• 제목/요약/키워드: Intensity of illumination

검색결과 399건 처리시간 0.028초

영농형 태양광 발전 솔라쉐어링에 따른 하부 일사량 변화의 해석 및 분석 (Simulation and Analysis of Solar Radiation Change Resulted from Solar-sharing for Agricultural Solar Photovoltaic System)

  • 이상익;최진용;성승준;이승재;이지민;최원
    • 한국농공학회논문집
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    • 제62권5호
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    • pp.63-72
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    • 2020
  • Solar-sharing, which is an agricultural photovoltaic system installing solar panels on the upper part of crop growing field, has especially drawn attention. Because paddy fields for cultivating crops are large flat areas, there have been various attempts to utilize solar energy for solar photovoltaic as well as growth of crops in agriculture. Solar-sharing was first proposed in Japan, and has been actively studied for optimization and practical uses. The domestic climate differs from the climate conditions in which the solar-sharing has been widely studied, therefore, it is required to develop the solar-sharing technology suitable for the domestic climate. In this study, a simulation model was developed to analyze the change of solar radiation resulted from the solar-sharing installation. Monthly solar illumination intensity and the change of illumination intensity according to the various conditions of solar panel installation were simulated. The results of monthly illumination analysis differed by altitude of the sun, which was related to season. In addition, it was analyzed that the monthly illumination decreased by up to 42% due to solar-sharing. Accordingly, it is recommended that solar-sharing should be installed as a way to maximize the efficiency of solar photovoltaic system while minimizing the decrease in solar radiation reaching the crops.

저 조도 영상에서의 말레이시아 차량 번호판 인식 (Malaysian Vehicle License Plate Recognition in Low Illumination Images)

  • 김진호
    • 한국콘텐츠학회논문지
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    • 제13권10호
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    • pp.19-26
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    • 2013
  • 말레이시아 차량 번호판에는 플라스틱으로 제작된 영문 및 숫자들이 엠보싱 형태로 부착되어있으며 수평 수직방향 문자들 사이 간격이 조밀하게 배치된 경우가 많다. 따라서 조도가 낮은 차량 영상에서는 번호판 문자 획 정보 추출이 어려워질 수 있다. 본 논문에서는 저 조도에서 촬영된 말레이시아 차량 영상에서 번호판을 인식하는 알고리즘을 제안하였다. 저 조도에서 촬영된 차량 영상에서도 문자 획 연결 요소를 정확하게 추출하기 위해 DoG 필터링 기반 문자 획 생성 기법을 도입하였다. 문자 획 연결요소 해석을 통한 번호판 후보 영역을 추정한 다음 문자 영역을 분할하고 인식을 하였다. 쿠알라룸푸르 도로상에서 조명이 부착되지 않은 IR 카메라를 사용하여 주야로 촬영한 6,046장의 차량 영상을 대상으로 번호판 인식 실험을 수행하였다. 제안된 알고리즘을 이용하여 실험해 본 결과 번호판 인식 성능이 96.1%로 나타났다.

머신 비전 라인 스캔 카메라를 위한 라인 스캔 광원의 제어 특성에 관한 연구 (A Study on the Control Characteristics of Line Scan Light Source for Machine Vision Line Scan Camera)

  • 김태화;이천
    • 한국전기전자재료학회논문지
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    • 제34권5호
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    • pp.371-381
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    • 2021
  • A machine vision inspection system consists of a camera, optics, illumination, and image acquisition system. Especially a scanning system has to be made to measure a large inspection area. Therefore, a machine vision line scan camera needs a line scan light source. A line scan light source should have a high light intensity and a uniform intensity distribution. In this paper, an offset calibration and slope calibration methods are introduced to obtain a uniform light intensity profile. Offset calibration method is to remove the deviation of light intensity among channels through adding intensity difference. Slope calibration is to remove variation of light intensity slope according to the control step among channels through multiplying slope difference. We can obtain an improved light intensity profile through applying offset and slope calibration simultaneously. The proposed method can help to obtain clearer image with a high precision in a machine vision inspection system.

조도변화가 시기능 성분에 미치는 영향 (Effects of Variation of Illumination on Visual Function Factors)

  • 김다영;김상엽;조현국;문병연
    • 한국안광학회지
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    • 제20권2호
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    • pp.195-200
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    • 2015
  • 목적: 조도변화가 시기능에 미치는 영향을 알아보고자 하였다. 방법: 평균나이 $23.93{\pm}1.59$세 40명(남 21, 여 19)을 대상으로 시표면 조도를 5, 50, 200, 500 및 800 lx로 조정하여 각 조도 상태에서 조절력, 폭주근점, 원거리 및 근거리 사위, 원거리 및 근거리 융합버전스, 상대조절력, 조절래그를 측정하였다. 결과: 시표면의 조도가 감소함에 따라 조절력은 유의하게 감소하였고(p<0.05), 조절래그는 감소하였고, 폭주근점은 멀어졌으며, 수평사위는 내편위의 경향을 보였다. 음성융합버전스는 조도가 감소함에 따라 분리점과 회복점이 감소하는 경향을 보인 반면 양성융합버전스는 분리점이 증가하는 경향을 보였다. 음성 및 양성상대조절력의 경우 조도가 감소함에 따라 유의한(p<0.05) 감소를 보였다. 결론: 임상현장에서 시기능 검사는 환자의 생활환경 및 직업 등을 고려한 적절한 조도 수준에서 수행되어야 할 것으로 사료된다.

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

  • 염성배;윤철구;이정은;신혜영;송영주
    • 조명전기설비학회논문지
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    • 제25권4호
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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.

3D Particle Image Detection by Using Color Encoded Illumination System

  • Kawahashi M.;Hirahara H.
    • 한국가시화정보학회:학술대회논문집
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    • 한국가시화정보학회 2001년도 Proceedings of 2001 Korea-Japan Joint Seminar on Particle Image Velocimetry
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    • pp.100-107
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    • 2001
  • A simple new technique of particle depth position measurement, which can be applied for three-dimensional velocity measurement of fluid flows, is proposed. Two color illumination system that intensity is encoded as a function of z-coordinate is introduced. A calibration procedure is described and a profile of small sphere is detected by using the present method as preliminary test. Then, this method is applied to three-dimensional velocity field measurement of simple flow fields seeded with tracer particles. The motion of the particles is recorded by color 3CCD camera. The particle position in the image plane is read directly from the recorded image and the depth of each particle is measured by calculation of the intensity ratio of encoded two color illumination. Therefore three-dimensional velocity components are reconstructed. Although the result includes to some extent error, the feasibility of the present technique for three-dimensional velocity measurement was confirmed.

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서울지역 학교 교실의 실내환경 조사연구 (A Study on the Indoor Environment of school classrooms in Seoul area)

  • 최한영
    • 환경위생공학
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    • 제18권2호
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    • pp.67-74
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    • 2003
  • In 15 schools where were chosen each location (East, West, South, North, Central) of Seoul area, 9 items were measured such as thermo circumstance(temperature, relative humidity, air current, intensity of illumination) particulate matter, carbon monoxide, sulfur dioxide, and nitrogen dioxide being based on the school indoor environment standard. It was showed that indoor temperature, relative humidity and air movement were suitable in comparison with school indoor environment standard. Intensity of illumination was suitable in comparison with all schools, only exception 2 schools. In all investigated schools were adequate for carbon monoxide, sulfur dioxide and nitrogen dioxide, in which each indoor environment standard (10ppw, 0.25ppm/hr, 0.15ppm/hr), but in 5 schools the carbon dioxide were exceeded for standard limit 1,000ppm of Korea. Indoor concentration of dust(PM-10) induced from respiration dust the standard of Korea ($150{\mu}g/m^3$) at all schools.

상이한 스펙트럼을 가지는 객체간의 RGB 색상 차이를 최대학화기 위한 최적조명 (Optimal Illumination for Maximizing the RGB Distance between Objects with Different Spectra)

  • 서동균;이문현;서병국;박종일
    • 대한의용생체공학회:의공학회지
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    • 제30권3호
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    • pp.263-269
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    • 2009
  • An object's color and intensity are determined by its spectral reflectance and illumination. Therefore, the illumination plays a key role in forming the appearance of the object in a scene. In this paper, we focus on color distinction of objects and derive the optimal illumination conditions to maximize the distance between objects in the RGB color space. As a practical approach the optimal illumination is composed by deriving the optimal linear combinations given a set of LED light sources. The effectiveness of our approach is shown through experimental results using an endoscope system.

Photon-counting digital holography

  • Hayasaki, Yoshio
    • 한국광학회:학술대회논문집
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    • 한국광학회 2009년도 창립 20주년기념 특별학술발표회
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    • pp.165-166
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    • 2009
  • A hologram was recorded with two-dimensional scanning of an optical fiber connected to a single-photon counting detector under ultra-weak illumination. The object image was clearly reconstructed in a computer from the hologram. The dependence of hologram quality on the illumination light intensity was estimated.

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조명 변화에 강인한 얼굴 검출을 위한 좌우대칭 평균화와 단순회귀분석 보정기법 (Bilateral Symmetry Averaging and Simple Regression Analysis for Robust Face Detection Against Illumination Variation)

  • 조치영;김수환
    • 한국콘텐츠학회논문지
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    • 제6권12호
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    • pp.21-28
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    • 2006
  • 형판 정합 기반의 얼굴 검출 시스템에서 획득된 이미지에 대한 명암 정규화 및 영상 보정을 위해 보통 히스토그램 평활화 등을 사용한다. 이 방법은 조명 변화에 의해 발생한 이미지의 부분 명암 왜곡에는 효과적이지 못하다는 것이 알려져 있다. 본 논문에서는 다양한 방향의 조명에 의한 명암 왜곡을 효과적으로 보정하는 전처리 기법을 제시한다. 이 기법은 얼굴의 좌우대칭성을 이용한 좌우대칭 평균화와 단순회귀분석을 이용한 세로 방향 명암 보정을 결합한 것이다. 실험 결과 이 기법은 기존의 방식보다 높은 검출성능을 보일 뿐만 아니라 얼굴의 후보 개수도 현저하게 감소하는 것으로 나타났다.

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