• 한국태양에너지학회:학술대회논문집
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• 2009.04a
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• pp.83-90
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• 2009

As a series of 'Performance Assessment of Building Envelopes I: Double Skin Facade', three types (interior, exterior, mixed (int.&ext.)) of lightshelves and RetroLux were examined in terms of $CO_2$ emissions. It is shown that the exterior lightshelf could achieve the most energy savings (9.6-38.7%) in general office buildings due to blocking solar radiation before entering the indoor space. However, the interior lightshelf is the worst (1.4-5.2%) among three of them. The RetroLux has two components: (1) sun-reflector (first louver component), (2) light shelf for improving daylight induction (second louver component). Due to these two components, solar radiation from windows is filtered depending on seasonal variation (solar altitude). Therefore, the RetroLux can reduce 18.0-27.9% of annual energy consumption (both cooling and heating), and $552-3,290Won/m^2{\cdot}yr$ of operation cost is saved.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.29 no.5
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• pp.229-237
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• 2019

For maintaining high visibility of lane, the high refractive index glass beads with excellent retro-reflectivity are usually applied on the road marking paint. The retro-reflectivity standard of general road marking is different in each country; it is defined as $240mcd/m^2{\cdot}lux$ based on white light in Korea and $250{\sim}300mcd/m^2{\cdot}lux$ in developed countries. In this paper, the recent trends on the manufacturing technology of glass beads suitable for autonomous driving age as well as the road marking regulations has been reviewed. Also, in preparation for the commercialization of autonomous vehicles in the future, the necessity of raising the standard value and improving the glass bead properties were proposed.