• 제목/요약/키워드: Life evaluation

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가속시험을 통한 불규칙하중을 받는 실구조물의 피로수명평가 (Fatigue Life Evaluation of an Actual Structure under the Irregular Loading using an Acceleration Test)

  • 김형익;배봉국;박재실;석창성;모진용
    • 한국정밀공학회:학술대회논문집
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    • 한국정밀공학회 2004년도 추계학술대회 논문집
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    • pp.166-169
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    • 2004
  • A fatigue test was used to evaluate the fatigue life of an actual structure. The loaded state and the constraint condition of an actual structure must be same as the specimen in order to apply the test results to an actual structure by the specimen. The loaded state and constraint conditions can't be same as the specimen in the actual structure which is complicated. In order to reduce these differences, an actual structure test with a lot of frequencies is need to get a fatigue life curve. Therefore, ten sets of accelerated test units which attached unbalanced mass were composed in this study. Acceleration history about the vibration of an actual structure was acquired. Rainflow counting was used on acceleration history, and the life curve return formula was assumed. The return formula that damage satisfied `1' was acquired in a feedback process by the Miner's rule, which was the linear cumulative damage theory. A conservative fatigue life curve was determined with a return formula to have been presumed by each set. The fatigue life of regular rpm condition was calculated by these conservative fatigue life curves.

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Symptom Frequency of Children with Cancer and Parent Quality of Life in Turkey

  • Kudubes, Asli Akdeniz;Bektas, Murat;Ugur, Ozlem
    • Asian Pacific Journal of Cancer Prevention
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    • 제15권8호
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    • pp.3487-3493
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    • 2014
  • Background: This research was planned with the aim of determining the effect of symptom frequency of children with cancer on the quality of life of their parents. Materials and Methods: In gathering the research data, the Child and Parent Information Form, the Symptom Evaluation Form and the Family Version of Life Quality Scale in Cancer Patients were used. Evaluation was made by using percentage calculations, Kruskal Wallis test, Bonferroni adjusted t-test and Bonferroni adjusted Mann-Whitney U test. The significance level was accepted as 0.005. Results: Some 37.6% of the participant children were female and 62.4% were male, with an average age of $10.2{\pm}4.5$. While 41.0% were newly diagnosed, 46.2% were in remission and 12.8% was in relapse. Highly significant differences were detected according to the symptom frequency with parent physical and psychological health, social anxiety, and spiritual wellness sub-dimensions, as well as total point averages. Conclusions: It is thought that following up the symptoms that might develop depending on cancer diagnosis and treatment and implementing nursing initiatives aimed at reducing the symptoms, knowing the importance of life quality, maintaining measures aimed at life quality and planning initiatives to increase the life quality will play a key role in maintaining and developing the health of Turkish paediatric oncology patients and their parents.

진동 특성을 고려한 자동차 냉각모듈 방진고무의 내구성 평가 (Evaluation for Fatigue Life of Rubber Isolator for Vibration Characteristic on Automotive Cooling Module)

  • 심희진;김한철;김정규
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2008년도 추계학술대회A
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    • pp.350-355
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    • 2008
  • A Rubber mount is widely used for mechanical parts or engineering materials. Especially, it plays an important role in reducing mechanical vibration due to cyclic loading. But, rubber mount is damaged due to the cyclic loading and resonance. Therefore, it is necessary to investigate evaluation of fatigue life considering vibration characteristics for rubber. In this study, a vibration fatigue analysis was performed and based on Power Spectral Density(PSD) and the stress-life curve and a result of frequency response analysis in the finite element method. The measured load history in experiment was transformed to PSD curve. The stress-life curve was obtained by nonlinear static analysis and fatigue test. In addition, frequency response analysis was conducted for mechanical part. In order to evaluate fatigue life of rubber mount, vibration fatigue test was conducted at the constant acceleration-level as well. Fatigue life was determined when the load capacity is reduced to 60% of its initial value. As a result, predicted fatigue life of rubber mount agreed fairly well with the experimental fatigue life.

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한국과 중국의 건축물 전과정 탄소배출량 평가 비교분석에 관한 연구 (A Study on the Comparative Analysis of Building Life Cycle Carbon Emission Assessment in Korea and China)

  • 정붕비;태성호;임효진;김현숙
    • 한국건축시공학회:학술대회논문집
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    • 한국건축시공학회 2023년도 봄 학술논문 발표대회
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    • pp.155-156
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    • 2023
  • This study aims to analyze the factors that cause differences in the evaluation results of the life cycle carbon emissions assessment of buildings in both Korea and China as part of the methodology research of building life cycle assessment for Chinese buildings to promote building life cycle assessment in China. Specifically, it examines the building LCA standards of Korea and the standard for building carbon emission calculation in China as mentioned in the green building certification systems of both countries. Based on the investigation of the two standards, the life cycle carbon emissions of the evaluation target building were evaluated using the building life cycle assessment methods of both countries, and the influencing factors that cause differences in the life cycle carbon emission assessment results of the two countries were analyzed.

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수명이 서로 다른 투자 대안의 평가 (Evaluation of Investment Alternatives with Different Life Times)

  • 박홍석
    • 산업경영시스템학회지
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    • 제14권24호
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    • pp.105-109
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    • 1991
  • In the comparative study of investment alternatives with different life times. It is wrong to compare a long-life time alternative with different life times. It is to wrong to compare a long-life time alternative with a short-life time one by the same measure; therefore, a measure is needed which is suitable for the characters of alternatives. The purpose of this study is in present a method to evaluate investment alternatives with different life times and to explain the assumptions and calculating method.

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경북지역 대학생의 전통음식에 대한 태도(I) -전통음식에 대한 평가, 이용도 및 라이프 스타일과의 관계- (Attitudes of the university students in the Kyung-book area on the traditional foods(I) -The evaluation, the utilization and the life style-)

  • 김성미
    • 한국식품조리과학회지
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    • 제16권1호
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    • pp.27-35
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    • 2000
  • This study intended to find out what the male and female university students in Kyung-book area think about Korean traditional foods, how much they use them, and how their life styles affect their estimates on traditional foods. They evaluated the aspects of traditional foods highly in the order of nutrition(6.07), taste(5.96), appearance(5.40), color(5.33), preservation after cooking(4.82), cost(4.63), and cooking method(4.43). Female students had higher estimates on traditional foods than male students. There was no significant difference in the evaluation between the students raised in rural and urban areas if they had the same educational level. Regardless of gender, Kimchi was most preferred followed by boiled rice, pot stew, grilled fish, and beef out of 25 traditional foods. In the correlation among the evaluation factors and uses of traditional foods, those with high evaluation on traditional foods(r=0.282, p<0.01) and the families with higher income(r=0.316, p<0.01) made more use of traditional foods. For the life style, leisure-valuing type was the greatest part(39.4%) in male students and altruistic type(31.9%) in female students. The altruistic type comprised of the greatest part(34.8%) among the students raised in urban areas and the leisure-valuing type(40.0%) among those raised in rural areas. The altruistic type students put high values on taste, nutrition, appearance, color, and preservation after cooking of the traditional foods. The egocentric type gave high values on cost and cooking method. However, there were no significant differences among the types in every item. The altruistic type put the highest and the leisure-valuing type put the lowest value on traditional foods, respectively, however, it was not significantly different. The individuality-centered type made the most use of traditional foods, whereas the leisure-valuing type made the least(p<0.05).

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원형 노치 CT 시편을 이용한 다양한 피로수명평가 절차의 보수성 평가 (Investigation into Conservatism of Various Fatigue Life Evaluation Procedures Using Round-Notched CT Specimens)

  • 강주연;장동주;김준영;김상언;이종민;허남수;김종성;김진원;김윤재;김대수
    • 한국압력기기공학회 논문집
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    • 제15권2호
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    • pp.19-30
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    • 2019
  • In this study, to evaluate conservatism of various fatigue life evaluation procedures, fatigue tests were conducted using compact tension (CT) specimens with a round notch, made of A516 Gr.70 carbon steel and A240 TP304 stainless steel, under load-controlled cyclic condition. Experimental fatigue failure cycles were measured and compared with predicted fatigue lives using two different life evaluation methods; (1) Design-By-Analysis (DBA) procedure given in ASME B&PV Code, Sec. III, Div. 1, Subsec. NB-3200 and (2) structural stress-based approach provided in ASME B&PV Code, Sec. VIII, Div. 2, Part 5. To predict fatigue failure cycles, three-dimensional elastic finite element analysis was conducted. Fatigue lives were predicted by both design fatigue curve given in ASME B&PV Code, Sec. III, Div. 1, Appendices and best-fit fatigue curve suggested in NUREG/CR-6815 for the DBA procedure. Finally, fatigue lives evaluated by various methods were compared with test results, and then conservatism between each evaluation procedure was discussed.

취약지역 생활여건 개조사업 대상지 선정 평가지표의 적정성 분석 (Analysis of Adequacy of Evaluation Indicators for Selection of Project sites for Living Conditions Renovation Projects in Vulnerable Residential Areas)

  • 최영완;엄민호;김영주
    • 농촌계획
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    • 제29권4호
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    • pp.105-116
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    • 2023
  • In this study, evaluation indicators for quantitative and qualitative indicators were presented by resetting the evaluation indicators for the selection of the living conditions renovation project for vulnerable residential areas by reflecting the results of expert importance. The appropriateness of the project selection evaluation index was reviewed by comparing the results of the expert AHP importance survey to make the project sustainable and to discover vulnerable villages. Evaluation items were constructed based on the guidelines for selecting the target site, and AHP importance evaluation was performed using this evaluation item as a proxy variable. Based on the data collected from 152 villages in Gimhae-si for case studies, the evaluation results were derived by applying the existing guideline evaluation indicators and evaluation indicators reflecting the importance proposed in this study. As a result of the study, Overall, there was a positive correlation between the results of the existing guideline evaluation and the results of the AHP importance survey, but in detail, there is a difference in the results evaluated by the two evaluation methods. In the future, if the scope of participating experts is expanded to supplement the importance evaluation, and the evaluation grade is set by analyzing quantitative data from Gyeongsangnam-do or rural areas nationwide, local governments and others will use this evaluation index as basic data when promoting the project.