• 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.

• 대한음성학회지:말소리
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• 제21_24호
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• pp.144-175
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• 1992

This paper aims to discuss determining factors of Korean allophones and to formulate and classify Korean allophonic rules systematically. The relationship between allophones and coarticulation, the most. influential factor of allophonic variation, is thoroughly investigated. Other factors -- speech tempo and style, dialect, and social factors such as age, set, class etc. -- are also briefly discussed. Allophonic rules are classified into two groups -- 3) those relevant to coarticulation and 2) those irrelevant to coarticulation. Rules of the first group are further classified into four subgroups according to the directionality of the coarticulation. Each allophonic nile formulation is explained and discussed in detai1. The allophonic rules formulated and classified in this paper are 1) Devoicing of Voiced Consonants, 2) Devoicing of Vowels, 3) Nasal Approach and Lateral Approach, 4) Uvularization, 5) Palatalization, 6) Voicing of Voiceless Lax Consonants, 7) Frication, 8) Labialization, 9) Nasalization, 10) Release Withholding and Release Masking, 11) Glottalization, 12) Flap Rule, 13) Vowel Weakening, and 14) Allophones of /ㅚ, ㅟ, ㅢ/ (which are realized as diphthongs or as monophthongs depending on phonetic contexts).

• 음성과학
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• 제10권1호
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• pp.59-67
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• 2003

The purpose of this study was to investigate Korean native speakers' perception of English sounds according to groupings of phonetic contrasts. The four groupings looked at were vowels, voicing (voiced-unvoiced), fricatives with difference in place of articulation, and other clusters of specific sound contrasts, such as stop-fricatives and liquids. The position of a sound in syllable was also examined. According to the results of ANOVA and a post-hoc analysis, the perception of vowels, in the medial position was different from that of consonants in the initial and final position. Vowels proved to be the most difficult group to perceive correctly. With the consonants, there was not a big difference whether the contrasts came initially or finally. The order of difficulty was liquids, fricatives, stop-fricatives, and finally voicing.

• 말소리와 음성과학
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• 제4권3호
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• pp.31-41
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• 2012

Recent studies have shown that the stop system of Korean is undergoing a sound change in terms of the two acoustic parameters, voice onset time (VOT) and fundamental frequency (f0). Because of a VOT merger of a consonantal opposition and onset-f0 interaction, the relative importance of the two parameters has been changing in Korean where f0 is a primary cue and VOT is a secondary cue in distinguishing lax from aspirated stops in speech production as well as perception. In English, however, VOT is a primary cue and f0 is a secondary cue in contrasting voiced and voiceless stops. This study examines how Korean English learners use the two acoustic parameters of L1 in producing L2 English stops and whether the sound change of acoustic parameters in L1 affects L2 speech production. The data were collected from six adult Korean English learners. Results show that Korean English learners use not only VOT but also f0 to contrast L2 voiced and voiceless stops. However, unlike VOT variations among speakers, the magnitude effect of onset consonants on f0 in L2 English was steady and robust, indicating that f0 also plays an important role in contrasting the [voice] contrast in L2 English. The results suggest that the important role of f0 in contrasting lax and aspirated stops in L1 Korean is transferred to the contrast of voiced and voiceless stops in L2 English. The results imply that, for Korean English learners, f0 rather than VOT will play an important perceptual cue in contrasting voiced and voiceless stops in L2 English.

• 디지털융복합연구
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• 제10권5호
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• pp.233-238
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• 2012

유성음원과 무성음원을 시용하는 음성부호화 방식에 있어서, 같은 프레임 안에 모음과 무성자음이 있는 경우에 음성 파형에 일그러짐이 나타난다. 이것을 해결하기 위하여 본 논문에서는 개별피치와 LMS(Least Mean Square)를 적용한 LMS-MPC를 제시하였으며, 기존의 MPC와 LMS-MPC의 SNRseg를 평가한 결과, LMS-MPC의 남자음성에서 1.5dB, 여자음성에서 1.3dB 개선된 것을 확인할 수 있었다. 결국, MPC에 비해 LMS-MPC의 SNRseg가 개선되어 음성파형의 일그러짐을 제어할 수 있었으며, 본 방법은 셀룰러폰이나 스마트폰과 같이 Low Bit Rate의 음원을 사용하여 음성신호를 부호화 하는 방식에 활용할 수 있을 것으로 기대된다.

• 음성과학
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• 제9권1호
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• pp.137-148
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• 2002

This study investigates phonation modes of vowels following the affricate consonants in Korean and English- -tense affricate /c'/, lenis affricate /c/, and aspirated affricate /$c^{h}$/ for Korean; voiced affricate /$\check{J}$/ and aspirated affricate /c/ for English. The investigation makes significant use of the H1*-H2* measure (a normalized amplitude difference between the first and second harmonics) to provide acoustic correlates of the phonation types. The major findings for English are that the H1*-H2* measure at the vowel onset was significantly larger in post-aspirated position than in post-voiced position. The Korean data showed the H1*-H2* measure at the vowel onset to be significantly higher in the post-aspirated class than in the post-tense class. On the other hand, the Fo values for the post-lenis vowels were significantly lower than those of the other two classes during the first half of the vowel. Based on the phonetic results, this study argues for the need to incorporate the [stiff vocal folds] and [slack vocal folds] features into the phonological treatments of Korean affricates, while maintaining the two features [constricted glottis] and [spread glottis].

• 말소리와 음성과학
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• 제6권2호
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• pp.141-151
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• 2014

This study reports anti-hierarchical initial-syllable lengthening of an utterance-internal phrase in Korean. That is, the phrase-initial syllable (e.g., /a/ of "apa-do" or /ma/ of "mapa-do") starting with a voiced phoneme (i.e., vowels or voiced consonants) manifests itself as significantly longer when it is preceded by another phrase without a pause than when it leads an utterance or follows a pause utterance-internally. The phenomenon was examined with regard to two other factors: (1) tempo and (2) tenseness of the consonant (/p, $p^{\prime}$, $p^h$/) following the target syllable /a/. First, the effect of tempo on initial lengthening was not significant. Apart from the statistical significance, however, a tendency was observed, i.e., the slower the tempo is, the greater the lengthening. By contrast, the faster the tempo is, the higher the ratio (%) of lengthening. Second, contrary to our expectations, initial-syllable lengthening was even greater before tense stops /$p^{\prime}$, $p^h$/ than before lax stop /p/ regardless of tempo, and it was remarkable when it comes to the ratio (%), which means that initial lengthening is free of the pre-consonantal vowel shortening effect. Final-syllable lengthening is a pre-boundary marker, while the initial-syllable lengthening is regarded as a post-boundary marker of a phrase.

• 음성과학
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• 제12권4호
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• pp.113-128
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• 2005

The underlying premise of this study was that L1 production is easily transferred into L2 production. In neutral intonation, there is a consonant-tone correlation in Korean: High tone patterns are correlated with voiceless aspirated and tense consonants and Low-High tone patterns are correlated with lax or other voiced consonants. The purpose of this study was to see whether the correlation in Korean (L1) is transferred into English (L2) production and whether the degree of transfer differs depending on the degree of proficiency. Eight Korean speakers and two American speakers participated in the experiment. F0 contours of words and sentences were collected and analyzed. The results of the present study showed that there is a strong correlation between voicing and tone in L2 utterances. When utterance-initial consonant types were voiceless, the word or the sentence began with the H pattern; otherwise it had the LH pattern. The degree of interference differed depending on the degree of proficiency: less proficient speakers showed a stronger correlation in terms of the magnitude (Hz) and size (ms) of the effects on F0. The results indicate that the consonant-tone correlation in L1 is strongly transferred into L2 production and the correlation transfer can be one of the actual aspects that cause L2 speakers to produce deviant L2 accents and intonation.

• 음성과학
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• 제7권1호
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• pp.203-216
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• 2000

The purpose of this study is to revisit the property of the Korean plain stops in intervocalic position. More specifically, focusing on a word-internal, intervocalic position, this study investigates 1) how often speakers pronounce intervocalic. stops as fully voiced, 2) in what amount each speaker voice the plain stops during the stop closure, 3) whether the preceding or the following vowel influences the voicing of target consonants, and 4) the fundamental frequency pattern at the vowel onset after the target consonant shows any consistent pattern, regardless of whether voicing is present during the closure. The results of this study give strong support for the phonetic account of the voicing distinction in Korean. (Jun 1995, 1996).

• 말소리와 음성과학
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• 제7권1호
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• pp.89-95
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• 2015

We explored Dutch listeners' perception of Korean three-way contrast of fortis, lenis, and aspirated stops. The three Korean stops are all voiceless word-initially, whereas Dutch distinguishes between voiced and voiceless stops, so Korean voiceless stops were expected to be difficult for the Dutch listeners. Among the three Korean stops, fortis stops are phonetically most similar to Dutch voiceless stops, thus they were expected to be the easiest to distinguish for the Dutch listeners. Dutch and Korean listeners carried out a discrimination task using three crucial comparisons, i.e., fortis-lenis, fortis-aspirated, and lenis-aspirated stops. Results showed that discrimination between lenis and aspirated stops was the most difficult among the three comparisons for both Dutch and Korean listeners. As expected, Dutch listeners discriminated fortis from the other stops relatively accurately. It seems likely that Dutch listeners relied heavily on VOT but less on F0 when discriminating between the three Korean stops.