• KSII Transactions on Internet and Information Systems (TIIS)
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• v.6 no.11
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• pp.2800-2812
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• 2012

The purpose of this study was to examine the syllable-word boundary misalignment cost on word segmentation in Korean continuous speech. Previous studies have demonstrated the important role of syllabification in speech segmentation. The current study investigated whether the resyllabification process affects word recognition in Korean continuous speech. In Experiment I, under the misalignment condition, participants were presented with stimuli in which a word-final consonant became the onset of the next syllable. (e.g., /k/ in belsak ingan becomes the onset of the first syllable of ingan 'human'). In the alignment condition, they heard stimuli in which a word-final vowel was also the final segment of the syllable (e.g., /eo/ in heulmeo ingan is the end of both the syllable and word). The results showed that word recognition was faster and more accurate in the alignment condition. Experiment II aimed to confirm that the results of Experiment I were attributable to the resyllabification process, by comparing only the target words from each condition. The results of Experiment II supported the findings of Experiment I. Therefore, based on the current study, we confirmed that Korean, a syllable-timed language, has a misalignment cost of resyllabification.

• Phonetics and Speech Sciences
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• v.14 no.4
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• pp.11-17
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• 2022

This study investigates closure durations of Korean stops in terms of laryngeal contrasts, places of articulation, and three positions within words. Twenty-two Korean speakers produced the nonsense words containing Korean stops found in word-initial and word-final positions and between vowels. The statistical results showed that the closure durations differed significantly by laryngeal contrast and place of articulation. In addition, the differences by position within words were marginally significant. The closure durations were in the order of lenis < aspirated < fortis stops by laryngeal contrast, velar < alveolar < bilabial stops by place of articulation, and word-final < word-initial < between vowels by positions within words. The laryngeal contrasts were neutralized in word-final position as per coda neutralization in Korean phonology. This study shows that closure durations should be considered a valuable phonetic cue to identify stops on par with voice onset time and f0.

• Speech Sciences
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• v.14 no.1
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• pp.105-119
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• 2007

The purpose of this study is to examine Korean students' production and perception of word-final stop voicing in light of their overseas experience. Subjects were English native speakers, Korean university students with residence experience in America, Korean university students without residence experience in America, and Korean elementary school students. They participated in both production and perception tests. Results showed that the students' production and perception with residence experience in America appeared quite similar to those of the English native speakers. In the production tests, we noticed somewhat different results in temporal and frequency features. The one-year residence in America had some influence on their frequency features, but not the temporal features in the word final stop production. That difference could be seen in the perception tests, too. We could not find any difference in the identification test of the final release environment between the Korean university students who had studied abroad and those who didn't. Rather the difference could be found in the cue influence test in both the final release and non-release environments.

• Phonetics and Speech Sciences
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• v.3 no.3
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• pp.69-75
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• 2011

This paper investigates phrase positional effects on the timing of F0 (pitch) peaks in Tokyo Japanese disyllabic words with varying accent type (HL or LH) and phrase position (final or non final). The F0 peak timing was normalized by the total word duration ('normalized H timing'). The normalized H timing was significantly affected by accent type and phrase position. The H timing was later in the LH accent type than in the HL accent type, and in non final positions than in final positions. In addition, to examine the validity of the quantitative results, different models of phrase position effects were compared by measuring H timing in two approaches: normalization versus relative distance measures. For the normalization measures, the H timing was measured as the time of the F0 peak divided by the total word duration or by the duration of the tone bearing syllable. For the relative distance measures, the H timing was measured as the distance in milliseconds from the end of the word or from the end of the associated syllable. The best model was the normalization by the total word duration, rather than by the duration of the tone bearing syllable. This means that phrase positional effects on the timing of F0 peaks in Japanese disyllabic words are best modeled in terms of proportion of the total word duration.

• Journal of The Korean Society of Integrative Medicine
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• v.8 no.4
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• pp.291-305
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• 2020

Purpose : The duration of speech segments reflects children's speech motor development. The purpose of this study was to determine whether segmental sound and word duration varies by age among preschool children. Methods : A total of 60 children aged 4~5 years participated in this study. Participants took the picture-naming test to produce single-word speech data. The duration of the consonant at the initial position of the word and the final position of the word, the voice onset time of plosive, the duration of the vowel following the initial consonant, and the duration of the word were measured. Results : As age increased, the duration of the initial consonant, the duration of the word, and the voice onset time decreased significantly. The main effects of age, manner of articulation, and place of articulation on the duration of the initial consonant were significant. The duration of consonants in the nasal sound and plosives and the duration of bilabial and alveolar sound differed significantly between groups. The main effects of age and vocal type on voice onset time were significant. The main effect of age on the duration of the consonant in the final position of word and on the duration of the vowel were not statistically significant. Conclusion : The results of this study showed that the duration of segmental sound and the word were associated with speech development between 4 and 5 years old. Accordingly, duration of the segmental sound and the word may serve as an acoustic cue as they reflect speech development and speech motor control maturity.

• Speech Sciences
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• v.7 no.4
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• pp.169-186
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• 2000

This paper aims to confirm the mispronunciation of native Korean students due to the phonetic and phonological system differences between English and Korean, and to find the works-to-do by experiment. Many Korean students tend to differentiate the sounds of word-final stop consonants not by vowel duration or the allophones but by the phoneme of the consonant itself. In English, Stop sounds change through the conditions of the aspirated, unaspirated, or unreleased sounds. But in Korean they are not allophones of phonemes but distinct phonemes. Therefore, many Korean students are apt to add an extra vowel sound /i/ after the final stop consonant in the eve form due to both the unperception of the differences between the phonemes and the allophones of stop consonants, and the influence of the Korean sound-sequence relationship. Since the replacement of the allophones and extra vowel addition does not change the meaning, the importance was almost lost. Nevertheless, this kind of study is essential for the precise learning and the use of the English language.

• The Journal of the Acoustical Society of Korea
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• v.13 no.5
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• pp.24-31
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• 1994

In this paper, we study continuous speech recognition of Korean language using acoustic models of word juncture coarticulation. To alleviate the performance degradation due to coarticulation problems, we use context-dependent units that model inter-word transitions in addition to intra-word transitions. In all cases the initial phone of each word has to be specified for each possible final phone of the previous word similarly for the final phone of each word. To improve the robustness of the HMM parameters, the covariance matrix is smoothed. We also use position-dependent units to improve the discriminative power between units. Simulation results show that when the improved models of word juncture coarticulation are used. the recognition performance is considerably improved compared to the baseline system using only intra-word units.

• Phonetics and Speech Sciences
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• v.7 no.3
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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.

• Phonetics and Speech Sciences
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• v.7 no.3
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• pp.73-78
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• 2015

This study explores the degree of velarization of English word-final /l/ (i.e., /l/-darkness) according to the lexical status. Lexical status is defined as whether a speech stimulus is considered as a word or a non-word. We examined the temporal and spectral properties of word-final /l/ in terms of the duration and the frequency difference of F2-F1 values by varying the immediate pre-liquid vowels. The result showed that both temporal and spectral properties were contrastive across all vowel contexts in the way of real words having shorter [l] duration and low F2-F1 values, compared to non-words. That is, /l/ is more heavily velarized in words than in non-words, which suggests that lexical status whether language users encode the speech signal as a word or not is deeply involved in their speech production.

• Speech Sciences
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• v.14 no.1
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• pp.37-62
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• 2007

The current study examines the role of post-lexical tonal patterns of a prosodic phrase in word segmentation. In a word spotting experiment, native Korean listeners were asked to spot a disyllabic or trisyllabic word from twelve syllable speech stream that was composed of three Accentual Phrases (AP). Words occurred with various post-lexical intonation patterns. The results showed that listeners spotted more words in phrase-initial than in phrase-medial position, suggesting that the AP-final H tone from the preceding AP helped listeners to segment the phrase-initial word in the target AP. Results also showed that listeners' error rates were significantly lower when words occurred with initial rising tonal pattern, which is the most frequent intonational pattern imposed upon multisyllabic words in Korean, than with non-rising patterns. This result was observed both in AP-initial and in AP-medial positions, regardless of the frequency and legality of overall AP tonal patterns. Tonal cues other than initial rising tone did not positively influence the error rate. These results not only indicate that rising tone in AP-initial and AP_final position is a reliable cue for word boundary detection for Korean listeners, but further suggest that phrasal intonation contours serve as a possible word boundary cue in languages without lexical prominence.