• Bulletin of the Korean Chemical Society
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• 제31권9호
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• pp.2613-2617
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• 2010

Chloroprene is a chlorine substituent of 1,3-butadiene. Butadiene rubber (BR) and chloroprene rubber (CR) composites were thermally aged at 60, 70, 80, and $90^{\circ}C$ for 2 - 185 days in a convection oven and changes of the crosslink densities by the accelerated thermal aging were investigated. The crosslink densities increased as the aging time elapsed and as the aging temperature became higher. Degrees of the crosslink density changes of the BR composite were on the whole larger than those of the CR one except the short-term thermal aging at 60 and $70^{\circ}C$. The crosslink densities abnormally increased after themal aging at high temperatures for a long time. Activation energies for the crosslink density changes of the rubber composites tended to increase with increase of the aging time and the variation showed a local minimum. The activation energies of the CR composite were lower than those of the BR one. The experimental results were explained with a role of ligand of chlorine atom of CR in a zinc complex, steric hindrance by chlorine atom of CR, and oxidation of rubber chain.

• 한국축산식품학회지
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• 제37권6호
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• pp.823-832
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• 2017

The objective of this study was to determine the effect of aging method (dry or wet) and time (20 d or 40 d) on physical, chemical, and sensory properties of two different muscles (top round and shank) from steers (n=12) using an electronic tongue (ET). Moisture content was not affected by muscle types and aging method (p>0.05). Shear force of dry aged beef was significantly decreased compared to that of wet aged beef. Most fatty acids of dry aged beef were significantly lower than those of wet aged beef. Dry aged shank muscles had more abundant free amino acids than top round muscles. Dry-aging process enhanced tastes such as umami and saltiness compared to wet-aging process according to ET results. Dry-aging process could enhance the instrumental tenderness and umami taste of beef. In addition, the taste of shank muscle was more affected by dry-aging process than that of round muscle.

• 자원ㆍ환경경제연구
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• 제21권2호
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• pp.341-369
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• 2012

국내의 심각한 저출산 문제와 평균수명의 연장으로 인하여 고령화가 다른 어떤 나라들보다도 빠르게 진행되고 있기 때문에 고령화 문제를 심각하게 다루고 다양한 사회적 파급효과를 분석하여 대응할 필요가 있다. 따라서 본 연구에서는 고령화가 가정용 전력수요에 미치는 영향을 분석하였다. 1965년~2010년까지 46년간의 연도별 시계열 자료를 분석한 연구 결과에 의하면 가정용 전력수요는 전력가격, 소득 수준, 고령화에 유의하게 반응하고 있는 것으로 분석되었고, 특히 고령화가 가정용 전력수요에 미치는 영향은 단기적으로 더욱 크게 나타났다. 이러한 결과는 고령화가 전력수요에 복합적인 영향을 미치는데 단기적으로 수요를 감소시키는 요인이 더욱 강력하게 영향을 주는 반면, 수요를 증가시키는 요인은 장기적으로 서서히 나타나기 때문일 것이다. 그러나 장기적으로도 고령화는 가정용 전력수요를 감소시키는 것으로 나타났고, 정부가 예측한 속도로 고령화가 진행될 경우 가정용 전력수요는 연간 3%보다 낮은 수준으로 증가할 것으로 예상된다.

• 근관절건강학회지
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• 제26권3호
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• pp.175-183
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• 2019

Purpose: This is a descriptive research examining the relationships between aging anxiety, perceived level of successful aging, and preparation for aging as well as factors influencing preparation for aging. Methods: Subjects of this study were 221 women aged between 40 and 59 years residing in area J. Data were collected from October 27, 2017 to November 9, 2017, using a structured questionnaire. The collected data were analyzed using the statistical program SPSS/WIN 24.0. Results: Regression analysis revaled that factors having a significant effect on the preparation for aging of the subjects were age, perceived health status, exercise, leisure activity, aging anxiety, and perception of successful aging. The total explanatory power was 42.3%. Conclusion: Based on the results of this study, it was found that aging anxiety and successful aging influenced the preparation for aging of middle-aged women. Therefore, it is necessary to develop a nursing intervention that properly manage aging anxiety and improves successful aging, in order to encourage middle-aged women to actively prepare for their later lives.

• 한국노년학
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• 제41권4호
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• pp.527-546
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• 2021

본 연구는 노인의 과거수용이 자살생각에 영향을 미치는 경로에서 노화태도와 우울의 이중매개효과를 검증하는데 목적이 있다. 서울 및 경기도 지역 노인복지관을 이용하는 65세 이상 노인을 대상으로 2017년 2월부터 8월까지 대면 설문조사를 진행하였으며, 최종적으로 329명의 자료를 분석에 활용하였다. 분석 방법으로는 SPSS PROCESS macro 프로그램을 활용하여 매개변수가 2개인 직렬다 중매개모형 검증을 통해 이중매개효과를 확인하였으며, 부트스트랩을 활용하여 매개효과의 유의성을 검증하였다. 본 연구의 주요 결과는 다음과 같다. 첫째, 노인의 과거수용은 노화태도에, 노화태도는 우울에, 우울은 자살생각에 각각 유의한 영향을 미치는 것으로 나타났으나, 노인의 과거수용이 자살생각에 미치는 직접 효과는 유의하지 않았다. 둘째, 노인의 과거수용과 자살생각의 관계에서 노화태도와 우울을 순차적으로 경유하여 자살생각에 이르는 경로만이 유의한 것으로 나타나 이중매개효과가 확인되었다. 이러한 결과를 바탕으로 노인의 우울 감소와 자살 예방을 위한 긍정적인 과거수용과 노화태도 증진 방안을 정책적·실천적 측면에서 제시하였다.

• 한국재료학회지
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• 제24권11호
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• pp.610-616
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• 2014

In this study, we investigated the precipitation behavior of the R-phase precipitated at the initial stage of aging and its effect on the pitting corrosion of 25%Cr-7%Ni-4%Mo super duplex stainless steel. The R-phase in super duplex stainless steel was mainly precipitated at the interface of ferrite/austenite phases and inside of the ferrite phase during the initial stage of aging, and it was transformed into the ${\sigma}$-phase with an increase in aging time. The ferrite phase was decomposed into a new austenite phase and ${\sigma}$-phase. The R phase was an intermetallic compound, which represented a lower Ni and higher Mo than the matrix, and also had a higher Mo and Cr concentration than the ${\sigma}$ phase. With an increasing aging time, the pitting potential $E_p$ was increased slowly by the precipitation of the R-phase, and it was then steeply decreased by the precipitation of the ${\sigma}$-phase. The R-phase was decreased the pitting potential, but its effect was smaller than effect of ${\sigma}$-phase.

• 대한화장품학회:학술대회논문집
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• 대한화장품학회 2003년도 IFSCC Conference Proceeding Book I
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• pp.291-312
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• 2003

Reactive oxygen species are capable of damaging biomolecules such as lipids, proteins, and DNA, which can not only lead to various diseases, but also oxidative damage resulting aging. In our previous study, Cercis chinensis (Leguminosae) showed a potent antioxidant activity. Nineteen compounds were isolated through antioxidant activity-guided fractionation. The C. chinensis extract and some of the constituents exhibited a potent antioxidant activity on the free radicals and lipid peroxidation and a notable protective effect on the t-BuOOH induced oxidative damage. In vivo test of skin damage induced by UVB irradiation, the extract of C. chinensis and a constituent, piceatannol, exhibited a significant protective effect. The life-span of the HEK-N/F cells were extended by 1.21-2.12 fold as a result of the continuous administration of 3 $\mu\textrm{g}$/ml of the C. chinensis extract and the active constituents compared to that of the control. These observations were attributed to the inhibitory effect of the C. chinensis extract and its constituents on the age-dependent shortening of the telomere. Thus, C. chinensis was demonstrated to protect the skin cells against oxidative stress and inhibit thereby the cellular aging, followed by expectation as anti-aging cosmetic ingredient.

• 한국연초학회지
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• 제26권1호
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• pp.35-42
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• 2004

This study was carried out to examinate the effect of aging period on chromatic, chemical and organoleptic characteristics, and to evaluate of optimum aging period for each grade in burley leaf tobacco. The leaf tobaccos were produced in 2000, and threshed, redried and packed in carton box under the current methods. Four grades of processed leaf(A3T, B1T, C1W and D3W) were stored during 24 months (May 10, 2001 to April 31, 2003) in warehouse of Chungju Leaf Tobacco Processing Factory. The leaf tobaccos were sampled at three month intervals for analysis of chromatic, chemical and organoleptic properties. pH values of four grades, and Yellow(b) of A3T and BIT were also significantly decreased during the aging. Filling values, tar, nicotine and CO contents of tobacco smoke, and puff number of cigarettes were not significantly changed during the aging. Positive correlation coefficients were significantly observed between irritation of the calculated attributes from contents of volatile oil components in leaf tobacco and that of the panel sensory attributes. The ratio of maximum change in irritation attribute was larger than that in taste attribute during aging. The calculated irritations of 18～24 months aging for A3T and B1T were significantly lower than zero-aging, while those of C1W and D3W were not significant among aging periods. The panel irritations of 12～15 months aging for four grades were low tendency. The results suggest that decrease of aging period for thin leaf from 21～24 to 12～15 months may be beneficial to save storage cost in burley tobacco.

• 수산해양기술연구
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• 제20권1호
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• pp.23-29
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• 1984

고역알루미늄합금의 파괴특성에 미치는 시효열처리의 영향에 대하여 검토한 결과는 다음과 같다. 1. 현미경 조직의 관찰결과 $190^{\circ}C,$ 12hr로 시효열처리한 것이 시효강화된 양호한 조직과 미세한 석출분포를 나타내고 있음을 알 수 있었다. 2. 계단식시효열처리에 의하여 정상시효열처리보다 시효시간을 반정도로 단축시킬 수 있었고, 이들 조직도 유사하였다. 3. 인장파단면의 SEM 전자현미경 사진관찰결과는 $190^{\circ}C,$ 12hr으로 시효열처리한 것은 딤플형 입계 및 입내연성파괴를 나타내나, 이를 제외한 대부분은 시효열처리 시간과 온도에는 관계없이 입계연성파괴인 것이 관찰되었다.

• 가정∙방문간호학회지
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• 제23권2호
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• pp.177-185
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• 2016

Purpose: In this study, we sought to identify the impact of aging anxiety and successful aging on the personality traits of elderly. Method: Subjects were 108 elderly persons aged more than 65 years. Data collected from June to November 2015 were analyzed using descriptive statistics, t-tests, ANOVA, Pearson's correlation coefficients, and stepwise multiple regression. Results: With regard to the mean scores of personality traits, conscientiousness yielded the highest score, and neuroticism the lowest. The mean score on aging anxiety was below average, and that on successful aging was above average. Aging anxiety differed significantly according to age, present job, economic status, and health status. Successful aging differed significantly according to having a spouse, economic status, and health status. Significant correlations were found between anxiety and conscientiousness, extraversion, and neuroticism, and between successful aging and conscientiousness, agreeableness, extraversion, openness, and neuroticism. Conscientiousness and neuroticism had an effect on aging anxiety (23.2%), whereas conscientiousness, agreeableness, extraversion, openness, and neuroticism affected aging anxiety (45.3%). Conclusion: These findings indicate that personality traits reduce aging anxiety and lead to successful aging among elderly.