• Title/Summary/Keyword: 스페이서

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A Study for Stray Light Distribution of Mobile Phone Camera Consisting of Two Aspheric Lenses (2매 비구면 렌즈로 구성된 폰 카메라에서 미광 분포에 대한 연구)

  • Park, Kwang-Woo;Lee, Jong-Ung
    • Korean Journal of Optics and Photonics
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    • v.20 no.1
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    • pp.6-15
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    • 2009
  • A mobile phone camera consisting of two aspheric lenses is designed, and stray light distribution on the image plane is analyzed. We assume that most of the incident light is absorbed on the inner surfaces of the lens barrel and spacers, only a small fraction of the light is scattered uniformly. Assuming that 10% of the incident light is scattered on the barrel and spacers, the maximum value of stray light is 7.1% of the ideal image intensity. The result of analysis shows that stray light originated mostly from internal reflection on the ribs. The contributions of scattering by the barrel and spacers are relatively small. To reduce the internal reflection, thin absorbing plates are inserted between lenses, and the shapes of spacers are modified. After the redesigning of the lens barrel, the maximum value of stray light is reduced to 1.1% of the ideal image intensity.

An Investigation on DC Electric Field Distribution according to the Material and Configureation of Epoxy Spacer for HVDC GIS (HVDC GIS용 에폭시 스페이서의 재질과 형상에 따른 전계분포 특성 연구)

  • Koo, Jae-Hong;Hwang, Jae-Sang;Kwon, Ik-Soo;Shin, Woo-Ju;Koo, Ja-Yoon;Lee, Bang-Wook
    • Proceedings of the KIEE Conference
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    • 2015.07a
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    • pp.1185-1186
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    • 2015
  • 본 논문에서 HVDC $SF_6$ 가스절연시스템(GIS)에서 최적의 에폭시 재질을 알아내기 위해 $Al_2O_3$$SiO_2$ 나노필러가 첨가된 총 다섯 종류의 에폭시에 대한 도전율을 측정하여 DC 전계분포 해석을 수행하였다. 해석결과 $75^{\circ}$의 접촉각(에폭시 스페이서와 도체가 이루는 각도)가 가장 우수한 전계특성을 나타냈고 $Al_2O_3$ 2 hundred per resin(phr)의 나노필러가 첨가된 에폭시가 가장 우수한 절연매질로써의 특성을 보여주었다. 또한, 삼중점에서 전계집중 완화를 위하여 $Al_2O_3$ 2 phr의 나노필러가 첨가된 에폭시의 데이터를 기반으로 열해석을 고려한 정상상태 및 극성 반전에 대해 DC 전계 해석을 수행하여 최적의 에폭시 스페이서 형상을 도출하였다.

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Development of the Bone Type Concrete Spacer with Crack Resistance for Construction (시공균열저항성을 갖는 본타입 콘크리트 스페이서 개발)

  • Lee, Min-Jae;Kim, Ji-Ho;Sung, Jong-Hyun;Choi, Duck-Jin;Kim, Jin-Man
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2012.11a
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    • pp.35-38
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    • 2012
  • Spacers which we have studied is the secondary product of the concrete to apply on concrete structure. It is needed to secure equal or greater performance than structural concrete that it is applied. There is a tendency that concrete structures are strengthened more and more. Therefore, designed set up position of reinforcement is used more and more, so it is needed increasingly high strength spacer. We have been doing a series of research to develop the different typed high strength spacer having crack resistance during constructing. The bearing load of different type spacer shows approximately 35% lower load than those in the general spacers.

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Development of High-Strength Concrete Spacer with Crack Resistance during Construction (시공시 균열저항성을 갖는 고강도 콘크리트 스페이서 개발)

  • Lee, Min-Jae;Choi, Ji-Ho;Choi, Duck-Jin;Cho, Young-Hwi;Kim, Jin-Man
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2012.05a
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    • pp.5-8
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    • 2012
  • Spacers which we studied about is the secondary product of the concrete and it is applied on concrete structure. Therefore, securing equal or greater performance than concrete is desirable. Also, there is a tendency that concrete structures are strengthened. Therefore, reinforcement is used more and it is needed highly strengthened spacer. In this study, therefore, we would like to develop highly strengthened spacer which has crack resistance during construction. After this study, we confirmed that the spacer we developed has good crack resistance in construction.

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Design of the Spacers Arrangement for Field Emission Displays using Topology Optimization Technique (위상 최적화 기법을 잉요한 FED용 스페이서의 배치 설계)

  • Chung, Tae-Eun
    • Journal of the Korean Society for Precision Engineering
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    • v.17 no.11
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    • pp.49-54
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    • 2000
  • A field emission display has spacers separating the emitting base and display face. The arrangement of the spacer is important for maintenance of required clearance, endurance of bending stresses, and efficient vacuum sealing. Topology optimization technique with material density was introduced to select the best position of the spacers from the available positions. The displacement and Von Mises stress distribution of the panels with optimal spacers were calculated by finite element method. Also the design guide for adding eliminating spacers was proposed.

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