• 한국염색가공학회지
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• 제29권3호
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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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• 제18권6호
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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.

• 한국표면공학회:학술대회논문집
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• 한국표면공학회 2014년도 추계학술대회 논문집
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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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• 제13권6호
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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.

• 한국표면공학회지
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• 제39권3호
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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.

• 한국표면공학회지
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• 제39권6호
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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.

• 한국표면공학회지
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• 제40권6호
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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.

• 스마트미디어저널
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• 제1권4호
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• pp.72-78
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• 2012

SNS는 인터넷 상에서 공통의 관심사를 지니고 있는 사용자들 간의 관계형성을 지원하고, 이렇게 형성된 지인 관계를 바탕으로 인맥 관리, 정보 및 콘텐츠 공유 등 다양한 활동을 할 수 있도록 지원하는 서비스이다. SNS는 다양한 콘텐츠와의 결합을 통하여 네트워크를 통해 형성된 지인 관계를 기반으로 공유와 배포를 원활하게 하는 주요 플랫폼으로 활용되는 등 몇 가지의 공통적인 기능을 가지고 있다. 이에 트위터, 페이스북, 카카오스토를 모두 사용하고 있는 사용자들을 대상으로 설문조사를 진행하였으며, 설문에 응답한 자료를 통계 내어 각각의 서비스가 영향을 주는 요인들은 어떤 것인지 완성적 사회자본과 도구적 사회자본으로 나누어 분석한 결과를 제시하였다. 이 연구는 사용자들의 목적에 따라 SNS를 선택하는 기준이 되고, 새로운 SNS를 개발하거나 기존의 서비스를 발전시키는데 기여할 수 있을 것이다.

• 디지털융복합연구
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• 제18권9호
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• pp.297-305
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• 2020

본 연구의 목적은 한국 지역사회 거주 노인의 주관적 연령과 관련된 요인을 규명하는 것이다. 본 연구는 2017년도 노인실태조사에 참여한 65세 이상 노인 8,040명을 대상으로 이차 분석한 횡단 연구이다. 노인의 주관적 연령과 관련된 요인을 규명하기 위해 단변량 로지스틱 회귀분석에서 유의한 변수만 추출하여 다변량 로지스틱 회귀분석으로 분석하였다. 본 연구결과, 성별, 학력, 거주형태, IADL 제한, 만성질환 수, 지각된 건강 상태, 우울 및 현재 경제활동 여부가 노인의 주관적 연령과 관련이 있는 것으로 나타났다. 본 연구결과에 근거하여 주관적 연령을 낮추기 위한 간호중재가 이루어져야 할 것이다. 본 연구를 통해 노인들이 건강하고 성공적인 노후를 보내는 데 기여할 수 있을 것이다.

• 가정과삶의질연구
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• 제14권2호
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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.