부산대학교 도서관

An algorithm for pitch frequency measurement for pattern detecting systems of borderline mental disorders is developed. The essence of the algorithm is decomposition of a speech signal into frequency components using an adaptive method for analyzing of non-stationary signals, improved complete ensemble empirical mode decomposition with adaptive noise, and isolating the component containing pitch. A block diagramfor the developed algorithm and a detailed mathematical description are presented. A research of the algorithm using the formed verified signal base of healthy patients, and male and female patients with psychogenic disorders, aged from 18 to 60, is conducted. The research results are evaluated in comparison with the known algorithms for pitch frequency measurement, realized on the basis of the autocorrelation function and its modifications, the robust algorithm for pitch tracking, and the sawtooth waveform inspired pitch estimation. In accordance with the results of the study, the developed algorithm for pitch frequency measurement provides an accuracy increasein determination of borderline mental disorders: for the error of the first kind, on the average, it is more accurate by 10.7%, and for the second type error by 4.7%.