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41.
本文在某些必要的适当条件下,采用一种独特的方式证明Wald意义下的最优决策的存在性.并表明:Wald意义下的最优决策作为一种π-Bayes最优决策实际上是局部的. 相似文献
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Göran Lindholm 《Accreditation and quality assurance》1998,3(7):296-297
This article describes on the idea behind Nordtest, the results of its activities and how Nordtest has influenced testing
and quality assurance. By financing projects in the field of technical testing Nordtest has been able to utilise the best
available Nordic knowledge and resources to respond to Nordic needs and has gained acceptance in all Nordic countries. During
Nordtest's 25 years of operation its projects have resulted in over 500 test methods and over 350 technical reports that are
widely used both within and outside the Nordic countries. Examples of some project results are given. Important issues in
testing and quality assurance are expressed in Nordtest position papers. Nordtest's active participation in the European and
global co-operation in testing and quality assurance is also described. 相似文献
43.
Hirokazu Yanagihara Tetsuji Tonda Chieko Matsumoto 《Journal of multivariate analysis》2005,96(2):1535-264
This paper examines asymptotic distributions of the likelihood ratio criteria, which are proposed under normality, for several hypotheses on covariance matrices when the true distribution of a population is a certain nonnormal distribution. It is well known that asymptotic distributions of test statistics depend on the fourth moments of the true population's distribution. We study the effects of nonnormality on the asymptotic distributions of the null and nonnull distributions of likelihood ratio criteria for covariance structures. 相似文献
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Singing teachers sometimes characterize voice quality in terms of "forward" and "backward" placement. In view of our traditional knowledge about voice production it is hard to explain any possible acoustic or articulatory differences between the voices so "placed." The analysis of the teachers' expert opinions demonstrates that, in general, a voice placed "forward" indicates a desirable quality that students should attain by the end of their studies. Productions that were perceived as "forward" and "backward" were selected from the listening test. The acoustic analysis of those productions reveals that the voice quality in the case of "forward" placement correlates with higher frequencies of the second (F2) and third (F3) formants, as well as with a more salient "singer's formant" in the voice. The five basic vowels were included in the investigation. 相似文献
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筛选高温下稳定的存储器并设计有效的温度补偿算法是实现井下声波测井数据存储的关键。为了快速测试不同存储器在高温下的故障情况以及错误校验纠错算法的温度补偿效果,该文设计了基于通用测试座的硬件系统,编写了基于MSComm控件的上位机控制软件,开发了模拟实际测井温度环境的测试策略,并对几种存储器进行了高温老化实验。结果表明,存储器在高温下(175℃)会出现彻底损坏、比特位翻转等故障,错误校验纠错算法可以提高存储器的使用温度。该设计不仅可以对符合开放NAND闪存接口协议的同类存储器进行快速的高温老化与筛选,而且对井下存储系统的设计有重要的参考意义。 相似文献
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根据中国聚变工程实验堆(CFETR)堆芯设计参数及燃料系统流程模型,采用平均停留时间方法,建立燃料循环子系统的氚转移模型用来描述氚在各子系统之间的输运、滞留等过程。采用该模型,分析了不同聚变功率水平、运行因子以及燃烧率对中国聚变工程实验堆的氚平衡以及启动氚投料量的影响。 相似文献