• Science of Emotion and Sensibility
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• v.15 no.1
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• pp.141-148
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• 2012

This study investigated the structural coloration and fabric hand of the caustic reduced fabrics for emotional garment using structural color yarns, which was spun by 37 alternating nylon and polyester layers capable of producing basic colors using biomimetic technology. The colorations of the three kinds of structural color yarns were confirmed using multi angle spectro-photometer, and their triangular cross sections composed with 37 alternating nylon and polyester layers were measured using SEM and were discussed with layer length in relation with coloration and spinning conditions were also set up. The apparent color difference and reflectance of the three kinds of fabrics with different density and weave pattern were analysed as ranging from 400nm to 700nm. The optimum fabric structural design which is made by warp and weft densities(194ends/in ${\times}$ 105picks/in) and caustic reduction condition by $100^{\circ}C$ temperature and 60minutes with NaOH, 20g/l solution were decided through analysis of the mechanical properties and fabric hands of these three kinds of fabrics treated with 3 kinds of the caustic reduction conditions. And it was shown that the rate of caustic reduction was increased from 13% to 23% with increasing temperature and time of caustic reduction. The extensibility, bending rigidity and shear modulus of caustic reduction treated fabrics were decreased by treatment of caustic reduction, on the other hand fabric compressibility was increased. And it was shown that the hand value of specimen number one which was treated with temperature $100^{\circ}C$ and time 60minute was the best and the hand of this fabric was better than that of Morpho $fabric^{(R)}$ made by Teijin co. Japan.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.32 no.1
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• pp.1-5
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• 2019

In this paper, the experimental study and finite elements analysis were conducted on homogeneous and dissimilar metals single lap-shear bonded joints to investigate the factor that affect the joint failure load. It was found that factors which have the significant effects on the failure load of the joint was stiffness of the adherends. And from experimental results, it can be confirmed that the failure load increases linearly with overlap length increases. And the failure load of dissimilar metal joints is approximately 1KN(10~17%) larger than homogeneous metal joints. In order to confirm this phenomenon, the stress distribution and strain distribution of the specimens were analyzed through the finite element analysis. The difference between homogeneous metals joints and dissimilar metals joints is that stress and strain in adhesive are concentrated at the end of the overlap zone close to aluminium which has lower rigidity than aluminium in case of dissimilar metals joints. From high rigidity of steel, the stress concentration in bonds are decreased and it cause increase of the failure strength at dissimilar metal joints.

• Journal of Korean Ophthalmic Optics Society
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• v.1 no.2
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• pp.49-55
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• 1996

Hydrogenated amorphous carbon(a-C:H) films were fabricated by the low-frequency (60Hz) glow discharge of the mixture of methane and hydrogen, and their electrical properties were investigated. We observed that a-C:H films show the persistent photoconductivity(PPC) by illumination of heat-filtered while light for a few seconds. The PPC was about 10 times larger than the annealed dark conductivity. The samples clearly showed metastable characteristics. With increasing illumination times from 1 to 100 min, the annealing activation energy of the PPC was about 0.39eV. The annealing temperature at which the PPC disappeared increasing from $100^{\circ}C$ to $130^{\circ}C$. Illumination longer than 80 min leads to the formation of ${\pi}$ defects and to the decrease of PPC. From these results, we tentatively propose that the states in the ${\pi}$ band act as deep trap centers generating the metastabilities.

• The Korean Journal of Food And Nutrition
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• v.19 no.1
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• pp.22-27
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• 2006

This study was carried out to determine the optimum conditions for making soybean curd(or tofu) from defatted soybean flour.. Heating soymilk above $80^{\circ}C$ for at least $5{\sim}10\;min$ was necessary for soybean protein to form aggregates during subsequent coagulation process with glucono-${\delta}$-lactone(GDL). For maximum yield of tofu, with water content of approximately 80%, extra addition of 20 g of oil and 5 g of GDL per 425 g of soybean flour was needed. Maintaining soymilk temperature around $75^{\circ}C$ for 5 min was necessary when GDL was used as the coagulant.

• Nuclear Engineering and Technology
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• v.27 no.3
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• pp.327-335
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• 1995

The normal shutdown and maintenance period of a nuclear power plant can be remarkably shortened when the examination and maintenance works in steam generator tubes are simultaneously carried out with refueling job. There are nozzle dams to Hock the coolant How from reactor to steam generator. Workers are reluctant to install nozzle dam because of the high radiation exposure and the limited working space in steam generator. Moreover, the heavy weight of present nozzle dam makes it installation and removal works much difficult. In this paper, a lighter KAERI nozzle dam with increased flexural rigidity-to-weight was designed and manufactured by changing the structure design of the present nozzle dam and by selecting new material, carbon fiber-reinforced plastic.

• Journal of the Korea institute for structural maintenance and inspection
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• v.11 no.3
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• pp.77-86
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• 2007

The more demands on efficient utilization of resources, the more structural engineers prefer to select remodeling to improve old building's capacity. A series of four shear wall specimens were tested under constant axial stress and reversed cyclic lateral loading in order to evaluate the effect of the opening on the lower center of the wall induce by remodeling. Consequently, the existence of opening was verified to induce a different failure, which was caused by reduction of compression strut area formed on the wall to diagonal direction. Especially, the ultimate strength of the wall with an opening was revealed approximately 35% lower than that of the wall without an opening. And the similar results were appeared in characteristics of stiffness and energy dissipation capacity.

• International Journal of Highway Engineering
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• v.6 no.4 s.22
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• pp.91-100
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• 2004

This study was Performed to evaluate applicability of color flexible pavement concrete (CFPC) for motorway pavement. Color flexible pavement has been applied to non-motorway pavements, such as pedestrian and bicycle road. Two polymers were used to modify the binder and to strengthen the stiffness of pavement mixture. Waste paper was used to prevent the asphalt of gap-grade mixture from draining. Marshall properties, indirect tensile strength(ITS), tensile strength ratio(TSR) before and after freezing-and-thawing treatment and artificial aging, permanent deformation and fatigue life were measured. Color bituminous concrete mixtures used this study had nearly the same quality in mechanical properties when compared with conventional asphalt concrete mixtures manufactured with AP-3 and all mixtures satisfied with domestic specification for motorway pavement. Therefore, it is proved that the color bituminous concrete used this study can be applied for motorway pavement.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2002.11a
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• pp.89-93
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• 2002

One of the primary factors like plate structure in ship is redundancy structure that is comparable with ocean structure and frame structure. The more component material becomes buckling collapsed locally the less structure stiffness becomes accordingly. As a result, by increasing the load distribution of my other subsidiary structure continually component member collapses, therefore the structure could be in danger of collapse. So, in order to interpret this phenomenon precisely, the study on boundary condition of the ship's plate and post-buckling analysis must be considered In this study, the rectangular plate is compressed by the in-plane load Buckling & Ultimate strength characteristics are applied o be the elasto-plasticity large deformation by ansys code with F.E.M method On this basis, elasto-plasticity of the plain plate are investigated. This study proved elasto-plasticity behaviour of the ship's plate in accordance with boundary condition based on the series analysis in case of the compressive load operation

• Journal of Korean Society of Steel Construction
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• v.15 no.5 s.66
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• pp.499-507
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• 2003

As the load is increased on the steel-concrete composite structure, its interface begins to show nonlinear behavior due to the reduction of interaction, micro-crack, slip and separation, and it causes slip-softening, Therefore, it is essential to consider the partial-interaction analysis technique. Until now, however, full-interaction or, in some instances, the linear-elastic model, which are insufficient to simulate accurate behavior, are assumed in the analysis of composite structure since the analysis method and nonlinear model for interface are very difficult and complicated. Therefore, the design of composite structure is followed by the experimental method which is inefficient-because a number of tests have to be carried out according to the design environments. In this study, we carried out the nonlinear analysis according to various interface nonlinear models by interaction magnitude, and analyzed more accurate structural behavior and performance by maximum tangential traction and slip-softening at the interface. As a result of this study. we were able to prove that the nonlinear model of interface more exactly represents behavior after yielding, such as ultimate load: that initial tangential stiffness of interface has a significant effect on the yielding load of structural members or part: and that the maximum tangential traction and slip-softening mainly effects structural yielding and ultimate load. Therefore, the structural performance of composite structure is highly dependent on the steel-concrete interface or interaction, which may result in initial tangential stiffness, maximum tangential traction and slip-softening in nonlinear model.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.30 no.4
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• pp.275-282
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• 2017

In this paper, using a pattern transformation triggered by deformation, we propose a porous structure that exhibits the characteristic of negative Poisson's ratio in both tension and compression. Due to the lack of torque for rotational motion of ligaments, the existing porous structure of circular holes shows positive Poisson's ratio under tension loading. Also, the porous structure of elliptic holes has a drawback of low durability due to stress concentration. Thus, we design curved ligaments to increase the rotational torque under tension and to alleviate the stress concentration such that strain energy is uniformly distributed in the whole structure. The developed structure possesses better stiffness and durability than the existing structures. It also exhibits the negative Poisson ratio in both compression and tension of 10% nominal strain. Through nonlinear finite element analysis, the performance of developed structure is compared with the existing structure of elliptic holes. The developed structure turns out to be significantly improved in terms of stiffness and durability.