基于水平集方法的连续体结构拓扑优化方法研究     

范文锋  何景武 《安阳工学院学报》2007,(1):109-112

采用水平集方法描述结构的拓扑及其变化,使用紧支径向基函数对计算区域的水平集进行插值以得到参数化的水平集方法。针对给定体积约束下结构最小柔度的拓扑优化问题,推导了目标函数对插值系数的灵敏度及拓扑优化的迭代格式,数值计算表明,使用该方法进行结构拓扑优化得到的结果边界形状光滑连续且计算稳定性较好。  相似文献   

理工类院校英语专业课程设置优化研究     

张建平  李欢 《江西教育学院学报》2011,32(4):94-97

通过对英语专业学生进行问卷调查、访谈和跟踪访问等形式,发现了理工类院校英语专业在课程设置上存在诸多问题,如课程设置缺少特色,各学期课程缺乏合理安排,专业英语课程师资不足,教材缺乏特色,社会实践环节薄弱等,并提出相应的对策,以优化课程设置,满足就业市场对复合型英语专业人才的需求。  相似文献   

损失规避下的指数跟踪问题及其粒子群算法求解     

李惊雷  胡支军 《贵州教育学院学报》2011,(6):6-10

随着指数衍生产品日益受到重视,指数化投资组合常被传统的消极基金管理者或机构所采用,而用有限的资金按指数构成比例进行投资显然是不现实的,所以指数的最优误差追踪就显得更加重要。将追踪误差定义为证券投资组合收益率与所追踪的指数基准收益率之差的均值平方和的平方根,建立了基数约束（即总资产数不超过某个特定整数K）下考虑投资者损失规避决策偏好的跟踪误差最小化模型,并设计了一个粒子群算法求解模型。实际算例表明,所构建的模型和算法是有效的。  相似文献   

氢原子光谱同位素谱线位移实验的参数优化     

张萍  袁学德  刘力军  曲艳玲 《实验室研究与探索》2011,30(10)

讨论了氢原子光谱实验中狭缝宽度、采集次数和负高压对氢原子光谱同位素位移谱线的影响,优化了氢原子光谱同位素位移实验的工作参数,获得了清晰的氢原子同位素位移光谱。通过该实验让学生掌握实验中多参数优化的方法,有利于加深学生对光谱理论的理解,有利于提高学生分析问题解决问题的能力。  相似文献   

薄壁结构件的加工工艺     

袁晓洲 《孝感职业技术学院学报》2011,(4):98-100

文章介绍了传统的薄壁结构件的加工方法及其缺陷,讨论了影响薄壁结构件加工精度的因素,提出了用高速切削加工典型薄壁结构件的方法,总结出当前机械制造业发展的方向是：努力发展数控切削技术,并向更高层次的自动化、柔性化、敏捷化、网络化和数字化制造方向推进。  相似文献   

Investigating the relationship between pre-service physics teachers' professional knowledge,self-concept,and interest     

Stefan Sorge  Melanie M. Keller  Knut Neumann  Jens Möller 《科学教学研究杂志》2019,56(7):937-955

This study investigates the relationships between professional knowledge, self-concept, and interest of pre-service physics teachers. In order to support student learning and interest development alike, teachers need a profound professional knowledge and respective motivational orientations. Developing both professional knowledge and motivational orientations in teachers is therefore a key challenge of teacher education. Prior research has focused on the development of content knowledge (CK) and pedagogical content knowledge (PCK) within teacher education, but the role of motivational orientations such as self-concept and interest have mostly been neglected areas of study. As individuals develop domain-specific motivational orientations, they compare their achievement in an external frame to the achievement of their peers, and they compare their achievements in an internal frame across domains. The effects of these psychological processes on domain-specific motivational orientations are described by the generalized internal/external frame of reference model (GI/E model). We assessed the professional knowledge (CK and PCK) and motivational orientations (self-concept and interest) of N = 200 pre-service physics teachers from 12 teacher education institutes in Germany. To investigate the predictions of the GI/E model, we utilized structural equation modeling. In line with the GI/E model, the analysis revealed that pre-service teachers use social comparisons. Pre-service teachers with a higher CK/PCK also showed a higher CK/PCK self-concept. We also identified instances of internal comparisons as we found that a high level of CK corresponds with a lower PCK self-concept. While we could not identify the same effects from professional knowledge on interest, self-concept mediated the effects from professional knowledge on interest. The results suggest that interdependencies between professional knowledge and motivational orientation should be given more consideration in teacher education research and should also be addressed more explicitly in teacher education.  相似文献   

数学建模优化程序设计与数学原理的综合运用     

王福来 《中国现代教育装备》2011,(17):64-65

从符号与数值的转化、同余映射中的周期长度及分阶段执行程序等3个方面,以实际例子研究了如何在实践中运用数学原理来优化程序设计、节约运行时间,达到利于解决数学建模问题的目标。  相似文献   

Unpacking teachers’ intentions to integrate technology: A meta-analysis     

《Educational Research Review》2019

The Technology Acceptance Model (TAM) is a key model describing teachers' intentions to use technology. This meta-analysis clarifies some of the contradictory findings surrounding the relations within the TAM for a sample of 45 studies comprising 300 correlations. We evaluate the overall fit of the TAM and its structural parameters, and quantify the between-sample variation through meta-analytic structural equation modeling. The TAM fitted the data well, and all structural parameters were statistically significant. On average, the TAM variables explained 39.2% of the variance in teachers' intentions to use technology. Several sample, measurement, and publication characteristics, including teachers’ experience and the representation of the TAM variables, moderated the relations within the TAM. Overall, the TAM represents a valid model explaining technology acceptance—however, the degree of explanation and the relative importance of predictors vary across samples. Implications for further research, in particular the generalizability of the TAM, are discussed.  相似文献   

论现代中国企业慈善行为的优化     

彭定光  胡丽明  彭军 《湖南城市学院学报》2011,32(3):1-7

现代中国企业为中国慈善事业作出了巨大贡献,但这种慈善行为仍然存在某些方面的缺失。企业应从内部和外部双向优化其慈善行为,一方面,通过提高企业的社会责任感、营造鼓励企业慈善行为的社会氛围和健全企业主动进行慈善行为的激励机制,来激发现代中国企业的慈善行为;另一方面,应树立现代中国企业应有的慈善理念和慈善态度。  相似文献   

日语专业课程体系的优化整合与学生自主学习能力的培养——以青岛理工大学为例     

王星  曹征 《青岛职业技术学院学报》2011,24(4):43-46

培养学生准确运用外语的能力是外语教学的重要目标。为此,青岛理工大学日语专业对培养计划等方面进行了一系列的改革,整合专业课程,重点培养学生的自主学习能力。学生是学习过程的主体和中心,教师则起到启发、帮助和引导作用。为了使学生更好地实现自主学习,教师在课堂内和课堂外都需要对学生加以适当的引导,以便使学生更快地适应角色的转换,由被动学习转为主动学习。  相似文献