• 한국의류학회지
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• 제19권1호
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• pp.36-50
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• 1995

The purpose of this study was 1) to estimate the improvement of thermal storage/release and moisture transport properties of PEG-treated acrylic athletic socks and suggest the optimum add-on for PEG treatment, 2) to investigate wear performance of untreated cocks and two kinds of socks treated with PEG of minimum and optimum add-on respectively, and 3) to consider the effect of thermal storage/release and moisture transport properties of PEG- treated socks on the wear performance and the subjective comfort zone. Thermal activities of specimens treated by PDC were evaluated on a DSC by measuring the heat of fusion on heating and the heat of crystallization on cooling. Moisture regain, absorption speed, wickability, water retenti on value, and water-vapor permeability were measured. In the wear trials that the subjects performed a subsequent exercise protocol wearing three differently treated socks in a conditioned environment ($14\pm2^{\circ}C$, 65$\pm$2% R.H.), microclimate temperature and humidity, and subjective wear sensations including thermal sensation, wettedness, softness, fit, and overall comfort were obtained. PEC-treated specimens with more than 20% add-on showed thermal storage on heating and thermal release on cooling by a DSC and the heat contents of treated ones were generally proportional to the add-ons. Moisture transport properties were highly improved after PEG treatment and increased rapidly with increasing add-on. The tendencies were, however, relaxed above 50% add-on and the treated knits were much stiffer above that add-on. In the wear trials of untreated, PEG add-on 20%, and 50% acrylic socks, the changes of microclimate temperature of 50% socks were significantly less than that of 20% socks. PEG add-on 50% socks showed significantly less changes of microclimate humidity than other two kinds of socks. Three kinds of socks showed significant differences in overall comfort and add-on 50% socks were accepted more comfortable than other two kinds of socks. Comfort zone of foot was extended after PEG treatment on socks and it implied that the subjects wearing PEG- treated socks felt comfortable in wider ranges of microclimate temperature and humidity.

• 한국염색가공학회:학술대회논문집
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• 한국염색가공학회 2009년도 학술발표대회
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• pp.120-121
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• 2009

We prepared polymer-PCM gels such as prepared frozen gel from polypropylene and n-Paraffin for thermal storage and release materials, their basic properties and possible applications especially in latent heat storage. The preparation methods are used to melting method and absorption method respectively. The composition and properties of prepared frozen gels from polypropylene and n-Paraffin were observed by DSC, FT-IR spectra, ARES and Elemental analysis. We can prepare frozen gels in different temperature for latent heat storage materials as controlling composition of phase change material as well as using different incorporating phase change materials. These frozen gels can be used to latent heat storage materials for several applications.

• 설비공학논문집
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• 제16권1호
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• pp.34-41
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• 2004

The chemical heat pump based on the Dehydration/Hydration process with a MgO/$H_2O$ system has been researched. The reactor bed could be expected to store the heat around 200∼37$0^{\circ}C$ by the dehydration reaction and to release the heat around 100∼16$0^{\circ}C$ by the hydration reaction under the heat amplification mode operation. The heat output rate of the heat pump system was evaluated using the experimentally determined parameters. The results show that 6∼50 W/kg of heat output and 0.5∼0.8 of heat recovery ratio are attainable. The heat pump will be applicable for a load leveling in a co-generation system by chemical storage of surplus heat at low heat demand and by supplying heat in the peak load period.

• 한국태양에너지학회 논문집
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• 제27권3호
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• pp.63-69
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• 2007

The heat transfer characteristics of inorganic salt for high temperature heat storage material of solar power system were examined. The inorganic salts employed in this study was a mixture of $NaNO_3$ and $KNO_3$ and the operating temperature range was determined by measuring the melting temperature with DSC and by measuring the thermal decomposition temperature with TGA. The heat transfer characteristics was qualitatively obtained in terms of temperature profiles of salt in the tanks during the heat storage and heat release process as a function of steam flow rates, steam inlet temperature and the inlet position of steam. The effects of steam flow rates and inlet temperature of steam were experimentally determined and the effect of natural convection was observed due to significant density difference with temperature.

• 한국수소및신에너지학회논문집
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• 제13권1호
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• pp.90-99
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• 2002

In order to utilize hydrogen energy in a large-scale in the future, development of effective hydrogen storage method is essentially required as well as that of efficient hydrogen production method. The hydrogen storage method using metal hydrides has been holding the spotlight as a safer and higher-density hydrogen storage method than conventional hydrogen storage methods such as liquid hydrogen or compressed hydrogen storage method. However when metals react with hydrogen to store hydrogen as metal hydrides, they undergo exothermic reactions, while metal hydrides evolve hydrogen by endothermic reaction. Therefore, hydrogen storage tank should have such structure that it can absorb or release reaction heat rapidly and efficiently. In this study, a review on the improvement of the heat release and absorption structure in the hydrogen storage tank was conducted, and as a result, a new type of hydrogen storage tank with the structure of vertical-type wall was designed and manufactured. Experimental results showed that this new type of tank could be used as an efficient hydrogen storage tank because its structure is simpler and manufacture is easier than cup-type hydrogen storage tank with the structure of packed horizontal cup.

• 태양에너지
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• 제14권2호
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• pp.91-101
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• 1994

[ $Ca(OH)_2/CaO$ ]계 가역반응 싸이클을 이용하는 화학축열에서 열전도도가 낮은 고체입자 충전층의 전열성능을 개선하여 축열장치의 효율을 높이고자 한다. 본 연구에서는 반응기내의 CaO 입자 충전층의 전열성능 향상을 도모하기 위해 반응기 속에 구리판으로 된 전열핀을 설치하고 수화발열 반응시의 방열특성을 조사 하였다. 이 때 반응조건의 변화에 따른 반응층내의 온도 분포를 조사하고 전열촉진 효과에 대해 검토하였다. 그 결과 구리판 전열핀의 방열촉진 효과로 인하여 수화발열반응의 방열시간이 전열핀을 사용하지 않은 때보다 1/2 이상 단축되었으며, 방열시간은 전열핀의 매수에 가장 많은 영향을 받았다.

• 대한기계학회논문집B
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• 제25권5호
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• pp.653-659
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• 2001

This paper is concerned with the development of a new method for making and separating ice in-water and saving floated ice by installing an evaporation panel in an ice storage tank. The new method shows very good heat transfer efficiency than that of the convectional method. It is because the evaporation panel is directly contacted with water in the storage tank. The experiments were performed by varying inlet and outlet refrigerant temperatures of its evaporator. From the experimental results, the operating characteristics of in-water harvest-type ice storage system were investigated by measuring temperature and pressure at each point of the ice storage system and power required to operating compressor respect to the changes of the inlet and outlet refrigerant temperature of evaporator. It can be think that defrost frequency decreased and heavy ice created as the refrigerant temperature of evaporator outlet and defrost setting temperature is low so gotten result can effect to release efficiency. Also, consumption power, condensing heat quantity, refrigerating capacity and performance efficiency decreased as time goes by. Therefore, these results provide the basic data for system optimization, performance improvement and the possibility of application to other fields.

• 한국에너지공학회:학술대회논문집
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• 한국에너지공학회 2010년도 춘계학술 발표회
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• pp.104-107
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• 2010

• 한국의류학회지
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• 제21권6호
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• pp.1041-1050
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• 1997

This study was carried out to improve the thermal insulation properties of wool and wool- like fabrics by treating the fabrics with polyethylene glycol, to evaluate the fabric hand of PEG treated wool and wool-like fabrics and to grade up the fabric hand of the treated fabrics by treating with softening agents. Wool and wool-like fabrics were treated with high molecular PEG-8,000 by PDC. The thermal release/storage properties were measured on a DSC. Hand of specimens were evaluated by KES-FB system. The results were as follows; 1. PEG-treated fabrics showed thermal storage and thermal release properties by DSC and the heat contents were generally proportional to the add-ons. 2. PEG-treated fabrics showed higher Koshi and lower Numeri and Sofutosa values due to lower tensile energy and recovery and higher bending rigidity and shear stiffness as the add- ons increased. 3. PEG-treated fabrics showed much lower bending rigidity after softening agents treatment.

• 설비공학논문집
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• 제1권1호
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• pp.9-20
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• 1989

This paper presents an analysis to predict thermal behaviors of water in ice storage tank during the coldness release process. To deal with complicated transient phenomena due to ice-water phase change and the density inversion, a theoretical model which consists of initial perfectly mixed, stratified and thermal diffusion state was introduced and a criterion on the growth of thermal boundary layer was developed. The analysis includes considerations on the type of ice-making heat exchanger, refrigerator on/off and tank arrangement. Also, discussions on the various parameters and operating conditions which have influence on the performance of the system were made. Finally, simulated results were shown, which agreed with experiments in trends reasonably.