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1.
Financial stress index (FSI) is considered to be an important risk management tool to quantify financial vulnerabilities. This paper proposes a new framework based on a hybrid classifier model that integrates rough set theory (RST), FSI, support vector regression (SVR) and a control chart to identify stressed periods. First, the RST method is applied to select variables. The outputs are used as input data for FSI–SVR computation. Empirical analysis is conducted based on monthly FSI of the Federal Reserve Bank of Saint Louis from January 1992 to June 2011. A comparison study is performed between FSI based on the principal component analysis and FSI–SVR. A control chart based on FSI–SVR and extreme value theory is proposed to identify the extremely stressed periods. Our approach identified different stressed periods including internet bubble, subprime crisis and actual financial stress episodes, along with the calmest periods, agreeing with those given by Federal Reserve System reports.  相似文献   
2.
The generalized half-normal (GHN) distribution and progressive type-II censoring are considered in this article for studying some statistical inferences of constant-stress accelerated life testing. The EM algorithm is considered to calculate the maximum likelihood estimates. Fisher information matrix is formed depending on the missing information law and it is utilized for structuring the asymptomatic confidence intervals. Further, interval estimation is discussed through bootstrap intervals. The Tierney and Kadane method, importance sampling procedure and Metropolis-Hastings algorithm are utilized to compute Bayesian estimates. Furthermore, predictive estimates for censored data and the related prediction intervals are obtained. We consider three optimality criteria to find out the optimal stress level. A real data set is used to illustrate the importance of GHN distribution as an alternative lifetime model for well-known distributions. Finally, a simulation study is provided with discussion.  相似文献   
3.
Acculturative stress in the adjustment of immigrant families   总被引:1,自引:0,他引:1  
This study reviews the issue of acculturative stress in immigrant families. Acculturative stress includes behaviors experienced by immigrants that are a direct consequence of the process of acculturation and adaptation to a new society. A number of stressors impacting on the acculturation of immigrant families is discussed. These stressors include lack of English language skills, employment and economic status, educational background, family life, and sociopolitical and immigration status.  相似文献   
4.
This study examined variations in the relationships among child characteristics, parenting stress, and parental involvement. Participants were 100 two‐parent families with preschool‐aged children. Self‐report and interview data were collected to measure parental involvement, as well as perceptions of child temperament and parental stress. Analyses revealed significant, yet somewhat different, associations between child temperament and parental stress for mothers and fathers. More significant associations were found between perceptions of child temperament and involvement for fathers than for mothers. The associations between child temperament and parental stress and involvement differed on the basis of child and parent gender. Results are discussed in terms of future research on father involvement, as well as programs designed to encourage fathers to assume more active parental roles.  相似文献   
5.
The construct, family resilience, has been defined and applied very differently by those who are primarily clinical practitioners and those who are primarily researchers in the family field. In thisarticle, the family resilience perspective is integrated with conceptual definitions from family stress theory using the Family Adjustment and Adaptation Response (FAAR) Model in an effort to clarify distinctions between family resiliency as capacity and family resilience as a process. The family resilience process is discussed in terms of (a) the meaning of significant risk exposure (vs. the normal challenges of family life) and (b) the importance of making conceptual and operational distinctions between family system outcomes and family protective processes. Recommendations for future family resilience research are discussed.  相似文献   
6.
植物液泡膜H+-ATPase及其在胁迫中的响应   总被引:4,自引:0,他引:4  
V-ATPase存在于所有已知的真核生物中,在植物的生长、发育、信号转导和胁迫适应过程中发挥着重要的作用.近年来对V-ATPase的结构、功能和调节机制的研究进展较快,V-ATPase主要亚基已经完成序列测定及分析,并对各亚基生理功能、V-ATPase全酶复合体的组装、调控也有了较为深入的研究.该文在阐述植物细胞液泡膜H -ATPase的基本结构的基础上,介绍V-ATPase亚基组成、编码基因及在胁迫应答中的响应.  相似文献   
7.
受内压圆柱筒体开孔-接管区应力集中的有限元分析   总被引:4,自引:1,他引:3  
利用 ANSYS有限元分析软件通过三个算例对圆柱形筒体小开孔直接管区、大开孔直接管区、大开孔斜接管区的应力分布状况进行了研究 .从中了解到了最大第一主应力的变化规律 ,得出在弹性范围内的应力集中系数 ,并且得到ASME规范中的算式较好的验证  相似文献   
8.
英语单词重音位置的探讨   总被引:1,自引:0,他引:1  
英语单词的重音位置不同于法语、波兰语等重音固定于几乎所有单词的某个位置上 ,英语单词的重音位置受到许多因素的影响 ,并出现了很多由此而产生的重音理论和方法。依据词根、词缀和生成音位理论来分析单词重音的位置测定 ,发现单词重音位置的一般规律 ,并总结出英语单词的重音和构词间存在着密切的关系是文章的主旨。  相似文献   
9.
文章从素质教育的角度出发,通过分析当前师范院校中所存在的一部分教师在教学过程中忽视基本概念的教学的现象,指出了这种现象产生的原因和由此产生的严重后果。从理论上阐述了高等师范院校更应重视学科基本概念教学的必要性和重要性,同时,也提出了作为高等师范院校的教师在概念教学中所应具备的态度和应掌握、熟悉的多种概念教学的有效方法。为目前高等师范院校开展的课程体系和教学内容以及教学方法的改革提供参考。  相似文献   
10.
Although the health-enhancing effects of physical exercise have been well documented, less is known about how exercise benefits stressed employees psychologically. This article examines exercise as a coping response, and identifies changes in self-schemata (a person's underlying belief systems about him or herself) as the means by which exercise affects coping resources. In addition, by drawing on schema theory and the exercise literature, the active components of an exercise programme and the individuals who might enhance their ability to cope with stress through such a programme are identified.  相似文献   
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