• Proceedings of the Korean Society of Precision Engineering Conference
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• 2004.05a
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• pp.56-56
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• 2004

섬유강화 복합재료는 응용범위가 산업계 전반으로 빠르게 확대되고 있다. 개발 초기에는 하중을 감당하지 않는 이차 구조물에 주로 사용되어 왔으나, 점차 산업 전반의 I차 구조물(Primary Structure)에 쓰이는 등, 그 사용범위가 넓어지고 있으며, 취약한 두께방향 물성 향상의 필요성을 충족시키기 위해 다축경편(MWK) 복합재료에 대한 연구가 진행되고 있다. 본 논문에서는 다축경편(MWK) 복합재료의 기계적 체결부에 관한 응력해석을 연구하였다.(중략)

• Proceedings of the Korean Society of Dyers and Finishers Conference
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• 2011.03a
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• pp.87-87
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• 2011

파일 직물은 높은 기공성과 유체흡수 및 보온성이 뛰어나, 타월, 행주와 같은 청소직물 뿐 아니라 침장 및 의류용 소재에도 널리 사용되고 있다. 최근 경편분야에서 극세사를 이용한 제품이 다양한 용도로 적극 활용되고 있으며 환편 제품으로 가볍고 터치감이 특징인 Polar Fleece가 저렴한 가격으로 소비자들의 관심이 증대되고 있다. 이러한 소비시장을 고려해 볼 때 이 두 가지가 함께 공존하는 제품 개발이 절실하지만, 극세사 제품은 트리코트 경편제품이고 Polar Fleece로 활용하는 제품은 환편에서 후가공 기술을 응용한 제품으로 생산기계와 가공공정이 다르며, EF Velboa와 Polar Fleece 2종류 원단의 본딩으로만 가능하기 때문에 환경적으로도 유해하다. 이에 본 연구에서는 덕산엔터프라이즈(주)에서 경편조직과 원사의 특성을 고려하여 본딩 공정없이 표면 은 EF-Velboa, 이면은 Polar Fleece와 같은 부드럽고 고급스러운 외관을 동시에 발현하는 3D 입체구조를 가진 원단을 개발하였다. 또한 개발된 원단의 다양한 용도전개를 위해 염색프로그램, 균염성, 견뢰도 테스트를 진행하였으며 향후 제품군으로의 활용 가능성 여부를 검토하였다.

• Proceedings of the Korean Society For Composite Materials Conference
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• 2002.10a
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• pp.280-283
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• 2002

In the manufacturing of large scale composite structures, the cost-effective processing and the enhancement of structural performance are critical. One of the most effective ways for this purpose is to use stitched multiaxial warp knitted (MWK) perform in the resin transfer molding process. This study reports the effect of stitching on the mechanical properties of MWK composites, and the feasibility processing of the thick U-beam structure utilizing the stitched preforms. Permeability of the preform, viscosity and cure property of the epoxy resin have been measured. The results of resin flow analysis has been used in determining the gate/vent locations of the RTM mold. Cross-sectional observation of the channel beam prototype demonstrated that the resin impregnation was almost complete, except for some surrounding area of stitched yarns.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.41 no.6
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• pp.704-709
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• 1996

This experiment was carried out to establish the system of mass propagation through tissue culture using sucker and stem in Ramie. The sterilization for tissue culture of Ramie was the better treatment of 2% NaClO for 20 minute into ultrasonic cleaner than the others, and so rate of contamination was 3.3%, and it was able to produce 96% healthy plant. The effect of growth regulator was superior to mixed treatment of 0.02mg/$\ell$ NAA, 1.5mg/$\ell$ BA, 0.lmgmg/$\ell$ GA$_3$, which it was not formed callus and but produced 96% healthy plant. The effect of propagation was higher in culturing of the stem node than the sucker in cultural part, local variety than improved ones. The effect of acclimatization was superior to pretreatment of 30 minute after soaking in 100ppm NAA, transplanting on bed soil which mixed to ratio of vermiculite : soil : sand =1 : 2 : 1, the transplanted plants were grown all normal.

• Proceedings of the Korean Fiber Society Conference
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• 2007.11a
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• pp.343-344
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• 2007

• Proceedings of the Korean Society of Dyers and Finishers Conference
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• 2008.10a
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• pp.109-110
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• 2008

본 연구에서는 신축성이 우수한 친수형 무공 PET필름을 사용해서, 소취성, 보온성 및 투습방수성이 우수한 신발용 소재를 개발하였다. 이상의 목적을 달성하기 위해서 최적 소재의 선정, PET필름의 특성평가, 최적 라미네이팅 공정조건 확립, 첨가제 선정 및 가공조건 확립 등에 대해서 실험고찰을 하였으며, 얻어진 주요 결과는 다음과 같다. (1) 신발의 갑피용 및 안창용 최적소재로서 경편직물을 선정하였으며, PET필름의 최적 요구특성은 내수성 9460mmH2O, 투습성 10,000g/m2/24hrs, 인장강도42kgf/cm2, 신도249% 였다. (2) Hot-melt 라미네이팅 공정에서의 투습방수성을 좌우하는 Dot roll No, Coating gap의 최적조건은 CP75(Engraved dot roll no), -0.2mm(Coating Unit gap) 였다. (3) EVA base polymer 및 기타 조제의 최적 배합비를 확립하고 이를 바탕으로 compound를 제조하여 Press로 molding하여 안창용 Sponge를 얻었다. (4) 안창 sponge 위에 점착된 knit 소재의 소취효과는 우수하였으며, 갑피용 투습방수 경편직물의 보온성도$15{\sim}20%$로 우수하였다.

• Fashion Information and Technology
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• v.3
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• pp.13-23
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• 2006

• Proceedings of the Korean Society For Composite Materials Conference
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• 2005.04a
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• pp.125-129
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• 2005

A micromechanical model for predicting the elastic constants of stitched multi-axial warp knitted (MWK) composite is developed. The averaging method is used to obtain effective properties of stitched MWK fabric composites. In the analysis, a representative volume of the MWK fabric composite is identified. The geometric limitations, effects of stitching yarns and design parameters of MWK fabric composites are considered in the model. Then, the elastic properties of stitched MWK fabric composites are predicted. Finally, the predicted elastic constants are validated by comparison with experimental data. The predicted results are in fair agreement with the experimental results.

• Proceedings of the Korean Society For Composite Materials Conference
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• 2004.10a
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• pp.198-202
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• 2004

An analytical model using expanded bridging model was proposed to predict the elastic properties and behaviors of stitched multi-axial warp knitted (MWK) fabric composites, The characteristics of MWK fabric composites are the assemblage of multi-layers of fiber bundles for in-plane reinforcement and stitch yams for the through-the-thickness reinforcement. In the analysis, a representative volume of the MWK fabric composite was identified, The geometric limitations, effects of stitching yams and design parameters of MWK fabric composites were considered in the model. Then, the elastic properties and behaviors of MWK fabric composites were predicted, Finally, the results of proposed model of the composites were verified through the experiments, The predicted results were in fair agreement with the experimental results

• Proceedings of the Korean Society For Composite Materials Conference
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• 2004.04a
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• pp.246-249
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• 2004

When MWK (Multiaxial Warp Knitted Fabric) composites are applied for the structures, the connections of each component using mechanical fastening is needed. The local contact between the bolted joint and the composite laminates may induce high stress concentration or breakdown in the laminates for the mechanical joints. There for, it is strongly required to study the characteristics of mechanically joints of MWK composite laminates. In this study, stress analysis near the hole boundary of MWK composite laminate is conducted with various geometric factors under different loadings. In the case of multi-pin loaded MWK composite laminates, the results show that the types of loadings and geometric factors of mechanical joints have a significant influence on the joint performances.