• Journal of the Korean Society for Heat Treatment
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• v.8 no.1
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• pp.65-74
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• 1995

This research was performed to investigate the effect of ageing on grain refinement of 82wt%Cu-13.5wt%Al-4.5wt%Ni-0.1wt% misch metal alloy with ageing temperature and time. The results obtained in this study are as follows; The variation of transformation temperature with ageing temperature had very influence on ageing time at $300^{\circ}C$. But it had not influence on ageing time at $100^{\circ}C$. The variation of transformation temperature after second reversed transformation cycle was not occured in martensitic phase ageing, but $M_s$ point was appeared equally with third reversed transformation cycle in parent phase ageing. The variation of $M_s$ point was not nearly with ageing time at $100^{\circ}C$ ageing temperature. But it was decreasing with ageing time at $300^{\circ}C$ ageing temperature and $A_s$ point was increasing with ageing time. Structure of parent phase ageing was being M18R martensitic and N2H martensitic phase. It was found that ${\alpha}$ and ${\gamma}_2$ phase were created by ageing of long time at $300^{\circ}C$ ageing temperature.

• Journal of Korean Society of Rural Planning
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• v.20 no.4
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• pp.183-192
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• 2014

The purpose of this study is to examine the effect of regional ageing rate to industrial structures of rural areas in Korea. This paper shows that there are cause-effect relations between the industrial specialization and ageing rate in 'Agriculture', 'Finance & Insurance', and 'Real Estate & Leasing' sectors. The ageing levels are classified into ageing society, aged society, and super-aged society according to UN standard that cause different impacts on industrial specialization of regions. This paper finds that the industrial specialization is determined by the ageing levels. If there is an increase in ageing rate by 1% in ageing society, the industrial specialization of the three industries could be strengthened by 0.14%. But, ageing rates have negative impacts on the industrial specialization in aged society and super-aged society by 0.76% and by 1.20%, respectively, as increasing ageing rate by 1%. As the ageing rate progresses, 'Agriculture', 'Finance & Insurance' and 'Real Estate & Leasing'sectors have positive impacts on the industrial specialization in the ageing society. But 'Finance & Insurance' and 'Real Estate & Leasing' sectors have changed into negative impacts on the industrial specialization in the aged society. In the aged society, the employment of elderly persons of 'Agriculture' and 'Finance & Insurance' sectors increase by 1% makes positive impact on the industrial specialization by 1.54%, by 0.45%, respectively. The result of this paper can be applied to a significant guideline at establishing regional employment planning such as elderly customized employment, vocational training for rural areas, where above 14% of ageing rate.

• YAKHAK HOEJI
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• v.6 no.2
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• pp.7-12
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• 1962

The rats of thermal ageing at elevated temperatures and heats of activation of aluminum hydroxide gel have been determined. The ageing was expressed in terms of diminution of acid consuming capacity. Although the actual rates of ageing were different by the samples, the slopes of their Arrhenius plots were the same. This may indicate similarity of ageing mechanisms and heats of activation of samples. The heat of activation was the mangitude of 30 Kcal/mole. Thus, rates of ageing of aluminum hydroxide gel may be greatly accelerated at elevated temperatures.

• KSBB Journal
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• v.26 no.3
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• pp.183-188
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• 2011

Adult stem cells, which have characteristic of self-renewal and multipotency, are specialized cell types, responsible for the tissue regeneration of the damaged tissue. Recent studies suggest that stem cells senescence (or stem cells' ageing) is closely associated with the variety of ageing-related phenotypes such as tissue atrophy, degenerative diseases and onset of cancers. During ageing, declining of stem cells function and subsequently occurring mal-differentiation of stem cells would be important to understand the biological process of development of ageing-related phenotypes such as tissue degenerations and cancers. This review focuses on the DNA damage stress as a cause of senescence of stem cells and their mal differentiation, which is closely link to defect of regeneration potentials and neoplastic transformation. Understanding of molecular mechanisms governingsuch events is likely to have important implications for developing novel avenues for balancing tissue homeostasis longer period of time, further leading to 'Healthy ageing'.

• Nuclear Engineering and Technology
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• v.9 no.3
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• pp.117-123
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• 1977

The strain ageing behaviour of quenched Zircaloy--4 has been studied as a function of ageing time and temperature in the temperature range 523 to 588 K for a short-ageing time of 1 to 52 seconds. At the test conditions, the strain ageing stress increased with ageing time and temperature at a strain rate of 5.55$\times$10$^{-4}$ sec$^{-1}$ . Applying stress on the Quenched Zircaloy-4, the strain ageing effect indicated following two stages: an initial stage having an activation energy of 0.39 ev considered to be due to Snoek type ordering of intersitial oxygen atoms in the stress field of a dislocation and a second stage having an activation energy of 0.60 ev, due to mainly long-range diffusion of oxygen atoms.

• Human Ecology Research
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• v.53 no.3
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• pp.309-318
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• 2015

This study investigates to investigate the ageing effect on household demand for clothing, food, housing and medical care commodities in Korea using a demand system model. The cross-sectional and time-series data from Statistics Korea on urban household expenditures and age projection analyzed household demands of consumption commodities. The household head age and elderly population ratio were employed for proxy variables of ageing. Ageing variable elasticities of commodity demands were estimated. Study results show that ageing variables significantly influenced on a household demand for commodities; clothing and food consumption decreases; however, housing and medical care consumption increases with ageing. The elasticities of total consumption expenditures and price variables were estimated in the demand analysis; these two variables significantly impacted almost all of the household consumption for the studied commodities. This study provides an opportunity to examine how ageing influences household consumption for clothing, food, housing and medical care commodities as Korean society experiences a rapid ageing. It is also meaningful that this study conducted a quantitative measuring of the household demands for commodities that was different from past research on the household consumption expenditures for commodities.

• Korean Journal of Culture and Social Issue
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• v.12 no.5_spc
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• pp.29-43
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• 2006

With longevity (75 years plus and still increasing) now commonly achievable, the new challenge for individuals and society is less concerned with adding more years to life, though that remains important, and more with adding life to years. To explore the quality of long life more fully, a concept broader than healthy ageing or active ageing is needed. For this purpose, the present article describes a framework of Positive Ageing, also known as Successful Ageing, which views the quality of long life as comprising good health, physical and cognitive functional independence, and meaningful engagement with life. Narrowly defined, it refers to old people ageing well in all these aspects. More broadly defined, it refers to ageing well from midlife on. The framework also identifiesvariables that may affect the process of ageing positively. These variables include the social-cognitive styles of control, humour and future-time perspective on the one hand, and on the other hand, resources based on finance, social network and lifestyle.

• Food Science of Animal Resources
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• v.35 no.3
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• pp.406-412
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• 2015

The combined effects of electron-beam irradiation and ageing of beef were examined. The irradiated samples at dose of 0 or 2 kGy were kept and analyzed for the microbial growth, shear values, meat color, and nucleotide-related flavor compounds at different ageing temperatures (2, 10, or 25℃) for 8 d. The irradiation effect on inactivation of foodborne pathogens was also investigated. The population of Listeria monocytogenes and E. coli O157:H7 inoculated in beef samples decreased in proportion to the irradiation dose, showing D₁₀ values of 0.66 and 0.65 kGy respectively. The irradiated beef eye of round had lower number of total aerobic bacteria (TAB) than nonirradiated one during the storage, but the TAB increased with higher ageing temperature (p<0.05). Especially, TAB increased sharply in non-irradiated samples aged at 25℃ after 4 d (p<0.05). With increasing ageing temperature and ageing time, shear force values decreased (p<0.05). The color a* values of the irradiated beef were lower than those of the non-irradiated throughout the ageing period (p<0.05). As ageing time and temperature increased, the amounts of inosine monophosphate decreased and the hypoxanthine increased (p<0.05). Relatively high ageing temperature could be used at irradiated beef eye of round to shorten the ageing time.

• YAKHAK HOEJI
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• v.18 no.1
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• pp.20-28
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• 1974

Physical studies of ageing inhibition of aluminum hydroxide gel were carried out. Sorbitol, mannitol and fructose were found to be an ageing inhibitor of the aluminum hydroxide gel. IR spectra and DTA curves showed that the ageing products of the gel by sorbitol orl mannitol were monohydrous alumina. This differs from hydrated hydrous alumina of other ageing products. This evidence indicates that sorbitol and mannitol prevent the hydrous alumina from its hydration.

• 한국노년학
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• v.31 no.3
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• pp.813-829
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• 2011

The purposes of this study were to explore the perception of risk regarding an ageing society and to suggest the ways of preparation for an ageing society. Based on the social constructionist paradigm from Slovic as to the perception of risk and the perspectives of new social risks fromTaylor-Gooby, we observed risk perception of an ageing society in two ways: ordering of perceived risks and risk perception. Social survey research method was used for this study and data collected from 1,500 subjects aged 20 and over were analyzed. The results revealed that the risk perception of an ageing society was ranked 7th out of 11 social risks. 'Whether or not one perceived he/she lived in an ageing society', 'an ageing society's effects on one's lives', and 'educational background' were the significant variables influencing the ordering of perceived risks of an ageing society. Also, perception of risk regarding an ageing society was significantly associated with 'relation of ageing society with his/her own life', 'an ageing society's effects on one's lives', and 'educational background'. Further discussion for the preparation of an ageing society was provided based on these results.