• Title/Summary/Keyword: AR approximation

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

  • Kim, Sang-Nam
    • The Transactions of the Korean Institute of Electrical Engineers P
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    • v.52 no.1
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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.

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

  • Kim, Sang-Nam
    • The Transactions of the Korean Institute of Electrical Engineers P
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    • v.60 no.3
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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.

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

  • 하성철;전병훈
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.14 no.2
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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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Analysis of electron transport properties of $CF_4+Ar$ mixtures gas by the TOF method (TOF법에 의한 $CF_4+Ar$ 혼합기체의 전자수송특성 해석)

  • 서상현;하성철;유회영
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 1998.06a
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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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Electron Mean Energy in CF4, CH4, Ar mixtures (CF4, CH4, Ar 혼합기체의 전자 평균에너지)

  • Kim, Sang-Nam
    • The Transactions of the Korean Institute of Electrical Engineers P
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    • v.64 no.4
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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.

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

  • 김덕영;박종환;김성환
    • Journal of Biomedical Engineering Research
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    • v.20 no.3
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    • pp.307-314
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    • 1999
  • This paper describes an informatlon compression of electrically evoked myoelectric signal, M-wave. This wave shows a direct response m lato-response of nerve conductlQn study and has a characteristic with finite time support. M-wave is a useful factor for investing neurodi~ease and is often desirable to have a compact description of its shape and time evolution. The aim of this paper is to show that the AR modeling IS a effective method for compressing an information of M-wave. First, AR model parameters of real M-wave are estimated. And then. they are verified by approximatmg a M-wave using estimated AR parameters and by comparing to other melhod, Hermite tlansform[4]. To concretely evaluate the proposed method, the NMSE(normalized mean square error) of approximation curves are compared. As a result, AR modeling is effective for M-wave assessment because of its capability for the information compression.

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

  • Kim, Sang-Nam
    • The Transactions of the Korean Institute of Electrical Engineers P
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    • v.61 no.1
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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.

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

  • Kim, Sang-Nam
    • The Transactions of the Korean Institute of Electrical Engineers P
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    • v.55 no.2
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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.

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

  • 하성철;김상남;유회영;서상현;임상원;전병훈
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.11 no.1
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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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AR modelling for a biomedical signal using Kalman filter (Kalman filter를 이용한 생체신호의 AR modelling)

  • Kim, D.K.;Park, H.J.;Chee, Y.J.;Park, K.S.;Lee, C.W.
    • Proceedings of the KOSOMBE Conference
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    • v.1997 no.05
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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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