• Proceedings of the KWS Conference
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• 1996.05a
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• pp.133-135
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• 1996

• Journal of the Korea institute for structural maintenance and inspection
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• v.9 no.3
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• pp.203-212
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• 2005

Cellulose insulation is primarily manufactured from recycled newsprint and treated with fire retardants for the fire resistance. Thanks to the fire retardants, it is not combustible and flammable. In addition to that, Its thermal resistance is much better than that of fiberglass or rock wool. It is made from waste paper and easily decayed when it is demolished, and it has small embodied energy. So it is very environment-friendly building material. For broader use of cellulose insulation in buildings in Korea, it is necessary to test its physical performance to compare the results with the requirements on the Korean Building Code. To this end, apparent thermal conductivity (ka) measurements of Korean-made loose-fill cellulose insulations were recently completed using equipment that was built and operated in accordance with ASTM C 518 and the fire resistance was tested in accordance with ASTM C 1485. Korean loose-fill cellulose has thermal conductivity about 5% greater than the corresponding U.S. product at the same density. This is likely due to differences in the recycled material being used. Both spray-applied and loose-fill cellulose insulation lose about 1.5% of their thermal resistivity for $5.5^{\circ}C$ increase in temperature. The fire resistance of cellulose insulation is increased in linear proportion to the increase of the rate of fire retardant. Thanks to the high fire resistance, cellulose insulation can be used as a substitution of Styrofoam or Urethane foam which is combustible. The thermal conductivity of cellulose insulation was $0.037-0.043W/m{\cdot}K$ at the mean specimen temperature from $4-43^{\circ}C$. It corresponds to the thermal resistance of "Na Grade" according to the Korean Building Code. The effect of chemical content on thermal conductivity was negligible for all but the chemical-free specimen which had the highest value for the thermal conductivity over the temperature range tested. The thermal resistance of cellulose insulation is better than that of fiberglass or rock wool, and its fire resistance is higher than that of Styrofoam or Urethane foam. Therefore it can be substituted for those above considering its physical performance. Cellulose insulation is no more expensive than Styrofoam or rock wool, so it is recommended to use it more widely in Korea.

• Journal of the KSME
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• v.26 no.1
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• pp.31-35
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• 1986

물질전달이 포함되는 교환기의 설계목표도 단순열교환기의 경우와 마찬가지로 여러 가지 주어진 제약조건(constraints; 예를들면 교환기의 제원이나 유체유동에 필요한 압력부하등)을 만족시키 면서 전달능력의 단위(number of transfer units, 이하 $N_{tu}$ 로 약함)를 최대로 해 주는데 있다. 그러나 교환장치들의 유형이나 형상에 따라 이같은 동일 목적을 위한 과정은 각양각색 이다. 본장에서는 직접 접촉식 교환기의 많은 종류중 물의 직접증발을 이용한 단열가습장치와 고체건조제 단열제습장치등 두가지의 해석과정을 예시하려고 한다.

• Proceedings of the SAREK Conference
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• 2008.06a
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• pp.869-872
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• 2008

On this study, the Control of Temperature is specified on the view of indoor comfort and building energy consumption. It is estimated by Dynamic heat load simulation which has the factors of insulation method and the soil thickness of the green roof system. The fact that the model which has no insulation has the greatest effect of dropping high temperature and the cooling load decrease is confirmed.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2010.04a
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• pp.758-761
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• 2010

본 연구에서는 원전격납구조물과 같이 고품질의 대형 매스콘크리트의 설계, 시공, 품질예측 및 관리에 필요한 구조물 건전성 평가시스템 구축의 일환으로 수화열 예측 프로그램을 개발하였다. 개발된 수화열 예측 프로그램은 국내에서 생산된 시멘트 및 결합재의 화학조성성분, 분말도와 같은 기초정보 및 배합정보를 입력하여 경시변화에 따른 수화발열량을 계산하는 방식으로서 기존의 연구결과를 바탕으로 개발되었다. 개발된 프로그램은 배합환경조건을 고려하여 초기배합온도 3종류(10, 20, $30^{\circ}C$)로 실험한 단열온도상승 실험 결과와 비교해 보았으며, 좋은 상관성을 나타냄을 확인할 수 있었다.

• Proceedings of the Korean Vacuum Society Conference
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• 2013.08a
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• pp.307.2-307.2
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• 2013

창호를 통해 건축물 내부에 유입되는 태양광, 특히 태양열 유입에 큰 영향을 미치는 적외선 파장대역을 차폐할 수 있는 특성을 갖는 근적외선 반사 또는 흡수용 원천소재 개발하였다. 근적외선 반사는 고 굴절률/저 굴절률 다중 코팅막을 이용하여 상대적으로 에너지가 높은 800~1,300 nm 파장 영역의 근적외선만을 효율적으로 반사시킬 수 있 방식으로 적외선 차단 효율을 개선하였다. 근적외선 흡수용 나노박막 유 무기 복합소재를 기반으로 하여 특정 파장대에서 적외선을 흡수하도록 하여 적외선 차단 효율을 증대시켰다. 본 연구개발의 고단열 유리는 기존에 개발된 저방사 유리의 문제점인 높은 근적외선 투과문제를 해결하기 위한 대체/보완기술로서 이를 이용한 대면적 코팅을 통한 고기능성 복층창호 시스템을 구성하였고, 이에 대한 단열 특성 실험을 실시하였다.

• Proceedings of the Korean Institute of Landscape Architecture Conference
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• 2017.10a
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• pp.147-149
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• 2017

경수 용기재배는 뿌리분의 손상 없이 식재를 할 수 있어 이식 후 활착이 용이하고, 식재시기의 계절적 제약을 적게 받아 부적기 이식 시 하자를 현저히 줄일 수 있다. 용기재배 시 용기 내 토양온도는 토양의 물리화학반응과 식물의 생육 및 물과 양분의 흡수에 영향을 주는 중요한 토양환경요소의 하나이다. 목본성 식물 용기재배의 경우 제한된 근권부의 토양이 외부기온에 의해 불안정할 수 밖에 없다. 재배용기의 유형에 따른 지온의 변화를 측정한 결과 지중재배형의 용기가 단열성능이 큰 것으로 나타났다. 지상재배 방식의 용기 중에서는 Bag in Pot-루트 스커트 형의 용기가 단열성능이 큰 것으로 나타났으며, 이는 지중재배방식의 용기와 유사한 용기 내 지온 안정화 정도를 보이는 것으로 나타났다. 향후 후속 연구에서는 본 연구를 토대로 디자인 개발된 용기의 시제품을 제작하여 테스트하고, 재배농가에 적용가능성을 검토하고자 한다.

• Journal of Bio-Environment Control
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• v.4 no.1
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• pp.59-67
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• 1995

This study was conducted to develope the automatic insulation system which control inside temperature of the greenhouse. For this purpose, the double- wall greenhouse and system which could automatically supply and discharge styrene pellets were constructed and abrasion of the pellets, blower ability, insulating property, transmittance and shading effect were analyzed by the experiments. The results obtained from this study can be summarized as follows : 1. It took an hour and fifteen minutes to supply and discharge about 2㎥ pellets in the experimental greenhouse. However, it is possible to reduce the operation time by proper selection of the blower and exhaust port, and by proper control of the supply and return pipe. 2. It was founded that the indirect delivery way was more profitable than the direct one in the supply and return of pellets. 3. When the transmittance was measured between 10 a.m. and 3 p.m., the average light transmissivity rate was 67%. 4. In winter nighttime, the inside temperature of the double- wall greenhouse with out the pellets was higher than the outside temperature by 3.4$^{\circ}C$ on an average. However, the inside temperature of the double - wall greenhouse with insulated area 73% was higher than the outside by one 6.6$^{\circ}C$ on an average, and the inside temperature of the greenhouse with insulated area 100% was higher than outside one by 13.5$^{\circ}C$ on an average. Therefore, it was proved that the insulating ability of the double - wall greenhouse in nighttime was excellent. 5. When the outside temperature was 36.9$^{\circ}C$ on an average, the inside temperature of the double- wail greenhouse with insulated area 100% was 3$0^{\circ}C$ on an average. As the inside temperature was lower than the outside one by 7$^{\circ}C$ on an average, we could know that the shading effects of the double- wall greenhouse were excellent in summer daytime.

• Journal of the Korean Institute of Gas
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• v.24 no.4
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• pp.56-61
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• 2020

For the hydrogen liquefaction, the large amount of energy is consumed, due to precooling, liquefaction and o-p conversion processes. The aim of this work is to improve the performance of hydrogen liquefaction process by introducing the new energy saving processes, that are the liquid nitrogen precooling process by using LNG cold energy, and the new design of cold box insulation using cold air circulation. The results show that the indirect use of LNG cold energy in precooling process enables not only to get energy saving, but to make safer operation of liquefaction plant. In new cold box, the energy loss of equipments could be reduced by nearly 35%~50% compared to the present perlite insulation, if insulation structure is organised as 3mm steel wall/20cm PUF/5cm air/20cm PUF/equipment. Additionally the equipments installed in cold box can get cooling effect, if the temperature is higher than the temperature of cold air. The application of this results can gives to increase the liquid yield of about 50% substantially in industrial hydrogen liquefaction plant.

• Journal of Advanced Marine Engineering and Technology
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• v.37 no.8
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• pp.843-848
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• 2013

As the LNG demands are growing, the constructions of LNG FPSO (Floating Production Storage and Off-loading) and LNG carriers have been constantly increased, and the various design of storage tank has been tried. This paper propose that the material of inner storage tanks is made of 5~9% Ni steel plate and perlite powder insulation instead of urethane foam block. It needs essentially to obtain the proper design specifications that are the pressure of perlite, the characteristics of resilient blanket as the pressure absorber, optimum thickness of blanket and design pressure of tank wall, etc. to enable the perlite insulation system to LNG carrier, The results show that the design thickness of blanket should be between 1/4 to 1/3 of insulation width and the optimum rate becomes 30%, and the design pressure be applied below 1,500 Pa with blanket thickness.