企业的内涵增长率和可持续增长率     

谷茂春 《甘肃广播电视大学学报》2005,15(4):41-44

介绍了内涵增长率和可持续增长率的含义，通过实例数据对比验证了在内涵增长率、可持续增长率和某种实际增长率情况下销售增长对企业资本结构和长期发展的影响。得出结论企业必须选择适当的发展速度，可持续增长率是企业发展速度的参照。  相似文献   

停止课外训练对小学女生最大心率的影响   总被引：1，自引：0，他引：1  

曹红仙  叶卫兵 《体育科技文献通报》2006,14(2):12-13

以探讨小学生最大心率水平和停止课外训练对小学生最大心率的影响为目的。采取的方法是在跑台上运用Bruce法对停训8周前后的8名小学女生最大心率进行比较,并运用文献资料法,对比国内外学者在停训前后最大心率的研究。结果表明,小学女生停训前后的最大心率、运动能力均无显著差异;用传统的220-年龄推算最大心率可能不准确。  相似文献   

篮球比赛中罚球过程的心理分析及训练     

于佳祥 《哈尔滨体育学院学报》2002,20(3):56-57

对篮球比赛罚球过程中运动员的心理特征进行了简要分析，并提出了临场心理状态的调试方法和训练方法，供同仁研究参考。  相似文献   

赛艇运动员稳态心率的研究   总被引：3，自引：0，他引：3  

刘卫平  杜忠林 《湖北体育科技》2002,21(4):411-413

探讨了赛艇运动员在赛艇测功仪上作中等强度匀速运动时的稳态心率。  相似文献   

远距离单手肩上投篮训练方法探讨   总被引：1，自引：0，他引：1  

李国立 《体育学刊》2005,12(4):113-114

讨论影响投篮命中率有7个因素:手法、瞄准的方向、球的旋转、抛物线、协调性、判断反应和心理因素,并提出提高远距离投篮命中率的训练方法.  相似文献   

篮球运动员拼抢篮板球能力的探讨     

刘森林 《哈尔滨体育学院学报》2006,24(3)

运用理论分析的方法,阐述了篮球运动员抢篮板球能力的重要作用,以及影响篮球内线队员拼抢篮板球能力的四个方面:拼抢意识是抢篮板球能力的首要因素;身体对抗能力是拼抢篮板球能力的重要基础;技术是拼抢篮板球能力的核心;配合是拼抢篮板球能力的保障。  相似文献   

Ecological Study of Graduation Rates and GPA in a Library Credit Course     

Christina Heady  Megan M. Morrison  Joshua Vossler 《The Journal of Academic Librarianship》2018,44(5):642-649

The purpose of this ecological study was to examine the impact of a library credit course on graduation rates and GPA using pre-existing records. Over 20?years of aggregate institutional data were analyzed to evaluate the course's impact on first-time-full-time, white, and black students. Results were mixed: students who took the course were less likely to graduate than their peers who did not take the course but enjoyed slightly higher GPAs at graduation. It was discovered that students taking the course are not representative of the overall student body and struggle academically. Implications for revisions to the library credit course are discussed.  相似文献   

Evening electronic device use and sleep patterns in athletes     

Maddison J. Jones  Brian Dawson  Daniel F. Gucciardi  Peter R. Eastwood  Joanna Miller  Shona L. Halson 《Journal of sports sciences》2019,37(8):864-870

The present study aimed to investigate pre-sleep behaviours (including evening electronic device use) and sleep quantity in well-trained athletes. Seventy well-trained athletes (44 females, 26 males) aged 21 ± 4 y from a range of team and individual sports were asked to complete an online sleep diary for 7 days. The sleep diary included questions about pre-sleep behaviours (e.g. napping, caffeine intake), electronic device use in the 2 h prior to bedtime (e.g. type of device and duration of use) and sleep (e.g. time in bed, sleep onset latency). On average, athletes spent 8:20 ± 1:21 h in bed each night. Associations between age, time in bed and sleepiness suggested that younger athletes spent more time in bed (B = -0.05, p = 0.001) but felt sleepier (r = -0.32, p < 0.01) than older athletes. On average, athletes mostly used electronic devices for 0–30 min prior to sleep. The use of multiple devices in the evening was associated with more perceived difficulty in falling asleep (B = 0.22, p = 0.03), but no associations existed with other sleep variables. In summary, younger athletes may require later start times or improved sleep quality to resolve excessive sleepiness.  相似文献   

废蚕丝中提取丝胶工艺研究     

蓝建京  甘配芳 《河池学院学报》2011,31(5):56-60

通过对透析法、酸析法和冰冻法提取丝胶效果的比较,得出冰冻法是提取丝胶的较好的方法,其最佳的提取条件是:pH=4,-20℃,冰冻时间为13 h,丝胶液浓度为32.8%。  相似文献   

Sand training: Exercise-induced muscle damage and inflammatory responses to matched-intensity exercise     

Henry Brown  Brian Dawson  Martyn J. Binnie  Hugh Pinnington  Marc Sim  Tristan D. Clemons 《European Journal of Sport Science》2017,17(6):741-747

This study compared markers of muscle damage and inflammation elevated by a matched-intensity interval running session on soft sand and grass surfaces. In a counterbalanced, repeated-measures and crossover design, 10 well-trained female athletes completed 2 interval-based running sessions 1 week apart on either a grass or a sand surface. Exercise heart rate (HR) was fixed at 83–88% of HR maximum. Venous blood samples were collected pre-, post- and 24?h post-exercise, and analysed for myoglobin (Mb) and C-reactive protein (CRP). Perceptual ratings of exertion (RPE) and muscle soreness (DOMS) were recorded immediately post- and 24?h post-exercise. A significant time effect showed that Mb increased from pre- to post-exercise on grass (p?=?.008) but not on sand (p?=?.611). Furthermore, there was a greater relative increase in Mb on grass compared with that on sand (p?=?.026). No differences in CRP were reported between surfaces (p?>?.05). The HR, RPE and DOMS scores were not significantly different between conditions (p > .05). These results suggest that in response to a matched-intensity exercise bout, markers of post-exercise muscle damage may be reduced by running on softer ground surfaces. Such training strategy may be used to minimize musculoskeletal strain while still incurring an equivalent cardiovascular training stimulus.  相似文献