• 한국표면공학회:학술대회논문집
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• 한국표면공학회 2007년도 춘계학술발표회 초록집
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• pp.5-6
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• 2007

반투명 전도성 음극 (semi-transparent conducting cathode)인 Ba (x nm)/Au (20 nm)/ITO (100 nm)을 이용하여 전면발광 유기전계 발광 소자 (top-emitting organic light-emitting didodes, TEOLEDs)를 제작했다. Ba과 bis(8-quinolinolato)aluminum (III) ($Alq_3$) 계면의 전자구조는 엑스선 광전자 분광법 (X-ray photoelectron spectroscopy, XPS), 자외선 광전자 분광법 (ultraviolet photoelectron spectroscopy, UPS) 및 가까운 끝머리 엑스선 흡수 미세구조 (near-edge x-ray absorption fine structure, NEXAFS) 스펙트럼의 광 방출 특성을 통하여 조사되었다. $Alq_3$/Ba 계면 특성에 있어서 XPS와 NEXAFS 특성에 의하면, $Alq_3$ (10.0 nm) 위에 Ba이 연속적으로 증착됨에 따라 Ba으로부터 $Alq_3$로의 전자전달 (electron charge transfer) 특성은 꾸준희 증가된다. 그러나 Ba의 두께가 1.0 nm 이상 초과되면 Ba의 전자전달에 기인한 반응성때문에 $Alq_3$의 분자구조가 해리된다. 한편, 제작된 TEOLEDE의 전류-전압-휘도 곡선의 경우에서도 바륨의 증착 두께가 1.0 nm일 때 가장 우수한 구동특성을 나타냈다.

• 한국분말재료학회지
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• 제26권1호
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• pp.45-48
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• 2019

Quantum dots (QDs) are an attractive material for application in solar energy conversion devices because of their unique properties including facile band-gap tuning, a high-absorption coefficient, low-cost processing, and the potential multiple exciton generation effect. Recently, highly efficient quantum dot-sensitized solar cells (QDSCs) have been developed based on CdSe, PbS, CdS, and Cu-In-Se QDs. However, for the commercialization and wide application of these QDSCs, replacing the conventional rigid glass substrates with flexible substrates is required. Here, we demonstrate flexible CISe QDSCs based on vertically aligned $TiO_2$ nanotube (NT) electrodes. The highly uniform $TiO_2$ NT electrodes are prepared by two-step anodic oxidation. Using these flexible photoanodes and semi-transparent Pt counter electrodes, we fabricate the QDSCs and examine their photovoltaic properties. In particular, photovoltaic performances are optimized by controlling the nanostructure of $TiO_2$ NT electrodes.

• 대한기계학회논문집B
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• 제20권7호
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• pp.2289-2297
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• 1996

Flows in the combustion chamber near the spark plug are measured using LDv.A single cylinder DOHC S.I. engine of compression ratio 9.5:1 with a transparent quartz window piston is used. Combustion chamber shape is semi-wedge type. Measured data are analyzed using the ensemble averaged analysis and the cycle resolved analysis which uses FFT Filtering. Turbulent intensity and mean velocity are studied in the main flow direction and the normal to main flow direction as a function of engine speeds. The results shows that the turbulent intensity obtained by the ensemble averaged analysis is greater than that calculated by the cycle resolved analysis. Especially, the ensemble averaged analysis shows increase in turbulence at the end of compression stroke although the cycle resolved analysis shows increase only in the cycle-by-cycle variation with no noticeable increase in turbulence. The mean velocity in the main flow direction increase as engine speed increase. But the mean velocity normal to the main flow does not show such increase. Turbulent intensity in both direction increase in proportion to engine speeds. The magnitude of turbulent intensity is about 0.3 ~ 0.4 times the mean piston speeds at the end of the compression stroke.

• 대한예방한의학회지
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• 제6권1호
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• pp.162-166
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• 2002

혈관내 봉한관을 관찰하는 방법을 개발하였다. 10% 포도당액을 대퇴정맥에 주입하여 봉한관을 굵고 강하게 만듦으로써, 혈관 절개후 쉽게 관찰할 수 있게 한 것이 핵심 기법이다. 봉한이론과 일치한 결과를 보였다. 봉한관은 반투명의 부드럽고 탄력 있는 실과 같으며, $10{\mu}m$ 정도의 작은 관의 다발로 구성되어 있다.

• The Plant Pathology Journal
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• 제24권4호
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• pp.407-416
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• 2008

Studies were conducted to determine the effects of temperature, solute potential and carbon source on the mycelial growth, sclerotia development, and apothecium production of an isolate of Sclerotinia sclerotiorum. Mycelial growth rate was greatest at $25^{\circ}C$ on potato dextrose agar (PDA) medium amended with up to 2% NaCl (${\psi}s{\leq}1.91\;MPa$) and thereafter, growth rate declined. The least number of sclerotia were produced at $20^{\circ}C$on both PDA and malt extract agar (MEA) amended with 8% NaCl (${\psi}s=6.62\;MPa$). With increasing temperature and decreasing solute potential the number and size of sclerotia were significantly reduced. The combined effect of temperature, solute potential and carbon source on sclerotia production were highly significant and had an impact on the development of the rind layer cells of sclerotia. These cells lacked a transparent cell wall which was surrounded by a compact melanized layer, and some of these cells appeared to be devoid of cell contents or were totally vacuolated. The survival of the sclerotia with increase in salinity and temperature appeared to affect melanization and the nature of the rind cells. The observations of this study re-enforces the need for an integrated disease management to control S. sclerotiorum.

• 한국정보과학회논문지:소프트웨어및응용
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• 제35권12호
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• pp.753-763
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• 2008

UCC(User Created Contents)의 급격한 증가에 따라 저작권 문제도 크게 대두되고 있다. 자동 로고 인식은 이러한 저작권 문제를 해결하기 위한 효율적인 방법이다. 로고는 다양한 특징을 가지고 있고, 이러한 특징들은 로고 검출과 인식을 어렵게 한다. 특히, 비디오 내에 빈번한 로고 전이가 일어날 경우, 정확한 로고 인식과 로고 기반 분할이 어렵다. 따라서 본 논문에서는 디지털 비디오에서 로고 인식을 위한 정확한 전이 검출 방법과 다양한 로고 타입 인식 방법을 제안한다. 제안한 로고 검출과 로고에 따른 비디오 분할을 이용하여 다양한 비디오에 대한 좋은 실험 결과를 얻을 수 있었다.

• 한국태양에너지학회:학술대회논문집
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• 한국태양에너지학회 2008년도 추계학술발표대회 논문집
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• pp.57-62
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• 2008

Building Integrated PV(BIPV) is one of the best fascinating PV application technologies. To apply PV module in building, various factors should be reflected such as installation position, shading, temperature, and so on. Especially the installation condition should be considered, for the generation performance of PV module is changed or the generation loss is appeared according to installation position, method, and etc. This study investigates variation of electrical characteristics of a PV module according to the change of irradiance and temperature. From this experimental study, we confirmed that the irradiance, the temperature variation and the generation performance of a PV module were appeared differently according seasonal variation. Actually the PV module installed in building facade showed high-generation performance in winter.

• 한국방송∙미디어공학회:학술대회논문집
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• 한국방송공학회 2009년도 IWAIT
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• pp.664-667
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• 2009

There is strong demand to create wearable PC systems that can support the user outdoors. When we are outdoors, our movement makes it impossible to use traditional input devices such as keyboards and mice. We propose a hand gesture interface based on image processing to operate wearable PCs. The semi-transparent PC screen is displayed on the head mount display (HMD), and the user makes hand gestures to select icons on the screen. The user's hand is extracted from the images captured by a color camera mounted above the HMD. Since skin color can vary widely due to outdoor lighting effects, a key problem is accurately discrimination the hand from the background. The proposed method does not assume any fixed skin color space. First, the image is divided into blocks and blocks with similar average color are linked. Contiguous regions are then subjected to hand recognition. Blocks on the edges of the hand region are subdivided for more accurate finger discrimination. A change in hand shape is recognized as hand movement. Our current input interface associates a hand grasp with a mouse click. Tests on a prototype system confirm that the proposed method recognizes hand gestures accurately at high speed. We intend to develop a wider range of recognizable gestures.

• 대한기계학회논문집B
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• 제22권3호
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• pp.399-407
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• 1998

The infrared reflection coatings with pigment can be used to protect the surfaces of combustible materials exposed to fire. To obtain high reflectivities in the infrared range (0.5-10.mu.m) important to fire, several dielectric pigments, such as titanium dioxide, iron oxide, and silicon, can be synthesized to polymer coatings. The theoretical analysis shows that the coating design with particles diameter in the 1.5 to 2.5.mu.m range and volume fraction in the 0.1 to 0.2 range is estimated to be optimal. In the analysis of the radiation, the dependent scattering, absorption by polymeric binder, and the internal interface reflection are considered. In addition, the temperature distribution in the semi-transparent coating layer and an opaque substrate (PMMA) is also presented.

• JSTS:Journal of Semiconductor Technology and Science
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• 제11권1호
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• pp.40-50
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• 2011

A two-dimensional (2D) analytical model for the potential distribution and threshold voltage of short-channel ion-implanted GaAs MESFETs operating in the sub-threshold regime has been presented. A double-integrable Gaussian-like function has been assumed as the doping distribution profile in the vertical direction of the channel. The Schottky gate has been assumed to be semi-transparent through which optical radiation is coupled into the device. The 2D potential distribution in the channel of the short-channel device has been obtained by solving the 2D Poisson's equation by using suitable boundary conditions. The effects of excess carrier generation due to the incident optical radiation in channel region have been included in the Poisson's equation to study the optical effects on the device. The potential function has been utilized to model the threshold voltage of the device under dark and illuminated conditions. The proposed model has been verified by comparing the theoretically predicted results with simulated data obtained by using the commercially available $ATLAS^{TM}$ 2D device simulator.