首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 15 毫秒
1.
高可靠性产品的可靠性试验很难获得样品失效的数据,可靠性参数估计涉及无失效数据分析,Bayes方法是处理无失效数据分析的有力方法。多层Bayes参数估计涉及到Beta函数比的积分。利用Gamma函数比不等式,导出Beta函数比不等式及Beta函数比的积分不等式,证明了无失效数据下失效概率的EBayes估计与多层Bayes估计渐近相等,且给出多层Bayes估计值小于EBayes估计值的一个充分条件。  相似文献   

2.
The proposed new approach to the procedure for measuring the flow rate and volume of gas under standard conditions in gas distribution organizations increases the reliability of the measurements. It is based on identical transformations of the Clapeyron-Mendeveleev equation, with modifications, and takes into account the composition of the natural gas and the recommendations of Federal Law No. 69-FZ (article 19) of March 31, 1999, about natural gas certification by Gosstandart of the Russian Federation. Use of the modified Clapeyron–Mendeleev equation is shown to changes the form of the transformation functions of various primary measuring transducers (turbine, rotary, vortex, ultrasonic, etc.) under the conditions of actual measurements.  相似文献   

3.
This paper undertakes a reliability study using a Bayesian survival analysis framework to explore the impact of a locomotive wheel's installed position on its service lifetime and to predict its reliability characteristics. The Bayesian Exponential Regression Model, Bayesian Weibull Regression Model and Bayesian Log‐normal Regression Model are used to analyze the lifetime of locomotive wheels using degradation data and taking into account the position of the wheel. This position is described by three different discrete covariates: the bogie, the axle and the side of the locomotive where the wheel is mounted. The goal is to determine reliability, failure distribution and optimal maintenance strategies for the wheel. The results show that: (i) under specified assumptions and a given topography, the position of the locomotive wheel could influence its reliability and lifetime; (ii) the Bayesian Log‐normal Regression Model is a useful tool. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   

4.
The Bayesian network (BN) is an efficient tool for probabilistic modeling and causal inference, and it has gained considerable attentions in the field of reliability assessment. The common cause failure (CCF) is simultaneous failure of multiple elements in a system under a common cause, and it is a common phenomenon in engineering systems with dependent elements. Several models and methods have been proposed for modeling and assessment of complex systems with CCF. In this paper, a new reliability assessment method is proposed for the systems suffering from CCF in a dynamic environment. The CCF among components is characterized by a BN, which allows for bidirectional reasoning. A proportional hazards model is applied to capture the dynamic working environment of components and then the reliability function of the system is obtained. The proposed method is validated through an illustrative example, and some comparative studies are also presented.  相似文献   

5.
Wood products that are subjected to sustained stress over a period of long duration may weaken, and this effect must be considered in models for the long-term reliability of lumber. The damage accumulation approach has been widely used for this purpose to set engineering standards. In this article, we revisit an accumulated damage model and propose a Bayesian framework for analysis. For parameter estimation and uncertainty quantification, we adopt approximation Bayesian computation (ABC) techniques to handle the complexities of the model. We demonstrate the effectiveness of our approach using both simulated and real data, and apply our fitted model to analyze long-term lumber reliability under a stochastic live loading scenario. Code is available at https://github.com/wongswk/abc-adm.  相似文献   

6.
Open source software systems that serve as key components of critical infrastructures in the society are still ever‐expanding now. Many open source software systems are developed in all parts of the world, that is, Firefox, Apache HTTP server, Linux, Android, and so on. Especially, a large‐scale open source solution composed of several open source software is now attracting attention as a next‐generation software development paradigm because of the cost reduction, quick delivery, and work saving. In this paper, we propose a new approach to software reliability assessment based on stochastic differential equations and a hierarchical Bayesian model in order to consider the interesting aspect of the collision status in the binding phase of open source software. Also, we analyze actual software fault‐count data to show numerical examples of software reliability assessment considering the component collision for several open source software. Moreover, we show that the proposed reliability analysis can assist improvement of quality for the large‐scale open source solution. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   

7.
In this article, the authors present a general methodology for age‐dependent reliability analysis of degrading or ageing components, structures and systems. The methodology is based on Bayesian methods and inference—its ability to incorporate prior information and on ideas that ageing can be thought of as age‐dependent change of beliefs about reliability parameters (mainly failure rate), when change of belief occurs not only because new failure data or other information becomes available with time but also because it continuously changes due to the flow of time and the evolution of beliefs. The main objective of this article is to present a clear way of how practitioners can apply Bayesian methods to deal with risk and reliability analysis considering ageing phenomena. The methodology describes step‐by‐step failure rate analysis of ageing components: from the Bayesian model building to its verification and generalization with Bayesian model averaging, which as the authors suggest in this article, could serve as an alternative for various goodness‐of‐fit assessment tools and as a universal tool to cope with various sources of uncertainty. The proposed methodology is able to deal with sparse and rare failure events, as is the case in electrical components, piping systems and various other systems with high reliability. In a case study of electrical instrumentation and control components, the proposed methodology was applied to analyse age‐dependent failure rates together with the treatment of uncertainty due to age‐dependent model selection. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   

8.
爆炸荷载对天然气管道(空管)的破坏作用研究   总被引:3,自引:0,他引:3  
王飞  王连来  刘广初 《爆破》2006,23(4):20-24
利用有限元计算软件ANSYS/LSDYNA中的ALE算法对爆炸荷载作用下天然气管道(空管)的破坏情况进行了数值模拟,分析了爆炸荷载下管道的变形情况、管道破坏过程以及管道内部应变的发展过程.最后与实验结果进行了比较.结果表明:误差在允许的范围内,ALE算法能够很好地模拟管道的破坏变形情况.  相似文献   

9.
In this article, we define a model for fault detection during the beta testing phase of a software design project. Given sampled data, we illustrate how to estimate the failure rate and the number of faults in the software using Bayesian statistical methods with various different prior distributions. Secondly, given a suitable cost function, we also show how to optimize the duration of a further test period for each one of the prior distribution structures considered. Michael Wiper acknowledges assistance from the Spanish Ministry of Science and Technology via the project BEC2000-0167 and support from projects SEJ2004-03303 and 06/HSE/0181/2004  相似文献   

10.
In this article, we consider the development and analysis of both attribute- and variable-data reliability growth models from a Bayesian perspective. We begin with an overview of a Bayesian attribute-data reliability growth model and illustrate how this model can be extended to cover the variable-data growth models as well. Bayesian analysis of these models requires inference over ordered regions, and even though closed-form results for posterior quantities can be obtained in the attribute-data case, variable-data models prove difficult. In general, when the number of test stages gets large, computations become burdensome and, more importantly, the results may become inaccurate due to computational difficulties. We illustrate how the difficulties in the posterior and predictive analyses can be overcome using Markov-chain Monte Carlo methods. We illustrate the implementation of the proposed models by using examples from both attribute and variable reliability growth data.  相似文献   

11.
ASME B31G是国际通用的评价腐蚀管线失效应力的标准,考虑到这种方法的保守性,以修正后的B31G模型作为研究腐蚀管线失效应力的基础,考虑管壁厚度、腐蚀速率、工作压力、缺陷深度等随机变量,构建腐蚀油气管线可靠性极限状态函数。然后,采用一次二阶矩法对腐蚀管线进行可靠性分析,得出管线的失效概率、可靠性指标以及剩余使用寿命。此外,为了更加规范的管理腐蚀管线,参照美国石油组织的相关规定,对不同失效概率的管线进行了等级划分。在最后的案例分析中,还讨论失效概率对不同变异系数对的敏感性,计算结果表明失效概率对管壁厚度的变异系数最为敏感。  相似文献   

12.
This paper addresses the issue, arising in probabilistic parameter estimation, which is sometimes referred to as the “Bayesian anomaly,” or also as the problem of “imperfect aggregation in Bayesian estimation.” The issue is clarified here from a generalized and theoretical point of view, but also in terms of a practical and mathematically consistent solution for probabilistic parameter estimation cases arising in actual reliability analysis and probabilistic risk assessment applications. More specifically, both theoretical and practical technical arguments are presented to show the reasons that make the purported anomaly manifest itself, and how the situations where it could in theory lead to serious estimation errors can be correctly handled. Interpretations and conclusions previously drawn with respect to the anomaly are also examined and re-evaluated in light of the new information and developments presented by the paper.  相似文献   

13.
无向De Bruijn网络的可靠性   总被引:1,自引:0,他引:1  
无向De Bruijn网络UB(d,n)是最受关注的网络模型之一。利用左邻域和右邻域的性质,首先研究这种网络拓扑的限制边连通性。证明了:当d≥3,n≥4时,UB(d,n)是超级限制边连通的。然后应用所得到的结果分析它们的可靠性,确定了其可靠多项式的前4d-4个系数。  相似文献   

14.
基于质量流量控制器(MFC)搭建了一套稀释装置,并通过高精度甲烷光谱仪验证了该装置的可靠性.试验结果表明,稀释比为0.01~0.02时,理论稀释浓度的相对误差不超过±4%;稀释比为0.04~0.1时,理论稀释浓度的相对误差在±0.5%以内.因此,稀释比很小时稀释装置的准确性欠佳.MFC上游输入气体压力变化对其输出气体流...  相似文献   

15.
This paper proposes a different likelihood formulation within the Bayesian paradigm for parameter estimation of reliability models. Moreover, the assessment of the uncertainties associated with parameters, the goodness of fit, and the model prediction of reliability are included in a systematic framework for better aiding the model selection procedure. Two case studies are appraised to highlight the contributions of the proposed method and demonstrate the differences between the proposed Bayesian formulation and an existing Bayesian formulation.  相似文献   

16.
Cognitive Reliability and Error Analysis Method (CREAM) is a common Human Reliability Analysis (HRA) method of second generation. In this paper, to improve the capabilities of CREAM, we propose a probabilistic method based on Bayesian Network (BN) to determine control mode and quantify Human Error Probability (HEP). The BN development process is described in a four‐phase methodology including (i) definition of the nodes and their states; (ii) building the graphical structure; (iii) quantification of BN through assessment of the Conditional Probability Tables (CPT) values and (iv) model validation. Intractability of knowledge acquisition of large CPTs is the most significant limitation of existing BN model of CREAM. So, the main contribution of this paper lies in its application of Recursive Noisy‐OR (RN‐OR) gate to treat large CPTs assessment and ease knowledge acquisition. RN‐OR allows combination of dependent Common Performance Conditions (CPCs). Finally, a quantitative HEP analysis is applied to enable more precise estimation of HEP through a probabilistic approach. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   

17.
可靠性工程中参数的一种估计方法   总被引:3,自引:0,他引:3  
提出了可靠性工程中参数的一种估计方法——新Bayes估计法,给出了失效概率、失效率的新Bayes估计的定义及其新Bayes估计。最后,结合实际问题的数据,进行了具体计算和分析,结果表明所提出的新Bayes估计法有效、可行,便于工程技术人员在工程中应用。  相似文献   

18.
本文研究现代排序问题一具有三重指标的批容量无限制平行分批排序问题。第一指标为最大延迟,第二指标为最大完工时间,第三指标为关于工件完工时间的任意正规函数。本文通过分析前两个指标最优解的性质给出了此问题的多项式时间算法。  相似文献   

19.
合成了一种新型天然气减阻剂3-烷基-4-胺基-5-巯基-1,2,4-三氮唑(AAMT),在天然气减阻剂室内评价系统上进行了减阻率测试,通过电化学分析及扫描电子显微镜对其在钢铁表面的成膜性能进行研究。结果表明:AAMT能够牢固吸附在输气管道内表面上形成一层光滑的弹性分子膜,显著改善了输气管道内表面的粗糙度。在AAMT浓度为4g/L、成膜时间为1.5h时,测得最大减阻率为10.03%。  相似文献   

20.
导爆管起爆网路可靠度分析   总被引:4,自引:0,他引:4  
为了防止因起爆网路失效而导致爆破任务失败,用概率论的方法对常用的几种导爆管起爆网路的准爆率进行了定量计算,并分析、评估和比较了这几种起爆网路的可靠度.从理论上分析证明了复式爆破网路、网络型接力式捆联网路和混联爆破网路是可靠的,能满足工程爆破的要求.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号