Empirical Bayes test for scale exponential family

In this paper, we consider the empirical Bayes (EB) test problem for the scale parameters in the scale exponential family with a weighted linear loss function. The EB test rules are constructed by the kernel estimation method. The asymptotical optimality and convergence rates of the EB test rules are obtained. The main results are illustrated by applying the proposed test to type II censored data from the exponential distribution and to the test problem for the dispersion parameter in the linear regression model. __________ Translated from Journal of University of Science and Technology of China, 2004, 34(1): 1–10     

随机线性系统保成本控制的线性矩阵不等式方法

考虑具有二次成本函数的随机线性系统,研究了状态反馈控制的保证成本控制问题.依据线性矩阵不等式得到了保证成本控制器存在的充分条件,最后得到了随机线性闭环系统保证成本最小的最优保证成本控制律的表达式.     

系统树中的近似Bayes方法

本文利用近似Ｂａｙｅｓ方法对一个具有树形结构的成败型系统的可靠性进行估计．本文证明了利用近似Ｂａｙｅｓ方法对系统的可靠性参数的估计，具点估计在Ｆｉｓｈｅｒ意义下是渐近有效的，其相应的置信下限也是Ｆｉｓｈｅｒ意义下渐近有效的．     

响应变量随机缺失下的广义变系数模型的估计

在响应变量随机缺失时,利用拟似然方法给出了广义变系数模型中非参数函数系数的估计.研究了所得到的估计的渐近性质,求出了估计的渐近偏差与渐近方差,并进行模拟比较.     

求解约束优化问题的两个微分方程算法

本文给出求解具有等式约束和不等式约束的非线性优化问题的一阶信息和二阶信息的两个微分方程系统,问题的局部最优解是这两个微分方程系统的渐近稳定的平衡点,给出了这两个微分方程系统的Euler离散迭代格式并证明了它们的收敛性定理,用龙格库塔法分别求解两个微分方程系统．我们构造了搜索方向由两个微分系统计算,步长采用Armijo线搜索的算法分别求解这个约束最优化问题,在局部Lipschitz条件下基于二阶信息的微分方程系统的迭代方法具有二阶的收敛速度。我们给出的数值结果表明龙格库塔的微分方程算法具有较好的稳定性和更高的精确度,求解二阶信息的微分方程系统的方法具有更快的收敛速度．     

一类具时滞生态系统的概周期解

对具有限时滞和带扩散效应的Lotka—Volterra系统进行了研究，证明了在一定条件下系统是一致持久的，并利用建立Lyapunov函数的方法得到了系统的概周期解存在惟一和全局渐近稳定的充分条件。     

The multi‐color Ramsey number of an odd cycle

Let r_k(G) be the k‐color Ramsey number of a graph G. It is shown that for k?2 and that r_k(C_{2m+ 1})?(c^kk!)^1/m if the Ramsey graphs of r_k(C_{2m+ 1}) are not far away from being regular. © 2009 Wiley Periodicals, Inc. J Graph Theory 62: 324–328, 2009     

Homotopic Classification of Yang–Mills Vacua Taking into Account Causality

Existence of θ-vacuum states in Yang–Mills theories defined over asymptotically flat space-times examined taking into account not only the topology but the complicated causal structure of these space-times, too. By a result of Galloway apparently causality makes all vacuum states, seen by a distant observer, homotopically equivalent making the introduction of θ-terms unnecessary. But a more careful analysis shows that certain twisted classical vacuum states survive even in this case eventually leading to the conclusion that the concept of “θ-vacua” is meaningful in the case of general Yang–Mills theories. We give a classification of these vacuum states based on Isham’s results showing that the Yang–Mills vacuum has the same complexity as in the flat Minkowskian case hence the general CP-problem is not more complicated than the well-known flat one. We also construct the θ vacua rigorously via geometric quantization. PACS numbers: 11.15, 11.30.E, 04.20.G, 04.70     

Forward attraction in nonautonomous difference equations

Two types of attractors consisting of families of sets that are mapped into each other under the dynamics have been defined for nonautonomous difference equations, one using pullback convergence with information about the system in the past and the other using forward convergence with information about the system in the future. In both cases, the component sets are constructed using a pullback argument within a positively invariant family of sets. The forward attractor so constructed also uses information about the past, which is very restrictive and not essential for determining future behaviour. Here an alternative is investigated, essentially the omega-limit set of the system, which Chepyzhov and Vishik called the uniform attractor. It is shown here that this set is asymptotically positively invariant, thus providing it with an hitherto missing form of invariance, if in somewhat weaker than usual, that one expects an attractor to possess. As a consequence this set provides useful information about the behaviour in current time during the approach to the limit.