Tzong-Ru Tsai

Prof. Tzong-Ru Tsai

Department of Statistics, Tamkang University, Tamsui District, New Taipei City 251, Taiwan
orcid

Research Focus & Metrics

Academic Career Length

31Years (1996-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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1 July 2006 in Journal of Applied Statistics
Verified
Journal Article
Closed access
Tzong-Ru TsaiTzong-Ru Tsai
Tzong-Ru Tsai
SWShuo-Jye Wu
Shuo-Jye Wu
This paper considers the problem of an acceptance sampling plan for a truncated life test when the lifetime follows the generalized Rayleigh distribution. For different acceptance numbers, confidence levels, and values of the ratio of the fixed experiment time to the specified mean life, the minimum sample sizes necessary to ensure the specified mean life are found. The operating characteristic values of the sampling plans and producer's risk are discussed. Some tables are presented and the use of the tables is illustrated by a numerical example.

10 November 2009 in Communications in Statistics - Simulation and Computation
Verified
Journal Article
Closed access
YLYuhlong Lio
Yuhlong Lio
Tzong-Ru TsaiTzong-Ru Tsai
Tzong-Ru Tsai
SWShuo-Jye Wu
Shuo-Jye Wu
Time to failure due to fatigue is one of the common quality characteristics in material engineering applications. In this article, acceptance sampling plans are developed for the Birnbaum–Saunders distribution percentiles when the life test is truncated at a pre-specified time. The minimum sample size necessary to ensure the specified life percentile is obtained under a given customer's risk. The operating characteristic values (and curves) of the sampling plans as well as the producer's risk are presented. The R package named spbsq is developed to implement the developed sampling plans. Two examples with real data sets are also given as illustration.

1 June 2011 in Journal of Applied Statistics
Verified
Journal Article
Closed access
YLYuhlong Lio
Yuhlong Lio
Tzong-Ru TsaiTzong-Ru Tsai
Tzong-Ru Tsai
Let X and Y have two-parameter Burr XII distributions. The maximum-likelihood estimator of δ=P(X<Y) is studied under the progressively first failure-censored samples. Three confidence intervals of δ are constructed by using an asymptotic distribution of the maximum-likelihood estimator of δ and two bootstrapping procedures, respectively. Some computational results from intensive simulations are presented. An illustrative example is provided to demonstrate the application of the proposed method.

1 June 2015 in IEEE Transactions on Reliability
Verified
Journal Article
Closed access
Tzong-Ru TsaiTzong-Ru Tsai
Tzong-Ru Tsai
WSWen-Yun Sung
Wen-Yun Sung
YLY. L. Lio
Y. L. Lio
SCShing I. Chang
Shing I. Chang
JLJye-Chyi Lu
Jye-Chyi Lu
An accelerated degradation test (ADT) can be used to assess the reliability of highly reliable products by using degradation information. In this study, to exhibit a monotone increasing pattern, the gamma process is used to model the degradation of a product subject to a constant-stress ADT of two loadings. Maximum likelihood estimates (MLEs) of the parameters of the ADT model were obtained. Given a budget for the total cost, an optimal ADT procedure was established to minimize the asymptotic variance of the MLE of the mean time to failure of a product, and the sample size and termination time of each run of the ADT at a constant measurement frequency were determined. An algorithm is provided to achieve an optimal ADT plan. An extensive Monte Carlo simulation was implemented to evaluate the sensitivity of the MLE variations to the sample size. A lumen degradation data set of light emitting diodes is presented to illustrate the proposed method.

20 April 2010 in Journal of the Chinese Institute of Industrial Engineers
Verified
Journal Article
Closed access
YLY.L. Lio
Y.L. Lio
Tzong-Ru TsaiTzong-Ru Tsai
Tzong-Ru Tsai
SWShuo-Jye Wu
Shuo-Jye Wu
In this article, acceptance sampling plans are developed for the Burr type XII distribution percentiles when the life test is truncated at a pre-specified time. The minimum sample size necessary to ensure the specified life percentile is obtained under a given customer's risk. The operating characteristic values (tables) of the sampling plans as well as producer's risk are presented. The R package named spBurr is developed to implement the sampling plans. Two real datasets regarding the oil breakdown of an insulating fluid under high test voltage and the first failure times of small electric carts used for internal transportation and delivery are given as illustration.

1 January 2009 in European Journal of Operational Research
Verified
Journal Article
Closed access
WLWanbo Lu
Wanbo Lu
Tzong-Ru TsaiTzong-Ru Tsai
Tzong-Ru Tsai