As you can see in Figure 1, the human voice produces a distinct average of characteristic frequencies when speaking.
如图1所示，人类语音在说话时将生成独特的平均特征频率。
2
This paper describes the signal characteristic in optical fiber communication systems, and the way to set the signal levels appropriately for the minimum average error rate.
本文阐述光纤数字通信中部分响应信号的特点，和适当地设置信号电平使平均误码率达到最小的方法。
3
This paper discusses average approximation and proposes four theorems which are the supplement for existence theorem, characteristic theorem and solitariness theorem.