桑原尚夫,武田一哉
日本語孤立発声単語における母音無声化の分析と予測
Abstract:An analysis of vowel-devocalization in Japanese is
presented as a method of finding general rules for allophonic
variations of phonemes in continuous speech, i.e.to find quantitative
relationships between phoneme environments and allophonic
variations. A speech database consisting of about 5,000 common
Japanese words spoken in isolation by a professional male announcer
was used. The database used is part of a large-scale speech database
that is now being compiled and hand-transcribed at several levels of
phonetic detail. Based on the acoustic-phonetic transcription of the
speech data, factor analysis of the phonetic environment was
performed for the devocalized vowels. The results reveal that the
influence of the immediately following phoneme on devocalization is
the greatest of the four factors examined. The second most important
factor is the position of the accent nucleus. Automatic prediction of
vowel devocalization is discussed using the results of this analysis.