• Volume/Page
  • Keyword
  • DOI
  • Citation
  • Advanced
   
 
 
 

Journal of the Acoustical Society of America

BROWSE VOLUMES

Year Range: 
Search Issue | RSS Feeds RSS
Previous Issue

Jun 2006

Volume 119, Issue 6, pp. 3493-EL73

Return to All Sections
back to top
RSS Feeds

Simulation of vocal fold impact pressures with a self-oscillating finite-element model

Chao Tao, Jack J. Jiang, and Yu Zhang

J. Acoust. Soc. Am. Volume 119, Issue 6, pp. 3987-3994 (2006); (8 pages) | Cited 22 times

Full Text: Read Online (HTML) | Download PDF

Show Abstract
Vocal fold impact pressures were studied using a self-oscillating finite-element model capable of simulating vocal fold vibration and airflow. The calculated airflow pressure is applied on the vocal fold as the driving force. The airflow region is then adjusted according to the calculated vocal fold displacement. The interaction between airflow and the vocal folds produces a self-oscillating solution. Lung pressures between 0.2 and 2.5 kPa were used to drive this self-oscillating model. The spatial distribution of the impact pressure was studied. Studies revealed that the tissue collision during phonation produces a very large impact pressure which correlates with the lung pressure and glottal width. Larger lung pressure and a narrower glottal width increase the impact pressure. The impact pressure was found to be roughly the square root of lung pressure. In the inferior-superior direction, the maximum impact pressure is related to the narrowest glottis. In the anterior-posteriorfirection, the greatest impact pressure appears at the midpoint of the vocal fold. The match between our numerical simulations and clinical observations suggests that this self-oscillating finite-element model might be valuable for predicting mechanical trauma of the vocal folds.
Show PACS
43.70.Aj Anatomy and physiology of the vocal tract, speech aerodynamics, auditory kinetics
43.70.Bk Models and theories of speech production
43.70.Jt Instrumentation and methodology for speech production research

Broadband sound generation by confined pulsating jets in a mechanical model of the human larynx

Zhaoyan Zhang and Luc G. Mongeau

J. Acoust. Soc. Am. Volume 119, Issue 6, pp. 3995-4005 (2006); (11 pages) | Cited 3 times

Full Text: Read Online (HTML) | Download PDF

Show Abstract
Experiments were performed to study the production of broadband sound in confined pulsating jets through orifices with a time-varying area. The goal was to better understand broadband sound generation at the human glottis during voicing. The broadband component was extracted from measured sound signals by the elimination of the periodic component through ensemble averaging. Comparisons were made between the probability density functions of the broadband sound in pulsating jets and of comparable stationary jets. The results indicate that the quasi-steady approximation may be valid for the broadband component when the turbulence is well established and the turbulence kinetic energy is comparatively large. A wavelet analysis of the broadband sound showed that random sound production was modulated at the driving frequency. Two distinct sound production peaks were observed during one cycle, presumably associated firstly with jet formation and secondly with flow deceleration during orifice closing. Most high-frequency sound was produced during the closing phase. Deviations from quasi-steady behavior were observed. As the driving frequency increased, sound production during the opening phase was reduced, possibly due to the shorter time available for turbulence to develop. These results may be useful for better quality voice synthesis.
Show PACS
43.70.Bk Models and theories of speech production
43.28.Ra Generation of sound by fluid flow, aerodynamic sound and turbulence
43.70.Aj Anatomy and physiology of the vocal tract, speech aerodynamics, auditory kinetics
43.28.Py Interaction of fluid motion and sound, Doppler effect, and sound in flow ducts

Evidence for attractors in English intonation

Bettina Braun, Greg Kochanski, Esther Grabe, and Burton S. Rosner

J. Acoust. Soc. Am. Volume 119, Issue 6, pp. 4006-4015 (2006); (10 pages) | Cited 8 times

Full Text: Read Online (HTML) | Download PDF

Show Abstract
Although the pitch of the human voice is continuously variable, some linguists contend that intonation in speech is restricted to a small, limited set of patterns. This claim is tested by asking subjects to mimic a block of 100 randomly generated intonation contours and then to imitate themselves in several successive sessions. The produced f0 contours gradually converge towards a limited set of distinct, previously recognized basic English intonation patterns. These patterns are “attractors” in the space of possible intonation English contours. The convergence does not occur immediately. Seven of the ten participants show continued convergence toward their attractors after the first iteration. Subjects retain and use information beyond phonological contrasts, suggesting that intonational phonology is not a complete description of their mental representation of intonation.
Show PACS
43.70.Fq Acoustical correlates of phonetic segments and suprasegmental properties: stress, timing, and intonation
43.71.Bp Perception of voice and talker characteristics
43.66.Ba Models and theories of auditory processes
43.66.Fe Discrimination: intensity and frequency
Return to All Sections
Close

Home Publications Meetings Contact ASA Site Map Back to Top

Copyright © Acoustical Society of America

close