• Journal of Information Display
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• 제2권1호
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• pp.24-33
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• 2001

The characteristics of the reset and the address discharges of an alternating current Plasma Display Panel (ac PDP) were studied using 2-dimensional numerical discharge cell simulation. We investigated the wall charge variations during the reset discharge adopting ramping reset pulse and the subsequent addressing discharge. The roles of the ramping reset scheme can be divided into two stages, each electrode gathers wall charges during ramping-up of the initial stage and the built-up wall charges are lost during ramping-down of the later stage. Address discharge does not only change the wall charge distributions on the address and the scan electrodes but also on the sustain electrode. The increase in the wall charges on the sustain electrode was observed with the variation of the applied voltage to the sustain electrode during the address period. The increase of the applied voltage to the sustain electrode during the address period is expected to induce the decrease of the sustain voltage during the display period.

• Korean Journal of Chemical Engineering
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• 제35권12호
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• pp.2452-2463
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• 2018

Surface treatment of sol-gel bioglass is required to increase its biomedical applications. In this study, a dielectric barrier discharge (DBD) plasma treatment in atmospheric pressure was performed on the surface of [$SiO_2-CaO-P_2O_5-B_2O_3$] sol-gel derived glass. The obtained bioglass was treated by plasma using discharge current 12 mA with an exposure period for 30 min. The type of discharge can be characterized by measuring the discharge current and applied potential waveform and the power dissipation. Apatite formation on the surface of the DBD-treated and untreated samples after soaking in simulated body fluid (SBF) at $37^{\circ}C$ is characterized by Fourier transform infrared spectroscopy (FTIR), X-Ray diffraction (XRD), inductively coupled plasma (ICP-OES) and scanning electron microscopy coupled with energy dispersive spectroscopy (SEM/EDS). We observed a marked increase in the amount of apatite deposited on the surface of the treated plasma samples than those of the untreated ones, indicating that DBD plasma treatment is an efficient method and capable of modifying the surface of glass beside effectively transforming it into highly bioactive materials.

• Journal of Power Electronics
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• 제6권4호
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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.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2003년도 춘계전력전자학술대회 논문집(2)
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• pp.755-760
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• 2003

A novel current-fed energy-recovery sustaining driver (CFERSD) for a PDP is proposed in this paper. Its main idea is to recover the energy stored in the PDP or to inject the input source energy to the PDP by using the current source built-up in the energy recovery inductor. This method provides zero-voltage-switching (ZVS) of all main power switches, the reduction of EMI, and more improved operational voltage margins with the aid of the discharge current compensation. In addition, since the current flowing through the energy recovery inductor can compensate the plasma discharge current flowing through the conducting power switches, the current stress through all main power switches can be considerably reduced. Furthermore, it features a low conduction loss and fast transient time. Operations, features and design considerations are presented and verified experimentally on a 1020X106mm sized PDP, 50kHz-switching frequency, and sustaining voltage 140V based prototype.

• 한국환경과학회지
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• 제21권6호
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• pp.739-747
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• 2012

Due to the difficulties for measuring flood discharge in the dangerous field conditions, conventional instruments with relatively low accuracy such as float still have been widely utilized for the field survey. It is also limited to use simple stage-discharge relationship for assessment of the flood discharge, since the stage-discharge relationship during the flood becomes complicated loop shape. In recent years, various non-intrusive velocity measurement techniques such as electromagnetic wave or surface images have been developed, which is quite adequate for the flood discharge measurements. However, these new non-intrusive techniques have little tested in the flood condition, though they promised efficiency and accuracy. Throughout the field observations, we evaluated the validity of these techniques by comparing discharge and velocity measurements acquired concurrently during the flood in a mountain stream. As a result, the flood discharge measurements between electromagnetic wave and surface image processing techniques showed high positive relationship, but velocities did not matched very well particularly for the high current speed more 3 m/s. Therefore, it should be noted here that special cares are required when the velocity measurements by those two different techniques are used, for instance, for the validation of the numerical models. In addition, authors assured that, for the more accurate flood discharge measurements, velocity observation as well as stage height is strongly necessary owing that the unsteady flow occurs during the flood.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2001년도 하계학술대회 논문집
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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.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1998년도 추계학술대회 논문집 학회본부 C
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• pp.841-843
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• 1998

The fiat fluorescent lamp(FFL) can be used to the LCD bat]flighting. In order to evaluate the discharge characteristics of FFL firing voltage, discharge current, luminance and CIE chromaticity with frequency were measured. The experimental results show that firing voltage decreased with increasing the frequency, discharge current increased with increasing the frequency. Luminance of FFL using Xe gas shown $2700\;cd/m^2$ in 700V rms, 80 kHz.

• 한국수소및신에너지학회논문집
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• 제7권1호
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• pp.3-9
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• 1996

금속과 물의 혼합체에 전기방전을 야기시켜 수소를 제조하는 방법은 필요시에 즉시 수소를 제조할 수 있는 유용한 방법이다. 그러나 이 방법이 실제로 이용될 수 있기 위해서는 입력되는 전기에너지당 물과의 반응을 일으키는 금속의 양이 가능한한 큰 값을 가져야 한다. 이러한 에너지 효율을 높이기 위해서는 약한 전기방전이 화학반응을 지속시킬 수 있어야 된다. 이러한 효율에 직결되는 실험변수중에서 방전 전압-전류 곡선을 측정하여 토의하였다.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2003년도 제5회 영호남 학술대회 논문집
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• pp.67-71
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• 2003

One of the most important problems in ADS method is that the method has too long addressing period, The addressing time can be defined as the sum of the discharge time lag and the duration of discharge current. If the addressing time increases, the sustaining period for display image should be decreased. As a result, the luminance of the PDP decreases. Therefore, the discharge time lag and duration of discharge current should be decreased in order to reduce the addressing time. In this paper, in order to improve addressing time, relationships between addressing time and cell structure in AC PDP was studied

• 대한전기학회:학술대회논문집
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• 대한전기학회 1994년도 하계학술대회 논문집 C
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• pp.1533-1535
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• 1994

The Monte-Carlo simulation was used to define the physical mechanisms of the initiation phase of pseudo-spark discharge. The pseudo-spark discharge employing the hollow cathode geometry is accompanied by very fast current rising and intense charged particle beams. In this model, time-dependent continuity equation for the electrons and ions were solved consistently with Poisson's equation for the electric field in a two-dimensional, sysmmetrically cylinderical geometry. From the simulation, a sequence of physical mechanisms that cause the rapid current rise associated with the onset of pseudo-spark discharge mode were identified.