• Title/Summary/Keyword: Multi-term

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The study of electron drift velocity in $CF_4+Ar$ molecular gas mixture by 2-term and multi-term approximation of the Boltzmann equation (다항근사 및 2항근사 볼츠만 방정식을 이용한 $CF_4+Ar$ 혼합기체의 전자이동속도 연구)

  • Song, Byoung-Doo;Ha, Sung-Chul;Jeon, Byoung-Hoon
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2004.07b
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    • pp.1179-1182
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    • 2004
  • This paper describes the information for quantitative simulation of weakly ionized plasma. In previous paper, we calculated the electron transport coefficients in $CF_4+Ar$ gas mixture by using two-term approximation of Boltzmann equation. but there is difference between the result of the two-term and the multi-term approximation of the Boltzmann equation in $CF_4$ gas. Therefore, in this paper, we calculated the electron drift velocity (W) in $CF_4+Ar$ gas mixture for range of E/N values from $0.01\sim500[Td}$ at the temperature was 300[K] and pressure was 1[Torr] by multi-term approximation of the Boltzmann equation by Robson and Ness. The results of two-term and multi-term approximation of the Boltzmann equation has been compared with each other for a range of E/N.

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24 hour Load Forecasting using Combined Very-short-term and Short-term Multi-Variable Time-Series Model (초단기 및 단기 다변수 시계열 결합모델을 이용한 24시간 부하예측)

  • Lee, WonJun;Lee, Munsu;Kang, Byung-O;Jung, Jaesung
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.66 no.3
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    • pp.493-499
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    • 2017
  • This paper proposes a combined very-short-term and short-term multi-variate time-series model for 24 hour load forecasting. First, the best model for very-short-term and short-term load forecasting is selected by considering the least error value, and then they are combined by the optimal forecasting time. The actual load data of industry complex is used to show the effectiveness of the proposed model. As a result the load forecasting accuracy of the combined model has increased more than a single model for 24 hour load forecasting.

The comparison of electron transport coefficients of gases for analysis of multi-term approximation of the Boltzmann equation (다항근사 볼츠만 방정식의 타당성 검토를 위한 가스의 전자수송계수 비교)

  • Song, Byoung-Doo;Ha, Sung-Chul;Jeon, Byoung-Hoon
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2003.05e
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    • pp.69-72
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    • 2003
  • This paper describes the information for the difference between two-term and multi-term approximation of the Boltzmann. In previous paper, we calculated the electron transport coefficients in pure Oxygen and Argon gases by using two-term approximation of Boltzmann equation. Therefore, in this paper, we calculated the electron transport coefficients(W and $N{\cdot}D_L$) in pure Oxygen and Argon gases for range of E/N values from 0.01~500[Td] at the temperature was 300[K] and pressure was 1[Torr] by using multi-term approximation of the Boltzmann equation by Robson and Ness, The results of two-term and multi-term approximation of the Boltzmann equation has been compared with the experimental data for a range of E/N.

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An Application of Two-term and Multi-term Approximation of Boltzmann Equation to Electron Swarm Method (전자군 방법에 이용되는 2항근사와 다항근사 볼츠만 방정식의 적용)

  • 하성철;전병훈
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.15 no.1
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    • pp.79-84
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    • 2002
  • An accurate cross sections set is necessary for the quantitatively understanding and modeling of plasma phenomena. By using the electron swarm method, we determine an accurate electron cross sections set for objective atoms or molecule at low electron energy range. It is general calculation that used in this method to an two-term approximation of Boltzmann equation. But it may give erroneous transport coefficients for CF$_4$ molecule treated in this paper having \`C2v symmetry\`, therefore, multi-term approximation of the Boltzmann equation analysis which can consider anisotropic scattering exactly is carried out. It is necessary to require understanding of the fundamental principle of analysis method. Therefore, in this paper, we compared the electron transport coefficients(W and ND$\_$L/) in pure Ar, O$_2$, and CF$_4$ gas calculated by using two-term approximation of the Boltzmann equation analysis code uses the algorithm proposed by Tagashira et al. with those by multi-term approximation by Rubson and Ness which was developed at James-Cook university, and discussed an application and/or validity of the calculation method by comparing these calculated results.

Design and Application of Term Project Model for Game Mathematics in Flipped Learning Environments (플립드러닝 환경에서 게임수학 텀프로젝트 모형 설계 및 적용)

  • Choi, Youngmee
    • Journal of Korea Multimedia Society
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    • v.20 no.7
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    • pp.1102-1112
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    • 2017
  • The purpose of this study is to design and application of term project model for Game Math in flipped learning environment. In the term project self study model, students interacts with multi-instruction materials and multi-tutors on flipped learning. We develop a case for game update term project and implement it to a real Game Math classroom. As a result, we show the positive learning experiences focused on effects of technology and human relation through survey.

A study on a multi-input time control of multi-joint manipulator using sliding mode (슬라이딩 모드를 이용한 다관절 매니퓰레이터의 다입력 실시간 제어에 관한 연구)

  • 이민철
    • 제어로봇시스템학회:학술대회논문집
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    • 1992.10a
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    • pp.652-657
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    • 1992
  • This paper presents to accomplish successfully a multi-input real time control by applying control hierarchy for sliding mode of multi-joint manipulators whose nonlinear terms are regarded as disturbances. We- could simplify the dynamic equations of a manipulator and servo system, which are composed of linear elements and nonlinear elements, by assuming that nonlinear terms, which are Inertia term, gravity force term, Coriolis force term and centrifugal force term, are external disturbance. By simplifying that equation, we could easily obtain a control input which satisfy sliding mode of multi-input system. We proposed a new control input algorithm in order to decrease chattering by changing control input according as effect of disturbance if a control response become within allowance error range. In this experiments, we used DSP(Digital Signal Processor) controller to suppress chattering by time delay of calculation and to carry out real time control.

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The analysis of electron transport coefficients in Xenon gas by multi-term approximation of the Boltzmann equation (볼츠만 다항근사 방정식을 이용한 Xe 가스의 전자수송계수 해석)

  • Jeon, Byoung-Hoon;Ha, Sung-Chul;Song, Byoung-Doo
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2003.05e
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    • pp.73-76
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    • 2003
  • This paper describes the information for quantitative simulation of weakly ionized plasma. In previous paper, we calculated the electron transport coefficients in pure Xenon gas by using two-term approximation of Boltzmann equation. Therefore, in this paper, we calculated the electron transport coefficients(W, $N{\cdot}D_L$ and $D_{L/{\mu}}$) in pure Xenon gas for range of E/N values from 0.01 ~ 500[Td] at the temperature was 300[K] and pressure was 1[Torr] by using multi-term approximation of the Boltzmann equation by Robson and Ness, The results of two-term and multi-term approximation of the Boltzmann equation has been compared with the experimental data by L. S. Frost and A. V. Phelps for a range of E/N.

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The analysis of electron transport coefficients in $CF_4$ molecular gas by multi-term approximation of the Boltzmann equation (다항근사 볼츠만 방정식에 의한 $CF_4$ 분자가스의 전자수송계수 해석)

  • Jeon, Byung-Hoon;Park, Jae-June;Ha, Sung-Chul
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2001.11b
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    • pp.141-144
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    • 2001
  • An accurate cross sections set are necessary for the quantitatively understanding and modeling of plasma phenomena. By using the electron swarm method. we determine an accurate electron cross sections set for objective atoms or molecule at low electron energy range. In previous paper, we calculated the electron transport coefficients in pure $CF_4$ molecular gas by using two-term approximation of the Boltzmann equation. And by using this simulation method. we confirmed erroneous calculated results of transport coefficients for $CF_{4}$ molecule treated in this paper having 'C2v symmetry' as $C_{3}H_{8}$ and $C_{3}F_{8}$ which have large vibrational excitation cross sections which may exceed elastic momentum transfer cross section. Therefore, in this paper, we calculated the electron transport coefficients(W and $ND_L$) in pure $CF_4$ gas by using multi-term approximation of the Boltzmann equation by Robson and Ness which was developed at lames-Cook university, and discussed an application and/or validity of the calculation method by comparing the calculated results by two-term and multi-term approximation code.

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The analysis of electron transport coefficients in CF$_4$ molecular gas by multi-term approximation of the Boltzmann equation (다항근사 볼츠만 방정식에 의한 CF$_4$분자가스의 전자수송계수 해석)

  • 전병훈;박재준;하성철
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2001.11a
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    • pp.141-144
    • /
    • 2001
  • An accurate cross sections set are necessary for the quantitatively understanding and modeling of plasma phenomena. By using the electron swarm method, we determine an accurate electron cross sections set for objective atoms or molecule at low electron energy range. In previous paper, we calculated the electron transport coefficients in pure CF$_4$ molecular gas by using two-term approximation of the Boltzmann equation. And by using this simulation method, we confirmed erroneous calculated results of transport coefficients for CF$_4$ molecule treated in this paper having 'C2v symmetry'as C$_3$H$_{8}$ and C$_3$F$_{8}$ which have large vibrational excitation cross sections which may exceed elastic momentum transfer cross section. Therefore, in this paper, we calculated the electron transport coefficients(W and ND$_{L}$) in pure CF$_4$ gas by using multi-term approximation of the Boltzmann equation by Robson and Ness which was developed at James-Cook university, and discussed an application and/or validity of the calculation method by comparing the calculated results by two-term and multi-term approximation code.e.

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Language performance analysis based on multi-dimensional verbal short-term memories in patients with conduction aphasia (다차원 구어 단기기억에 따른 전도 실어증 환자의 언어수행력 분석)

  • Ha, Ji-Wan;Hwang, Yu Mi;Pyun, Sung-Bom
    • Korean Journal of Cognitive Science
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    • v.23 no.4
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    • pp.425-455
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    • 2012
  • Multi-dimensional verbal short-term memory mechanisms are largely divided into the phonological channel and the lexical-semantic channel. The former is called phonological short-term memory and the latter is called semantic short-term memory. Phonological short-term memory is further segmented into the phonological input buffer and the phonological output buffer. In this study, the language performance of each of three patients with similar levels of conduction aphasia was analyzed in terms of multi-dimensional verbal short-term memory. To this end, three patients with conduction aphasia were instructed to perform four different aspects of language tasks that are spontaneous speaking, repetition, spontaneous writing, and dictation in both word and sentence level. Moreover, the patients' phonological memories and semantic short-term memories were evaluated using digit span tests and verbal learning tests. As a result, the three subjects exhibited various types of performances and error responses in the four aspects of language tests, and the short-term memory tests also did not produce identical results. The language performance of three patients with conduction aphasia can be explained according to whether the defects occurred in the semantic short-term memory, phonological input buffer and/or phonological output buffer. In this study, the relations between language and multi-dimensional verbal short-term memory were discussed based on the results of language tests and short-term memory tests in patients with conduction aphasia.

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