一类离散时滞随机系统的稳定性分析

针对一类不确定随机离散变时滞系统,建立了随机稳定性标准,该系统中随机干扰满足布朗运动。选取合适的李雅普诺夫函数,借助于随机稳定性理论、自由权矩阵和线性矩阵不等式等方法,给出并证明了使得该系统随机稳定的充分条件,所有结果以线性矩阵不等式的形式给出,应用例子和仿真表明所给稳定性标准的有效性。     

一个代数不等式的另类证明及其推论

利用排序不等式重证了一个代数不等式,并在此基础上得出了新的结论.     

From objects to subjects: Repositioning teachers as policy actors doing policy work

Within policy discourses, teachers are positioned as objects of reform who enact policies under rational systems of observation and accountability and are, therefore, situated as de-professionalized actors lacking expert knowledge. This research project asks relatively straight-forward questions: If practicing teachers were given a voice in political debates over urban education policy and reform, what would they say? What macro-level policy problems would they identify as being important? Findings indicate the primary policy problems include Systemic Inequity and Bad Policy. The primary policy solutions include, Schools as a Community Resource; Shared Decision-Making; Contextual Goals; and Time, Space and Resources.     

用概率论方法解决数学问题的若干实例

本文用概率论方法证明了数学分析中的若干恒等式和不等式，其中有些结果是新的。     

算子迹算术-几何平均不等式

利用泛函分析方法将半正定矩阵迹不等式|tr(A1A2…Am)|1m≤1m(trA1 trA2 … trAm)推广到Hilbert空间,并得到相应的正迹类算子不等式.     

半正定Hermite矩阵的一个不等式

设Aj,Bj∈Cn×n(j =1,2, ,m)为半正定Hermite矩阵 ,本文建立了下列不等式∏mj=1detAj·detBj (1mn)mn ∑mj=1tr(AjBj) mn     

论我国教育产业中的不公平问题

教育产业不公平是当前教育研究的热点教育产业中的一个新问题。由于教育产业不公平而带来的诸多教育问题已广为人们关注。为此，研究教育产业中的不公平问题就具有相当重要的意义。本从我国教育产业不公平的表现形式、原因分析及对策研究三个方面探讨了这一问题。     

对贝尔不等式的误解

贝尔对自己的工作有两点误解:第一,贝尔用以导出贝尔不等式的隐变量理论具有一个极为特殊的性质:它原封不动地保留了全部经典概率论的运算规则,贝尔却把这种理论当成一般的"定域隐变量理论";第二,当贝尔从他的隐变量理论导出贝尔不等式时应用了两个命题,他把其中之一理解为"定域隐变量理论"的特征,而实际上导出贝尔不等式的却是另一命题.在此试图说明,没有定域隐变量理论也能导出贝尔不等式.此外,还考察了吉.洛查克对贝尔定理的异议.     

涉及单形的中线长的两个几何不等式

本文给出涉及n维单形的中线长度的两个几何不等式,证明了苏化明所提的一个猜想(数学季刊4(1)(1989))是正确的,最后,还提出了一个猜想。     

Social support and digital inequality: Does Internet use magnify or mitigate traditional inequities in support availability?

This study tested competing predictions about the implications of Internet use for traditional inequities in social support availability. Using survey data collected as part of the Pew Internet and American Life Project, inequities in social support availability stemming from demographic and network-related factors were examined among non-users, Internet users, and Internet users who also participated in a social network site (SNS). The results offered evidence consistent with the social compensation perspective. Traditional inequities in support availability related to age, race, and total network size persisted among respondents who did not use the Internet, but were less evident or absent among Internet users and/or Internet users who participated in an SNS. Using the Internet to connect with others appeared to be an important mechanism through which inequality in support availability was mitigated.