Peripheral Narrowing among Experienced and Inexperienced Rifle Shooters under Low- and High-Stress Conditions

Abstract

This study examined Easterbrook's (1959) hypothesis that performance on a primary task would improve or at least be maintained with increased levels of arousal, while performance on a secondary task would decrease. To test this hypothesis, the performance of 20 collegiate rifle shooters (10 experienced, 10 inexperienced) on a primary target shooting task and a secondary auditory task were compared while shooting under low- and high-time stress conditions. Heart rate results, but not a self-report anxiety measure, provided evidence for the effectiveness of the stress manipulation. The results primarily supported Easterbrook's hypothesis. There were no differences in secondary task performance between experienced and inexperienced shooters. However, subjects who first underwent high time stress followed by low (H-L) shot better than those given the reverse order (L-H). These findings are discussed in relation to the attention demands of self-paced sports as well as the transfer effects of stress.     

The relevance of innovative school architecture for school principals

In many cases, innovative forms of learning require innovative concepts of using space in school. However, so far there has been a lack of research concerning the perspectives of school principals as important stakeholders in the adoption of alternative school architecture. The present study examines the importance of alternative school architecture in a sample of 1164 principals (56% females, mean-age 52.7 years) in Austria. An online questionnaire was conducted, containing questions about the school building, innovative forms of learning, and principals’ level of information, perceptions, and thoughts on the relevance of school architecture, as well as their motivation and self-efficacy. Results showed that principals are aware of the advantages of certain architectural elements, although these elements have been implemented in only a few schools. A high proportion of respondents report a lack of information about configurations of space that go beyond the traditional corridor-scheme. We conclude that although principals are in general open for the alternative configuration of space further efforts have to be made to overcome the obstacles that prevent principals from launching new concepts of using space, which are a lack of competitive resources and knowledge as well as an inadequate professional network.     

WINDOWS95的启动模式与MSDOS.SYS文件设置

本文对WINDOWS95的不同启动模式作了全面介绍,并就WINDOWS95与WINDOWS3.X的共存、如何设置MSDOS.SYS文件实现不同的启动模式,优化WINDOWS95,充分发挥计算机资源提出见解。     

Bond strength improvement of GFRP rebars with different rib geometries

Based on the Canadian Standards Association (CSA) criteria,105 pullout specimens were tested to investigate the effect of different rib geometries on bond strength of glass fiber reinforced polymer (GFRP) rebars embedded in concrete. Two kinds of conventional reinforcing rebars were also studied for comparison. Each rebar was embedded in a 150 mm concrete cube,with the embedded length being four times the rebar diameter. The experimental parameters were the rebar type,rebar component,rebar diameter,rebar surface texture,rib height,rib spacing and rib width. Theoretical analysis was also carried out to explain the experimental phenomena and results. The experimental and theoretical results indicated that the bond strength of GFRP rebars was about 13%～35% lower than that of steel rebars. The bond strength and bond-slip behavior of the specially machined rebars varied with the rebar type,rebar diameter,rebar surface texture,rib height,rib spacing and rib width. Using the results,design recom-mendations were made concerning optimum rib geometries of GFRP ribbed rebars with superior bond-slip characteristics,which concluded that the optimal rib spacing of ribbed rebars is the same as the rebar diameter,and that the optimal rib height is 6% of the rebar diameter.     

空心加压螺钉不同构型固定股骨颈骨折的生物力学研究

目的:用力学实验的方法,对倒、正等腰三角形布局的三枚空心加压螺钉固定头颈型股骨颈骨折进行生物力学比较,确定哪种空间构型生物力学性能好,从而为临床治疗股骨颈骨折提供理论依据.方法:用生物力学机测试比较倒、正等腰三角形空间构型抗压、抗扭性能及最大垂直载荷,实验数据用SPSS10.0统计软件进行t检验,P＜0.05有显著性差异.结果:倒等腰三角形构型在抗压、最大垂直载荷方面优于正等腰三角形组,有显著性差别;抗扭转方面无显著性差别.结论:实验结论支持治疗头颈型股骨颈骨折三枚空心加压螺钉倒等腰三角形构型生物力学效果好.     

物流实验室的配置和建设

物流专业是培养具有管理、经济、工程、计算机等方面知识和能力，从事物流经营、运输、仓储、管理、决策、系统设计及教学科研的高层次复合人才。文章结合物流专业的特点，从指导思想、实验室布局、硬件配置、软件系统和实验内容等方面提出了物流实验室的配置方案，并对物流实验室建设问题进行了探讨。     

现代化实验室(大楼)建设中的配套问题

随着我国高等教育事业蓬勃发展，实验室(大楼)建设掀起新高潮，趋向现代化，起点和标准都大大提高，提出应重视在建设初期配套问题，如实验室布局、基础设施、技术条件等，使大投入产生大效益。     

基于语义web技术的定制产品配置知识建模

为成功实施大规模定制战略,研究解决了在语义层次建模产品配置知识的问题.结合语义web技术,提出了基于本体的配置知识建模方法.开发了通用配置本体为建模特定产品领域的配置知识和规则提供公共的概念结构,采用OWLweb本体语言和语义web规则语言(SWRL)形式化地表示了配置本体、领域配置知识和规则,以促进各种配置知识的一致性、可维护性和重用性.可定制的个人计算机族的配置知识建模说明了该方法能为特定的产品配置领域提供明确的、计算机可理解的知识语义,高效率地支持自动的复杂产品配置任务.     

‘Sitting alone in the staffroom contemplating my future’: communities of practice,legitimate peripheral participation and student teachers’ experiences of problematic school placements as guests

A recent Review of Teacher Education in Scotland reports that 23% of respondents (n = 2381) encountered variable or very poor school placement experiences. This paper uses Lave and Wenger’s ideas concerning Communities of Practice (1998) and Legitimate Peripheral Participation (1991) as analytical tools with which to understand the nature and impact of student teachers’ problematic experiences of school placement. A total of 14 Professional Graduate Diploma in Education students on a one-year Secondary English course were followed through the practice elements of their Initial Teacher Education programme and data were constructed from learning logs and semi-structured interviews. Analysis provided a nuanced account of the student teachers’ difficulties in attaining member status as Legitimate Peripheral Participants in communities of practising teachers, with the concepts ‘joint enterprise’, ‘mutual engagement’ and ‘shared repertoire’ being found to be useful in explaining these difficulties. Limitations in the theoretical framework were also discovered and these are highlighted and developed in the paper.     

对负反馈电路判断的探讨

负反馈在放大电路中被广泛采用,文章从反馈网络、反馈极性、反馈组态等方面对负反馈电路进行了分析,得出了判断负反馈的方法和技巧,最后以实例说明负反馈电路的应用.