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71.
In this paper, the design of reliability sampling plans for the Pareto lifetime model under progressive Type-II right censoring is considered. Sampling plans are derived using the decision theoretic approach with a suitable loss or cost function that consists of sampling cost, rejection cost, and acceptance cost. The decision rule is based on the estimated reliability function. Plans are constructed within the Bayesian context using the natural conjugate prior. Simulations for evaluating the Bayes risk are carried out and the optimal sampling plans are reported for various sample sizes, observed number of failures and removal probabilities.  相似文献   
72.
由模糊可靠性的基本概念和原理,建立了一套计算混联系统(Ⅱ)的模糊可靠性公式  相似文献   
73.
This paper reviews recent developments in the stochastic comparison of order statistics. The results discussed are basically: (l) Stochastic comparisons of linear combinations of order statistics from distributions F and G where G?1 F is convex or starshaped. (2) Stochastic comparisons of individual order statistics and of vectors of order statistics from underlying heterogeneous distributions by the use of majorization and Schur function theory. (3) Stochastic comparison of random processes. Applications to reliability problems are presented illustrating the use and value of the theoretical results described  相似文献   
74.
In this paper solutions of renewal-type integral equations are studied. It is proved that a recursively spades;efined approximation to the solution has some nice convergence properties. Some simple bounds and other results on the renewal function and the renewal spades;,ensity are obtained.  相似文献   
75.
As assumed hypothetical consensus category corresponding to a case being classified provides a basis for assessment of reliability of judges. Equivalent judges are characterised by the joint probability distribution of the judge assignment and the consensus category. Estimates of the conditional probabilities of judge assignment given consensus category and of consensus category given judge assignments are indices of reliability. All parameters can be estimated if data include classifications of a number of cases by 3 or more judges. Restrictive assumptions are imposed to obtain models for data from classifications by two judges. Maximum likelihood estimation is discussed and illustrated by example for the 3 or more judges case.  相似文献   
76.
本文从提高数控系统的可靠性出发,阐述了数控系统抗干扰设计的必要性。具体讨论了数控系统中一些实用而有效的抗干扰技术。  相似文献   
77.
The aging domestic oil production infrastructure represents a high risk to the environment because of the type of fluids being handled (oil and brine) and the potential for accidental release of these fluids into sensitive ecosystems. Currently, there is not a quantitative risk model directly applicable to onshore oil exploration and production (E&P) facilities. We report on a probabilistic reliability model created for onshore exploration and production (E&P) facilities. Reliability theory, failure modes and effects analysis (FMEA), and event trees were used to develop the model estimates of the failure probability of typical oil production equipment. Monte Carlo simulation was used to translate uncertainty in input parameter values to uncertainty in the model output. The predicted failure rates were calibrated to available failure rate information by adjusting probability density function parameters used as random variates in the Monte Carlo simulations. The mean and standard deviation of normal variate distributions from which the Weibull distribution characteristic life was chosen were used as adjustable parameters in the model calibration. The model was applied to oil production leases in the Tallgrass Prairie Preserve, Oklahoma. We present the estimated failure probability due to the combination of the most significant failure modes associated with each type of equipment (pumps, tanks, and pipes). The results show that the estimated probability of failure for tanks is about the same as that for pipes, but that pumps have much lower failure probability. The model can provide necessary equipment reliability information for proactive risk management at the lease level by providing quantitative information to base allocation of maintenance resources to high-risk equipment that will minimize both lost production and ecosystem damage.  相似文献   
78.
人的可靠性与人为差错   总被引:5,自引:0,他引:5  
分析论述了影响人的可靠性的因素 ,提出了提高人的可靠性、减少人为差错的措施和方法。  相似文献   
79.
利用故障频次主次图、故障比重比主次图及危害度的综合分析方法,对所采集的某系列加工中心现场故障信息进行了统计分析,找出了其可靠性的薄弱环节,进一步明确了加工中心可靠性工作的改进方向,为其他机电产品的可靠性研究提供了较实用的方法。  相似文献   
80.
世谱、宗谱、家谱,总称谱谍,是中华民族传统文化的重要组成部分,它与正史、方志共同构成了中华民族历史的三大支柱。此文着重分析了绍兴《姒氏世谱》的史料价值,认为该谱所载史事与正史、地志基本一致,对先人业绩并无夸张过誉之辞,所以可靠性较大;该谱叙述世系清楚完整,为他书所未见,可补正史、地志之缺;该谱还蕴含人口学、民俗学、社会学、民族学方面的资料,更可拓宽越文化研究的领域。由此可见,搜集、整理和研究大禹后裔宗谱,任务急迫,意义重大。  相似文献   
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