基于泄漏量的消防水泵可靠性评估

基于状态维修(CBM, Condition Based Maintenance)方法是预防性维修方法的一种,它以比例风险模型(PHM,Proportional Hazard Model)为基础,强调运行时间和实时状态对设备运行寿命的影响,通过设备运行的历史数据和实时运行状态来评估其可靠性。本文在PHM模型的基础上,利用灰色模型估计模型中风险度函数的相关参数,使之适应于消防水泵失效数据较少的情况,提出了适应小样本数据的设备状态评估方法。并以实际使用的消防水泵泄漏量作为计算状态量,采用CBM方法计算了水泵的可靠度、风险度,计算结果显示该方法能够评估设备的运行状态,并能优化设备维修策略,节约维修成本。     

基于泛函分析的大学生体育舞蹈综合素质动态变化的量化评估模型

为了深入分析与评估大学生体育舞蹈综合素质变化情况,确立了一种用于系统化评估大学生体育舞蹈综合素质变化的整体思路,选择了评估参照信息并给出其测度方法;结合当代体育舞蹈特色确定了评估指标并给出评估指标的计算方法;随后,基于泛函分析方法建立了大学生体育舞蹈综合素质动态变化的评估模型,说明了模型的功能及使用方法,以湖南商学院为例进行评估实验验证了本文方法可行性、实用性、有效性。     

关于基坑变形预测方法的优化研究

神经网络算法的收敛性和稳定性已经得到了广泛的证明,被应用在许多工业监控场合,在传统的BP神经网络预测基坑变形方法的基础上,融入了灰色算法,生成了一种新的智能化模型,以对原有方法进行优化。通过实际案例证明,新的组合模型无论在计算时间还是在计算精度方面,都显示了较为明显的优势,具有一定的经济意义和实用价值。     

大学生国家体育锻炼标准计分方法的探讨

将现在执行的大学生国家体育锻炼标准采用的分档计分法改进为对应计分法,给出了对应计分法对于不同项目计算得分的计算公式和等级评定标准,结合应用给出了对应计分法的计算模型和计算例。     

运动训练控制领域中的灰色系统模型分析

采用数理统计方法及例证等,介绍了在运动训练控制领域中灰色系统模型分析方法的运用。在运动训练领域中,灰色关联模型分析可以用于运动员的选材和各训练指标的权重值计算;灰色协调模型可以用于竞技实力的强、弱项分析以及各训练指标值的调控;灰色预测模型可以预测未来的比赛成绩。运用于运动训练领域中的多种灰色系统模型分析方法,能够较为科学地为运动训练控制过程的实施提供参考。     

人体有限块刚体模型的动力学计算

在运动生物力学许多问题的研究中,可以将人体简化为若干块刚体用铰链连接的多刚体系统。通常可采用图一所示的十五块刚体模型,但在有些情况下也可取多于或少于十五块的模型。我们利用R.Huston等人介绍的多刚体系统动力学的方法,建立人体模型的动力学方程组,并编制了适用于人体有限块刚体模型的动力学计算程序,可对人体腾空及单点支撑(或悬垂)的各种动作进行动力计算。经若干算例验证,该程序是有效的。     

降雨衰减及去极化效应

研究了降雨引起的衰减与去极化效应,根据ITU-R提出的雨衰减预报模型,计算了我国某些城市的地空雨衰减量。将离散雨介质视为一随机系统,利用系统辨识的方法,利用系统辨识的方法,结合某市实验数据得到了一个去极化分辨率的序列模型。     

体育教师综合素质动态量化评估模型的构建与应用

根据体育教师综合素质变化情况,确立了一种用于系统化评估的整体思路,选择了评估参照信息并给出其测度方法;结合当代体育教育对教师综合素质需求确定了评估指标并给出评估指标的计算方法;基于测度论建立了教师综合素质动态量化评估模型,以湖南商学院、国防科技大学为个案进行评估实验,说明方法的有效性.     

一种优选法在集体项目比赛中的应用

在集体项目比赛中,为了能够较为合理地选派上场队员,本文列举一种优选方法,该方法能在较复杂的情况下帮助决策者正确地作出决策。文中给出了该方法的原理、模型及计算步骤。     

人体机械功计算方法的实验研究

人体运动中的机械功是评定运动效果的一个重要指标,由于人体生物结构的复杂性和器官功能的多重性特点,目前还没有形成公认的分析计算方法。本研究首先在作者提出的假设之下给出四类人体机械功计算的可能方法。采用Monark864型自行车功率定负荷,JagerEOS型心肺功能测试仪测室生理能耗,用环节分析法计算机械功。14名受试都是职业自行车队队员。本研究结果提示:采用刚体力学模型计算的人体机械功可看作是运动中生理能耗的一次近似,要提高计算准确度,还需考虑其它耗能因素,建立更为精细的人体能量代谢模型。     

Carbohydrate ingestion improves endurance performance during a 1h simulated cycling time trial

This study examined the effect of carbohydrate ingestion on metabolic and performance-related responses during and after a simulated 1h cycling time trial. Eight trained male cyclists (VO 2 peak = 66.5ml kg -1 min -1 ) rode their own bicycles mounted on a windload simulator to imitate real riding conditions. At a self-selected maximal pace, the cyclists performed two 1h rides (separated by 7 days) and were fed either an 8% carbohydrate or placebo solution. The beverages were administered 25 min before (4.5ml kg -1 ) and at the end (4.5ml kg -1 ) of the ride. With carbohydrate feeding, plasma glucose tended (P = 0.21) to rise before the time trial. Compared with rest, the plasma glucose concentration decreased significantly (P < 0.05) at the end of both rides, with no statistically significant difference being observed between treatments. Thereafter, plasma glucose increased significantly (P < 0.05) at 15 and 30 min into recovery, and was significantly higher at 30 min during the carbohydrate trial compared with the placebo trial. No significant changes in plasma free fatty acids were observed during the ride. However, a significant increase (P < 0.05) in free fatty acids was found at 15 and 30 min into recovery, with no difference between trials. Mean power output was significantly (P < 0.05) greater during the carbohydrate compared with the placebo trial (mean - S.E.: 277-3 and 269-3W, respectively). The greater distance covered in the carbohydrate compared with the placebo trial (41.5-1.06 and 41.0–1.06km, respectively; P < 0.05) was equivalent to a 44s improvement. We conclude that pre-exercise carbohydrate ingestion significantly increases endurance performance in trained cyclists during a 1h simulated time trial. Although the mechanism for this enhancement in performance with carbohydrate ingestion cannot be surmised from the present results, it could be related to a higher rate of carbohydrate oxidation, or to favourable effects of carbohydrate ingestion on the central component of fatigue.     

Science and medicine of rowing: A review

The biology and medicine of rowing are briefly reviewed. Effort in a 2000 -m race is about 70% aerobic. Because the boat (and in some instances a cox) must be propelled, successful competitors are very tall, with a large lean mass and aerobic power. Large hearts may lead to erroneous diagnoses of a cardiomyopathy. Large respiratory minute volumes must be developed by chest muscles that are also involved in rowing. The vital capacity is typically large, and breathing becomes entrained. Expiration cannot be slowed relative to inspiration (as normally occurs at high rates of ventilation) and the limiting flow velocity may be reached, with the potential for airway collapse. Performance is strongly related to the power output at the ‘anaerobic threshold’, and lactate measures provide a guide to an appropriate intensity of endurance training. Peak blood lactate levels are higher in males (commonly 11–19 mmol·l -1 and occasionally as high as 25 mmol·l -1) than in females (9–11 mmol·l -1), probably because males have a greater muscle mass in relation to blood volume. The skeletal muscles are predominantly slow twitch in type, developing an unusual force and power at low contraction velocities. Many rowers have a suboptimal diet, eating excessive amounts of fat. Lightweight rowers also have problems of weight cycling. Aerobic power and muscle endurance often change by 10% over the season, but such fluctuations can be largely avoided by a well-designed winter training programme. Injuries include back and knee problems, tenosynovitis of the wrist and, since the introduction of large blades, fractures of the costae.     

我国体育市场管理法规研究

采用调查法和比较法对全国体育市场立法和管理现状进行调查,对部分较早出台并有一定代表性的省市的体育市场管理法规的立法和管理情况进行了研究,提出了体育市场管理立法和管理的原则、基本程序、措施及其一般模式,为规范全国体育市场管理提供参考依据。     

重新认识体育的社会关联

体育与政治之间存在一个悖论，体育的发展与经济实力之间没有直线相关，体育与教育部分重叠，体育与宗教最为近缘，体育可借用科学手段，体育的艺术禀性日益明显，体育与养生反映着两种人生观。     

上海社区体育竞赛参与者的特点探析

本文在专家访谈、问卷调查、数理统计和文献资料分析的基础上,探析了上海社区体育竞赛参与者的特点、参与者对社区体育赛事运作管理的看法等问题。在此基础上从引进社区体育赛事的志愿者、整合社区体育赛事的各种资源、开发社区体育竞赛的无形资产、组建非营利性的专业团队、规范社区体育赛事的服务管理等方面提出了进一步满足上海社区居民日益增长的体育竞赛参赛需求的对策与措施。     

对全面把握游泳训练环节的探讨

从系统观点出发,结合训练实践,对全面把握游泳训练环节进行探讨。认为应强化非智力因素在运动员多年训练中的作用,在育材全过程中不断选材,从整体上把握动态训练的全过程,把培养高水平运动员的整个过程置于一个严格的科学控制之下。     

我国优秀游泳运动员出发技术辅助训练的研究

为改进我国优秀游泳运动员的出发技术,采用观测和实验方法,通过拍摄运动员陆上和水下出发技术录像以及出发计时,对出发技术进行运动生物力学诊断和分析。在此基础上,根据运动员自身特点和不同泳姿提出相应的入水启动方式,并研制出发训练辅助器材,对出发预备姿势、腾起角度以及飞行远度和入水角进行控制。实践证明:这是一种快捷、有效的出发技术辅助训练方法。     

运动性呼吸肌疲劳与耐力性项目的运动能力

影响和限制耐力性运动项目的成绩的生理因素是复杂的和多方面的,取决于训练的强度和运动成绩.大强度持续性运动可导致呼吸肌疲劳.运动性呼吸疲劳可能在决定运动耐量方面起到关键的作用：一方面通过直接影响运动肌力量的生成（外周疲劳）,另一方面,通过肢体用力自感不安反馈引起工作肌运动单位输出功率下降（中枢疲劳）.对呼吸肌进行训练,可能有助于提高耐力性项目的运动成绩.     

Identifying home advantage in international tennis and golf tournaments

A regression analysis of competitors' tournament results in relation to their world rankings was proposed to identify the effect of home advantage in international ‘grand-slam’ tennis and ‘major’ golf tournaments. The results provided little evidence of home advantage in either the grand-slam tennis or the golf tournaments held in 1993. The only possible evidence of home advantage was found in the Wimbledon tennis and the US Open golf championships. Even these findings can be explained, at least partially, by (1) the availability of information concerning the low world rankings of the British tennis players competing at Wimbledon, and (2) selective entry, allowing only the world's top-ranked foreign golfers into the US open golf tournament. In both cases, the lower ranking home competitors have a greater opportunity to perform above their anticipated world rankings. Therefore, provided entry into tennis and golf tournaments is truly ‘open’ to both the host nation's representatives and foreign competitors alike, home advantage does not appear to be a major factor influencing the competitors' performance in such competitions. These findings may be explained by the relatively objective nature of the scoring systems used in tennis and golf, unlike the subjective influence of refereeing decisions on the results of team-games such as soccer.     

青少年业余足球运动员运动倾向性5因素结构模型初探

根据Scanlan等人最新提出的运动倾向性理论模型,结合我国实际情况建立了青少年足球运动员运动倾向性5因素结构模型。运动倾向性被定义为:渴望和决心继续参加足球运动的心理状态。所建立的5因素结构模型认为,运动倾向性是由运动乐趣、参与选择、个人投入、社会约束及参与机会5个因素决定。经确定5个决定因素和运动倾向性的操作定义,编制了相应调查问卷,通过对北京市252名青少年足球运动员实测结果,建立运动倾向性及其影响因素的协方差结构模型,用Lisre 18分析的结果表明:该运动倾向性模型比较符合北京青少年足球运动员。其中运动乐趣、个人投入、参与机会和参与选择4因素对运动倾向性有影响;社会约束对运动倾向性影响不大。