关键词: 振动与波, 炭素电极, 敲击, 检测机理, 小波, 粗糙集

Abstract: Wavelet and rough sets are used to analyze the detection mechanism of cointapping response signals from carbon electrodes. After 8 layers decomposition of the response signals using db9 wavelet basic function, 9 wavelet channels are obtained. Then, rough sets are used to delete the redundant character channels in the 9 wavelet channels. The results show that channels D5, D6, D7 and D8 are the effective character channels to distinguish defective electrodes from quality electrodes. Furthermore, research on detection mechanism shows that the difference of cointapping response signals between defective and quality electrodes is distinguished from the difference of resonance phenomena in base frequency and low order harmonic wave. In addition, an effective method for binary attribute importance analysis, which can delete redundant attributes with null importance in pairs, is proposed. And the core of knowledge expression system can be found with this method.

Key words: vibration and wave, carbon electrode, cointapping, detection mechanism, wavelet, rough sets