• 품질경영학회지
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• 제40권3호
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• pp.259-269
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• 2012

Purpose: The purpose of this study was to find out that the statistical method of stockpile reliability of ammunition by items can be applied to the reliability assessment of stockpile ammunition. Methods: We reviewed the statistical method of stockpile reliability of ammunition by items and verified the possibility of its application by case study. Results: We found that the statistical method of stockpile reliability of ammunition by items is very useful and effective to present the reliability of ammunition based on each item and to predict the change of the reliability in the future. The reliability of proximity fuse was about 94.5% and was influenced by manufacture's year and the difference between lot and lot more than storage period. Conclusion: The statistical method of stockpile reliability of ammunition by items can be applied to the reliability assessment of various stockpile ammunitions such as ammunition for mortar and canon.

• 대한기계학회논문집A
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• 제39권12호
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• pp.1305-1311
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• 2015

버터플라이 밸브는 일반적으로 유량을 조절하기 위해 사되는 유량 제어 장치의 일종이다. 본 연구에서는 중심형 버터플라이 밸브의 개선 전후 제품에 대한 신뢰성 시험 데이터의 통계적 분석을 통하여 버터플라이 밸브에 대한 와이블 분포의 형상모수, 특성수명 및 $B_{10}$ 수명을 추정한다. 또한 통계적 가설검정을 이하여 개선 전후 제품의 형상모수와 척도모수에 대한 차이를 검토한다. 가설검정 결과로부터 개선 전후 제품의 형상모수는 유사하며, 척도모수는 증가함을 알 수 있었다. 이러한 분석결과는 향후 신뢰성 인증시험이나 제품에 대한 보증수명 설정에 유한 정보로 활용될 수 있다.

• Communications for Statistical Applications and Methods
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• 제3권3호
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• pp.125-133
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• 1996

In this paper, we present a algebraic technique for computing system reliability for complex system. The method was originally developed as an aid to fault tree analysis but it applies to general problems of reliability assessment. A success expression which directly gives the reliability expression is formed and simplified by the procedure. Several algorithms and examples are illustrated.

• 한국안전학회지
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• 제31권5호
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• pp.95-101
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• 2016

This study proposes a multi-scale dynamic system reliability analysis of control system as a method of quantitative evaluation of its performance in probabilistic terms. In this second paper, we discuss the control effect of the viscous damper on the seismic performance of the structure-level failure. Since the failure of one structural member does not necessarily cause the collapse of the structural system, we need to consider a set of failure scenarios of the structural system and compute the sum of the failure probabilities of the failure scenarios where the statistical dependence between the failure scenarios should be taken into account. Therefore, this computation requires additional system reliability analysis. As a result, the proposed approach takes a hierarchial framework where the failure probability of a structural member is computed using a lower-scale system reliability with the union set of time-sequential member failures and their statistical dependence, and the failure probability of the structural system is again computed using a higher-scale system reliability with the member failure probabilities obtained by the lower-scale system reliability and their statistical dependence. Numerical results demonstrate that the proposed approach can provide an accurate and stable reliability assessment of the control performance of the viscous damper system on the system failure. Also, the parametric study of damper capacity on the seismic performance has been performed to demonstrate the applicability of the proposed approach through the probabilistic assessment of the seismic performance improvement of the damper system.

• 동력기계공학회지
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• 제14권6호
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• pp.61-66
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• 2010

Engineering asset management (EAM) requires the accurate assessment of current and the prediction of future asset health condition. Suitable mathematical models that are capable of predicting time-to-failure and the probability of failure in future time are essential. In general reliability models, lifetime of component and system is estimated using failure time data. This paper deals with the reliability assessment of elevators using life of main components. Especially this work is concerned with the stochastic nature of life of elevator components. First, we investigate the Weibull statistical analysis of lifetime data for the components. The final goal is to establish the mathematical model for reliability assessment. This work provides more perspectives to future research in the fields of reliability and maintainability.

• Asia pacific journal of information systems
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• 제16권3호
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• pp.193-203
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• 2006

Software reliability prediction is a statistical method to put in place a timely software development practice useful for objective assessment of bidders. The current study suggests one research method that enables reliability assessment of such previous projects by studying user satisfaction and project management history. If incorporated into the existing acquisition process, the reliability assessment method will further enhance objectivity and accuracy in bidder selection process. The GQM(Goal Question Metric) paradigm was used to identify assessment metrics for bidder evaluation and questionnaires were collected from users to create user satisfaction indexes. In addition, 'weight of evidence', the most appropriate categorical method, was used to isolate attributes of each variable that may contribute to reliability assessment.

• International Journal of Computer Science & Network Security
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• 제23권9호
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• pp.157-161
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• 2023

Reliability is one of the computable quality features of the software. To assess the reliability the software reliability growth models(SRGMS) are used at different test times based on statistical learning models. In all situations, Tradational time-based SRGMS may not be enough, and such models cannot recognize errors in small and medium sized applications.Numerous traditional reliability measures are used to test software errors during application development and testing. In the software testing and maintenance phase, however, new errors are taken into consideration in real time in order to decide the reliability estimate. In this article, we suggest using the Weibull model as a computational approach to eradicate the problem of software reliability modeling. In the suggested model, a new distribution model is suggested to improve the reliability estimation method. We compute the model developed and stabilize its efficiency with other popular software reliability growth models from the research publication. Our assessment results show that the proposed Model is worthier to S-shaped Yamada, Generalized Poisson, NHPP.

• 한국철도학회논문집
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• 제19권2호
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• pp.187-194
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• 2016

철도교량의 신뢰도 기반 한계상태설계법 도입 시 목표신뢰도지수 산정을 위하여 기존 철도교량의 신뢰도지수 산정이 선행되어야 한다. 대표적인 복선 철도교량 중 하나인 6주형 PSC-I형 거더교량에 대해 신뢰도지수를 산정하였다. 최외측 거더의 휨모멘트에 대한 신뢰도 해석을 수행하였다. 휨저항강도 및 고정하중효과는 도로교 한계상태설계법 도입 시 적용된 선행연구자들의 평균과 변동계수를 활용하였고, 열차의 활하중 효과는 여객/화물 혼용선 중 중량화차 통행이 빈번한 중앙선에서 현장계측 데이터를 활용하였다. 한계상태방정식에 대하여 개선된 일계이차 모멘트법(AFOSM)으로 신뢰도 분석을 수행하였으며, 하중효과와 저항효과의 각 요소가 신뢰도지수에 미치는 민감도를 분석하여 중요도를 검토하였다.

• 산업경영시스템학회지
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• 제36권1호
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• pp.44-52
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• 2013

For evaluating participation in collaboration project, the peer assement method is mostly used and various scoring methods have been proposed. But, the reliability and validity of the peer assessment method are still doubted for all most method. In order to overcome these weaknesss, some guidelines and training methods have been recommended. In this article, however, statistical technique is proposed for measuring individual contributions to collaboration projects considering each assessor's reliability. The gist of our proposed algorithm is that an assessor's reliability depends on the evaluation policy, and this reliability is evaluated by an analysis of variance of the scores assigned by the assessor. We also show that the proposed method is very efficient by case study in university class.

• Nuclear Engineering and Technology
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• 제49권2호
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• pp.349-359
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• 2017

During the past 25 years, in the context of probabilistic safety assessment, efforts have been directed towards establishment of comprehensive pipe failure event databases as a foundation for exploratory research to better understand how to effectively organize a piping reliability analysis task. The focused pipe failure database development efforts have progressed well with the development of piping reliability analysis frameworks that utilize the full body of service experience data, fracture mechanics analysis insights, expert elicitation results that are rolled into an integrated and risk-informed approach to the estimation of piping reliability parameters with full recognition of the embedded uncertainties. The discussion in this paper builds on a major collection of operating experience data (more than 11,000 pipe failure records) and the associated lessons learned from data analysis and data applications spanning three decades. The piping reliability analysis lessons learned have been obtained from the derivation of pipe leak and rupture frequencies for corrosion resistant piping in a raw water environment, loss-of-coolant-accident frequencies given degradation mitigation, high-energy pipe break analysis, moderate-energy pipe break analysis, and numerous plant-specific applications of a statistical piping reliability model framework. Conclusions are presented regarding the feasibility of determining and incorporating aging effects into probabilistic safety assessment models.