• Title/Summary/Keyword: Life analysis

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A Study on the Estimation of Technology Economic Life Using Patent Citation Life Analysis (특허인용 수명분석을 이용한 기술의 경제적 수명 추정에 대한 연구)

  • Sung, Oong-Hyun;Yoo, Sun-Hi
    • Knowledge Management Research
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    • v.8 no.1
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    • pp.49-63
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    • 2007
  • This paper presents a new methodology that allows the influence of technological obsolescence and technology composite competitiveness to estimate technology economic life. In this paper the patent citation life analysis is used to estimate technology representative life, and technology residual life analysis is employed to estimate residual life using the linear and inverse functions. The technology economic life will be determined by combining the estimation results of patent citation life analysis and technology residual life analysis. This paper includes an example of applying it to the US patent data for 5 communications areas. Therefore, this logical concept can be applied usefully to determine the technology economic life and be expected to contribute to obtain credibility of technology valuation.

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A Study on the Prediction of Fatigue Life in Die (금형의 피로수명 예측에 관한 연구)

  • 여은구
    • Journal of the Korean Society of Manufacturing Technology Engineers
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    • v.8 no.4
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    • pp.87-92
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    • 1999
  • Generally the life of die is limited by fatigue fracture or dimensional inaccuracy originated from wear. In this paper to predict the fatigue life of die the stress and strain histories of die can be predicted by the analysis of elastic-plastic finite element method and the elastic analysis of die during the process analysis of workpiece. Also the stress-life curve of die material can be obtained through experiment. With the above to재 facts we propose the analysis method of prediction fatigue life in die,. In the proposed model the analysis of elastic-plastic finite element method for material is carried out by using ABAQUS. Surface force resulted from the contacting border of the die and workpiece is transformed into the nodal force of die to implement elastic analysis. besides the proposed analysis model of die is applied to extrusion die and forging. die.

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The Effects of Stress and Depression on the Quality of Life in Single Elderly Households (고령자 1인 가구의 스트레스와 우울증이 삶의 질에 미치는 영향)

  • Kim, Seok-hwan;Kim, Eun-yeob
    • The Journal of Korean Society for School & Community Health Education
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    • v.19 no.2
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    • pp.43-52
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    • 2018
  • Objects: In this study, we analyzed the correlation between stress and depression related to the quality of life of one elderly household, and analyzed the influence of stress and depression on the quality of life. In this study, I tried to make a plan for improving the quality of life for one elderly. Methods: In this study, the frequency and percentage according to the general characteristics of one elderly household were frequency analyzed. And the mean and standard deviation of stress, depression, quality of life were analyzed on average. And continuous analysis of stress, depression, quality of life, etc., conducted a technical analysis. Relationship to stress, depression, quality of life, correlation analysis was done. The effect of stress and depression on the quality of life was linear regression analysis. SPSS Version 23.0 was used for analysis. Result: Increased stress and increased depression in elderly single households was a static (+) correlation. And the results of the regression analysis showed that the higher the stress and depression of one elderly household, the lower the quality of life. Conclusion: For the improvement of the quality of life of one elderly household, the government should support stress and depression prevention programs according to sex, age, number of chronic diseases.

A Profile Analysis about Thermal Life Data of Electrical insulating materials at Accelerated Life Test

  • Bark, Shim-Kyu
    • Journal of Korea Multimedia Society
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    • v.13 no.12
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    • pp.1814-1819
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    • 2010
  • Since 1987, when statistical analyzing guide for thermal life test of Accelerated Life Test(ALT) was proposed as ANSI/IEEE Std 101, this guide has been used widely for many experiment data. Shim(2004) had done Monte Carlo simulation to compare life of two different systems or materials, based on statistic values obtained from ANSI/IEEE Std 101 data. In this study, a profile analysis is proposed for comparing life of two different systems or materials, and some examples using pre-existing data are given.

The Life Expectancy Making Model for Construction Equipment (건설장비 수명결정 모델)

  • Lee, Yongsu;Kim, Cheol Min
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.32 no.5D
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    • pp.453-461
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    • 2012
  • Life analysis is conducted for economic analysis of equipment or facilities. The purpose of life analysis is to predict future indicators for scrapping construction equipment, and establish and utilize a wide variety of business strategies according to data predictions. First, this study shows the methods to figure out average life, life expectancy and life prediction of construction equipment and the analysis of life making methods, using survival curves. Second, the study proposes and examines the life expectancy making model depending on revenues and expenses. The result of the study reveals that the economic life of the same equipment varies with expenses, revenues and the initial cost. The life expectancy making model for construction equipment reflects respective management status for equipment and will help efficient management for companies.

Development and Validation of Life Safety Awareness Scale of High School Students and Analysis of Interindividual Differences

  • Lee, Soon-Beom;Kim, Eun-Mi;Kong, Ha-Sung
    • International journal of advanced smart convergence
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    • v.11 no.4
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    • pp.104-119
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    • 2022
  • Life safety awareness level diagnosis is necessary for customized safety education and continuous safety awareness. As the starting stage of safety education for each life cycle, a scale that has verified the reliability and validity of high school students' life safety awareness has not yet been developed. In this context, the purpose of this study is to develop and validate the life safety awareness scale of high school students and to analyze interindividual differences. Questionnaire data was collected from April to June 2022 from 834 students in the first, second, and third grades of high schools in △△ city in Jeollabuk-do. A final 25-item scale was developed using the preliminary survey, preliminary test, the main test, descriptive statistical analysis, and exploratory and confirmatory factor analysis. This scale consists of four sub-factors: 'safety prevention', 'safety knowledge', 'safety preparation', and 'safety protection'. Good reliability and validity were verified by analysis of content validity and construct validity. The generalizability of the scale was verified by crossover validation between the search group and the crossover group. Based on the interindividual differences analysis, although there was a difference between genders in life safety awareness, there was no difference by grade level and academic achievement. This study is significant in developing the first valid scale that can measure high school students' life safety awareness and providing the necessity and rationale for life safety education by life cycle considering individual gender differences.

Relationship between among personality type, resilience, and the college life of dental technology students (치기공과 학생의 성격과 회복탄력성 및 대학생활 적응 관계)

  • Ju-Young Choi;Wol Kang
    • Journal of Technologic Dentistry
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    • v.45 no.4
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    • pp.102-110
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    • 2023
  • Purpose: This study aims to examine the influence of personality types on recovery resilience and college life adjustment among dental technology students. Methods: The study recruited 165 students in colleges in some areas using convenience sampling. Data were processed through reliability analysis, frequency analysis, descriptive statistics, and correlation analysis. Moreover, linear regression analysis was performed to confirm the influence. Results: The results confirmed that the motivation for selecting a department exerted an effect on adaptation to college life and satisfaction with majors (p<0.05). Additionally, the finding indicated that personality type partially influenced resilience and adaptation to college life among dental technology students (p<0.05). Finally, the results of regression analysis on adaptation to college life found that resilience and satisfaction with majors were significant predictors of adaptation to college life (p<0.05). Conclusion: To improve adaptation to college life, increasing resilience and satisfaction with majors is necessary.

A Study on Life Estimation of a Forging Die (단조 금형의 수명 평가에 관한 연구)

  • Choi, C.H.;Kim, Y.J.
    • Transactions of Materials Processing
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    • v.16 no.6
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    • pp.479-487
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    • 2007
  • Die life is generally estimated taking failure life and wear amount into consideration. In this study, the forging die life was investigated considering both of these two factors. The fatigue life prediction for the die was performed using the stress-life method, i.e. Goodman's and Gerber's equations. The Archard's wear model was used in the wear life simulation. These die life prediction techniques were applied to the die used in the forging process of the socket ball joint of a transportation system. A rigid-plastic finite element analysis for the die forging process of the socket ball was carried out and also the elastic stress analysis for the die set was performed in order to get basic data for the die fatigue life prediction. The wear volume of the die was measured using a 3-dimensional measurement apparatus. The simulation results were relatively in good agreement with the experimental measurements.

A Study on Optimal Spot-weld Layout Design of the Shock Tower Structure Considering Fatigue Life under Random Vibration Load (불규칙 진동하중을 받는 쇽 타워의 피로수명을 고려한 점용접 위치 최적설계)

  • Lee, Yong-Hoon;Lee, Seung-Yoon;Bae, Bok-Soo;Yim, Hong-Jae
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2011.04a
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    • pp.538-543
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    • 2011
  • In this paper, optimal spot weld layout design of the shock tower structure is performed for increasing fatigue life of spot weld and fatigue life of shock tower simultaneously. To predict the fatigue life, linear static analysis is conducted then fatigue analysis is performed by applying random vibration load. To optimize the spot weld layout, design variables that have an effect on spot weld fatigue life are selected. Based on the DOE table, spot weld fatigue analysis is conducted. Finally, response surface model is made from fatigue analysis results and optimized spot weld layout model which increases fatigue life of sport weld and fatigue life of shock tower is determined.

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A Study on the Prediction of Fatigue Life in Dissimilar Materials Die Considering the Heat Shrink Fit (열박음을 고려한 이종재 금형의 피로수명 예측에 관한 연구)

  • 여은구;김엽래
    • Proceedings of the Korean Society of Machine Tool Engineers Conference
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    • 1999.05a
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    • pp.93-98
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    • 1999
  • Generally, the - life of die is limited by fatigue fracture or dimensional inaccuracy originated from wear. In this paper, to predict the fatigue life of the dissimilar materials die, the stress and stxain histories of die can be predicted by the analysis of elasto-plastic finite element neth hod and the elastic analysis of die during the process analysis of workpiece. Using heat shrink fit analysis, initial stress of the k r t die is computed. Also, the stress-life curve of die material can be obtained through experiment. With the above two facts, we propose the analysis method of predicting fatigue life in die. In the proposed model, tlz analysis of elastic-plastic finite element method for material is carried out by using ABAQUS. Surface force resulted from the contacting border of the die and workpiece is tmnsformed into the nodal force of die to implement elastic analysis. Besides, the proposed analysis model of die is applied to the one material and the dissimilar materials extrusion die.

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