Influence of upright versus time trial cycling position on determination of critical power and W′ in trained cyclists

Body position is known to alter power production and affect cycling performance. The aim of this study was to compare mechanical power output in two riding positions, and to calculate the effects on critical power (CP) and W′ estimates. Seven trained cyclists completed three peak power output efforts and three fixed-duration trial (3-, 5- and 12-min) riding with their hands on the brake lever hoods (BLH), or in a time trial position (TTP). A repeated-measures analysis of variance showed that mean power output during the 5-min trial was significantly different between BLH and TTP positions, resulting in a significantly lower estimate of CP, but not W′, for the TTP trial. In addition, TTP decreased the performance during each trial and increased the percentage difference between BLH and TTP with greater trial duration. There were no differences in pedal cadence or heart rate during the 3-min trial; however, TTP results for the 12-min trial showed a significant fall in pedal cadence and a significant rise in heart rate. The findings suggest that cycling position affects power output and influences consequent CP values. Therefore, cyclists and coaches should consider the cycling position used when calculating CP.     

新时期中国体育外交政策探析

2018年朝鲜成功开展一次体育外交行动参加韩国平昌冬奥会,向韩国政府表达出善意的政策倾向,朝鲜半岛的紧张局势也因此得到缓解,体育外交的政治收益又一次得到验证。以新时期体育外交为研究对象,采用文献资料法、逻辑分析法研究新时期开展体育外交活动的政治诉求,如何推动中国的外交事务和体育行业的发展。研究认为：体育外交能够以相抵柔和的方式表达政治意见或者政治态度;中国优秀传统文化、中国传统体育项目需要传承和发扬光大,需要适合根据国际文化变化做出调整,更需要加强对外交流;国家领导人或者体育明星在体育外交中塑造国家形象的功能不容小觑;积极培养能够在国际体育组织任职的人员、积极参与国际体育事物能够缓解中国在体育界话语权薄弱的问题。     

建设体育强国背景下体育经济重要地位及其发展策略

加快体育强国建设已成为一项国策,研究如何提高和建设可持续发展性的体育产业经济以解决人民日益增长的美好体育生活需要和不平衡不充分的发展之间的矛盾对建设体育强国具有重要意义。采用哲学辩证理论分析体育产业经济对体育强国构建的重要性,统计分析目前我国体育产业经济发展现状及其与发达国家的差距,结合十九大新时代背景下给出未来体育产业经济发展策略以期寻求为构建体育强国给出一些指导意见。认为：体育经济是体育强国的重要基石;开展全民健身运动、优化体育产业结构、政府政策导向市场化、跨产业融合增加与其他产业的结合度对构建体育强国具有重要的意义。     

基于他人伦理框架的体育治理研究

对体育治理实践展开伦理追问是促进体育治理发展的重要前提。体育治理他人所传达的内涵为社会与社会多元体育治理主体,据此,体育治理他人伦理问题有"相对他人"和"绝对他人"的二元面向:其一,应重视他人需要,基于伦理视角考量体育治理手段的正当性,对复杂体育治理关系包含的伦理意蕴加以反思;其二,确证社会多元体育治理主体的他人地位,认可并尊重他人的客观存在,与他人协同共治,并在体育治理中可以对他人负责。体育治理他人伦理的根基是诚实守信,目标导向为体育资源配置的公平公正,具体包括自我与他人的商谈伦理、责任伦理、制度伦理以及发展伦理。基于他人伦理框架研究体育治理问题的理论创新在于带来了一种新颖的交叉学科视角,实践价值在于为推进现代化的体育治理体系和治理能力建设带来了内生动力。     

Governing through guidance: an analysis of educational guidance practices in an Italian lower secondary school

ABSTRACT

Current social policy discourse defines educational and career guidance as a key tool to enhance individual self-realisation while pursuing collective social objectives (economic growth, reduction of drop-out rate, social inclusion). Relying on Foucault’s concept of governmentality, critical research has long destabilised this mainstream narrative by stressing that guidance polices constitute a technology of government through which the political ambition to govern is realised by shaping citizens’ desires and ambitions. This article aims to provide an in-depth empirical analysis of how governing practices unfold within a concrete guidance setting. Based on ethnographic data, the essay focuses on guidance practices addressing 13–14-year-old students in Italy moving from comprehensive education to a tracked educational level. Particular emphasis is given to the role played by guidance forms, questionnaires and exercises. These materials, it is argued, enable particular technologies of the self that are key to involving individual in practices of self-government.     

Probability Density Function Method for Observing Reconstructed Attractor Structure

Probability density function (PDF) method is proposed for analysing the structure of the reconstructed attractor in computing the correlation dimensions of RR intervals of ten normal old men. PDF contains important information about the spatial distribution of the phase points in the reconstructed attractor. To the best of our knowledge, it is the first time that the PDF method is put forward for the analysis of the reconstructed attractor structure. Numerical simulations demonstrate that the cardiac systems of healthy old men are about 6 - 6.5 dimensional complex dynamical systems. It is found that PDF is not symmetrically distributed when time delay is small, while PDF satisfies Gaussian distribution when time delay is big enough. A cluster effect mechanism is presented to explain this phenomenon. By studying the shape of PDFs, that the roles played by time delay are more important than embedding dimension in the reconstruction is clearly indicated. Results have demonstrated that the PDF method represents a promising numerical approach for the observation of the reconstructed attractor structure and may provide more information and new diagnostic potential of the analyzed cardiac system.     

转轨时期腐败问题的经济学分析

经济学是从资源配置和效率来阐述对一切行为的判断准则。本运用现代经济学的原理和方法来分析当前日益猖獗的腐败行为，对腐败产生的原因和危害以及腐败治理提供了经济学意义上的分析。     

客户集中度、关键客户议价力与中小企业绩效--基于中小企业板制造业上市公司的实证研究

基于交易费用理论与资源依赖理论,本文利用中国深圳证券市场中小企业板上市的制造业企业的数据,采用多元回归的方法研究客户集中度对中小企业绩效的影响。结果表明,中小企业客户集中度对企业绩效有显著正向作用;关键客户议价力在客户集中度与企业绩效间的关系中具有部分中介效应;企业产品类别在客户集中度与企业绩效的关系中具有调节效应：工业品制造企业的客户集中度对企业绩效具有显著的正向影响,但这种影响在消费品制造企业中并不显著存在。研究结果对中小企业的市场发展具有指导意义。     

基于PSO的电力系统环境经济负荷调度

针对基于线性加权和处理成单目标优化问题的传统方法存在的缺陷,提出使用粒子群优化算法求解EELD多目标优化问题。该方法通过对粒子群算法个体极值和全局极值选取方式的改进,实现了对EELD多目标优化问题的非劣最优解集的搜索,为决策者提供了丰富的参考信息。在此基础上,应用模糊满意度方法求出的最优折衷解为调度运行人员提供了最佳调度折衷方案。最后,对一个三机系统进行了测试,并与线性加权人工神经网络法进行了比较分析,仿真结果验证了该方法的有效性。     

家庭型酸奶工艺的探究

讨论了家庭型酸奶制备的基本工艺条件,分析了接种量、加糖量和发酵温度等发酵条件对酸奶质量的影响,同时对发酵剂的选择、连续转接后发酵剂的发酵力变化、连续转接酸奶的质量等问题作了研究。结果表明：家庭型酸奶制备时的发酵条件以接种量为7％、加糖量为5％为宜;室温达30℃左右即可满足家庭条件下酸奶发酵成功所需的温度;尽管连续转接后发酵剂的发酵力并没有明显降低的趋势,但连续转接酸奶的质量却有所下降。