• Title/Summary/Keyword: Failure factors

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Process Evaluation for Reliability Insurance: An Industrial Case Study

  • Hong, Yeon-Woong
    • Journal of the Korean Data and Information Science Society
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    • v.16 no.2
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    • pp.401-410
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    • 2005
  • In this paper, we calculate the premium rate of reliability insurance policy for brake pads for automobiles using real failure data obtained from use-condition. We try process capability analysis for the manufacturing process of brake-system. We describe the performance factors which have an effect on failure characteristics of brake pads. We also obtain the maximum likelihood estimates of shape and scale parameters of the fitted Weibull distribution for brake pads.

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Reliability Insurance Rate-Making for Wiper Motors

  • Hong, Yeon-Woong;Kwon, Yong-Man
    • Journal of the Korean Data and Information Science Society
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    • v.15 no.1
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    • pp.49-57
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    • 2004
  • In this paper, we calculate the premium rate of reliability insurance policy for wiper motors under the assumption of Weibull physics of failure. We also describe the performance factors which have an effect on failure characteristics of wiper motors. The maximum likelihood estimates of shape parameter and scale parameter are obtained by using interval censored real data of sample sizes 6 using MINITAB.

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Reliability Equivalences of a Series System Consists of n Independent and Non-identical Components

  • Sarhan, A.M.;Mustafa, A.
    • International Journal of Reliability and Applications
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    • v.7 no.2
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    • pp.111-125
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    • 2006
  • This paper introduces different vectors of the reliability equivalence factors of a series system consists of n independent and nonidentical components. The failure rates of the system components are assumed to be constant. The reliability function and mean time to failure are used as performances to derive the reliability equivalences of the system. The results presented here generalize those available in the literatures. Numerical study is given to explain how one can utilize the theoretical results obtained.

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Deriving a Probabilistic Model for Fatigue Life Based on Physical Failure Mechanism

  • Suneung Ahn
    • Journal of Korean Society of Industrial and Systems Engineering
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    • v.24 no.68
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    • pp.1-7
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    • 2001
  • A probabilistic model for fatigue life of a structural component is derived when the component is in a variable-amplitude loading environment. The physical mechanism which governs fatigue failure is used to model the fatigue life. Especially, the judgement of rotational symmetry in the-stress-intensity-factors results in the probability distribution for fatigue life. The probability distribution is related to the familiar truncated Gaussian distribution, which has a single parameter with a direct physical meaning.

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Parts Stresss Analysis for Reliability Prediction of Control Module in Plant (부품부하분석을 이용한 발전소 제어모듈의 신뢰도 예측)

  • 김대웅;강희정
    • Journal of Energy Engineering
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    • v.4 no.3
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    • pp.338-343
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    • 1995
  • The objective of this study is to predict the reliability of the electronic control module at ROD control system in nuclear power plant. Maintaining of the reliability is important issue in the complext system like nuclear plower plant, military equipment, satelite system, etc., because the failure of reliability brings etravagant economic loss and deteriorates public acceptance. In addition to the prediction of reliability, the fators affect the reliability including operating condition, environment, temperature and quality factors were analyzed and simulated. The result shows that the quality factors are more critical for the higher reliability than other two factors.

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Enhancing Implementation Capability of National Maritime Administration for Preventing Marine Pollution

  • Lee Sang-jib
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.2 no.S1
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    • pp.53-73
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    • 1996
  • Almost of all the impediments to enchancing ship safety and preventing vessel-source marine pollution arise from the interaction between direct and indirect factors. The direct factors come from human errores and failure in complince with the international convention standards for the operation of vessels. The indirect factors derive from the will and attitudes of the countries taking little responsibilities with appropriate seriousness for policing their fleets. By focusing in these aspects, this paper intends to propose a new international regime to improve the implementation capability of national maritime administration of each member government of IMO(International Maritime Organization).

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Partial Safety Factors by SOSM/RC Combined Method (제2계 2차모멘트/신뢰성조건 조합방법에 의한 부분안전계수)

  • 이종헌;신현묵;손승요
    • Computational Structural Engineering
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    • v.1 no.1
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    • pp.79-85
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    • 1988
  • The inverse algorithm of Point-Fitted Paraboloid Approximation is derived and used in reliability-based calculations. The algorithm of Reliability- Conditioned method is modified in the calculation of failure points such that nonlinear performance functions can be treated in like manner as linear cases without new formulations. SOSM/RC combined method results in probability of failure closed to specified one, and partial safety factors become nearly constant for a wide range of load ratio.

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FMEA에 의한 기계 부품의 신뢰도 분석

  • 이상진;고장주;강창학;이치우
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 2004.10a
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    • pp.87-91
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    • 2004
  • This paper dealt with FMEA, Which is a method of the analysis to secure safety and confidence coming up to customer's expectation in consideration of the environment of the corporation, the industrial environment, and the functional improvement. And by using FMEA, We showed the example analyzed the confidence of the reduction gear. It was proved by the result of the analysis that the rate of the breakdown which is usually regarded as the first important point to reform can't satisfy the selecting basis to improve. Also the result said that it is not right to depend on only the rate of the failure in making the list of the reform. Through the analysis of the breakdown, FMEA can present the important factors of the reform to improve the confidence of the system. In this study would show the important factors of the improvement in order to product the goods guaranteed confidence through the method of FMEA.

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Probabilistic Considerations on Strengthened Reinforced Concrete Beam for Flexural Loads (휨보강된 철근콘크리트보의 확률론적 고찰)

  • 이차돈;최봉섭;김수정
    • Proceedings of the Korea Concrete Institute Conference
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    • 2001.11a
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    • pp.733-738
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    • 2001
  • Although there are strong needs for evaluating statistical characteristics of strengthened reinforced concrete beams under flexure, many researches have been performed mostly on the mechanical properties and failure mechanisms. Different material properties and resulting reinforcing effect could alter the probabilistic values of the strengthened beams. Existing equations suggested for predicting flexural strengthened reinforced concrete beam with CFRP and steel plate are selected and best-fitting one is used in evaluating probability of failure based on Monte-Carlo method. Influential factors are statistically examined and approximate strength reduction factors are suggested. It was found that the factor is more sensitively influenced by predictive equations as well as characteristics and amounts of strengthening materials.

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Comparison of Reliability Prediction Models for Industrial Tablet PC (산업용 태블릿 PC를 위한 신뢰도 예측 모델 비교)

  • Cho, K.H.;Lee, H.C.;Jang, J.S.;Park, S.C.
    • Journal of Applied Reliability
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    • v.16 no.3
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    • pp.171-179
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    • 2016
  • Purpose: The purpose of this study is to provide a comparison of reliability prediction models between MIL-HDBK-217F and Telcordia SR-332 and to analyze the reliability prediction results. Methods: The reliability of industrial tablet PC was predicted using MIL-HDBK-217F and Telcordia SR-332. To analyze the results, sensitivity analysis was conducted. Results: The reliability of MIL-HDBK-217F was predicted lower than the one of Telcordia SR-332. Considering the factors such as temperature, quality and environment, those provided reliability change of a particular part which highly contribute to the system failure. Conclusion: It is necessary to design the industrial tablet PC that consists of integrated circuits such as microprocessor and memory considering the operating temperature and quality factors.