• Proceedings of the Korean Magnestics Society Conference
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• 2007.05a
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• pp.182.2-182.2
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• 2007

• Proceedings of the Materials Research Society of Korea Conference
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• 1999.11a
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• pp.153-153
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• 1999

• Transactions of the Korean Society of Mechanical Engineers A
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• v.37 no.6
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• pp.775-782
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• 2013

In this study, as a series of studies aimed at investigating the spatial randomness of fatigue crack growth for friction stir welded (FSWed) 7075-T651 aluminum alloy joints, the fatigue crack growth behavior of FSWed 7075-T651 aluminum alloy joints was investigated for LT orientation specimens. Fatigue crack growth tests were conducted under constant stress intensity factor range (SIFR) control for 5 specimens of the FSWed 7075-T651 aluminum alloy, including base metal (BM), heat affected zone (HAZ), and weld metal (WM) specimens. The mean fatigue crack growth rate of WM specimens was found to be the highest, whereas that of HAZ and WM specimens was the lowest. Furthermore, the variability of fatigue crack growth rate was found to be the highest in WM specimens and lowest in BM specimens.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.26 no.5
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• pp.960-968
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• 2002

In this research, the effects of fiber stacking sequence on damage behaviors of FML(Fiber Metal Laminates) subject to indentation loading. SOP (Singly Oriented Ply) FML and angle ply FML were fabricated to study fiber orientation effects and angle ply effects. FML were fabricated by using 1050 aluminum laminate and carbon/epoxy prepreg. To increase adhesive bonding strength, Al laminate was etched using FPL methods. The static indentation test were conducted by using UTM under the 2side clamped conditions. During the tests, load and displacement curve and crack initiation and propagation behaviors were investigated. As fiber orientation angle increases, the crack initiation load of SOP FML increases because the stiffness induced by fiber orientation is increased. The penetration load of SOP FML is influenced by the deformation tendency and boundary conditions. However, the macro-crack of angle ply FML was initiated by fiber breakage of lower ply because angle plies in Angle ply FML prevents the crack growth and consolidation. The Angle ply FML has a critical cross-angle which prevent crack growth and consolidation. Damage behavior of Angle ply FML is changed around the critical cross-angle.

• Journal of the Korea Convergence Society
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• v.11 no.4
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• pp.287-294
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• 2020

The purpose of this study was to analyze the influence of the achievement goal orientation of military cadets and grit on the military cadets' certification of physical fitness rank and on the improvement of the grade. To accomplish the research purpose, a survey was conducted to 350 cadets of the Korea Military Academy in December 2019, and 322 valid responses were analyzed by applying the path analyses. As a result, among the sub-factors of achievement goal orientation, the direct effect of task goal orientation on the two sub-factors of the grit was statistically significant. In addition, the effect of task goal orientation on grade physical certification was statistically significant, with the use of grit(maintaining interest) and grit(continuing effort) as meditating variables. In addition, task goal orientation had a significant effect on the improvement of physical strength grade via two sub-factors of Grit as meditating variables.

• Horticultural Science & Technology
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• v.35 no.4
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• pp.402-409
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• 2017

We performed seed germination tests to investigate the effects of seed sowing orientation on germination viability on peanut (Arachis hypogaea L.) sprouts. Specifically, we assessed the influence of seed sowing orientation on germination rate, seedling weight, and seedling length, as well as the seedling vigor index. The seeds were sown in oak tree sawdust at 3.0 cm depth. Four seed orientations were tested: vertical with the hypocotyl end down, vertical with the hypocotyl end up, horizontal with the hypocotyl end down, and horizontal with the hypocotyl end up. The mean seed germination percentages of the four seed orientations were significantly different (p < 0.01) and ranged from 25 to 91.7%. The vertical orientation with hypocotyl-end-down and hypocotyl-end-up orientations showed the highest (91.7%) and lowest (25%) germination rates, respectively. The vertical orientation with the hypocotyl end down produced the heaviest (4.9 g) seedlings and the longest hypocotyls (4.65 cm). This orientation also produced the longest true leaf + epycotyl (2.15 cm) and had the highest seedling vigor index (197.1). The seedlings had a straight growth pattern, whereas seedlings from seeds sown with the hypocotyl up had an awkward plumular hook shape. Taken together, to produce peanut sprouts, we recommend placing the seeds vertically with the hypocotyl end down because this orientation leads to a high germination rate, high biomass production, and high overall seedling quality.

• Fashion & Textile Research Journal
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• v.17 no.6
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• pp.932-941
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• 2015

An aging population and increasing consumer demand for high-quality and innovative new products are key drivers for growth in the cosmeceutical industry. Cosmeceuticals are defined as products with biologically active ingredients that have a measurable effect on the user. This study explored the effects of shopping orientation and store attributes on impulse buying behavior for cosmeceuticals. We obtained 437 usable questionnaires from university students who had purchased cosmeceutical products. Data analysis was conducted using confirmatory factor analysis and structural equation modeling analysis via AMOS 18.0. The findings were: 1) hedonic shopping orientation and convenience shopping orientation had positive effects on product efficacy and promotion of the cosmeceutical store 2) brand shopping orientation had a positive effects on store atmospheric, skin care service, and brand of the cosmeceuticals store and 3) product efficacy and promotion of store attributes had a direct effect on impulse buying behavior for cosmeceuticals. Consumers who tended to enjoy the shopping to refresh themselves and to experience convenient shopping were likely to purchase cosmeceuticals impulsively, which mediated by the store attributes (product efficacy and promotion). Therefore, we confirmed partly causal relationships among the shopping orientation, store attributes, and impulse buying behavior of cosmeceuticals. Both managerial and theoretical implication for practitioners and researchers were discussed for managing product information more efficiently along with promotion strategies to trigger cosmeceuticals consumers in the context of shopping.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.6 no.3
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• pp.293-300
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• 1996

A continuous growth method (Orr's method) were developed to grow LiNbO3 single crystals. The optimum growth condition established are as follows; When the controlled temperature of a platinum crucible were 1190℃∼1210℃, the pulling rate was 2 mm/hr, the feeding rate was 1.5∼2.5 g/hr, and the rotation speed was 20 rpm. The phase and growth orientation of the grown LiNbO3 crystals wer characterized by a X-ray diffraction method. The overflowing phenomena, which induced cracking into the grown crystal during the process, was effectively suppressed by the control of the growth parameter.

• Journal of the Korean Society for Heat Treatment
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• v.27 no.2
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• pp.79-89
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• 2014

The effect of carbon on the microstructure and texture of low carbon steels was investigated in a series of 1.6 Mn-0.3Cr-0.2Mo-0.001B steels with carbon ranging from 0.021 to 0.048%. Intensity of {111} orientation increased with decreasing the carbon content, resulting in the increase in $r_m$ value. The highest $r_m$ value of 1.30 was obtained in 0.021%C steel annealed at $820{\sim}850^{\circ}C$ according to the typical galvannealing heat cycle. Martensite volume fraction was not substantially affected by the annealing temperature. It was found that the fine and uniformly distributed martensite particles which were present in amounts of about 5% volume fraction were desirable for the highest $r_m$ value. The other factor affecting the high $r_m$ value was the preferred epitaxial growth of retained ferrite with {111} orientation into austenite during cooling.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2004.10a
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• pp.479-482
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• 2004

The behavior of fatigue delamination in a GLARE(Glass Fiber Reinforced Metal Laminates) under fatigue loading conditions investigated. The behavior of fatigue delamination was examined basing on investigation of the crack and delamination using a SAM (Scanning Acoustic Microscope). The crack and delamination behavior on the relationship among a-N, SAM images and crack length-delamination length were considered. The test results indicated the features of different fatigue delamination and crack growth according to each fiber orientation angle and also obtained to more increase delamination than crack through the relationship between crack length and delamination length in GLARE.