利用线阵CCD的迈克尔逊干涉仪测量压电材料的压电系数

将压电陶瓷片固定在迈克尔逊干涉仪的移动镜上,当加在压电陶瓷片上的驱动直流电压增加时,引起压电陶瓷的微小伸长进而引起移动镜的移动,引起光屏上干涉条纹环数目的变化;用线阵CCD(charge coupled device)作为光电传感器件捕捉干涉条纹的光强信号,再将电信号进行模数转换,采取USB接口与微机接口,用C++语言编写程序设计了一种新型的条纹自动计数软件,将这种计数方法与压电系数的测量结合起来,可以自动得出其压电系数.     

我国高中生科学素质影响因素分析

高中生是我国科技后备人才的主力军,其科学素质直接关系到我国未来科技水平,因此探讨我国高中生科学素质的影响因素,对于提高我国科技后备人才科学素质进而提升我国科技水平具有重要意义。本文利用我国高中生大规模基线调查数据,基于教育生产函数模型,分析了我国高中生科学素质的影响因素,结果表明:竞赛因素对高中生科学素质有显著影响,班级同伴因素有较大影响,学校因素有很大影响,而家庭因素有重要影响。为此,首先,应重视不断增强科技竞赛和学科竞赛活动对高中生科学素质的提升作用,缩小班级规模、加强合作学习,从而更好地发挥班级同伴效应对于促进高中生科学素质提升的作用;其次,要引导家长形成科学的教育方式,促进高中生科学素质的提高。此外,需要加强中小学科学教育过程中对学生科学素质培养的渗透,重点关注提高西部地区和非重点校高中生科学素质问题。     

Stabilization of Delayed Networks with Different Nodes

In this paper,the control of complex delayed networks with different nodes is proposed.Firstly,the stabilization of coupled networks with time delay is investigated.By constructing a Lyapunov function,a linear feedback controller design procedure for the networks is converted to the problem of solving a set of linear matrix inequalities.Then the results are extended to networks with both delayed dynamical nodes and delayed couplings.It is shown that the stabilization of complex networks is determined by the dynamics of each uncoupled node,coupling matrix and feedback gain matrix of networks.Two examples are simulated.In the first example,a network with 10 nodes consisting of Lorenz systems and systems proposed by Zhang in 2009 is given.It is found that the network states are divergent without control,and convergent under designed linear feedback controllers.In the second example,a larger network with 100 nodes consisting of delayed Chen systems and delayed Lorenz systems is given.The proposed method is also effective for large scale networks.     

广义线性模型极大似然估计弱相合性的数值模拟

广义线性模型是经典线性模型的自然推广,它是一类应用广泛的统计模型.选择Probit模型,利用matlab编程,通过数值模拟的方法验证了广义线性模型的极大似然估计的弱相合性.     

基于Maple的理论力学教学实践

利用Maple强大的符号与可视化功能,方便、快捷、形象、直观地求解了理论力学中的几个具体问题,实现了基于Maple的理论力学可视化教学.Maple在数值计算和数据可视化方面具有较强的能力和特色,能简单、快捷地处理理论力学中自由落体偏东微分方程的求解,有限长度线段引力场的场强和引力势的计算问题,并同时绘制出数值解的2D、3D图形.列举了傅科摆的运动轨迹、洛伦茨方程求解计算的可视化结果,给出了洛伦茨方程求解的Maple程序.具体实例表明,用Maple来完成微分方程的求解和数值计算,实现复杂运动过程和计算结果的形象直观化,便于对各种初始条件下各变量的关系进行比较分析.对于物理教学提供了一种方便、快捷地实现可视化教学的方法.     

微小长度变化量的实验研究

总结了光杠杆放大法、千分表测量法、光的干涉测量法和光的衍射测量法测量微小长度变化量的方法,通过对实验装置进行相应的改造与组装,并用其测量原理和方法以及相关的实验装置对金属受热时的微小伸长量及线胀系数进行了相应的测定,同时对实验结果和误差进行了比较与分析。实验表明,4种测量方法中千分表测量法的相对误差和标准偏差均接近最小值,是4种方法中最理想的测量方法。该实验也有利于激发学生的创新意识,培养他们的研究潜能。     

基于PSO和多元线性回归的奥运会奖牌预测分析

针对传统奥运会成绩预测模型中存在的不足,提出一种将PSO和多元线性回归分析相结合的预测模型。分析多元线性回归和PSO算法后,结合体育比赛的特点,通过PSO优化迭代计算,确定奖牌统计模型中各回归系数,建立了奥运会参赛国成绩与回归系数之间复杂的非线性关系。利用Matlab对建立奖牌模型进行了验证,预测精度高。     

圆形镜平面腔数值迭代计算

从菲涅尔-基尔霍夫积分衍射方程出发,推导了圆形镜平面腔所满足的自再现模迭代方程,给出了数值迭代方程的具体形式和TEM00、TEM01、TEM10 3个模式的具体迭代方法。分析计算了3个自再现模的形成过程、单程损耗及相位等特性,并比较了不同菲涅尔数时各模式的本征值和衍射损耗。该方法为研究圆形平面镜谐振腔的激光模式、损耗特性及相位提供了可靠的理论方法,具体的数值迭代方法也可推广应用到其他类型的谐振腔。     

Grover量子搜寻算法的线性光学实现

利用线性光学元件和单光子来编码量子比特,可给出Grover量子搜寻算法的光学实现方案。该方案可以推广到多个量子比特的情况。     

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

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.