• Title/Summary/Keyword: long-life time

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Study on the Prediction of the Life-time in the Macroscopic Solid-Solid Interfaces (고체-고체 거시계면의 수명예측에 관한 연구)

  • 박정규;배덕권;정동회;오재한;김충혁;이준웅
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2000.07a
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    • pp.775-778
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    • 2000
  • In this paper, the life-time of macro interface between Epoxy/EPDM which consists in underground power cable joints is predicted. The electrode system of specimen is designed by FEM(finite elements method). The breakdown strength of specimens are observed by applying high AC voltage at the room temperature. The breakdown times under the constant voltage below the breakdown voltage were gained. As constant voltage is applied, the breakdown time is proportion to the breakdown strength. The life exponent n is gained by inverse power law, and the long breakdown life time can be evaluated.

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Postmenopausal Hormone Replacement Therapy (폐경후 여성호르몬 보충요법)

  • Park, Hyoung-Moo
    • Korean Journal of Psychosomatic Medicine
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    • v.4 no.1
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    • pp.98-108
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    • 1996
  • Korean women are now living almost 1/3 of their life after menopause. Sex-steroid hormone deficiency adversely affect various fields of physical & mental activity and quality of life during this period. Therefore, replacement of deficient hormone is thought to be natural therapeutic modality. Postmenopausal syndrome is recently redefined as an endocrinopathy with both short-and long-term sequelae, as a result of cessation of ovarian function. Hormone replacement therapy taken at or near time of menopause alleviates shot-term acute menopausal symptoms such as vasomotor disturbances and psychological problems. HRT also beneficially affects some of intermediate symptoms such as urogenital atrophy and cutaneous problems. The major benefits of long-term use were reductions in risk of long-term sequelae, that is, total fracture by 50-60%, cardiovascular disease by 50% and cerebrovascular disease by 30-40%, respectively. In addition, HRT may also positively influence Alzheimer's disease, reduce the colorectal cancer risk and increase longevity of the life. In conclusion, all postmenopausal women should consider preventive HRT when there are no contraindications.

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Improvement of Long-term Creep Life Prediction Method of Gr. 91 steel for VHTR Pressure Vessel (초고온가스로 압력용기용 Gr. 91 강의 장시간 크리프 수명 예측 방법 개선)

  • Park, Jae-Young;Kim, Woo-Gon;EKAPUTRA, I.M.W.;Kim, Seon-Jin;Kim, Min-Hwan
    • Transactions of the Korean Society of Pressure Vessels and Piping
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    • v.10 no.1
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    • pp.64-69
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    • 2014
  • Gr. 91 steel is used for the major structural components of Generation-IV reactor systems, such as a very high temperature reactor(VHTR) and sodium-cooled fast reactor(SFR). Since these structures are designed for up to 60 years at elevated temperatures, the prediction of long-term creep life is important for a design application of Gr. 91 steel. In this study, a number of creep rupture data were collected through world-wide literature surveys, and using these data, the long-term creep life was predicted in terms of three methods: the single-C method in Larson-Miller(L-M) parameter, multi-C constant method in the L-M parameter, and a modified method("sinh" equation) in the L-M parameter. The results of the creep-life prediction were compared using the standard deviation of error value, respectively. Modified method proposed by the "sinh" equation revealed better agreement in creep life prediction than the single-C L-M method.

The 'Be Slow'Movement and Its Impact on the Current Fashion (최근 국내외 패션에 나타난 느리게 살기 운동의 영향)

  • 김윤희
    • Journal of the Korean Society of Costume
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    • v.52 no.6
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    • pp.165-179
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    • 2002
  • This paper begins with the thesis that the so-called 'Be Slow' Movement has not only affected the contemporary life style but also the current fashion trend in the West as well as in Korea. The influence of the 'Be Slow' Movement on the everyday life of Western and Korean society can be documented by recent books, news reports, and many articles from various kinds of mass media and fashion magazines since the year 2000. The results of this study can be summarized as follows. First. the 'Be Slow' Movement is a new cultural phenomenon and very different from that of the past century. It has emerged very recently and it could affect the life style o( its followers for a long period of time. Second, the influence of 'Be Slow' Movement on everyday life can be witnessed in many behavioral choices. such as the preference of organic food and natural cooking for food and the preference of rural life and a green patch of land for housing. Some aspects of the way of rearing the children and long-term planning of one's life are also under the influence of 'Be Slow' Movement. In a way. the life style Proposed by the 'Be Slow' Movement is somewhat similar to that of 'Bobos'. Third, the influence of 'Be Slow' Movement on the current fashion trend can be observed in the appreciation of time-consuming labour and increased usage of D.I.Y. clothing. The higher value of fashion goods with handcrafted part or scarce luxury item are good examples of the influence by the 'Be Slow' Movement. One can say that the 'Be Slow' Movement is not retrogression, but a re-creation of time and space to be grateful for one's life. Thus, it is not anti-technology but a commercialism with technology in order to enhance the quality of life and to place people in the center of production and consumption. Consequently, one may say that the 'Be Slow' Movement is a appropriate and affluent way of living.

Establishment of Service Life of Educational Facilities - Focused on the rooftop waterproofing and floor finishing -

  • Lee, KangHee;Chae, ChangU
    • KIEAE Journal
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    • v.14 no.5
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    • pp.5-12
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    • 2014
  • Building has been deteriorated gradually owing to geographic, physical complex and other factors. School living condition has a key role to improve the learning ability, life attitude and qualifications to adopt to social life. Therefore, it is important for school environment to keep the living condition. Repair time and scope of school facilities are required to maintain the function and performance to plan the long term repair. But there are little information about the school maintenance such as repair time and function. In this paper, it aimed at providing the service life to suggest the repair time and scope in the roof-proofing and floor finishing which used the three estimation method in probabilistic approach. The service life has a key role to decide the repair time and to make the plan for the repair maintenance. Results of this study are as follows ; First, the 1st repair time were taken through three methods in probabilistic and deterministic functions to eliminate the estimation bias. Second, the service life is suggested 36 years of an elementary school, 34 years of a middle school and 41 years of a high school. Third, the service life of a floor finishing is 43 years of an elementary, 39 years of a middle school and 41 years of a high school. The above study could not include the detailed information about the materials and repair works. Therefore it needs a further study to reflect the detailed information and to make a repair strategy.

Expansion Strategy of Home Visit Nursing Services of Long-Term Care Insurance (노인장기요양보험 재가방문간호 서비스 개발과 확대 방안)

  • Lim, Ji Young;Kim, Juhang
    • Journal of Korean Academic Society of Home Health Care Nursing
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    • v.27 no.3
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    • pp.241-249
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    • 2020
  • Purpose: This study aimed to investigate possible ways to expand the services of home-visit nursing through a review of the progress, achievements, and obstacles of home-visit nursing; a pilot project of an integrated home-service; the application of the Omaha System; as well as a case analysis of providing home-visit nursing services. Method: An integrated review was conducted using various source materials, including laws, previous studies, and a case analysis. Results: In case analysis of providing visiting nursing service, rehabilitation nursing, end-of-life nursing, and dementia care showed high nursing needs. It was necessary that the various home visit nursing services in the intervention area of the Omaha System, administrative services, case management, and center operation activities were all included in the payment systems of long-term care insurance. Conclusion: In the future, home visit nursing services of long-term care insurance should be reborn in the form of a center for integrated case management in the community, which would set long-term goals until the time of a client's death and encompass the realm of human rights for health, quality of daily life, and a dignity of life.

Creep Life Prediction of Elevated Temperature Materials for Pressure Vessel by ISM (ISM에 의한 압력용기용 고온재료의 크리프 수명예측)

  • Kong, Y.S.;Kim, H.K.;Oh, S.K.;Lim, H.K.
    • Journal of Power System Engineering
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    • v.6 no.2
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    • pp.40-47
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    • 2002
  • In this paper, friction welding optimization for 1Cr0.5Mo-STS304 (${\phi}14\;mm$), AE applications for the weld quality evaluation and the applications of various life prediction methods such as LMP (Larson-Miller Parameter) and ISM (initial strain method) were investigated : The creep behaviors of those steels and the friction welded joints under static load were examined by ISM combined with LMP at 400, 500, 550 and $600^{\circ}C$, and the relationship between these two kinds of phenomena was studied. The real-time predicting equations of elevated-temperature creep life (rupture time) under any creep stress at any elevated-temperature could be developed by LMP and LMP-ISM. It was confirmed that the life prediction equations by LMP and LMP-ISM are effective only up to 102 h and can not be used for long times of 103-106 h, but by ISM it can be used for long times creep prediction of more than 104 h with most reliability.

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Creep Life Prediction by ISM of Elevated Temperature Materials for Pressure Vessel(II) (압력용기용 고온재료의 ISM에 의한 크리프 수명예측(II))

  • 공유식;김헌경;황성필;김일석;오세규
    • Proceedings of the Korea Committee for Ocean Resources and Engineering Conference
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    • 2001.05a
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    • pp.307-313
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    • 2001
  • In this Paper, friction welding optimization for 1Cr0.5Mo-STS304($\Phi$14mm), AE applications for the weld quality evaluation and the applications of various life prediction methods such as LMP(Larson-Miller Parameter) and ISM(initial strain method) were investigated : the creep behaviors of those steels and the friction welded joints under static load were examined by ISM combined with LMP at 400, 500, 550 and $600^{\circ}C$, and the relationship between these two kinds of phenomena was studied. The real-time predicting equations of elevated-temperature creep life(fracture time) under any creep stress at any elevated- temperature could be developed by LMP and LMP-ISM, It was confirmed that the life prediction equations by LMP and LMP-ISM are effective only up to 10$^2$hrs and can not be used for long times of 10$^3$-10$^{6}$ hrs, but by ISM it can be used for long times creep prediction of more than 10$^4$hrs with most reliability.

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Estimation of shelf-life by long-term storage test of Pyungwi-san (평위산 전탕팩의 장기보존 시험에 따른 유통기한 설정)

  • Seo, Chang-Seob;Kim, Jung-Hoon;Lim, Soon-Hee;Shin, Hyeun-Kyoo
    • Herbal Formula Science
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    • v.19 no.1
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    • pp.183-194
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    • 2011
  • Objectives : To estimate the shelf-life by long-term storage test of Pyungwi-san. Methods : Experiments were conducted to evaluate the stability such as the selected physicochemical, heavy metal, microbilogical experiment under an acceleration test and long-term storage test of Pyungwi-san in different storage under room temperature, refrigeration and freezing. Futhermore, HPLC analysis was performed for the determinations of glycyrrhizin in the Pyungwi-san on an Inertsil ODS-3 column(250 mm ${\times}$ 4.6 mm, 5 um) using solvent 35% acetonitrile include 0.05% phosphoric acid at 254 nm. The flow rate was 1.0 mL/min. Results : The significant change was not showed in pH, heavy metal, microbiological, identification test and quantitative analysis based on acceleration test and long-term storage test. Retention time of glycyrrhizin in HPLC chromatogram was about 16.065 min and calibration curve showed good linearity($R^2$ = 0.9999). The contents of glycyrrhizin in acceleration test and long-term storage test were 0.068~0.076 mg/mL and 0.066~0.077 mg/mL, respectively. Shelf-lifes of room temperature, refrigeration and freezing by long-term storage test were predicted 41, 24 and 34 months, respectively. Conclusions : The suggested shelf-life would be helpful on the storage and distribution of herbal medicine.

Remaining Useful Life Prediction for Litium-Ion Batteries Using EMD-CNN-LSTM Hybrid Method (EMD-CNN-LSTM을 이용한 하이브리드 방식의 리튬 이온 배터리 잔여 수명 예측)

  • Lim, Je-Yeong;Kim, Dong-Hwan;Noh, Tae-Won;Lee, Byoung-Kuk
    • The Transactions of the Korean Institute of Power Electronics
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    • v.27 no.1
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    • pp.48-55
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    • 2022
  • This paper proposes a battery remaining useful life (RUL) prediction method using a deep learning-based EMD-CNN-LSTM hybrid method. The proposed method pre-processes capacity data by applying empirical mode decomposition (EMD) and predicts the remaining useful life using CNN-LSTM. CNN-LSTM is a hybrid method that combines convolution neural network (CNN), which analyzes spatial features, and long short term memory (LSTM), which is a deep learning technique that processes time series data analysis. The performance of the proposed remaining useful life prediction method is verified using the battery aging experiment data provided by the NASA Ames Prognostics Center of Excellence and shows higher accuracy than does the conventional method.