• 한국표면공학회:학술대회논문집
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• 한국표면공학회 2011년도 춘계학술대회 및 Fine pattern PCB 표면 처리 기술 워크샵
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• pp.75-76
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• 2011

Hot-rolled steel plates of SPHC and SS400 were oxidized at 600, 750 and $900^{\circ}C$ for 2hr in air. With an increase in oxidation temperature, their oxidation rates increased, being accompanied with formation of pores and cracks in the thickened oxide scales that were non-adherent. The SPHC steels that were manufactured by either the arc furnace or the blast furnace displayed similar oxidation rates, indicating that their oxidation rates were insensitive to the manufacturing processes. The medium-carbon SS400 steel displayed a little faster oxidation rates than the low-carbon SS400 steel, indicating that the carbon content did not significantly influence the oxidation rates.

• 한국분말야금학회:학술대회논문집
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• 한국분말야금학회 2006년도 Extended Abstracts of 2006 POWDER METALLURGY World Congress Part 1
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• pp.692-693
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• 2006

Behavior of stoichiometric and near-stoichiometric NiAl at plasma spray deposition, without and with a bond coat, for coating layers realization on a low alloyed steel substrate, has been investigated. In all variants, NiAl particle melting and subsequent welding at the impact with substrate were observed, forming a relatively compact and adherent coating layer with the NiAl stability maintaining - all assuring the coating layer oxidation and corrosion resistance. Good results from these points of view, also validated through corrosion tests, were obtained for 45:55 Ni:Al composition without a bond coat but adopting an Ar protective surrounding of plasma jet.

• 대한금속재료학회지
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• 제48권10호
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• pp.907-913
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• 2010

Hot-rolled steel plates of SPHC and SS400 were oxidized at 600, 750 and $900^{\circ}C$ for 2 hr in air. With an increase in the oxidation temperature, their oxidation rates increased, and this was accompanied by the formation of pores and cracks in the thickened oxide scales, which were non-adherent. SPHC steels manufactured by either an arc furnace or a blast furnace displayed similar oxidation rates, indicating that their oxidation rates were insensitive to the manufacturing process. Medium-carbon SS400 steel displayed somewhat faster oxidation rates than low-carbon SS400 steel, indicating that the carbon content did not significantly influence the oxidation rates.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2021년도 가을 학술논문 발표대회
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• pp.164-165
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• 2021

To prepare the good-adherent and weather-resistant acrylic resin coatings, acrylic resin was prepared by a radical polymerization. Glass transition temperature(Tg) of the acrylic copolymer was fixed at 30℃ and the contents of tertiary amine monomer(DMAEMA) was varied to be 5, 10, 15, 20 wt% respectively. γ-Glycidoxypropyltrimethoxysilane(GPTMS) containing epoxy group was used for curing agents and di-n-butyltindilaurate(DBTDL) was used for drying accelerator. The equivalent ratio of amine to epoxy was 1:1. The prepared coatings exhibited excellent adhesion to various substrates, and various physical properties of the coatings were satisfactory. The gloss retention and color difference were improved at low tertiary amine concentration. The coatings containing 10wt% tertiary amine concentration have especially good weather resistant properties.

• 한국콘텐츠학회논문지
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• 제19권2호
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• pp.277-283
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• 2019

본 연구는 치과용시멘트의 표면특성과 구강세균 부착을 위해 치과용시멘트액에 저분자키토산(Low molecular chitosan: LC)을 무게비로 0, 0.5, 1.0, 2.0 wt%를 첨가하였다. 시멘트의 경화시간과 표면특성으로 표면에너지와 표면거칠기를 평가하였다. 구강세균 부착정도는 구강세균 S. mutans, E.coli 2개의 균주를 이용하여 평가하였다. 실험 결과 경화시간은 LC0.5실험군에서 증가하였으나 통계적 유의한 차이는 나타나지 않았다(p<0.05). 표면거칠기는 LC2.0실험군에서 유의한 차이를 보였으며 구강 세균 부착실험 결과 저분자키토산을 첨가한 실험군 모두 통계적으로 유의하게 낮은 부착양상을 보였다(p<0.05). 본 연구로 저분자키토산의 표면특성과 구강세균 부착억제효과가 있음을 입증하였다. 향후 저분자키토산 첨가양에 따른 효율성과 폭 넓은 물성 연구가 필요할 것으로 사료된다.

• Asian Pacific Journal of Cancer Prevention
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• 제15권8호
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• pp.3397-3401
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• 2014

Determining cell quantity is a common problem in cytology research and anti-tumor drug development. A simple and low-cost method was developed to determine monolayer and adherent-growth cell quantities. The cell nucleus is located in the cytoplasm, and is independent. Thus, the nucleus cannot make contact even if the cell density is heavy. This phenomenon is the foundation of accurate cell-nucleus recognition. The cell nucleus is easily recognizable in images after fluorescent staining because it is independent. A one-to-one relationship exists between the nucleus and the cell; therefore, this method can be used to determine the quantity of proliferating cells. Results indicated that the activity of the histone deacetylase inhibitor Z1 was effective after this method was used. The nude-mouse xenograft model also revealed the potent anti-tumor activity of Z1. This research presents a new anti-tumor-drug evaluation method.

• 한국표면공학회지
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• 제35권4호
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• pp.199-205
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• 2002

TiN and TiAlN films were deposited on SKD 11 steel substrates by an arc ion plating (AIP) technique. The crystallinity and morphology for the deposited films were characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM). The mechanical properties of both films were investigated through the indentation, impact, and wear test. Those films fairly adherent to SKD 11 steel substrate, showed hardness values of 2300 $\pm$ 100kg/$\textrm{mm}^2$ and 3200 $\pm$ 100kg/$\textrm{mm}^2$ with a load of 25g, respectively. During impact test, TiAlN films showed much superior impact wear resistance to TiN films. It could be suggested that the TiN films was failed relatively by plastic deformation with oxidation during impact test, while TiAlN films was failed by brittle fracture and resisted the oxidation by the impact energy. The friction coefficient of TiAlN films became lower than that of TiN films at high sliding speed condition although it was higher than that of TiN films at low speed. Therefore, TiAlN films was suggested to be more advantageous than TiN films for high speed machining fields.

• The Korean Journal of Ceramics
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• 제3권1호
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• pp.57-61
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• 1997

The effects of pH of solution on structural, electrical, and optical properties of CdS thin films prepared by solution growth method were investigated. With increasing pH of the solution, both crystallinity and transmittance of CdS thin film were deteriorated due to impurities and CdS particles, which were produced by homogeneous nucleation and adsorbed on the surface of CdS thin films. The films were strongly adherent to substrates and has low resistivity of 10~$10^2{\omega}cm$ regrardless of deposition conditions. After annealing at 30$0^{\circ}C$ in Ar atmosphere, the resistivity decreased due to desorption of impurity ions as well as the formation of S vacancies, but after annealing above 35$0^{\circ}C$ it increased by an agglomeration of S vacancies. After annealing in air atmosphere, the film resistivity increased because of the formation of oxide particle in grain boundaries.

• Journal of Korean Biological Nursing Science
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• 제14권1호
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• pp.66-75
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• 2012

Purpose: This study was conducted to measure medication adherence and perceptions of anticoagulation therapy and its relationship to patients taking warfarin. Methods: in a cross-sectional survey, 150 patients taking warfarin who had visited an outpatient clinic of a cardiovascular center in Seoul were included as research subjects. Medication adherence was measured using a visual analogue rating scale (VAS). Barriers and attitudes toward adherence, and oral anticoagulation knowledge, were measured using a structured questionnaire. Participants' medical records also were reviewed to identify clinical characteristics. Results: About one third of the participants (30.7%) reported medication adherence as 100%. The major barriers to adherence were identified as "Forgetting the time of medication" and "Not carrying their medication". Overall attitudes toward medication adherence were high, but oral anticoagulation therapy knowledge was low. To determine the relationship of medication adherence and perceptions of anticoagulation therapy, participants were stratified into three groups, based on their medication adherence levels (high adherence, moderate adherence, low adherence). Participants in the high adherent group more likely to be older (OR: 1.04, 95% CI: 1.005-1.071) and to have positive attitudes toward medication adherence (OR: 1.12, 95% CI:1.013-1.229) compared to the other two groups. Conclusion: The results show that age and attitude exerts significant influence on medication adherence in patients taking warfarin.

• Journal of Periodontal and Implant Science
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• 제30권2호
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• pp.429-442
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• 2000

Based on current evidence in the literature, it is known that endotoxin is a weakly adherent surface phenomenon and that power-driven instruments can be used to accomplish definitive root detoxification and maximal wound healing without overinstrumentation of root and without extensive cementum removal. And one of the newly developed curette tips used with low power of piezoelectric ultrasonic scaler, is effective to remove calculus and not to remove the excessive cementum. The purpose of this study is therefore, to assess the influence of ultrasonic power and various working parameters on root substitute removal when instrumentation is performed with the curette tip on piezoelectric ultrasonic scaler. This study assessed defect depth, width and area resulting from instrumentation using a piezoelectric ultrasonic scaler with a curette type tip in vitro to acrylic resin block as a root substitute. The working parameters was standardized by the sledge device which controls lateral force(0.5 N, 1 N, 2 N) and instrumentation time(5 sec, 10 sec, 20 sec) and power setting was adjusted 0,2,4,8 in P mode. Power setting had the greatest influence on defect depth compared to lateral force and instrumentation time(standardized regression parameter estimates${\pm}$standard error, $0.37{\pm}0.02$, $0.19{\pm}0.02$, $0.07{\pm}0.02$). The effects on defect area also greatest for power setting($0.57{\pm}0.03$) compared to lateral force and instrumentation time($0.33{\pm}0.03$, $0.12{\pm}0.03$). The effect of the power setting on the defect width($0.15{\pm}0.01$) is not so great as defect depth or defect area compared to lateral force($0.12{\pm}0.01$) and effect of instrumentation time is minimal($0.02{\pm}0.01$). It could be concluded that the power setting has the greatest influence on the defect depth and area in curette type tip with low power of piezoelectric ultrasonic device. Many parameters can be adjusted in various situation in clinical use of piezoelectric ultrasonic scaler but the power setting is the first parameter to be adjusted.