• Bulletin of the Korean Mathematical Society
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• v.51 no.5
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• pp.1299-1324
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• 2014

We prove the existence of uniform attractors $\mathcal{A}_{\varepsilon}$ in the space $H^1(\mathbb{R}^N){\cap}L^p(\mathbb{R}^N)$ for the following non-autonomous nonclassical diffusion equations on $\mathbb{R}^N$, $$u_t-{\varepsilon}{\Delta}u_t-{\Delta}u+f(x,u)+{\lambda}u=g(x,t),\;{\varepsilon}{\in}(0,1]$$. The upper semicontinuity of the uniform attractors $\{\mathcal{A}_{\varepsilon}\}_{{\varepsilon}{\in}[0,1]}$ at ${\varepsilon}=0$ is also studied.

• Wind and Structures
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• v.35 no.2
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• pp.83-92
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• 2022

When the rolling stocks run on the curve, the external rail has to be lifted to a certain level to balance the centrifugal force acting on the train body. Under such a situation, passengers may feel uncomfortable, and the slanted vehicle has the potential overturning risks at high speed. This paper conducted a wind tunnel test in an annular wind tunnel with φ=3.2 m based on a 1/20^th scaled high-speed train (HST) model. The sensitivity of Reynolds effects ranging from Re = 0.37×10⁶ to Re = 1.45×106 was tested based on the incoming wind from U=30 m/s to U=113 m/s. The wind speed covers the range from incompressible to compressible. The impact of roll angle ranging from γ=0° to γ=4° on train aerodynamics was tested. In addition, the boundary layer development was also analyzed under different wind speeds. The results indicate that drag and lift aerodynamic coefficients gradually stabilized and converged over U=70 m/s, which could be regeared as the self-similarity region. Similarly, the thickness of the boundary layer on the floor gradually decreased with the wind speed increase, and little changed over U=80 m/s. The rolling moment of the head and tail cars increased with the roll angle from γ=0° to γ=4°. However, the potential overturning risks of the head car are higher than the tail car with the increase of the roll angle. This study is significant in providing a reference for the overturning assessment of HST.

• Nuclear Engineering and Technology
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• v.51 no.4
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• pp.1081-1090
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• 2019

Detailed pulse shape analysis of a Geiger-$M{\ddot{u}}ller$ counter is performed to understand the pulse shape dependence on operating voltage. New data is presented to demonstrate that not all pulses generated in a GM counter are identical. In fact, there is a strong correlation between the operating voltage and the pulse shape. Similar to detector deadtime, pulse shapes fall in three distinct regions. For low voltage region, where deadtime was reported to reduce with increasing voltage, pulse generated in this region was observed to have a fixed pulse width with a variable tail. The pulse width and fall time of the tail was observed to be a function of applied voltage; exponentially reducing with increasing voltage with an exponent of negative 6E-04 and 2E-03 respectively. The second region showed a pulse without any significant tail. During this time the detector deadtime was earlier reported to be at its minimum. The highest voltage region demonstrated a different deadtime mechanism where the second pulse was reduced in width. During this time the deadtime seemed to be increasing with increasing voltage. This data allows us to gain some unique insight into the phenomenon of GM detector deadtime not reported thus far.

• Journal of Ginseng Research
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• v.19 no.3
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• pp.202-205
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• 1995

We have previously reported that the antagonism of U-50,488H-induced antinociception in mice pretreated with ginseng total saponins (GTS) Ivas abolished by pretreatment with a serotonin precursor, 5-hydroxytryptophan (5-HTP), but not by a noradrenaline precursor, L-dihydroxyphenylalanine (L-DOPA) in the tail flick test. In the present experiments, the effect of the same GTS on the development of tolerance to U-50,488H-induced antinociception was determined. GTS inhibited the development of tolerance to U-50,488H-induced antinociception. The inhibitory effect of GTS on the development of tolerance to U-50,488H-induced antinociception was reversed by 5-HTP, but not by L-DOPA. These findings suggest that the inhibitory effect of GTS on the development of tolerance to U-50,488H-induced antinociception is dependent on serotonergic mechanisms. Key words Ginseng total saponin, U-50,488H, tolerance, serotonin.

• Journal of the Korean Society for Aviation and Aeronautics
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• v.13 no.1
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• pp.20-31
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• 2005

In this study, subsonic flutter analyses have been conducted for a composite smart UAV with T-tail configuration at the critical flight condition. Detailed three-dimensional finite element model for dynamic analysis is constructed including its nonstructural elements corresponding to installed electronic equipments and fuels. Computational structural dynamics and aeroelastic techniques are conducted using MSC/NASTRAN and originally developed in-house codes. The results for fundamental vibration characteristics and flutter instabilities are presented and compared to each other for different fuel conditions.

• Journal of Ginseng Research
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• v.16 no.2
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• pp.93-98
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• 1992

This study examined the Influence of ginseng total saponins (GTS) on the analgestic action and tolerance development of pentazocine in mice. Pentazocine prolonged the latency to response in the tail flick rather than in the tail pinch test. The analgesic effect of pentaEocine was antagonized by naloxone and completely eliminated by pretreatment u·ith f-chlorophenylalanine (PCPA). GTS provented the pentasocine-incuced analgesia ann inhibited the development of tolerance to pentazocine. The antagonistic effect of GTS on the pentazocine-induced analgesia was abolished by 5-HTP, but not by L-DOPA. These results suggest that GTS inhibits the analgesic action of pentazocine by the interaction with serotonergic neuron.

• Publications of The Korean Astronomical Society
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• v.22 no.4
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• pp.183-187
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• 2007

The detection and measurement of faint features in cometary image is generally troublesome due to the high value of the ratio of the brightness of the nucleus to the tail, the large size and low surface brightness of the coma and tail and the disturbing presence of field stars trails. The image processing is based on background removal by median filtering. Sample results are shown for the case study of comet 73P/Schwassmann-Wachmann 3.

• International Journal of Advanced Culture Technology
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• v.10 no.2
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• pp.281-291
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• 2022

Recenlty, the category of luxury wearbles has expanded and the relevant reseach has been scarce. The study tests whether the emotional mechanism regarding luxury wearables within e-tail affects luxury brand perceptions. Furthermore, it tests the moderation effect of gender in the mechanism. A total of 393 responses from U.S. populations were collected through an international research company with using online survey methods. In the results, the positive and direct effect of dominance on positive emotion was significant, and the positive emotion significantly increases perceived brand luxury. However, no direct effect of dominance was found on perceived brand luxury. The moderation effect of gender in the relationship between positive emotion and perceived brand luxury was found positive and significant, but the hypothesized moderation effect of gender was insignificant in the relationship between dominance and perceived brand luxury. Implications and study limitations are discussed.

• Journal of Microbiology and Biotechnology
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• v.7 no.3
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• pp.180-188
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• 1997

Bacillus subtilis C9 was selected by measuring the oil film-collapsing activity and produced biosurfactant in a medium containing glucose as a sole carbon source. The biosurfactant emulsified hydrocarbons, vegetable oils and crude oil, and lowered the surface tension of culture broth to 28 dyne/cm. A biosurfactant, C9-BS produced by B. subtilis C9 was purified by ultrafiltration, extraction with chloroform and methanol, adsorption chromatography, and preparative reversed phase HPLC. Structural analyses, IR spectroscopy, FAB mass spectroscopy, amino acid composition, and NMR analyses, demonstrated that C9-BS was a lipopeptide comprising a fatty acid tail and peptide moiety. The lipophilic part consisting of $C_{14}\;or\;C_{15}$ hydroxy fatty acid was linked to the hydrophilic peptide part, which contained seven amino acids (Glu-Leu-Leu-Val-Asp-Leu-Leu) with a lactone linkage.

• Animal cells and systems
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• v.7 no.3
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• pp.221-225
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• 2003

The tadpole larva of the ascidian Halocynthia roretzi has two sensory pigment cells in its brain vesicle. To elucidate the temporal requirement for FGF signaling in formation of the pigment cells, embryos were treated with an FGF receptor 1 inhibitor, SU5402, or an MEK inhibitor, U0126 during various embryonic stages. In the present study, it is shown that the embryos treated with SU5402 from the 16-cell stage to the early gastrula stage do not form pigment cells, whereas those treated after the early gastrula stage form pigment cells. In pigment cell formation, embryos suddenly exhibited the sensitivity to SU5402 only for 1 h at the neural plate stage(-4 h after the beginning of gastrulation). When U0126 treatment was carried out at various stages between the 8-cell and late neurula stages, the embryos scarcely formed pigment cells. Pigment cell formation occurred when the embryos were placed in U0126 at early tail bud stage. These results indicate that FGF signaling is involved in pigment cell formation at two separate processes during ascidian embryogenesis, whereas more prolonged period is required for MEK signaling.