• Title/Summary/Keyword: layered structure

Search Result 1,144, Processing Time 0.026 seconds

Performance Analysis of Layered and Blended Organic Light-Emitting Diodes

  • Park, Jong-Woon;Yim, Yeon-Chan;Heo, Gi-Seok;Kim, Tae-Won;Lee, Jong-Ho;Park, Seung-Hwan
    • 한국정보디스플레이학회:학술대회논문집
    • /
    • 2008.10a
    • /
    • pp.424-427
    • /
    • 2008
  • We make performance simulations of three different organic light-emitting diodes (OLEDs), one of which is based on a conventional layered structure and the others on a blended structure where an emitting layer (EML) is either uniformly or stepwise mixed with an electron transport layer (ETL), Tris-(8-hydroxyquinoline) aluminum ($Alq_3$).

  • PDF

Dynamic Characteristics and Compressive Stress of Multi-Layered Structure (적층 구조물의 압축응력과 동적특성)

  • Shon, Ho-Woong;Lee, Sung-Min
    • Journal of the Korean Geophysical Society
    • /
    • v.9 no.1
    • /
    • pp.63-71
    • /
    • 2006
  • When surveying the cultural heritages especially in the case of stone structures, preserving their originalstate is of primary importance. For the effective assessment of survey results of stone structure, thedynamic characteristics of that system should be considered. Dynamic characteristics of stone masonry structures depend on several factors such as coefficients of friction, contact conditions, and number of layers of bonding stones. These factors can be estimated by using the dynamic analysis results. This paper describes a method for natural frequency determination of traditional stone arch bridge subjected to compressive force. For this purpose, multi-layered granite brick models of for arch bridge were made and fundamental frequencies corresponding increasing axial forces were measured.

  • PDF

Degradation and Rheological Properties of Biodegradable Nanocomposites Prepared by Melt Intercalation Method

  • Lee, Su-Kyong;Seong, Dong-Gi;Youn, Jae-Ryoun
    • Fibers and Polymers
    • /
    • v.6 no.4
    • /
    • pp.289-296
    • /
    • 2005
  • Biodegradable nanocomposites were prepared by mixing a polymer resin and layered silicates by the melt intercalation method. Internal structure of the nanocomposite was characterized by using the small angle X-ray scattering (SAXS) and transmission electron microscope (TEM). Nanocomposites having exfoliated and intercalated structures were obtained by employing two different organically modified nanoclays. Rheological properties in shear and extensional flows and biodegradability of nanocomposites were measured. In shear flow, shear thinning behavior and increased storage modulus were observed as the clay loading increased. In extensional flow, strain hardening behavior was observed in well dispersed system. Nanocomposites with the exfoliated structure had better biodegradability than nanocomposites with the intercalated structure or pure polymer.

Numerical Study of Double Diffusive Convection of a Stratified Fluid in an Annulus Due to Lateral Heating (환형밀폐용기내 성층화된 유체의 옆면가열에 의한 이중확산대류에 관한 수치해석)

  • 강신형;전창덕;이진호
    • Transactions of the Korean Society of Mechanical Engineers
    • /
    • v.19 no.7
    • /
    • pp.1720-1730
    • /
    • 1995
  • Finite-difference analysis was conducted to study the natural convection of a stably stratified salt-water solution in an annulus due to lateral heating. The main purpose of this study is to examine in detail the multi-layered flow structure. Calculation was thus made for R $a_{\eta}$=2*10$^{5}$ and 6.5*10$^{5}$ . Formation of layered flow structure, merging process of layers, the corresponding temperature and concentration distributions, Nusselt number variations with time are examined. Numerical results show that in each layer, the temperature profile looks 'S`-shaped and the concentration profile is uniform due to the convective mixing. The formation of the roll and the layer is governed by natural convection due to the temperature gradient and the merging process of the layer by diffusion of the concentration.ation.

Fabrication and characterization of SILO isolation structure (SILO 구조의 제작 방법과 소자 분리 특성)

  • Choi, Soo-Han;Jang, Tae-Kyong;Kim, Byeong-Yeol
    • Proceedings of the KIEE Conference
    • /
    • 1988.07a
    • /
    • pp.328-331
    • /
    • 1988
  • Sealed Interface Local Oxidation (SILO) technology has been investigated using a nitride/oxide/nitride three-layered sandwich structure. P-type silicon substrate was either nitrided by rapid thermal processing, or silicon nitride was deposited by LPCVD method. A three-layered sandwich structure was patterned either by reactive ion etch (RIE) mode or by plasma mode. Sacrificial oxidation conditions were also varied. Physical characterization such as cross-section analysis of field oxide, and electrical characterization such as gate oxide integrity, junction leakage and transistor behavior were carried out. It was found that bird's beak was nearly zero or below 0.1um, and the junction leakages in plasma mode were low compared to devices of the same geometry patterned in RIE mode, and gate oxide integrity and transistor behavior were comparable. Conclusively, SILO process is compatible with conventional local oxidation process.

  • PDF

Synthesis of a Series of Long Chain Lamellar Inorganic/Organic Iron(II) Alkylsulfonate Hydrates

  • Park, Seong-Hun
    • Journal of Integrative Natural Science
    • /
    • v.1 no.2
    • /
    • pp.76-78
    • /
    • 2008
  • A series of the long-chain iron(II) alkylsulfonate hydrates were synthesized via self-assembly of surfactant alkyl chains in aqueous medium. Reaction of iron(II) salts with n-alkylsulfonate yields lamellar $Fe(CnH2n+1SO3)2{\cdot}4H_2O$. These compounds show a layered structure, as determined by XRD, consisting of alternating organic alkylsulfonate layers and inorganic iron(II) hydrate layers, with interlayer distances of upto 3.2 nm. This lamellar structure may be attributed to the amphiphilic nature of the surfactants, mediating the coordination and H-bionding interactions, and the hydrophobic alkyl chains. An alkyl chain packing of present system are differ from those of similar Cu(II) series, which are attributed from the size of hydrated metal(II) ions.

  • PDF

Effective Compression Technique of Multi-view Image expressed by Layered Depth Image (계층적 깊이 영상으로 표현된 다시점 영상의 효과적인 압축 기술)

  • Jee, Inn-Ho
    • The Journal of the Institute of Internet, Broadcasting and Communication
    • /
    • v.14 no.4
    • /
    • pp.29-37
    • /
    • 2014
  • Since multi-view video exists a number of camera color image and depth image, it has a huge of data. Thus, a new compression technique is indispensable for reducing this data. Recently, the effective compression encoding technique for multi-view video that used in layered depth image concepts is a remarkable. This method uses several view point of depth information and warping function, synthesizes multi-view color and depth image, becomes one data structure. In this paper we use actual distance for solving overlap in layered depth image that reduce required data for reconstructing in color-based transform. In experimental results, we confirmed high compression performance and good quality of reconstructed image.

The preparation and Characterization of Bismuth Layered Ferroelectric Thin Films by Sol-Gel Process (솔-젤법을 이용한 Bismuth Layered Structure를 가진 강유전성 박막의 제조 및 특성평가에 관한 연구)

  • 주진경;송석표;김병호
    • Journal of the Korean Ceramic Society
    • /
    • v.35 no.9
    • /
    • pp.945-952
    • /
    • 1998
  • Ferroelectric Sr0.8Bi2.4Ta2O9 stock solutions were prepared by MOD(Metaloganic Decompostion) process. The phase transformation for the layered perovskite of the SBT thin films by changing RTA(Rapid her-mal Annealing) temperatuer from 700$^{\circ}C$to 780$^{\circ}C$ were observed using XRD and SEM. Layered perovskite phase began to appear above 740$^{\circ}C$ and then SBT thin films were annealed at 800$^{\circ}C$ for 1hr for its com-plete crystallization. The specimens showed well shaped hysteresis curves without post annealing that car-ried out after deposition of Pt top electrode. The SBT thin films showed the asymmetric ferroelectric pro-perties. It was confirmed that the properties were caused by interface effect to SBT and electrode by leak-age current density measurement and asymmetric properties reduced by post annealing. At post annealing temperature of 800$^{\circ}C$ remanant polarization values (2Pr) were 6.7 9 ${\mu}$C/cm2 and those of leakage current densities were 3.73${\times}$10-7 1.32${\times}$10-6 A/cm2 at 3, 5V respectively. Also bismuth bonding types of SBT thin film surface were observed by XPS.

  • PDF

The Warpage Phenomena of Electrolyte Layer During the Sintering Process in the Layered Planar SOFC Module (적층 평판형 SOFC 모듈에서 소결 시 전해질 층의 휨 현상)

  • Oh, Min-Wook;Gu, Sin-Il;Shin, Hyo-Soon;Yeo, Dong-Hun
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
    • /
    • v.25 no.3
    • /
    • pp.241-246
    • /
    • 2012
  • A layered planer SOFC module was designed from planar-type SOFC. It was prepared by multi-layered ceramic technology. To form the cathode and the anode in the layered structure, reliable channels should be made on the both side of electrolyte perpendicularly. However, monolithic SOFC using multi-layered ceramic technology hasn't been studied another group, and the warpage of electrolyte in the channel, also, hasn't been studied, when electrode is printed on the electrolyte. In this study, the channels are prepared with electrode printing, and their warpage are evaluated. In the case of YSZ without electrode, the warpages are nothing in the limit of measurement using optical microscope. The warpage of 'YSZ-NiO printed' increases than that of 'NiO printed', and also, the case of 'double electrode printed' is similar to 'YSZ-NiO printed'. It is thought that, in the printed electrolyte, the warpage is related to the difference of the sintering behavior of each material.