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81.
中国特色社会主义,是中国共产党和全国人民长期艰难探索的结果。作为马克思主义中国化的最新成果,它是新时期的目标航向,是应该毫不动摇坚持的发展道路,是中华民族伟大复兴的行动指南和各族人民团结奋斗的共同思想基础。党的十七届五中全会指出,当前和今后一个时期,世情、国情继续发生深刻变化,我国经济社会呈现新的阶段性特征。只有对中国特色社会主义不断深入认知,并使之引领发展,党和国家的事业才能不断开创新局面。  相似文献   
82.
目前,我国城市配电网中电力电缆的应用愈来愈广泛,系统电容电流越来越大,在发生单相接地时电弧不能熄灭,会造成电弧间歇性的熄灭与重燃,形成弧光接地电压或激发磁谐振危及电气设备绝缘,严重时有可能发展为相间短路,引起事故。为限制单相接地故障电流,6-35KV系统采用中性点通过消弧线圈接地来补偿单相接地时的电容电流使电弧熄灭,限制弧光接地过电压和消除铁磁谐振过电压,现已取得较多的运行经验和较好运行效果。  相似文献   
83.
以河北唐银钢铁有限公司棒材、高线两条轧钢生产线的步进式加热炉实现物料跟踪的全过程为例,论述了步进式加热炉物料跟踪的理念、跟踪的实现过程,重点分析了实现加热炉钢坯物料跟踪的方法和影响跟踪过程准确的几个关键要素:包括装钢定位、步距调整、有钢判断、位置跟踪、炉号跟踪等.提出准确是物料跟踪的核心,实现跟踪准确的前提是控制好炉底...  相似文献   
84.
文中考虑了一类永磁同步电动机的终端滑模控制器设计问题.在控制器设计中利用中继切换控制使系统在给定的当前控制律的作用下运行到某一特定状态(或某一特定区域)后,控制律被切换到有限时间收敛的终端滑模控制器,使得系统在有限时间内达到平衡状态.终端滑模控制器的设计保证了闭环系统所有信号的有界性和平衡点的全局稳定性,以及系统在有限时间内精确地跟踪给定的参考信号.最后,通过一个数值仿真验证了所提算法的正确有效性.  相似文献   
85.
现代化的办学标准是推进教育现代化的重要举措与保障,均衡发展是制定义务教育现代化办学标准的理论基础与核心思想。现代化办学标准的价值取向应当实现:从强调效率向追求均衡及公平的转向、从单项性办学标准向综合性办学标准的转向、从初步均衡向优质均衡的转向、从单一质量观向全面质量观的转向、从政府管学校向政府办学校的转向、从学校的被动发展向主动发展的转向。这种价值观指导下的省级现代化办学标准应当设有硬件建设、师资队伍、经费保障、办学行为、教育质量、文化建设六大领域四十五个现代化的指标体系。  相似文献   
86.
主要是根据风力发电的原理、组成和运行过程,提出风向跟踪风力发电教学实训设备的设计方案,为高职院校风电类实训设备的开发提供参考.  相似文献   
87.
The aim of the reported eye-tracking study was to investigate whether learners integrate information presented on several pages within a digital learning environment and whether the underlying processes differ between a purely text-based and a multi-modal digital learning environment. Participants (N = 97) learned about the development of tornados. Picture presentation (yes vs. no) and presentation of inconsistent information between pages (yes vs. no) was varied between-subjects. Results showed that inconsistent information led to more intense gaze behavior. This indicates that learners re-activated information presented on previous pages to integrate it with the actual information, enabling them to detect the inconsistencies. Furthermore, the data pattern for text-related gaze behavior was not influenced by picture presentation, indicating that cognitive processes in purely text based or multi-modal learning environments are much the same. Comprehension outcomes did not differ between groups. The implications of these results are discussed.  相似文献   
88.
提出一种基于多尺度Gabor滤波特征提取和稀疏表示的SAR图像目标识别方法。首先,在目标分割的基础上,利用Gabor滤波器对SAR目标图像在不同方向上进行滤波,增强目标的局部特征;然后,根据稀疏表示模型,以训练样本特征为原子构建字典,利用稀疏求解算法选择最优的原子集合来表示测试样本特征,进而计算表示系数中非负值的l1范数来判别测试样本。实验结果验证了该算法的有效性与鲁棒性。  相似文献   
89.
The purpose of the present study was to characterise the relationship between relative versus absolute internal and external loads in collegiate basketball players throughout the course of a season. Five Division I basketball players wore triaxial accelerometers throughout the 2015–2016 season and were tensiomyographically assessed weekly. One-way repeated-measure analysis of variance (RM ANOVA) with least-significant-difference (LSD) pairwise comparisons was used to determine which absolute weekly loads were different across the season. Cohen’s d was used to supplement the determination of meaningful relative load changes. Overall RM ANOVA models suggest absolute external load differences occurred (PlayerLoad? = 17.63; IMA? = 31.63). Two-way RM ANOVA models revealed main effect differences were revealed between muscle groups for Tc (F = 9.11) and Dm (F = 3.25). Meaningful relative load changes between weeks were observed for both external and internal. The present study observed that tensiomyography utilised as a tool to monitor internal load may be more suitable for detecting fatigue from relative external load changes versus absolute load attained. Limiting weekly training volume changes to ≤10% may maintain appropriate adaptation. Mediolateral plane IMA? and adductor longus muscle group may be pertinent metrics when monitoring female collegiate basketball athletes.  相似文献   
90.
The purpose of the study was to investigate the effect of different kicking modality, i.e., erratic-dynamic target (EDT) versus static target (ST) on the performance of the roundhouse kick in two groups of taekwondo athletes of different skill level. Three-dimensional analysis and surface electromyography (SEMG) analysis were performed on 12 (Group A: six sub-elite, Group B: six elite) athletes to investigate muscle co-activation pattern under two conditions, i.e., EDT versus ST. In the results, the muscle recruitment ratio of the agonistic muscles was higher for Group A, whereas Group B had higher recruitment ratio for antagonist muscles. Overall, the co-activation index (CI) of hip joints appeared higher in the extensors for Group A, whereas higher CI was observed in flexor muscles for Group B with comparatively higher CI during EDT condition than ST condition. Higher value of CI was observed in flexor muscles of the knee joints among Group A during EDT conditions, in contrast, higher CI in the extensor muscles was observed among Group B during ST conditions. In conclusion, the study confirmed that erratic-dynamic movements of target could change the movement coordination pattern to maintain the joint stability of participants.  相似文献   
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