Several units calculate the UHV transmission line shielding failure trip ratio with the leader propagation model (LPM).
国内外也有多个单位研究使用先导传播模型（LPM）计算特高压线路雷电绕击跳闸率。
2
In order to improve conventional GMAW process the effect of shielding gas quality and mixed ratio of different gases on welding quality are studied and useful fixtures are developed.
为提高常规气电焊工艺水平，进行了保护气体质量及配比对焊缝质量影响规律的研究及气电焊辅具的研制。
3
The signal-to-noise ratio of the silicon capacitance microphone is improved, and the shielding effect is favorable.