Print Email Facebook Twitter Degradation modeling considering unit-to-unit heterogeneity-A general model and comparative study Title Degradation modeling considering unit-to-unit heterogeneity-A general model and comparative study Author Wang, Zhijie (Shanghai University) Zhai, Qingqing (Shanghai University) Chen, P. (TU Delft Delft Institute of Applied Mathematics; TU Delft Statistics) Department Delft Institute of Applied Mathematics Date 2021 Abstract The performance of units in the same batch can exhibit considerable heterogeneity due to the variation in the raw materials and fluctuation in the manufacturing process. For products suffering performance degradation in their use, such heterogeneity often results in an increase in the dispersion of the degradation paths of units in a population. The degradation rate of products can be unit-specific and often treated as random effects. This paper develops a novel random-effects Wiener process model to account for the unit-to-unit heterogeneity in the degradation, where the generalized inverse Gaussian (GIG) distribution is used to model the unit-specific degradation rate. The GIG distribution is a very general distribution with broad applications, which includes the inverse Gaussian (IG) distribution and the Gamma distribution as special cases. We investigate the model properties and develop an expectation maximization (EM) algorithm for parameter estimation. By comparing the proposed model with existing models on two real degradation datasets of the infrared LEDs and the GaAs lasers, we show that the proposed model is quite effective for degradation modeling with heterogeneous rates. Subject EM algorithmGeneralized inverse Gaussian distributionHeterogeneous degradationWiener process model To reference this document use: http://resolver.tudelft.nl/uuid:48fe8e0c-7a19-42f9-9f69-485c712b3eda DOI https://doi.org/10.1016/j.ress.2021.107897 Embargo date 2022-02-01 ISSN 0951-8320 Source Reliability Engineering & System Safety, 216 Bibliographical note Green Open Access added to TU Delft Institutional Repository ‘You share, we take care!’ – Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public. Part of collection Institutional Repository Document type journal article Rights © 2021 Zhijie Wang, Qingqing Zhai, P. Chen Files PDF 1_s2.0_S0951832021004154_main.pdf 812.13 KB Close viewer /islandora/object/uuid:48fe8e0c-7a19-42f9-9f69-485c712b3eda/datastream/OBJ/view