共查询到19条相似文献，搜索用时 343 毫秒
1.
邵桂华 《武汉体育学院学报》2007,41(5):60-65
体育教学是一个复杂的自组织系统,透过混沌论的视角来看,系统内部各组成要素之间的复杂非线性关系是引导其不断自组织演进的关键。非线性关系使简单的体育教学要素耦合成复杂的关联结构,也使偶然性成为建设丰富体育教学场景的积极因素。混沌不仅使我们洞察了预测的局限性,而且指出看似微弱的“蝴蝶力量”也可能经由“相干放大”成为影响体育教学进程的决定性因素。 相似文献
2.
混沌是决定论系统所表现的随机行为的总称。根源在系统内的非线性交叉耦合作用。它是一种回复性非周期运动，是经过整个20世纪才确立下来的一种复杂运动形式，在描述此系统的数学模型中是不包含任何随机因素的完全确定的方程，其研究隶属于非线性动力学，起源于天体力学、气象学、普通力学、电子工程学、生态学等自然科学。洛伦兹的《决定性非周期流》被认为是现代混沌研究的开端。李天岩与约克的《周期三意味着混沌》第一次把混沌当作一个数学名词，并给出了严格的数学定义。1977年在科莫召开了第一次世界混沌会议。混沌成为一门新科学，并产生了自己的语言：分形、分岔、阵发和周期等。 相似文献
3.
大型国际综合性运动会奖牌数预测研究
———以北京奥运会为例 总被引：3，自引：0，他引：3
基于计量经济学理论,依据人口数、人均GDP、主场优势、社会制度、上届奥运会的成绩,利用多元非线性回归分析建立初步模型;考虑世界各国竞技体育实力存在差距,利用模糊C均值聚类分析理论,将竞技体育实力划分为5个等级,通过引入虚拟变量,提出经济学与竞技体育实力差异理论相结合的改进模型,对2008年北京奥运会奖牌数进行预测分析.结果表明,该模型既能揭示世界各国奥运会奖牌数变化的总体趋势,又能克服竞技体育实力差异对预测精度的影响;适用于大型国际综合性运动会奖牌数的预测,具有较强的科学性和可行性. 相似文献
4.
神经网络作为非线性科学的重要学科,近年来发展迅速,在很多领域都得到了广泛的应用。利用人工神经元网络建立运动成绩预测模型对奥运会男子100m第一名成绩进行预测,结果显示预测模型获得的计算值与实际值之间具有较高的拟和精度。因此,建立神经网络预测模型对研究竞技运动训练理论具有重要的实际研究意义。 相似文献
5.
混沌理论视角下的体育教学设计 总被引：3，自引：0，他引：3
混沌理论作为系统科学的基础科学理论,其蝴蝶效应、内在随机性奇异吸引子等相关原理对各个领域产生重要影响。在线性与非线性、封闭与开放性、可控与不可控等方面,对传统体育教学设计与混沌理论指导的体育教学设计进行了比较,得出新时期体育教学设计应重视元认知;应以人为本、关注个体的差异性;应重视学生的创造性思维培养等启示。 相似文献
6.
奥运会奖牌预测国内、外研究动态及发展趋势 总被引：5，自引：2，他引：3
分析了国内、外相关奥运会奖牌预测研究报道,主要对夏季奥运会奖牌预测进行归纳分析.从方法学的角度,将奥运会奖牌预测研究的模型划分为三类,分别对时间序列预测模型、经验模型及智能化预测模型的国内、外研究动态进行了分析.重点分析了目前奥运会奖牌预测研究所运用的计量经济学模型研究方法及成果.在此基础上,进一步分析了目前相关研究优点和存在的不足,并对当前研究动态和发展趋势进行了分析,指出非线性综合模型、基于交叉性影响因素的预测研究和智能化算法是今后一段时期奥运奖牌预测研究发展的趋势. 相似文献
7.
体育统计中回归方程预测精度问题初探 总被引：1，自引：0，他引：1
回归方程的预测精度问题是教学或科研中经常遇到的问题,在回归预测中起着举足轻重的作用。但以前尚无学者专门对该问题进行定量的分析和研究,本文对该问题进行了探索。 相似文献
8.
神经网络作为非线性科学的重要学科近年来发展迅速,在很多领域都得到了广泛的应用。利用人工神经元网络建立运动成绩预测模型,对冬奥会女子速度滑冰500m、1000m、1500m、3000m、5000m第1名成绩进行预测,结果显示预测模型获得的计算值与实际值之间具有较高的拟和精度。因此,建立神经网络预测模型对研究竞技运动训练理论和实践具有重要的实际意义。 相似文献
9.
第29 届北京奥运会田径项目成绩预测情况的比较研究 总被引：2，自引：0，他引：2
运用文献资料和系统分析等方法,对第29届奥运会田径项目成绩预测的有关研究进行对比和分析。研究发现,各种预测方法在对田径运动项目的成绩进行预测时,均存在一定的误差,即使预测精度较高的方法也不能使用于所有奥运会田径项目。通过系统分析建议对田径运动项目成绩的预测,周期性函数应该成为更好的选择;如果采用线性分析则尽量避免点对点预测,区间预测或者发展趋势的预测更有利于合理地部署和安排战略重点项目。 相似文献
10.
对几种奥运成绩预测数模的对比分析及其应用的探讨 总被引：5，自引：0，他引：5
几年来,我国的马其慧、谢亚龙、蒋勇等学者用不同的数学模型方法(简称数模法)对奥运会冠军成绩先后进行过预测,其误差精度均值都有优于国外学者同类预测处,效果是可喜的。但欠不同数模预测效果的对比分析。为此,笔者提出对阵排序的对比方法,对已提出的几种数模的预测效果进行对比分析,得出不同范围内它们的优次关系,优选出最佳数模方法,并对具体应用,提出了新的建议。 相似文献
11.
针对运动成绩变化规律的模糊性、未知性等，运用灰色系统理论的灰色模型方法，建立了男子跳远全国纪录的等维灰数递补GM(1，1)预测模型，并进行后验差检验和关联度分析。结果表明，预测模型精度为一级(GOOD)。同时，运用该预测模型对2002年跳远成绩进行预测。 相似文献
12.
郑旗 《山东体育学院学报》1997,(2)
组合预测是利用各种预测模型所包含的独立有用预测信息来对事物未来发展趋势进行预计、估测的过程。采用灰色系统理论中的关联分析方法,提出以参与组合的单个预测模型与被预测对象的关联系数和关联度为依据,确定组合预测权重的方法。通过单项运动成绩的预测实例,论证了基于灰色关联定权的组合预测方法是比通常单一预测模型更能收到较好预测效果的方法。 相似文献
13.
14.
利用铅球运动员专项成绩与素质训练水平之间的相关关系,借助人工神经网络强大的函数映射能力,提出了铅球运动员专项成绩的神经网络预测模型。该模型克服了多元回归模型和灰色模型需要事先确定数学模型的缺点,更为准确地映射出运动员素质训练指标与专项运动成绩之间的函数关系,从而精确地预测出铅球运动员的专项成绩。并运用Matlab53开发出预测模型的计算机程序,该程序具有语言简单、运行速度快的特点。 相似文献
15.
解决转折期体育事件预测问题的GM（2 ,1）建模方法应用研究 总被引：1，自引：0，他引：1
刘嘉津 《天津体育学院学报》2006,21(3):252-254
从灰色系统建模预测的基本理论出发，跳出传统灰色建模常用的GM（1，1）模型范畴，探索处在转折期体育事件的预测建模新方法，并以不同情况下运用GM（2，1）与GM（1，1）建模效果的实例分析对比，阐明GM（2，1）建模方法是转折期体育事件预测工作的理想方法，从而解决以往包含转折期体育事件难以成功建模预测的难题，为灰色理论在体育领域的推广和应用，打开了更为广泛的发展空间。 相似文献
16.
Cochran AJ 《Journal of sports sciences》2002,20(8):635-641
One-dimensional models of a golf ball are useful in modelling near-normal (90 degrees) impact. The model described here has two masses connected by a non-linear spring in parallel with a non-linear damper. The behaviour of this system in collision with an infinite rigid mass is compared with the results of tests involving real golf balls. Values of the four unknown constants are found by fitting the model results, over a range of impact speeds from zero to 50 m x s(-1), to the coefficient of restitution and duration of contact found in the tests. The simplest model (Model 1) was a good fit for duration of contact over the whole range of impact speeds, but for the coefficient of restitution only at high speed (above 20 m x s(-1)). However, when used with a similar model of a flexible faced club, the simple model predicted the coefficient of restitution of the club-ball combination, determined by direct testing, quite well and as such is a useful screening tool. More complicated Models 2 and 3 fitted the rigid target coefficients of restitution better at low speed than Model 1. However, Models 2 and 3 have other disadvantages and are no better than Model 1 for high-speed impact with flexible faced clubs. 相似文献
17.
Alastair J. Cochran 《Journal of sports sciences》2013,31(8):635-641
One-dimensional models of a golf ball are useful in modelling near-normal (90°) impact. The model described here has two masses connected by a non-linear spring in parallel with a non-linear damper. The behaviour of this system in collision with an infinite rigid mass is compared with the results of tests involving real golf balls. Values of the four unknown constants are found by fitting the model results, over a range of impact speeds from zero to 50 m· s -1 , to the coefficient of restitution and duration of contact found in the tests. The simplest model (Model 1) was a good fit for duration of contact over the whole range of impact speeds, but for the coefficient of restitution only at high speed (above 20 m· s -1 ). However, when used with a similar model of a flexible faced club, the simple model predicted the coefficient of restitution of the club-ball combination, determined by direct testing, quite well and as such is a useful screening tool. More complicated Models 2 and 3 fitted the rigid target coefficients of restitution better at low speed than Model 1. However, Models 2 and 3 have other disadvantages and are no better than Model 1 for high-speed impact with flexible faced clubs. 相似文献
18.
Primary physical education (PPE) is increasingly being recognised for the role it can potentially play in setting a foundation for lifelong engagement in physical activity. However, the majority of the literature continues to focus on the negative features of the subject within the primary context. Whilst acknowledging the existence of these barriers, this paper sets out to take a proactive approach by presenting a conceptual framework for PPE that seeks to support a renewed and positive vision for the future. Based on ideas from complexity thinking, the framework represents a move beyond the more positivist and linear approaches that have long been reported to dominate practices in PPE and recognises learners as active agents engaged in a learning process that is collaborative, non-linear and uncertain. While acknowledging the contested nature of the complexity field, the paper explores how key principles, including self-organisation, emergence, similarity, diversity, connectedness, nestedness, ambiguous bounding, recursive elaboration and edge of chaos, offer a lens that views PPE as a complex system. With the children's learning positioned as the focus of PPE in the educational setting, the paper discusses how complexity principles interweave with the ecological components to help us better understand and more creatively engage with the complex nature of PPE developments. Specifically, these components are identified as PPE learning experiences and their associated pedagogy, teachers and their PPE professional learning and key environmental factors that include the physical environment and key stakeholders who influence developments across the different levels of the education system. The paper concludes by suggesting that this complexity-informed PPE framework represents an open invitation for the all those involved in PPE to engage in a collective process of exploration and negotiation to positively influence developments in PPE. 相似文献
19.
Adam S. Gale-Watts 《European Journal of Sport Science》2016,16(8):948-954
The aim of the present study was to identify whether the relative shape and size characteristics of elite male tennis players have changed over time, and in addition whether any anthropometric parameters characterise the more successful players in Grand Slam tournaments. The height and body mass of the players qualifying for the first round in all four Grand Slam tennis tournaments during the period 1982–2011 was obtained, and successful players defined arbitrarily as those reaching round 3 or beyond. Body mass index (BMI) and the reciprocal ponderal index (RPI) were used as our measures of body shape. Multilevel modelling was used to explore the trend over time using non-linear polynomials. The results suggest that the body shape of elite tennis players has changed over time, with a non-linear (cubic polynomial regression model) increase in BMI and a similar non-linear decline in the RPI. BMI, reflecting greater muscle mass rather than greater adiposity, has emerged as an important factor associated with success, identified by a significantly positive (steeper) “successful player”-by-“year” interaction term. The evidence that the RPI of elite tennis players has also decreased over time, together with a significantly negative “successful player”-by-“year” interaction term, suggests that a more linear (ectomorphic) body shape is a less important factor in terms of success. These results suggest that elite male tennis players are becoming more power trained athletes as opposed to endurance athletes, with greater muscle mass being an important factor associated with success in all Grand Slam tournaments. 相似文献