The basic principle for determining the speed of moving vehicles with GPS Doppler observed values is discussed, and the available accuracy with this method is presented.
讨论了利用GPS多普勒频移观测值确定运动载体速度的基本原理，估计出采用这一方法可以达到的精度。
2
Conclusions Color Doppler ultrasonography can raise the accuracy of diagnosis in the occlusive arterial diseases of lower extremity.
结论彩色多普勒超声能帮助提高下肢动脉闭塞性疾病的诊断准确性。
3
In the displacement measurement system of scattering surface laser Doppler effect, the measuring accuracy is affected by the weakly Doppler signal that may be lost or discontinuous.