• Journal of Fashion Business
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• v.13 no.1
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• pp.91-101
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• 2009

The purpose of this study is to develop semantic differential scales which are necessary to evaluate visual image and effect of flare skirt. As a result of the first survey of 362 female college students, the most effective factors for shape of flare skirt are silhouette, volume of flare, and skirt length. Based on this result, we made flare skirt simulation for visual evaluation with using I-Designer program. 4 kinds of volume of flare($90^{\circ},\;180^{\circ},\;270^{\circ},\;360^{\circ}$) and 3 kinds of skirt length(48cm, 58cm, 68cm) are combined as variables for flare skirt of visual evaluation. For the second survey of 362 female college students, we asked to write suggested adjectives freely. As a result, we could draw out 210 adjectives. 'Feminine' was most frequently used word for flare skirt, and then, 'vivid', 'rhythmic', 'cute', 'soft', 'fat', and 'comfortable' in this order. With considering frequently used words in the preceding study, we selected 41 adjectives. Antonyms were selected from the resulted frequency of this study and preceding study, and the rest of words were found from dictionary. From these process, we developed semantic differential scales for visual image and effect of flare skirt.

• Transactions of Materials Processing
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• v.29 no.1
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• pp.37-43
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• 2020

Increasing the critical current density of superconducting wire is one of the difficult challenges in the field of superconductivity. It is well known that the higher volume fraction of uniformly dispersed α-Ti is able to enhance the critical current density of superconducting material NbTi because α-Ti serves as a flux pinning center. The volume fraction of α-Ti highly depends on the grain size of NbTi because α-Ti precipitates at the grain boundaries or triple points. For this purpose, we investigated the effect of initial microstructures of NbTi obtained from hot rolling in various temperature conditions on the critical current density. In addition, subsequent heat treatment was assigned to precipitate α-Ti and groove rolling/cold drawing was adopted to produce a wire with a diameter of about 1.0 mm. It was observed that the band structure was formed after hot rolling at 500~600℃. It was also found that the volume fraction of α-Ti after hot rolling at 500~600℃ was higher and it led to the highest critical current density.

• Journal of Welding and Joining
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• v.30 no.2
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• pp.70-75
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• 2012

In this study, effect of nitrogen volume in the shielding gas of Ar-$N_2$ mixing gas on the bead shape, hardness and microstructure of GTA welds of 3mm thick Commercial Pure Ti was investigated. As the nitrogen volume increased, the welding current for full penetration was reduced and hardness in the fusion zone significantly increased compared with that of the base metal, but there is no difference in the hardness of HAZ. Microstructure in the fusion zone with pure Ar gas changed from equiaxed alpha of the base metal to serrated alpha. On the other hand, microstructure using Ar-$N_2$ mixing gas changed to acicular alpha. With the increasing of nitrogen content, the amount of acicular alpha increased and the size of that was fine.

• Journal of Ocean Engineering and Technology
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• v.5 no.2
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• pp.198-198
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• 1991

Not only difference of fatigue crack growth and propagation behavior resulted from the grain size, the hardness ratio and volume fraction in M.E.F. dual phase steel composed of martensite in hard phase and ferrite in soft phase, but also the effects of the plastic constraint were investigated by fracture mechanics and microstructural method. The main results obtained are as follows: 1) The fatigue endurance of M.E.F. steel increases with decreasing the grain size, increasing the ratio of hardness and volume fraction. 2) The initiation of slip and crack occures faster as the stress level goes higher. These phenomena result from the plastic constraint effect of the second phase. 3) The crack propagation rate in the constant stress level is faster as the grain size gets larger, the ratio of hardness lower and volume fraction smaller.

• Journal of Ocean Engineering and Technology
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• v.23 no.6
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• pp.87-92
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• 2009

The effect of aging on the precipitation of the $\sigma$ phase and the corrosion resistance in tungsten substituted super duplex stainless steels was investigated. The volume fraction of the $\sigma$ phase and the current density increased with aging at temperatures up to $750^{\circ}C$ and then decreased. With an increase in aging time, the volume fraction of the $\sigma$ phase and the current density also increased. The $\sigma$ phase hardly influenced the corrosion resistance. With the substitution of tungsten for molybdenum in super duplex stainless steel, the volume fraction of the $\sigma$ phase and the current density decreased remarkably.

• The Journal of Korean Medicine
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• v.21 no.4
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• pp.9-15
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• 2000

Objective : The aim of this study was to investigate the neuroprotection effect of estrogen on brain atrophy following cerebral infarction. Method : All animals in this study were classified into 4 groups; ovariectomy group (OVXgroup), cerebral infarction group (INF group), combination ovariectomy and cerebral infarction group (OVX + INF group), and naturally intact group for control data (NOR group). Cerebral infarction was made by Chen's method with some modification. Ovariectomy was performed by Wayforth's method. Experimental data for each group was collected at 15 days, month, 3 months, and 6 months after starting observation. Serum $17{\beta}-estradiol(E2)$ was determined by radioimmunoassay. Brain volume was measured and calculated with image analysis. Each brain was sliced at intervals of 2mm in chamber after 30 min of freezing in refregerater. Cerebral volume was obtained by sum of volume of each slice level, which was mean $area{\;}{\times}{\;}2mm$. Results : Cerebral ischemia was found to decrease the serum concentration of $17{\beta}-{\;}estradiol(E2)$ and to inhibit the physiologically conpensatary function of the ovariectomized rats. Also we found that deprivation of estrogen have resulted in more severe cerebral atrophy followed by cerebral infarction. Conclusion : It is suggested that estrogen has a neuroprotection effect on cerebral atrophy following cerebral infarction.

• Journal of the Korean Society for Advanced Composite Structures
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• v.4 no.4
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• pp.15-21
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• 2013

This study carried out finite element deflection analysis of cylindrical shell structures made of composite materials, which is based on the micro-mechanical approach for different fiber-volume fractions. The finite element (FE) models for composite structures using multi-scale approaches described in this paper is attractive not only because it shows excellent accuracy in analysis but also it shows the effect of the material combination. New results reported in this paper are focused on the significant effects of the fiber-volume fraction for various parameters, such as fiber angles, layup sequences, and length-thickness ratios. It may be concluded from this study that the combination effect of fiber and matrix, largely governing the dynamic characteristics of composite shell structures, should not be neglected and thus the optimal combination could be used to design such civil structures for better dynamic performance.

• Advances in concrete construction
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• v.10 no.4
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• pp.319-332
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• 2020

The impacts of reinforcing concrete matrix with steel fibers, polypropylene fibers and recycled plastic fibers using different volume fractions of 0.15%, 0.5%, 1.5% and 2.5% on the compressive and tensile characteristics are experimentally investigated in the current research. Also, flexural behavior of plain concrete (PC) beams, shear performance of reinforced concrete (RC) beams and compressive characteristics of both PC and RC columns reinforced with recycled plastic fibers were studied. The experimental results showed that the steel fibers improved the splitting tensile strength of concrete higher than both the polypropylene fibers and recycled plastic fibers. The end-hooked steel fibers had a positive effect on the compressive strength of concrete while, the polypropylene fibers, the recycled plastic fibers and the rounded steel fibers had a negative impact. Compressive strength of end-hooked steel fiber specimen with volume fraction of 2.5% exhibited the highest value among all tested samples of 32.48 MPa, 21.83% higher than the control specimen. The ultimate load, stiffness, ductility and failure patterns of PC and RC beams in addition to PC and RC columns strengthened with recycled plastic fibers enhanced remarkably compared to non-strengthened elements. The maximum ultimate load and stiffness of RC column reinforced with recycled plastic fibers with 1.5% volume fraction improved by 21 and 15%, respectively compared to non-reinforced RC column.

• Journal of Microbiology and Biotechnology
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• v.12 no.1
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• pp.149-152
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• 2002

The effect of pressure on the catalytic properties of glutamate racemase from Aquifex pyrophilus, an extremophilic bacterium, was investigated. The activation volume for the overall reaction $({\Delta}V^{\neq})$ and catalysis $({{Delta}V_{cat}}^{\neq})$ was -96.97 ml/mol and 4.97 ml/mol, respectively, while the reaction volume for the substrate binding (${\Delta}V_{K_m^-1}$) was -101.94 ml/mol. The large negative ${\Delta}V^{\neq}$ for the overall reaction indicated that the pressurization of glutamate racemase resulted in enhanced catalytic efficiencies. In addition, this value was also due to the large negative ${Delta}V_{K_m^-1}$ for the substrate binding. The negative value of ${Delta}V_{K_m^-1}$ implied that the conformational changes in the enzyme molecule occurred during the substrate binding process, thereby increasing the degree of hydration. The small value of ${{Delta}V_{cat}}^{\neq}$suggested that the pressure did not affect the glutamate racemase catalysis after the substrate binding.

• Transactions of Materials Processing
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• v.27 no.2
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• pp.93-99
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• 2018

An analytical solution for the tensile ductility in porous ductile materials was derived based on an Irwin's approach of the elastic-plastic deformation in fracture mechanics. This was in good agreement with the experimental results of a tensile ductility in a sintered pure Al, and could solve the discrepancies in the Brown and Embury, or the McClintock models. This model was also offered as an advanced analytical solution considering the effect of stress triaxiality of pore tip in addition to pore interactions, material properties of matrix, and local deformation effect around pore. The evaluation of an analytical solution in the sintered pure Al powder compacts showed that the tensile ductility depends not only on the volume fraction of pores, but also on the pore size and on the mechanical properties of the matrix. The tensile ductility of the sintered pure Al compacts decreased rapidly with the increasing of a pore volume fraction, despite of the excellent tensile ductility of the matrix. This significant decrease in the tensile ductility was mainly attributed to the low yield strength of the matrix and small pore size. Particularly, the effects of the large radius and high volume fraction of the pore on the tensile ductility in Al-Form, were thus reasonably predicted by this analytical equation.