• Transactions of the Korean hydrogen and new energy society
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• v.26 no.5
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• pp.423-430
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• 2015

$Cu/ZnO/Al_2O_3$ catalysts for water gas shift (WGS) reaction were synthesized by co-precipitation method with the fixed molar ratio of Cu/Zn/Al precursors as 45/45/10. Copper and zinc precursor were added into sodium carbonate solution for precipitation and aged for 24h. During the aging period, aluminum precursor was added into the aging solution with different time gap from the precipitation starting point: 6h, 12h, and 18h. The resulting catalysts were characterized with SEM, XRD, BET surface measurement, $N_2O$ chemisorption, TPR, and $NH_3$-TPD analysis. The catalytic activity tests were carried out at a GHSV of $27,986h^{-1}$ and a temperature range of 200 to $400^{\circ}C$. The catalyst morphology and crystalline structures were not affected by aluminum precursor addition time. The Cu dispersion degree, surface area, and pore diameter depended on the aging time of Cu-Zn precipitate without the presence of $Al_2O_3$ precursor. Also, the interaction between the active substance and $Al_2O_3$ became more stronger as aging duration, with Al precursor presented in the solution, increased. Therefore, it was confirmed that aluminum precursor addition time affected the catalytic characteristics and their catalytic activities.

• 한국노년학
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• v.41 no.1
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• pp.49-68
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• 2021

The present study aims to examine the mediating role of life satisfaction in the relationship between productive activities and future time perspective in later life. Drawn from the 7^th wave of the Korea Longitudinal Study of Aging, our sample consists of a total of 6,756 older adults aged 55 and over. Complex samples analyses were conducted the relationship between productive activities, life satisfaction and future time perspective measured in two dimensions (i. e., life expectancy and job expectation). Results from complex samples analysis showed that productive activities were associated with life satisfaction and future time perspective. Employed older adults including unpaid family workers tended to have higher levels of life satisfaction and future time perspective (i.e., life expectancy and job expectation) than their counterparts. The relationship between productive activities and future time perspective was mediated by life satisfaction. Findings suggest that engaging in productive activities influences better satisfaction with life among older adults, which is eventually linked to an expansive view of the future. Policy implications were discussed that promoting productive activities in later life and age-friendly working environment should be encouraged.

• 한국노년학
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• v.39 no.4
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• pp.825-846
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• 2019

This study aims to identify subgroups of ageism among young adults of age 20-39, and to examine its relationship to perceptions of generational conflict and elderly welfare policy. Latent Profile Analysis(LPA) was applied on the data 'Survey on Age Integration and Generational Integration', which was executed by institute for Age Integration Researchof Ewha Womans university, and descriptive statistics and cross-tabulation analysis were performed to examine the socio-demographic characteristics of each subgroup. Then, regression analysis was performed to observe the effect of the subgroups on the perceptions of generational conflict and elderly welfare policy. The results are as follows. The resulting subgroups of ageism among young adults were 'compound perception on aging and active age discrimination', 'medium-level aging anxiety and passive age discrimination', and 'low-level aging anxiety and beyond age discrimination'. Subgroups of ageism affected both perceptions of generational conflict and elderly welfare policy, whereas social support only affected perception of elderly welfare policy. Based on the results, political implications, such as activation of education on perception on aging, expansion of generational exchange for age integration, and renewal of social atmosphere for intergenerational coexistence, which will promote social integration

• Korean Journal of Culture and Social Issue
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• v.26 no.2
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• pp.47-68
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• 2020

Since the early 2000s, Korea has continued to increase the proportion of the elderly population due to low fertility and increased life expectancy. As a result, Korea has now entered the aging society. Because of this demographic change, proportion of active elderly have increased, and many academics, such as sociology, economics, and psychology, have conducted various studies on the active elderly. This study focused on active elderly based on the activity theory of old age and the positive effect of small community participation activity on the elderly. The purpose of this study is to examine whether active elderly' participation in everyday activities, small community participation of the elderly affect citizen participation actively in society as a citizen, and in the process, mediates the effect of small community cohesion and the moderating effect of small community selfishness. This study performed a stepwise regression analysis and a hierarchical regression analysis of 700 elderly people who are participated actively in various small communities. As a result, the partial mediating effect of small community cohesion was shown in the relationship between participation in everyday activities and citizen participation, and the moderating effect of small community selfishness was also shown. These findings suggest that government and interested parties need to develop and implement policies for the small community participation of elderly citizens in consideration of their small community activities, small community cohesion and small community egoism.

• Journal of the Korean Applied Science and Technology
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• v.32 no.2
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• pp.312-319
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• 2015

In this study, n-butanol and ethyl acetate extracts were prepared from raw yam (Dioscorea batatas DECNE.). Their antioxidative potencies were investigated employing various in vitro methods, such as ferrous ion chelating, ${\beta}$-carotene bleaching assay, lipid peroxidation inhibition and nitric oxide (NO) radical scavenging and nitrite scavenging activity. The n-butanol fraction was assayed to possess stronger antioxidant activity by ${\beta}$-carotene bleaching assay, lipid peroxidation inhibition and NO radical scavenging activity. However, ethyl acetate extract was more effective in chelating ferrous ion and scavenging nitrite. Based on the results obtained, yam is a potential active ingredient that could be applied in antioxidation as well as bio-health functional food to take a good part in prevention of human diseases and aging.

• Journal of Environmental Science International
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• v.27 no.10
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• pp.853-863
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• 2018

In order to increase the medicinal herbs efficiency of drug delivery, vesicles contained with medicinal herbs were prepared by phosphatidylcholines and surface active agent. Vesicles loaded with medicinal herbs were characterized by UV-spectroscopy, Zetasizer. The antioxidant activity of vesicles was measured by DPPH assay and ABTS radical scavenging assays. Also, an analysis was conducted to determine the effects of anti-inflammatory of vesicles contained medicinal herbs. In addition, the whitening effects of vesicles contained medicinal herbs extract were studied via tyrosinase inhibition assay. The results of vesicles were as follows. Vesicles appeared an average diameter of approximatively 164-599 nm. All studied vesicles contained with medicinal herbs showed antioxidant, anti-inflammatory and whitening effects in a dose-dependent manner. Therefore, this experiment achieves its purpose of synthesizing of vesicles. In conclusion, we recommended that the vesicles loaded with medicinal herbs have ability for anti-aging materials. Specifically, it will apply to cosmetic ingredients.

• Proceeding of Spring/Autumn Annual Conference of KHA
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• 2009.11a
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• pp.229-234
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• 2009

Korea's aging population is increasing rapidly every year. In addition, because of the increase in quantity of apartment complexes, the number of elderly living in apartment complexes is also rising steadily. Consequently, caring about the elderly residents is getting more important in apartment complexes. Currently the most common recreational facility for senior in the apartment complex is 'Kyungrodang'. However, 'Kyungrodang' has not been used as an active community area to elderly residents due to lack of leisure programs and other services. The purpose of this study was to give direction to support leisure life and healthy living for senior residents and to make 'Kyungrodang' usable community space for the residents of all generations. In connection with this, this study also identified to find ways to revitalizing for 'Kyungrodang'. The result of the study suggested the ideas than can improve the usably of 'Kyungrodang' not only to the elderly residents but also to all residents in terms of space planning and leisure programs.

• International Journal of Automotive Technology
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• v.8 no.4
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• pp.445-453
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• 2007

This paper presents a robust controller design approach for improving vehicle dynamic roll motion performance and guaranteeing the closed-loop system stability in spite of vehicle parameter variations resulting from aging elements, loading patterns, and driving conditions, etc. The designed controller is linear parameter-varying (LPV) in terms of the time-varying parameters; its control objective is to minimise the $H_{\infty}$ performance from the steering input to the roll angle while satisfying the closed-loop pole placement constraint such that the optimal dynamic roll motion performance is achieved and robust stability is guaranteed. The sufficient conditions for designing such a controller are given as a finite number of linear matrix inequalities (LMIs). Numerical simulation using the three-degree-of-freedom (3-DOF) yaw-roll vehicle model is presented. It shows that the designed controller can effectively improve the vehicle dynamic roll angle response during J-turn or fishhook maneuver when the vehicle's forward velocity and the roll stiffness are varied significantly.

• Journal of Korean Public Health Nursing
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• v.25 no.1
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• pp.28-37
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• 2011

Purpose: The study examined influencing factors on death anxiety in the aged. Method: This was a descriptive survey study. Data were collected from March to June, 2010, from357 older home-dwelling adults. The questionnaires solicited information on death anxiety, family function, morale, health behavior and ego-integrity. Data was analyzed using descriptive statistics, Pearson's correlation, and stepwise multiple regression. Results: Average scores were 2.50 for death anxiety, 3.80 for family function, 9.0 for morale, 3.12 for health behavior and 2.84 for ego-integrity. There were statistically significant negative correlations between family function and death anxiety, morale and death anxiety, health behavior and death anxiety, and ego-integrity and death anxiety Morale, ego-integrity, and economic status were a significant predictor of death anxiety. Conclusion: Multilateral efforts are needed to assist the aged in successful aging through continuous body activities and active participation in society.

• The Korean Journal of Community Living Science
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• v.24 no.3
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• pp.343-354
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• 2013

Elderly people living in poverty are one of the most vulnerable population groups who are at risk of experiencing social exclusion. Social participation is an important contributing factor to active aging and social integration of the older adults living in poverty. This study aims to identify factors affecting social participation of the poor elderly. Data from the second wave of the Korean Longitudinal Study of Ageing was used for the analyses and 1,346 poor elderly aged over 65 were analyzed. The findings showed that age, education, health status, a level of depression, financial stress, and economic activity were associated with the social participation of the elderly living in poverty. These results indicated that psychological empowerment and specific needs of the older adults living in poverty should be considered in developing services and programs to promote social participation of the poor elderly.