• Proceedings of the KSPS conference
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• 2007.05a
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• pp.149-151
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• 2007

This study was designed to investigate fast ab/adduction rate of articulation valves in normal adults. The measurement of fast ab/aduction rate has traditionally been used for assessment, diagnosis and therapy in patients who suffered from dysarthria, functional articulation disorders or apraxia of speech. Fast ab/adduction rate shows the documented structural and physiological changes in the central nervous system and the peripheral components of oral and speech production mechanism. Fast ab/adduction rates were obtained from 20 normal subjects by producing the repetition of vocal function (/ihi/), tongue function (/t${\wedge}$/), velopharyngeal function (/m/), and labial function (/p${\wedge}$/). The Aerophone II was used for data recording. The results of finding as follows: average fast ab/adduction rates were vocal function(6.21cps), tongue function(7.42cps), velopharyngeal function(5.23cps), labial function (6.93cps). The results of this study are guidelines of normal diadochokinetic rates. In addition, they can indicate the severity of diseases and evaluation of treatment.

• Proceedings of the Acoustical Society of Korea Conference
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• 1998.08a
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• pp.142-147
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• 1998

Recently, 8 kb/s CS-ACELP coder of G.729 is atandardized by ITU-T SG15 and it has been reported that the speech quality of G729 is better than or equal to that of 32kb/s ADPCM. However G.729 is the fixed rate speech coder, and it does not consider the property of voice activity in mutual conversation. If we use the voice activity, we can reduce the average bit rate in half without any degradations of the speech quality. In this paper, we propose an efficient variable rate algorithm for G.729. The variable rate algorithm consists of two main subjects, the rate determination algorithm and algorithm, we combine the energy-thresholding method, the phonetic segmentation method by integration of various feature parameters obtained through the analysis procedure, and the variable hangover period method. Through the analysis of noise features, the 1 kb/s sub rate coder is designed for coding the background noise signal. So, we design the 4 kb/s sub rate coder for the unvoiced parts. The performance of the variable rate algorithm is evaluated by the comparison of speed quality and average bit rate with G.729. Subjective quality test is also done by MOS test. Conclusively, it is verified that the proposed variable rate CS-ACELP coder produced the same speech quality as G.729, at the average bit rate of 4.4 kb/s.

• Proceedings of the KSPS conference
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• 2000.07a
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• pp.47-58
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• 2000

For the learners of English as a foreign language, oral repetition of model sentences is an e essential practice to improve their listening and speaking abilities of English. Skill training of both speech perception and production is involved in this practice. This paper reports on an observation of production e$\pi$ors in such practice made by Japanese college students in my class. The teaching material used is intended for acquainting the learners with basic English rhythm and intonation p patterns. The students were required to repeat each sentence in a series of conversations after a model reading. Although the vocabulary and expressions were rather limited, I monitored different kinds of errors in their repetition. Putting aside intonation, their difficulties are classified into five types; 1. Omission of words or morphemes, 2. Addition of unnecessary words or morphemes, 3. Replacement of words, 4. Japanization of English sounds, 5. Wrong rhythm caused by improper stress assignment. Accurate listening, especially to weakly stressed syllables and to assimilated sounds, as has often been pointed out, is the most difficult part in perception for them. Japanese sound system interferes in production of English sounds. More often than not their knowledge of grammar or the context does not work at all to guess the words they are hearing

• Korean Journal of Child Studies
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• v.26 no.4
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• pp.145-155
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• 2005

This study was carried out to reveal Hangul acquisition processes in Korean-Chinese children who grow in a horizontal bilingual environment. In this experiment Grapheme substitution/deletion tasks and sensible/non-sensible Kulja reading tasks were administered to 3-, 4-, 5- and 6-year-old Korean-Chinese children growing up in a bilingual environment. Results were that Korean-Chinese children showed similar patterns of Hangul acquisition processes to Korean children but acquired grapheme-phoneme(G-P) correspondence earlier than Korean children. Hangul acquisition rates were 41.7%, 45.7%, 53% and 92.7% at age 3, 4, 5 and 6, respectively. Both Korean-Chinese and Korean children showed higher sensitivity for the final consonant than for the initial and middle consonants. Correlation between phoneme perception and reading was only significant among 6-year-olds in non-sensible Kulja reading tasks. Training in transforming ideographic Chinese to a phonetic system could effect early acquisition of G-P correspondence in Korean-Chinese children.

• Speech Sciences
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• v.9 no.2
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• pp.25-47
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• 2002

Human language activity in the information society has been developing the communication system between humans and machines. The aim of this study was to analyze dialectal speech in Korea. One hundred Kyungsang and one hundred Cholla informants participated in this study. A CSL and Flexible laryngeal fiberscope were used for analysis of the acoustic and glottal gestures of all the vowels and consonants. Test words were made on the picture cards and letter cards which contained each vowel and each consonant, respectively. The dialogue between the examiner and the informants was recorded in a question and answer manner. The acoustic results of two dialects were as follows: Kyungsang and Cholla informants showed neutralization between /e/ and /$\varepsilon$. However, the apertures of Kyungsang vowels /i, w, u, o/ were higher than those of Cholla vowels. The /wi/ and /$\varepsilon$/ of Kyungsang Diphthong vowels were shown as simple vowels /i/ and /$\varepsilon$/ in Cholla dialect. The VOT of Cholla dilaect was longer than that of Kyungsang dialect. The fricative frequence of Kyurlgsang dialect was about 1000Hz higher than that of Cholla dialect. The glottal widths on fiberscopic images showed that the consonant durations of Kyungsang and Cholla dialects were correlated all together with the acoustic duration on the spectrogram.

• Speech Sciences
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• v.1
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• pp.213-223
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• 1997

This paper deals with a general review of Mieko S. Han, who made a significant contribution to the studies of Korean phonetics during the 1960' s and early 1970' s. As both a single and joint author, Dr. Han published important papers in both quantity and quality, which have been cited among Korean phoneticians until today. Before Dr. M. Han' s work, professor of USC in the department of East Asian Languages & Cultures, there were only a few phonetics-related publications in Korea, most of which are papers or books based on non-experimental traditional approach. It is known that there was coexistence between traditionalism and structuralism in the field of Korean linguistics. It was, however, fortunate that we had two important phoneticians (M. Han and Chin-W Kim) abroad at that time. Mieko Han' s concern was to investigate experimental characteristics of the system of Korean vowels and consonants using a Spectrograph, which was the single most important tool for analysing phonetic data at that time. Dr. Han conducted her experimental studies on Korean phonetics, mostly funded by the Office of Naval Research, in terms of duration, fundamental frequency, Voice Onset Time (VOT), intensity, and so on. This paper aims to re-appreciate Dr. Han's specific contribution to the study of Korean phonetics since she played an important role as a pioneer of early Korean phonetics. Further, it is highly recommended that Dr. Han's works can be extremely useful for a graduate student, who seriously would like to specialize in Korean phonetics in the first step.

• Phonetics and Speech Sciences
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• v.9 no.2
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• pp.9-22
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• 2017

The purpose of this paper is to report the whole process of developing Korean Standard Speech Database (KSS DB). This project is supported by SPO (Supreme Prosecutors' Office) research grant for three years from 2014 to 2016. KSS DB is designed to provide speech data for acoustic-phonetic and phonological studies and speaker recognition system. For the samples to represent the spoken Korean, sociolinguistic factors, such as region (9 regional dialects), age (5 age groups over 20) and gender (male and female) were considered. The goal of the project is to collect over 3,000 male and female speakers of nine regional dialects and five age groups employing direct and indirect methods. Speech samples of 3,191 speakers (2,829 speakers and 362 speakers using direct and indirect methods, respectively) are collected and databased. KSS DB designs to collect read and spontaneous speech samples from each speaker carrying out 5 speech tasks: three (pseudo-)spontaneous speech tasks (producing prolonged simple vowels, 28 blanked sentences and spontaneous talk) and two read speech tasks (reading 55 phonetically and phonologically rich sentences and reading three short passages). KSS DB includes a 16-bit, 44.1kHz speech waveform file and a orthographic file for each speech task.

• The Journal of the Acoustical Society of Korea
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• v.16 no.2
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• pp.49-57
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• 1997

In this paper, we propose the stochastic pronunciation lexicon model for large vocabulary continuous speech recognition system. We can regard stochastic lexicon as HMM. This HMM is a stochastic finite state automata consisting of a Markov chain of subword states and each subword state in the baseform has a probability distribution of subword units. In this method, an acoustic representation of a word can be derived automatically from sample sentence utterances and subword unit models. Additionally, the stochastic lexicon is further optimized to the subword model and recognizer. From the experimental result on 3000 word continuous speech recognition, the proposed method reduces word error rate by 23.6% and sentence error rate by 10% compare to methods based on standard phonetic representations of words.

• The Journal of the Acoustical Society of Korea
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• v.26 no.1E
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• pp.1-7
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• 2007

One result of the trend towards globalization is an increased number of projects that focus on natural language processing. Automatic speech recognition (ASR) technologies, for example, hold great promise in facilitating global communications and collaborations. Unfortunately, to date, most research projects focus on single widely spoken languages. Therefore, the cost to adapt a particular ASR tool for use with other languages is often prohibitive. This work takes a more general approach. We propose an International Phoneticizing Engine (IPE) that interprets input files supplied in our Phonetic Language Identity (PLI) format to build a dictionary. IPE is language independent and rule based. It operates by decomposing the dictionary creation process into a set of well-defined steps. These steps reduce rule conflicts, allow for rule creation by people without linguistics training, and optimize run-time efficiency. Dictionaries created by the IPE can be used with the Sphinx speech recognition system. IPE defines an easy-to-use systematic approach that can lead to internationalization of automatic speech recognition systems.

• Journal of Animal Science and Technology
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• v.47 no.1
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• pp.133-140
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• 2005

The aim of this study was to divide vocalizations of sows into general(GVs) and estrus-related vocalizations( EVs) and to find out their phonetic characteristics. Ten sows(Landrace) were recorded using digital video recorders twice daily(06: 00 - 08 : 00h and 17: 00 - 19 : 00h) during the anestrus and estrus periods. The GVs and EVs were divided based on the shapes of spectrum and spectrogram. The GVs and EVs were identified as 5 and 3 types, respectively. Pitch, formant I, formant 2, and formant 3 between GVs and EVs were not significantly different(P> 0.05), whereas intensity(P < 0.001), duration(P < 0.05), and formant 4(P < 0.01) were significantly different. Three parameter groups(Group I : Formant vector alone, Group II: Formant veetor+ parameters from time signal, Group III: Formant vector+parameters from time signal-parameters eliminated by stepwise discriminant analysis backward) were compared by discriminant function analysis. The classification system adopted in the Group II represented the higher discrimination rate than those in other groups(Group I : 76.1 0/0, Group II : 88.1 0/0, Group Ill: 87.3 %). These results suggest that EVs are present and intensity, formant 2, and formant 4 are available parameters for discrimination of EVs in sows.