• Speech Sciences
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• v.12 no.3
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• pp.153-164
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• 2005

Two identical experiments are conducted at a six month interval in order to examine the VOT and its effect on the whole syllable duration or the rest portion of the syllable in Busan Korean. Just like the general characteristics of VOT, the aspirated stops consistently exhibit the longest VOT while tense stops have the shortest VOT. However, alveolar stops exhibit shorter VOT than labial stops, and it is contrary to the previous studies which claim that VOT values of labial stops are shorter than VOT values of alveolar stops. Moreover, there is a relationship between VOT and syllable/VC duration across stops. While VOT and syllable/VC duration have symmetric relationship for the aspirated velar and bilabial stops, other lax and tense stops exhibit the inverse relationship between the VOT and syllable/VC duration.

• Proceedings of the KSPS conference
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• 2000.07a
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• pp.199-199
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• 2000

Korean stops are 3 system: aspirated, fortis, lenis, whereas English stops are 2 system: voiced, voiceless. Because in Korean, lenis stop is realized by slight aspirated voiceless stop, it is likely to produce English word initial voiced stop as voiceless stop. We divide subjects into three group-native, experienced, unexperienced- and investigate differences between group. VOT of experienced group IS same as native group, but VOT of unexperienced group is longer than native group. VOt of unexperienced group is 1.8 times than native group. We survey whether the height of following vowel influences VOT of initial stop. As a result, for all group, VOT followed by low vowel is shorter than VOT followed by high vowel. But this tendency is more salient in unexperienced group. For high vowel, VOT of unexperienced group is 2.05 times than native group, whereas for low vowel, it is just 1.55 times. The unexperienced pronounce well English word initial voiced stop followed by low vowel than high vowel. Samples are divided into two group according to type of coda consonant- nasal and voiceless stop. But average of VOT is similar and there is no significant difference between two groups. There is no influence by type of coda consonant. The average of phrases is compared to the average of isolated words. In the case of natives and experienced, there is no significant differences between phrases and words, but in the case of unexperienced, VOT of phrases becomes shorter than words. But VOT of unexperienced is still longer than native group.

• Phonetics and Speech Sciences
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• v.4 no.3
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• pp.51-58
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• 2012

The purpose of this study is to measure the impact of Korean speakers' English stop pronunciation on their general pronunciation proficiency. For these purposes, 20 Korean speakers read English sentences and their pronunciations were rated by native English speakers. The Korean speakers' VOT values of English stops in sentences were then measured and the relation between the VOT values and native speakers' pronunciation rating was compared. Here, the relation between (1) the proficiency score of each speaker and VOT values; and (2) the proficiency score of each sentence and VOT values were analyzed. The results show that there is a relation between the proficiency score of each sentence and VOT values of /t, b, d, g/; and there is a relation between VOT values of /t, b, d, g/ and proficiency scores of each speaker while these is a weak relation between VOT values of /p, k/ and proficiency scores of each speaker.

• Journal of the Korean Society of Laryngology, Phoniatrics and Logopedics
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• v.8 no.1
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• pp.49-53
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• 1997

Aberrations in VOT measures in apraxia of speech are indicative of speech motor programming impairment. In English, overlaps of VOT between voiceless and voiced plosives have been frequently observed in patients with apraxia of speech. Unlike English, Korean plosives constitute trichotomy in terms of manner of production, that is, voiceless aspirated /p', t', k'/ ; voiceless or voiced, weakly aspirated /p-b, t-k, k-g/ ; or voiceless, heavily aspirated /p, t, k/. In this spectrographic study, VOT measures during Korean plosives produced by a patient with apraxia of speech were compared to those by age- and gender- matching normal subjects. The results indicated that there were partial overlaps between VOT of /b, d, g/ and those of /p, t, k/, implying that the errors were phonetic in nature. In addition, larger VOT variabilities in apraxia of speech compared to the normals were noted.

• Phonetics and Speech Sciences
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• v.9 no.3
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• pp.41-47
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• 2017

The purpose of this study is to examine how speakers use VOT and f0 to distinguish tense, lax, and aspirated stops in isolated sentence reading and paragraph readings. To do so, a total of 20 males between the ages of 20-25 years old were asked to read (1) isolated sentences, (2) information-oriented text and (3) emotional expressive texts in which the stop pronunciation's VOT value and f0 were measured thereafter. The main results are as follows. In the isolate sentence reading, lax stops, and aspirated stops were distinguished by both VOT and f0, but for the Korean men that read reading texts, VOT is not a cue to distinguish between lax and aspirated stops. In general, the VOT differences between lax stops and aspirated stops were smaller for information-oriented texts and emotional expressive texts than that of the isolate sentence reading. In the paragraph reading that induces a natural utterance, the f0 dependence is greater for the distinction between lax and aspirated stops.

• Phonetics and Speech Sciences
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• v.13 no.2
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• pp.9-17
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• 2021

Voice onset time (VOT) is known to be a primary acoustic cue that differentiates voiced from voiceless stops in the world's languages. While much attention has been given to the sound change of Korean stops, little attention has been given to that of English stops. This study examines VOT of stop consonants as produced by English speakers in comparison to Korean speakers to see whether there is any VOT change for English stops and how the effects of stop, place, gender, and individual on VOT differ cross-linguistically. A total of 24 native speakers (11 Americans and 13 Koreans) participated in this experiment. The results showed that, for Korean, the VOT merger of lax and aspirated stops was replicated, and, for English, voiced stops became initially devoiced and voiceless stops became heavily aspirated. English voiceless stops became longer in VOT than Korean counterparts. The results suggest that, similar to Korean stops, English stops may also undergo a sound change. Since it is the first study to be revealed, more convincing evidence is necessary.

• Phonetics and Speech Sciences
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• v.13 no.3
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• pp.53-64
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• 2021

It is known that the voicing contrast for Japanese word-initial stops is primarily realized as differences in the voice onset time (VOT). However, recent studies have reported that voiced stops are more often produced with a positive VOT than with a negative VOT among the younger generation nationwide. It is also known that post-stop F0 is associated with the stop contrast, but the degree of F0 use differs from region to region. This study explores whether the difference in post-stop F0 functions as a perceptual cue to the stop contrast along with VOT. Fifty-five college students who are native listeners from four different regions participated in two or three perception tests. The results show that VOT is a primary cue to the voiced-voiceless distinction of word-initial stops, but that the effect of post-stop F0 on the stop contrast is marginal. The post-stop F0 is involved in perception only when VOT is ambiguous, such that a sound with high F0 is more often perceived as a voiceless stop, but not vice versa. The results of this study indicate that the acoustic parameters associated with the stop contrast are not the same in production and perception, and suggest that other factors such as context, which is not an acoustic characteristic, may also be involved in the stop contrast.

• The Journal of the Korea Contents Association
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• v.14 no.3
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• pp.482-489
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• 2014

The purposes of this study are (1) to see if the length of residence in Korea affects to the VOT values of Korean plosives produced by Chinese speakers (2) to investigate if such VOT values are different in non-sense words and real words and (3) to find out how such VOT values are related to the native Korean speakers' understanding of the words. For these purposes, eighteen Chinese speakers' VOT values of Korean plosives were measured using Speech Analyzer and their pronunciations were evaluated by three native Korean speakers. The results show that there is no effect of both (1) length of residence in Korea and (2) production of non-sensed words and sensed words. In addition, it is noticed that VOT values of some plosives affect more to the native Korean speakers' understanding of the words, while some are not.

• Phonetics and Speech Sciences
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• v.12 no.4
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• pp.1-8
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• 2020

Traditionally it has been understood that the aspirated and lenis stops in Seoul Korean are distinguished primarily by voice onset time (VOT) and secondarily by other cues such as the fundamental frequency (F0) of the following vowel. However, recent studies on stop production have shown that the aspirated and lenis stops are currently merging in VOT and that they are now differentiated primarily by F0. In the present study, we examined whether the currently reported change in the production domain would be also found in the perception domain. To this end, an auditory identification task was conducted using speech materials of varying VOT and F0 values with young and older male and female Seoul listeners. Results revealed that all listener groups used both VOT and F0 to distinguish the lenis vs. aspirated stops but they used the F0 cue more reliably than the VOT cue in discriminating the stop contrast. The effects of gender and age were found only in the VOT cue (i.e., not in the F0 cue), with the greatest VOT cue weight in older males and the smallest in young females, which is in line with recent production studies.

• Proceedings of the KSPS conference
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• 2003.10a
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• pp.163-167
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• 2003

The present thesis examines the correlation of VOT and F0 in the three-way distinction of Korean obstruents, conducting production and perception tests. In the production test, one female native speaker of Korean with a Seoul dialect (the author) recorded 15 repetitions of a monosyllabic word list including /ka, kha, k*a, pa, pha, p*a, ta, tha, t*a, ca, cha, c*a/ in random order, VOT and F0 of the following vowels were measured, and the result was significant for the three-way distinction with a strong correlation between VOT and F0, and also in the VOT-F0 plot, no overlapping among the domains was observed. As for the perception test, I manipulated the data recorded in the production test, heightening or lowering their F0 values. In all, 14 subjects (seven males and seven females) participated in the identification test. The result was as follows: the fortis stimuli were not influenced by F0 changes, and the VOT and F0 values at the lenis-aspirated boundary were negatively correlated. From these results I concluded the following: 1) VOT and F0 can distinguish the three domains of Korean obstruents without overlapping; 2) the fortis perception does not need F0 as its acoustic cue; and 3) VOT and F0 in the distinction between the lenis and aspirated are in the phonetic trading relation[2].