• Journal of Ocean Engineering and Technology
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• v.23 no.4
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• pp.52-57
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• 2009

The effect of aging treatment on the microstructure and mechanical properties of super duplex stainless steel with W was investigated. The phase was precipitated mainly at the early stage of aging and a lower aging temperature under $750^{\circ}C$, but the phase was formed after long-term aging treatment between $600^{\circ}C$ and $900^{\circ}C$. The volume fraction of the phase increased with aging temperature up to $750^{\circ}C$ and then decreased up to $900^{\circ}C$. With an increase in the aging time, the volume fraction phase at the early stage of aging increased slightly, and then increased rapidly beyond a certain time. The rapid increase in the tensile strength and hardness and decrease in the elongation and impact toughness were measured with aging temperatures up to $750^{\circ}C$. On the other hand, the tensile strength and hardness decreased slightly, and the elongation and Charpy impact toughness were unchanged with aging temperatures over $750^{\circ}C$. The tensile strength and hardness increased rapidly at the early stage of aging, and then increased slowly beyond a certain time. The elongation and Charpy impact toughness decreased rapidly at the early stage of aging, and then remained unchanged beyond a certain time. The phase that formed at the early stage of aging and the lower aging temperature had a considerable effect on the elongation and Charpy impact toughness of the super duplex stainless steel with W.

• Journal of Acupuncture Research
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• v.21 no.3
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• pp.235-248
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• 2004

It has been investigated about aging theory. However, aging mechanism still remains to be unknown. Aging and aging related diseases might be due to oxidative damage and these were modifiable by genetic and environmental factors. For designing an optimal medical treatment and countermeasure against aging and aging related disease, it is necessary to understand the aging mechanism. Acetylcholine(Ach) plays an important role in memory. If someone doesn't have enough Ach, he has a tendency to catch a Alzheimer's disease. Corydalis tuber has been clinically used to treat heart disease, gastrointestinal disease and other diseases including endocrine disease in Oriental medicine. The purpose of this article is to investigate the inhibitory effect on Acetylcholinesterase and scavenging effects on NO, DPPH of Corydalis tuber Acua-acupuncture solution(CTAS). The results are summerised as follows; 1. There is a significant inhibitory effect of $0.01mg/m{\ell}$ CTAS group at 20, 30, 60 minutes and $0.1mg/m{\ell}$ CTAS group at 10, 20, 30, 60 minutes on AchE. 2. There is no significant scavenging effect of CTAS on NO. 3. There is a significant scavenging effect of $0.1mg/m{\ell}$ and $0.01mg/m{\ell}$ CTAS group at 10 minutes but there is no significant scavenging effect at 20, 30, 60 minutes on DPPH. There is a significant scavenging effect of $1mg/m{\ell}$ CTAS group at 10, 20, 30, 60 minutes on DPPH.

• Culinary science and hospitality research
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• v.5 no.2
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• pp.165-190
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• 1999

There are no reliable data about the effect on the baking industry in Korea yet. The damage caused by the product's aging is so much in the confectionary and baking industries. Therefore, the aging of bread is an economical problem which determines its commercial lifespan. In order to solve out this aging problem, this article dealt with the factors which give rise to the effect of starch on the aging and its inhibitory methods. 1. Control of the moisture content : Because the aging of starch occurs at 30~60% of moisture most frequently, controlling the moisture content above or below the above percentage can help restrain the aging to a certain degree. 2. Addition of sugars : The sugars become hydrated through hydrogenation with the moisture in the food. Thus, the sugars suppress the phenomenon of crumbling inside the food acting as a kind of dehydrator. 3. Use of an emulsifying agent : The emulsifying agent increases the stability of starch colloid liquid and suppresses the precipitation of starch molecules and the formation of crystallized range to prevent aging. 4. Method by freezing : The aging of starch does hardly occur reaching -2$0^{\circ}C$~-3$0^{\circ}C$ below zero. 5. Maintenance of warm condition : The freshness of bread is maintained at the 80% of humidity at 5$0^{\circ}C$.

• Korean Journal of Agricultural Science
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• v.43 no.1
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• pp.61-71
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• 2016

The effect of postmortem aging on the quality of Semimembranosus muscle (SM) from Hanwoo was investigated. The quality of SM was compared with that of Longissimus dorsi muscle (LD). SM contained higher moisture, protein, and ash, and lower fat than LD (p<0.05). The $a^*$ and $b^*$ values of SM were significantly decreased after 21 days of aging. SM showed higher $a^*$ values than LD at 1 and 7 day of aging (p<0.05). The cooking loss of SM was not affect by aging. SM had higher cooking loss than that of LD throughout the aging period. Although the shear force of SM was significantly decreased by aging, SM showed high shear force compared to LD during aging period (p<0.05). Aging increased lipid oxidation in both muscles (p<0.05). However, TBARS value of SM was significantly lower than that of LD throughout the aging period (p<0.05). There was no effect of aging on the betaine and L-carnitine contents of SM. SM contained higher betaine and L-carnitine than LD in all aging days (p<0.05). Therefore, we concluded that consumer acceptability of SM could be increased by aging based on the increase of tenderness in addition to its high nutritional properties.

• Transactions of Materials Processing
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• v.5 no.4
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• pp.327-336
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• 1996

The effect of dynamic strain aging on high temperature deformation behaviour of the A-Mg alloy was investigated by strain rate change tests and stress relaxation tests between 20$0^{\circ}C$and 50$0^{\circ}C$. Yield point, short stress transient and periodic discontinuities on the stress-strain curve were considered as an evidence of the effect of dynamic strain aging. With this criterion two distinct strain rate-temperature regimes could be manifested. Dynamic strain aging was considered to be effective in the high temperature-low strain rate regime, whereas dynamic recovery was a dominant deformation mechanism in the low temperature-high strain rate regime. It was found that dynamic strain aging in the high temperature deformation was governed by the mechcanism of diffusion-controlled, viscous dislocation movement.

• Journal of Industrial Convergence
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• v.21 no.5
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• pp.109-122
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• 2023

The purpose of this study is to look into how elderly people's health promoting behaviors influence their successful aging, to realize how their perception of successful aging and their life satisfaction have the mediating effect on the path from health promotion behaviors to successful aging, and to find the significant influence of successful aging perception and life satisfaction on successful aging. This researcher conducted a questionnaire survey with elderly people using a senior welfare center in Gyeonggio-do, and analyzed 250 copies that. For data analysis, SPSS Win 25 was applied to conduct frequency analysis, descriptive statistics, t-test, one-way ANOVA, and correlation analysis. Mediating effect analysis was made to verify the causal relations between health promoting behaviors and successful aging, and to validate the mediating effect of successful aging perception and life satisfaction on the causal relations. As a result, elderly people's health promoting behaviors influenced their perception of successful aging, their life satisfaction, and their successful aging. Their perception of successful aging had the mediating effect on health promotional behaviors and successful aging, but life satisfaction did not so. This study has the following implications: it is necessary to train persons specializing in support for health promoting, to develop an efficient health promotional model and program, and to provide an opportunity of education. It is necessary to come up with a support policy in consideration of tangible or intangible factors. It is necessary to establish a policy in line with economic levels and health conditions of elderly people.

• Journal of Sensor Science and Technology
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• v.26 no.4
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• pp.292-296
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• 2017

It has become ever harder to design reliable circuits with each nanometer technology node under normal operation conditions, a transistor device can be affected by various aging effects resulting in performance degradation and eventually design failure. The reliability (aging) effect has traditionally been the area of process engineers. However, in the future, even the smallest of variations can slow down a transistor's switching speed, and an aging device may not perform adequately at a very low voltage. Because of such dilemmas, the transistor aging is emerging as a circuit designer's problem. Therefore, in this paper, the impact of aging effects on the delay and power dissipation of digital circuits by using nanomneter MOSFET power gating structure has been analyzed.. Based on this analyzed aging models, a reliable digital circuits can be designed.

• Proceedings of the Korean Geotechical Society Conference
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• 2005.03a
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• pp.916-923
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• 2005

In this study, to observe aging effect of undrained shear behavior for Nak-Dong River sand, undrained static and cyclic triaxial tests were performed with changing relative density ($D_r$), consolidation stress ratio($K_c$) and consolidation time. As a result of the test, the modulus of elasticity to all samples estimated within elastic zone by the micro strain of about 0.05% in case of static shear behavior increased with the lapse of consolidation time significantly, so aging effect was shown largely. Also strength of phase transformation point(S_{PT}$) and strength of critical stress ratio point($S_{CSR}$) increased with the lapse of consolidation time. Undrained cyclic shear strength($R_f$) obtained from the failure strain 5% increased in proportion to relative density($D_r$) and initial static shear stress($q_{st}$), $R_f$ of consolidated sample for 1,000 minutes increased about 10.6% compared to that for 10 minutes at the loose sand, and $R_f$ increased about 7.0% at the medium sand. In situ application range of $R_f$ to the magnitude of earthquake for Nak-Dong River sand was proposed by using a increasing rate of $R_f$ as being aging effect shown from this test result.

• The Journal of the Korea Contents Association
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• v.17 no.2
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• pp.595-611
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• 2017

This study aims to verify the effect that familism recognized by college students has on anxiety over aging and elderly group's attitude as well as mediation effect of a sense of filial duty. For study analysis, 200 college students studying at colleges in Sungnam, Anyang and Incheon in Gyeonggido as well as in Seoul were surveyed using structured questionnaires from May 2, 2016 to June 28, 2016. All of 166 responses except for 34 incomplete ones were used for analysis. Firstly, analysis result confirmed correlation among familism, anxiety over aging, elderly group's attitude and variables in sense of filial duty. Multicollinearity between variables were confirmed using VIF values. Secondly, the effect that familism recognized by college students has on anxiety over aging and elderly group's attitude was confirmed. Thirdly, partial mediation effect of a sense of filial duty was confirmed in the effect that familism recognized by college students has on anxiety over aging. In addition, Sobel Test suggested by Sobel was conducted to verify significance of the mediation effect. This study suggests intervention in and practice of social welfare to promote familism and a sense of filial duty between college students and elderly generation in this era of nuclear family and aging society as well as reduction of anxiety over aging on the part of college students, based on the verified mediation effect of a sense of filial duty in the effect that familism recognized by college students in aging society has on anxiety over aging.

• Korean Journal of Metals and Materials
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• v.49 no.6
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• pp.448-453
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• 2011

Pre-aging heat treatment after solution heat treatment (SHT) of Al-0.4 wt%Mg-1.2 wt%Si-0.1 wt%Mn alloy sheets for auto-bodies was carried out to investigate the effect of pre-aging and its conditions on the bake-hardening response. Mechanical properties were evaluated by a tensile and Vickers hardness test. Microstructural observation was also performed using a transmission electron microscope (TEM). It was revealed that pre-aging treatments play a great role in the bake-hardening response. In addition, it was found that the sphere-shaped nanosized clusters that can directly transit to the needle-shaped ${\beta}$" phase during the paint-bake process, not being dissolved into the matrix, are formed at 343 K. The result, reveals that the dominant factor of the bake-hardening response is the pre-aging temperature rather than the pre-aging time.