• 제목/요약/키워드: Single layer structure

검색결과 693건 처리시간 0.026초

ZnS:Cu를 이용한 후막 전계발광소자의 고휘도 특성 (High brightness property of Power Electroluminescent Device using ZnS:Cu)

  • 이종찬;박대희
    • 대한전기학회논문지:전기물성ㆍ응용부문C
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    • 제48권5호
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    • pp.349-353
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    • 1999
  • In this paper, to fabricate the AC power electroluminescent device (PELD) with high brightness, new structure that constructed single emissive layer between electrodes was proposed. Dielectric and phosphor material structure that constructed single emissive layer between electrodes was proposed. Dielectric and phosphor material were BaTiO3 and ZnS:Cu respectively. Fabricated AC power EL devices were estimated by optical and electrical properties of EL spectrum, brightness, CIE coordinate system, transferred charge density and EL emission wave in time domain. With above results, we found that brightness of newly proposed AC powder EL power EL device was 2754 cd/m2 at 100V, 400 Hz and compared with conventional device structure.

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Metastable Vortex State of Perpendicular Magnetic Anisotropy Free Layer in Spin Transfer Torque Magnetic Tunneling Junctions

  • You, Chun-Yeol;Kim, Hyungsuk
    • Journal of Magnetics
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    • 제18권4호
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    • pp.380-385
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    • 2013
  • We find a metastable vortex state of the perpendicular magnetic anisotropy free layer in spin transfer torque magnetic tunneling junctions by using micromagnetic simulations. The metastable vortex state does not exist in a single layer, and it is only found in the trilayer structure with the perpendicular magnetic anisotropy polarizer layer. It is revealed that the physical origin is the non-uniform stray field from the polarizer layer.

자기유도방식 무선전력전송 시스템 송수신 코일의 Multi-layer 구조에 따른 자기결합 특성 (Multi-layer Structure of Transceiver Coils Magnetic Coupling Characteristics for Inductive Power Transfer System)

  • 김철민;유재곤;김종수
    • 전력전자학회:학술대회논문집
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    • 전력전자학회 2018년도 전력전자학술대회
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    • pp.298-299
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    • 2018
  • 본 논문에서는 자기유도방식 무선전력전송(Inductive Power Transfer, IPT) 시스템에 적용되는 송수신 코일의 Multi-layer 구조의 자기결합 특성에 대하여 분석한다. 기존에 제안된 Single-layer 구조의 코일과 Multi-layer 구조의 코일이 가지는 차이점을 자기결합도 측면에서 비교 분석하고 이를 Simulation 및 실험을 통해 검증한다.

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The effects of temperature and vacancy defect on the severity of the SLGS becoming anisotropic

  • Tahouneh, Vahid;Naei, Mohammad Hasan;Mashhadi, Mahmoud Mosavi
    • Steel and Composite Structures
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    • 제29권5호
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    • pp.647-657
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    • 2018
  • Geometric imperfections may be created during the production process or setting borders of single-layer graphene sheets (SLGSs). Vacancy defects are an instance of geometric imperfection, so investigating the effect of these vacancies on the mechanical properties of single-layer graphene is extremely important. Since very few studies have been conducted on the structure of imperfect graphene (with the vacancy defect) as an anisotropic structure, further study of this defective structure seems imperative. Due to the vacancy defects and for the proper assessment of mechanical properties, the graphene structure should be considered anisotropic in certain states. The present study investigates the effects of site and size of vacancy defects on the mechanical properties of graphene as an anisotropic structure using the lekhnitskii interaction coefficients and Molecular Dynamic approach. The effect of temperature on the severity of the SLGS becoming anisotropic is also investigated in this study. The results reveal that the amount of temperature has a big effect on the severity of the structure getting anisotropic even for a graphene without any defects. The effect of aspect ratio, temperature and also size and site of vacancy defects on the material properties of the graphene are studied in this research work. According to the present study, using material properties of flawless graphene for imperfect structure can lead to inaccurate results.

설비하중을 고려하는 단층래티스돔의 좌굴특성에 관한 연구 (A Study on the Buckling Characteristics of Single-Layer Latticed Domes under Equipment-Loading)

  • 박지영;정환목;권영환
    • 한국전산구조공학회:학술대회논문집
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    • 한국전산구조공학회 1994년도 봄 학술발표회 논문집
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    • pp.83-88
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    • 1994
  • Recently, the equipments of the structure are increasing remarkably. It is very important to evaluate the stability of the domes under concentrated loading such as a large-scale illuminating, visional, and sound equipment. The paper is aimed at investigating the buckling characteristics of single-layer latticed domes with triangular network under the uniformly distributed vertical-loading and the partially concentrated equipment-loading. The results show that the effects of the equipment-loading on the buckling strength is much more sensitive in domes of overall buckling than in domes of member buckling.

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접합부 강성변화를 고려한 단층 래티스 돔의 좌굴해석 (Buckling Analysis for Single Layer Latticed Domes considering the Change of Joint Rigidity)

  • 이후진;권택진
    • 한국전산구조공학회:학술대회논문집
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    • 한국전산구조공학회 2001년도 가을 학술발표회 논문집
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    • pp.337-344
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    • 2001
  • This paper is concerned with the change of joint rigidity in estimating the degree of semi-rigidity of connections and the buckling load in a single layer latticed dome. The estimations are based on information about the ratio for the rotational stiffness of the connection to the flexural stiffness of the member and the minimum eigenvalue of a structure for pinned, semi-rigid and completely rigid cases, respectively. Connection characteristics are reflected in the ratio control of joint rigidity for the DOFs to be related using the spring element by FEM.

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단층 래티스 돔의 비탄성 거동에 대한 실험연구 (Experimental Study on the Inelastic Behavior of Single-layer Latticed Dome)

  • 김종수;김상대;김명한;오명호;신창훈
    • 한국공간구조학회:학술대회논문집
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    • 한국공간구조학회 2008년도 춘계 학술발표회 논문집
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    • pp.165-170
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    • 2008
  • 본 논문에서는 새로이 제안된 접합부를 가진 단층 래티스 돔의 비탄성 거동을 실험적으로 분석하였다. 구조적인 성능과 시공성을 모두 만족시키기 위해서 제안된 새로운 접합부를 적용하여 강관으로 구성된 스팬 7m의 축소 실험모델을 제작하였으며, 하중 전이장치를 이용하여 각 절점에 균일한 하중이 가력되는 정적 재하실험을 수행하였다. 최대 가력하중은 설계하중의 약 1.6배였으며, 일부 부재에서 압축 항복점을 넘어 비탄성 좌굴이 발생하였다. 좌굴 발생 이후에는 가력장치가 허용할 수 있는 변위까지 실험을 수행하였으며, 실험을 통해서 구해진 래티스 돔의 거동을 구조설계의 관점에서 분석하였다.

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단일발광층을 이용한 백색 OLED (White OLEDs with a Single Emissive Layer)

  • 추혜용;이정익;양용석;오지영;박상희;김미경;황치선;정병준;심홍구;장진
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2004년도 춘계학술대회 논문집 디스플레이 광소자분야
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    • pp.43-46
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    • 2004
  • We demonstrated efficient white light emitting OLEDs with a single emissive layer structure, which was blue-emitting 1,4-bis[2,2-diphenylvinyl]biphenyl (DPVBi) doped with blue luminescent amino-substituted distyrylarylene amine (DSA-amine) and red luminescent [2,6-bis[2-[5-(dibutylamino) phenyl]vinyl]-4H -pyran-4-ylidene]propanedinitrile (DADB). Through the optimization of the device structure, the white light emission with full visible spectral range was obtained. Its CIE color coordinates was (0.32,0.42) at 10 $mA/cm^2$ and the external quantum efficiency, the luminance efficiency and the luminance yield were 3.7 %, 3.3 lm/W and 9.0 cd/A, respectively.

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Bottom Collector와 단일 금속층 구조로 설계된 SiGe HBT의 전기적 특성 (Structure and Electrical Properties of SiGe HBTs Designed with Bottom Collector and Single Metal Contact)

  • 최아람;최상식;윤석남;김상훈;서형기;심규환
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2007년도 하계학술대회 논문집 Vol.8
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    • pp.187-187
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    • 2007
  • This paper presents the electrical properties of SiGe HBTs designed with bottom collector and single metal layer structure for RF power amplifier. Base layer was formed with graded-SiGe/Si structures and the collector place to the bottom of the device. Bottom collector and single metal layer structures could significantly simplify the fabrication process. We studied about the influence of SiGe base thickness, number of emitter fingers and temperature dependence (< $200^{\circ}C$) on electrical properties. The feasible application in 1~2GHz frequency from measured data $BV_{CEO}$ ~10V, $f_r$~14 GHz, ${\beta\simeq}110$, NF~1 dB using packaged SiGe HBTs. We will discuss the temperature dependent current flow through the e-b, b-c junctions to understand stability and performance of the device.

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다공성 바이폴라 사용 단위전지 성능 특성 (Performance Characteristics of Porous Plate Single Cell For PAFC)

  • 김창수;전영갑;송락현;최병우;신동열;최수현
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1996년도 하계학술대회 논문집 C
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    • pp.1707-1709
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    • 1996
  • For the improvement of the performance and life time of phosphoric acid fuel cell, the management of electrolyte in the electrocatalyst layer and electrolyte matrix in the cell structure is very important. Porous bipolar pinto structure, that is known as an advanced type, is generally used for the storage of electrolyte in the cell. In this paper, the single cell was made of the electrode by coating directly electrocatalyst layer on porous bipolar plate. The single cell showed $186\;mA/cm^2$ at 0.6V. This performance is similar to the performance of the conventional nonporous plate single cell. The technology of porous plate single cell could be directly used to the fabrication of stack in order to improve the performance and life time of phosphoric acid fuel cell.

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