• Proceedings of the Korean Society For Composite Materials Conference
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• 2000.11a
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• pp.183-186
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• 2000

A new textile metal matrix composite fur electronic packaging was developed and characterized. The thermal management materials consist of a plain woven carbon fabric as reinforcement and pure aluminum as matrix. The finite element method has been utilized in the analysis of thermal stress between the constituent components of packaging. The prototype part was manufactured by the liquid pressurizing method. The composite has CTE values of 4 to $5{\times}10^{-6}\;^{\circ}C^{-1}$10 in the range of $25^{\circ}C$ ~ 175$^{\circ}C$, resulting in good agreement with electronic materials such as Si and GaAs.

• Journal of the Korean Ceramic Society
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• v.50 no.6
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• pp.378-383
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• 2013

Continuous fiber-reinforced ceramic matrix composites (CFCCs) have a complex distribution of porosity, consisting of interfiber micro pores and interbundle/interply macro pores. Owing to the complex geometry of the pores and fiber architecture, it is difficult to obtain representative microstructural features throughout the specimen volume with conventional, destructive ceramographic approaches. In this study, we introduce X-ray computed microtomography (X-ray ${\mu}CT$) to nondestructively analyze the microstructures of disk shaped and tubular $SiC_f$/SiC composites fabricated by the chemical vapor infiltration (CVI) method. The disk specimen made by stacking plain-woven SiC fabrics exhibited periodic, large fluctuation of porosity in the stacking direction but much less variation of porosity perpendicular to the fabric planes. The X-ray ${\mu}CT$ evaluation of the microstructure was also effectively utilized to improve the fabrication process of the triple-layered tubular SiC composite.

• Journal of the Korean Society of Costume
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• v.36
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• pp.53-75
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• 1998

The kind, the structure, and the motif of the Chosun dynasty's fabrics found mainfy within the Buddhist statues were studied. The total of 62 pieces of fabrice can be classified chronologically as follows ; 27 pieces in the year of 1431, 20 pieces of 1550, 9 pieces of 1664, and 6 pieces of 1735. These 62 fabrics also categorized by the weaving method as follows; 27 plain weaved, 17 twill weaved, 10 pieces of satine weaved, 7 pieces of Leno weaved, and 1 piece of double weaved fabrics. Most of the studied fabrics were silk, the rest were 2 pieces of yam and 1 piece of cotton, Kyun, Chu, and Cho were the plain weaved silk as Nung and Ki were the twill weaved silk, Satine weaved silk was called as Dan and double weaved silk was called Chikum in the Chosun dynasty. 1. The antique fabrics were composed of mainly silk. This is believed due to the utmost devotion to the buddhist statue as an object of worship. 2. In the fabric's structural point of view, th ecrossed 4-ply threads of warp yarn which is one of Leno weaved can be observed fre-quently in the period of Korea dynasty's fabrics. But it started to disappear in the beginning of Chosun dynasty, since only one piece of Ra could be found in the 1431's fabrics. Keum, one of the double weaved structure is assumed to be extinct from the Korea dynasty. Satin weaved fabrics started to be woven from the latter period of Korea dynasty and was very popular in Chosun dynasty. 3. The widths of fabrics in the Chosun dynasty gradually decreased compared with those of Korea dynasty.

• Journal of the Korea Fashion and Costume Design Association
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• v.12 no.2
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• pp.131-138
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• 2010

The purposes of this study are for current manufacturing status of the formal knit slacks for the middle aged women. As for the methodology, five manufacturers specializing in formal knitwear brands were subjected to the study, to examine the current manufacturing status of the knit slacks for the middle aged women, by conducting interviews and questionnaire with patterner and designer. The questionnaire items are 20 ones including general questions on manufacturing of the knit slacks, questions on materials used in manufacturing, and on sewing. The results are as followings : First, as for the manufacturing structure of the knit slacks manufacturer, all manufacturers directly manufactured knit slacks in their own factory, and the manufacturing was comprised of 10% in woven slacks and 90% in knit slacks. Second, as for the type of yarn mostly used in fabric knitting for the knit slacks, wool was used mostly for F/W, and acrylic or Saint yarn for S/S. As for the types of knit, Milano rib stitch and Half Milano rib stitch were used for wool and acrylic knitting, and plain stitch was used for Saint yarn. As for the gauge, 12G and 14G were used, whereas 7G, 12G was used for Saint yarn. Repair requests of the knit slacks were mostly on the length of the pants, such as shortening hip circumference and crotch length, or widening waist and hip area. The study shows that the size of knit slacks did not fit the body type of customers.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.36 no.10
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• pp.1261-1266
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• 2012

In this study, salt-water immersion tests were experimentally performed for up to 12 months to investigate the hygrothermal effect of salt-water environments on the mechanical properties of carbon/epoxy composites. The composites were manufactured by laminating prepregs composed of carbon plain-woven fabric and epoxy resin. The specimens were subjected to temperatures of 35, 55, and $75^{\circ}C$ while being exposed to the salt-water environments. Mechanical test results showed that the tensile modulus and tensile strength decreased at a small rate, and the compressive modulus and compressive strength decreased at a relatively larger rate, as the exposure temperature and time increased. The rate of decrease in compressive strength became larger as the exposure temperature became higher. This is because a higher environmental temperature accelerates the salt-water uptake; this, in turn, reduces the compressive strength more rapidly.

• Science of Emotion and Sensibility
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• v.21 no.1
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• pp.99-114
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• 2018

Saekdong is a unique Korean fabric that has been used since ancient times, and it is woven with the plain or satin weave so that vertical stripes appear by various colored warp threads of equal spacing. Saekdong means pleasure, joy, serenity, heavenly blessing, spirituality, wind, and abundance, expressing the optimistic and positive sentiment of Korea's forefathers. This study investigated how ancient Saekdong occurred with meanings. As a research method, this study used literature review and surfing newspapers and photographs, museum and internet search, even from other fields such as earthenware, bronze, and traditional dance. We collected Saekdong and the lifestyles of ethnic Koreans living in China, investigated the Asuka culture of Japan, and the tomb murals of Takamatsu-Chong, which are Baekje and Goguryeo settlement areas. The results are as follows: First, it expresses happy occasion, pleasure, and joy, and expresses a desire for good things to be repeated and lasting. Second, it symbolizes simple beauty, order, equality and harmony of many tribes. Third, Saekdong is life and power which represent a sacred, heavenly, mysterious bird. Fourth, it symbolizes abundance and wealth, rain, wind or fields. Finally, this study showed the brilliance and pride of Korean hanbok through Saekdong. The significance of this study is to examine the symbolism and inherent aesthetic characteristics of Saekdong and to show the unique value and spiritual heritage of the Korean people.

• Composites Research
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• v.20 no.5
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• pp.64-69
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• 2007

Matrix dominant properties of composites are largely degraded under harmful environments such as temperature and humidity. Therefore we should consider the harmful environmental factors in the design of an UAV integral fuel tank subjected to high temperature and high humidity. The harmful environment experiment was performed for carbon/epoxy composites made of a unidirectional prepreg USN175B, and a plain woven fabric prepreg WSN3. The immersion experiment was performed under $90^{\circ}C$. The specimens were tested when the weight gam of specimen was saturated. The specimens were tested under $74^{\circ}C$ to obtain tensile and inplane shear properties. The results showed that the matrix dominant properties were extremely degraded by hygrothermal environment. To consider the variability of load, the anti-optimization method was applied. By using this method, the worst load case was found by comparing the load convex model and stability boundary. The stability boundary was obtained by analysis of the integral wing fuel tank of UAV using degraded properties. To do this, it was known that the worst load case of the integral wing fuel tank was the hovering mode load case.