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针对发动机测控系统的恒转速测试,用LabVIEW的PID控制器设计了发动机恒转速控制系统。系统通过调节数采卡的模拟电压输出调节励磁电流的方式对测功系统负载进行控制,调节数采卡的脉冲输出和控制数字I/O的方式控制步进电机的运转从而实现对油门位置的控制,采用数字PID控制器。通过试验验证了系统的可行性。 相似文献
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本设计采用两个独立的VCO振荡器和宽带放大器获得不同波段正弦信号,波段内频率调节方便,平坦度好,系统不需设置AGC放大器,设计调试方便.该方案主要由压控LC振荡器、锁相环、宽带放大器、缓冲器、高频丙类功率放大器、前置分频器、高频检波器、V/F变换器及单片机最小系统组成.为提高频率稳定度,压控LC振荡器中引入了锁相技术.为提高输出电压的测量精度和减少占用单片机口线,峰值检波器中采用了抑制温度漂移偏置方式,A/D变换采用V/F变换测频方式.为提高高频功率放大器的效率,放大器采用丙类工作方式.为保证系统关机后再次开机时输出参数保持不变,系统设置了输出参数记忆电路.为使显示内容丰富、清晰直观,显示部分采用了液晶显示.为提高电压测量精度,系统采用了软件拟合技术.整个系统在单片机的控制下协调工作. 相似文献
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本文针对兆瓦级的永磁直驱同步风电机组(D-PMSG)多运行于并网发电状态,在DIgSILENT/PowerFactory仿真软件中搭建了基于双PWM全功率变流器的D-PMSG并网仿真模型;阐述了系统的运行原理,对机侧和网侧的变流器的控制策略进行了详细的分析,该系统能够实现风能最大功率追踪以及并网控制,仿真结果验证了所建模型的正确性和控制策略的可行性. 相似文献
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详细介绍了电压调节器的分类、功能,对发动机未工作和工作时发电机输出电压的几种状态下,电压调节器调压电路的工作原理、电流路径都进行了细致的分析,对电路中各端子的名称和作用也作了说明.当电源系统中出现故障时,电压调节器能及时警示驾驶员,对调节器常见故障的原因也作了较详细的阐述. 相似文献
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为了克服单纯用Simulink元件库建立光伏阵列模型过程复杂的缺点,利用光伏阵列输出特性方程和MATLAB/Simulink建立了基于M函数的光伏阵列最大功率控制的通用仿真模型.将该通用模型用于单相光伏并网系统MPPT中,并在不同光照强度下,对单相并网系统进行仿真实验,仿真结果表明:该模型能快速找到新的工作点,并保持稳定,具有良好的动态特性和强鲁棒性. 相似文献
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为生活的体育还是为体育的生活--现代体育教育目的辨析 总被引：1，自引：0，他引：1
体育教育与学生的生活之间的关系正被颠倒,不是体育教育适应学生生活而是学生生活适应体育教育.学生原本渴望丰富多彩的体育活动,体育运动也原本为繁荣的学生生活自然展开,学生则可以自由自在的在运动场上"玩耍"、"游戏",充分吸收体育运动的营养助长其生活能力,张扬起生命能力并创造美妙的生活.然而现实生活中的体育教育则肆无忌惮地控制了学生本该属于他们的生活,出现了"学生爱打球、喜欢玩耍,却不喜欢体育课"的奇怪现象,这使得他们不自然、不自由和不自主,同时,也产生了对体育课的逆反,甚至厌恶的抵触情绪.因此,体育教育者应当深刻反省自我,为了学生今天和明天的幸福生活. 相似文献
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Rodgers WM Wilson PM Hall CR Fraser SN Murray TC 《Research quarterly for exercise and sport》2008,79(2):222-234
This series of three studies considers the multidimensionality of exercise self-efficacy by examining the psychometric characteristics of an instrument designed to assess three behavioral subdomains: task, scheduling, and coping. In Study 1, exploratory factor analysis revealed the expected factor structure in a sample of 395 students. Confirmatory factor analysis (CFA) confirmed these results in a second sample of 282 students. In Study 2, the generalizability of the factor structure was confirmed with CFA in a randomly selected sample of 470 community adults, and discriminant validity was supported by theoretically consistent distinctions among exercisers and nonexercisers. In Study 3, change in self-efficacy in conjunction with adoption of novel exercise was examined in a sample of 58 women over 12 weeks. Observed changes in the three self-efficacy domains appeared to be relatively independent. Together, the three studies support a multidimensional conceptualization of exercise self-efficacy that can be assessed and appears to be sensitive to change in exercise behavior. 相似文献
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关于全民健身服务业的调研报告 总被引：4，自引：0，他引：4
全国政协教科文卫体委员会有关委员就全民健身服务业在我国的发展状况,先后赴天津、北京、浙江3省市进行了专题调研。揭示了全民健身服务业的内涵及其基本特征,分析了全民健身服务业在我国发展的基本现状,指出发展全民健身服务业的重要意义与作用,进而提出当前我国全民健身服务业发展中存在的主要问题及对策。 相似文献
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俄罗斯青少年体育发展的战略目标是:创造条件使青少年能够利用先进的体育场地设施进行系统的体育锻炼,养成健康的生活方式。为实现这一战略目标,俄罗斯政府大力加强各种体育场馆与体育设施建设,为青少年体育锻炼提供场地设施保障;推行新的国家体育教育标准,提高体育教学质量;设立各种体育活动计划,完善各类学生体育竞赛活动体系;广泛宣传体育是健康生活方式最重要组成部分的理念。俄罗斯青少年体育发展战略对于我国青少年体育发展的启示是:俄罗斯宣传体育与健康生活方式的举措对于解决我国青少年体育所面临的"重智育,轻体育"问题是一个很好的启示;与俄罗斯新的国家体育教育标准相比较,应该提高我国青少年体育活动的标准;俄罗斯对体育基础设施建设的重视及所采取的措施值得我国学习借鉴。 相似文献
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Andrew T. Harveson James C. Hannon Timothy A. Brusseau Leslie Podlog Charilaos Papadopoulos Lynne H. Durrant 《Research quarterly for exercise and sport》2013,84(2):214-216
Purpose: The purpose of this study was to determine differences in cognition between acute bouts of resistance exercise, aerobic exercise, and a nonexercise control in an untrained youth sample. Method: Ninety-four participants performed 30 min of aerobic exercise, resistance exercise, or nonexercise separated by 7 days each in a randomized crossover design. After each exercise intervention, participants were assessed using 2 cognitive tests. The Dot, Word, and Color elements of the Stroop Test (Victoria version) and Parts A and B of the Trail-Making Test were used to measure cognition. Results: Acute resistance and aerobic exercise resulted in similar improvements over nonexercise in all forms of the Stroop Test. Acute aerobic exercise led to improved performance over nonexercise and resistance exercise in Part B of the Trail-Making Test. Neither exercise intervention showed significant changes in time to complete Part A of the Trail-Making Test. Boys outperformed girls on the Stroop Dot and Color Test following acute aerobic exercise, in the Stroop Dot, Word, and Color Test following acute resistance exercise, and in the Stroop Color Test and Trail-Making Test Part B following nonexercise. Conclusions: Both acute resistance and aerobic exercise increased measures of cognition over a nonexercise control in untrained high school youth. These findings suggest the merits of acute resistance exercise as an alternative or complement to aerobic activity for educators aiming to increase youth physical activity and cognitive function concurrently. 相似文献
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Anne E. Cox Sarah Ullrich-French Brian F. French 《Measurement in physical education and exercise science》2016,20(1):38-49
Being attentive to and aware of one’s experiences in the present moment with qualities of acceptance and openness reflects the state of mindfulness. Positive associations exist between state mindfulness and state autonomous motivation for everyday activities. Though this suggests that state mindfulness links with adaptive motivational experiences, no suitable measure of state mindfulness exists that would facilitate the examination of these relationships in a physical activity context. Thus, we revised the State Mindfulness Scale (Tanay & Bernstein, 2013) and provided score validity evidence for the measure in a physical activity context. A bi-factor model reflecting mindfulness of the mind and body as specific factors and a general mindfulness factor was supported. Validity evidence, such as positive relationships with intrinsic motivation, and a negative relationship with body surveillance support score use. The revised scale can facilitate investigations of the role of mindfulness in physical activity settings. 相似文献
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对体育教育专业学生素质教育的研究 总被引：1，自引：1，他引：0
付志华 《体育成人教育学刊》2003,19(1):47-48
素质教育的实施对体育专业学生素质的全面发展提出了新的要求。构建切实可行的学生素质培养方案，应从思想品德、知识、能力方面入手，根据各年级学生在上述各方面的差异，具体方案的制定应体现出递进性、差异性与可操作性。 相似文献
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