In this paper, errors of digital levels are introduced. Calibration methods of the collimationerror and the system accuracy are presented.
分析了数字水准仪系统的误差源，阐述了仪器i角误差和综合精度的检定方法。
2
Besides, artists produce the mobility of fresco by means of structure of "Tendentious Tension", collimationerror, and psychological effect.
此外艺术家通过画面“倾向性张力”结构、视错觉、心理感受等手段使壁画产生流动感。
3
Firstly, the velocity of target was educed from the secondary calibration to correct the collimationerror, and the incorporated wind speed was introduced to simplify the model of fire control.