• KIEAE Journal
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• 제12권4호
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• pp.89-95
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• 2012

At present, many countries are trying to reduce green gas emissions to mitigate the effects of these gases on climate change. Year after year, there have been efforts to cut energy use for heating and cooling. Heating and cooling systems, common in all forms of housing, are increasing due to the constant supply of new housing resulting from improvements in economic growth and the quality of life. Thus, studies related to the design of cooling and heating systems to improve energy efficiency are expanding. Among the new designs, radiant floor cooling and heating systems which use capillary tubes are becoming viable means of reducing energy use. Radiant floor cooling and heating systems which use capillary tubes are creative and sustainable systems in which cool and hot water is circulated into capillary tube which has small diameter. In this study, the cooling and heating performance of this type of capillary tube system is investigated in an experimental study and a simulation using TRNSYS. The results of the experimental study show that under a peak load, a capillary tube radiant floor cooling system using geothermal energy can achieve desired indoor temperature without an additional heat source. The set room air temperature is maintained while the floor surface temperature, PMV and PPD remain within the comfort range. Also, this system is more economic than a packaged air conditioner system due to its higher COP. The results of the simulation show that the capillary tube radiant floor heating system maintains set temperature more stable than a PB pipe radiant floor heating system due to its lower supply temperature of hot water. In terms of energy consumption, the capillary tube radiant floor heating system is more efficient than the PB pipe radiant floor heating system.

• 대한환경공학회지
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• 제31권9호
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• pp.811-816
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• 2009

최근 문화재의 훼손을 미연에 방지하기 위하여 보존환경 및 훼손영향에 대한 연구가 중요하게 대두되고 있다. 본 연구에서는 국내 박물관 3곳의 환경 중 동산문화재의 보존환경과 관련된 전시실, 전시케이스, 수장고에서 온 습도, 산류, 암모니아, 환원황화합물, 알데히드류를 조사하여 주요 영향 인자를 확인하고자 하였다. 조사 결과 온 습도, 총휘발성유기화합물, 아세트 알데히드는 빈번히 국 내외의 박물관 보존환경 기준 및 실내공기질 기준을 초과하였고, 포름알데히드, 염소, 암모니아는 간헐적으로 기준을 초과하는 특성을 보였다. 빈번히 기준을 초과한 온도, 습도, 총휘발성유기화합물, 아세트알데히드, 동산문화재의 주요 영향인자로써 동산문화재의 효과적인 보존 및 관리를 위해서 이들 인자는 적절한 제어가 필요함을 확인하였다.

• 한국산학기술학회논문지
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• 제16권3호
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• pp.1600-1604
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• 2015

현대 주택이 고기밀 고단열로 건축되기 때문에 에너지 절감의 이점이 있는 반면 오염된 공기로 인한 많은 부작용이 발생하고 있다. 이런 부작용을 해결하기 위해 환기장치를 사용하여 실내 공기 환경을 개선하고 있다. 본 연구에서는 폐열회수 환기장치의 일종인 히트파이프를 사용하여 작동유체 충진량 및 환기량에 따른 히트파이프의 환기성능을 시험적으로 평가하였다. 본 연구에서 사용된 히트 파이프는 환기장치에 적용이 가능하도록 분리형으로 제작되었다. 작동유체는 R22이고 유체의 충진량은 40~55(%vol.)로 5(%vol.) 단위로 충진 하였다. 환기량은 전면풍속을 기준으로 0.3~1.5m/s로 0.3 m/s 간격으로 바꿔 가며 측정하였다. 시험결과 최대 효율을 가지는 냉매 충진량이 환기량에 따라 다름을 알 수 있었고, 실험 결과 분석을 통하여 분리형 히트파이프의 환기량에 따른 최적 냉매 충진량을 찾을 수 있었다.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2003년도 하계학술대회 논문집 Vol.4 No.2
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• pp.818-821
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• 2003

Ozonic use of sterilization and heat treatment of raw material to extend the conservation period of food recently is increased by hard vegetable or microorganism sterilization purpose of fruit. If ozone can create as is easy comparatively because do air or oxygen by raw material and schedule period passes, there is advantage that do not leave the second contaminant because being gotten restored by oxygen. Also, because the effect is big to decolorization beside sterilization effect about microorganism, deodorization, disjointing of venomousness hazardous substance, food save, indoor air purge, good hand processing, hydrospace agricultural chemicals processing etc. the use extent is wide. This research ran parallel a sterilization experiment of E.coli colitis germs by ozone that manufacture ozonizer that use doped diamond maund electrode (BDD) by boron and searched special quality electrochemistry enemy of the ozonizer and is created. E.coli. After cultivate E.coli colitis germs during 37C 1 day is LB ship, after do ozonation, was sterilized more than 90% by ozone as result that examine sterilizing power by substance microscope and could confirm excellency of diamond electrode.

• Journal of Advanced Marine Engineering and Technology
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• 제36권4호
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• pp.445-450
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• 2012

가정과 같이 제한된 공간에서는 공조기의 온습도 조절이 어려워 질 수 있다. 최근에 들어서 사람들의 온습도에 대한 감성이 민감해 짐에 따라 실내 공기질에 대한 중요성이 부각되고 있다. 실내 공기질과 에너지 절약 사이의 모순을 해결 할 수 있는 방법으로 환기열회수장치를 제시하고 이러한 환기열회수 장치에 열전소자를 적용하여 온도 효율을 비교하고 시스템 능력을 검증해 보았다. 온도효율을 향상시키는데 전도성 가이드 베인과 단일 모터, 열전소자가 실험되었다. 단일 모터 사용시 23W를 절약 할 수 있었고 250 CMH의 능력을 가지는 개발된 시스템에서 통상적인 시스템과 비교해 냉방 주기 및 난방 주기에서 각각 4.01% 와 2.98%의 개선이 있었다.

• Journal of the Korean Wood Science and Technology
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• 제42권2호
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• pp.163-171
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• 2014

Environmental issues about indoor air quality have been increased and focused on volatile organic compounds (VOCs) caused cancer, asthma, and skin disease. Reducing VOCs has been attempted in many different methods such as using environmentally friendly materials and air cleaner or purifier. Charcoal is well known material for absorbing VOCs. Therefore, carbonized board from medium density fiberboard has been developed. We assumed that the source of carbonized boards can be any type of wood-based panels. In this study, carbonized boards were manufactured from oriented strand board (OSB) at 400, 600, 800, and $1000^{\circ}C$. Each carbonized OSB (c-OSB) was evaluated and determined physiomechanical characteristics such as exterior defects, dimensional shrinkage, modulus of elasticity, and bending strength. No external defects were observed on c-OSBs at all carbonizing conditions. As carbonizing temperature increased, less porosity between carbonized wood fibers was observed by SEM analysis. The higher rate of dimensional shrinkage was observed on c-OSB at $1000^{\circ}C$ (66%) than c-OSB at 400, 600, and $800^{\circ}C$ (47%, 58%, and 63%, respectively). The densities of c-OSBs were lower than original OSB, but there was no significant different among the c-OSBs. The bending strength of c-OSB increased 1.58 MPa (c-OSB at $400^{\circ}C$) to 8.03 MPa (c-OSB at $1000^{\circ}C$) as carbonization temperature increased. Carbonization temperature above $800^{\circ}C$ yielded higher bonding strength than that of gypsum board (4.6 MPa). In conclusion, c-OSB may be used in sealing and wall for decorating purpose without additional artwork compare to c-MDF which has smooth surface.

• 한국산업보건학회지
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• 제28권2호
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• pp.151-157
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• 2018

Objectives: This study was conducted in order to evaluate $PM_{10}$ concentrations at eight highway tollgate booths from July to September 2017. Methods: A total of 16 samples were collected from eight toll booths. Each $PM_{10}$ sample was collected using a 37 mm PTFE filter attached to a Personal Environment Monitor. Results: The geometric mean concentrations of $PM_{10}$ in the toll booths was $83.51{\mu}g/m^3$. The mean $PM_{10}$ concentrations measured on freight roadways were much higher than those of measured on general roadways($102.46{\mu}g/m^3$ and $68.05{\mu}g/m^3$, respectively). $PM_{10}$ was revealed to be higher in the morning($105.59{\mu}g/m^3$) than at dawn or in the afternoon($71.26{\mu}g/m^3$ and $61.22{\mu}g/m^3$, respectively). The mean $PM_{10}$ concentration in toll booths ventilated through an air conditioner was higher than that for those using a window or no ventilation. The rate of exceeding the Ministry of Environment Maintenance Limit($200{\mu}g/m^3$) was 6.25%, and the rate of exceeding the Ministry of Labor Recommended Limit($150{\mu}g/m^3$) was 12.5%. Conclusions: In order to protect the health of toll booth workers exposed to airborne dust, it is necessary to check the exposure level from indoor air quality on a regular basis and to manage it appropriately according to the results.

• 기본간호학회지
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• 제11권1호
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• pp.41-48
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• 2004

Purpose: The purpose of this study was to analyze the colony count of airborne microbes contamination every hour in the Neurosurgical Intensive Care Unit (NSICU) in order to identify the relationship of colony count to person-visits. Method: Data were collected during from 11:00 a.m. September 5 to 11:00 a.m. September 6, 2002. This study used blood agar & nutrient agar and handtally counter (USA) for collection of airborne microbes and number of person-visits. Data was analyzed using the SPSSWIN 10.0 with means, Pearson correlation coefficient, and simple regression. Result: The result of this study are as follows. Total colony count of airborne microbes for 24 hours in the NSICU was 4,609. Total number of person-visits to the NSICU was 15,347. The highest scores fur the total colony count in different areas of the NSICU was the rear door, followed by the preparation room, and the front entrance, while the lowest count was in the isolation rooms. There was a statistically significant relationship between colony count and number of person-visits to the NSICU. The most frequently airborne microbes in the NSICU were Micrococcus, CNS, Staphylococcus Micrococcus, Aureus. Conclusion: These findings indicate that the number of person-visits in hospitals influences total colony count of airborne microbes. This study contributes to assessment of biological indoor air quality in hospital and in the development of an NSICU care plan.

• 한국입자에어로졸학회지
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• 제13권2호
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• pp.87-95
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• 2017

Radon ($Rn^{222}$) is a radioactive gas and is found at high concentrations underground. Investigations were done in many years specifically on public transportations such as in the subway stations, concourses and platforms for these are located underground areas. This study correlates the $Rn^{222}$ concentrations with the Particulate Matter (PM) concentration for the gas could be attached or trapped inside these particles. It was done on the opening subway tunnel of Miasageori Station going to Mia Station (Line 4) last August 2016. Based on the result, the $Rn^{222}$ were more influenced on the mass ratio (%) of PM present in the air instead of its mass concentration (${\mu}g/m^3$). As the $PM_{10}$ mass ratio increases ($42.32{\pm}1.03%$) during morning rush-hours, radon starts to increase up to $0.97{\pm}0.03pCi/L$. But during the afternoon $Rn^{222}$ concentrations decreased while the composition were stable at $22.96{\pm}3.0%$, $39.04{\pm}0.6%$ and $38.01{\pm}0.3%$ in $PM_1$, $PM_{2.5}$ and $PM_{10}$ respectively. It was then assumed that it could be the composition of the morning hours of the station were influencing the concentration of the radon.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2003년도 추계학술대회 논문집 Vol.16
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• pp.607-610
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• 2003

Ozonic use of sterilization and heat treatment of raw material to extend the conservation period of food recently is increased by hard vegetable or microorganism sterilization purpose of fruit. If ozone can create as is easy comparatively because do air or oxygen by raw material and schedule period passes, there is advantage that do not leave the second contaminant because being gotten restored by oxygen. Also, because the effect is big to decolorization beside disinfection effect about microorganism, deodorization, disjointing of venomousness hazardous substance, food save, Indoor air purge, good hand processing, hydrospace agricultural chemicals processing etc. the use extent is wide. This research ran parallel a sterilization experiment of E.coli colitis germs by ozone that manufacture ozonizer that use doped diamond maund electrode (BDD) by boron and searched special quality electrochemistry enemy of the ozonizer and is created. After cultivate E.coli colitis germs during 37C 1 day is LB ship, after do ozonation, was sterilized more than 90% by ozone as result that examine disinfection effect by substance microscope and could confirm excellency of diamond electrode.