When shake reach to some intensity in some direction, frequency and extent, people will have serious bad reaction.
当震动在一定方向和频率、幅度内达到一定强度时，会导致人体产生较严重的生理不良反应。
2
The pure quartz shake circuit with a high stable performance to the frequency.
全部采用石英振荡电路，具有极高的频率稳定性能。
3
The circumstances and headway in probe job of near technique around blast shake safety are given. The technical make use of control principle about frequency spectrum property.