• Textile Coloration and Finishing
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• v.20 no.2
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• pp.59-65
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• 2008

The tannin acid and the enzymes have been used in order to improve the ruggedness in laundry and the absorption of dyes and pigments in the textile industry for several years. The enzyme processing on the protein fiber minimizes the damage of the entire fiber and improves the dyeability by effectively modifying only the hydrophobic surface. This study tried out the structural observation by applying the Castanea crenata sieb. et. zucc. containing abundant tannin to the hair dyeing as the natural dyeing pigment along with Protease of Rhizopus sp. The dyeability was improved as compared to the dyeing using only the synthetic tanning and iron mordant. When the depth of pigment was higher in accordance with the surface observation, the enzyme dissolution had impact on dyeing and so the keratin layer on the hair surface. Accordingly, it was found that the appropriate depth was between 0.01 and 0.03%. It was estimated that 0.1% protease would treated within 30min. Consequently, it would cause the good reaction with the functional group of tannin pigment.

• Journal of the Korean Society of Clothing and Textiles
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• v.13 no.3 s.31
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• pp.187-196
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• 1989

The purpose of this study is to find at the basic data for the appropriate compressibility of the pillows for the Koreans as well as, for the appropriate conditions to establish the estimating criterion for the pillows on the market place. This paper also aim to grasp thr compressibility of the materials used to make the pillows for sale. The appropriate compressive rate of the pillows have been investigated by sensuous test. The compressive rate, recovery rate, and decreasing rate of compression and recovery have been investigated by means of ergonomic and physical experiments. The results were as follows; 1) By sensuous test, the compressive rate of the pillows for the most comfortable state turns up $45\%{\pm}5\%$ in men and women. 2) As for the compressive rate and recovery rate of the eight pillow materials on market, panya, duck feather two kinds of synthetic fiber are highest, wood is lowest. 3) The compressive rate of panya, duck feather, and two kinds of fiber is within the range of the comfort by sensuous test. 4) In the durability of the compressive rate and recovery rate against the repeated use of the pillows, duck feather is in the highest grade, panya is the lowest grade and the others are graded between two.

• Journal of the Korean Society of Food Science and Nutrition
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• v.30 no.3
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• pp.535-539
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• 2001

The modulating effect of feeding sea mustard (Undarina pinnatifida), a fiber-rich seaweed, during initiation and post-initiation phases of colon carcinogenesis was investigated in Sprague Dawley rats. Four groups of animals were exposed to the two weekly injections of a chemical carcinogen, azoxymethane (AOM). Animals were placed on diet containing 15% sea mustard during initiation. post-initiation or initiation+post-initiation phase of carcinogenesis for 10 weeks, and colonic aberrant crypt formation and cell proliferation were compared to those of rats fed semi-synthetic control diet. Results showed that sea mustard feeding significantly reduced the numbers of both aberrant crypts and aberrant crypt foci. Also, labeling indices and proliferation zones were significantly reduced in the colon of the rats fed sea mustard diets. These results indicate that the diet containing sea mustard may decrease the risk of colon cancer development, and a part of such effect may be mediated through both the blocking of initiation and the suppression of cell proliferation in the colonic crypts, although precise mechanisms should be further examined.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.25 no.11
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• pp.1104-1112
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• 2014

We present a design of the deployable lightweight antenna to be used in the satellite satisfying the required performance of the onboard sensor. The analysis is performed on the SAR antenna requirements, deploying techniques including material selection, and the characterization of deployable antenna with central disk. The performance of the solid deployable antennas and the mesh antennas are simulated, and the CFRP(Carbon Fiber Reinforced Plastics) samples are manufactured and tested. It is confirmed that the deployable antennas with central disk can meet the required performance by using deploying panels or mesh.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.26 no.2
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• pp.185-192
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• 2017

In this paper, we reviewed major design parameters for a solid type of deployable antenna and its structural design. We performed modal analysis for a single reflector panel made of aluminum and CFRP (carbon fiber reinforced plastic) to confirm the appropriateness of selected materials. We then predicted the elastic modulus of CFRP using the principles of unidirectional composite elasticity stiffness predictions such as the ROM (Rule of Mixture) and HSR (Hart Smith 10% Rule). To optimize the shape of the antenna reflector, a structural stiffness analysis was performed using derived numerical optimization factors. Six structural stiffness analyses were performed using the constructed experimental design method. The resulting optimal shape conditions are proposed to meet the structural stiffness requirements while minimizing weight.

• Korean Chemical Engineering Research
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• v.45 no.3
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• pp.264-268
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• 2007

The filtration performance of micron-sized metal fibrous filter was improved by synthesizing carbon nanotubes grown on the surface of metal fibers. The carbon nanotubes are grown with bush-like nanostructures covered around the micron-fibers or web-like nanostructures crossing between the fibers at different synthetic conditions. Filtration efficiency of CNT-metal-filter was measured and compared with the efficiency of the raw metal filter without CNTs. The developed CNT-metal-filter has higher filtration efficiency without significant difference in pressure drop compared with the conventional metal filter, which is because the carbon nanotubes function as the trap of pollutant nanoparticles.

• Journal of the Korean Society of Clothing and Textiles
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• v.31 no.7
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• pp.1119-1127
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• 2007

Nonwovens have been widely used in various regions from the households to the industrial, agricultural and medical goods. Synthetic fibers have been used for source of nonwovens commonly because of their useful and economic properties. They are not only main factor causing environmental problems but also spend huge cost to renew the environmental disruption by them. Nonwovens must have both cost-competitiveness and environment-friendly property to be the desirable sources in 21th centuries. For meet these needs, it is suitable for the times that economical and environmentally-safe kenaf fibers would be used as raw materials of nonwovens. Kenaf and polyester fibers were blended in 4 types of ratio : 0/100, 20/80, 40/60, 60/40 were needle-punched. The nonwovens properties such as color values, surface appearance, strength, elongations, stiffness, moisture regain, water and oil absorbency, and electrification were tested. As the results, tensile and tear strengths, water and oil absorbency were maximum at 20/80 kenaf/polyester blend nonwoven, because of effecting by nonwoven structure and fiber properties. The moisture regain were increased according to kenaf were blended and the eletrification reduced in proportion to the kenaf fibers by chemical property of fiber composed nonwovens.

• Journal of the Korean Geosynthetics Society
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• v.18 no.4
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• pp.243-252
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• 2019

Recently, as the utilization of underground space increases, the demand for underground excavation increases. In this study, the concrete mixture with a new material was used to develop and evaluate the stability of the CS-H wall that can greatly minimize the problems of existing wall and minimize the impact of ground depression and surrounding ground that may occur in the future for excavation of over 30 m deep in urban areas. The fiber reinforcement formulation of steel fibers, synthetic fibers, and glass fibers, along with fine aggregate parts of PS-ball and ferronickel, were mixed. The Mixture ratios were determined by conducting slump test compresive strength test, modulus of elastic test, flexural strength test, splitting tensile strength test and conductivity test. As a result of the test, the steel fiber mixture showed very good results compared to other reference values in all items, and it is considered to be the most suitable for the CS-H wall to be developed.

• Journal of Sericultural and Entomological Science
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• v.23 no.1
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• pp.56-64
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• 1981

The textile fabric contains the functions of sanitation, decoration, wearing style and washing in the practical use. Among various tetile fiber, silk has less utilities than synthetic fiber in practical use although silk has good benefits of the high quality of silk fabric. Thus no textile fiber, neither natural norsynthetic, has all the functions. In this sense, many compound fabrics have been improved to reveal various functions of fabric However, this has been disturbed with the problem of dyeing, expecially in the case of compound fabric of silk. The work is carried out to improve the dyeing method of compound fabric of polyester and silk. The results obtained are as follows: 1. In the dyeing of compound fabric(P/S fabric), azo dyes was more suitable than anthraquinone dyes. 2. According to the carrier, dyeing spot was appeared by the high concentration in bath. 3. Degree of dye fixation was decreased in dyeing of methylnaptharine carrier(D.N) and anion disperser(T.S). 4. The affinity of dye was suitable in the dyeing bath of azo dye, trichlorobenzene carrier and nonion disperser. 5. Dye fixation of silk side in compound fabric by acid dye showed higher in acid bath of dyeing. 6. In printing of silk and polyester compound fabric, it must be understood relationship among fibers, dyes, and steaming conditions.

• The Journal of Natural Sciences
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• v.8 no.1
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• pp.145-151
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• 1995

The stretching of synthetic fibers by hot dry process is very difficult, because these fibers have high glass transition temperature at above $150^{\circ}C$. But, we used a swell-wet stretching precess; the fibers are stretched in a swelling agent such as organic solvents at lower temperature. In this study, 100% acryl fibers were uniaxially stretched with free width at $70^{\circ}C$ by swell-wet process in organic solvents. The stretchability was estimated by stretching work. This work is concerned with stretching stress and strain, and initial modulus. We found that it is a good parameter for the estimatation of high strength to the acrylic fiber. The effects of stretching conditions on the molecular orientation for high strength and mechanical properties of PAN fibers were measured.