Steam generator level is a non-linear, mutative and multi-variable system. It is a problem to design the control system because of "false level".

蒸汽发生器水位控制系统是非线性、时变的多变量系统，“虚假液位”现象的存在使蒸汽发生器液位控制成为一个难题。

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Fido can pick up the smell of TNTvapor at concentrations of just a few parts per trillion, and it was the first sensor to find buried mines at a level comparable to dog performance, with a false-alarm rate of less than 5%.

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But with improved protection from equipment such as ski body armor, is there a danger of being lulled into a false sense of security and to attempt something above your ability level?

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"It suggests a level of criminality which to my mind could easily extend to exploiting criminal connections to obtain false travel documents and leave the country undetected, " he added.

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