• 한국건축시공학회지
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• 제11권4호
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• pp.353-362
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• 2011

High Strength Concrete (HSC) has weakness that in a fire, it is spalled and brittles. The phenomenon of spalling is made by water vapor's being confined in watertight concrete. This study is aimed to evaluate explosive spalling properties of high strength concrete with ${\square}100{\times}100{\times}200$ mm specimen and ${\square}400{\times}400{\times}1500$ mm column. To prevent spalling of concrete, fireproof coating and PP fiber are used. As a result, ${\square}400{\times}400{\times}1500$ mm column was prevented spalling likes ${\times}100{\times}100{\times}200$ mm specimen. When concrete protected failure to explosive spalling, quantity heat ratio (which fireproof coating specimen to pp fiber mixed specimen) between ${\square}100{\times}100{\times}200$ mm and ${\square}400{\times}400{\times}1500$ mm was maximum value at 20 minute, but difference of quantity heat ratio decreased and quantity heat ratio of each specimen is almost same at 30 minute.

• 한국농공학회논문집
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• 제62권4호
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• pp.23-31
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• 2020

Recently, meteorological disasters have been increasing by climate change, excessive rainfall, and landslide. The purpose is to develop new fabric concrete that can prevent and recover from damages because some of areas are vulnerable to meteorological disaster. Specifically, this technology can minimize time and space constraint when repairing the concrete structure and installing a formwork. The structure of fabric concrete is a mixture of fabric concrete and a high-speed hardened cement, Silica sand, wollastonite mineral fiber, fabric material and waterproof PVC fabric. In this study, the ratio of mechanical properties and durability of the fabric concrete mixture was evaluated by deriving the binder: silica sand mix ratio of the fabric concrete mixture and substituting part of the cement amount with wollastonite mineral fiber. Best binder in performance evaluation: Silica sand mix ratio is 6: 4 and the target mechanical performance and durability are the best when over 15% wollastonite binder is replaced by silicate mineral fiber.

• 동아시아식생활학회지
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• 제9권1호
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• pp.27-34
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• 1999

This study was carried out to investigate the effects of the kinds and the amounts of dietary fiber on serum lipid composition in rats. Seventy-two male Sprague-Dawley rats weighting 160$\pm$10g were fed diets containing 1.0%, 3.6%, 6.0% and 10.0% $\alpha$-cellulose, pectin and alginic acid fer 4 weeks. Daily food intake of experimental groups was significantly higher in the u-cellulose 10.0% group than in the other groups. Increasing the dietary fiber level decreased the food efficiency ratio of the $\alpha$-cellulose, pectin and alginic acid groups. Serum triglyceride concentration was significantly lower in the rats fed the alginic acid diet. Serum total cholesterol concentration showed no significant difference in the kind and the amount of three dietary fibers. Serum HDL-cholesterol concentration was higher in $\alpha$-cellulose and pectin diet. HDL-cholesterol/total cholesterol ratio was higher in u-cellulose and pectin diet than alginic acid diet. In conclusion, alginic acid is good for the serum triglyceride decrease, pectin is good for HDL-cholesterol increase, $\alpha$-cellulose and alginic acid are good for HDL-cholesterol/total cholesterol ratio increase. But the different effects according to the dietary fiber's contents did not show a significant trend.

• 펄프종이기술
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• 제35권4호
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• pp.68-74
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• 2003

Kenaf(Hibiscus cannabinus L.) cultivar, Tainung 2, had been grown for 152 days at the experimental farm of Jinju National University, Gajoa-dong, Jinju-si, Kyongnam, Korea. The planting, growth rate, fertilization and structural characteristics as well as the cultivation and growth characteristics of kenaf, and the product usage were investigated. The narrowest diameter at kenaf bottom was 10 mm, the widest 42 mm and the average about 28 mm, and the shortest height 150 cm, the tallest 480 cm and the average about 350 cm. The weight of a core fraction was 68.1％ and a bast fraction 31.9％. The weight ratio of core material to bast fiber was 2.31. The weight ratio of dry stem was 73.5％ and that of leaves 26.5％. The weight of dry plant produced in 1 $m^2$ was 1,467 g, and about 1,052 g of stem could be used for the commercial purpose, The application of fertilizers resulted in the increase of the growth rate of the diameter at plant bottom and the height. Bast fiber, phloem ray and cortex parenchyma cell were observed in bast, and vessel, wood fiber and ray in core.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2006년도 춘계 학술발표회 논문집(II)
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• pp.405-408
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• 2006

The purpose of this study was to determine the optimum length distribution of hybrid PVA(Poly vinyl alcohol) fiber. To produce blended PVA fiber length, first the length distribution of PVA fiber in the cement composites were identified in an experimental study based on simplex lattice design. Among the different length distributions investigated, fiber length was found to have statistically significant effect on plastic shrinkage cracking of cement composites. Subsequently, Complex analysis techniques were used to devise an experimental program that helped determine the optimum combinations of the selected fiber length distribution based on plastic shrinkage crack. The optimum blended PVA length ratio was 0.0146% 4mm fiber, 0.0060% 6-mm fiber, 0.0285% 8-mm fiber, and 0.0209% 12-mm fiber.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2015년도 춘계 학술논문 발표대회
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• pp.65-66
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• 2015

In this study, it evaluate mecahnical performance and impact resistance performance of fiber reinforced concrete, fiber reinforced mortar and preplace grout mortar. steel fiber, nylon fiber and polypropylene fiber are reinforced 1vol.% 2vol.% 10vol.% by each fiber type. It evaluate impact resistance performance to use projectile 10mm of 400m/s velocity. As a result, mechnical performance and impact resistance performance of fiber reinforced preplace grout mortar are improved a lot by 10% fiber reinforced ratio.

• 한국식품영양학회지
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• 제12권1호
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• pp.20-25
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• 1999

The study was conducted to investigate the effect of cholesterol and fiber on liver lipid metabolism in rats. Male Sprague Dawley rats were administrated 1% cholesterol and 0.25% sodium cholate to induce hypercholesterolemia and were fed diet containing three levels(0%, 5% and 10%) of cellulose and pec-tin respectively. The rats were sacrified after 5 weeks of feeding period. Net weight gain and feed ef-ficiency ratio were increased in 10% fiber groups as compared to those of 5% fiber groups. Feed intake did not show significancy by fiber kinds and levels. Liver and kidney weights tended to be decreased in proportion to level of fiber. Heart weight was lowered in 10% fiber groups as compared to that of 5% fi-ber groups. Liver triglyceride concentration was significantly increased in pectin groups. Total-free-cholesterol and cholesteryl ester concentrations in liver were significantly decreased by fiber and were decreased in proportion to level of fiver. Phospholipid concentration was significantly decreased by fiber and were decreased in proportion to level of fiber. Phospholipid concentration was significantly decreased in 5% cellulose group. the results indicate that 10% pectin may have beneficial roles in hypercholester-olemia.

• 한국섬유공학회:학술대회논문집
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• 한국섬유공학회 2000년도 봄 한국섬유공학회 학술발표회 논문집(Proceedings of the Korean Textile Conference)
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• pp.105-108
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• 2000

• 대한치과기공학회지
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• 제31권4호
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• pp.37-43
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• 2009

This study evaluated the effect of concentration of glass fiber reinforcement on the flexural properties of auto and heat polymerized denture base resin. The test specimens($64{\times}10{\times}3.3mm$) were made of auto and heat polymerized resin(Vertex, Dentimax, Netherlands). Glass fiber(ER 270FW, Hankuk Fiber Glass, Korea) were used to reinforce the denture base resin. The 2.6%, 5.3% and 7.9% volume pre-impregnated fiber were located at the bottom of specimen. The test specimens(n=7) of each group were stored in distilled water at $37^{\circ}C$ for 50 hours before test. The flexural strength and modulus were measured by an universal testing machine(Z020, Zwick, Germany) at a crosshead speed of 5 mm/min in a three-point bending mode. The data was analyzed by one-way ANOVA and the Duncan's multiple range test(${\alpha}$=0.05). The difference of auto polymerized resin groups and heat polymerized resin groups were statistically analyzed by t-test(${\alpha}$=0.05). Glass fiber showed significant reinforcing effects on auto and heat polymerized resin. For flexural strength and modulus, auto polymerized resin was the highest in 7.9% volume, while heat polymerized resin was the highest in 5.3% volume. In this study, glass fiber at 7.9% volume ratio showed most effective reinforcing effect on auto polymerized resin and glass fiber at 5.3% volume ratio showed most effective reinforcing effect on heat polymerized resin in terms of flexural strength and flexural modulus.

• 콘크리트학회지
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• 제4권1호
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• pp.81-87
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• 1992

본 논문에서는 강섬유 혼입량과 강섬유 형상비에 대한 강섬유보강콘크리트의 휨 피로거동을 분석하기 위하여 일련의 강섬유보강콘크리트 시험체에 대하여 피로실험을 수행하였다. 피로실험은 3점 휨 실험법으로 실시하였으며, 실험시 각 시험체의 하중반복회수에 대한 중앙처짐과 피로파괴시의 반복회수를 조사하였다. 이들 실험 결과를 토대로 반복회수에 대한 강섬유보강콘크리트의 중앙처짐, 비탄성변형에너지 및 탄성변형형에너지등을 비교 분석하였으며, 강섬유보강콘크리트의 S-N선도를 작도하였다. 연구결과, 강섬유 혼입량이 클수록 영구변형에 손실되는 에너지가 크게 감소하고, 균열 확대에 소모되는 에너지가 증가하였으며, 동일한 강섬유 혼입량을 갖는 강섬유콘크리트의 경우 강섬유 형상비가 클수록 탄성변형에너지는 작았다. 아울러 본 피로실험 결과를 회귀분석하여 구한 S-N선도에 의하면 강섬유 혼입량이 1.0%인 강섬유보강 콘크리트의 반복회수 200만회에 대한 피로초기균열 발생시의 정적강도의 약 70%로 나타났다.