• International Journal of Reliability and Applications
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• 제9권1호
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• pp.53-70
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• 2008

In this paper, we discuss the plethora of uses for the software package R, and focus specifically on its helpful applications in reliability data analyses. Examples are presented; including the R coding protocol, R code, and plots for various statistical as well as reliability analyses. We explore Kaplan-Meier estimates and maximum likelihood estimation for distributions including the Weibull. Finally, we discuss future applications of R, and usages of quantile regression in reliability.

• 품질경영학회지
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• 제45권4호
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• pp.981-994
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• 2017

Purpose: In this study, the reliability growth management procedures for armed vehicle is suggested and an illustrative case study of launcher system is given. Methods: Crow-AMSAA model is adopted to manage reliability growth of armed vehicle using failure data acquired from development test phase to field operation phase. Between the development test phase and the production phase, the suggested reliability growth procedures for armed vehicle entails accelerated life test of the selected module whose design is changed to improve its reliability for assuring the target system reliability. And it can be verified through estimating the system reliability based on the failure data of field operation phase. Results: It is shown that the proposed reliability growth management procedures are effective for armed vehicle based on the case study of launcher system. After estimating the reliability of launcher system at every development test, some items are selected to change their designs for improving reliability. Accelerated life test is performed to prove the reliability improvement and finally it is verified through the field operation. Conclusion: The reliability growth management procedures for armed vehicle is suggested and the case study of launcher system shows it can be effective for managing the reliability growth of the armed vehicle.

• 항공우주기술
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• 제3권2호
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• pp.91-97
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• 2004

본 논문에서는 고신뢰성 발사체개발에 필수적인 체계기술의 하나로 인식되고 있는 신뢰성 관리(Reliability Management)에 대한 기초연구를 수행하였으며, 향후 KSLV 프로그램에 적용될 신뢰성 관리 추진전략을 단계별로 기술하여 제시하였다. 또한 해외 신뢰성 관리 분석을 통하여 KSLV 프로그램의 최종목표인 상용 발사서비스 시장에 진출하기 위해 요구되는 신뢰성 목표수준을 제시하였다.

• International Journal of Reliability and Applications
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• 제8권2호
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• pp.153-173
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• 2007

Wood-plastic composites (WPC) are gaining market share in the building industry because of durability/maintenance advantages of WPC over traditional wood products and because of the removal of chromated copper arsenate (CCA) pressure-treated wood from the market. In order to ensure continued market share growth, WPC manufacturers need greater focus on reliability, quality, and cost. The reliability methods outlined in this paper can be used to improve the quality of WPC and lower manufacturing costs by reducing raw material inputs and minimizing WPC waste. Statistical methods are described for analyzing stiffness (tangent modulus of elasticity: MOE) and flexural strength (modulus of rupture: MOR) test results on sampled WPC panels. Descriptive statistics, graphs, and reliability plots from these test data are presented and interpreted. Sources of variability in the MOE and MOR of WPC are suggested. The methods outlined may directly benefit WPC manufacturers through a better understanding of strength and stiffness measures, which can lead to process improvements and, ultimately, a superior WPC product with improved reliability, thereby creating greater customer satisfaction.

• 한국신뢰성학회지:신뢰성응용연구
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• 제17권3호
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• pp.246-255
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• 2017

Purpose: This study proposes the optimal PM (preventive maintenance) policy of leased equipment for lessee's decision-making using two types of reliability condition. Methods: We consider reliability threshold based PM model. Equipment reliability is estimated and used as condition variable. The effect of repair for maintenance is imperfect and represented by age reduction factor. Results: We provide two PM policies. Policy 1 is focused on minimized total cost. This policy guarantees reliability threshold until last maintenance action. Policy 2 focus on maintaining reliability threshold during leased period. The proposed approach provides optimal reliability threshold under number of PM. Through result, we finally construct decision-making process for lessee using reliability threshold and end of reliability. Conclusion: This study provides two PM policy for lessee's decision-making. Through numerical example, we get a result of optimal reliability threshold, number of PM, optimum alternative under lessee's reliability condition.

• 품질경영학회지
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• 제44권1호
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• pp.29-42
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• 2016

Purpose: This paper reviews the papers on reliability issues which are published in the Journal of the Korean Society for Quality Management (KSQM) since 1965. The literature review is purposed to survey a variety of reliability issues for several categories Methods: We divide all of reliability issues into 9 categories: acceleration test, reliability estimation, system reliability, software reliability, reliability data collection and analysis method, lifetime distribution, maintenance and warranty strategy, reliability applications, and reliability applications to military area Results: Dividing all of papers on reliability published in KSQM for 50 years into 9 categories, we provide a chronological roadmap for individual categories, and summarize the contents and contributions of surveyed papers Conclusion: The review paper is expected to provide future direction to improve reliaiblity theories and applications in manufacturing and service industries

• International Journal of Reliability and Applications
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• 제5권4호
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• pp.147-154
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• 2004

This work developed and algorithm for a set covering model when the reliability of covers is a concern. This model extended the usage of the set covering model.

• 품질경영학회지
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• 제25권4호
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• pp.185-205
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• 1997

Reliability management requires many activities such as conceptual design, detail design, reliability evaluation and analysis, life testing, and environmental screening, etc.. To perform these activities effectively, a lot of information are required : information for failure mechanism, failure modes, part characteristics, and environmental conditions, etc.. These information should be managed to be used effectively and accurately in reliability activities and feedback to product design and manufacturing. This study identified and characterized these information and classified them according to the reliability activities commonly adopted in many manufacturing industries. IDEF1 was used to define and characterize the flow and the relationship of these reliability information and model is proposed which represents the structure of reliability information systems. The proposed model can be used as a basis for developing reliability management softwares.

• 대한안전경영과학회:학술대회논문집
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• 대한안전경영과학회 2004년도 춘계학술대회
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• pp.161-167
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• 2004

IEC 60300 series, the international standards on reliability management system are newly developed and introduced rapidly worldwide. In order to meet this fast-changing situation, it is necessary to apply them to the Korean industries effectively. It includes the establishment of the infrastructure such as documentation of Korean Standards, introduction of test equipments and test manuals, accreditation of the certification body and training of the specialists etc. IEC 60300 is upgraded management system of the ISO 9000 and ISO 14000. In this regard, the Korean companies which was certified with the ISO 9000 or 14000 should endeavor to find new strategies and methods to be certified with ISO 60300. This paper introduces a quantitative method of estimating the level of the reliability management system by applying the MIR(Maturity Index on Reliability) technique. This enables the estimation of the operation level of the system and can upgrade the maturity level of it.

• 대한안전경영과학회:학술대회논문집
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• 대한안전경영과학회 2008년도 추계학술대회
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• pp.611-622
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• 2008

It is hot issue to get the competitiveness of product through reliability-growth as well as availability and safety in almost high-technology industry including military, chemistry, nuclear, telecommunication, transportation service and so on. In advanced countries, worldwide leading companies have tried to improve and develop high-reliability product as well as reliability management system(IEC60300). We investigate reliability certification systems for product and management system. Additionally, we study the feasibility on the adoption of dependability management system(IEC60300) by empirical survey on companies with product-reliability certification(R-mark) in Korea.