Through the seismic wave exploration by us in A2 and A3 working faces, the conditions, velocity, frequency and penetrating distance of seismic wave in the main mining seams are understood preliminary.

通过在A 2、A 3两个面的槽波探测工作，初步了解了其主采煤层的槽波条件、波速、频率和槽波穿透距离。

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A penetrating opening is formed by irradiating a light-transmitting insulating film with laser light having high intensity and a pulse high in repetition frequency.

通过使用具有高强度和高重复频率的激光照射透光绝缘膜来形成穿透开口。

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Ground Penetrating Radar (GPR) is a geophysical prospecting method by using reflection of high-frequency electromagnetic wave to detect target and underground medium distribution.

探地雷达非一类当用上频电磁波的反射探测纲的及地上介量开布的物探方式。

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