• 제목/요약/키워드: inductive

검색결과 1,466건 처리시간 0.024초

초전도 선재 조합에 따른 비대칭 무유도성 코일의 교류 손실 특성 연구 (A Study on AC loss Characteristics of Asymmetric non-inductive coils with Combination of Superconducting wires)

  • 김진섭;황영진;나진배;최석진;김영재;이지호;이우승;장기성;고태국
    • 한국초전도ㆍ저온공학회논문지
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    • 제13권1호
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    • pp.17-21
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    • 2011
  • A hybrid superconducting fault current limiter (SFCL) with fast switch had been previously suggested by our research group. To make a hybrid SFCL, different superconducting wires were wound two pancake coils so that two pancake coils had asymmetric configuration. The impedance of the asymmetric non-inductive coils are zero with applied normal current. However during the fault. currents were distributed unequally into the two pancake coils because each superconducting wires have different electrical characteristics. This unequal distribution of current causes effective magnetic flux which generate repulsive force. Fast switch was thus opened by the force applied to the aluminum plate which consists of SFCL. In this paper, the AC loss characteristics of the asymmetric non-inductive coils with combinations of superconducting wires were studied and calculated by related experiments and finite element method (FEM) simulation. From these results, we suggested the appropriate combination of two superconducting wires to be used for the asymmetric non-inductive coils.

AT급전방식에서 AT간격에 따른 전압강하 및 대지누설전류에 대한 연구 (A Study on the Voltage Drop and Earth Leakage Current according to Interval of AT in the AT Feeding Method)

  • 김민석;최승혁;이종우
    • 전기학회논문지
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    • 제60권9호
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    • pp.1708-1714
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    • 2011
  • AT feeding system of the electric railway system is installed every about 10km at between the feeder and catenary in parallel and the mid-point of the transformer is connected to the rail The supply voltage of this system is doubled than rolling stock voltage. So the voltage drop is smaller than usual. And the other merit of this system is the decreasing inductive disturbance to the communication line because of the reduced current in rail which runs reversed in a point of view of rolling stock. Also, ATP(Auto Transformer Post) is installed to reduce the voltage drop and to mitigate the inductive disturbance, but still now the proper distance between the ATP and AT feeding system is not established which ranges from 2 to 10[km]. The stable result of simulation(which is set that the end of the line AT is installed) to the voltage drop and inductive disturbance can not analyzes the effect to the supply system due to the ATP. This paper analyzes the effect to the system depending on the location of ATP by forecasting the voltage drop and inductive disturbance.

Photoperiodic Floral Induction in Pharbitis Cotyledons Affected by Polyamines and Ethylene

  • Jueson Maeng
    • Journal of Plant Biology
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    • 제38권3호
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    • pp.227-234
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    • 1995
  • Exogenous putrescine of 0.5 mM or higher concentratons applied during a 16 h inductive dark period could elevate putrescine content in cotyledons of Pharbitis nil Choisy cv. Violet, a short-day plant, resulting in complete blocking of photoperiodic floral induction. Titers of putrescine, spermidine and spermine in the cotyledons were traced throughout a 16 h dark period. While non-induced cotyledons under continous light slightly increased levels of polyamines, induced tissue maintaiend its putrescine, spermidine and spermine levels as low as 66.4%, 60.9% and 84.9% of non-induced levels respecitvely. Endogenous polyamines kept at lower levels in the inductive dark period were found to upsurge by a night break treatment of 10 min light in the middle of the dark and consequently the inductive dark effect was canceled. Elevation of polyamine titers could also be induced by 100 $\mu$L/L ethylene treatment which completely suppressed floral induction. Compared to untreated cotyledons, ehtylene-treated tissues increased putrescine content by as much as 136.5% in 12 h and spermidine level by up to 130.1% in 8 h. Ethylene-treated cotyledons not only increased endogenous polyamine content but also liberate ethylene in the second half of the inductive dark period accumulating up to three to fourfold level supporting a hypothesis that ethylene-treated tissues are stimulated to produce ethylene which in turn accelerates polyamine biosynthesis in the tissues. It is postulated that substantially low polyamine titers in the inductive dark period would be one of the necessary factors controlling photoperiodic induction of flowering in Pharbitis nil and the inhibitory effects of night break and exogenous ethylene treatment may be atributed to their action to stimulate endogenous polyamine production.

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Study on quench detection of the KSTAR CS coil with CDA+MIK compensation of inductive voltages

  • An, Seok Chan;Kim, Jinsub;Ko, Tae Kuk;Chu, Yong
    • 한국초전도ㆍ저온공학회논문지
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    • 제18권1호
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    • pp.55-58
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    • 2016
  • Quench Detection System (QDS) is essential to guarantee the stable operation of the Korea Superconducting Tokamak Advanced Research (KSTAR) Poloidal Field (PF) magnet system because the stored energy in the magnet system is very large. For the fast response, voltage-based QDS has been used. Co-wound voltage sensors and balanced bridge circuits were applied to eliminate the inductive voltages generated during the plasma operation. However, as the inductive voltages are hundreds times higher than the quench detection voltage during the pulse-current operation, Central Difference Averaging (CDA) and MIK, where I and K stand for mutual coupling indexes of different circuits, which is an active cancellation of mutually generated voltages have been suggested and studied. In this paper, the CDA and MIK technique were applied to the KSTAR magnet for PF magnet quench detection. The calculated inductive voltages from the MIK and measured voltages from the CDA circuits were compared to eliminate the inductive voltages at result signals.

귀납추론에 토대한 직설법적 조건문 (Indicative Conditionals Based on Inductive Reasoning)

  • 이병덕
    • 논리연구
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    • 제17권1호
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    • pp.197-217
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    • 2014
  • 필자는 이전의 여러 논문들에서 이른바 '논란 없는 원리'가 귀납 추론에 토대한 직설법적 조건문과 관련하여 성립하지 않음을 주장했다. 왜냐하면 귀납추론에 토대한 직설법적 조건문 '$A{\rightarrow}_iC$'가 질료적 조건문 '$A{\supset}C$'를 논리적으로 함축함을 받아들이면, 'A'라는 가정 하에서 'C'를 단언적으로 주장하는 경우와 단지 'C'가 참일 개연성이 높음을 주장하는 경우를 구분할 수 없게 되는 부조리한 결과가 발생하기 때문이다. 그러나 양은석 교수는 그의 최근 논문 "논란 없는 원리와 귀납논증"에서 논란 없는 원리에 관한 필자의 주장이 성공적이지 않다고 비판한다. 이 논문에서 필자는 양 교수의 비판이 필자의 논점과 무관함을 주장한다.

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RF 유도형 플라즈마 프로세스에 대한 분광학적 연구 (A Study on the Optical Emission Spectroscopy of the RF Inductive Plasma Process)

  • 장문국;한상보;박상현
    • 조명전기설비학회논문지
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    • 제25권11호
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    • pp.103-112
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    • 2011
  • This paper is tried to analysis the optical emission spectroscopy related to the position of inductive load coil and flow rates of methane and oxygen in the RF inductive plasma process. According to the position of load coil, peak of $H_{\alpha}$, $H_{\beta}$, and CH were appeared strongly at the middle position of the coil and it decreased both direction. The electron temperature was approximately 0.9[eV] at that position. Emission intensities of $H_{\alpha}$, $H_{\beta}$, and CH increased linearly by increasing input power. In addition, intensities of $H_{\alpha}$ and $H_{\beta}$ increased by increasing the flow rate of oxygen. It might be ascribed that the oxygen species were bonded with $C_nH_m$ by suppressing the combination with hydrogen atoms. Consequently, the optimal position of the inductive coil is decided to the intermediate position between 4th and 5th turns, the wanted carbon thin-film is possible to deposit by controlling flow rates of methane and oxygen.

유도성 아이리스를 이용한 NRD 가이드 필터의 설계 및 제작 (Design and Fabrication of NRD Guide Filter using Inductive Iris)

  • 김영수;류원렬;최형동;유영근
    • 한국전자파학회논문지
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    • 제13권8호
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    • pp.741-747
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    • 2002
  • 본 논문에서는 WRD 가이드를 이용하여 38 MHz 밀리미터파 대역의 대역통과 필터를 설계하고, 실제 제작하여 그 측정 결과를 비교 분석하였다. 기존의 공극 결합된 NRD 가이드 필터의 경우, NRD 가이드로 사용되는 PTFE 선로의 정밀 가공 및 공진기 간의 정위치가 어려워 대량생산에 불리한 단점이 있었으나, 본 연구에서는 각각의 유전체 공진기를 Inductive Iris로 결합, 하나의 선로상에 공진기를 제작할 수 있으므로 가공 및 조립성이 뛰어나 양산에 적합한 구조를 갖는다. 설계 한 필터는 측정 결과, 통과대역 38.66 - 39.06 MHz로 400 MHz 대역폭을 가지며, 대역내 삽입손실 1.4 dB, 반사손실 -18 dB 이하의 우수한 특성을 갖는다.

차량용 유도전력 집전 장치의 특성해석 (The Modeling of inductive power collector for vehicle)

  • 한경희;이병송;김도원;백수현
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2005년도 제36회 하계학술대회 논문집 B
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    • pp.1610-1612
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    • 2005
  • In this paper, the inductive power collector using electromagnetic induction for vehicle such as the PRT(Personal Rapid Transit) system is suggested and some ideas for power collector design to improve the power transfer performance are presented. The proposed the inductive power collector is used for the PRT system, which has a large air-gap and demands a large electrical power capability. But, low output power is generated due to a loosely coupled characteristic of the large air-gap. Therefore, double layer construction of secondary winding, which was divided in half to increase both output current and output voltage was suggested. Also, a model of power collector and parallel winding structure and a model of concentration/decentralization winding are presented, in addition, the performance of inductive power collector to alignment condition between the primary power line and the inductive power transformer was verified by computer simulation of 2kW model.

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초전도 전류 발전기의 유도리액턴스 손실에 관항 연구 (A Study on the Analysis of the Inductive Reactance Losses of a Superconducting Current Generator)

  • Ko, Tae-Kuk
    • 대한전기학회논문지
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    • 제39권12호
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    • pp.1317-1320
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    • 1990
  • The inductive reactance losses of a superconducting current generator built at Case Western Reserve University has been analyzed. The calculations of the field in the spot make it possible to estimate the spot inductance as well as the filament inductance on the foil. It is shown that magnetic energy lost in switching the current is mainly due to the amplitude of the fluctuation in voltage associated with the inductive reactance losses of a superconducting current generator.

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유도형 변위 센서의 동적 특성 향상을 위한 이론적 고찰 (A Theoretical Investigation for Improving Dynamic Characteristics of Inductive position sensor)

  • 신우철;홍준희;이동주
    • 한국공작기계학회:학술대회논문집
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    • 한국공작기계학회 2002년도 춘계학술대회 논문집
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    • pp.149-154
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    • 2002
  • In a high speed spindle system, it is very important to monitor the state of rotating rotor. Particularly in active control spindle system, the position sensor must provide feedback to the control system on the exact position of the rotor. In order to monitor the state of a high speed spindle exactly, high accuracy and wide frequency bandwidth of sensors are important. This paper observes the factors which has an effect on dynamic performances of inductive position sensor.

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