• Journal of Korea Society of Industrial Information Systems
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• v.19 no.1
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• pp.31-41
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• 2014

The satellite on geostationary orbit accommodates multiple payloads into a single spacecraft platform and launched in June 26, 2010. The Electrical Power Subsystem provides a fully regulated power bus at $50V_{DC}$ in sunlight and eclipse conditions. The electrical power required to the satellite is generated by a solar array wing and the energy is stored by a Li-Ion battery with a capacity of 192.5Ah. This paper selects the main design parameters, compares and analyzes with the results at ground test and in orbit operation to apply this performance evaluation of the Electrical Power Subsystem to next satellite design on geostationary orbit. The Electrical Power Subsystem is demonstrated nominal behavior without significant degradation through the performance evaluation from design to in orbit operation.

• 한국신재생에너지학회:학술대회논문집
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• 2007.11a
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• pp.462-465
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• 2007

석탄가스화 수소생산 기술 분야는 석탄 등의 화석연료를 이용하여 고온, 고압하에서 반응가스(산소, 수증기, 수소)와의 화학적 반응을 통해 생산된 연소성 가스 ($H_2$, CO, $CO_2$ 등)를 전환반응(WGS) 및 분리반응을 거쳐 효율적으로 청정하게 수소를 생산해 내는 기술이다. 전력산업에서 석탄가스화 수소생산은 그 사용 방법(연료전지, 수소 터빈, 분산 이용 등)에 따라 발전시스템의 고효율화를 지향하고, zero-emission을 실현하는 첨단 발전 시스템의 종합 구현을 목표로 하고 있으며, 더불어, 도래하는 수소 경제로의 전이에 대비에 석탄을 이용한 중앙(Central) 수소생산 시스템을 구현하여 이송 및 전환을 통한 지역적 분산 이용을 가능케 하는 종합적인 인프라를 구축하는 기술이다. 본 기술에는 석탄가스화 기술, 수성가스 전환기술, 수소/$CO_2$ 분리기술, 이송용 연료 전환기술 등이 포함된다. 석탄가스화 수소생산 기술은 급등하는 오일 가격과 이의 수입사용 증가에 대응하기 위한 에너지 안보 대책 마련 및 효율 극대화의 필요성과 더불어, 전력산업에서 화력 발전시스템의 궁극적 실현 목표인 고효율, 초청정의 전력생산 시스템의 구현을 가능케 하여, 향후 화석 연료를 이용한 미래 발전 기술을 선도 할 것으로 기대된다. 더불어, 수소 경제로의 전환 시 수소 수요의 급팽창에 대비한 경제적인 대규모 수소생산 기술의 개발이 필요하며, 이에 기술 실현성이 가장 높은 석탄가스화 수소생산 기술의 개발 구현이 요구된다.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2013.05a
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• pp.471-473
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• 2013

This paper is analyzing the situation of the electric vehicle Industry and draw the policy implications to promote electric vehicle industry. Major automobile makers as GM, BMW, Nissan, Audi produce various electric vehicles. But in recent times, only few electric vehicle sold in the world. So, many automobile makers gave up the production of electric vehicles. and the fuel-cell vehicle will replace the electric vehicle as a environment car in the future. We should take the build up of eco system between vehicle makers and the small parts companies, construction of battery charging infrastructure, promotion of standardization activities, and the government's support to revive the electric vehicle industry.

• Journal of Digital Convergence
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• v.14 no.2
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• pp.141-148
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• 2016

Agricultural machines can be viewed as a very important factor to reduce the workforce and reduce production costs as well as keep up with now days trend caused Labor shortages and the workforce reduction by aging in rural. The latest agricultural machinery has developed into a major agricultural industry to apply and integrate the telecommunication, next-generation batteries, semiconductors, wireless communications, content and high-tech display industry technology with a wide range of applications. In this study, to apply the information and communication technologies on agricultural planters relied on a mechanical method, we designed a quick and sophisticated ICT convergence planters that enable to monitor.

• Industry Promotion Research
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• v.1 no.1
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• pp.7-11
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• 2016

It was the electrical properties of IGZO prepared by the annealing in a vaccum and an atmosphere conditions to research the current-voltage characteristics. The IGZO film annealed in a vaccum became an amorphous structure but films annealed in an atmosphere condition had a crystal structure. Because of the content of oxygen vacancies during the annealing processes was changed, and the annealing in an atmosphere condition increased the oxygen vacancy in IGZO. Oxygen vacancy in IGZO increased the current and then it was observed the Ohmic contact at IGZO annealed in an atmosphere conditions. However, the IGZO prepared in a vaccum showed the Schottky contact.

• Journal of Radiation Industry
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• v.4 no.4
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• pp.359-364
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• 2010

PVDF-HFP (binder)/silylated alumina (inorganic particle)-coated PE (polyethylene) separators were with various compositions of binder and inorganic particle were prepared by a dip-coating process with humidity control (R.H. 25% and 50%) using electron beam irradiation. The morphology of the coated PVDF-$HFP/Al_2O_3$ layer with various compositions of PVDF-HFP and $Al_2O_3$, and humidity condition was found to be an important factor in determining ionic conductivity of the prepared separators. The PVDF-$HFP/Al_2O_3$ (5/5)-coated PE separator prepared at R.H. 50% followed by electron beam irradiation at 200 kGy was applied for lithium-ion polymer battery and the cell test results showed improved high-rate discharge performance and better cyclic stability compared to the cells with the bare PE and the PVDF-HFP-coated PE separators.

• Journal of Radiation Industry
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• v.9 no.4
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• pp.167-170
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• 2015

Radioisotope (Nuclear) battery using $^{63}Ni$ was prepared as beta cell. The electroplated $^{63}Ni$ on Ni foil is fabricated, and beta cell and photovoltaic hybrid battery was designed to use at both day and night in space project. A Ni-plating solution is prepared by dissolving metal particles including $^{62}Ni$ and $^{63}Ni$ from neutron irradiation of ($n,{\gamma}$). Electroplating solution of a chloride bath consists on nickel ions in HCl, $H_3BO_3$, and KOH. The deposition was carried out at current density of $10mA\;cm^{-2}$. The prepared beta source was attached on a PN junction and measured I-V properties. The power output at activity of 0.07 mCi and 0.45 mCi were 0.55 pW and 2.69 nW, respectively.

• Journal of Radiation Industry
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• v.11 no.3
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• pp.173-179
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• 2017

The small-scale electroplating device was designed and fabricated for Ni-63 sealed source (foil type) with a high specific activity needed for production of betavoltaic battery. The condition of Ni electroplating was optimized by using fabricated electroplating device to establish a Ni-63 electroplating condition on the Ni foil. The results showed that the optimum surface morphology and thickness of Ni deposit was obtained for 1,758 seconds at a current density of $15mA{\cdot}cm^{-2}$ with 0.5% tween 20. Radioisotope Ni-63 electroplating was implemented under established condition. The radioactivity of Ni-63 sealed source was calculated to $28mCi{\cdot}cm^{-2}$, and the thickness of Ni-63 deposit was about $2.4{\mu}m$.

• Journal of Radiation Industry
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• v.8 no.1
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• pp.17-22
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• 2014

In this study, we prepared CdTe/CdS solar cells using a thermal vacuum evaporation method. In particular, $CdCl_2$ treatment was attempted using this same method at $400^{\circ}C$ for 30 min. The prepared CdTe/CdS solar cells were investigated using Fouier transform infrared spectrometry (FTIR), field emission scanning electron microscopy (FE-SEM), and a solar simulator system including light absorption properties, morphological properties, and power conversion efficiency (PCE). In addition, we investigated the gamma-irradiation treatment at dose rates of 0 Gy, 500 Gy, 1 kGy, 10 kGy, and 30 kGy. The characteristics of gamma-irradiation treatment were studied based on the same method described above. In particular, it showed increased values as 0.826% higher than the non-irradiation of 0.448% from PCE analysis.

• Journal of the Korea Safety Management & Science
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• v.20 no.4
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• pp.7-13
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• 2018

This study investigates the enhancement of the oxygen diffusion rate in the cathode channel of a proton exchange membrane fuel cell (PEMFC) by pure oscillating flow, which is the same as the mechanism of human breathe. Three-dimensional numerical simulation, which has the full model of the fuel cell including electrochemical reaction, ion and electronic conduction, mass transfer and thermal variation and so on, is performed to show the phenomena in the channel at the case of a steady state. This model could analysis the oscillating flow as a moving mesh calculation coupled with electrochemical reaction on the catalyst layer, however, it needs a lot of calculation time for each case. The two dimensional numerical simulation has carried on for the study of oscillating flow effect in the cathode channel of PEMFC in order to reduce the calculation time. This study shows the diffusion rate of the oxygen increased and the emission rate of the water vapor increased in the channel by oscillating flow without any forced flow.