The story has a number of variants, different people talking to a taxi driver, lift operator etc. The basic point is still valid though.
关于擦鞋男孩的这个故事有若干种不同版本，不同的人是在与出租车司机、电梯操作员等进行交谈时发现股市处于泡沫的，然而，其基本思路都是站得住脚的。
The basic principle of eddy current testing is introduced and the coil impedance responses due to the variations of the probe coil lift-off are analyzed and studied.
简要介绍了涡流检测的基本原理和涡流探头的特性； 分析和研究了涡流检测探头提离变化对阻抗的影响；
The potential lift is computed by the numerical method of basic solution distribution.
位流升力的计算，采用基本解的数值计算方法。
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