• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2001.11a
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• pp.52-56
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• 2001

Experiments of 2 type on insulating compounds accomplished to change PVC using in URD(Underground) power cable jacketing. one was DB(Dielectric Breakdown) test on the pure base resins and the others were WVT(Water Vapor Transmission) test on the compounds which contained C/B(Carbon Black), anti-oxidant to base resin. a kind of specimens made by pressing to resin of pellet or lump form was HDPE(High Density Polyethylene), MDPE(Medium Density Polyehylene), LDPE(Low Density Polyethylene), LLDPE(Linear Low Density Polyethylene), PVC(Polyvinyl Chloride). As a results of AC DB and WVT test, we saw that strength of Insulation was HDPE> LLDPE = MDP E> LDPE and WVT ratio was HDPE

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.23 no.1
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• pp.9-15
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• 2017

To identify applicability for packaging material of polyvinyl alcohol (PVA)/boric acid (BA) coating solution with highly-enhanced water vapor and oxygen barrier properties, the PET/PVA-BA/OPP multi-layer films were prepared through comma coating and lamination process. The oxygen and water vapor permeabilities, and tensile strength of as-prepared multi-layer films were investigated before and after pressure cooker test (PCT). Although oxygen and water vapor permeabilites, and mechanical properties of PET/PVA-BA/OPP multi-layer films was decreased after PCT, their properties were highly enhanced as increase of BA contents in PVA matrix. This is strongly related with enhanced cross-linking density in PVA-BA layer. In storage test of seasoned-laver, the PET/PVA-BA/OPP multi-layer films were comparatively effective to suppress the increase in peroxide value originating from oxidation of seasoned-laver. Comparing the commercially available PP/Al-metallized PP for seasoned-laver packaging, however, PET/PVA-BA/OPP multi-layer films did not show any advantage in water activity. This is due to higher water vapor permeation properties of as-prepared multi-layer films. Therefore, further studies are required to enhance the water vapor permeation in PET/PVA-BA/OPP multi-layer films.

• Carbon letters
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• v.12 no.4
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• pp.185-193
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• 2011

Carbon nanotubes (CNTs) have developed into one of the most competitively researched nano-materials of this decade because of their structural uniqueness and excellent physical properties such as nanoscale one dimensionality, high aspect ratio, high mechanical strength, thermal conductivity and excellent electrical conductivity. Mass production and structure control of CNTs are key factors for a feasible CNT industry. Water and ethanol vapor enhance the catalytic activity for massive growth of vertically aligned CNTs. A shower system for gas flow improves the growth of vertically aligned single walled CNTs (SWCNTs) by controlling the gas flow direction. Delivery of gases from the top of the nanotubes enables direct and precise supply of carbon source and water vapor to the catalysts. High quality vertically aligned SWCNTs synthesized using plasma enhance the chemical vapor deposition technique on substrate with suitable metal catalyst particles. This review provides an introduction to the concept of the growth of vertically aligned SWCNTs and covers advanced topics on the controlled synthesis of vertically aligned SWCNTs.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 1996.11a
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• pp.50-53
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• 1996

This paper reports the experimental results for the determination of the overall partition coefficient of VOCs in unsaturated soil, A chromatographic method was used for the determination of gaseous partition coefficients to natural soil under various water content conditions. The equilibrium vapor pressure of water over saturated salt solution was used to fix the relative humidity of the air and control the water content of the soil systems. The transport behavior was studied for dichloromethane, trichloroethane and dichlorobenzene pollutants, with log octanol-water partition coefficients(log $K_{ow}$ ) which range from 1.25 to 3.39, or water to soil partitioning which varies by 135 times; water solubility constants which vary by 3 times; and vapor pressures which range from 1 to 362 torr. Water content of the soil had a pronounced effect on the effective partition coefficient(between gas and soil + water stationary phase) as well as on the effective dispersion coefficient.

• Korean Journal of Human Ecology
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• v.10 no.4
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• pp.333-347
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• 2001

The purpose of this study is to find out the washing methods specified on the care labels of vapor-permeable & water-proofed fabrics and to investigate the consumers' real washing methods in their home and their cognition. In this study, the condition of care labels on 35 products was investigated and consumers' washing methods and cognition were surveyed. The subjects were consisted of majoring clothing textiles' female, female student attending in other major and married-women. Data were analyzed SPSS 10.0. The major results were as follows : 1. The care labels of Vapor-permeable & waterproofed fabric products used in this survey followed the rule of KS K that is stated that care labels must include over 3 instructions. It was the most popular type of care labels to organize with washing methods, bleaching methods, weaving methods, drying methods, ironing methods. 2. Most consumers have vapor-permeable & waterproofed fabric products, but their consciousness of this fabric is low. The rate of consumer confirming the care labels was 76.6% but 67.8% of them answered they take care of textile products with their experiences. 3. Consumers' understanding of care instructions on care labels was investigated that most consumers understand domestic care instruction, but they didn't know almost all international one.

• Journal of Environmental Science International
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• v.1 no.2
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• pp.15-23
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• 1992

Development of cumulus is studied by numerically integrating the equation of motion equations of conservation for water vapor mixing ratio, and the thermodynamic energy equuation. We use the terrain-following coordinate system called z'-coordinate system, in which we can easily treat any calculation domain with terrain configuration such as mountains. The model domain of calculation is restricted vertically to 4.Skin and horizontally to 100 km, has a bell-type mountain in the centeral part. Four cases are considered, one in a neutral environment, second in a slightly stable environment, third in a environment decreasing water content with low value of initial water vapor mixing ratio, the fourth in a case with higher vapor gradient. The more the atmosphere is unstable, the more cumulus develops easily and the more water vapors is abundant, the more cumulus develops easily too. More detailed cloud microphysics parameterizations and wet deposition must be conridered to use in air pollutants prediction model.

• Fashion & Textile Research Journal
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• v.6 no.4
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• pp.511-514
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• 2004

We studied on the bleaching properties of silk fabric by vapor type ozone processing using ozone's strong oxidation instead of 28% $H_2O_2$ chemical treatment. When vapor type ozone processing was directly treated to fabrics retaining water to 50~70% pick up ratio, high concentration ozone was generated 14,000ppm(168 mg/h) approximately and finally its bleaching improved. The fabric's bleaching effect was improved because vapor type ozone generated the highest decomposition to oxidation of surface and inter molecules. The experiment revealed that fabric's bleaching was improved by change of the pick-up ratio of vapor type ozone processing. However, tensile strength and elongation were reduced by increase of time, and the time that was assumed as the most optimized time to minimize the reduction of fabric's tensile strength and elongation as well as maximizing the fabric's bleaching was 30 minutes.

• Fashion & Textile Research Journal
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• v.3 no.4
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• pp.362-366
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• 2001

We studied on the softness properties of polyester fabric by vapor type ozone processing using ozone's strong oxidation instead of 25% NaOH chemical treatment. When vapor type ozone processing was directly treated to fabrics retaining water to 40% pick up ratio, high concentration ozone was generated oxidation of 3~4% approximately in polyester fabrics and finally its softness improved. The fabric's softness effect was improved because vapor type ozone generated the highest decomposition to oxidation of surface and inter molecules. The experiment revealed that fabric's softness was improved by change of the time of vapor type ozone processing. However, tensile strength and elongation were reduced by increase in time, 60 minute was assumed as the most optimized time to minimize the reduction of fabric's tensile strength and elongation as well as maximizing the fabric's softness.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2002.07a
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• pp.244-247
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• 2002

In order to evaluate the water ingress to URD power cables with the jacketing materials and the cable structures, water vapor transmission (WVT) tests were carried out by the ASTM and the TEPCO's specification. All polyolefin compounds showed the superior water suppression to conventional PVC. Especially, linear polyethylenes have very low WVT. In case of cable structures, Allaminate cables showed the significant water suppression due to the watertight structure. Accordingly, it can be concluded that jacketing material and cable structure play an important role in the water suppression of URD power cables.

• Journal of Korean Society for Atmospheric Environment
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• v.19 no.E4
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• pp.149-155
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• 2003

In this study. the amounts of the total precipitable water (TPW) in both global and regional scale are estimated from the MODIS instrument, which is on-board the EOS satellites, Terra and Aqua. The estimation is made from the five near-infrared spectral bands, using a technique employing ratios of water- vapor absorbing channels centered at 0.905, 0.936, 0.940 ${\mu}{\textrm}{m}$ with atmospheric window channels at 0.865 and 1.240 ${\mu}{\textrm}{m}$. Through analyses of monthly and eight-days mean TPW, one can monitor characteristics of seasonal variations as well as amount and distribution (i.e., water resources) of TPW at both global and local regions. Long-term monitoring of TPW is essential to understand the regional variations of water resources in East Asia.