Heart rate and match analysis in pre-pubescent soccer players

The aim of this study was to compare match analysis (using video recordings) and the physiological load (heart rate measured every 5s, blood lactate measured after the warm-up, first half and second half) of six 11-year-old soccer players during official games of eleven-a-side on a regular-sized pitch (100×65m) and of seven-a-side on a smaller pitch (60×40m). In both games, heart rate exceeded 170 beats·min-1 84% of the time, while blood lactate ranged from 1.4 to 8.1 mmol·l-1 . No significant differences were recorded for the physiological parameters. For both matches, walking comprised 38% of total time, running 55%, inactivity 3% and jumping 3%. Although there were no significant differences between halves or matches, running for less than 10s was 10% more frequent in the seven-a-side game. In the seven-a-side game, there were significantly more passes and significantly fewer tackles, suggesting that seven-a-side matches played on smaller pitches may be more suitable for pre-pubescent soccer players.     

007詹姆士·邦德的身体政治研究

007系列电影因它的长盛不衰创造了电影史上的奇迹.一直以来,人们追捧它只因它提供的轻松娱乐.然而,随着文化研究在西方的蓬勃发展,越来越多的学者意识到不能把这种通俗文化看作理所当然.这类通俗文化,例如007,因其广泛的观众基础与偶像效应,在构建话语权威与实施文化霸权方面有着其不容忽视的威力.通过电影传播的知识结构也就更值得注意.文章着重探究邦德的身体构建以及他背后的身体政治.权力作用于身体有两种方式:以碎片拼凑塑造身体和赋予身体以含义.此外,邦德的不死之迷也透露了解构两个身体的必要性.     

掺铒聚合物光纤放大特性的理论分析

本文主要利用三能级系统的速率方程对掺铒聚合物光纤激光放大器的放大特性进行数值分析.从理论上模拟得到所研究光纤的最佳长度,并分析了在不同参数情况下,信号增益与泵浦功率的相互关系.     

含无辐射过程四能级GSA／ESA上转换发光的理论分析

不同于通常的三能级GSA／ESA上转换系统,给出了一个包含无辐射弛豫过程的四能级上转换系统,利用速率方程模型,从理论上分析了其上转换动力学过程和发光特性．结果表明,体系上转换的上升过程由所包含能级的无辐射弛豫速率决定,而衰减过程主要由终态能级的弛豫速率决定．     

A quantum chemistry study on reaction mechanisms of SO2 with O3 and H2O2

Reaction mechanisms of SO2 with O3 and H2O2 were investigated using quantum chemistry ab initio methods. Structures of all reactants, products, and transition states were optimized at the B3LYP/6-311G＋（3df,2p） level, and energy calculations were made at the G2M level. SO2 reactions with O3 and H2O2 occurred by O-abstraction and OH-abstraction by SO2, respectively, at length forming SO3＋O2 （3Eg） and H2SO4. For SO2＋O3 reactions the barrier height was predicted to be 9.68 kcal/mol with a rate constant of 3.61 × 10^-23 cm^3/（molecule.s） at 300 K, which is below the experimental upper limit. The rate constant predicted for this reaction accords well with the one provided by National Institute for Standards and Technology （NIST） in 250-500 K. For SO2＋H2O2 reactions the barrier height was predicted to be 62.39 kcal/mol with a rate constant of 2.48× 10^-61 cm^3/（molecule.s） at 300 K.     

企业退休职工养老金制度的改革

本文在合理的简化假设下,用logistic模型预测出山东省职工未来的年平均工资.继而由某企业2009年各年龄段月平均工资结合全省职工的年平均工资增长率,估算出未来该企业各个年龄段的月平均工资.根据养老金的计算方法,我们分别建立了刚退休时养老金的计算模型、退休若干年后养老金的收支平衡模型,分析出不同缴费情况下养老金的替代率、养老金的收支平衡与缺口情况,最后提出了既达到目标替代率又收支平衡应采取的措施.     

浅谈降低接地装置接地电阻的几种措施

根据通信电力网中接地引起的电网事故,就降低接地装置的接地电阻进行了探讨,并提出了建设性意见.     

中国图书情报学机构学术影响力研究报告——基于2003—2007年CNKI的统计分析

论文通过<中国知识资源总库>中的<中国期刊全文数据库>和<中国引文数据库>对2003-2007年图书情报学机构所发表的论文及其成果被引的统计数据进行分析,以衡量各机构在图书情报学研究领域的学术影响力.     

城市供水管网漏损原因探析

我国城市供水管网漏损现象严重,管网的漏损率已成为衡量供水企业现代化管理水平的重要指标.文章在系统分析供水管网漏损的主要原因基础上,提出了相应的改进措施,为城市节水防漏提供了一些方法.     

Bond graph based sensitivity and uncertainty analysis modelling for micro-scale multiphysics robust engineering design

Components within micro-scale engineering systems are often at the limits of commercial miniaturization and this can cause unexpected behavior and variation in performance. As such, modelling and analysis of system robustness plays an important role in product development. Here, schematic bond graphs are used as a front end in a sensitivity analysis based strategy for modelling robustness in multi-physics micro-scale engineering systems. As an example, the analysis is applied to a behind-the-ear (BTE) hearing aid.By using bond graphs to model power flow through components within different physical domains of the hearing aid, a set of differential equations to describe the system dynamics is collated. Based on these equations, sensitivity analysis calculations are used to approximately model the nature and the sources of output uncertainty during system operation. These calculations represent a robustness evaluation of the current hearing aid design and offer a means of identifying potential for improved designs of multiphysics systems by way of key parameter identification.