A relaxation technique for seeking optimal vowel candidate sequence

A relational model for Japanese vowels is defined that describes the relations among vowels using only relative parameters. Based on the model a new approach for vowel recognition is developed in which three candidates are considered for every vowel in a vowel sequence and each candidate sequence is evaluated as a whole by checking the relationships among them. We show a relaxation algorithm in this paper to seek the optimal candidate sequence from a large quantity of candidate sequences. The approach has been applied to a large speech data base consisting of spoken words voiced by 84 speakers. Experimental results show that the technique is highly effective for speaker-independent recognition of vowels.