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61.
Internationally young people report experiencing sexual abuse and violence within schools. Developments within the field of adolescent sexual harm are increasingly recognising the need for ecological approaches to harm. Yet, to date, interventions with young people displaying harmful sexual behaviours have prioritised individual behaviours and characteristics over place-based interventions.This article presents empirical evidence from a mixed-methods study aimed at understanding the enablers and barriers to preventing and responding to harmful sexual behaviour in schools. Research was carried out in seven schools and four multi-agency partnerships in England, UK. Using evidence from focus groups, observations, case reviews and policy analysis the article outlines nine components that enable, or are barriers to, effective responses and interventions into harmful sexual behaviour in schools. The paper concludes that responses and interventions into harmful sexual behaviour must move beyond responding to individual behaviours to intervening within factors within schools themselves.  相似文献   
62.
将第二个重要极限"limx→∞(1+1/x)x=e"中的1/xx,推广到函数f(x),g(x),从而得到"1∞"型未定式极限的简便算法,给出算例说明该算法的实用性.  相似文献   
63.
以高等数学中极限概念教学为基础,引领学员探究极限概念中丰富的哲学元素、人文素养和实际应用性,融知识、能力、素质于一体,提高学员综合能力.  相似文献   
64.
正态分布是随机变量分布中基础而且核心的分布。中心极限定理支持这样的结果:通过统计的手段,对任一个随机变量的分析和研究,可以借助于正态分布进行。在数理统计的抽样分析中,由(标准)正态分布的统计量的适当组合,产生数理统计中的其他三大基础分布。  相似文献   
65.
中心极限定理在实际中的应用   总被引:1,自引:0,他引:1  
中心极限定理是阐明有些即使原来并不服从正态分布的一些独立的随机变量,它们的总和渐近地服从正态分布.对概率论中的三个重要中心极限定理进行了论述,并总结了它们各自在实际中的应用.  相似文献   
66.
《Sport Management Review》2020,23(3):509-520
Women’s football struggles to build a solid platform in terms of fan interest. However, while an increase in gate receipts can help assist its long-term sustainability, there is limited evidence in the academic literature on the factors influencing spectator demand in women’s football. The authors investigate determinants of stadium attendance for UEFA Women's Champions League (UWCL) matches. Using regression models deployed on 554 UWCL games played between 2009/10 and 2017/18, the authors examine contextual and sport-related variables as the main predictors of stadium attendance. Findings show that there is no continuous growth of attendance over the period examined, and highlight that spectators’ interest is positively associated with five factors: stage of the competition, uncertainty of match outcome, competitive intensity, away club’s reputation and weather conditions. Football governing bodies should put in place initiatives to ensure match outcome uncertainty is maintained as this represents a key determinant to maximise stadium attendance. Based on the specific context of European women’s football, recommendations to foster its development are discussed. These include incentivising investment into the elite women’s game and designing sport policies to encourage participation at grassroots levels.  相似文献   
67.
Research remains unclear on the impact of physiological load on perceptual-cognitive skills in sport. Moreover, no study has examined the training of perceptual-cognitive skills under physiological load. The current study comprised two phases. Firstly, we examined the impact of badminton-specific physiological load on anticipatory skills in expert badminton players (n = 13), including key underlying mechanisms, such as gaze behaviour. Under high physiological load, participants displayed less efficient visual search behaviour and showed a reduction in response accuracy. Secondly, we examined the effects of combining perceptual-cognitive simulation training with the high physiological load. Ten of the expert badminton players were assigned to a combined training group, where the simulation training and the physiological load intervention occurred simultaneously or an independent training group, whereby the two components were completed independently. The combined training group showed a positive change in the efficiency of their visual search behaviours compared to the independent training group, but no significant performance improvements were found. Overall, findings demonstrate that high physiological load is detrimental to experts’ anticipatory skills. However, combining perceptual-cognitive simulation training with high physiological load can potentially negate these debilitating effects.  相似文献   
68.
This cross-sectional study analysed the association of sedentary behaviour (SB) and standing with waist circumference. Finnish adults aged 30-75 years from a sub-sample of population-based Health 2011 Study used a hip-worn tri-axial accelerometer (Hookie AM20, Traxmeet, Ltd, Espoo, Finland) for seven days. Those 1405 participants (57% women) who used accelerometer at least four days, minimum of 10 hours/day, were included. SB and standing were analysed in 6s epochs using validated algorithm. Daily total time, daily number and accumulated time from bouts (30s–5min,30s–10min,30s–15min,30s 30min,>5min,>10min,>15min, >30min) as well as daily number of sit-to-stand transitions were determined. Waist circumference (cm) was measured in standardized way. Participants’ mean age was 52 years (SD 12.2). Mean waist circumference was 97cm (SD 12.3) in men and 87cm (SD 12.7) in women. According to multivariable stepwise linear regression analysis, sit-to-stand transitions [standardised regression coefficient (β)= -0.14, 95%CI -0.20 to -0.09], standing bouts of 30s–5min (β= -0.21, 95%CI -0.26 to -0.15) and number of 30s-30min SB bouts (β=0.12, 95%CI 0.06 to 0.17) were most strongly associated with waist circumference. Besides assessing total SB time, future studies should assess also different bout lengths of SB and sit-to-stand transitions and standing times should be assessed separately.  相似文献   
69.
This study aimed to validate the Sedentary Sphere posture classification method from wrist-worn accelerometers in children. Twenty-seven 9–10-year-old children wore ActiGraph GT9X (AG) and GENEActiv (GA) accelerometers on both wrists, and activPAL on the thigh while completing prescribed activities: five sedentary activities, standing with a phone, walking (criterion for all 7: observation) and 10-min free-living play (criterion: activPAL). In an independent sample, 21 children wore AG and GA accelerometers on the non-dominant wrist and activPAL for two days of free-living. Per cent accuracy, pairwise 95% equivalence tests (±10% equivalence zone) and intra-class correlation coefficients (ICC) analyses were completed. Accuracy was similar, for prescribed activities irrespective of brand (non-dominant wrist: 77–78%; dominant wrist: 79%). Posture estimates were equivalent between wrists within brand (±6%, ICC > 0.81, lower 95% CI ≥ 0.75), between brands worn on the same wrist (±5%, ICC ≥ 0.84, lower 95% CI ≥ 0.80) and between brands worn on opposing wrists (±6%, ICC ≥ 0.78, lower 95% CI ≥ 0.72). Agreement with activPAL during free-living was 77%, but sedentary time was underestimated by 7% (GA) and 10% (AG). The Sedentary Sphere can be used to classify posture from wrist-worn AG and GA accelerometers for group-level estimates in children, but future work is needed to improve the algorithm for better individual-level results.  相似文献   
70.
针对新兴的工程网络计划技术采用逆向思维,在网络计划优化中对于工期优化采用“TFE”法进行优化的新思路,使网络计划工期的优化较为简便.  相似文献   
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