教师职业生涯高原结构模型的建构

教师职业生涯高原是教师在其职业生涯发展的某一阶段中出现的职业进步如晋升、流动等的停滞所引发的心理与行为状态。它与教师个体的职业经历有着必然的联系。通过对中小学教师的开放式问卷调查结果的编码分析，揭示出教师职业生涯高原是由内容高原、趋中高原和层级高原及其子系统组成的一个多维度、多层次的结构系统。     

A note on replacement policy comparisons from NBUC lifetime of the unit

Age and block replacement policies are commonly used in order to reduce the number of in-service failures when the systems are functioning indefinitely. In reliability theory, the lifetime of a system can be modeled by means of the NBUC aging class that is characterized throughout comparisons of the residual lives in the sense of the icx order. The purpose of this paper is to establish stochastic comparisons between the age (block) replacement policy and a renewal process with no planned replacements when the lifetime of the unit is NBUC. Supported by Ministerio de Ciencia y Tecnología under grant BFM2000-0362     

高校精品课程资源建设支撑平台的研究与实践

针对鲁东大学在精品课程资源建设过程中遇到的具体问题和需求,采用J2EE技术,基于Web应用框架设计开发了高校精品课程资源建设支撑平台并付诸实践.对该支撑平台的设计思想与原则、子系统的划分与功能模块设计、系统架构与运行环境及应用情况进行了介绍.     

J2EE模型中Struts框架技术的研究和探讨

本文简要介绍了J2EE技术及其应用程序架构的发展,论述了Struts框架的基本设计思想,对应用Struts框架开发WEB应用做了一些研究和探讨。     

Optimal designs in random coefficient cubic regression models

In this article we investigate the problem of ascertaining A- and D-optimal designs in a cubic regression model with random coefficients. Our interest lies in estimation of all the parameters or in only those except the intercept term. Assuming the variance ratios to be known, we tabulate D-optimal designs for various combinations of the variance ratios. A-optimality does not pose any new problem in the random coefficients situation.     

On the consistency of MLE in finite mixture models of exponential families

Finite mixtures of densities from an exponential family are frequently used in the statistical analysis of data. Modelling by finite mixtures of densities from different exponential families provide more flexibility in the fittings, and get better results. However, in mixture problems, the log-likelihood function very often does not have an upper bound and therefore a global maximum does not always exist. Redner and Walker (1984. Mixture densities, maximum likelihood and the EM algorithm. SIAM Rev. 26, 195–239) provide conditions to assure the existence, consistency and asymptotic normality of the maximum likelihood estimator.     

A method for screening active effects in supersaturated designs

A supersaturated design (SSD) is a design whose run size is not enough for estimating all the main effects. The goal in conducting such a design is to identify, presumably only a few, relatively dominant active effects with a cost as low as possible. However, data analysis of such designs remains primitive: traditional approaches are not appropriate in such a situation and several methods which were proposed in the literature in recent years are effective when used to analyze two-level SSDs. In this paper, we introduce a variable selection procedure, called the PLSVS method, to screen active effects in mixed-level SSDs based on the variable importance in projection which is an important concept in the partial least-squares regression. Simulation studies show that this procedure is effective.     

琦君思乡怀人散文研究

琦君以其饱含深挚淳朴感情的笔触抒写了对故乡风物人情的眷恋,从真、善、美的视角叙写了自己的童年生 活见闻,心怀深深的敬意追忆着对自己谆谆教诲的恩师。这些,把读者带入了她那透露着深沉亲情乡愁的思乡怀人散文 之中,使我们体味到美的情感,也是她的散文的价值之所在。     

EJB技术在人力资源管理系统中的应用

以银行人力资源管理系统为研究背景,介绍了EJB技术的基本概念,分析了EJB组件模型的体系结构、技术特点及应用.     

伍德沃德-霍夫曼规则来源之争

简要介绍了美国化学家E.J.科里(E.J.Corey,1928-)对伍德沃德-霍夫曼规则(Woodward-Hoffmann rules)来源优先权之争的来龙去脉以及R.霍夫曼(Roald Hoffmann,1937-)对昔日往事的回顾,有助于理解伍德沃德-霍夫曼规则来源之争.