• Journal of Audiology & Otology
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• v.25 no.3
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• pp.124-130
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• 2021

Background and Objectives: The study investigated vowel context effects on the perception of stop consonants in Malayalam. It also probed into the role of vowel context effects in determining the frequency of occurrence of various consonant-vowel (CV) syllables in Malayalam. Subjects and Methods: The study used a cross-sectional pre-experimental post-test only research design on 30 individuals with normal hearing, who were native speakers of Malayalam. The stimuli included three stop consonants, each spoken in three different vowel contexts. The resultant nine syllables were presented in original form and five gating conditions. The consonant recognition in different vowel contexts of the participants was assessed. The frequency of occurrence of the nine target syllables in the spoken corpus of Malayalam was also systematically derived. Results: The consonant recognition score was better in the /u/ vowel context compared with /i/ and /a/ contexts. The frequency of occurrence of the target syllables derived from the spoken corpus of Malayalam showed that the three stop consonants occurred more frequently with the vowel /a/ compared with /u/ and /i/. Conclusions: The findings show a definite vowel context effect on the perception of the Malayalam stop consonants. This context effect observed is different from that in other languages. Stop consonants are perceived better in the context of /u/ compared with the /a/ and /i/ contexts. Furthermore, the vowel context effects do not appear to determine the frequency of occurrence of different CV syllables in Malayalam.

• Korean Journal of Audiology
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• v.25 no.3
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• pp.124-130
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• 2021

Background and Objectives: The study investigated vowel context effects on the perception of stop consonants in Malayalam. It also probed into the role of vowel context effects in determining the frequency of occurrence of various consonant-vowel (CV) syllables in Malayalam. Subjects and Methods: The study used a cross-sectional pre-experimental post-test only research design on 30 individuals with normal hearing, who were native speakers of Malayalam. The stimuli included three stop consonants, each spoken in three different vowel contexts. The resultant nine syllables were presented in original form and five gating conditions. The consonant recognition in different vowel contexts of the participants was assessed. The frequency of occurrence of the nine target syllables in the spoken corpus of Malayalam was also systematically derived. Results: The consonant recognition score was better in the /u/ vowel context compared with /i/ and /a/ contexts. The frequency of occurrence of the target syllables derived from the spoken corpus of Malayalam showed that the three stop consonants occurred more frequently with the vowel /a/ compared with /u/ and /i/. Conclusions: The findings show a definite vowel context effect on the perception of the Malayalam stop consonants. This context effect observed is different from that in other languages. Stop consonants are perceived better in the context of /u/ compared with the /a/ and /i/ contexts. Furthermore, the vowel context effects do not appear to determine the frequency of occurrence of different CV syllables in Malayalam.

• Phonetics and Speech Sciences
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• v.8 no.3
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• pp.111-116
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• 2016

The Nasometer is most commonly used to assess the presence and degree of resonance problems in clinical settings and it provides nasalance scores to identify the acoustic correlates of nasality. Nasalance scores are influenced by factors related to speakers and speech stimuli. This study aims to examine the effect of vowel context and length of stimuli and age on nasalance scores. The participants were 20 adults and 45 children ranging in age from 3 to 5 years. The stimuli consisted of 12 sentences containing no nasal consonants. The stimuli in the three vowel contexts (low, high, and mixed) consisted of 4, 8, 16, and 31-syllable long sentences. Speakers were asked to repeat each stimulus after examiner. The results indicated significant effects of vowel contexts and stimulus length on nasalance scores. The nasalance scores for the high vowel contexts were significantly higher than those for the mixed and low vowel contexts. The nasalance scores for the mixed vowel contexts were significantly higher than those for the low vowel contexts. Speakers had higher nasalance scores for 4-syllable long sentences and 31-syllable long sentences than for 16-syllable long sentences. The effect of age on nasalance scores was not significant. The results of the study suggest that the vowel context and length of speech stimuli should be carefully considered when interpreting the nasalance scores.

• Speech Sciences
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• v.14 no.4
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• pp.81-98
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• 2007

This study aims to investigate whether shortened vowel duration conditioned by a following voiceless stop induces phonetic reduction of vowel space in English, and whether the reduction appears more in the height dimension than in the backness dimension (Lindblom, 1963; Flemming, 2005). Fifteen native speakers of American English read minimal pairs containing ten American English vowels in [bVd] and [bVt] syllables in a carrier phrase. All the subjects produced shorter vowels in the voiceless than in the voiced context. However, a reduction in vowel space and a raising of low vowels due to the shortened vowel duration were generally not found. To the contrary, the speakers tended to exhibit even more lowering of low vowels in the voiceless context, and vowel space was more commonly compressed in the backness dimension than in the height dimension. Many speakers, in particular, demonstrated fronting of the high back vowel [u] in the voiceless context. It was interpreted that due to a relatively large number of English vowels in the narrower low vowel space, the raising of low vowels may give rise to confusion in vowel contrasts, and therefore the degree of phonetic vowel reduction is restricted in that region. On the other hand, the high vowel region, being relatively spacious in English, allows a certain degree of phonetic vowel reduction in the F2 dimension. It is possible that heavy requirements for maintaining vowel contrasts may cause speakers to overachieve vowel target values, especially when faced with vowels which are difficult to distinguish due to shortened vowel duration, leading to an over-lowering of the low vowels.

• Phonetics and Speech Sciences
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• v.12 no.2
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• pp.17-27
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• 2020

This paper examines kinematic characteristics of /pk/ clusters, as compared to /kk/ and /pp/ with varying vowel contexts and speech rate. The results of EMMA data from eight Seoul-Korean speakers indicate as follows. Firstly, comparing /pk/ to /pp/ sequences, lips closing movement was faster and spatially greater in the /a/-to-/a/ context while temporally longer in the /i/-to-/i/ context. It was smaller in spatial displacement and shorter in temporal duration in /pk/ sequences. Peak velocity did not vary. Secondly, comparing /pk/ with /pp/ and /kk/ controls, lip aperture was less constricted in the /a/-to-/a/ context than /i/-to-/i/, but the maximum contact between the upper and lower lips was invariant across different vocalic contexts within /pk/ sequences (/apka/=/ipki/). Categorical reduction of C1 in /pk/ sequences fell in with the low-vowel and fast-rate conditions with across-/within-speaker variability. Gradient reduction of C1 was observed in all C1C2 types, being more frequent in fast rate. Lastly, the jaw articulator was a stable indicator of rate effects. The implication of the current study is that gestural reduction occurs with categorical reduction and general spatiotemporal weakening in the assimilating contexts, while quantitative properties of gestures may be a reason for gradient reduction, not necessarily confined to place assimilation.

• Phonetics and Speech Sciences
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• v.1 no.2
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• pp.95-103
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• 2009

We investigated the perceptual structure of Korean consonants by analyzing the confusion among consonants in various vowel contexts. The 36 CV syllable types combined by 18 consonants and 2 vowels (/i/ and /u/) were presented with masking noises or in degraded intensity. The confusion data were analyzed by the INDSCAL (Individual Difference Scaling), ADCLUS (Additive Clustering) and the probability of the transmitted information. The results were compared with those of a previous study with /a/ vowel context (Bae and Kim, 2002). The overall results showed that the laryngeal features-aspiration, lax and tense-are the most salient features in the perception of Korean consonant regardless of vowel contexts, but the perceptual saliency of place features varies across vowel conditions. In high vowel (front and back vowel) contexts, sibilant consonants were perceptually salient compared to in low vowel contexts. In back vowel contexts, grave (labial and velar) consonants were perceptually salient. These findings imply that place features and vowel features strongly interact in speech perception as well as in speech production. All statistical measures from our confusion data ensured that the perceptual structure of Korean consonants correspond to the hierarchical structure suggested in the feature geometry (Clements, 1991). We discuss the link between speech perception and production as the basis of phonology.

• Phonetics and Speech Sciences
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• v.6 no.4
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• pp.17-26
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• 2014

The present study examined epenthetic vowels produced by Korean learners of English in read sentences, in terms of acoustic measures and extra-phonological factors. The results demonstrated three main findings. First, epenthetic vowels had relatively high F1 values and a wide range of F2 values. Most of the epenthetic vowels were inserted near Korean high central vowels, but some vowels were inserted near front vowels due to co-articulation with surrounding vowels. Second, vowel epenthesis was affected by the context. The results showed that the epenthesis was frequently seen with word junctions between obstruents (e.g., stops-fricatives). Third, Korean learners were not affected by English background and were very weakly affected by orthography. English experience, which is one of the extra-phonological factors, was not related to epenthesis production. However, orthography, the other extra-phonological factor, very weakly affected the amount of epenthesis production. Nine percent of all epenthesis production was affected by the English past-tense suffix '-ed'; approximately 70% of the participants were affected by this suffix. The findings of the present study contributed to understanding vowel epenthesis. First, the study revealed that the epenthetic vowels produced by Korean learners of English were close to the high central vowel, supporting previous studies that the epenthetic vowel is quite close to the shortest vowel. Second, the study examined the various phonetic environments of epenthetic vowels, revealing that vowel epenthesis occurred more frequently in a certain phonetic circumstance.

• Phonetics and Speech Sciences
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• v.1 no.4
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• pp.39-46
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• 2009

This study compares the perception of English high tense and lax vowels (/i, I, u, $\mho$/) by English speakers and Korean speakers of English. The four vowels were produced in /hVd/ context by a native speaker of English, and each word's vowel duration was manipulated to range from 170ms to 290ms in 30ms increments. Two English speakers and six Korean speakers of English were asked to listen to pairs of tense and lax vowel words with manipulated vowel durations and to identify the pair by choosing either heed-hid or hid-heed for front vowels and either who'd-hood or hood-who'd for back vowels. The results show that English speakers distinguished tense vowels from lax vowels with 100% accuracy regardless of the different durations, compared to 62% accuracy for Korean speakers of English. Most errors occurred for lengthened lax vowels and shortened tense vowels. The results of this study demonstrate that Korean speakers mainly rely on vowel duration as a cue to discriminate the tense and lax vowels. The theoretical and pedagogical implications of this finding are discussed.

• Phonetics and Speech Sciences
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• v.4 no.4
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• pp.3-17
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• 2012

This study examines Korean speakers' production of English consonant clusters, focusing on vowel insertion. An acoustic analysis along with a statistical test was carried out to see what factors are involved in this production. The following factors were considered in the present study: phonetic properties, L1 transfer, and cluster types. Specifically, liquid types were considered to see if they cause any difference depending on C+/l/ or C+/r/ clusters in the onset in terms of vowel insertion patterns. That is, it was examined which Korean speakers produce better, C+/l/ or C+/r/ clusters. Interestingly, the result of the present experiment shows that the correct answer percent was higher in the C+/r/ onset clusters than C+/l/ onset clusters unlike Eckman's (1977) Marked Differential Hypothesis. In other words, the occurrence of the vowel insertion in C+/l/ clusters is higher than C+/r/ onset clusters. This may be attributed to L1 transfer. Furthermore, in the present study, three patterns of vowel insertion in the C+/l/ clusters were identified by implementing an acoustic analysis based on vowel duration and formant: a) vowel insertion with gemination, b) phonological epenthesis, and c) phonetic intrusion. However, phonetic intrusion mainly occurred in the C+/r/ clusters. Data were collected from 54 Korean speakers to see what factors are involved in vowel insertion patterns in the production of English consonant clusters. This study provides evidence for L1 transfer, the duration effect of /l/ in a different context, and three kinds of vowel insertion patterns in conjunction with gestural coordination by age groups.

• Proceedings of the Acoustical Society of Korea Conference
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• 1998.08a
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• pp.177-183
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• 1998

보통 말씨와 clear speech에서, 영어 전설모음[ i, , , e ]를 일정한 강세를 갖도록 하고, 모음의 길이를 변화시켜 음향적 분석을 하였다. 그 결과, 모음의 음가가 주변의 자음과 비슷한 값으로 변화하였으며, 그 변화 정도는 모음의 길이와 직접적인 관련이 있었으며, 이러한 변화의 크기는 clear speech에서 더 적었다. 이러한 결과는 clear speech 가 단순히 보통 말씨보다 소리가 큰 것일 뿐 아니라, 체계적으로 모음축약 현상을 보상하기 위하여 음향적인 특성을 재구성하는 것임을 시사한다.