• 한국태양에너지학회:학술대회논문집
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• 한국태양에너지학회 2012년도 춘계학술발표대회 논문집
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• pp.248-254
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• 2012

In the situation of expanding domestic solar power supply business long-term performance modeling of a proposed solar-cooling and cleaning system to increase electromotive force and light transmission is carried out to test the effectiveness of the system. To test the effectiveness of the system, the data which comparing the solar power planet installing the system to not installing at the same time is used. A difference between the utilization factor of each comparison group were recorded. Approximately from one year to two years Field Test was performed, Result of apply to cooling/cleaning technology, Each of plant by From least 7 percent up to 16 percent utilization factor increased, and the cooling / cleaning is output through improved as a result of the determined.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2006년도 춘계학술대회
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• pp.125-129
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• 2006

This paper presents the isolation and performance evaluation of PV systems installed at Tibet area of China in order to identity the key factors that determines system operation at a severe climate conditions and promote the cooperation of PV technology between Korea and China. The installed systems consist of 100kW on-grid connected PV systems, BOS(balance of systems), data acquisition and transmission equipments. The Korea side supplied the solar cell, BOS like as inverter, control box and monitoring system. And the Chinese side assembled solar module by using Koreans solar cells, constructed site and built control house.

• Applied Microscopy
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• 제45권3호
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• pp.183-188
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• 2015

Due to the miniaturization of semiconductor devices, their crystal structure on the nanoscale must be analyzed. However, scanning electron microscope-electron backscatter diffraction (EBSD) has a limitation of resolution in nanoscale and high-resolution electron microscopy (HREM) can be used to analyze restrictive local structural information. In this study, three-dimensional (3D) automated crystal orientation and phase mapping using transmission electron microscopy (TEM) (3D TEM-EBSD) was used to identify the crystal structure relationship between an epitaxially grown CdS interfacial layer and a $Cu(In_xGa_{x-1})Se_2$ (CIGS) solar cell layer. The 3D TEM-EBSD technique clearly defined the crystal orientation and phase of the epitaxially grown layers, making it useful for establishing the growth mechanism of functional nano-materials.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2015년도 제49회 하계 정기학술대회 초록집
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• pp.196.2-196.2
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• 2015

There are various issues fabricating the successful and efficient solar cell structures. One of the most important issues is band alignment technique. The solar cells make the carrier in their active region over the p-n junction. Then, electrons and holes diffuse by minority carrier diffusion length. After they reach the edge of solar cells, there exist large energy barrier unless the good electrode are chosen. Many various conductor with different work functions can be selected to solve this energy barrier problem to efficiently extract carriers. Tungsten oxide has large band gap known as approximately 3.4 eV, and usually this material shows n-type property with reported work function of 6.65 eV. They are extremely high work function and trap level by oxygen vacancy cause them to become the hole extraction layer for optical devices like solar cells. In this study, we deposited tungsten oxide thin films by sputtering technique with various sputtering conditions. Their electrical contact properties were characterized with transmission line model pattern. The structure of tungsten oxide thin films were measured by x-ray diffraction. With x-ray photoelectron spectroscopy, the content of oxygen was investigated, and their defect states were examined by spectroscopic ellipsometry, UV-Vis spectrophotometer, and photoluminescence measurements.

• 한국전자파학회논문지
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• 제21권5호
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• pp.494-500
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• 2010

본 논문에서는 무선광 인식 장치를 새로이 제안하고 실험하였다. 무선광 인식 장치는 리더와 트랜스폰더로 구성되며, 이들은 동일한 구조로서 조명용 LED의 빛을 전송 매체로 사용하고 솔라 셀로 수신하여 서로 정보를 교환한다. 솔라 셀은 수광 표면이 넓고 평면이어서 렌즈를 사용한 광학적 정렬이 필요하지 않기 때문에 구조가 간단하고 사용이 편리하며, 관리 대상 물체의 표면에 부착하기가 용이하다. 또한 무선광 인식 장치는 빛을 전송 매체로 사용하기 때문에 RF 주파수와의 간섭이 없어 안정하다. 실험에서는 솔라 셀을 사용하여 거리가 약 1 m에서 트랜스폰더의 정보를 자동으로 인식하는 무선광 인식 장치를 구현하였다.

• 한국태양에너지학회 논문집
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• 제24권2호
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• pp.25-31
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• 2004

Ventilation through air vent system in a building envelope is expected to be an effective measure to release solar radiation. An external surface of a wall absorbs solar radiation and transfers it to the air in the cavity. The warmed air gets buoyant force. So when openings are provided at the top and bottom of the cavity, the warmed air is released through the top opening and cooler outside air replaces the space in the cavity. This reduces the further heat transmission into the built environment. This natural ventilation effect seems to be steady and strong. So because of the cavity and the openings, the cooling load reduction by natural ventilation is believed to be considerable.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2014년도 제46회 동계 정기학술대회 초록집
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• pp.467.1-467.1
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• 2014

Quantum dots (QD) solar cells has received considerable attention due to their potential of improving the overall conversion efficiency by harvesting excess energy via multiple excitons generation (MEG). Although there have been many reports which show MEG phenomena by using optical measurement of quantum dots themselves, carrier multiplication in real QD photovoltaic devices has been sparsely reported due to difficulty in dissociation of excitons and charge collection. In this reports, heterojunction QD solar cells composed of PbS QD monolayer on highly crystalline $TiO_2$ thin films were fabricated by using Langmuir-Blodgett deposition technique to significantly reduce charge recombination at the interfaces between each QD. The PbS CQDs monolayer was characterized by using UV-vis, transmission electron microscopy (TEM) and atomic force microscopy (AFM). The internal quantum efficiency (IQE) for the monolayer QD solar cells was obtained by measurement of external quantum efficiency and determining light absorption efficiency of active layer. Carrier multiplication was observed by measuring IQE greater than 100% over threshold photon energy. Our findings demonstrate that monolayer QD solar cell structure is potentially capable of realizing highly efficient solar cells based on carrier multiplication.

• 한국태양에너지학회 논문집
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• 제31권4호
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• pp.66-71
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• 2011

This study focused on the application of the Passive Solar Chamber System (PSCS) as proposed by a previous study. The seasonal performance and sizing method for the system were investigated for a feasibility of the PSCS in Korean climate. For seasonal performance, heat and ventilation performances of the PSCS were analyzed for the months of January and August. This study proposed a simple configuration method in which the designer can decide on the system size at the preliminary design stage by using system efficiency, overall heat transfer coefficient transmission, monthly solar radiation, highest and lowest temperatures. During weeks that require heating, the system showed to acquire a daily average heat amount of $860.28Wh/m^2$ day. For cooling periods, the system was computed to supply a daily average natural ventilation of $1,360.2m^3/day$ to the room. Moreover, proposed sizing method and the overall computation results showed a 6.04~7.24% error of assessment.

• International Journal of Internet, Broadcasting and Communication
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• 제13권2호
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• pp.93-102
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• 2021

In this research, we present a natural lighting system with transmission distance of 30m and lighting efficiency of 35% (30m standard) for operating hours of 7h/day (based on clear sky). The system is composed of parabolic reflective mirror and modified light pipe that can secure more than 88% of light concentration efficiency. The light loss rate of newly designed light pipe transmission system is demonstrated to 0.8 %/m in the straight-line part and 2%/m in the curved part. Modified light pipe daylighting system shows better performance over fiber optic daylighting system in terms of transmission distance (1.5 times longer) and illuminance (3.05 times higher).

• 전기전자학회논문지
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• 제23권4호
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• pp.1448-1456
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• 2019

본 연구에서는 작물재배용 단동식 유리온실 내에 LED 광원을 적용할 때, LED의 전원 공급을 위한 태양전지를 에너지 저감과 광투과율을 고려하여 Si 계열의 태양전지와 염료감응형 태양전지(DSSC)를 유리온실에 선별적 배치하고, 작물 재배에 유효한 태양전지의 광투과율을 결정하기 위해 유리온실의 천정과 측면에 대해 광투과율 변화에 따른 조도 시뮬레이션을 수행하였다. 또한, 유리온실에서 주광과 인공광인 LED 광원을 모두 고려하는 경우 최적 조명제어에 따른 유리온실의 에너지 절감 효과를 분석하였다.