• Composites Research
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• v.24 no.3
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• pp.17-24
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• 2011

The EAM simulation of nanoindentation was performed to investigate misfit dislocation slip in the Ag/Cu. The film layer, whose thickness in the range of 2-5nm, was indented by a spherical indenter with the N$\'{o}$se-Hoover thermostat condition. The simulation shows that the indentation position relative to misfit dislocation (MFD) has the effect on the dislocation, glide up or cross slip, for Ag film layer thickness less than 4 nm. Elastic energy variation during MFDs slip was revealed to be a key factor for the softening of Ag/Cu. The critical film layer thickness was evaluated for each case of Ag/Cu according to the spline extrapolation technique.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.23 no.3
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• pp.247-254
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• 2010

Due to lightweight and high durability of glass-fiber reinforced polyester (GFRP) materials, they are promising alternatives to conventional construction materials such as steel, concrete and wood. As good application examples of GFRP materials, several types of temporary arch bridges were suggested and verified by finite element analyses in our previous study where snap-fit GFRP decks were applied. In this paper, we conduct a structural performance test to verify safety and serviceability of the temporary arch bridge, where snap-fit GFRP decks are assembled by bolts. The structural problems occurred in this test are also discussed and improvement of temporary arch bridges is suggested to resolve the occurred structural problems.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.21 no.3
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• pp.217-223
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• 2008

Glass-fiber reinforced polyester (GFRP) composite material is a promising alternative to existing construction materials such as steel, concrete and wood due to light weight and high durability of GFRP composite material. If a temporary arch bridge is built by GFRP composite deck, rapid construction of the bridge and reuse of the GFRP composite deck are possible. In this paper, we develop a type of temporary arch bridges that can be built by easy assembling of GFRP composite decks. For this purpose, several possible types of temporary arch bridges are suggested and verified by finite element analysis.

• Proceedings of the Korea Information Processing Society Conference
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• 2014.11a
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• pp.1155-1158
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• 2014

모바일 쇼핑의 급속한 성장으로 인해 스마트 쇼핑과 같은 쇼핑시장의 새로운 패러다임이 발생하였다. 본 연구에서는 모바일 쇼핑시장을 이루고 있는 주된 의류분야에서 오프라인과의 통합된 시스템을 개발하여 새로운 의류 IT의 출현을 도모하고, 이를 통해 고객 만족도와 서비스를 높일 수 있는 방안을 연구하였다. 오프라인 매장에 스캐너를 개발하여 오프라인 쇼핑의 활용도를 높이고 고객에게 브랜드의 새로운 차별성을 제시할 수 있는 방안을 모색하였다. 스캐너에 키넥트를 이용하여 인체 골격 구조에 따라 신체를 측정하고 신체 측정 시 발생하는 사용자 인식률 및 스캐너와의 거리에 따라 변하는 오차 범위를 연구하였다. 스캐너는 의류 매장 안에서 신체치수를 측정할 뿐 아니라 의류 RFID 태그를 이용하여 직접 입어보지 않고 가상 Fitting할 수 있는 기능을 가진다. 또한 측정된 치수를 스마트 폰과 블루투스로 연결하여 가상 아바타를 생성 할 수 있고 이는 또한 스마트폰에서 가상 Fitting이 가능하여 오프라인과 모바일 쇼핑의 통합성을 추구했다.

• Journal of IKEEE
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• v.24 no.4
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• pp.1069-1073
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• 2020

This paper presents the performance analysis of a long-range marine communication system developed for monitoring the fishing gears. LoRa based buoys were developed to monitor fishing gears. The buoy sends its coordinates along with other relevant information to the central monitoring station via a gateway. During the experiment, a up to 30 km of communication between a buoy and a gateway was successfully tested.

• Journal of the Korean Society of Clothing and Textiles
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• v.45 no.1
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• pp.123-135
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• 2021

This study provides basic information for the convenient size selection of T-shirts in an online purchasing environment. The best preferred T-shirts fit was selected among five sizes of T-shirts according to body size group. The subjects were 103 students majoring in clothing. After setting a virtual model with her own body sizes, the subjects chose the best preferred fit among five sizes of T-shirts that included the one suitable to their bust circumference, two smaller T-shirts and two larger T-shirts. As a result, they preferred the fit of larger size T-shirts than body size, but they preferred a different fit by the body characteristic group such as waist height group and hip circumference group. T-shirt length was affected by waist height; in addition, shoulder ease was affected by hip circumference and bust circumference. Therefore waist height and hip circumference should be considerable sizes when consumers choose T-shirts sizes with a preferred fit.

• Fashion & Textile Research Journal
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• v.17 no.4
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• pp.588-596
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• 2015

This study aims to provide the basic reference necessary in improving the fitness of a ready-to-wear brand jacket through a research on the wearing conditions and preferences regarding a tailored jacket by body shape of the women in their 30s. The following results were drawn by implementing the research method of the self-administered type survey targeting 201 women in their 30s from August 14~28, 2014. First, the female consumers in their 30s preferred one button slim fit jacket when purchasing a tailored jacket and chose a close-fitting size. Second, the slim fit tailored jacket consumers preferred a jacket with some extra portion in the bust and hip areas but tightly fit in the waist area. Third, when purchasing a jacket under the ready-to-wear size system, the women with a triangle shape similar to a standard body silhouette had less instances of mending a jacket while the women with a big or small rectangle shape different from a standard body silhouette had more experiences of mending a jacket. Accordingly, it is expected of the manufacturers to increase the fitness satisfaction of the consumers by identifying the problems concerning the fitness and suggesting the improvement plans to produce a jacket of a good fitness reflecting the properties of different body shapes through such research on the wearing conditions and preferences regarding a tailored jacket by body shape of the women in their 30s.

• Korean Journal of Materials Research
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• v.26 no.4
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• pp.173-181
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• 2016

In order to use coal tar pitch (CTP) as a raw material for carbon fibers, it should have suitable properties such as a narrow range of softening point, suitable viscosity and uniform optical properties. In this study, raw CTP was modified by heat treatment with three types of polymer additives (PS, PET, and PVC) to make a spinnable pitch for carbon fibers. The yield, softening point, C/H ratio, insoluble yield, and meso-phase content of various modified CTPs with polymer additives were analyzed by changing the type of polymer additive and the heat treatment temperature. The purpose of this study was to compare the properties of CTPs modified by polymer addition with those of a commercial CTP. After the pitch spinning, the obtained green fibers were stabilized and carbonized. The properties of the respective fibers were analyzed to compare their uniformity, diameter change, and mechanical properties. Among three polymer additives, PS220 and PET261 pitches were found to be spinnable, but the carbon fibers from PET261 showed mechanical properties comparable with those of a commercial CTP produced by an air-blowing method (OCI284). The CTPs modified with polymer additive had higher ${\beta}$-resin fractions than the CTP with only thermal treatment indicating a beneficial effect of carbon fiber application.

• Korean Journal of Materials Research
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• v.24 no.6
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• pp.293-300
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• 2014

Coal-tar pitch, a feedstock which can be heat-treated to create graphite, is composed of very complex molecules. Coal-tar pitch is a precursor of many useful carbon materials (e.g., graphite, carbon fibers, electrodes and matrices of carbon/carbon composites). Modified coal-tar pitch (MCTP) was prepared using two different heat-treatment methods and their properties were characterized and compared. One was prepared using heat treatment in nitrogen gas; the other was prepared under a pressure of 350 mmHg in air. The MCTPs were investigated to determine several properties, including softening point, C/H ratio, coke yield, formation of anisotropic mesophase and viscosity. The MCTPs were subject to considerable changes in chemical composition due to condensation and polymerization in the used-as-received coal-tar pitch after heat-treatment under different conditions. The MCTPs showed considerable increases in softening point, C/H ratio, and coke yield, compared to those of as-received coal-tar pitch. The MCTP formed by heat-treatment in nitrogen showed isotropic phases below $350^{\circ}C$ for 1 h of soaking time. However, MCTP heat-treated under high pressure (350 mmHg) showed isotropic phases below $300^{\circ}C$, and showed anisotropic phases above $350^{\circ}C$, for 1 h of soaking time. The viscosity of the MCTPs increased with increase in their softening points.

• Korean Journal of Human Ecology
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• v.12 no.4
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• pp.559-570
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• 2003

The focus of this research was concerned with studying lower body type for Korean adult males. To understand the features of men's lower body required to organize an optimal sizing system for men's tight-fit slacks, information from the measuring values based on research on the physical standard of the nation(l997) were summarized; in addition, a factor analysis and a cluster analysis among multivariate analyses were performed. In terms of the need for appropriate fit in motorcycle wear, basic lower body parts applying to each item had to be taken into consideration to enhance sizing suitability. In the case of the length of the lower limbs, the inclusion of protectors plays an important role in affecting sizing. The factors related to the lower body were defined as follows: Factor 1 was the vertical dimension of the lower body, Factor 2 was the horizontal dimension of waist and hip, Factor 3 was the horizontal dimension of the lower limbs, Factor 4 was the length of hips, and Factor 5 was the ankle height. The lower body part was also divided into 3 clusters. Cluster 1 referred to the smallest stature and skeleton structure among the 3 body types. Cluster 2 represented the biggest stature, with a thin lower limbs body type. Cluster 3 represented a medium stature but with a large skeleton structure of lower limbs, a muscular type. In conclusion, Cluster 2 appeared most in the 20s age groups, but Cluster 3 appeared most in each of the 30s, 40's, and 50's age groups.