• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2011년도 춘계 학술논문 발표대회 1부
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• pp.5-6
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• 2011

CO₂ reduction is the most urgent issue the world is facing. So, there should be a measure to reduce the CO₂ emission in construction industry which has more released CO₂ gas than other industries. CO₂ emission of building depend on using energy. Then efficient energy use process working efficiently at CO₂ reduction. Therefore In this study, author find the technical possibility of saving the building energy using the PCM which is able to control heat, storage heat and potential heat. So, it considered that apply to floor heating type which is major heating system of living space in Korea. And evaluate the Using possibility.

• 설비공학논문집
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• 제28권1호
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• pp.15-20
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• 2016

Phase change materials (PCM) are able to store a large amount of latent heat, and can be applied to thermal energy storage systems. In a PCM, it takes a long time to store heat in the storage system because of the low thermal conductivity. In this study, a finned-tube-in-tank heat exchanger was applied to a PCM thermal energy storage system to increase heat transfer efficiency. The effects of geometric and operating parameters were investigated, and the results were compared with those of the tube-in-tank heat exchanger. The finned-tube-in-tank heat exchanger showed higher heat transfer effectiveness than the tube-in-tank heat exchanger. The heat exchange effectiveness of the storage tank was determined as a function of the average NTU.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2005년도 하계학술대회 논문집 Vol.6
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• pp.15-16
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• 2005

Chalcogenide phase change memory has high performance to be next generation memory, because it is a nonvolatile memory processing high programming speed, low programming voltage, high sensing margin, low consumption and long cycle duration. We have developed a new material of PRAM with $Ge_1Se_1Te_2$. This material has been propose to solve the high energy consumption and high programming current. We have investigated the phase transition behaviors in function of various process factor including contact size, cell size, and annealing time. As a result, we have observed that programming voltage and writing current of $Ge_1Se_1Te_2$ are more improved than $Ge_2Sb_2Te_5$ material.

• 한국건축시공학회지
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• 제12권4호
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• pp.369-376
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• 2012

본 연구에서는 초기재령에 있어 매스부재를 고려한 고강도콘크리트에 대해 수화발열상승속도를 저감시키기 위한 방안의 일환으로 열흡수성능이 있는 상전이물질을 사용하였다. 또한 수화발열상승속도의 조절에 의한 고강도콘크리트의 자기수축 특성 변화를 분석하고자 하였다. 그 결과, 상전이물질은 시멘트 수화반응을 촉진함으로서 초기재령에 빠른 응결시간과 높은 압축강도 발현을 나타냈다. 또한 수화열 및 수화발열상승속도를 저감시키고, 자기수축량을 감소시키는 결과를 나타내었다. 이를 통해 초기재령의 수화발열상승 속도의 조절에 의해 자기수축량의 저감이 가능하다고 판단된다.

• 한국태양에너지학회 논문집
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• 제33권1호
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• pp.73-78
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• 2013

Hexadecane and exfoliated graphite nanoplate (xGnP)composite was prepared as a shape-stabilized phase change material (SSPCM) in a vacuum to develope thermal energy storage. The Hexadecane as an organic phase change material (PCM) is very stable against phase separation of PCM and has a melting point at $18^{\circ}C$ that is under the thermally comfortable temperature range in buildings. The xGnP is a porous carbon nanotube material with high thermal conductivity. Scanning electron microscope (SEM) and Fourier transformation infrared spectrophotometer (FT-IR)were used to confirm the chemical and physical stability of Hexadecane/xGnP SSPCM. In addition, thermal properties were determined by Deferential scanning calorimeter(DSC) and Thermogravimetric analysis (TGA). The specific heat of Hexadecane/xGnPSSPCM was $10.0J/g{\cdot}K$ at $21.8^{\circ}C$. The melting temperature range of melting and freezing were found to be $16-25^{\circ}C$ and $17-12^{\circ}C$. At this time, the laten heats of melting and freezing were 96.4J/g and 94.8J/g. The Hexadecane was impregnated into xGnP as much about 48.8% of Hexadecane/xGnP SSPCM's mass fraction.

• 공업화학
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• 제21권5호
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• pp.570-574
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• 2010

기존 단열재의 주된 기능은 단지 열전달을 차단하는 기능과 건물로부터 열손실을 줄여주는 기능만을 수행했다. 반면, 축열재는 특정온도 범위 내에서 열에너지를 저장 또는 방출함으로써 건물에너지 사용량을 절감할 수 있다. 축열 건자재는 실내 공기온도 변화주기를 효과적으로 조절하여 일정하게 온도를 유지시킬 수 있다. 결과적으로 냉난방시스템 기능을 효율적으로 향상시킬 수 있다. 본 연구는 건축자재로 많이 이용되고 있는 석고보드에 상변화잠열물질을 축열재로 첨가하여 그 물성과 열환경 특성을 파악하였다. 또한 축열 건자재를 활용할 때 발생가능한 문제점을 확인하였다. 마지막으로 TVOC와 HCHO 함량 분석으로부터 오염물질의 배출가능성을 조사하여 축열 건자재의 환경 친화도를 검토하였다.

• 대한설비공학회:학술대회논문집
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• 대한설비공학회 2006년도 하계학술발표대회 논문집
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• pp.122-125
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• 2006

This paper deals with the Ondol, Korean under-floor heating system using latent heat storage materials. It has been recognized that the heating system using the latent heat storage materials are economically efficient and comfortable. For the comparison and analysis to the data of the existing experiment, a repetitive experiment makes sure the ability of Ondol panel.

• Fibers and Polymers
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• 제7권1호
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• pp.12-19
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• 2006

For thermal adaptable fabrics, the polyurethane-urea microcapsules containing phase-change materials (PCMs: hexadecane, octadecane and eicosane) were successfully synthesized by interfacial polycondensation using 2,4-toluene diisocyanate (TDI)/poly(ethylene glycol) (PEG400)/ethylene diamine (EDA) as shell monomers and nonionic surfactant NP-12 in an emulsion system under stirring rates of $3,000{\sim}13,000$ rpm. The mean particle size of microcapsule decreased significantly with increasing the stirring rate up to 11,000 rpm, and then leveled off. The mean particle size increased with increasing the content and molecular weight (eicosane > octadecane > hexadecane) of PCMs at the same stirring rate. The mean particle sizes of microcapsules were found to decrease with increasing the NP-12 content up to 1.5 wt%, and thereafter increased a little. It was found that the melting temperature ($T_m$) and crystallization temperature ($T_c$) of three kinds of encapsulated PCMs and their enthalpy changes (${\Delta}H_m,{\Delta}H_c$) increased with increasing PCM contents. The encapsulation efficiencies (Ee) of hexadecane microcapsule linearly increased with increasing the content of hexadecane. It was found that the stable microcapsule containing 50 wt% of hexadecane could be obtained in this study. However, Ee of octadecane and eicosane microcapsules increased with increasing PCM's contents up to 40 wt%, and then decreased a little. By considering the encapsulation efficiency, it was found that the maximum/optimum contents of octadecane and eicosane microcapsules were about 40 wt%. By the dynamic thermal performance test, it was found that the maximum buffering levels of Nylon fabrics coated with hexadecane, octadecane, and eicosane microcapsules were about $-2.4/+2.9^{\circ}C,\;-3.6/+3.6^{\circ}C\;and\;-4.0/+4.7^{\circ}C$, respectively.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2001년도 춘계학술대회논문집D
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• pp.226-231
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• 2001

The purpose of this paper is to propose the experimental method of thermal properties of Phase Change Materials (PCMs) by using T-history method. As far, in order to measure the heat of fusion and specific heat of PCMs, conventional thermal analysis methods such as DSC and DTA have been used. Because these methods test very small samples, thermal properties of samples are usually different from those of materials consisting of several components. For these reasons, T-history method, the simple measurement method of the heat of fusion and specific heat of PCMs have been performed. In this paper, we investigated the thermal properties of low temperature PCMs(below $0^{\circ}C$) under the charging process by using T-history method. The results are compared to those of DSC method. The T-history method will be useful for selection of the best PCM from lots of candidates and development of new PCMs.

• 한국섬유공학회:학술대회논문집
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• 한국섬유공학회 2003년도 봄 학술발표회 논문집
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• pp.287-288
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• 2003

Polyurethane(PU) materials have been generally used in the automobile, paint, furniture, adhesive, and textile industries. The use of Waterborne PU was motivated form the environmental point of view, i.e. reduction of solvent emissions into the atmosphere(volatile organic compounds, VOC)[1]. Generally speaking, phase change materials (PCM) have the capability of absorbing or releasing thermal energy to reduce or eliminate heat transfer at the temperature range of the particular temperature stabilizing material[2]. (omitted)