• Journal of Powder Materials
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• v.15 no.5
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• pp.352-358
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• 2008

The present study focused on the synthesis of a bismuth-antimony-tellurium-based thermoelectric nanopowders using plasma arc discharge process. The chemical composition, phase structure, particle size of the synthesized powders under various synthesis conditions were analyzed using XRF, XRD and SEM. The powders as synthesized were sintered by the plasma activated sintering. The thermoelectric properties of sintered body were analyzed by measuring Seebeck coefficient, specific electric resistivity and thermal conductivity. The chemical composition of the synthesized Bi-Sb-Te-based powders approached that of the raw material with an increasing DC current of the are plasma. The synthesized Bi-Sb-Te-based powder consist of a mixed phase structure of the $Bi_{0.5}Sb_{1.5}Te_{3}$, $Bi_{2}Te_{3}$ and $Sb_{2}Te_{3}$ phases. This powder has homogeneous mixing state of two different particles in an average particle size; about 100nm and about 500nm. The figure of merit of the sintered body of the synthesized 18.75 wt.%Bi-24.68 wt.%Sb-56.57 wt.%Te nanopowder showed higher value than one of the sintered body of the mechanically milled 12.64 wt.%Bi-29.47 wt.%Sb-57.89 wt.%Te powder.

• The Research Journal of the Costume Culture
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• v.21 no.6
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• pp.793-809
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• 2013

This study examined the trend and aesthetic value of image fashion of the 21st century through empirical case study with image media as fashion communication tool. This research is intended to provide the basic material for both better comprehension of image fashion as emotional medium in the modern fashion and more activated research on interactivity and communication in the fashion communication area by examining how fashion designers deliver their design philosophy, thought and vision via image fashion. For the research method, the theoretical study was realized about image media and fashion communication with focus on related literature and precedent research. Also, the empirical study was performed about image fashion covering 2005 through 2012 by the group of fashion film, fashion animation, and video look-book. Fashion image in the research was developed into various layouts that include the story based or non-story based creative images, many kinds of episode or behind-the-scenes story in the prep course of collection, designer's personal life or product world, or re-cutting course after collection. It also played a communicative role for public relation of new product ad, concept conveyance of seasonal collections, means as online collection to substitute for the existing offline collections, and better understandings of designer or fashion brand. Aesthetic values derived from case analysis of image fashion in the modern fashion of 21st century appeared in the form of trans-boundary as convergence art, fantasy in harmony with virtuality and reality, and interactivity among the humans, image media and fashions.

• Journal of the Institute of Electronics Engineers of Korea TE
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• v.39 no.3
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• pp.8-14
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• 2002

UV, heat, and discharge treatments are arbitrary simulated for finding out the initiations and processes of surface degradation on the polymer surface. Especially, this study is focused on the inter-relation between chemical changes and electrical properties. In contact angle to measure the change of activated degree, that of polymers surface shows a slight hydrophobicity of 73$^{\circ}$~91$^{\circ}$. But, discharge treatment and UV treatment of 300 nm wavelength changed it to the hydrophilic one with the decrease of contact angle, 13.8$^{\circ}$ and 20$^{\circ}$ respectively. Thermal-treatment and UV treatment of 430~500 nm wavelength changed the surface to the hydrophobic one with the increase of contact angle, 90$^{\circ}$ and 80.1$^{\circ}$ respectively.  

• Journal of Ginseng Research
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• v.44 no.3
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• pp.453-460
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• 2020

Background: BIOGF1K, a fraction of Panax ginseng, has desirable antimelanogenic, anti-inflammatory, and antiphotoaging properties that could be useful for treating skin conditions. Because its potential positive effects on allergic reactions in skin have not yet been described in detail, this study's main objective was to determine its efficacy in the treatment of atopic dermatitis (AD). Methods: High-performance liquid chromatography was used to verify the compounds in BIOGF1K, and we used the (3-4-5-dimethylthiazol-2-yl)-2-5-diphenyltetrazolium bromide method to determine its cytotoxicity in RBL-2H3 and HMC-1 cell lines. RBL-2H3 cells were induced using both anti-DNP-IgE/DNP-BSA and calcium ionophore (A2187) treatments, whereas HMC-1 cells were induced using A2187 alone. To measure mast cell degranulation, we performed histamine (enzyme-linked immunosorbent assay) and β-hexosaminidase assays. To quantify interleukin (IL)-4, IL-5, and IL-13 levels in RBL-2H3 cells, we performed quantitative polymerase chain reaction (PCR); to quantify expression levels of IL-4 and IL-13 in HMC-1 cells, we used semiquantitative reverse transcription polymerase chain reaction (RT-PCR). Finally, we detected the total and phosphorylated forms of extracellular signal-regulated kinase, p-38, and c-Jun N-terminal kinase proteins by immunoblotting. Results: BIOGF1K decreased the AD response by reducing both histamine and β-hexosaminidase release as well as reducing the secretion levels of IL-4, IL-5, and IL-13 in RBL-2H3 cells and IL-4 and IL-13 in HMC-1 cells. In addition, BIOGF1K decreased MAPK pathway activation in RBL-2H3 and HMC-1 cells. Conclusions: BIOGF1K attenuated the AD response, hence supporting its use as a promising and natural approach for treating AD.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.45 no.1
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• pp.63-70
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• 2017

In this paper, we design and fabricate a de-orbiter using drag-sail and evaluate deployment characteristics. Without employing an actuator to deploy, the de-orbiter is activated by the SMA wire based the release mechanism and driven by the restoring force of the tape-spring. For efficient storage and deployment of drag-sail, an origami method of original ISO flasher is chosen and low priced mylar film is used as the material of the drag-sail. In addition, through the fault tree analysis method which is one of the one-shot device reliability evaluation methods, we confirm the reliability of the de-orbiter(0.997572) and the Roller failure has the highest criticality. Finally, we find feasibility of the proposed de-orbiter through the deployment demonstration of drag-sail.

• KSBB Journal
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• v.15 no.4
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• pp.370-374
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• 2000

Some bacterial strains isolated from activated sludges and media and type cultures were cultivated in a pharmaceutical wastewater and a paperboard wastewater and added during batch treatment of those wastewaters in order for these strains to increase the treatment efficiency. Bacillus sp(PC-3) isolated from the charcoal media of the pharmaceutical wastewater plant grew remarkably over there strains in that wastewater and the viable cell count after 24hr cultivation was $1.1{\times}10^6m/L$. Bacillus subtills KCTC 1028 a type strain grew best in the paperboard wastewater and the viable cell count after 24hr cultivation was $1.1{\times}10^7m/L$. Addition of PC-3 in a batch treatment of the pharmaceutical wastewater increased COD removal by 18% after 8 day. And addition of Bacillus subtills KCTC 1028 in a batch treatment of the paperboard wastewater increased COD removal by 14% only after 24hy Bacillus subtills DCTC 1028 was though to be able to be produced economically using alcohol distillery wastewaters from starch material.

• Journal of Marine Bioscience and Biotechnology
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• v.11 no.2
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• pp.71-80
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• 2019

Previously, agar obtained from Gelidum sp. has a small molecular weight and has the disadvantage of inherent viscosity properties and poor functionality as a dietary fiber. In order to improve aforementioned disadvantages, agar having a fluidity that can be added to food at a higher concentration that a powder agar having a gelling property at low concertation was manufactured. In addition, the anti-inflammatory activity of agar hydrolysates was evaluated to confirm their potential as a functional material. As a result, agar hydrolysates significantly reduced NO levels secreted by LPS-activated macrophages and inhibited the expression of iNOS and COX-2, which are inflammatory mediators that regulates NO secretion in macrophages. Furthermore, in in vivo zebrafish embryos model results demonstrated significant reduction of LPS induced NO production after the treatment of agar hydrolysate hydrolyzed for 360 min. In addition, ROS production and cell death by stresses were also reduced in LPS-exposed embryos after the treatment of agar hydrolysis product hydrolyzed for 360 min. Taken together, agar hydrolysate hydrolyzed for 360 min can be easily added into food due to their fluidity and used as a food ingredient that inhibits inflammation due to their anti-inflammatory property.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.31 no.4
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• pp.44-52
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• 2003

Shape memory alloys (SMA) are often used in smart structures as active components. Their ability to provide large recovery forces and displacements has been useful in many applications, including devices for artificial muscles, active structural acoustic control, and shape control. Based on the 3-dimensional SMA constitutive equation in this paper, the radial displacement control of externally pressurized circular and semicircular composite cylinders under external pressure with a thin SMA layer bonded on its inner surface or inserted between composite layers in investigated using 3-dimensional finite element analysis. Upon actuation through resistive heating, SMAs start to transform from martensitic into austenitic state, simultaneously recover the prestrain, and thus cause the composite cylinders to go back to their original shapes of the cylinder cross-sections.

• Korean Journal of Pharmacognosy
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• v.50 no.4
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• pp.291-298
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• 2019

Phlox subulata is a perennial herbaceous flower and is a member of the Polemoniaceae family. This plant is known to resist to various stresses including salt, drought, heat, and cold stresses. In this investigation, we evaluated the ant-inflammatory effect of the methanolic extract of P.subulata(PSM) on lipopolysaccharide(LPS)-induced RAW264.7 macrophages and BV2 microglia. PSM reduced the production of nitric oxide(NO) in LPS-stimulated both RAW264.7 and BV2 cells, but did not affect to the production of prostaglandin E2(PGE₂). It inhibited the expression of inducible nitric oxide synthase(iNOS) and cyclooxygenase(COX)-2 in both cells. In addition, PSM suppressed the production of pro-inflammatory cytokines including interleukin(IL)-6 and tumor necrosis factor(TNF)-α. These inhibitory effects were contributed by inactivation of nuclear factor kappa B(NF-κB) and mitogen-activated protein kinases(MAPKs) pathways by PSM. Thus, these results suggested that P.subulata can be a candidate material to treat inflammatory diseases.

• Journal of the Mineralogical Society of Korea
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• v.16 no.2
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• pp.125-133
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• 2003

Saponite was synthesized from talc by hydrothermal method. The starting material was prepared by adding ($NO_3$)$Al_3$$.$$9H_2$O and Mg($NO_3$)$_2$$.$$6H_2$O solution to the talc powder. which was previously activated in air at 800 $^{\circ}C$ together with $Na_2$$CO_3$. The alkalinity of the solution was controlled by $NH_4$OH solution. The autoclaving was carried out in the closed stainless steel vessel (about 1 liter) for 40 hours under the pressure of 25 kgf/$\textrm{cm}^2$ at $ 230^{\circ}C$ The characterization of the reaction product shows that saponite was crystallized successfully. After the experimental results, pressure was not sensitive parameter in the range of 25 ∼ 75 kgf/$\textrm{cm}^2$, but longer reaction time results in better crystallinity.