• Title/Summary/Keyword: Aging factor

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Aging Coefficient Formula of Reinforced Concrete Members under Axial Compression (축하중을 받는 철근콘크리트 부재의 재령계수식 제안)

  • Yoo, Jae-Wook;Yu, Eun-Jong
    • Journal of Korean Association for Spatial Structures
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    • v.13 no.4
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    • pp.67-74
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    • 2013
  • The Age-adjusted effective Modulus Method(AEMM) is one of the methods adopted for the construction stage analysis of concrete structures. The AEMM uses the aging factor to consider the effects of the varying concrete stress. In the aspects of computation time and the accuracy of the results, the AEMM is considered as one of most appropriate methods for construction stage analysis of tall building structures. Previous researches proposed appropriate values of the aging factor in the forms of graphs or using very simple equations. In this paper, an equation for estimating the aging factor as a function of rebar ratio in the section, compressive strength of concrete, notional member dimension, and age of concrete at the load application. The validity of aging factor proposed in this paper were examined by the comparison with the results of step-by step method.

Accessing Factor Structure and Construct Validity of the Successful Aging Inventory (노인의 성공적 노화 측정도구에 대한 요인 구성타당도 평가)

  • Kim, Eun Joo
    • Journal of Korean Academy of Nursing
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    • v.43 no.4
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    • pp.568-578
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    • 2013
  • Purpose: The purpose of this study was to evaluate the reliability and validity of the Korean version of the Successful Aging Inventory (SAI-K) to determine its suitability for use with older Korean adults. Methods: Exploratory and confirmatory factor analyses were utilized to assess the factor structure and the construct validity of the SAI-K. First- and second-order Confirmatory Factor Analysis (CFA) were conducted to identify the most adequate model. Cronbach's alpha was used to test the reliability. Results: Using a second-order CFA, a four-factor structure was validated (${\chi}^2$=122.82, p<.001, GFI=.92, AGFI=.88, SRMR=.06 RMSEA=.07, 90% CI=.05-.09, CFI=.93). The four-factor SAI-K showed reliable internal consistency with a Cronbach's alpha for the total scale of .86. Conclusion: The four-factor, 13-item SAI-K showed satisfactory reliability and validity and, thus, has the potential to be an appropriate instrument for measuring successful aging in older Korean adults.

The Analysis of Regional Characteristics of the Aging Population in Korea (한국 인구고령화의 지역적 특성 분석)

  • Choi, Jae-Heon
    • Journal of the Economic Geographical Society of Korea
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    • v.16 no.2
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    • pp.233-246
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    • 2013
  • This paper investigates both the spatial patterns of aging population and its formal regional structure in 2010. The results are as follows: first, aging index shows high values in remote mountainous and coastal regions while showing relatively low values in Capital Region and large provincial cities. Aging index has low negative correlation with such variables as population increasing rate, ratio of youth population, ratio of apartments, and ratio of newly built housing. However, aging index shows high positive correlation with variables including ratio of single unit house, ratio of aged peoples' house ownerships, ratio of welfare recipients, ratio of old housing, and number of public healthcare facilities. Secondly, four factors are identified from factor analysis including aging factor, welfare factor, economic vitality factor, and new town factor. The aging level of a region is negatively related to the strong level of those factors. Thirdly, cluster analysis results in four different types of formal regions including rural mountainous coastal type, rural non-capital region type, large metropolitan type, and provincial industrial city type.

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The Structural Relationship among Perceived Environmental Factor, Self-Rated Health and Active Aging for Active Senior Golf Participants (액티브 시니어 골프참여자의 지각된 환경적요인과 주관적 건강 및 활동적 노화의 관계)

  • Kim, Hyung-Jin
    • Journal of the Korean Applied Science and Technology
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    • v.38 no.6
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    • pp.1616-1626
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    • 2021
  • The purpose of this study was to investigate the relationship among perceived environmental factor, active aging and self-rated health for active senior golf participants. The collected data were analyzed using the SPSS 18.0 and AMOS 18.0 programs for Windows. Frequency analysis, confirmatory factor analysis, reliability analysis. After correlation analysis and structural equation model analysis were used. As a results derived through the research are as follows. First perceived environmental factor had a positive effect on active aging. Second, active aging had a positive effect on self-rated health. Third, perceived environmental factor had a positive effect on self-rated health. Fourth, active aging mediated the relationship between perceived environmental factor and self-rated health.

Characteristics of Dissipation Factor in Large Generator Stator Bars (대용량 발전기 고정자 바의 유전정접 특성)

  • Kim, Hee-Dong;Kong, Tae-Sik;Ju, Young-Ho
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2009.06a
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    • pp.402-403
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    • 2009
  • Accelerated aging tests were conducted under laboratory conditions on two generator stator bars. Electrical stress is applied in No. 1 model stator bar. Electrical and thermal stresses are applied in No. 2 model stator bar. As aging times increased from 0 to 11460h, dissipation factor($tan{\delta}$) test was performed on No. 1 and No.2 model stator bars. The ${\Delta}tan{\delta}$ of No. 1 and No. 2 stator bars increased with increased in aging time.

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Assessment Technique and Aging Test for EHV Porcelain Insulators (송전용 자기재 애자의 열화시험 평가기술)

  • Han, S.W.;Cho, H.G.;Park, K.H.;Jung, G.C.;Lee, D.I.;Choi, I.H.;Shin, T.W.
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2002.11a
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    • pp.480-483
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    • 2002
  • This paper through shift norm of insulator and research by accident prevention countermeasure special skill authoritativeness verification of insulator and Long Term aging factor for power transmission analysis and evaluate and prove quality of insulator wish to. Assessment technique by aging of own porcelain insulator observes ageing factor for reciprocity comparison through several examinations. Through cool and heat accelerated Aging test, can measure the leakage current change amount that ensue to each Cycle. Can confirm own blazing fire factor as distribution freshness that ensue in HRB Test's hardness value.

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A Study for Aging Factor of Bulletproof Helmet : High Temperature Treatment (방탄헬멧의 노화인자에 관한 연구 : 고온 환경 처리를 중심으로)

  • Park, Ho Yun;Gu, Seung Hwan
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.21 no.6
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    • pp.332-339
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    • 2020
  • This study was a prior study to establish the shelf life of bulletproof helmets, considered the aging factor of bulletproof helmets. To estimate the aging factor of bulletproof helmets, we established a hypothesis that the 'temperature' factor would have the greatest impact on the shelf life of the bulletproof helmet, considering the environmental treatment of the American army's bulletproof helmet's materials. To verify the hypothesis, high temperature acceleration environmental treatment of bulletproof helmets was performed, and the Arrhenius formula was applied to calculate the shelf life. The study result confirmed the negative correlation between bulletproof performance and high temperature, and the influence of temperature as an aging factor was not significant by deriving life by using the Arrhenius model. The limitation of this study is that we couldn't obtain enough samples due to the specificity (miliary supplies) of the test subjects. However, given that the life-related research on bulletproof helmets has not been carried out, this research has great implications and could be used as a reference for improving the Korean Army's bulletproof helmet specifications.

Parabiosis and Aging Researches (개체병렬결합 그리고 노화 연구)

  • Chung, Kyung Tae
    • Journal of Life Science
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    • v.27 no.12
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    • pp.1515-1522
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    • 2017
  • Most people have a desire to live longer. According to ancient Chinese and Korean mythology, Dongfang Shuo (Dongbang Sahk) lived for 18,000 years. According to a WHO report, the average longevity of humans has extended from 50-odd years in the 1960s to 75-85 years in 2016. Parabiosis, the joining to circulatory systems of two animals, was described as early as the 1860s. It provides a powerful experimental model to investigate the effects of one animal on its partner animal in vivo. Research on reverse aging is an immensely popular in parabiosis studies. In this review, the origin of the parabiosis model and important historical findings based on parabiosis models are presented. Surprising and debated discoveries in aging research are also introduced. Using heterochronic parabiosis of connecting circulatory systems of a young mouse and old mouse, various groups claim to have identified a reverse aging factor, growth differentiation factor 11 (GDF11), which was significantly reduced in blood of old mice. Although the potential existence of any one factor or factors that could reverse aging remains to be confirmed, studies have shown that the parabiosis model is powerful enough to detect reverse aging factors.

Study on Diagnosis for Transformers by Tan $\delta$ and Moisture of Insulation Oil According to Thermal Aging (절연유의 열열화에 따른 Tan $\delta$와 수분의 변화에 의한 변압기의 예방진단 연구)

  • HwangBo, Seung;Han, Min-Koo;Kwak, Hee-Ro;Kim, Jae-Chul
    • Proceedings of the KIEE Conference
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    • 1988.11a
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    • pp.241-245
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    • 1988
  • This paper reports the experiments regarding to diagnosis techniques for power transformers by measuring dissipation factor and moisture contents of mineral oils. Thermal aging environments of mineral oils were varied by the specially designed systems. Thermal aging of elevated temperature of $90^{\circ}C$ was performed for about 240 and 460 hours, respectively. Dissipation factor, permittivity, and water content were measured. Our test samples were not exposed to air. Dissipation factor increased while permittivity did not change. The level of dissipation factor determining the insulating quality of mineral oil was compared with the previous results of resistivity and several correction factor.

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Photo-aging regulation effects of newly bred Green ball apple (신품종 그린볼 사과의 광노화인자 조절효과)

  • Lee, Eun-Ho;Lee, Seung-Yeol;Jung, Hee-Young;Kang, In-Kyu;Ahn, Dong-Hyun;Cho, Young-Je
    • Journal of Applied Biological Chemistry
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    • v.63 no.1
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    • pp.75-82
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    • 2020
  • In this study, extracts from the Green ball apple peel (GBE) and the newly bred green ball apple from Korea showed inhibition effects on photo-aging factor regulation associated with skin aging. To investigate the inhibition effect on photo-aging factor regulation in skin, GBE was treated with UVB to induce photo-aging related factors in CCD986sk fibroblast cells. Photo-aging factor regulation effects showed that GBE inhibited UVB-stimulated matrix metalloproteinase (MMP)-1 and MMP-9 protein synthesis in collagen type I alpha 2 chain (COL1A2), MMP-1, MMP-9, and tissue inhibitors of metalloproteinase (TIMP)-1 protein expression. The expression of COL1A2 and TIMP-1 protein was significantly increased. The mRNA expression levels of COL1A2, MMP-1, MMP-9, hyaluronan synthase (HAS)2, transforming growth factor (TGF)-β, and TIMP-1 were decreased by GBE. The expression of TIMP-1 and TGF-β, which are regulators involved in matrix metalloproteinase and type I procollagen expression, was found to increase with increasing expression of COL1A2. The expression of HAS2, which is involved in the production of hyaluronic acid, one of the structural proteins constituting the skin, was also confirmed. Therefore, GBE showed excellent efficacy against photo-aging factor regulation and could be used as functional material to prevent and treat skin aging.