• Design & Manufacturing
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• v.16 no.2
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• pp.33-38
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• 2022

Currently, Korea is an aging society, and it is expected to enter a super-aging society in about 4 years. Accordingly, many X-ray technologies are being developed. In X-rays, 99% of X-rays are converted into heat energy and 1% into light energy (X-rays). 99% of the thermal energy raises the temperature of the anode and its surroundings, and the cooling system is an important factor as overheating can affect the deterioration of X-ray quality and shortened lifespan. There is a method of forced air cooling using natural convection. Therefore, in this study, when X-rays were taken 5 times, Flow analysis was performed on heat removal according to temperature rise and cooling time for the heat generated at the anode of the X-ray tube (input power 60kW, 75kW, 90kW). Based on one-shot, the most rapid temperature rise section increased by more than 57% to 0.03 seconds, A constant temperature rises from 0.03 seconds to 0.1 seconds, It is judged that the temperature rises by about 8.2% or more at one time. After one-shot cooling, the cooling drops sharply from about 60% to 0.03 seconds, It is judged that the temperature has cooled by more than 86% compared to the temperature before shooting. One-shot is cooled by more than 86% with cooling time after 0.1 seconds, As the input power of the anode increases, the cooling temperature gradually increases. Since the tungsten of the anode target inside the X-ray tube may be damaged by thermal shock caused by a rapid temperature rise, an improvement method for removing thermal energy is required when using a high-input power supply.

• Korean Journal of Materials Research
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• v.25 no.8
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• pp.403-409
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• 2015

Metastable phase characteristics of beta Ti alloys were investigated to consider the relationship of the microstructure and diffraction pattern in TEM. TEM analysis showed that the microstructure was mottled as a modulated structure, and the diffraction pattern was composed of spot streaks between the main spots of a stable beta phase with a specific lattice relationship. The modulated structure may be induced by short distance slip or atom movement during a very short interval of solution treated and quenched (STQ) materials. The athermal ${\omega}$ phase, which could be precipitated at low temperature aging, is also analysed by the metastable phase. The metastable phases including athermal ${\omega}$ phase had a common characteristic of hardened and brittle behavior because the dislocation slip was restricted by a super lattice effect due to short distance atom movement at the metastable state.

• Korean Journal of Materials Research
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• v.15 no.1
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• pp.19-24
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• 2005

For the good combination of high-temperature strength, toughness and creep property, $9-12\%$ chromium steels are often used for gas turbine compressors, steam turbine rotors, blade and casing. In this study, the correlation of microstructural evolution and mechanical properties was investigated fur the specimens heat-treated at 600, 650 and $700^{\circ}C$ for 1000, 3000 and 5000 hrs. The microstructure of as-received specimen was tempered martensite with a high dislocation density, small sub-grains and fine secondary phase such as $M_23C_6$. Aging for long-time at high temperature caused the growth of martensite lath and the decrease of dislocation density resulting in the decrease in strength. However, the evolution of secondary phases had influence on hardness, yield strength and impact property. In the group A specimen aged at $600^{\circ}C\;and\;650^{\circ}C$, Laves phase was observed. The Laves phase caused the increase of the hardness and the decrease of the impact property. In addition, the abrupt growth of secondary phases caused decrease of the impact property in both A and B group specimens.

• Journal of Broadcast Engineering
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• v.24 no.5
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• pp.859-869
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• 2019

We are facing an era of automation where artificial intelligence works and an era of super-aging, where birth is rapidly declining. In this paper, we intend to perform the creation of an autobiography in conjunction with the generation integrated narrative storytelling, thereby exploring the potential for visual storytelling that can be extended to a variety of media format. The visual autobiography production program confirmed through an interview with the production participants that grandparents, grandchildren and granddaughter together became the main characters in the documentary, a valuable opportunity to reflect on their past memories and lives and recognize their meaning of life. The visual storytelling education program model and media life service presented in this paper will be shared by the youth and the elderly generation together and contribute to the 'sympathetic culture' as a social integration program.

• Journal of Power System Engineering
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• v.19 no.6
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• pp.75-81
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• 2015

A deposited metal specimen of ER2594 which is a super duplex steel welding wire used to investigate the effect of sigma(${\sigma}$) phase on electrochemical corrosion characteristics was prepared by gas tungsten arc welding. Aging treatment was conducted for the specimen at the temperature range of $700^{\circ}C$ to $900^{\circ}C$ for 5 to 300 minutes after annealing at $1050^{\circ}C$. Corrosion current density has decreased a little with an increase of aging time over 60 minutes at $700^{\circ}C$ to $900^{\circ}C$ and the uniform corrosion of deposited metal had more influence on the precipitation of ferrite than the precipitation of sigma phase. Therefore, the precipitation of sigma phase did not have much effect on the uniform corrosion. Pitting potential representing pitting corrosion has shown decreasing tendency as the precipitation of sigma phase increased. The degree of sensitization representing intergranular corrosion has shown increasing tendency as the precipitation of sigma phase increased at $700^{\circ}C$ to $800^{\circ}C$, while it has decreased at $900^{\circ}C$ for 60 to 300 minutes.

• Journal of Local Government Studies
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• v.26 no.2
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• pp.87-112
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• 2014

The entry of aging society and the coming of (super) aged society need overall the elderly welfare policy and budget for quantitative expansion and qualitative increase to the elderly welfare services. However, financial limit to the elderly welfare and increase to elderly welfare services in local government rely on central government or private sector. This study is discussed the gap between demands and supplies of the elderly welfare services in Busan Metropolitan City and policy implications suggested by these results. The major findings of the study are summarized as follows. First, the rate of the poor elderly under minimum living standard and the elderly housing facilities in demand of the elderly welfare services is reduced, but other measuring indicators are generally increased. Second, a per 10,000 elderly welfare service officials and a per 10,000 elderly medical welfare facilities in supply of the elderly welfare services are generally increased, but other measuring indicators are reduced. The policy implications of the study is to reduce the poor elderly under minimum living standard, to expend the elderly welfare budget, and adequately to supply a variety of the elderly welfare facilities for reduce demand of the elderly welfare services.

• Journal of dental hygiene science
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• v.24 no.2
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• pp.107-114
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• 2024

Background: This study aimed to analyze trends in oral health research among people with disabilities. Methods: Data were obtained from 70 oral studies on individuals with disabilities from 2000 to 2024. Keywords were analyzed. Frequency, betweenness centrality, and cluster analyses were performed using NetMiner. Results: The main keywords for oral health research on disabled people were oral health, dental caries, DMFT (decayed-missing-filled-teeth), dental treatment, oral health centers, and disabled children. As a result of the centrality analysis, DMFT had the highest connectivity, followed by disabled children, special care dentistry, oral health behavior, periodontitis, and health insurance. Cluster analysis results of research on disabled people: Group 1, oral diseases and functions of disabled people; Group 2, oral care for disabled children; Group 3, dental treatment for disabled people; Group 4, oral health policy; Group 5, oral care by dental hygienists; and Group 6, conservative dentistry. Conclusion: Considering the increase in the number of disabled people in a super-aging society, research on ways to promote oral health for disabled people, oral health policies, and training of oral health experts for disabled people is required.

• The Journal of Industrial Distribution & Business
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• v.9 no.11
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• pp.7-15
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• 2018

Purpose - This study surveys factors such as lifestyles, nutritional status, physical indicators, and physical fitness levels that affect the health of seniors over the age of 65 and based on the collected data attempts to create a senior health index model that provides health service information, help support seniors' successful aging, and improve their quality of life. Research design, data, and methodology - This paper conducted the development for senior health index model and the cross validity verification to examine the status of senior health level, and aimed at setting the health status evaluation criteria. Seniors 384 usable data were analyzed. Results - As an attempt to segment the senior health service market, I divided the results of this study based on measurability, accessibility, disparity between groups, and the size of the potential client base. I divided the senior market into five subgroups: very healthy, healthy, normal, weak, and very weak. Conclusions - The findings of this study may prove useful in preparing for the forthcoming super-aged society through segmentation of the senior market, understanding differences between groups with different health conditions, and discovering effective marketing strategies that meet the demands of different senior groups.

• Korean Journal of Materials Research
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• v.7 no.2
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• pp.129-135
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• 1997

This study has investigated the effects of aging treatment on thc nlechanical propcrries of blg-iiAl-x%nix - 0.1.2) alloys fabricated by the squeeze castmg process. The microstructurcs of as-squeeze cast were composed of pro eurectic $\alpha$ magnesium solid solution, super saturated $\alpha$ solid solution and $\beta(Mg_{17}AI_{12}$) compund. Agcd at both $200^{\circ}C$ and $240^{\circ}C$, Mg--6AixZn alloys showed the peak hardness due to the formation of $\beta(Mg_{17}AI_{12}$) precipitates. The tiiscontinuous precipitates of the lamella r\.pe are predominant at $200^{\circ}C$ aging tredrment. tvhilc. the finely dispersed continu ous precipitates were major type at $240^{\circ}C$ treatment. Mg-- GAI-xZn a1loi.s fabricated hy the squeeze casting process had the hetter combination of tensile strength and elongation compared to the conventionally cast alloys. As increascci zinc: contents. the tensile strength was increased 11y the soiid solutirin strengthening effect of zinc,.

• Journal of the Korean Society of Safety
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• v.37 no.6
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• pp.102-107
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• 2022

South Korea will soon be a super-aged society, as more than 20.6% of its population will be 65 years and older by 2025. As of 2022, 17.5% of the total population in South Korea is 65 years and older, which exceeds the set threshold for an aged society, where more than 14% of the population is 65 years and older. The proportion of older subway construction workers has increased. Aging workers and their work stress negatively impact their workability. A previous study demonstrated that the stress index measured using the uBioMacpa measurement device (Macpa stress index) had a significant correlation with work stress in South Korea. The device tests vascular health and measures stress levels via Macpa signal analysis. In this study, the pulse waves of subway construction workers were measured using uBioMacpa to identify their stress levels. The stress levels were analyzed by age, years of service, job position, employment type, and work type. Herein, these statistics could not be easily represented by a normal distribution; therefore, the Kruskal-Wallis test, a nonparametric statistical method, was used for the analysis of data. The results showed that age, job position, employment type, and working type affected the Macpa stress index and the stress levels of workers increased with age. In terms of job position, technical engineers were more stressed than other workers because of their poor working environment. In terms of employment type, daily-wage workers were more stressed than other workers. In terms of working type, tunneling, waterproofing, and construction scored the highest Macpa stress indexes without any significant difference, whereas earthworks scored the lowest. Based on the analysis of Macpa stress index, safety and health management plans were proposed to reduce the stress levels of workers. Moreover, a manual for efficient stress management must be developed for subway construction workers.