• 제목/요약/키워드: Light Region

검색결과 1,442건 처리시간 0.038초

The Effect of Light on Amorphous Silicon Thin Film Transistors based on Photo-Sensor Applications

  • Ha, Tae-Jun;Park, Hyun-Sang;Kim, Sun-Jae;Lee, Soo-Yeon;Han, Min-Koo
    • 한국정보디스플레이학회:학술대회논문집
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    • 한국정보디스플레이학회 2009년도 9th International Meeting on Information Display
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    • pp.953-956
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    • 2009
  • We have investigated the effect of light on amorphous silicon thin film transistors based photo-sensor applications. We have analyzed the instability caused by electrical gate bias stresses under the light illumination and the effect of photo-induced quasi-annealing on the instability. Threshold voltage ($V_{TH}$) under the negative gate bias stress with light illumination was more decreased than that under the negative gate bias stress without light illumination even though $V_{TH}$ caused by the light-induced stress without negative gate bias was shifted positively. These results are because the increase of carrier density in a channel region caused by the light illumination has the enhanced effect on the instability caused by negative gate bias stress. The prolonged light illumination led to the recovery of shifted VTH caused by negative gate bias stress under the light illumination due to the recombination of trapped hole charges.

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무인 자율주행을 위한 신호등의 검출과 인식 (Detection and Recognition of Traffic Lights for Unmanned Autonomous Driving)

  • 김장원
    • 한국정보전자통신기술학회논문지
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    • 제11권6호
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    • pp.751-756
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    • 2018
  • 본 연구는 입력 영상에서 교통 신호등을 검출하고, 신호등의 색상을 인식하며, 신호를 판별하여 무인 자율주행 차량이나 ITS(Intelligent Transportation System)에 적용할 수 있는 신호등 색상 인식 알고리즘을 제안하였다. 제안된 알고리즘은 교통신호등을 검출하기 위해 CEA(Canny Edge Algorithm)를 이용하여 외곽선을 추출하였고, 신호등의 색상을 인식하고 정확도를 높이기 위하여 HCT(Hough Circle Transform)를 적용하였다. 제안된 방법으로 주행도로상에서 획득한 스트림 영상에 적용한 결과, 우수한 신호등 색상 인식률을 확인할 수 있었다. 특히 입력영상에서 신호등이 존재할만한 ROI(Region Of Interest)로 구분하여 연산시간을 줄일 수 있었고, 신호등과 유사한 영역이라도 원이 검출되지 않거나 HSV 공간에서 V값이 낮아 후보영역에서 탈락시킴으로써 인식률의 정확도를 높일 수 있었다.

THEORY AND PRINCIPLES OF NEAR INFRARED SPECTROSCOPY

  • Barton, Franklin E.
    • 한국근적외분광분석학회:학술대회논문집
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    • 한국근적외분광분석학회 2001년도 NIR-2001
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    • pp.1012-1012
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    • 2001
  • The elegant early experiments of Herschel demonstrated that there is light after the visible spectrum in a region we call the near infrared (NIR). This was followed by the work which showed that the spectrum went further into what we call the mid infrared (MIR). The MIR has been used for many years as a qualitative and quantitative region to measure constituent values. The MIR region contains the fundamental vibrations which can be theoretically calculated from symmetry rules and harmonic oscillator equations. The NIR is not as straight forward because the region from 400-2500 nm does not contain any of the fundamental vibrations only combination bands and overtones. Over the past fifty years efforts to understand the NIR have largely been ignored while the quantitative aspects of the region have been utilized. This presentation will focus on the efforts to define terms for NIR, examine the calculation of combination bands and overtones and ways to interpret the spectra. The interpretation of the NIR has been aided greatly in recent years by the use of two dimensional spectroscopy which allows the correlation of bands in one spectral region with that of the NIR.

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Hot mirror를 이용한 고밀도 태양광의 광분리에 관한 기초실험 연구 (An Experimental Study on the Optical Separation of Highly Concentrated Sunlight)

  • 김영민;모용현;신상웅;오승진;천원기
    • 에너지공학
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    • 제23권4호
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    • pp.56-60
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    • 2014
  • 태양추적 장치에 장착된 집광기를 이용하여 획득한 고밀도의 태양광에너지는 적외선 범위 및 가시광선 범위의 두 파장 영역으로 분리할 수 있다. 적외선 범위의 파장은 열음향 시스템으로 활용할 수 있으며, 가시광선 범위의 파장은 조명시스템을 통하여 실내 태양광 조명에 활용할 수 있다. 즉, 집광된 태양광은 2차 반사경을 통해 광분리 장치로 입사되며, 입사된 태양광은 Hot mirror를 통하여 가시광선 영역과 적외선 영역으로 분리된다. 본 연구에서는 자연 태양광 및 실내의 인공광원을 대상으로 분리 실험을 하였다. 실내 광원 발생장치 실험에서 분리된 인공광원이 가시광선 영역의 파장은 400m부터 720m 범위이며, 적외선 영역의 파장은 620m부터 940m 범위이다. 또한, 태양추적 장치의 집광된 태양광을 통한 실험에서 가시광선 영역의 파장은 460m부터 680m 범위를 보이며, 적외선 영역의 파장은 620m부터 940m 범위인 것을 확인하였다.

RGB White Organic Light Emitting Diode with a Color Control Layer

  • Lee, Jeong-Ik;Chu, Hye-Yong;Yang, Yong-Suk;Lee, Mi-Do;Chung, Sung-Mook;KoPark, Sang-Hee;Hwang, Chi-Sun
    • 한국정보디스플레이학회:학술대회논문집
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    • 한국정보디스플레이학회 2006년도 6th International Meeting on Information Display
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    • pp.1587-1590
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    • 2006
  • Through the engineering of recombination region and energy transfer in organic light emitting device, blue and red light emitting device with good color stability has been successfully obtained. A Color control layer (CCL), which emits green light through the energy transfer from the emission layers, has been introduced into the blue and red light emitting device for RGB white OLED. The RGB white OLED showed the current efficiency of 13 cd/A and the CIE coordinates of (0.33, 0.38) at $1000\;cd/m^2$. The device exhibited very stable spectrum with respect to operating current density and the CIE coordinates varied from (0.34, 0.38) to (0.31, 0.37) for $100-22000\;cd/m^2$.

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A Continuous Regional Current-Voltage Model for Short-channel Double-gate MOSFETs

  • Zhu, Zhaomin;Yan, Dawei;Xu, Guoqing;Peng, Yong;Gu, Xiaofeng
    • JSTS:Journal of Semiconductor Technology and Science
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    • 제13권3호
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    • pp.237-244
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    • 2013
  • A continuous, explicit drain-current equation for short-channel double-gate (DG) MOSFETs has been derived based on the explicit surface potential equation. The model is physically derived from Poisson's equation in each region of operation and adopted in the unified regional approach. The proposed model has been verified with numerical solutions, physically scalable with channel length and gate/oxide materials as well as oxide/channel thicknesses.

Preprocessing for High Quality Real-time Imaging Systems by Low-light Stretch Algorithm

  • Ngo, Dat;Kang, Bongsoon
    • 전기전자학회논문지
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    • 제22권3호
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    • pp.585-589
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    • 2018
  • Consumer demand for high quality image/video services led to growing trend in image quality enhancement study. Therefore, recent years was a period of substantial progress in this research field. Through careful observation of the image quality after processing by image enhancement algorithms, we perceived that the dark region in the image usually suffered loss of contrast to a certain extent. In this paper, the low-light stretch preprocessing algorithm is, hence, proposed to resolve the aforementioned issue. The proposed approach is evaluated qualitatively and quantitatively against the well-known histogram equalization and Photoshop curve adjustment. The evaluation results validate the efficiency and superiority of the low-light stretch over the benchmarking methods. In addition, we also propose the 255MHz-capable hardware implementation to ease the process of incorporating low-light stretch into real-time imaging systems, such as aerial surveillance and monitoring with drones and driving aiding systems.

Fabrication of ZnO/TiO2 Nanoheterostructure and Its Application to Photoelectrochemical Cell

  • 송홍선;김희진;용기중
    • 한국진공학회:학술대회논문집
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    • 한국진공학회 2014년도 제46회 동계 정기학술대회 초록집
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    • pp.459.1-459.1
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    • 2014
  • Because both $TiO_2$ and ZnO has superior characteristic optically and electrically, there are various of research for these materials. However, they have large band gap energy which correspond with not visible light, but UV light. To make up for this disadvantage, Quantum dots (CdS, CdSe) which can absorb the visible light could be deposited on $ZnO/TiO_2$ nanostructure so that the the photoelectrochecmical cell can absorb the light that has larger region of wavelength. Both $TiO_2$ and ZnO can be grown to one-dimensional nanowire structure at low temperature through solutional method. Three-dimensional hierarcical $ZnO/TiO_2$ nanostructure is fabricated by applying these process. Large surface area of this structure make the light absorbed more efficiently. Through type 2 like-cascade energy band structure of nanostructure, the efficient separation of electron-hole pairs is expected. Photoelectrochemical charateristics are found by using these nanostructure to photoelectrode.

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산악용 경전철의 계획 및 시스템 선정에 관한 고찰 (Study for Planning and Guideline for Select the Reasonable Mountainous Light Rail Transit System)

  • 이덕영;이안호
    • 한국철도학회:학술대회논문집
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    • 한국철도학회 2008년도 춘계학술대회 논문집
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    • pp.1683-1688
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    • 2008
  • These days, in Korea, according to improving the standard living, people generally work 5 days a week and it results more leisure hours. On weekends or in specific season, travel to mountain region around the major city is much in demand, and, in case of public transportation, the demand exceeds the supply. So, people tend to go other places, even overseas, for their holidays. The situation in Korea reflects the needs for mountainous light rail transit system with the object of convenient and rapid transport of passengers. In this paper, the guideline for mountainous light rail transit planing is proposed, and the representative mountainous light rail transit system is analyzed to choose the proper mountainous light rail transit system which adapts the demand for transportation and the terrain in Korea.

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Guided Selection of Human Antibody Light Chains against TAG-72 Using a Phage Display Chain Shuffling Approach

  • Kim, Sang-Jick;Hong, Hyo-Jeong
    • Journal of Microbiology
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    • 제45권6호
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    • pp.572-577
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    • 2007
  • To enhance therapeutic potential of murine monoclonal antibody, humanization by CDR grafting is usually used to reduce immunogenic mouse residues. Most humanized antibodies still have mouse residues critical for antigen binding, but the mouse residues may evoke immune responses in humans. Previously, we constructed a new humanized version (AKA) of mouse CC49 antibody specific for tumor-associated glycoprotein, TAG-72. In this study, to select a completely human antibody light chain against TAG-72, guided selection strategy using phage display was used. The heavy chain variable region (VH) of AKA was used to guide the selection of a human TAG-72-specific light chain variable region (VL) from a human VL repertoire constructed from human PBL. Most of the selected VLs were identified to be originated from the members of the human germline VK1 family, whereas the VL of AKA is more homologous to the VK4 family. Competition binding assay of the selected Fabs with mouse CC49 suggested that the epitopes of the Fabs overlap with that of CC49. In addition, they showed better antigen-binding affinity compared to parental AKA. The selected human VLs may be used to guide the selection of human VHs to get completely human anti-TAG72 antibody.