• Title/Summary/Keyword: current-effect

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Optical Current Snesor using Faraday Effect (Faraday 효과를 이용한 광 전류 센서)

  • 김수길
    • Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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    • 2002.11a
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    • pp.97-101
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    • 2002
  • The optical current transformer using Faraday effect is the sensor to measure current that flows in any conductor. This sensor doesn't undergo the magnetic saturation and effect of adjacent conductors. But this senor using bulk-glass sensing element has crucial drawback. It is impossible that the sensor is mounted to conductor without breaking the closed-loop of light or conductor. So we developed the clamp-type optical current transformer and made an experiment.

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An Effect of Drift Current on Generation Stage of Wind Waves (風波發생에 있어서 吹送流의 影響)

  • Choi, In june
    • 한국해양학회지
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    • v.19 no.2
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    • pp.195-199
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    • 1984
  • Effect of drift current on the first stage of wave generation by wind is studied theoretically. The viewpoint is similar to the one described by Phillips (1957) except that drift current is considered. It is found that inclusion of the effect of the drift current modifies significantly the results obtained by Phillips, particularly the resonance condition and wave spectrum.

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Considerations on the Performance of Current Sensorless Control of a Synchronous Reluctance Motor (동기릴럭턴스전동기의 전류센서리스 제어 성능 고찰)

  • Shin, Myoung-Ho
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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    • v.26 no.1
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    • pp.61-65
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    • 2012
  • Some works about the current sensorless control of a synchronous reluctance motor have been presented. However, there is no analysis about the performance and the detuning effect of the current sensorless control. This paper presents the problems and the detuning effect of the current sensorless control of a synchronous reluctance motor by simulation results. In addition, torque limiter is proposed to limit the torque current within the torque limit.

Characteristics of Wave Breaker and Longshore Current in the Surf Zone (쇄파특성과 쇄파대내의 연안류)

  • 김경호
    • Journal of Korean Society of Coastal and Ocean Engineers
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    • v.3 no.2
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    • pp.65-71
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    • 1991
  • Many investigations of wave deformation without currents have been carried out experimentally and theoretically but, studies treating the effect of longshore current on the wave deformation are few. It is thus necessary to evaluate the effect of longshore current on the wave deformation after breaking. In the paper the wave height attenuation. the wave direction and the variation of mean water level are calculated in which effects of longshore current are involved. To assess the effect of longshore current on the wave deformation, factors above with longshore current are compared with them without longshore current by using calculated results.

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A Study on the Leakage Current Voltage of Hybrid Type Thin Films Using a Dilute OTS Solution

  • Kim Hong-Bae;Oh Teresa
    • Journal of the Semiconductor & Display Technology
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    • v.5 no.1 s.14
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    • pp.21-25
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    • 2006
  • To improve the performance of organic thin film transistor, we investigated the properties of gate insulator's surface according to the leakage current by I-V measurement. The surface was treated by the dilute n-octadecyltrichlorosilane solution. The alkyl group of n-octadecyltrichlorosilane induced the electron tunneling and the electron tunneling current caused the breakdown at high electric field, consequently shifting the breakdown voltage. The 0.5% sample with an electron-rich group was found to have a large leakage current and a low barrier height because of the effect of an energy barrier lowered by, thermionic current, which is called the Schottky contact. The surface properties of the insulator were analyzed by I-V measurement using the effect of Poole-Frankel emission.

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Effect of Electric Current on Friction Characteristics of Machine Driving Elements (기계구동 부재의 마찰특성에 미치는 전류의 영향)

  • Jun, Sung-Jae;Cho, Yon-Sang;Park, Heung-Sik
    • Tribology and Lubricants
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    • v.18 no.5
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    • pp.339-344
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    • 2002
  • Whenever moving surfaces of machine driving elements interact in air and lubricating oil, oxidization film on the surfaces are generated. It is effect to prevent friction and wear on contact area. Since the electronic current progress the oxidization of metal, if the electronic flow be regulated, the thickness of oxidization film can be regulated and friction characteristics can be improved. But the electronic current can deteriorate friction characteristics, so various characteristics must be investigated on transforming of electronic current. Therefor, using the Norton equation in this study, short current were transformed between frictional materials using ball on disk type tester. It was studied on effect of electronic current for friction characteristics.

The Effect of Surface Recombination Current on the Saturation Current in Si Solar Cell (Si 태양전지(太陽電池)의 표면재결합(表面再結合) 전류(電流)가 포화전류(飽和電流)에 미치는 영향(影響))

  • Shin, Kee-Shik;Lee, Ki-Seon;Choi, Byung-Ho
    • Solar Energy
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    • v.8 no.2
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    • pp.12-18
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    • 1988
  • The effect of surface recombination current density on the saturation current density in Si solar cell has been studied. Theoretical model for surface recombination current was set up from emitter transparent model of M.A. Shibib, and saturation current of Si solar cell made by ion implantation method was also measured by digital electrometer. The theoretical surface recombination current density which is the same as saturation surface recombination current density in Shibib model was $10^{-11}[A/cm^2]$ and the measured value was ranged from $8{\times}10^{-10}$ to $2{\times}10^{-9}[A/cm^2]$. Comparing with the ideal p-n junction of Shockley, transparent emitter model shows improved result by $10^2$ order of saturation current density. But there still exists $10^2$ order of difference of saturation current density between theoretical and actual values, which are assumed to be caused by 1) leakage current through solar cell edge, 2) recombination of carriers in the depletion layer, 3) the series resistance effect and 4) the tunneling of carriers between states in the band gap.

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A Research on the Correct Concept of the Greenhouse Effect (온실 효과에 대한 바른 개념 고찰)

  • Shin Hyoun-Youn;Lee Du-Gon
    • Hwankyungkyoyuk
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    • v.19 no.2 s.30
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    • pp.122-132
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    • 2006
  • This research compared the mechanism of the greenhouse effect in the atmosphere with retaining warmth in the actual greenhouse, analyzed the styles of explaining the greenhouse effect in current textbooks, and investigated teachers' and students' degrees of understanding the effect. The mechanisms of the actual greenhouse and the greenhouse effect are not the same. Nevertheless, in all the current textbooks, the radiation phenomenon by the atmosphere is described as the 'greenhouse effect'. Using the words of the 'greenhouse effect' to refer to the effect of air being kept warm by the heat absorbing gases, causes confusion of concepts. To make learners understand the greenhouse effect exactly, concrete principles such as radiating electromagnetic phenomenon should be explained. However, teachers and current textbooks explained the radiating electromagnetic phenomenon as actual greenhouse. Therefore, it is difficult for learners to understand the greenhouse effect, scientifically. Because of this, learners maybe confused about greenhouse effect concepts.

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Electromagnetic effect by ignition current in vehicle (차량에서 Ignition current 변화에 따른 자기 유도에 의한 센서 출력 변화)

  • Lee, Dong-Ju;Kim, Cheol;Choe, Jang-Hyeon;Seong, Eun-Cheol
    • Proceedings of the KIEE Conference
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    • 2006.07c
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    • pp.1611-1612
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    • 2006
  • We are using the Faraday's electromagnetic law so as to improve our life in various industry fields. However, the side effect of the Faraday's law can be occurredin the sensors of the vehicle due to the high current flow such as Ignition. This effect is mainly caused by the shape of the wiring harness between sensor and high current load in the vehicle. To minimize the side effect by Faraday's law, three methods shall be considered in this paper (1) Pin definition of the sensor, (2) Pin definition of the high current load, (3) Wiring harness shape.

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Current Update on Transcranial Direct Current Stimulation as Treatment for Major Depressive Disorder (주요우울장애의 치료로서 경두개 직류자극술(Transcranial Direct Current Stimulation)의 현재)

  • Lee, Seung-Hoon;Kim, Yong-Ku
    • Korean Journal of Biological Psychiatry
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    • v.25 no.4
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    • pp.89-100
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    • 2018
  • Transcranial direct current stimulation (tDCS) is a non-invasive brain stimulation method that delivers 1-2 mA of current to the scalp. Several clinical studies have been conducted to confirm the therapeutic effect of major depressive disorder (MDD) patients with tDCS. Some studies have shown tDCS's antidepressant effect, while the others showed conflicting results in antidepressant effects. Our aim of this review is to understand the biological bases of tDCS's antidepressant effect and review the results of studies on tDCS's antidepressant effect. For the review and search process of MDD treatment using tDCS, the US National Library of Medicine search engine PubMed was used. In this review, we discuss the biological mechanism of tDCS's antidepressant effect and the existing published literature including meta-analysis, systematic review, control trial, open studies, and case reports of antidepressant effects and cognitive function improvement in patients with MDD are reviewed. We also discuss the appropriate tDCS protocol for MDD patients, factors predictive of response to tDCS treatment, the disadvantages of tDCS in MDD treatment, and side effects.

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