• Journal of Global Scholars of Marketing Science
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• v.17 no.4
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• pp.175-199
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• 2007

The linear regression method was used to model the relationship among a set of perceptions regarding to the importance of physical exercise and the perceived value of physical exercise (as a leisure activity) for aging baby boomers. In terms of a pilot study, we developed two alternative models tested at two different convenience samples. The first sample consisted of 82 aging baby boomers aged 55.65 (sample 1) and the second one consisted of 458 citizens aged 18.45 (sample 2). Through this research approach, we intended to lead to a better understanding of perceived value of physical exercise in the sporting goods marketing context for aging baby boomers. We addressed the core research themes of our study using a convenience survey. Data was collected by means of face to face interviews during the seven week period. The research results showed that the "model 2" better predicts perceived value of physical exercise as a leisure activity for aging baby boomers. We believe that the final findings of our research try can recognize the differences in buying behaviors between aging baby boomers and other target markets and advance marketers of sporting goods strategic tries regarding to consumer strategy management at a store level.

• Korean Chemical Engineering Research
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• v.52 no.2
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• pp.166-174
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• 2014

This research investigated the aging properties of the $B-KNO_3$ system as the igniter. The $B-KNO_3$ system showed the degradation in ignition properties depending on the method and period of storage. It should be found out the cause of the degradation to predict the reliability of the igniters. The changes of the properties by the degradation after aging tests were analyzed by microstructure analysis, XRD analysis and thermal analysis using DSC. It was found out that the lattice parameters of the $KNO_3$ as the oxidizer in the ignition system was changed into the JCPDS values as the aging time increased. Conclusively, the changes of the crystal structure of oxidizer affected the activation energy increasing as aging time increased.

• Proceedings of the Korean Society For Composite Materials Conference
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• 2005.11a
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• pp.39-44
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• 2005

The effects of aging of PSF/AS4 laminates on fatigue was studied using the new energy release rate analysis. The analysis by the variational mechanics has been useful in providing fracture mechanics interpretation of matrix microcracking in cross-ply laminates. This paper describes the changes of the critical energy release rate (microcracking toughness) according to the aging period under fatigue loading. The master plot by modified Paris-law gives a characterization of a material system's resistance to microcrack formation. PSF $[0/90_{s}]_{s}$ laminates were aged at four different temperature based on the glass transition temperature for 0 to 60 days. At all temperatures, the toughness decreased with aging time. The decrease of the toughness at higher temperature was faster than at lower temperature. To assess the effects of aging on fatigue, the unaged laminates were compared with the laminates which had been aged for 60 days at 170$^{\circ}C$ near 180 $^{\circ}C$ t$_g$. The slope of dD/dN versus ${\Delta}G_m$. of the aged laminates was lower than that of the unaged laminates. There was a significant shift of the aged data to formation of microcracks at the lower values of ${\Delta}G_m$.

• Korean Journal of Food Science and Technology
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• v.21 no.6
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• pp.760-765
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• 1989

The change of volatile flavor components In nutmeg (Kernels of the fruits of Myristica fragrans Houttuyn) during aging at $37^{\circ}C$ were studied by using a fused silica capillary GC & GC/MS. Volatile flavor components having the low boiling point showed a general decrease during aging, but those of the middle and high boiling point showed a reactionary tendency Myristicin and myristic acid among volatile flavor components showing the high boiling point had the amount increased considerably, and those were composed of 24.50% and 18.69% in aging for 6 months, respectively. The amount of whole volatile flavor concentrate showed the increased tendency till the aging period for 4 months, and then subsequently decreased.

• Physical Therapy Korea
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• v.5 no.1
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• pp.63-78
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• 1998

The decrease of muscle power and muscle size between twenties and seventies was about 30% and 40% respectively. The loss of muscle mass by aging resulted in the decrease of muscle power. The loss of muscle mass was due to the decrease of number of Type I fiber and Type II fiber and size of each muscle fiber. The aging skeletal muscle didn't show the loss of glycolysis capacity but showed 20% decrease of the oxidative enzymes and muscle vascularization. The vigorous endurance exercise training with graded intensity played a role in the vascular proliferation, increase of activity of oxidative enzymes and improvement of $VO_2$ max. The graded resistance exercise also played a role in the muscle hypertrophy and increase of muscle power, if it performed with adequate intensity and period. The exercise adaptation of aging skeletal muscle prevented it from sarcopenia, provided the activity of daily living with great effect and provided the aging related disease, that is Type II diabetes mellitus, arteriosclerosis, hypertension, osteoporosis and obesity, with great effect.

• The Journal of Advanced Prosthodontics
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• v.16 no.1
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• pp.48-56
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• 2024

PURPOSE. To evaluate the metameric disparities among monolithic zirconia materials with differing yttrium compositions across various lighting conditions. MATERIALS AND METHODS. Thirty-six square-shaped zirconia samples measuring 10 × 10 × 0.5 mm were prepared from monolithic zirconia materials with three different yttrium contents. A 0.2 mm thick layer of polymerized dual-polymerizable self-adhesive resin cement was created using a silicone mold with the same dimensions as the prepared zirconia specimens. To evaluate metamerism, color measurements were conducted using a spectrophotometer device on a neutral gray background in a color measurement cabinet that offers four different illumination environments. All samples underwent aging by subjecting them to 10000 thermal cycles using a thermal cycle tester. Following thermal aging, color measurements were taken once more, and the data were recorded using the CIE L^*, a^*, b^* color system. Two-way ANOVA and Post-hoc Bonferroni tests were employed to analyze the data. RESULTS. It was observed that there was no statistical difference among the color measurements made in different illumination environments of the monolithic zirconia ceramics used to evaluate metamerism (P > .05). This observation remained consistent both before and after thermal aging. After thermal aging, the color of monolithic zirconia materials exhibited a tendency towards red and yellow hues, accompanied by a decrease in brightness levels. CONCLUSION. It can be stated that different illumination conditions did not affect the metamerism of monolithic zirconia materials, but there was a color change in monolithic zirconia materials after a thermal aging period equivalent to one year.

• Journal of Ginseng Research
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• v.44 no.2
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• pp.222-228
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• 2020

Background: 20(S)-ginsenoside-Rg3 (C₄₂H₇₂O₁₃), a natural triterpenoid saponin, is extracted from red ginseng. The increasing use of 20(S)-ginsenoside Rg3 has raised product safety concerns. Methods: In acute toxicity, 20(S)-ginsenoside Rg3 was singly and orally administrated to Kunming mice and Sprague-Dawley (SD) rats at the maximum doses of 1600 mg/kg and 800 mg/kg, respectively. In the 26-week toxicity study, we used repeated oral administration of 20(S)-ginsenoside Rg3 in SD rats over 26 weeks at doses of 0, 20, 60, or 180 mg/kg. Moreover, a 4-week recovery period was scheduled to observe the persistence, delayed occurrence, and reversibility of toxic effects. Results: The result of acute toxicity shows that oral administration of 20(S)-ginsenoside Rg3 to mice and rats did not induce mortality or toxicity up to 1600 and 800 mg/kg, respectively. During a 26-week administration period and a 4-week withdrawal period (recovery period), there were no significant differences in clinical signs, body weight, food consumption, urinalysis parameters, biochemical and hematological values, or histopathological findings. Conclusion: The mean oral lethal dose (LD₅₀) of 20(S)-ginsenoside Rg3, in acute toxicity, is above 1600 mg/kg and 800 mg/kg in mice and rats, respectively. In a repeated-dose 26-week oral toxicity study, the no-observed-adverse-effect level for female and male SD rats was 180 mg/kg.

• 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.

• Transactions of the Korean Society of Pressure Vessels and Piping
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• v.7 no.4
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• pp.12-18
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• 2011

The renewed global interest in nuclear power has arisen from the need to reduce greenhouse gas emissions and to provide sufficient electricity for a growing global population. Many countries with nuclear power plants (NPPs) are still implementing license extensions of 10~20 years, and even consideration is being given to the concept of life-beyond-60, a further period of license extension from 60 to 80 years. To solve the materials aging problem is integral to its success. A foundation for effective aging management of nuclear power plants is that aging is properly taken into account at each stage of a plant's lifetime, i.e. in design, manufacture, construction and operation including long term operation and decommissioning. To evaluate the plant aging phenomena, a lot of background information such as materials and environment of the parts of the reactor and plant systems is needed by the experts. Information on degradation mechanisms is also used. In this paper, a regulation on the integrated materials aging management for nuclear facilities is proposed. The proposed regulation identifies key elements of effective aging management for nuclear power plants and provides the requirements on aging management for nuclear facilities throughout all stages of the lifetime of the plant.

• Food Science of Animal Resources
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• v.39 no.3
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• pp.510-519
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• 2019

The effect of combined electron-beam irradiation and aging temperature of pork on microbiological and physicochemical properties was investigated. The samples from pork shoulder were irradiated with 0 or 2 kGy, vacuum-packaged, and assigned randomly to an aging temperature ($2^{\circ}C$, $10^{\circ}C$, or $25^{\circ}C$) during 8 d. On 4 d of aging at $25^{\circ}C$, total aerobic bacteria of non-irradiated ones reached 7 Log CFU/g which is no salable levels. Shear force values of irradiated meat after aging for 2 and 4 d at $25^{\circ}C$ was lower than those aged at $2^{\circ}C$. Irradiated samples at $2^{\circ}C$ had lower cooking loss after 2 and 8 d of aging, compared with other aging temperatures. Irradiation did not accelerate 2-thiobarbituric acid reactive substance (TBARS) value when aged up to 4 d. Irradiated samples aged at $10^{\circ}C$ and $25^{\circ}C$ for 8 d scored significantly higher TBARS values. With an increased aging period, $a^*$ and $b^*$ in irradiated samples at $2^{\circ}C$ slightly increased, but irradiation caused negligible changes in meat color. The highest contents of a desirable nucleotide flavor compounds (inosine-5-phosphate) were observed in pork at $2^{\circ}C$ when aged for 4 and 8 d, while the lowest contents were observed at $25^{\circ}C$. Aging in irradiated pork for 8 d at $2^{\circ}C$ resulted in optimal condition with improved meat quality and minimal microbiologically negative defect.