• The Journal of the Acoustical Society of Korea
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• 제24권1E호
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• pp.28-33
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• 2005

This study was designed to suggest an assessment tool for analyzing the characteristics of Korean phonetic contrast intelligibility among dysarthric individuals. The intelligibility deficit factors of phonetic contrast in Korean dysarthric patients were analyzed through stepwise regression analysis. The 19 acoustic-phonetic contrasts proposed by Kent et al. (1999) have been claimed to be useful for clinical assessment and research on dysarthria. However, the test cannot be directly applied to Korean patients due to linguistic differences between English and Korean. Thus, it is necessary to devise a Korean word intelligibility test that reflects the distinct characteristics of the Korean language. To identify the speech error characteristics of a Korean dysarthric group, a Korean word list was audio-recorded by 3 spastic, 4 flaccid, and 5 mixed type of dysarthric patients. The word list consisted of monosyllabic consonant-vowel-consonant (CVC) real word pairs. Stimulus words included 41 phonemic contrast pairs and six triplets. The results showed that the percentage of errors in final position contrast was higher than in any other position. Unlike the results of previous studies, the initial-position contrasts were crucial in predicting the overall intelligibility among Korean patients.

• 한국음향학회지
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• 제31권5호
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• pp.298-308
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• 2012

This study was designed to examine the phoneme recognition errors of hearing-impaired (HI) listeners on a consonant-by-consonant basis, to show (1) how each HI ear perceives individual consonants differently and (2) how standard clinical measurements (i.e., using a tone and word) fail to predict these differences. Sixteen English consonant-vowel (CV) syllables of six signal-to-noise ratios in speech-weighted noise were presented at the most comfortable level for ears with mild-to-moderate sensorineural hearing loss. The findings were as follows: (1) individual HI listeners with a symmetrical pure-tone threshold showed different consonant-loss profiles (CLPs) (i.e., over a set of the 16 English consonants, the likelihood of misperceiving each consonant) in right and left ears. (2) A similar result was found across subjects. Paired ears of different HI individuals with identical pure-tone threshold presented different CLPs in one ear to the other. (3) Paired HI ears having the same averaged consonant score demonstrated completely different CLPs. We conclude that the standard clinical measurements are limited in their ability to predict the extent to which speech perception is degraded in HI ears, and thus they are a necessary, but not a sufficient measurement for HI speech perception. This suggests that the CV measurement would be a useful clinical tool.

• 말소리와 음성과학
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• 제6권4호
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• pp.3-15
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• 2014

An articulatory study (using an Electromagnetic Articulography, EMA) was conducted to explore effects of prosodic boundary strength (Intonational Phrase/IP versus Word/Wd), and focus (Focused/accented, Neutral, Unfocused/unaccented) on the kinematic realization of /m/ in the coda (${\ldots}$am#i${\ldots}$) and the onset (${\ldots}$a#mi${\ldots}$) conditions in Korean. (Here # refers to a prosodic boundary such as an IP or a Wd boundary). Several important points have emerged. First, the boundary effect on /m/s was most robustly observed in the temporal dimension in both the coda (IP-final) and the onset (IP-initial) conditions, generally in line with cross-linguistically observable boundary-related lengthening patterns. Crucially, however, in contrast with boundary-related slowing-down effects that have been observed in English, both the IP-final and IP-initial temporal expansions of Korean /m/s were not accompanied by an articulatory slowing down. They were, if anything, associated with a faster movement in the lip opening (release) phase (into the vowel). This suggests that the mechanisms underlying boundary-related temporal expansions may differ between languages. Second, observed boundary-induced strengthening effects (both spatial and temporal expansions, especially on the IP-initial /m/s) were remarkably similar to prominence (focus)-induced strengthening effects, which is again counter to phrase-initial strengthening patterns observed in English in which boundary effects are dissociated from prominent effects. This suggests that initial syllables in Korean may be a common focus for both boundary and prominence marking. These results, taken together, imply that the boundary-induced strengthening in Korean is different in nature from that in English, each being modulated by the individual language's prosodic system. Third, the coda and the onset /m/s were found to be produced in a subtly but significantly different way even in a Wd boundary condition, a potentially neutralizing (resyllabification) context. This suggests that although the coda may be phonologically 'resyllabified' into the following syllable in a phrase-medial position, its underlying syllable affiliation is kinematically distinguished from the onset.

• 한국음향학회:학술대회논문집
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• 한국음향학회 2000년도 하계학술발표대회 논문집 제19권 1호
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• pp.321-324
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• 2000

한국어는 어두에서 유성파열음이 나타나지 않고 약한 기식이 있는 연자음으로 실현되므로 영어의 유성파열음을 발음하기 어렵다. 한국인이 어두 유성파열음을 습득할 때 후속하는 모음의 높이가 영향을 미치리라 가정하고 /이, 에, 어, 우/ 4개의 모음을 선택하여 어두유성파열음 의 VOT에 영향을 미치는가를 단독단어와 문장에서 살펴보았다. native, 숙련자, 미숙련자의 세 그룹으로 나누어 실시한 결과 native의 경우 후속하는 모음이 어두파열음의 VOT에 영향을 끼치지 않았으며, 이러한 경향은 숙련자 그룹에서도 지켜짐을 알 수 있었다. 그러나 미숙련자 그룹인 경우 고모음이 저모음에서보다 VOT가 현저하게 길었고 통계검사 결과 유의미한 차이를 보여, 고모음에서 유성발음을 잘 못함을 알 수 있었다. native와 숙련자 그룹은 intermediate phrase(이하 iP) initial인 단어나 iP medial인 문장에서 VOT가 거의 유사한데 비해 미숙련자 그룹에서는 문장 내에서 VOT가 조금씩 짧아졌고 이 경향은 고모음에서 두드러져 통계적으로 유의미한 차이를 보였다.

• 한국음향학회:학술대회논문집
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• 한국음향학회 2000년도 하계학술발표대회 논문집 제19권 1호
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• pp.99-102
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• 2000

In the case of making large vocabulary speech recognition system, it is better to use the segment than the syllable or the word as the recognition unit. In this paper, we study on the basis of making biphone for Korean speech recognition. For experiments, we use the speech toolkit of OGI in U.S.A. The result shows that the recognition rate of the case in which the diphthong is established as a single unit is superior to that of the case in which the diphthong Is established as two units, i.e. a glide plus a vowel. And also, the recognition rate of the case in which the biphone is used as the recognition unit is better than that of the case in which the mono-phoneme is used.

• 음성과학
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• 제11권3호
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• pp.23-36
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• 2004

Many languages show reverse durational variation between preceding vowel and following voiced/voiceless (lax/tense) consonants. This study investigated the likely effects of phoneme type (tense vs. lax) on the timing structure (duration of syllable, word, phrase and sentence) of Korean. Three rates of speech (fast, normal, slow) applied to stimuli with the target word /a-Ca/ where /C/ is one of /p, p', $p^h$/. The type (tense/lax) of /C/ caused marked inverse durational variations in the two syllables /a/ and /Ca/ and highly different durational ratios between them. Words with /p', $p^h$/ were significantly longer than that with /p/, which contrasts with many other languages where such pairs of words have a similar duration. The differentials between words remained up to the phrase and sentence level, but in general the higher linguistic units did not statistically differ within each level. Thus, the phrase is suggested as a compensatory unit of phoneme type effects in Korean. Different rates did not affect the general tendency. Distribution of time variations (from normal to fast and slow) to each syllable (/a/ and /Ca/) was also observed.

• 말소리와 음성과학
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• 제5권1호
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• pp.73-80
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• 2013

Formant is one of the essential vocal features for research of voice production, recognition and synthesis. Numerous studies were established on foreign languages including English vowels. However, studies related to Korean were done with a limited number of voice data. In this study, we compare four formants according to age and gender using a large number of Korean monophthongs. A total of 2614 Korean speakers participated in our experiments. We summarize statistical results by mean and standard deviation for each formant of five monophthongs. The results show a notable difference in each age and gender group. A quantitative study based on a large dataset is suggested for future studies on Korean speech sounds.

• 대한음성학회지:말소리
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• 제65호
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• pp.13-36
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• 2008

This paper attempts to analyze the characteristics of Korean vowel production by 12 Korean native speakers and 36 adult learners. The analyses have been performed with investigations of F1and F2 values. Results showed that there's no significant difference between /ㅔ/ and /H/ and between /ㅗ/ and /ㅜ/ in Korean native speakers' pronunciations. The distinguishing tendencies found in the analyses of foreign learners' pronunciations are fronting and lowering of /ㅗ/ by English speakers, backing and heightening of /ㅓ/ by Japanese speakers and backing and lowering of /ㅏ/ by Chinese speakers. For the limitations of this paper, it has a meaning of a preliminary study and could be developed into further research to show the order of acquisition and L1 transference.

• 음성과학
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• 제14권4호
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• pp.41-52
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• 2007

Recent experimental studies have shown that language-users' knowledge of the statistical characteristic of their native language plays a key role in their task performance. One specific instance of this that the current study focuses on is the effect of phonotactic probabilities on speakers' wordlikeness judgment of nonwords. In this paper, I explore the question of whether the judgment of Korean speaking subjects as to the wordlikeness of Korean nonsense words is influenced by the degree of association between two-phoneme sequences in Korean. The current results suggest that the objective measure of correlations (expressed by $r_{\phi}$ values) between an onset consonant and a vowel inside Korean syllables play an important role in Korean speakers' nonword processing. The current results additionally indicate an effect of the correlations of two-phoneme sequences including vowels and coda consonants on nonword processing. Implications of these findings for Korean speakers' learning the correlations between adjacent segments inside the syllable are discussed.

• 대한음성학회:학술대회논문집
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• 대한음성학회 2005년도 춘계 학술대회 발표논문집
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• pp.25-28
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• 2005

The purpose of this paper is to represent values of acoustic cues for Korean oral stops in the multi-dimensional space, and to attempt to find possible relationships among acoustic cues through correlation coefficient analyses. The acoustic cues used for differentiation of 3 types of Korean stops are closure duration, voice onset time and fundamental frequency of a vowel after a stop. The values of these cues are plotted in the two and three dimensional space and see what the critical cues are for complete separation of different types of stops. Correlation coefficient analyses show that there are statistically significant relationships among acoustic cues but they are not strong enough to make a conjecture that there is a possible articulatory relationship among the mechanisms employed by the acoustic cues.