• Journal of the Semiconductor & Display Technology
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• v.10 no.3
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• pp.89-94
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• 2011

The image identification methodology associates an image with a unique identifiable representation. Whenever the methodology regenerates an identifier for the same image, moreover, the newly created identifier needs to be consistent in terms of representation value. In this paper, we discuss a methodology for image identifier generation utilizing luminance correlation. We furthermore propose a method for performance enhancement of the image identifier generation. We also demonstrate the experimental evaluations for uniqueness and similarity analysis and performance improvement that have shown favorable results.

• Proceedings of the Korean Society of Broadcast Engineers Conference
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• 2013.11a
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• pp.3-5
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• 2013

We proposed a method for increasing visibility of dehazed images by enhancing luminance component of dehazed image. For this purpose, we analyze shape of luminance histogram in multi bunches and observe that increasing visibility those bunches does not bear over contrast enhancement. From the analysis and observation, histogram equalization intends to increase visibility of each bunch with less computation.

• International Journal of Highway Engineering
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• v.18 no.4
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• pp.69-75
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• 2016

PURPOSES : In this study, we evaluated changes in the retroreflectivity and luminance of phosphorescent road line markings with changes in glass beads and line marking thickness. METHODS : The color of line markings affects their retroreflectivity. Using a chromaticity test, we conducted the analysis of whether phosphorescent road line markings adhered to the "KS M 6080" standard. Then, we measured the dry retroreflectivity and wet retroreflectivity for various glass bead refractive indices. We conducted wet retroreflectivity test using the EN 1436 standard as the basis. We also conducted luminance tests for different glass bead refractive indices and line marking thicknesses. RESULTS : 1. Phosphorescent road line markings specimens satisfied the "KS M 6080" standard. 2. In dry retroreflectivity test, phosphorescent road line markings sprayed with glass beads satisfied the national police agency standard ($240mcd/(m^2{\cdot}Lux)$). Wet retroreflectivity test results showed that except for one type of No.1 glass beads, phosphorescent road line markings specimens sprayed with glass beads of one type of No.3 and two types of No.1 satisfied the national police agency standard ($100mcd/(m^2{\cdot}Lux)$). 3. Phosphorescent road line markings had higher retroreflectivity than non-phosphorescent road line markings in the dry condition. 4. Phosphorescent road line markings sprayed with glass beads demonstrated improved luminance. Luminance increased with higher glass bead refractive index and with increased line marking thickness. However, when the thickness crossed a certain threshold, phosphorescence ceased to increase; this is a characteristic of the phosphorescence phenomenon. CONCLUSIONS : Visibility across short distances can be ensured when phosphorescent road line markings are sprayed with glass beads, because of the retroreflection phenomenon. It is also possible to ensure far visibility using phosphorescent road line markings.

• 한국정보디스플레이학회:학술대회논문집
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• 2007.08b
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• pp.1185-1188
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• 2007

The address discharge characteristics by the various scan-low and common-bias voltages are investigated based on measured address discharge time lags and $V_t$ close-curve analysis. The scan-low voltages are changed under the same voltage difference between the X and Y electrodes during an address period. As the voltage difference between the scan and address electrodes is increased during an address period, the address discharge time lag is shortened but the background luminance is increased. It is found that the improved address discharge characteristics is caused by the effect of the higher external applied voltage during an address period than the accumulated wall charges during a reset period and the high background luminance can be prevented by applying an address-bias voltage during a rising-ramp period and low reset voltage.

• KIEAE Journal
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• v.7 no.4
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• pp.31-38
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• 2007

Streetscape plays on important role in urban cities. Characteristics of streets is basically defined by the building facade, signs, plants and paving during the daytime. However at night, street receives a new appearance due to the shop light from the buildings, exterior lightings, signboards and street light, and it creates most of the image of the streets. This study aims to analyze the luminous environment and its subjective image of two different pedestrian's commercial streets. Insa-dong street and Myungdong street were chosen for the study. Horizontal illuminance and luminance on building surface, advertisement billboards and pedestrian road were measured. Thirty students were asked to rate the five scaled questionnaire on their subjective images of the streets. Statistical analysis including profile, correlation and T-test are conducted and some findings are discussed

• Journal of Information Display
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• v.2 no.4
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• pp.46-51
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• 2001

Using ray-optics code incorporated with three-dimensional PDP cell simulation, we have analysed the energy flow in the PDP cell from the electric power input to the visible light output. Also, the visible light output profile and viewing angle distribution were obtained. We applied our code to the analysis of the barrier rib height effect on the visible light luminance and efficiency of the sustaining discharge. Although cells with higher barrier rib generate more VUV photons, less ratio of visible photons are emitted toward front panel due to the shadow effect. Thus, there exists optimal barrier rib height giving the highest visible luminance and efficiency. This kind of code can be a powerful tool in designing cell geometry.

• 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.

• KIEAE Journal
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• v.6 no.4
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• pp.25-32
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• 2006

Mock-up model can be applied to measure accurate performance data but difficult to apply the variables in experiment. There can be a slight experiment errors in Scale model, but various parameters can be applied for a objective experiment. This paper aims to compare the daylighting performance in 1, 1/5, 1/10 scale model of offices and analyze the experiment errors to certificate the influence of model experiment. To analyse daylighting performance, a comparison of a Mock-up model, sized $12.0m(w){\times}7.2m(l){\times}3.7m(h)$, designed for experimentation of daylighting systems and its 1:5, 1:10 scale model. It has an identical configuration of reference room and the test room. For the test room, the lightshelf system was designed as Micro-4 reflective material. To assess work plane illuminance and light factor, photometric sensors of each room were installed at work-plane(6 points) and exterior horizontal illuminance (1 point). And luminance of window, rare of the room was measured under clear sky. It is to be monitored by Agilent data logger, photometric sensor Li-cor and the Radiant Imaging ProMetric 1400. Comparisons with a light factor, increase-decrease ratio and luminance are discussed.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.30 no.4
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• pp.241-245
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• 2017

This paper proposes a private display that can adjust viewing angles by using an electric-field-driven (EFD) LC Lens. The EFD LC Lens design and simulation were analyzed by using the Extended Jones Matrix Method. The conventional method for attaching a private film to the display was difficult. In order to solve this problem, in this study, by using the EFD LC Lens, we devised a method that can view images more conveniently. We analyzed the luminance and illumination of the optical viewing distance by using the Extended Jones Matrix Method. We also measured the intensity of the viewing angles. The simulation attached the EFD LC Lens to the 14" Full HD RGB stripe wide panel. We calculated the relative luminance distribution and the luminance distribution on the viewing angle of the image at the optimum viewing distance of 60 cm, using the EFD LC Lens and the lenticular lens. The proposed method could be used to design private displays that can adjust the viewing angle of the EFD LC Lens.

• ETRI Journal
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• v.42 no.2
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• pp.258-271
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• 2020

A correlation exists between luminance samples and chrominance samples of a color image. It is beneficial to exploit such interchannel redundancy for color image compression. We propose an algorithm that predicts chrominance components Cb and Cr from the luminance component Y. The prediction model is trained by supervised learning with Laplacian-regularized least squares to minimize the total prediction error. Kernel principal component analysis mapping, which reduces computational complexity, is implemented on the same point set at both the encoder and decoder to ensure that predictions are identical at both the ends without signaling extra location information. In addition, chrominance subsampling and entropy coding for model parameters are adopted to further reduce the bit rate. Finally, luminance information and model parameters are stored for image reconstruction. Experimental results show the performance superiority of the proposed algorithm over its predecessor and JPEG, and even over JPEG-XR. The compensation version with the chrominance difference of the proposed algorithm performs close to and even better than JPEG2000 in some cases.