• 제목/요약/키워드: Global Illumination

검색결과 87건 처리시간 0.026초

식물공장 각종광원의 방사조건과 LED조명의 활용에 관한 연구 (A Study on the Various Light Source Radiation Conditions and use of LED Illumination for Plant Factory)

  • 윤철구;최홍규
    • 조명전기설비학회논문지
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    • 제25권10호
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    • pp.14-22
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    • 2011
  • The artificial lights to be introduced for the plant factories is requiring the artificial light resources with minimizing the energy consumption to reduce the greenhouse gases which is a major cause of global warming, and maximizing the efficiency in photosynthesis effect light-wave range, in which the plants can be greatly grown and developed, and having the signal light-wave range for forming the light types. the best growing and developing environment for the plants has recently realized with utilizing the LED(Lighting Emitting Diode) lamps, as a environment-friendly green lamps, which can elevating the light efficiency with using only the specific light wave range. In this study, to provide the necessary lights for the full artificial light type of the plant factory, the following research/study and experiments has been conducting. experiments of the spectrum for each light sources, and LED, The intensity of illumination, Irradiance, Photosynthesis Photon Flux Density.

An Efficient Binarization Method for Vehicle License Plate Character Recognition

  • Yang, Xue-Ya;Kim, Kyung-Lok;Hwang, Byung-Kon
    • 한국멀티미디어학회논문지
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    • 제11권12호
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    • pp.1649-1657
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    • 2008
  • In this paper, to overcome the failure of binarization for the characters suffered from low contrast and non-uniform illumination in license plate character recognition system, we improved the binarization method by combining local thresholding with global thresholding and edge detection. Firstly, apply the local thresholding method to locate the characters in the license plate image and then get the threshold value for the character based on edge detector. This method solves the problem of local low contrast and non-uniform illumination. Finally, back-propagation Neural Network is selected as a powerful tool to perform the recognition process. The results of the experiments i1lustrate that the proposed binarization method works well and the selected classifier saves the processing time. Besides, the character recognition system performed better recognition accuracy 95.7%, and the recognition speed is controlled within 0.3 seconds.

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A NEW VEGETATION INDEX FOR REMOTE SENSING

  • Iisaka, Joji;Takako, Sakurai-Amano
    • 대한원격탐사학회:학술대회논문집
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    • 대한원격탐사학회 1999년도 Proceedings of International Symposium on Remote Sensing
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    • pp.256-261
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    • 1999
  • Global vegetation change is one of major global concerns. Remote sensing images provide an efficient and useful data source to estimate global vegetation covers, and a number of methods have been proposed to estimate them. Among them, the NDVI is one of the most popular indices, and it is_easy to calculate with simple image computing. However, this index is very much affected by the radiometric environment of sensing such as atmospheric conditions and the sun illumination angle. Therefore, it is not appropriate to apply the NDVI to investigate seasonal changes. This paper discusses these problems and proposes an alternative index, MODVI(Modified Vegetation Index), that is less affected by radiometric environment changes. An experiment was conducted to compare these two indices using temporal Landsat TM sub-scenes.

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색상기반 주목연산자를 이용한 정규화된 얼굴요소영역 추출 (Normalized Region Extraction of Facial Features by Using Hue-Based Attention Operator)

  • 정의정;김종화;전준형;최흥문
    • 한국통신학회논문지
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    • 제29권6C호
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    • pp.815-823
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    • 2004
  • 색상(hue) 기반 주목연산자와 조합누적투영함수(combinational integral projection function: CIPF)를 제안하여 조명변화에 강건하게 정규화된 얼굴요소영역을 추출하였다. 살색 필터를 도입하여 얼굴후보영역들을 추출하고, 거기에 색상과 대칭성에 기반한 주목연산자를 적용하여 조명변화에 강건하게 두 눈의 위치를 정확히 검출할 수 있도록 하였으며, 색상기반 눈 분산 필터로 눈을 검증하여 얼굴영역을 확인하였다. 또한, 색상과 밝기 성분을 조합한 조합누적투영함수를 사용하여 두 눈의 위치를 기준으로 조명변화나 수염의 존재유무에 둔감하게 눈썹 및 입의 수직위치를 구하고, 이를 바탕으로 정규화된 얼굴영역 및 그 요소영역을 추출하였다. AR 얼굴 데이터베이스[8]에 제안한 색상기반 주목연산자를 적용한 결과 기존 명도기반 주목연산자에 비해 약 39.3%의 눈 검출 성능향상을 보임으로써 조명방향 변화에 강건하게 정규화된 얼굴 및 그 요소영역을 일관성 있게 추출할 수 있음을 확인하였다.

깊이 정보를 이용한 영역분할 기반의 다시점 영상 조명보상 기법 (Illumination Compensation Algorithm based on Segmentation with Depth Information for Multi-view Image)

  • 강근호;고민수;유지상
    • 한국정보통신학회논문지
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    • 제17권4호
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    • pp.935-944
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    • 2013
  • 본 논문에서는 영상 분할을 이용한 다시점 영상의 조명보상 기법을 제안한다. 제안하는 기법에서는 깊이 정보를 이용하여 일정 거리에 따라 참조 영상의 깊이 영상을 레이어로 분리한다. 분리된 레이어에서 서로 다른 객체를 분리하기 위하여 각 레이어에 레이블링 과정을 수행한다. 레이블링 된 참조 영상의 깊이 영상은 3D 워핑 기법을 통하여 왜곡 영상의 시점으로 변환되고 레이블링 된 영역을 찾아 히스토그램을 이용한 조명 보상을 각 영역에서 독립적으로 수행한다. 3D 워핑으로 발생하는 가려짐 영역은 전역적인 방법을 이용하여 보상하게 된다. 다양한 실험을 통해 제안하는 기법으로 조명보상 전처리를 수행한 다시점 영상의 부호화 효율이 향상되는 것을 확인할 수 있었다.

Viewpoint Invariant Person Re-Identification for Global Multi-Object Tracking with Non-Overlapping Cameras

  • Gwak, Jeonghwan;Park, Geunpyo;Jeon, Moongu
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • 제11권4호
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    • pp.2075-2092
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    • 2017
  • Person re-identification is to match pedestrians observed from non-overlapping camera views. It has important applications in video surveillance such as person retrieval, person tracking, and activity analysis. However, it is a very challenging problem due to illumination, pose and viewpoint variations between non-overlapping camera views. In this work, we propose a viewpoint invariant method for matching pedestrian images using orientation of pedestrian. First, the proposed method divides a pedestrian image into patches and assigns angle to a patch using the orientation of the pedestrian under the assumption that a person body has the cylindrical shape. The difference between angles are then used to compute the similarity between patches. We applied the proposed method to real-time global multi-object tracking across multiple disjoint cameras with non-overlapping field of views. Re-identification algorithm makes global trajectories by connecting local trajectories obtained by different local trackers. The effectiveness of the viewpoint invariant method for person re-identification was validated on the VIPeR dataset. In addition, we demonstrated the effectiveness of the proposed approach for the inter-camera multiple object tracking on the MCT dataset with ground truth data for local tracking.

유비쿼터스 환경에서의 시각문맥정보인식에 대한 연구 (A Study on Visual Contextual Awareness in Ubiquitous Computing)

  • 한동주;김종복;이상훈;서일홍
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2004년도 학술대회 논문집 정보 및 제어부문
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    • pp.19-21
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    • 2004
  • In many cases, human's visual recognition depends on contextual information. We need to use effective feature information for performing vigorous place recognition to illumination, noise, etc. In the existing cases that use edge and color, etc., visual recognition doesn't cope effectively with real environment. To solve this problem, using natural marker, we improve the efficiency of place recognition.

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An Adaptive Photon Mapping in the Use of Automatic Differentiation

  • Namae, Takuya;Makino, Mitsunori
    • 대한전자공학회:학술대회논문집
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    • 대한전자공학회 2002년도 ITC-CSCC -2
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    • pp.991-994
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    • 2002
  • Photon mapping is an efficient global illumination technique for realistic image synthesis that has been developed in computer graphics. In this paper, an adaptive photon mapping in the use of automatic differentiation is proposed. Since the automatic differentiation is used when photons emit from the light sources through the scene, we can check the variation of surrounding shape. Therefore, we can decrease the number of photons and generate an image in relatively low computational cost.

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광학 광선추적 프로그램으로 보는 렌더링 (Study on the feasiblity on applying an Optical Ray-tracing SW to RenderingPage Summary)

  • 박승미;남기봉
    • 한국광학회:학술대회논문집
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    • 한국광학회 2008년도 하계학술발표회 논문집
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    • pp.393-394
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    • 2008
  • 컴퓨터 그래픽의 분야에서 Global illumination을 계산하는 과정은 우선 광선 추적 기법을 기반으로 한다. 가장 늦게 소개되어 사용자 층이 늘어나고 있는 photon mapping 기법도 scene rendering을 수행하기 이전에 광선 추적을 이용하여 photon의 공간적 분포를 미리 계산하는 과정을 활용한다. 본 고(稿)에서는 광학용으로 사용되는 SW를 scene rendering에 활용할 수 있는 가능성을 검증하였다.

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교통 신호등과 비전 센서의 위치 관계 분석을 통한 이미지에서 교통 신호등 검출 방법 (Traffic Light Detection Method in Image Using Geometric Analysis Between Traffic Light and Vision Sensor)

  • 최창환;유국열;박용완
    • 대한임베디드공학회논문지
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    • 제10권2호
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    • pp.101-108
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    • 2015
  • In this paper, a robust traffic light detection method is proposed by using vision sensor and DGPS(Difference Global Positioning System). The conventional vision-based detection methods are very sensitive to illumination change, for instance, low visibility at night time or highly reflection by bright light. To solve these limitations in visual sensor, DGPS is incorporated to determine the location and shape of traffic lights which are available from traffic light database. Furthermore the geometric relationship between traffic light and vision sensor is used to locate the traffic light in the image by using DGPS information. The empirical results show that the proposed method improves by 51% in detection rate for night time with marginal improvement in daytime environment.