• Proceedings of the Korea Concrete Institute Conference
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• 2001.05a
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• pp.157-162
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• 2001

The purpose of this study is to investigate the enhancement of shear capacity according to steel fiber contents in RC short columns. Lateral force resistance test was performed with the parameters of steel fiber contents in concrete volume. From the test results, shear and ductility capacity was improved with steel fiber contents Increased. In addition, an optimal steel fiber content was evaluated as a 1.5 % of concrete volume.

• International Journal of Safety
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• v.11 no.2
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• pp.26-28
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• 2012

In this thesis, fracture tests were carried out in order to investigate the flexural strength behavior of FRC(fiber reinforced concrete) structures. FRC beams were used in the tests, the initial crack load and the ultimate load of the beams were observed under the static loading. According to the results, the ultimate loads increase with the fiber content, and these tendency is clear in the specimens with large fiber aspect ratio. From the results of the regression analysis, practical formulae for predicting the flexural strength of FRC were suggested.

• Proceedings of the Korea Concrete Institute Conference
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• 1998.04a
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• pp.293-298
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• 1998

The result of an experimental study on the mechanical properties and durability of polypropylene fiber reinforced concrete are presented in this paper. This study has been performed to obtain the properties of PFRC such as strength, toughness and durability. The test variables are fiber content, fiber types, W/C ratio. PFRC shows the highest strength when the polypropylene fiber contents were increased to 2.0 vol.%. Also, freeze-thaw resistance and carbonation were somewhat more improved than plain concrete.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2015.05a
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• pp.38-39
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• 2015

This study reviewed slump and air content as pre-hardening characteristics depending on B/P production of amorphous steel fiber-reinforced concrete and evaluated compressive strength, flexural strength and tensile strength as post-hardening characteristics depending on B/P production of amorphous steel fiber-reinforced concrete.

• Journal of Nutrition and Health
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• v.22 no.6
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• pp.485-496
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• 1989

This study was performed to investigate nutritional effect of various dietary fibers on lead absorption and metabolism of protein and lipid in growing rats. Forty eight male rats of Sprague-Dawley strain weighing 75.7$\pm$0.7g were blocked into six groups according to body weight and fed six kinds of diet different with fiber source(non-fiber, cellulose, pectin) and lead level(0%, 1% ) for 4 weeks. Results are summerized as follows: 1) Food intake, weight gain, FER and PER were remarkably decreased in lead(Pb) added groups, and FER and PER in Pb-added pectin group were significantly lower than those in Pb-added non-fiber group. 2) Weight of liver, kidney and epididymal fat pad, bone weight and length, hematocrit, and hemoglobin content were decreased in Pb-added groups. 3) Total protein content in serum was tended to be decreased in Pb-added groups, but total lipid and cholesterol contents in serum were not different with dietary Pb level and fiber source. 4) Nitrogen, lipid and cholesterol content in liver were tended to be deceased in Pb-added groups, and especially those of the Pb-added pectin group were the lowest among groups. 5) Daily urinary and fecal excretions of nitrogen, lipid and cholesterol were decreased in Pb-added groups. Especially fecal excretions of nitrogen, lipid and cholesterol in Pb-free groups were significantly increased by dietary cellulose and pectin. 6) Pb content in blood was significantly increased in Pb-added pectin group. There was no significant decrease in Pb contents of liver, kidney and tibia, and increase in excretion of Pb by feeding dietary fibers. In conculsion, dietary fibers had no effect on the absorption of Pb, and dietary pectin seemed to increase Pb poisoning by decreasing bioavailibility of protein, lipid and other nutrients in the diet.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2006.05a
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• pp.27-30
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• 2006

This study investigated influence of organic fiber type and contents on engineering properties of concrete. Test showed that increase of fiber contents decreased fluidity of fresh concrete and it was even worse in concrete adding cellulose fiber. It is decided that concrete containing more than proper level of fiber should be considered. In addition, concrete adding more fiber, nylon and cellulose, resulted in increase of air content but it was satisfied in aimed value. Bleeding capacity of concrete containing more fiber significantly declined and setting time of that was also slightly retarded. For the properties of strength, both compressive and tensile strength of fiber containing concrete were indicated at similar value to control concrete. However, it is clear that if those concrete containing fiber revised the value of increased air contents at fresh state, the strength value of that would be slightly increased.

• Carbon letters
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• v.12 no.2
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• pp.70-80
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• 2011

Two pitches with different average molecular structures were electrospun and compared in terms of the properties of their fibers after oxidative stabilization, carbonization, and activation. The precursor with a higher molecular weight and greater content of aliphatic groups (Pitch A) resulted in better solubility and spinnability compared to that with a lower molecular weight and lower aliphatic group content (Pitch B). The electrical conductivity of the carbon fiber web from Pitch A of 67 S/cm was higher than that from Pitch B of 52 S/cm. The carbon fiber web based on Pitch A was activated more readily with lower activation energy, resulting in a higher specific surface area compared to the carbon fiber based on Pitch B (Pitch A, 2053 $m^2/g$; Pitch B, 1374 $m^2/g$).

• Proceedings of the Korea Concrete Institute Conference
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• 1990.04a
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• pp.5-10
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• 1990

There are two main methods in reinforcing cements with glass fibers : spray-suction and premixing method. But GRC have been mostly studied by spray technique. In order to develop GRC made by premixing method, in this paper, the influence of glass fiber length, volume content and curing conditions upon the compressive, direct tensile and bending strengths of composites fabricated by a premixing method, were investigated. According to the test results, although it was difficult to obtain perfectly uniform distribution of fibers in GRC Pannel, it was found that tensile strength of cements with glass fiber was improved 2~5 times and flexural strength 4 times compared to conventional cement mortar upto fiber length 35 mm, volume content 4%.

• Composites Research
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• v.26 no.5
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• pp.273-278
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• 2013

PLA/PP polymer blends in various ratios (PLA:PP = 9:1, 4:1, 3:1, and 1:1), and their composites (PLA:PP = 1:1) with sisal fiber (10, 15 and 20 wt%) were fabricated using MAPP as compatibilizer. The aim of the work was to reduce the cost of biodegradable composites as well as to improve the impact strength of PLA using PP, a relatively cheaper thermoplastic. The developed composites were characterized for their morphological and mechanical properties. The tensile strength and modulus of the blends were decreased with increasing PP content whereas the strain at break and impact strength are increased. The tensile strength, modulus and water absorption were increased for hybrid composites with increasing fiber content.

• The International Journal of Costume Culture
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• v.5 no.2
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• pp.53-65
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• 2002

Morphology of polyester fiber was physically modified by solvent treatment. PET fiber was treated with N,N-dimethylformamide (DMF) at 100, 120, $140^{circ}C$ for 10 minutes without tension. The structural changes in the morphology of DMF-induced modified PET fiber were FTIR and SEM analysis. Also dyeing behavior of DMF-treated polyester fibers with various disperse dyes was studied to detect changes of amorphous area in fine structure. DMF treatment resulted in increases in total void content, degree of crystallinity, trans isomer content, chain folding, segmental mobility and molecular packing, but it resulted in decreases in amorphous orientation, intermolecular forces and individual void size through longitudinal shrinkage, lateral welling and removal of oligomers. Void-size distribution could be estimated from the dye uptake with various sizes of disperse dyes. In contrast to the large increases in dye uptake with small dye molecules, there is no and little dye uptake with the bulkiest dye, which means that void size is bigger or smaller than the volume of each dye. Diffusion rates of dye molecules showed increases. This dyeing study revealed that the disperse dyeing is very effective method for characterizing the internal morphology of polyester fiber.