• The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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• v.34 no.3
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• pp.80-91
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• 2021

Objective : The purpose of this study is to discriminate the vestibular schwannoma misdiagnosed as Idiopathic Sudden Sensorineural Hearing Loss. Methods : A 46-year-old female patient who was suffering left sudden sensorineural hearing loss(SSNHL), visited after diagnosed as Idiopathic SSNHL by previous hospital. For diagnosing the vestibular schwannoma, we conducted the Puretone audiometry, auditory brainstem response threshold test and magnetic resonance imaging(MRI) for temporal bone with enhancement. Result : Auditory Brainstem Response threshold test was abnormal and in enhanced MRI, the vestibular schwannoma in left side was detected. The patient was discharged from the hospital for tertiary hospital care. Conclusions : When the patient with SSNHL visits a hospital even if after diagnosed as Idiopathic SSNHL by previous hospital, a doctor should keep in mind the possibility of vestibular schwannoma.

• The Journal of the Acoustical Society of Korea
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• v.28 no.6
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• pp.526-533
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• 2009

This paper proposes a formant synthesis method of Haegeum sounds using cepstral envelope for spectral modeling. Spectral modeling synthesis (SMS) is a technique that models time-varying spectra as a combination of sinusoids (the "deterministic" part), and a time-varying filtered noise component (the "stochastic" part). SMS is appropriate for synthesizing sounds of string and wind instruments whose harmonics are evenly distributed over whole frequency band. Formants extracted from cepstral envelope are parameterized for synthesis of sinusoids. A resonator by Impulse Invariant Transform (IIT) is applied to synthesize sinusoids and the results are bandpass filtered to adjust magnitude. The noise is calculated by first generating the sinusoids with formant synthesis, subtracting them from the original sound, and then removing some harmonics remained. Linear interpolation is used to model noise. The synthesized sounds are made by summing sinusoids, which are shown to be similar to the original Haegeum sounds.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2005.11b
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• pp.129-133
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• 2005

Vibration transmitted through rolling tire is a major source of road noise in vehicle interior noise on the range of low frequency.($0{\sim}500Hz$) Among various road noises, tire cavity noise has very peak on $200{\sim}250Hz$. And generally it is generated by cavity resonance of tire. In this paper, tire cut-sample is used to calculate the tire cavity frequency. Cavity resonance frequency of tire is measured through vertical/tangential forces at load cell of axle using drum cleat impact. This method is useful to find cavity peak because measured forces do not have complex peaks. And changing the test conditions (air inflation, loads), tire cavity resonance characteristics are identified. Finally, vehicle interior noise is measured as tire/vehicle are changing. As difference of tire vertical force is bigger, interior noise level is higher at cavity frequency. Also we can assume that vehicle sensitivity is important factor at tire cavity noise.

• Investigative Magnetic Resonance Imaging
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• v.18 no.1
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• pp.25-33
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• 2014

Purpose : To investigate whether quantitative parameters derived from Diffusion-weighted magnetic resonance imaging (DW-MRI) correlate with those of Dynamic contrast-enhanced MRI (DCE-MRI). Materials and Methods: Thirteen patients with pathologically or clinically proven bony metastasis who had undergone MRI prior to treatment were included. The voxel size was $1.367{\times}1.367{\times}5mm$. A dominant tumor was selected and the apparent diffusion coefficient (ADC) value and DCE-MRI parameters were obtained by matching voxels. DCE-MRI data were analyzed yielding estimates of $K^{trans}$ (volume transfer constant) and $v_e$. (extravascular extracellular volume fraction). Statistical analysis of ADC, $K^{trans}$, and $v_e$ value was conducted using Pearson correlation analyses. Results: Fifteen lesions in pelvic bones were evaluated. Of these, 11 showed a statistically significant correlation (P<0.05) between ADC and $K^{trans}$. The ADC and $K^{trans}$ were inversely related in 7 lesions and positively related in 4 lesions. This did not depend on the primary cancer or site of metastasis. The ADC and $v_e$ of 9 lesions correlated significantly. Of these, 4 lesions were inversely related and 5 lesions were positively related. Conclusion: Unlike our theoretic hypothesis, there was no consistent correlation between ADC values and $K^{trans}$ or between ADC values and $v_e$ in metastatic bone tumors.

• Korean Journal of Cognitive Science
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• v.21 no.1
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• pp.77-93
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• 2010

The aim of this study was to identify neural correlates underlying the detection of faux pas, a test of theory of mind (ToM), in Korean healthy adults. Using functional magnetic resonance imaging, we compared the brain activities associated with faux pas stories and the activities associated with control stories. Faux pas stories compared with the control stories produced activations bilaterally in the superior frontal gyrus (BA 9) and in the precuneus (BA 7). The left medial frontal gyrus (BA 9), the left superior temporal gyrus (BA 38), the left inferior temporal gyrus (BA 20) and the right inferior parietal lobule (BA 40), the right postcentral gyrus (BA 1), the right lingual gyrus (BA 18), the right transverse temporal gyrus (BA 41) were also activated. The orbitofrontal cortex and the amygdala were not found to be involved in the detection of faux pas. This result suggests that brain activations associated with ToM are dependent on the type of mental state drawn by the task.

• Journal of the Korean Chemical Society
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• v.21 no.3
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• pp.171-179
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• 1977

Proton magnetic resonance spectra of five glycine-containing dipeptides glycyl-L-valine, L-valyl-glycine, glycyl-DL-alanine, glycyl-DL-serine and glycyl-L-aspartic acid in $D_2O$ were investigated as a function of pH at room temperature. From the analysis of the spectra, it was found that the chemical shift of the $C_{\alpha}H,\;C_{\beta}H\;and\;C_rH$protons varies with pH as a one-step titration curve, and that the spin-spin coupling constant remains almost unchanged. Two distinct values of the chemical shift for $C_{\alpha}H,\;C_{\beta}H\;or\;C_rH$protons of constituent amino acids in dipeptide solutions indicate the existence of two magnetically non-equivalent sites in solution. From this study, the structures of the five dipeptides have been confirmed by proton magnetic resonance spectra and it has been suggested that the structural change, conformation and sequence determination can be explored for oligopeptides by an analysis of proton magnetic resonance spectra.

• Cross-Cultural Studies
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• v.39
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• pp.381-406
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• 2015

Russian nasal consonants / m /, / n / have a feature value not only [+consonant] in common with obstruents, but also [+sonorant] in common with vowels. Nasal / m /(bi-labial) and / n /(dental) have the same place of articulation but different manner of articulation. The feature value of / m / is [+cons, +son, +nas, +ant, -cor, -high, -low, -back, -cont, -del, rel, -strid, +voic], and that of / n / is [+cons, +son, +nas, +ant, +cor, -high, -low, -back, -cont, -del, rel, -strid, + voic]. There is a difference in feature [cor] value of / m / and / n /. In this study it is confirmed that it is a fact that the Russian nasal consonants behave differently from the other consonants in each phonological phenomenon due to their phonological characteristics. The preceding voiced obstruent is changed to an unvoiced one in a process where the last voiceless obstruent in the consonant cluster ' voiced obstruent + nasal /m/ + voiceless obstruent' skips the nasal consonant and spreads its feature value to the preceding voiced obstruent transparently because of the feature [+sonorant] of the nasal consonant. The coronal nasal /n/ participates in a palatalization with the following palatal actively and palatalize preceding plain consonants passively because of markedness hierarchy such as 'Velar > Labial > Coronal'. But the labial nasal /m/ is palatalized with the following velar palatal actively and participates in a palatalization with the following coronal palatal passively. This result helps us confirm the phonological difference of /m/ and /n/ in a palatalization. When the a final consonant is nasal, the unvoicing phenomenon of a final consonant doesn't occur. In such a case as cluster 'obstruent + nasal' the feature value [voiced] of the preceding obstruent doesn't change, but the following nasal can assimilate into the preceding obstruent. When continuing the same nasals / -nn- / in a consonant cluster, the feature value [+cont] of a weak position leads the preceding nasal / n / to be changed into [-cont] / l /. Through the analysis of the frequency of occurrences of consonants in syllabic onsets and codas that should observe the 'Sonority Sequence Principle', the sonority hierarchy of nasal consonants has been confirmed. In a diachronic perspective following nasal / m /, / n / there is a loss of the preceding labial stop and dental stop. But in clusters with the velar stop+nasal, the two-component cluster has been kept phonetically intact.

• Journal of the Korea Computer Industry Society
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• v.2 no.4
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• pp.471-480
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• 2001

In this thesis, we perform the experiment of speaker recognition by identifying vowels in the pronunciation of each speaker using Adaptive Resource Theory 2(ART2) model. The 5 adult males and 5 adult females pronounce from 0 to 9 digits. We extract the vowels from the pronunciation of each speaker first, we are extracted characteristic coefficient through a pitch detection algorithm, a LPC analysis, and a LPC cepstral analysis to generate an input pattern of ART2. The experimental results showed that pitch coefficients are somewhat more enhanced than LPC or LPC cepstral coefficient.

• Phonetics and Speech Sciences
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• v.5 no.4
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• pp.145-155
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• 2013

This study investigated the articulatory characteristics of Korean singleton and geminate sonorants in the word-medial position, effects of the duration of the sonorant consonant and the preceding vowel on perception, and the difference between native Korean speakers and foreign learners of Korean in perceiving the singleton and geminate consonant contrast. The Korean sonorant consonants(/m, n, l/) are examined from the VCCV, VCV sequences through speech production and perception experiments. The results suggest that the duration of the sonorant consonant is the most important factor for native Korean speakers to recognize whether sonorants are overlapped, and the duration of preceding vowel and other factors affect the recognition of singleton/geminate consonant contrast if the duration is not obvious. A perception experiment showed Chinese Korean language learners did not clearly distinguish singleton consonants from geminate consonants. The results of this study provide basic data for recognition of singleton/geminate consonant contrast in word-medial of Korean language, and can be utilized for teaching Korean pronunciation as a foreign language.

• Proceedings of the KSLP Conference
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• 2003.11a
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• pp.146-146
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• 2003

연인두 폐쇄 부전으로 보상조음이 있을 때, 말 명료도를 저하시킬 뿐 아니라 실제의 연인두 기능이 과소평가 될 수 있으므로 이에 대한 감별 및 언어치료가 필수적이다. 본 연구에서는 연인두 폐쇄 부전 환자들에서 보상조음의 출현율을 알아보고 어떤 음소들이 영향을 받는지 살펴보고자 하였다. 또한 연령과 과비성의 정도에 따른 차이도 살펴보았다. 1998년 3월부터 2003년 6월까지 삼성서울병원에서 연인두 폐쇄 부전으로 진단 받고 언어치료를 받지 않았거나 언어치료 경험은 있지만 일반화되지 않고 중단된 환자 105명의 조음 및 공명 평가 자료를 분석하였다. 연령은 평균 11.3세(2.1세부터 63세)였고 7세 이하의 아동집단이 65명, 성인집단이 40명이었다. 조음은 구강압력자음인 파열음, 마찰음, 파찰음에서의 보상조음의 유무 및 종류를 분석하였다. 과비성의 정도는 경도, 중도, 심도로 평가하였다. (중략)