• Korean Journal of Culture and Social Issue
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• v.22 no.2
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• pp.137-163
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• 2016

The purpose of this study is to compare rational process of active ageing and productive aging based on the theory of planned behavior. The effect of post-retirement may be influenced by attitude, subjective norms, and perceived behavioral control for old aged workers, then we tested the effect of mediating role of post-retirement preparation on active ageing and productive aging. And we conducted additional analyses of mediating role of post-retirement preparation respectively. Conducting a survey research to 192 employed old aged workers, the data was analyzed by Structural Equation Modeling. The result of this study found the positive effects of attitude and perceived behavioral control on active ageing through post-retirement preparation. There were negative effect of subjective norms and positive effect of perceived behavioral control on productive aging through post-retirement preparation. According to additional analyses, the mediating effect of social post-retirement preparation was significant on active ageing, and the mediating effect of emotional and social post-retirement preparation was significant on productive aging. Suggestions for future research and practical implications were provided based on the findings.

• Journal of Acupuncture Research
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• v.20 no.2
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• pp.184-194
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• 2003

Objective : This study was designed fo find out whether Astragali Radix Herbal-Acupuncture Solution(ARHA) can scavenge NO, DPPH and IL-4 or not. Astragali Radix has been clinically used to reforce the depression of immune reponse etc. in Oriental Medicine. Methods : Free radical metabolism seems to occupy a remarkably common position in the mechanisms of ageing and ageing related disease. Oxidative damage to DNA, lipids, proteins and other molecules may contribute to the development of cancer, cardiovascular disease and possibly neurodegenerative disease. The effects of ARHA on NO, DPPH and IL-4 were measured. Results : The followings are the summary of the result; (1) There is a significant scavenging effect of ARHA on NO in 1, $10mg/m{\ell}$ group in after 24hrs. (2) There is no significant scavenging effect of ARHA on DPPH. (3) There is a significant scavenging effect of ARHA on IL-4 in 1, $10,100{\mu}g/m{\ell}$ group. Conclusions : These results suggest that ARHA has significant scavenging effect on NO, IL-4 and not on DPPH. This study shows that ARHA can be used for ageing related disease and further studies are required to investigate the antioxidative effects of it.

• JSTS:Journal of Semiconductor Technology and Science
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• v.13 no.6
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• pp.668-675
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• 2013

We investigate the effect of the ageing time and etching time on the etching rate of SiGe mixed etching solution, namely 1 vp HF (6%), 2 vp $H_2O_2$ (30%) and 3 vp $CH_3COOH$ (99.8%). For this etching solution, we found that the etch rate of SiGe layer is saturated after the ageing time of 72 hours, and the selectivity of $Si_{0.8}Ge_{0.2}$ layer and Si layer is 20:1 at ageing time of 72 hours. The collapse was appeared at the etching time of 9min with etching solution of after saturation ageing time.

• Journal of the Korean Society for Heat Treatment
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• v.33 no.4
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• pp.161-172
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• 2020

The tensile property of A5082 and A6060 aluminium wrought alloys was investigated, in terms of the strain rate sensitivity on alloy conditions by heat treatment and bake hardenability on pre-strain prior to strain ageing. The tensile test was carried out in a range of strain rate of 4.17 × 10^-5 s^-1 ~ 4.17 × 10^-5 s^-1 in room temperature and the nominal range of pre-strain was 3.0 ~ 10.5%. The tensile deformation of A5082 alloys is characterized as typical case of dynamic strain ageing with negative strain rate sensitivity for all conditions, and the tensile strength indicates a similar level regardless of alloy conditions, except only in full annealed condition. The stress-relief annealing on A6060 alloys can induce practical decrease in strength level of over approximately 100 MPa without any ductility loss, compared to as-rolled condition, while a full annealed and aged condition leads remarkable strengthening effect with the decrease of tensile elongation. Additionally, the bake hardenability of A5082 alloy by strain ageing indicates a negative dependence upon the increase of pre-strain, while A6060 alloy exhibits a positive sign even in low level relatively compared with conventional SPCC.

• Journal of the Korean Society of Safety
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• v.20 no.3 s.71
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• pp.27-33
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• 2005

The shape memory effect in Ti-50.4at.%Ni alloy after solution treatment at 1273K for 2h and aged at 350, 450, $550^{\circ}C$ for 0.5, 1, 1.5, 2, 4, 10hrs had been investigated by differential scanning calorimetry measurement. It was found that ageing in the temperature range of $350^{\circ}C{\sim}550^{\cric}C$ induced complex transformation behavior, involving the R-phase and multiple-stage martensitic transformation. Usually aged Ni-rich NiTi alloys undergo martensitic transformation on cooling from high temperatures in two step : Austenite to R-phase and then R-phase to Martensite (normal behavior). In sample aged at $350^{\circ}C$ two distinct DSC peaks arised giving evidence of intermediate stages of martensite transformation. This results in the nucleation and growth of coherent $Ni_4Ti_3$-precipitate. These explain all features of the evolution of DSC charts during ageing including the number of distinct DS peaks and their positions.

• Elastomers and Composites
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• v.17 no.1
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• pp.13-21
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• 1982

The purpose of this dissertation is to compare bound andtioxidant, MHPPD with the ordinary one, IPPD, when high polymers are used like NR and SBR. The effect of rubber bound antioxidant and ordinary antioxidant on the Mooney scorch time has been studied by means of the Mooney viscometer. The ageing properties of vulcanizates containing rubber-bound antioxidant and ordinary antioxidant have been studied in terms of hardness, tensile strength and elongation. The results of the Mooney scorch time and ageing properties are as follows: When MHPPD was mixed with NR or SBR compounds, the Mooney scorch time was faster than the IPPD compounds. Also the ageing properties of the vulcanizates containing MHPPD were much superior to the IPPD compounds. Furthermore, the vulcanizates comporised of MHPPD have taken andvantage of and resistance in the ozone test.

• Animal Bioscience
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• v.35 no.2
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• pp.272-280
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• 2022

Objective: The aim of this study was to evaluate the effect of ageing and feeding strategies on the calpain protease system and meat quality traits in Braford steers. Methods: Thirty Braford steers were employed; 15 animals were supplemented with corn silage during finishing and 15 were kept only on pasture. Meat quality traits and calpain system protein activity were evaluated in longissimus thoracis et lumborum (LTL) steaks aged for 2, 7, 14, and 21 days. Results: Aged meat showed higher pH and calcium content, while Warner Bratzler shear force (WBSF) decreased to day 21. No interaction between ageing and diet was seen for quality traits. Steers finished with corn silage showed higher values of water holding capacity, WBSF and free calcium, and lower values of pH and cooking loss. Calpain and calpastatin activities decreased with ageing. Finishing steers on pasture produced higher values of calpains and lower values of calpastatin activities. The higher values of calpain 1 activity were observed in muscles aged 2 days from pasture finished animals, and the lower activity of the inhibitor in the 21 days aged samples of the same group. Conclusion: These results suggest a diet by ageing interaction in calpains and calpastatin and this interaction impact in Warner Bratzler Shear Force in Braford LTL muscle.

• Journal of Animal Science and Technology
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• v.48 no.2
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• pp.287-292
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• 2006

The purpose of this study was to assess the influence of ageing time on the meat quality and sensory characteristics of longissimus muscle in Jeju horses. Twenty four horses were slaughtered after 16hr fasting. Longissimus muscle was separated from the left half of the carcass after 24hr chilling. The muscle was sliced into 3cm-thick steaks for analysis. Steaks were vacuum packaged and aged at around 4℃ for 1, 3, 7, 12, 18 and 25 days respectively. Longissimus muscle pH was not influenced by ageing (P>0.05). But shear force values of the muscle decreased during ageing time (P<0.05). Water holding capacity, color characteristics, cooking loss and purge loss considerably increased as the ageing time increased (P<0.05). Also ageing had a very important effect on flavor, juiciness, tenderness and palatability characteristics (P<0.05) evaluated by the panel. Flavor and palatability were the most acceptable when the ageing time was 7 days, whereas, juiciness was 12 days. These results suggest that ageing improves the quality of horsemeat by increasing the meat tenderness, water holding capacity and sensory characteristics. Therefore Jeju horse meat need 7-12 days ageing period to obtain an optimum acceptance.

• Food Science of Animal Resources
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• v.27 no.2
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• pp.171-178
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• 2007

This study was conducted to investigate the effect of ageing temperature(0 and $4^{\circ}C$) and time(2, 7, 14, 21, 28, and 49 days) on the meat quality of longissimus muscle from Hanwoo steer. The pH, Warner-Bratzler shear force(WBSF), myofibrillar fragmentation index(MFI), cooking and purge loss, sensory, morphological changes, and amino acid composition were assessed. The pH of longissimus muscle increased significantly(p<0.05) for 21 days at $0^{\circ}C$ and 14 days at $4^{\circ}C$, but decreased thereafter. Longissimus muscle aged from 14 days to 28 days at $4^{\circ}C$ had a lower WBSF than longissimus muscle aged at $0^{\circ}C$(p<0.05). The WBSF of longissimus muscle decreased significantly(p<0.05) with ageing time. The MFI, cooking and purge loss, tenderness, and juiciness scores were higher for longissimus muscle aged at $4^{\circ}C$ than at $0^{\circ}C$. As ageing time increased, the MFI, cooking and purge loss, tenderness, juiciness, and amino acid composition of longissimus muscle increased significantly(p<0.05) with ageing at 0 or $4^{\circ}C$. Transmission electron microscopy showed Z-disk degradation and morphological changes of the myofibrils correlating with increased tenderness during the ageing time. Based on these results, the proper ageing conditions of longissimus muscle of Hanwoo steer were 14 days of ageing at $0^{\circ}C$ or 7 days of ageing at $4^{\circ}C$. However, further study on the application of ageing technology to this industry is necessary for the optimization of ageing conditions for the sub-primals or muscles from Hanwoo beef.

• Nuclear Engineering and Technology
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• v.36 no.4
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• pp.304-315
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• 2004

The ageing effects of radionuclides in radioactive soil on remediation using the electrokinetic method were analyzed. Comparative experiments were conducted for the reactive soil around a TRIGA research? reactor contaminated with $^{137}Cs\;and\;^{60}Co$ for 15 years and the non-reactive soil that was intentionally contaminated with $Cs^+\;and\;Co^{2+}$ for 3 days. It was observed that because of an aging effect on $^{137}Cs$, the efficiency of removing it decreased. $H_{2}SO_4$ used as an additive to increase the removal efficiency showed a higher removal capability than other chemicals for both $^{137}Cs\;and\;^{60}Co$. The efficiency of removing radionuclides from the radioactive soil in the column was proportional to the capability of the added chemical to extract radionuclides. It took 10 days to achieve a $54\%$ removal of $^{137}Cs$ and a $97\%$ removal of $^{60}Co$ from the soil. The volume of the soil wastewater discharged from the soil column by the electrokinetic method was $20\%$ below that for soil washing.