The Chinese used a gravity meter to correct for local deviations in sea level.
中国人用重力仪来校正海平面的局部偏差。
2
The study was undertaken using a sound levelmeter operated by a passenger in each car tested.
研究用这样的方式进行：每辆接受测试的汽车的乘客开启声音强度测试仪。
3
Sensor in the horizontal adjustment process, it is best to use the levelmeter, making the installation of sensors in a unified horizontal plane, to ensure the consistency of the load they suffered.