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。
我不是一个回头看的人，我总是向前看。
The mind is a system of organs of computation, designed by natural selection to solve the kinds of problems our ancestors faced in their foraging way of life.
"To read is to travel without moving, to live a thousand lives in one."
"The past is always tense, the future perfect."
如果你没有失败，说明你不够努力。
Small-scale fishers and farmers are the unsung heroes of sustainable aquaculture.