• 제목/요약/키워드: View Angle

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PCB 구조적 설계에 따른 LED Module의 열적 광학적 특성 (Optical, Thermal property by Applied PCB Structure design)

  • 이승민;이성진;최기승;이종찬;박대희
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2006년도 제37회 하계학술대회 논문집 B
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    • pp.1275-1276
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    • 2006
  • As developing the information society, Lighting Emitted diode(LED) which is light source for illumination of next generation is attracted public attention. LED have many problem as narrow light view angle, high price, drift phenomenon of color coordinate, high heating problem for lower power, lower weight and small size. So, many researches have continued in a illumination as LED module type. in this problem, heating problem is very important and difficult and that is caused in decreasing phenomenon of brightness and drift phenomenon of color coordinate. so the problem of heating is urgent question for illumination of LED. In this paper, structural design of PCB changed as two type for solving the heating problem. also the properties of heating is analysed and optical properties is measured with heating image camera and spectrometer according to change in this design.

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한국산 목본식물에 대한 계통분류학적 연구 - 차나무과의 목재비교해부 - (Systematic Studies on Some Korean Woody Plants - A comparative wood anatomy of Theaceae -)

  • 소웅영
    • Journal of Plant Biology
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    • 제29권4호
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    • pp.317-327
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    • 1986
  • Anatomical characters of the trunk woods of Theaceae, including six genera and seven species collected in Korea, were studied to elucidate the relationship among the genera of the family. Among three genera in Ternstoemieae, Eurya is the least specialized, and Cleyera is less specialized than Ternstroemia in respect to the specialization of the perforation plate and the ray. In Theoieae consisting of three genera, the most primitive one is Thea, and Camellia is more primitive than Stewartia in the trive, from the view of the bar arrangement in scalariform perforation plate and the angle of end wall to the vessel axis. The specialization of the perforation plate of vessel element suggests that Theoieae is more advanced group than Ternstroemieae.

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유동(流動) 수치해석(數値解析)을 이용한 응집·침전지 유입 분배수로 설계인자 연구 (A Fluid Flow Numerical Study on the Design Factor of Inlet Distribution Channel for Flocculation/Sedimentation Basin)

  • 윤장근;김정현;오정우;하은정
    • 상하수도학회지
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    • 제14권4호
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    • pp.337-342
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    • 2000
  • In water treatment plants, open channel is used to distribute incoming flow to parallel treatment unit, such as flocculation basin and sedimentation basin. These control devices must be designed so that the incoming flow evenly distributed to the process unit. this is important in the view of optimizing process unit. In the recent past. significant insights into the sedimentation process have been developed. In this study, the 2-D computer program is developed to investigate fluid flow field and velocity vectors in flocculation sedimentation inlet distribution weir and calculate flow rates in each inlet weir. The specific purpose of this study is to analyze physical design factors, such as now rates, shape of channel, tapered angle in tapered type channel and main channel width.

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다각도 다중시점 상에서의 비디오 마이닝을 통한 비정상행위 탐지기법 (Abnomalous Behavior Detection Technique Using Multi angle and Multi view Video Mining)

  • 신주한;김기호;오세인;이원석
    • 한국IT서비스학회:학술대회논문집
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    • 한국IT서비스학회 2009년도 추계학술대회
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    • pp.524-527
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    • 2009
  • 최근 감시, 상황판단, 정보전달에 있어서 비디오 영상의 사용이 점점 증가하고 있다. 그러나 비디오 영상에 나타나는 객체들의 비정상행위를 탐지하는 것은 사용자에게 의존한다. 따라서 사용자가 비정상 행위를 놓치기 쉽고, 상황에 대한 대처가 늦어진다는 문제가 발생한다. 이러한 점을 개선하기 위해 실시간 영상 마이닝 기법을 이용한 비정상행위 탐지법이 연구되었으나, 제약 조건이 심하고, 불필요하게 추적되는 데이터가 많아 효율이 떨어진다는 단점이 있다. 본 논문에서는 이러한 단점을 개선하여 3차원 환경에서의 객체의 추적에 대한 정확도를 높이고 일반적인 상황에서도 적용이 가능한 비디오 마이닝을 이용한 비정상 행위 탐지 기법을 제안한다.

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Tomographic Reconstruction of a Three-Dimensional Flow Field with Limited Interferometric Data

  • Cha, Dong-Jin
    • International Journal of Air-Conditioning and Refrigeration
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    • 제8권2호
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    • pp.11-22
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    • 2000
  • Holographic interferometric tomography can provide reconstruction of instantaneous three-dimensional gross flow fields. The technique however confronts ill-posed reconstruction problems in practical applications. Experimental data are usually limited in projection and angular scanning when a field is captured instantaneously or under the obstruction of test models and test section enclosures. An algorithm, based on a series expansion method, has been developed to improve the reconstruction under the ill-posed conditions. A three-dimensional natural convection flow around two interacting isothermal cubes is experimentally investigated. The flow can provide a challenging reconstruction problem and lend itself to accurate numerical solution for comparison. The refractive index fields at two horizontal sections of the thermal plume with and without an opaque object are reconstructed at a limited view angle of 80$\circ$. The experimental reconstructions are then compared with those from numerical calculation and thermocouple thermometry. It confirms that the technique is applicable to reconstruction of reasonably complex, three-dimensional flow fields.

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Second-order Motion Characteristics of a Semi-submersible Platform in Waves

  • Hong, Sa-Young;Nam, Bo-Woo;Kim, Jin-Ha;Kim, Young-Shik;Hong, Seok-Won;Kim, Young-Soo
    • International Journal of Ocean System Engineering
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    • 제1권3호
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    • pp.155-164
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    • 2011
  • The second-order motion characteristics of a semi-submersible are investigated in regular waves. A higher-order boundary element method in a frequency domain and a finite element method in a time-domain were applied to the numerical analysis of the nonlinear hydrodynamic force and motion characteristics of semi-submersibles in view point of potential flow. Various aspects of nonlinear effects on the heave and roll of a semi-submersible were numerically investigated and some selected cases were compared with the model test data.

락볼트로 보강된 심형기초의 하중-침하 분석 (Load-Settlement Characteristics of Drilled Shafts Reinforced by Rockbolts)

  • 윤경식;이대수;정상섬
    • 한국지반공학회:학술대회논문집
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    • 한국지반공학회 2002년도 가을 학술발표회 논문집
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    • pp.366-373
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    • 2002
  • This paper describes the load distribution and settlement of rockbolted-drilled shafts subjected to axial and lateral loads with the view to shortening the embedded depth of the pile shaft. The emphasis was on quantifying the reinforcing effects of rockbolts placed from the shafts to surrounding weathered rocks based on small-scale model tests peformed on instrumented piles. The major influencing parameters on reinforcing drilled shaft behavior are the number, the positions on the shaft, the grade, and the inclination angle at which the rockbolts are placed. The model tests was 1/40 scaled simulations of the behavior of the drilled shafts with varying combinations of the major influencing parameters. The incremental effects of reinforcement based on the various parameters have been weighed against load transfer characteristics before and after rockbolt installations.

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Dual-Mode Liquid Crystal Devices with Switchable Memory and Dynamic Modes

  • Yao, I-An;Chen, Chueh-Ju;Yang, Chiu-Lien;Pang, Jia-Pang;Liao, Shih-Fu;Li, Jia-Hsin;Wu, Jin-Jie
    • 한국정보디스플레이학회:학술대회논문집
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    • 한국정보디스플레이학회 2009년도 9th International Meeting on Information Display
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    • pp.600-603
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    • 2009
  • The liquid crystal device with switchable dynamic mode and memory mode has been investigated and developed. The proposed device reveals splay, ${\pi}$ twist and bend states by selective switching among them. In the dynamic mode, this device is operated in the bend state which exhibits the wide view angle and fast response time properties due to the self-compensated bend structure and flow accelerated fast response time. In the memory mode, the permanent memory characteristics in the splay and ${\pi}$ twist sates are obtained, respectively. The switching mechanisms of the tristate device are also proposed.

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Investigations of process factors in the sensitivity of embedded digital switching TSP

  • Han, Sang-Youn;Oh, Keun-Chan;Seong, Dong-Gi;Ham, Yeon-Sik;Lyu, Jae-Jin;Cho, Young-Je
    • 한국정보디스플레이학회:학술대회논문집
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    • 한국정보디스플레이학회 2009년도 9th International Meeting on Information Display
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    • pp.1531-1534
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    • 2009
  • Effect of process factors on the sensitivity of inner-type digital switching TSP was analyzed. From these results, we have successfully fabricated inner-type digital switching TSP embedded in 3.2-inch WQVGA PLS mode LCD panel. During many factors, TFT sensor structure for reducing the PI thickness and a separation distance of $0.3{\mu}m$ between the conductive column spacer (C/S) and TFT sensor were essential. Glass thickness and main C/S density were also important factors. This technology can be applied to wide angle of view hand-held phones, personal digital assistants (PDAs), and tablet PCs.

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Vertical Edge Based Algorithm for Korean License Plate Extraction and Recognition

  • Yu, Mei;Kim, Yong Deak
    • 한국통신학회논문지
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    • 제25권7A호
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    • pp.1076-1083
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    • 2000
  • Vehicle license plate recognition identifies vehicle as a unique, and have many applications in traffic monitoring field. In this paper, a vertical edge based algorithm to extract license plate within input gray-scale image is proposed. A size-and-shape filter based on seed-filling algorithm is applied to remove the edges that are impossible to be the vertical edges of license plate. Then the remaining edges are matched with each other according to some restricted conditions so as to locate license plate in input image. After license plate is extracted. normalized and segmented, the characters on it are recognized by template matching method. Experimental results show that the proposed algorithm can deal with license plates in normal shape effectively, as well as the license plates that are out of shape due to the angle of view.

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