• The Journal of the Acoustical Society of Korea
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• v.15 no.4E
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• pp.28-36
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• 1996

In this paper, we propose a new evaluation methodology which can more clearly show the performance of the allophone modeling algorithm generally used in large vocabulary speech recognition. The proposed evaluation method shows the running characteristics and limitations of the modeling algorithm by testing how the variation of phonetic environments of training data affects the recognition performance and the desirable number of free parameters to be estimated. Using the method, we experiment results, we conclude that, in vocabulary-independent recognition task, the phonetic diversity of training data greatly affects the robustness of model, and it is necessary to develop a proper measure which can determine the number of states compromizing the robustness and the precision of the HMnet better than the conventional modeling efficiency.

• Phonetics and Speech Sciences
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• v.5 no.1
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• pp.99-108
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• 2013

Previous laboratory studies have shown that prosodic structures are encoded in the modulations of phonetic patterns of speech including suprasegmental as well as segmental features. In particular, effects of prosodic context on duration and intensity of syllables and words have been widely reported. Drawing on prosodically annotated large-scale speech data from the Buckeye corpus of conversational speech of American English, the current study attempted to examine whether and how prosodic prominence and phrase boundary of everyday conversational speech, as determined by a large group of ordinary listeners, are related to the phonetic realization of duration and intensity. The results showed that the patterns of word durations and intensities are influenced by prosodic structure. Closer examinations revealed, however, that the effects of prosodic prominence are not the same as those of prosodic phrase boundary. With regard to intensity measures, the results revealed the systematic changes in the patterns of overall RMS intensity near prosodic phrase boundary but the prominence effects are restricted to the nucleus. In terms of duration measures, both prosodic prominence and phrase boundary are the most closely related to the lengthening of the nucleus. Yet, prosodic prominence is more closely related to the lengthening of the onset while phrase boundary lengthens the coda duration more. The findings from the current study suggest that the phonetic realizations of prosodic prominence are different from those of prosodic phrase boundary, and speakers signal different prosodic structures through deliberate modulations of the internal phonetic structure of words and listeners attend to such phonetic variations.

• Speech Sciences
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• v.10 no.2
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• pp.259-280
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• 2003

The paper discusses the way in which speech sounds are being evaluated and transcribed in various fields of speech sciences, and suggests ways for a more accurate transcription. The academic fields explored are of phonetics, speech processing, speech pathology, and foreign language education. The discussion centers on the International Phonetic Alphabet (IPA), most commonly used in these fields, and other less widely-accepted transcription conventions such as the TOnes and Break Indices (ToBI), the Speech Assessment Methods Phonetic Alphabet (SAMPA), an extension of the official Korean Romanization (KORBET), and the American-English transcription system in the TIMIT database (TIMITBET). These transcription conventions are dealt with Korean, English, and Korean-accented English. The paper demonstrates that each transcription can exclusively be recommended for a specific need from different academic fields. Due to its publicity, the IPA is best suited for phonetic evaluation in the fields of phonetics, speech pathology, and foreign language education. The rest of the transcriptions are useful for keyboard-inputting the phonetically evaluated data from all these fields as well as for sound transcription in speech engineering, because they use convenient letter symbols for typing, searching, and programming. Several practical suggestions are made to maintain the transcriptional efficiency and consistency to accommodate the intra-and inter-transcriber variability.

• Cross-Cultural Studies
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• v.21
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• pp.255-270
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• 2010

Chinese phonology is called 'juexue(絶學)' in Chinese linguistics field. For this, students of in Chinese universities as well as college students in Korea is unwilling to learn it. Chinese character phonetic is a very valuable resource in Sino-China comparative study as well as the Chinese phonology area. This study was attempt to develop the content model on education of Chinese phonology, such as Middle Chinese, Old Chinese, using close the data of Chinese character phonetic for students of Korea. In addition, I also make it known that contents of this paper is not a new discovery or analysis but recycling research of existing.

• Proceedings of the KIEE Conference
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• 1987.07b
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• pp.1606-1609
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• 1987

Statistical information about spoken Korean was obtained. The data are the results of analyzing the Korean phonetic dictionary. This is one of the basic survey to make phoneme ballanced corpus of Korean Speech Data Base (KSDB).

• The Journal of the Acoustical Society of Korea
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• v.20 no.8
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• pp.24-30
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• 2001

This article is concerned with automatic segmentation for Korean speech signals. All kinds of transition cases of phonetic units are classified into 3 types and different strategies for each type are applied. The type 1 is the discrimination of silence, voiced-speech and unvoiced-speech. The histogram analysis of each indicators which consists of wavelet coefficients and SVF (Spectral Variation Function) in wavelet coefficients are used for type 1 segmentation. The type 2 is the discrimination of adjacent vowels. The vowel transition cases can be characterized by spectrogram. Given phonetic transcription and transition pattern spectrogram, the speech signal, having consecutive vowels, are automatically segmented by the template matching. The type 3 is the discrimination of vowel and voiced-consonants. The smoothed short-time RMS energy of Wavelet low pass component and SVF in cepstral coefficients are adopted for type 3 segmentation. The experiment is performed for 342 words utterance set. The speech data are gathered from 6 speakers. The result shows the validity of the method.

• Journal of Korean language education
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• v.28 no.2
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• pp.37-60
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• 2017

This research has its basis with focus on the way Korean native speakers recognize Chinese Korean-learners' pronunciation. The objective of the study is to lay the cornerstone for establishing effective teaching-learning strategies for the education of the Korean phonetic system. In this study, the results of the experiment are presented which shows how native speakers of Korean identify Chinese Korean-learners' pronunciation of consonants. In the first place, stimulation tones were created from the original utterances of Chinese Korean-learners and seven scripts were made through the Pratt program. In addition, the subjects were asked to choose what the phonetic materials sounded like. The results of the research are represented as the ratio of frequency of Korean native speakers' response to each utterance to the total frequency. In addition, the paired t-test was taken in order to explore any relatedness to the changes in the level of proficiency of the Korean phonetic system, ranging from beginners to advanced learners. The outcome shows that the mistakes which Chinese Korean-learners make in pronouncing the consonants of Korean are relatively well-reflected in Korean native speakers' auditory cognitive reactions. To put it concretely, there is some difficulty in differentiating lax consonants from aspirates in the cases of plosives and affricates, but relatively little trouble with fortes. However, it is revealed that there is also a slight difference in relation to articulatory positions in detailed aspects. To provide an effective teaching method for the Korean phonetic system, it is essential to comprehend learners' phonetic mistakes through the precise analysis of data in terms of 'production.' Also, a more meticulous observation of 'phenomena' must be made through verification from the view of 'reception,' as attempted in this study. A more thorough diagnosis by applying methodology makes it possible to lay the foundation for developing effective teaching-learning strategies for the instruction of the Korean phonetic system. This study has its significance in making such attempts.

• Journal of the Korean Society of Laryngology, Phoniatrics and Logopedics
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• v.10 no.2
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• pp.97-101
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• 1999

The nasalance score measured by Nasometer is a supplementary data for the perceptually rated nasality by a trained speech pathologist. Because the nasalance score varies with speech material, a valid and reliable material should be developed for evaluating it. The objectives of the present study were (1) to examine whether phonetic contexts affect the nasalace score and (2) to examine the reliability of both meaningless one-syllable words and meaningful sentences. This study analyzed nasalance score in 20 different phonetic contexts from 24 normal adults. The results showed (1) nasalance score increased as the percentage of nasal consonants and vowel /i/ increased, (2) the manner and the place of articulation in oral consonants did not influence the nasalance score, and (3) in nasalance score, correlation between sentences was found to be high, but correlation between syllables was not. These results may indicate that, when preparing the speech material for measuring the nasalance score, it is important to consider not only the percentage of nasal consonants but also that of vowel /i/ in the speech material. In addition, the sentence is more reliable material than meaningless one-syllable words.

• Phonetics and Speech Sciences
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• v.1 no.3
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• pp.19-28
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• 2009

This paper reports experimental findings about the duration feature of the acoustic components of English stops in Korean speakers' voicing perception. In our experiment, 35 participants discriminated between recorded stimuli and digitally transformed stimuli with different duration features from the original stimuli. 72 sets of paired stimuli are generated to test the effects of the duration feature in various phonetic contexts. The result of our experiment is a complicated cross-tabulation with 540 cells defined by five categorical independent variables plus one response variable. To find a meaningful generalization out of this complex frequency table, we ran logit log-linear regression analyses. Surprisingly, we have found that there is no single effect of the duration feature in all phonetic contexts on Korean speakers' perception of the voicing contrasts of English stops. Instead, the logit log-linear analyses reveal that there are interaction effects among phonetic contexts (=C), the places of articulation of stops (=P), and the voicing contrast (=V), and among duration (=T), phonetic contexts, and the places of articulation. To put it in mathematical terms, the distribution of the data can be explained by a simple log-linear equation, logF=${\mu}+{\lambda}CPV+{\lambda}TCP$.

• MALSORI
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• no.38
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• pp.25-39
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• 1999

Korean intonation has been investigated mainly from the point of view of impressionistic phonetics and phonology. The purpose of this paper is to investigate Korean intonation especially nuclear tones, from the point of view of experimental phonetics. Since what we hear is not always the always as what we see in fundamental frequency contours, acoustic characteristics of Korean nuclear times are first discussed Based m quantitative data similar nuclear times are compared and the relationship between the nuclear ton and sentence type is investigated The relationship between the nuclear tone and the speaker's attitude is also discussed.