离心泵轴承磨损一般与()无关。
A. 对中偏差大
B. 轴弯曲
C. 润滑油质量差
D. 人口压力
对称三相电源指的是各相电压大小_____,频率______,相位______
单词互译:( )geodeticcontrolpoint:( )地形图:( )constructionmap:( )平面测量:( )高程测量:( )控制点:( )控制网:( )控制测量:( )碎部测量:( )
单词互译:inertialsurveying:( )大地测量,大地测量学:( )geodetic surveying :( )geodetic network:( )矿山测量学:( )工程测量:( )cadastral surveying:( )Topographicsurveying:( )differentialGlobalPositioningSystem(DGPS):( )