The vital capacity is a breath biggest ventilationquantity, in a sense may reflect the breath function potential power.
肺活量是一次呼吸的最大通气量，在一定意义上可反映呼吸机能的潜在能力。
2
The density control of gas and coal dust is done through optimal allotment of the ventilationquantity in the coal mine well.
煤矿井下瓦斯和煤尘的浓度控制是通过煤矿井下通风量的优化分配实现的，是实现煤矿安全生产的关键环节。
3
In case of meeting the dust collecting efficiency of the system, the economical ventilationquantity was determined making the system to be operated under economic condition.