• Proceedings of the KIEE Conference
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• 1997.07d
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• pp.1577-1578
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• 1997

We have studied the effect of the rubbing fabric for liquid crystal alignment and pretilt angle generation in nematic liquid crystals (NLC), 4-cyano-4-n-penthylbiphenyl (5CB), on rubbed polyimide (PI) surfaces. The pretilt angle of 5CB for nylon and rayon fabric is larger than that of cotton fabric in weak rubbing on rubbed PI surfaces. We conclude that the pretilt angle of 5CB is strongly related to the rubbing fabrics on rubbed PI surfaces.

• Proceedings of the Korean Geotechical Society Conference
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• 2000.09a
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• pp.81-92
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• 2000

Green Slope(F.F.R : Fabric Form Reinforcement Method) is one of an environmental slope protection method at steep cutting sites. This method is that soil and rock at the steep slope is fixed using the environmental Fabric Form, Nail, Rock Bolt and Rock Anchor, And then, the surfaces covered with grasses or weeds. This method will be satisfied both safe slope protection and natural environment appearance. Green Slope is a useful method of the construction sites of steep cutting slopes.

• Proceedings of the KSR Conference
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• 2010.06a
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• pp.557-563
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• 2010

Mode II interlaminar fracture toughness was measured and fractured surfaces were observed of carbon/epoxy and glass/epoxy woven fabric composites for carbody structure. Woven fabric carbon/epoxy and glass/epoxy composites that made with prepreg and epoxy resin(RS1222) are used in carbody structure of Korean tilting train(TTX) and low floor bus. ENF(End Notched Flexure) specimens having $120mm{\times}20m{\times}5mm$ shape and 35mm initial crack were made with each composites and three point bending tests according to ASTM D790 were conducted for these specimens. Crack lengths in tests were recorded using optical microscope and digital camcorder. NL(Non Linear), 5% offset and Max. load points in load -displacement curves were checked and mode II interlaminar fracture toughness of these points were calculated and compared. Fractured surfaces of specimens were observed using optical microscope and mode II delamination behavior of each composites was discussed.

• Journal of the Korean Society of Clothing and Textiles
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• v.20 no.5
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• pp.905-914
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• 1996

To study the effect of the bleaching agents in detergents on the degradation of cotton fabrics, the carboxyl contents, copper numbers, degree of polymerization, the change of tensile strengths and fiber surfaces of cotton fabric before and after washing were examined. The results obtained were as follows: As the cycles and temperature of washing increased, the carboxyl content of washed cotton fabric changed little but the copper unmber of cotton fabric was increased. At 6$0^{\circ}C$ , 8$0^{\circ}C$ the copper number of cotton fabric washed with soidum perborate (PB) was higher than that of with sodium percarbonate (PC). The degree of polymeriazation and tensile strength of cotton fabric were decreased and at higher temperature those were more decreased but were less decreased when tetraacetyehylenediamine (TAED) was added. The degree of polymerization had negative relation with copper unmber but with tensile strength of cotton fabric had positive relation. Cotton fiber surface was more degraded by bleaching agents and hydrogen peroxide exhaustion was increased as the temperature of washing increased. And hydrogen peroxide exhaustion had negative relation with the degree of polymerization.

• Fashion & Textile Research Journal
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• v.15 no.3
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• pp.461-466
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• 2013

Synthetic fiber materials were developed due the desire of consumers for high-quality, high-performance and comfort. A high functionality of synthetic fiber can be obtained through surface treatment that can improve hydrophilic properties, color depth after dyeing and adhesion properties. These advantages create added-value. Hydrophobic properties are an important feature to create added-value (such as hydrophilic properties). One side processing is a method of imparting to contrary function on the front and rear side. In this study, fluorine-coated Nylon/PU blended fabric was treated on only one side with a low-temperature plasma treatment; subsequently, the contact angles decreased by increasing the time and intensity of the plasma treatment. The contact angle of the untreated surface and the treated surface was different. It a showed a difference in the properties of both surfaces. Tensile strength and stiffness decreased by increasing the time and intensity of the plasma treatment. However, plasma treatment did not significantly change the tensile strength and stiffness on both surfaces of the fabric. SEM photographs showed the surface of fluorine-coated fabric and the etching surface by using plasma treatment on the fabric. Plasma treatment was confirmed not to affect the physical properties of the fabric.

• Korean Journal of Metals and Materials
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• v.49 no.10
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• pp.760-765
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• 2011

This paper presents a study of the tensile behavior of carbon and glass fiber reinforced epoxy hybrid laminates manufactured by vacuum assisted resin transfer molding (VARTM). The objective of this study was to develop and characterize carbon fiber reinforced plastic hybrid composite material that is low cost and light-weight and that possesses adequate strength and stiffness. The effect of position and content of the glass fabric layer on the tensile properties of the hybrid laminates was examined. The strength and stiffness of the hybrid laminates showed a steady decrease with an increase of the glass fabric content this decrease was almost linear. Fracture strain of these laminates showed a slight increasing trend when glass fabric content was increased up to 3 layers, but at a glass fabric content > 3 layers the strain was almost constant. When glass fabric layers were at both outer surfaces, the hybrid laminate exhibited a slightly higher tensile strength and elastic modulus due to the small amount of glass yarn pull-out.

• Korean Journal of Veterinary Research
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• v.43 no.4
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• pp.703-708
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• 2003

This study was carried out to compare the efficacy of carboxymethyl chitosan fabric (CMCF) with that of the combination of low molecular weight heparin (LMWH) and CMCF for the prevention of postoperative adhesions in the rat. Adhesions were induced by suturing both the ileal serosa and peritoneum scraped until petechial bleeding occurred. CMCF were sutured between two surfaces, and LMWH were instilled intraperitoneally immediately before closure of the peritoneomuscular layer. The adhesions were blindly assessed 2 weeks later by using a tensiometer. The mean tensile strength(Newton) of formed adhesions was $2.59{\pm}0.85$ in control group, $2.10{\pm}0.75$ in the CMCF group and $1.53{\pm}0.44$ in the CMCF+LMWH group. The most favorable prevention against adhesion was achieved in the CMCF+LMWH group. Therefore, we could conclude that CMCF+LMWH were effective in prevention against postoperative adhesion in the rat.

• Proceedings of the Korean Society For Composite Materials Conference
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• 2005.11a
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• pp.256-259
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• 2005

Mixed-mode interlaminar fracture toughness of carbon fabric/epoxy composites, which are applicable to tilting train carbody, was evaluated through the MMB (Mixed-mode bending) test. Specimens were made of CF3327 plain woven fabric with epoxy and a starter delamination at one end was made by inserting Teflon film with the thickness of 12.5 μ m. Mixed-mode interlaminar fracture test was conducted for 6 types of specimens with the mode II ratio of 20 ,35, 50, 65, 80, 90%. Also crack propagating behaviors and fractured surfaces were examined through an optical travelling scope and a scanning electron microscope, respectively.

• Journal of the Korean Society for Railway
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• v.8 no.2
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• pp.195-201
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• 2005

Mode II interlaminar fracture behaviors of carbon fabric/epoxy composites, which are applicable to tilting train carbodies, was investigated by the ENF (End notched flexure) test. The specimens were made of CF3327 plain woven fabric with epoxy and a starter delamination at one end was made by inserting Teflon film with the thickness of 12.5$mu$m or 25.0$mu$m. The equation for mode II interlaminar fracture toughness was suggested based on the effective crack length from the compliance of load-displacement curve. Mode II interlaminar fracture toughness was evaluated for several types of the specimens. Also crack propagating behaviors and fracture surfaces were examined through an optical travelling scope and a scanning electron microscope.

• Proceedings of the Korean Society of Dyers and Finishers Conference
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• 2009.03a
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• pp.110-111
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• 2009

A solution containing 3-Mercaptopropyltr-imethoxysilane(MPTMS) was employed to modify surface of cotton fabrics with a silver colloid. Silver nanoparticles were applied on cotton fabrics via treatment with 3-MPTMS. The rate of silver nanoparticles on the fabric surface were measured with Energy Dispersive Spectroscopy(EDS). EDS results confirm the silver atom on the cotton surface.