高频脉冲电源参数对 Fe-ZrO2复合电沉积镀层纳米含量的影响

为改善低温镀铁工艺镀层的耐磨损耐腐蚀性能,提高镀层表面硬度,以GKDM系列高频脉冲电镀电源为实验复合电沉积工艺电源并配合超声．机械搅拌制备纳米Fe-ZrO2镀层。研究了高频脉冲电源参数：峰值电流导通（TON）、关闭（TOFF）时间;一组正脉冲（TF）负脉冲（TR）的工作时间对镀层表面纳米含量的影响。结果表明当GKDM系列高频脉冲电源TON=20×0．1ms,TOFF=80×0．1ms时,纳米沉积分布均匀致密,质量分数高。     

基于广义比例积分和重复控制的APF控制策略

采用广义比例积分控制和快速重复控制算法串联的方式,应用在APF控制系统中．通过对系统幅频特性分析表明,串联的控制系统提高了APF系统开环传递函数的相角裕度,提高了系统在高频段的动态稳定性能．通过仿真分析,可以快速实现无静差跟踪控制．     

幂级数展开的一种新途径

复变函数的幂级数展开有多种方法,如变量代换法,分项分解法,幂级数乘法,待定系数法,逐项求积法,解微分方程法.将推广的高等代数理论融入复变函数是复变函数展成幂级数的一种新方法.     

建筑结构地震响应混沌特性及影响因素分析

采用混沌时间序列分析方法分别对以经典混沌信号和地震动为激励的结构响应进行混沌特性分析,从关联维数、Kolmogorov熵及最大Lyapunov指数等定量指标的角度,考察结构自振周期、地震动的类型和幅值等因素对结构地震响应的非线性特性的影响。研究结果表明:在经典混沌信号和地震动作用下,经过结构的放大和滤波作用,结构加速度响应仍然保留了混沌特性,且通过混沌参数的变化程度能够判断结构是否进入弹塑性状态。结构自振周期为结构加速度响应的混沌特性的主要影响因素;幅值对经典混沌信号作用结构下加速度响应的混沌特性影响较为显著;而地震动的类型、幅值等因素对地震动作用下响应的混沌特性影响更为显著。     

Dissecting through Barriers: A Follow-up Study on the Long-Term Effects of Interprofessional Education in a Dissection Course with Healthcare Professional Students

Several studies have shown significant improvements in the attitudes and perceptions of healthcare professional students toward interprofessional education (IPE) immediately following intervention with IPE courses. However, there remains little evidence on the lasting effects of IPE courses and the long-term influences of these IPE experiences are poorly documented. The purpose of this study is to assess the long-term effects of an intensive, ten-week interprofessional gross anatomy dissection course at McMaster University. Attitudes and perceptions of past participants towards interprofessional learning were evaluated, now that they have started working with other healthcare professionals outside of the IPE course setting. Thirty-four past participants who have clinical experience working in interprofessional settings or are currently working in the healthcare field completed a follow-up questionnaire consisting of a modified Readiness for Interprofessional Learning Scale (RIPLS) and open-ended questions. Quantitative analysis revealed a significant decrease in their attitude towards teamwork and collaboration and respect for other health professions, but a significant improvement in their understanding of roles and responsibilities compared to their results immediately after the IPE intervention. Qualitative analysis of open-ended questions revealed several themes such as developing interprofessional competencies, developing relationships, and remembering the strengths of the IPE dissection course. The results of this study indicate that the IPE experience in anatomy was highly valued by the students and that past participants maintain a clear understanding of their scope of practice, but the reality of clinical practice may have eroded gains made in the program. Anat Sci Educ. © 2018 American Association of Anatomists.     

《红楼梦》梦描写审美刍议

通过对《红楼梦》系列梦的分析,揭示了梦在结构全篇、映村现实、寓言象征、心理仿真等方面所起的作用,肯定了梦描写的审美价值。     

等比级数在级数中的应用

文章阐述了等比级数∞n=0axn=a1-x(|x|<1)在求幂级数的和函数以及将函数展开成幂级数中的重要作用。     

数列在力学中的应用

为研究各物理量之间的定量关系，常常要用到许多数学知识。中学物理教学中应有意识地引导学生运用数学知识解决物理问题，培养学生这方面的能力。将数列用于解决相关的物理问题有助于培养学生的这一综合能力。     

关于幂级数的收敛半径的计算公式

给出了幂级数收敛半径的计算公式，它是通常计算公式的推广。     

一个数学历史名题的模型建立及其教学设想--谈"兔子繁殖问题"

在中学数学建模教学中，一要选择好合适的问题，这是数学建模课取得良好教学效果的基础，兔子繁殖同题就是一个很典型的数学建模案例，建立它的数学模型，可以从诸如用图式直接计数、建立递推关系式、矩阵表达式和组合表达式等多个角度入手；二要采取有效的教学方法，这是取得良好课堂教学效果的关键，其中，在教学中遵循“数学化”原则，以及问题解决的历史发展顺序，将有助于学生进行有效的学习。