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41.
分析高职学生的特点和学习主动性意识缺失的症状,从学生的学习自觉自信、教师的课堂教学反思、学校的学生评价机制等方面,对高职学生学习主动性意识的重塑策略进行探讨,并提出相应的对策。 相似文献
42.
通过鱼骨图的方法对现有智能公交投币机存在识别率偏低的问题进行了分析,提出在智能投币机中采用闭式五角叶轮或增加硬币预处理部分,对现有的智能公交投币机进行改进,使智能公交投币机的硬币辨识率得到提高. 相似文献
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介绍了机械零件刚度模糊可靠性设计变形分布参数和刚度隶属函数的确定,导出了零件刚度模糊可靠度的计算公式,并通过机床主轴模糊可靠性设计实例说明机械零件模糊可靠性的计算方法. 相似文献
47.
数控机床位置伺服在线调试与动态性能分析研究 总被引:2,自引:0,他引:2
介绍一种在数控机床位置伺服系统在线调试中应用系统动态性能分析方法的基本原理,给出了一种位置伺服系统动态响应曲线、动态性能分析及其主要技术指标的实例。 相似文献
48.
Psang Dain Lin Chian Sheng Tzeng 《International Journal of Machine Tools and Manufacture》2007,47(15):2218-2229
Traditionally, twist drills are reconditioned by thinning the web so the correct chisel edge length is restored. Recently, thinning has been included in the original design of drills so as to reduce torque and tool force. Because the International Standards Organization (ISO) has a system which can comprehensively model conventional twist drills but cannot model thinning specifications, this paper presents a system for precise mathematical modeling and CNC control of a 6-axis grinding workstation for drill thinning. The presented method determines the position and orientation of the grinding wheel based on the evaluated rake and clearance angles of ISO standards for 2-flute twist drills. The mathematical model and background are discussed. For verification and demonstration, two experimental drills are produced to the identical ISO standard except that one is thinned. The modeling herein is of value to industry and research if incorporated into computer software for drill design and manufacture. It is suitable for linear notch-type cutting with controlled variable rake angle along the secondary cutting edge for purposes of thinning, notching, dubbing and advanced drill research. 相似文献
49.
Gamification, the application of game elements to non-game settings, continues to grow in popularity as a method to increase student engagement in the classroom. We tested students across two courses, measuring their motivation, social comparison, effort, satisfaction, learner empowerment, and academic performance at four points during a 16-week semester. One course received a gamified curriculum, featuring a leaderboard and badges, whereas the other course received the same curriculum without the gamified elements. Our results found that students in the gamified course showed less motivation, satisfaction, and empowerment over time than those in the non-gamified class. The effect of course type on students' final exam scores was mediated by students' levels of intrinsic motivation, with students in the gamified course showing less motivation and lower final exam scores than the non-gamified class. This suggests that some care should be taken when applying certain gamification mechanics to educational settings. 相似文献
50.
In order to encourage more active learning in the library classroom, the college librarians at the Tidewater Community College/City of Virginia Beach Joint-Use Library turned one of their library instruction classrooms into a dynamic and flexible space using movable seating and iPads. This article explores the reasons for making such a change, the benefits of doing so, how the new classroom has affected librarians' teaching methods, and gives specific information about apps used for class activities. 相似文献