• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 2009.10a
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• pp.169-172
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• 2009

Daylight responsive dimming system, which is one of the method for utilizing available daylight. continuously adjusts lighting output with an algorithm of the correlation of photosensor signal and workplane illuminance levels. This system must be related with shading systems which are to control penetrating daylight. The purpose of this research is to analyze illuminance distributions by artificial lighting in different shading systems. Lighting power is changed by 5 levels in nighttime for comparing correlation between illuminance and lighting power in different shading systems.

• Journal of the Korean Solar Energy Society
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• v.34 no.5
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• pp.1-9
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• 2014

Daylight is very useful to control the indoor environment, and can save energy in buildings. So it is necessary to evaluate the daylighting performance of buildings. We proposed a simplified equation that can be used in the early stages of design. And we verified the equation by using the measured illuminance data from the 1/5 scale model. We compared the calculated indoor illuminances and measured illuminance including Daylight Factors of scale model in order to verify the applicability of the simplified equation, and proved the analyzed values are acceptable. When we have a target value of the Daylight Factor, we just have to determine the window area, transmittance of the glazing system, and indoor surface reflectance, then can achieve it with this simplified equation.

• 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.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 2002.11a
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• pp.87-90
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• 2002

Daylight responsive dimming system, which is always able to automatically maintain the target illuminance, is a energy strategic system. It is importance note that the photosensor depends how to be precisely indicated workplane illuminance at any location of indoor. Therefore, the purpose of this paper is to find out the optimum location and spatial characteristics of photosensor by considering the correlation for the correct calibration of workplane illuminance and photosensor signal.

• Architectural research
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• v.7 no.2
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• pp.47-54
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• 2005

A photoelectric dimming control system for a small private office space with a double skin envelope system was analyzed for the purpose of examining optimum control performances under a variety of daylight conditions. Computer simulations were performed for the three different photosensor types positioned at the center of ceiling in the space. They were applied in both a south and north-facing room. Daylight conditions were a fixed horizontal venetian blind on an external envelope and a retractable shading device on an internal envelope under a clear, intermediate and overcast sky at different times of a day and year. Partially-shielded photosensors provided good control performances providing the required electric light output under clear and intermediate sky conditions. Unshielded photosensors failed to provide necessary illuminance levels producing less electric output and fully-shielded photosensors generally provided excessive light output. Reasonable electric lighting energy savings were achieved except under overcast sky conditions where the control system did not contribute to energy savings due to the less daylight through envelopes. The retractable shading device covering 50% of the internal envelope reduced energy savings up to 19.62%, but the workplane illuminance levels were maintained within recommended ranges. The coefficients of determination between workplane illuminance and photosensor illuminance due to daylight ranged from 0.74 to 0.98. Partially-shielded conditions provided best correlations and the north-facing room yielded stronger correlation than the south-facing room.

• Journal of the Korean Institute of Educational Facilities
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• v.9 no.5
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• pp.13-21
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• 2002

Daylighting in educational environment is very important as it has an effect on students' performance as well as in their visual health. It is regarded as a good energy conservation method in saving energy used for lighting. This study conducted initial daylight measurements to analyze luminous environment in classrooms of Korean elementary school. The results indicated that the typical classroom had a reasonable level of daylight. However, it also found that the classroom had some problems of the uniformity of illuminance and the contrast of brightness of surfaces in the classroom. It is argued that daylighting design for school classroom should consider these aspects to make daylit classrooms ideal so as to provide comfortable visual environment.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 2008.10a
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• pp.13-16
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• 2008

The aim of this study is to analyze the daylight performance at Changdeokgung Nakseonjae that is the representative and most well preserved Korean royal palace. As a result of measuring illuminance and luminance, direct sunlight is cut off by the eaves and reflective light from the court comes in the inside of the upper floor. As the layer of window is increased, daylight is decreased and the illuminance distribution is more stable because of decreasing of illuminance change. This study would be used as preliminary data for applying characteristics of lighting environment of Korean royal palace to modern architecture.

• Architectural research
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• v.2 no.1
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• pp.41-46
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• 2000

The sawtooth skylight is an excellent daylighting concept for the uniform interior illuminance over large working areas. In computer simulation, it is difficult for an architect to get accurate daylight illuminances for the spaces where sawtooth apertures are applied. In this study, daylight prediction algorithms for sawtooth apertures are developed. The flux transfer method is applied for this study to predict daylight illuminances. The simplified equations from this study can be used effectively for preliminary prediction of daylight in sawtooth spaces.

• Journal of the Korean Solar Energy Society
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• v.24 no.4
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• pp.35-43
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• 2004

Illuminance and luminous levels in a small office space due to daylight were calculated to analyze the impact of daylight on contrast and lighting energy savings. Computer simulations were performed for four blind conditions under a clear sky condition. The blind conditions significantly impacted the illuminance an4 luminance level. Visual performance scores were calculated according to the transfer function that uses absolute contrast between target and background surface. The blind condition that had 45 tilted angle toward ground provided good contrast and performance scores. Using a control algorithm of an automated daylight dimming control system lighting energy sayings were predicted. For all blind conditions minimum lighting energy was consumed.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 1991.10a
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• pp.23-27
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• 1991

The Monte Carlo Simulation has been used widely in physics for computing flux transfer, pricipally in applications where direct solution of analytical equations is very difficult. But it seldom has been applied in determining interior lighting. This article summarizes the Method, and deals with numerical results of illuminance distribution. This Method considers daylight as well as artificial light sources.