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Modeling of plosive to vowel transitions

Beköz, Alican
This thesis presents a study concerning stop consonant to vowel transitions which are modeled making use of acoustic tube model. Characteristics of the stop consonant to vowel transitions are tried to be obtained first. Therefore several transitions including fricative to vowel transitions are examined based on spectral and time related properties. In addition to these studies, x-ray snapshots, lip videos and also experiments including subjects are used to intensify the characterization, from the production and the perception side of views. As results of these studies the plosive to vowel transitions are observed to be uttered by exponential vocal tract movements and the perception mechanism is observed to be highly related with exponential spectral changes. A model, based on the acoustic tube model, is tried to be established using the knowledge and the experience gained during characterization therefore proposed model involves the vocal tract parameters observed in characterization part. Finally, plosive to vowel transitions including three types of plosives (alveolar, labial and velar) are synthesized by the proposed model. The formants of the synthesized sounds are compared with the formants of the natural sounds. Also the intelligibility tests of these sounds are done. Performance evaluation tests show the proposed model’s performance to be satisfactory.