• Transactions of the Korean Society of Mechanical Engineers A
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• v.27 no.8
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• pp.1398-1408
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• 2003

Tensile and LCF(low cycle fatigue) tests were carried out in air at wide temperature range 20$^{\circ}C$-750$^{\circ}C$ and strain rates of 1${\times}$10$\^$-4//s-1${\times}$10$\^$-2/ to ascertain the influence of strain rate on tensile and LCF properties of prior cold worked 316L stainless steel, especially focused on the DSA(dynamic strain aging) regime. Dynamic strain aging induced the change of tensile properties such as strength and ductility in the temperature region 250$^{\circ}C$-600$^{\circ}C$ and this temperature region well coincided with the negative strain rate sensitivity regime. Cyclic stress response at all test conditions was characterized by the initial hardening during a few cycles, followed by gradual softening until final failure. Temperature and strain rate dependence on cyclic softening behavior appears to result from the change of the cyclic plastic deformation mechanism and DSA effect. The DSA regimes between tensile and LCF loading conditions in terms of the negative strain rate sensitivity were well consistent with each other. The drastic reduction in fatigue resistance at elevated temperature was observed, and it was attributed to the effects of oxidation, creep and dynamic strain aging or interactions among them. Especially, in the DSA regime, dynamic strain aging accelerated the reduction of fatigue resistance by enhancing crack initiation and propagation.

• Journal of agricultural medicine and community health
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• v.46 no.2
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• pp.89-97
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• 2021

Objectives: The purpose of this study is to identify the relationship among psychosocial stress, memory, and successful aging of the community-residing elderly. Methods: 152 people over 65 years old living in D area were interviewed, from August 1st, 2020 to October 30th, 2020. The outcomes were measured by Psychosocial Well-being Index (PWI), Mini-Memory Test (MiMeT) and successful aging. Data were analyzed using Pearson correlation coefficients and stepwise multiple regression. Results: There was a positive correlation between successful aging and memory. There was a negative correlation between psychosocial stress and successful aging, and between psychosocial stress and memory. Psychosocial stress was identified as a predictor of successful aging, which explained 26.4% of total variance of successful aging. Conclusions: When we prepare intervention programs which improve successful aging for community-residing older adults, we need to consider psychosocial stress. In addition, stress management programs for successful aging should be developed to improve current successful aging.

• International Journal of Advanced Culture Technology
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• v.6 no.3
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• pp.59-68
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• 2018

This study was a cross-sectional descriptive study of the effects of emotional happiness on aging preparation for 45-60 year olds. Participants of this study were 312 volunteers and data was collected online, the collection period was from May 15, 2018 to May 31, 2018. The tools used in the research were the emotional happiness developed by Watson et al (1988) et al., the aging preparation developed by JH Lee (2009). Analysis was done using t-test, ANOVA, Pearson correlation, and regression by SPSS 18.0. As a result of the analysis, 84.0% of participants felt physically healthy and 89.8% felt mental health. The spouses of participants were physically 83.4% healthy and mentally 82.7% healthy. The correlation between emotional happiness, health cognition and aging preparation showed that physical health had a correlation with mental health (r = .482, p <0.01) and emotional happiness (r = .369, p <0.01), economic aging preparation (r = .411, p <0.01), social aging preparation (r = .119, p <0.01). Mental health was correlated with emotional happiness (r = .491, p <0.01), economic aging preparation (r = .411, p <0.01) and social aging preparation. Difference between emotional happiness and retirement preparation according to presence or absence of disease, emotional happiness (t = -4.503, p <0.01) and economic aging preparation (t = -4.960, p <0.01) were statistically significant. Emotional happiness affects the preparation of old age, emotional happiness affects to physical aging preparation under statistical significance (F=25.191, p<0.01), economic aging preparation (F=1131.783, p<0.01), and social aging preparation (F=147.672, p<0.01) which were sub components of aging preparation. Emotional happiness showed a 7.5% effect on the preparation of physical aging, 78.4% on economic aging preparation and 32.3% on social aging preparation. Based on the above results, it can be concluded that physical health and mental health are related to emotional happiness, economic aging preparation, and social aging preparation. And also these results can be inferred that the illness causes emotional less feeling of happiness and economic difficulty. Based on the results of this study, emotional well - being influences the retirement preparation significantly at statistical significance. Therefore, if the concept of emotional happiness is introduced to the old-age preparation program, it will be more client centered program.

• Journal of The Korea Institute of Healthcare Architecture
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• v.13 no.1
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• pp.27-35
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• 2007

According to the 2005 Korean census, the 65 and over population now exceeds 9.5% of the total population and is growing rapidly. Meeting elderly environment and care needs of this rapidly growing segment of the population becomes a major challenge for public policies and planners. Since great deal amount of elderly will reside in their houses, aging in place concept becomes important. For the success of aging in place, the quality of individual house unit, community support systems, and quality of senior center of the community are crucial. Since elderly environments and facilities serve not only medical and/or care programs but also social activity program in aging society, senior centers need to promote social activities and other care programs. The purpose of this study is to analyze characteristics of environmental affordance of a well received senior center in Tokyo, Japan. In order to analyze the characteristics, Murtha & Lee user benefit criteria and Lawton's environmental affordance approaches were used. As results, design characteristics and interior elements which provide environmental affordance were enumerated by type of space. Based on needs and user benefit criteria, those features were analyzed. This study shows design characteristics, elements, and attributes which are well received and utilized by elderly users.

• Korean journal of communication and information
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• v.61
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• pp.159-179
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• 2013

This study aims to consider the criteria and signification of 'aging' constructed in media in Korean society that has entered aging society. For the purpose, this study analyzed KBS the representative TV health programs. According to the result, designs the measurable indexes of aging to rank the casts. And it emphasizes to the casts that cannot reach a certain level the support from medical experts or advanced medical technology. With such characteristics of individual text, this paper found the ideological codes of the health programs. They contrast the elderly who have achieved successful aging from those that have not. They define the aged who have not practiced self-management or medical control to prevent aging properly as failure and also make fun of them. They draw aging that was not regarded as some kind of disease in the past into the area of medicine. Besides, the medicalization of aging regarded as an object for treatment may come to strengthen the control of medical experts and also individualize social issues.

• Journal of Electrical Engineering and Technology
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• v.10 no.3
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• pp.1114-1123
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• 2015

Bushing is the key link to connect outer and inner insulating systems and also the essential electric accessory in electric power system, especially in the high voltage engineering (AC 1000kV, DC 800kV). This paper presented the experimental research of thermal aging characteristic of oil-paper insulation used in bushing. A thermally accelerated aging experiment at 90℃ was performed. The bushing models containing five layers of paper were sealed into the aging vessels and further aged for 250 days. Then several important parameters associated with the aging were observed and evaluated. The results showed that the degree of polymerization (DP) of papers gradually decreased. The DP values of outermost layer and middle layer fit well into the second-order kinematic model and first-order kinematic model, respectively. Less deterioration speed of the inter-layer paper than outer layer was confirmed by the variation of DP. Hydrolysis was considered as the main cause to this phenomenon. In addition, the logarithm of the furfural concentrations in insulation oil was found to have good linear relationship with DP of papers. Interestingly, when the aging time is about 250 days and DP is 419, the aging process reaches an inflection point at which the DP approaches the leveling off degree of polymerization (LODP) value. Both tanδ and acid number of oils increased, while surface and volume resistivity of papers decreased. The obtained results demonstrated that thermal aging and moisture absorbed in papers brought great influence to the degradation of insulating paper, leading to rapid decrease of DP and increase of the tanδ. Thus, the bushing should be avoided from damp and real-time monitoring to the variation of tanδ and DP values of paper is an effective way to evaluate the insulation status of bushing.

• Journal of Pharmacopuncture
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• v.20 no.1
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• pp.29-35
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• 2017

Objectives: Aging is an unconscious and gradual process that can lead to changes in biological systems. Induction of oxidative stress and apoptosis, hepatotoxicity and neurotoxicity are involved in the aging process. Regarding the antioxidant property of black seed oil, the aim of this study was to evaluate the anti-aging effect of Nigella sativa (N. sativa) oil on d-galactose-induced aging in mice. Methods: For induction of aging, D-galactose (500 mg/kg, subcoutaneously SC) was administrated to male mice for 42 days. Animals were treated with D-galactose alone or with b lack seed oil (0.1, 0.2, 0.5 mL/kg, intraperitoneally (ip)). Additionally, vitamin E (200 mg/kg) was used as a positive control. At the end of treatment, the malondialdehyde (MDA) and the glutathione (GSH) contents in brain and liver tissues were measured. Also, enzymes in serum, including aspartate aminotransferase (AST) and alanine amino transferase (ALT), were determined. The levels of the proteins Bax, Bcl2, caspase-3 (pro and cleaved) in brain and liver tissues were evaluated. Results: Administration of D-galactose (500 mg/kg, SC) for 42 days increased serum levels of ALT and AST, as well as the MDA content, in brain and liver tissues, but decreased the GSH content. Additionally, the levels of apoptotic proteins, including Bax, procaspase-3 and caspase-3 cleaved, were markedly increased. N. sativa oil (0.1 and 0.2 mL/kg) diminished the levels of the biochemical markers ALT and AST. Administration of black seed oil (0.1, 0.2 and 0.5 mL/kg) reduced lipid peroxidation and at doses 0.1 and 0.2 mL/kg significantly recovered the GSH content. The oil decreased Bax/Bcl2 levels and at 0.1 mL/kg down-regulated the expressions of caspase-3 (pro and cleaved) proteins in brain and liver tissues. Conclusion: Through its antioxidant and anti-apoptosis properties, black seed oil exhibited an anti-aging effect in a model of aging induced with D-galactose.

• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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• 2002.10b
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• pp.371-372
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• 2002

It is well known that red blood cells (RBCs) are suffered from chronic stresses in systemic circulation. The objective of this study is to clarify the effect of the aging of RBCs on rheological properties and hemolysis. Initially, RBCs age fractionation was performed by using a high-speed centrifugation (15[min] at 1500[G]), then young and aged RBCs were suspended in plasma to adjust the hematocrit level of 40[%]. After this pretreatment, the viscosity was measured by using a capillary type and a cone-plate type viscometers, respectively, and the hemolysis test was carried out by a seesaw type shaker. Results from these experiments showed that the viscosity of the aged RBCs measured by the capillary viscometer was increased by 10[%] as compared with that of the young RBCs. Under the condition of all shear zones, the viscosity of the aged RBCs was increased in case of using the cone-plate type viscometer. And the hemolytic level was increased twice as the aging. The data obtained in this study indicated that the ability of aggregation of RBCs was increased and the deformability of RBCs membrane got lower with the aging. Furthermore, it was exhibited that the fragility of RBCs ’ membrane was increased with the aging.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.11 no.11
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• pp.1035-1042
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• 1998

After the 1990's, a computer-aided partial discharge(PD) measurement system was referred in part of aging diagnosis using digital signal processing as the new technology has been studied. The PD patterns and relevant information for pattern recognition are discussed in PD research area, because discharge quantity(q), the number of discharge pulse(n) and the applied boltage phase($\varphi$) was combined with the system information of the aging state. This paper investigates the discharge phase and quantity, as well as the number of discharge(n) with regard to discharge signals generated in power cable. therefore, according to characteristic analysis on the distribution of $\varphi$, q and n, it is able to apply in the aging analysis of power cable which visual observation is impossible and distribution change of discharge signals offers much information for risk degree on aging progress of insulation materials.

• Molecules and Cells
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• v.44 no.3
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• pp.136-145
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• 2021

Senescent cells that gradually accumulate during aging are one of the leading causes of aging. While senolytics can improve aging in humans as well as mice by specifically eliminating senescent cells, the effect of the senolytics varies in different cell types, suggesting variations in senescence. Various factors can induce cellular senescence, and the rate of accumulation of senescent cells differ depending on the organ. In addition, since the heterogeneity is due to the spatiotemporal context of senescent cells, in vivo studies are needed to increase the understanding of senescent cells. Since current methods are often unable to distinguish senescent cells from other cells, efforts are being made to find markers commonly expressed in senescent cells using bulk RNA-sequencing. Moreover, single-cell RNA (scRNA) sequencing, which analyzes the transcripts of each cell, has been utilized to understand the in vivo characteristics of the rare senescent cells. Recently, transcriptomic cell atlases for each organ using this technology have been published in various species. Novel senescent cells that do not express previously established marker genes have been discovered in some organs. However, there is still insufficient information on senescent cells due to the limited throughput of the scRNA sequencing technology. Therefore, it is necessary to improve the throughput of the scRNA sequencing technology or develop a way to enrich the rare senescent cells. The in vivo senescent cell atlas that is established using rapidly developing single-cell technologies will contribute to the precise rejuvenation by specifically removing senescent cells in each tissue and individual.