Using Fractal Dimension Analysis on Objective Auscultation of Traditional Chinese Medical Diagnosis
Speech variation is important for clinical examinations in auscultation of traditional Chinese medicine. This study applied continuous speech to compare the difference among sixteen qi-vacuity patients, nine ying-vacuity patients and twelve normal subjects. In order to compute the speech characteristics related to production irregularities, the fractal dimension (FD) parameter was used. Two sets of test sentences were spoken in Mandarin: one is specific design and the other is random choice. Each test sentence was pronounced three times as the test patterns, and then we compared the difference of complexity among them using the dynamic time warping (DTW) technique. The results revealed: (1) although the same sentence was read by each subject three times, the distributions of FD values each time were not exactly the same to each other; (2) no significant correlation was found between speech variations and syllables; (3) the utterances of test sentences of both qi-vacuity and ying-vacuity patients have much more variations than that of normal subjects; (4) good classification results (over 85%) were obtained using both sets of test sentences for the classification between deficient and normal subjects; (5) the classification accuracy using FD values of continuous speech was better than the results using five acoustic parameters of the vowel /a/ in our previous study. In conclusion, the fractal dimension analysis of continuous speech provides an alternative and outstanding approach to the objective auscultation of Chinese medical diagnosis.