• 제목/요약/키워드: Relaxation current

검색결과 239건 처리시간 0.024초

인지질 유기단분자막의 알킬체인에 의한 유전완화시간 (Dielectric Relaxation Time for Alkyl Chain of Phospolipid Organic Monolayers Film)

  • 송진원;조수영;김영근;이경섭
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2004년도 춘계학술대회 논문집 반도체 재료 센서 박막재료 전자세라믹스
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    • pp.111-115
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    • 2004
  • In this paper, evaluation of physical properties about dielectric relaxation phenomena by the detection of the surface pressures and displacements current on the monolayer films of phospolipid monomolecular DLPC, DMPC using pressure stimulus. As a result, the changed surface pressure, displacement current and the transition forms of dipole moment of phospolipid monomolecular in area per molecular by pressure stimulus were conformed well. It was known that the monolayers by linear relationship for decision of dielectric relaxation time between compressure speed $\alpha$ and molecule area $A_m$ By according to the linear relationship relation get that frictional constant $\xi$, DLPC was $1.89{\times}10^{-19}$[Js] and DMPC was $0.722{\times}10^{-19}$[Js]. It is found that the phospolipid monolayer of dielectric relaxation takes a little time and depend on the molecular area.

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초전도 관내연선도체 접합부에서의 전류 불균일에 대한 수치적 분석 (Numerical analysis about current non-uniformity in superconducting CICC (cable-in-conduit conductor) joint)

  • 이상일;정상권;최성민;박갑래
    • 한국초전도ㆍ저온공학회논문지
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    • 제9권3호
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    • pp.41-45
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    • 2007
  • This paper presents transport current non-uniformity in a joint for superconducting multistage cable-in-conduit conductor (CICC) and relaxation in the CICC. The joint is considered to have a current loop linked to an external magnetic field so that it becomes an emf voltage source. It is numerically analyzed using an electrical transmission line model. The inductive current in a resistive joint is compared to that of a non-resistive joint when the ramping field is applied vertically to the joints. Regarding the parameter values of the model. a full scale $Nb_3Sn$ CICC and a strand-to-strand (STS) joint for the toroidal field magnet of the KSTAR (Korea Superconducting Tokamak Advanced Research) device are referenced to. It is found that the resistive joint prevents the current from rising too much and enhances decaying the current when the ramping stops. The 'flattop' current is found to be proportional to the ramp rate of the field (dB/dt). The relaxation length, which is defined as the length within which the maximum induced current falls by 1/e. is found to saturate within 0.27m.

DMPC 인지질 단분자막의 변위전류 특성 연구 (II) (A Study on Displacement Current Characteristics of DMPC Monolayer (II))

  • 송진원;이경섭;최용성
    • 전기학회논문지
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    • 제56권2호
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    • pp.343-348
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    • 2007
  • The physical properties of DMPC monolayer were made for dielectric relaxation phenomena by the detection of the surface pressures and displacements current. Lipid thin films were deposited by accumulation and the current was measured after the electric bias across the manufactured MIM device. It is found that the phospolipid monolayer of dielectric relaxation takes a little time and depend on the molecular area. When electric bias is applied across the manufactured MIM device by the deposition condition of phospolipid mono-layer, it wasn't breakdown when the higher electric field to impress by increase of deposition layers.

DMPC LB박막의 유전완화현상 (Dielectric Relaxation Phenomena of DMPC LB Thin Film)

  • 최영일;송진원;조수영;이경섭
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2003년도 하계학술대회 논문집 Vol.4 No.2
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    • pp.822-825
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    • 2003
  • Maxwell displacement current (MDC) measurement has been employed to study the dielectric property of Langmuir-films. A method for determining the dielectric relaxation time $\tau$ of floating monolayers on water surface is presented. WC flowing across monolayers is analyzed using a rod-like molecular model. It is revealed that the dielectric relaxation time $\tau$ of monolayers in the isotropic polar orientational phase is determined using a liner relationship between the monolayer compression speed ${\alpha}$ and the molecular area Am. Compression speed ${\alpha}$ was about 30, 40, 50mm/min.

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장쇄지방산 L막의 완화 시간 (Dielectric Relaxation Time of Long Chain Fatty Acid Langmuir films)

  • 전동규;장헌;오재한;강용철;최영일;이경섭
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2000년도 추계학술대회 논문집
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    • pp.279-282
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    • 2000
  • The displacement current measurement has been employed to study the dielectric properties of Langmuir films. A method for determining the dielectric relaxation time $\tau$ of floating monolayers on water surface is presented. The displacement current flowing across monolayers is analyzed using a rod-like molecular model. It's revealed that the dielectric relaxation time $\tau$ of monolayers in the isotropic polar orientational phase is determined using a liner relationship between the monolayers compression speed $\alpha$ and the molecular maximum area $A_{m}$. The compression speed $\alpha$ was about 30, 40, 50mm/minmm/min

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접근해법을 이용한 열자격전류의 활성화에너지 오차 보정 (Error Correction of the Activation Energy of Thermally Stimulated Current by using a Asymptotic Estimation Method)

  • 김기준;박승협;김충혁;이준응
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 1992년도 추계학술대회 논문집
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    • pp.118-122
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    • 1992
  • In this paper, the properties of Thermally Stimulated Current was studied to understand carrier's behavior of $PVF_2$ film, to be regarded as the excellent piezo and pyroelectricity. The complex relaxation curve of Thermally Stimulated Current was divided into single relaxation style using Thermal Cleaning method. As a result of Applying the numerical method of asymtotic estimation to the divided single relaxation peak, we could calculated the physical factors related to charged particles of the specimen, more accurately.

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RF 스퍼터링법에 의한 SCT 박막의 Sr/Ca 비율 영향 (Effects of Sr/Ca Ratio of SCT thin film by RF Sputtering Method)

  • 김진사;오용철
    • 반도체디스플레이기술학회지
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    • 제5권4호
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    • pp.5-9
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    • 2006
  • The SCT thin films are deposited on Pt-coated electrode($Pt/TiN/SiO_2/Si$) using RF sputtering method with Sr/Ca ratio. The maximum grain of thin films is obtained by ratio of Ca at 15 mol%. The dielectric constant was increased with increasing the ratio of Ca, while it was decreased if the ratio of Ca exceeded over 15 mol%. The dielectric constant changes almost linearly in temperature ranges of $-80{\sim}+90$. All SCT thin films used in this study show the phenomena of dielectric relaxation with the increase of frequency, and the relaxation frequency is observed above 200 kHz. The current-voltage characteristics of SCT thin films showed the increasing leakage current as the measuring temperature increases.

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Non Stationary Ionic Current through Polymer Charged Membrane

  • Jeong, Sung-Hyun;Lee, Won-Chul;Yang, Wong-Kang
    • Bulletin of the Korean Chemical Society
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    • 제24권7호
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    • pp.937-942
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    • 2003
  • The relaxation phenomena of ionic currents through the charged membrane under the constant applied potentials has been studied. The formulation was obtained for the non stationary current by assuming that the ion mobility is independent of concentration and the potential gradient is a constant within membrane, and it was applied to the experimental results with the sulfonated polystyrene collodion base membrane. It has been shown that the initial ion distributions in the membrane play a predominant role in the relaxation phenomena.

전력용 소자 제작을 위한 유기박막 전기물성에 관한 연구 (A Study on the Electrical Physical Properties of Organic Thin Films for Manufacture in Power Device)

  • 조수영;김영근;최영일;송진원;이경섭
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2004년도 춘계학술대회 논문집
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    • pp.37-41
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    • 2004
  • In this paper, evaluation of physical properties about dielectric relaxation phenomena by the detection of the surface pressures and displacements current on the monolayer films of phospolipid monomolecular DLPC, DMPC using pressure stimulus. As a result, the changed surface pressure, displacement current and the transition forms of dipole moment of phospolipid monomolecular in area per molecular by pressure stimulus were conformed well. It was known that the monolayers by linear relationship for decision of dielectric relaxation time between compressure speed and molecule area By according to the linear relationship relation get that frictional constant, DLPC was $1.89{\times}10^{-19}$ [Js] and DMPC was $0.722{\times}10^{-19}$[Js]. lt is found that the phospolipid monolayer of dielectric relaxation takes a little time and depend on the molecular area.

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에폭시 복합재료의 열자격전류(TSC) 특성: - 경화제와 충진제의 영향 (The Characteristics of Termally Stimulated Current for Epoxy Composites : The effects of Curing Agents and Fillers)

  • 왕종배;박준범;이준웅;김홍철
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1993년도 하계학술대회 논문집 B
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    • pp.1162-1164
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    • 1993
  • The Thermally Stimulated Current(TSC) spectroscopy has been applied to study the influence of the structual cahange and interface on the electrical properties of epoxy composites. Three DGEBA-MeTHPA matrix model samples mixed different ratios and silica($SiO_2$) filled sample and silaln treating-filled sample has been studied. Above room temperature, the relaxation mode $\alpha$ peak associated with Tg has been located at $110^{\circ}C$. Below glass transition temperature(Tg), three relaxation modes are observed in all samples: a $\beta$ mode situated at $10^{\circ}C$, a $\gamma$ mode located at $-40^{\circ}C$ and a $\delta$ mode appeared in $-120^{\circ}C$. The analysis of its fine structure indicates that constitution of elementary processes is characterized by the activation energy and relaxation time. Also the dielectric relaxation properties have been investigated to compare the the change of the molecular structure and motion to the relaxation properties and conduction mechanism in TSC spectra.

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