• Journal of Korea Soil Environment Society
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• v.3 no.2
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• pp.61-70
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• 1998

This research has been made for influence of forest environmental changes, such as tree-clearcutting affecting to soil chemical and physical properties, on water storage capacity at forest fire land in Keumsan, Chungnam. The analyzed factors were bulk density, porosity, field moisture saturated hydraulic conductivity air permeability and organic matter content, Field moisture saturated hydraulic conductivity and air permeability at uncutting sites were higher than those at clearcutting sites, especially the most differences were appeared at lower slope. After 2 years passed since forest fire, the most changeable parts of soil characteristics were 5-l5cm depth below soil surface. Total Porosity, coarse pore and fine pore at uncutting sites were higher than those at clearcutting sites. Also, as soil depth increased, total porosity and coarse pore were decreased. Bulk density at uncutting sites was lower than that at clearcutting sites, and was decreased as soil depth increased. The order of the change trend in field moisture saturated hydraulic conductivity, air permeability and porosity was slope lower>middle>upper. Organic matter content at uncutting sites were higher than those at clearcutting sites, and decreased as soil depth increased. As soil depth increased, bulk density had the positive correlation, in other hand, porosity, coarse pore, field moisture saturated hydraulic conductivity, air permeability and organic matter content had the negative correlation. It was concluded that forest environmental changes by forest fire degrade soil physical and chemical properties.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.36 no.11
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• pp.1297-1303
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• 2012

In this paper, the standard procedures for measuring the moisture sorption properties of thin polymeric materials such as polyethylene terephthalate (PET) by using the thermo-gravimetric method to characterize the moisture diffusion in the polymer are presented, and the sorption properties are quantified. The moisture diffusivity and solubility are characterized to investigate the effect of temperature and humidity on the moisture sorption properties according to the Arrhenius equation. The validation of the obtained sorption properties using thermogravimetry is discussed with the measured permeability based on Fickian diffusion. The nonlinear behavior of the concentration dependent moisture diffusion is investigated experimentally, and the nonlinearity is characterized numerically for the case of having an interface with an inorganic material such as a metal. The Fickian/Non-Fickian model based on the obtained moisture sorption properties is compared and discussed.

• International Journal of Highway Engineering
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• v.11 no.2
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• pp.111-120
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• 2009

This paper presents a fundamental findings of the functional and structural performance of the porous asphalt concrete coated with MMA resin. To evaluate the structural performance, cantabro, wheel tracking, moisture sensitivity and indirect tensile fatigue tests are performed. The tests results show that the cantabro loss is reduced three times and fatigue resistance is significantly increased after the specimens are coated with MMA resin. However there are little changes in the rutting and moisture damage resistances before and after the coating. Air voids, permeability and BPT(British Pendulum Test) tests are conducted to study the functional performance. It is observed form the tests that the air voids and permeability are slightly decreased after the coating. However, the changes in the air voids and permeability are negligible. The skid resistance of the coated specimens is lower than reference specimens. However, the skid resistance is maintained beyond the level of the reference specimens when silica sands are chipped on top of the coated surface.

• Journal of the Korean Society of Clothing and Textiles
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• v.34 no.11
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• pp.1798-1811
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• 2010

This research evaluates the changes in the comfort-related properties of high-density fabric, such as moisture permeability and waterproofness, in order to assess the relative importance of laundry conditions for clothing properties after repeated laundering and suggest the best laundering conditions for high-density fabric through the identification of the most influential factor. A commercial high-density fabric was washed 25 times in a drum-type washer using nine different laundry conditions based on profiles derived from a fractional factorial design. To evaluate the changes in the comfort-related properties of the fabric, pore size, air permeability, water vapor transport, water repellency, and water resistance were measured. The comfort-related properties of the fabric deteriorated after repeated laundering by the damaged surface finish; in addition, the damaged surface also changed the pore size. As a result, the water repellency and water resistance decreased. The detergent was the most responsible factor to change the properties among the four factors of detergent, hardness, temperature, and RPM. The best laundering conditions for the fabric was a neutral detergent, soft water of 70ppm, a temperature of $15^{\circ}C$, and 30rpm.

• Computers and Concrete
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• v.13 no.3
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• pp.361-375
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• 2014

The moisture transport in underground concrete was experimentally investigated and the nonlinear model of moisture transport considering the effects of water diffusion, hydration of cementicious materials and water permeability was proposed. The consumed moisture content by self-desiccation could be firstly calculated according to evolved hydration degree of cement and mineral admixtures. Furthermore, the finite differential method was adopted to solve the moisture transport model by linearizing the nonlinear moisture diffusion coefficient. The comparison between experimental and calculated results showed a good agreement, which indicated that the proposed moisture model could be used to predict moisture content evolution in underground concrete members with drying-wetting boundaries.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.4 no.1
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• pp.23-32
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• 1997

The change in moisture content of moisture sensitive products in moisture-semipermeable packages was investigated for the purpose of predicting the shelf life of a product-package combination. A mathematical model, and a computer program based on the physiochemical properties of the product and the moisture permeability of the package was developed. The moisture content for products in moisture-semipermeable packages was determined under various environmental conditions and the results were compared with the predicted values by means of the simulation model. These experimental studies demonstrated that the prediction of the change in moisture content of packaged products over time by the simulation model is accurate, within a practical range of temperature and relative humidity values. The developed semi-empirical model is considered to have applications in industry, since it provides product shelf life information for a range of temperature and relative humidity conditions, with a limited number of experimentally obtained data points.

• Journal of the Korean Society of Clothing and Textiles
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• v.28 no.2
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• pp.303-311
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• 2004

The purposes of this study were to investigate characteristic changes on nonwoven fabric by the charcoal printing. It separate grind charcoal as two different size of particles 45-52${\mu}{\textrm}{m}$ and 53-65${\mu}{\textrm}{m}$ for hand screen printing on three kind of nonwoven fabrics. To examine the effect of charcoal printing on nonwoven fabric were to obselve surface changes by a scanning electron microscope, dyeability by using spectrophotometer, moisture regain by oven method, air permeability, anion property, deodoriration and antibacterial activity. The results were as follows： When charcoal powder concentration increased from 3 to 9％, K/S value also increased from 3.06 to 8.55. When charcoal concentration increased, moisture regain also increased. In same concentration, moisture regain occurred higher as particle of small size. Air permeability decreased when the charcoal printing concentration increased. Anion occurrence appeared 140-160ion/cc from three different kinds of nonwoven fabrics in 3％ and 9％ charcoal concentration. Therefore, occurred anion ineffectively. In concentration of 3％, rate of deodorization measured as 89％, 83％ and 87％, and 9％ concentration caused 96％, 86％ and 93％ of high deodorization. Antibacterial activity examination in nonfinished nonwoven fabric resulted range of 60％, however, 3％ and 9％ concentration finished nonwoven fabric resulted 99.9％ of excellent antibacterial activity.

• Textile Coloration and Finishing
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• v.7 no.1
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• pp.23-31
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• 1995

Changes of the properties of waterproof and moisture-permeable nylon fabric were investigated when softener, anti-static agents, anti-biosis agents were added to the polyurethane resin solution, and when they were applied after resin coating. The adding method of finishing agents into polyurethane layer resulted in an increase in water permeability but a severe decrease in peeling strength. It was found that the desired functionality such as softness, anti-staticity, anti-biosis were successfully introduced into waterproof and moisture-permeable nylon fabric by after-treatment of finishing agents.

• Food Science and Biotechnology
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• v.15 no.1
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• pp.133-137
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• 2006

Wheat gluten-chitosan composite film (WGCCF) can prevent moisture migration and enhance the antimicrobial properties of gluten in intermediate-moisture foods like sandwiches. To mimic the structure of actual sandwich-type products we developed multi-layer food models, where moisture content and water activity differ. Water activity gradients direct moisture migration and therefore determine product characteristics and product stability. A 10% wheat gluten film-forming solution was mixed with chitosan film-forming solution (0-3%, w/w) and evaporated to generate WGCCF. Addition of 3% chitosan enhanced the mechanical properties of the film composite, lowered its water vapor permeability, and improved its ability to protect against both, Streptococcus faecalis and Escherichia coli, in a 24 hr sandwich test (reduction of 1.3 and 2.7 log cycles, respectively, compared to controls). Best barrier and antimicrobial performance was found for 3% chitosan WGCCF at pH 5.1. Film of this type may find application as barrier film for intermediate-moisture foods.

• Textile Coloration and Finishing
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• v.30 no.2
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• pp.90-97
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• 2018

Hydrophilic reactive hot-melt polyurethane adhesive(HRHA) using a hydrophilic polyol having different molecular weight and NCO index was synthesized. This HRHA was synthesized using Polyethylene glycol(PEG) as a hydrophilic polyol, Polypropylene glycol(PPG) and Polycaprolactone diol(PCL) as hydrophobic polyols, and Methylene diphenyl diisocyanate(MDI) as an isocyanate. The changes in IR spectrum, viscosity and thermal properties of HRHA with different PEG molecular weights and NCO index were investigated, and the tensile strength and elongation of the HRHA casting film and the peel strength, moisture permeability and water pressure of the HRHA coated fabric were confirmed. In this experiment, as the molecular weight of PEG and NCO index increased, the adhesive strength, tensile strength, elongation and moisture permeability was increased but viscosity and Tg was decreased.