• 말소리와 음성과학
• /
• 제10권1호
• /
• pp.15-22
• /
• 2018

Stressed vowels in English are usually produced using longer duration, higher pitch, and greater intensity than unstressed vowels. However, many English as a foreign language (EFL) learners have difficulty producing English lexical stress because their mother tongues do not have such features. In order to investigate if certain non-native English speakers (Korean, Japanese, and Taiwanese-Chinese native speakers) are able to produce English lexical stress in a native-like manner, speech samples were extracted from the L2 learners' corpus known as AESOP (the Asian English Speech cOrpus Project). Sixteen disyllabic words were analyzed in terms of the ratio of duration, pitch, and intensity. The results demonstrate that non-native English speakers are able to produce English stress in a similar way to native English speakers, and all speakers (both native and non-native) show a tendency to use duration as the strongest cue in producing stress. The results also show that the duration ratio of native English speakers was significantly higher than that of non-native speakers, indicating that native speakers produce a bigger difference in duration between stressed and unstressed vowels.

• 영어어문교육
• /
• 제17권4호
• /
• pp.251-271
• /
• 2011

The present study analyzed Korean learners' production of English /z/-/$d{\Box}$/ and /z/-/${\Box}$/ contrasts in terms of native speaker judgments and acoustic measurements. Korean learner's production was judged to be either correct or incorrect by native English speakers. Correct and incorrect productions were then compared with productions of native speakers' in terms of acoustic analyses. The results indicated that Korean speakers' correct production was more similar to that of native speakers by sharing more acoustic cues. Incorrect production by Korean speakers indicated patterns either different or opposite from that of native speakers, confirming native speaker judgments. The results also revealed acoustic cues on which native speakers rely in judging L2 speech, thereby implying that the more consistent along with more number of acoustic cues used by native speakers may facilitate the acquisition of segment contrasts by L2 learners.

• 말소리와 음성과학
• /
• 제3권1호
• /
• pp.15-22
• /
• 2011

The purposes of this study are (1) to investigate the correlation between English word-final stop and the duration of vowels before word-final stop and (2) to suggest a way to detect pronunciation errors and teach the pronunciation of English word-final stops. For these purposes, 18 Korean speakers' production was recorded and analysed using Speech Analyzer and their production was compared with that of native English speakers. In addition, two native English speakers evaluated the subjects' pronunciation. The major findings are the voicing dependent effect of the English vowels produced by native Korean speakers is lower than that of native English speakers; Korean speakers release English word-final stops less than native English speakers; and the pronunciation of English word-final stops and the duration of adjacent vowels are closely related in that the pronunciation score of final stops and the ratio of vowels between the vowels before voiced stops and voiceless stops are correlated. In addition, this study concludes with pedagogical suggestions that may be useful for English pronunciation teaching.

• 대한음성학회:학술대회논문집
• /
• 대한음성학회 2000년도 7월 학술대회지
• /
• pp.332-332
• /
• 2000

The purpose of this study is to investigate the perception and production of English vowels by native speakers of Korean. In perception test, twelve English vowels /${\ae},{\;}a,{\;}{\Game},{\;}e,{\;}{\varepsilon},{\;}i,{\;}I,{\;}a,{\;}o,{\;}u,{\wedge},{\;}{\mho}$/, as in had, hard, hoard, hayed, head, heed, hid, hod, hoed, whod, Hudd, and hood produced by native speakers of English were used as perception test materials and subjects were asked to identify the vowels. Two different groups of subjects participated in the perception test. One consisted of 90 students who were taking an English phonetics course, and the other consisted of 64 who were not. The results showed that the former did better than the latter m identifYing English vowels, and that vowels in 'head' and 'had' were relatively hard to identify, while vowels in 'hayed', 'hard', and unexpectedly, 'heed' and hid' were easy to perceive. In production test, two native English speakers and 4 native Korean speakers served as subjects. The 4 native Korean speakers were divided into two groups as in the perception test, experienced and inexperienced, depending on whether they were taking an English phonetics course or not. Native English speakers generally showed significant differences both in vowel duration and in FI & F2 values between members of the vowel pairs which are of special interest of this study: /i/ vs. /I/, /${\ae}$/ vs. /$\varepsilon$/, and /u/ vs. and /$\mho$/. There was no significant difference between the two Korean groups. Native Korean speakers showed much difference in neither duration nor FI & F2 values except significant durational difference in /i/ vs. /I/ pair.

• 음성과학
• /
• 제10권2호
• /
• pp.223-236
• /
• 2003

The purpose of this experimental study is to investigate characteristics of English pitch accents uttered by Korean speakers. Six English sentences were uttered five times by fifteen male undergraduate and graduate students from three groups, Seoul, Yongnam and Honam dialect speakers. We compared the subjects' data with the data of a native speaker of English as model pronunciation of English pitch accents. Acoustic features(Fo, duration, amplitude) were measured from sound spectrograms made by the PC Works. Results showed that (1) acoustic features of English pitch accents are Fo and duration for the native speaker and Korean speakers altogether, (2) Seoul dialect speakers uttered English pitch accents more similarly to the English native speaker than the other dialect speakers and (3) Korean speakers generally have difficulties in pronouncing L* accents. It appears that Korean speakers have more problems in pronouncing L* accents than H* accents.

• 음성과학
• /
• 제9권4호
• /
• pp.215-234
• /
• 2002

This study is designed for two purposes. The first one is to compare the realization and perception of English contrastive focus between Korean learners of English and native speakers of English. The second purpose is to study the phonological and phonetical features of contrastive focus by examining the results of production and perception experiments. English native speakers' results show that the English contrastive accents are generally accompanied by higher peak heights. The findings agree with the results of Bartels & Kingston (1994). Unlike native speakers of English, Korean speakers seem to be poor at relating the phonetical features of contrastive focus to their actual speech. Korean speakers' results are especially unsuccessful when the contrast is not distinctly grasped through syntactic structure, or when the function words are contrasted. Furthermore, Korean speakers' utterances tend to have pitch accents on every content word, whether the word is contrasted or not.

• 음성과학
• /
• 제12권3호
• /
• pp.175-183
• /
• 2005

In this study, realization of strong and weak syllables in English by Korean leaners with low English proficiency was examined through experiment. The aspects of three acoustic characteristics-duration, pitch, amplitude-were measured and compared with native speakers of English. It was assumed that production of duration, pitch and amplitude of strong and weak syllable by Korean learners would be different from that of English native speakers. According to the production experiments, English native speakers produced strong syllable longer, higher and louder than weak syllable. However, Korean leaners produced strong syllable higher and louder than weak syllable, but not longer enough. Specifically, weak syllable by Korean leaners was longer and strong syllable shorter than native speakers. Furthermore, the difference in duration of syllables between Korean leaners and English native speakers is more significant than pitch and amplitude. As a result, the duration was more important cue for the realization of stress than pitch and amplitude. However, Korean leaners did not produce duration of stressed syllables as English native speakers did, even though they produce the pitch and amplitude of stressed syllable in a similar way to native speakers. The reasons for those were considered, too.

• 말소리와 음성과학
• /
• 제3권3호
• /
• pp.77-88
• /
• 2011

Foreign accent in second language production depends heavily on the transfer of features from the first language. This study examines acoustic variations in segments and suprasegments by native and nonnative speakers of English, searching for patterns of the transfer and plausible indexes of foreign accent in English. The acoustic variations are analyzed with recorded read speech by 20 native English speakers and 50 Korean learners of English, in terms of vowel formants, vowel duration, and syllabic variation induced by stress. The results show that the acoustic measurements of vowel formants and vowel and syllable durations display difference between native speakers and nonnative speakers. The difference is robust in the production of lax vowels, diphthongs, and stressed syllables, namely the English-specific features. L1 transfer on L2 specification is found both at the segmental levels and at the suprasegmental levels. The transfer levels measured as groups and individuals further show a continuum of divergence from the native-like target. Overall, the eldest group, students who are in the graduate schools, shows more native-like patterns, suggesting weaker foreign accent in English, whereas the high school students tend to involve larger deviation from the native speakers' patterns. Individual results show interdependence between segmental transfer and prosodic transfer, and correlation with self-reported proficiency levels. Additionally, experience factors in English such as length of English study and length of residence in English speaking countries are further discussed as factors to explain the acoustic variation.

• 말소리와 음성과학
• /
• 제4권3호
• /
• pp.59-73
• /
• 2012

This study attempts to investigate the contribution of prosody to the foreign accent in Chinese speakers' English production by examining the synthesized speech of crossing native and non-native talkers' prosody and segments. For the stimuli of the foreign accent ratings, we transplanted gender-matched native speakers' prosody onto non-native talkers' segments and vice versa, utilizing the TD-PSOLA algorithm. Eight English native listeners participated in judging foreign accent and comprehensibility of the transplanted stimuli. Results showed that the synthesized stimuli were perceived as stronger foreign accent regardless of speakers' proficiency when English speakers' prosody was crossed with Chinese speakers' segments. This suggests that segments contribute more than prosody to native listeners' evaluation of foreign accent. When transplanted with English speakers' segments, Chinese speakers' prosody showed a difference in duration rather than pitch between high and low proficiency such that stronger foreign accent was detected when low proficient Chinese speakers' duration was crossed with English speakers' segments. This indicated that prosody, more specifically duration, plays a role though the prosodic role is not overall as significant as segments. According to the post acoustic analysis, the temporal features contributing to making the duration parameter prominent as opposed to pitch were found out to be speaking rate, pause duration and pause frequency. Finally, foreign accent and comprehensibility showed no significant correlation such that native listeners had no difficulty listening to highly foreign accented speech.

• 말소리와 음성과학
• /
• 제2권4호
• /
• pp.101-107
• /
• 2010

This study investigates the difference in the evaluation of English pronunciation quality between native speakers of English and Korean learners of English. This study employs a novel method of independently evaluating the prosody and segmentals of English sentences. A set of stimuli were made by swapping the prosody and the segmentals of English sentences read by a native speaker of American English and a Korean learner of English. Evaluations of the difference level of stimuli pairs and the goodness of the pronunciation quality showed that both native speakers of English and Korean learners of English give priority to the segmentals but native speakers of English were more sensitive to the difference in prosody in the evaluation of English pronunciation.