• Title/Summary/Keyword: Standard Illumination

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A New Illumination Compensation Method based on Color Optimization Function for Generating 3D Volumetric Model (3차원 체적 모델의 생성을 위한 색상 최적화 함수 기반의 조명 보상 기법)

  • Park, Byung-Seo;Kim, Kyung-Jin;Kim, Dong-Wook;Seo, Young-Ho
    • Journal of Broadcast Engineering
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    • v.25 no.4
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    • pp.598-608
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    • 2020
  • In this paper, we propose a color correction technique for images acquired through a multi-view camera system for acquiring a 3D model. It is assumed that the 3D volume is captured indoors, and the position and intensity of the light is constant over time. 8 multi-view cameras are used, and converging toward the center of the space, so even if the lighting is constant, the intensity and angle of light entering each camera may be different. Therefore, a color optimization function is applied to a color correction chart taken from all cameras, and a color conversion matrix defining a relationship between the obtained 8 images is calculated. Using this, the images of all cameras are corrected based on the standard color correction chart. This paper proposed a color correction method to minimize the color difference between cameras when acquiring an image using 8 cameras of 3D objects, and experimentally proved that the color difference between images is reduced when it is restored to a 3D image.

Actual Conditions on the Illumination Environment of the Elderly House (고령자주택의 조명환경 실태조사)

  • An, Ok-Hee;Choi, Mi-Hyang
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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    • v.24 no.1
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    • pp.9-18
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    • 2010
  • This research surveys actual conditions in order to examine the lighting environments of the elderly's residential 50 households. The results is as following. First, The elderly indicated that they felt the living room and the kitchen are usual degree, dark only in bedrooms and rest rooms of brightness. And about satisfactory degree of residential illumination is being above of usual Satisfaction. Second, Problems of lighting environments of elderly's houses were brightness and management, when lighting environmental reconstruct, considered brightness and equipment superannuation, and they want the focus on brightness in the reconstruction. Third. Operating method of lighting was used almost overall lighting in bedroom and bathroom, overall lighting and part lighting are used together in kitchens. The living room has a lot of cases which uses only a general illumination, but the cases which overall lighting and part lighting are used together has occupied 40[%]. Fourth, An average Illuminance of the bedroom is 104.17[lx], an average unifonnity ratio is 60.22[%]. The livingroom's average is 116.15[lx], 51.48[%]. The sink's average is 236.40[lx], the table average is 160.73[lx] in the kitchen. The washstand's average is 109.81[lx], the chamber's average pot is 74.33[lx] in the bathroom. These results are generally darker than the standard.

Splitting of Surface Plasmon Resonance Peaks Under TE- and TM-polarized Illumination

  • Yoon, Su-Jin;Hwang, Jeongwoo;Lee, Myeong-Ju;Kang, Sang-Woo;Kim, Jong-Su;Ku, Zahyun;Urbas, Augustine;Lee, Sang Jun
    • Proceedings of the Korean Vacuum Society Conference
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    • 2014.02a
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    • pp.296-296
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    • 2014
  • We investigate experimentally and theoretically the splitting of surface plasmon (SP) resonance peaks under TE- and TM-polarized illumination. The SP structure at infrared wavelength is fabricated with a 2-dimensional square periodic array of circular holes penetrating through Au (gold) film. In brief, the processing steps to fabricate the SP structure are as follows. (i) A standard optical lithography was performed to produce to a periodic array of photoresist (PR) circular cylinders. (ii) After the PR pattern, e-beam evaporation was used to deposit a 50-nm thick layer of Au. (iii) A lift-off processing with acetone to remove the PR layer, leading to final structure (pitch, $p=2.2{\mu}m$; aperture size, $d=1.1{\mu}m$) as shown in Fig. 1(a). The transmission is measured using a Nicolet Fourier-transform infrared spectroscopy (FTIR) at the incident angle from $0^{\circ}$ to $36^{\circ}$ with a step of $4^{\circ}$ both in TE and TM polarization. Measured first and second order SP resonances at interface between Au and GaAs exhibit the splitting into two branches under TM-polarized light as shown in Fig. 1(b). However, as the incidence angle under TE polarization is increased, the $1^{st}$ order SP resonance peak blue-shifts slightly while the splitting of $2^{nd}$ order SP resonance peak tends to be larger (not shown here). For the purpose of understanding our experimental results qualitatively, SP resonance peak wavelengths can be calculated from momentum matching condition (black circle depicted in Fig. 2(b)), $k_{sp}=k_{\parallel}{\pm}iG_x{\pm}jG_y$, where $k_{sp}$ is the SP wavevector, $k_{\parallel}$ is the in-plane component of incident light wavevector, i and j are SP coupling order, and G is the grating momentum wavevector. Moreover, for better understanding we performed 3D full field electromagnetic simulations of SP structure using a finite integration technique (CST Microwave Studio). Fig. 1(b) shows an excellent agreement between the experimental, calculated and CST-simulated splitting of SP resonance peaks with various incidence angles under TM-polarized illumination (TE results are not shown here). The simulated z-component electric field (Ez) distribution at incident angle, $4^{\circ}$ and $16^{\circ}$ under TM polarization and at the corresponding SP resonance wavelength is shown in Fig. 1(c). The analysis and comparison of theoretical results with experiment indicates a good agreement of the splitting behavior of the surface plasmon resonance modes at oblique incidence both in TE and TM polarization.

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Design and Implementation of Sensibilities Lighting LED Controller using Modbus for a Ship (Modbus를 이용한 선박용 감성조명 LED 제어기의 설계 및 구현)

  • Jeong, Jeong-Soo;Lee, Sang-Bae
    • Journal of Navigation and Port Research
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    • v.39 no.4
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    • pp.299-305
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    • 2015
  • Modbus is a serial communications protocol, it has since become a practically standard communication protocol, and it is now a commonly available means of connecting industrial electronic devices. Therefore, it can be connected with all devices using Modbus protocol to the measurement and remote control on the ships, buildings, trains, airplanes and etc.. In this paper, we add the Modbus communication protocol to the existing lighting controller sensitivity to enable verification and remote control by external environmental factors, and also introduces a fuzzy inference system was configured by external environmental factors to control LED lighting. External environmental factors of temperature, humidity, illuminance value represented by the LED through a fuzzy control algorithm, the values accepted by the controller through the sensor. Modbus is using the RS485 Serial communication with other devices connected to the temperature, humidity, illumination and LED output status check is possible. In addition, the remote user is changed to enable it is possible to change the RGB values in the desired color change. Produced was confirmed that the LED controller output is based on the temperature, humidity and illumination.

Design Guide of Surface and Watertight LED Luminaires for Naval Vessels (함정용 노출.방수형 LED 조명기구의 설계 방안)

  • Kil, Gyung-Suk;Kim, Il-Kwon;Cho, Hyang-Eun;Kwon, Hyuk-Sang;Cho, Heung-Gi
    • Journal of Advanced Marine Engineering and Technology
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    • v.35 no.5
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    • pp.654-660
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    • 2011
  • This paper dealt with a design guide of LED luminaires to replace the surface and watertight fluorescent lamp (FL) fixtures for naval vessels. Several standards such as Korean Industrial Standard (KS), Korea Defence Standard (KDS) and US Military Standard (MIL) were compared in terms of safety and performance of lighting fixtures. The electrical and optical characteristics like power consumption, total luminous flux, and illumination distribution of the FL fixtures were experimentally analyzed to acquire design rules for LED luminaires. Based on the results, four types of LED luminaires were fabricated, and we proposed a design guide of LED luminaires for naval vessels which save power consumption of 44~51 [%] and increase total luminous flux of 8~13 [%].

An Approach to the Theoretical Design Standard and Effective Practice of Museum Showcase Lighting (진열장 조명의 이론적 기준과 시설에 대한 고찰)

  • Kim, Hong-Bum
    • 보존과학연구
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    • s.17
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    • pp.123-160
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    • 1996
  • There have been many studies and experiments regarding exhibition lighting. Many experiments on photochemical damaging effect and visibility resulted in a practice limited to assigning light levels and adjusting annual exposure time. The three damaging factors to the artifacts are intrinsicsusceptibility to absorb radiant energy, spectral distribution of light source and intensity of illumination and time of exposure. Dividing all the artfacts into three categories to suggest a recommended illuminance level causes some problems. Blue wool, for example, used as the reference material for susceptibility, is not a standard material representing museum artifacts. In the most light sensitive category, ISO class I or anything below have been excluded. The exposure time of one soure can be three times more than another sourece. The spectral distribution of the light source and the relative spectral responsibility of the artifact are not considered in the practice. So in case of very light sensitive material, the recommended illuminance is only the referring value and it is indispensable to check the characteristic of susceptibility of each artifacts. Daylighting is prevailing method to solve the psychological need of the visitors. However, it sould transparent, and should not diffused, and the green-house effect must be considered. llluminance uniformity should based on the maximum illuminance to handle the limitation of exposure for the conservation of a large sensitive object such as a painting. Damage index is not absolute reference for selecting the lighting source because it is experimented from the paper of low grade then calculated. Visibility should be increased by reducing the visual noiseand by planning of appropriate luminance contrast. This paper reviews the problems with the previous studies and experiment sand the current exhibition lighting design practice. The plan for museum showcase lighting is to check the susceptibility and to raise the visibility simultaneously.

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Calibration of Omnidirectional Camera by Considering Inlier Distribution (인라이어 분포를 이용한 전방향 카메라의 보정)

  • Hong, Hyun-Ki;Hwang, Yong-Ho
    • Journal of Korea Game Society
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    • v.7 no.4
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    • pp.63-70
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    • 2007
  • Since the fisheye lens has a wide field of view, it can capture the scene and illumination from all directions from far less number of omnidirectional images. Due to these advantages of the omnidirectional camera, it is widely used in surveillance and reconstruction of 3D structure of the scene In this paper, we present a new self-calibration algorithm of omnidirectional camera from uncalibrated images by considering the inlier distribution. First, one parametric non-linear projection model of omnidirectional camera is estimated with the known rotation and translation parameters. After deriving projection model, we can compute an essential matrix of the camera with unknown motions, and then determine the camera information: rotation and translations. The standard deviations are used as a quantitative measure to select a proper inlier set. The experimental results showed that we can achieve a precise estimation of the omnidirectional camera model and extrinsic parameters including rotation and translation.

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The Study about the Differential compression based on the ROI(Region Of Interest) (ROI(Region Of Interest)기반의 차등적 이미지 압축에 관한 연구)

  • Yun, Chi-Hwan;Ko, Sun-Woo;Lee, Geun-Ho
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.18 no.3
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    • pp.679-686
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    • 2014
  • Recently, users can get countless images and videos by network. So, the compression technology of image and video is researched more and more. However, the situation which is the interested range of the image is occurred. For instance, since the region of face is more important than background, the image compression technology bases on the region of interest (ROI) is necessary, in the ATM environment. In this research, given the human visual system, which are not sensitive to illumination variations at very dark and light regions of image, we calculate the standard deviation of block and use this value to define the ROI. In encoding process, the relatively high quality can be obtained at the ROI and the relatively low quality can be obtained at the non ROI. In proposed scheme, the feature which is the encoding process according to subjectively image quality can be demonstrated. Finally, this proposed scheme is applied to JPEG standard. The experimental results demonstrate that proposed scheme can achieve better image quality at the high compression ratio.

Design of a Reflector for LED Light Sources with Asymmetric Light Distribution (비대칭 배광을 갖는 LED 스포츠 조명 반사경 설계)

  • Seo, Jin-Hee;Jo, Ye-Ji;Lee, Hyun-Hwa;Seo, Jae-Yeong;Jun, Won-Kyoun;Lee, Han-Yul;Kang, Dong-Hwa;Jung, Mee-Suk
    • Korean Journal of Optics and Photonics
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    • v.29 no.6
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    • pp.253-261
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    • 2018
  • In this paper, we study a method of designing a reflector for LED light sources with an asymmetric light distribution. In a sports game, lighting with a symmetric distribution makes the athlete and spectators look directly at the light source, so it can cause glare. We derive the optimal tilt angle and design a reflector with asymmetric light distribution to solve these problems. Afterward, performance is analyzed according to the tennis-court lighting standard, and is confirmed to meet the class 1 European standard.

Skin Pigment Recognition using Projective Hemoglobin- Melanin Coordinate Measurements

  • Yang, Liu;Lee, Suk-Hwan;Kwon, Seong-Geun;Song, Ha-Joo;Kwon, Ki-Ryong
    • Journal of Electrical Engineering and Technology
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    • v.11 no.6
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    • pp.1825-1838
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    • 2016
  • The detection of skin pigment is crucial in the diagnosis of skin diseases and in the evaluation of medical cosmetics and hairdressing. Accuracy in the detection is a basis for the prompt cure of skin diseases. This study presents a method to recognize and measure human skin pigment using Hemoglobin-Melanin (HM) coordinate. The proposed method extracts the skin area through a Gaussian skin-color model estimated from statistical analysis and decomposes the skin area into two pigments of hemoglobin and melanin using an Independent Component Analysis (ICA) algorithm. Then, we divide the two-dimensional (2D) HM coordinate into rectangular bins and compute the location histograms of hemoglobin and melanin for all the bins. We label the skin pigment of hemoglobin, melanin, and normal skin on all bins according to the Bayesian classifier. These bin-based HM projective histograms can quantify the skin pigment and compute the standard deviation on the total quantification of skin pigments surrounding normal skin. We tested our scheme using images taken under different illumination conditions. Several cosmetic coverings were used to test the performance of the proposed method. The experimental results show that the proposed method can detect skin pigments with more accuracy and evaluate cosmetic covering effects more effectively than conventional methods.