• Proceedings of the Korea Concrete Institute Conference
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• 1998.10b
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• pp.809-814
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• 1998

Recently many cases that using strengthening method with a steel plate or carbon-fiber sheet in a construction field are increasing. In this reason, it is demanded that developing a plan of preventing delamination of strengthening material. So in this research, for the case of strengthening method of steel plate, it is made use of notch and anchor bolt and for the case of carbon fiber sheet, it is made use of notch, anchor bolt, line anchor and shear strengthening. After all the cases were applied, we made 15 specimen beams. The beams was measured and analyzed about the behavior property of strengthened beams, the ability strengthening method, the relation between load and the shape of failure, the crack load, the yield load, the shape of crack pattern, the increasing rate from yield load and maximum load and the strain of rebar. All the strengthening methods results in almost same value until the yield load, and it wasn't quite different from the theoretical value. But for the case of increasing rate from the yield load and maximum load, comparing with the existing method, the new strengthening methods are proved to be profitable about the safety.

• Proceedings of the Korean Fiber Society Conference
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• 2003.04a
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• pp.13-16
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• 2003

Vinyl acetate monomer can be polymerized through bulk, solution, emulsion, and suspension polymerization processes. However, in the preparation of PVA from bulk or solution polymerization, there are several technical limitations for obtaining high yield and high molecular weight simultaneously. Thus, the improvement of polymerization method is necessary to prepare the PVA with high yield and high molecular weight because that the difficulty in control of high viscosity and in removal of the heat of polymerization, which might lead to side reactions like branching. (omitted)

• Proceedings of the Korean Fiber Society Conference
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• 1999.10a
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• pp.25-28
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• 1999

• Proceedings of the Korean Fiber Society Conference
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• 1999.10a
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• pp.429-432
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• 1999

• Journal of the Korean Society of Clothing and Textiles
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• v.15 no.3 s.39
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• pp.271-280
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• 1991

Emulsion graft copolymerization of MMA onto cotton fiber using Ce(IV) salt as an initiator was carried out. Graft yield and graft efficiency were observed according to the kinds and concentrations of emulsifier and polymerization conditions. The physical properties of MMA grafted cotton fabric were investigated. The results of this study were as follows: 1. The heighest graft yield of emulsion graft polymerization occurred at the concentration below cmc of emulsifier, which was different from emulsion polymerization. Nonionic sur- factant as an emulsifier was more effective than anionic one. 2. The highest graft yield was obtained at the initiator concentration $1{\times}10^{-2}mol/l$. The viscometric molecular weight of PMMA was in the order of 106. 3. As reaction time increased, the graft yield increased but the graft efficiency decreased. 4. Elevation of reaction temperature resulted in increase of graft yield. The apparent activation energy of MMA graft polymerization was 4.72 Kcal/mol. 5. Physical properties of MMA grafted cotton fabric varied with increase of grafting. Thickness and stiffness showed a noticeable increase, whereas tensile strength and elongation was slightly increased. Crease recovery increased as the graft yield increase up to $50\%$ and decreased thereafter.

• Journal of The Korean Society of Grassland and Forage Science
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• v.40 no.1
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• pp.37-43
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• 2020

This study was conducted to evaluate the effects of different nitrogen levels on the yield and nutrient quality of a newly developed domestic hybrid of Teosinte, Geukdong 6〔Zea mays L. subsp. mexicana (Schrad.) H. H. Iltis〕. The field experiment was conducted in a randomized block design with three replicates and consisted of four nitrogen (N) application rates, T1 (200 kg/ha), T2 (300 kg/ha), T3 (400 kg/ha), and T4 (500 kg/ha). No differences were found in plant length, leaf length, leaf width, leaf number, dead leaves, stem hardness, tiller number, and fresh yield (p>0.05). The T3 showed significantly greater dry matter yield at harvest (heading stage) compared to the other treatments (p<0.05). The crude protein content of T4 (10.49%) was higher than those of T1 and T2 (p<0.05). However, there was no significant difference between T4 (10.49%) and T3 (9.63%). The effects on crude fat, crude ash, neutral detergent fiber (NDF), acid detergent fiber (ADF), and crude fiber were not significant (p>0.05). The sugar content was higher in the T2 treatment than the other treatments (p<0.05). For Ca, T3 showed significantly greater content (p<0.05). However, no significant effects were found in the contents of Cu, Fe, K, Mg, Mn, Mo, and Zn (p>0.05). Na content was higher in order of T2 > T4 > T3 > T1 (p<0.05). Total mineral contents were not significantly different among the treatments (p>0.05). Given these results, we recommend the amount of nitrogen fertilization necessary for "Geukdong 6" to be around 400 kg per ha (T3), when considering, high fresh yield, dry matter yield, number of leaves and content of crude protein.

• Journal of Animal Science and Technology
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• v.61 no.5
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• pp.278-284
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• 2019

This study was carried out to investigate the effects of seeding dates on the yield and feed value of whole-crop barley cultivated in paddy soil. The field experiment was conceived as a randomized block design performed in triplicate with seeding dates of Oct. 19 (T1 as treatment 1), Oct. 26 (T2 as treatment 2), Nov. 2 (T3 as treatment 3), Nov. 9 (T4 as treatment 4), and Nov. 16 (T5 as treatment 5) as treatments. The barley grown in all treatments was harvested on May 21 of the following year. Plant length, fresh yield, dry matter yield, and total digestible nutrient (TDN) yield were higher (p < 0.05) in barley with early seeding dates, whereas crude protein and ether extract were higher (p < 0.05) with late seeding dates. Crude fiber and neutral detergent fiber were highest in the T3 treatment and lowest in the T1 treatment. There was no significant difference between acid detergent fiber and TDN among the different seeding dates. Total mineral contents were higher in the order T1 > T2 > T3 > T4 > T5 (p < 0.05), whereas the total amino acid content increased significantly (p < 0.05) with a delay in seeding date. Free sugar contents (fructose, glucose, and sucrose) were higher with early seeding dates (p < 0.05). Collectively, the results obtained in this study indicate that it is favorable to seed soon after harvesting rice to increase dry matter and TDN yields and mineral and free sugar contents of whole-crop barley in the midlands of Korea.

• Journal of Animal Science and Technology
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• v.63 no.1
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• pp.137-148
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• 2021

The effect of the addition of dietary fiber extracted from wheat, bamboo, and oat on the quality of fried pork loin batter was investigated. Quality evaluation included proximate composition, pH, color, viscosity, coating and frying yield, electronic nose, and sensory evaluation. Regarding proximate composition of fried batter and fried pork loin, the water content of the dietary fiber treatments was significantly higher than that of the control (p < 0.05), whereas fat content was significantly lower than that of the control (p < 0.05). The lightness of non-fried batter with dietary fiber treatments was significantly higher than that of the control (p < 0.05), whereas the yellowness was significantly lower than that of the control (p < 0.05). The lightness, redness, and yellowness of fried pork loin with dietary fiber treatment were significantly lower than those of the control (p < 0.05). The viscosity and coating and frying yield of dietary fiber treatments were significantly higher than those of the control (p < 0.05). The volatile compounds of dietary fiber treatments were decreased "tallowy" flavor and increased "buttery" and "milky" flavor. The principal components of bamboo and oat fiber treatments were clearly distinguishable from those of the control; however, similar principal components as those of the control were obtained with wheat fiber treatment. Regarding sensory evaluation, the color, texture, and overall acceptability of wheat and oat fiber treatments were significantly higher than those of the control (p < 0.05), and the flavor of the wheat fiber treatment was significantly higher than that of the control (p < 0.05). These results show that wheat and oat fibers are suitable for fried pork loin batter and improve its quality.

• Journal of the Korean Society of Clothing and Textiles
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• v.17 no.3
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• pp.347-358
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• 1993

Graft copolymerization of MMN4-VP onto cotton fiber using Ce(IV) salt as an initiator and triton X-100 as an emulsifier was performed under various polymerization conditions. In cograft polymerization, the polymeization behavior according to variation of 4-VP feed composition and the characteristics of MMA/4-VP graft polymer such as affinity for acid dye owing to cationization of cotton, antibacterial activity and thermal behavior were investigated. The results of this study were as follows : 1. While in copolymerization of MMA and 4-VP, 4-VP content in copolymer was more than that of monomer feed composition. 2. Increasing 4-VP content, graft yield was decreased, but graft efficiency was increased. In case of MMA/4-VP graft polymerization, the highest graft yield was obtained at higher CAN concentration than in MMA graft polymerization, the reason is that the behavior of 4-VP was disturbed by Ce(IV) sail 3. Elevation of temperature resulted in increase of graft yield and the apparent activation energy of MMA/4-VP graft polymerization was higher than that of MMA graft polymerization. 4. MMA/4-VP grafted cotton fiber showed affinity for acid dye, antibacterial activity and higher moisture regain than MMA grafted cotton fiber. MMA/4-VP grafted cotton fabric showed improvement of wrinkle recovery up to 40~50% graft yield and decreased thereafter. MMA/4-VP and MMA grafted cotton fabric did not showed significant difference in wrinkle recovery and stiffness.

• Food Science of Animal Resources
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• v.32 no.6
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• pp.732-739
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• 2012

The aim of this study was to investigate the effect of chicken feet gelatin and wheat fiber levels on the quality characteristics properties of semi-dried chicken jerky. The obtained chicken feet gelatin swollen with hydrochloric solution (0.1 N HCl, pH $1.31{\pm}0.02$) was dehydrated via freeze-drying. Six formulations of chicken jerky that were prepared, based on the ratio of chicken meat, chicken feet gelatin and wheat fiber, were 100:0:0, 98:0:2, 99:1:0, 97:1:2, 98:2:0 and 96:2:2, respectively. The moisture content of semi-dried chicken jerky containing 2% wheat fiber was higher than that of jerky without the added fiber (p<0.05); moreover, an increase in the content of chicken feet gelatin also increased the moisture content. The drying yield of the samples increased with an increase in chicken feet gelatin. In addition, the drying yield of samples containing 2% wheat fiber was higher (p<0.05) than those without the added wheat fiber. However, the shear force of the samples significantly decreased with the increase in chicken feet gelatin content. Further, the shear force of the samples containing 2% wheat fiber was higher (p<0.05) than those without the added wheat fiber. No significant differences, except for color, were observed in the sensory analysis among the treatments.