电动车能量再生技术     

陈家新  江建中  汪信尧 《上海大学学报(英文版)》2003,7(2):173-177

1　Introduction　Therateddistanceisoneofkeyfactorstolimitthedevelopmentofelectricvehicle (EV)sinceEVwasin vented .Itisawayforincreasingtherateddistancetoputtheadvancedenergyregenerationtechnologyintouse .Manyexperimentsprovethattheactualrateddistanceofaelectricscooterunderthecityroadsur roundingsisabout 35 - 45kmwhileitisabout 5 5 - 6 5kmunderthestandard proving ground .Moreover ,JapanToyotaalsoprovedthattherateddistancecouldbeincreasedby 2 0 %whenusingtheenergyregenera tionsysteminEV .Soi…  相似文献   

浅谈主次梁交叉部位负筋的合理排放     

修昱  夏克 《鸡西大学学报》2003,3(4):71-71,75

本文结合计算分析，得出在主次梁交叉部位负筋的合理排放位置为次梁负筋放在主梁负筋上面。  相似文献   

从马斯洛高峰体验理论探讨儿童游戏     

李东林 《四川教育学院学报》2007,23(B10):3-4,7

本文将马斯洛高峰体验理论与儿童游戏体验相联系，从体验的角度探讨儿童游戏，从自我实现获得高峰体验这个途径对指导儿童游戏提出建议。  相似文献   

西域美丽风情的热情赞歌——论宋伯鲁西域诗的爱国情怀     

刘靖远 《新疆教育学院学报》2007,23(1):1-4

清末诗人宋伯鲁的西域诗有自己独有的特点。他的西域诗维护民族团结和祖国统一,在诗中主张安民富民,尽情描绘祖国西陲河山的壮丽,物产的丰富,把这里的花花草草都写活了;他的《胡桐行》是描写胡杨的绝唱。  相似文献   

起重机力矩限制器单片机控制系统分析     

许德良  马忠海 《中国教育技术装备》2011,(30)

介绍起重机力矩限制器的工作原理,利用AT89C52单片机设计起重机力矩限制器控制系统。  相似文献   

Effect of gear ratio on peak power and time to peak power in BMX cyclists     

Lee P. Rylands  Simon J. Roberts  Howard T. Hurst 《European Journal of Sport Science》2017,17(2):127-131

The aim of this study was to ascertain if gear ratio selection would have an effect on peak power and time to peak power production in elite Bicycle Motocross (BMX) cyclists. Eight male elite BMX riders volunteered for the study. Each rider performed three, 10-s maximal sprints on an Olympic standard indoor BMX track. The riders’ bicycles were fitted with a portable SRM power meter. Each rider performed the three sprints using gear ratios of 41/16, 43/16 and 45/16 tooth. The results from the 41/16 and 45/16 gear ratios were compared to the current standard 43/16 gear ratio. Statistically, significant differences were found between the gear ratios for peak power (F(2,14)?=?6.448; p?=?.010) and peak torque (F(2,14)?=?4.777; p?=?.026), but no significant difference was found for time to peak power (F(2,14)?=?0.200; p?=?.821). When comparing gear ratios, the results showed a 45/16 gear ratio elicited the highest peak power,1658?±?221?W, compared to 1436?±?129?W and 1380?±?56?W, for the 43/16 and 41/16 ratios, respectively. The time to peak power showed a 41/16 tooth gear ratio attained peak power in ?0.01?s and a 45/16 in 0.22?s compared to the 43/16. The findings of this study suggest that gear ratio choice has a significant effect on peak power production, though time to peak power output is not significantly affected. Therefore, selecting a higher gear ratio results in riders attaining higher power outputs without reducing their start time.  相似文献   

Impact absorption of tennis shoe-surface combinations     

S.?J.?DixonEmail author  V.?H.?Stiles 《Sports Engineering》2003,6(1):1-9

The aim of this study was to investigate, for typical shoes and surfaces used in tennis, the relative role of the shoe and surface in providing cushioning during running. Five test surfaces ranging from concrete to artificial turf were selected, together with two shoe models. Impact absorbing ability was assessed mechanically using drop test procedures and biomechanically using peak magnitude and rate of loading of impact force and peak in-shoe pressure data at the lateral heel. Differences in biomechanical variables between shoe-surface combinations were identified using a two-way ANOVA (p < 0.05). Mechanical test results were found to rank the surfaces in the same order regardless of the shoe model, suggesting that the surface is influential in providing cushioning. However, for all mechanical and biomechanical (p < 0.05) variables representing impact absorbing ability, it was found that the difference between shoes was markedly greater than the differences between surfaces. The peak heel pressure data were found to rank the surfaces in the same order as the mechanical tests, while impact force data were not as sensitive to the changes in surface. Correlations between mechanical and biomechanical impact absorption highlighted the importance of testing the shoe-surface combination in mechanical tests, rather than the surface alone. In conclusion, mechanical testing of the shoe-surface combination was found to provide a strong predictor of the impact absorbing ability during running if pressure data were used. In addition, for typical shoe-surface combinations in tennis, the shoe was found to have more potential than the surface to influence impact loading during running. Finally, in-shoe pressure data were found to be more sensitive than force plate data to changes in material cushioning.  相似文献   

日粮不同蛋氨酸水平对山鸡产蛋高峰期生产性能的影响   总被引：1，自引：0，他引：1  

GUO Hong-qi 《铜仁职业技术学院学报》2007,(3)

试验选取46～48周龄,健康无病、体型、体重基本一致的产蛋高峰期山鸡200只,随机均分为5组,1个对照组(Ⅴ组),4个试验组(Ⅰ、Ⅱ、Ⅲ、Ⅳ组),对照组蛋氨酸水平为0.22%,每组设10个重复,每个重复4只山鸡。每组基础日粮相同,蛋氨酸水平为0.22%,各组蛋氨酸添加量分别为0、0.05%、0.10%、0.15%、0.20%(每组添加量递增0.05%),试验期2个月。结果表明,日粮中添加适宜蛋氨酸水平不仅维持较长时间的产蛋高峰期和理想的产蛋峰值,显著地提高产蛋量和蛋重,而且还能提高饲料报酬和经济效益。试验结果表明:山鸡产蛋高峰期日粮蛋氨酸水平为0.37%。  相似文献   

解析滑轮的转动     

蔡厚贵 《贵阳学院学报(自然科学版)》2011,6(3):13-17

在滑轮问题中,绳的张力并没有直接作用在滑轮上。分析定滑轮和动滑轮的转动,发现绳的张力是通过转化为摩擦力矩或支承力矩间接起作用的。并且在滑轮的转动中。摩擦力矩总是在发挥着作用。  相似文献   

飞秒涡旋光与产生的3次谐波在空气中的耦合传输     

展林弟  钟志萍  徐立桐  奚婷婷  郝作强 《中国科学院大学学报》2021,38(4):450-458

模拟飞秒涡旋光在空气中成丝产生涡旋3次谐波的过程。研究初始基频波的扰动分布和峰值功率对双色涡旋光演化的影响。对于具有对称扰动分布的初始基频波,双色涡旋不受初始峰值功率影响,能够在成丝过程中保持环形强度分布。但是,在高峰值功率情况下,涡旋的螺旋相位分布受到多丝的影响,多丝引起的相位积累效应破坏了双色涡旋的螺旋相位分布。对于具有不对称扰动的初始基频波,当形成多细丝时,双色涡旋的空间环形分布和螺旋相位分布都会被破坏。  相似文献