Experiments of rock fracture verified that strong low frequency wave could be received both on the surface of rocks and in the air before the main fracture.

岩石破裂实验证实主破裂前在岩石表面和空气中均收到较强的低频波。

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When the defect of pile body is located at the range of one - dimensional blind areas, the wave form of the reflected wave distorts and shows the characteristics of strong amplitude and low frequency.

当桩身缺陷位于一维“盲区”范围时，反射波波形畸变，并呈强振幅，低频率之特征。

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Small size, good self-healing effect, low inductance, low loss at high frequency, strong over-current ability, and can withstand high current impulse.

体积小、自愈性好，电感量低，高频损耗小，过电流能力强，能承受瞬间大电流冲击。

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Although they have not been found to cause any harm, the cables on conventional pylons, which transmit a three-phase alternating current, generate a strong electric field and a continuous buzz of low-frequency radio waves.

ECONOMIST: Monitor