• Title/Summary/Keyword: energy transport

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Temperature Dependence of Energy Gap and Thermodynamic Function Properties of Undoped and Co-doped $Cd_{4}GeSe_{6}$ Sing1e Crystals by Chemical Transport Reaction Method (화학수송법으로 성장한 $Cd_4GeSe_{6}$$Cd_{4}GeSe_{6}$ : $CO^{2+}$ 단결정에서 에너지 띠 간격의 온도의존성 및 열역학함수 추정)

  • Kim, Nam-Oh;Kim, Hyung-Gon;Kim, Duck-Tae;Hyun, Seung-Cheol;Oh, Gum-Kon
    • The Transactions of the Korean Institute of Electrical Engineers C
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    • v.52 no.2
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    • pp.85-90
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    • 2003
  • In this work $Cd_{4}GeSe_{6}$ and $Cd_{4}GeSe_{6}$ : $Co^{2+}$ single crystals were grown by the chemical transport reaction method and the structure of $Cd_{4}GeSe_{6}$ and $Cd_{4}GeSe_{6}$ : $Co^{2+}$ single crystals were monoclinic structure. The temperature dependence of optical energy 9ap was fitted well to Varshni equation. Also, the entropy, enthalpy and heat capacity were deduced from the temperature dependence of optical energy gap.

Analysis of Electron Energy Distribution Function and Transport Characteristic in SiH$_4$ Gas Plasma by MCS-BE Method (MCS-BE법을 이용한 SiH$_4$가스 프라즈마중의 전자에너지분포함수와 수송특성해석)

  • 이형윤;하성철;유회영;김상남;임상원;문기석
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 1997.04a
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    • pp.154-159
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    • 1997
  • This paper describes the electron transport characteristic in SiH$_4$ gas calculated for range of E/N values from 0.5~300(Td) by the Monte Calro simulation and Boltzmann equation method using a set of electron collision cross sections determined by the authors and the values of electron swarm parameters are obtained for TOF method. The results gained that the value of an electron swarm parameter such as the electron drift velocity, the electron ionization coefficients longitudinal and transverse diffusion coefficients, characteristics energy agree with thee experimental and theoretical for a range of E/N. The electron energy distributions function were analysed in monosilane at EN : 30, 50(Td) for a case of equilibrium region in the mean electron energy. The validity of the results obtained has been confirmed by a TOF method.

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The Analysis of Electron Transport Characteristics in $SiH_4$ Plasma ($SiH_4$ 플라즈마중의 전자수송특성 해석)

  • Lee, Hyoung-Yoon;Ha, Sung-Chul;Kim, Dae-Yeon
    • Proceedings of the KIEE Conference
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    • 1998.11c
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    • pp.925-928
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    • 1998
  • In this paper, the electron transport characteristics in $SiH_4$ has been analysed over the E/N range $0.5{\sim}300[Td]$ and Pressure value 0.5, 1, 2.5 [Torr] by a two-term approximation Boltzmann equation method and by a Monte Carlo simulation. The motion has been calculated to give swarm parameters for the electron drift velocity. diffusion coefficient, electron ionization, mean energy and the electron energy distribution function. The electron energy distribution 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 Boltzmann equation and Monte carlo simulation have been compared with experimental data by Pollock, Ohmori, cottrell and Walker.

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Speech Recognition Using the Energy and VQ (에너지와 VQ를 이용한 음성 인식)

  • Hwang, Young-Soo
    • The Journal of The Korea Institute of Intelligent Transport Systems
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    • v.6 no.3
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    • pp.87-94
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    • 2007
  • In this paper, the performance of the speech recognition and speaker adaptation methods are studied. The speech recognition using energy state and VQ(Vector Quantization) is suggested and the speaker adaptation methods(Maximum a posteriori probability estimation, linear specrum estimation) are considered. The experimental results show that recognition ration using energy state is 2-3 % better than that of general VQ.

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Exciplex emission in bilayer Light-emitting device

  • Liang, Yu-Jun;Zhang, Hong-Jie;Han, Sang-Do;Jung, Young-Ho;Taxak, Vinod Bala
    • 한국정보디스플레이학회:학술대회논문집
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    • 2002.08a
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    • pp.762-765
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    • 2002
  • The bilayer organic light-emitting diode using Al (DBM) $_3$ (DBM=Dibenzoylmethane) as an emitting material and poly (N-vinylcarbazole) (PVK) as hole-transport material, emitted bright blue-green light instead of blue light. The blue-green emission is attributed to exciplex formation at the solid interface between Al (DBM) $_3$ and the hole-transport material. The exciplex formation was evidenced by the measurement of the photoluminescence spectra and lifetimes of Al (DBM) $_3$, PVK and an equimolar amount of mixture of Al (DBM) $_3$ and PVK.

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Power Management of Open Winding PM Synchronous Generator for Unbalanced Voltage Conditions

  • EL-Bardawil, Ashraf;Moussa, Mona Fouad
    • Journal of Power Electronics
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    • v.16 no.6
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    • pp.2192-2201
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    • 2016
  • Wind energy is currently the fastest-growing electricity source worldwide. The cost efficiency of wind generators must be high because these generators have to compete with other energy sources. In this paper, a system that utilizes an open-winding permanent-magnet synchronous generator is studied for wind-energy generation. The proposed system controls generated power through an auxiliary voltage source inverter. The VA rating of the auxiliary inverter is only a fraction of the system-rated power. An adjusted control system, which consists of two main parts, is implemented to control the generator power and the grid-side converter. This paper introduces a study on the effect of unbalanced voltages for the wind-generation system. The proposed system is designed and simulated using MATLAB/Simulink software. Theoretical and experimental results verify the validity of the proposed system to achieve the power management requirements for balanced and unbalanced voltage conditions of the grid.

Electron Transport Characteristics in $SiH_4$ by MCS-BEq (MCS-BEq에 의한 $SiH_4$ 전자수송특성(電子輸送特性))

  • Seong, Nak-Jin;Kim, Sang-Nam
    • Proceedings of the KIEE Conference
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    • 2005.10a
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    • pp.97-100
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    • 2005
  • This paper describes the electron transport characteristics in SiH4 has been analysed over the E/N range 0.5${\sim}$300[Td] and Pressure value 0.5, 1, 2.5 [Torr] by a two-term approximation Boltzmann equation method and by a Monte Carlo simulation. The motion has been calculated to give swarm parameters for the electron drift velocity, diffusion coefficient, electron ionization, mean energy and the electron energy distribution function. The electron energy distribution 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 Boltzmann equation and Monte carlo simulation have been compared with experimental data by Pollock, Ohmori, cottrell and Walker.

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Nuclides Transport Analysis and Dose Calculation Using Dynamic Model for Rice Ingestion Pathway (쌀 섭취경로에서 동적모델을 사용한 장반감기핵종의 거동해석 및 내부피폭 선량계산)

  • Lee, Chang-Woo;Choi, Yong-Ho;Hwang, Won-Tae;Lee, Jeong-Ho
    • Journal of Radiation Protection and Research
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    • v.17 no.2
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    • pp.15-23
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    • 1992
  • Transport behaviors of Cs-137 and Sr-90 were analyzed and ingestion doses were calculated using dynamic model for rice field-rice-man pathway. Cs-137 binding strongly to soil remain longer in rice field than Sr-90. Foliar deposition on rice plant during growing period is the main contamination mechanism.

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Temperature Dependence of Energy Gap and Thermodynamic Function Properties of Undoped and Co-doped $Cd_{4}GeSe_{6}$ Single Crystals by Chemical Transport Reaction Method (화학수송법으로 성장한 $Cd_{4}GeSe_{6}$$Cd_{4}GeSe_{6}:Co$ 단결정에서 Energy Gap의 온도의존성 및 열역학함수 추정)

  • Kim, D.T.;Kim, N.O.;Choi, Y.I.;Kim, B.C.;Kim, H.G.;Hyun, S.C.;Kim, B.I.;Song, C.I.
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2002.08a
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    • pp.31-36
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    • 2002
  • In this work $Cd_{4}GeSe_{6}$ and $Cd_{4}GeSe_{6}:Co^{2+}$ single crystals were grown by the chemical transport reaction method and the structure of $Cd_{4}GeSe_{6}$ and $Cd_{4}GeSe_{6}:Co$ single crystals were monoclinic structure. The temperature dependence of optical energy gap was fitted well to Varshni equation. Also, the entropy, enthalpy and heat capacity were deduced from the temperature dependence of optical energy gap.

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Experiments for the Characteristic Evaluation of Pollutant Transport in Tidal Influenced Region (조파역내 오염물 이동특성 평가 실험)

  • Park, Geon Hyeong;Kim, Ki Chul;Jung, Sung Hee;Suh, Kyung Suk
    • Journal of Radiation Industry
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    • v.4 no.4
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    • pp.391-395
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    • 2010
  • The characteristics for pollutant transport in tidal influenced area was investigated using tidal wave hydraulic scale model. Hydraulic scale model was composed of the tidal generator, attenuation area and channel. Also, wave height, current meter and conductivity meter were used with the measured instruments in hydraulic scale model. NaCl with a tracer was used to evaluate the advection phenomena under the different velocity profiles. The arrival time of the maximum concentration in the condition of the relatively fast velocity was measured about 30 seconds faster than ones in the conditions of low velocity. The measured concentrations of the tracer were shown in the detection points of the flow direction consecutively.