Schwarz积分不等式在二元函数中的推广及应用

Schwarz积分不等式是一个重要的不等式,它在自然科学的理论研究以及实际应用中用途广泛.本文将Schwarz积分不等式推广到二元函数中,并给出一些应用.     

Community interaction and child maltreatment

The way in which parents interact with their environment may have implications for their likelihood of abuse and neglect. This study examines the parent–environment relationship through community involvement and perception, using social disorganization theory. We hypothesize mothers who participate in their communities and have positive perceptions of them may be less likely to maltreat their children because of the potential protective capacity of neighborhood supports. Using information from the 5 year Fragile Families and Child Wellbeing Study (n = 2991), the mother's self-reported acts of psychological and physical maltreatment and neglect are measured. A mother's community involvement index is the number of community activities a mother was involved in, and community perception is measured by two five-item Likert scales assessing perception of community collective efficacy. We analyze the relationship between community variables and each of mother's maltreatment behaviors as well as the interaction between community factors using a series of nested logistic regressions. Higher levels of community involvement are associated with lower levels of psychological aggression. More positive perception of community social control is associated with lower levels of physical assault. A moderation effect of community perception suggests that a mother's perception of her community changes the relationship between community involvement and psychological child abuse. The results provide important policy and empirical implications to build positive and supportive communities as a protective factor in child maltreatment. Getting parents involved in their communities can improve the environment in which children and families develop, and decrease the likelihood that maltreatment will occur.     

The effect of online co-regulated learning in the implementation of team-based learning on improving students’ involvement

Many education institutions and teachers are recognizing and applying online learning and related educational technologies to help students achieve satisfactory learning performance. Due to the free entertainment on the Internet that may distract students’ attention from online courses and with the purpose of developing students’ teamwork abilities, the author in this study adopted team-based learning (TBL) and co-regulated learning (CRL) to develop students’ involvement in a blended computing course. The subjects in this study were 111 first-year students from three classes taking a compulsory course titled ‘Applied information technology: data processing’. The first group (G1, which received online TBL and CRL) and the second group (G2, which received online TBL only) were the experimental groups. The last group (CG), which received the traditional teaching method in a blended learning environment, served as the control group. The results in this study indicate that students who receive the online TBL have significantly higher involvement than those without. However, the online CRL does not contribute to better development of students’ involvement in the implementation of TBL. The insights for teachers who plan to adopt e-learning, and the reasons for the ineffectiveness of CRL, are discussed in this study.     

Are boys that bad? Gender gaps in measured skills,grades and aspirations in Czech elementary schools

This article examines gender gaps in academic performance (grades in mathematics and reading) between boys and girls of ninth-grade elementary schools in the Czech Republic. Our analysis is based on 2003 data from the Programme for International Student Assessment, encompassing the academic performance and family background of ninth-grade pupils. Similar to research on other countries, we find that girls strongly outperform boys in grades in Czech language, but that this gender gap is not explained by measured ability in reading nor on family background or student attributes. We also find gender bias in mathematics grades, after controlling for measured ability and other factors. Girls are also substantially more likely than boys to apply to secondary grammar schools, as well as aspire to a college education, even after controlling for measured ability. We put forward a number of theoretical perspectives that shed light on the possible causes of these empirical findings.     

Reviewing the Family Unit as a Stakeholder in Talent Development: Is It Undervalued?

As elite youth sport becomes more organized and professionalized, the role of the family is increasingly acknowledged as being significant in the development of young talent. High-profile examples across a range of professional sports, both positive and negative, have drawn attention toward this important stakeholder. Accordingly, this review first examines the key issues in relation to family involvement in talent development in relation to what is perceived as good and bad practice on behalf of the family. Next the key theoretical underpinning is considered, Family Systems Theory, and how it may be integrated within elite youth sport. Finally, the article concludes with a summary of where the current literature leaves us and where we can progress from here. Two possible inputs are suggested that could benefit the effectiveness of family involvement: a focus on the family holistically and a second on the role different family members can play.     

Inequality in Ethiopian higher education: reframing the problem as capability deprivation

The revitalization of Ethiopian higher education (HE) has been underway since the early 2000s. As well as the economic optimism evident in the ‘knowledge-driven poverty reduction’ discourse, social equity goals underscore the reform and expansion of the system. Notwithstanding the widening participation and the equity policy provisions put in place, the problem of inequality has persisted along the lines of ethnicity, gender, rurality and socio-economic background. This paper reviews major equity policy instruments and highlights the enduring inequalities in Ethiopian HE. It argues that this persistence is related in part to the ways in which the problem is represented in policy, and that redressing the problem necessitates framing inequality as capability deprivation rather than as issues of access and disparities in enrolment.     

Residence-based priorities and school choice

Many countries use centralized school choice procedures to assign pupils to schools. To address excess demand for a particular school, ties are broken according to priority points granted based on various criteria, such as proximity to the school. Using a unique reform undertaken in Madrid (Spain), we estimate the impact of abolishing residence-based priorities on families’ school choices, the stated motivation for choosing a school, and the final school allocation. Utilizing several administrative datasets on school applications, we find that the reform increases families’ out-of-district school assignments and assignments to schools further away from their home address. Parents of immigrant children did not change their application behavior in the first years of the reform but caught up with natives three years after its implementation. Children generally accessed slightly better-performing schools, particularly those from lower-educated backgrounds.     

对河南省高级知识分子参与体育活动特征的研究

运用文献资料、调查访问、问卷调查法，对河南省部分城市高级知识分子参与体育活动的特征进行调查与分析。结果发现，高级知识分子参与体育活动的时间较短且强度低、频率低，参与体育消费的水平较低。建议相关部门应制订合理政策提高知识分子体育活动的参与性，加强大众传播媒体的宣传力度，完善体育设施及社会体育指导员体系，建立单项体育协会，营造良好的体育锻炼氛围。     

凝聚力对教练员领导行为、运动员角色投入和运动员满意度的中介作用

探讨我国高水平手球队凝聚力是否对教练员领导行为、运动员角色投入与运动员满意度具有中介作用。赛前使用群体环境问卷对160名参加全国女子手球锦标赛的运动员进行凝聚力测试，赛后使用运动领导行为量表、运动员角色投入问卷、运动员满意度问卷对上述运动员进行了测试。运用Baron和Kenny（1986）线性回归分析方法对凝聚力的中介作用给予检验。结果表明，运动员所知觉到的领导行为和角色投入对团队成绩满意度、团队一致满意度影响显著，但该影响由于凝聚力的加入而变小或变得不显著。说明凝聚力对领导行为、角色投入与团队成绩满意度、团队一致性满意度具有中介作用。     

区间广义系统的θ_∞鲁棒控制

首先讨论了非受限区间广义系统的容许性问题 ,用广义 Riccati不等式给出该系统容许的充要条件 ;再讨论了区间广义系统的鲁棒控制问题 ,并且用广义 Riccati不等式给出状态反馈下的闭环系统容许且传递函数矩阵的 H∞ 范数小于给定的正常数γ的充分条件 ,最后用数字例子来验证此方法的有效性