Computer-aided analysis of acoustic emission signals accompanying methyl polymetacrylate degradation in a strong electric field

The paper presents the results of frequency and time-frequency analyses of the acoustic emission signals arising during degradation of methyl polymetacrylate in a strong electric field. The frequency analysis was carried out with the use of Fourier Fast Transform method (FFT), while the time-frequency analysis - with the use of Short-Term Fourier Transform (STFT). The MatLafa software package was used for purposes of analyzing. It was found that the acoustic emission signals measured this way include some predominant frequencies. Results of the studies have shown that in the considered frequency range of the acoustic emission signals (0÷96kHz) the part of the signals of frequencies CH-15kHz and 43÷53kHz predominated.