• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.25 no.4
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• pp.1-6
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• 2011

The elder population with 65 years old or more in Korea has been entered into an aging society as 9.1[%] in 2005 to 14.3[%] in 2018. The elder population in 2026 will be expected to 20.8[%] with the rapid aging society. In this study, there has been conducted a study on development of headlamp for elder friendly vehicle in order to ffrom two different groups, one group for elder with over 65 ages, the other group for compared ages(20 ages, 30~50 ages). Glare test and forward visibility test were performed on wet and dry road conditions. As the result of these tests, it showed to prefer headlamp installed partially yellow coated bulb, which gives warm feeling on dry road condition. Forward visibility of headlamp which developed to fit on wet road condition is similar to existing HID headlamp. Glare was evaluated less than halogen and HID headlamp. However, it need to more improve glare and forward visibility performance of headlamp for old drivers.

• Journal of the Korean Solar Energy Society
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• v.32 no.2
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• pp.74-86
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• 2012

For the improvement of environmental comfort in the buildings with the blind control, the objective of this study is to prevent the direct glare caused by the daylight inlet. During the process of solar profile prediction, time are significant factors that may cause error and glare during the blind control. This research proposes and evaluates the correction and control method to minimize prediction error. For the local areas with different longitude and local standard meridian, error occurred in the process of the time conversion from local standard time to apparent solar time. In order to correct error in time conversion, apparent solar time should be recalculated after adjusting the day of year and the equation of time. To solve the problems by the potential time errors, control method is suggested to divide the control sections using the calibrated fitting-curve and this method is verified through simulations. The proposed correction and control method, which considered potential time errors by loop lop leap years, could solve the problems about direct glare caused by daylight inlet on the work-plane according to the prediction errors of solar profile. And also these methods could maximize daylight inlet and solar heat gain, because the blocked area on windows could be minimized.

• KIEAE Journal
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• v.12 no.6
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• pp.107-112
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• 2012

The purpose of this study is to determine the optimum slat angle of the venetian blind which was applied at an outer skin of a curtain-wall system. The evaluation of the blind slat angle was performed in terms of the comfortable visual environment and decreased energy consumption. The office building prototype was considered for the analysis and simulation variables include application of blind, blind slat angle and dimming control of lighting. The annual energy consumption and incidence rate of discomfort glare were analyzed using EnergyPlus which is developed by the U. S. Department of Energy for the detailed building energy simulation. As a result, it turns out that when the blind (reflectance: 0.5) was installed, the annual energy consumption was greater than that of the base model. However, when the dimming control was applied, the maximum energy saving of 16.3% could be achieved at a slat angle of $0^{\circ}$. In addition, in case of the base model, the incidence rate of discomfort glare was 84%, while the case of the blind with the slat angle of $0^{\circ}$ showed that the incidence rate of discomfort glare was 42.4%. Consequently, the results showed that the slat angle of $55^{\circ}$ with dimming control was the optimum strategy for the comfortable visual environment and decreased energy consumption.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.27 no.12
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• pp.54-62
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• 2013

In this study, a mock powder room was installed with variable LED lighting environments in order to conduct the experiments. The experimental conditions include luminaire type, illuminance ratio, vertical illuminance and color temperatures. The evaluation methods used were the Semantic Differential Method and a subjective evaluation on activities through observation. The SD evaluation result factor analysis categorizes ideas into three factors: brightness, emotion, and glare. The vertical bracket or the combined luminaire (luminous panel+ Vertical bracket) has better brightness than luminous panel. A vertical illuminance of 500lx is not significantly difference as compared to 600lx, allowing 500lx to be considered standard. The emotional atmosphere is evaluated as being better at lower color temperature. The luminous panel is the best for reducing glare while the vertical bracket is the worst. The best conditions differ according to the illuminance ratio of the luminous panel and vertical bracket. In the subjective evaluation (satisfaction with lighting environment, suitability to activity) the combined luminaire and 4000K received the best evaluation.

• Journal of Korean Tunnelling and Underground Space Association
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• v.14 no.1
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• pp.93-105
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• 2012

The basic study was preceded for reducing maintenance and power cost of lighting fixture applying daylighting because most of the tunnel lighting depend on the artificial lighting. This study aims to evaluate the daylighting performance of daylighting performance of bar-type mirror reflector system in tunnel. Illuminance and luminance was measured. As a result of horizontal illuminance measurements, it was satisfied in tunnel recommended illuminance (KSA 3703) that total average was 1,170 lx increased 6.5 times more than this system was not used. Also, as a result of evaluating driver's glare on the opposite lane, glare did not occur and the luminance ratio was 3.01 which satisfies the luminance ratio standard 10.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2002.10a
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• pp.177-184
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• 2002

The concrete median barriers are the most popular safety appurtenances that can be installed on narrow medians and are effective in keeping uncontrolled vehicles from crossing into opposing lanes of traffic. It is necessary to install and maintain median barriers because it is very difficult to reserve enough room required for medians in KOREA. And concrete median barriers are accepted as the actual alternatives for median barriers, mostly because they require almost no maintenance even after serious collisions. Typical concrete median barriers are 810mm high and have 596mm high glare screens on top of them. But we have experienced a number of “climb” and “roll-over” accidents of heavy vehicles until now, and most of all, there have been some serious accidents caused by the part of broken glare screens. We have performed many computer simulations for the evaluation of the crashworthiness of concrete median barriers, and through the simulations we have tried to find a proper type of concrete median barrier.

• Korean Journal of Digital Imaging in Medicine
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• v.10 no.1
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• pp.21-28
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• 2008

Diagnostic display monitor QA according to AAPM TG18 is usually performed by PACS administrator, product manager and reading doctor, and for acceptance testing and periodic quality control evaluation, a combination of visual and quantitative tests can be used, as outlined in sections 5 and 6 of 'assessment of display performance for medical imaging systems'. Although many display tests can be performed visually, a more objective and quantitative evaluation of display performance requires special test tools. The required instruments vary in their complexity and cost, depending on the context of the evaluation(research, acceptance testing, or quality control) and how thorough the evaluation needs to be. Objective and reliable assessment of many display characteristics can be performed with relatively inexpensive equipment, So, we made 'AAPM TG18 guiding instrument' to ues variable purpose of the evaluation of 'geometrical distortions(quantitative"', 'veiling glare(visual)' and 'sensor calibration'. The spatial measurements for the quantitative evaluation of geometric distortions, and the measurement of the veling-glare ring response function which provides information regarding the spatial extent of the luminance spread, can be performed using the TG18 guiding instrument can be used to sensor calibration to standardize the basic rate of 0% luminance when periodic calibration.

• KIEAE Journal
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• v.15 no.3
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• pp.49-56
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• 2015

Purpose: Due to recent increase on energy consumption for light in building, many studies to mitigate this issue have been conducted. Various researches have been carried out to suggest light shelf as one of the solutions, but researches for its reflectivity is very few. In fact, existing research on light shelf shows that utilizing more than 90% of high-illumination materials causes imbalance of glare and illuminance. Method: Therefore this research aimed to evaluate the performance of light shelves depending on reflectivity and to identify proper solution through test-bed. Result: The results are following: 1) Increased reflectivity generally contributed to increase of indoor illuminance but degrade uniformity factor related with indoor comfort of light environment. 2) The $0^{\circ}fixed$ light shelf with 75% of reflectivity and width of 300mm and 40mm appeared to consume more energy than other shelves. Therefore, it is analyzed as unsuitable. 3) This research was conducted by calculating appropriate angle of light shelf around winter and summer solstices and vernal/autumnal equinox. Based on this, performance evaluation was undertaken depending on reflectivity of movable light shelf, which is activated by external sources and can be applied with lower reflectivity than fixed shelf. However, one exception was a movable shelf with width of 600mm that increased light energy consumption when 75% of reflectivity was applied. 4) Performance evaluation of fixed and movable light shelf showed that the shelf with 80% of reflectivity came up with suitable results, but 75% of reflectivity may be applied depending on the width and angle of the shelf. This research is meaningful in that estimation of appropriate reflectivity of light shelf can resolve the glare problem and improve light environment, and further research would be desirable under more diverse conditions to identify proper solution.

• Journal of the Korea institute for structural maintenance and inspection
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• v.25 no.1
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• pp.93-102
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• 2021

This paper describes the process of developing a concrete median barrier of SB4 grade with anti-glare function. The development section has a height and width of 1,270mm and 560mm, respectively. A wire mesh is placed in the center of the cross section to improve the protection performance. Collision analysis predicted that this section satisfies the strength and occupant protection performance, and that no damage to the barrier occurs. In the actual collision test, it was confirmed that this section satisfies the strength and occupant protection performance. However, damage was observed on two concrete barrier when the truck crashed. In order to improve the accuracy of the collision analysis of the concrete barrier in the future, it is considered that a study on the model development and continuous collision analysis method for domestic commercial vehicles should be carried out.

• Journal of the Korean Solar Energy Society
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• v.31 no.6
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• pp.111-124
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• 2011

The objective of this study is to develop the blind control strategy and method which reduce negative effect of incoming daylight on visual comfort of occupants, minimize psychological anxieties caused by frequent motions of a blind, and maximize positive effect of incoming daylight by opening/closing of a blind. In previous researches on blind controls, major problem is that the time interval and amount of blind movement do not meet the control objective at the inflected zone of solar profile curve. To overcome these limitations revealed in theprevious researches, following tasks were performed in this study. i)To establish the control objective to accomplish the goal of this study. ii)To develop the control methods and algorithms which prevent glare on the work-plane at any time and which control the time interval and amount of blind movement to follow the control objective at various solar profile angle curves. This study proposed the control strategy and method that define the base control section implying the inflection point within the control objective zone and subsequently, divide the control sections for the residual time zones. The proposed strategy and method are found to increase the incoming daylight and solar irradiation by 0 to 15 %.