The very low frequency electromagneticmethod (VLF-EM) has such advantages as portable instrument, simple method, economical and high efficiency.
甚低频电磁法(VLF - EM)，具有仪器轻便、方法简单、经济高效等优点。
2
In transient electromagneticmethod (TEM) the real time detection of early signal requires the instrument to be fast time response, so a higher requirement is presented for the design of instrument.
瞬变电磁法实时检测早期信号要求瞬变电磁仪具有很快的时间响应，这就需对仪器设计提出很高的要求。
3
EH-4 continuous conductivity imaging system is a new generation digitalized electromagnetic-methodinstrument.