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941.
Although the engagement of grandparents in grandchildren’s life has increased, there is a lack of research that explores the values that grandparents desire to transmit to their grandchildren. The aim of this study was to analyze the factor structure, the validity, and the reliability of the Values Aspired for the Future Scale in a sample of grandparents. Three hundred grandparents participated in this study. Confirmatory factor analysis showed a three-factor structure with an excellent overall fit: personal and relationship values, abilities and knowledge values, and materialistic values. Grandparents’ sex did not have a moderating effect on the factor structure. An adequate internal consistency was obtained. Signi?cant associations between values, health-related quality of life, social support, and psychological well-being were found, with the exception of the materialistic values. This scale should be tested in different cultural contexts in order to confirm the results found. The implications of the results are discussed.  相似文献   
942.
Enactment of federal educational policy has direct implications for states and local school districts across the nation, particularly in the areas of accountability and funding. This study utilized constructivist grounded theory to examine the impact of policy on science education reform in a large, urban school district over a 5-year period. The existence and interaction between macro and micro, and explicit and implicit policies created educational turbulence. Findings further extend upon Fullan’s (Change theory: a force for school improvement, 2006) change theory adding high-stakes accountability as a prevalent distractor issue and the need for quad-level, rather than tri-level engagement in reform. Suggestions for addressing educational turbulence are provided.  相似文献   
943.
This meta-analysis investigated the maturation-related pattern of adaptations to resistance training in boy athletes. We included studies examining the effects of 4–16-week resistance training programmes in healthy boy athletes aged 10–18 years. Pooled estimates of effect size for change in strength across all studies (n = 19) were calculated using the inverse–variance random effects model for meta-analyses. Estimates were also calculated for groups based on likely biological maturity status (“before”, “during” and “after” peak height velocity). Using the standardised mean difference, resistance training increased strength across all groups (effect size = 0.98, [CI: 0.70–1.27]). Strength gains were larger during (1.11 [0.67–1.54]) and after (1.01 [0.56–1.46]) peak height velocity than before (0.5 [?0.06–1.07]). Adaptations to resistance training are greater in adolescent boys during or after peak height velocity. These findings should help coaches to optimise the timing of training programmes that are designed to improve strength in boy athletes.  相似文献   
944.
One component of the curriculum reform in Hong Kong focuses on the use of homework in consolidating learning, deepening understanding and constructing knowledge. This study examines the profile of Hong Kong primary school students' homework involvement, and investigates the relationships between time involvement and academic attributes, namely interest in homework, interest in academic subjects, academic efficacy, and efficacy for self-regulated learning. The sample comprised 2,361 primary school students representing all six grade levels in Hong Kong. Data was collected using questionnaires and homework diaries. Results showed heavy homework involvement among primary school students in Hong Kong, especially at the senior primary level. Differential patterns across levels were observed for the relationship between homework involvement and academic attributes. Specifically, junior primary students' study-related interests and efficacies were found to decline with increasing time involvement, whereas inverted U-shape relationships were observed among senior primary students. There was concern for students with high time involvement as they received more homework and they worked slower. They were less likely to perceive the positive functions of homework, and showed poorer study-related interests and efficacy beliefs. The findings of this study provide crucial information for school personnel and educators in Hong Kong in developing homework strategies and policies that enhance teaching and learning.  相似文献   
945.
Abstract

In an economic climate when colleges can no longer presume that legislators see institutions of higher learning as tacit public goods, institutions around the country are facing budget cuts. This article presents a case study of the experience of a mid-sized public state university and its Library in a budget crisis undergoing a university-wide program prioritization process. The authors review the process of writing three reports on the Library’s value, along with the approach to engaging staff in the process including a retreat. This article raises questions about what every library should consider assessing and provide tools for libraries navigating similar terrain.  相似文献   
946.
The existing studies on prescribed-time control cannot directly deal with nonlinear functions which don’t satisfy Lipschitz growth conditions. No results are available for prescribed-time containment control of pure-feedback UNMASs with prescribed performance. Therefore, completely unknown nonlinear function, prescribed-time tracking of system states and prescribed performance of containment errors are simultaneously considered in this paper. Fuzzy logic systems are utilized to approximate completely unknown nonlinear function. Prescribed-performance function is introduced and further incorporated into a novel speed function. Combining the proposed speed function and barrier Lyapunov function, this article presents a novel adaptive fuzzy prescribed-time containment control method which can guarantee, under prescribed performance, all followers converge to a convex formed by dynamic leaders in a prescribed time. Moreover, all tracking errors converge to predefined regions in a prescribed time. The effectiveness of the proposed prescribed-time containment control method are confirmed by strict proof and simulation.  相似文献   
947.
In this paper, we present a functional variable method for finding periodic wave and solitary wave solutions of complex nonlinear evolution equations in mathematical physics and engineering sciences. The proposed technique is tested on the generalized Zakharov equation and higher-order nonlinear Schrödinger equations. The method is straightforward and concise, and it can also be applied to other nonlinear evolution equations in applied mathematics.  相似文献   
948.
This is the third installment in Robert Berring's autobiography, The Education of a Twentieth Century Law Librarian. The first installment is at 32 Legal Reference Services Quarterly 1 (2013). The end of the traditional world of law libraries is chronicled through a study of the workings of the Harvard Law Library in the period 1978-1981. Computerized catalogs, changing styles of reference and difficult questions of management are explored. The painful transition that faced all libraries is discussed. This is the third installment of a five part series on the profound change in law libraries during this period.  相似文献   
949.
950.
关联规则挖掘是解决电子商务推荐问题的重要方法之一.针对传统关联规则挖掘算法在解决移动电子商务环境个性化推荐问题时反复扫描数据库,频繁项挖掘效率低,关联规则挖掘准确率低以及规则大量冗余等不足,提出一个基于事务矩阵和用户兴趣度的关联规则挖掘算法(Matrix-and-Interestingness-based Association Rules Mining,MIbARM).该算法仅需扫描一次数据库,并在挖掘过程中不断缩小算法搜索空间以避免生成冗余候选项,同时避免了冗余规则挖掘,从而提高了挖掘效率.最后,在四组人工数据和160种参数组合的数值实验环境下,引入Apriori、CBAR 及BitTableFI算法对MIbARM进行对比验证.结果表明,在不减少有趣规则的前提下,MIbARM不但可有效避免冗余候选项集的产生,而且大幅减少了冗余规则数量,极大提高了算法的搜索效率,同时提升了个性化推荐的质量,更适用于移动电子商务环境下的个性化推荐问题.  相似文献   
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