• 제목/요약/키워드: Cathode Power

검색결과 544건 처리시간 0.026초

비친수성유기물질(HOC)로 오염된 토양의 정화를 위한 동전기-생물활성화공정의 개발

  • 양지원;김상준;박지연;이유진;기대정
    • 한국지하수토양환경학회:학술대회논문집
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    • 한국지하수토양환경학회 2003년도 추계학술발표회
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    • pp.326-329
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    • 2003
  • When an electrokinetic process is applied to a HOC-contaminated soil, hybrid types combined with soil flushing, chemical oxidation, and bioremediation are generally used. Especially when the electrokinetic process is combined with bioremediation, the hybrid technology can solve several limits of bioremediation such as low microbial mobility, low soil temperature, and shortage of nutrients in subsurface circumstance. Because microbial surface is charged negatively, the microorganism moves from cathode to anode under electrical field. In this study, mixed culture mainly-consisted by Pseudomonas sp. was applied to remediate pentadecane-contaminated kaolinite with particle size less than 300${\mu}{\textrm}{m}$. This remediation system was named ‘electrokinetic bioaugmentation’ and consisted of model aquifer, electrode reservoirs, bioreactor, power supply, and pump. The mixed culture above 0.5 of optical density in bioreactor was supplied to two reservoirs and penetrated soil when the electric current was applied. To enhance the removal efficiency, the optimal medium composition, electric current, and voltage were investigated.

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Lithium Air Battery: Alternate Energy Resource for the Future

  • Zahoor, Awan;Christy, Maria;Hwang, Yun-Ju;Nahm, Kee-Suk
    • Journal of Electrochemical Science and Technology
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    • 제3권1호
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    • pp.14-23
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    • 2012
  • Increasing demand of energy, the depletion of fossil fuel reserves, energy security and the climate change have forced us to look upon alternate energy resources. For today's electric vehicles that run on lithium-ion batteries, one of the biggest downsides is the limited range between recharging. Over the past several years, researchers have been working on lithium-air battery. These batteries could significantly increase the range of electric vehicles due to their high energy density, which could theoretically be equal to the energy density of gasoline. Li-air batteries are potentially viable ultra-high energy density chemical power sources, which could potentially offer specific energies up to 3000 $Whkg^{-1}$ being rechargeable. This paper provides a review on Lithium air battery as alternate energy resource for the future.

아르곤 이온빔을 이용한 CNT 페이스트 에미터의 표면처리에 관한 연구 (A Study on the Surface Treatment of CNT Paste Emitter by Ar Ion Irradiation)

  • 권상직
    • 한국전기전자재료학회논문지
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    • 제20권5호
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    • pp.456-461
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    • 2007
  • In this study, a surface treatment method using accelerated Ar ions was experimented for exposing the carbon nanotubes (CNT) from the screen-printed CNT paste. After making a cathode electrode on the glass substrate, photo sensitive CNT paste was screen-printed, and then back-side was exposed by UV light. Then, the exposed CNT paste was selectively remained by development. After post-baking, the remained CNT paste was bombarded by accelerated Ar ions for removing some binders and exposing only CNTs. As results, the field emission characteristics were strongly depended on the accelerating energy, bombardment time, and the power of RF plasma ion source. When Ar ions accelerated with 100 eV energy from the 100 W RF plasma source are bombarded on the CNT paste surface for 10 min, the emission level and the uniformity were best.

Changes of Electrical Conductivity and Temperature Caused by Cathode Erosion in a Free-Burning Argon Arc

  • 전홍필;이종철
    • 한국진공학회:학술대회논문집
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    • 한국진공학회 2014년도 제46회 동계 정기학술대회 초록집
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    • pp.255.2-255.2
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    • 2014
  • Electrode erosion is indispensable for atmospheric plasma systems, as well as for switching devices, due to the high heat flux transferred from arc plasmas to contacts, but experimental and theoretical works have not identified the characteristic phenomena because of the complex physical processes. Our investigation is concerned with argon free-burning arcs with anode erosion at atmospheric pressure by computational fluid dynamics (CFD) analysis. We are also interested in the energy flux and temperature transferring to the anode with a simplified unified model of arcs and their electrodes. In order to determine two thermodynamic quantities such as temperature and pressure and flow characteristics we have modified Navier-Stokes equations to take into account radiation transport, electrical power input and the electromagnetic driving forces with the relevant Maxwell equations. From the simplified self-consistent solution the energy flux to the anode can be derived.

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외부전극 형광램프의 저온구동을 위한 새로운 벅부스트 하프브리지 인버터 (A New Buck-Boost Half Bridge Inverter for Low Temperature Driving of EEFL)

  • 조규민;오원식;문건우;박문수;이상길
    • 전력전자학회:학술대회논문집
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    • 전력전자학회 2006년도 전력전자학술대회 논문집
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    • pp.387-389
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    • 2006
  • The LCD TV has many variable functions for consumer. Low temperature driving below minus 20 degree is also one of key functions. Since LCD is not self-luminance device, it is needed backlight system. Recently EEFL(External Electrode Fluorescent Lamp) widely substitutes for CCFL(Cold Cathode Fluorescent Lamp). It is more cheaper, higher efficiency, and easy to drive parallel connection compared to CCFL. In this paper, several conditions for low temperature driving of EEFL are investigated and a new boost-half bridge inverter for low temperature driving is proposed. Mode analysis is described and experimental results is represented to verify validity of the proposed inverter.

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EEFL 인버터의 Dimming 제어 특성 (Dimming Control Characteristics of External Electrode Fluorescent Lamp Inverter)

  • 서은경;임정규;정세교;이대식;방배규
    • 전력전자학회:학술대회논문집
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    • 전력전자학회 2006년도 전력전자학술대회 논문집
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    • pp.393-395
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    • 2006
  • This Paper represents a dimming control characteristics of an external electrode fluorescent lamp (EEFL) inverter, which is replacing a cold cathode (luorescent lamp (CCFL) in the area of the large-sized LCD backlight. The analog and burst dimming control methods for the EEFL are compared and the control characteristics are anlayzed through the experiments.

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LCD 백라이트용 트랜스포머 없는 냉음극관(CCFL) 구동 회로 (Transformer-less CCFL Driver for LCD Backlight)

  • 최은석;윤현기;문건우;윤명중;강문식
    • 전력전자학회:학술대회논문집
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    • 전력전자학회 2006년도 전력전자학술대회 논문집
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    • pp.81-83
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    • 2006
  • The conventional cold cathode fluorescent lamp (CCFL) driver for LCD TV has a transformer for each lamp to step up the high sinusoidal waveform from the low input voltage. The transformer used in the conventional topology causes the driver to have bulky size and high cost. This paper proposes a new transformer-less CCFL driver for LCD backlight that is based on the parallel-loaded resonant inverter topology. This resonant topology enables the circuit to supply enough high voltage for CCFL without a transformer. Also, with current-balancing technique, this transformer-less inverter drives 16 CCFL lamps.

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압전 변압기 구동을 위한 인버터 회로설계 (Design of the inverter circuits for driving a piezoelectric transformer)

  • 권기현;임영철;조성구;양승학;윤석진
    • 전력전자학회:학술대회논문집
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    • 전력전자학회 2003년도 춘계전력전자학술대회 논문집(2)
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    • pp.616-620
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    • 2003
  • 액정 디스플레이의 백라이트에 사용되는 냉음극 방전램프(CCFL: Cold Cathode Fluorescent Lamp) 구동 인버터의 설계함에 있어 압전 변압기(Piezoelectric Transformer)를 사용하였으며, 파라미터 선정 및 최적화를 하여 실험을 통해 검증하였다. 적용한 압전 인버터로는 푸시-풀(Push-pull)과 하프-브리지(Half-bridge) 회로이며, 휘도 제어기법으로는 아날로그(Analog)와 버스트(Burst) 방법을 사용하였다. 푸시-풀 인버터의 경우 아날로그 제어방식으로 제어전압 2.5-4.5V에서 출력전류 1-6mA(최소)로 휘도 0-100$\%$ 특성을 보였다. 입출력 효율로 18.6(최소)-90.3(최대)$\%$를 얻었으며, 버스트 제어방식에서는 듀티비 50-5$\%$에서 1-6mA의 제어 성능을 보였다. 인버터의 입출력 효율은 13.6(최소)-82.1(최대)$\%$를 얻었다.

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압전 변압기를 기반으로 한 LCD 구동 인버터 설계 (Design of the piezoelectric transformer based LCD drive system)

  • 조성구;권기현;임영철;양승학
    • 전력전자학회:학술대회논문집
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    • 전력전자학회 2003년도 추계학술대회 논문집
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    • pp.197-201
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    • 2003
  • 액정 디스플레이의 백라이트에 사용되는 냉음극 방전램프(CCFL: Cold Cathode Fluorescent Lamp) 구동 인버터의 설계함에 있어 압전 변압기(Piezoelectric Transformer)를 사용하였으며, 파라미터 선정 및 최적화를 하여 실험을 통해 검증하였다. 적용한 압전 인버터로는 푸시-풀(Push-pull)과 하프-브리지(Half-bridge) 회로이며, 휘도 제어기법으로는 아날로그(Analog)와 버스트(Burst) 방법을 사용하였다. 푸시-풀 인버터의 경우 아날로그 제어방식으로 제어전압 2.5-4.5V에서 출력전류 1-6mA(최소)로 휘도 $0-100\%$ 특성을 보였다. 입출력 효율로 18.6(최소)-90.3(최대)$\%$를 얻었으며, 버스트 제어방식에서는 듀티비 $5-50\%$에서 1-6mA의 제어성능을 보였다. 인버터의 입출력 효율은 13.6(최소)-82.1(최대)$\%$를 얻었다.

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Development of High Performance Backlight Unit Employing EEFL

  • Yoo, Hyeong-Suk;Kang, Moon-Shik;Lim, Jong-Sun;Lee, Keun-Woo;Oh, Weon-Sik;Park, Jong-Dae;Kang, Sung-Chul
    • 한국정보디스플레이학회:학술대회논문집
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    • 한국정보디스플레이학회 2002년도 International Meeting on Information Display
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    • pp.835-837
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    • 2002
  • The 17" Backlight Unit (BLU) employing twelve EEFLs (External Electrode Fluorescent Lamp) has been developed for LCD-TV The characteristics of the EEFL BLU without dual brightness enhancement film (DBEF) were equivalent to those of CCFL (Cold cathode Fluorescent Lamp) BLU employing eight CCFLs with DBEF. Luminance, power consumption and uniformity were 12,000nits, 32watt and 80%, respectively. The inverter of EEFL Backlight Unit is composed of 2 transformers and driven by the sinusoidal waveform.

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