• Journal of the Korea institute for structural maintenance and inspection
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• v.18 no.1
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• pp.10-18
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• 2014

Mechanically fastening FRP (MF-FRP) strips using nails and anchors, has been shown to provide a more ductile behavior to the strengthened structural element than using bonded FRP. To further advance the state of the knowledge on this strengthening method, the current study examined environmental effects for six months on MF-FRP beams. Reinforced concrete beams strengthened with mechanically fastened FRP strips and subjected to sustained loads for six months were exposed to outdoor weather and constant high temperatures ($40^{\circ}C$). For comparison, the behavior of RC beam with and without sustained loads was evaluated. Results from flexural tests did not show any significant degradation or change of failure mode as a result of sustained load and of environmental effects such as high temperatures and outdoor weather over a period of six months. Failure of the beams was governed by FRP delamination followed by concrete crushing as not much load applied to the nail and anchors because of slip effects.

• Journal of Environmental Policy
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• v.10 no.1
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• pp.27-47
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• 2011

Used as foundation resources for environment improvement and preservation of single-housing residential area by practicing classification of biotope with the concept of ecological area rate applied and performing urban thermal environment prediction simulation. Biotope is classified as seven types according to classification of biotope which is carried out with the concept of ecological area rate applied. The classification is listed below in descending order: building biotope(48.16%), impervious pavement biotope(39.75%), greenspace biotope(6.23%), crack permeable pavement biotope(3.26%), whole surface permeable pavement biotope(2.51%), parts permeable pavement biotope(0.04%). As a result of analysing prediction of variation and characteristics of thermal environment of single-housing residential area, land surface temperature per types of biotope are evaluated as listed below in descending temperature order: impervious pavement biotope > building biotope > greenspace biotope > permeable pavement biotope. In case 2 where vegetated roof hypothetically covers 100% of the roof area, temperature is predicted to be $33.58^{\circ}C$ Max, $23.85^{\circ}C$ Min, and $27.74^{\circ}C$ Avg. which is Approximately $5.19^{\circ}C$ lower than a non-vegetated roof. Average outdoor temperature for case 2 is studied to be $0.18^{\circ}C$ lower than case 1.

• Proceedings of the SAREK Conference
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• 2009.06a
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• pp.561-564
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• 2009

This study is to examine the possibility of pre-cooling at platform. Through measurement of the thermal environment of Bujeon Subway platforms, review the potential use of ground-water and night purge. The results of this research can improve the thermal environment pre-cooling of the design.

• Proceedings of the Korean Society for Bio-Environment Control Conference
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• 1999.11a
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• pp.51-54
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• 1999

1. 하우스 개폐장치 조작 불능시를 가정하여 천ㆍ측창을 인위적으로 폐쇄한 경우, 하우스내 온도는 외기온 보다 16$^{\circ}C$ 높은, 즉 사실상 작물을 생육할 수 없는 고온상태를 나타내었다. 이러한 결과는 하우스 상태 및 외기조건 등에 따라 다소 상이할 것으로 예상된다. 2. 천ㆍ측창을 개방한 상태에서 환기팬을 가동한 경우, 환기팬 가동에 따른 추가적인 실온 저하 효과는 계측되지 않았다. 3. 본 연구에서는 비교적 노즐 입경이 큰 스프링클러를 이용하여 관수시의 냉각효과를 검토하였다. 이 경우, 하우스내 온도는 스프링클러 작동과 동시에 비교적 짧은 시간내에 급격한 온도강하가 이루어졌다. 이 후 지속적인 온도강하는 둔화되어 비교적 안정된 온도를 유지함으로서, 하우스의 실온저하에 크게 기여하고 있음을 확인할 수 있었다.

• Journal of Bio-Environment Control
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• v.24 no.2
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• pp.128-133
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• 2015

Mushrooms can grow in nature when adequate temperature and humidity are maintained, but such condition can be satisfied for only a short period of time on an annual continuum. Therefore, it can be deemed that a majority of the distributed mushrooms in the current market are produced in an artificially manipulated environment. This study was conducted to resolve the problem of the Oyster mushroom cultivation house's internal temperature and humidity imbalance, where the Oyster mushrooms are cultivated in a multi-layered shelves. The air circulation fans were installed to improve the air uniformity of the Oyster mushroom cultivation house by using multi-layered shelves. During the experiment, the ambient temperature and the ambient relative humidity ranged from $5.2^{\circ}C$ to $20.4^{\circ}C$ and 40% to 100% respectively. Due to the change of the outdoor temperature, the internal temperature of the Oyster mushroom cultivation house also changed, ranging from $13.3^{\circ}C$ to $18.4^{\circ}C$, but the temperature gap between the different internal location of the facility during the conforming recorded time only ranged from $0.2^{\circ}C$ to $1.3^{\circ}C$, being significantly stable. The internal relative humidity, ranging from 82% to 96%, also changed due to the change of the outdoor temperature. Nevertheless, the relative humidity gap between the different internal location during the conforming recorded time only ranged from 2% to 7%. Furthermore, the research staff were able to maintain the concentration of $CO_2$ from 575ppm to 731ppm(below 1,000ppm was the goal) indicating the possibility of an even management of the internal environment by installing the air circulation fan.

• The Korean Journal of Mycology
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• v.47 no.2
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• pp.131-142
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• 2019

The Bupjusa and Seonamsa temples are located at places with geographically different condition, and therefore, differ with respect to building's structure and layout. In addition, evident difference can be appeared by the regional climate. For the 2 years, we studied the concentration and diversity of the seasonal airborne fungi inside and outside of the 2 temples. In Seonamsa temple, airborne fungi concentration in the indoor and outdoor air was higher and the species diversity in the indoor air was lower, whereas, concentration variation was larger than that of Bupjusa temple. A total of 173 fungal isolates (including 54 genera) and 162 isolated (including 49 genera) were obtained from the indoor air of Bupjusa and Seonamsa temple, respectively. Whereas, 80 fungal isolates (including 33 genera) and 74 isolates (including 39 genera) were collected form the outdoor air of Bupjusa and Seonamsa temple, respectively. However, more fungal varieties were observed to be distributed inside Bupjusa and outside Seonamsa temples. Amongst all the fungi identified, ascomycetes were more dominant (plus or minus 90% points), followed by basidiomycetes and zygomycetes; which more presented in outdoor air than in indoor air. The airborne fungi concentration in spring (month of April) and autumn was higher than in any other season, for Seonamsa and Bupjusa temples, repectively. Genus Cladosporium was isolated from each site and season, with its dramatic increase noted in autumn. In addition, the highest basidiospore(s) number was obtained after the rain. Consequently, the results suggest that Seonamsa temple was more susceptible to biological damage than Bupjusa temple was.

• Journal of Environmental Science International
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• v.19 no.2
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• pp.125-136
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• 2010

The most important factors relating to the indoor air environment are temperature, airflow, humidity, and contaminant concentration. A sensitivity analysis of indoor environment factors was carried out to grasp influences along with changes of atmospheric conditions. An integrated multizone model was used to predict these sensitivities. This model was applied to an apartment with six zones. Airflow rates are influenced very seriously by changes of wind direct or wind velocity, but are influenced very slightly by changes of outdoor air temperature and are not influenced at all by changes of outdoor air humidity or contaminant concentration. Indoor air temperatures are influenced very directly by changes of outdoor air temperature, but are influenced very slightly by wind direction or wind velocity and are not influenced at all by changes of outdoor air humidity or contaminant concentration. Indoor air humidities are influenced very directly by changes of outdoor air humidity, but are not influenced at all by changes of outdoor air contaminant concentration and have little or no influence by changes of wind direction, wind velocity, or outdoor air temperature. Indoor air contaminant concentrations are influenced very seriously by changes of wind direct or wind velocity, but are influenced somewhat by changes of outdoor air contaminant concentration and are influenced very slightly by changes of outdoor air temperature and are not influenced at all by changes of outdoor air humidity.

• 한국신재생에너지학회:학술대회논문집
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• 2005.06a
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• pp.345-348
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• 2005

본 개발의 목적은 연료전지차량에 탑재되는 연료전지 시스템에 장착될 공기공급기를 개발하는 것이었다. 개발된 공기공급기의 형태는 공급해야 할 공기의 유량과 압력 범위, 소음 및 향후 양산성 등을 고려하여 원심형 블로어를 선택하였으며, 차량 부하에 따른 공기공급량을 제어하기 위한 제어기도 적용되었다. 또한 차량에 적용될 경우, 예상되는 가혹한 사용환경에서 안정적인 성능을 발휘하고, 내구성을 할 수 있도록 설계되었으며, 특히, 외기온도 $45^{\circ}C$에서도 충분한 방열성능을 갖도록 모터 및 모터 방열구조를 설계하였다. 이를 위하여 공급되는 공기로 직접 모터를 냉각하는 개념을 적용하였다. 개발된 터보블로어의 응답성을 포함한 성능평가를 수행하였으며, 설계점에서 600시간 연속운전을 통하여 기본 내구평가를 완료하였다.

• Proceedings of the KIEE Conference
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• 2005.07b
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• pp.1693-1695
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• 2005

최근 공공건물에 신재생에너지 적용이 의무화되었고, 기후변화협약의 발효로 이산화탄소배출 절감에 대한 관심이 매우 높다. 가장 효율이 높은 냉난방 시스템인 지열히트펌프를 대표적인 신재생에너지인 태양광발전을 이용하여 구동하여 건물을 냉난방을 수행하도록 적용되었다. 야간 또는 태양에너지 밀도가 낮은 날을 위하여 축열과 축냉을 할 수 있는 수축열시스템과 연계하여 적용되었다. 지열히트펌프는 도심지역의 열섬현상 해소에 기여할 수 있으며, 외기 온도의 변화에 관계없이 쾌적한 실내환경을 유지할 수 있으며 향후에 그린 빌딩인증등을 위해 에너지 절약과 신재생에너지 사용량을 높일 수 있는 방안으로 판단된다. 이를 적용한 설치 사례에 대한 사양과 운전 조건이 제시된다.

• Journal of the Korean Society for Geothermal and Hydrothermal Energy
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• v.14 no.4
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• pp.13-19
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• 2018

The Effects of hot water supply temperature on indoor thermal characteristics for floor radiant heating system in residential apartment were researched by computer simulation. The parametric study on hot water supply temperatures with different outdoor air temperatures was done with regard to energy performance and control characteristics, respectively. As a result, the maximum overshoot of indoor air temperature and energy consumption were reduced by adjusting the hot water supply temperatures with outdoor air temperatures.