Automatic Recognition of Chinese Aspirated Sounds Pronounced by Japanese Students
Akemi Hoshino · International Journal of Computer and Communication Engineering · 2017
Chinese aspirates are usually difficult to pronounce for Japanese students.In particular, discriminating between the utterances of aspirated and unaspirated sounds is the most difficult to learn for them.For self-learning, an automatic judgment system was developed that enabled students to check their pronunciations using a computer.We extracted the features of correctly pronounced single-vowel bilabial aspirated sounds pa [p'a], pi[p'i], po[p'o], and pu[p'u] and unaspirated sounds of ba [pa], bi[pi], bo[po], and bu[pu] by observing the spectrum evolution of breathing power during both voice onset time (VOT), and the voiced period when uttered by 50 native Chinese speakers.We developed a high performance 35-channel computerized filter bank to analyze the evolution of the breathing power spectrum using MATLAB and automatically evaluated the utterances of 50 Japanese students.Using a high-resolution spectrogram, we closely examined the features in VOT closely and improve the criteria for a proper pronunciation.We applied our developed automatic recognition system with improved criteria to the utterances of the students, which passed the screening of native-Chinese speakers.Although our system rejected several samples passing the native speakers' screening, the success rates were higher than 95% and 98% for aspirated and unaspirated sounds, respectively.