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Noise-to-Harmonics Ratio as an Acoustic Measure of Voice Disorders in Boys   总被引:2,自引:0,他引:2  
This prospective study assessed the efficacy of computerized noise-to-harmonics ratio (NHR) to quantify perceptual and endoscopic findings of dysphonia and/or structural lesion of the vocal fold. Fifty Brazilian boys without vocal complaints were submitted to computerized, perceptual, and endoscopic examination. Thirty boys were dysphonic--3 were classified into the grade category, 5 into breathiness, 9 into roughness, and 15 into grade/breathiness. Vocal fold lesions were observed in 25 boys (17 nodules and 8 cysts). The Mann-Whitney U test revealed that NHR was significantly higher in boys with a structural lesion (p = 0.007) and in boys with dysphonia (p < 0.0001). However, according to a logistic regression model, only the occurrence of dysphonia was explained by NHR; the risk for having dysphonia increased approximately twice (odds ratio = 1.92, 95% confidence interval = 1.3-2.9) with each increase of 0.01 in NHR. Our results suggest that noise is a useful quantitative index to confirm a perceptual diagnosis of dysphonia and to evaluate quantitative changes in a dysphonic voice over time. However, we believe that computerized analysis should be used as a complement, rather than a substitute, for perceptual evaluation. Further studies with a larger sample are required to investigate the relationship between noise and lesions of the vocal folds.  相似文献
2.
Voice profiles were taken of 277 healthy children between the ages of 5 and 14 years. The measured phonetograms were grouped according to sex and years of age. In each group, the means and standard deviations of maximal and minimal volume of each frequency were calculated. The median was used to establish the upper and lower limits of the voice range of each group. No age-dependent changes of the group voice profiles were shown in the groups of 7 to 10 year olds. Out of that emerged a standard childhood voice profile of the untrained voice. After age 10, an increase of the dynamic range over the lowest frequencies was found. Because of the voice changes in puberty, a profile for 13- and 14-year-old boys could not be established.  相似文献
3.
Phonation threshold pressure has been defined as the minimum subglottalpressure to generate phonation. Previous research has indicated that children may habitually employ higher subglottal pressures than adults. In the present investigation sound pressure level (SPL) and subglottal pressures at different pitch levels were measured at and above phonation threshold in nine children. Phonation threshold values were scattered in reasonable agreement with Titzes' prediction, although a discrepancy was noted regarding the frequency dependence in some voices. At normal conversational loudness and loudest level of phonation the children's PS values were between two to four and four to eight times the predicted threshold values, respectively. At normal conversational loudness and habitual pitch subglottal pressures were lower than those previously observed for children, but similar to those found for female adults. The SPL in softest and loudest phonation were somewhat lower as compared to previous phonetogram data for children and for female adults. At normal loudness and habitual pitch the SPL values were similar to those of female adults. For a doubling of Ps mean SPL increased by 10.5 dB on the average.  相似文献
4.
Fundamental frequency (F0) perturbation has been found to be useful as an acoustic correlate of the perception of dysphonia in adult voices. In a previous investigation, we showed that hoarseness in children's voices is a stable concept composed mainly of three predictors: hyperfunction, breathiness, and roughness. In the present investigation, the relation between F0 perturbation and hoarseness as well as its predictors was analyzed in running speech of six children representing different degrees of hoarseness. Two perturbation measures were used: the standard deviation of the distribution of perturbation data and the mean of the absolute value of perturbation. The results revealed no clear relation.  相似文献
5.
Vocal parenting is a pedagogical approach that views the teachingof singing to children as a nurturing process. It encompasses the development of fundamentally sound vocal technique, guidance in repertoire selection and performance practices, and concern for the physical, mental, and emotional well-being of the child as a singer, performer, and person. Role-play and storytelling are among the strategies employed to fully integrate vocal technique with the personality of the singer.  相似文献
6.
The third formant (F3) of /a/ recorded from 209 healthy children (104 male and 105 female; ages 3 to 12 years) and 40 adults (20 men and 20 women) was studied by spectral analysis. Contrary to the traditional concept, the results of this study showed that there is significant difference in voice F3 of /a/ between male and female children. This difference was found to begin to develop at the age of 3 years and became substantial by the age of 6 years. In this study, the value of F3 obtained from female children at the age of 6 years was unexpectedly higher than that from the male children at the same age, which indicates that there is a difference in timbre in small children of both sexes.  相似文献
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