• Journal of the Architectural Institute of Korea Structure & Construction
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• v.34 no.12
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• pp.65-72
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• 2018

The purpose of this study is to predict vertical illuminance accurately at the design stage of a building without the help of simulation tools. Comparing two well-known vertical illuminance prediction algorithms with measured values, it is verified that the Igawa model is more consistent with the measured values than the Perez model. Using the DIVA program, we simulated the vertical illuminance at 30-degree intervals from south to north, compared with the vertical illuminance calculated with the Igawa model. The result of calculation values were verified from 120 degrees east to 120 degrees west. The vertical illuminance values with each of three shade devices were calculated using the Igawa model, and compared with the vertical illuminance simulated by DIVA program. As a result, all the errors when installing horizontal / vertical / grid shade divices were included in the error standard specified by ASHRAE.

• Journal of the Korean Solar Energy Society
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• v.34 no.1
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• pp.19-27
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• 2014

Exterior vertical illuminance is an important factor for lighting control. But, there are not many researches about the exterior illuminance on a vertical surface. In this study, we predicted the exterior illuminance on a vertical surface using vertical luminous efficacy. First, we calculated the vertical luminous efficacy according to the sky clearness category. And we performed the statistical analysis of the measured and the calculated illuminance with luminous efficacy. The MBE and RMSE of the predicted exterior illuminance were-1.2% and 15.5%, respectively. Second, the annual illuminance on a vertical surface calculated with the luminous efficacy and the short-term measured solar irradiance was suggested in this study.

• 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.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.24 no.5
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• pp.433-442
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• 2012

The influence of outdoor sky conditions on photosensor signals were examined to determine an appropriate index that is effectively used for optimum illuminance fluctuation when a daylight dimming system is used for a small office. Field measurements were conducted under various sky conditions. Results indicate that the outdoor global and vertical illuminance fluctuated within narrow ranges under clear and overcast sky conditions. The fluctuation of sky ratio under partly-cloudy sky caused wide ranges of illumnance fluctuation. A partially-shielded photosensor at backwall produced 56% of light output from fixtures controlled by a photosensor at ceiling. This implies that the photosensor at backwall does not always guarantee target illuminance due to the less output. The fluctuation of light output from fixtures were insignificant under clear and overcast sky. The fluctuation range of photosensor illuminance under partly-cloudy sky caused wide fluctuation ranges of light output. Regression result implies that the outdoor vertical illuminance was recommended for an effective index that is used for control of light output.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 1999.11a
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• pp.175-180
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• 1999

This paper presents the effective design of the change of average illuminance and the arrangement of lamps by changing the form of working area and adjusting the distance between the wall and light. This study is intended to simplify the complex calculation of illuminance through the development of application program. It's plan to study application programs that can attain the value of advanced uniformly-distributed illuminance and average illuminance by changing the distance between the horizontal/vertical wall and lamp and between the horizontal/vertical lamp and lamp.

• Journal of the Korean Solar Energy Society
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• v.32 no.3
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• pp.50-58
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• 2012

The objective of this study is to evaluate the lighting dimming rates with various parameters of the building skin in a small office. We compared to simulated workplane illuminance and measured workplane illuminance for the base model. After that, the five veriables(the presence of vertical wall in double skin facade, the presence of windowsill, window to wall ratio(WWR), window visible transmittance, the width of double skin facade) were applied to base model, and we analyzed the simulated lighting energy saving rates. The results are listed as below. The simulated workplane illuminance results are similar to the measurement. Simulated illuminance was smaller than measured illuminance by 16.5%(60 lx). In accordance with applicable building skin parameters, lighting energy saving rate results are summarized as follows. Lighting energy saving rate of case1(windowsill height 0.7m) is higher than that of base case(windowsill and vertical wall) by 7.3% and the lighting energy saving rate of case2(no vertical wall) is higher than that of base case by 7.6% and the lighting energy saving rate of case3(no windowsill and vertical wall) is higher than that of base case by 12.4%. The lighting energy saving rate is increased by 2.3%, when window visible transmittance is increased from 70% to 86%. The lighting energy saving rate is increased by 4.6%, when we changed the WWR 70% to 90%. lighting energy savings rate is increased by 6.5%, when the width of double skin facade is reduced from 1m to 0.3m.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.18 no.1
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• pp.1-8
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• 2004

Nowadays the soccer becomes one of the best spot lighting sports in the world Especially the 2002 Korea-Japan World Cup was deeply impressed on all the korean. One goal of illuminating engineering should be the design of lighting system that can provide consistently high task visibility regardless of where a task might be located within a working space. The television broadcasting on the soccer has been an important role in the media. The standard of FIFA(The Federation Internationale do Football Association) requires recommended illuminance levels for artificial lighting for a player, an audience, TV broadcasting, as well as everybody in the stadium. This paper has proposed an algerian to select the suboptimal lighting tower position for watching and TV broadcasting a soccer game within a pleasant environment and an optimum illuminance distribution. The position using the software Philip's Calculux was chosen based an the calculations of a horizontal illuminance, vertical illuminance, uniformity, glare, and so on by changing lighting tower positions.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.22 no.11
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• pp.788-797
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• 2010

This study examines the influence of fluctuating daylight illuminance on daylight dimming control systems. Field measurements were performed for a full-scale mocked-up model under various daylight conditions in winter. Fluctuating ranges for a partially-shielded photosensor were great when the variation of sky ratio was great. When solar altitude was lower the illuminance and fluctuating range of illuminance were great due to the influence of direct components of daylight and the interrefelction between surfaces in rear area of space. It implies that daylight dimming system would not function effectively, unless the desktop illuminance by daylight is enough. Fluctuation ranges of photosensor illuminance were lower than 50 lx under clear sky conditions, but they were greater than 100 lx under partly-cloudy sky conditions. It means that the fluctuation range of electric light output of lighting fixture would greater under the partly-cloudy conditions and cause potential visual annoyance to occupants. Outdoor vertical illuminance reaching the windows would be an effective factor that can be used to predict the fluctuation of photosensor signals for effective controls of daylight dimming system.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.23 no.1
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• pp.61-72
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• 2011

The influences of luminous environment on visual responses and fatigue sensation in art galleries were examined in this study. Field measurements and survey were performed in three galleries under various illuminance and luminous conditions. Result implies that vertical illuminance on art paintings needed to be somewhere between 200 lx and 300 lx to avoid visual discomfort. The vertical illuminance difference between consecutive paintings should not exceed 100 lx to keep visually comfortable environment. Visual comfort sensations were related to glare, visual stimulus, reflection from paintings, illuminance variation, and the sensation that subjects can clearly see the paintings. The sensation of fatigue was significantly influenced by the changes of luminous element that caused visual stimulus and discomfort. The sensation of eye fatigue among physical fatigue was primarily influenced by the glare, visual stimulus and comfort. The psychological fatigue was also influenced by eye fatigue, visual comfort, brightness and satisfaction with color of light.

• KIEAE Journal
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• v.10 no.6
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• pp.41-46
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• 2010

This study is to validate the K University daylight measurement system according to the CIE guide of recommended practice of daylight measurement. In this study global irradiance, illuminance, direct normal illuminance, diffuse irradiance, illuminance and vertical illuminances(North, West, South, East) were measured and compared in accordance with the CIE quality control test. Field monitoring was conducted from 1st August to 15th August 2010. Results for the CIE tests 1 to 4 showed an accuracy of 100%. This indicates that the K University daylight measurement system is reliable and the measurement data would be useful for further daylight researches.