• 대한전기학회:학술대회논문집
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• 대한전기학회 2011년도 제42회 하계학술대회
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• pp.1582-1583
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• 2011

Recently, it has been found that trifluoroiodomethane ( $CF_3I$) gas can replace $SF_6$ gas as a prospective substitute gas. For quantitative understanding of gas discharge phenomena, we should know electron collision cross sections and electron transport coefficients. Using electron collision cross sections of $CF_3I$ and Xe, we calculated elecron drift velocity, longitudinal coefficient, effective ionization coefficient in $CF_3I$-Xe mixtures using a two-term approximation of the Boltzmann equation. We also compared the electron transport coefficients in pure gas and those of 10%, 20%, 50%, and 70% $CF_3I$-Xe mixture gases. The present data may be showed appropriate ratios of $CF_3I$-Xe mixture gas for replacing the $SF_6$ gas.

• 전기학회논문지P
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• 제54권1호
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• pp.29-33
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• 2005

Energy distribution function for electrons in $SF_6$-Ar mixtures gas by MCS-BEq algorithm has been analysed over the E/N range $30{\sim}300$[Td] by a two term Boltana equation and by a Monte Carlo Simulation using a set of electron cross sections determined by other, authors, experimentally the electron swarm parameters for 0.2[%} and 0.5[%] $SF_6$-Ar mixtures were measured by time-of-flight(TOF) method. The result show that the deduced electron drift velocities, the electron ionization or attachment coefficients, longitudinal and transverse diffusion coefficients and mean energy agree reasonably well with theoretical for a rang of E/N values. The results obtained from Booltemann equation method and Monte Carlo simulation have been compared with present and previously obtained data and respective set of electron collision cross sections of the molecules.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2002년도 하계학술대회 논문집 Vol.3 No.2
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• pp.878-881
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• 2002

Energy distribution function for electrons in $SF_6+Ar$ mixtures gas used by MCS-BEq algorithm has been analysed over the E/N range 30 ~ 300[Td] by a two term Boltzmann equation and by a Monte Carlo Simulation using a set of electron cross sections determined by other authors, experimentally the electron swarm parameters for 0.2[%] and 0.5[%] $SF_6+Ar$ mixtures were measured by time-of-flight(TOF) method, The results show that the deduced electron drift velocities, the electron ionization or attachment coefficients, longitudinal and transverse diffusion coefficients and mean energy agree reasonably well with theoretical for a rang of E/N values. The results obtained from Boltzmann equation method and Monte Carlo simulation have been compared with present and previously obtained data and respective set of electron collision cross sections of the molecules.

• 전기학회논문지P
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• 제63권1호
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• pp.19-23
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• 2014

This paper describes the electron transport characteristics in $SF_6$-He gas calculated E/N values 0.1~700[Td] by the Monte Carlo simulation and Boltzmann equation method using a set of electron collision cross sections determined by the authors and the values of electron swarm parameters obtained by TOF method. This study gained the values of the electron swarm parameters such as the electron drift velocity, the electron ionization or attachment coefficients, longitudinal and transverse diffusion coefficients for $SF_6$-He gas at a range of E/N. A set of electron collision cross section has been assembled and used in Monte Carlo simulation to predict values of swarm parameters. The result of Boltzmann equation and Monte Carlo Simulation has been compared with experimental data by Ohmori, Lucas and Carter. The swarm parameter from the swarm study are expected to sever as a critical test of current theories of low energy scattering by atoms and molecules.

• E2M - 전기 전자와 첨단 소재
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• 제9권7호
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• pp.660-667
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• 1996

The electron transport characteristics in $SF_6$ gas is calculated for range of E/N values from 150 -800(Td) by the Monte Carlo simulation using a set of electron collision cross sections determined by the authors. The results suggest that the value of an electron swarm parameter such as the electron drift velocity, the electron ionization or attachment coefficients, longitudinal and transverse diffusion coefficients in nearly agreement with the respective experimental and theoretical for a range of E/N. The electron energy distributions function were analysed in sulphur hexaflouride at E/N:500 and 800(Td) for a case of the equilibrium region in the mean electron energy. The validity of the results obtained has been confirmed by a Time of Flight method also investigated as a set of electron collision cross section for sulphur Hexaflouride.

• 한국전기전자재료학회논문지
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• 제12권1호
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• pp.88-93
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• 1999

This paper describes the electron transport characteristics in $SiH_4$ gas calculated for the range of E/n:0.5~300(Td) and Pressure:0.5, 1, 2.5(Torr) by the Monte carlo simulation and Boltzmann equation method using a set of electron collision cross sections determined by the reported results. The motion has been calculated to give swarm parameters for the electron drift velocity, longitudinal and transverse diffusion coefficients, the electron ionization coefficients, characteristics energy and the electron energy distribution function. The electron energy distributions function has been analysed in $SiH_4$ at E/N: 30, 50(Td)for a case of the equilibrium region in the mean electron energy and respective set of electron collision cross sections. The results of Monte carlo simulation and Boltzmann equation have been compared with experimental data by ohmori ad Pollock.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2005년도 하계학술대회 논문집 Vol.6
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• pp.578-580
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• 2005

Energy distribution function for electrons in SF6-Ar mixtures gas used by MCS-BEq algorithm has been analysed over the E/N range 30~300[Td] by a two term Boltzmann equation and by a Monte Carlo Simulation using a set of electron cross sections determined by other authors, experimentally the electron swarm parameters for 0.2[%] and 0.5[%] $SF_6$-Ar mixtures were measured by TOF method, The results show that the deduced electron drift velocities, the electron ionization or attachment coefficients, longitudinal and transverse diffusion coefficients and mean energy agree reasonably well with theoretical for a rang of E/N values. The results obtained from Boltzmann equation method and Monte Carlo simulation have been compared with present and previously obtained data and respective set of electron collision cross sections of the molecules.

• Bulletin of the Korean Chemical Society
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• 제17권11호
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• pp.1065-1073
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• 1996

The dissociative recombination of O2+(v+)＋e-→O(1S)＋O(1D) has been theoretically investigated using the multichannel quantum defect theory (MQDT). Cross sections and rate coefficients at various electron energies are calculated. The resonant structures in cross section profile, which are hardly measurable in experiments, are also determined and the existence of Rydberg states is found to affect the rates. The theoretical rate coefficients are computed to be smaller than experimental ones. The reasons for this difference are explained. The two-step MQDT procedure is found to be very useful and promising in calculating the state-to-state rates of the dissociative recombination reaction which is a very important and frequently found phenomenon in Earth's ionosphere.

• 한국수자원학회논문집
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• 제41권1호
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• pp.1-15
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• 2008

본 연구의 목적은 금강수계의 가장 효율적인 가중치를 찾을 수 있는 절차를 제시하는 것이다. 일반적으로 다목적 최적화 모형의 결과는 목적함수에 부여된 가중치에 크게 좌우되는 경향이 있다. 특히 다목적 저수지 운영 문제의 경우는 어떤 유입량 시나리오가 적용되느냐에 따라 그에 적합한 가중치가 크게 달라질 수 있다. 따라서 유입량의 변동성을 감안해서 저수지 운영자에게 적합한 초기 가중치를 적용하는 것은 매우 큰 의미가 있다. 이에 본 연구는 유입량의 불확실성을 감안하여 적절한 가중치군을 도출할 수 있는 절차를 제안한다. 제안한 절차에서는 다중목적 최적화모형(GA-CoMOM)을 통해 파레토 집합에 대응되는 가중치군을 도출하고, DEA-윈도우분석(DEA-window analysis)과 교차효율성 분석(cross-efficiency analysis)을 사용하여 후보 가중치에 대한 순위를 산정하고, 이 결과를 분석해서 적합한 가중치를 선정한다. 이 절차를 금강 수계 저수지군 연계 운영 문제에 적용한 결과 유입량의 불확실성을 감안해서 가중치를 설정할 수 있었다.

• 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.