对多普勒效应的讨论

当波源和观察者有相对运动时,观察者会感受到波源频率发生变化。     

浅析现代汉语词汇变化特征与中国社会的关系

词汇是语言的建筑材料,是语音和语义通过社会约定俗成的统一体,词汇的这种社会属性决定了词汇的变化离不开社会.我们可以从词汇变化了解社会的过去和现在,也可以从社会变化中找出词汇变化的原因.改革开放以来,汉语词汇发生了巨大的变化,新词全方位地增长,感情色彩词的褒贬义转移,外来词的繁荣,专门术语生活化以及网络用语的盛行都反映出了社会变革对词汇系统的巨大影响.其变化是词汇内在结构、功能与外部社会合力的结果.     

魏晋浮竞世风与诗歌新变

“浮竞”风尚促使魏晋诗坛形成了以“丽藻”为主要评价标准的审美观念,也促使诗坛“求丽”的倾向持续流行,并最终在西晋时期形成“繁缛”的特征。伴随这一过程,魏晋诗坛展现出三点新变：第一,“赋”成为诗歌创作的主要手法,促使诗歌日渐靡丽;第二,形成“先辞后情”的审美标准,“为文造情”现象突出;第三,文人乐府诗的格调得到提升,并实现了“化俗为雅”的转变。     

我国社会阶级阶层的新变化对党的建设的新要求

在改革开放和现代化建设的新时期 .我国社会阶级阶层出现新变化 ,工人阶级和农民阶级内部出现分化 ,新的社会阶层形成。这引起了党的阶级基础和群众基础的变化 ,要求党必须增强党的阶级基础和扩大党的群众基础 ,使党的建设在新时期面临着新的挑战     

工业化进程与制度变迁关系分析

制度变迁和工业化进程的关系是密切相关的,不同的工业化阶段,有主导制度变迁的不同力量。我国制度变迁由四个阶段组成,即政府主导型变迁阶段、效率主导型变迁阶段、技术创新主导型变迁阶段、分配主导型变迁阶段,当前主要采用的是效率主导型制度变迁模式。     

从教育价值观的历史变迁看现代教育价值的取向

教育价值观是教育基本理论研究的重要范畴之一 ,是人们对教育价值关系的认识和评价以及在此基础上所确定的行为取向标准 ,它直接影响甚至控制教育实践活动。教育价值取向既是时代要求的产物 ,又是对时代要求所作的应答。符合时代要求的现代教育价值取向 ,促进了个人和社会可持续发展的整合。     

Monitoring Structural Changes in Generalized Linear Models

In this article, we introduce two monitoring schemes to (sequentially) detect structural changes in generalized linear models and develop asymptotic theories for them. The first method is based on cumulative sums (CUSUM) of weighted residuals, in which the unknown in-control parameters have been replaced by its maximum likelihood (ML) estimate from the training sample, whereas the second scheme makes use of moving sums (MOSUM) of weighted residuals. We characterize the limit distribution of the test statistic and show that these tests are consistent. Moreover, we also obtain and tabulate the asymptotic critical values of the tests. Finally, we study the speed of detection under different conditions. The methods are illustrated and compared in several simulations.     

Bayesian analysis of linear models exhibiting changes in mean and precisionat an unknown time point

This paper analyses a linear model in which both the mean and the precision change exactly once at an unknown point in time. Posterior distributions are found for the unknown time point at which the changes occurred and for the ratio of the precisions. The Bayesian predictive distribution of k future observations is also derived. It is shown that the unconditional posterior distribution of the ratio of precisions is a mixture of F-type distributions and the predictive distribution is a mixture of multivariate t distributions.     

On control charts for monitoring the variance of a time series

In this paper we derive control charts for the variance of a Gaussian process using the likelihood ratio approach, the generalized likelihood ratio approach, the sequential probability ratio method and a generalized sequential probability ratio procedure, the Shiryaev–Roberts procedure and a generalized modified Shiryaev–Roberts approach. Recursive presentations for the calculation of the control statistics are given for autoregressive processes of order 1. In an extensive simulation study these schemes are compared with existing control charts for the variance. In order to asses the performance of the schemes both the average run length and the average delay are used.