• The Transactions of the Korean Institute of Electrical Engineers C
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• v.49 no.12
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• pp.673-678
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• 2000

The dielectric barrier discharge(DBD) is a common method to create a nonthermal plasma in which electrical energy is used to create electrons with a high average kinetic energy. The unique aspect of dielectric barrier discharges is the large array of short lifetime(10ns) silent discharges created over the surface of the dielectric. A silent discharge is generated when the applied voltage exceeds the breakdown voltage of the carrier gas creating a conduction path between the applied electrode and grounded electrode. As charge accumulates on the dielectric, the electric field is reduced below the breakdown field of the carrier gas and the silent discharge self terminates preventing the DBD cell from producing a thermal arc. In fact, the most significant application of dielectric barrier discharges is to generate ozone for contaminated water treatment. Therefore, experiments were perfomed at 1∼2[bar] pressure using a coaxial geometry single dielectric barrier discharge for ozone concentrations and energy densities. The main result show that the concentration and efficiency of ozone are influenced by gas nature, gas quantity, gas pressure, supplied voltage and frequency.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2001.07a
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• pp.783-786
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• 2001

Recently deep interests and attractions have been paid on the generation of ozone, which is widely used to remove bad smell and to clear water. Silent discharge is considered as one of the most effective methods to generator ozone. In this paper, silent discharge reactors were made, waich were filled with different dielectric materials, and some silent discharge charactistics were investigated experimantaiiy.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2002.07b
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• pp.904-907
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• 2002

In this study, the plasma-assisted $CO_2$ conversion characteristics were investigated in the streamer corona discharge and silent discharge reactors with dielectric of $Al_2O_3$, to improve the conversion efficiency $CO_2$. Some discharge characteristics of $CO_2$ as parameters of gap spacing and applied voltage frequency, in both corona and silent discharge reactor were also obtained. The maximum $CO_2$ conversion rate was 10.1 [%] under the 5.2 [W] of discharge power and 250 [Hz] of applied voltage frequency.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2001.07a
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• pp.1061-1064
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• 2001

Deep Interests have been paid on the application of non-thermal plasma technique to solve the environmental pollution problems. $CO_2$, is one of the severe pollutants which cause the acid rain and global warming. In this study, in order to improve the conversion efficiency of $CO_2$, the streamer corona discharge plasma and barrier discharge plasma reactors were made, and the conversion characteristics of $CO_2$by the corona discharge plasma and some discharge characteristics of these discharge chambers are studied experimentally.

• Journal of the Korean Society of Safety
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• v.17 no.3
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• pp.112-117
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• 2002

A comparative investigation of an experimental and a simulation of chemical kinetics for NOx removal from silent(dielectric-barrier) discharges is presented. Several types of dielectric-barrier discharges were implemented depending upon the configuration of electrodes. The simulation was based on an approximate mathematical model for plasma cleaning of waste gas. The influence of non-uniform distributions of species due to the production of primary active particles in the streamer channel was taken into account. A comparison of observed experimental to the calculated removal efficiency of NOx showed acceptable agreement.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2000.11a
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• pp.379-382
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• 2000

The characteristics of Xe discharge lamp(Mercuryless lamp) are described in this paper. In this paper, FFL is operated by sine wave and pulsed source. We apply V-Q Lissajous' figure for the discharge measurements of FFL which has the electrodes covered with dielectric. When FFL is operated by sine wave source, the characteristics are similar to DBD(Dielectric Barrier Discharge) and SD(Silent Discharge). And we compared the characteristics of FFL which is operated with sine wave and pulsed discharge by using V-Q Lissajous' figure method. When FFL is operated with pulsed, the discharge current flows after the applied voltage is risen. As the duty ratio increases the electric field becomes strong and much more xenon ions are produced. And the number of metastable xenon atoms seem to increase, therefore, the phosphor radiation after the cut off of voltage increases compared with the first peak of radiation. Consequently, the 172㎚ radiation becomes strong as the duty ratio increases.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1999.11a
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• pp.169-172
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• 1999

In this experimental study we Proposed the double dielectric barrier discharge (DDBD) reactor to produce as high an electric field as possible. The experiment are conducted for applied voltage from 15 to 20[tV], flow gas rage at 2[1/min] and pulse rate at 120[pulses/s] and 240[pulses/s]. SPD connection of DDBD which combine the surface discharge with the silence discharge was most effective to reduce the NOx. In the decomposition efficiency per watt, the low pulse rate gave hotter efficiency than that of the high pulse rate. However in DeNOx rate, the high pulse rate gave better performance than that of the low pulse rate. NOx removal rate increased with increasing the applied voltage in all reactors.

• Proceedings of the KIEE Conference
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• 1995.07c
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• pp.1410-1412
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• 1995

A high efficiency ozone generation using both of a electrode-edge discharge and a dielectric-harrier discharge from a modified silent type ozone generator has been proposed and studied for small scale applications. It is found that the output ozone concentration of the proposed generator depended greatly upon the air gap spacing and the applied power frequency and voltage on the ozone generation. The ozone generator showed higher ozone concentration than the same size of the ceramic type surface ozone generator(Masuda type one). And, it is found that the generator had a potential to be used as an ozone generator for small scale applications.

• Journal of the Institute of Electronics Engineers of Korea SC
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• v.45 no.5
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• pp.44-51
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• 2008

UV lamp systems have been used for cleaning of display panels of TFT LCD or Plasma Display Panel (PDP). However, the needs for high efficient cleaning and low cost made high voltage plasma cleaning techniques to be developed and to be improved. Dielectric-Barrier Discharges (DBDs), also referred to as barrier discharges or silent discharges have been exclusively related to ozone generation for a long time. In this paper, a 6kW high voltage plasma power supply system was developed for LCD cleaning. The 3-phase input voltage is rectified and then inverter system is used to make a high frequency pulse train, which is rectified after passing through a high-power transformer. Finally, hi-directional high voltage pulse switching circuits are used to generate the high voltage plasma. Some experimental results showed the usefulness of atmospheric plasma for LCD panel cleaning.

• Proceedings of the KIEE Conference
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• 2000.07e
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• pp.29-32
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• 2000

Ozone has been widely applied to many industrial fields because of its strong oxidation effects. Therefore, the studies have been progressed for the effective and high concentration of one generation. The silent or surface discharge have been mainly used for high concentration ozone generation until now. But these two types of ozone generators have shortcomings to be improved. In this study, the ozone generator which improved the shortcomings of above two type of ozone generators was proposed and manufactured for high concentration ozone generation. And the proposed ozone generator could generate the surface and barrier discharge simultaneously. For this purpose, a mesh type discharge electrodes were proposed and the experiments were fulfilled as a function of the widths and spacings of mesh electrodes and gap spacings between the dielectric barrier and mesh electrode. When the width of mesh electrode[WM] and spacing of mesh electrode[SM] are 0.3[mm] and 0.8[mm] respectively, the maximum ozone concentration of 2.96[vol%] was obtained at 5.6[kV], 830[mA], gap spacing (S)=0.65[mm].