• Applied Microscopy
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• v.30 no.1
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• pp.11-20
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• 2000

The morphological changes in normal and weathering hair shafts of the human scalp were investigated by using the transmission and scanning electron microscopes. The hair shaft composed of cuticular layer, cortex and medula. The surface of normal hairs are smooth and covered by imbricated cuticular scales. The cuticular layer consists of five to seven cuticle cells. These cells, which are flat and thin, measuring about $100{\mu}m$ long and $0.4{\mu}m$ thick, appears intercellular membrane complex in diameter 25 nm. The cortex composed of melanin granules and cornified cells, which multicomponent concentric microfibrils in diameter about 8 nm give rise to macrofibrils in diameter $0.5{\mu}m$ to $0.8{\mu}m$ encased in limiting membrane. The melanin granules are spherical shaped about $0.5{\mu}m$ in size and scattered between macrofibrils. The medulla in the normal hairs are $16{\mu}m$ in diameter centrally region of cortex. Normal hair shafts undergo progressive degenerative changes due to a variety of environmental insults. In the initial weathering process of hair, the cuticular scales became irregularly raised and broken, and then cuticle cells formed cytoplasmic vacuolation, following dissociated intercellular membrane complex, ultimately entirely lost and nuded cortex. Occasionally, transverse fissures were seen at hair shafts indicating that the hairs were deteriorated. Complete removal of the cuticular layer in the heavily damaged cortex portions appeared splitting of the cortical cell into its macrofibrils and scattering of melanin granules.

• The Korean Journal of Zoology
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• v.37 no.3
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• pp.452-465
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• 1994

미꾸리속의 미꾸리(Misgumus anguillicaudatus)와 미꾸라지(M. mizolepis)의 종내 및 종간 유전적 변이와 유전적 차이를 알아보고자 2종 15개집단과 대만산 Paramisgumus김늠bwanus 1개 집단을 대상으로 전기영동법의 의한 동위효소분석을 실시한 결과 각. ongui각caudotus 9개 집단의 평균 유전적 변이정도는 P=34.20%, Ho=0.099, He=0 114였고. M. mizolepgs 6개 집단은 평균 P=35.55%, Ho=0 141, He=0.148이었으며, p연abwonus는 P=45.9%, Ho=0.132. 연e=0.119로서 일반적인 담수어류에 비해 높은 변이를 나타내었다 종간 평균 유전적 근연치를 비교한 결과 M. aneuflISca udatuo와 M. mfzole부랍 사이는 5=0.467이었고. M. angu연흘audatus와 P. dabrvanus 사이는 5=0.475로 비교적 근연관계가 낮았으나 M. mizolep결와 P. dabwanuo 사이는 5=0.834로 매우 가까운 유연관계를 나타냈다 유전적 차이치를 토대로 M. ongu비상라udctus와 M. mfzolep결의 종분화 연대를 산출한 결과 이들은 약 350만년전에 분화된 것으로 추정되었다.

• Nuclear Medicine and Molecular Imaging
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• v.42 no.6
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• pp.435-443
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• 2008

Purpose: Gated myocardial perfusion SPECT provides not only myocardial perfusion status but also various functional parameters of left ventricle. We compared left ventricular ejection fraction, end-diastolic volume, LV mass by cardiac SPECT using Quantitative Gated SPECT (QGS), 4D-MSPECT software and standard 2D-echocardiography. Materials and Methods: One hundred fourteen patients (male 51, female 63; 29-85 years old, mean $61.3\;{\pm}\;13.3$ years old) with normal perfusion status on Tc-99m tetrofosmin gated myocardial perfusion SPECT were analyzed retrospectively. Ejection fraction (LVEF), End-diastolic volume (LVED), LV mass (LVM) were calculated using QGS, 4D-MSPECT, and LVEF, LVM using 2D-echocardiography. Statistical analysis including Bland-Altman plot was performed using $MedCalc^{(R)}$ (MedCalc software, Mariakerke, Belgium). Results: The correlation of LVEF between methods was good: 0.95/0.96 (stress/rest) between QGS and 4D-MSPECT, 0.79 between QGS and echocardiography, 0.79 between 4D-MSPECT and echocardiography (p<0.001). Using Bland-Altman plot, the 95% confidence interval of agreement between QGS and 4D-MSPECT ranged from -12.7% to 7.3% / from -12.2% to 6.5% (stress/rest). The agreement between QGS and echocardiography, 4D-MSPECT and echocardiography ranged from -17.4% to 24.0%, and -14.8% to 27.0% respectively. The correlation of LVM between methods was also good: 0.95 between QGS and 4D-MSPECT, 0.76 between QGS and echocardiography, 0.73 between 4D-MSPECT and echocardiography (p<0.001). The 95% confidence interval of agreement between QGS and 4D-MSPECT ranged from -33.8g to 14.1g (stress/rest), The 95% confidence interval of agreement between QGS and echocardiography, 4D-MSPECT and echocardiography ranged from -148.7 g to 21.8. g, and -142.8 g to 35.5 g, respectively. Conclusion: There was a good correlation for LVEF, LVEO, LVM among methods (QGS, 4D-MSPECT, echocardiography), but the variance between methods was big. Therefore, the functional parameters by each method cannot be used interchangeably.

• The Journal of the Acoustical Society of Korea
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• v.23 no.5
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• pp.340-352
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• 2004

Acoustic streaming induced by the microscopic longitudinal ultrasonic vibration at 28.5 ㎑ is visualized between the quiescent glass plate and ultrasonic vibrator by particle imaging velocimetry(PIV) using laser. To investigate the augmentation of air flow velocity of acoustic streaming. the velocity variations of air streaming between the stationary plate and ultrasonic vibrator are measured in real-time. It is experimentally investigated that the magnitude of the acoustic streaming dependent upon the gap between the ultrasonic vibrator and stationary p1ate results in the variations of the average velocity fields as a outcome of the bulk air flow caused by the ultrasonic vibration. In addition. maximum acoustic streaming velocity exists at resonant gap. 18mm that is one of the resonant gaps (H=18, 24, 30, 36㎜) at which resonance occurs. The variation of the local maximum turbulent intensity with axial direction appear to reveal the value of 8%∼70% dependent upon the gap between the quiescent glass plate and ultrasonic vibrator. Shearstress is also maximized at the center region of the vibrator and the vorticity is also maximum and minimum in the neighborhood of the center of the vibrator at which the local maximum turbulent intensity and shear stress exist.

• Proceeding of EDISON Challenge
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• 2016.03a
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• pp.622-624
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• 2016

교량의 케이블이나 송전선같은 원형 구조물들은 유동의 불안정성에 의해 물체 후방에 Vortex가 발생한다. 이렇게 발생한 Vortex는 구조물에 진동과 소음을 발생시키게 된다. 본 연구에서는 이러한 원형 구조물들의 배열에 따른 해석을 진행하였다. 같은 크기의 두 원형 실린더를 주 유동 방향으로 정렬시킨 배열을 EDISON 전산열유체 시스템을 이용하여 해석하였다. 두 원형 실린더의 중심의 거리를 1.5 D부터 5 D까지 변화시켜가며 거리에 따른 각 실린더의 Drag coefficient에 초점을 맞추어 연구를 진행하였다. 두 원형 실린더 사이의 거리가 감소할수록 후류 쪽에 위치한 실린더의 Drag coefficient의 값이 감소하는 양상을 보였다.

• Journal of Digital Convergence
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• v.18 no.2
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• pp.377-383
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• 2020

Digital signage is constantly being researched as new digital video platform to replace existing signage market. Traditionally, It conveys various information combining still images with text. Nowadays, it is rapidly exchanging to multi digital platform by high specificaton system, improvement of internet speed and advancement of video and audio compression technology with HTML5 technology. Not only a single wide-screen display but also the combination and adjustment of screens with setop box, OLED, media facades, and lase beam projectors are transformed into various forms to enable creative and diverse attempts for graphic designers. This study focuses on the application of motion graphics in rapidly evolving future platform - digital signage, and looking forward to help digital video content creator, researchers, and motion graphic designers.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.16 no.5
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• pp.3148-3154
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• 2015

The purpose of this study was to examine the usefulness of psychodrama as a self-development program for university students by applying it to D university student during 10 weeks. The study results were produced by quantitative and qualitative analyses on the data. At first, according to the quantitative analyses result, the identities of the participated students did not show significant differences between pre and post program participation, statistically. But according to the qualitative analyses on the participants experience reports, which were written by them at each session, the participants had experienced the 'fresh impulse' and the 'enlightenment through the body' at the introduction stage. And, they had experienced the 'whirlwind for the development' and the 'developments through suffering and bearing' at the actualization stage. Eventually, these results proved that psychodrama was useful for the university students to develop their inner side, by bearing and overcoming the physically mentally chaotic experiences from it.

• Korean Journal of Plant Tissue Culture
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• v.22 no.4
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• pp.217-221
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• 1995

This experiment was carried out to determine the effects of genotyes (cultivars) and kinds of cytokinins and concentrations on shoot multiplication of roses (Rosa hybrida) by nodal culture. The results from this study were summarized as follows. Shoot multiplication was significantly affected by genotypes. Most shoots were produced from 'Carl Red 'rather than two other cultivars, 'Golden Emblem' and 'Tineke'. Among 3 cytokinins, BA was more significantly effective for multiplication than two other cytokinins, 2iP and kinetin. However subsequent shoot growth after multiplication was more enhanced by 2iP and kinetin rather than BA. An optimal concentration of cytokinin for shoot multiplication was 1 mg/L in this study but BA at 1-5 mg/L was considered optimal for multiplication ratio itself. Subsequent shoot growth was significantly inhibited by increases in cytokinin concentrations, regardless of kinds of cytokinin.

• The Journal of the Acoustical Society of Korea
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• v.41 no.1
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• pp.9-15
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• 2022

In order to overcome the limitation of conventional nanoparticle dispersion methods such as sonicator or homogenizer, a filtration method using an ultrasonic atomization effect and cyclones was proposed in this study. A 0.5 wt% suspension was made with Al₂O₃ powder with an average diameter of 250 nm. The suspension was filtered by the proposed method after pre-dispersing using a sonicator and a homogenizer, respectively. As the result, in the case of the suspension after pre-dispersing with a sonicator, the particle size distribution of the filtered suspension started showing up a single normal distribution indicating the mode of the average diameter only after the 3rd cyclone process. On the other hand, in the case of the suspension with the homogenizer pre-dispersion, similar results appeared from the 2nd cyclone process. Filtration of various types of nanoparticles is expected to be possible by adjusting ultrasonic atomization frequency and manipulating the design of the cyclone.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.3 no.2
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• pp.117-119
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• 1970

A goby Synechogobius hasta (TEMMINCK et SCHLEGEL) was studied on the length-weight relation-ship, and the fish were sampled from the closed tributary and the lower part of the Naktong River, near Pusan, during the period from November of 1967 to December of 1968. The data for this study were taken from 1,050 fish. The relationships between the body length (X) and body weight (Y) are indicated as follows: 7.5cm to 32.5cm: $Y=0.09863X^{2.17926}$ 7.5cm to 19.5cm: $Y=0.04995X^{2.472l6}$ 28.5Cm to 32.5Cm: $Y=0.0004127X^{3.67265}$ The normal relative growth was not found in fish between 20.5cm and 27.5cm in body length, because of the maturity of gonads and spawning.