高三复习前要做好的三件事

高考复习是一个系统工程,每一个环节要精心筹划,落实到位,才能收到良好的效果.文章深入分析了高三复习前要做好的三件事,研究考纲,明确方向;研究考题,预测命题趋势;研究学情,正确定位。这对每一位高三教师进行高三复习具有指导意义。     

家庭文化资本对学生学业成绩的影响及对策研究——基于石河子市某初中的调研

家庭文化资本不但是家庭社会地位的象征,还是影响家中子女学业成就获得的关键因素。为了深入了解家庭文化资本对学生学业成绩的影响状况,本研究选取石河子市某初中学校,按照分层抽样的方法选取229名学生作为被试,采用自编的《家庭文化资本问卷》,探求初中生家庭文化资本与其学业成绩的关系。结果显示,石河子市初中生家庭文化资本对学生学业成绩的有极其显著的正向影响,家庭文化氛围、父母和学生本人对学生将来学历的期望对学生学业成绩有显著的正向影响。     

基于新课程理念的数学课堂教学预设与生成的和谐构建

凡事预则立,不预则废,教学也如此。众所周知,无论教学设计多么周密,教学过程中总会出现很多预想不到的"可能",如果教师能冷静处理这些意外,跳出预设的思路,及时调整,顺应学生的思路,尊重学生的发现,使学生在参与和感受"问题解决"的过程中,既长知识,又长智慧,这才是本体意义上的数学学习。本文通过讨论怎样让"预设"和"生成"和谐,寻找使课堂教学达到最佳的效果。     

中学学习型教师团队建设探索——以华山中学为例

学习型组织具有五个要素,即自我超越、改善心智模式、建立共同愿景、团队学习、系统思考,学习型教师团队同样要符合这些特征。为此,华山中学开展了积极探索,提出创建学习型教师团队的关键是:建立共同愿景,提升生命力;改变学习方式,增强学习力;变革管理模式,培养创造力。初步营造出了凝心聚力实现又好又快发展的良好教育氛围,促进了学校教育实践的全面开展。     

Choosing arrival process models for service systems: Tests of a nonhomogeneous Poisson process

Service systems such as call centers and hospital emergency rooms typically have strongly time‐varying arrival rates. Thus, a nonhomogeneous Poisson process (NHPP) is a natural model for the arrival process in a queueing model for performance analysis. Nevertheless, it is important to perform statistical tests with service system data to confirm that an NHPP is actually appropriate, as emphasized by Brown et al. [8]. They suggested a specific statistical test based on the Kolmogorov–Smirnov (KS) statistic after exploiting the conditional‐uniform (CU) property to transform the NHPP into a sequence of i.i.d. random variables uniformly distributed on [0,1] and then performing a logarithmic transformation of the data. We investigate why it is important to perform the final data transformation and consider what form it should take. We conduct extensive simulation experiments to study the power of these alternative statistical tests. We conclude that the general approach of Brown et al. [8] is excellent, but that an alternative data transformation proposed by Lewis [22], drawing upon Durbin [10], produces a test of an NHPP test with consistently greater power. We also conclude that the KS test after the CU transformation, without any additional data transformation, tends to be best to test against alternative hypotheses that primarily differ from an NHPP only through stochastic and time dependence. © 2014 Wiley Periodicals, Inc. Naval Research Logistics 61: 66–90, 2014     

Some aging properties of parallel and series systems with a random number of components

In this article, we study aging properties of parallel and series systems with a random number of components. We show that the decreasing likelihood ratio property is closed under the formation of random minima. We also show, by counterexamples, that other aging properties are not closed under the formation of random minima or maxima. Some mistakes in the literature are corrected. © 2014 Wiley Periodicals, Inc. Naval Research Logistics 61: 238–243, 2014     

Some comparisons of residual life of coherent systems with exchangeable components

Most of the research, on the study of the reliability properties of technical systems, assume that the components of the system operate independently. However, in real life situation, it is more reasonable to assume that there is dependency among the components of the system. In this article, we give sufficient conditions based on the signature and the joint distribution of component lifetimes to obtain stochastic ordering results for coherent and mixed systems with exchangeable components. Some stochastic orders on dynamic (or conditional) signature of coherent systems are also provided. © 2014 Wiley Periodicals, Inc. Naval Research Logistics 61: 549–556, 2014     

Counterinsurgency American style: Considering David Petraeus and twenty-first century irregular war

This article examines the complex legacy of David Petraeus who was a key figure in the emergence of the US military shift towards counterinsurgency doctrine in the years after 2006. Although Petraeus has been perceived by critics as a publicity seeker, he can be credited with laying the foundations for a more serious commitment to COIN involving in particular in integrating conventional and Special Forces in arenas like village stability operations. The article looks a Petraeus's role in both Iraq and Afghanistan: it concludes that, in the case of Afghanistan, it is too early to assess whether counterinsurgency has had a decisive impact of the outcome of the war against the Taliban.     

卫星导航系统的体系安全性分析方法

为了应对卫星导航系统内部复杂关系等体系特征为其安全分析带来的挑战、全面识别和分析卫星导航系统面临的体系安全威胁、提高系统的安全性和服务能力,基于功能依赖网络分析理论提出了从体系角度研究卫星导航系统安全性的建模方法,重点对导航系统内组件系统之间交互关系导致的危险传播、任意失效组合进行了后果分析和原因调查。仿真结果表明该方法能清晰地描述危险传播和失效组合的过程以及进行正逆向的推理分析,也证明了该方法在卫星导航系统安全分析问题上的潜力和适用性。