• Title/Summary/Keyword: Source Distribution

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Studies about Visible Light Distribution in PDP Cells with 3-dimesional Optical Code

  • Eom, Chul-Whan;Kang, Jung-Won
    • 한국정보디스플레이학회:학술대회논문집
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    • 2007.08a
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    • pp.582-584
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    • 2007
  • In order to improve the accuracy of simulated results, new UV source was designed. Previously the optical simulation was performed with the symmetric planar UV source. To design new UV source, UV distribution from the plasma fluid code was implanted to the 3-dimensional optical code to generate the visible light distribution. The results from planar UV source and new UV source were compared with the ICCD (Intensified CCD) image in real PDP cell and analyzed the variation of geometries and optical properties.

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Improvement of the Accuracy of Optical Simulation Using by the Multi-cube UV Source in PDP Cells (Multi-cube UV source 이용한 PDP에서 광학시뮬레이션의 정확성 개선에 관한 연구)

  • Kang, Jung-Won;Eom, Chul-Whan
    • Journal of the Semiconductor & Display Technology
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    • v.6 no.2 s.19
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    • pp.41-44
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    • 2007
  • Optical simulation of the rear and front panel geometries were needed to improve the luminance and efficiency in PDP cells. The 3-dimensional optical code can be used to analyze the variation of geometries and changing of optical properties. In order to improve the accuracy of simulated results, a new UV source, called a multi-cubes UV source, was designed. To design the source, at first UV distribution was calculated with the plasma fluid code and then the UV distribution was transformed to the multi-cube structures in the optical code. Compared to the results from existing UV source, called a planar UV source, could be improved the accuracy of visible light distribution. Simulated results were also compared to the visible distribution measured with the ICCD in a real PDP cell.

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A Study on Free Surface Effect of 2-D Airfoils (2차원 익형의 자유수면 효과에 관한 연구)

  • Park, Il-Ryong;Jeon, Ho-Hwan
    • Journal of Ocean Engineering and Technology
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    • v.9 no.2
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    • pp.75-82
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    • 1995
  • The free surface effects on the aerodynamic performance of 2-D wings are investigated based on the potential flow approximation. The wing is represented b source and vortex distributions on the wing surface. The steady free surface effect is taken into account by source distribution on the free surface and the velocity potentials of air and water flows are obtained. Using three different techniques, namely, positive image method, inverse image method and source distribution method, numerical results are obtained for wave elevation, pressure distribution and lift coefficient with various foil sections. The wave elevation calculated by the inverse image method is shown to be very small even at higher speeds so that the free surface effect on the performance of wings is regraded negligible. However, the wave elevations by the positive image method and source distribution method are relatively high at higher speeds and accordingly the free surface effects on wings can not be neglected.

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Analysis of Heat Source Distribution in Low Voltage Condenser (저압 콘덴서의 열원 분포 해석)

  • Kim, Jong-Gyeum;Lee, Dong-Ju;Kim, Il-Jung;Park, Young-Jeen
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.59 no.7
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    • pp.1242-1247
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    • 2010
  • In this study, the heat source distributions at the end side and the center of the electrode are analyzed to estimate the electrical stress due to the harmonics from the nonlinear loads. The governing equation at the analysis area of low voltage condenser are numerically solved using the finite element software package to analyze the effects of heat source distribution due to the 5th and 7th harmonics, which can exist normally in the distribution network and can be applied to the low voltage condenser. Finally, the heat source distribution from the harmonics is compared and analyzed with the heat source distribution from the fundamental component of the applied voltage.

A Fault Location Algorithm Using Adaptively Estimated Local Source Impedance for a Double-Circuit Transmission Line System (자기단 전원 임피던스 추정 기법을 사용한 병행 2회선 송전선로 고장점 표정 알고리즘)

  • Park, Gun-Ho;Kang, Sang-Hee;Kim, Sok-Il;Shin, Jonathan H.
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.61 no.3
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    • pp.373-379
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    • 2012
  • This paper presents a fault location algorithm based on the adaptively estimated value of the local sequence source impedance for faults on a parallel transmission line. This algorithm uses only the local voltage and current signals of a faulted circuit. The remote current signals and the zero-sequence current of the healthy adjacent circuit are calculated by using the current distribution factors together with the local terminal currents of the faulted circuit. The current distribution factors consist of local equivalent source impedance and the others such as fault distance, line impedance and remote equivalent source impedance. It means that the values of the current distribution factors can change according to the operation condition of a power system. Consequently, the accuracy of the fault location algorithm is affected by the two values of equivalent source impedances, one is local source impedance and the other is remote source impedance. Nevertheless, only the local equivalent impedance can be estimated in this paper. A series of test results using EMTP simulation data show the effectiveness of the proposed algorithm. The proposed algorithm is valid for a double-circuit transmission line system where the equivalent source impedance changes continuously.

A study of Heat Transfer by the Finite Element Method - Around Square Heat Source - (유한요소법에 의한 열전달 연구 -4각열원 주위-)

  • 장재은
    • Journal of the Korean Society of Safety
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    • v.13 no.1
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    • pp.26-33
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    • 1998
  • This paper subdivided the interior solid into triangular shape of equal size to calculate the temperature distribution around the square heat source of it, and compared calculated values with measured ones. The result obtained are as follows. 1) It was found that we can calculate the temperature distribution around the square heat source of interior solid by the variational method of the finite element method as the calculated values were almost accord with the measured ones. 2) The temperature distributed were higher when the distances between heat source were farther and lower when those nearer. 3) Vertical surface temperature distribution is remarkably efficient by thermal conductivities.

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A Study on the Rectangular Distribution of far Field Sources in Equivalent Source Method (등가음원법에서의 직육면체형 원거리음원 배치에 관한 연구)

  • 백광현
    • The Journal of the Acoustical Society of Korea
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    • v.23 no.1
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    • pp.40-46
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    • 2004
  • The equivalent source method (ESM) uses two groups of equivalent source positions. One group includes the first order images of the sound source inside the enclosure. The positions of the other group are usually on a spherical surface some distance outside the enclosure. A proper selection of the positions for the far field sources could greatly improve the performance of the modeling accuracy and reduce the number of the sources to achieve the required accuracy. This study uses optimally distributed far field source positions on the surface of enlarged version of the rectangular enclosure instead of using typical spherical distribution. Simulations using various sizes of the box shaped distribution are executed and optimal positions are searched using an optimization technique from the larger number of candidate positions. The results of using these far field source positions are compared and analyzed.

Prediction of A Rise in Temperature Distribution of Mold Transformer for Power Distribution System (배전용 몰드변압기에 대한 상승 온도 분포 예측)

  • Lee, Jeong-Keun;Kim, Ji-Ho;Lee, Hyang-Beom
    • 한국정보통신설비학회:학술대회논문집
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    • 2009.08a
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    • pp.391-394
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    • 2009
  • In this paper, achieved rise temperature distribution about degradation phenomenon of 2 MVA distribution mold transformer using finite element method (FEM). Usually, life of transformer is depended on temperature distribution of specification region than thermal special quality of transformer interior. Specially, life of transformer by decline of dielectric strength decreases rapidly in case rise by strangeness transformer interior hot spot temperature value permits. Because calculating high-voltage winding and low-voltage winding of mold transformer and Joule's loss of core for improvement these life, forecasted heat source, and high-voltage winding and low-voltage winding of mold transformer and rise temperature distribution of core for supply of electric power and temperature distribution of highest point on the basis of the result Also, calculated temperature rise limit of mold transformer and permission maximum temperature using analysis by electron miracle heat source alculate and forecasted rise temperature distribution by heat source of thermal analysis with calculated result.

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Dose Distribution of $^{60}$ Co Source as Brachytherapy in Tissue (근접조사 치료에 사용되는 $^{60}$ Co source의 조직내에서 선량분포)

  • 유명진
    • Progress in Medical Physics
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    • v.1 no.1
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    • pp.85-90
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    • 1990
  • Berger formulation was used to calculate the dose distribution of $^{60}$ Co source in tissue. $^{60}$ Co source was supposed as point source. The effect of the stainless-steel around the source was considered and Taylor Approximation Method was used for calculating exposure build-up factor. Calculated depth dose data was compared with measured data which was measured by the ionization chamber.

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Characterization of the 2.5 MeV ELV electron accelerator electron source angular distribution using 3-D dose measurement and Monte Carlo simulations

  • Chang M. Kang;Seung-Tae Jung;Seong-Hwan Pyo;Youjung Seo;Won-Gu Kang;Jin-Kyu Kim;Young-Chang Nho;Jong-Seok Park;Jae-Hak Choi
    • Nuclear Engineering and Technology
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    • v.55 no.12
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    • pp.4678-4684
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    • 2023
  • Using the Monte Carlo method, the impact of the angular distribution of the electron source on the dose distribution for the 2.5 MeV ELV electron accelerator was explored. The experiment measured the 3-D dose distribution in the irradiation chamber for electron energies of 1.0 MeV and 2.5 MeV. The simulation used the MCNP6.2 code to evaluate three angular distribution models of the source: a mono-directional beam, a cone shape, and a triangular shape. Of the three models, the triangular shape with angles θ = 30°, φ = 0° best represents the angle of the scan hood through which the electron beam exits. The MCNP6.2 simulation results demonstrated that the triangular model is the most accurate representation of the angular distribution of the electron source for the 2.5 MeV ELV electron accelerator.