• Phonetics and Speech Sciences
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• v.9 no.4
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• pp.51-57
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• 2017

The current study compared the acoustic features of the two phonation types for Korean fricatives (plain: /s/, fortis : /s'/) and the three types for affricates (aspirated : /$ts^h$/, lenis : /ts/, and fortis : /ts'/) in order to determine the phonetic status of the plain fricative /s/. Considering the different manners of articulation between fricatives and affricates, we examined four acoustic parameters (rise time, intensity, fundamental frequency, and Cepstral Peak Prominence (CPP) values) of the 20 Korean native speakers' productions. The results showed that unlike Korean affricates, F0 cannot distinguish two fricatives, and voice quality (CPP values) only distinguishes phonation types of Korean fricatives and affricates by grouping non-fortis sibilants together. Therefore, based on the similarity found in /$ts^h$/ and /ts/ and the idiosyncratic pattern found in /s/, this research concludes that non-fortis fricative /s/ cannot be categorized as belonging to either phonation type.

• Speech Sciences
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• v.6
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• pp.145-161
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• 1999

21 normal Korean native speakers participated as subjects to investigate the acoustic and aerodynamic study of Korean fricatives and affricates and to make good use of the results for the patients with articulation problems. Their productions of [sa], [s'a], [ca], [$c^{h}a$], [c'a], [asa], [as'a], [aca], [$ac^{h}a$], and [ac'a] were analyzed with CSL and AP II instruments. The results are as followings: (1) Fricatives showed higher frequency in minimum and maximum frequency and longer duration than affricates. (2) Fricatives showed higher peak flow rate and longer rise time than affricates. (3) When we compared the different phonemes with each other, their differences were usually statistically significant, but when we compared CV and VCV syllables, they did not show significant difference, even VCV's showed higher and longer values than CV syllables. (4) Normaly, lax fricatives and affricates showed lower frequency and higher peak flow rate, shorter frication duration, and longer rise time.

• Speech Sciences
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• v.11 no.2
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• pp.71-87
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• 2004

Korean has a pair of voiceless fricatives, whose laryngeal manifestation comes in parallel to stops and affricates with a three-way lexical contrast. Prior phonetic studies by Kagaya (1974), Iverson (1983), and Kang (1999, 2000) point out /s/ is associated with multiple characteristics of the larynx shared with not only the lax but also the aspirated series, whereas /s' / carries a laryngeal distinction typical of the tense consonants. The complex dual nature of /s/ is again supported by a psycholinguistic study by Kang (2004), as /s/ was found to interact with /$c^h$/ (17% of the time) as well as /c/ (57%) in speech errors. In addition, a recent work by Cho and Lee (2003) notes an interesting chain shift case in the acquisition of the fricatives. Although they observed a significant phonological pattern between child English and Korean, Cho and Lee's description of acquiring fricatives is far from being precise from the perspective of phonetics. From a longitudinal study of recorded tapes by two children at 1;7-3;8 and 1;7-2;1 respectively, I found that /s' / was usually substituted into tense noncontinuants in young children's early production as predicted, whereas /s/ having both lax and aspirated-like glottal properties revealed a complicated pattern of substitutions into lax, tense, and aspirated noncontinuants with a varying degree of preference relative to the subjects. The current acquisition study supports the previous claims concerning fricatives in other languages, showing that their acquisition comes after stops. Besides, it also notes that Korean fricatives are subject to a series of phonological processes called stopping, affricating, tensifying and palatalizing during the transitional period of phonological development by young children. Moreover, between the two voiceless types, /s/ was acquired earlier than /s'/ as the unmarked segment.

• Phonetics and Speech Sciences
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• v.2 no.3
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• pp.37-46
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• 2010

This study investigates acoustic characteristics of English and Korean voiceless sibilant fricatives as they appear before the three vowels, /i/, /$\alpha$/ and /u/. Three measurements - duration, center of gravity and major spectral peak - are employed to compare acoustic properties and vowel effect for each fricative sound. This study also investigates the question of whether Korean sibilant fricatives are acoustically similar to the English voiceless alveolar fricative /s/ or to the palato-alveolar /$\int$/. The results show that in the duration of frication noise, English /$\int$/ is the longest and Korean lax /s/ the shortest of the four sounds. It is also observed that English alveolar /s/ has the highest value, whereas Korean /s/ shows the lowest value in the frequency of center of gravity. In terms of major spectral peak, while English /s/ reveals the highest frequency, English /$\int$/ shows the lowest value. In addition, evidence indicates that there is a strong vowel effect in the fricative sounds of both languages, although the vowel effect patterns of the two languages are inconsistent. For instance, in the major spectral peak, both Korean lax /s/ and tense /$s^*$/ show significantly higher frequencies before the vowel /$\alpha$/ than before the other vowels, whereas both English /s/ and /$\int$/ exhibit significantly higher frequencies before the vowel /i/ than before the other vowels. These results indicate that Korean sibilant fricatives are acoustically distinct from both English /s/ and /$\int$/.

• Speech Sciences
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• v.12 no.1
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• pp.89-105
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• 2005

This paper is a production study of the effects of Korean prosody on two voiceless coronal fricatives /$s^h$/ and /s*/. The target segments were embedded in four prosodic positions: initial to the Intonational Phrase or the Accentual Phrase, and medial to the Accentual Phrase or to the Prosodic Word. Acoustic measurements showed that the durational differences associated with the /$s^h$/ versus /s*/ contrast vary in magnitude in different prosodic positions, confirming the proposal that segmental properties are affected by prosodic categories. This suggests that any speech synthesizer should take into consideration prosodically conditioned durational variation.

• Speech Sciences
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• v.4 no.1
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• pp.135-145
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• 1998

An Electropalatographic (EPG) study was conducted to investigate the articulatory characteristics which determine the, distinction between the Korean lax fricative [s] and tense fricative [s']. This study also intended to test if an increase in the degree of tensity (lax fricative [s] < tense fricative [s']) induces a decrease in coarticulatory vocalic effects. The results indicated that the increase in the tensity of Korean fricatives is closely related to the increase in the narrowness of the groove width (wider contact at the place of articulation), the forward shifting in the place of articulation, and the longer duration of the constriction (longer maintenance in the manner of articulation). It was also found that coarticulatory vocalic effects on Korean fricatives are affected by Recasens' two rules of constraint (1983) : spatial and temporal constraints.

• Phonetics and Speech Sciences
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• v.4 no.3
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• pp.3-12
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• 2012

The primary goal of the current study was to examine category solidity of Korean alveolar fricatives in the Busan and Seoul dialects of Korean. Considering the common belief of $/s^h/-/s^*/$ neutralization in Kyungsang speech, plain $/s^h/$ and fortis $/s^*/$ fricatives of Busan speakers were examined against the same fricatives of Seoul speakers. Perceptual distance between Korean $/s^h/$ and $/s^*/$ on the one hand and English /s/ on the other was investigated by use of across-linguistic mapping method. Two experiments of a perceptual mapping task of English /s/ to Korean $/s^h/$ and $/s^*/$ and a $/s^*/$-production task were conducted on users of the Busan and Seoul dialects of Korean. The results from the perception and production experiments suggested that at a micro-level, younger Busan speakers have less solid category stability for Korean $/s^*/$ compared with Seoul speakers, although their production of $/s^h/$ and $/s^*/$ was as highly distinctive from each other as that of Seoul speakers.

• Phonetics and Speech Sciences
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• v.13 no.1
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• pp.25-36
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• 2021

This study examined the perception and production of eight English fricatives /f/, /v/, /θ/, /ð/, /s/, /z/, /ʃ/, and /ʒ/ by thirty Chinese English majors and thirty Chinese middle school students through a fricative identification test, an intelligibility test, and a goodness rating test and focused on error patterns and the perception-production relationship. The results showed that substitution errors occurred frequently in the perception and production of English fricatives by both the English majors and the middle school students. Further, the error patterns were attributed to various influencing factors such as the negative transfer from Chinese consonant inventory, hypercorrection or overcompensation mistakes, deficiency of L2 teaching, and acoustic similarities. Significant overall correlations were found between the fricative perception and production by the two subject groups but were not manifested in all the eight fricatives, indicating that Chinese learners' perceptual competence of target fricatives was not necessarily tied to their productive excellence of those sounds in all cases. Furthermore, precedences of perception over production were incompletely manifested in the eight fricatives, which suggested that perception might not always be a necessary prerequisite for production. Additionally, subject group and vowel context differences were observed. The English majors performed better than the middle school students, both perceptually and productively, and the subjects' performances in perception and production varied when vowel contexts changed.

• Phonetics and Speech Sciences
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• v.7 no.3
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• pp.117-128
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• 2015

This paper investigates the acoustic-perceptual relation between Korean dent-alveolar fricatives and the English voiceless alveolar fricative /s/ in varied prosodic contexts (e.g., stress, accent, and word initial position). The denti-alveolar fricatives in Korean show a two-way distinction, which can be referred to as either plain (lenis) /s/ or fortis /$s^*$/. The English alveolar voiceless fricative /s/ that corresponds to the two Korean fricatives would be placed in a one-to-two non-native phoneme mapping situation when Korean listeners hear English /s/. This raises an interesting question of how the single fricative of English perceptually maps into the two-way distinction in Korean. This paper reports the acoustic-perceptual mapping pattern by investigating spectral properties of the English stimuli that are heard as either /s/ or /$s^*$/ by Korean listeners, in order to answer the two questions: first, how prosody influences fricatives acoustically, and second, how the resultant properties drive non-native listeners to interpret them as segmental features instead of as prosodic information. The results indicate that Korean listeners' responses change depending on the prosodic context in which the stimuli are placed. It implies that Korean speakers interpret some of the information provided by prosody as segmental one, and that the listeners take advantage of the information in their judgment of non-native phonemes.

• Phonetics and Speech Sciences
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• v.11 no.3
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• pp.23-29
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• 2019

This study acoustically examines the quality of fricatives produced by ten dysarthric speakers with cerebral palsy. Previous similar studies tend to focus only on sibilants, but to obtain a better understanding of how dysarthria affects fricatives we selected a range of samples with different places of articulation and voicing. The Universal Access (UA) Speech database was used to select thirteen words beginning with one of the English fricatives (/f/, /v/, /s/, /z/, /ʃ/, /ð/). The following four measurements were taken for both dysarthric and healthy speakers: phoneme duration, mean spectral peak, variance and skewness. Results show that even speakers with mild dysarthria have significantly longer fricatives and a lower mean spectral peak than healthy speakers. Furthermore, mean spectral peak and variance showed significant group effects for both healthy and dysarthric speakers. Mean spectral peak and variance was also useful for discriminating several places of articulation for both groups. Lastly, spectral measurements displayed important group differences when taking severity into account. These findings show that in general there is a degradation in the production of fricatives for dysarthric speakers, but difference will depend on the severity of dysarthria along with the type of measurement taken.