The main differences between radiation angle and coverage angle are given, and the loudspeak′s directivity index is measured by two methods.
笔者对这些变化进行了解读,强调"辐射角"和"覆盖角"的区别,并用2种方法测量了扬声器指向性指数,从而说明新版标准中给出的用覆盖角计算指向性指数的方法简便易用。
It is considered that exponent of in power sum transform into the number of factor of algebraic expression which consist of n,r,x and d.
研究一类正负相间方幂和中素数因子p的指数问题,将方幂和中因子指数转化为由n,r,x和d组成代数式中因子个数计算。