• Journal of the Korea Furniture Society
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• v.26 no.4
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• pp.428-434
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• 2015

In this study, we received each wood plastic composites (WPC) from three manufacturers. These WPCs were evaluated regarding their physical and mechanical properties of both before and after accelerated weathering by ultraviolet (UV) irradiation. The total time of exposure of the WPCs to UV irradiation was 1800 h. The water absorption, volumetric swelling and shrinkage of WPCs did not affected by UV irradiation. Among the mechanical properties, there was no significant differences in bending strength and screw withdrawal resistance of UV treated WPCs compared with those of reference WPCs. However, surface hardness of WPCs showed decrease under UV irradiation. Stereoscopic microscopy observation revealed deterioration of the surface layer polymer in all weathered WPCs by UV. Exposure of the WPCs to UV irradiation caused decomposition and disappearance of the polymer layer. From this result, we can estimate that damage of polymer by UV led to a decrease in the surface hardness of the WPCs. The wood flours retained original shape after accelerated weathering by UV irradiation.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.50 no.2
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• pp.120-124
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• 2005

Expanded rice husk (ERR) is different from commercial rice seedling media in chemical and physical properties such as pH, permeability, and water content. This study was conducted to test a possibility of improving rice seedling growth by improving the texture of ERR as a rice seedling medium. The seedling media used were a commercial seedling medium (CSM), rice husk, and ERR 1, 2, 3, and 4 with different expansion degrees. The pH of the ERHs ranged from 6.3 to 6.8. As the expansion rate increased, ERR particle sizes decreased, and water permeability and absorption rates improved. No significant differences in shoot dry weight and rate of maturity were found among the seedlings cultivated in the different ERH media. However, the mat formation of seedling roots became loose as the expansion rates were decreased. Further studies are necessary to determine the cause of poor root growth in ERH media.

• Journal of the Korean Society of Food Culture
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• v.33 no.1
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• pp.62-69
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• 2018

The purpose of this study was to investigate the antioxidative and physical properties of finger food type rice snacks and pumpkin rice snacks for infants aged 6 to 12 months old. The addition of rice germ did not affect density or porosity, and there was no significant difference when compared with commercial products. The addition of rice germ to the rice snack group did not reduce the longitudinal expansion quality of the rice snack. The WAI of RW and SW values were 9.83 and 8.93, respectively, which were significantly higher than those of other samples (p<0.05). The results of this study show that the addition of rice germ to rice snack resulted in reduced density and porosity of rice snacks and maintenance of a high water absorption index, which are more desirable characteristics for products. The products with rice germ showed significantly higher antioxidative activities among all samples (p<0.05).

• The Journal of Korean Physical Therapy
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• v.21 no.2
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• pp.87-95
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• 2009

Purpose: This study reports the basic reference data of the specific gait parameters for Korean normal adults. Methods: The basic gait parameters were extracted from 73 Adults (35 men and 38 women), 18 to 33 years of age, using a Vicon MX motion analysis system. The segment kinetics, such as joint moment and power, was analyzed at the hip, knee and ankle. Results: The motion patterns are typically associated with a specific phase of the gait cycle. The temporal-spatial gait parameters of Korean normal adults, such as cadence, walking speed, stride length, single support and double support, were similar to the other western reference data. The kinetic parameters of Korean normal adults, such as joint moments of force, joint mechanical power generation or absorption and ground reaction forces, were also similar to other western reference datasets. Conclusion: This study demonstrates that objective gait analysis can be used to document the gait patterns of normal healthy adults. The techniques of 3-dimensional temporal-spatial gait parameters and kinematic parameters analysis can provide a detailed biomechanical description of a normal and pathological gait.

• 보존과학연구
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• s.27
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• pp.145-163
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• 2006

This study is to be investigated through firing experiment in studio in order to reveal a physical properties of celadon according to change firing temperature. The results can be briefly summarized as below; Firstly, in measurement of color chromaticity, samples of first firing in body were effective in differentiating of changed color in samples from each other but there of second firing were not. The color of the glaze was more effective change than that of the body. Secondly, bulk density of body was increased with temperature and it was attained highest point in $1200^{\circ}C$ Additionally, water absorption ratio was most rapidly changed between $1000^{\circ}C$ and $1200^{\circ}C$Thirdly, in the microstructural analysis, body of samples in first firing have not specific characteristics in the changed patterns of microstructure. body and glaze of samples in second firing have many that. Consequently, we knew that this experiment can be provided researcher with physical properties and firing mechanisms of celadon.

• Journal of the East Asian Society of Dietary Life
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• v.24 no.3
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• pp.368-374
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• 2014

We investigated the physical and cooking properties of commercial noodles supplemented with functional ingredients. RVA (rapid visco analyzer), color, water activity, texture and cooking properties were tested. Noodles containing kudzu showed the highest initial gelatinization temperatures, whereas noodle containing kelp displayed the highest peak viscosity and set back. Holding strength and final viscosity were highest in noodles containing mugwort. The L value ($94.89{\pm}0.02$) of wheat flour noodle was the highest. Among functional noodles, L value ($88.65{\pm}0.01$) and a value ($7.42{\pm}0.02$) of cactus noodle were the highest, whereas b value of pumpkin noodle was $40.81{\pm}0.03$, which was higher value than in other noodles. Water activity of cactus noodle was highest (0.455), but the difference was not significant. Cooking properties (including weight, volume, and water absorption) and turbidity of pumpkin noodles showed the highest growth rate. In terms of texture, hardness was highest ($12836.8{\pm}7.1g/cm^2$) in green tea noodles, and cohesiveness and gumminess were highest in kelp and mugwort noodles. Considerig the quality characteristics of noodles supplemented with mulberry leaves, cactus, mugwort, green tea, pumpkin, kelp or kudzu, pumpkin noodles were most stable in terms of gelatinization and cooking properties.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.40 no.1
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• pp.47-54
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• 2008

As the demands of environment protection increases, the pulp mold container is developed to substitute for EPS (expanded polystyrene) as a shock absorbing packaging material. The water-absorbing ratio and mechanical properties such as tensile strength and compressive strength of pulp mold are important factors to evaluate its shock absorbing characteristics. Influences of mixing ratios of ONP (old newspaper) and OCC (old corrugated container) on physical properties of pulp mold were investigated at various conditions of temperature and relative humidity. The optimum mixing ratio of ONP and OCC was also searched based on physical properties. The results showed that when relative humidity was increased from 60% to 90%, the water absorption ratio of pulp mold increased significantly, tensile strength decreased 20$\sim$30%, and compressive strength decreased 10$\sim$20%. In addition, the optimum mixing ratio of ONP and OCC was found to be 50%:50%.

• Archives of Pharmacal Research
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• v.8 no.3
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• pp.99-107
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• 1985

The interaction of reduced riboflavin 2', 3', 4', 5'-tetrabutyrate with salicylic acid, aspirin, and salicylamide has been spectroscopically investigated to determine the binding mechanism. Hydrogen-1 and carbon-13 unclear magnetic resonance, infrared, and absoption spectra were measured in chloform-d and chloroform. The association of the reduced riboflavin with salicylic acid derivatives is different from that osidizd one. Salicylic acid and the reduced riboflavin form a cyclic hydrogen bounded complex through the imino (3-N, 5-N) protons and the carbonyl (2-C, 4-C) oxygens of the isolloxazine ring of the latter, and the carboxylic hydroxyl proton and carbonyl oxygen of the former. Aspirin and the reduced riboflavin form a complex by the same mode as salicylic acid. Salicylamide forms a cyclic hydrogen bonded complex with the reduced riboflavin through the imino (3-N, 5-N) protons and the carbonyl (2-C, 4-C) oxygens of the isoalloxazine ring, and the amino proton and the carbonyl oxygen of salic aylmide. It appears that both the oxidized and reduced form of riboflavin are associated with salicylic acid derivatives.

• Journal of the Korean Wood Science and Technology
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• v.31 no.4
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• pp.1-7
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• 2003

Anatomical and physical characteristics of damaged wood by forest fire and sound wood of Pinus densiflora were examined. Granular substances were found in resin canals, epithelial cells and ray parenchyma cells of damaged wood, but the other distinctive marks of wood structure in damaged wood were not observed. Damaged wood showed slightly higher relative crystallinity in outermost growth ring than sound wood. Green moisture content and water absorptions both in tangential and radial sections of damaged wood were lower than those of sound wood. There were no significant differences in shrinkage, swelling and basic density between damaged and sound woods.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2021.05a
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• pp.146-147
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• 2021

An increase in carbon emissions leads to the problem of global warming and is an issue to be solved in other countries. The problem of carbon dioxide has many effects not only on global warming but also on people. According to the World Health Organization (WHO), 4.3 million people have died because harmful substances generated indoors cannot be discharged to the outside and accumulate in the human body through the respiratory tract. In response to this situation, in order to reduce the generation of pollutants in the building itself, soak into lightweight bubble concrete to adsorb and purify indoor pollutants, mix charcoal, investigate the appropriate amount and physical characteristics, and check carbon dioxide This is an experiment for grasping the adsorption capacity, and the results are as follows. As the replacement rate of rice husk charcoal increased, the compressive strength tended to decrease, and the carbon dioxide reduction rate tended to increase. It is judged that the charcoal of rice husks shows a low density and the physical adsorption is smooth due to the porous structure. Since it is excellent in the basic physical properties and carbon dioxide adsorption surface of this experiment, it is judged that it has sufficient potential for use as an indoor finishing material.