• 한국추진공학회:학술대회논문집
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• 한국추진공학회 2011년도 제36회 춘계학술대회논문집
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• pp.296-297
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• 2011

본 연구에서는 PTFE 전기절연재의 수명예측을 위해 일련의 열중량 분석시험을 수행하였다. PTFE 시료는 온도상승률을 달리하며 상온에서 $700^{\circ}C$까지 온도를 가하였다. PTFE의 활성화에너지는 일정한 중량감소가 발생할 때의 로그 형태 온도상승률에 대한 변환온도 역수 선도에서 계산하였다. 또한 Toop에 의해 제안된 활성화 에너지와 추정 수명과의 관계식을 이용하면 주어진 운용온도 하에서의 PTFE 수명시간도 예측할 수 있다.

• 한국지열·수열에너지학회논문집
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• 제15권3호
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• pp.1-6
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• 2019

The basalt fiber, which is found to be non-toxic and harmless to the human body, is expected to become a trend for industrial fibers as they have better properties of non-combustion, heat-resistant, soundproof, absorbent, moistureproof, wear-resistant, corrosion resistant, lightweight, and high strength properties. Thus, in this study, we analyzed the chemical compositions of basalt produced at seven sites on Jeju Island for making a high value inorganic insulation material. The results showed that the MgO content of basalt collected from the eastern part of Jeju Island was higher than 7.5 percent, while that of the western region was less than 6 percent.

• 국제학술발표논문집
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• The 4th International Conference on Construction Engineering and Project Management Organized by the University of New South Wales
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• pp.480-486
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• 2011

Conservation of energy and fuel is the trend in smart building design. Radio Frequency Integrated Circuit (RFIC) technology is often used in temperature sensing and signal transmission to manage indoor temperature, but it is rarely applied to the shell of the building. Heat retention and poor insulation in building shells are the largest causes of high energy consumption by indoor air conditioning. Through combining RFIC technology with temperature sensors, this study will develop smart temperature information material that can be embedded in concrete. In addition to accurately evaluating the effectiveness of shell insulation material, the already-designed Building Physiology Information System can monitor long-term temperature changes, leading to smarter building health management.

• 한국산업보건학회지
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• 제4권2호
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• pp.157-167
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• 1994

This study was conducted to analyze the relationship between the types of fiber and its content and the levels of airborne fiber concentrations at eight parking lots where sprayed insulation material was found on the walls and ceilings. Also this study was designed to find the relationship between the levels of airborne fiber concentrations and such variables as air current, humidity, total exhaust volume, surface condition of insulation material and building age. The results obtained were as follows : 1. No significant correlation was found between the levels of airborne tiber concentration and the building age, air current, humidity, total exhaust volume, space and the number of traffics. 2. A significant correlation was found between the levels of airborne fiber concentration and the MMMF content of the insulation material(r=0.7594). However, no significant correlation was found between the levels of airborne fiber concentration and total fiber content of insulation material. 3. The differences of the airborne fiber concentrations among Cateogory 1, 2 and 3 classified by the degrees of surface insulation material maintenance were very significant. 4. Two bulk samples contained 30% crodicolite and 1% anthophylite. The MMMFs, in all parking lots, included mineral wool, cellulose fiber, trace cellulose fiber, trace tiber glass and vermiculite. 5. The mean value and the range of airborne fiber concentrations at 8 parking lots were $0.0239{\pm}0.0095f/cc$ and 0.0054-0.0447 f/cc, respectively. The fiber concentrations of 35 out of 38 samples(92%) were over 0.01 f/cc which is the Environment Administration's recommended asbestos level for the underground space. This study suggests that most of building insulation materials used in Korea, contain MMMF and sometimes asbestos. Currently, MMMF pollution levels may exceed the Environment Administration's recommended level for underground space. It has been found that airborne fiber concentrations increased significantly with MMMF content and with the maintenance condition of surface material. Therefore, it is recommended that a proper management technique should be developed and immediately implemented since the conditions of surface material will be gradually deteriorated due to building age and usage. Since health hazards of the MMMF, similar to those of asbestos, are being gradually acknowledged, a proper management technique which is applicable to control total airborne fiber concentrations, both asbestos and MMMF, be developed and an acceptable indoor air standard be promulgated as early as possible.

• 대한건축학회논문집:구조계
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• 제35권6호
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• pp.121-128
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• 2019

There is a big move to build zero-energy buildings in the form of passive houses that reduce energy waste worldwide. Korea has set a goal of reducing its greenhouse gas emissions by 37% by 2030 through the activation of green buildings, such as strengthening the energy levels of new buildings and improving the energy efficiency of existing buildings. The use of insulation with high insulation performance is one of the key technologies to realize this, and vacuum insulation is the next generation insulation that blocks the energy flow of the building. In this study, we measured the bonding structure of dry and wet processing glass fiber core materials and compared the insulation performance of vacuum insulation panel. In addition, the insulation performance of vacuum insulation panel was measured according to the thickness of the laminated core. It can be confirmed that the lamination structure of the core and the lamination thickness are important factors for the heat insulating performance of the vacuum insulating panel.

• 설비공학논문집
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• 제15권5호
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• pp.372-381
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• 2003

This study aims to find out the optimized insulation thickness of refrigerated warehouse with different envelope structures (RC and PC wall) and insulation materials (urethane and icynene). Each of them is compared according to the thickness of insulation (100, 150, 200 mm/50 or 250 mm) and the temperature of cold storage room (0, -6, -15$^{\circ}C$). As results, it is proved to have the best economical efficiency in life cycle cost when PC wall with thickness of 100 mm (0 and -6$^{\circ}C$) and 150 m (-15$^{\circ}C$) urethane, respectively, are applied.

• 한국대기환경학회지
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• 제24권5호
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• pp.551-561
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• 2008

In order to clarify the impact of anti-heat insulation pavement on the thermal structure of atmospheric boundary layer, field experiments and numerical simulations were carried out. Field experiment with various pavements were also conducted for 24 hours from 09LST 19 June 2007. And numerical experiment mainly focused on the impact of albedo variation, which is strongly associated with thermal characteristics of insulated pavement materials, on the temporal variation of planterly boundary layer. Numerical model used in this study is one dimension model with Planterly Boundary Layer developed by Oregon State University (OSUPBL). Because anti-heat insulation pavement material shows higher albedo value, not only maximum surface temperature but also maximum surface air temperature on anti-heat insulation pavement is lower than that on asphalt. The maximum value of surface temperature only reach on $49.5^{\circ}C$. As results of numerical simulations, surface sensible heat flux and the height of mixing layer are also influenced by the values of albedo. Therefore the characteristics of urban surface material and its impact on atmosphere should be clarified before the urban planning including improvement of urban heat environment and air quality.

• Transactions on Electrical and Electronic Materials
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• 제3권3호
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• pp.34-38
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• 2002

In this paper, efficiency estimation of toxicity fee fire resistance cable experiments was measured smoke density of toxicity free fire resistance polyolefin insulation material and electric field dependence of tree shape in low density polyethylene (LDPE). One of the most serious causes of failure in high-voltage cables, can be an electrical discharge across an internal gab or void in the insulating material. Treeing due to partial discharge is one of the main causes of breakdown in the insulating materials and reduction of the insulation life. Therefore the necessity for establishing a method to diagnose the aging of insulation materials and to predict the breakdown of insulation and research of the fire resistance character has become important. First, we have studied on electric field dependence of tree shape in LDPE about treeing phenomena occurring on the high electrical field. Second, the measurement method is the attenuation quantity of irradiation by smoke accumulating with in a closed chamber due to non-flaming heat decomposition and flaming combustion. A main cause of fire-growth and generating toxic gas when, it bums, should be dealt with great care in life. safety design. The fire gases were occurred carbon monoxide and decomposition than in polyolefin due to incomplete combustion of PVC, which has high content of carbon in chemical compound.

• 한국지반환경공학회 논문집
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• 제20권4호
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• pp.11-16
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• 2019

한랭지역에 설치된 터널의 경우, 저온 및 온도차이로 인하여 터널구조물의 내구성이 저하될 수 있다. 외기온도의 변화에 따른 터널라이닝 및 배면 지반의 온도변화를 감소시키기 위하여 단열성능을 가진 도료(단열재)를 개발하였으며, 단열재를 공용 중인 터널 라이닝에 도포하였다. 단열재는 라이닝의 바닥면으로부터 1.5m 높이까지를 도포하였으며 동절기 기간동안 단열재가 도포된 구간과 도포되지 않은 구간의 라이닝 온도를 측정하여 단열재의 효과를 분석하였다. 라이닝의 온도측정은 위치별, 거리별, 외기 온도가 가장 높을 때, 가장 낮을 때를 중심으로 측정하여 비교하였다. 측정결과 단열재를 도포한 구간의 라이닝 온도저하가 적은 것으로 나타났으며, 최고 및 최저온도간의 온도차이도 적은 것으로 나타나 단열재의 성능을 확인하였다.

• Composites Research
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• 제34권1호
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• pp.57-62
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• 2021

조선해양산업에서 친환경 선박 및 경량화 기자재에 관한 관심이 높아짐에 따라 파이프 등의 기자재에 복합재료를 적용하고 있다. 본 연구에서는 친환경 및 내열/난연 성능을 요구하는 파이프 단열재 커버에 적용하기 위해 친환경 소재인 바잘트 섬유강화 퓨란복합재료(BFC, basalt fiber reinforced furan composite)를 제조하였다. BFC 소재의 낮은 물성을 강화시키기 위해 후경화 조건의 최적화 연구를 수행하였고, BFC 소재의 기계적강도, 내열/난연 특성 강화, 친화경 특성에 대한 실험과 평가를 진행하였다. 최종적으로 연구 결과 조선해양기자재인 파이프 단열재 커버에 BFC 소재의 적용이 가능함을 확인하였다.