• KSCE Journal of Civil and Environmental Engineering Research
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• v.14 no.2
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• pp.257-268
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• 1994

An experimental study was carried out to elicit important factors causing cracks and rupture of steel members and their elements under imposed large repeated deformations, and of the quantitative relationships among the important physical factors leading to failure. Each of twenty-eight angles and nine thin-plates served as the specimen and was subjected to repeated axial load after undergoing inelastic buckling. Particular attention was paid to the effects of loading pattern, failure mode and cross-sectional shape on the very-low-cycle failure behavior under loading repetitions of the order of a few to twenty. The experimental results show that energy dissipation capacity depends heavily on the entire history of loading, the failure mode, the slenderness ratio and the width-to-thickness ratio. No simple quantitative relations were observed between the initiation of the visible cracks or rupture and the energy dissipation capacity. The maximum values of residual "net" strains are found to range from 25% to 40%, independent of the test parameters.

• Proceedings of the Korean Vacuum Society Conference
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• 2012.08a
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• pp.393-393
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• 2012

Optically active nanostructures such as subwavelength moth-eye antireflective structures or surface enhanced Raman spectroscopy (SERS) active structures have been demonstrated to provide the effective suppression of unwanted reflections as in subwavelength structure (SWS) or effective enhancement of selective signals as in SERS. While various nanopatterning techniques such as photolithography, electron-beam lithography, wafer level nanoimprinting lithography, and interference lithography can be employed to fabricate these nanostructures, roll-to-roll (R2R) nanoimprinting is gaining interests due to its low cost, continuous, and scalable process. R2R nanoimprinting requires a master to produce a stamp that can be wrapped around a quartz roller for repeated nanoimprinting process. Among many possibilities, two different types of mask can be employed to fabricate optically active nanostructures. One is self-assembled Au nanoparticles on Si substrate by depositing Au film with sputtering followed by annealing process. The other is monolayer silica particles dissolved in ethanol spread on the wafer by spin-coating method. The process is optimized by considering the density of Au and silica nano particles, depth and shape of the patterns. The depth of the pattern can be controlled with dry etch process using reactive ion etching (RIE) with the mixture of SF6 and CHF3. The resultant nanostructures are characterized for their reflectance using UV-Vis-NIR spectrophotometer (Agilent technology, Cary 5000) and for surface morphology using scanning electron microscope (SEM, JEOL JSM-7100F). Once optimized, these optically active nanostructures can be used to replicate with roll-to-roll process or soft lithography for various applications including displays, solar cells, and biosensors.

• Fire Science and Engineering
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• v.33 no.6
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• pp.114-119
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• 2019

We found metallic migration phenomena at the fire scene in Printed circuit board (PCB) of LED light equipment which are commonly used. Accordingly we did this study. In order to generate rapidly metallic migration, we experiment the water drop test under low voltage (3.0 V) and a small amount of water condition. As a results of our experiment, we saw the growth of metallic migration of Copper and checked directly short of the PCB between isolated two poles by Cu migration. Finally we saw the shape of dendrite pattern by Cu migration using Scanning electron microscope (SEM) and analyzed that components via Energy dispersive Spectrometer (EDS).

• The korean journal of orthodontics
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• v.22 no.3 s.38
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• pp.647-656
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• 1992

The purpose of this study was to evaluate the elastic memory process in cold worked stainless steel wire and the effect of heat treatment on it. 0.018 inch round and $0.019\times0.025$ inch rectangular wire (ORMCO stainless wire) were used in this study. Each wire type had 4 groups: non-heat treatment group, furnace heat treatment group, electric current heat treatment group, and bending after heat treatment group. Each group was consisted of 10 specimens. With the Jig, each wire was bent into v-shape uniformly, and width of two free ends of each v-shaped wire was measured by caliper (to the point of 0.1 mm correctly) at time interval of offjig, after heat treatment, 1, 2, 3, 4 hours, 1, 2, 3, 4, 5, 6 days, 1, 2, 3, 4 weeks after. The results were as follows: 1. In non-heat treatment group and bending after heat treatment group, elastic memory process was occured $60\%$ within 1 hour, and more than $90\%$ within 1 week. 2. In furnace and electric current heat treatment group, almost all elastic memory process was occured during teat treatment, and then specimen was stabilized dimensionally. 3. Magnitude of deformation by elastic memory was greater in heat treatment group than non heat treatment group and bending after heat treatment group. 4. There was no remarkable difference in deformation pattern between 0.018 inch round wire and $0.019\times0.025$ inch rectangular wire.

• Korean Journal of Plant Resources
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• v.29 no.4
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• pp.376-384
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• 2016

A comparative petal micromorphology of 15 taxa of tribe Sorbarieae was carried out using scanning electron microscopy (SEM) in order to evaluate their taxonomic and systematic implication. The characteristics of both adaxial and abaxial side of petal epidermal cells such as shape, arrangement, anticlinal wall and cuticular sculpture were described in detail. The Sorbarieae petal epidermal cells were identified as papillate or conical papillate (PCS) and rectangular-rugose tabular (TRS). Three types of petal micromorphology were found within the tribe based on the cell patterns of adaxial and abaxial side. Type I. PCS-TRS, Type II. PCS-PCS, Type III. TRS-TRS (adaxial-abaxial side). The petal epidermal cell types, anticlinal cell wall, and cuticular sculpture represent not only taxonomical importance for identification between or within the genera but also systematic implication. Moreover, this study provides a relation between petal epidermal cell pattern and insect pollinator (entomophily; melittophily) as an additional case.

• Korean Journal of Agricultural Science
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• v.41 no.4
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• pp.351-359
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• 2014

For identifying the plasmid DNA coding cry gene of Bacillus thuringiensis subsp. aizawai KB098 with high insecticidal activity against Spodoptera exigua, mutant isolates with no crystal protein were produced by $42^{\circ}C$ incubation condition and then mutant plasmid DNA band patterns were compared with those of KB098. KB098 isolates had 4 cry genes, cry1Aa, cry1Ab, cry1C, cry1D, and also had been found seven plasmid DNA. Though the SDS-PAGE experiment, it was confirmed that mutant didn't produce 130~145kDa protein band involved in bipyramidal shape crystal. Also, five mutant isolates had no cry genes coding plasmid DNA in PCR. In result of comparison the plasmid DNA of KB098 and 5 mutant isolates, only 1 plasmid DNA band was left out in mutant plasmid DNA pattern, so that the missing band was extracted from the gel. The missing(disappeared) plasmid DNA was the largest molecular size among the 7 plasmid DNA of KB098 and it was also confirmed this plasmid DNA had all 4 cry genes through PCR.

• Journal of the Korea institute for structural maintenance and inspection
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• v.19 no.2
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• pp.1-9
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• 2015

In this paper, the RC column-based joint connection part carry out loading test by reinforced hollow or extended Base Plate in order to confirm that RC joint punching shear reinforcement effect of applying the Base Plate. Base Plate thickness, extension length, size, and type as the variable, Base Plate suitable for the stress distribution and shape and dimensions confirmed through experiment and then reinforcing effect was analyzed. Experimentally, vertical load transmitted to the Base Plate from column to foundation is effective to stress distribution and then, type of hollow reinforcement more efficient than a closed. Through experiment, improve performance and ductility due to reinforcement and relative to the thickness of the existing foundation reduced even showed better performance than the existing. The behavior of the reinforced specimens be able to induce from brittle to ductile. Experiment on loading to destroy performed the pattern of cracks, destruction aspect before and after reinforcement.

• Journal of the Korea Fashion and Costume Design Association
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• v.17 no.1
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• pp.167-182
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• 2015

This study was to investigate the preference tendency by detail and material preference of summer one-piece dresses for the children, and evaluation standard of children's wear in purchasing one-piece dresses as an object of mothers who have girls as buying representatives of children's wear in order to supply real information of design about the one-piece dresses for the girls in accordance with the consumers' demands. The results of this study revealed that the one-piece dress was favorite one to them in purchasing their summer wear. This study showed tendency that the more the mother's fashion interest was, the more the mother's preference on the one-piece dress was. As to the material preference of one-piece dress, it preferred the natural fiber to the synthetic fiber much, and the preferred customer order in purchasing one-piece dresses for their children was analyzed as activity, material, design collar, and pattern. As to the preference by form factor of one-piece dress, it preferred A-line silhouette in the silhouette, natural waist in the waist position, 5~7cm from the knee in the length of one-piece dress, and flared skirt in shape of skirt. The preference on the collar type was soutien collar, and the preference on the neckline type was round neckline. In addition, the preference on sleeve form was shirtsleeve, and the preference on trimming was lace trimming.

• Journal of the Korea Fashion and Costume Design Association
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• v.17 no.1
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• pp.39-52
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• 2015

This study aims to analyze the characteristics of the male products for urinary incontinence by examining the types and characteristics of those registered in KIPO (Korean Industrial Property Office). Additionally, the types and characteristics, especially for the cloth products and the pads, of male panties for urinary incontinence on the market are analyzed. Men in their 60s with minor symptoms were selected as the subjects to evaluate the wearability. The results are as follows. 11 male products for urinary incontinence, registered in KIPO, are structurally different from those for women by having a separate pocket mainly for absorption. There are one disposable type and 7 cloth types, and the cloth panties can be classified as either united or separable type depending on the detachability of pads from the panties. The types of the panties vary according to the position, shape, and size of the attached pads on normal male panties (boxer, briefs, drawers). The fabrics for the urinary incontinence are usually piled in 3 to 5 layers by having the most absorptive layer on the top, the next with deodorizing characteristics, and the bottom with the waterproof fabric as basics with some additional layers of antibiotic or breathable fabrics. From the wearability test, it has been determined that the panties are not distinguishable in external appearance and the fitness is also not a problem since the size varies as the normal panties. It has been evaluated that the fitness of the panties is an important factor since the pad should be worn in any form; the pad sewed in the middle of the panties was evaluated to be more wearable than having a long pad. In case of separable panties, when the pattern and fabric is similar to the functional panties and the options such as the thickness of the pads or detachability are given to the users, it tends to be more satisfactory.

• Korean Journal of Plant Taxonomy
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• v.34 no.1
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• pp.27-35
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• 2004

Three unrecorded fern species from the flora of Korea belonging to family Dryopteridaceae, Ctenitis maximowicziana, Dryopteris lunanensis, and D. dcipiens var. diplazioides, are found along the valley of Mt. Wolgak (alt. 275m) in Gwangju, Korea. C. maximawicziana is well distinguished from the rest of the species in the genus including C. sinii by the color and morphology of scales in basal part of petioles, shape of blades, and the presence of round-reniform shaped indusia. Dryopteris lunanensis is also well distinguished from its close relative, D. atrata, by the number of lateral pinnae, degree of division of first and/or second pinnules in lower pinnae of the blades, and distribution pattern of sori. Dryapteris decipiens var. diplazioides is distinguishable from type variety by degree of division in lower pinnae of the blades. In terms of morphology, var. diplazioides seems to be intermediate between a type variety and D. fuscipes.