当事情变得艰难时，我们就会看到警告标志和信号。

We see the warning signs and signals when things get rough and difficult.

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SCAT-1航空电子设备利用接收到的信号，来改善沿着确定的飞行路径的位置精确度和信号集成度。

SCAT-I avionics uses the received signal to improve position accuracy and signal integrity along a defined flight path.

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眼神可以在讲话或者结束，甚至在表达厌恶的时候传递情绪和信号。

It can convey emotion, signal when to talk or finish, or aversion.

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But in hard drives where we actually have these moving platters, here is in fact, how we get from electricity and magnetism to those zeros and ones.

但是在传统硬盘中我们确实有高速运转的磁盘，这就是事实，但问题是我们如何,把电磁信号转化为0和1的。

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And,you may or may not be intested in the motion, as I am, but you might say: what is the signal good for?

对于情感来说，你们或许有兴趣，也有可能和我一样觉得没意思，但你会问，这种信号什么用处？

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So this is not a very positive sign and people are having a bad relationship with food.

这不是个正面的信号,人们和食物之间的关系变糟

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