straight lines which are coplanar with three u-family rectilinear generators of an uniparted hyperboloid,which are not coincident with each other,is exactly the primal uniparted hyperboloid.
证明了与单叶双曲面上3条互不重合的u族直母线均共面的直线所构成的曲面正好是原单叶双曲面。
Lines are selected by neighborhood-rule or window-rule to compute projective invariants.
在所得直线族中按照邻近规则或者窗口规则挑选直线计算投影不变量。
This article is to illustrate that the conic section is an envelope of family of straight lines, thus we discover the internal relations between the conic section and the solution of differential equation.
对圆锥曲线是直线族的包络进行了证明,揭示了圆锥曲线与微分方程的解之间的内在联系。
These are two families of straight line, known as the characteristic lines.
这是两族直线，叫做特征线。
The Direct Perturbation Method and Approximate Solutions of Nonlinear Schr(?)dinger Equation Hierarchy;
直接微扰方法和非线性薛定谔方程族的近似解
Study of On-machine Measuring Principle and Technology of Large Gear Based on Straight Generatrix Family Deviation;
基于直母线族偏差的大齿轮在机测量原理与技术研究
To arrange in or form a line.
排成直线，形成直线
Line ab be twice longer than line cd .
直线AB比直线cd长2倍。
a straight road, line, rod
直的路、 线、 杆
in alignment (with...)
(与…) 成一直线
Of, relating to, or resembling a line; straight.
线的，直的线的、与直线有关的或象直线的；直的
In a vertical or perpendicular line.
垂直地在一条垂直线或竖直线上
draw a line perpendicular to a given line
作一直线与已知直线垂直
Arrangement or position in a straight line or in parallel lines.
直线排列直线或平行线的排列或位置
In, of, describing, described by, or related to a straight line.
直线的直线本身的、直线的、描述直线的或用直线描述的或与直线有关的
A vertical or nearly vertical line or plane.
垂直线，垂直面垂直或近似垂直的线或平面
DRDRAM Direct RAMBUS DRAM
直接内存总线DRAM
straight-in approach
(飞机) 直线进场
out of alignment (with...)
(与…) 不成直线的
