• 말소리와 음성과학
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• 제7권3호
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• pp.117-128
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• 2015

This paper investigates the acoustic-perceptual relation between Korean dent-alveolar fricatives and the English voiceless alveolar fricative /s/ in varied prosodic contexts (e.g., stress, accent, and word initial position). The denti-alveolar fricatives in Korean show a two-way distinction, which can be referred to as either plain (lenis) /s/ or fortis /$s^*$/. The English alveolar voiceless fricative /s/ that corresponds to the two Korean fricatives would be placed in a one-to-two non-native phoneme mapping situation when Korean listeners hear English /s/. This raises an interesting question of how the single fricative of English perceptually maps into the two-way distinction in Korean. This paper reports the acoustic-perceptual mapping pattern by investigating spectral properties of the English stimuli that are heard as either /s/ or /$s^*$/ by Korean listeners, in order to answer the two questions: first, how prosody influences fricatives acoustically, and second, how the resultant properties drive non-native listeners to interpret them as segmental features instead of as prosodic information. The results indicate that Korean listeners' responses change depending on the prosodic context in which the stimuli are placed. It implies that Korean speakers interpret some of the information provided by prosody as segmental one, and that the listeners take advantage of the information in their judgment of non-native phonemes.

• 말소리와 음성과학
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• 제2권3호
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• pp.37-46
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• 2010

This study investigates acoustic characteristics of English and Korean voiceless sibilant fricatives as they appear before the three vowels, /i/, /$\alpha$/ and /u/. Three measurements - duration, center of gravity and major spectral peak - are employed to compare acoustic properties and vowel effect for each fricative sound. This study also investigates the question of whether Korean sibilant fricatives are acoustically similar to the English voiceless alveolar fricative /s/ or to the palato-alveolar /$\int$/. The results show that in the duration of frication noise, English /$\int$/ is the longest and Korean lax /s/ the shortest of the four sounds. It is also observed that English alveolar /s/ has the highest value, whereas Korean /s/ shows the lowest value in the frequency of center of gravity. In terms of major spectral peak, while English /s/ reveals the highest frequency, English /$\int$/ shows the lowest value. In addition, evidence indicates that there is a strong vowel effect in the fricative sounds of both languages, although the vowel effect patterns of the two languages are inconsistent. For instance, in the major spectral peak, both Korean lax /s/ and tense /$s^*$/ show significantly higher frequencies before the vowel /$\alpha$/ than before the other vowels, whereas both English /s/ and /$\int$/ exhibit significantly higher frequencies before the vowel /i/ than before the other vowels. These results indicate that Korean sibilant fricatives are acoustically distinct from both English /s/ and /$\int$/.

• 말소리와 음성과학
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• 제10권3호
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• pp.41-48
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• 2018

This study examined the acoustic characteristics of Korean alveolar fricatives of normal children. Developing children aged 3 and 7, typically produced 2 types of nonsense syllables containing alveolar fricative /sV/ and /VsV/ sequences where V was any one of three corner vowels (/i, a, and u/). Stimuli containing the speech materials used in a production experiment were presented randomly to 12 speech language pathologists (SLPs) for a perception test. The SLPs responded by selecting one of seven alternative sounds. Acoustic measures such as duration of frication noise, normalized intensity, skewness, and center of gravity were examined. There was significant difference in acoustic measures when comparing vowels. Comparison of syllable structures indicated statistically significant differences in duration of frication noise and normalized intensity. Acoustic parameters could account for the perceptual data. Relating the acoustic and perception data by means of logistic regression suggests that duration of frication noise and normalized intensity are the primary cues to perceiving Korean fricatives.

• 말소리와 음성과학
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• 제7권3호
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• pp.107-115
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• 2015

In this paper English word-final /s/ and /z/ produced by English and Korean speakers were investigated. The durations and maximum intensities of these fricatives with those of their preceding vowels were compared. In the English speakers' productions, they relied on the ratio of the durations of them as well as the ratio of the maximum intensities of them. In their productions, the /s/ was long in duration and high in maximum intensity and its preceding vowel was short in duration whereas the /z/ was short in duration and low in maximum intensity and its preceding vowel was long in duration. However, the maximum intensities of the preceding vowels were not different in their productions. But in the Korean speakers' productions, they relied on neither the ratio of the durations of them nor the ratio of the maximum intensities of them. In their productions, the /s/ and the /z/ were not different in durations, but the duration of the preceding vowel of the /s/ was shorter than that of /z/, and the maximum intensities of the /s/ and /z/ as well as their preceding vowels were not different. Based on these results we can conclude that in distinguishing /CVs/ and /CVz/ words, English speakers used durations and intensities of the word-final fricatives in addition to durations of the vowels whereas Koreans used only durations of the vowels.

• 말소리와 음성과학
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• 제16권1호
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• pp.33-40
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• 2024

본 연구는 치조 마찰음의 왜곡 오류인 치간음화, 구개음화, 설측음화가 적률분석의 변인인 무게중심, 분산, 왜도, 첨도에서 정조음과 보이는 음향학적 차이를 확인하고자 하였다. 이를 위해 61명 아동(평균연령: 5.6±1.5세, 여아 19명, 남아 42명)을 대상으로 얻어진 조음음운평가(Assessment of Phonology & Articulation for Children, APAC; Urimal-test of Articulation and Phonology I, U-TAP I) 결과, 음성 중 치조 마찰음을 포함하고 있는 목표 단어에서 치조마찰음 왜곡 오류를 보인 음성과 정조음 음성을 추출하여 후향적 연구를 진행하였다. 총 169개의 음성이 적률분석에 사용되었다. 그 결과, 무게중심에서 정조음이 구개음화보다 값이 높았으며, 구개음화는 치간음화보다 값이 낮았다. 치간음화의 분산이 정조음과 구개음화보다 높았다. 치간음화가 정조음보다 높은 왜도를 보였으며 구개음화의 왜도가 정조음보다 높았다. 마지막으로 구개음화의 첨도가 정조음과 치간음화보다 높았다. 각 왜곡 오류 유형에서 적률분석의 모든 변인들에 대해 조음위치(어두초성, 어중초성), 발성유형(평음, 경음)에 따른 유의한 차이는 관찰되지 않았다. 본 연구는 치조 마찰음의 유형에 따라 무게중심, 분산, 왜도, 첨도에서 다른 패턴이 나타남을 확인하였으며, 본 연구에서 제시한 객관적 수치는 추후 임상에서 청지각 평가를 도와 치조 마찰음 왜곡 오류의 진단과정에 기초 자료로 사용될 수 있을 것이다.

• 음성과학
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• 제3권
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• pp.93-108
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• 1998

This paper attempts to acoustically examine the place of articulation of Korean affricates. In order to pursue an acoustic analysis of where Korean affricates are articulated, we resort to LPC spectra of the Korean plain affricate /c/ in intervocalic position, based on theoretical assumptions (e.g., Stevens 1993a), and compare the data to that of the Korean alveolar consonants /t, s/ in the same context. Our phonetic results show that in intervocalic position, the Korean plain affricate is alveolar just like the Korean alveolar consonants /t, s/, supporting the articulatory studies of $Skali{\check{c}}kov{\acute{a}}$ (1960) and Kim (1997).

• 음성과학
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• 제9권3호
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• pp.169-184
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• 2002

Korean has two types of voiceless alveolar fricatives: a non-tense fricative /$S^{h}$ and a tense fricative /s'/. Twenty native speakers of Korean produced five pairs of isolated words containing word initial $S^{h}V$ and /s'V/ sequences where V was any one of five (/a, e, i, o, u/) of Korean vowels. Acoustic measures such as duration, fricative noise prominent frequency, energy change of following vowel, and fundamental frequency at vowel onset were examined. Results showed that among the parameters, aspiration noise duration of /s'/ in mid and low vowel contexts was less than 21 ms. In a perception experiment, where only the aspiration noise interval of the /$S^{h}$/ tokens was incrementally reduced, some listeners shifted perception from /$S^{h}$/ to /s'/.

• 대한후두음성언어의학회지
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• 제16권2호
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• pp.152-157
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• 2005

Background and Objectives : 10 normal Korean native speakers participated subjects to investigate the acoustic and aerodynamic study of Korean fricatives, affricates, and plosives and to make good use of the results for the patients with articulation problems. Materials and Method Their productions of [asa], [as'a], [aca], $[ac^ha]$, (ac'a), (ata) , $[at^ha]$, and [at'a] were analyzed with Lx Speech Studio Program (Laryngogrtaph Ltd, UK) for acoustic analysis and Phonatory Function Analyze. (Nagashima Ltd. Model PS 77H, Tokyo, Japan) for aerodynamic analysis. Results : The results are as follows : 1) Plosives showed higher Qx1 in vocal folds closure ratio than fricatives and affricates. 2) Tense fricatives, affricates, and plosives showed higher Qx2 in vocal folds closure ratio than asperated and 1ax. 3) Asperated showed higher Qx1 in vocal folds closure ratio than tense and 1ax. 4) Asperated showed higer peak flow rate than tense and 1ax. Conclusion This results may be helpful for treatment in articulation disorders.

• 대한후두음성언어의학회지
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• 제11권1호
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• pp.5-11
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• 2000

Background and Objectives : Tongue-tie, or partial ankyloglossia, is manifested by an abnormally short and thick lingual frenulum. Degree of tongue-tie varies from the mild to the rare, severe and its treatment of choice is frenulotomy. Theoretically tongue-tie can affect expression of alveolar sounds. The purpose of this study is to evaluate the degree of articulation problem and to evaluate the efficacy of frenulotomy itself on alveolar sounds in tongue-tie patients. Materials and Methods : Prospectively, the authors performed preoperative and postoperative speech evaluation using picture consonants test for tongue-tie patients. Percentage of consonants correct(PCC), mean value of each alveolar phoneme depends on articulation site were evaluated. for exclusion of other articulatory improving factors except of frenulotomy itself, postoperative picture consonants test was performed 1 month after surgery. Results : Preoperative speech evaluation was performed to 37(male 21, female 16) patients and postoperative speech evaluation was performed to 17(male 9, female 8) patients, the other 20 patients were follow-up loss. Low PCC was observed in tongue-tie patients and PCC of female was higher an at of male in 2-4 years old patients. Overall PCC was improved after frenulotomy. Preoperative mean value of liquids and fricatives was lower than the other alveolar phonemes(p＜0.05) and it was improved postoperatively(p＜0.05). Conclusion : Frenulotomy itself can improve the articulation of liquids and fricatives on short follow-up. Speech therapy would be needful for improvement of the other alveolar phonemes.

• 말소리와 음성과학
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• 제1권2호
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• pp.105-110
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• 2009

This paper introduces the technique of semi-automatically identifying different types of noise in the frequency domain. Given the lower cutoff frequency of the frication noise, and a user-specified constant, the technique identifies the boundary between the frication and aspiration noise in a Korean lax fricative followed by the vowel /a/ by comparing the upper and lower sums of energy with respect to the cutoff frequency. The user-specified constant can be adjusted for different speakers. When the technique was applied to distinguish the two types of noise of Korean lax fricatives from the same speaker, the average and standard deviation of the difference between the manually inserted boundaries and the automatically inserted boundaries were 2.67ms and 1.80ms respectively.