The results show that as the voltage (friction), pressure (frequency) changes, there is a best combination between the two values. The control effect of acceleration is better than displacement.

结果表明，随着电压(摩擦力)、气压(频率)的变化，两者的取值存在最优的组合，并且加速度的控制效果略好于位移的控制效果。

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The friction caused by the gas bubble pushing up the pipe and displacing the drilling mud used to control the pressure could have created a static charge that ignited the gas into a fireball.

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