The effect of mouth opening levels on acoustic parameters of voice signal
Bibliographic record
Abstract
Objectives: This study examined the effect of three different mouth opening levels on fundamental frequency, jitter, shimmer, harmonic to noise ratio, first formant frequency, second formant frequency and first two formants ratio in Producing vowel /a/. Study design: simple random sampling strategy was used to recruit 36 participants. 18 females and 18 males between age 18 to 29 years were recruited. Methods: the participants sustained vowel /a/ 7 seconds. The first 1 second and the last 1 second of the vowel were omitted in order to eliminate the vowel initiation and termination effect from the audio signal and, thereby, the middle 5 seconds were analyzed to derive acoustic parameters. Seven infrared cameras recorded mouth opening and head movements. Results: The results showed that mouth opening level is only effective on fundamental frequency (p=0.009<0.05), shimmer (p=0.033<0.05) and first formant frequency (p=0.004<0.05). Conclusions: An open jaw posture places the larynx in a lower position which causes a more relaxed phonation that reduce fundamental frequencyand increase shimmer. Mouth opening level has an inverse relationship with first formant frequency.
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How this classification was reachedexpand
Full frame machine prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. The Gemma side is a direct model label for every work in the frame, read from the title-only record. The Codex side is a classifier learned from the 10,348 direct Codex labels and calibrated to design-weighted sample rates; fields without enough sample support carry no Codex call. Candidate is the union of the two sides; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels.
Distilled classifier scores by category (both heads)
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.001 | 0.006 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.000 | 0.000 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.002 | 0.000 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one source (direct Gemma or distilled Codex), not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".