• Journal of the Korean Solar Energy Society
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• v.31 no.6
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• pp.86-94
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• 2011

For accurate dayligh tsimulation, accurate exterior illuminance is necessary. But, Korea Meteorological Agency provides only the solar irradiance data. Thus, there is a need for the research on luminous efficacy. In this study, global horizontal irradiance, diffuse horizontal irradiance, global horizontal illuminance, and diffuse horizontal illuminance were measured to calculate the luminous efficacy in SEOUL. And, we evaluated the applicability of the Perez's model by comparing the measured data and calculated data. As a result, measured global luminous efficacy is 126(110~129)lm/W and diffuse luminous efficacy is 127(115~133)lm/W in Seoul. Perez's model was relatively accurate with 5% difference in the diffuse luminous efficacy. But, it can be predicted about 15% lower in the global luminous efficacy.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.12
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• pp.685-696
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• 2017

In the spatial image composition of a cathedral, light is the most important element of changing the mind through vision. The religious meaning of light and its impact on human sensibility are believed to be very large. Therefore, in this study, 'Illuminance' is the most important research subject of a cathedral's worship space lighting plan elements. Illuminance is expressed by giving the clarity and form of space through a subtle spatial composition difference. The role of illuminance is essential for confirming the existence of space, and lighting controls the spatial atmosphere at an appropriate level. The standard and range of illuminance are set through the synthesis and analysis of related standards. Based on this, a related case study was conducted on cathedrals built in the Gangnam area of Seoul in the 1980s. The lighting-related factors were analyzed and the illuminance of the liturgical space and worship area were measured. The appropriate level of applicability was confirmed by comparison analysis. A plan for the illuminance application levels and elements applied in the cathedral lighting design is proposed.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.15 no.1
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• pp.425-429
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• 2014

The visibility range is defined from where one can see. And it can be changed by illuminance, the character size, and eyesight and so on. In this paper the visibility range of 120 students is measured for 4 character sizes and 3 illuminations in a classroom. In order to forecast the visibility range of unmeasured data, using least square approximation theory, functions whose independent variable is illuminance and whose dependent variable is the visibility range is proposed. Because the visibility range is invariant according to illuminance, common logarithmic functions for 4 character sizes are used. The small difference between the postulated functions and the measured data verifies the accuracy of the functions.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.29 no.9
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• pp.1-9
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• 2015

The aim of this study is to deduce color temperature and illuminance by conducting the preference & affective evaluation consequent on illuminance change of ambient light in case of the lighting method of ambient light mixed with task light in time of reading which is visual work action among the action in learning space. As a result of the prior survey on preferred lighting method in time of the act of reading targeting 20 experts before doing evaluation, the method of lighting mixed with ambient light and task light was found to be the highest. Such a result is analyzed to be attributable to the fact that the less the difference in illuminance of nearby space and work surface because of the mixed method of lighting, the less the glare, which makes a reader feels easy and concentrate on reading. On the basis of descriptive statistics of evaluation results and impact analysis by category, this study recommends the application of combinations of ambient light illuminance ranging from 40lx to 100lx with color temperature of 5500~6000K in case of the method of lighting mixed with general light and task light.

• Korean Journal of Environment and Ecology
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• v.29 no.3
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• pp.441-453
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• 2015

In this paper, according to the illuminance at night with artificial lighting in downtown Seoul, trees flowering and leaf growth rate was performed as a case study to examine whether there is a difference. The illuminance was measured at 78 points on a total of 26 points, the range of illuminance were divided into three groups considering land use, Group A (plots 1-7) were 4.90 ~ 112.50 lx, Group B (plots 8 to 18) were 0.45 ~ 42.40 lx, group C (plots 19 to 26) were 0.28 ~ 22.10 lx. According to the One-way ANOVA on illuminance difference, the survey groups were classified into three groups. To survey the ratio of the flowering Prunus yedoensis and Rhododendron spp. and to survey the ratio of leaf growth Zelkova serrata, Ginkgo biloba, and Acer palmatum each 30 individuals were investigated. Rhododendron spp. to study the ratio of the flowering and Acer palmatum to study the ratio of leaf growth were determined to be useful as indicator woody species according to the correlation. The higher illuminance of night lighting is, the faster flowering and leaf growth of trees will be by correlation between the mean illuminance of each group and the flowering and leaf growth of trees. In the future, should be made a more detailed study of how much affect to the trees with some impact on the level of light pollution at night lighting.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.27 no.12
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• pp.16-27
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• 2013

This study describes the difference of lighting directing techniques of between asian and westerner in the residential space, and presents the LED lighting environment according to the residents' behaviors. This study was conducted with Koreans, European and North Americans, and the space range was limited to the living room where the various activities occur. The data of the desired LED lighting environment is drawn through lighting technique, illumination color temperature and illuminance variation of LED in living room, and the detailed study results are as follows ; First, the lighting in living space should be made with considering the various behaviors because the expected level according to consideration or not of behavior makes much difference. Second, the comfortably feeling LED lighting environments that are lighting technique, illumination color temperature and illuminance variation, are different between Koreans and North Americans, but Koreans and European feel comfortable under the similar LED lighting environments. Third, the data for the comfortable LED lighting environments is established according to the various residents' behaviors, which are watching TV, reading, studying, relaxing, chatting, entertaining guests. And then, the established LED lighting environments are analyzed with characteristic of behavior and classified according to lighting technique, illumination color temperature and illuminance variation for understanding their characteristic Few studies have been conducted to find out difference of the comfortably feeling LED lighting environment between asians and westerners. Therefore, in this study, it has a great significance to present the difference of the LED lighting environments that asians and westerners feel comfortable in living space, and to draw the characteristic of the expected lighting environment according to residents' behaviors.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.11 no.2
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• pp.145-152
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• 2011

Stage-broadcasting Fresnel and Plano Convex Lighting fixture were fabricated. Compare illumination simulation and measured values for Fresnel and Plano Convex fixture. After made Lighting install studio motor system construction. In studio Daejeon Health Sciences College we measured illuminance and simulation in order to compare Fresnel and Plano Convex Lighting. And we study how much different illuminance between Fresnel and Plano Convex Lighting. In the result of comparison of simulation Fresnel and Plano Convex Lighting fixture are measures of difference value 39.7~250.6Lux and comparison of actually Fresnel and Plano Convex Lighting fixture are measure of difference value 92.84~157.35Lux.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 1998.11a
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• pp.151-155
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• 1998

In this paper it is examined the validity of luminance-to-illuminance conversion factor in the roadway lighting design. Luminance and illuminance distribution patterns were measured to yield the calculated conversion factor on the newly-constructed highway, and this value was compared to the conversion factor commonly used. We found that some discrepancy might exist between them due to difference in the values between the luminance yield factor and the coefficient of utilization. Therefore this fact must be fully understood in the roadway lighting design process.

• 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.

• Journal of the Korean Magnetics Society
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• v.26 no.5
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• pp.168-172
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• 2016

The purpose of the optimal environment of the MRI room to measured luminance and illuminance of the MRI room and the monitor. University Hospital (n = 6) of the MRI (n = 10) in the luminance and illuminance Light Probe Xi Unfors (Unfors Instruments AB, Billdal, Sweden) was measured by using the. Black luminance level and white level of illuminance is repeated three times in the middle of the side of the monitor to obtain the mean and standard deviation using a t-test statistical processing was of significance test. Monitor luminance and black level in the average $1.78cd/m^2$, the standard deviation was $0.85cd/m^2$, white level average of $43.58cd/m^2$, the standard deviation of $13.19cd/m^2$. Illuminance of MRI room was the lowest value measured in accordance with the 30.5 lux, the maximum value is 601.3 lux, mean was measured by a variety of 177.86 lux. Luminance and illuminance of the MRI room and monitor is found to have statistically significant difference (p < .05). In conclusion, refer to the recommended standard of MRI and room monitor luminance and illuminance and to create an optimal environment.