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研制阶段的成败型产品可靠性Bayes评估 总被引:2,自引:0,他引:2
研究了研制阶段的成败型产品可靠性的Bayes评估问题。针对当前可靠性评估方法中,经典统计方法无法利用历史信息,而传统Bayes方法又存在对历史信息与现场信息不加区分的缺陷,提出了研制阶段成败型产品可靠性评估模型。模型使用混合验前分布,并用历史样本与现场样本的拟合优度来确定混合分布中的继承因子,这样合理性就很容易得到解释。 相似文献
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在加速寿命试验过程中,由于试验设备、观测手段或其他方面的困难可能会造成某些试验数据丢失或未观测到.为解决Weibull分布产品在恒加应力试验中出现的小子样缺失数据情形下的可靠性评估问题,提出了可以综合利用多源信息的Bayes可靠性评估方法.首先通过概率元方法得到缺失数据的似然函数,同时根据似然函数中各未知参数的物理含义确定其验前分布类型,再利用第二类极大似然估计原理得到验前分布中超参数的估计.最后通过仿真实例说明了该评估方法在小子样缺失数据情形下的有效性. 相似文献
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在Weibull分布的定时截尾样本中,对可靠性、可靠寿命和失效率这3种参数的验前分布及形状参数的验前信息进行了分析。论述了结合熵损失函数来求得系统可靠度及寿命的Bayes点估计和置信下限,为大型系统的可靠性评估提供了一种重要的理论依据。 相似文献
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行波管的可靠性对许多军用装备整机系统的正常运行十分重要。但其结构复杂、价格昂贵,如何在小样本条件下提高其可靠性评估的精度是我们目前面临的问题。在此情况下,利用专家经验、历史数据等先验信息来提高其可靠性评估的精度是一个行之有效的途径。本文基于模糊隶属函数给出了一种创建行波管可靠性模糊先验分布的方法,并在此基础上利用Bayes方法实现了行波管先验与试验信息的有效融合。对某卫星用行波管进行可靠性评估的实例表明,采用正态型模糊先验分布的行波管可靠性Bayes评估可以在小样本数和试验结尾程度很高的情况下显著提高可靠性评估的精度,同时Bayes估计可随试验样本信息的增加不断得到修正;而模糊先验分布的带宽可用于调节先验信息在后验分布中所占的比重。 相似文献
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在工程实践中,验前信息往往具有多源性的特点.如何把各类先验信息融合成为现场试验的验前信息就成为一个不可回避的问题.本文针对指数寿命型产品,在考虑其失效率的验前信息可信度时,给出其失效率的Bayes估计方法.通过具体实例说明考虑验前信息可信度时Bayes估计有明显改善. 相似文献
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针对目前大型电子系统任务可靠性评估中,试验样本需求量大,试验费用高、评估时间长,以及评估指标高的特点,提出融合多源验前信息的小样本大型系统Bayes评估法解决这一问题的途径.该方法综合考虑各种因素对大型系统可靠性评估的影响,当试验样本较小时仍能做出准确的估计,最后以某型大型电子系统任务可靠性评估为例,验证了该方法的可行性和有效性. 相似文献
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This paper presents a reliability assessment procedure that systematically combines complete system binomial test data with lower level binomial test data obtained from either partial system or component tests. The procedure uses beta prior distributions of all reliabilities, Bayes theorem, and probability moments. The result is a posterior distribution of system reliability that can be used to determine Bayes point and interval estimates. The beta prior distributions evolve from data on predecessor systems similar to the system in question and engineering knowledge about what the various test-alternatives measure. 相似文献
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Accelerated tests on two similar assemblies suggest that their lifetimes are in excess of 30000 h. A Bayes approach to reliability estimation using life test data from the two assemblies and those from an earlier evaluation of a third assembly, similar to the two under study, is described. The Bayes approach permitted a reduction in the number of test samples, compared to the earlier evaluation. The reliability of the two new assemblies was comparable to or better than that of the older one 相似文献
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The Maximus, bootstrap, and Bayes methods can be useful in calculating lower s-confidence limits on system reliability using binomial component test data. The bootstrap and Bayes methods use Monte Carlo simulation, while the Maximus method is closed-form. The Bayes method is based on noninformative component prior distributions. The three methods are compared by means of Monte Carlo simulation using 20 simple through moderately complex examples. The simulation was generally restricted to the region of high reliability components. Sample coverages and average interval lengths are both used as performance measures. In addition to insights regarding the adequacy and desirability of each method, the comparison reveals the following regions of superior performance: 1. The Maximus method is generally superior for: a) moderate to large series systems of reliable components with small quantities of test data per component, and b) small series systems of repeated components. 2. The bootstrap method is generally superior for highly reliable and redundant systems. 3. The Bayes method is generally superior for: a) moderate to large series systems of reliable components with moderate to large numbers of component tests, and b) small series systems of reliable non-repeated components. 相似文献
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靶场通信系统可靠性验收试验评定方法 总被引:1,自引:1,他引:0
按照经典方法,靶场通信系统可靠性验收试验需要相当长的时间,实现起来难度较大。详述了如何采用Bayes序贯截尾检验方法,在充分利用可信的验前信息条件下,进行通信系统可靠性评定,重点给出了求解验前等效失效数、验前等效试验时间和验前概率的方法,并选定Bayes序贯截尾检验方案进行可靠性判决。Bayes序贯截尾检验方法可大大缩短现场试验时间,对工程实践有一定的指导意义并具有一定的推广价值。 相似文献
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