• Journal of the Korean Society for Nondestructive Testing
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• v.30 no.5
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• pp.411-422
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• 2010

Self-sensing on micro-failure, dispersion degree and relating properties, of carbon nanotube(CNT)/epoxy composites, were investigated using wettability, electro-micromechanical technique with acoustic emission(AE). Specimens were prepared from neat epoxy as well as composites with untreated and acid-treated CNT. Degree of dispersion was evaluated comparatively by measuring volumetric electrical resistivity and its standard deviation. Apparent modulus containing the stress transfer was higher for acid-treated CNT composite than for the untreated case. Applied cyclic loading responded well for a single carbon fiber/CNT-epoxy composite by the change in contact resistivity. The interfacial shear strength between a single carbon fiber and CNT-epoxy, determined in a fiber pullout test, was lower than that between a single carbon fiber and neat epoxy. Regarding on micro-damage sensing using electrical resistivity measurement with AE, the stepwise increment in electrical resistivity was observed for a single carbon fiber/CNT -epoxy composite. On the other hand, electrical resistivity increased infinitely right after the first carbon fiber breaks for a single carbon fiber/neat epoxy composite. The occurrence of AE events of added CNT composites was much higher than the neat epoxy case, due to micro failure at the interfaces by added CNTs.

• Journal of the Korean Chemical Society
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• v.49 no.3
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• pp.288-291
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• 2005

• Bulletin of the Korean Chemical Society
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• v.26 no.12
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• pp.2051-2053
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• 2005

• Bulletin of the Korean Mathematical Society
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• v.39 no.2
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• pp.347-357
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• 2002

In this paper, we study the concepts of isocompactness and cl-isocompactness. We generalize a pure space defined by Arhangelskii and get some results on initially K-compact spaces. We also consider open problems related to isocompactness and cl-isocompactness.

• 한국정보디스플레이학회:학술대회논문집
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• 2006.08a
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• pp.577-582
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• 2006

Unlike the case of $Ir(ppy)_3$, various aggregates of PtOEP including dimer are formed in PtOEP-doped films and neat film. Such a difference is due to difference of competition among solid state solvation effect, dipole-dipole interactions between dopant molecules, and intermolecular covalent bonding.

• Bulletin of the Korean Chemical Society
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• v.34 no.5
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• pp.1547-1550
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• 2013

• Journal of the Korean Chemical Society
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• v.28 no.1
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• pp.34-40
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• 1984

The reorientational motion of $C_6F_6$ in neat liquid is investigated in the temperature range 293∼333K by analyzing ${\nu}_2$ and ${\nu}_16$ bands of its Raman spectrum. Diffusion constants for the tumbling ($D_{\bo}$) and spinning ($D_{\parallel}$) motions are determined. The reorientation of the molecule seems to be distinctly anisotropic. Based on the hydrodynamic model, the tumbling motion of the figure axis of $C_6F_6$ is largely diffusional. On the other hand, the spinning motion of the same axis looks mostly inertial.

• Journal of the Korean Ceramic Society
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• v.53 no.1
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• pp.24-33
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• 2016

The grafting reaction for maleic anhydride (MA) onto high density polyethylene (HDPE) was investigated from solution process with initiators. The chemical modification of neat HDPE was carried out with various contents of MA (3-21 wt.%) and initiator (0.2-1 wt.%) at different temperature ($80-130^{\circ}C$). The grafting degree was obtained from the titration and the highest grafting degree was 3.1%. The grafting degree increased as the content of MA and initiator increased, however, the highest grafting degree was demonstrated for a particular content of MA and initiator. In the non-isothermal crystallization kinetics, the Ozawa model was unsuitable method to investigate the crystallization behavior of MA onto HDPE, whereas the Avrami and Liu models found effective. The crystallization rate was accelerated as the cooling rate increased, but postponed by combination of MA onto neat HDPE backbone.

• Membrane and Water Treatment
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• v.9 no.6
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• pp.385-392
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• 2018

Poly vinyl chloride (PVC) was chemically modified, and used for ultrafiltration to analyze the performance. Non-solvent induced phase separation (NIPS) method was used to prepare membranes. The neat PVC membrane was casted and used as a control membrane. Modified membrane was prepared by reacting PVC with ethanolamine (EA) in the casting solution (labeled as CM-PVC). Pure water permeability (PWP) was evaluated by measuring pure water flux. Humic acid was used as model foulant solute to analyze flux and rejection ability of membranes. Flux and rejection data of neat and modified membranes were compared to prove the improvement in the filtration performance. The experimental results showed that for PVC and CM-PVC, PWP was calculated to be ~64 and ${\sim}143L/m^2{\cdot}h$, respectively, and the rejection of humic acid was found to be 98% and 100%, respectively. TGA was carried out to analyze the effect of chemical modification on the thermal stability of polymer. FT-IR analysis was another characterization technique used for the comparative study.

• Journal of the Korea Fashion and Costume Design Association
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• v.14 no.3
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• pp.93-109
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• 2012

The purpose of this study is to examine the modern men's fashion coordination to see the image in the center of TV dramas in terms of Habitu that is formed within hierarchy and class. The subjects range is included fashion style, color, accessories, hairstyle and appearance. 950 pictures used in the analysis sheet. In research methods, content analysis and basic statistics were used. The results of this study were as follows. First, the hierarchy image formed by Habitus is significant difference. The upper layer is coordinating elite luxurious and prestigious image of the fashion styles. The middle layer is coordinating neat and capable image. The lower layer does not care about the appearance and image appearing weary life is coordinating. Second, the class image formed by Habitus, CEO often interests in fashion image coordination. Senior executive is represented clean and luxurious image. General white color dresses in a suite such as office look. Blue color does not care about the fashion coordination and is expressed an easy dress for labor. Architects of the unstructured free-spirited image is represented. Physician and resident physician dress in shirts, no pattern tie, pants, robe. And they is coordinating neat and tidy attire to represent professional and reliable image.