• Title/Summary/Keyword: illumination change

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A Study on the Convertible Emergency Lighting Fixture in Consideration of Dark Adaptation (암순응을 고려한 겸용형 비상조명등에 관한 연구)

  • Yum, Sung-Bae;Yoon, Cheol-Gu;Lee, Jung-Eun;Shin, Hye-Young;Song, Young-Joo
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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    • v.25 no.4
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    • pp.24-29
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    • 2011
  • When an emergency light turns on due to a blackout, the intensity of illumination is drastically changed from hundreds [1x] to 1.0[1x]. This sharp change of illumination intensity not only lowers the darkness adaptation of the eye, it also degrades the obstacle cognitive ability of the evacuees, resulting in secondary critical accidents due to anxiety, and fear. Thus, this study proposed a convertible emergency lighting fixture that controls the rate of speed of light in two stages by time with darkness adaptation of the eye in consideration. In addition, the effect of such emergency light is verified by suggesting an illumination simulation without increasing the number of light or capacity of battery to make it economically feasible.

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

  • Lee, Seung-Min;Lee, Seong-Jin;Choi, Gi-Seung;Lee, Jong-Chan;Park, Dae-Hee
    • Proceedings of the KIEE Conference
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    • 2006.07a
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    • pp.609-610
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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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Optical, Thermal property by Applied PCB Structure design (PCB 구조적 설계에 따른 LED Module의 열적 광학적 특성)

  • Lee, Seung-Min;Lee, Seong-Jin;Choi, Gi-Seung;Lee, Jong-Chan;Park, Dae-Hee
    • Proceedings of the KIEE Conference
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    • 2006.07d
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    • pp.2241-2242
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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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Light Effects on the Bias Stability of Transparent ZnO Thin Film Transistors

  • Shin, Jae-Heon;Lee, Ji-Su;Hwang, Chi-Sun;KoPark, Sang-Hee;Cheong, Woo-Seok;Ryu, Min-Ki;Byun, Chun-Won;Lee, Jeong-Ik;Chu, Hye-Yong
    • ETRI Journal
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    • v.31 no.1
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    • pp.62-64
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    • 2009
  • We report on the bias stability characteristics of transparent ZnO thin film transistors (TFTs) under visible light illumination. The transfer curve shows virtually no change under positive gate bias stress with light illumination, while it shows dramatic negative shifts under negative gate bias stress. The major mechanism of the bias stability under visible illumination of our ZnO TFTs is thought to be the charge trapping of photo-generated holes at the gate insulator and/or insulator/channel interface.

Study On the Robustness Of Four Different Face Authentication Methods Under Illumination Changes (얼굴인증 방법들의 조명변화에 대한 견인성 연구)

  • 고대영;천영하;김진영;이주헌
    • Proceedings of the IEEK Conference
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    • 2003.07e
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    • pp.2036-2039
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    • 2003
  • This paper focuses on the study of the robustness of face authentication methods under illumination changes. Four different face authentication methods are tried. These methods are as follows; Principal Component Analysis, Gaussian Mixture Models, 1-Dimensional Hidden Markov Models, 2-Dimensional Hidden Markov Models. Experiment results involving an artificial illumination change to face images are compared with each others. Face feature vector extraction method based on the 2-Dimensional Discrete Cosine Transform is used. Experiments to evaluate the above four different face authentication methods are carried out on the Olivetti Research Laboratory(ORL) face database. For the pseudo 2D HMM, the best EER (Equal Error Rate) performance is observed.

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

  • Lee, Seung-Min;Lee, Seong-Jin;Choi, Gi-Seung;Lee, Jong-Chan;Park, Dae-Hee
    • Proceedings of the KIEE Conference
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    • 2006.07b
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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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Vehicle Identification Number Recognition using Edge Projection and PCA (에지 투영과 PCA를 이용한 차대 번호 인식)

  • Ahn, In-Mo;Ha, Jong-Eun
    • Journal of Institute of Control, Robotics and Systems
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    • v.17 no.5
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    • pp.479-483
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    • 2011
  • The automation of production process is actively expanding for the purpose of the cost reduction and quality assurance. Among these, automatic tracking of the product along the whole process of the production is also important topic. Typically this is done by adopting OCR technology. Conventional OCR technology operates well on the rather good quality of the image like as printed characters on the paper. In industrial application, IDs are marked on the metal surface, and this cause the height difference between background material and character. Illumination systems that guarantee an image with good quality may be a solution, but it is rather difficult to design such an illumination system. This paper proposes an algorithm for the recognition of vehicle's ID characters using edge projection and PCA (Principal Component Analysis). Proposed algorithm robustly operates under illumination change using the same parameters. Experimental results show the feasibility of the proposed algorithm.

Improvement of Lighting Control System for Tunnel (터널 조명 제어장치의 성능개선)

  • Eo, Ik-Soo
    • Proceedings of the KIEE Conference
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    • 2003.07c
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    • pp.1964-1966
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    • 2003
  • Lighting in the tunnel makes for safe driving of cars taking into account of change in perception arisen in the sight of drivers of cars entering into and passing tunnel, drivers' mental reaction and unique circumstances of a tunnel. There are many variables to satisfy safe driving in the tunnel. Since tunnels are mostly located in the mountainous area and illumination at the approach part differs largely depending on the surrounding circumstances, a standard different from that of common lighting is applied. An accidentin the tunnel, which involves same danger as in underground, may lead to a large mishap. Therefore, control by sensors inside and outside of tunnel ensures prevention of an accident through control of illumination at the approach part and inside of tunnel. It is very important in the aspect of saving energy since such control is available to reduce depreciation factor resulted from early excessive intensity of illumination.

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Environmental save of the Ondal cave and the management plan of an electric saving (온달동굴의 환경보존과 전기절약의 관리 방안)

  • Yoon, Jung-Mo
    • Journal of the Speleological Society of Korea
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    • no.88
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    • pp.26-30
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    • 2008
  • The black pollution that was able to include green pollution to appear for the intensity of light by an illumination institution is what after all I cannot ignore, and it may be said that chase thing damage by the isolation action that is white pollution done a long story in this outside a certain range by air quality change, dried present situation is really the environmental disruption by development and a damage phenomenon. If I am replaced in winker and I install a sensor light in the outlet by addition and use the electricity illumination that I installed for a tourist in the cave, it is expected that I can be available all the time that it is possible for electricity reduction more than the present and watches tourist passage plan private business Electric illumination in the cave for the environmental save in the cave because it is possible for more electricity reduction to be particularly off-season than on-season.

Study on the Color Changing of Pine by Accelerated Weathering Test (소나무재의 촉진열화실험에 따른 재색변화에 대한 연구)

  • Kim, Gwang-Chul
    • Journal of the Korea Furniture Society
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    • v.23 no.2
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    • pp.152-162
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    • 2012
  • The color changing of the wood surface was tested by accelerated weathering test that can simulate the outdoor condition with short period. In early parts of accelerated weathering test, weight and volume of specimen all were increased due to the moisture evaporation by its high temperature and illumination level, but weight and volume of specimen all were decreased from middle parts to last. However, significancy showed between control group and accelerated weathering test group in terms of weight and volume. According to the results of color-difference meter, in the early parts of the accelerated weathering test lightness, redness and yellowness all showed a clear increasing or decreasing trend. However, after three weeks all values were almost never change. Until the early parts of the test, lightness was decreased and there was not a considerable change after three weeks in the test. Redness showed a some change in early parts of the test, but this also showed not great change after middle parts of the test as like lightness. Yellowness also showed same pattern. These results could be verified through the visual inspection. As like weight and volume, significancy showed between control group and accelerated weathering test group in terms of color-difference test. In all accelerated weathering test group, color-differences of after test was lower than that of before test. To correctly analyze this cause, more additional research will be need on each of temperature, humidity and illumination factors.

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