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101.
大学生助学贷款的博弈分析   总被引:2,自引:0,他引:2  
助学贷款本是一项利国利民的政策,但这项政策却遭受了空前的信用危机。文章通过对学生和银行的行为进行博弈分析,认为纯粹靠道德等内在诚信来约束学生的还贷是无用的,必须建立起一套完整的外在诚信约束机制。文章还设计了助学贷款的“三维”被迫诚信机制,以明确助学贷款中政府、银行、贫困生家庭和借款学生的权责和义务。  相似文献   
102.
幼儿园游戏活动形式各异,既相对独立又相互联系,体现出自由游戏自由度高、区域游戏选择性大、主题游戏综合性强;活动结构具有由低到高发展、活动层次具有逐级递进、活动内容具有交叉互补的鲜明特征;在此基础上,有目的、有意识地整合各种游戏活动,形成游戏形式自然地贯穿于幼儿一日活动的基本结构,实现游戏促进幼儿发展的整体功效。  相似文献   
103.
This study investigated the evolution of physical and technical performances in the English Premier League (EPL), with special reference to league ranking. Match performance observations (= 14,700) were collected using a multiple-camera computerised tracking system across seven consecutive EPL seasons (2006–07 to 2012–13). Final league rankings were classified into Tiers: (A) 1st–4th ranking (= 2519), (B) 5th–8th ranking (= 2965), (C) 9th–14th ranking (= 4448) and (D) 15th–20th ranking (= 4768). Teams in Tier B demonstrated moderate increases in high-intensity running distance while in ball possession from the 2006–07 to 2012–13 season (< 0.001; effect size [ES]: 0.68), with Tiers A, C and D producing less pronounced increases across the same period (< 0.005; ES: 0.26, 0.41 and 0.33, respectively). Large increases in sprint distance were observed from the 2006–07 to 2012–13 season for Tier B (< 0.001; ES: 1.21), while only moderate increases were evident for Tiers A, C and D (< 0.001; ES: 0.75, 0.97 and 0.84, respectively). Tier B demonstrated large increases in the number of passes performed and received in 2012–13 compared to 2006–07 (< 0.001; ES: 1.32–1.53) with small-to-moderate increases in Tier A (< 0.001; ES: 0.30–0.38), Tier C (< 0.001; ES: 0.46–0.54) and Tier D (< 0.001; ES: 0.69–0.87). The demarcation line between 4th (bottom of Tier A) and 5th ranking (top of Tier B) in the 2006–07 season was 8 points, but this decreased to just a single point in the 2012–13 season. The data demonstrate that physical and technical performances have evolved more in Tier B than any other Tier in the EPL and could indicate a narrowing of the performance gap between the top two Tiers.  相似文献   
104.
ABSTRACT

The objective of this study was to create a valid, self-reported, game-specific soccer competence scale. A structural model of perceived competence, performance measures and motivation was tested as the basis for the scale. A total of 1321 soccer players (261 females, 1060 males) ranging from 12 to 15 years (13.4 ± 1.0 years) participated in the study. They completed the Perceived Game-Specific Soccer Competence Scale (PGSSCS), self-assessments of tactical skills and motivation, as well as technical and speed and agility tests. Results of factor analyses, tests of internal consistency and correlations between PGSSCS subscales, performance measures and motivation supported the reliability and validity of the PGSSCS. The scale can be considered a suitable instrument to assess perceived game-specific competence among young soccer players.  相似文献   
105.
The aim of this study was to identify the dynamics of tactical behaviour emerging on different timescales in football small-sided games and to quantify short- and long-term exploratory behaviour according to the number of opponents. Two teams of four professional male footballers played small-sided games against two different teams with a variable number of opponents (3, 5 and 7). Data were collected using a combination of systematic observation and a non-differential global positioning system (15 Hz). The temporal diversity and structural flexibility of the players were determined by calculating the dynamic overlap order parameter q, entropy and trapping strength. Analysis of the exploratory dynamics revealed two different timescales, forming a different metastable landscape of action for each constraint. Fast dynamics lasted on average a few seconds and consisted of changes in tactical patterns. The long timescale corresponded to the shared tasks of offence and defence lasting tens of seconds. The players’ tactical diversity decreased with an increasing number of opponents, especially in defence. Manipulating numerical imbalance is likely to promote changes in the diversity, unpredictability and flexibility of tactical solutions. The fact that the temporally nested structure of constraints shaped the emergence of tactical behaviour provides a new rationale for practice task design. The manipulation of numerical imbalance on the timescale of a few tens of seconds, on which the exploratory behaviour of players saturates, may help coaches to optimise the exploratory efficiency of the small-sided games.  相似文献   
106.
Dribbling speed in soccer is considered critical to the outcome of the game and can assist in the talent identification process. However, little is known about the biomechanics of this skill. By means of a motion capture system, we aimed to quantitatively investigate the determinants of effective dribbling skill in a group of 10 Under-13 sub-elite players, divided by the median-split technique according to their dribbling test time (faster and slower groups). Foot-ball contacts cadence, centre of mass (CoM), ranges of motion (RoM), velocity and acceleration, as well as stride length, cadence and variability were computed. Hip and knee joint RoMs were also considered. Faster players, as compared to slower players, showed a 30% higher foot-ball cadence (3.0 ± 0.1 vs. 2.3 ± 0.2 contacts · s?1, < 0.01); reduced CoM mediolateral (0.91 ± 0.05 vs. 1.14 ± 0.16 m, < 0.05) and vertical (0.19 ± 0.01 vs. 0.25 ± 0.03 m, < 0.05) RoMs; higher right stride cadence (+20%, < 0.05) with lower variability (< 0.05); reduced hip and knee flexion RoMs (< 0.05). In conclusion, faster players are able to run with the ball through a shorter path in a more economical way. To effectively develop dribbling skill, coaches are encouraged to design specific practices where high stride frequency and narrow run trajectories are required.  相似文献   
107.
Abstract

This paper explores multiple and complex relationships between football (soccer), politics, and the economy in postcolonial Zambia. Based on archival and oral sources collected in Zambia, the paper argues that President Frederick Chiluba’s government failed to support football development when it came into power in 1991 because it was elected on a platform of liberalizing the collapsing national economy. Chiluba privatized state-owned companies that were sponsoring the game resulting in the plummeting of the local standards and migration of talented footballers abroad in search of better livelihoods. Furthermore, the paper argues that while the exodus of talented footballers led to the deterioration of the standards of the local league, their transnational experience boosted the performance of the Zambia national football team. This led to the emergence of one of the best national teams the country has ever had. Unfortunately, this particular team perished in the Gabon air disaster in 1993 following the government’s disinvestment in the game. However, a few months after the disaster, the country managed to rebuild a national football team, which emerged as runners up to Nigeria in the 1994 African Cup of Nations final as a result of a large pool of local and foreign-based football players.  相似文献   
108.
杨红  殷姿 《体育科研》2016,(1):85-87,92
本文主要采用历史文献法,以明宫词为主,明史及明代野史杂记为辅,考辨明代天启年间,后宫不同地位的宫女平日里的休闲活动。宫女游戏是女性体育的组成部分,笔者在大量文献中发现了些许新材料,以期填补女性体育史中的空白。  相似文献   
109.
运用文献资料、问卷调查、专家访谈、数理统计及回归统计等方法,以上海市部分少体校青少年足球培养为研究对象,以人力资本理论为指导进行研究并发现:1)少体校足球后备人才培养轻视素质培养,模式陈旧单一,培养观念需转变;2)应及时解决以人力资本理论为指导研究对象存在的一些可能被忽视的问题;3)以人力资本理论为指导,加强研究对象与其他培养体系交流,尝试建立合理的交流渠道和富有市场机制的转会费机制,保障青少年足球人才的人力资本能够在培养过程中甚至进入职业队后得到充分发挥。  相似文献   
110.
体感游戏作为体育运动与电子科技的结合产品,对其在青少年体力活动干预方面的研究有重要意义。研究从体力活动的促进、能量消耗、运动康复、社会价值以及心理效应等方面对体感游戏进行分析,发现体感游戏对青少年体力活动有明显促进作用,能满足其锻炼的需求,且对青少年心理健康具有积极地影响,能作为青少年体力活动干预的有效手段之一。  相似文献   
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