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991.
本文给出一类夸克质量矩阵与CP破坏参量的精确解析关系. 有关结果适用于唯象研究不同质量矩阵模型及其CP破坏效应的细微差别. 相似文献
992.
Antonio Aizpuru Francisco J. Garcí a-Pacheco Consuelo Pé rez-Eslava 《Proceedings of the American Mathematical Society》2007,135(11):3571-3579
Some classical results about uniform convergence of unconditionally convergent series are generalized to weakly unconditionally Cauchy series by means of the matrix summability method for regular matrices.
993.
The classical family of Wishart distributions on a cone of positive definite matrices and its fundamental features are extended to a family of generalized Wishart distributions on a homogeneous cone using the theory of exponential families. The generalized Wishart distributions include all known families of Wishart distributions as special cases. The relationships to graphical models and Bayesian statistics are indicated. 相似文献
994.
Using determinant representations for partition functions of the corresponding variants of square-ice models and the method recently proposed by one of us, we investigate refined enumerations of vertically symmetric alternating-sign matrices, off-diagonally symmetric alternating-sign matrices, and alternating-sign matrices with a U-turn boundary. For all these cases, we find explicit formulas for refined enumerations. In particular, we prove the Kutin–Yuen conjecture. 相似文献
995.
The LBLT factorization of Bunch for solving linear systems involving a symmetric indefinite tridiagonal matrix T is a stable, efficient method. It computes a unit lower triangular matrix L and a block 1 × 1 and 2 × 2 matrix B such that T=LBLT. Choosing the pivot size requires knowing a priori the largest element σ of T in magnitude. In some applications, it is required to factor T as it is formed without necessarily knowing σ. In this paper, we present a modification of the Bunch algorithm that can satisfy this requirement. We demonstrate that this modification exhibits the same bound on the growth factor as the Bunch algorithm and is likewise normwise backward stable. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
996.
Yanhua Wang Shuyuan He Lixing Zhu Kam C. Yuen 《Probability Theory and Related Fields》2007,138(1-2):235-267
For censored response variable against projected co-variable, a generalized linear model with an unknown link function can
cover almost all existing models under censorship. Its special cases include the accelerated failure time model with censored
data. Such a model in the uncensored case is called the single-index model in econometrics. In this paper, we systematically
study the asymptotic properties. We derive the central limit theorem and the law of the iterated logarithm for an estimator
of the direction parameter. We also obtain the optimal convergence rate of an estimator of the unknown link function in the
model.
相似文献
997.
The parsimony haplotyping problem was shown to be NP-hard when each genotype had k?3ambiguous positions, while the case for k?2 was open. In this paper, we show that the case for k?2 is polynomial, and we give approximation and FPT algorithms for the general case of k?0 ambiguous positions. 相似文献
998.
In this paper, we analyzed stochastic chaos and Hopf bifurcation of stochastic Bonhoeffer–van der Pol (SBVP for short) system with bounded random parameter of an arch-like probability density function. The modifier ‘stochastic’ here implies dependent on some random parameter. In order to study the dynamical behavior of the SBVP system, Chebyshev polynomial approximation is applied to transform the SBVP system into its equivalent deterministic system, whose response can be readily obtained by conventional numerical methods. Thus, we can further explore the nonlinear phenomena in SBVP system. Stochastic chaos and Hopf bifurcation analyzed here are by and large similar to those in the deterministic mean-parameter Bonhoeffer–van der Pol system (DM–BVP for short) but there are also some featuring differences between them shown by numerical results. For example, in the SBVP system the parameter interval matching chaotic responses diffuses into a wider one, which further grows wider with increasing of intensity of the random variable. The shapes of limit cycles in the SBVP system are some different from that in the DM–BVP system, and the sizes of limit cycles become smaller with the increasing of intensity of the random variable. And some biological explanations are given. 相似文献
999.
Olav Kallenberg 《Acta Appl Math》2007,96(1-3):271-282
The aim of this paper is to convey the basic ideas regarding some local hitting and conditioning properties of random measures.
Some very general results are obtainable in the special case of simple point processes. Though much of this theory has no
counterpart for general random measures, similar results do exist in two cases of special interest—for local time random measures
and for Dawson–Watanabe superprocesses. This is an informal account of some of the basic hitting and conditioning properties
common to all three cases. Precise statements and proofs will be provided elsewhere. 相似文献
1000.
引入了本原无限布尔方阵的概念,给出了无限布尔方阵为本原阵的一个充分必要条件,最后给出了一类本原无限布尔方阵的本原指数集的刻划. 相似文献