• 한국산학기술학회논문지
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• 제11권8호
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• pp.2741-2749
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• 2010

본 논문은 필라멘트 와인딩 공법으로 제조된 복합재 압력용기의 충격손상 및 이에 대한 표면 보호재료의 영향을 평가한 것이다. 낙하식 충격시험기를 이용하여 기본 패널과 보호재료(고무, kevlar/epoxy 및 glass/epoxy)가 표면에 접착되어 있는 보호 패널에 대한 저속 충격시험을 실시하였다. 복합재 압력용기의 손상 저항성에 대한 표면 보호재료의 영향을 정량화하기 위하여 충격손상 파라미터를 도입하였다. 복합재 압력용기의 손상 저항성은 충격압자의 형상과 관계없이 표면 보호재료의 영향을 크게 받았으며 이러한 표면 보호재료중 glass/epoxy가 가장 큰 보호효과를 나타내었다.

• 한국재료학회지
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• 제9권6호
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• pp.556-563
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• 1999

The corrosion behavior of heat-resistant alloys, More 1 and Super 22H in molten salts of LiCl and $LiCl-Li_2$O was investigated in the temperature range of $650~850^{\circ}C$. In a molten salt of LiCl, a dense protective oxide scale of $LiCrO_2$ was formed, following growth of oxide scale with parabolic kinetics. But in a mixed molten salt of LiCl, a dense protective oxide scale of $LiCrO_2$ was formed, following growth of oxide scale with parabolic kinetics. But in a mixed molten salt of $LiCl-Li_2$O, a porous non-protective scale of Li\ulcorner(Cr, Ni, Fe)\ulcornerO$_2$was formed, following growth of oxide scale with linear kinetics. The corrosion rate increased slowly with the increase of temperature up to $750^{\circ}C$, but above $750^{\circ}C$ rapid increase in corrosion rate observed. The corrosion behavior of Super 22H alloy was similar to that of More 1 alloy, but Super 22H showed higher corrosion resistance than More 1.

• 한국콘텐츠학회논문지
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• 제21권5호
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• pp.627-637
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• 2021

우리나라는 신체적 위해 뿐만 아니라, 사회경제적으로도 규모와 심각도를 더해가고 있는 음주폐해의 감소를 위해 다양한 방안들을 모색하고 있다. 그 중에서도 개인들의 음주행태 개선은 음주폐해를 줄이는 가장 직접적인 방법이다. 외국에서는 '보호행동전략'의 사용이 음주폐해를 줄이는 효과적인 방안으로 알려져 있는데, 우리나라에서는 성인을 대상으로 이를 조사하여 검증한 연구들이 매우 부족하다. 따라서 본 연구는 보호행동전략의 사용이 음주폐해 감소에 유의한 영향을 끼치는지를 확인하고자 하였다. 전국 성인 남녀 2,000명을 대상으로 한 연구 결과, 보호행동전략의 사용은 음주폐해를 줄이는 것으로 나타났으며, 음주폐해에 가장 큰 영향을 끼친 것은 심각한 폐해감소 전략 영역이었고, 다음으로 음주방법 제한 영역이었다. 음주량 감소 영역의 영향은 유의하지 못한 것으로 나타났다. 이 외에도 음주빈도, 폭음, 음주 동기는 음주폐해에 정적인 영향을 끼쳤으며, 사교 동기의 경우만 부적인 영향을 끼쳤다. 본 연구에서는 향후 종단연구를 통한 면밀한 요인들 간의 관계 파악, 대상층을 세분화한 보호행동전략 사용 강화 방안에 관한 후속 연구들을 제안하였다.

• 한국표면공학회지
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• 제30권4호
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• pp.248-254
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• 1997

The sulfidation behavior of a sputter-deposited amorphous coating of 69.0%Nb-16.9Ni-11.9%Al-2.2%Si (at.%) has been investigated as a funtion of temperature.(973-1173K) in pure sulfur pressure of 0.01atm. The sulfidation kinetics of the casting obyed the parabolic rate low over the whole temperature ranges studied. The stlfidation rate increased with the temperature, as expected. The sulfide scale, the composition of which was $Al_2S_3,\;NbS_2,\;Ni_{3-x}S_2\;and\;FeCrS_4$, formed on the amorphous coating was primarily bilayered. Both the outer fastgrowing non-protective 4Al_2S_3$scale and the inner slowly-growing protective $NbS_2$,/TEX> scale and the inner slowly-growing protective $NbS_2$ scale had some Fe and Cr dissolution, which evidently came from the base substrate alloy of stainless steel type 304. Belows the coating, Kirkendall void formation was noticed. Nevertheless, a dramatic improvement of sulfidation resistance was achieved by sputter-depositing Nb-2 Ni-Al-Si layer on the stainless steel 304.

• Tribology and Lubricants
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• 제33권6호
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• pp.275-281
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• 2017

In this work, we have fabricated anodic aluminum oxide (AAO) with ordered nanoscale porosity through an anodization process. We deposited gold and nano-organic thin films on the porous AAO surface to protect its structure and reduce friction. We investigated the tribological characteristics of the porous AAO with respect to the protective surface coatings using tribometers. While investigating the frictional characteristics of the samples by applying normal forces of the order of micro-Newton, we observed that AAO without a protective coating exhibits the highest friction coefficient. In the presence of protective surface coatings, the friction coefficient decreases significantly. We applied normal forces of the order of milli-Newton during the tribotests to investigate the wear characteristics of AAO, and observed that AAO without protective surface coatings experiences severe damage due to the brittle nature of the oxide layer. We observed the presence of several pieces of fractured particles in the wear track; these fractured particles lead to an increase in the friction. However, by using surface coatings such as gold thin films and nano-organic thin films, we confirmed that the thin films with nanoscale thickness protect the AAO surface without exhibiting significant wear tracks and maintain a stable friction coefficient for the duration of the tribotests.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2007년도 춘계학술논문 발표대회
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• pp.141-145
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• 2007

The part in the structure that is most affected by changes of external temperature is the protective concrete layer that protects a waterproofing layer. Also, the waterproofing layer that is situated under or on the back of such a protective concrete layer is affected by temperature and the behavior of the protective concrete layer under the condition of consolidation or close adhesion. In particular, in many cases, the damage is serious mainly around the projection (such as a parapet), crack, and joint (expansion joint). However, there is no proper way of examining again the non-exposed waterproofing layer once it has been constructed. Therefore, there is an assessment only on the physical property of materials and the capability of the layer in construction, and there is no actual assessment in consideration of its environmental condition or the condition of the use of buildings after construction. Therefore, in order to create more pleasant buildings and to enhance the durability of structures, this study conducts research into the change of capability of non-exposed waterproofing material after the application of a static load and moving load on the waterproofing layer situated under or on the back of protective concrete.

• 지역사회간호학회지
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• 제12권2호
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• pp.406-416
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• 2001

This study is performed to confirm the influencing factors of family health protection behaviors using the variables included in Pender's Family Promotion Model. 1. The subjects are 110 families in preschooler family developmental stage, respondents are children's mother or father. These families are almost all nuclear types(95%), function of families is healthy as much as 8.0 the mean FAPGAR score. The prevalence rate of family members' illness was 14.7% these last 3 months, and 21.1 % of families responded suffered from injury for last 2 years. 2. The practice rate of injury prevention behavior is below a half in supervision and modifying of their home and residential environments, especially controlling through collaborative community power. The more familiar function score is the better practicing rates of injury prevention behaviors. 3. The injury prevention behaviors correlate to family size, health status of family member, and children's congenital defects with statistical significance. Families' economic condition correlates also significantly to family health status, cognition of benefits of injury prevention, cognition of the importance of community collecting power. And the recognition of the benefits of injury prevention correlates the adaptive health concept, family norms about injury prevention, economic status. 4. Considering family health promotion model. the general influencing factor is only affected to family protective behavior, and other paths don't affect to family's behaviors. In simple regression, the family protective behavior model explains 27.8%(P=0.05), significant factors are family function status, family size, chronic illness of family members', mother's education level. father's age. 5. To define of familiar preventive behavior as a unit is very important, but it has the limitation to solve the difficulties of family studies going with the operationalized difficulties of health promotion concept.

• 대한예방의학회:학술대회논문집
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• 대한예방의학회 1999년도 제51차 추계 학술대회 연제집
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• pp.173-174
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• 1999

• 한국의류학회지
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• 제44권3호
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• pp.516-538
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• 2020

The present study investigated regional and sex differences in knowledge, perception, cognition and behavior of fine-dust protective masks for periods of high concentration of fine dust in Korea. A total of 2,012 adults from seven provinces responded to the questionnaire. The results (all p<.05) showed that 78% of respondents considered pollution from China to be the greatest contributor of fine dust. Seoul and Gyeonggi residents more frequently checked fine dust forecasts than other provinces and consulted their smartphone applications to do so more than other residents. Jeju, Gwangwon, and Jeonla residents had less knowledge of KF 80, 94, and 99 masks than residents of other provinces. Gwangwon and Jeju residents had less trust in the effectiveness of protective masks than other residents. Females perceived themselves as unhealthier respiratory, more frequently checked the concentration of fine dust, trusted more the effectiveness of masks, and more frequently wore masks, compared to male respondents. Those who self-identified their respiratory function as poor, more frequently checked fine dust forecasting, and had greater knowledge of masks, which resulted in greater trust in the protective function of masks, and finally had higher wear frequency of masks for days with high concentrations of fine dust.

• 지역사회간호학회지
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• 제27권2호
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• pp.106-113
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• 2016

Purpose: The purpose of this study was to determine the relationship between unhealthy eating behavior and depression in adolescents, with confounding variables adjusted. Methods: This study is a secondary analysis of the data collected from the 2013 Korean Youth Risk Behavior Web-based Survey (KYRBWS). The analysis included 72,435 participants (36,655 male and 35,780 female). The data were analyzed by $x^2$ test, t-test, and logistic regression analysis using SPSS Version 21 by complex samples analysis. Results: Compared with male adolescents with healthy eating behavior, those who with unhealthy eating behavior were more likely to suffer depression with other factors controlled (OR=1.37, 1.07~1.75). On the other hand, female adolescents with unhealthy eating behavior were less likely to feel depressed compared with female adolescents with unhealthy eating behavior and with other factors controlled (OR=0.98, 0.64~1.50). However, it was not statistically significant. Conclusion: Our findings suggest that healthy eating behavior may be a protective factor against depression in male adolescents, but not in female adolescents. Furthermore, our results suggest that the longitudinal associations between mental health and healthy eating behavior and other lifestyle factors are complex.