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21.
年级主任负责制是把年级主任作为学校中层干部,相对自主地管理本年级的工作和事务,直接对校长负责。实行年级主任负责制使管理更加科学,更具有针对性、实效性,能激活基层管理并培养一批后备干部。  相似文献   
22.
从国内外的情况看,开发智能化电器已成为当前低压电器行业的重点方向,断路器是低压电器智能化的突破口。  相似文献   
23.
超等长训练适宜于跳跃专项少年运动员专项素质训练,对提高跳跃成绩效果显著,超等长训练对提高肌肉超等长收缩能力的作用显著,高于传统力量训练方法,尤其是跳跃专项少年运动员应积极进行超等长训练。  相似文献   
24.
论述的评估算法模型主要针对常用的各类评估系统,介绍了算法模型的多种形式,这些模型交织在一起,详细地给出了实现算法。算法模型具有很强的实用性,为建立高效和功能强大的计算机评估系统提供参考。  相似文献   
25.
Scale and Translation Invariant Collaborative Filtering Systems   总被引:1,自引:0,他引:1  
Collaborative filtering systems are prediction algorithms over sparse data sets of user preferences. We modify a wide range of state-of-the-art collaborative filtering systems to make them scale and translation invariant and generally improve their accuracy without increasing their computational cost. Using the EachMovie and the Jester data sets, we show that learning-free constant time scale and translation invariant schemes outperforms other learning-free constant time schemes by at least 3% and perform as well as expensive memory-based schemes (within 4%). Over the Jester data set, we show that a scale and translation invariant Eigentaste algorithm outperforms Eigentaste 2.0 by 20%. These results suggest that scale and translation invariance is a desirable property.  相似文献   
26.
ABSTRACT

Introduction: Low energy availability (LEA) results in physiological adaptations, which can contribute to unfavourable health outcomes. Little information exists on risk of LEA in active individuals competing in different sports or levels of competition. The aims of this study were to (1) identify risk of LEA in females competing at different levels of competition and (2) investigate associations between risk of LEA, illness and dietary habits. Methods: The validated questionnaire, ‘Low Energy Availability in Females Questionnaire’ was distributed online (November 2016–February 2017) to assess risk of LEA. Twenty-nine additional questions collected information on demographics, illness history and dietary habits. Participants were considered at risk of LEA if they attained a score of?≥?8 and were grouped into: (i) international; (ii) provincial/inter-county; (iii) competitive; and (iv) recreationally active. Chi-square and logistic regression analyses were used to explore differences between those at risk or not at risk of LEA. Results: Risk of LEA was identified in 40% (n?=?331) of 833 participants and was 1.7 and 1.8 times more likely in international and provincial/inter-county athletes compared to those who were recreationally active (International: odds ratios (OR) 1.68, 95% confidence intervals (95%CI) 1.12–2.54; Provincial/inter-county: OR 1.83, 95%CI 1.20–2.77). In participants at risk of LEA, missing >22 days of training during the previous year due to illness occurred 3 times more frequently (OR 3.01, 95%CI 1.81–5.02). Conclusion: Risk of LEA was widespread in this heterogeneous sample. Awareness of LEA and the development of appropriate energy management strategies to ensure athlete health across levels of competition are required.  相似文献   
27.
The high prevalence of child sexual abuse (CSA) is concerning, particularly as survivors are at increased risk for multiple adverse outcomes, including poor mental health across the lifespan. Children born at an extremely low birth weight (ELBW; <1000 g) and who experience CSA may be a group that is especially vulnerable to psychopathology later in life. However, no research has considered the mental health risks associated with being born at ELBW and experiencing CSA. In this study, we investigated the mental health of 179 ELBW survivors and 145 matched normal birth weight (NBW; >2500 g) participants at ages 22–26 and 29–36. At age 22–26, CSA was associated with increased odds of clinically significant internalizing (OR = 7.32, 95% CI: 2.31–23.23) and externalizing (OR = 4.65, 95% CI: 1.11–19.51) problems among ELBW participants exposed to CSA compared to those who did not, though confidence intervals were wide. At age 29–36, CSA was linked to increased odds of any current (OR = 3.43, 95% CI: 1.08–10.87) and lifetime (OR = 7.09, 95% CI: 2.00–25.03) non-substance use psychiatric disorders, however, this did not hold after adjustment for covariates. Statistically significant differences in mental health outcomes were not observed in NBW participants exposed to CSA compared to NBW participants who were not exposed. Survivors of significant perinatal adversity who are also exposed to CSA may be at higher risk for psychopathology through the fourth decade of life.  相似文献   
28.
大尺寸薄壁钢筋混凝土结构,对温度的变化和基础的不均匀沉降较为敏感。制定合理的施工方案,材料的合理选择、施工流程精心组织保证了裂缝控制效果良好。  相似文献   
29.
由于中国和印度都面对着同样的国际环境,且基本国情相似,特别是在能源安全方面都面临着相同或相似的问题,即近年来经济呈现高速和持续增长,能源问题,尤其是石油问题已成为制约中印经济发展的最大瓶颈,中印都积极面向全球部署本国的能源战略,为迅猛增长的经济谋求充足的能源保障。我国的能源战略应向石油进口渠道多样化及多方面与石油输出国乃至消费国加强合作的途径发展。  相似文献   
30.
通过讨论热力学系统在准静态过程ΔE、A、Q诸量与P-V图中过程曲线之间的关系,可直接从P—V图上判断内能的增减、做功正负及热量交换的方向。  相似文献   
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