• 제목/요약/키워드: transport characteristic

검색결과 379건 처리시간 0.029초

적층 수에 따른 YBCO 선재의 전송전류 손실 특성 (Characteristic of Transport Current Losses of Multi-Stacked YBCO Coated Conductors)

  • 한병욱;임희현;강명훈;임형우;차귀수;이희준
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2006년도 제37회 하계학술대회 논문집 A
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    • pp.599-600
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    • 2006
  • Multi-slacked HTS tapes are needed to conduct large current in the power application of superconducting machine. This paper deals with the transport current loss of multi-stacked YBCO coated conductor. YBCO coated conductor that was used in this experiment has two Cu layers above and below of YBCO layer for stabilization. Transport losses of four different stacks, single, 2 stack, 3 stack and 4 stack, were measured. Measured results were compared analytic equation suggested by Norris.

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적층 수에 따른 YBCO 선재의 전송전류 손실 특성 (Characteristic of Transport Current Losses of Multi-Stacked YBCO Coated Conductors)

  • 한병욱;임희현;강명훈;임형우;차귀수;이희준
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2006년도 제37회 하계학술대회 논문집 D
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    • pp.2231-2232
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    • 2006
  • Multi-stacked HTS tapes are needed to conduct large current in the power application of superconducting machine. This paper deals with the transport current loss of multi-stacked YBCO coated conductor. YBCO coated conductor that was used in this experiment has two Cu layers above and below of YBCO layer for stabilization. Transport losses of four different stacks, single, 2 stack, 3 stack and 4 stack, were measured. Measured results were compared analytic equation suggested by Norris.

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Effects of Thermal-Carrier Heat Conduction upon the Carrier Transport and the Drain Current Characteristics of Submicron GaAs MESFETs

  • Jyegal, Jang
    • 한국산업정보학회:학술대회논문집
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    • 한국산업정보학회 1997년도 추계학술대회 발표논문집:21세기를 향한 정보통신 기술의 전망
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    • pp.451-462
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    • 1997
  • A 2-dimensional numerical analysis is presented for thermal-electron heat conduction effects upon the electron transport and the drain current-voltage characteristics of submicron GaAs MESFETs, based on the use of a nonstationary hydrodynamic transport model. It is shown that for submicron GaAs MESFETs, electron heat conduction effects are significant on their internal electronic properties and also drain current-voltage characteristics. Due to electron heat conduction effects, the electron energy is greatly one-djmensionalized over the entire device region. Also, the drain current decreases continuously with increasing thermal conductivity in the saturation region of large drain voltages above 1 V. However, the opposite trend is observed in the linear region of small drain voltages below 1 V. Accordingly, for a large thermal conductivity, negative differential resistance drain current characteristics are observed with a pronounced peak of current at the drain voltage of 1 V. On the contrary, for zero thermal conductivity, a Gunn oscillation characteristic is observed at drain voltages above 2 V under a zero gate bias condition.

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수송전류에 따른 Bi-2223 선재의 특성연구 (The characteristic research of a Bi-2223 wires by the Various Transport Current)

  • 오정훈;배덕권;강형구;안민철;이상진;고태국
    • 한국초전도저온공학회:학술대회논문집
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    • 한국초전도저온공학회 2003년도 학술대회 논문집
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    • pp.220-223
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    • 2003
  • High-Tc superconducting(HT S) systems are commercialized by many study on high-Tc superconductor. For the successful commercialization of superconducting systems using Bi-2223 wires, the database on the degradation of critical current is essentially needed. In this paper, critical current variation of Bi-2223 wires according to the transport time was investigated. The degradation rate of critical current was also calculated. Solenoid type specimens have the length of 190cm Bi-2223 wire and double-pancake type specimens have the length of l0m wire were tested. Tested Bi-2223 wires are commercialized products of AMSC (American Superconductor) and Innost. When the transportation current was 95% of critical current, the degradation of critical current was appeared after 5 hours of transport time.

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2항근사 볼츠만 방정식을 이용한 Xe분자가스의 전자수송계수의 해석 (The study of electron transport coefficients in pure Xe by 2-term approximation of the Boltzmann equation)

  • 마수영;전병훈;김송강
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2001년도 춘계학술대회 논문집 유기절연재료 전자세라믹 방전플라즈마 연구회
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    • pp.174-177
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    • 2001
  • The electron transport coefficients, the electron drift velocity W, the longitudinal diffusion coefficient $ND_L$ and $D_L/{\mu}$, in pure Xe were calculated over the wide E/N range from 0.01 to 500 Td at 1 Torr by two-term approximation of the Boltzmann equation for determination of electron collision cross sections set and for quantitative characteristic analysis of Xe molecular gas.

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2항근사 볼츠만 방정식을 이용한 Ne분자가스의 전자수송계수의 해석 (The study of electron transport coefficients in pure Ne by 2-term approximation of the Boltzmann equation)

  • 전병훈;강명희;김송강
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2001년도 춘계학술대회 논문집 유기절연재료 전자세라믹 방전플라즈마 연구회
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    • pp.182-185
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    • 2001
  • The electron transport coefficients, the electron drift velocity W, the longitudinal diffusion coefficient $ND_L$ and $D_L/{\mu}$, in pure Ne were calculated over the wide E/N range from 0.01 to 300 Td at 1 Torr by two-term approximation of the Boltzmann equation for determination of electron collision cross sections set and for quantitative characteristic analysis of Ne molecular gas.

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적층 수에 따른 YBCO 선재의 전송전류 손실 특성 (Characteristic of Transport Current Losses of Multi-Stacked YBCO Coated Conductors)

  • 한병욱;임희현;강명훈;임형우;차귀수;이희준
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2006년도 제37회 하계학술대회 논문집 B
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    • pp.1265-1266
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    • 2006
  • Multi-stacked HTS tapes are needed to conduct large current in the power application of superconducting machine. This paper deals with the transport current loss of multi-stacked YBCO coated conductor. YBCO coated conductor that was used in this experiment has two Cu layers above and below of YBCO layer for stabilization. Transport losses of four different stacks, single, 2 stack, 3 stack and 4 stack, were measured. Measured results were compared analytic equation suggested by Norris.

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적층 수에 따른 YBCO 선재의 전송전류 손실 특성 (Characteristic of Transport Current Losses of Multi-Stacked YBCO Coated Conductors)

  • 한병욱;임희현;강명훈;임형우;차귀수;이희준
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2006년도 제37회 하계학술대회 논문집 C
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    • pp.1725-1726
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    • 2006
  • Multi-stacked HTS tapes are needed to conduct large current in the power application of superconducting machine. This paper deals with the transport current loss of multi-stacked YBCO coated conductor. YBCO coated conductor that was used in this experiment has two Cu layers above and below of YBCO layer for stabilization. Transport losses of four different stacks, single, 2 stack, 3 stack and 4 stack, were measured. Measured results were compared analytic equation suggested by Norris.

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Preferential 흐름에 의한 토양내의 다영역 용질이동 모델 (Multi-Region Model of Solute Transport in Soil for the Preferential Flow)

  • 안병기
    • 한국농공학회지
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    • 제42권2호
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    • pp.71-77
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    • 2000
  • A multi-region model for solute transport through saturated soils has been developed to describe preferential flow. The model consists of numerous discrete pore groups, which are characterized by a discrete dispersion coefficient, flow velocity, and porosity . The hydraulic properties for each pore group are derived from a soil's hydraluic conductivity and soil water characteristic functions . Flow in pore group is described by the classical advection-disersion equation (ADE). An implict finite difference scheme was applied to the governing equation that results in a block-tridiagonal system of equations that is very efficient and allows the soil to be divided into any number of pore groups. The numerical technique is derived from methods used to solve coupled equations in fluid dynamics problems and can also be applied to the transport of interacting solutes. The results of the model are compared to the experimental data from published papers. This paper contributes on the characteristics of the method when applied to the parallel porosity model to describe preferential flow of solutes in soil.

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