• Title/Summary/Keyword: Stable discharge

Search Result 415, Processing Time 0.025 seconds

Influence of intermixed gas on stable townsend discharge (안정 Townsend 방전에 대한 혼입가스의 영향)

  • 하성철
    • 전기의세계
    • /
    • v.30 no.5
    • /
    • pp.306-312
    • /
    • 1981
  • The Townsend discharge domain is generally observed with stable positive characteristics in N$_{2}$ gas discharge at low pressures differently in the others, which transfer immediately to glow dischage after self-sustaining discharge starts. In this paper, the presence of the stable Townsend discharge, applied voltage-discharge current characteristics and the effect of disgased electrode surface on stable townsend discharge are studied experimentaly in N$_{2}$ gas mixed with 0.05% of No in volume. As the result of this experiment, the stable Townssend discharge is observed only in pure nitrogen with the valve of pd.geq.8[torr.cm] (p=gas pressure, d=gap spacing), but not in gas mixtures. This is considered that No gas in gas mixtures disexcites effectively the metestble state of nitrogen.

  • PDF

A New Driving Waveform for Stable Address Discharge in an Alternating Current Plasma Display Panel

  • Kim, Sung-Hwan;Seo, Jeong-Hyun;Lee, Seok-Hyun
    • 한국정보디스플레이학회:학술대회논문집
    • /
    • 2004.08a
    • /
    • pp.503-506
    • /
    • 2004
  • In this paper, we suggest a new driving waveform for stable address discharge in AC PDP without the reduction of contrast ratio. To analyze the influence of cross-talk between discharge and non-discharge cells and verify that proposed waveform shows a stable address discharge, we measured the address discharge delay time. The proposed waveform shows the reduction of the cross-talk and concurrently the improvement of address voltage margin compared with those of selective reset waveform having one reset period in 1TV-Field..

  • PDF

Channel-forming discharge calculation and stable channel section evaluation for downstream reach of Yeongju dam in Naesung stream (내성천의 영주댐 하류 구간의 하도형성유량 산정 및 안정하도 단면 평가)

  • Jang, Eun-Kyung;Ahn, Myeonghui;Ji, Un
    • Journal of Korea Water Resources Association
    • /
    • v.51 no.3
    • /
    • pp.183-193
    • /
    • 2018
  • Channel-forming discharge for downstream section of Yeongju dam in Naesung stream was calculated to analyze stable channel geometry. Determined channel-forming discharge was applied to design stable channel slope, depth, and base width at Yonghyeol station. Used data for channel-forming discharge and stable channel analysis were collected in downstream section of Yeongju dam in Naesung stream before the dam construction. Specified recurrence interval discharge, effective discharge, and bankfull discharge were analyzed and compared to decide final channel-forming discharge which was $260m^3/s$ of bankfull discharge. Stable channel analysis and design program was applied to predict stable channel section of width, depth, and slope with various sediment transport equations of Ackers and White, Brownlie, Engelund and Hansen, and Yang's equations. As a result, all equations of sediment transport produced milder slopes compared to current bed slope of 0.00177 and Ackers and White equation presented the most similar flow depth of current section with the design constraint of current channel width.

Flat Fluorescent Lamp for LCD Backlighting (LCD 후면 광원용 평판형광램프)

  • Kwon, Soon-Seok
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
    • /
    • v.21 no.2
    • /
    • pp.15-19
    • /
    • 2007
  • A 15[inch] diagonal mercury-free flat discharge lamp with insulated electrode has been developed as backlight for a LCD backlighting. When the drive voltage pulse conditions were set properly, a uniform and stable discharge extends over the entire volume. It was obtained luminance of $10,330[cd/m^2]$ without prism sheet in uniform and stable discharge.

Effect of Sheath Structure on Operating Stability in an Anode Layer Thruster

  • Yasui, Shinsuke;Yamamoto, Naoji;Komurasaki, Kimiya;Arakawa, Yoshihiro
    • Proceedings of the Korean Society of Propulsion Engineers Conference
    • /
    • 2004.03a
    • /
    • pp.245-250
    • /
    • 2004
  • The discharge current oscillation has been measured for various hollow anode widths and its axial positions using a 1㎾-class anode layer hall thruster. As a result, there were thresholds of magnetic flux density for stable discharge. The plasma structure inside the hollow anode was numerically analyzed using the fully kinetic 2D3V Particle-in-Cell (PIC) and Direct Simulation Monte Carlo (DSMC) methods. The results reproduced both stable and unstable operation modes. In the stable operation case, which corresponds to the case with low magnetic flux, the plasma penetrated into the hollow anode deeper than the case with higher magnetic flux density case. This suggests that comparably large substantial anode area should contribute to stable operation.

  • PDF

Sediment discharge assessment and stable channel analysis using Model Tree of data mining for Naesung Stream (데이터 마이닝의 Model Tree를 활용한 내성천의 유사량 산정 및 안정하도 평가)

  • Jang, Eun-Kyung;Ji, Un;Ahn, Myeonghui
    • Journal of Korea Water Resources Association
    • /
    • v.51 no.11
    • /
    • pp.999-1009
    • /
    • 2018
  • A Model Tree technique of data mining was applied to derive optimal equations for sediment discharge assessment based on the measured sediment data and then to evaluate stable channel design for Naesung Stream. The sediment discharge formula as a function of channel width, velocity, depth, slope and median grain diameter which was developed by a Model Tree technique with sediment discharge data measured in Korean River had a high goodness-of-fit between measured and calculated results. In case of the sediment discharge formula as a function of channel width, velocity, depth and median grain diameter which was developed by a Model Tree technique with sediment discharge data only measured in Naesung Stream represented the highest goodness-of-fit. Two types of sediment discharge formulas were applied to evaluate stable channel analysis for Yonghyeol Station of Naesung Stream. As a result, bed erosion was expected in the study section compared to the current section. It was also presented that the be slope might be changed to be a milder slope than the current slope to reach equilibrium condition in the long term.

A Study on the Temperature-Dependent Discharge Characteristics in Alternating Current Plasma Display Panel (AC PDP의 온도에 따른 방전 특성 연구)

  • Lee, Seok-Hyun;Kim, Jee-Yong
    • The Transactions of The Korean Institute of Electrical Engineers
    • /
    • v.56 no.3
    • /
    • pp.577-582
    • /
    • 2007
  • The plasma display panel is an image expression display using gas discharge plasma. However, gas discharge characteristics vary with temperature as gas discharge is sensitive to temperature. The discharge time lag extends a lot in low temperature and it is known as the cause which hinders high speed addressing which is essential for the size enlargement of the panel. Accordingly this research aims at identifying the temperature-dependent discharge characteristic. The lower temperature becomes, the longer addressing discharge time lag becomes. Particularly the statistical time lag extends much in low temperature. The increasing of electric field shortens discharge time lag in low temperature. Also, when priming particles are sufficiently supplied, stable discharge can be performed regardless of the influence of temperature.

Characteristics of Double Polarity Source-Grounded Gate-Extended Drain NMOS Device for Electro-Static Discharge Protection of High Voltage Operating Microchip (마이크로 칩의 정전기 방지를 위한 DPS-GG-EDNMOS 소자의 특성)

  • Seo, Yong-Jin;Kim, Kil-Ho;Lee, Woo-Sun
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
    • /
    • 2006.06a
    • /
    • pp.97-98
    • /
    • 2006
  • High current behaviors of the grounded gate extended drain N-type metal-oxide-semiconductor field effects transistor (GG_EDNMOS) electro-static discharge (ESD) protection devices are analyzed. Simulation based contour analyses reveal that combination of BJT operation and deep electron channeling induced by high electron injection gives rise to the 2-nd on-state. Thus, the deep electron channel formation needs to be prevented in order to realize stable and robust ESD protection performance. Based on our analyses, general methodology to avoid the double snapback and to realize stable ESD protection is to be discussed.

  • PDF

A Study on the Gap Voltage and Machining Stability in Diesinking Electrical Discharge Machining (형조 방전가공에서 극간 전압과 가공 안정성에 관한 연구)

  • 김광열;이상민;이건기
    • Journal of Advanced Marine Engineering and Technology
    • /
    • v.27 no.3
    • /
    • pp.429-436
    • /
    • 2003
  • The electrical discharge machining(EDM) with Si electrode instead of Gr or Cu electrode. made enormous effects on the surface. machining time, anti-caustic workpiece surface and so on In this paper. we experimented on the inter-role distance during discharge the electrical phenomenon of inter-pole, the distribution of discharge point. the distribution of off load time. etc., using Si electrode Cu electrode and Gr electrode under the same machining condition. As a result of a large quantity generated exclusive powders. the performance of the EDM using Si electrode. compared with EDM using others. is improved. We show that the quantities of those make far pole-gap discharge and discharge scatter under stable machining status possible.

Design and Development of Micro Combustor (II) - Design and Test of Micro Electric Spark discharge Device for Power MEMS - (미세 연소기 개발 (II) - 미세동력 장치용 미세 전극의 제작과 성능평가 -)

  • Gwon, Se-Jin;Lee, Dae-Hun;Park, Dae-Eun;Yun, Jun-Bo;Han, Cheol-Hui
    • Transactions of the Korean Society of Mechanical Engineers B
    • /
    • v.26 no.4
    • /
    • pp.524-530
    • /
    • 2002
  • Micro electric spark discharge device was fabricated on a FOTURAN glass wafer using MEMS processing technique and its performance of electron discharge and subsequent formation of ignition kernel were tested. Micro electric spark device is an essential subsystem of a power MEMS that has been under development in this laboratories. In a combustion chamber of sub millimeter scale depth, spark electrodes are formed by electroplating Ni on a base plate of FOTURAN glass wafer. Optimization of spark voltage and spark gap is crucial for stable ignition and endurance of the electrodes. Namely, wider spark gaps insures stable ignition but requires higher ignition voltage to overcome the spark barrier. Also, electron discharge across larger voltage tends to erode the electrodes limiting the endurance of the overall system. In the present study, the discharge characteristics of the proptotype ignition device was measured in terms of electric quantities such as voltage and currant with spark gap and end shape as parameters. Discharge voltage shows a little decrease in width of less than 50㎛ and increases with electrode gap size. Reliability test shows no severe damage over 10$\^$6/ times of discharge test resulting in satisfactory performance for application to proposed power MEMS devices.