• Journal of Electrochemical Science and Technology
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• v.8 no.3
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• pp.197-205
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• 2017

Lead dioxide thin films were electrodeposited on nickel substrate from acidic lead nitrate solution. Current efficiency and thickness measurements, cyclic voltammetry, AFM, SEM, and X-ray diffraction experiments were conducted on $PbO_2$ surface to elucidate the effect of lead nitrate concentration, current density, temperature on the morphology, chemical behavior, and crystal structure. Experimental results showed that deposition efficiency was affected by the current density and solution concentration. The film thickness was independent of current density when deposition from high $Pb(NO_3)_2$ concentration, while it decreased for low concentration and high current density deposition. On the other hand, deposition temperature had negative effect on current efficiency more for lower current density deposition. Cyclic voltammetric study revealed that comparatively more ${\beta}-PbO_2$ produced compact deposits when deposition was carried out from high $Pb(NO_3)_2$ concentration. Such compact films gave lower charge discharge current density during cycling. SEM and AFM studies showed that deposition of regular-size sharp-edge grains occurred for all deposition conditions. The grain size for high temperature and low concentration $Pb(NO_3)_2$ deposition was bigger than from low temperature and high concentration deposition conditions. While cycling converted all grains into loosely adhered flappy deposit with numerous pores. X-ray diffraction measurement indicates that high concentration, high temperature, and high current density favored ${\beta}-PbO_2$ deposition while ${\alpha}-PbO_2$ converted to ${\beta}-PbO_2$ together with some unconverted $PbSO_4$ during cycling in $H_2SO_4$.

• Proceedings of the KIPE Conference
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• 2007.07a
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• pp.381-383
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• 2007

Charge-pump high voltage inverter for Plasma backlight with CIM(Current Injection Method) is proposed in this paper. Adoption of ERC is a new attempt in high voltage inverter so that it is not only energy recovery but also improvement of discharge stability and system unstability which is interrupted by noise. Using a charge-pump technique enables low voltage switches to be usable, the cost can be reduce. CIM is adopted to achieve high speed energy recovery in proposed circuit. Operations of the proposed circuit are analyzed for each mode. The proposed circuit is verified to be applicable on a 32 inch plasma backlight panel by experimental results.

• 한국정보디스플레이학회:학술대회논문집
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• 2002.08a
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• pp.211-214
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• 2002

We present gray scale implementation method based on QMA driving technique. We clarified the mechanism of wall charge quantization through discharge current measurement. We used three wall charge states to implement gray scale. The cells would be one of fully-ON, half-On, and OFF states. We built a five sub-fields 243 level gray scale with sustain pulse count of 2, 6, 18, 54, and 162.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1997.11a
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• pp.144-148
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• 1997

We synthesized polyaniline films electrochemically under constant current conditions, which exhibited electric conductivity as high as 100 S/cm. By charge and discharge cycling of polyaniline films, we obtained specific discharge capacity as high as 195 mAH/g using HSO$_4$- doped polyaniline. For the polyaniline synthesized using H$_2$SO$_4$ and HClO$_4$ composite electrolyte. we also obtained specific discharge capacity as high as 134 mAHg which rivals inorganic electro- active materials.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2000.07a
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• pp.507-510
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• 2000

The purpose of this study is to research and developV$_2$O$_{5}$-SP270 composite electrode for supercapacitor. Property of an electrical double layer capacitor depend both on the technique used to prepare the electrode and on the current collector structure. The study is to research that V$_2$O$_{5}$-carbon composite electrode for supercapacitor with different voltage range. Suprcapacitor cell of V$_2$O$_{5}$-SP270 composite electrode with 25PVDFLiC1O$_4$PC$_{10}$ polymer electrolyte bring out good capacitor performance below 3V. The discharge capacitance of SP270 in 1st cycles was 13F/g at 0.1mA/cm$^2$, 3V. We performed cycle voltammogram, charge/discharge property.y.rty.y.

• 한국정보디스플레이학회:학술대회논문집
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• 2004.08a
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• pp.529-532
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• 2004

The spatio-temporal variation of Infra Red(IR) emission images were obtained from a real 3-dimensional discharge space of a surface discharge type, alternating current plasma display panel(AC PDP) cell with the Ne-Xe(4%) 400Torr gas mixture. IR emissions were observed in each period of the ADS(Address and Display Separation) driving scheme with ramp initializing waveform using an images intensified charge coupled device(ICCD) camera. The roles of each electrode were identified and it was compared with the results of the discharge simulation and of the wall charge distributions measured by the electro-optic technique.

• Journal of Power Electronics
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• v.11 no.1
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• pp.1-9
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• 2011

This paper describes a two quadrant bidirectional soft switching converter for ultra capacitor interface circuits. The total efficiency of the energy storage system in terms of size and cost can be increased by a combination of batteries and ultra capacitors. The required system energy is provided by a battery, while an ultra capacitor is used at high load power pulses. The ultra capacitor voltage changes during charge and discharge modes, therefore an interface circuit is required between the ultra capacitor and the battery. This interface circuit must have good efficiency while providing bidirectional power conversion to capture energy from regenerative braking, downhill driving and the protecting ultra capacitor from immediate discharge. In this paper a fully soft switched two quadrant bidirectional soft switching converter for ultra capacitor interface circuits is introduced and the elements of the converter are reduced considerably. In this paper, zero voltage transient (ZVT) and zero current transient (ZCT) techniques are applied to increase efficiency. The proposed converter acts as a ZCT Buck to charge the ultra capacitor. On the other hand, it acts as a ZVT Boost to discharge the ultra capacitor. A laboratory prototype converter is designed and realized for hybrid vehicle applications. The experimental results presented confirm the theoretical and simulation results.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2001.07a
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• pp.1043-1046
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• 2001

In this study, characteristics of LPB having gold anode fabricated by sputtering methode were analyzed. As results, The 1st efficiency and the impedance characteristics of LPB decreased with increased gold coated on anode and current collector. But the rate characteristics and charge-discharge cycling characteristics increased with increased gold coated on anode and current collector. During 2C discharge of the rate characteristics test, the rate characteristics of LPB without gold coated and the rate characteristics of LPB with gold coated in twice were 159mAh/g and 189mAh/g, respectively. The discharge capacity was gradually degreased with the discharge cycling to about 20th cycles. But LPB with gold coated in twice was stabilized than LPB without gold coated.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.20 no.5
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• pp.49-56
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• 2006

The bi-directional converter interfaces the low voltage battery to the inverter do link of FC generation system. When power flows from the low voltage side(battery: 48[V]) to the high voltage side(dc link: 380[V]), the circuit works in discharge mode (boost) to power the high voltage side load; otherwise, it works in charge mode (buck) to charge the low voltage side battery. In this paper, the 1.5[kW] active clamp current-fed full bridge converter employing MOSFETs is operated to discharge the battery whereas a voltage-fed half bridge converter employing IGBTs is operated to charge the battery.

• Journal of Power Electronics
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• v.6 no.4
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• pp.298-306
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• 2006

A high efficiency and low cost sustain driver for a plasma display panel (PDP) utilizing a current pumping method is proposed. The main concept of the proposed circuit is using the current source to charge and discharge the panel. As a result, all power switches can achieve zero voltage switching (ZVS) and every auxiliary switch can also achieve zero current switching (ZCS). Since the inductor current can compensate for the discharge current, the current stress of all the power switches can be reduced considerably. Furthermore, it has features such as a simpler structure, less mass, lower cost, and lower electromagnetic interference than in previous circuits.