• 한국태양에너지학회 논문집
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• 제37권1호
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• pp.71-80
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• 2017

A Data center houses a large number of server computers, storage and etc in racks. With the rapid increase of heat generation rates per rack in a data center, energy consumption rates for cooling have been increased year by year. In this study, energy conservation effects of a MOA (multi-stage outdoor air enabled) cooling system in a data center has been investigated when it is applied to 5 different locations, Korea. As results, Energy conservation effects of the MOA cooling system was achieved at about 20% to 30%. Humidifier operation time was 40 to 55 days when supply air temperature was maintained at 13, and humidity condition was kept within the allowed range even though humidifier was off. Furthermore, humidification was not needed when supply air temperature was maintained at $25^{\circ}C$. In selected 5 locations in Korea, the difference of regional climatic conditions affected no more than 5% in cooling energy consumption rates.

• Asian Journal of Atmospheric Environment
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• 제12권2호
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• pp.87-108
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• 2018

Schools are one of the critical social infrastructures in a society, the first place for social activity and the most important indoor environment for children besides the home. Poor IAQ in classrooms can increase the chance of long-term and short-term health problems for students and staffs; affects productivity of teachers; and degrade the student learning environment and comfort levels. The primary objective of this paper is to review and summarize available scientific evidence on indoor air quality of schools and related health effects in children. It was found that the indoor air pollutant levels in school buildings varied over a wide range in different parts of the world depending on site characteristics, climatic conditions, outdoor pollution levels, occupant activities, ventilation type and building practices. Among the indoor air pollutants, particulate matter concentrations were found to be very high in many schools. Outdoor pollutant sources also play a major role in affecting the IAQ of the school building. Hence, scientific knowledge on sources of indoor pollutants, quantification of emissions, temporal and spatial dispersion of pollutants, toxicological properties, chemical and morphological characteristics of the pollutants and associated health risk among children in the school buildings are essential to evaluate the adequacy and cost effectiveness of control strategies for mitigating the IAQ issues.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2002년도 하계학술대회 논문집 C
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• pp.1903-1905
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• 2002

The degree of contamination on outdoor insulator is one of the most important factors for the determination of insulation level. And the salt, NaCl, is known as the most dangerous contaminants in the most region of the world. As shown through the preceding study, we could find the close relationship between the generation and deposition of salt contaminants and the meteorological conditions. To analyze the relationship, we monthly measured the ESDD for some sites with brush wiping method, and daily measured the density for one site with the automatic measuring apparatus. And, with the measured data and the meteorological data from KMA(Korea Meteorological Administration), we analyzed the relationship between the two factors with regression method. Through the results of this investigation, we could quantify the comparative contribution of the climatic factors for the pollution level of outdoor insulator, and the results could be used as a useful reference for the maintenance of overhead lines and substations.

• Corrosion Science and Technology
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• 제16권5호
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• pp.241-246
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• 2017

The comparative results of corrosion testing in humid tropical atmosphere in rural and coastal areas for hot dipped zinc coatings are presented below. The test was conducted in outdoor conditions over a period of five years. The mass loss and other performance characteristics of two types of zinc coatings were evaluated, analysed and discussed in relation to the climatic and environmental parameters. The corrosion rates of the coatings exposed to coastal conditions were about three times higher than the corrosion rates appreciated in rural conditions. The data demonstrates that the corrosion process obeys an equation of the form $M=At^n$, where M is the loss of metal and t is the time of exposure. A and n are constants which values depend on the environmental characteristics and the physicochemical behavior of the corrosion products respectively. Corrosion is strongly influenced by atmospheric time of wetness (TOW) and airborne salinity. The nature and composition of corrosion products are also considered. Simonkolleite, a major crystalline phase, was found in the zinc corrosion products exposed to coastal conditions, while zinc hydroxide and zinc hydrosulfate are easily found in rural settings.

• 대한인간공학회지
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• 제36권3호
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• pp.169-181
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• 2017

Objective: The aim of this study was to explore the influence of outdoor weather conditions on subjective responses during physical activity. Background: The largest difference between indoor and outdoor conditions is the existence of the sun. The heat load from the sun has an influence on the heat gain of the human body and the intense degree of solar radiation affected thermal comfort. Method: Thirty eight people were exposed to a range of climatic conditions in the UK. Weather in England does not have extremely hot and cold temperature, and the current study was conducted under warm (summer and autumn) and cool (spring and summer) climates. Measurements of the climate included air temperature, radiant temperature (including solar load), humidity and wind around the subjects. Subjective responses were taken and physiological measurements included internal body temperature, heart rate and sweat loss. Results: This study was conducted under four kinds of environmental conditions and the environmental measurement was performed in September, December, March, and June. The values for sensation, comfort, preference, and pleasantness about four conditions were from 'neutral' to 'warm', from 'not uncomfortable' to 'slightly comfortable', from 'slightly cooler' to 'slightly warmer', and from 'neither pleasant nor unpleasant' and 'slightly unpleasant', respectively. All subjective responses showed differences depending on air temperature and wind speed, and had correlations with air temperature and wind speed (p<0.05). However, subjective responses showed no differences depending on the radiant temperature. The combined effects of environmental parameters were showed on some subjective responses. The combined effects of air temperature and radiant temperature on thermal sensation and pleasantness were significant. The combined effects of metabolic rate with air temperature, wind speed and solar radiation respectively have influences on some subjective responses. In the case of the relationships among subjective responses, thermal sensation had significant correlations with all subjective responses. The largest relationship was shown between preference and thermal sensation but acceptance showed the lowest relationship with the other subjective responses. Conclusion: The ranges of air temperature, radiant temperature, wind speed and solar radiation were $6.7^{\circ}C$ to $24.7^{\circ}C$, $17.9^{\circ}C$ to $56.6^{\circ}C$, $0.84ms^{-1}$ to $2.4ms^{-1}$, and $123Wm^{-2}$ to $876Wm^{-2}$ respectively. Each of air temperature and wind speed had significant relationships with subjective responses. The combined effects of environmental parameters on subjective responses were shown. Each radiant temperature and solar radiation did not show any relationships with subjective responses but the combinations of each radiant temperature and solar radiation with other environmental parameters had influences on subjective responses. The combinations of metabolic rate with air temperature, wind speed and solar radiation respectively have influences on subjective responses although metabolic rate alone hardly made influences on them. There were also significant relationships among subjective responses, and pleasantness generally showed relatively high relationships with comfort, preference, acceptance and satisfaction. Application: Subjective responses might be utilized to predict thermal stress of human and the application products reflecting human subjective responses might apply to the different fields such as fashion technology, wearable devices, and environmental design considering human's response etc.

• 설비공학논문집
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• 제25권10호
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• pp.529-533
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• 2013

Heat-recovery ventilators are being adopted in most newly built apartment houses for energy reduction and indoor environment improvement. In winter, however, the dew condensation resulting from the difference between the indoor and outdoor temperatures may reduce the ventilator's performance and threaten the health of indoor residents. This study analyzes the occurrence of dew condensation according to the ventilator's operational conditions and the changes of temperature and products. The experimental results show that condensations is formed at $26^{\circ}C$ and 60%R.H, which is an unfavorable climatic condition, and when the damper is not closed tightly. Therefore it is important to ensure damper performance to prevent back flow.

• 한국균학회지
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• 제13권2호
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• pp.115-121
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• 1985

우리나라 서울 지역의 상업지역, 교통지역, 주택지역, 공장지역, 목욕탕, 백화점, 병원지역 등을 대상으로 open plate method를 사용하여 공중균을 분리한 결과 총 2,227개의 spore를 분리하였다. 그중 Cladosporium이 1,008 spores, Penicillium이 351 spores, Alternaria가 234s, Aspergillus가 84s이며 그리고 미동정된 spore수는 524이었다. 옥내와 옥외의 균의 분포를 비교 고찰한 결과 옥내보다 옥외에서 균의 종류가 더 다양하였다 옥내와 옥외에서 발견된 균중 빈도가 많은 네균류의 분포를 보면, Cladosporium, Penicillium, Alternaria, Aspergillus순으로 많이 나타났다. 그 중 Cladosporium, Penicillium, Aspergillus는 옥내에서, Alternaria고는 옥외에서 더 많이 분리 되였다. 옥외지역의 경우 상업지역, 교통지역, 주택지역 순으로 균이 많이 분포 되었고, 옥내에서는 공장지역, 백화점, 목욕탕, 병원지역의 순서로 많이 나타난다. 계절별로 보면 총 코로니수가 여름, 가을에 걸쳐 많았고, 봄과 겨울이 적은 편이었다. Cladosporium, Penicillium, Aspergillus 경우에는 가을에 많이 분포되어 있었으며, Alternaria는 여름에 많이 분리되었다. 그리고 Cladosporium은 계절별 커다란 차이가 나타나나 Penicillium, Alternaria는 계절별 차이가 적고 Aspergillus는 계절별 차이가 거의 없었다. 상업지역, 교통지역, 주택지역 등의 옥외 지역을 계절별로 조사한 결과 이들 세 지역 모두 여름과 가을에 걸쳐 많은 균의 분포를 나타내었다. 공장지역, 백화점, 병원지역 등의 옥내지역에서도 마찬가지로 여름과 가을에 가장 많은 균이 분리되었으나 계절 변화에 큰 영향을 미치지 못하는 목욕탕만은 계절적 차이가 현저하게 나타나지 많았다.

• KIEAE Journal
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• 제15권5호
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• pp.107-112
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• 2015

Purpose: This study desires to investigate an effect of indoor temperature, humidity, and illuminance targeting a planting system of double-skin facade and cavity space adjacent to the outside within a certain period of winter. Through this, the study suggests a basic material about an energy conservation effect of double window system using planting to reduce heating load of a building in winter, so desires to contribute to indoor thermal comfort effect and illuminance correction study of double window and indoor plant. Method: Considering effects such as day and night climatic elements and air conditions in winter, illuminance measurement was conducted through a double-skin facade of space, a subject of the measurement, on the basis of practical residence time of a resident, and this study analyzed characteristics of indoor illuminance about this. The study measured and compared a change of insolation, dry-bulb temperature, and relative humidity at each indoor-outdoor measuring point, so measured and compared characteristics of an indoor temperature effect by elements of double-skin facade and indoor plant. Result: Through this study, the researcher could determine that indoor plant within double window in winter not only blocks solar radiation but also photosynthesizes, so is somewhat disadvantageous to winter thermal comfort reducing heating load. In addition, solar radiation going through interior plays a role to bring down somewhat high humidity to about 50% of reasonable humidity, so plays a direct role of maintenance of comfortable indoor space. Although there are effects such as blocking of solar radiation and temperature reduction, this has a positive influence on humidity control and proper illuminance distribution. The researcher could determine that illuminance, temperature, and humidity by solar radiation penetration for the whole measuring time play a role to supplement indoor environment mutually.

• 한국산림과학회지
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• 제3권1호
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• pp.5-9
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• 1963

1. Creosote in treated wood that exposed in open areas of outdoor is gradually lost by elapse of some period of time. This is the interst and important problem relating to decide the effect on the life extension of creosoted wood. As a general preservative losses occurring in wood treated by oil born preservative such as creosote oil are taken place boy the evaporating and washing activities of the exposed surfaces of wood due to the climatic conditions. Accordingly author intend to inspect differences in retention among species showing after creosoted blocks had been treated by evaporating and washing alternately for a definite time in the laboratory. 2. In this study rail road tie woods of Quercus aliena Blume, Fagus crenata Blume and Fraxinus mandchurica Ruprecht which entered into area for treatment at the plant, locating in Suwon, Korea, were selected to the test species. $2{\times}2{\times}2$ centimeter forty small wood blocks for each species were cut, treated by the mixed solution of equal 50% creosote and heavy oil (hot and cold method), and inspected absorption percents. After evaporation and washing treatments alternately to the intervals of definite time had been accomplished, the losses of creosote were inspected. 3. According to the results Quercus Fagus and Fraxinus are showing the values of 37.9, 87.3 and 59.3% in absorption, and these values were reduced into 28.7, 63.8 and 44.4% respectively by evaporating and washing treatments for a definite time. These indicate that losses of ease absorbing species are greater than difficult one and on the contrary difficult are lesser. However above reduced values are calculated to the 24.3, 26.9 and 25.1% when the absorption percents of each species were assumed as 100% retention respectively. Therefore actual differences of losses among species are lesser than those of absorption percents.

• 한국균학회지
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• 제2권1호
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• pp.21-24
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• 1974

본(本) 시험(試驗)은 우리나라에서 열대(熱帶)및 아열대(亞熱帶) 지방(地方)에서 재배(栽培)되고 있는 풀버섯[Volvariella volvacea(Bull. ex Fr.) Sing.]의 재배(栽培) 가능성(可能性)및 다수확방법(多收穫方法)을 구명(究明)코자 실시(實施)되었다. 1. 우리나라에 있어서 재배적기(栽培適期)는 6월말경(月末頃)부터 8월말(月末)의 2개월(個月) 내외(內外)의 기간(期間)이었다. 2. 볏짚은 5일간(日間) 수침(水浸)한 후 재배사내(栽培舍內)에서 정열(頂熱)($60^{\circ}C$. 6시간(時間))후(後) $55^{\circ}C$ 내외(內外)에서 6일간(日間) 후발효(後醱酵)한 것이 야외퇴적(野外堆積)한 후 후발효(後醱酵)시킨 것보다 증수(增收)되었다. 3. 5일간(日間) 수침(水浸)한 볏짚을 6일간(日間) 후발효(後醱酵)하여 배지(培地)를 만들고 종균접종(種菌接種) 7일(日) 후(後)에 양토(壤土)로서 복토(覆土)하였을 때 볏짚 100kg당 20.49kg으로 가장 높은 수량(收量)을 얻을 수 있었다.