• Journal of the Korea Fashion and Costume Design Association
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• v.13 no.3
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• pp.165-175
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• 2011

In this study, document research on Jogakbo and Tosi were carried out and textile designs were developed by applying Jogakbo and Tosi together for motives. The purposes of this study were to develop a unique textile design, and then to enhance the competitiveness of Korean textile industry in the world market and pass down a Korean traditional fiber art cultural legacy. The results are as follows; First, the title of textile design was decided to "innocence of childhood" and the concepts are "sim ple heart ed, pure heart, sweet", in order to develop textile design for the young generation Second, Motives were chosen Jogakbo and Tosi to reflect Korean traditionality and identity and textile designs were expressed on ground fashion trends for modernity. Third, developed textile designs were printed with digital printing method for eco-friendly and productivity, and various articles clothing, nectie, shoes, bag, bedings were producted with developed fabrics for multipurpose. Forth, the developed textile designs were evaluated highly in point of Korean traditionality and identity, felling of simplehearted, pure hear and sweet, modernity and fashion trend, and preference by a sensory test of developed test design.

• Fibers and Polymers
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• v.4 no.1
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• pp.20-26
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• 2003

The thermal behavior, morphology, ester-interchange reaction of Poly(trimethylene terephthalate) (PTT)/poly(ethylene terephthalate) (PET) melt blends were investigated over the whole composition range(xPTT/(1-x)PET) using a twinscrew Brabender. The melt blends were analyzed by differential scanning calorimetry (DSC), nuclear magnetic resonance spectroscopy ($^{13}{C-NMR}$), and scanning electron microscopy (SEM). Single glass transition temperature ($T_g$) and cold crystallization temperature ($T_cc$) were observed in all melt blends. Melt blends were found to be due to the ester-interchange reaction in PTT/PET blend. Also the randomness of copolymer increases because transesterification between PT and PET increases with increasing blending time This reaction increases homogeneity of the blends and decreases the degree of crystallinity of the melt blends. In PTT-rich blends, mechanical properties decrease with increase of PET content compared with that of pure PTT. And, in PET-rich blends, tensile modulus decreases with increase of PTT content, but tensile strength and elongation is similar to that of pure PET.

• Carbon letters
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• v.5 no.4
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• pp.159-163
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• 2004

The polymer-ceramic hybrid, known as 'ceramer', was synthesized by a sol-gel process by incorporating different amount of alkoxide as source of silicon in resorcinol-formaldehyde in presence of basic catalyst to get different percentage of silicon in ultimate carbonized composites. FTIR of the ceramer confirms that it is a network of Si-O-Si, Si-O-$CH_2$ and Si-OH type groups linked with benzene ring. Different amount of silicon in the ceramer exhibits varying temperature of thermal stability and lower coefficient of thermal expansion as compared to pure resorcinol-formaldehyde resin. The lower value of CTE in ceramer is due to existence of silica and resorcinol -formaldehyde in co-continuous phase. Unidirectional composites prepared with ceramer matrix and high-strength carbon fibers show lower value of flexural strength at polymer stage as compared to those prepared with resorcinol-formaldehyde resin. However, after heat treatment to $1450^{\circ}C$, the ceramer matrix composites show large improvement in the mechanical properties, i.e. with 7% silicon in the ceramer, the flexural strength is enhanced by 100% and flexural modulus value by 40% as compared to that of pure resorcinol-formaldehyde resin matrix composites.

• Asian-Australasian Journal of Animal Sciences
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• v.12 no.7
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• pp.1063-1069
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• 1999

Wheat straw samples (3-4 cm) were sprayed with solutions of urea (U) alone or with a dry addition of garden soil (GS), midden soil (MS), soya bean meal (SM) or jack bean meal (JM) as crude urease sources and with a pure urease (UR) enzyme. Each of the urease sources was included at two levels: 30 and 60 g/kg except pure urease, which was added at a level of 2.5 & 5.0 g/kg treated straw dry matter. Untreated straw without urease source was used as a control. After treatment, samples were sealed in polythene bags and stored for 2, 7, 14, 21 and 35 days at $19{^{\circ}C}$. The urease sources, their levels and treatment time produced significant effects on ammonia production (p<0.01). The addition of urease offered more flexibility in hydrolyzing urea in the shortest possible time. Incorporation of soya bean and jack bean meal was effective in reducing the modified acid detergent fiber (MADF) content of straw and the same time increasing organic matter (OM) digestibility. Overall effect, addition of soya bean to urea at a ratio of 1:1 appeared to be the most satisfactory urease source for the treatment of urea and wheat straw.

• Carbon letters
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• v.13 no.4
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• pp.230-235
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• 2012

In this study, reduced graphene oxide/polyimide (r-GO/PI) composite films, which showed significant enhancement in their electrical conductivity, were successfully fabricated. GO was prepared from graphite using a modified Hummers method. The GO was used as a nanofiller material for the preparation of r-GO/PI composites by in-situ polymerization. An addition of 20 wt% of GO led to a significant decrease in the volume resistivity of composite films by less than nine orders of magnitude compared to that of pure PI films due to the electrical percolation networks of reduced GO created during imidization within the films. A tensile test indicated that the Young's modulus of the r-GO/PI composite film containing 20 wt% GO increased drastically from 2.3 GPa to 4.4 GPa, which was an improvement of approximately 84% compared to that of pure PI film. In addition, the corresponding tensile strength was found to have decreased only by 12%, from 113 MPa to 99 MPa.

• Structural Engineering and Mechanics
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• v.30 no.2
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• pp.211-223
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• 2008

A number of studies have suggested that the use of high ductile and high shear materials, such as Engineered Cementitious Composites (ECC) and High Performance Fiber Reinforced Cementitious Composites (HPFRCC), significantly enhances the shear capacity of structural elements, even with/without shear reinforcements. The present study emphasizes the development of a nonlinear model of shear behaviour of a HPFRCC panel for application to the seismic retrofit of reinforced concrete buildings. To model the shear behaviour of HPFRCC panels, the original Modified Compression Field Theory (MCFT) for conventional reinforced concrete panels has been newly revised for reinforced HPFRCC panels, and is referred to here as the HPFRCC-MCFT model. A series of experiments was conducted to assess the shear behaviour of HPFRCC panels subjected to pure shear, and the proposed shear model has been verified through an experiment involving panel elements under pure shear. The proposed shear model of a HPFRCC panel has been applied to the prediction of seismic retrofitted reinforced concrete buildings with in-filled HPFRCC panels. In retrofitted structures, the in-filled HPFRCC element is regarded as a shear spring element of a low-rise shear wall ignoring the flexural response, and reinforced concrete elements for beam or beam-column member are modelled by a finite plastic hinge zone model. An experimental study of reinforced concrete frames with in-filled HPFRCC panels was also carried out and the analysis model was verified with correlation studies of experimental results.

• Macromolecular Research
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• v.17 no.8
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• pp.597-602
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• 2009

Although the existing design principle of full-sequence ionic complement is convenient for the development of peptides, it greatly constrains the exploration of peptides with other possible assembly mechanisms and different yet essential functions. Herein, a novel designed half-sequence ionic complementary peptide (referred to as P9), AC-Pro-Ser-Phe-Asn-Phe-Lys-Phe-Glu-Pro-$NH_2$, is reported. When transferred from pure water to sodium chloride solution, P9 underwent a dramatic morphological transformation from globular aggregations to nanofibers. Moreover, the rheological experiment showed that the P9 could form a hydrogel with a storage modulus of about 30 Pa even at very low peptide concentration (0.5% (wt/vol)). The P9 hydrogel formed in salt solution could recover in a period of about 1,800 sec, which is faster than that in the pure water. The data suggestcd that the half-sequence, ionic complementary peptide might be worthy of further research for its special properties.

• Journal of Fashion Business
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• v.5 no.1
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• pp.117-130
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• 2001

The purpose of this research focuses mainly on the establishment of: the image of the police that can be adopted to meet the demands of reality through the development of the design of policewomen's uniform in the times that require reestablishment of the image of the police; the image of the police that is appropriate for the organic structure of the society; and the image of the police that cooperate with the citizens. For background research I have considered the police and their uniforms from a theoretical point of view and have examined the process by which Korean policewomen's uniforms have changed. Actual research was carried out policewomen of Seoul Regional Police Station, was conducted and the results were utilized to figure out what the problem was. This research suggests an improvement measure by making four suits of summer and spring-and-autumn work-uniforms, and six suits of spring-andautumn and winter full-dress uniform. First the colors of work-uniforms and full-dress uniforms are not blue, which incites a feeling of coldness and stiffness, but are colors that are feminine and emit warmth---red, ivory, khaki, black, and beige. second pure, natural fiber is difficult to wash and is not an appropriate material for policewomen's uniforms when considering its cost and etc., fabrics that are a mix of synthetic fiber and natural fiber were chosen. Because mixed fabrics are cheaper and their ability to maintain shape is superior to that of natural fiber, mixed fabric is an appropriate material for policewomen's uniforms. third the feminine image of policewomen was considered; therefore, masculine image, which is rigid and strong, was avoided and the image was expressed in a serene and beautiful way. Also slim line was added to the current uniforms to emphasize feminine beauty. The conclusion of this study is that police officers in the 21st century want to be seen as the citizens cane and benevolent volunteers that live together with the citizens, not as suppressive and powerful people.

• Elastomers and Composites
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• v.54 no.4
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• pp.345-350
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• 2019

In this study, aliphatic polyketone (PK)/chopped carbon fiber (CCF) composites with various CCF contents were prepared using a modular intermeshing co-rotating twin screw extruder, and their mechanical and thermal properties such as tensile, flexural, and impact strength and thermal conductivity were investigated. The amount of CCF was increased from 0 to 50 wt%. The tensile and flexural strength of the PK/CCF composites increased as the CCF content increased, but the elongation at break and impact strength was lower than that of pure PK. Thermal properties such as heat distortion temperature and thermal conductivity increased as the CCF content increased. Morphological observations revealed that fiber orientation and interface adhesion between the PK and the CCF in the PK/CCF composites were formed due to the twin screw extrusion, which contributed to improving the mechanical and thermal properties of the composites.

• Computers and Concrete
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• v.29 no.6
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• pp.375-391
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• 2022

This paper examined the impact of the cross-sectional structure on the structural results under different loading conditions of reinforced concrete (RC) members' management limited in Carbon Fiber Reinforced Polymers (CFRP). The mechanical properties of CFRC was investigated, then, totally 32 samples were examined. Test parameters included the cross-sectional shape as square, rectangular and circular with two various aspect rates and loading statues. The loading involved concentrated loading, eccentric loading with a ratio of 0.46 to 0.6 and pure bending. The results of the test revealed that the CFRP increased ductility and load during concentrated processing. A cross sectional shape from 23 to 44 percent was increased in load capacity and from 250 to 350 percent increase in axial deformation in rectangular and circular sections respectively, affecting greatly the accomplishment of load capacity and ductility of the concentrated members. Two Artificial Intelligence Models as Extreme Learning Machine (ELM) and Particle Swarm Optimization (PSO) were used to estimating the tensile and flexural strength of specimen. On the basis of the performance from RMSE and RSQR, C-Shape CFRC was greater tensile and flexural strength than any other FRP composite design. Because of the mechanical anchorage into the matrix, C-shaped CFRCC was noted to have greater fiber-matrix interfacial adhesive strength. However, with the increase of the aspect ratio and fiber volume fraction, the compressive strength of CFRCC was reduced. This possibly was due to the fact that during the blending of each fiber, the volume of air input was increased. In addition, by adding silica fumed to composites, the tensile and flexural strength of CFRCC is greatly improved.