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111.
长篇小说中的古典派典型,原是亨利·菲尔丁所创始的,但对于没有尝试过这种写作手法的人来说,要想坚持这个传统,谈何容易。避免一切过分与夸张,这准则也只是具有最完美写作技巧的艺术大师,并且通过毕生努力,才能获得的一种才能。  相似文献   
112.
教练员在进行多年远景训练规划时,需要有个基本指导思想,即运动员在达到其最佳成绩过程中的各年龄阶段的划分。专家们针对100米和200米运动员确立了以下三个相关的年龄阶段: (1)运动员崭露头角的时期,男19~21岁,女17~19岁;  相似文献   
113.
In 219 recreational male runners, we investigated changes in body mass, total body water, haematocrit, plasma sodium concentration ([Na(+)]), and urine specific gravity as well as fluid intake during a 100-km ultra-marathon. The athletes lost 1.9 kg (s = 1.4) of body mass, equal to 2.5% (s = 1.8) of body mass (P < 0.001), 0.7 kg (s = 1.0) of predicted skeletal muscle mass (P < 0.001), 0.2 kg (s = 1.3) of predicted fat mass (P < 0.05), and 0.9 L (s = 1.6) of predicted total body water (P < 0.001). Haematocrit decreased (P < 0.001), urine specific gravity (P < 0.001), plasma volume (P < 0.05), and plasma [Na(+)] (P < 0.05) all increased. Change in body mass was related to running speed (r = -0.16, P < 0.05), change in plasma volume was associated with change in plasma [Na(+)] (r = -0.28, P < 0.0001), and change in body mass was related to both change in plasma [Na(+)] (r = -0.36) and change in plasma volume (r = 0.31) (P < 0.0001). The athletes consumed 0.65 L (s = 0.27) fluid per hour. Fluid intake was related to both running speed (r = 0.42, P < 0.0001) and change in body mass (r = 0.23, P = 0.0006), but not post-race plasma [Na(+)] or change in plasma [Na(+)] (P > 0.05). In conclusion, faster runners lost more body mass, runners lost more body mass when they drank less fluid, and faster runners drank more fluid than slower runners.  相似文献   
114.
This is the second study of the series, and its aim was to investigate the influence of using the suspended aid on circle kinetics. In addition to the kinematic data recorded for part one (Fujihara & Gervais, 2012), the pommel reaction forces and the force applied from the suspended aid (aid reaction force) were analysed in relation to the motion of a whole-body mass centre. The hip joint moment was also computed by combining all segments in the lower extremities into a single rigid segment. Generally, the use of the aid changed the magnitude of the mass-centre trajectory or horizontal pommel reaction forces but not their patterns. The results also showed that the net hip joint moment was altered during circles with the aid. In summary, a suspended aid can be used as a progression for a variety of goals because it allows gymnasts to practise circles which would not be possible without the aid. When a suspended aid is used, however, practitioners should be aware of the possible kinetic alteration caused by the external force from the aid.  相似文献   
115.
The purpose of this study was to describe the physical activity levels of urban inner city preschoolers while attending Head Start, the federally funded preschool program for children from low-income families. Participants were 158 African American children. Their physical activity during Head Start days was measured using programmed RT-3 accelerometers. Results revealed that the children spent the most time in sedentary and light physical activity, while their participation in moderate-to-vigorous physical activities was low. Given the sedentary class format and limited physical space for the Head Start programs observed, we suggest adding a structured physical activity component to Head Start schools to fight the overweight and obesity crisis.  相似文献   
116.
The aim of this study was to investigate the influence of a suspended aid on the reaction forces during a basic skill on pommel horse. Twenty gymnasts performed three sets of 10 circles with and without a suspended aid on a pommel horse under which two force plates were set. The results confirmed that the suspended aid could reduce the magnitude of the pommel reaction forces during circles while maintaining the general loading pattern. On the left hand, the average and peak forces were attenuated to 0.59 body weight (BW) and 0.85 BW from 0.76 BW and 1.13 BW, respectively. The right hand experienced slightly larger forces with no-aid trials, but the asymmetry between the hands decreased with the aid. Despite a relatively large variability, all gymnasts experienced smaller impact peak forces with the aid. A suspended aid is most commonly used for a beginner gymnast as an introduction to pommel horse exercises. However, this study confirmed that it can also be useful for all levels of gymnasts who would like to practice pommel horse exercises with reduced pommel reaction forces for a purpose such as a progression for learning a new skill, control of training volume, or rehabilitation.  相似文献   
117.
在企业环境中,管理数据流或者实时数据更新是任何数据挖掘操作的一个主要挑战。无论是数据还是元数据.都要确保数据流的稳定、正确、可验。在这种环境下,实时数据更新很复杂,且数据量大而难懂。管理频繁变化的数据和元数据对企业是巨大的挑战。本文阐述了在管理企业数据的任务中的技术问题,并提出了一种解决方法。这种解决方法可以结合多个领域里的知识,如工程技术和统计学,来理解和标准化企业挖掘的准备工作,以使信息采集和质量管理自动化。  相似文献   
118.
准备好应用网络教育的明日教师(上)   总被引:8,自引:0,他引:8  
全球网(www.World Wide Wde)对教育系统的潜在冲击几乎是无限的。然而,如果我们的教师不具备适当的应用网络的知识和技能,实现的冲击会比可能的要小。证据表明,我们的教师需要培训,以便能够有效利用强大的在线资源,培养我们的孩子在数字社会中自我发展的能力。本文的目的在于探讨基于网络的教学对教师教育计划的冲击。  相似文献   
119.
It is a long, tiresome trip between Shanghai and Tübingen, an exhausting flight that is often delayed, followed by hours in a train or car.  相似文献   
120.
In this study, parent-child interaction in two carefully matched subgroups-school-age boys with learning disabilities (LD) who showed a discrepancy between their verbal IQ and performance IQ and had more extensive difficulties in higher-level language abilities (VIQ < PIQ, n = 8) and boys with LD who did not manifest a discrepancy between verbal IQ and performance IQ (VIQ = PIQ, n = 8), were investigated. The effects of the child's language problems on child task performance and on the quality of maternal communication were analyzed in a mother-child problem solving task. Children in the VIQ < PIQ group were found to be less successful on the task than children in the VIQ = PIQ group, and their mothers exhibited lower communication clarity in their instructions than the mothers of the children in the VIQ = PIQ group. An interesting interaction effect was found for communication deviances. For mothers in the VIQ < PIQ group the extent of deficient communication increased from the monologue to the dialogue situation, whereas communication deviances decreased for mothers in the VIQ = PIQ group. Three possible models are discussed in light of the differences between the subgroups.  相似文献   
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