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21.
采用计算流体动力学的方法,利用STAR-CCM+软件对某一车型挡风玻璃除霜性能进行数值模拟分析。通过对出风口格栅进行调整,改变了暖风气流与挡风玻璃之间碰撞角的大小与碰撞点的位置,优化了挡风玻璃表面暖风气流的分布,提升了除霜性能,为汽车除霜风道的设计和改善车辆除霜性能提供了参考。  相似文献   
22.
Children from families of low socioeconomic status (SES) tend to experience lower academic achievement than children from middle-SES families. This discrepancy can be attributed to a range of parental factors. The present study tested: (1) the extent to which academic achievement in three core subjects differs between children from low- and middle-SES backgrounds; (2) the differences in parental expectation, parental involvement, and child engagement across the two groups; and (3) the mediating role of parental expectation, parental involvement, and child engagement in explaining how SES influences children’s academic achievement. The sample consisted of 184 primary students with low SES and 165 primary students with middle SES from mainstream primary schools in Hong Kong. Results revealed significant differences in parental expectation, parental involvement, child engagement, as well as academic achievement in Chinese and English subjects between the low-SES and middle-SES groups. Our findings also suggest that parental expectation, parental involvement, and child engagement may be important mediators in the relationship between SES and academic achievement.  相似文献   
23.
Firms are increasingly relying on business insights obtained by deploying data analytics. Analytics-driven business decisions have thus taken a strategic imperative role for the competitive advantage of a firm to endure. The extent and effectiveness through which business firms can actually derive benefits by deploying big data-based practices requires deep analysis and calls for extensive research. This study extends the big data analytics capability (BDAC) model by examining the mediatory effects of organizational culture (CL) between internal analytical knowledge (KN) and BDAC, as well as the mediating effects of BDAC between CL and firm performance. The findings bring into focus that CL plays the role of complementary mediation between BDAC and KN to positively impact firm performance (FP); BDAC also plays a similar mediatory role between CL and the performance of a firm.  相似文献   
24.
ABSTRACT

Meta-analytic evidence supports that exercise has benefits for short-term memory (STM) and long-term memory (LTM). However, only three studies with children have tested the differential effects of exercise on STM and LTM. The purpose of this study was to examine the effects of an aerobic fitness test on STM and LTM and to consider the moderating effects of grade level. Children (7–13 years of age) were randomly assigned to either perform an aerobic fitness test before (exercise prior) or after (exercise post) performing the Rey Auditory Verbal Learning Test (RAVLT) to assess memory. Memory was tested again after approximately 24 hours. There were significant differences in memory performance as a function of grade with 4th and 6th graders consistently outperforming 2nd graders. For learning, Day 1 Retention, 24-hr recall, and Day 2 Retention, the exercise prior group performed better than the exercise post group. It is concluded that an aerobic fitness test performed prior to a declarative memory test benefits LTM as compared to when the aerobic fitness test is performed after the memory test.  相似文献   
25.
While there is a growing body of work that examines disciplinary identity development, unlike qualitative work in this area, quantitative research has not fully incorporated the importance of different contexts, nor has it uniquely focused on underrepresented groups (in this case, women in physics). This study examines how the constructs posited by prior work as important for physics identity, as well as an additional theorized construct, may interrelate and affect female students' physics identity differently depending on the context. Context in this study refers to two different experiential levels in college. The constructs examined include performance/competence, recognition, and interest, as well as sense of belonging. In particular, we used structural equation modeling to examine the effect that these constructs have on the physics identity of two groups of female physics undergraduates: first year students and senior year students. The results reveal that the relationship of the theorized constructs with physics identity vary between the two groups as well as compared to prior research with broad college student populations (not just physics majors). Unlike broad college student populations, for our sample of female physics undergraduates, interest did not have a direct effect on physics identity while sense of belonging was significant only for senior year students. These results exemplify the importance of examining context or different types of student experiences when studying disciplinary identity development rather than generalizing previous frameworks to all contexts.  相似文献   
26.
The study focuses on the research performance of Double First-Class (DFC) universities in China. A theoretical framework based on economic theory and the Analytic Hierarchy Process (AHP) method for a novel evaluation model is proposed. The model is performed on a sample of 41 participant DFC universities in China. Using data collected from these universities, it was found that there is no consistency between performance ranking, input ranking, and output ranking, with the best ranked universities far from the most efficient. These findings provide empirical evidence of DFC universities’ research performance situation and suggest strategies that the government can use to propel their sustainable development.  相似文献   
27.
督导作为一种人本主义管理思想和方法,是管理科学发展到一定阶段才出现的。将督导方法用于高校的绩效管理和监控工作中,既是对企业绩效监控的超越,也是绩效监控方式和观念的新发展。高校实行绩效管理的成功保障便在于建立完善的督导体系,明确绩效督导的内容,并按照督导逻辑付诸实施。  相似文献   
28.
根据景观小品设计的市场需要,有必要对景观小品设计表现进行研究,通过分析景观小品设计的必要性、要求、设计内容及各种表现形式,以提高人们对景观小品设计及表现的认识和理解,扩大该行业的社会影响。  相似文献   
29.
产权视角下农村土地流转机制的运行绩效研究   总被引:1,自引:0,他引:1  
土地是农民谋生的主要手段,土地制度是农村的基础制度。伴随着从计划经济体制向市场经济体制的转轨,农村土地产权的明确界定和保护越来越受到重视,各地也进行了不少探索和创新。文章将在产权理论尤其是产权对经济绩效的影响机制这个理论框架基础上,对我国农村土地流转机制中存在的问题进行分析,进而找到解决相关问题的途径,完善我国的农村土地流转,促进土地这一重要生产要素充分发挥它的经济职能,挖掘我国经济发展中蕴藏在农村经济体中的经济增长潜力。  相似文献   
30.
在世界各国采取节能减排行动的形势下,我国加快了清洁能源汽车的推广。发展天然气汽车产业对我国极其重要,未来国内外天然气汽车市场非常庞大,发展前景光明。我国汽车产业已形成了一定的国际竞争力,在未来的国际竞争中将获得更大的利益。虽然我国天然气汽车产业起步晚,但是起点高,有竞争力。为进一步发展天然气汽车产业,探索了发展我国天然气汽车的对策。  相似文献   
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