关于基解矩阵一个定理的简捷证明

一般地,常数矩阵A的特征向量不构成n维欧氏空间.针对这种普遍情况,用很初等的方法解决一类齐次线性微分方程基解矩阵的结构问题.     

Small sample properties of tests on homogeneity in one—way Anova and Meta—analysis

Received: January 12, 2000; revised version: July 26, 2000     

从“三斤鱼”的歧义现象看个体名词与度量词的相互搭配（二）

“数＋度量＋个体名词”结构在所指事物的个体数量上存在歧义现象，同一个异质个体事物名词分别加个体量词与度量词时存在有不同的语义变化，加度量词时表示的一定是人类领域意义上的同质“个体性”事物的类，侧重事物的属性。这种语义变化的制约性因素来自于度量词与个体名词两方面。     

广义James—Orlicz序列空间(英文)

本文考察了一类新的 Frechet 空间:广义 James—Orlicz 序列空间.文中不仅给出了此类空间的几何和空间结构,而且证明了它的可分性,ESA 性与 SA 性的关系,特别讨论了其范数的 p-齐次性,得到了一系列有用的结果.     

钌多氢化物的均相CO加氢反应催化性能研究及原位红外表征

用钌多氧化物作为均相ＣＯ加氢催化剂前体，在较低的温度和压力下进行釜式ＣＯ加氢反应，主要产物为低碳烷烃。实验结果表明，反应温度，时间，合成气比（Ｈ２／ＣＯ）和溶剂对ＣＯ转化率以及产物分布均产生影响。根据原位红外对反应的监测结果，提出了钌多氢化物均相ＣＯ加氢反应模式。     

Tests for the mean of a multivariate normal population

We study the problem of testing: H₀ : μ ∈ P against H₁ : μ ? P, based on a random sample of N observations from a p-dimensional normal distribution N_p(μ, Σ) with Σ > 0 and P a closed convex positively homogeneous set. We develop the likelihood-ratio test (LRT) for this problem. We show that the union-intersection principle leads to a test equivalent to the LRT. It also gives a large class of tests which are shown to be admissible by Stein's theorem (1956). Finally, we give the α-level cutoff points for the LRT.     

远程比喻的生成理念和心理机制

远程比喻的生成是以两类事物的相似性为基点,这一相似性既可以存在于两类事物中,也可以重新建构,作比的两类事物距离越远,比喻就越新奇.它的心理机制源于外显结构的意识突显性和深层结构的语义创建性的统一性,即编码者有意突显差异,引起注意,隐藏相似,运用同质异化或异质同化的联想思维方式,将相距甚远的事物并置,以期取得完形知觉大于部分知觉之和的审美效应.     

Heteroskedastic linear regression model with compositional response and covariates

Compositional data are known as a sort of complex multidimensional data with the feature that reflect the relative information rather than absolute information. There are a variety of models for regression analysis with compositional variables. Similar to the traditional regression analysis, the heteroskedasticity still exists in these models. However, the existing heteroskedastic regression analysis methods cannot apply in these models with compositional error term. In this paper, we mainly study the heteroskedastic linear regression model with compositional response and covariates. The parameter estimator is obtained through weighted least squares method. For the hypothesis test of parameter, the test statistic is based on the original least squares estimator and corresponding heteroskedasticity-consistent covariance matrix estimator. When the proposed method is applied to both simulation and real example, we use the original least squares method as a comparison during the whole process. The results implicate the model's practicality and effectiveness in regression analysis with heteroskedasticity.     

Optimal Maintenance Time for Repairable Systems Under Two Types of Failures

Determination of preventive maintenance is an important issue for systems under degradation. A typical maintenance policy calls for complete preventive repair actions at pre-scheduled times and minimal repair actions whenever a failure occurs. Under minimal repair, failures are modeled according to a non homogeneous Poisson process. A perfect preventive maintenance restores the system to the as good as new condition. The motivation for this article was a maintenance data set related to power switch disconnectors. Two different types of failures could be observed for these systems according to their causes. The major difference between these types of failures is their costs. Assuming that the system will be in operation for an infinite time, we find the expected cost per unit of time for each preventive maintenance policy and hence obtain the optimal strategy as a function of the processes intensities. Assuming a parametrical form for the intensity function, large sample estimates for the optimal maintenance check points are obtained and discussed.     

关于丢番图方程(n-1)_∑~(k=0)[1-(80s+72)k]~r=[1+(80s+72)~n]~7

本文证明了：当n，r为正整数，s为非负整数，丢番图方程无整数解。