基于网络环境的大学物理实验教学改革研究与实践

本文结合我校大学物理实验课程改革的具体实际, 介绍了课程教学的设计理念和课程教学的组织模 式, 通过课程改革的运行, 总结出大学物理实验课程改革对人才培养发挥的作用, 指出了课程改革存在的问题, 以 及解决问题的方法     

新课程视野下大学物理教学改革策略分析

基础课程改革的不断深入展开，使大学课程的受众群体在知识结构、学习能力和学习方式等方面都与以往有了较大差异。本文以大学物理课程为例，通过对基础课程改革主要理念的简单介绍，从教学理念、教学组织、教学方法和学习评价四方面阐述大学课程应该如何改革，做好与基础课程的教学衔接。     

"综合科学课程"的困难和对策--重读《科学课程论》

《基础教育课程改革纲要（试行）》中规定，在小学阶段，主要以开设综合课程为主；在初中阶段，综合课程与分科课程的开设并重．我国已经进入基础教育课程改革的第五个年头，但综合课程（特别是综合科学课程）在全国范围内的发展并不尽如人意，至今综合科学课程主要集中在少量国家级课程改革实验区实验（浙江省除外），     

贫困地区中学物理教学如何落实新课程理念

贫困地区和农村中学的课程改革面临诸多困境，而贫困地区的课程改革能否推进，直接影响着整个基础教育改革的推进．笔者处在贫困地区，对本地区十几所中学(包括市、县级重点中学和农村中学)进行了认真细致的调查研究，通过分析物理教学现状，提出了一些推进课程改革、落实新课程理念的设想，愿能抛砖引玉，从真正意义上推进新一轮课程改革．     

物理实验室课程资源的开发

实验是以实验室为基地的教学活动．2002年部颁的普通高中《物理课程标准》（以下简称：新课标）针对实验教学愈来愈凸现的重要性，指出：“实验是物理课程改革的重要环节，是落实物理课程目标、全面提高学生科学素养的重要途径，也是物理课程改革的重要资源．”把“实验”作为“物理课程改革的重要资源”的这一提法，在历次大纲中是前所未有的，给我们从事物理实验教学的教师提出了一个实验教学改革更深层次的要求，所以物理实验室课程资源的开发与利用是课程改革的重要部分．以下是笔者实施新课标以来在实验教学实践中利用开发物理实验室课程资源的一些做法．     

立体化、创新型的光学课程教学体系与模式的研究

为了培养高水平的创新型人才,我们从精选课程教学内容、运用现代化的教学手段以及改革考核方式等方面对光学课程作了改革,取得了良好的教学效果.     

新课程理念下高师《中学物理教学论》课程的改革与实践

面对全球基础教育改革浪潮，2001年国家教育部颁布了《基础教育课程改革纲要（试行）》，调整和改革基础教育的课程体系、结构、内容，构建符合素质教育要求的新的课程体系．课程改革对中学教师的教育理念、教学行为、知识结构等方面都提出了严峻的挑战．因此，高师院校的《中学物理教学论》系列课程，应积极地调整培养目标、课程结构、课程内容，改革教学方法，培养适应时代发展要求、推进素质教育实施的新型的物理教师．     

利用多媒体技术完善《模拟电子技术》课程教学手段的改革

探讨了利用多媒体技术进行《模拟电子技术》课程教学手段改革的必要性 ,多媒体技术的发展为《模拟电子技术》课程教学手段改革带来的启示 ,科学有效地使用多媒体是教学手段改革的关键。多媒体技术在教学领域中使用存在的问题及其展望。     

探讨物理实验教学融合S T EAM 理念的几种方法

把美国作为中国教育界的关注对象, 研究其教育科研成果, 促进中国的教育课程改革, 是我国基础教 育改革的途径之一. 当前美国课程改革中, S T EAM 教育是其基础教育改革的重点. 近些年的课程发展中, 提出了不 少可行性高、 课程资源完整的解决方案. 然而,这些解决方案仍然存在很多实践上的限制条件. 笔者通过研究美国 课程改革中运用的 S T EAM 教育理念,并通过在物理实验教学中,不断实践与总结,探讨并提出了几种融合 S T EAM 理念的方法     

浅谈物理专业太阳能发电方向的课程群设置和实施

课程群是为完善同一施教对象的认知结构和优化资源,而将本专业或跨专业培养方案中若干门在知识、方法、问题等方面有逻辑联系的课程加以整合而成的课程体系.本文浅谈了上海电力学院物理专业面向太阳能专业方向的课程群的设置以及改革的原因和必要性,以此课程群为依托,努力优化了教学内容,完善了实践和实习基地,建立了一整套创新能力拓展平台,尝试改革了课程群内课程的考核方式,取得了一定改革成效,提高了学生的创新能力,毕业生得到了用人单位的一致好评.     

A methodology to achieve the basis function for the expansion of sound speed profile

In order to evaluate the reliability and applicability of the Empirical Orthogonal Functions（EOFs）in the acoustic inversion of sound speed profile（SSP）and reduce EOF＇s dependence on the sample data,a methodology is proposed for the achievement of the basis functions for SSP＇s expansion.By analyzing the oceanographic dynamics which is the main cause of the SSP＇s variation,the basis functions are obtained naming the Hydrodynamic Normal Modes（HNMs）.The HNM basis functions are almost the same as those derived from the EOF method,while HNMs has less dependence on the amount of the sample data.HNMs method has a physically meaningful interpretation,and it could give out the physical parameters which determine the basis functions for the expansion of SSP,and this makes it possible to analyze and evaluate the trustiness and applicability of EOFs.     

Theoretical analysis and simulation of conjugate heights for dual-conjugate AO system in lidar

A multi-conjugate adaptive optics （MCAO） can offer a possibility of widening field of view （FOV） characterized by the isoplanatic angle, and the choose of conjugate height becomes a basic problem for MCAO, which influences the size of iosplanatic angle. Considering the application of lidar, the isoplanatic angle＇s expressions of two deformable mirrors （DMs） MCAO for uplink and downlink are deduced. The effects of conjugate heights for dual-conjugate AO are thoughtfully discussed, and the isoplanatic angles are further analyzed. The results show that the isopanatic angle varies with the conjugate height and reaches the maximum as the conjugate height is at the optimal altitude. Moreover, the optimal conjugate height changes with the propagation distance.     

Modeling of the RF system for the normal conducting linac

To study the new RF control methods, a mathematic model of the RF system for the normal conducting linac is built and implemented with the software of Matlab. The model contains some typical units of the RF system, such as the klystron, the SLED and the traveling wave accelerating tube. Finally, the model is used to study the working point of the SLED and the adaptive feed forward algorithm for the RF control system. Simulation shows that the model works well as expected.     

Voltage-controlled optical filter based on electrowetting

In this letter, we propose a voltage-controlled optical filter based on electrowetting. The device is made of a transparent cubic cell filled with two immiscible liquids having three indium tin oxide electrodes fabricated on the bottom substrate of the cell. A conductive droplet carrying a color filter is placed on the ITO electrode and the surrounding liquid is density-matched silicone oil. Under zero bias, the droplet is placed in the middle of the substrate and white light passes through the filter and we can see red light on the screen. When a voltage is applied to the device, the filter moves with the liquid based on electrowetting effect, we can see the white light on the screen. Due to the movement of the liquid, our device functions as an optical switcher. The switch time of the device is ~70 ms. The proposed device has a wide application in optical communication, electronic display, and optical switch.     

Experimental study on SC RF cavities by using China large grain niobium for ILC

Large grain niobium has the potential of simplifying the production sequence and consequently reducing the cost of the superconducting RF cavities for ILC.To investigate the feasibility of fabrication and the possibility to achieve high gradient by large grain cavities,two 1.3 GHz cavities were made of China large grain niobium and a series of vertical tests were carried out following several different surfaces treatment procedures.Two cavities have both reached the high gradient of more than 43 MV/m repeatedly and the maximum accelerating field of 47.9 MV/m has been achieved by China large grain niobium.This paper introduces the features of the fabrication and surface treatments on the large grain cavities and presents the preliminary results of the research.     

Influence of purity of HfO2 on reflectance of ultraviolet multilayer

The impurities in two kinds of HfO2 materials and in their corresponding single layer thin films were determined through glow discharge mass spectrum technology and secondary ion mass spectrometry(SIMS) equipment respectively.It was found that ZrO2 was the main impurity in the two kinds of HfO2 either in the original HfO2 materials or in the electron beam deposited films.In addition,the difference of Zr content in the two kinds of HfO2 single laver films was much laxger than that of the other impurities such as Ti and Fe.which showed that it was just ZrO2 that made the difference between the optical performance of the film products including the two kinds of HfO2.With these two kinds of HfO2 and the same kind of SiO2.we deposited HfO2/SiO2 multilayer reflective coatings at the wavelength of 266 nm.Experimental results showed that the reflectances of these two mirrors were about 99.85% and 99.15% respectively,which agreed well with the designed results what were based on the optical constants obtained from the corresponding single layer thin films.     

Matched wavelength and incident angle for the diagnostic beam to achieve coherent grating tiling

Design and operation of a practical, accurate alignment diagnostic system is important for the grating tiling technology, which is supposed to be applied in a chirped-pulse amplification system to increase the output power. A diagnostic method is proposed and demonstrated for grating tiling. Provided that the wavelength and incident angle of the diagnostic beam are properly set, the far-field of the main laser beam and that of the diagnostic beam can vary in the same way with the tiling errors between the sub-aperture gratings. Therefore, rotational and translational errors can be controlled and compensated according to the far-field of the diagnostic beam. The real-time monitoring and alignment can be achieved without disturbing the main beam.     

A modified voice conversion algorithm using compressed sensing

A voice conversion algorithm,which makes use of the information between continuous frames of speech by compressed sensing,is proposed in this paper.According to the sparsity property of the concatenated vector of several continuous Linear Spectrum Pairs（LSP）in the discrete cosine transformation domain,this paper utilizes compressed sensing to extract the compressed vector from the concatenated LSPs and uses it as the feature vector to train the conversion function.The results of evaluations demonstrate that the performance of this approach can averagely improve 3.21%with the conventional algorithm based on weighted frequency warping when choosing the appropriate numbers of speech frame.The experimental results also illustrate that the performance of voice conversion system can be improved by taking full advantage of the inter-frame information,because those information can make the converted speech remain the more stable acoustic properties which is inherent in inter-frames.     

Acoustic performance prediction of Helmholtz resonator with conical neck

There is no accurate analytical approach for the acoustic performance prediction of Helmholtz resonator with conical neck,which has broad band acoustic attenuation performance in the low frequency range.To predict the acoustic performance of the resonator accurately,a general theory model based on the one-dimensional analysis approach with acoustic length corrections is developed.The segmentation method is used to calculate the acoustic parameters for sound propagation in conical tubes.And then,an approximate formula is deduced to give accurate correction lengths for conical tubes with difierent geometries.The deviations of the resonance frequency between the transmission loss results obtained by the general theory with acoustic lengths correction and the results from the finite element method and experiments are less than 2 Hz,which is much better than the results from one-dimensional approach without corrections.The results show that the method of acoustic length correction for the conical neck greatly improved the accuracy of the one-dimensional analysis approach,and it will be quick and accurate to predict the sound attenuation property of Helmholtz resonator with conical neck.     

Cooling induced by parametric resonance in a magnetic quadrupole trap

It is demonstrated experimentally that the anharmonic property of the quadrupole trap can be exploited to cool trapped atoms by modulating the trap potential anisotropically.This cooling effect arises from the energy-selective removal of the most energetic trapped atoms and the thermal equilibrium of the remaining atoms.The frequency dependences of the temperature and the fraction of the atoms left in the trap after the modulation are explored.It is also demonstrated that the cooling induced by parametric resonance can also increase the phase space density of the trapped atoms.