• Title/Summary/Keyword: DBD

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Development of a Flow Sensor Using DBD (Dielectric Barrier Discharge) (DBD (Dielectric Barrier Discharge)를 이용한 유량 센서 개발에 관한 연구)

  • Kim, Tae-Hoon;Kim, Sung-Jin
    • Proceedings of the KSME Conference
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    • 2008.11b
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    • pp.2076-2081
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    • 2008
  • In this study, a new concept of a flow sensor is developed using dielectric barrier discharge (DBD). Current of DBD generated between two electrodes is changed with varying flow rates. Therefore, it is possible to measure the flow rate by correlating generated DBD current with flow rates. The effects of flow rate, frequency, channel height, diameter of electrodes and distance between electrodes on the performance of the flow sensor using DBD are experimentally investigated.

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Ar DBD 플라즈마의 ROS가 히드라 출아에 미치는 영향

  • Jeong, Gwan-Ho;Hwang, Chang-Ha;Byeon, Ji-Hyeon;Im, Jun-Seop;Nam, Cheol-Ju;Choe, Eun-Ha
    • Proceedings of the Korean Vacuum Society Conference
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    • 2016.02a
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    • pp.208.1-208.1
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    • 2016
  • 히드라란 단세포 생물로써 강장동물에 속한다. 촉수가 많이 있으며, 그 촉수에는 독이 있다. 번식 방식으로는 출아법을 이용한다. 출아를 할 때에는 한 마리가 아닌 여러 마리의 히드라가 동시에 출아를 하기도 하며, 출아를 하고 있는 히드라는 촉수가 들어난 순간부터 먹이 섭취가 가능해진다. 이 출아법을 이용하여 번식을 하는 히드라가 DBD처리를 했을 시, 히드라 출아에 차이를 보인다면 다른 생물에게도 DBD 처리를 했을 시, 영향을 미친다고 생각하고 실험을 진행하였다. DBD(Dielectric Barrier Discharge)는 두 전극 사이에 유전체층이 있으며, 외부에서 교류 전압을 가해준다. 그러면 유전체 사이에서 방전이 발생되는데, 방전된 것을 플라즈마라고 한다. DBD라는 유전체 장벽 방전으로써 주위를 이온화 시켜 만드는 플라즈마에 유전체를 씌어 생물에게 최대한 해가 되지 않도록 만든 것이다. 유전체 장벽 방전에ROS(Reactive Oxygen Species)라는 산소와 결합된 기체들이 생성된다. DBD로 인해서 생성되는 ROS를 히드라에 처리했을 경우 히드라 출아수에 변화를 통해서 해를 끼치는 정도를 알아보고자 하였다. 그 결과 아르곤 기체에 의한 ROS로 처리한 히드라는 대조군 보다 히드라의 출아수의 변화가 있는 것으로 관찰되었고, 공기를 이용하여 방전한 DBD의 ROS로 처리한 히드라는 대조 군과 비교하여 큰 변화가 없어 보였다. 따라서 아르곤 대기압 DBD플라즈마를 이용하여 만든 ROS가 히드라에게 직접적인 영향을 준 것으로 보였다. 이 결과를 토대로 아르곤DBD를 이용한 ROS 처리는 생물에게 영향을 줄 수 있다는 것을 이 실험을 통해 간접적으로 확인해 볼 수 있었다.

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Study on Characteristics of DBD Plasma Actuator as Design Parameters for Plasma Flow Control (플라즈마 유동제어를 위한 DBD 플라즈마 액츄에이터의 설계변수에 따른 특성 연구)

  • Yun, Su-Hwan;Kwon, Hyeok-Bin;Kim, Tae-Gyu
    • Journal of the Korean Society for Aeronautical & Space Sciences
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    • v.40 no.6
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    • pp.492-498
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    • 2012
  • Characteristics of DBD(Dielectric Barrier Discharge) plasma actuator as design parameters were investigated for plasma flow control. Flow velocity and power consumption of the DBD plasma actuator were measured according to the design parameters such as discharge voltage and frequency, gap, width and length of electrode, and the thickness of dielectric barrier. The flow velocity and power consumption increased as the discharge voltage and frequency increased. As the electrode gap increased, the flow velocity increased with decreasing the power consumption, whereas high voltage was required for the plasma discharge. The flow velocity increased as the upper-electrode width decreased, and as the lower-electrode width increased at the constant power consumption. The performance of the DBD plasma actuator can be estimated at the given discharge and geometry conditions.

Dioscorea batatas Decne Glycoprotein Prevents Ecotoxicological Effects of Bisphenol A in Gastrointestinal Epithelial Cells and Improves Fecal Malodor and Feed Efficiency in Mice (환경호르몬 비스페놀 A가 유도한 위장관 세포독성 제어효과를 가진 마 당단백질이 마우스의 식이 효율 및 악취저감에 미치는 영향)

  • Kim, Do-Wan;Park, Moon-Ki;Kim, Tae Hoon;Lee, Sei-Jung
    • Journal of Environmental Science International
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    • v.31 no.1
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    • pp.23-31
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    • 2022
  • As a herbal supplement, Dioscorea batatas Decne (DBD) presents potent antioxidant activity and diverse health benefits. In the present study, functions of a 30 kDa glycoprotein isolated from DBD (hereafter, DBD glycoprotein) in the regulation of feed efficiency and fecal malodor in mice were explored. DBD glycoprotein produced protective effect against cytotoxicity induced by the ecotoxicological endocrine-disrupting substance bisphenol A in gastrointestinal epithelial HT-29 cells. To investigate its potential roles in the regulation of feed efficiency and fecal malodor, mice were administered an oral injection of DBD glycoprotein for 2 weeks. Compared with the control values, the weight of internal organs (liver, heart, kidney, and spleen) and levels of glutamate pyruvate transaminase, glutamate oxaloacetate transaminase, and lactic dehydrogenase were not significantly changed during DBD glycoprotein administration for 2 weeks. Interestingly, DBD glycoprotein improved feed efficiency and reduced hydrogen sulfide concentration without altering the ammonia level in mouse feces. Collectively, these results indicate that DBD glycoprotein is a functional agent that exerts gastrointestinal protective effects against ecotoxicological substances, improves feed efficiency, and reduces fecal malodor.

Monostatic RCS Measurement for Dielectric Barrier Discharge Plasma (유전체 장벽 방전 플라즈마의 Monostatic 레이다 단면적 측정)

  • Lee, Hyunjae;Jung, Inkyun;Ha, Jungje;Shin, Woongjae;Yang, Jin Mo;Lee, Yongshik;Yook, Jong-Gwan
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.27 no.3
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    • pp.246-252
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    • 2016
  • In this paper, reduction of monostatic RCS by DBD plasma is measured. For the calibration of monostatic RCS, S-parameters of two metallic plate in different sizes are used and the result is within 0.4 dB error. Metallic plate is put behind DBD plasma generator for measuring reduction of monostatic RCS by DBD plasma. To prevent arc discharge between metallic plate and DBD plasma generator, measurement is progressed spacing the interval between metallic plate and DBD plasma generator. As a result, maximum reduction of monostatic RCS is about 3 dB at 7.4 GHz.

Dynamic Analysis of ATM Double Bill Detector (ATM기 2매 검지부의 동적 해석)

  • Jeong, Joong-Ki;Suh, Jun-Ho;Baek, Yoon-Kil;Choi, Yeon-Sun
    • Transactions of the Korean Society for Noise and Vibration Engineering
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    • v.16 no.12 s.117
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    • pp.1208-1214
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    • 2006
  • ATM(automated-teller machine) is a machine that receives and pays money directly. The double bill detector(DBD) module of an ATM detects double bills from its thickness. In this paper, the dynamic behavior of the DBD was analyzed, which cannot be simulated correctly by a package program of SAMCEF. And the displacements of the lever was measured for various bills experimentally. The measured dynamic behaviors were analyzed kinematically using a vector equation and simulated dynamically by the derivation of equation of motion with consideration of damping and stiffness of the DBD and bills. The analysis showed that the spring constant of the system is not so influential, instead, the contact angle between the lever and bill needs to be larger than the existing DBD in order to be laster and reliable DBD.

Low Voltage Atmospheric Plasma Generation using DBD Initiation Carrier Injection (유전체 장벽 방전(DBD) 씨드 캐리어를 이용한 저 전압 대기압 플라즈마 발생)

  • Hwang, Sol;Park, Hyunho;Kim, Youngmin
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.67 no.1
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    • pp.82-86
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    • 2018
  • Low voltage atmospheric plasma generation using DBD Initiation carrier injection is reported. DBD afterglow was used as initiation carriers prior to a primary discharge and a significant reduction in the breakdown voltage of atmospheric discharge was observed when sufficient initiation carriers were provided. Quantative correlation study between the breakdown voltage and the initiation carriers suggests that the atmospheric breakdown voltage reduces to only half of the breakdown voltage for Townsend regime. Also, use of DBD initiation carrier injection likely offers better device reliability by protecting electrodes with a dielectric layer and thus suppressing electrode wear.

DBD를 이용한 Plasma Jet의 구동 전극 위치에 따른 방전 특성 분석

  • Lee, Yeong-Ho;Ha, Chang-Seung;Lee, Ho-Jun;Kim, Dong-Hyeon;Lee, Hae-Jun
    • Proceedings of the Korean Vacuum Society Conference
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    • 2011.02a
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    • pp.226-226
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    • 2011
  • 소형 대기압 플라즈마 소스는 그 형태에 따라 DBD (Dielectric Barrier Discharge)나 Plasma Needle, 혹은 Plasma Jet 등으로 구별되며, 구동 파형의 특성에 따라 DC, RF (Radio Frequency), 혹은 Pulsed 방식 등으로 나뉜다. 또한 코로나 방전도 소형 대기압 플라즈마 장치에서 사용된다. DBD는 1857년 Siemens에 의해 최초로 보고 되었고 산업 분야에서 대규모로 사용되어 왔다. 본 연구에서는 대향 방전 DBD 대신 유전체 양쪽 면에 전극이 도포된 면방전 형태의 DBD 구조 내부로 He 가스가 흐를 때의 방전에 대한 광학적 진단을 수행하였다. 전극간의 거리와 가스 유속의 변화에 따라 방전 특성이 어떻게 달라지에 대해서 Optical Emission Spectroscopy (OES)를 통하여 생성되는 radical 종의 변화를 측정하고 ICCD (intensified charge coupled device) image를 통해 방전이 시간에 따라 어떻게 진행되는지를 진단하였다.

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Analysis and Performance Evaluation of DBD Actuator for Plasma Flow Control (플라즈마 유동 제어를 위한 DBD 엑츄에이터 해석 및 성능평가)

  • Lee, Chang-Wook;Yun, Su-Hwan;Kim, Tae-Gyu
    • Proceedings of the Korean Society of Propulsion Engineers Conference
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    • 2012.05a
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    • pp.290-293
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    • 2012
  • The analysis and performance evaluation of DBD actuator for plasma flow control was described. The experimental apparatus was designed to measure the flow velocity as the discharge conditions, and to find out the optimal discharge condition of the DBD actuator. The average-velocity increased with increasing the discharge voltage. The experimental results was compared with CFD analysis.

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Stability enhancement of armorphous znic oxide thin film transistors fabricated by pulsed laser deposition with DBD (PLD-DBD 공정으로 제작된 비정질 Zn 산화물 박막트랜지스터의 안정성 향상)

  • Chun, Yoon-Soo;Chong, Eu-Gene;Jo, Kyoung-Chol;Kim, Seung-Han;Jung, Da-Woon;Lee, Sang-Yeol
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2010.06a
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    • pp.391-391
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    • 2010
  • The stability enhancement of Znic oxide thin film transistor deposited by PLD-DBD has been reported here using the bias temperature stress test. Znic oxide (ZnO) thin films were deposited on $SiO_2$/Si (100) by pulsed laser deposition method with and without dielectric barrier discharge (DBD) method. The DBD is the efficient method to adopt the nitrogen ions into the thin films. The TFT characteristics of ZnO TFTs with and without Nirogen (N) doping show similar results with $I_{on/off}$ of $10^5{\sim}10^6$. However. the bias temperature stress (BTS) test of N-doped ZnO TFT with DBD shows higher stability than that of ZnO TFT.

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