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161.
对于n秩单李代数g,当采用Dynkin关于素根的分类时,其不可约表示可以用n个非负整数Λ_(αi)标记,也可通过初等表示的权用数组li来标记。利用Cartan逆矩阵,我们给出了计算Λ_(α_i)与li之间关系的方法。对于B_n、C_n、D_n和F_4,利用Cartan逆矩阵证明了这些li是与采用Cartan关于素根的分类时的Λi是一致的。 相似文献
162.
Mike Jacroux 《Journal of statistical planning and inference》1984,9(2):259-267
In this paper we consider proper block designs and derive an upper bound for the number of blocks which can have a fixed number of symbols common with a given block of the design. To arrive at the desired bound, a generalization of an integer programming theorem due to Bush (1976) is first obtained. The integer programming theorem is then used to derive the main result of this paper. The bound given here is then compared with a similar bound obtained by Kageyama and Tsuji (1977). 相似文献
163.
Masahiro Nakaoka 《Researches on Population Ecology》1993,35(2):199-213
Summary Long-term variation in recruitment was estimated by constructing projection matrices for a marine bivalve,Yoldia notabilis, at two stations in Otsuchi Bay, northeastern Japan, and the effects of its variation on population dynamics were examined
using a simple matrix model. The matrix model was developed from the Leslie matrix, in which the population growth rate λ
was expressed as a function of recruitment rater
0. The equilibrium recruitment rater
s, or the recruitment rate required to maintain population at constant size (λ=1), was expressed by the reciprocal of the reproductive
value of a newly recruited individual. The estimates ofr
s for the field population were lower at the shallower station than at the deeper station, reflecting higher survivorship and
fecundity. Past recruitment rate estimated both by the field samplings for 3 years and by the back-calculation from the current
age structure for over 10 years showed large yearly variation, ranging between 0 and 58.6×10−4. The estimates were larger thanr
s, and hence, large enough to increase population size (λ>1) only in approximately one-third of the estimated years. This suggests
that the population has been maintained by occasional successful recruitment occurring once every few years. 相似文献
164.
段俊生 《内蒙古工业大学学报》1995,14(3):39-42
证明了分配格L上的准自反矩阵A(满足条件a(11)=···a(mn)≥a(ij)的矩阵)的伴随矩阵adjA与收敛指数i(A)之间的关系adjA=A(I(A).从而得到A幂等的一个充要条件为A=adjA及A的伴随矩阵adjA的一些性质。 相似文献
165.
给出了一类矩阵的行列式的不等式|A+B|s≥|A|s+|B|s,而Minkowski不等式及其推广均可视为这一结果的简单推论. 相似文献
166.
Uniformly minimum-variance unbiased (UMVU) estimators of the total risk and the mean-squared-error (MSE) matrix of the Stein estimator for the multivariate normal mean with unknown covariance matrix are proposed. The estimated MSE matrix is helpful in identifying the components which contribute most to the total risk. It also contains information about the performance of the shrinkage estimator with respect to other quadratic loss functions. 相似文献
167.
168.
169.
TRIZ理论与计算机辅助创新集成已成为目前技术和产品创新的研究热点,运用TRIZ理论,对当前“数据结构”多媒体教学的优势和存在的问题进行了分析和研究,应用TRIZ理论中的矛盾矩阵和40条创新原理对多媒体教学中的不足之处提出了改善性的对策与建议. 相似文献
170.
Hu Yang 《统计学通讯:理论与方法》2013,42(1):70-80
Sakall?oglu et al. (2001) dealt with the comparisons among the ridge estimator, Liu estimator, and iteration estimator. Akdeniz and Erol (2003) have compared the (almost unbiased) generalized ridge regression estimator with the (almost unbiased) generalized Liu estimator in the matrix mean squared error sense. In this article, we study the ridge estimator and Liu estimator with respect to linear equality restriction, and establish some sufficient conditions for the superiority of the restricted ridge estimator over the restricted Liu estimator and the superiority of the restricted Liu estimator over the restricted ridge estimator under mean squared error matrix, respectively. Furthermore, we give a numerical example. 相似文献