Wolfgang Wokurek

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This paper investigates the influence of different types of disturbances to the estimation of voice quality parameters. Here, voice quality is not only based on the pitch or pitch contour as in many approaches. The parameters are estimated by spectral gradients of the vocal tract compensated speech signal. We present a set of five parameters for describing(More)
It is difficult to recognize accented or non-native speech with speech recognition systems that are trained using native speech. While standard acoustic speaker adaptation techniques are often applied in these cases, they can only reduce the recognition errors that are due to mispronunciations on the phoneme level. They are not able to handle severe(More)
We address the possibility of combining the results from hemodynamic and electrophysiological methods for the study of cognitive processing of language. The hemodynamic method we use is Event-Related fMRI, and the electrophysiological method measures Event-Related Band Power (ERBP) of the EEG signal. The experimental technique allows us to approach the(More)
In this study Hidden Markov models are employed for the automatic classiication of pitch accents in German utterances. A sim-pliied version of the tone sequence model (i.e. a linguistic theory of pitch accents) is applied. In this approach only two of the nuclear tones (rise, fall) are used. They are represented by continuous density Hidden Markov models.(More)
We present a non-invasive attempt to indirectly measure the subglottal sound pressure. This quantity opens an additional acoustical path to observe the voiced sound source. The subglottal sound pressure contours of two phonation qualities, the modal phonation quality and the breathy phonation quality, are compared. The electroglottographic signal was(More)
Acoustic and electroglottographic (EGG) measurements were used to examine voice quality parameters during the production of the rising and falling pitch movements in German. The vowels / / and / / were studied in a single-speaker speech corpus. The acoustic measurements comprised an automatic spectral analysis of the glottal parameters open quotient (OQ),(More)
The current version ACCV4 of our acceleration sensor device is presented and used to study the influence of vowel duration to the estimates of resonances of the subglottal system of 7 female and 9 male speakers. The sensor records movements in all three spatial directions below 5 kHz. It is gently pressed to the neck of the speaker in front of the(More)
We address the possibility of combining the results from hemodynamic and electrophysiological methods for the study of cognitive processing of language. The hemodynamic method we use is Event-Related fMRI, and the electrophysiological method measures Event-Related Band Power (ERBP) of the EEG signal. The experimental technique allows us to approach the(More)
Wolfgang Wokurek Institut f ur Maschinelle Sprachverarbeitung Universit at Stuttgart, Azenbergstra e 12, 70174 Stuttgart, Germany wokurek@ims.uni-stuttgart.de ABSTRACT Simultaneous recordings of the laryngograph signal and speech recorded in an non-reverberating environment are investigated for acoustic evidence of the glottal opening within the(More)
This study compares manual measurements of the first two subglottal resonances to the results of an automated measurement procedure for the same quantities. We also briefly sketch the sensor prototype that is used for the measurements. The subglottal resonances are presented in the space spanned by the vowels’ first two formants. A three axis acceleration(More)