• MALSORI
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• no.53
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• pp.1-16
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• 2005

This experimental study aims to test the hypothesis that the occurrence of English sentence-final stop release is, at least, partly predictable by examining its phonetic context. 10 native(5 male and 5 female) speakers of American English recorded, in a sound-proof booth, sentences excerpted from novels and the natural documents on the World Wide Web. Based on the waveforms and spectrograms of the recorded sentences, judgements of the release of a sentence-final stop were made. If the aperiodic energy of a given final stop lasted more than .015 second, it was considered to be "released." The result reveals that English sentence-final stops tend to be released when they are 1) velar consonants, 2) preceeded by tense vowels, and 3) coda consonants of content words. The phonetic environment in which final stops are often released can be characterized by the articulatory comfortableness and the need for release burst noise, without which the final stops may not be correctly perceived. By examining the release of English final stops, it is concluded that the phonological events, which had been considered to occur rather "randomly," in fact, reflect the universal tendency of human speech: to minimize the speakers' and hearers' effort.

• Phonetics and Speech Sciences
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• v.8 no.3
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• pp.11-20
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• 2016

It is well known that vowels are shorter before voiceless consonants than voiced ones in English, as in many other languages. Research has shown that the ratio of vowel durations in voiced and voiceless contexts in English is in the range of 0.6~0.8. However, little work has been done as to whether the ratio of vowel durations varies depending on English variety. In the production experiment in this paper, seven speakers from three varieties of English, New Zealand, British, and American English, read 30 pairs of (C)VC monosyllabic words which differ in coda voicing (e.g. beat-bead). Vowel height, phonemic vowel length, and consonant manner were varied as well. As expected, vowel-shortening effects were found in all varieties: vowels were shorter before voiceless than before voiced codas. Overall vowel duration was the longest in American English and the shortest in New Zealand (NZ) English. In particular, vowel duration before voiceless codas is the shortest in New Zealand English, indicating the most radical degree of shortening in this variety. As a result, the ratio of vowel durations in varying voicing contexts is the lowest in NZ English, while American and British English do not show a significant difference each other. In addition, consonant closure duration was examined. Whereas NZ speakers show the shortest vowel duration before a voiceless coda, their voiceless consonants have the longest closure duration, which suggest an inverse relationship between vowel duration and closure duration.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2016.05a
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• pp.293-296
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• 2016

Speech Signals consist of signals of consonants and vowels, but the lasting time of vowels is much longer than that of consonants. It can be assumed that the correlations between signal blocks in speech signal is very high. But the correlations between signal blocks in various frequency bands can be quite different. Each speech signal is divided into blocks which have 128 speech data. FFT is applied to each block. Various frequency areas of the results of FFT are taken and Covariance matrix between blocks in a speech signal is extracted and finally eigenvalues of those matrix are obtained. It is studied that in the eigenvalues of various frequency bands which band can be used to get more reliable result.

• The KIPS Transactions:PartB
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• v.10B no.2
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• pp.169-178
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• 2003

This study outlines two viewpoints the classification of phone likely unit (PLU) which is the foundation of korean large vocabulary speech recognition, and the effectiveness of Chiljongseong (7 Final Consonants) and Paljogseong (8 Final Consonants) of the korean language. The phone likely classifies the phoneme phonetically according to the location of and method of articulation, and about 50 phone-likely units are utilized in korean speech recognition. In this study auditory phonetical knowledge was applied to the classification of phone likely unit to present 45 phone likely unit. The vowels 'ㅔ, ㅐ'were classified as phone-likely of (ee) ; 'ㅒ, ㅖ' as [ye] ; and 'ㅚ, ㅙ, ㅞ' as [we]. Secondly, the Chiljongseong System of the draft for unified spelling system which is currently in use and the Paljongseonggajokyong of Korean script haerye were illustrated. The question on whether the phonetic value on 'ㄷ' and 'ㅅ' among the phonemes used in the final consonant of the korean fan guage is the same has been argued in the academic world for a long time. In this study, the transition stages of Korean consonants were investigated, and Ciljonseeng and Paljongseonggajokyong were utilized in speech recognition, and its effectiveness was verified. The experiment was divided into isolated word recognition and speech recognition, and in order to conduct the experiment PBW452 was used to test the isolated word recognition. The experiment was conducted on about 50 men and women - divided into 5 groups - and they vocalized 50 words each. As for the continuous speech recognition experiment to be utilized in the materialized stock exchange system, the sentence corpus of 71 stock exchange sentences and speech corpus vocalizing the sentences were collected and used 5 men and women each vocalized a sentence twice. As the result of the experiment, when the Paljongseonggajokyong was used as the consonant, the recognition performance elevated by an average of about 1.45% : and when phone likely unit with Paljongseonggajokyong and auditory phonetic applied simultaneously, was applied, the rate of recognition increased by an average of 1.5% to 2.02%. In the continuous speech recognition experiment, the recognition performance elevated by an average of about 1% to 2% than when the existing 49 or 56 phone likely units were utilized.

• Phonetics and Speech Sciences
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• v.1 no.1
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• pp.47-52
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• 2009

The speech of Sino-Korean has been evolved from geopolitical cause since 1945. The aim of this study is to collect Yanji dialectal speech and to compare with South Korean dialectal speech. Twenty Yanbian university students participated as informants. Acoustic speech informations are analyzed using the Multi-Speech Windows Vista version. Dialectal speech characteristics of Yanji sino-Korean showed posterior vowel /${\alpha}$/, neutralization of mid-vowel /o/ between /o/ and /Ɔ/. Lenis stop sound showed the tendency of glottalization based on VOT value. Sibilant sound contains aspiration following constriction and lateral /l/ realized the approximant /r/.

• Journal of the Korean Institute of Telematics and Electronics
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• v.26 no.9
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• pp.1340-1347
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• 1989

For the efficient recognition of Korean Alphabets, a tree structure discrimination algorithm employing NRF-SDF concept is proposed. This algorithm consists of several main-steps, which contain several sub-steps. Each step contains vowels or consonants for training image. This algorithm reduces processing and recognition time than any other conventional algorithms for recognition of Korean Alphabets. A simulation results indicated that this algorithm has a satisfactory performance.

• MALSORI
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• no.37
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• pp.13-21
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• 1999

This study, as a successive study of Ko(1998a) which investigates the effect of vowel length contrast on the voicing of the word-final consonants in English, examines if other phonetic features of word-final stops themselves affect the Perception of their voicing. They are closure duration, voicing status during closure period, release portion. 68 Korean students learning English as a second language in Wonkwang University participate as subjects for this study. The results showed that they are not important clues to Korean students to the voicing identification of the word-final stops in English.

• Proceedings of The Korean Cleft Lip And Palate Association
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• 1997.06a
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• pp.35-35
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• 1997

• The Journal of Korean Academy of Prosthodontics
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• v.30 no.3
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• pp.338-360
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• 1992

This study was performed to investigate the phonetic alterations with upper anterior teeth were missing. To compare the changes of the phonations, before and after insertion of the temporary prosthesis, six subjects who lost their upper anterior teeth were selected (2-male, 4-female). Tested sounds (/ga(가), na(나), da(다), ra(라), sa(사), ja(자), cha(차), ta(타), pa(파), ha(하), gi(기), ni(니), di(디), ri(리), si(시), jl(지), chi(치), ti(티), pi(피), hi(히), seu(스), se(세), so(소), su(수)/were programmed into an IBM AT with and without temporary prosthesis. These experiments were analyzed by formants, consonants durations, and energy level changes with an LSI speech work station program. During the pronunciation of the tested sounds (with and without temporary prosthesis), mandibular movements were recorded to a Mandibular Kinesiogram and analyzed . The findings led to the following conclusions: 1. Objective differences could not be found. However, in every informant, subjective improvement could be noticed. 2. There were no persistant correlations of the formant's changes. And in every informant, phonetic changes were variable. 3. There were various changes of the consonant durations in every informant. By and large, those of /si(시), jl(지), chi(치), Pi(피), hi(히)/ were longer than other tested sounds. After insertion of the prosthesis, durations were shorter. Consonants with /i(ㅣ)/ were longer than with /a(ㅏ)/, with or without prosthesis. 4. With and without temporary prosthesis, mandibular movements were various in the frontal view. Mandibular movements showed lateral deviations, and mandibular positions with /si(시), ji(지), ti(티), seu(스), hi(히)/ were nearer to the mandibular rest position. 5. The kinds of temporary prosthesis and conditions of the missing teeth influenced every informant variously, so there were no correlation between informants. 6. Energy levels increased in all tested sounds with a fixed temporary prosthesis. And, there were no differences between before and after insertion of a removable temporary prosthesis. However, sibilant sounds, and consonants with /i(ㅣ)/ showed a little increased energy level.

• Journal of Korean language education
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• v.28 no.4
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• pp.273-296
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• 2017

This study focuses on a review of Hangeul orthography guidelines in Korean language regulations. It is indispensable to revise the guidelines thoroughly because it has been more than 80 years since a unified plan of Korean orthography was established in 1933, which the current orthography is based on. Also, it has been approximately 30 years since 1989, when the current guidelines were issued and promulgated. The viewpoint towards this review reflects the requirements by education fields of Korean as a foreign language and modern Korean users. Hangeul orthography consists of six clauses, along with an appendix regarding punctuation marks: 1) general rules, 2) consonants and vowels, 3) related to sounds, 4) about forms, 5) spacing between words, and 6) miscellaneous. This paper examined individual clauses and specific usages of the clauses, in terms of Korean as a foreign language. Based on the review, this paper suggests the following tasks in order to establish a draft of Hangeul orthography for foreigners. A. Among the individual clauses, some clauses that embody vocabulary education aspects should be addressed in a Korean dictionary, and deleted in Hangeul orthography guidelines. B. The clauses of Hangeul orthography guidelines should be edited for revision and substitution where necessary. C. The usage of individual clauses should be replaced with more appropriate examples aligned with everyday conversation. D. In order to establish 'Hangeul orthography for foreigners', linguists should continuously review several chapters and the appendix of Hangeul orthography, such as components about forms, spacing between words, miscellaneous, and punctuation marks. The purpose of this review is to pursue the simplicity of Hangeul orthography guidelines and the practicality in terms of reflecting more realistic examples. This review contributes to facilitate Korean language usage not only for non-native learners, but also native users.