• Title/Summary/Keyword: Electric current

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침수 누전에 대한 자계 특성

  • Kim, Tak-Yong;Lee, Gyeong-Seop;Kim, Jin-Sa;Kim, Chung-Hyeok
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2009.11a
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    • pp.147-147
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    • 2009
  • Every year respect a countermeasure establishment the electric leakage detection system and electric leakage investigation work are becoming enforcement line plentifully in about the electric leakage accident which is increasing, measuring in compliance with a most ground connection voltage and an image electric current mainly is become accomplished, inputs a pulsation group signal in the line and detects a signal change between the line a method which there is. In order to investigate the quality in compliance with an electric leakage electric current from the electric leakage area after conferring the electric leakage environment in compliance with a flooding when the electric leakage electric current exists in the surface, it investigated the electric leakage electric current quality from the electric current distribution and flooded districts from the present paper.

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A study on electric current variation characteristics during Electrokinetic remediation of kaolinite contaminated by Pb (납으로 오염된 카올린의 Electrokinetic 정화기법 적용시 전류변화 특성에 관한 연구)

  • 김정환;한상재;김수삼
    • Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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    • 2000.11a
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    • pp.302-306
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    • 2000
  • In case of applying electrokinetic remediation, magnitude of electric current is one of major factors for estimation of contaminant transport. In practice, electric current provide determination of electric conductivity based on specimen resistance. Electric current variation is produced during Electrokinetic remediation test. Electric current is decreased by expotential function according to time in condition of constant voltage. This can be interpreted as precipitation effect by OH$^{-10}$ generation in a cathode.

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단선 누전에 의한 표면자계 특성

  • O, Yong-Cheol;Choe, Mi-Hui;Jeong, Han-Seok;Kim, Jin-Sa;Jo, Chun-Nam;Kim, Chung-Hyeok
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2009.11a
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    • pp.148-148
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    • 2009
  • In order to investigate the quality in compliance with an electric leakage electric current from the electric leakage area after conferring the electric leakage environment in compliance with a flooding when the electric leakage electric current exists in the surface, it investigated the electric leakage electric current quality from the electric current distribution and flooded districts from the present paper. At the result, we have known that flux density is constant regardless of distance variation.

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Anatomy of a flare-producing current layer dynamically formed in a coronal magnetic structure

  • Magara, Tetsuya
    • The Bulletin of The Korean Astronomical Society
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    • v.41 no.2
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    • pp.41.3-42
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    • 2016
  • No matter how intense magnetic flux it contains, a coronal magnetic structure has little free magnetic energy when a composing magnetic field is close to a potential field, or current-free field where no volume electric current flows. What kind of electric current system is developed is therefore a key to evaluating the activity of a coronal magnetic structure. Since the corona is a highly conductive medium, a coronal electric current tends to survive without being dissipated, so the free magnetic energy provided by a coronal electric current is normally hard to release in the corona. This work aims at clarifying how a coronal electric current system is structurally developed into a system responsible for producing a flare. Toward this end, we perform diffusive MHD simulations for the emergence of a magnetic flux tube with different twist applied to it, and go through the process of structuring a coronal electric current in a twisted flux tube emerging to form a coronal magnetic structure. Interestingly, when a strongly twisted flux tube emerges, there spontaneously forms a structure inside the flux tube, where a coronal electric current changes flow pattern from field-aligned dominant to cross-field dominant. We demonstrate that this structure plays a key role in releasing free magnetic energy via rapid dissipation of a coronal electric current, thereby producing a flare.

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A Study on the Detection of Indication of Accident in Electric Equipments with Incandescent Lamps Using Current Monitor (전류 모니터를 이용한 백열등 부하 전기설비에서 사고 징후 검출에 관한 연구)

  • Jee, Seung-Wook;Ok, Kyung-Gea;Kim, Shi-Kuk;Lee, Chun-Ha;Lee, Kwang-Sik
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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    • v.23 no.1
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    • pp.109-115
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    • 2009
  • This paper describes an early detection for indication of electric accident using current waveform which is measured in electric equipments consisted incandescent lamps. At first, it analyzes characteristics of current monitor in resistive electric circuit. In second, the electric equipment is consisted of incandescent lamps. And the electric accident is simulation of tracking according to KS C IEC(Korea Standard C International Electrostatic Commission) 60112 at some part of the electric equipment. The indication of the electrical accident is detected to analyzing current waveform measured by current monitor. As the tracking breakdown, electric accident, processes, as current pulse is bigger and ratio of appearance also is increased irrespective of amount of load.

A study on conduction current and D.C. breakdown characteristics in dielectric liquids (절연유의 도전전류와 직류절연파괴특성에 관한 연구)

  • 서국철
    • 전기의세계
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    • v.30 no.4
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    • pp.231-236
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    • 1981
  • It has been known that D.C. breakdown Voltage is lower than A.C. breakdown Voltage in insulatingoil, but there are still many unvivid points at electric conduction in breakdown or under of high electric field. This study measured the electric current-electric field characteristics (I-E characteristics) and the breakdown Voltage under of D.C. electric field of insulating oil using the system of electrodes that are near the Uniform electric field with a result. I can study, electric conduction in area of high electric field depends upon the Schottky effect. The liquidity of breakdown electric field takes place by the local concentration of electric field. The longer gap is and the more electric current is the more breakdown Voltage decreased. There are not almost the change of electric current-electric field characteristics by materials of electrode.

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Application of a Pulse Electric Field to Cross-flow Ultrafiltration of Protein Solution

  • Kim, Hyong-Ryul;Lee, Kisay
    • Biotechnology and Bioprocess Engineering:BBE
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    • v.4 no.1
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    • pp.46-50
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    • 1999
  • The application of pulsed electric field was investigated in the crossflow ultrafiltration of BSA (bovine serum albumn) to economize the application time of electric current as well as to avoid inherent problems of long-term application of electric field. During the application of various cyclic patterns of pulsed electric current, the averaged filtration flowrate and the degree of concentration were maintained higher than those obtained in the absence of electric current application. The temperature increase, pH change, and BSA loss by electrodeposition were all negligible during the operation. The averaged filtration flowrate increased as the ON/OFF duration ratio of electric current was higher and as the period of ON/OFF cycle was shorter. The re-establishment of concentration polarization was dependent to the duration of current OFF state and, therefore, a longer duration of OFF state was not favorable in maintaining higher filtration flow rate. Although the averaged filtration flowrate was enhanced as the magnitude of electric current increased, the flowrate enhancement became smaller as the magnitude of current value above which the degree of electrokinetic depolarization is no further improved.

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A Study on the Reduction of Onboard Transformer Inrush Current of Electric Railway (전기철도 차량 내 변압기의 여자돌입전류 저감에 관한 연구)

  • Huh, Jae-Sun;Kang, Byoung-Wook;Shin, Hee-Sang;Kim, Jae-Chul
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.59 no.12
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    • pp.2125-2130
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    • 2010
  • The neutral section on electric railway system is significant sector in order to prevent short circuit of two electric powers. However, while electric trains pass the neutral section, those speed is decreased and the accident of AC electric traction system and the electric train would be occurred. So the countermeasures are urgently needed. The automatic power switching technology system that is current being research and development is system to improve these problems. Because main object of this system is power change using static switch in the neutral section, it's expected to cause a variety of transients. Especially, onboard transformer inrush current for electric railway train can be occurred more than rated current according to switching time. Therefore, the analysis and improvement are needed to ensure the stability of this system. In this paper, we analyze the operating characteristics of the automatic power switching technology system. Especially, it reviews inrush current according to the closing phase angle. And we propose control plan of inrush current considering the case that voltage is maintained due to counter electromotive force and regenerative braking operation of electric railway train. Finally, the proposed control scheme was reviewed using the transient analysis program.

Interruption Controller Design of Arc current With Custom Electric Source (아크의 방전에 따른 전기안전에 미치는 영향)

  • Ban, Gi-Jong;Lim, Seung-Ha;Won, Young-Jin
    • Proceedings of the IEEK Conference
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    • 2005.11a
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    • pp.1283-1286
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    • 2005
  • Arc Fault Current is an electric discharge which is occurred in two opposite electrode. In this paper, arc current control algorithm is designed for the interruption of arc fault current which is occurred in the local electric network. This arc is one of the main causes of electric fire. Arc fault in electrical network has the characteristics of low current, high impedance and high frequency. Conventional arc current controller does not have the arc current interrupt function. Hence, Controller of arc current is designed for the interruption of arc fault current which has the modified arc characteristics.

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