奈奎斯特准则提供了一种图形方法来确定闭环系统的稳定性。

The most important thing is to be sincere in what you do. If you are sincere, the public will feel it.

"The past is always with us, but it doesn't have to define our future."

史记

The land remembers, even when people forget.

诗歌是暗示的艺术，而非断言的艺术。