• 제목/요약/키워드: AR approximation

검색결과 44건 처리시간 0.019초

시뮬레이션에 의한 CF4, CH4, Ar혼합기체(混合氣體)에서 전자(電子)에너지분포함수 (A Simulation of the Energy Distribution Function for Electron in CF4, CH4, Ar Gas Mixtures)

  • 김상남
    • 전기학회논문지P
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    • 제52권1호
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    • pp.9-13
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    • 2003
  • Energy Distribution Function in pure $CH_4$, $CF_4$ and mixtures of $CF_4$ and Ar, have been analyzed over a range of the reduced electric field strength between 0.1 and 350[Td] by the two-term approximation of the Boltzmann equation (BEq.) method and the Monte Carlo simulation (MCS). The results of the Boltzmann equation and the Monte Carlo simulation have been compared with the data presented by several workers. The deduced transport coefficients for electrons agree reasonably well with the experimental and simulation data obtained by Nakamura and Hayashi. The energy distribution function of electrons in $CF_4-Ar$ mixtures shows the Maxwellian distribution for energy. That is, $f(\varepsilon)$ has the symmetrical shape whose axis of symmetry is a most probably energy. The measured results and the calculated results have been compared each other.

CF4, CH4, Ar 혼합기체의 전자이동속도 (The Drift Velocity of Electrons in CF4, CH4, Ar Mixtures Gas)

  • 김상남
    • 전기학회논문지P
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    • 제60권3호
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    • pp.105-109
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    • 2011
  • Drift Velocity of Electrons in pure $CF_4$, $CH_4$ and mixtures of $CF_4$ and Ar. Have been analyzed over a range of the reduced electric field strength between 0.1 and 350[Td] by the two-term approximation of the Boltzmann equation (BEq.) method and the Monte Carlo simulation (MCS). The results of the Boltzmann equation and the Monte Carlo simulation have been compared with the data presented by several workers. The deduced transport coefficients for electrons agree reasonably well with the experimental and simulation data obtained by Nakamura and Hayashi. The energy distribution function of electrons in $CF_4$-Ar mixtures shows the Maxwellian distribution for energy. That is, f(${\varepsilon}$) has the symmetrical shape whose axis of symmetry is a most probably energy. The measured results and the calculated results have been compared each other.

볼츠만방정식과 몬테칼로법에 의한 $SiH_4$-Ar 혼합가스의 전자수송계수에 관한 연구 (The Study of Electron Transport coefficients in $SiH_4$-Ar Mixtures by Using Boltzmann Equation Analysis and Monte-Carlo Simulation)

  • 하성철;전병훈
    • 한국전기전자재료학회논문지
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    • 제14권2호
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    • pp.169-174
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    • 2001
  • The electron transport coefficients(the electron drift velocity, W, and the longitudinal and transverse diffusion coefficient, D$_{L}$ and D$_{T}$) in SiH$_4$-Ar mixtures containing 0.5% and 5.0% monosilane were calculated over the E/N range from 0.01 to 300 Td and over the gas pressure range 0.5, 1.0 and 1.5 Torr by the time-of-flight(TOF) method of the Boltzmann equation(BE.) and Monte-Carlo simulation(MCS). The electron energy distribution function in each SiH$_4$-Ar mixtures at E/N=10 Td and L=0.2 cm, which in equilibrium region in the mean electron enregy were compared.red.

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TOF법에 의한 $CF_4+Ar$ 혼합기체의 전자수송특성 해석 (Analysis of electron transport properties of $CF_4+Ar$ mixtures gas by the TOF method)

  • 서상현;하성철;유회영
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 1998년도 춘계학술대회 논문집
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    • pp.279-283
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    • 1998
  • The electron swarm parameters in the$CF_4$(O.l%, 5%)+Ar mixtures are measured by time of flight method over the E/N(Td) range from 10 to 300LTdl. A two-term approximation of the Boltzmann equation analysis and Monte Carlo simulation have been also used to study electron transport coefficients. We have calculated W, NDL, NDT, $\alpha$ and the limiting breakdown electric field to gas mixtures ratio in pure $CF_4$ gas and$CF_4+Ar$ mixtures. The measured results and the calculated results have been compared each other paper.

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CF4, CH4, Ar 혼합기체의 전자 평균에너지 (Electron Mean Energy in CF4, CH4, Ar mixtures)

  • 김상남
    • 전기학회논문지P
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    • 제64권4호
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    • pp.241-245
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    • 2015
  • Energy Distribution Function in pure $CH_4$, $CF_4$ and mixtures of $CF_4$ and Ar, have been analyzed over a range of the reduced electric field strength between 0.1 and 350[Td] by the two-term approximation of the Boltzmann equation (BEq.) method and the Monte Carlo simulation (MCS). The calculations of electron swarm parameters require the knowledge of several collision cross-sections of electron beam. Thus, published momentum transfer, ionization, vibration, attachment, electronic excitation, and dissociation cross-sections of electrons for $CH_4$, $CF_4$ and Ar, were used. The differences of the transport coefficients of electrons in $CH_4$, mixtures of $CH_4$ and Ar, have been explained by the deduced energy distribution functions for electrons and the complete collision cross-sections for electrons. The results of the Boltzmann equation and the Monte Carlo simulation have been compared with the data presented by several workers. The deduced transport coefficients for electrons agree reasonably well with the experimental and simulation data obtained by Nakamura and Hayashi. The energy distribution function of electrons in $CF_4$-Ar mixtures shows the Maxwellian distribution for energy. That is, $f({\varepsilon})$ has the symmetrical shape whose axis of symmetry is a most probably energy.

AR 모델을 이용한 전기자극에 대한 근신호 M -wave의 정보압축 (Inoformation Compression of Myoelectric M-wave Evoked by Electrical Stimulus using AR Model)

  • 김덕영;박종환;김성환
    • 대한의용생체공학회:의공학회지
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    • 제20권3호
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    • pp.307-314
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    • 1999
  • M-wave 는 신경전도 연구에 있어서 후기반응 현상 중 직접적인 반응으로, 반응 후 일정시간내에 정보가 존재하는 단발 반응의 특성을 가지고 있다. 이러한 M-wave 는 신경계통의 질환을 진단하기 위한 유용한 요소이며, 따라서 M-wave 의 형태 및 시간에 관한 정보가 간단히 표현될 수 있다면 신경질환 연구에 많은 도움이 될 것이다. 따라서 본 연구에서는 Ar 모델링 방법이 이러한 M-wave 의 정보 압축에 있어서 효과적임을 증명하였다. 이로 인해 먼저 실제로 측정된 M-wave 신호에서 Ar 파라메터를 추정하였으며, 추정된 파라메터를 가지고 근사화한 곡선과 최근의 M-wave의 정보압축에 관한 연구인 Hermite 변환을 이용한 방법에 따른 근사화 곡선을 비교하였다. 제안된 방법의 구체적인 검증을 위해 실신호와 근사화 곡선의 정규화 평균자승오차(NMSE)를 구하여 비교하였다. 결론적으로 M-wave 의 정보를 압축하는데 있어 Hermite 변환은 30개의 파라메터가 필요한 반면, 본 연구에서 제시한 AR 모델링방법은 3개의 파라메터만 가지고도 효과적으로 M-wave 의 특징을 압축할 수 있음을 보였다.

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CF4, CH4, Ar 혼합기체의 전리와 부착계수 (Ionization and Attachment Coefficients in CF4, CH4, Ar Mixtures Gas)

  • 김상남
    • 전기학회논문지P
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    • 제61권1호
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    • pp.13-17
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    • 2012
  • Ionization and Attachment Coefficients in pure $CH_4$, $CF_4$ and mixtures of $CF_4$ and Ar, have been analyzed over a range of the reduced electric field strength between 0.1 and 350[Td] by the two-term approximation of the Boltzmann equation (BEq.) method and the Monte Carlo simulation (MCS). The calculations of electron swarm parameters require the knowledge of several collision cross-sections of electron beam. Thus, published momentum transfer, ionization, vibration, attachment, electronic excitation, and dissociation cross-sections of electrons for $CH_4$, $CF_4$ and Ar, were used. The results of the Boltzmann equation and the Monte Carlo simulation have been compared with the data presented by several workers. The deduced transport coefficients for electrons agree reasonably well with the experimental and simulation data obtained by Nakamura and Hayashi. The energy distribution function of electrons in $CF_4$-Ar mixtures shows the Maxwellian distribution for energy. That is, f(${\varepsilon}$) has the symmetrical shape whose axis of symmetry is a most probably energy. The proposed theoretical simulation techniques in this work will be useful to predict the fundamental process of charged particles and the breakdown properties of gas mixtures.

$SiH_4-Ar$ 혼합기체의 평균 에너지에 관한 연구 (Analysis of the Mean Energy in $SiH_4-Ar$ Mixture Gases)

  • 김상남
    • 전기학회논문지P
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    • 제55권2호
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    • pp.57-61
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    • 2006
  • This paper calculates and gives the analysis of mean energy in pure $SiH_4,\;Ar-SiH_4$ mixture gases ($SiH_4-0.5[%],\;5[%]$) over the range of $E/N =0.01{\sim}300[Td]$, p = 0.1, 1, 5.0 [Torr] by Monte Carlo the Backward prolongation method of the Boltzmann equation using computer simulation without using expensive equipment. The results have been obtained by using the electron collision cross sections by TOF, PT, SST sampling, compared with the experimental data determined by the other author. It also proved the reliability of the electron collision cross sections and shows the practical values of computer simulation. The calculations of electron swarm parameters require the knowledge of several collision cross-sections of electron beam. Thus, published momentum transfer, ionization, vibration, attachment, electronic excitation, and dissociation cross-sections of electrons for $SiH_4$ and Ar, were used. The differences of the transport coefficients of electrons in $SiH_4$, mixtures of $SiH_4$ and Ar, have been explained by the deduced energy distribution functions for electrons and the complete collision cross-sections for electrons. A two-term approximation of the Boltzmann equation analysis and Monte Carlo simulation have been used to study electron transport coefficients.

$SF_{6+}Ar$혼합기체의 전자수송특성 개선에 관한 연구 (A Study on the Improvement of the Electron Transport Properties in $SF_{6+}Ar$ Mixtures Gas)

  • 하성철;김상남;유회영;서상현;임상원;전병훈
    • 한국전기전자재료학회논문지
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    • 제11권1호
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    • pp.67-73
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    • 1998
  • In this paper, the electron swarm parameters in the 0.5% and 0.2% SF\ulcorner+Ar mixtures are measured by time of flight method over the E/N(Td) range from 30 to 300(Td). The measurements have been carried out by the double shutter drift tube with variable drift distance from the cathod. A two-term approximation of the boltzmann equation analysis and Monte Carlo simulation have been also used to study electron transport coefficients. We have calculated W, $ND_L,\;ND_T,\;\alpha,\;\eta,\;\alpha-\eta$, and the limiting breakdown electric field to gas mixtures ratio in pure $SF_6$+Ar mixtures. The electron energy distribution function has been analysed in $SF_6$+Ar mixtures at E/N : 200(Td) for a case of the equilibrium region in the mean electron energy. The measured results and the calculated results have been compared each other.

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Kalman filter를 이용한 생체신호의 AR modelling (AR modelling for a biomedical signal using Kalman filter)

  • 김대근;박해정;지영준;박광석;이충웅
    • 대한의용생체공학회:학술대회논문집
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    • 대한의용생체공학회 1997년도 춘계학술대회
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    • pp.184-187
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    • 1997
  • In terms of a system identification, we present a method for autoregressive(AR) modelling of variious biomedical signal. Model order is estimated fly low rank approximation and coefficients are determined by innovation processes of Kalman filter derivation. An application of the method is given for visual evoked potentials.

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