• The Transactions of the Korean Institute of Electrical Engineers
• /
• v.40 no.4
• /
• pp.360-373
• /
• 1991

Since 70's, efficient speech recognition methods such as HMM or DTW have been introduced primarily for speaker dependent isolated words. These methods however have confronted with difficulties in recognizing continuous speech. Since early 80's, there has been a growing awareness that neural networks might be more appropriate for English and Japanese phoneme recognition using neural networks. Dealing with only a part of vowel or consonant set, Korean phoneme recognition still remains on the elementary level. In this light, we develop a system based on neural networks which can recognize major Korean phonemes. Through experiments using two neural networks, SOFM and TDNN, we obtained remarkable results. Especially in the case of using TDNN, the recognition rate was estimated about 93.78% for training data and 89.83% for test data.

• Speech Sciences
• /
• v.9 no.3
• /
• pp.201-210
• /
• 2002

This paper explores whether there is correlation between consonants' place and duration of adjacent vowels in English and Korean. The results showed that in English the vowels preceding alveolar stops were in general longer than the vowels before bilabial or velar stops. Consonants appeared to have their inherent length due to their place and to exhibit some compensatory effects on the duration of preceding vowels. This effect can be explained in a physiological term that the tongue tip is the organ which might be more agile in articulatory movement than the tongue body for the velars or the lower lip (and the jaw) for the bilabials is and the shorter production time of the alveolars caused the lengthening of the adjacent vowels. However, this physiological account did not hold in the case of Korean, which exhibited less consistent patterns across speakers for the consonants' place and the vowel duration. The segmental duration seemed to be timed quite consistently within a language but the pattern was not universal across languages.

• Phonetics and Speech Sciences
• /
• v.8 no.4
• /
• pp.9-14
• /
• 2016

This study investigated the patterns of coda deletion in spontaneous Seoul Korean speech. More specifically, the current study focused on three factors in promoting coda deletion, namely, word position, consonant type, and morpheme type. The results revealed that, first, coda deletion frequently occurred when affixes were attached to the ends of words, rather than in affixes in word-internal positions or in roots. Second, alveolar consonants [n] and [l] in the coda positions of high-frequency affixes [nɨn] and [lɨl] were most likely to be deleted. Additionally, regarding affix reduction in the word-final position, all subjects seemed to depend on this articulatory strategy to a similar degree. In sum, the current study found that affixes without primary semantic content in spontaneous speech tend to undergo the process of reduction, favoring the occurrence of specific pronunciation variants.

• Proceedings of the KSPS conference
• /
• 2007.05a
• /
• pp.99-101
• /
• 2007

This study analyzes Korean middle school students' pronunciation errors of stop-liquid sequences in English. The results showed two typical errors: the insertion of a vowel between a stop and a liquid and the substitution of a liquid with a flap or vice versa. Those pronunciation errors seem to occur since English and Korean have different syllable structures and different types of liquids. A teaching material, which emphasizes no vowel insertion for a proper pronunciation of the consonant clusters, was designed to reduce Korean students' pronunciation errors. Errors were reduced substantially after a 50-minute class with the newly designed material.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.14 no.6
• /
• pp.686-698
• /
• 1989

In this paper, The new algorithm of spectrum moment for format frequency estimation is proposed. The second oder and the third order spectrum moment, which reflect variance and skewness of a spectrum pattern, respectively, is utilized to adjust the frequency region for estimation precision of format frequency. As the results. the F1-F2 diagram reported 8 Korean vowels for man and woman and that we found articulation method of vowel and vowel, vowel and consonant.

• Speech Sciences
• /
• v.9 no.4
• /
• pp.131-142
• /
• 2002

Place assimilation in Korean has been argued to reflect the consonantal strength hierarchy in which velar is stronger than labial which is in turn stronger than coronal. The strength relationship has been manifested in two ways in literature. One is through phonological representation as shown in Iverson and Lee (1994). The other is through perceptual salience ranking as suggested by Jun (1995). The goal of this study is to examine the perceptual salience of placed consonants through an identification experiment. The experiment conducted in this study reveals four facts. First, place identification of a prevocalic consonant is higher than that of a postvocalic one. Second, place identification of a stop in coda is more confusable than that of a nasal counterpart in Korean contrary to other previous studies. Third, velar is most confusable in place identification in contrast to Jun (1995) and Hume et al. (1999). Finally, place perception of consonants can vary depending on adjacent vocalic context. These results suggest that perceptual salience is one of the possibly several factors affecting a phonological process.

• Speech Sciences
• /
• v.7 no.3
• /
• pp.21-33
• /
• 2000

There are two hypotheses with reference to voicing in Korean intervocalic lax stops /p, t, k/ and affricate /c/: (1) the phonologically voiceless lax stops /p, t, k/ and affricate /c/ are realised as voiced allophones in the intervocalic position; (2) the shorter the lax consonant, the higher the percentage of voicing. But the literature reveals that there are views rejecting or doubting them. To clarify these, an experiment was carried out, using a Sun Sparcstation, twelve native speakers of Korean and speech materials embedded in a sentence frame. The results showed that the extent of voicing in lax stops and affricate was too inconsistent to support the full voicing hypothesis, and shorter duration (faster speech) did not necessarily cause a higher percentage of voicing.

• Speech Sciences
• /
• v.13 no.3
• /
• pp.121-132
• /
• 2006

In Hangeul, the graphemes of syllables are organized in horizontal, vertical and mixed (both horizontal & vertical) orientations, and the graphemic position of consonant(s) and vowel(s) within a each syllable needs to be maintained within a square pattern. We investigated the characteristics of writing errors of 9 stroke patients with right hemisphere (RH) lesions and compared it to the performances of 15 normal subjects. The subjects were asked to write to dictation of 90 Korean syllables. One of the interesting findings was that our patients manifested visuospatial errors which are not commonly observed in other language-speaking (e.g., English) patients due to the unique syllabic organizations of Korean writing system. The prominent errors in the RH group could be explained by the impaired RH which normally controls the visuospatial functions.

• Proceedings of the KSPS conference
• /
• 2002.11a
• /
• pp.129-132
• /
• 2002

Aerodynamic analysis study was performed on 14 normal subjects(2 male, 12 female) by nonsense syllables composed of Korean bilabial stop(/p, p', $p^{h}$) and their preceding and/or following vowel /i, a, u/. That is [pi, p'i, phi, pa, p'a, pha, pu, p'u, $p^{h}u$]. All measures were analysed using Aerophone II voice function analyzer and included peak air pressure, mean air pressure, maximum flow rate, volume, mean SPL. As results, first, MSPL and MAP of /p, p', $p^{h}$/ themselves were significantly different. In addition, different vowel enviroment also produced significantliy different aerodynamic chracteristics those consonants.

• Proceedings of the Korean Society for Cognitive Science Conference
• /
• 2006.06a
• /
• pp.43-46
• /
• 2006

본 연구는 단기종단연구로 4세와 5세 아동의 읽기, 받아쓰기와 자모 지식과의 관계를 연구하였다. 아동들을 시기 1에서 측정한 7개월 후에 다시 측정하였다. 회귀분석에서, 시기 1(T1)에 측정한 단어 읽기가 시기 2(T2)의 자음 이름과 자음 소리 지식을 예측하였다. 반면에 초성탈락, 숫자명명, 단어읽기가 모음 소리지식을 예측하였다. T2의 한글읽기를 예측하는 변인은 T1 한글읽기와 자음이름이었다. 반면에, 모음소리 지식과 초성탈락은 한글단어의 받아쓰기를 잘 예측할 수 있었다. 본 결과는 한글 자음과 모음 지식의 발달양식이 다르며, 이들이 한글읽기와 쓰기에 미치는 역할이 다른 것을 시사한다.