• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2008.04a
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• pp.260-263
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• 2008

공항에 인접한 주거지역에서 항공기 소음문제로 인하여 거주자들에게 소음피해가 발생하고 있다. 이러한 항공기소음을 저감하기 위한 방법 중 건물외피를 차음성능이 높은 구조로 변경하여 건축물의 차음량을 개선시키는 수음원 대책이 일반적으로 사용되고 있다. 특히 건축물 방음시설 설치는 건물외피 중 외부소음에 가장 취약한 창호의 차음량을 증가시키는 것이 효과적인데, 본 연구에서는 기존 창호에 비하여 차음성능이 높은 창호를 교체 설치하여 건축물의 차음량 개선치를 $L_{max}$, SEL, $L_{eq}$로 각각 검토 비교함과 동시에 창호의 기밀성능을 위한 기밀재 및 추가 모헤어의 설치조건에 따른 차음성능을 검토해 보았다. 측정결과 방음시설 설치 후 항공기소음을 $L_{max}$, SEL, $L_{eq}$로 차음량 개선치를 각각 평가한 결과 1.8dB 이내의 편차를 갖는 것으로 나타났으며, 창의 차음성능 개선치는 기밀재 설치 후 $R'45^{\circ}$,w가 5dB, 기밀재 및 추가 모헤어 설치 후 8dB로 나타났다.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2008.04a
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• pp.276-279
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• 2008

In order to measure sound transmission loss (STL) of a shipboard window of small size, a special partition is built into the test opening between two reverberation rooms and the specimen is placed in that partition. For high sound insulation, the filler wall often has multi-layered structure such as double-brick wall or buckhead structure with thick steel plate, absorptive material, and sandwich panels. This paper discusses the installation method of a multi-layered filler wall that consist of gypsum boards, lead plates, and glass wool. The experimental results of various wall structures are introduced. The comparison between the results show that the sound bridge effect plays a significant role in lowering the maximum STL of the filler wall. It is also found that the higher the sound insulation performance of the filler wall is, the more important the franking transmission through other side wall of the test facility is.

• The Proceedings of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.8 no.2
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• pp.33-40
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• 1994

This study investigates the relationship between size, illumination, and display of show window. The average width, height, and depth of show windows in Taegu area were 341.3, 233.4, and 125.8cm, respectively. As light source, halogen lamp was most frequently used, followed by fluorescent lamp and incandescence lamp. In the actual illumination, however, a combined use of more than 2 light sources was common Further, a local illumination method, e. g., spot light, was generally adopted. The thought of employers and employees in fashion shops on display and illumination was examined as well. On the whole, the necessity and importance of display were well recognized but the fact that the illumination should be harmonized with other factors such as color and arrangement of goods was underestimated.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.28 no.2
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• pp.63-68
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• 2016

To study the effect of installation and the shapes of filling pieces used for windows on the infiltration rate, infiltration tests were performed with two types of sliding windows and two shapes for the filling pieces. Infiltration occurred most at the top and bottom parts of the center location where two windows overlap, indicating the necessity of a filling piece to be installed at these locations. Infiltration velocity is proportional to the square root of the pressure difference, complying well with the theoretical correlation. Infiltration is reduced about 50% by the filling piece installation. This study shows that filling pieces are essential and their shapes play significant roles in reducing the infiltration of windows.

• Ocean Systems Engineering
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• v.12 no.4
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• pp.413-437
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• 2022

An innovative concept for wet-transportation and stepwise installation of mono-bucket foundation for 15 MW offshore wind turbine is proposed. Case studies for two different mono-bucket and wrap-buoy dimensions are conducted and their hydrostatic and hydrodynamic performances are compared for both wet-towing and lowering operations. The intact stability and transient responses are analyzed in detail for various stages of lowering operation. Wave-induced motion statistics during wet tow in sea state 4 (highest operational window) are checked. The proposed concept is found to be feasible and can be an alternative cost-effective solution without using heavy-lift crane vessel in practice.

• Korean Journal of Agricultural Science
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• v.39 no.2
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• pp.271-277
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• 2012

Dimensions, operation conditions and improvement items for round roof windows were investigated in arch shape single-span plastic greenhouse with roof vents, and natural ventilation performance was analyzed based on the ventilation theory. Diameter of round roof windows was mostly 60 cm, and chimney height projected on roof was average 30 cm. Installation space was mostly 5 to 6 m but farmhouse of 10 m and over was 16.7% also. A round roof window which has 60 cm diameter was installed to 6 m space generally and 80 cm diameter was installed to 10 m space, but correct standards did not exist. There were a lot of opinions that ventilation effect of round roof windows is fairly good and user satisfaction is generally excellent. It is problem that there is few effects in summer and that vinyl around each vent tears well and rainwater leaks, and improvement hope item required development of automatic control system. In the wind speed of 0.3 m/s, it was estimated that natural ventilation rates were 0.69, 0.55, 0.50 and 0.48 volumes per minute in case of 2, 4, 6 and 8 m installation space for round roof windows, respectively. It was analyzed that the ratio of ventilation due to buoyancy out of total ventilation were 65.2, 41.9, 29.9 and 22.8% in case of 2, 4, 6 and 8m installation space, respectively. By the round roof windows installed at space of 6 m, ventilation rate was estimated to 0.5 volumes per minute, and we can expect the increase in ventilation rate of 30%. In order to meet the recommended ventilation rate for summer season, we have to install the round roof windows at space of 1 to 2 m. However, it is difficult to apply those installation space because of falling productivity due to lower light transmittance as well as rising costs. It is estimated that the installation space of 6m is appropriate for spring or fall season. Therefore it is necessary to encourage installing the roof windows in single-span plastic greenhouses.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.21 no.3
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• pp.18-26
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• 2007

One basic function of glazing system has always been the maintenance of visual contact with the natural environment-a fundamentally ecological function. In addition, penetration light through glazing system have an effect on variable atmosphere of interior. In this study, a typical office space was selected as a evaluation model and a 1/10 scale model was made. The conventional window, differentiated window and interior lightshelf were designed to enhance daylighting performance. The chromaticity and color temperature of interior space was measured using Prometric 1421. The result showed that transmittance by wavelength range of the glazing had an effect on chromaticity and color temperature. Also, color temperature of indoor environment were increased by $5{\sim}20[%]$ using differentiated window and interior lightshelf. Accordingly, it is thought that the use of a daylighting system will create activate indoor atmosphere.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.23 no.2
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• pp.36-44
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• 2009

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 yard comes in the inside of the floor. As the layer of window is increased, daylight is decreased and the illuminance distribution is more stable because of decreasing of illuminance changes. Also, the lower part luminance is higher than upper part of window surface because direct sunlight is cut off by the eaves. This study would be used as preliminary data for applying characteristics of lighting environment of Korean royal palace to modem architecture.

• Journal of the Architectural Institute of Korea Planning & Design
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• v.35 no.11
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• pp.25-34
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• 2019

It is important to design windows in a reasonable way considering the performance characteristics of the elements of the window rather than just to increase the thermal energy performance of the window. In this study, the Heat-transfer Coefficient as insulation performance of the windows and together with the grade of the glass's SHGC (Solar Heat Gain Coefficient) were analyzed to relate to the energy efficiency performance of the building by azimuth angle. Based on this basic study, the Heat-transfer Coefficient of windows and the SHGC rating of glass were applied to the unit plan of apartment building, and the Heating and Cooling Demand were analyzed by azimuth angle. Apartment plan types were divided into 2 types of Non-extension and extension of balcony. The designPH analysis data derived from the variant of the Heat-transfer Coefficient and SHGC, were put into PHPP(Passive House Planning Package) to analyze precisely the energy efficiency(Heating and Cooling Demands) of the building by azimuth angle. In addition, assuming the 'ㅁ' shape layout, energy efficiency performance and potential of PV Panel installation also were analyzed by floors and azimuth angle, reflecting the shading effects by surrounding buildings. As the results of the study, the effect of Heat Gain by SHGC was greater than Heat Loss due to the Heat-transfer Coefficient. So it is more effective to increase SHGC to satisfy the same Heating Demand, and increasing SHGC made possible to design windows with low Heat-transfer Coefficient. It was also revealed that the difference in annual Heating and Cooling Demands between the low, mid and high floor households is significantly high. In addition to it, the installation of PV Panel in the form of a shading canopy over the window reduces the Cooling Load while at the same time producing electricity, and also confirmed that absolute thermal energy efficiency could not be maximized without controlling the thermal bridge and ventilation problems as important heat loss factors.

• Journal of Environmental Impact Assessment
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• v.15 no.5
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• pp.289-297
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• 2006

The study investigates the problems of silt protector used for mitigation measure of suspended sediments (SS) during coastal construction and provides their improvements based on the field investigation and analysis of the environmental impact assessment reports for the coastal development projects of Korea. The field investigation along west, east and south coasts of Korea reveals a variety of problems in the installation and management of silt protector solely used for the SS mitigation in Korea. Major problems include installation itself, low cost and quality of silt protector, and maintenance. These problems superimpose the effectiveness of silt protector in mitigating coastal environment impact. The present study provides the specific guideline on the project type needed for the installation of silt protector, installation standard and planning, maintenance and management. The study also suggests new mitigation options such as environmental window to limit the construction period and environmental dredger to compensate for the deficits of silt protector.