• Proceedings of the Korea Association of Crystal Growth Conference
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• 1997.06a
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• pp.125-129
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• 1997

The effects of the moisture and thermal annealing on CLBO crystal have been investigated. CLBO has hydrated at high humidity condition, resulting in 5B$_2$O$_3$$.$Cs$_2$O$.$8H$_2$O. The surface hydration seems to induce the cracking and the refractive index change in CLBO. The thermal annealing is effective to restore the changed index.

• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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• 1999.06a
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• pp.7-13
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• 1999

An experimental study was performed to discover the effect of silver coating on the frictional behavior of SM45C steel at sliding surfaces. Pure silver was coated the SM45C disk surfaces by a thermal evaporation method. Experiments using a pin-on-disk test-rig was performed under dry air and various humidity conditions. Friction coefficients increased to a high and unstable value after failure of coating, and friction coefficients increased with increasing the thickness of silver coated layer. But optimum coating thickness was not observed.

• Journal of Environmental Science International
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• v.8 no.4
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• pp.423-429
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• 1999

This study was performed to investigate the fluid flow characteristics, the temperature distribution, humidity and PMV(Predicted Mean Vote of thermal sensation) distributions of the 3-dimensional room with side wall exhaust. The finite volume method and turbulence k-$\varepsilon$ models with the SIMPLE computational algorithm are used. As the results of the three dimensional simulations, the region of exceeding Y=1.5m was high temperature and humidity. The inlet velocity and temperature were influenced to the floor strongly, and the room PMV was about -1.0 except the inlets.

• Tribology and Lubricants
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• v.14 no.3
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• pp.1-6
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• 1998

An experimental study was performed to discover the effect of environmental conditions on the rolling resistance behavior of pure silver and lead coated 52100 bearing steel. Pure silver and lead coatings were produced by a thermal evaporation coating method. Experiments using a thrust ball bearing-typed rolling test-rig were performed under vacuum, dry air and controlled humidity conditions. Results showed that agglomeration of particles were suppressed in vacuum environment and resulted in low and stable rolling resistance by shakedown phenomena. Also, humidity related closely to the agglomeration of particles and the rolling resistance after the failure of coated layer.

• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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• 1998.04a
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• pp.47-54
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• 1998

An experimental study was performed to discover the effect of environmental conditions on the rolling resistance behavior of pure silver and lead coated 52100 bearing steel. Pure silver and lead coating were produced by a thermal evaporation coating method. Experiments using a thrust ball bearing-typed rolling test-rig were performed under vacuum, dry air and controlled humidity conditions. Results showed that agglomeration of particles were prevented in vacuum environment and as it showed low and stable rolling resistance by shakedown phenomena. Also, humidity relates closely to the agglomeration of particles and increased the rolling resistance after the failure of coated layer.

• Architectural research
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• v.14 no.4
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• pp.153-161
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• 2012

This paper presents an integrated procedure to predict the temperature and moisture distributions in hardening concrete considering the effects of temperature and aging. The degree of hydration is employed as a fundamental parameter to evaluate hydro-thermal-mechanical properties of hardening concrete. The temperature history and temperature distribution in hardening concrete is evaluated by combining cement hydration model with three-dimensional finite element thermal analysis. On the other hand, the influences of both self-desiccation and moisture diffusion on variation of relative humidity are considered. The self-desiccation is evaluated by using a semi-empirical expression with desorption isotherm and degree of hydration. The moisture diffusivity is expressed as a function of degree of hydration and current relative humidity. The proposed procedure is verified with experimental results and can be used to evaluate the early-age crack of hardening concrete.

• Journal of the Korean Society of Clothing and Textiles
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• v.25 no.1
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• pp.83-90
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• 2001

Cooling garments are being considered for reducing heat strain in hot environment. We evaluated the effectiveness of ice gel-based cooling vest in hot environment both resting and exercising. Four male subjects were exposed to heat(4$0^{\circ}C$, 50%RH) with vest or without it. The results were as follows; In case of the trial wearing ice gel-based cooling vest, total body weight loss, and local sweat volume were less than those without it. Mean skin temperature, rectal temperature, pulse, energy expenditure, temperature of inside clothes, and humidity of inside also were lower than those without cooling vest. By subjective thermal sensation, subjective humidity sensation, and thermal comfort sensation, it was proved that non-wearing vest decreased comfort than wearing that. These results suggested that wearing ice gel-based cooling vest reduced human heat strain in hot environment both resting and exercising.

• 한국신재생에너지학회:학술대회논문집
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• 2008.10a
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• pp.40-43
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• 2008

High temperature polymer electrolyte membranes incorporating ionic liquids (ILs) in different polymers such as commercial fluorinated polymers, sulfonated polymers and recasted nafion have been developed. ILs based on imidazolium cation and different anions possess high ionic conductivity and good thermal stability and have been used in the present study. The membranes containing IL show conductivity ${\sim}10^{-2}S\;cm^{-1}$ above $100^{\circ}C$ under anhydrous conditions and are thermally stable up to $250-300^{\circ}C$. IL acts as a conducting medium in these electrolytes and plays the same role as played by water in fully hydrated nafion membranes. Due to high conductivity and good thermal stability, these membranes are promising materials for PEFCs at higher temperatures under anhydrous conditions.

• Proceedings of the KIEE Conference
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• 2006.07b
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• pp.1151-1152
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• 2006

In this paper, we examined 10 domestic samples of three different model using thermal, humidity freeze, thermal-endurance and damp heat test under IEC61215 photovoltaic module environmental endurance test condition. Three was almost no changes on power generation. Insulation resistance capacity was much higher than judgement standard but, showed unstable results depending on environmental test items. On external appearance test, there were two models which showed bubble, humidity penetration, seal melted frame phenomenon. From this results, the degree of aging under the external environment is a main cause that shortens photovoltaic module life time. So it is considered that the efforts for finding optimum condition of manufacturing process should be needed.

• Journal of the Korea Furniture Society
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• v.15 no.1
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• pp.9-16
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• 2004

Five type boxes manufactured from cement(A), wood panel(B), charcoal-packed wood panel(C), plywood panel(D) and charcoal-packed plywood panel(E) were prepared. Relationship of preservation characteristic of strawberry and relative humidity, and properties of thermal and sound insulations in the boxes were examined. During the experimental duration, relative humidity in the cement box was highest and lowest in the charcoal-packed wood panel box. Weight loss of strawberry was greatest in charcoal-packed wood panel box and very little in cement box. In the boxes with charcoal-packed wood panel box and very little in cement box. In the boxes with charcoal, strawberry was preserved for 10 days without getting mold, but in cement box it was covered with mold in 3 days. The charcoal-packed boxes showed higher thermal insulation property than the cement box. There were no significant differences in the property of sound insulation among the 5 type boxes. Consequently, it is suggested that charcoal-packed wood panels can be used for a better ecomaterial.