• 제목/요약/키워드: Film performance

검색결과 2,487건 처리시간 0.035초

OLED Anode용 IZO 박막의 기판 온도에 따른 특성 (The Performance of IZO Thin Film with Substrate Temperature for OLED Anode)

  • 홍정수;김경환
    • 반도체디스플레이기술학회지
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    • 제8권3호
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    • pp.51-55
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    • 2009
  • We investigated that electrical and optical the properties of IZO thin film for OLED anode application. The IZO thin film was the deposited on the glass substrate by facing targets system as a function of substrate temperature. As a result, the electrical and optical property of IZO thin film prepared with $150^{\circ}C$ was most excellent. To confirm the suitability of the IZO thin film for OLED anode, we evaluated the performance of OLED with IZO/TPD/Alq3/LiF/Al fabricated on IZO anode. Also, the performance of OLED fabricated on IZO anode showed the most excellent at $150^{\circ}C$ substrate temperature.

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수평단관 상의 유하액막 열전달 (Falling Film Heat Transfer on a Horizontal Single Tube)

  • 김동관;김무환
    • 설비공학논문집
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    • 제12권7호
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    • pp.642-648
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    • 2000
  • Falling film heat transfer analyses with aqueous lithium bromide solution were peformed to investigate the transfer characteristics of the copper tubes. Finned(knurled) tube and a smooth tube were selected as test specimens. Averaged generation fluxes of water and the heat transfer performances(heat flux, heat transfer coefficient) were obtained. The results of this work were compared with the data reported previously. As the film flow rate of the solution increased, the generation fluxes of water decreased for both tubes. The reason is estimated by the fact that the heat transfer resistance with the film thickness increased as the film flow rate increased. The effect of the enlarged surface area at the knurled tube was supposed to be dominant at a small flow rate. The generation fluxes of water increased with the increasing degree of tube wall superheat. Nucleate boiling is supposed to occur at a wall superheat of 20 K for a smooth tube, and at 10 K for a knurled tube. The heat transfer performance of the falling film was superior to pool boiling at a low wall superheat below 10 K for both tubes tested. The knurled tube geometry showed good performance than the smooth tube, and the increased performance was mainly came from the effect of the increased heating surface area.

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다양한 막냉각 홀 형상에 대한 막냉각 효율의 수치해석 (NUMERICAL STUDY ON FILM-COOLING EFFECTIVENESS FOR VARIOUS FILM-COOLING HOLE SCHEMES)

  • 김선민;이기돈;김광용
    • 한국전산유체공학회:학술대회논문집
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    • 한국전산유체공학회 2011년 춘계학술대회논문집
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    • pp.104-111
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    • 2011
  • To protect the turbine blade, many cooling techniques has developed. With all other things, film-cooling has been widely used as the important alternative. In the present work, numerical analysis has been performed to investigate and to compare the film-cooling performance of various film-cooling hole schemes such as cylindrical, crescent, louver, and dumbbell holes. To analyze the turbulent flow and the film-cooling mechanism, three-dimensional Reynolds-averaged Navier-Stokes analysis has been performed with shear stress transport turbulence model. The validation of numerical results has been assessed in comparison with experimental data. The characteristics of fluid flow and the film-cooling performance for each shaped hole have been investigated and evaluated in terms of centerline, laterally averaged and spatially averaged film-cooling effectivenesses. The dumbbell shaped hole shows better film-cooling effectiveness than other shaped holes. And the louver and cylindrical shaped hole shows lower one, and concentrated flow on centerline only.

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수직 액막 흡수관의 유동변화에 따른 흡수성능 변화에 관한 해석적 연구 (Numerical Study on the change of Absorption Characteristics by Change of Flow pattern in the Vertical Falling Film Absorber)

  • 김정국;조금남
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2003년도 추계학술대회
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    • pp.90-96
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    • 2003
  • Numerical analyses have been performed to obtain the absorption heat and mass transfer coefficients and the absorption mass flux from a falling film of LiBr solution. In the present study, the behavior of laminar-wavy falling film in the vertical absorber was studied analytically and experimentally. The change of absorption performance on mean film thickness, wave amplitude, wave celerity was analysed. The heat and mass transfer equations are solved simultaneously to give the temperature and concentration variations at the LiBr solution/refrigeration vapor interface and at the wall. Effects of uniform film, wavy film and film Reynolds number on the heat and mass transfer coefficients have been estimated. The analytical results of the uniform and wavy falling film in the bare tube was higher than experimental result for $Rd_{t}<100$. The absorption performance showed the maximum at the wavy film by the insert device(spring).

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비파괴검사 장치 내 방사선원 위치감시용 섬광필름의 발광성능 평가 (Evaluation of luminance performance of scintillating film for monitoring the position of a radioactive source in an NDT apparatus)

  • 이경진;윤정익;박병기;김신;이봉수
    • 대한방사선기술학회지:방사선기술과학
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    • 제28권1호
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    • pp.13-17
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    • 2005
  • 최근 비파괴검사 현장에서 검사 중 검사장치 내 방사선원의 위치를 확인하지 못하여 방사선 과피폭 사고가 종종 발생하고 있다. 본 연구는 방사선원의 노출여부나 위치 미인지로 인한 방사선 사고를 예방하기 위해 방사선원위치를 감시할 수 있는 섬광필름을 개발하는데 있다. 섬광필름은 방사선 비파괴 검사 장비의 가이드튜브 내에 존재하는 선원의 위치를 육안으로 탐지할 수 있는 신소재이다. 연구를 통해 섬광필름의 발광성능을 평가하고 최적의 필름 설계를 꾀하였다. 필름에 적용된 발광물질은 무기 섬광체를 이용하였고, 다양한 층을 갖는 형태의 필름을 제작하여 성능을 평가하였다. 필름의 발광성능은 광도계를 이용하여 측정하였고, 비파괴 검사장비는 Ir-192 감마선 조사기를 사용하였다. 실험결과, 섬광필름의 발광은 육안으로 선원의 위치를 감시할 수 있었으며, 선원의 이동에 따라서 발광영역도 동시에 이동하면서 형성되었다. 또한, 섬광필름에 반사층을 두는 것은 광 이용률의 증대시켜 발광성능을 높이는 데 매우 효과적이었다. 섬광체와 분산용제의 혼합비에 따라서도 성능변화가 나타났으며, 일반적으로 섬광체의 양이 높을수록 발광성능은 높게 나타났다. 그러나 분산 특성이 변화로 혼합비는 일정 농도 이하로 제한되었다. 섬광체 중에서는 $Gd_2O_2S(Tb)$ 무기섬광체가 가장 높은 발광성능을 보여주었다. 개발된 섬광필름을 비파괴 검사 장비에 적용하게 된다면 방사선종사자에게 보다 안전한 작업환경을 제공할 수 있을 것이다.

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더블로이유리 적용 창호의 구성요소에 따른 단열성능 비교 실험 (A Comparison of Thermal Performance of Double Low-E Glazing Window according to Various Material)

  • 장철용;안병립;김치훈;김준섭;이성재
    • 한국태양에너지학회:학술대회논문집
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    • 한국태양에너지학회 2011년도 춘계학술발표대회 논문집
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    • pp.133-137
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    • 2011
  • Low-e glazing is classified as soft low-e glazing and hard low-e glazing. Hard low-e glazing can be temperable and its handling is comfortable because its coating film is a oxide film generated at high temperatures. But there is a fatal weakness that its insulation performance and shielding performance are lower compared to soft low-e glazing by low electrical conductivity of coating film. Soft low-e glazing is excellent because its coating film consists of Ag that is excellent electrical conductivity and it has strength that can supply various product consumers want. But soft low-e glazing has weaknesses that temperable and handling are difficult because Ag is oxidized easily. Therefore this study analyzes thermal performance of glazing by changing filling gas according to applying low-e glazing through simulation to judge performance before making sample. After this process, a comparative experimental study was done through TVS by making temperable low-e glazing.

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Effect of Hydrogen Treatment on Anatase TiO2 Nanotube Arrays for Photoelectrochemical Water Splitting

  • Kim, Hyun Sik;Kang, Soon Hyung
    • Bulletin of the Korean Chemical Society
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    • 제34권7호
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    • pp.2067-2072
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    • 2013
  • Hydrogen ($H_2$) treatment using a two-step $TiO_2$ nanotube (TONT) film was performed under various annealing temperatures from $350^{\circ}C$ to $550^{\circ}C$ and significantly influenced the extent of hydrogen treatment in the film. Compared with pure TONT films, the hydrogen-treated TONT (H:TONT) film showed substantial improvement of material features from structural, optical and electronic aspects. In particular, the extent of enhancement was remarkable with increasing annealing temperature. Light absorption by the H:TONT film extended toward the visible region, which was attributable to the formation of sub-band-gap states between the conduction and valence bands, resulting from oxygen vacancies due to the $H_2$ treatment. This increased donor concentration about 1.5 times higher and improved electrical conductivity of the TONT films. Based on these analyses and results, photoelectrochemical (PEC) performance was evaluated and showed that the H:TONT film prepared at $550^{\circ}C$ exhibited optimal PEC performance. Approximately twice higher photocurrent density of 0.967 $mA/cm^2$ at 0.32 V vs. NHE was achieved for the H:TONT film ($550^{\circ}C$) versus 0.43 $mA/cm^2$ for the pure TONT film. Moreover, the solar-to-hydrogen efficiency (STH, ${\eta}$) of the H:TONT film was 0.95%, whereas a 0.52% STH efficiency was acquired for the TONT film. These results demonstrate that hydrogen treatment of TONT film is a simple and effective tool to enhance PEC performance with modifying the properties of the original material.

빅데이터를 활용한 영화흥행 요인 분석: 영화 <기생충>의 SNS 활용지수와 토픽키워드 중심으로 (Analyzing Factors of Success of Film Using Big Data : Focusing on the SNS Utilization Index and Topic Keywords of the Film )

  • 김진욱
    • 한국엔터테인먼트산업학회논문지
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    • 제14권4호
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    • pp.145-153
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    • 2020
  • 빠르게 변화하고 있는 4차 산업 시대에 빅데이터는 다양한 분야에 활용되고 있다. 최근 문화예술콘텐츠 전반에도 빅데이터의 활용은 급속도로 적용되고 있고, 그중에서도 영화는 자본이 많이 드는 예술장르로서 빅데이터의 활용은 매우 유용한 분석 수단이다. 본 연구는 2019년 제72회 칸 영화제의 황금종려상과 아카데미 시상식에서 4관왕(작품상, 감독상, 각본상, 외국어 영화상)을 차지하며 한국영화의 가치를 보여준 영화 <기생충>을 대상으로 빅데이터 분석기법을 적용하여 실시하였다. 이렇게 분석된 값은 데이터의 주기별 변화량과 감성의 값을 부여하는 오피니언 마이닝을 통해 영화 흥행을 예측하고, 페이스북(Facebook), 트위터(Twitter) 등 SNS의 활용지수와 토픽 키워드를 추출하여 관객들의 관심을 반영하는 영화적 요인들이 무엇인지를 살펴보았다. 이처럼 빅데이터를 활용한 영화흥행 요인분석으로 모델 구축 및 모형 개발로 흥행예측이 가능해지면 영화제작 과정의 효율성을 극대화하면서 제작비용과 영화실패에 따른 리스크를 최소화 할 것이다.

엑시머 레이저를 이용하여 동시에 형성된 실리콘 산화막과 다결정 실리콘 박막 (Silicon oxide and poly-Si film simultaneously formed by excimer laser)

  • 박철민;민병혁;전재홍;유준석;최홍석;한민구
    • 전자공학회논문지D
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    • 제34D권1호
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    • pp.35-40
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    • 1997
  • A new method to form the gate oxide and recrystllize the polycrystalline silicon (poly-Si) active layer simultaneously is proposed and fabricated successfully. During te irradiation of excimer laser, the poly-Si film is recrystallized, while the oxygen ion impurities injected into the amorphous silicon(a-Si) film are activated by laser energy and react with silicon atoms to form SiO2. We investigated the characteristics of the sample fabricated by proposed method using AES, TEM, AFM. The electrical performance of oxide was verified by ramp up voltage method. Our experimental results show that a high quality oxide, a pol-Si film with fine grain, and a smooth and clean interface between oxide and poly-Si film have been successfully obtained by the proposed fabrication method. The interface roughness of oxide/poly-Si fabricated by new method is superior to film by conventional fabrication os that the proposed method may improve the performance of poly-Si TFTs.

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