• KIEAE Journal
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• v.17 no.2
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• pp.29-34
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• 2017

Purpose: Recently, significant heat loss through the window takes place in buildings. Nevertheless, there exists little literature concerning the exterior horizontal shading devices and the design criteria are not clearly settled yet. Applying the exterior horizontal shading devices is more efficient as compared to the interior shading devices in that solar radiation can be directly blocked before passing through the window or the envelope. The purpose of this study is to reduce the internal load by designing the exterior horizontal shading devices and verify the degree of reduction in energy consumption. Method: This study aims to reduce energy consumption in cooling and heating through proposing proper length and shape of the exterior horizontal shading devices in public buildings. In the process, actual energy data and the Design Builder simulation program are utilized. In addition, economic aspect is considered to figure out the optimal length of the exterior horizontal shading devices that maximizes efficiency. Result: As a result, the proper length and shape of the exterior horizontal shading devices are provided as follows: 1) Energy consumption in cooling and heating is minimized when the exterior horizontal shading devices are designed as 0.5m*2. 2) Electricity bill is the lowest when the exterior horizontal shading devices are designed as 3.3m*2. The gap between maximum and minimum electricity bill is about 7.8~14%.

• Journal of the Korean Institute of Educational Facilities
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• v.15 no.2
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• pp.4-15
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• 2008

The purpose of this study was to evaluate the characteristics of daylighting environment in classroom of an school building due to the external shading devices such as fixed louvers, light shelves and exterior venetian blinds. In this study, we have made a field research with regard to the facade design in classroom of an school building. And we have made a classification of external shading devices considering the design parameters. Finally, through RADIANCE simulation, we have calculated the spatial distribution of illuminance, uniformity ratio of illuminance and daylight factors. The results of this study will provide the building designer with the basic daylighting performance data at early design stages.

• Journal of the Korean Solar Energy Society
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• v.33 no.2
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• pp.28-34
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• 2013

It is essential to reduce building energy consumption in office building because government enact policy which encourages building energy certification from 2013. Office building has high cooling energy demand due to large glazed area of facade in these days. Shading devices can be an alternative of reducing high cooling energy demand. So, this study simulated a variety of exterior venetian blinds to know how much building energy be affected by orientation and reflectance of slat. The results of this study are based on Seoul weather data. The following is a summary of this study. 1) As a slat of venetian blinds has the lower reflectance, the more building energy reduced. Reflectance is usually affected by color and material of slat. In case reflectance is 0.2 reduce 4% of building energy than reflectance is 0.8. 2) Horizontal exterior venetian blinds are more effective than vertical exterior venetian blinds in all of orientation. Horizontal shape is average 16% more effective in shading effect than vertical shape. 3) In this case study, the most effective shading device is low reflectance horizontal exterior venetian blinds that result about 18% building energy reduction than no shade model. The results of this research can be used to plan shading devices for energy conservative office building.

• KIEAE Journal
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• v.14 no.5
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• pp.67-73
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• 2014

This study aims at examining kinetic efficient shading systems and their implementation methods. These days, the importance of the shading devices are getting more significant due to the energy problem. Cordially, suitable shade designs are required as an important element for the exterior envelope of the building. This study employs the optimal shading design as an efficient shading method with the kinetic system that can be converted actively by the altitude of the sun. The proposed kinetic shading system works not only as a lightshelf in case the altitude of the sun is high but also as a vertical louver when the sun is getting lower in order to block the direct sunlight. This study has analyzed the thermal performance and shading coefficient of the kinetic shading system in comparison to existing fixed shading devices using the Ecotect. The results, in sum, conclude that the suggested kinetic shading system could decrease direct sunlights 26.2% more than the existing shading methods.

• Journal of the Korean Solar Energy Society
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• v.29 no.3
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• pp.28-36
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• 2009

The majority of fixed shading devices are installed in the exterior of a building in order to dissipate the heat absorbing from the sun and to prevent the direct sunlight. In designing external shading devices for windows, many requirements must be considered simultaneously; solar geometry, optimum energy performance, multi-purpose usage and design factors etc.. In order Lo satisfy these requirements, we suggests the folding shading device and its optimum design methodology. Also we analyzed the thermal performance using the IES_VE program according to various operating modes and compared with existing shading devices. The results show that proposed device reduce about $1.90{\sim}22.40%$ in cooling load and about $1.09{\sim}24.22%$ in heating load in comparison with existing ones.

• Advances in Energy Research
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• v.5 no.4
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• pp.289-304
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• 2017

Large glazed surfaces and windows become common features in modern buildings. The spread of these features was influenced by the dependence of designers on mechanical and artificial systems to provide occupants with thermal and visual comfort. Countries with hot summer and cold winter conditions, like Jordan, require maximum shading from solar radiation in summer, and maximum exposure in winter to reduce cooling and heating loads respectively. The current research aims at designing optimized double-positioned external shading device systems that help to reduce energy consumption in buildings and provide thermal and visual comfort during both hot and cold seasons. Using energy plus, a whole building energy simulation program, and radiance, Lighting Simulation Tool, with DesignBuilder interface, a series of computer simulations for energy consumption and daylighting performance were conducted for offices with south, east, or west windows. The research was based on comparison to determine the best fit characteristics for two positions of adjustable horizontal louvers on south facade or vertical fins on east and west facades for summer and winter conditions. The adjustable shading systems can be applied for new or retrofitted office or housing buildings. The optimized shading devices for summer and winter positions helped to reduce the net annual energy consumption compared to a base case space with no shading device or with curtains and compared to fix shading devices.

• KIEAE Journal
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• v.15 no.6
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• pp.101-109
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• 2015

Purpose: Glazing and shading devices influence a lot on the thermal and visual environment in office buildings. Solar heat and daylight are contrary concept, therefore proper arrangement of thermal and optical performance is needed when designing a glazing and shading devices. The purpose of this study is to examine the conditions of the glazing and shading devices available for promoting the reduction of cooling loads + lighting loads and the improvement in thermal comfort and visual comfort for the summer season in an office building installed with venetian blind. Method: This study established 12 simulation cases which have different glazings and the positions of venetian blind for evaluating different thermal and optical performance. And by using EnergyPlus v8.1 and Window v7.2 program, we quantitatively analyzed cooling loads + lighting loads, thermal comfort and visual comfort in an office building installed with the glazing and shading devices. Result: Consequently, Case 9(Double Low-E+Exterior Blind) is the best arrangement of solar heat gain and daylight influx, thereby becomes the most excellent case of reducing cooling+lighting loads(46.8%) and simultaneously becomes the enhancement case in thermal comfort. Also, DGI(Daylight glare index) under clear sky conditions in summer was evaluated to be 19.6, and thereby satisfied the recommendation level of allowing visual comfort.

• Journal of the Korean Solar Energy Society
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• v.35 no.2
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• pp.73-83
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• 2015

When it comes to these buildings for business use, cooling load during summertime was reported to have great importance which, as a result, impressively increased interest in Solar Heat Gain Coefficient (SHGC). Such SHGC is considered to be lowered with the help of colors and functions of glass itself, internal shading devices, insulation films and others but basically, these external shading devices for initial blocking that would not allow solar heat to come in from outside the buildings are determined to be most effective. Of many different external shading devices, this thesis conducted an analysis on Exterior Venetian Blind. As for vertical shading devices, previous researches already calculated SHGC conveniently using concepts of sky-opening ratios. However in terms of the Venetian Blind, such correlation is not possibly applied. In light of that, in order to extract a valid correlation, this study first introduced a concept called shape factor, which would use the breadth and a space of a shade, before carrying out the analysis. As a consequence, the concept helped this study to find a very similar correlation. Results of the analysis are summarized as follows. (1) Regarding SHGC depending on the surface reflectance of a shade, an average of 2% error is observed and yet, the figure can always be ignored when it comes to a simple calculation. (2) As for SHGC of each bearing, this study noticed deviations of 4% or less and in the end, it is confirmed that extraction can be achieved with no more than one correlation formula. (3) When only the shape factor and nothing else is used for finding a correlation formula, the formula with a deviation of approximately 5% or less is what one would expect. (4) Since the study observed slight differences in bearings depending on ranges of the shape factors, it needed to extract a weighted value of each bearing, and learned that the smaller the shape factor, the wider the range of a weighted value. The study now suggests that a follow-up research to extract a simple calculation formula by dealing with all these various inclined angles of shade, solar radiation conditions of each region (the ratio of diffuse radiation to direct radiation and others) as well as seasonal features should be carried out.

• The Journal of the Acoustical Society of Korea
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• v.41 no.6
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• pp.621-628
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• 2022

The most realistic way to reduce noise outside the building, such as road traffic noise and aircraft noise, is to strengthen the sound insulation performance at the sound collecting points such as balconies, windows, and exterior walls of each building. However, in light of the reality that shading devices outside buildings are not yet widely used, there are not many studies on sound insulation performance improvement using external windows and window devices such as louvers and blinds. In particular, external blinds can not only block the inflow of strong sunlight in the morning and evening from the outside of the building, but also target the sound insulation effect that blocks the peak noise that occurs during commuting hours. In this study, a study was conducted to improve sound insulation performance against external noise by using an external electric blind (EEB), which is one of the most efficient window and door external shading devices. Various sound insulation performance tests were conducted while changing the configuration of external electric blinds developed for light blocking purposes. Through this, it was verified that an additional sound insulation performance of 6 dB can be obtained by installing an external electric blind compared to the reduction performance of general windows.

• Architectural research
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• v.22 no.2
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• pp.41-52
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• 2020

Laboratory buildings with specialized equipment and ventilation systems pose challenges in terms of efficient energy use and initial construction costs. Additionally, lab spaces should have flexible and efficient layouts and provide a comfortable indoor research environment. Therefore, this study aims to identify the correlation between the facade of a building and its interior layout from case studies of energy-efficient research labs and to propose passive energy design strategies for the establishment of an optimal research environment. The case studies in this paper were selected from the American Institute of Architects Committee on the Environment Top Ten Projects and Leadership in Energy and Environmental Design (LEED) certified research lab projects. In this paper, the passive design strategies of space zoning, façade design devices to control heating and cooling loads were analyzed. Additionally, the relationships between these strategies and the interior lab layouts, lab support spaces, offices, and circulation areas were examined. The following four conclusions were drawn from the analysis of various cases: 1) space zoning for grouping areas with similar energy requirements is performed to concentrate similar heating and cooling demands to simplify the HVAC loads. 2) Public areas such as corridor, atrium, or courtyard can serve as buffer zones that employ passive solar design to minimize the mechanical energy load. 3) A balanced window-to-wall ratio (WWR), exterior shading devices, and natural ventilation systems are applied according to the space programming energy requirements to minimize the dependence on mechanical service. 4) Lastly, typical laboratory space zoning categories can be revised, reversed, and even reconfigured to minimize the energy load and adjust to the site context. This study can provide deep insights into various design strategies employed for construction of green laboratories along with intuitive arrangement of various building components such as laboratory spaces, lab support spaces, office spaces, and common public areas. The key findings of this study can contribute towards creating improved designs of laboratory facilities with reduced carbon footprint and greenhouse emissions.