Roles of dynamic patterns of lower formants, vowel identity, and gender in predicting postvocalic consonant place in Korean spontaneous speech

초록

A neural network model was trained and tested on various temporal lower formant frequencies sampled at 10% intervals from the vowel offset backwards to the target to predict the postvocalic place (bilabial, alveolar, palatal, or velar) in XVC tokens in Korean spontaneous speech in Seoul Corpus. Performance of the model, trained on F2 samples taken doubly at the vowel offset and target or at 70-80% of the vowel duration and target, performed robustly better than F2 samples taken singly at the offset. Vowel identity, temporal F1 and F3 samples served to disambiguate places with ambiguous F2 transitions more than gender, suggesting that gender normalization was not essential in the present model. Compared to the work on model prediction of prevocalic place from vowel tokens in Seoul Corpus in Hong (2022), postvocalic consonants exerted slightly stronger coarticulation resistance over vowel signals than prevocalic consonants. Furthermore, the contribution of vowel category information as an additional predictor was substantially smaller in model prediction of postvocalic place than prevocalic place, which was attributed to vowel neutralization in the time course of vowel articulation toward the vowel offset.

키워드