• 대한전기학회:학술대회논문집
• /
• 대한전기학회 2009년도 제40회 하계학술대회
• /
• pp.1948.1_1949.1
• /
• 2009

본 논문에서는 냉음극관(CCFL) 구동 제어기 설계 법을 제안한다. 구성 되어지는 제어기는 오피 앰프와 저항 그리고 콘덴서로 이루어진 아날로그 제어기로서 비교적 간단한 구성으로 이루어지며 각 파라메터를 설계하기 위해 특성비 지정법(C.R.A)이 사용된다. 제안되어진 제어기 설계방법으로 실제 실험 제어기를 제작하여 제어기의 성능실험을 하였으며 매우 우수한 특성을 얻을 수 있었다.

• 한국정보디스플레이학회:학술대회논문집
• /
• 한국정보디스플레이학회 2006년도 6th International Meeting on Information Display
• /
• pp.984-986
• /
• 2006

We report efficient inverted transparent blue OLEDs (ITOED) with an hole injection layer prepared by co-evaporation of $WO_3$ with NPB, which achieved a total current efficiency of 10.7 cd/A at $20mA/cm^2$ with light emits from both ITO bottom cathode and Au top anode in about 3:1 ratio.

• 한국정보디스플레이학회:학술대회논문집
• /
• 한국정보디스플레이학회 2003년도 International Meeting on Information Display
• /
• pp.694-697
• /
• 2003

In applying LCD to TV application, one of the most significant factors to be improved is image sticking on the moving picture. LCD is different from CRT in the sense that it's continuous passive device, which holds images in entire frame period, while impulse type device generate image in very short time. To reduce image sticking problem related to hold type display mode, we made an experiment to drive LCD like CRT. We made articulate images by turn on-off backlight, and we realized the ratio of Back Light on-off time by adjusting between on time and off time for video signal input during 1 frame (16.7ms). Conventional CCFL (cold cathode fluorescent lamp) cannot follow fast on-off speed, so we evaluated new fluorescent substances of light source to improve residual light characteristic of CCFL. We realized articulate image generation similar to CRT by blinking drive. As a result, reduced image sticking phenomenon was validated by naked eye and response time measurement.

• 한국전기전자재료학회:학술대회논문집
• /
• 한국전기전자재료학회 2004년도 춘계학술대회 논문집 반도체 재료 센서 박막재료 전자세라믹스
• /
• pp.60-63
• /
• 2004

Recently, carbon nanotubes(CNTs) have been demonstrated to possess remarkable mechanical and electronic properties, in particular, for field emission applications. Its high aspect ratio and extremely small diameter, hollowness, together with high mechanical strength and high chemical stability, are advantages for use in field emitter. In this paper, we demonstrate electrical discharge properties from carbon nanotube cathode electrodes to use as an emitter electrode of vacuum gauges. Vertically aligned $2{\times}2mm^2$ CNT arrays on the silicon substrate were synthesized by the thermal CVD method on Fe catalytic metal, and a glass patterning by the sand blast method and the silicon/glass anodic bonding processes were applied to make samples with 2 electrodes. The field emission was examined under the vacuum range of $10^{-3}$ Torr.

• 한국표면공학회지
• /
• 제28권6호
• /
• pp.352-360
• /
• 1995

The effect of electrolysis conditions on the composition, the magnetic properties and the preferred orientation of Ni-Fe-Co alloy deposits was investigated using the sulfate-chloride bath paddle agitated. Cathode current efficiency increases with the current density, showing the different tendency of the variation from that of the Ni-Fe electrodeposits. The Co content of the deposits decreases with increasing current density, while the content of Ni and Fe is shown to be minimum or maximum at 3A/$dm^2$ respectively. The Ni/Fe ratio of the alloy deposits is lower than that of Ni-Fe deposits. The coercive force($H_c$) of the deposits increases with the Co content in deposit, showing the relatively low value in the range of 1.8~5.0Wt.% Co. The anisotropy field ($H_k$) of the deposits is higher than that of Ni-Fe alloy deposits, The preferred orientation of the deposits is generally (200), but the orientation factor(R) changes with both the increase of current density and the magnetic field applied during deposition.

• 한국정밀공학회:학술대회논문집
• /
• 한국정밀공학회 2006년도 춘계학술대회 논문집
• /
• pp.553-554
• /
• 2006

This paper presents the effects of different operating parameters on the performance of a proton exchange membrane (PEM) fuel cell by a three-dimensional computational fluid dynamics (CFD) model. The effects of different operating parameters on the performance of PEM fuel cell studied using pure hydrogen on the anode side and air on the cathode side. The various parameters are temperatures, pressures, humidification of the gas steams and various combinations of these parameters. In addition, geometrical and material parameters such as the gas diffusion layer (GDL) thickness and porosity as well as the ratio between the channel width and the land area were investigated.

• 한국전기전자재료학회:학술대회논문집
• /
• 한국전기전자재료학회 2002년도 추계학술대회 논문집 Vol.15
• /
• pp.444-447
• /
• 2002

The Jig cells are fabricated in the drying room, and consisted of elemental sulfur used as a cathode active material, lithium metal used as a anode material and 1M $LiCF_{3}SO_{3}$ dissolved in TG (Tetraglyme)/DIOX (1,3-Dioxolane) used as a electrolyte. The four kinds of electrolytes with different content of TG and DIOX are prepared. The electrochemical properties of the foregoing electrolytes-based lithium sulfur batteries are analyzed by AC impedance experiments. The conductivity of four different electrolytes is investigated. The conductivity of electrolyte [1M $LiCF_3SO_3$ dissolved in TG/DIOX (50:50, vol.)] is higher than that of other three kinds of electrolytes with different volume ratio (70:30, 30:70) and single solvent (TG).

• Bulletin of the Korean Chemical Society
• /
• 제35권10호
• /
• pp.2901-2905
• /
• 2014

The hierarchical-structured $LiFePO_4$ cathode materials were synthesized by one-step microwave synthesis, and their electrochemical properties were investigated. Addition of citric acid during the reaction lead to the formation of hierarchical structured $LiFePO_4$, which has both nano- and micron-characteristics advantageous for energy density and electrode fabrication. Adjusting the molar ratio of Fe to citric acid enhanced the electrochemical properties of $LiFePO_4$.

• 한국세라믹학회지
• /
• 제43권9호
• /
• pp.588-593
• /
• 2006

Spinel phase $LiMn_2O_4$ is of great interest as cathode materials for lithium-ion batteries. In this study, SHS (Self propagating High-temperature Synthesis) method to synthesize spinel $LiMn_2O_4$ directly from lithium nitrate, manganese oxide, manganese and sodium chloride were investigated. The influence of Li/Mn ratio, the heat-treated condition of product have been explored. The resultant $LiMn_2O_4$ synthesized under the optimum synthesis conditions shows perfect spinel structure, uniform particle size and excellent electrochemical performances.

• 한국표면공학회지
• /
• 제36권1호
• /
• pp.1-8
• /
• 2003

In general, the microstructure in thin films was known to evolve in similar manner according to the energy striking the condensing film at similar homologous temperature, Th for the materials of the same crystal structure. The fundamental factors affecting particle energy are a function of processing parameters such as working pressure, bias voltage, target/sputtering gas mass ratio, cathode shape, and substrate orientation. In this study, Al, Cu, Pt films of the same crystal structure of face centered cubic (FCC) have been prepared under various processing parameters. The influence of processing variables on the microstructures and residual stress states in the films has been studied.