• Journal of the Korean earth science society
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• v.40 no.2
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• pp.119-134
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• 2019

In order to analyze the observational environment of solar radiation stations operated by the Korea Meteorological Administration (KMA), we used the digital elevation model (DEM) and the solar radiation model to calculate a topographical shading, sky view factor (SVF) and solar radiation by surrounding terrain. The sky line and SVF were calculated using high resolution DEM around 25 km of the solar stations. We analyzed the topographic effect by analyzing overlapped solar map with sky line. Particularly, Incheon station has low SVF whereas Cheongsong and Chupungryong station have high SVF. In order to validation the contribution of topographic effect, the solar radiation calculated using GWNU solar radiation model according to the sky line and SVF under the same meteorological conditions. As a result, direct, diffuse and global solar radiation were decreased by 12.0, 5.6, and 4.7% compared to plane surface on Cheongsong station. The 6 stations were decreased amount of mean daily solar radiation to the annual solar radiation. Among 42 stations, eight stations were analyzed as the urgent transfer stations or moving equipment quickly and more than half of stations (24) were required to review the observational environment. Since the DEM data do not include artifacts and vegetation around the station, the stations need a detail survey of observational environment.

• Journal of the Korean Solar Energy Society
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• v.27 no.4
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• pp.137-146
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• 2007

This study is about the passive cooling effects of three outdoor solar shading facilities as trees, pergola with wistaria vine and membrane shading structure, which are expected to provide cool spots in the summer. Field observations of measuring thermal environment of selected facilities is executed. Thermal environment measuring was categorized as short wave radiation, long wave radiation, net radiation, globe temperature, surface temperature measured by infrared camera. Heat transfer mechanism is analyzed with overall data from field measurement. Results from this study are as below; 1) Radiation balance measured on shaded surface under membrane shading structure was 17%($86W/m^2$) of the unshaded surface radiation balance($511W/m^2$). 2) Surface temperature comparison between vegetation and membrane of the shading structure is performed at 3 o'clock in the afternoon. Surface temperature of vegetation was same as air temperature and that of membrane was $5^{\circ}C$ higher than air temperature. Vegetation transpiration is considered as the causing factor which make those differences. 3) Results from this study could be used as fundamental data for reducing heat island phenomena and continuos research on this subject would be needed.

• Journal of the Korean Solar Energy Society
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• v.36 no.4
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• pp.1-9
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• 2016

The purpose of this study was to compare heat shading performance of various blind types in summer. 4 types of blinds were employed and the results are summarized as follows: 1) There were significant differences in indoor thermal environment and heat shading performance between different heat shading devices, and functional blinds demonstrated relatively superior heat shading performance. 2) Indoor long wave radiation influx measures were lowest for the coating roll blind (Blind B), followed by the coating venetian blind (Blind C), the venetian blind (Blind A), the roll blind, and not having any blinds at all. 3) Such examination results carry implications to reduce cooling load and enhance the indoor environment.

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2003.05b
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• pp.417-418
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• 2003

2002년 10월과 11월에는 가을 추수 후 소각이 대기질에 미치는 영향을 조사하고자 광주과학기술원 내에서 에어로졸과 대기 복사 집중 측정 기간을 가졌다. 12시간 또는 일평균 자료만을 제공하는 에어로졸 화학적 특성의 측정과 달리 자외선 영역의 다파장 회전차폐판 복사계 (Ultraviolet Multi-filter Rotating Shadowband Radiometer)를 이용한 에어로졸 광학 깊이(aerosol optical depth)는 1분 간격의 직달 일사량 자료로부터 에어로졸 복사적 특성을 시간에 따른 변화를 볼 수 있다는 장점을 가진다. (중략)

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2008.04a
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• pp.672-674
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• 2008

• Proceedings of the Korean Vacuum Society Conference
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• 2011.08a
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• pp.221-221
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• 2011

최근, 대외적으로 기후변화협약 등 환경에 대한 관심이 높아지면서 국내에서도 온실가스 배출이 큰 에너지의 22.3%를 소비하고 있는 건축물로 인한 환경부하에 관심이 높아지며 고효율 창호의 필요성이 대두되고 있다. 기존의 Low-E (저방사) 유리는 적외선을 반사시켜 단열 유리로서 겨울철에 유리하지만, 건물 전면에 약 50~95% 창호가 사용되는 office 건물에는 여름철 냉방에너지를 많이 사용하기 때문에 단열뿐만 아니라 일사 차폐가 가능한 근적외선 차폐유리가 필요하다. 따라서 본 연구에서는 기존의 Low-E 유리의 문제점인 근적외선 투과문제를 해결하기 위한 기술로서 근적외선 영역을 선택적으로 차폐할 수 있는 박막코팅 물질(흡수체, 반사체) 및 Low-E 대체용 Themochromic 등 나노 박막을 RF magnetron sputtering으로 제조하여 복층유리 구조로 조합해 UV-visible을 측정하였으며 IR Lamp와 태양광 아래에서 온도변화 실험을 진행하였다. 그 결과, 기존 Low-E 복층유리 대비 본 실험에서 사용한 복층유리의 근적외선 차폐효율이 개선됨을 확인하였다.

• Journal of the Korean Solar Energy Society
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• v.30 no.3
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• pp.108-115
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• 2010

Global warming and heat island make the outdoor air temperature ascend. Tall office buildings are covered with glass window facades as a design aspect and the portion of window area to facade area is increasing. Hence, cooling load for solar radiation passing through glass window is rising. Cooling air to a certain room is supplied equally despite the face of the room in most office buildings. Especially, the west part of the office cannot maintain the required temperature that occupant needs because of the solar heat coming through windows.?In this study, we projected the water spray system to reduce the solar heat transfer and to reflect the solar ray through windows. We perform the experiments to evaluate the performance of the solar heat protection devices. We measured the room temperature of two separated office rooms for solar heat control devices. The investigation's results show that the water spray system is sufficient to the coated glass and the venetian blinds for the decrease of the solar heat inflow.

• Journal of the Korean Solar Energy Society
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• v.34 no.6
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• pp.75-83
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• 2014

Heat loss through windows and doors occupies 20 to 45% of the total heat loss in building. It accounts for a large proportion of the total heat loss in building. In order to suppress the amount of heat flow through the windows and doors were considered actions such as reinforcement of insulation performance of window, adoption of low-e glass, and installation of solar heat shading device. The Purpose of this study is to compare solar heat shading performances of 3 types of internal blinds in the summer. In order to verify the solar heat shading performances of the blinds, a roll blind, blind A(Venetian blind) and blind B(Daylight guiding venetian blind)were installed in the four rooms with the same environmental conditions. As a result of the experiment, the blind B, blind A, roll blind showed an excellent performance in that order. Its because the blind B is made of aluminum materials coated with special paints on surface. It doesn't converted to long wave by short wave light. and it is reflected to short wave to outside.

• Journal of the Korean earth science society
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• v.38 no.2
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• pp.129-140
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• 2017

Global solar radiation was calculated in this research using ground-base measurement data, meteorological satellite data, and GWNU (Gangneung-Wonju National University) solar radiation model. We also analyzed the accuracy of the GWNU model by comparing the observed solar radiation according to the total cloud cover. Our research was based on the global solar radiation of the GWNU radiation site in 2012, observation data such as temperature and pressure, humidity, aerosol, total ozone amount data from the Ozone Monitoring Instrument (OMI) sensor, and Skyview data used for evaluation of cloud mask and total cloud cover. On a clear day when the total cloud cover was 0 tenth, the calculated global solar radiations using the GWNU model had a high correlation coefficient of 0.98 compared with the observed solar radiation, but root mean square error (RMSE) was relatively high, i.e., $36.62Wm^{-2}$. The Skyview equipment was unable to determine the meteorological condition such as thin clouds, mist, and haze. On a cloudy day, regression equations were used for the radiation model to correct the effect of clouds. The correlation coefficient was 0.92, but the RMSE was high, i.e., $99.50Wm^{-2}$. For more accurate analysis, additional analysis of various elements including shielding of the direct radiation component and cloud optical thickness is required. The results of this study can be useful in the area where the global solar radiation is not observed by calculating the global solar radiation per minute or time.

• Journal of the Korean Institute of Landscape Architecture
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• v.42 no.5
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• pp.22-30
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• 2014

The purpose of this study was to compare the Solar Radiation(SR) and the Mean Radiant Temperature(MRT) under the shades of the three landscaping trees in clear summer daytimes. The trees were Lagerstroemia indica, Quercus palustris and Ulmus parvifolia. The solar radiation, the globe temperature and the air temperature were recorded every minute from the $1^{st}$ of April to the $30^{th}$ of September 2013 at a height of 1.1m above on the four monitoring stations, with four same measuring system consisting of a solar radiation sensor, two resistance temperature detectors(Pt-100), a black brass globe (${\phi}50mm$) and data acquisition systems. At the same time, the sky view photos were taken automatically hourly by three scouting cameras(lens angle: $60^{\circ}$) fixed at each monitoring station. Based on the 258 daily sky view photos and 6,640 records of middays(10 A.M.~2 P.M.) from the $1^{st}$ of June to the $30^{th}$ of August, the time serial differences of SR and MRT under the trees were analysed and compared with those of open sky, The major findings were as follows; 1. The average ratio of sky views screened by the canopies of Quercus palustris, Lagerstroemia indica and Ulmus parvifolia were 99%, 98% and 97%, and the SR were $106W/m^2$, $163W/m^2$ and $202W/m^2$ respectively, while the SR of open sky was $823W/m^2$. Which shows the canopies blocked at least 70% of natural SR. 2. The average MRT under the canopies of Quercus palustris, Lagerstroemia indica and Ulmus parvifolia were $30.34^{\circ}C$, $33.34^{\circ}C$ and $34.77^{\circ}C$ respectively, while that of open sky was $46.0^{\circ}C$. Therefore, it can be said that the tree canopies can reduce the MRT around $10{\sim}16^{\circ}C$. 3. The regression test showed significant linear relationship between the SR and MRT. In summary, the performances of the landscaping shade trees were very good at screening the SR and reducing the MRT at the outdoor of summer middays. Therefore, it can be apparently said that the more shade trees or forest at the outdoor, the more effective in conditioning the outdoor space reducing the MRT and the useless SR for human activities in summertime.