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This paper proposes and illustrates a new perturbed gamma degradation process where the measurement error is modeled as a non‐Gaussian random variable that depends stochastically on the actual degradation level. The expression of the likelihood function for a generic set of noisy degradation measurements is derived, and the expression of the remaining useful life distribution of a degrading unit that fails when its degradation level exceeds a given threshold limit is formulated. A particle filter method is suggested, which allows one to compute the likelihood function and to estimate the remaining useful life distribution in a quick yet efficient manner. In addition, a closed‐form approximation of the perturbed gamma process is proposed to use in the special, yet meaningful, case where the standard deviation of the measurement error depends linearly on the actual degradation level. Finally, an applicative example is discussed, where the parameters of the perturbed gamma process, the remaining useful life distribution, and the mean remaining useful life of the degrading units are estimated from a set of noisy real degradation data. 相似文献
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文章对二次分布无失效数据的可靠度,在先验分布为Beta分布时,给出了可靠度的多层Bayes估计。最后,结合实际问题进行了计算。 相似文献
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对无失效数据的研究 ,是近些年来遇到的一个新问题 ,在实际问题中迫切需要解决 ,这项工作具有理论和实际应用价值 .本文对无失效数据 (ti,ni) ,在时刻ti 的失效概率pi=p{T 相似文献
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《Integral Transforms and Special Functions》2012,23(2):81-94
Identical units of exponential failure time distribution are subjected to accelerated life tests under different inter-related random environments. In a Bayesian setting, we investigate the asymptotic properties of the posterior moments of the unit failure rate, and we also study the asymptotic properties of the predictive mean of the unit lifetime. Then, we examine the Laplace transform of failure rate posterior distribution. The use of the developed methodology is demonstrated by an application. 相似文献
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无失效数据的Bayes和多层Bayes分析 总被引:3,自引:0,他引:3
本文推广了文献[6]的结果,对指数分布无失效数据的失效率,给出了Bayes估计、Bayes置信上限以及多层Bayes估计,从而可以得到无失效数据可靠度的估计,最后,结合实际问题进行了计算。 相似文献
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In this paper, we consider a latent Markov process governing the intensity rate of a Poisson process model for software failures. The latent process enables us to infer performance of the debugging operations over time and allows us to deal with the imperfect debugging scenario. We develop the Bayesian inference for the model and also introduce a method to infer the unknown dimension of the Markov process. We illustrate the implementation of our model and the Bayesian approach by using actual software failure data. 相似文献
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为解决长寿命卫星动量轮可靠性评估无失效数据问题,研究基于性能退化的动量轮可靠性建模与评估方法.首先通过失效分析,提出以温度作为动量轮可靠性的特征量.然后利用动量轮温度的遥测数据,建立其温度随时间变化的叠合模型.为解决动量轮试验样本量不足问题,采用Bootstrap仿真方法建立动量轮寿命分布模型,评估其可靠性水平.实例表明,方法能够在无失效数据情况下,利用性能退化数据评估动量轮可靠性,且具有较高精度,为解决无失效数据条件下长寿命卫星动量轮可靠性建模与评估问题提供了一条有效途径. 相似文献
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无失效数据的贝叶斯统计分析 总被引:1,自引:0,他引:1
本给出一类先验分布下基于失效数据的失效概率的贝叶斯和多层贝叶斯估计,证明了保序性,最后对一个无失效数据的应用例子进行了可靠性统计分析。 相似文献
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Step‐stress accelerated degradation testing (SSADT) has become a common approach to predicting lifetime for highly reliable products that are unlikely to fail in a reasonable time under use conditions or even elevated stress conditions. In literature, the planning of SSADT has been widely investigated for stochastic degradation processes, such as Wiener processes and gamma processes. In this paper, we model the optimal SSADT planning problem from a Bayesian perspective and optimize test plans by determining both stress levels and the allocation of inspections. Large‐sample approximation is used to derive the asymptotic Bayesian utility functions under 3 planning criteria. A revisited LED lamp example is presented to illustrate our method. The comparison with optimal plans from previous studies demonstrates the necessity of considering the stress levels and inspection allocations simultaneously. 相似文献
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We analyze the reliability of NASA composite pressure vessels by using a new Bayesian semiparametric model. The data set consists of lifetimes of pressure vessels, wrapped with a Kevlar fiber, grouped by spool, subject to different stress levels; 10% of the data are right censored. The model that we consider is a regression on the log‐scale for the lifetimes, with fixed (stress) and random (spool) effects. The prior of the spool parameters is nonparametric, namely they are a sample from a normalized generalized gamma process, which encompasses the well‐known Dirichlet process. The nonparametric prior is assumed to robustify inferences to misspecification of the parametric prior. Here, this choice of likelihood and prior yields a new Bayesian model in reliability analysis. Via a Bayesian hierarchical approach, it is easy to analyze the reliability of the Kevlar fiber by predicting quantiles of the failure time when a new spool is selected at random from the population of spools. Moreover, for comparative purposes, we review the most interesting frequentist and Bayesian models analyzing this data set. Our credibility intervals of the quantiles of interest for a new random spool are narrower than those derived by previous Bayesian parametric literature, although the predictive goodness‐of‐fit performances are similar. Finally, as an original feature of our model, by means of the discreteness of the random‐effects distribution, we are able to cluster the spools into three different groups. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
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基于改进的Cholesky分解,研究分析了纵向数据下半参数联合均值协方差模型的贝叶斯估计和贝叶斯统计诊断,其中非参数部分采用B样条逼近.主要通过应用Gibbs抽样和Metropolis-Hastings算法相结合的混合算法获得模型中未知参数的贝叶斯估计和贝叶斯数据删除影响诊断统计量.并利用诊断统计量的大小来识别数据的异常点.模拟研究和实例分析都表明提出的贝叶斯估计和诊断方法是可行有效的. 相似文献
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本文考虑如下纵向数据半参数回归模型:y_(ij)=x′_(ij)β+g(x_(ij))+e_(ij).结合最小二乘法和非参数权函数估计方法得到模型中参数β,回归函数g(·)的估计,并在适当条件下证明了估计量的强相合性. 相似文献
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考虑纵向数据下半参数回归模型:yij=x′ijβ+g(tij)+eij,i=1,…,n,j=1,…,mi.基于最小二乘法和一般的非参数权函数方法给出了模型中参数β和回归函数g(·)的估计,并在适当条件下证明了参数分量β的估计量的强收敛速度和未知函数g(·)的估计量的一致强收敛速度. 相似文献
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失效率的E-Bayes估计和多层Bayes估计 总被引:2,自引:0,他引:2
韩明 《高校应用数学学报(A辑)》2008,23(4)
提出了一种可靠性参数的估计方法—E-Bayes估计法,对寿命服从指数分布的产品,在无失效数据情形,给出了失效率的E-Bayes估计的定义、E-Bayes估计和多层Bayes估计,并在此基础上给出了E-Bayes估计的性质.最后,结合发动机的实际问题进行了计算,结果表明E-Bayes估计法可行且便于应用. 相似文献
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We extend and generalize to the multivariate set-up our earlier investigations related to expected remaining life functions and general hazard measures including representations and stability theorems for arbitrary probability distributions in terms of these concepts. (The univariate case is discussed in detail in Kotz and Shanbhag, Advan. Appl. Probab. 12 (1980), 903–921.) 相似文献