• 한국정보통신학회논문지
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• 제8권6호
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• pp.1182-1187
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• 2004

본 논문에서는 실시간으로 눈과 눈썹주위의 특징을 추적하는 새로운 알고리즘을 제안하고자 한다. 제안된 알고리즘은 적외선 LED와 적외선카메라로 밝은 동공 효과를 만들어 동공을 추적 한 후, 템플릿은 얼굴 특징을 매개변수화 하기 위해, 동공 좌표는 각각의 프레임에서 눈과 눈썹 영상을 추출하기 위하여 사용한다. 또한, 템플릿 변수는 표본 영상을 가지고 학습하는 과정에서 구성한 PCA기저를 이용하여 추출된 영상을 PCA 분석하여 구한다. 제안된 시스템은 초당 30 프레임의 영상에서 초기 설정 및 교정 작업 없이 머리 움직임이 많거나 폐색이 있는 경우에도 견실하게 동작하였다.

• 반도체디스플레이기술학회지
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• 제18권3호
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• pp.100-104
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• 2019

We have investigated the feasibility of fabricating fine stripes using needle coating for potential applications in solution-processed organic light-emitting diodes (OLEDs). To this end, we have employed an aqueous poly(3,4-ethylenedioxythiophene):poly(4-styrenesulfonate) (PEDOT:PSS) solution that has been widely used as a hole injection layer (HIL) of OLEDs and performed needle coatings by varying the process parameters such as the coating gap and coating speed. As expected, the stripe width is reduced with increasing coating speed. However, the central thickness of the stripe is rather increased as the coating speed increases, which is different from other coating processes such as slot-die and blade coatings. It is due to the fact that the meniscus formed between the needle tip and the substrate varies depending sensitively on the coating speed. It is also found that the stripe width and thickness are reduced with increasing coating gap. To demonstrate its applicability to OLEDs, we have fabricated a red OLED stripe and obtained light emission with the width of about 90㎛.

• 천문학회보
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• 제37권2호
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• pp.205.2-205.2
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• 2012

MIRIS (Multipurpose Infra-Red Imaging System), the main payload of STSAT-3 (Science and Technology Satellite-3), is the first Korean Infrared Space Telescope developed by KASI (Korea Astronomy and Space Science Institute). The FM (fight model) of MIRIS has been recently completed, and various performance tests have been made to measure system parameters such as readout noise, system gain, linearity, and dark current. The MIRIS FM has been integrated to the satellite system for the environment tests scheduled in September 2012. The MIRIS is expected to be launched in November 2012.

• 천문학회보
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• 제37권2호
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• pp.84.2-84.2
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• 2012

We present wide-field multiband photometry of globular cluster (GC) systems toward the central region of the Fornax cluster of galaxies, including NGC 1399, NGC 1404, and NGC 1387. Observation was carried out through four optical passbands (U, B, V, and I) with the Mosaic II CCD imager mounted on the 4-m Blanco telescope at Cerro Tololo Inter-American Observatory (CTIO). This marks one of the widest U-band photometric studies on GC systems. GC candidates are selected among point sources based on their two color diagrams together with a magnitude cut. We investigate the radial variation of color distributions for the GC systems, focusing on the fundamental parameters that characterize bimodal distributions; the number ratio between blue and red GCs, the mean colors of the groups, and their color dispersions. We discuss the implication of our result regarding the origin of GC color bimodality.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2009년도 춘계학술대회 논문집
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• pp.254-259
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• 2009

In this study, Simplified Method for the Atmospheric Correction (SMAC) radiative transfer model (RTM) used to retrieve surface reflectance from MODIS Top Of Atmosphere (TOA) reflectance (MOD02). SMAC code provides coefficients which were previously yielded by Second Simulation of the Satellite Signal in the Solar Spectrum (6S) for each satellite sensor. We conducted error analysis of SMAC RTM using MOD02 over comparison with MODIS surface reflectance (MOD09) which was provided from 6S. It showed that low accuracy values such as, $R^2$ : 0.6196, Root Means Square Error (RMSE) : 0.00031, bias : - 0.0859. Thus sensitivity analysis of input parameters and coefficients was conducted to searching error sources. Coefficients about $\tau_p$ (average AOD) are more influence than any other coefficients of $\tau_{a550}$ (Aerosol Optical Depth at 550nm) from sensitivity test. Calibrated coefficients of $\tau_p$ from regression analysis were used to surface reflectance which showed that improve accuracy of surface reflectance ($R^2$ : 0.827, RMSE : 0.00672, bias : - 0.000762).

• 천문학회보
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• 제36권1호
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• pp.63.2-63.2
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• 2011

We present a photometric study of star clusters in three nearby barred spiral galaxies NGC 1300, NGC 1672 and NGC 6217. We use the Hubble Heritage CCD images taken with Advanced Camera for Surveys (ACS) of Hubble Space Telescope (HST) in several filters. We have selected hundreds of star clusters with V $\leq$ 24 mag in each galaxy, based on the morphological parameters and visual inspection. Most of the blue star clusters with B-V $\leq$ 0.5 are strongly concentrated in spiral arms. A significant fraction of these star clusters are distributed in ansae (the joint between spiral arms and bar structure). Some of the blue star clusters are also found in the nuclear starburst region, especially in NGC 1672. A small number of star clusters are found in the bar region. In contrast, the red star clusters with B-V < 0.5 are relatively uniformly located over the entire field of galaxy, and show some central concentration around the bulge. We discuss the physical properties of these star clusters with the expected results from simulations.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2005년도 추계학술대회 논문집
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• pp.535-538
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• 2005

The purpose of this work is to study a process organization on space cognition by visio-auditory stimulation. We develop the system of visuo-auditory stimulation and Humans responses measurement to observe the relationship between the sensory and the motor system fur the localization of visual and auditory target direction in the space. The experiments is performed in a soundproof chamber, 2163 red, green and yellow LED(Luminescent Diode, Brightness: $20cd/m^2$ 1 degree apart each other)arrayed in front of half-circle panel were used and 57 Speaker(5 degree apart each other) arrayed in the hidden of half-circle panel. Physiological parameters such as EOG (Electro-Oculography), head movement and their synergic control are measured by BIOPAC system and Optotrak Certus. This result shows that the response latency time of the perception motion in the center is laster than the periphery of panel. These results can be used in the study of characterizing the spatial cognition.

• Membrane and Water Treatment
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• 제9권2호
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• pp.87-94
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• 2018

The interactions of water soluble polymers with dye are studied by ultrafiltration using a molecular weight cut off of 10 KDa regenerated cellulose ultrafiltration membrane. Two water-soluble polymers, namely Poly (Sodium-4 Styrenesulfonate) (PSS) and Poly (Vinyl Alcohol) (PVA) were selected for this study. The effects of process parameters, such as, polyelectrolyte concentrations, transmembrane pressure, ionic strength and pH of solution on dye retention and permeation flux were examined. PSS enhanced ultrafiltration achieved dye retention as high as 99% as a result of complexation between polyanion containing aromatic groups and cationic dye. This result was confirmed by the red shift. The retention of dye decreases as the salt concentration increases, a high retention was obtained at pH above 4. However, in case of PVA, relatively low retention (50%) was observed. Ionic strength and pH has no significant effect on the removal of MB. The permeate flux depended slightly on polyelectrolytes concentrations, transmembrane pressure, salt concentration and pH.

• Bulletin of the Korean Chemical Society
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• 제6권2호
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• pp.74-79
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• 1985

The stabilities of the charge transfer complexes of pentamethyl benzene with iodine in n-hexane have been investigated by UV-spectrophotometric measurements at 25, 40 and 60$^{\circ}C$ up to 1600 bars. The equilibrium constant of the complex formation was increased with pressure while being decreased with temperature raising. Changes of volume, enthalpy, free energy and entropy for the formation of the complexes were obtained from the equilibrium constants. The red-shift at higher pressure, the blue-shift at higher temperature, and the relation between pressure and oscillator strength have been discussed by means of thermodynamic functions. In comparison with the results in the previous studies, the absolute values of ${\Delta}$V at each temperature were increased with the number of methyl groups of polymethyl benzene. However, it can be seen that both ${\Delta}$H and ${\Delta}$S show extreme behaviors in durene near atmospheric pressure but they are negatively increased with the number of methyl groups near 1600 bar. This order of the thermodynamic parameters may be a measure of the relative basicities of polymethyl benzenes toward iodine under each pressure, and these phenomena are explained in terms of a positive inductive effect and a steric hindrance effect of the polymethyl benzene molecule.

• Clinical and Experimental Pediatrics
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• 제64권1호
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• pp.31-36
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• 2021

Background: The diagnosis of esophageal varices (EV) is based on the findings of esophagogastroduodenoscopy (EGD), biopsy, and serum markers. Thus, noninvasive cost-effective tests through which high-risk EV children can be diagnosed are needed. Purpose: This cross-sectional study aimed to identify the noninvasive markers for EV in children with liver cirrhosis. Methods: A total of 98 children with liver cirrhosis were evaluated in this study. The spleen size, platelet count, serum albumin, liver function test results, and risk scores were evaluated prior to endoscopy. The endoscopic investigations aimed to identify the presence of EV and red signs, and determine varices sizes. Results: Endoscopy revealed varices in 43 subjects (43.9%). The spleen size, platelet count, international normalized ratio, aspartate aminotransferase to platelet ratio index (APRI), platelet count to spleen size ratio, and risk score differed significantly between patients with and without EV on univariate analysis; however, the logistic regression analysis showed no differences, indicating that none of these parameters were independently associated with the presence of EV. Conclusion: Platelet count, risk score, platelet count to spleen size, and APRI can be useful tools for the identification of high-risk patients with EV and might reduce the need for invasive methods like EGD.