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91.
本文给出一组托卡马克堆芯等离子体功率平衡方程,它描述了在非自持和非麦氏分布情况下等离子体功率平衡的问题,计算结果表明。在现实可行的聚变堆工程和相应的等离子体参数情况下,堆芯中每秒可产生聚变中子PN大于10~19。 相似文献
92.
The coefficient of variation is an important parameter in many physical, biological and medical sciences. In this paper we study the estimation of the square of the coefficient of variation in a weighted inverse Gaussian model which is a mixture of the inverse Gaussian and the length biased inverse Gaussian distribution. This represents a rich family of distributions for different values of the mixing parameter and can be used for modelling various life testing situations. The maximum likelihood as well as the Bayes estimates of the parameters are obtained. These estimates are used to derive the estimates of the square of the coefficient of variation of the model under study. Several important data sets are analysed to illustrate the results. © 1996 John Wiley & Sons, Ltd. 相似文献
93.
K. Ramachandra 《Proceedings Mathematical Sciences》1995,105(3):273-279
Some very precise results (see Theorems 4 and 5) are proved about thea-values of thelth derivative of a class of generalized Dirichlet series, forl≥l o =l o(a) (l o being a large constant). In particular for the precise results on the zeros ofζ (1) (s) —a (a any complex constant andl≥l o) see Theorems 1 and 2 of the introduction. 相似文献
94.
分布形式未知的矩法<英> 总被引:1,自引:0,他引:1
我们考虑分布形式未知的矩法,假设分布函数F_θ(x)可用一多项式表示或逼近。多项式的阶数r未知,其系数为未知参数θ_1,…,θ_r。我们给出了θ_1,…,θ_r的一种新的矩法估计,r可自动地求得,估计是强一致的。 相似文献
95.
Jõgi Henna 《Annals of the Institute of Statistical Mathematics》1985,37(1):235-240
Summary Suppose thatH is a mixture of distributions for a given familyF A necessary and sufficient condition is obtained under whichH is, in fact, a finite mixture. An estimator of the number of distributions constituting the mixture is proposed assuming
that the mixture is finite and its asymptotic properties are investigated. 相似文献
96.
Let r1 > r2 > … be the sample canonical correlations in a sample of size n from a multivariate normal population partitioned into two subvectors with population canonical correlations 1 > 2 > …. Let one of the subvectors be augmented by adding one or more variables to it. For the increase in the largest canonical correlation, Δr in the sample and Δ in the population, it is shown that √n(Δr − Δ) → DN(0, σ2) and a formula for σ2 is derived. 相似文献
97.
In developing a new method to measure the phase distribution of a light wave utilizing the adaptive control of the pupil function with a liquid crystal panel, the optimization procedure for the adaptive control is shown to improve when a local algorithm is adopted. The feasibility of the proposed system is confirmed by computer simulation as well as by some basic experiments. 相似文献
98.
Comparison of certain value-at-risk estimation methods for the two-parameter Weibull loss distribution 总被引:2,自引:0,他引:2
Omer L. Gebizlioglu Birdal ?eno?luYeliz Mert Kantar 《Journal of Computational and Applied Mathematics》2011,235(11):3304-3314
The Weibull distribution is one of the most important distributions that is utilized as a probability model for loss amounts in connection with actuarial and financial risk management problems. This paper considers the Weibull distribution and its quantiles in the context of estimation of a risk measure called Value-at-Risk (VaR). VaR is simply the maximum loss in a specified period with a pre-assigned probability level. We attempt to present certain estimation methods for VaR as a quantile of a distribution and compare these methods with respect to their deficiency (Def) values. Along this line, the results of some Monte Carlo simulations, that we have conducted for detailed investigations on the efficiency of the estimators as compared to MLE, are provided. 相似文献
99.
100.
多釜串联模型停留时间分布方差的推导 总被引:1,自引:0,他引:1
简要分析了理想反应器的特点,并指出现实反应器与理想反应器的区别,介绍了多釜串联模型描述实际反应器的思想.针对多釜串联模型的停留时间分布的计算函数进行逐步的推导,以阶跃法对模型进行分析,采用数学归纳法和分部积分法等方法推导出了多釜串联模型无因次停留时间分布函数表达式;根据停留时间分布密度函数定义,推导出了无因次停留时间分布密度函数的表达式;根据概率中方差的定义,推导出了无因次方差的表达式. 相似文献