• Textile Coloration and Finishing
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• v.29 no.3
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• pp.131-138
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• 2017

Most of high performance fabrics for the car racing protective clothing have been developed to have thermal resistance, flame retardant property, impact resistance and anti-frictional properties to protect the racer from the crucial accident. In this study, the meta-aramid fabric, which has inherent flame retardant, was coated with nanoparticles of SiC to enhance the impact resistance and anti-friction properties. Uniform coating of the nanoparticles onto the fabrics was obtained by using tape casting method. As the experimental parameters, size and content of the SiC nanoparticle were varied with the coating conditions of the fabric surface. The effects of the nanoparticle coating on the properties of meta-aramid fabric were examined with various instrumental analyses such as SEM, tensile strength and abrasion test.

• Food Science and Biotechnology
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• v.18 no.6
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• pp.1322-1329
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• 2009

The present study focused on the effects of peel contact on the volatile compounds of orange wines. The volatile compounds were analyzed by sensory and instrumental analyses. Solid-phase microextraction (SPME) was used for extraction of volatile compounds. A total of 19 and 27 volatile compounds were identified in without and with peel contact wines respectively. Esters were quantitatively the dominant group of volatile compounds in without peel contact wines, while terpenes were the most abundant compounds in peel contact wines. Totally 11 and 14 new formed compounds were found in without and with peel contact wines, mainly were esters, alcohols, and acids. According to sensory analysis, the peel contact wine showed a more citrus-like and fruity aroma than the wines without peel contact.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2014.11a
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• pp.304-304
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• 2014

Quaternary Ti-Al-Si-N films were deposited on WC-Co substrates by a hybrid deposition system of arc ion plating (AIP) method for Ti-Al source and DC magnetron sputtering technique for Si incorporation. The synthesized Ti-Al-Si-N films were revealed to be composites of solid-solution (Ti,Al)N crystallites and amorphous $Si_3N_4$ by instrumental analyses. The Si addition in Ti-Al-N films affected the refinement and uniform distribution of crystallites by percolation phenomenon of amorphous silicon nitride, similarly to Si effect in TiN film. As the Si content increased up to about 9 at.%, the hardness of Ti-Al-N film steeply increased from 30 GPa to about 50 GPa. The highest microhardness value (~50 GPa) was obtained from the Ti-Al-Si-N film having the Si content of 9 at.%, the microstructure of which was characterized by a nanocomposite of $nc-(Ti,Al)N/a-Si_3N_4$.

• Macromolecular Research
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• v.13 no.6
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• pp.491-498
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• 2005

Fluorene-containing, spiro-type, conjugated polymers were synthesized via the cyclopolymerization of dipropargylfluorenes (2-substituted, X=H, Br, Ac, $ NO_{2}$) with various transition metal catalysts. The polymerization of dipropargylfluorenes proceeded well using Mo-based catalysts to give a high polymer yield. The catalytic activities of the Mo-based catalysts were found to be more effective than those of W-based catalysts. The palladium (II) chloride also increased the polymer yield of the polymerization. The polymer structure of poly(dipropargylfluorene)s was characterized by such instrumental methods as NMR ($^{1}H_{-}$, $^{13}C_{-}$), IR, UV-visible spectroscopies, and elemental analysis as having the conjugated polymer backbone bearing fluorene moieties. The $^{13}C_{-}$NMR spectral data on the quaternary carbon atoms in polymers indicated that the conjugated cyclopolymers have the six-membered rings majorly. The poly(dipropargylfluorene) derivatives were completely soluble in halogenated and aromatic hydrocarbons such as methylene chloride, chloroform, benzene, toluene, and chlorobenzene. The poly(dipropargylfluorene) derivatives were thermally more stable than poly(dipropargylfluorene) itself, and X-ray diffraction analyses revealed that the polymers are mostly amorphous. The photoluminescence peaks of the polymers were observed at about 457-491 nm, depending on the substituents of fluorene moieties.

• Journal of the Korean institute of surface engineering
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• v.39 no.3
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• pp.110-114
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• 2006

In this work, comparative studies on microstructure and mechanical properties between $Mo_2N$ and Mo-Si-N coatings were conducted. Ternary Mo-Si-N coatings were deposited on AISI D2 steel substrates by a hybrid method, where AIP technique was combined with a magnetron sputtering technique. Instrumental analyses of XRD, HRTEM, and XPS revealed that the Mo-Si-N coatings must be a composite consisting of fine $Mo_2N$ crystallites and amorphous $Si_3N_4$. The hardness value of Mo-Si-N coatings significantly increased from 22 GPa of $Mo_2N$ coatings to about 37 GPa with Si content of 10 at.% due to the refinement of $Mo_2N$ crystallites and the composite microstructure characteristics. The average friction coefficient of the Mo-Si-N coatings gradually decreased from 0.65 to 0.4 with increasing Si content up to 15 at.%. The effects of Si content on microstructure and mechanical properties of Mo-N coatings were systematically investigated.

• Journal of the Korean institute of surface engineering
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• v.39 no.6
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• pp.245-249
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• 2006

In this study, ternary Ti-Mo-N and new quaternary Ti-Mo-Si-N coatings were synthesized on steel substrates(AISI D2) and Si wafers by a hybrid coating system of arc ion plating (AIP) using Ti target and d.c. magnetron sputtering technique using Mo and Si targets in $N_2/Ar$ gaseous mixture. Ternary Ti-Mo-N coatings were substitutional solid-solution of (Ti, Mo)N and showed maximum hardness of approximately 30 GPa at the Mo content of ${\sim}10$. %. The Ti-Mo-Si-N coating with the Si content of 8.8 at. % was a composite consisting of fine (Ti, Mo)N crystallites and amorphous $Si_3N_4$ phase. The hardness of the Ti-Mo-Si(8.8 at. %)-N coatings exhibited largely increased hardness value of ${\sim}48$ GPa due to the microstructural evolution to the fine composite microstructure and the refinement of (Ti, Mo)N crystallites. The average friction coefficient of the Ti-Mo-Si-N coatings largely decreased with increase of Si content. The microstructures of Ti-Mo-Si-N coatings were investigated with instrumental analyses of XRD, XPS, and HRTEM in this work.

• Journal of the Korean institute of surface engineering
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• v.40 no.6
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• pp.279-282
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• 2007

Cr-Mo-Si-C-N coatings were deposited on steel and Si wafer by a hybrid system of AIP and sputtering techniques using Cr, Mo and Si target in $Ar/N_2/CH_4$ gaseous mixture. Instrumental analyses of XRD and XPS revealed that the Cr-Mo-Si-C-N coatings must be a composite consisting of fine(Cr, Mo and Si)(C and N) crystallites and amorphous $Si_3N_4$ and SiC. The hardness value of Cr-Mo-Si-C-N coatings significantly increased from 41 GPa of Cr-Mo-C-N coatings to about 53 GPa with Si content of 9.3 at.% due to the refinement of (Cr, Mo and Si)(C and N) crystallites and the composite microstructure characteristics. A systematic investigation of the microstructures and mechanical properties of Cr-Mo-Si-C-N coatings prepared with various Si contents is reported in this paper.

• Smart Media Journal
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• v.1 no.4
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• pp.72-78
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• 2012

SNS supports the formation of relationships between users in common interests and provides services allowing for clique management, sharing contents, and so on. It also has common functions such as acting as primary platforms smoothing the sharing and distribution by combination with various contents. Hence, questionnaire has been conducted to users of all of Twitter, Facebook and KakaoStory, and the factors affected by each service are presented by statistical analyses of the survey and the results are resolved by dividing them into complete and instrumental social capital. This study will be able to provide a standard for users to select SNS according to their purposes and contribute to development of new SNS or improvement of existing ones.

• Journal of Digital Convergence
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• v.18 no.9
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• pp.297-305
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• 2020

The purpose of this study was to identify the factors associated with subjective age among community-dwelling older adults in South Korea. Cross-sectional analyses were performed on 8,040 older adults aged 65 years and over from the 2017 National Survey of Older Koreans. We used univariable analysis and multivariable analysis by the logistic regression test. The significant factors associated with subjective age in older adults were gender, education level, living arrangements, limitation of instrumental activities of daily living, number of chronic diseases, perceived health status, depression, and current economic activity. Based on the results of this study, nursing intervention will be needed to lower subjective age. This study may contribute to the older adults to have a healthy and successful old age.

• Journal of Families and Better Life
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• v.14 no.2
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• pp.111-126
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• 1996

Debt was defined as all kinds of borrowings made by families in including credit card debt. The purpose of the study was to investigate the effects of family debt management on financial satisfaction. A model of debt management and financial satisfaction was developed based on the Deacon-Firebaugh's systems approach to family resource management and the variables comprising input throughput and output were based on the theoretical background asnd previous researches. Data were collected from 763 households' money managers residing in Seoul during Summer of 1995 and the statistical methods utilized included correlation coefficient multiple regression and path analyses. It was responded about 82% of the households had been indebted indicating the use of debt being a general way of living in this society. The results showed that financial satisfaction lowered with larger amount of monthly debt payment and with their uncertiainty regarding their capability to repay debt. The input which exerted direct effects on financial satisfaction were income asset financial expectations and family life cycle. And consumption demand on debt and easiness in extending credit had strong indirect effects on financial satisfaction via the throughput variables. The most powerful predictor of financial satisfaction via the throughput variables. The most powerful predictor of financial satisfaction was perceived difficulty in managing debt which was the instrumental output.