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201.
Optimality properties of multiway block designs are deduced from the general results of J. Kiefer's approximate-design theory. In the model with additive effects these optimality properties solely depend on the two-dimensional marginals of the designs. Uniform designs, and designs whose two-dimensional marginals are products of the one-dimensional marginals, are shown to be optimal. Approximate Youden designs are introduced for the case when the support sets of the two-dimensional marginals are prescribed in advance. They are optimal in a relatively small class of competing designs only.  相似文献   
202.
The basic purpose of probabilistic risk analysis is to make inferences about the probabilities of various postulated events, with an account of all relevant information such as prior knowledge and operating experience with the specific system under study, as well as experience with other similar systems. Estimation of the failure rate of a Poisson-type system leads to an especially simple Bayesian solution in closed form if the prior probability implied by the invariance properties of the problem is properly taken into account. This basic simplicity persists if a more realistic prior, representing order of magnitude knowledge of the rate parameter, is employed instead. Moreover, the more realistic prior allows direct incorporation of experience gained from other similar systems, without need to postulate a statistical model for an underlying ensemble. The analytic formalism is applied to actual nuclear reactor data.  相似文献   
203.
The concepts of the Bernoulli count process of a point process and Bernoulli sampling of a discrete parameter stochastic process are introduced. The Bernoulli count process determines the stochastic structure of the point process, and a process obtained by thinning a discrete parameter stochastic process by Bernoulli sampling satisfies the same property. Stationarity and the Markov property remain invariant under Bernoulli sampling.  相似文献   
204.
正态分布基于顺序统计量的一个结果   总被引:1,自引:0,他引:1  
关于正态分布总体给出了由两顺序统计量构成的一个函数,并讨论了其概率分布。这个结果可用于不完全的样本数据以及样本中可能存在异常值时,正态总体位置参数的区间估计。  相似文献   
205.
设计了适合熔盐电化学钽阳极氧化工艺的电化学反应炉及其温度控制系统,研究了模糊参数自整定PID控制器在电化学反应炉温度控制系统中的应用。对常规PID控制器和模糊参数自整定PID控制器进行了仿真对比,结果表明基于模糊参数在线自整定的PID控制器系统超调量明显减小,控制系统的动静态性能均得到改善。现场实验结果也证明了该设计方案是合理有效的。  相似文献   
206.
探讨了用节点法求解存在δ势时的一维谐振子势,并给出精确可靠的能级及本征波函数.讨论了势参数与能级移动及波函数变化的关系,并说明其物理本质.  相似文献   
207.
Inference in the presence of nuisance parameters is often carried out by using the χ2-approximation to the profile likelihood ratio statistic. However, in small samples, the accuracy of such procedures may be poor, in part because the profile likelihood does not behave as a true likelihood, in particular having a profile score bias and information bias which do not vanish. To account better for nuisance parameters, various researchers have suggested that inference be based on an additively adjusted version of the profile likelihood function. Each of these adjustments to the profile likelihood generally has the effect of reducing the bias of the associated profile score statistic. However, these adjustments are not applicable outside the specific parametric framework for which they were developed. In particular, it is often difficult or even impossible to apply them where the parameter about which inference is desired is multidimensional. In this paper, we propose a new adjustment function which leads to an adjusted profile likelihood having reduced score and information biases and is readily applicable to a general parametric framework, including the case of vector-valued parameters of interest. Examples are given to examine the performance of the new adjusted profile likelihood in small samples, and also to compare its performance with other adjusted profile likelihoods.  相似文献   
208.
本文讨论了一个超声全息成象系统及其主要参数对图象质量的影响。运用成象理论及其算法建立了最佳参数调整的关系式及基调整方法。本文运用这些关系式和方法,对多种不同类型的目标,如金属、塑料,植物与动物等,进行了超声成象处理,获得了十分良好的结果。  相似文献   
209.
本文用半试验半数值分析的方法识别转子的支承参数。在实验室条件下,对实际转子进行了试验、测量、计算和识别。所得结果令人满意,其精度可以满足工程上的要求。  相似文献   
210.
This article is an extension of Meyer and Sinn's results on the representation of arbitrary von Neumann-Morgenstern functions in - space when the probability distributions to be compared belong to a linear distribution class. It shows that, when absolute risk aversion decreases, stays constant, or increases not too fast, an increase in , given , increases the indifference curve slope: increased riskiness increases the required marginal compensation for risk when risk is measured by the standard deviation of wealth or income.I gratefully acknowledge useful comments by Wolfgang Buchholz, Kai Konrad, Jack Meyer, Hans Schneeweiß, Dominique Thon, and Bengt Arne Wickström.  相似文献   
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