• Journal of the Korean Data and Information Science Society
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• 제14권3호
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• pp.571-578
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• 2003

In this paper, we consider two components system which have bivariate weibull model with bivariate type I censored data. We proposed maximum likelihood estimator and relative frequency estimator for the reliability of series system. Also, we construct approximate confidence intervals for the reliability based on the two proposed estimators. And we present a numerical study.

• Communications for Statistical Applications and Methods
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• 제20권6호
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• pp.467-474
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• 2013

It is common to measure multiple coverage metrics during software testing. Software reliability growth models and coverage growth functions have been applied to each coverage metric to evaluate software reliability; however, analysis results for the individual coverage metrics may conflict with each other. This paper proposes the virtual coverage metric of a normalized first principal component in order to avoid conflicting cases. The use of the virtual coverage metric causes a negligible loss of information.

• Journal of the Korean Data and Information Science Society
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• 제23권4호
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• pp.815-823
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• 2012

In this paper reliability growth model in which the operating time between successive failure is a continuous random variable is proposed. This model is for Burr type XII distribution with two parameters which is discussed in two versions: the order statistics and non-homogeneous Poisson process. The two software reliability measures are obtained. The performance for two versions of the suggested model is tested on real data set by U-plot and Y-plot using Kolmogorov distance.

• 산업경영시스템학회지
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• 제35권4호
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• pp.1-9
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• 2012

Decisions on reliability screening rules and burn-in policies are determined based on the estimated reliability. The variability in a semiconductor manufacturing process does not only causes quality problems but it also makes reliability estimation more complicated. This study investigates the nonuniformity characteristics of integrated circuit reliability according to defect density distribution within a wafer and between wafers then develops optimal burn-in policy based on the estimated reliability. New reliability estimation model based on yield information is developed using a spatial stochastic process. Spatial defect density variation is reflected in the reliability estimation, and the defect densities of each die location are considered as input variables of the burn-in optimization. Reliability screening and optimal burn-in policy subject to the burn-in cost minimization is examined, and numerical experiments are conducted.

• International Journal of Quality Innovation
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• 제5권1호
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• pp.110-121
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• 2004

There is a new trend of incorporating software coverage metrics into software reliability modelling. This paper proposes a coverage-based software reliability growth model. Firstly, the failure rate function in coverage is analytically derived. Then it is shown that the number of detected faults follows a Nonhomogeneous Poisson distribution of which intensity function is the failure rate function in coverage. Practical applicability of the proposed models is examined by illustrative numerical examples.

• 한국신뢰성학회지:신뢰성응용연구
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• 제9권4호
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• pp.303-317
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• 2009

There are a lot of different data in a company. Some of the data can be modified to produce valuable information on reliability. In this study different types of data that can be obtained in a company are reviewed. Reliability related data that can be taken throughout the life cycle of a product are also reviewed. Developing a method of gathering all of the pertinent data from the various sources and databases and pulling them into one central location is explained.

• 한국치위생학회지
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• 제23권6호
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• pp.423-429
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• 2023

Objectives: The study aimed to assess the form, reliability, and quality of information related to periodontal diseases shared on YouTube. Methods: On october 23, 2023, we conducted searches on YouTube using four keywords related to periodontal diseases. The searches retrieved a total of 394 videos from the first five pages for each keyword. Of these, 151 were included in the analysis. Videos were categorized based on the source and usefulness of the information, and their reliability and quality were assessed. Results: Analysis of the information sources revealed that medical websites or TV channels (45.7%) were the most prevalent, whereas commercial websites (2.0%) were the least prevalent. Videos uploaded by physician or hospitals (3.08±0.48) and medical websites or TV channels (3.01±0.94) demonstrated higher reliability. Videos categorized as having good and excellent quality were predominantly from physician or hospital sources (88.2%). Useful information related to periodontal diseases was available in 85.4% of videos, with physician or hospital sources contributing the highest proportion of useful information (52.7%). Conclusions: Videos from physician or hospital sources provide high-quality useful and reliable information. To ensure the provision of more useful and accurate information, the involvement and interest of experts are deemed essential.

• 한국신뢰성학회지:신뢰성응용연구
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• 제15권2호
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• pp.101-107
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• 2015

In this paper, we review the domestic reliability standards and its global counterparts IEC/TC 56 international reliability standards. Recently private transfers of reliability certification control tower has established in Korea. Some check points to consider regarding the control tower transfer process to the non-government organization are suggested. Also the IEC/TC 56 and its relevant reliability standards are introduced. Understanding of the IEC/TC56 system will be helpful for the time of non-government organization control tower transfer in the reliability certificate specification

• 한국통신학회논문지
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• 제42권1호
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• pp.88-97
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• 2017

With the increasing of the penetration rate of large-scale wind farms, a reliable, highly available and cost-effective communication network is needed. As the failure of a WF communication network will significantly impact the control and real-time monitoring of wind turbines, network reliability should be considered into the WF design process. This paper analyzes the network reliability of different WF configurations for the Southwest Offshore project that is located in Korea. The WF consists of 20 WTs with a total capacity of 60 MW. In this paper, the performance is compared according to a variety of indices such as network unavailability, mean downtime and network cost. To increase the network reliability, partial protection and full protection were investigated as strategies that can overcome the impact of a single point of failure. Furthermore, the reliability performances of different network architectures are analyzed, evaluated and compared.

• 대한기계학회논문집A
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• 제36권8호
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• pp.921-927
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• 2012

신뢰성 기반 최적설계는 설계변수들의 변동을 평균이나 분산 등의 통계적 특성으로 고려하여 설계자가 원하는 신뢰도를 만족하는 해를 구한다. 신뢰도를 구하기 위한 기존의 신뢰성해석 기법들은 변수들이 연속함수로 정의되는 특정 확률분포를 따른다는 가정을 하지만 실제 문제에서 변수들은 한정적인 이산정보의 형태인 경우가 많기 때문에 변수들에 대한 가정을 하지 않고 이산정보로부터 신뢰성해석을 수행하는 것은 매우 중요하다. 본 연구에서는 후보 분포들 중에서 이산정보를 가장 잘 추정하는 분포를 결정하는 기법인 Akaike 정보척도를 이용하여 신뢰성해석 및 신뢰성 기반 최적설계를 수행하는 기법을 제안한다. 수학예제를 통해 정확성을 검증하고 철도차량 용접대차의 신뢰성 기반 최적설계에 적용하여 제안한 기법의 유용성을 확인한다.