• 제목/요약/키워드: illumination condition

검색결과 279건 처리시간 0.024초

Face Recognition Based on the Combination of Enhanced Local Texture Feature and DBN under Complex Illumination Conditions

  • Li, Chen;Zhao, Shuai;Xiao, Ke;Wang, Yanjie
    • Journal of Information Processing Systems
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    • 제14권1호
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    • pp.191-204
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    • 2018
  • To combat the adverse impact imposed by illumination variation in the face recognition process, an effective and feasible algorithm is proposed in this paper. Firstly, an enhanced local texture feature is presented by applying the central symmetric encode principle on the fused component images acquired from the wavelet decomposition. Then the proposed local texture features are combined with Deep Belief Network (DBN) to gain robust deep features of face images under severe illumination conditions. Abundant experiments with different test schemes are conducted on both CMU-PIE and Extended Yale-B databases which contain face images under various illumination condition. Compared with the DBN, LBP combined with DBN and CSLBP combined with DBN, our proposed method achieves the most satisfying recognition rate regardless of the database used, the test scheme adopted or the illumination condition encountered, especially for the face recognition under severe illumination variation.

태양전지 실리콘 웨이퍼의 표면결함 검출을 위한 구조적 하이브리드 조명시스템의 개발 및 최적 조건 선정 (Development of Structured Hybrid Illumination System and Optimum Illumination Condition Selection for Detection of Surface Defects on Silicon Wafer in Solar Cell)

  • 안병인;김경범
    • 대한기계학회논문집A
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    • 제36권5호
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    • pp.505-512
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    • 2012
  • 본 논문에서 태양전지 실리콘 웨이퍼 검사를 위해 광학스캐닝 메커니즘 기반 검사장비를 개발하였다. 그 중에서 다양한 결함검사 요구와 적절한 조명조건을 만족하는 구조적 하이브리드 조명시스템을 설계하였다. 그 다음으로 실험계획법을 이용하여 구조적 하이브리드 조명시스템의 최적 조명조건을 마스터 유리와 실리콘 웨이퍼에서 선정하였다. 마스터 유리에서 최적 조명조건은 B-강, BG-강, BR-강, BGR-강 이며, 실리콘 웨이퍼에서 최적조건은 R-중-B-중 이다. 이 최적조명조건을 적용하여 실리콘 웨이퍼 표면을 검사한 결과, 핀홀, 스크래치, 치핑 등 다수의 표면결함을 정확하게 검출하였다. 구조적 하이브리드 조명시스템은 태양전지 실리콘 웨이퍼 표면결함 검사에 유용하게 사용될 수 있다.

LED 조명의 색 온도에 따른 학습 성과의 객관적 평가 (Objective Evaluation of Learning Performance according to the Color Temperature of LED Illumination)

  • 지순덕;김채복
    • 교육시설 논문지
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    • 제18권2호
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    • pp.25-33
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    • 2011
  • This study performs the objective evaluation on simple comparison and calculation works by students under LED illumination conditions according to three types of color temperatures (7000K, 5000K, 3000K) in the classroom, Since the objective of this study is to develop an electric lighting conditions suitable for students in the classroom, the learning performance under three types of LED illumination conditions were analyzed. The 4 kinds of simple tests concerning with learning performance were developed and test results under natural light and LED illumination by 3 types of color temperatures were analyzed. There were differences by t-test in most cases among simple experiment results of different illumination conditions ($p{\leq}.05$). It was confirmed that illumination condition plays an important role when students simply compare words or perform arithmetic calculations. The experimental results of this study might be applied to designing better luminous environment.

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투과전자현미경에 타소질 불순물의 오염 최소화를 위한 실험 조건 (Experimentally Minimized Contaminative Condition of Carbonaceous Artifacts in Transmission Electron Microscope)

  • 김영민;최주형;송경;김양수;김윤중
    • Applied Microscopy
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    • 제39권1호
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    • pp.73-77
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    • 2009
  • Contaminative artifacts such as carbonaceous materials on carbon-coated microgrids are unavoidable, which is induced by electron beam exposure inside electron microscopes. This phenomenon raise a source to produce confusing information to the samples investigated by analytical TEM, which should be alleviated as much as possible. As experimental precautions for reducing this unwanted effect, the use of $LN_2$ cooled anti-contaminator and pre-illumination of electron beam at low magnification can be helpful. Nevertheless, we should be cautious to set an illumination condition for microanalysis because the contaminative effect is dependent with the types of irradiation situations, which is well known to be a decisive factor for causing the carbonaceous artifacts. Accordingly, it is necessary that optimal illumination to minimize the contaminative effect should be selected for improving the accuracy of microanalysis. In this paper, we introduce the practical method to determine the optimal illumination condition by evaluating the contaminative effect as a function of instrumental spot size, which is directly linked with electron current density.

개폐 개념의 높이 조절이 가능한 광선반 개발 연구 - 외부조도에 따른 광선반 성능평가 중심으로 (Research of the Development of a Height-adjustable light-shelf based on an Open and Closed Concept - Focusing on the light-shelf Performance Evaluation Depending on the External Illumination-)

  • 김수린;이행우;송석재;김용성
    • KIEAE Journal
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    • 제17권3호
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    • pp.83-90
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    • 2017
  • Purpose: With the increase in the energy consumption in the building sector, many studies have recently been conducted to address this issue. Due to its efficiency, diverse studies on a light-shelf, which is a natural lighting system, are in progress. However, there has been no research on the external illumination that determines the performance of a light-shelf. Therefore, the present study aimed to prepare the external illumination standard for securing the lighting performance of a light-shelf through the light-shelf performance evaluation based on a 1:1 scale testbed, and to suggest a height-adjustable light-shelf based on an open and closed concept for the case in which the lighting performance of the light-shelf significantly deteriorates, by collecting the external illumination. Method: In this study, a 1:1 scale testbed was established for performance evaluation, and the external illumination standard for securing the performance of the light-shelf was prepared by comparing the lighting performance of the light-shelf depending on the open and closed condition of the light-shelf and the external illumination. Result: 1) In this study, a light-shelf that can be opened or closed depending on the external illumination was suggested. As a result, the prospect right can be secured by creating the condition where there is no light-shelf installation by moving the light-shelf to the top of the window when the lighting performance is not secured. 2) In the summer solstice, the external illuminations appropriate for lighting energy reduction were more than 75,000 lx and 60,000 lx for the light-shelf width of 0.3 m and 0.6 m, respectively. 3) In the intermediate period, the external illumination appropriate for lighting energy reduction was 60,000 lx. In the winter solstice, making the condition where there is no light-shelf installation by closing the light-shelf would be appropriate. 4) Based on the aforementioned results, the external illumination standard for the opening and closing of the height-adjustable light-shelf based on an open and closed concept suggested in this study was 60,000 lx, and the light-shelf with a width of 0.6 m would be advantageous for lighting energy reduction.

고집광 태양전지의 비균등 조사에 의한 출력특성 (Output Power Characteristics of CPV Solar Cell due to Non-uniform Illumination)

  • 신구환;유광선;차원호;명로훈;김용식;강기환
    • 한국태양에너지학회:학술대회논문집
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    • 한국태양에너지학회 2011년도 춘계학술발표대회 논문집
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    • pp.269-274
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    • 2011
  • A solar cell is primary parts to produce electrical energy from the Sun. And, we can utilize those solar cells as a power generation system in home, factory, and so on. In order to make proper power, the solar cells are configured in series and parallel lay down. In condition of uniform illumination, the solar array will produce an enough power by photovoltaic effects from the solar cells. In case of non-uniform illumination on the solar cells, the power will be dramatically decreased compared to design. Fortunately, there were so many research outputs regarding the illumination effects on solar array. In this work, we tried to find out the non-uniform effects on unit CPV solar cell, because there were no research outputs for unit CPV solar cell considering illumination. The CPV solar cell was used in CPV system to make a power by the Sun. We chosen the triple junction solar cell of GaAsInP2Ge for simulation, which has a 30 % of conversion efficiency. By simulation, we obtained the output performance of CPV solar cells in condition of various illumination by using Hamming Window function. Its performance was degraded by 10 % to 50 % depending illumination conditions.

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배추 엽록체의 광계II 활성에 미치는 구리이온의 영향 (Effect of Cupric Ion on the PSII Activity in Isolated Chinese Cabbage Chloroplasts)

  • 박인호
    • Journal of Plant Biology
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    • 제30권3호
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    • pp.181-187
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    • 1987
  • Copper inhibited PSII-mediated O2 evolution (H2OlongrightarrowDCIP, H2OlongrightarrowSiMo) but not PSImediated O2 uptake(DCIP. Asc.longrightarrowMV) in isolated Chinese cabbage chloroplasts. Copper toxicity on PSII-mediated O2 evolution was higher at alkaline condition than at acidic condition and was inhanced by light illumination after copper treatment. The increased toxicity by light illumination was not recovered by subsequent dark treatment. The inhibitory effect of copper on H2OlongrightarrowDCIP reaction was higher than that on H2OlongrightarrowSiMo reaction. This result suggests that there may be another inhibitory site of copper on PSII other than water oxidizing side of PSII.

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Skin Color Extraction in Varying Backgrounds and illumination Conditions

  • Park, Minsick;Park, Chang-Woo;Kim, Won-ha;Park, Mignon
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 2001년도 ICCAS
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    • pp.162.4-162
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    • 2001
  • This paper presents a fuzzy-based method for classification skin color object in a complex background under varying illumination Parameters of fuzzy rule base are generated using a genetic algorithm(GA). The color model is used in the YCbCr color space. We propose a unique fuzzy system in order to accommodate varying background color and illumination condition This fuzzy system approach to skin color classification is discussed along with an overview of YCbCr color space.

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문서 영상의 전반사 영역 보정 기법 (Correction of Specular Region on Document Images)

  • 크리스티안 시몬;윌리엄;박인규
    • 한국방송∙미디어공학회:학술대회논문집
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    • 한국방송공학회 2013년도 추계학술대회
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    • pp.239-240
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    • 2013
  • The quality of document images captured by digital camera might be degraded because of non-uniform illumination condition. The high illumination (glare distortion) affects on the contrast condition of the document images. This condition leads to the poor contrast condition of the text in document image. So, optical character recognition (OCR) system might hardly recognize text in the high illuminated area. The method to increase the contrast condition between text (foreground) and background in high illuminated area is proposed in this paper.

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LED 조명의 색온도에 따른 집중도 및 시각적 변별력 평가 (Evaluation of Concentration and Visual Discrimination according to the Color Temperatures of LED Illumination)

  • 지순덕;김채복
    • 교육시설 논문지
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    • 제18권3호
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    • pp.23-33
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    • 2011
  • This study investigates the evaluation on simple comparison and seeking hidden figures works under LED illumination conditions according to three types of color temperatures (7000K, 5000K, 3000K) in the classroom, Since the objective of this study is to develop an electric lighting conditions suitable for students in the classroom, the performance of concentration and visual discrimination by students under three types of LED illumination conditions were analyzed. The 4 kinds of simple tests concerning with concentration and 2 types of tests for visual discrimination were developed, and test results under natural light and LED illumination by 3 types of color temperatures were analyzed. There were differences on concentration as well as visual discrimination performance in most cases by t-test ($p{\leq}0.05$). For further analysis among three types of color temperatures and natural light, ANOVA tests were performed. The test results shows that illumination condition plays an important role when students try to concentrate on simple comparison of characters, figures or colors and seek hidden figures. The experimental results of this study might be applied to designing better luminous environment.

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