• 한국우주과학회:학술대회논문집(한국우주과학회보)
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• 한국우주과학회 1992년도 한국우주과학회보 제1권1호
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• pp.18-18
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• 1992

Spectroscopic CCD observations were carried out for V 1119 Cygni and the spectrum inthe visual region is analysed relative to the SLln with a line-blanketed convective modelatmosphere. Adopted atmospheric parameters are : an effective temperature ( Teff) =7000 K, a surface gravity log g = 3.4. Although our result is dependent onmicroturbulent velocity and damping constant, it was found that Mg in V1719 Cygni isnearly solar, or underabundant by 0.2 to 0.3 dex according to the analysis of5172.684A Mg I line which is relatively free from blending. This is inconsistentwith the previous photometric result wh(:re V1719 Cygni was known as anabnormally metal rich variable.

• 한국농공학회논문집
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• 제58권1호
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• pp.91-97
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• 2016

The objective of this study was to classify between radish and Chinese cabbage in autumn using hyperspectral images. The hyperspectral images were acquired by Compact Airborne Spectrographic Imager (CASI) with 1m spatial resolution and 48 bands covering the visible and near infrared portions of the solar spectrum from 370 to 1044 nm with a bandwidth of 14 nm. An object-based technique is used for classification of radish and Chinese cabbage. It was found that the optimum parameter values for image segmentation were scale 400, shape 0.1, color 0.9, compactness 0.5 and smoothness 0.5. As a result, the overall accuracy of classification was 90.7 % and the kappa coefficient was 0.71. The hyperspectral images can be used to classify other crops with higher accuracy than radish and Chines cabbage because of their similar characteristic and growth time.

• 천문학회보
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• 제41권1호
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• pp.43.4-44
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• 2016

We observed the high resolution spectra of a solar-neighborhood planetary hosting star HD 20794. The analysis of spectroscopic data was performed using URAN and SYNTHE programs. These spectra allow us to determine the effective temperatures, surface gravities, microturbulent velocities and, chemical abundances. Bond et al. (2008) found chemical abundance for 11 elements, but using the Spectrum synthesis method we have so far determine about 30 elements. We have derived iron metallicity $[FeI/H]=-0.42{\pm}0.03$, $[FeII/H]=-0.43{\pm}0.012$, and surface gravity, log g = 4.48, in good agreement with values from previous investigation.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2003년도 춘계학술대회 논문집 센서 박막재료 반도체 세라믹
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• pp.95-98
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• 2003

Tin doped indium oxide(ITO) films, which is widely used as a transparent conductor in optoelectronic devices such as solar cell, liquid crystal display, plasma display panel, thermal heater, and other sensors, were prepared by using the capacitively coupled DC magnetron sputtering method. The influence of the substrate temperature, working gas pressure and deposition time on the electrical, optical and morphological properties were investigated experimentally. ITO films with the optimum growth conditions showed resistivity of $2.36{\times}10^{-4}(\Omega}-cm$ and transmittance of 86.28% for a film 680nm thick in the wavelength range of the visible spectrum.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2003년도 하계학술대회 논문집 C
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• pp.1430-1432
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• 2003

Al doped Zinc Oxide(ZnO:Al) films, which is widely used as a transparent conductor in optoelectronic devices such as solar cell, plasma display panel, thermal heater, and other sensors, were prepared by using the capacitively coupled DC magnetron sputtering method. The influence of the substrate temperature, working gas pressure and deposition time on the electrical, optical and morphological properties were investigated experimentally. ZnO:Al films with the optimum growth conditions of working gas pressure and substrate temperature showed resistivity of $9.64{\times}10^{-4}\;{\Omega}$-cm and transmittance of 90.02% for a film 860nm thick in the wavelength range of the visible spectrum.

• 한국표면공학회지
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• 제30권2호
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• pp.136-143
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• 1997

The photvoltaic power system has received considerable attention as the petroleumalterative energies to the environmental problems in the wored scale. $CuLnSe_2$is one ofthe most promising materials for the fabrication of large-area modules and low cost photovoltaic devices. Sulfur solute CuInSe2 thin films were prepared by RF sputtering using powder targer which were previously compacted by powder of $Cu_2Se, \;In_2Se_3, \;Cu_2S, \;and\;In_2S_3$ in various ratios. The results induicated that the sulfur ratio, the(112) texture, and the energy band gap were increased by the increase of the S/(S+Se) that was controlled by stoichiometric compound. The energy band gap can be shifted from 1.04eV to 1.50eV by abjusting the S/(S+Se) ratio, which maich it possible to obtain perfect match to the solar spectrum.

• Bulletin of the Korean Chemical Society
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• 제34권4호
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• pp.1081-1088
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• 2013

Two new metal-free organic dyes bridged by anthracene-mediated ${\pi}$-conjugated moieties were successfully synthesized for use in a dye-sensitized solar cell (DSSC). A N,N-diphenylthiophen-2-amine unit in these dyes acts as an electron donor, while a (E)-2-cyano-3-(thiophen-2-yl)acrylic acid group acts as an electron acceptor and an anchoring group to the $TiO_2$ electrode. The photovoltaic properties of (E)-2-cyano-3-(5-((10-(5-(diphenylamino)thiophen-2-yl)anthracen-9-yl)ethynyl)thiophen-2-yl)acrylic acid (DPATAT) and (E)-2-cyano-3-(5'-((10-(5-(diphenylamino)thiophen-2-yl)anthracen-9-yl)ethynyl)-2,2'-bithiophen-5-yl)acrylic acid (DPATABT) were investigated to identify the effect of conjugation length between electron donor and acceptor on the DSSC performance. By introducing an anthracene moiety into the dye structure, together with a triple bond and thiophene moieties for fine-tuning of molecular configurations and for broadening the absorption spectra, the short-circuit photocurrent densities ($J_{sc}$), and open-circuit photovoltages ($V_{oc}$) of DSSCs were improved. The improvement of $J_{sc}$ in DSSC made of DPATABT might be attributed to much broader absorption spectrum and higher molecular extinction coefficient (${\varepsilon}$) in the visible wavelength range. The DPATABT-based DSSC showed the highest power conversion efficiency (PCE) of 3.34% (${\eta}_{max}$ = 3.70%) under AM 1.5 illumination ($100mWcm^{-2}$) in a photoactive area of $0.41cm^2$, with the $J_{sc}$ of $7.89mAcm^{-2}$, the $V_{oc}$ of 0.59 V, and the fill factor (FF) of 72%. In brief, the solar cell performance with DPATABT was found to be better than that of DPATAT-based DSSC.

• 생물환경조절학회지
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• 제28권1호
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• pp.86-93
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• 2019

식물의 생육과 형태는 광 환경에 영향을 받는다. 식물공장에서 재배되는 작물의 형태형성과 생육은 태양광과 다른 양상을 보이며 이는 태양광에 존재하는 원적색광 영역에 의한 영향으로 유추된다. 본 연구의 목적은 태양광 파장 유사 조합광(AS), 고압나트륨등(HPS) 및 원적색광을 추가한 고압나트륨등(HPS+FR)에서 재배된 오이의 형태형성과 생육을 비교하는 것이다. AS는 황 플라즈마 광원과 백열등, 녹색 광 차단 필름을 이용하여 제작하였다. 인공광원은 HPS를 이용하였고, 여기에 원적색광 LED를 추가하여 각 광원의 특성 및 식물의 형태형성, 생육 및 광합성 속도를 비교하였다. R/FR 값과 PSS는 AS와 HPS+FR이 유사하였다. 식물의 형태와 생육은 HPS와 HPS+FR 간에는 유의한 차이가 있었지만 AS와 HPS+FR간에는 유의한 차이가 없었다. SPAD는 HPS에서 높았으며 광합성속도는 AS와 HPS에서 높았다. HPS+FR의 광합성 속도는 HPS에 비해 낮았지만 원적색광에 의한 엽면적과 엽병 길이 증가로 인해 수광 면적이 증가하였고, 결과적으로 AS와 유사한 생육이 나타난 것으로 판단되었다. 인공광원에 원적색광을 추가하였을 때 태양광 하에서와 유사한 광형태형성 및 생육이 나타나는 것을 확인하였다. 이러한 결과로부터 식물공장에서 기존의 인공광원에 원적색광을 추가하면 동일한 효과를 얻을 수 있을 것으로 기대한다.

• 대한원격탐사학회지
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• 제38권5_1호
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• pp.647-660
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• 2022

이 단보에서는 농림위성(차세대 중형위성 4호)에 적합한 대기보정 기법 개발을 위하여, 농림위성과 공간 및 분광 해상도가 유사한 Sentinel-2 영상을 이용한 대기보정 결과를 소개하고자 한다. 대부분의 연구에서 동일한 조건에 대하여 상이한 Aerosol Optical Depth (AOD) 자료를 사용한 결과를 비교한 사례는 찾아보기 힘들다. 따라서 향후 농림위성의 대기보정에 사용될 Geo-Kompsat 2A (GK2A) Advanced Meteorological Imager (AMI)와 Aerosol Robotic Network (AERONET) AOD 입력자료를 기반으로 Fast Line-of-sight Atmospheric Analysis of Spectral Hypercubes (FLAASH), Sen2Cor, Second Simulation of the Satellite Signal in the Solar Spectrum - Vector (6SV) 버전 1.1과 2.1 모델의 대기보정 결과를 비교하였다. 모델 간 반사도 상관행렬이나 Normalized Difference Vegetation Index (NDVI) 결과를 고려해 볼 때, 6SV2.1이 보다 안정적인 모델로 사료된다.

• 대한원격탐사학회지
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• 제39권5_3호
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• pp.1061-1067
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• 2023

이 단보에서는 차세대 중형위성 4호(농림위성)의 활용에 앞서, 농림위성과 분광밴드가 유사한 Sentinel-2 위성영상에 대하여 대기보정을 모의하였다. second simulation of the satellite signal in the solar spectrum - vector(6SV)2.1 복사전달모델과 기계학습의 일종인 랜덤 포레스트(random forest, RF)를 활용하여 6SV2.1을 모사한 RF 기반의 대기보정 모델을 개발한 결과, 6SV2.1로 산출된 반사도와 RF 모델로 예측된 반사도 간의 유사도가 매우 높게 나타났다.