For anyone that needs a little refresher course, the sine function gives the ratio of the opposite side of a given Angle in a right triangle to the hypotenuse.

一些人需要复习一点数学课程，正弦的作用是给出在一个直角三角形中的一个已知角所对应的一条边与直角三角形斜边之间的比率。

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This paper designs a Lissajous Figures signal generator which can generate sine wave with different ratio of frequency, By utilizing oscillograph, all kinds of stable diagram can be shown.

设计了一种利萨如图形信号发生器，能产生不同频率比的正弦信号，通过示波器能方便地得到各种稳定的利萨如图形。

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A practicable solution to the angle-digital conversion of synchro is provided, which includes cut section coding for the ratio of sine to cosine and sampling on double peak value.

针对自整角机的轴角数字转换，提出了分区间正余弦信号相比较编码和双峰值采样的方法。

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