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1.
Hierarchical Bayesian method for estimating the failure probabilityp i under DOOF by taking the quasi-Beta distributionB(p i−1, 1, 1,b) as the prior distribution is proposed in this paper. The weighted Least Squares Estimate method was used to obtain the formula for computing reliability distribution parameters and estimating the reliability characteristic values under DOOF. Taking one type of aerospace electrical connector as an example, the correctness of the above method through statistical analysis of electrical connector accelerated life test data was verified. Project (No. 59975081) supported by the National Natural Science Foundation of China  相似文献   

2.
对无失效数据(ti,ni),在时刻ti的失效概率pi=P{T  相似文献   

3.
对无失效数据(ti,ni),在时刻ti的失效概率pi=P{T刍ti}的先验分布为截尾Gamma分布时,给出了pi的Bayes估计和多层Bayes估计,从而得到无失效数据情形可靠度的估计.  相似文献   

4.
本文给出了在ti时刻的失效概率pi=p{T〈ti}的Bayes可靠性分析,从而得到极值分布无失效数据下的可靠性估计。  相似文献   

5.
The over-load protective relay is widely used for motor protection. The reliability of the over-load protective relay directly affects the safe running of a motor. The reliability testing and reliability analysis of the over-load protective relay is an important way to improve the reliability of products. In this paper, the reliability test method of the over-load protective relay is studied, and the reliability tests of the typical products are carried out on a reliability tester developed by authors. In terms of the testing results, the reliability analysis is finished. The failure reasons are found and the measures are put forward to improve the reliability of the products.  相似文献   

6.
随着我国计划生育政策的推行,"独二代"将成为未来社会的主要现象。与"独一代"相比,"独二代"凸显出更多的特质,这种变化无疑为高等教育管理带来了严峻挑战。本文通过剖析"独二代"特质,探讨高等教育管理如何调整和改革管理理念与模式以应对这种挑战。  相似文献   

7.
在不假定退化轨道的基础上,提出利用时间序列的方法,使用ARIMA模型对退化数据进行建模,拟合其退化规律,预测失效寿命,进而进行可靠性评估.并给出实例,说明该方法具有较好的适用性和有效性.  相似文献   

8.
In standard canonical correlation analysis (CCA), the data from definite datasets are used to estimate their canonical correlation. In real applications, for example in bilingual text retrieval, it may have a great portion of data that we do not know which set it belongs to. This part of data is called unlabeled data, while the rest from definite datasets is called labeled data. We propose a novel method called regularized canonical correlation analysis (RCCA), which makes use of both labeled and unlabeled samples. Specifically, we learn to approximate canonical correlation as if all data were labeled. Then, we describe a generalization of RCCA for the multi-set situation. Experiments on four real world datasets, Yeast, Cloud, Iris, and Haberman, demonstrate that, by incorporating the unlabeled data points, the accuracy of correlation coefficients can be improved by over 30%.  相似文献   

9.
Tolerance design, including tolerance analysis and distribution, is an important part of the electronic system’s reli- ability design. The traditional design needs to construct mathematic model of material circuit, which involves large amount of workload and lacks of practicability. This paper discusses the basic theory of electronic system’s reliability tolerance design and presents a new design method based on EDA (Electronic Design Automatic) software. This method has been validated through the application research on reliability tolerance design of the DC hybrid contactor’s control circuit.  相似文献   

10.
A motion information analysis system based on the acceleration data is proposed in this paper,consisting of filtering,feature extraction and classification.The Kalman filter is adopted to eliminate the noise.With the time-domain and frequency-domain analysis,acceleration features like the amplitude,the period and the acceleration region values are obtained.Furthermore,the accuracy of the motion classification is improved by using the k-nearest neighbor (KNN) algorithm.  相似文献   

11.
高级汉语口语测验将高水平学习者的口语能力,操作性地定义为在听—说模式和独白模式下的议论性语篇表达的能力。本研究针对评分员使用两种评分标准对67名外国考生完成听后说题型的评分进行了检验。概化理论的分析结果显示,两种评分标准的测验信度都达到了优良标准;评分标准一使用两名评分员即可使测验信度达到优良(概化系数为0.826),评分标准二则需要使用三名评分员才能使测验信度达到优良。  相似文献   

12.
通过对圆锥头的失效表现、原因分析,寻求出间接提高圆锥头可靠性能的办法,以解决实际问题.  相似文献   

13.
The main purpose of this paper is to demonstrate how to apply the Hierarchical Linear Modeling (HLM) technique to multi-wave Curriculum-Based Measurement (CBM) measures in modeling academic growth and assessing its relations to student- and instruction-related variables. HLM has advantages over other statistical methods (e.g., repeated measures ANOVA, Structural Equation Modeling) in modeling academic growth. The advantages include allowing more flexible research designs in collecting multiple data points and estimating growth rates and their relations to correlates in more reliable, accurate ways. CBM, as a multi-wave progressmonitoring system, also has distinctive psychometric features that facilitate longitudinal research on academic skill development. These features include provision of multiple data points within short time periods, good validity and reliability, and sensitivity for detecting small degrees of change. Finally, research questions related to assessing the academic growth of students with learning difficulties and using assessment results to improve educational practices for them are discussed  相似文献   

14.
Background knowledge is important for data mining, especially in complicated situation. Ontological engineering is the successor of knowledge engineering. The sharable knowledge bases built on ontology can be used to provide background knowledge to direct the process of data mining. This paper gives a common introduction to the method and presents a practical analysis example using SVM (support vector machine) as the classifier. Gene Ontology and the accompanying annotations compose a big knowledge base, on which many researches have been carried out. Microarray dataset is the output of DNA chip. With the help of Gene Ontology we present a more elaborate analysis on microarray data than former researchers. The method can also be used in other fields with similar scenario.  相似文献   

15.
工业厂房承重结构体系可靠性定量分析   总被引:1,自引:0,他引:1  
以某单层工业厂房承重结构体系为例,运用《工业厂房可靠性鉴定标准》对其进行可靠性鉴定评级,并在此基础上,运用系统失效分析法(故障树分析)进行可靠性定量分析,从而使单层工业厂房可靠性鉴定向定量化分析过渡。  相似文献   

16.
本文参考有关统计资料,对我国新颁公路桥规JTJ023-85中钢筋混凝土构件承载能力的可靠指标进行了计算分析,并讨论了影响构件可靠度指标的几个主要因素。采用的方法是一种近似概率计算方法——一次二阶矩法,即只考虑随机变量的平均值和标准差两统计参数,对设计表达式进行线性化处理。结果表明,延性破坏构件在荷载组合G+Q_1下β平均值为3.6,在G+Q_2下β平均值为2.8;脆性破坏构件,则分别为4.1和3.3。这是新规范所反映的钢筋混凝土构件可靠度的基本水平。另外在某些荷载效应比值下提高了荷载安全系数和对脆性破坏构件考虑了工作条件系数,都较为合理。但构件在不同荷载情况下尚不能得到比较一致的可靠度。抗力和荷载效应的分项系数以及荷载的标准值还需进一步研讨。  相似文献   

17.
A parallel system with two active components and a cold standby unit is studied in this paper. The two simultaneously working components are dependent and the copula function is used to model their dependence. An explicit expression is obtained for the mean time to failure of the system in terms of the copula function and marginal lifetime distributions in two different cases As an application, numerical calculations are presented corresponding to two different copula functions and marginal lifetime distributions.  相似文献   

18.
采用带有随机微分方程的非线性混合效应模型对群体药物代谢动力学数据建模,通过在状态方程中引入随机项,将常微分方程扩展到随机微分方程.和常微分方程相比,随机微分方程可解决群体药物代谢动力学模型中相关残差问题.利用贝叶斯估计对非线性混合效应随机微分方程模型参数进行估计,给出群体参数及个体参数的精确后验分布,将Gibbs和Metropolis-Hastings算法相结合,给出参数估计值.通过计算机模拟和实例分析验证了方法的可靠性,结果表明利用非线性混合效应随机微分方程模型及贝叶斯估计方法分析群体药物代谢动力学数据是可行的.  相似文献   

19.
Based on a multiobjective approach whose objective function (OF) vector collects stochastic reliability performance and structural cost indices, a structural optimization criterion for mechanical systems subject to random vibrations is presented for supporting engineer's design. This criterion differs from the most commonly used conventional optimum design criterion for random vibrating structure, which is based on minimizing displacement or acceleration variance of main structure responses, without considering explicitly required performances against failure. The proposed criterion can properly take into account the design-reliability required performances, and it becomes a more efficient support for structural engineering decision making. The multiobjective optimum (MOO) design of a tuned mass damper (TMD) has been developed in a typical seismic design problem, to control structural vibration induced on a multi-storey building structure excited by nonstationary base acceleration random process A numerical example for a three-storey building is developed and a sensitivity analysis is carried out. The results are shown in a useful manner for TMD design decision support.  相似文献   

20.
Finite element reliability analysis of slope stability   总被引:1,自引:0,他引:1  
The method of nonlinear finite element reliability analysis (FERA) of slope stability using the technique of slip surface stress analysis (SSA) is studied. The limit state function that can consider the direction of slip surface is given, and the formulations of FERA based on incremental tangent stiffness method and modified Aitken accelerating algorithm are developed. The limited step length iteration method (LSLIM) is adopted to calculate the reliability index. The nonlinear FERA code using the SSA technique is developed and the main flow chart is illustrated. Numerical examples are used to demonstrate the efficiency and robustness of this method. It is found that the accelerating convergence algorithm proposed in this study proves to be very efficient for it can reduce the iteration number greatly, and LSLIM is also efficient for it can assure the convergence of the iteration of the reliability index.  相似文献   

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