声纳位差修正量
sonar parallax correction
声电位差
psophometic potential difference
psophometric voltage
上下游水位差
hydraulic gradient between upper and lower reaches
扫描像位差
scan positional distorton
轮位差
Positioning Errors of Wheel
料位差
Material Level in existence
跨步电位差
step potential difference
库区大水位差
Large Water Fluctuations in Three Gorges Reservoir Area