• 제목/요약/키워드: Jang suk-sun

검색결과 279건 처리시간 0.022초

Mechanical Properties and Microstructure of Nano Grain Nickel Alloy Deposit

  • Seo, Moo Hong;Kim, Jung Su;Kim, Seung Ho;Wyi, Jung Il;Hwang, Woon Suk;Jang, Si Sung;Jung, Hyun Kyu;Chun, Byung Sun
    • Corrosion Science and Technology
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    • 제2권4호
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    • pp.197-201
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    • 2003
  • In this study, Ni-P layers were electroplated on the surface of stainless steel in order to investigate the effects of an additive and agitation on their mechanical properties and microstructure. The concentration of the additive in the plating solution increased, the pores formed in the layer decreased, while the residual stress developed in the layers during electroplating increased. Agitation of the solution during electroplating was observed to force to increase local pores in the layer, which lowers its tensile properties. Grain growth was suppressed due to very fine $Ni_3P$ precipitates formed at its grain boundaries during heat treatment at $343^{\circ}C$ for 1 hr in air.

내부(內部)에 삼각형(三角形) 핀이 부착(附着)된 회전형(回轉型) 히이트파이프의 전열특성(傳熱特性) (Heat Transfer Characteristics for Internally Triangular finned Rotating Heat Pipes)

  • 권순석;전철호;장영석;서해성
    • 태양에너지
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    • 제9권1호
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    • pp.43-52
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    • 1989
  • Heat transfer rate and heat flux from the condenser with internally triangular fins rotating heat pipe has been numerically studied by finite element method. The results of numerical and P.J. Martos' experimental showed good agreement and it was able to predict to the performance of a rotating heat pipe. By increasing fin half angle or fin height, heat transfer rate from condenser was increased slightly but heat flux was decreased. By increasing condenser radius or r.p.m. of rotating heat pipe, heat transfer rate and heat flux was increased rapidly. Heat transfer rate was rapidly increased with increasing fin numbers in case of few fm numbers but slowly increased at many fin numbers. So the optimum fin numbers were a half of maximum fin numbers which was able to install in the condenser of a rotating heat pipe.

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OLED TV Panel의 전류가속열화시험 설계 (Electric Current Accelerated Degradation Test Design for OLED TV)

  • 유지선;이득중;오창석;장중순
    • 한국신뢰성학회지:신뢰성응용연구
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    • 제17권1호
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    • pp.22-27
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    • 2017
  • Purpose: The purpose of this study is to estimate the life time of OLED TV panel through electric current ADT(Accelerated Degradation Test). Methods: We performed accelerated degradation test for OLED TV Panel at the room temperature to avoid high temperature impact on the luminance. Results: we got more accurately the life time of the OLED TV when we applied ADT without temperature factor than including both current and temperature. Conclusion: Until now, the ADT of the OLED TV has been conducted with temperature and current at the same time for reducing test time and costs. We estimate incorrect life time when the temperature is adopted as an accelerated factor. Due to the high temperature impact on the luminance of the OLED TV panel. So as to solve this problem, we discard temperature and use electric current only.

특정 고조파 제거를 위한 Cascaded H-bridge 7레벨 인버터의 특성해석 및 시뮬레이션 (Analysis and simulation of Cascaded H-bridge 7 level inverter for eliminating typical harmonic waveforms)

  • 진선호;오진석;조관준;곽준호;임명규;김장목
    • 한국마린엔지니어링학회:학술대회논문집
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    • 한국마린엔지니어링학회 2005년도 전기학술대회논문집
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    • pp.1022-1028
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    • 2005
  • This paper is presented the analysis results and simulation results of cascaded H-bridge 7 level inverter with various modulation index. Stepped waveform having number of switching was used to eliminate harmonic components. Switching angles according to modulation index are calculated numerically. Therefore, 3 times of switching with 7 level topology and QWS(Quarter Wave Symmetry) could eliminate 5th and 7th harmonics. The harmonic characteristics are compared to those of space vector modulation method which known as common modulation method in industrial field. Stepped waveform method showed higher ability to reduce, especially lower order of harmonics.

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Pt Thickness Dependence of Oscillatory Interlayer Exchange Coupling in [CoFe/Pt/CoFe]/IrMn Multilayers with Perpendicular Anisotropy

  • Lee, Sang-Suk;Choi, Jong-Gu;Kim, Sun-Wook;Hwang, Do-Guwn;Rhee, Jang-Roh
    • Journal of Magnetics
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    • 제10권2호
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    • pp.44-47
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    • 2005
  • The oscillatory interlayer exchange coupling (IEC) has been shown in pinned $[CoFe/Pt(t_{pt})/CoFe]/IrMn$ multi-layers with perpendicular anisotropy. The period of oscillation corresponds to about 2 monolayers of Pt. The oscillatory behavior of IEC depending on the nonmagnetic metallic Pt thickness is thought to be related the antiferromagnetic ordering induced by IrMn layer. Oscillatory IEC as function of insulating NiO thickness has been observed in $[Pt/CoFe]_4/NiO(t_{NiO})/[CoFe/Pt]_4$ multilayers. The effect of N (number of bilayer repeats) upon the magnetic property of [Pt/CoFe]N/IrMn is also studied.

Overexpression of SMP30 Inhibit Radiation-Induced Apoptosis in Smad3-Knockout Mice Liver

  • Jeong, Da-Hee;Hong, Il-Hwa;Do, Sun-Hee;Yang, Hai-Jie;Yuan, Dong-Wei;Seo, Mi-Na;Jo, Jae-Chung;Lee, Seung-Sook;Jang, Won-Suk;Kim, Tae-Hwan;Jeong, Kyu-Shik
    • 한국수의병리학회:학술대회논문집
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    • 한국수의병리학회 2005년도 Proceedings of The 2nd Asian Society of Veterinary Pathology Symposium(Vol.2) and 2005 Annual Meeting of The Korean Society of Veterinary Pathology(Vol.9)
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    • pp.91.1-92
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    • 2005
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Case of Sporadic T-cell Lymphomsarcoma in a Cattle

  • Jeong, Da-Hee;Do, Sun-Hee;Hong, Il-Hwa;Jang, Seong-Joon;Lee, Suk-Hwan;Lee, Young-Ha;Cho, Eun-Mi;Park, Jin-Kyu;Moon, Sung-Hwan;Jeong, Kyu-Shik
    • 한국수의병리학회:학술대회논문집
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    • 한국수의병리학회 2005년도 Proceedings of The 2nd Asian Society of Veterinary Pathology Symposium(Vol.2) and 2005 Annual Meeting of The Korean Society of Veterinary Pathology(Vol.9)
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    • pp.93-94
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    • 2005
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Duck Hepatitis in a Duckling

  • Kim, Dong-Hwan;Son, Young-Suk;Kim, Ki-Seok;Hong, Il-Hwa;Jeong, Da-Hee;Do, Sun-Hee;Yang, Hai-Jie;Yuan, Dong-Wei;Jang, Seong-Joon;Jeong, Kyu-Shik
    • 한국수의병리학회:학술대회논문집
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    • 한국수의병리학회 2005년도 Proceedings of The 2nd Asian Society of Veterinary Pathology Symposium(Vol.2) and 2005 Annual Meeting of The Korean Society of Veterinary Pathology(Vol.9)
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    • pp.102-103
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    • 2005
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과학기술발전과 진흥…이것부터

  • 권숙일;조남진;오정무;이은웅;백장현;박영호;이광영;강박광;윤영훈;권순찬;김동한;김창식;권선록;김경제;박택규;김명자;권태완;김진수;정완호;김주목
    • 과학과기술
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    • 제25권2호통권273호
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    • pp.8-44
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    • 1992
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