• Korean Journal of Cleft Lip And Palate
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• v.12 no.1
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• pp.1-6
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• 2009

Oronasal fistula are a well-known complication of surgical treatment of cleft palate, occurring most frequently in the alveolus and hard palate. Previous reports have demonstrated that oronasal fistulas, particularly if greater than l cm in diameter, had an adverse effect on speech. The aim of this study was to demonstrate the relationship between the size of the fistula and the influence on velopharyngeal function. The site and size of the fistula were indicated on graph paper with calipers and measured in $mm^2$. Speech assessment was carried out using a Nasometer, VPI articulation differential test, spectrography. Patient whose fistulas affected their speech had significantly larger fistulas than those whose fistulas did not. The study shows that the larger the fistula, the greater the risk of hypernasality and nasal emission, but even small fistulas can cause speech problems. If obstruction of the nasal passage is eliminated in a patient with a previously asymptomatic fistula, it may result in a fistula becoming symptomatic, resulting in hypernasality and nasal emission. In conclusion, even small fistulas can influence speech production and should be considered before any treatment is planned. The study lends support to early closure of oronasal fistulas, particularly before pharyngeal flap surgery is contemplated.

• Phonetics and Speech Sciences
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• v.6 no.2
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• pp.73-79
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• 2014

Alveolar fricative sounds /s/ and /s'/ are learned last for normal children in the speech development process for Koreans. These are especially difficult to articulate for hearing-impaired children often causing articulation errors. The acoustic phonetic evaluation uses testing tools to provide indirect and object information. These objective resources can be compared with standardized resources on speech when interpreting the results of a test. However, most previous studies in Korea did not consider acoustic studies that used the spectrum moment values of hearing-impaired children. Therefore, this study was conducted to compare the characteristics of hearing-impaired children's pronunciation of fricative sounds using spectrum moment values. For this purpose, the study selected a total of 10 hearing-impaired children (5 boys and 5 girls) currently in 3rd or 5th grade and attending one of the elementary schools in Seoul or Gyeonggi-do. For the selection process, their age, type of hearing aid, implantation of hearing aid (CI) before two years of age, hearing capacity (dB) before and after wearing the hearing aid, duration of speech rehabilitation, and time of learning alveolar fricative sounds were all considered. Also, 10 normal children (5 boys and 5 girls) were selected among 3rd or 5th grade students attending one of the elementary schools in Seoul or Gyeonggi-do. The subjects were asked to read the carrier sentence, "I say _______," including a list of 12 meaningless syllables composed of CV and VCV syllables, including alveolar fricative sounds /s/ and /s'/ and vowels /a/, /i/, and /u/. The recorded resources were processed through the Time-frequency Analysis Software Program to measure M1 (mean), M2 (variance), M3 (skewness), and M4 (kurtosis) of the fricative noise. No significant differences were found when comparing spectrum threshold values in the acoustic phonetic characteristics of hearing-impaired children and normal children in alveolar fricative sound pronunciation according to vowels /a/, /i/, and /u/, alveolar fricative sounds /s/ and /s'/, and syllable structure (CV, VCV) other than, for M3 in the comparison of groups according to disability. In the comparison of syllable structures, there were statistically significant differences in M1, M2, M3, and M4 with clinical significance. However, there was no significant difference in results when comparing the alveolar fricative sounds according to the vowels.

• Phonetics and Speech Sciences
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• v.12 no.3
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• pp.1-14
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• 2020

Previous studies have confirmed that /o/ and /u/ in Seoul Korean are undergoing a merger in the F1/F2 space, especially for female speakers. As a substitute parameter for formants, it is reported that female speakers use phonation (H1-H2) differences to distinguish /o/ from /u/. This study aimed to explore whether H1-H2 values are being used as perceptual cues for /o/-/u/. A perception test was conducted with 35 college students using /o/ and /u/ spoken by 41 females, which overlap considerably in the vowel space. An acoustic analysis of 182 stimuli was also conducted to see if there is any correspondence between production and perception. The identification rate was 89% on average, 86% for /o/, and 91% for /u/. The results confirmed that when /o/ and /u/ cannot be distinguished in the F1/F2 space because they are too close, H1-H2 differences contribute significantly to the separation of the two vowels. However, in perception, this was not the case. H1-H2 values were not significantly involved in the identification process, and the formants (especially F2) were still dominant cues. The study also showed that even though H1-H2 differences are apparent in females' production, males do not use H1-H2 in their production, and both females and males do not use H1-H2 in their perception. It is presumed that H1-H2 has not yet been developed as a perceptual cue for /o/ and /u/.

• Phonetics and Speech Sciences
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• v.12 no.3
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• pp.25-32
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• 2020

An analysis of emotional English utterances with 7 emotions (calm, happy, sad, angry, fearful, disgust, surprised) was conducted using the measurement of prosodic distance between 672 emotional and 48 neutral utterances. Applying the technique proposed in the automatic evaluation model of English pronunciation to the present study on emotional utterances, Euclidean distance measurement of 3 prosodic elements such as F0, intensity and duration extracted from emotional and neutral utterances was utilized. This paper, furthermore, extended the analytical methods to include Euclidean distance normalization, z-score and z-score normalization resulting in 4 groups of measurement schemes (sqrF0, sqrINT, sqrDUR; norsqrF0, norsqrINT, norsqrDUR; sqrzF0, sqrzINT, sqrzDUR; norsqrzF0, norsqrzINT, norsqrzDUR). All of the results from perceptual analysis and acoustical analysis of emotional utteances consistently indicated the greater effectiveness of norsqrF0, norsqrINT and norsqrDUR, among 4 groups of measurement schemes, which normalized the Euclidean measurement. The greatest acoustical change of prosodic information influenced by emotion was shown in the values of F0 followed by duration and intensity in descending order according to the effect size based on the estimation of distance between emotional utterances and neutral counterparts. Tukey Post Hoc test revealed 4 homogeneous subsets (calm

• Phonetics and Speech Sciences
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• v.12 no.3
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• pp.73-83
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• 2020

Measured values may differ between Multi-Dimensional Voice Program (MDVP), Praat, and Time-Frequency Analysis software (TF32), all of which are widely used in voice quality analysis, due to differences in the algorithms used in each analyzer. Therefore, this study aimed to compare the values of parameters of normal voice measured with each analyzer. After tokens of the vowel sound /a/ were collected from 35 normal adult subjects (19 male and 16 female), they were analyzed with MDVP, Praat, and TF32. The mean values obtained from Praat for jitter variables (J local, J abs, J rap, and J ppq), shimmer variables (S local, S dB, and S apq), and noise-to-harmonics ratio (NHR) were significantly lower than those from MDVP in both males and females (p<.01). The mean values of J local, J abs, and S local were significantly lower in the order MDVP, Praat, and TF32 in both genders. In conclusion, the measured values differed across voice analyzers due to the differences in the algorithms each analyzer uses. Therefore, it is important for clinicians to analyze pathologic voice after understanding the normal criteria used by each analyzer when they use a voice analyzer in clinical practice.

• Phonetics and Speech Sciences
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• v.12 no.3
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• pp.41-53
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• 2020

A wh-phrase in an embedded sentence may have either an embedded or a matrix scope. Interpretation of a wh-phrase with a matrix scope has tended to be syntactically unacceptable unless the sentence reads with a wh-intonation. Previous studies have found two differences in prosodic characteristics between sentences with matrix and embedded scopes. Firstly, peak F0s in wh-phrases produced with an F0 compression wh-intonation are higher than those in indirect questions, and peak F0s in matrix verbs are lower than those in sentences with embedded scope. Secondly, a substantial F0 drop is found at the end of embedded sentences in indirect questions, whereas no F0 reduction at the same point is noticed in sentences with a matrix scope produced with a high plateau wh-intonation. However, these characteristics were not found in our experiment. This showed that a more compelling difference exists in the values obtained from subtraction between the peak F0s of each word (or a word plus an ending or case marker) and the F0s at the end of the word. Specifically, the gap between the peak F0 in a word composed with an embedded verb and the F0 at the end of the word, which is a complementizer in Korean, is large in embedded wh-scope sentences and low in matrix wh-scope sentences.

• Phonetics and Speech Sciences
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• v.12 no.3
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• pp.85-94
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• 2020

Vowel articulation in subjects related to speech disorders seems to be difficult. A chant method that properly reflects the characteristics of language could be used as an effective way of addressing the difficulties. The purpose of this study was to find out whether the chant method is effective as a means of enhancing vowel articulation. The subjects of this study were 60 normal adults (30 males and 30 females) in their 20s and 30s whose native language is Korean. Eight utterance conditions including chanting and reading conditions were recorded and their acoustic data were analyzed. The results of the analysis of the acoustic variables related to the formant confirmed that the F1 and F2 values of the vowel formants are increased and the direction of movement of the center of gravity of the vowel triangle is statistically significantly forwarded and lowered in the chant method in both the word and the phrase context. The results also proved that accent is the most influential musical factor in chant. There was no significant difference between four repeated tokens, which increased the reliability of the results. In other words, chanting is an effective way to shift the center of gravity of the vowel triangle, which suggests that it can help to improve speech intelligibility by forming a desirable place for articulation.

• Phonetics and Speech Sciences
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• v.12 no.3
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• pp.95-103
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• 2020

The current study aimed to identify the characteristics of speech rate and pause in children with spastic cerebral palsy (CP) and their relationships with speech intelligibility. In all, 26 children with CP, 4 with no speech motor involvement and age-appropriate language ability (NSMI-LCT), 6 with no speech motor involvement and impaired language ability (NSMI-LCI), 6 with speech motor involvement and age-appropriate language ability (SMI- LCT), and 10 with speech motor involvement and impaired language ability (SMI-LCI) participated in the study. Speech samples for the speech rate and pause analysis were extracted using a sentence repetition task. Acoustic analysis were made in Praat. First, it was found that regardless of the presence of language impairment, significant group differences between the NSMI and SMI groups were found in speech rate and articulation rate. Second, the SMI groups showed a higher ratio of pause time to sentence production time, more frequent pauses, and longer durations of pauses than the NSMI groups. Lastly, there were significant correlations among speech rate, articulation rate, and intelligibility. These findings suggest that slow speech rate is the main feature in SMI groups, and that both speech rate and articulation rate play important roles in the intelligibility of children with spastic CP.

• Phonetics and Speech Sciences
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• v.12 no.3
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• pp.65-71
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• 2020

Feature normalization is a method to reduce the effect of environmental mismatch between the training and test conditions through the normalization of statistical characteristics of acoustic feature parameters. It demonstrates excellent performance improvement in the traditional Gaussian mixture model-hidden Markov model (GMM-HMM)-based speech recognition system. However, in a deep neural network (DNN)-based speech recognition system, minimizing the effects of environmental mismatch does not necessarily lead to the best performance improvement. In this paper, we attribute the cause of this phenomenon to information loss due to excessive feature normalization. We investigate whether there is a feature normalization method that maximizes the speech recognition performance by properly reducing the impact of environmental mismatch, while preserving useful information for training acoustic models. To this end, we introduce the mean and exponentiated variance normalization (MEVN), which is a compromise between the mean normalization (MN) and the mean and variance normalization (MVN), and compare the performance of DNN-based speech recognition system in noisy and reverberant environments according to the degree of variance normalization. Experimental results reveal that a slight performance improvement is obtained with the MEVN over the MN and the MVN, depending on the degree of variance normalization.

• Phonetics and Speech Sciences
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• v.2 no.4
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• pp.245-252
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• 2010

Korea does not have a certain criteria on the respiratory ability and phonation of the normal aged, and also has no clear standard to examine the boundaries of geriatric diseases. This study analyzed the characteristics in respiration and phonation of the aged in normal healthy elderly from diverse angles with different variables. Thirty-three participants in total, seven males and eight females in the age group 55-64 participated in the study. Seven males and eleven females in the age group 65-74 were selected for the respiration and phonation experiments, and 10 different variables such as FVC, $FEV_1$, $FEV_1$/FVC, MPT, MFR, Psub, f0, jitter, shimmer and NHR were comparatively analyzed for each group of different age and gender. To see the difference in respiration and phonation by age and gender, the study conducted a two-way ANOVA. First, from the result of the analysis on respiratory ability, FVC of male appeared to be significantly greater than female. In both age groups of 55-64 and 65-74, male displayed greater FVC than female did. Second, as for $FEV_1$, $FEV_1$/FVC, the age group of 55-64 showed greater values than the values measured in the age group of 65-74. Third, MFR showed a significant difference by gender. In both age groups, male showed significantly higher MFR than female. Fourth, for different gender, a significant difference in MFR was observed. In both age groups of 55-64 and 65-74, male exhibited higher MFR than female. This study has a clinical implication in that it analyzed the criteria on respiration and phonation in normal healthy elderly according to gender and age. The normal aged showed a difference in their respiratory and phonatory functions by age and gender, it was closely related to the decline of pulmonary function due to the physical aging and the weak respiration coming from weakness of respiratory muscles. Also, the physical differences in height, weight, and the muscles in laryngeal and respiratory system between males and females had an influence on the performance. These results from this study might be a helpful guideline for the clinical criterion in the future.