• 한국조명전기설비학회:학술대회논문집
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• 한국조명전기설비학회 2006년도 춘계학술대회 논문집
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• pp.391-394
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• 2006

This paper presents soft switching zero voltage switching high frequency inverter for rare gas fluorescent lamp using dielectric-barrier discharge phenomenon. The simple high-frequency inverter can completely achieve stable zero voltage soft switching (ZVS) commutation for wide its output power regulation ranges and load variations under its constant high frequency pulse density modulation (PDM) scheme. Its transient and steady state operating principle is originally described and discussed for a constant high-frequency PDM control strategy under a stable ZVS operation commutation, together with its output effective power regulation characteristics-based on the high frequency PDM strategy. The experimental operating performances of this high frequency Inverter are illustrated as compared with computer simulation results and experimental ones. Its light dimming characteristics due to power regulation scheme are evaluated and discussed on the basis of simulation and experimental results. The feasible effectiveness of this high frequency inverter appliance implemented here is proven from the practical point of view.

• 한국환경과학회지
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• 제28권5호
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• pp.495-502
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• 2019

This study was conducted to investigated the possibility of inactivating wilt germs (Fusarium oxysporum f. sp. radicis lycopersici) using Dielectric Barrier Discharge (DBD) plasma in a hydroponic system. Recirculating hydroponic cultivation system for inactivation was consisted of planting port, LED lamp, water tank, and circulating pump for hydroponic and DBD plasma reactor. Two experiments were conducted: batch and intermittent continuous process. The effect of plasma treatment on Total Residual Oxidants (TRO) concentration change, Fusarium inactivation and growth of lettuce were investigated. In the batch experiment, most of the Fusarium was inactivated at a TRO concentration of 0.15 mg/L or more at four-day intervals. There was no change in lettuce growth after two times of plasma treatment for one week. The intermittent continuous experiment consisted of 30-minute, 60-minute, and 90-minute plasma treatment in 2 day intervals and 30-minute treatment a one-day; most of the Fusarium was inactivated only by treatment for 30-minute every two days. However, if inactivation under $10^1CFU/mL$ is required, it will be necessary to treat for 60 minutes in 2 day intervals. The plasma treatment caused no damage to the lettuce, except the 30 min plasma treatment ay the one-day interval. It was considered that the residual TRO concentration was higher than that of the other treatments.

• 한국재료학회지
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• 제33권4호
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• pp.115-123
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• 2023

In this paper, we report and discuss the semi-permanently hydrophilic (SPH) treatment of polyester fabric using plasma polymerization and oxidation based on atmospheric pressure dielectric barrier discharge (APDBD) technology. SiO_xC_y(-H) was coated on polyester fabric using Hexamethylcyclotrisiloxane (HMCTSO) as a precursor, and then plasma oxidation was performed to change the upper layer of the thin film to SiO₂-like. The degradation of hydrophilicity of the SPH polyester fabrics was evaluated by water contact angle (WCA) and wicking time after repeated washing. The surface morphology of the coated yarns was observed with scanning electron microscopy, and the presence of the coating layer was confirmed by measuring the Si peak using energy dispersive x-ray spectroscopy. The WCA of the SPH polyester fabric increased to 50 degrees after 30 washes, but it was still hydrophilic compared to the untreated fabric. The decrease in hydrophilicity of the SPH fabric was due to peeling of the SiO_xC_y(-H) thin film coated on polyester yarns.

• 공업화학
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• 제23권6호
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• pp.608-613
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• 2012

유전체 배리어 방전 플라즈마를 모사 농산물 저장시설($1.0m^3$)의 에틸렌 제거에 적용하였다. 에틸렌이 포함된 공기를 플라즈마 반응기에 유입시켜 처리한 후 다시 농산물 저장시설로 재순환하는 방식으로 시험을 수행하였다. 주요 운전변수는 방전전력, 순환기체 유량, 초기 에틸렌 농도 및 처리시간이었다. 에틸렌의 분해속도는 주로 방전전력과 처리시간에 의해 결정되었다. 다른 조건을 일정하게 유지한 상태에서 플라즈마 반응기 후단에 이산화망간 오존분해 촉매를 설치했을 경우 오존분해 촉매가 없을 때 보다 에틸렌 제거속도가 더 빨랐는데, 이 결과는 플라즈마 반응기에서 배출되는 오존이 농산물 저장시설에 유입 축적되어 에틸렌을 추가적으로 분해했기 때문이다. 에틸렌 초기 농도 50 ppm을 기준으로 하면 이를 완전히 분해하기 위한 에너지 요구량은 약 60 kJ이었다.

• 한국산업융합학회 논문집
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• 제26권1호
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• pp.163-173
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• 2023

In this study, topographic change analysis was performed on the Nak-dong River estuary area. The factors affecting the changes in the bathymetry of the Nak-dong River estuary were analyzed using data from the discharge, suspended sediments, and rainfall of the Nak-dong River barrier as analysis data. As a result, erosion and sedimentation are judged to appear repeatedly due to complex effects such as discharge of the estuary barrier of the Nak-dong River and invasion of the open sea waves, and it is judged that there is no one-sided tendency. However, as a result of checking the data in the second half of 2020, it was possible to confirm a large amount of erosion, which is different from the past data. It is clear that this is a result beyond the trend of erosion in the first half and sedimentation in the second half. In the summer of 2020, the rainy season lasted for more than a month and torrential rains occurred, which seems to be due to about three times higher rainfall than other periods, and erosion is believed to have occurred as the discharge increased rapidly compared to the time deposited by river water outflow. In addition, compared to other times, the influence of many typhoons in the summer of 2020 is believed to have affected the topographical change at the mouth of the Nak-dong River.

• Journal of Korean Society for Atmospheric Environment
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• 제18권E1호
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• pp.13-20
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• 2002

The electrical and chemical properties of the dielectric barrier discharge (DBD) process for the benzene removal were investigated. The benzene removal was initiated with the applied voltage higher than the discharge onset value. The removal efficiency over 95 % was obtained at approximately 1.6 kJ lite $r^{r-1}$ of the electrical energy density. The increase of the inlet concentration decreased the removal efficiency. However, the benzene decomposition rate increased with the inlet concentration . While the increase of the gas retention time enhanced the removal efficiency, the decomposition rate decreased. Identification of the optimum condition between the decomposition rate and the removal efficiency is required for field applications of the DBD process.s.

• 한국대기환경학회:학술대회논문집
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• 한국대기환경학회 2000년도 추계학술대회 논문집
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• pp.407-408
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• 2000

유전체 장벽 방전 반응기 (Dielectric Barrier Discharge (DBD) Reactor)를 이용한 비열 플라즈마(Non-thermal plasma) 공정에서 NO 제거 특성을 실험적으로 연구하였다. 질소 분위기에서 전자에 의한 NO 의 제거는 $N_2$ + e $\longrightarrow$ N + N + e 반응에 의한 질소의 전자충돌해리 (electron-impact dissociation)와 이 반응에 의하여 생성된 질소원자에 의한 NO 의 환원반응 N + NO $\longrightarrow$ $N_2$ + O 으로 설명될 수 있으며, 이로 인하여 $O_2$ 나 $H_2O$ 의 첨가에 따른 부산물(O, $O_3$, OH 등)에 의한 산화반응이 주로 일어나는 경우 (XO + NO $\longrightarrow$ X + NO$_2$) 와는 달리 NO 제거에 소모된 에너지를 평가하기에 용이한 장점이 있다(Penetrante et al., 1995). (중략)

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2002년도 International Meeting on Information Display
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• pp.75-78
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• 2002

Difference in the structure of AC PDP cells makes the cells have various discharge characteristics. Therefore, a ramp-reset must be adjusted for the stable driving of AC PDP. If any ramp-reset can reduce the difference in discharge characteristics between cells, the conditions of the address discharge could become almost the same. It is very important to understand these to design a good driving waveform. In this paper, we proved the mentioned facts with the change of barrier rib heights.

• 한국표면공학회:학술대회논문집
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• 한국표면공학회 2009년도 춘계학술대회 논문집
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• pp.95-95
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• 2009

대기압 플라즈마 발생장치를 이용한 식각장비 개발은 낮은 공정단가, 저온 공정, 다양한 표면처리 응용 효과와 같은 이점을 가지고 있어 현재, 많은 분야에서 연구되고 있다. 본 연구에서는, dielectric barrier discharge(DBD) 방식을 이용한 대기압 발생장치를 통해 평판형 디스플레이 제작에 응용이 가능한 $SiO_2$ 층의 식각에 대한 연구를 하였다. $N_2/NF_3$ gas 조합에 $CF_4$ 또는 $C_{4}F_{8}$ gas를 부가적으로 첨가하였다. 이때 N2 60 slm / NF3 600 sccm/CF4 7 slm/Ar 200 sccm의 gas composition에서 최대 260 nm/min의 식각 속도를 얻을 수 있었다.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2009년도 9th International Meeting on Information Display
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• pp.1500-1503
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• 2009

In this paper, we studied about atmospheric pressure remote plasma ashing of photoresist(PR), by using a modified dielectric barrier discharge(DBD). The effect of various gas combinations such as $N_2/O_2$, $N_2/O_2+SF_6$ on the changes PR ashing rate was investigated as a function of power. The maximum PR ashing rate of 1850 nm/min was achieved at $N_2$ (70 slm)/ $O_2$ (200 sccm) + $SF_6$ (3 slm). We found that as the oxygen and fluorine radical peaks were increased, the ashing rate is increased, too.