• Journal of the Korean Solar Energy Society
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• v.24 no.4
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• pp.45-53
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• 2004

In the summer, the irradiated solar heat gain through the roof has an effect on the thermal environment of the top floor units of apartment houses. This paper investigated the differences of the indoor air temperature and thermal comfort index between the top floor unit and the middle floor unit by measuring them at the sample houses. The purpose of this paper is to provide quantitative data about the irradiated solar heat gain during the summertime through the roof of an apartment house and these data to be the source to reevaluate the appropriate roof insulation efficiency. From this study, we obtained the brief results as follows. Indoor air temperature at the top floor unit is $1.2\sim2.2^{\circ}C$ higher than that of middle floor unit. The evaluation of the indoor thermal comfort index at each sample rooms reveals notable thermal differences between the two units. Top floor units need more cooling load during the summertime compared to middle floor units. Therefore, solutions to reduce solar Heat gain at top floor units to be considered.

• Journal of the Korean housing association
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• v.20 no.3
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• pp.105-112
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• 2009

The purpose of this study is to investigate a top floor, indoor, thermal environment by comparison between the indoor air temperature and the rooftop surface temperature, and between the indoor air temperature and the outdoor air temperature using an experimental model. The model experiment was conducted with 4 cases,: no-rainfall, 1 em-height, 10 em-height and 20em-height of rainfall on the rooftop. According to the results of the height of stored rainfall, the average air temperature difference between the indoor and outdoor air with 1, 10 and 20 em-height of rainfall on the rooftop was $4.0^{\circ}C$, rooftop $1.2^{\circ}C$ and rooftop $1.0^{\circ}C$, respectively. The upper 10 em-height of rainfall on the rooftop acted to decrease the indoor air temperature on the top floor.

• Earthquakes and Structures
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• v.20 no.1
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• pp.29-38
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• 2021

According to ACI 224.3R-95 (ACI, 2013), construction joints (cold joint) in the column are to be provided at the top of floor slab for column continuing to the next floor and underside of floor slab and beam. A recent study reveals that providing cold joint of the mentioned location significantly reduced the seismic performance of the frame structures. Since, the construction joints in multi-story frame structures normally provided at the top of the floor slabs and at soffit of the beam in the column. This study investigated the effect of construction joint at various location in the column of beam-column joint such as at the top of floor slab, soffit level of the beam, half the depth of beam below the soffit of the beam and at a full depth of the beam below the soffit of the beam. The study revealed that there is an improvement in seismic capacity of the specimens as the location of cold joint is placed away from the soffit of the beam for lower story column.

• Journal of the Korean Solar Energy Society
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• v.25 no.1
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• pp.45-55
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• 2005

In the summer, the irradiated solar heat gain through the roof has an effect on the thermal environment of the top floor units of apartment houses. This paper investigated the differences of the indoor air temperature, globe temperature and thermal comfort index between the top floor unit and the middle floor unit by measuring them at the sample units on the condition that all the openings of the units are opened. The purpose of this paper is to provide quantitative data about the irradiated solar heat gain during the summertime through the roof of an apartment house and these data to be the source to reevaluate the appropriate roof insulation efficiency. From this study, we obtained three brief results as follows. Indoor air temperature difference between the two sample units shifts a day. Indoor air temperature at the top floor unit is $0{\sim}1.8^{\circ}C$ higher than that of the middle floor unit from 12:00 p.m. to 12:00 a.m. and $0{\sim}2.8^{\circ}C$ lower from 12:00 a.m. to 12:00 p.m. The evaluation of the indoor thermal comfort index and the globe temperature shows similar results as the indoor air temperature measuring. Results of this experiment verified the actual existence of indoor air temperature difference between the top floor unit and the middle one and this difference comes from the heat storage of the roof.

• Journal of Environmental Impact Assessment
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• v.20 no.4
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• pp.465-475
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• 2011

It is known that energy consumption in bottom floor of typical Korean-style apartment is the highest. Previous studies for energy consumption in accordance with floor level appear to be very limited due to the dependence on single energy variable such as electric power or LNG separately, based on past flat type of apartment. Acknowledging these constraints, an empirical study for a tower type emerged recently as new style of apartment in South Korea was conducted to demonstrate how a comprehensive evaluation for both electric power and LNG consumption can be used to assist in monitoring the total energy consumption in terms of floor specific settings. It was possible to identify that energy consumption in bottom floor is lesser than that of top floor, to the contrary, fact known from previous study. Also electric power consumption in top floor was identified as 15% higher than that of floor in the least. It is anticipated that this integrated utilization of electric power and LNG data would present more scientific and objective evidence for the energy load among floor level of tower type apartment by overcoming serious constraints suffered from the past single variable investigation. Ultimately, the result in this paper could be used as a valuable reference to providing priority for energy saving activities in top floor such as cool roof or green roof.

• Journal of the Korean Solar Energy Society
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• v.31 no.6
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• pp.132-138
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• 2011

Inducing the natural lighting into building has been commonly applied to the spaces where artistic objects are displayed to create better visual environment for the appreciation. The direct natural lighting, especially through top lighting system may, however, bring forth discoloing of highly light-sensitive materials such as paintings or demanding additional cooling load. In addition, it causes to create glare against appreciators or to yield in visual distraction due to the extreme contrast on the inner surfaces of the spaces. Shading device such as louver is capable of preventing such voidable cases with careful manipulation. This study aims to provide basic design guide-line when the flat-form louver has to be applied to top lighting system. Interaction between the daylight and louver was simulated by Reluxpro program with variation of the attachment location, the angle of the lover, surface reflectivity, to obtain the illumination of the floor surface. This study yields the louver just under the top lighting window with 90 degree angle gives the most desirable way of employment when the uniform illumination on the floor surface is required.

• International Journal of High-Rise Buildings
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• v.1 no.4
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• pp.311-332
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• 2012

Earthquake response of mid-rise to high-rise buildings provided with friction dampers is investigated. The steel buildings are modelled as shear-type structures and the investigation involved modelling of the structures of varying heights ranging from five storeys to twenty storeys, in steps of five storeys, subjected to real earthquake ground motions. Three basic types of structures considered in the study are: moment resisting frame (MRF), braced frame (BF), and friction damper frame (FDF). Mathematical modelling of the friction dampers involved simulation of the two distinct phases namely, the stick phase and the slip phase. Dynamic time history analyses are carried out to study the variation of the top floor acceleration, top floor displacement, storey shear, and base-shear. Further, energy plots are obtained to investigate the energy dissipation by the friction dampers. It is seen that substantial earthquake response reduction is achieved with the provision of the friction dampers in the mid-rise and high-rise buildings. The provision of the friction dampers always reduces the base-shear. It is also seen from the fast Fourier transform (FFT) of the top floor acceleration that there is substantial reduction in the peak response; however, the higher frequency content in the response has increased. For the structures considered, the top floor displacements are lesser in the FDF than in the MRF; however, the top floor displacements are marginally larger in the FDF than in the BF.

• 한국태양에너지학회:학술대회논문집
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• 2012.03a
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• pp.445-450
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• 2012

BIPV/T (Building Intergrated PhotoVoltaic/Thermal) is combined system produces electricity and thermal energy. The heat from PV modules should be removed for better electrical performance, and can be converted into useful thermal energy. The efficiency of the PV system's performance will raise by the system removes heat from the PV. The test system is installed to top floor of the experimental house in the KEPCO Research Institute. The planned experiment is following. (1) Supplying heat energy to top floor. (2) Supplying heat and cool energy to thermal storage in the bottom of the top floor. (3) Supplying heat energy to EHP for improved performance. The experimental performance is executed from 13th February to 13th March, 2012. The solar generation of electricity is 4.04kWh under the horizontal solar radiation is $1000W/m^2$ and the air temperature is $25^{\circ}C$.

• Journal of the Architectural Institute of Korea Structure & Construction
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• v.35 no.6
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• pp.101-109
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• 2019

The purpose of this study is to improve a general Top-Down construction process for superstructure construction period reduction. In a general Top-Down construction sequence, the ground floor slab is set up first. Subsequently, 1st basement level construction including core walls is constructed. Initiation of the ground level superstructure gets waited until then. In this study, removable deck plate installation on the bottom of the core walls of ground level is preceding the concrete casting, therefore, ground level superstructure construction is able to get started earlier. Up to first typical floor concrete casting, total of seventy-two working(calendar) days will be resulted in a reduction from the total construction periods.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2016.05a
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• pp.111-112
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• 2016

Waterproofing methods for applying to roof-top in the building are various, but it is not enough to development, which are simplified and low-cost method for old building. Especially, these buildings have not only a low insulation, but a disadvantage for energy. A floating floor method is necessary for this. This study performs an experimentt about bonding capacity of complex panel for waterproofing and heat insulation. The bond strength experiment is based on KS F 4716, and it is considered by bond mix proportion about panel and slab.