• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.32 no.3
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• pp.17-21
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• 2004

Tape-wrapped structures have been generally used in nozzle parts of guided missiles. A continuous band of woven composite material is wrapped around a mandrel that is designed to produce real products. After going through a vacuum bagging process, this woven composite material is cured in a high-pressure autoclave or hydroclave. However, tape-wrapped structures are difficult to analyze because of its large thickness and inclined lay-up. The present study investigates the method of analysis and failure prediction of tape-wrapped structures. The four-point bending test and its finite element analysis were performed to study how to model tape-wrapped structures and investigate their failure characteristics.

• The Research Journal of the Costume Culture
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• v.29 no.5
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• pp.735-746
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• 2021

Uiwon-gun (1661-1722) and Sim Ikchang (1652-1725) were people of the upper classes of the Joseon Dynasty, who's belts woven with thread were found in their graves. The purpose of this study is to find a term suitable for the belts of these two people and to reveal the characteristics of the two belts and decipher the 8-character text marked on Shim Ikchang's belt to understand its meaning. The terms used during the Joseon Dynasty related to woven belts include "Gwangdaho", "Daeja", "Bunhapdae", "Sagagda", "Bangseungah", and "Samunjikdae". Among these terms, "Gwangdahoe" is the most suitable to indicate the belts of for both belts. The belts are made of a silk fabric of narrow width. The size of Uiwon-gun's belt is 2.8×199cm, and because it is folded in half lengthwise and sewn, the original width is 8cm. It was woven in the imitation gauze technique. Sim Ik-chang's belt measures 10.5×258cm and is decorated with a woven net at the end. There are water and mountain patterns on both ends of the belt, with 11 lines of flower patterns equally spaced between. The belt is damask, the inscription part is made of brocade with letters expressed in golden thread. The meaning of the inscription is "Made in Hanbu. May you live a long and healthy life".

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2006.04a
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• pp.15-20
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• 2006

Real time health monitoring system was studied to detect the . generation of defects in the composite structures during service life. The PZT sensors were embedded into the woven-glass/phenol composite plate during the fabrication. VARTM (Vacuum Assisted Resin Transfer Molding) process were used to fabricate the composite plate. A Teflon tape was embedded between glass fiber layers to mimic delamination induced during service. Normalized maximum amplitude and energy analyses were used for the acquired signals. Both amplitude and energy of acquired signals were extremely sensitive to the delamination. Therefore, it was successful to detect and to locate the defects in composite plate by monitoring signals from sensors and using the proposed method.

• Journal of the Korean Society of Safety
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• v.34 no.6
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• pp.1-6
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• 2019

Carbon fiber has excellent specific strength, corrosion resistance and heat resistance. And p-Aramid fiber has high toughness and heat resistance and high elasticity, and is used in various fields such as industrial protective materials, bulletproof helmets and vests, as well as industrial fields. However, carbon fiber is relatively expensive, and is susceptible to brittle fracture behavior due to its low fracture strain. On the other hand, the aramid fiber tends to decrease in elastic modulus and strength when applied to the epoxy matrix, but it is inexpensive and has higher elongation and fracture toughness than carbon fiber. Thus the twill hybrid carbonaramid fiber reinforced composite laminate composite was investigated for a delamination fracture toughness under Mode I loading by 2 kinds of MBT and MCC deduction. The specimen was fabricated with 20 hybrid fabric plies. The initial crack was made by inserting the teflon tape in the center plane with a₀/W=0.5 length. The results show that SERR(Strain Energy Release Rate) as the critical and stable delamination fracture toughness were 0.09 kJ/㎡, 0.386 kJ/㎡ by MBT deduction, and 0.192 kJ/㎡, 0.67 kJ/㎡ by MCC deduction, respectively.