• 제목/요약/키워드: an aging society

검색결과 2,668건 처리시간 0.03초

室溫時效 및 變形時效가 微小 疲勞크랙의 開口變位에 미치는 影響 (Influence of Room Temperature and Strain Aging on the COD for a Small Fatigue Crack)

  • 김민건
    • 대한기계학회논문집
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    • 제19권2호
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    • pp.402-407
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    • 1995
  • The effects of room temperature and strain aging treatment are discussed on the critical condition for the onset of growth of non-propagating cracks on 0.15% C low carbon steel, with special emphasis on the length of the critical non-propagating crack and on the crack opening displacement(COD) at the crack tip. It is found from the experimental analysis that room temperature and strain aging of a fatigue pre-cracked specimen introduced the closure of a crack tip of the pre-crack and the reduction of crack opening displacement at the wake of crack, together with an improvement in crack growth resistance of the microstructure. This may cause an increase in the endurance limit of the specimen, through the enhancement of effective stress for the onset of growth of the critical non-propagating crack.

AGING ASSESSMENT OF CANDU PLANT MAJOR COMPONENTS

  • Jeong, Il-Seok;Lee, Kyoung-Soo;Kim, Tae-Ryong
    • 한국에너지공학회:학술대회논문집
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    • 한국에너지공학회 2003년도 춘계 학술발표회 논문집
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    • pp.415-423
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    • 2003
  • Korea Electric Power Research Institute(KEPRI) had worked a comprehensive Plant Lifetime Management (PLiM) project for a CANDU plant in corporation with Korea Hydro and Nuclear Power(KHNP). The project had been performed to understand the aging status of major components screened from the plant and to address provisions for the continued operation over its design life. A feasibility of the continued operation was reviewed in the aspects of technology, economics, and regulatory environments. This paper introduces general approach of aging assessment, screening of critical components and an experience of aging assessment for an example of fuel channel that is the most critical component in CANDU plant.

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천연고무받침의 열 노화가 교량 내진성능에 미치는 영향 (Effects of Thermal Aging of Natural Rubber Bearing on Seismic Performance of Bridges)

  • 오주;정희영
    • 대한토목학회논문집
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    • 제33권3호
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    • pp.855-864
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    • 2013
  • 지진격리장치로서 천연고무받침의 동적 특성은 주재료인 고무의 동적거동과 비선형 성질에 의존하고 있다. 역학적이나 환경적인 영향으로 인해 고무재료에 노화가 진행되고 결국에는 손상이 불가피하게 발생하게 된다. 고무재료의 노화에 주원인은 높은 온도에서 반응열로 인한 산화반응으로 알려져다. 이에 따라 천연고무받침에 대한 가속 열 노화실험을 수행하여 열 노화 전 후에 대해 받침의 특성값을 상호 비교하였다. 실험 결과 열 노화 현상은 전단강성과 에너지 감쇠 그리고 등가감소계수에 영향이 있음을 알 수 있었다. 또한 열 노화에 의한 동적특성의 저하를 실제 교량에 적용하여 천연고무받침의 열 노화가 교량의 내진성능에 미치는 영향을 수치해석을 통해 비교분석하였다. 그 결과 천연고무받침에 대하여 열 노화에 따른 기본 특성변화가 교량의 내진성능에 미치는 영향은 크지 않음을 알 수 있었다.

Effect of Aging Process and Time on Physicochemical and Sensory Evaluation of Raw Beef Top Round and Shank Muscles Using an Electronic Tongue

  • Kim, Ji-Han;Kim, Dong-Han;Ji, Da-som;Lee, Hyun-Jin;Yoon, Dong-Kyu;Lee, Chi-Ho
    • 한국축산식품학회지
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    • 제37권6호
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    • pp.823-832
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    • 2017
  • The objective of this study was to determine the effect of aging method (dry or wet) and time (20 d or 40 d) on physical, chemical, and sensory properties of two different muscles (top round and shank) from steers (n=12) using an electronic tongue (ET). Moisture content was not affected by muscle types and aging method (p>0.05). Shear force of dry aged beef was significantly decreased compared to that of wet aged beef. Most fatty acids of dry aged beef were significantly lower than those of wet aged beef. Dry aged shank muscles had more abundant free amino acids than top round muscles. Dry-aging process enhanced tastes such as umami and saltiness compared to wet-aging process according to ET results. Dry-aging process could enhance the instrumental tenderness and umami taste of beef. In addition, the taste of shank muscle was more affected by dry-aging process than that of round muscle.

재난대응조직 연령구성비 변화가 조직효과성 및 서비스질 보장활동에 미치는 영향에 관한 실증분석 - 서울지역 현장활동 소방공무원을 중심으로 - (An empirical study of the impact which the change of age ratio of disaster response organization has on organization effectiveness and quality assurance - Focused on field activities firefighters in Seoul metropolitan city -)

  • 박찬석
    • 대한안전경영과학회지
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    • 제16권4호
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    • pp.133-145
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    • 2014
  • Aging of the fire organizations, typical disaster response agencies also will be in serious problems with aging society. It is expected that the ratio of more than fifties will reach 31~40% after 10~15 years in Seoul fire organization. This Aging of firefighters can bring about a serious problem in disaster and safety management, since firefighters require robust fitness and healthy bodies in disaster situations. In this study, after the analysis of aging status and trend of firefighters in Seoul, I have an empirical analysis about the impact this aging has on organization effectiveness and QA. As a result, the increase of the elderly reduced organization effectiveness and QA. In addition, in the group consisting of less than 50, it is expected to increase the organization's effectiveness and QA activities through field activity to improve the professional skills with age, but could not be confirmed. In the group consisting of more than fifties, it was found that aging had a significant negative impact on organizational effectiveness and QA activities as factors, including physical deterioration by aging.

A study for the countermeasures on Korea's low birth rate and aging society

  • Jung, Myung-Hee
    • 융합경영연구
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    • 제5권4호
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    • pp.1-9
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    • 2017
  • This current study aims to investigate the reason for the low birth rate and increasing aging populations. It aims to offer potential countermeasures and possible solutions that might alleviate the decreasing birth rate and exponentially increasing aging populations. The present research has sought out to uncover the origin of the low birth rates and increasing aging populations by compiling various past studies and statistics in South Korea. It includes additional support from the government for working career women in easing their burden for raising a child and allocating the appropriate funds for the increasing elderly populations. The decreasing birth rate can be contributed as a side effect of the past policies passed in South Korea and in turn created an increase in the aging populations. Policies to tackle this current issue needs to be further investigated and employed for the future of the economic and sociological stability of the society. Consistent efforts need to be made to dispel the continuing decrease for birth rates and alarmingly increasing aging populations. Policies and redistribution of government funds are some of the many things that need to be revised.

기공여방지쇠노적작용(氣功與防止衰老的作用) (Qigong and Anti-aging)

  • ;이경섭;남상수
    • 대한예방한의학회지
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    • 제8권1호
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    • pp.155-161
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    • 2004
  • The average life span is expanded due to the development of modem society, material and cultural life and increasing level of public health. This means that the aging society is rapidly progressing. Geniatric diseases also have increased due to increasing of the aged population. Along with an increase of the aged patient, the anti-aging, prevention of geniatric disease and quality of life is tending high on social concern and medical issues. Many reports showed the evidence to the positive anti-aging effect of Oriental medicine. Qigong therapy, a kind of Oriental medicine, has been used to prevent aging and life prolongation with positive effect for many thousand years. Therefore, qigong practice is popular and common to middle age and old age in China.

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노화에 대한 기대수준이 노인의 건강증진행위에 미치는 영향 (The Association Between Expectations Regarding Aging and Health-Promoting Behaviors Among Korean Older Adults)

  • 김수현
    • 대한간호학회지
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    • 제37권6호
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    • pp.932-940
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    • 2007
  • Purpose: This study was performed to measure expectations regarding aging among community-residing older adults, identify sociodemographic characteristics associated with the level of expectations regarding aging, and examine whether expectations regarding aging were associated with health-promoting behaviors. Methods: Data was collected by using questionnaires of a short version of the Expectations Regarding Aging Survey (ERA-18) and Health Promoting Lifestyle Profile II (HPLP II) from 99 older adults who resided in the community of Kyunggi, Daegu, and Kyungpook province. Results: More than 75% of the participants reported that it was an expected part of aging to have more aches and pains, to become depressed, and to become more forgetful. The mean score of expectations regarding aging was $23.15{\pm}17.80$ (possible range 0-100). The old-old, women, those with less education, less monthly allowance and poor health status had lower expectations regarding aging than other elderly. After controlling for sociodemographic characteristics and perceived health, expectations regarding aging were independently associated with health-promoting behaviors in older adults. Conclusion: The findings demonstrate that older Korean adults have low expectations regarding aging, and expectations regarding aging influence health-promoting behaviors.

Successful Aging Theory (SAT)에 근거한 여성노인의 성공적 노화 예측요인 (Predictors of Successful Aging in Korean Older Women Based on Successful Aging Theory (SAT))

  • 김은주;김영희
    • 여성건강간호학회지
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    • 제17권4호
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    • pp.378-387
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    • 2011
  • Purpose: The purpose of this study was to explore predictors of successful aging in older Korean women based on a recent mid-range nursing theory, the Successful Aging Theory (SAT). Methods: This study utilized a descriptive correlational design. The convenience sample was composed of 174 older women living in the community. Successful aging was measured using the Successful Aging Inventory (SAI). Transcendence was measured using the Self-transcendence Scale (STS). Adaptation was measured using the Coping behavior scale. Stepwise multiple regression was used to identify significant predictors of successful aging. Results: Transcendence, adaptation, and religion were shown to be predictive of successful aging. This regression model explained 56% of the variance in successful aging. The factor with the highest influence was transcendence which explained 52% of the variance. Conclusion: Gerotranscendence-promoting interventions can be an important consideration in caring for older Korean women. Adaptation and spirituality should be included in a holistic aging care.

나노미터 MOSFET 파워 게이팅 구조의 노화 현상 분석 (Analysis of Aging Phenomena in Nanomneter MOSFET Power Gating Structure)

  • 이진경;김경기
    • 센서학회지
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    • 제26권4호
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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.