• 한국추진공학회:학술대회논문집
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• 한국추진공학회 2012년도 제38회 춘계학술대회논문집
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• pp.527-528
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• 2012

플라즈마 유동제어를 통한 공기저항저감을 위해 DBD(Dielectric Barrier Discharge) 플라즈마 구동기를 설계하였고, 2D 시험모델의 풍동시험을 통해 항력저감을 측정하였다. 풍속이 없는 경우에는 유동박리 및 표면마찰저항이 존재하지 않으므로 플라즈마 유동제어를 통한 항력저감도 없었다. 2m/s의 풍속에서 유동박리제어를 통해 항력이 9.7%까지 감소됨을 확인하였으며, 풍속이 증가할수록 항력저감은 감소하였다.

• 한국전기전자재료학회논문지
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• 제24권1호
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• pp.57-63
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• 2011

Dielectric Barrier Discharge (DBD) reactor with sinsodual AC type of power supply is very widely adopted for its compact size and effective discharging mechanism to generate high density of ozone radicals. However, at the aspect of design on power supply, its optimal switching conditions and topology is achieved by empirical test. Therefore, throughout this paper, it is proposed a design method of DBD power supply to guarantee a maximum ozone yield rate in accordance with DBD reactor modification and impedance variation when rapid gas discharging in the DBD reactor is proceeded.

• Korean Chemical Engineering Research
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• 제45권2호
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• pp.183-189
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• 2007

대표적인 수은 발생원인 도시폐기물 소각로와 화력 발전소 등지에서 배출되는 원소수은($Hg^0$)은 산화수은($Hg^{2+}$) 및 입자상 수은($Hg^p$)과 달리 기존의 대기오염 방지시설로 제거하기 난해한 편이다. 그로 인해 원소수은의 효율적 제거에 대한 많은 연구가 진행중이며, 이 연구에서는 저온 플라즈마(non-thermal plasma)의 하나인 유전체 장벽 방전(dielectric barrier discharge: DBD) 공정을 이용하여 원소수은 산화에 관한 실험을 수행하였다. 실험 결과, 공기 상의 DBD 공정에서는 생성되는 산소 원자와 오존에 의해서 원소수은이 산화수은으로 전환됨을 알 수 있었으며, 원소수은의 산화율을 결정하는 주된 변수는 반응기에 주입되는 에너지 밀도임을 확인할 수 있었다.

• 한국대기환경학회지
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• 제18권3호
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• pp.173-182
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• 2002

We investigated the effects of operating variables, such as electrical. reactor and gas parameters on toluene removal and discharge property in the dielectric barrier discharge (DBD) process. The toluene removal was initiated with the energy transfer to the reactor by loading of voltages higher than the discharge onset value. The energy transfer and toluene removal increased with the applied voltage. Higher removal rate was observed with smooth surface electrode despite of lower energy transfer compared with the coarse electrode, because more uniform discharge can be obtained on smooth surface state. The decrease of dielectric material thickness enhanced the removal efficiency by increasing the discharge potential. The toluene removal efficiency decreased with the increase of the inlet concentration. The increase of gas retention time enhanced the removal efficiency by the increase of energy density. The oxygen and humidity contents seem to exert significant influences on the toluene removal by dominating the generation of electrons, ions, and radicals which are key factors in the removal mechanism.

• 한국수산과학회지
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• 제52권6호
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• pp.617-624
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• 2019

Dielectric barrier discharge (DBD) plasma is one of the promising next generation non-thermal technologies for food sterilization. The present study investigated the effects of DBD plasma on the reduction of most common food-borne pathogenic bacteria (Staphylococcus aureus, Bacillus cereus, Vibrio parahaemolyticus, Salmonella enterica) and sanitary indicative bacteria (Escherichia coli) in the suspension (initial inoculum of approx. 9 log CFU/mL). The bacterial counts were significantly (P<0.05) reduced with the increase in the treatment time (1-30 min) of DBD plasma in the suspension. The D-values (time for 90% reduction) of DBD plasma by first-order kinetics for S. aureus, B. cereus, V. parahaemolyticus, S. enterica, and E. coli were 17.76, 19.96, 32.89, 21.55, and 15.24 min, respectively (R²>0.90). These results specifically showed that 30 min of DBD plasma treatment in > 90% reduction of seafood-borne pathogenic and sanitary indicative bacteria. This suspension study may provide the basic data for use in seafood processing and distribution.

• Korean Chemical Engineering Research
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• 제57권3호
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• pp.432-437
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• 2019

유연전극 기반의 대기압 부유전극 유전체 장벽 방전 (floating electrode-dielectric barrier discharge, FE-DBD) 시스템을 개발하여 플라즈마 특성을 분석하였다. 유연한 파워전극(powered electrode)을 구성하는 유연유전체로 polytetrafluoroethylene (PTFE), polydiemethylsiloxane (PDMS), polyethylene terephthalate (PET)를 사용하여 플라즈마를 발생하였을 때 플라즈마의 광학적 세기와 전자온도는 파워전극에 인가하는 전압이 증가할수록 증가하였고, 전압이 일정할 때는 PTFE < PDMS < PET 순으로 증가하였다. 이는 유전체의 종류와 전압에 따른 축전용량의 변화로 설명할 수 있었고, 유연전극 기반의 대기압 FE-DBD 플라즈마의 특성은 유연한 파워전극을 구성하는 유전체와 파워전극에 인가되는 전압을 변화함으로써 조절될 수 있음을 의미한다. 유연전극 대기압 FE-DBD 시스템은 피부 곡면을 따라 플라즈마가 발생될 수 있으므로 플라즈마 메디신(plasma medicine)에 유용할 것으로 기대한다.

• KIEE International Transactions on Electrophysics and Applications
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• 제4C권3호
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• pp.101-105
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• 2004

The efficient power MOSFET inverter applied for a simple and low cost power supply is proposed for driving the dielectric barrier discharge (DBD) lamp load. For decades, the DBD phenomenon has been used for ozone gas production in industry. In this research, the ultraviolet and visible light sources utilizing the DBD lamp is considered as the load for solid-state high frequency power supply. It is found that the simple voltage-source single-ended quasi-resonant ZVS inverter with only one active power switch could effectively drive this load with the output power up to 700 W. The pulse density modulation based control scheme for the single-ended quasi-resonant ZVS inverter using a low voltage and high current power MOSFET switching device is proposed to provide a linear power regulation characteristic in the wide range 0-100％ of the full power as compared with the conventional control based Royer type parallel resonant inverter type power supplies.

• Korean Chemical Engineering Research
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• 제45권5호
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• pp.455-459
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• 2007

배리어(dielectric-barrier discharge: DBD) 반응기에서 솔-젤 방법으로 제조한 $Pt/TiO_2$를 넣고 플라즈마 에너지를 사용하여 메탄전환반응 연구를 수행하였다. 제조된 촉매는 기존 금속산화물과는 다른 방법으로 환원을 하였으며, 플라즈마를 사용한 환원방법(plasma-assisted reduction: PAR)이라고 명명하였다. $Pt/TiO_2$ 촉매는 Pt 담지량 및 소성온도에 관계없이 20분 이내에 환원이 완료되었다. 3 wt% $Pt/TiO_2$ 촉매와 5 wt% $Pt/TiO_2$ 촉매를 $600^{\circ}C$에서 소성하여 PAR 방법으로 환원했을 때 메탄의 전환율은 40%로 가장 높았다. DBD 반응기에서 $Pt/TiO_2$ 촉매를 사용하였을 경우 촉매가 없을 때보다 $C_2H_6$, $C_3H_8$와 $C_4H_{10}$과 같은 알칸의 선택성의 매우 높게 나타났다.

• 한국유체기계학회 논문집
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• 제15권3호
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• pp.46-50
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• 2012

Plasma actuator makes parallel flow on the wall surface by the interaction between plasma and neutral air particles. Dielectric barrier discharge (DBD) plasma actuator is widely studied as one type of plasma actuators, which consists of one electrode exposed to the environmental gas and the other encapsulated by a dielectric material. This paper is experimentally focused on the performance of DBD plasma actuator mounted on a flat plate, which depends on kinds of the electrode materials, their thicknesses and the supplied voltage including its frequency. We measured the velocity magnitudes of the induced flow by a stagnation probe as a performance parameter of the plasma actuators. The velocity profiles of the flow induced by the plasma actuators are similar in all measurement cases. The magnitude of the induced velocity is strongly influenced by the thickness of the electrodes and the frequency of the input voltage. The performance of DBD plasma actuators is related to the electric properties of the electrode materials such as the ionization energy and the electrical resistivity.

• 한국대기환경학회지
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• 제20권5호
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• pp.625-632
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• 2004

Perfluorocompounds ($PFC_s$), such as tetrafluoromethane ($CF_4$) and hexafluoroethane ($C_2F_6$), have been widely used as plasma etching and chemical vapor deposition (CVD) gases for semiconductor manufacturing processes. Since these $PFC_s$ are known to cause a greenhouse effect intensively, there has been a growing interest in reducing $PFC_s$ emissions. Among various $CF_4$ decomposing techniques, a dielectric barrier discharge (DBD) is considered as one of a promising candidate because it has been successfully used for generating ozone ($O_3$) and decomposing nitrogen oxide (NO). Firstly, optimal concentration of oxygen for $CF_4$ decomposition was found to figure out how many primary and secondary reactions are associated with DBD process. Secondary, to find effective discharge method for $CF_4$ decomposition, a streamer and a glow mode in DBD are experimentally compared, which includes (i) coaxialcylinder DBD, (ii) DBD reactor packed with glass beads. and (iii) a glow mode operation with a helium gas. The test results showed that optimal concentration of oxygen was ranged 500 ppm~1% for treating 500 ppm of $CF_4$ and helium glow discharge was the most efficient one to decompose $CF_4$.