• Korean Chemical Engineering Research
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• v.50 no.1
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• pp.30-34
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• 2012

For the purpose of development of polymeric material for marine applications, the effects of silica and chopped glass fiber on tensile strength of polyester resin were studied. A series of experiments were performed with different contents of silica and chopped glass fiber. Tensile strength of polyester resin was increased with the contents of unmodified glass fiber, and decreased with that of silica. The surfaces of silica and chopped glass fiber were modified with coupling agent at different concentrations, and the modification showed positive effect on the increase of tensile strength of polyester resin. Synergistic effect on the tensile strength of polyester resin was observed by modified silica and chopped glass fiber.

• Journal of the Korea Institute of Building Construction
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• v.17 no.1
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• pp.1-8
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• 2017

Recently, because of the terrorisms or warfare, the damages of human life or facilities have been increased. Hence, the Korean government launched the research group for high performance fiber reinforced cementitious composite (HPFRCC) with increased demanding on protecting and anti-explosive structures. Therefore, in this research, to apply the HPFRCC on military facilities with optimum performance on workability and performance, the fundamental properties and reduction of autogenous shrinkage of HPFRCC with various combinations of steel and organic fiber and emulsified refined cooking oil (ERCO) were evaluated. As a result, based on the comprehensive analysis, for favorable workability, strength, and autogenous shrinkage, 1.5 % of combined fiber of short steel fiber and long organic fiber and 0.5 % of ERCO was suggested as an optimum conditions.

• Journal of Preventive Medicine and Public Health
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• v.33 no.4
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• pp.477-483
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• 2000

Objectives : To obtain reference values for the pulmonary asbestos and non-asbestos fiber contents of residents in Korea and to compare them with similar results from Japan. Methods : The autopsied lung specimens from 22 deceased people (20 males and 2 females) in Pohang, without any known occupational history of asbestos exposure, were analyzed for incidence of asbestos and non-asbestos fibers by transmission electron microscopy with energy dispersive X-ray analysis after using low temperature ashing procedures. Results : Chrysotite fiber (46.2%) was the major fiber type found in the lungs of the subjects. The asbestos fiber concentrations found in males and females were $0.09\times10^6$ fiberss(g of dry lungs) and $0.30\times10^6$ fibers/(g of dry lungs), respectively, showing a geometric mean concentration $0.09\times10^6$ fibers/(g of dry lung tissue), due to the predominance of males in the sample. The non-asbestos fiber contents in males and females were $4.61\times10^6$ fibers/(g of dry lungs) and $17.79\times10^6$ fibers/(g of dry lungs), respectively, with a geometric mean concentration $5.21\times10^6$ fibers/(g of dry lung tissue). Conclusions : Residents in Pohang had significantly lower levels of both asbestos and non-asbestos fibers than urban residents in Korea. Furthermore, Koreans had significantly lower levels of both asbestos and non-asbestos fibers than Japanese.

• Journal of the Korean Wood Science and Technology
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• v.32 no.1
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• pp.1-8
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• 2004

This study was carried out to investigate the sheet properties of Indian mallow Hanji, made by different pulping methods, such as alkali and sulfomethylated pulpings, and different stock compositions, various mixing ratios of bast fiber and woody core fibers. Indian mallow hanjis made from the sulfomethylated pulps had higher brightness and sheet strength than the alkali pulps. It was found that the brightness of sulfomethylated pulp was enough high without an extra-bleaching. In the mechanical properties of Indian mallow hanjis mixed with bast fiber and woody core stalk pulps, the sheet strength were decreased as wood core pulps contents were increased. The sheet formation were increased as the increase of woody core pulps contents, while the sheet strength decreased. Although the sulfomethylated pulping resulted in higher pulp yield, no morphological differences of fiber surfaces were shown as compared to the different pulping methods.

• Food Science of Animal Resources
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• v.44 no.5
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• pp.1181-1194
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• 2024

This study assessed and compared meat quality and fiber characteristics of longissimus lumborum (LL), psoas major (PM), and semimembranosus muscles among Hanwoo (HW), Jeju black (BL), and their crossbred (BH) cattle. Twelve carcasses from each breed (36 in total) were used in this study. BL and BH had higher moisture and crude ash contents and lower crude fat and protein contents than HW, regardless of the muscle type. BL had higher CIE a^*, cooking loss, and shear force values than did the other breeds for all muscle types. The muscle fiber size (cross-sectional area) of BL and BH was larger than that of HW for all muscle types. Type IIX was the dominant muscle fiber type in both BL and BH, regardless of muscle type; however, HW had the highest composition of type I compared to the other types (IIA, IIAX, and IIX) in PM. Higher total fiber density was observed in the LL and PM muscles of HW than in those of BL and BH. Meat quality and muscle fiber characteristics of BL and BH were distinct from those of HW.

• Proceedings of the Korean Society of Agricultural Engineers Conference
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• 1998.10a
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• pp.444-448
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• 1998

This paper presents the results of an experimental investigation on the compaction and compressive strength of polypropylene fiber reinforced soils. This study has been performed to obtain the physical properties of PFRS(polypropylene fiber reinforced soil) such as strain-stress relationships, OMC(optimum moisture contents) and ${\gamma}$$_{dmax}$ (maximum dry unit weight), with four different concentrations(i.e., 0.1%, 0.3%, 0.5% and 1.0% weights) of mono-filament and fibrillated polypropylene fibers. The test results indicate an appreciable increase in strength due to addition of fibers. OMC is increased with the concentration ratio of fiber, but ${\gamma}$$_{dmax}$ is decreased. From the viewpoint of strength, the fibrillated polypropylene fiber soil is more effective than the mono-filament polypropylene fiber soil.oil.

• The Korean Journal of Food And Nutrition
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• v.11 no.4
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• pp.388-393
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• 1998

This study was performed to investigate the influence of vadrious dietary fiber sources such as mugwort, apple, sea mustard, butterbur on the intestinal in aged rats. Nine groups of aged rats (12months after weanling) were fed each experimental diet containing 5% and 15% dietary fibers for 4 weeks. The contents in large intestine of aged rats used for the measurement of intestinal microflora. Total viable counts and the numbers of Bifidobacterium, Lactobacillus, Clostridium, E. coli and Staphylococcus were determined by nonselective medium and various selective media. The intake of dietary fiber sources employed did not show any differece in the number of total microorganisms, Lactobacillus and Bifidobacterium. It was remarkable that Clostridium perfringens appeared in the colon of aged rats. The prpulations of Peptococcus and Clostridium were significantly larger in the apple 5% group than in other dietary fiber groups while the number of Staphylococcus was significantly smaller in the dietary fiber groups than in cellulose group. And the Streptococcus populations decreased in the mugwort 15% group. Accordingly, the mugwort 15% group is effective in improving intestinal flora of aged rats.

• Magazine of the Korea Concrete Institute
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• v.1 no.1
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• pp.95-104
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• 1989

In order to discuss the engineering properties of carbon fiber reinforced cement composites with silica fume and silica powder, experimental studies on the CFRC were carried out. The types of fiber used which are in CFRC are PAN-based carbon fiber and Pitch-based carbon fiber. To examine the effects of types, Lengths, contents of carbon fibers and matrices, their properties of fresh and hardened CFRC were tested: According to the test results, the process technology of lightweight CFRC is developed and their optimum mix proportions are successfully proposed. Also, it can be conclueded that the reinforcement of carbon fiber is considerably effective in improving tensile strength, flexural strength, toughness and loss of shrinkage of CFRC compared with conventional mortar.

• Proceedings of the Korea Concrete Institute Conference
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• 1999.04a
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• pp.567-572
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• 1999

Experimental study was conducted to investigate the flexural-shear behavior of hooked steel fiber reinforced high strength concrete (SFRHC) beams. Twenty beams with shear span-depth ratio of 1.45 were tested, of which variables were the contents of steel fiber with aspect ratio of 60, tension reinforcement ratio and concrete compressive of 60MPa and 80MPa. Test results has shown that shear failure of the beams were changed into flexural-shear failure or flexural failure according to increasing steel fiber content, that SFRHC with slump of 15cm over and fiber volume ratio of 1.5% was possible in practice, and that proper volume ratio of steel fiber was 1.5%.

• Proceedings of the Korea Concrete Institute Conference
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• 2009.05a
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• pp.243-244
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• 2009

Fibers reinforced concrete(FRC) has abilities to make up for brittleness fracture as one of the material characteristics of concrete. However, being mixed with steed fibers in concrete mixes could set off a "Fiber Ball". The Fiber ball formation could be one of the main reasons to decrease the quality of Fibers reinforced concrete. In order to eliminate the fiber ball formation and improve the deficient flowablitiy, The necessity of research for fiber reinforced self-compacting concrete(FRC-SCC) should be raised.