all things in the universe, whether stone, plant or human, vibrate at their own specific frequency . it is precisely because of this difference in frequency that it is difficult for animals and humans, humans and humans, and even husband and wife, to communicate with each other 宇宙万物都会振动,它们各自都有不同的振动频率,不管是石头草木人等等,都有它们特殊的振动频率,正因为振动频率各自不同,所以动物和人之间,人与人之间,丈夫和太太之间,都很不容易沟通。
the 45 steel samples, which were treated by different heating and cooling methods, were tested and the testing signal were analyzed elementarily in frequency domain using the program . the results show that for the ultrasonic testing signals of different microstructure, the difference in frequency domain is distinguishable 论文还运用所编制的分析软件,对不同热处理状态下的45钢超声检测信号进行了初步的谱分析,结果表明不同金相组织的超声检测信号频谱有明显不同。