• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 2003.11a
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• pp.3-8
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• 2003

Platforms of many railroad stations are crowded with passengers regardless of the time throughout day. But the intensity of illumination of the existing lightening systems are so low enough to make passengers feel inconvenience in using platforms. Consequently there exists high possibility of accidents in platforms of low illumination. Hence, for the safety and convenience of passengers, it is necessary to improve the luminous intensity of lightening system for platforms. This paper points out the problems of existing system and presents the method to improve it.

• 제어로봇시스템학회:학술대회논문집
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• 2001.10a
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• pp.42.1-42
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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.

• Journal of Biomedical Engineering Research
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• v.44 no.6
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• pp.450-464
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• 2023

Pulse oximetry, a non-invasive technique for evaluating blood oxygen saturation, conventionally depends on isolated measurements, rendering it vulnerable to factors like illumination profile, spatial blood flow fluctuations, and skin pigmentation. Previous efforts to address these issues through imaging systems often employed red and near-infrared illuminations with distinct profiles, leading to inconsistent ratios of transmitted light and the potential for errors in calculating spatial oxygen saturation distributions. While an integrating sphere was recently utilized as an illumination source to achieve uniform red and near-infrared illumination profiles on the sample surface, its bulkiness presented practical challenges. In this work, we have enhanced the pulse oximetry imaging system by transitioning illumination from an integrating sphere to a multi-wavelength LED configuration. This adjustment ensures simultaneous emission of red and near-infrared light from the same position, creating a homogeneous illumination profile on the sample surface. This approach guarantees consistent patterns of red and near-infrared illuminations that are spatially uniform. The sustained ratio between transmitted red and near-infrared light across space enables precise calculation of the spatial distribution of oxygen saturation, making our pulse oximetry imaging system more compact and portable without compromising accuracy. Our work significantly contributes to obtaining spatial information on blood oxygen saturation, providing valuable insights into tissue oxygenation in peripheral regions.

• Journal of the Ergonomics Society of Korea
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• v.27 no.2
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• pp.73-82
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• 2008

Currently an office in information society is advanced to a digitalized VDT office. The VDT office has a natural luminous system prioritizing visual perception and so importance of lighting design by artificial lighting is emphasized in the VDT office. The purpose of the study is to analyze Illumination and Luminance for lighting design by the standard of ergonomics in the VDT office. The study analyzed Illumination and Luminance in the main control room of an nuclear power plant needing a design of ergonomics ACR(Advanced Control Room) type Ling Ao phase II NPP MCR in Guangdong, China. The study examined the relativity of ACR characteristics to its operator's duties and set up an outline of lighting design, the standard of ergonomics and input data for the analysis. Thus, the study examined appropriateness with the standard of ergonomics setting up the analyzed Illumination and Luminance and drew a conclusion.

• The Journal of Korea Assosiation for Disability and Oral Health
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• v.3 no.2
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• pp.87-90
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• 2007

It's important that detect early caries of deciduous and permanent teeth to prevent dental caries and prevserve teeth, especially on proximal surface of deciduous teeth. The reason is that their prominent pulp horn lead to pulp treatment easily due to rapid caries progression. There are conventional exploring, visual inspection and radiographic exam for early caries detection. But, the standard method for diagnosing dental caries is subject and cavitation may be accelerated during exploring procedure. Caries can be diagnosed up to 40% mineral loss with radiograph. $DIFOTI^{(R)}$ (Digital Imaging Fiber-Optic TransIllumination) is diagnostic imaging system for early caries detection using fiber-optic illumination. It is possible that remineralize the tooth surface without tooth preparation and conserve the tooth structure by using $DIFOTI^{(R)}$.

• Journal of The Korean Digital Architecture Interior Association
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• v.13 no.4
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• pp.33-39
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• 2013

As lighting energy consumption in buildings occupies high ratio, technical researches to solve it have been constantly carried out. However, basic studies on light environment performance evaluation is actually deficient and only at a level of a simple illumination monitoring. Thus, this study has suggest a light environment energy performance evaluation based on actual residence environments to allow setting lighting interoperation and user required illumination. Conclusions from the study are as follows: 1) As the performance evaluation suggested by this study has not only derived lighting energy usage as well as monitored simple indoor illumination distribution, it is quantitative and allows derivation of visual results. 2) The performance evaluation suggested by this study allows inputs of user required illumination through the performance evaluation server, which is able to support for performance evaluations for various works and users. 3) This study has verified validity of the performance evaluation method by analyzing results of lighting energy reduction by executing performance evaluation on changes of light shelf that is a natural lighting system through the suggested performance evaluation method. This study is significant from a viewpoint that it has suggested a quantitative performance evaluation method on the basis of actual residence environments. Those researches concerned on the energy performance evaluation should be constantly progressed from an aspect that they are another solution of the energy problems.

• Journal of the Korea Furniture Society
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• v.26 no.4
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• pp.328-333
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• 2015

The museum is a important place to inform the value of various antiquities and relics. The museum, founded in domestic, were increased 90% in 2013 compared to 2006, and total number of including private museums were increased more than three times over the past decade. There are installing a variety of illumination and air-conditioning system, such as the spot lighting of exhibition explanation. But the exhibition explanation should not happen to visual perception disabilities by lighting. According to ICOM (International Council of Museum), it is stipulating that the museum should not to occur glare. However, we confirmed some occurred the glare and it was lack of previous studies about prevention plan. In this study, we verified occurrence of the glare by illumination angles and visitor's eye-level. The luminance values were determined by using DSLR camera and illuminometer. As a result, when illumination angle is 90 degree, the glare did not occurred by the luminance value ratio of over 0.167 regardless of eye-level. By contrast, the angle 30 degree was appeared glare with all level. And this study was compared luminance values that obtained through experiment and surveying.

• Atmosphere
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• v.28 no.3
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• pp.317-324
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• 2018

In this study, we review the ground-based whole-sky camera (WSC), which is developed to continuously capture day and night cloud images using the illumination data from a precision Lightmeter with a high temporal resolution. The WSC is combined with a precision Lightmeter developed in IYA (International Year of Astronomy) for analysis of an artificial light pollution at night and a DSLR camera equipped with a fish-eye lens widely applied in observational astronomy. The WSC is designed to adjust the shutter speed and ISO of the equipped camera according to illumination data in order to stably capture cloud images. And Raspberry Pi is applied to control automatically the related process of taking cloud and sky images every minute under various conditions depending on illumination data from Lightmeter for 24 hours. In addition, it is utilized to post-process and store the cloud images and to upload the data to web page in real time. Finally, we check the technical possibility of the method to observe the cloud distribution (cover, type, height) quantitatively and objectively by the optical system, through analysis of the captured cloud images from the developed device.

• Journal of the Ergonomics Society of Korea
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• v.28 no.4
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• pp.71-76
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• 2009

Effects of dark adaptation have large safety implications. This study was aimed to investigate the effects of varying illuminance and the size of critical detail on visual performance (i.e., time-to-detect) in a dark room environment. While adapting to the dark environment, ten subjects were asked to detect and answer simple numerical expressions under 9 experimental conditions (3 illuminance level $\times$ 3 target size). The ANOVA results revealed that the time-to-detect was significantly affected by both of the illumination level and the size of critical detail. As illumination increased from 10 lux to 20 lux, the time-to-detect was significantly declined. For the size of critical detail, 0.5/min size (i.e., equal to 2 minutes of visual angle) resulted in a shorter time-to-detect, as compared to 0.7/min size (i.e., equal to 1.6 minutes of visual angle). Potential applications of this research include the development of design guidelines for illumination and warning signs in poorly illuminated viewing environments.

• Current Optics and Photonics
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• v.4 no.4
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• pp.317-325
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• 2020

Accurate estimation of spatial frequencies and phases for illumination patterns are essential to reconstructing super-resolution images in structured illumination microscopy (SIM). In this manuscript, we propose the improved component cross-correlation (ICC) algorithm, which is based on optimization of the cross-correlation values of the overlapping information between various spectral components. Compared to other algorithms for spatial-frequency and phase determination, the results calculated by the ICC algorithm are more accurate when the modulation depths of the illumination patterns are low. Moreover, the ICC algorithm is able to calculate the spatial frequencies and phases simultaneously. Simulation results indicate that even if the modulation depth is lower than 0.1, the ICC algorithm still estimates the parameters precisely; the images reconstructed by the ICC algorithm are much clearer than those reconstructed by other algorithms. In experiments, our home-built SIM system was used to image bovine pulmonary artery endothelial (BPAE) cells. Drawing support from the ICC algorithm, super-resolution images were reconstructed without artifacts.