• 한국재료학회:학술대회논문집
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• 한국재료학회 2005년도 춘계학술발표대회 및 제8회 신소재 심포지엄 논문개요집
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• pp.240-240
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• 2005

• 마이크로전자및패키징학회지
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• 제19권2호
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• pp.1-5
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• 2012

Long-term reliability of Si photovoltaic modules is a crucial issue for the cost-reduction on the power-supply system. To elevate this reliability, several environmental tests have been created as qualification and certification procedures. This paper gives an overview about recent researches of reliability tests for Si photovoltaic modules.

• 한국초전도ㆍ저온공학회논문지
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• 제17권3호
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• pp.1-4
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• 2015

Production of $MgB_2$ film on metallic Hastelloy with SiC as the buffer layer was achieved by means of hybrid physical-chemical vapor deposition technique, whereas SiC buffer layers with varied thickness of 170 and 250 nm were fabricated inside a pulsed laser deposition chamber. Superconducting transition temperature and critical current density were verified by transport and magnetic measurement, respectively. With SiC buffer layer, the reduced delaminated area at the interface of $MgB_2$-Hastelloy and the slightly increased $T_c$ of $MgB_2$ tapes were clearly noticed. It was found that the upper critical field, the irreversibility field and the critical current density were reduced when $MgB_2$ tapes were buffered with SiC buffer layer. Clarifying the mechanism of SiC buffer layer in $MgB_2$ tape in affecting the superconducting properties is considerably important for practical applications.

• 한국전기전자재료학회논문지
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• 제19권1호
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• pp.1-6
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• 2006

High performance $Si_{0.8}Ge_{0.2}$ heterostructure metal-oxide-semiconductor field effect transistors (MOSFETs) were fabricated using well-controlled delta-doping of boron and $Si_{0.8}Ge_{0.2}$/Si heterostructure epitaxal layers grown by reduced pressure chemical vapor deposition. In this paper, we report 1/f noise characteristics of the SiGe pMOSFETs measured under various bias conditions of the gate and drain voltages changing in linear operation regions. From the noise spectral density, we found that the gate and drain voltage dependence of the noise represented same features, as usually scaled with $f^{-1}$ However, 1/f noise was found to be much lower in the device with boron delta-doped layer, by a factor of $10^{-1}_10^{-2}$ in comparison with the device fabricated without delta-doped layer. 1/f noise property of delta-doped device looks important because the device may replace bipolar transistors most commonly embedded in high-frequency oscillator circuits.

• 근관절건강학회지
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• 제28권2호
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• pp.174-182
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• 2021

Purpose: This study is a secondary data analysis study to identify factors related to the quality of life of people aged 65 y or older, according household type. Methods: In 2019, the study extracted the data from the elderly participants (65 y of age or older) from G province Community Health Survey. The data were compiled and analyzed in a composite sample. Results: The quality of life was lowest among single people, grandparents-grandchildren (F=39.88, p<.001). Variables that significantly influenced quality of life in single-person households were basic security(β=-.03, p=.002), high-risk drinking (β=.04, p=.002), number of day to walk (β=.01, p<.001), diabetes mellitus (β=-.03, p<.001), depression (β=-.02, p<.001), and contact frequency (β=.00, p<.001). Variables that significantly influenced grandparents-grandchildren households were basic security (β=.03, p<.001), smoking(β=-.02, p<.001), number of day to walk (β=.00, p<.001), hypertension (β=-.01, p=.009), diabetes mellitus (β=-.04, p<.001), cognitive impairment (β=-.02, p<.001), depression(β=-.02, p<.001), contact frequency (β=.01, p<.001), and neighborhood trust (β=.02, p<.001). Conclusion: In this study, there were differences in health-related quality of life for each type of household, and various support systems are needed in their social networks to suit their characteristics.

• 대한소아치과학회지
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• 제36권1호
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• pp.62-70
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• 2009

본 연구는 최근 시판되고 있는 4종의 복합레진 Palfique Estelite $sigma^{{R}}$ (Tokuyama Dental Corp., Tokyo, Japan), $Z-350^{{R}}$ (3M ESPE, USA), Ceram X duo $E3^{{R}}$, Ceram X duo $D3^{{R}}$ (Dentsply, Konstanz, Germany)이 3가지 액체 환경에 노출될 때 시간에 따라 필러의 용출 양상이 변하는지 알아보고 이를 비교 분석하였다. 필러의 용출량을 평가하기 위해 내경 10mm, 두께 3mm인 테프론 몰드를 이용하여 시편을 제작하였다. 각각의 시편을 5ml의 0.1N NaOH 용액, 증류수, 인공타액이 담긴 폴리에틸렌 용기에 담구고 $37{\circ}C$ 오븐에서 보관하였다. Si, Ba의 용출량을 알아보기 위해 ICP-AE 기기를 이용하여 0.1N NaOH 용액에 담군 시편은 2주 후에, 증류수와 인공타액에 담군 시편은 1개월 간격으로 5회에 걸쳐 정량 분석하여 다음과 같은 결과를 얻었다. 1. 0.1N NaOH에서 필러의 용출량은 모든 시편에 대해서 유의하게 높았다 (p<.0.001). 2. 증류수에 저장하였을 때, Si 용출량은 Z-350가 가장 적고, 인공 타액에 저장하였을 때, Si 용출량은 Estelite에서 가장적었다. 3. 저장용액에 따른 원소의 용출량에서 모두 유의한 평균차이를 보였다(p<.0.001) 4. 인공타액에 저장된 시편이 증류수에 저장된 시편보다 시간이 증가할수록 Ba와 Si의 용출량이 더 많았다. 5. 저장기간에 따른 필러의 용출량은 저장 용액 간, 재료 간에 유의한 상관관계를 보였다(p<.0001). 이상을 통해 나노필러를 함유한 복합레진이 수분환경에 노출되었을 때 필러 입자들의 지속적인 용출이 일어남을 확인할 수 있었다.

• 한국응용과학기술학회지
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• 제41권2호
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• pp.424-435
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• 2024

본 연구는 임상간호사의 사회적 지지, 자기효능감, 직무스트레스가 건강증진행위에 미치는 영향을 확인하기 위해 시행되었다. 연구 대상자는 G시에 소재한 3개의 종합병원에 근무 중인 6개월 이상의 임상간호사 345명으로, 수집된 자료는 SPSS 26.0 program을 이용하여 기술통계, t-test, ANOVA, Pearson 상관관계 및 다중회귀분석을 시행하였다. 연구결과, 사회적 지지(𝛽=.36, p<.001)와 자기효능감(𝛽=.35, p<.001)이 높고, 직무스트레스가(𝛽=-.09, p=.018) 낮은 경우, 주 4회 이상 아침식사(𝛽=.20, p<.001)를 하는 경우, 주관적 건강상태가 건강(𝛽=.20, p=.001)하거나 보통인 경우(𝛽=.20, p<.001) 건강증진행위 수준이 높은 것으로 나타났고, 건강증진행위에 대한 이들 변수의 설명력은 49%로 나타났다(F=26.57, p<.001). 따라서 임상간호사의 건강증진행위 향상을 위한 프로그램 및 정책반영이 필요하다.

• 임상간호연구
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• 제30권2호
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• pp.84-93
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• 2024

Purpose: The purpose of this study was to investigate the impact of nurse educators' competency on their job satisfaction. Methods: The subjects of this study were nurses in charge of nursing education at the general hospital level or higher organization. Data were collected via an online survey from May 3 to May 20, 2024, from 91 respondents. The survey questionnaires included general characteristics, competency, and job satisfaction. Descriptive statistics, Pearson's correlation coefficients, t-tests, and simple linear regression were performed using SPSS 21. Results: There was a positive correlation between nurse educators' competency and job satisfaction. Specifically, professional knowledge (r=.47, p<.001), research competency (r=.47, p<.001), task standardization competency (r=.46, p<.001), communication skills (r=.42, p<.001), and educational implementation competency (r=.42, p<.001) showed positive correlations with job satisfaction. The differences in competency based on completing the advanced nurse training course was not significant (t=-1.46, p=.149). However, competency level was found to significantly affect job satisfaction (β=.49, p<.001). Conclusion: The study highlights the need for competency-based education programs to strengthen nurse educators' qualifications systematically.

• Journal of Korean Neurosurgical Society
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• 제64권1호
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• pp.78-87
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• 2021

Objective : Intraoperative neurophysiological monitoring (IONM) has been widely used during spine surgery to reduce or prevent neurologic deficits, however, its application to the surgical management for cervical myelopathy remains controversial. This study aimed to assess the success rate of IONM in patients with cervical myelopathy and to investigate the factors associated with successful baseline monitoring and the effect of increasing the stimulation intensity by focusing on motor evoked potentials (MEPs). Methods : The data of 88 patients who underwent surgery for cervical myelopathy with IONM between January 2016 and June 2018 were retrospectively reviewed. The success rate of baseline MEP monitoring at the initial stimulation of 400 V was investigated. In unmonitorable cases, the stimulation intensity was increased to 999 V, and the success rate final MEP monitoring was reinvestigated. In addition, factors related to the success rate of baseline MEP monitoring were investigated using independent t-test, Wilcoxon rank-sum test, chi-squared test, and Fisher's exact probability test for statistical analysis. The factors included age, sex, body mass index, diabetes mellitus, smoking history, symptom duration, Torg-Pavlov ratio, space available for the cord (SAC), cord compression ratio (CCR), intramedullary increased signal intensity (SI) on magnetic resonance imaging, SI length, SI ratio, the Medical Research Council (MRC) grade, the preoperative modified Nurick grade and Japanese Orthopedic Association (JOA) score. Results : The overall success rate for reliable MEP response was 52.3% after increasing the stimulation intensity. No complications were observed to be associated with increased intensity. The factors related to the success rate of final MEP monitoring were found to be SAC (p<0.001), CCR (p<0.001), MRC grade (p<0.001), preoperative modified Nurick grade (p<0.001), and JOA score (p<0.001). The cut-off score for successful MEP monitoring was 5.67 mm for SAC, 47.33% for the CCR, 3 points for MRC grade, 2 points for the modified Nurick grade, and 12 points for the JOA score. Conclusion : Increasing the stimulation intensity could significantly improve the success rate of baseline MEP monitoring for unmonitorable cases at the initial stimulation in cervical myelopathy. In particular, the SAC, CCR, MRC grade, preoperative Nurick grade and JOA score may be considered as the more important related factors associated with the success rate of MEP monitoring. Therefore, the degree of preoperative neurological functional deficits and the presence of spinal cord compression on imaging could be used as new detailed criteria for the application of IONM in patients with cervical myelopathy.

• Current Photovoltaic Research
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• 제2권1호
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• pp.1-7
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• 2014

We developed a method of growing thin Si film at $600^{\circ}C$ by hot wire CVD using a very thin large-grained poly-Si seed layer for thin-film Si solar cells. The seed layer was prepared by crystallizing an amorphous Si film by vapor-induced crystallization using $AlCl_3$ vapor. The average grain size of the p-type epitaxial Si layer was about $20{\mu}m$ and crystallographic defects in the epitaxial layer were mainly low-angle grain boundaries and coincident-site lattice boundaries, which are special boundaries with less electrical activity. Moreover, with a decreasing in-situ boron doping time, the mis-orientation angle between grain boundaries and in-grain defects in epitaxial Si decreased. Due to fewer defects, the epitaxial Si film was high quality evidenced from Raman and TEM analysis. The highest mobility of $360cm^2/V{\cdot}s$ was achieved by decreasing the in-situ boron doping time. The performance of our preliminary thin-film solar cells with a single-side HIT structure and $CoSi_2$ back contact was poor. However, the result showed that the epitaxial Si film has considerable potential for improved performance with a reduced boron doping concentration.