• Journal of the Korean Data and Information Science Society
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• v.4
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• pp.97-107
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• 1993

In this paper we propose a nonparametric estimator of the men residual life function (MRLF) on a coherent system under the condition that the component lifetimes are censored by system lifetime. It is shown that the proposed estimator, considered as a function of age t, converges weakly to a Gaussian process on a fixed interval. A consistent estimator of asymptotic variance of the proposed estimator is also given.

• Journal of the Korean Data and Information Science Society
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• v.13 no.1
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• pp.147-156
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• 2002

In this paper, we study the properties of the modified winsorized mean to estimate the mean of a two-truncation parameter population. Under some mild conditions, the estimator is found to be strongly consistent and asymptotically unbiased even though the sample is doubly type II censored.

• Journal of the Korean Data and Information Science Society
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• v.9 no.2
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• pp.227-235
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• 1998

In this paper, we consider a hierarchical Bayes estimation of the parameter, the reliability and hazard rate function based on type-II censored samples from a Rayleigh failure model. Bayes calculations can be implemented easily by means of the Gibbs sampler. A numerical study is provided.

• Journal of Applied Reliability
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• v.9 no.1
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• pp.47-58
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• 2009

In this paper, an accelerated life test procedure for a vacuum cleaner motor is proposed. We investigate the failure mechanism of the motor and select some accelerating factors and determine the orifice size as a key accelerating factor. Three stress levels of orifice size are tested and the failure data with censored data are analyzed. The modified accelerating test will reduce the test time in design phase by using the accelerating factor.

• 한국데이터정보과학회:학술대회논문집
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• 2004.04a
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• pp.1-5
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• 2004

In this paper, we calculate the premium rate of reliability insurance policy for T11 composite metreial under the assumption of Weibull physics of failure and Arrhenius law. 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.

• Journal of Korean Society for Quality Management
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• v.25 no.4
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• pp.79-87
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• 1997

In this paper, we obtain maximum likelihood estimator(MLE) of a parallel system reliability for the Marshall and Olkin's bivariate exponential model with birariate type 1 consored data. The asymptotic normal distribution of the estimator is obtained. Also we construct an a, pp.oximate confidence interval for the reliability based on MLE. We present a numerical study for obtaining MLE and a, pp.oximate confidence interval of the reliability.

• Journal of Applied Reliability
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• v.1 no.2
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• pp.139-148
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• 2001

We are concerned in the estimation of lifetime distribution of a component having a few observed failure data and we demonstrate that we can use the maximum likelihood estimation utilizing the censored data when the number of components in use is quite large. Weibull distribution is assumed for the lifetime and a simple estimation procedure is introduced. We also propose the method of determining the optimal number of spares required for a specified period without introducing cost functions. The proposed methods are applied to the photon stop and the water-cooled flange which are major components in Pohang Light Source.

• Proceedings of the Korean Reliability Society Conference
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• 2000.04a
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• pp.201-208
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• 2000

We are concerned in the estimation of lifetime distribution of a component having a few observed failure data and we demonstrate that we can use the maximum likelihood estimation utilizing the censored data when the number of components in use is quite large. Weibull distribution is assumed fur the lifetime and a simple estimation procedure is introduced. We also propose the method of determining the optimal number of spares required for a specified period without introducing cost functions. The proposed methods are applied to the photon stop and the water-cooled flange which are major components in Pohang Light Source.

• Journal of the Korean Data and Information Science Society
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• v.5 no.1
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• pp.59-66
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• 1994

Heller and Simonoff(1990) compared several methods of estimating the regression coefficient in a modified proportional hazards model, when the response variable is subject to censoring. We give another method of estimating the parameters in the model which also allows the dependent variable to be censored and the error distribution to be unspecified. The proposed method differs from that of Miller(1976) and that of Buckely and James(1979). We also obtain the variance estimator of the coefficient estimator and compare that with the Buckely-James Variance estimator studied by Hillis(1993).

• International Journal of Reliability and Applications
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• v.11 no.1
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• pp.23-40
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• 2010

Recently, Zaindin and Sarhan (2009) introduced a new distribution named new generalized Weibull distribution. This paper deals with the problem of estimating the parameters of this distribution in the case where the data is grouped and censored. We use both the maximum likelihood and Bayes techniques. The results obtained are illustrated on a set of real data.