Two Point One Line的意思|示意

The two elements of a lower pair have theoretical surface contact with one another, while the two elements of a higher pair have theoretical point or line contact (if we disregard deflections).

这两个因素中的低副是两个理论表面之间的接触，而这两个因素中的高副是理论的点或线接触(如果我们忽视了挠度)。

A one-to-one correspondence between the points on two lines determined by a given point, not on either line, called the center of perspectivity or point of perspectivity.

由一给定点确定的、两条直线上的点之间的一一对应，该给定点不在这两条直线上，称为透视中心或透视点。

Contrasting the waves reflected from the fault line and the normal one, and subtracting this two waveforms, then the fault distance is determined by finding the first distortion point.

比较故障线路和正常线路波形，使两波形相减，利用波形差第一个畸变点来确定故障距离。