• 제목/요약/키워드: Transport layer

검색결과 1,250건 처리시간 0.027초

Efficiency enhancement mechanism in organic light-emitting devices with multiple heterostructures acting as a hole transport layer

  • Han, S.M.;Lee, K.S.;Choo, D.C.;Kim, T.W.;Seo, J.H.;Kim, Y.K.
    • 한국정보디스플레이학회:학술대회논문집
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    • 한국정보디스플레이학회 2007년도 7th International Meeting on Information Display 제7권2호
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    • pp.1451-1453
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    • 2007
  • The electrical and the optical properties of organic light-emitting devices (OLEDs) with or without multiple heterostructures acting as a hole transport layer were investigated. The efficiency enhancement mechanism in the OLEDs with multiple heterostructures is described on the basis of the electrical and the optical results.

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Numerical Analysis of Impurity Transport Along Magnetic Field Lines in Tokamak Scrape-011 Layer

  • Chung, Tae-Kyun;Hong, Sang-Hee
    • Nuclear Engineering and Technology
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    • 제30권1호
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    • pp.17-25
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    • 1998
  • Transport of carbon and boron impurity ions parallel to magnetic field lines in the tokamak SOL (scrape-off layer) is numerically investigated for a one-dimensional steady state. The spatial distributions of density and velocity of the impurity ions in a steady state are calculated by finite difference method for a single-fluid model. The calculated results show that among forces acting on SOL particles thermal force produced tv plasma temperature gradient is a principal force determining the feature of impurity distribution profiles in the tokamak edge. However, strong collisional friction forces appearing dominant in front of the diverter plate restrain impurity ion flows due to temperature gradients from moving toward the midplane. Consequently, the stagnation point develops in the impurity flow by these two forces near the diverter region, in which ion flows change their directions. Impurity ions turn out to be accumulated at the stagnation points, where peaked profiles of highly-ionized state ions are relatively predominant over those of low-ionized state ions.

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Enhancement of the efficiency in green organic light-emitting devices utilizing multiple heterostructures acting as a hole transport layer

  • Choo, D.C.;Lee, D.U.;Yoon, Y.B.;Kim, T.W.;Kim, J.H.;Seo, J.H.;Kim, Y.K.
    • 한국정보디스플레이학회:학술대회논문집
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    • 한국정보디스플레이학회 2006년도 6th International Meeting on Information Display
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    • pp.1024-1027
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    • 2006
  • The electrical and the optical properties of organic light-emitting devices (OLEDs), with and without various kinds of multiple heterostructures were investigated. The efficiency in green OLEDs were significantly enhanced by the structure of the multiple heterostructures acting as a hole transport layer (HTL) rather than by the number of periods. These results indicate that highly efficient green OLEDs utilizing multiple heterostructures acting as a HTL can be fabricated.

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Effect of the location of dye-doped layers on the electroluminescence characteristics of white organic emitting

  • Bang, H.S.;Kwon, D.S.;Lee, C.H.
    • 한국정보디스플레이학회:학술대회논문집
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    • 한국정보디스플레이학회 2006년도 6th International Meeting on Information Display
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    • pp.1050-1053
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    • 2006
  • We fabricated white organic light emitting diodes consisting of three emitting layers of red-emitting DCM2 doped ${\alpha}-NPD$, blue-emitting DPVBi and green-emitting C545T doped Alq3. By optimizing the thickness of the hole-transport layer of ${\alpha}-NPD$ and the electron-transport layer of Alq3, efficient white OLEDs were obtained with a luminous efficiency of 4.40lm/W at luminance of $1000cd/m^2$, and a max-imum luminance of $51,939cd/m^2$

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Solution-processed electrophosphorescent devices with a thin fluoropolymer at the hole transport interfacial layer

  • Park, Jae-Kyun;Hwang, Gyoung-Seok;Lee, Tae-Woo;Chin, Byung-Doo
    • Journal of Information Display
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    • 제12권4호
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    • pp.223-227
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    • 2011
  • Electrophosphorescent devices with ionomer-type hole transport layers were investigated. On top of the 3,4-ethylenedioxy thiophene:poly(4-styrene sulfonate) [PEDOT:PSS] structures, fluoropolymer interfacial layers (FPIs) with different side chain lengths were introduced. Both for the PEDOT:PSS/FPI (layered) and PEDOT:PSS (mixed) structures with soluble phosphorescent emitters, the short-side-chain FPIs showed higher efficiency. The difference in the electrical properties of the two FPIs for bipolar (light-emitting) devices was not clear, but the hole-only device clearly showed the favored hole injection at the PEDOT:PSS/FPI structure with a shorter side chain, a copolymer of tetrafluoroethylene and sulfonyl fluoride vinyl ether.

Salt and Sand Transport from Aral Sea Basin

  • 이귀주
    • 한국해양공학회지
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    • 제19권3호
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    • pp.47-53
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    • 2005
  • Model for dust and salt transportation from the dried bottom of the Aral Sea is suggested. Theoretical analysis is based on the turbulent diffusion equation for the averaged function of passive impurity concentration. One-layer model of the atmospheric boundary layer is assumed. Impurity precipitation rates are calculated as the functions of the particle size and the distance source of particles. Analytical solutions for the point and two-dimensional sources of impurities are found. Model calculations for salt and sand transport from the Aral Sea basin are made on the basis of 2D source model with a constant intensity.

Recent Progress in Flexible Perovskite Solar Cell Development

  • Ren, Xiaodong;Jung, Hyun Suk
    • 한국세라믹학회지
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    • 제55권4호
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    • pp.325-336
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    • 2018
  • Perovskite solar cells (PSCs) are a new class of photovoltaic devices, which have attracted significant attention due to their remarkable optoelectrical properties, including high absorption coefficients, high carrier mobilities, long carrier diffusion lengths, tunable bandgaps, low cost, and facile fabrication. PSCs have reached efficiencies of 22.70% and 18.36% on rigid fluorine-doped tin oxide and poly(ethylene terephthalate) substrates, respectively; these are comparable to those of single-crystal silicon and copper-indium-gallium-selenium solar cells. Over the past eight years, the photo conversion efficiency of PSCs has been significantly improved by device-architecture adjustments, and absorber and electron/hole transport layer optimization. Each layer is important for the performance of PSCs; hence, we discuss achievements in flexible perovskite solar cells (FPSCs), covering electron/hole-transport materials, electrode materials. We give a comprehensive overview of FPSCs and put forward suggestions for their further development.

Second Harmonic Generation study on the transport dynamics of small molecules across liposome bilayers

  • Kim, Joon-Heon;Kim, Mahn-Won
    • 한국생물물리학회:학술대회논문집
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    • 한국생물물리학회 2003년도 정기총회 및 학술발표회
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    • pp.79-79
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    • 2003
  • SHG (Second harmonic generation) can be used to probe the surface of centrosymmetric particles suspended in bulk isotropic solution, because it is forbidden in centrosymmetric media under the dipole approximation. Using this technique, we can study the transport dynamics of small organic dye molecules across liposome bilayers. Because molecules adsorbed on the outer layer are in opposite direction with that on the inner layer by symmetry, the SH field is proportional to the difference between the number density of dye molecules on both sides of the bilayer, and the time dependence of the SH intensity is related to the time constant of the molecular transportation of dye molecules across liposome bilayers.

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Game Traffic Classification Using Statistical Characteristics at the Transport Layer

  • Han, Young-Tae;Park, Hong-Shik
    • ETRI Journal
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    • 제32권1호
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    • pp.22-32
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    • 2010
  • The pervasive game environments have activated explosive growth of the Internet over recent decades. Thus, understanding Internet traffic characteristics and precise classification have become important issues in network management, resource provisioning, and game application development. Naturally, much attention has been given to analyzing and modeling game traffic. Little research, however, has been undertaken on the classification of game traffic. In this paper, we perform an interpretive traffic analysis of popular game applications at the transport layer and propose a new classification method based on a simple decision tree, called an alternative decision tree (ADT), which utilizes the statistical traffic characteristics of game applications. Experimental results show that ADT precisely classifies game traffic from other application traffic types with limited traffic features and a small number of packets, while maintaining low complexity by utilizing a simple decision tree.

The Study of the Charge Transport on the Surface Layer of the Patterned Vertical Alignment(PVA) Mode

  • Choi, Nak-Cho;You, Jae-Yong;Jung, Ji-Young;Rhie, Kung-Won;Shin, Sung-Tae
    • 한국정보디스플레이학회:학술대회논문집
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    • 한국정보디스플레이학회 2007년도 7th International Meeting on Information Display 제7권1호
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    • pp.571-573
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    • 2007
  • It is known that the main source of the area image sticking is the ion charge adsorption on the alignment layer. We found out that the adsorption of the ion charge of the liquid crystal in the cell was physisorption, which takes place between all molecules on any surface providing the adsorption force is small.

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