Zero-crossing detector is capable of predicting the shape changes of power spectrum so as to find the newly emerged moving sound sources in ambient noise.

过零检测器可以通过预报功率谱形状的变化来发现环境噪声中新出现的运动声源，研究了过零检测器的检测性能。

youdao

Suzhou Apache's electric car with zero emission, low noise, good power and operational performance and charging facilities, the use of low-cost features.

苏州阿帕奇电动车有限公司的电动汽车具有零排放、低噪音、良好的动力性和操作性能及充电便利，使用成本低的特点。

youdao