• Title/Summary/Keyword: aging degree

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A Study on Insulation Degradation Phenomena in 22kV CV Power Cable (22kV CV케이블에 있어서 절연열화현상의 고찰)

  • Kang, Moo-Seong;Kim, Dong-Shik;Jung, Seong-Yong;Park, Dae-Hee
    • Proceedings of the KIEE Conference
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    • 1996.07c
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    • pp.1797-1800
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    • 1996
  • In this study, the insulation selected in degra-dated-power cable has been observed and aging process about the insulation has been investigated. Most Insulation aging process initiates in the interface of semiconducting layer and the type of the process is the fractal form that was observed between the the semiconducting layer and insulation layer. It is possible to estimate degree of the degration of cable with breakdown test and obtained data have been used to get parameters in order to use Weibull distribution. With this method it is considered to be possible to estimate situation of degration and life prediction.

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Analysis of Photovoltaic module's Phenomena of aging with Acceleration Test (외부환경적 가속시혐에 의한 PV모듈의 열화성능 분석)

  • Kang, Gi-Hwan;Kim, Kyung-Soo;Park, Chi-Hong;Yu, Gwon-Jong;Ahn, Hyung-Gun;Han, Deuk-Young
    • Proceedings of the KIEE Conference
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    • 2006.07b
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    • pp.1151-1152
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    • 2006
  • In this paper, we examined 10 domestic samples of three different model using thermal, humidity freeze, thermal-endurance and damp heat test under IEC61215 photovoltaic module environmental endurance test condition. Three was almost no changes on power generation. Insulation resistance capacity was much higher than judgement standard but, showed unstable results depending on environmental test items. On external appearance test, there were two models which showed bubble, humidity penetration, seal melted frame phenomenon. From this results, the degree of aging under the external environment is a main cause that shortens photovoltaic module life time. So it is considered that the efforts for finding optimum condition of manufacturing process should be needed.

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Interfacial Effects on the Aging of Power Cables (계면특성이 전력케이블 열화에 미치는 영향)

  • Han, Jae-Hong;Yi, Dong-Young;Kim, Sang-Joon
    • Proceedings of the KIEE Conference
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    • 1997.07d
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    • pp.1393-1395
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    • 1997
  • In order to investigate the interfacial effects on the aging of power cables, we analyzed recently failed cables using characterization techniques. In this study, some cables showed a convolution which can cause the concentration of electric field and carbonized impurities at the surface of insulation. Also there is a relation between the degree of cross- linking and volume resistivity. From the hot oil test, the sites of water tree and void coincided with each other.

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Nondestructive Evaluation for Thermally Degraded Co-base Superalloy by Scanning Acoustic Microscope (초음파현미경을 이용한 Co 기 초내열 합금 열화재의 비파괴평가)

  • Kim, Chung-Seok;Song, Jin-Hun;Kwon, Sook-In;Lim, Jea-Seang;Park, Ik-Keun
    • Proceedings of the KSME Conference
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    • 2004.04a
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    • pp.336-341
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    • 2004
  • This research investigates the feasibility of ultrasonic microscope for nondestructive assessment of thermal degradation in artificially aged commercial Co-base superalloy, FSX414. This alloy has been used for high temperature structure applications such as stationary gas turbine blade and nozzle chamber in fossil plant. Microstructural change was found that the fine carbides became coarser and spheroidized in matrix as aging time increased. The leaky surface acoustic wave velocity gradually decreases by a maximum of 4.7% with increasing aging time up to 4,000hours. However, the longitudinal wave velocity has a little change. Also, it has a good correlation between leaky surface acoustic wave velocity and Vickers hardness. Consequently, LSAW can be used to examine the degree of degradation in thermally aged Co-base superalloy.

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Estimation of Thermal Aging Embrittlement of LWR Primary Pressure Boundary Components

  • Kim, Sunki;Kim, Yongsoo
    • Nuclear Engineering and Technology
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    • v.30 no.6
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    • pp.609-616
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    • 1998
  • Cast duplex stainless steels are extensively used for primary pressure boundary components. These components are, however, embrittled due to the precipitation of $\alpha$' phase by spinodal decomposition and other processes when exposed to reactor operating temperature for a design lifetime or life extension conditions. This report presents a procedure for estimating the current condition and the residual life of safety-related stainless steel components by using ANL database and correlations. The database of Charpy impact energy suggests that CF-8M grade is the most susceptible to thermal aging and CF-3 grade is the least. Thus, the integrity of CF-8M alleys may be degraded seriously and the degree of deterioration may exceed acceptance limit after several years of service in the nuclear reactors.

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The Effects of Residential Satisfaction on the Quality of Life of Aging people: Comparison between the Elderly Living in the Community and the Elderly Living in Senior Housings

  • Baik, Ok Mi
    • International Journal of Advanced Culture Technology
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    • v.6 no.4
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    • pp.29-38
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    • 2018
  • The purpose of this study was to analyze the direct and indirect effects of residential satisfaction on the quality of life and to analyze the difference according to the residence type. The subjects of this study were 422 elderly people aged 65 or older residing in two metropolitan municipalities. The data were analyzed by using structural equation model by multi-group analysis. The results showed that the degree of satisfaction with the residential environment indirectly affected not only the quality of life of the elderly but also social participation activities. As a result of verifying the difference of the residential satisfaction and quality of life path according to the residence type, there was a difference in the route between groups according to the type of residence. This study is significant in that the elderly who have not been interested in the elderly housing policy have been investigated and the relationship between the residential satisfaction and quality of life of the elderly by residence type has been investigated .

The Effect of Ausforming Process on Mechanical Properties of Ultrahigh Strength Secondary Hardening Martensitic Steels (극초고강도 이차경화형 마르텐사이트강의 기계적성질에 미치는 오스포밍 공정의 영향)

  • Kim, S.B.;Won, Y.J.;Song, Y.B.;Cho, K.S.
    • Journal of the Korean Society for Heat Treatment
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    • v.34 no.4
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    • pp.179-184
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    • 2021
  • Two types of secondary hardening martensitic steels, 10Co-14Ni and 6Co-5Ni, were produced by vacuum induction melting to investigate the effect of ausforming process on mechanical properties. According to the results of present study, the alloy samples ausformed at low temperature indicated a rather low hardness level in overall aging time despite the refinement of martensite lath width. As the result can closely be related with the presence of primary carbides precipitated within the initial austenite matrix, we confirmed that, in ultrahigh strength secondary hardening martensitic alloy steels, the ausforming process can rather limit the degree of secondary hardening during the subsequent aging treatment.

Family Ties between Aging Parents and Adult Children Living in Separate Households: Social Support from a Social Exchange Perspective (노부모와 별거 성인자녀와의 가족유대: 정서적 지원에 대한 교환이론적 접근)

  • 정기원
    • Korea journal of population studies
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    • v.24 no.1
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    • pp.123-148
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    • 2001
  • This study explores the factors affecting emotional support between aging parents and adult children living in separate households. With a social exchange perspective on intergenerational family relationship as theoretical framework, the effects of aging parents\` demographic characteristics, potential reward resources. and need for care were tested by analyzing data collected from 2.535 persons aged 65 and over in 9,355 sample households of \`National Survey of Living Status and Welfare Needs of the Elders-1998\`. The statistical analysis of 2,205 aging parents with adult children living in seperate households reveals that the aging parents who have potential reward resources are provided more emotional support by their children than the aging parents without resources are. Findings also show that the elders who live in same households with their own children, and need help from other people with instrumental activities of daily living obtain less emotional support from their children living in separate households. The empirical findings of this study support the social exchange perspectives on family ties between aging parents and adult children living in separate households. but only 8.9 per cents of variance in degree of emotional support is explained by the variables included in the model.

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Relation between Leisure Sports' Activities among Older Adults on Activities of Daily Living and Successful Aging (노인의 여가스포츠 활동참가와 일상생활수행능력 및 성공적 노화의 관계)

  • Kim, Kyong-Sik;Lee, Eun-Joo
    • The Journal of the Korea Contents Association
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    • v.10 no.4
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    • pp.424-432
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    • 2010
  • The purpose of this study was to analyse relationship between leisure sports' activities among older adults on activities of daily living and successful aging. For accomplish this purpose of study, the survey questionnaires were used to collect data. This study firstly set up the population as the Korean elderly who were aged over 65 and living at Seoul as of 2009, 300 persons were chosen by sampling. The numbers, used in actual analysis is leisure sports' activities participant 162, non participant 128. total 300. The statistics method utilized in this study for analyzing the collected data were ANCOVA analysis, multiple regression analysis, path analysis. Activities of daily living reliability is $\alpha$=.876 above and successful aging reliability is $\alpha$=.807 above. The conclusions of this study were as being follows. First, according to the experience of in leisure sports' activities of older adults, it was not difference between the activities of daily living. Secondly, the experience of in leisure sports' activities of older adults had positive effect on successful aging. Thirdly, more intensity of in leisure sports' activities of older adults, had positive effect on instrumental activities of daily living. Fourth, more frequency and intensity of in leisure sports' activities of older adults, had positive effect on social successful aging, more frequency and period(time) of participated in leisure sports' activities of older adults, had positive effect on psychological social successful aging. Finally, the degree of in leisure sports' activities of older adults, had direct or indirect positive effect on activities of daily living and successful aging.

Housing Preference According to Social Relations of Urban Elderly in China (중국 도시거주 노인의 사회적 관계에 따른 주거선호연구)

  • Xuhuiyan, Xuhuiyan;Lee, Yeun-Sook;Lim, Yea-Ji
    • Journal of the Korean housing association
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    • v.26 no.3
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    • pp.33-43
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    • 2015
  • According to aging society and social network society, the necessary of suitable alternative housing in the era has been increasing. The purpose of this research is to understand housing preference depended on the social relation of the elderly who lives in Beijing, China. The social relation was comprised of contact degree with child, contact degree with friend, contact degree with relative, degree of community participation, satisfaction with spouse and satisfaction with child. The housing preference was comprised of housing ownership, housing location, housing size and housing type. The survey was conducted on the elderly of 150 above fifties who lived in Beijing, China. For the result, the social relation was associated with the housing preference. Particularly, the relationship between the children was related to the housing ownership, housing location and housing size. The relationship between friends was related to the housing type. The level of community participation was related to the housing location. Social independence of the elderly, family cohesion, community attachment and adaption tendency were correlated with the housing preference. In conclusion, it was empirically identified that the social relation of the elderly had a relation with predicting housing preference. This result is expected to be useful in development of housing for the elderly in the future.