大学基础课程实验教学方案设计的研究与实践

本文探讨了大学基础课程实验教学方案设计的内容和方法,并对常见的实验教学方式进行了界定,以我校开设的《物理学实验》为例,对大学基础课程实验教学方案进行了设计,该研究不仅能进一步提高《物理学实验》的教学效果,也为大学基础课程实验教学方案的设计提供了参考与借鉴。     

高校大学物理创新实验的设计与实践

就如何高效地培养大学生的创新创业能力问题,提出如何设计大学物理创新实验课程。并分别从大学物理创新实验课程开展的必要性及大学物理创新课程的设计和实践过程几个方面进行具体阐述。     

基于课程思政指导的后疫情时期结构力学融合教学探索

在课程思政指导下,对结构力学课程的教学组织进行优化设计。深入挖掘行业中符合卓越工程师和工匠精神的思政元素,并设计课程案例。后疫情条件下,设计线上和线下同步教学的学习模式,并在教学中对师生隔离保护提出具体方案。通过对课程实验的分析,精心设计在线实验课程培养学生的动手实践能力;通过教学培养学生的自信心和责任感,激发学习兴趣,也保障了疫情条件下的学习效果。     

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     

以培养工程创新能力为核心的实验课教学改革与实践

本文以《高等光电技术实验》课程中的"激光陀螺技术"实验模块为例,介绍了在实验内容设计、教学方法和手段、教师队伍建设等方面进行的教学改革与实践,初步达到了利用综合性实验课程培养学生工程创新能力的目标。     

浅谈大学物理设计性实验中信息技术的应用

大学物理课程实验是培养学生实验能力、科学研究思维的重要课程.因此研究和分析如何改善我国大学物理实验教学水平,就显得尤为重要了.本文主要从设计性物理实验对于大学生教学的主要意义和必要性入手,阐述了如何运用信息技术手段,不断的开展和完善大学物理设计性实验教学工作,以期为大学物理实验教学提供新的思路.     

关于开设物理设计性实验课的几点体会

本文主要是围绕大学物理实验课程中的设计性实验作了一些有益的探讨。     

大学物理实验教学内容与模式的改革与探索

大学物理实验课程对于培养理工科大学生动手能力和理论联系实际的综合能力具有不可替代的作用。针对教学过程中发现的一些问题,借鉴近几年我校成功举办的大学生物理学术竞赛活动的经验,提出了改革大学物理实验课程的方法。强调应注重开放设计性、研究性实验课程的引入,并优化教学模式和课程考核方式。     

电磁学实验课程教学创新设计

电磁学实验课程是物理学专业的一门学科基础课程,要求学生掌握电磁学常用仪器的基本原理和调试方法,使学生对基本的电磁学实验思想和方法等有一定程度的理解和认识,为进一步的理论学习、实验训练和科学研究打下坚实的基础.结合吉林师范大学的教学实践,对电磁学实验课程的教学进行了创新设计.     

一个传统验证性实验向设计性实验的升华

本文通过探讨单缝夫琅禾费衍射实验的原理、特点、传统实验的排布方式,在深入领会《理工科非物理专业大学物理实验课程教学基本要求》的基础上,研发了＂单缝衍射与现代传感器的设计＂实验,实现了一个传统的验证性实验向设计性实验的升华.文中给出了该实验的教学环节安排,提出了一些需要注意的技术细节,并给出了几个设计实例,最后还给出了设计该实验的一些体会.     

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.     

Quick single-photon detector with many avalanche photo diodes working on the time division

Due to the limit of response speed of the present single-photon detector, the code rate is still too low to come into practical use for the present quantum key distribution (QKD) system.A new idea is put up to design a quick single-photon detector.This quick single-photon detector is composed of a multi-port optic-fiber splitter and many avalanche photo diodes (APDs).Au of the ports with APDs work on the time division and cooperate with a logic discriminating and deciding unit driven by the clock signal.The operation frequency lies on the number N of ports, and can reach N times of the conventional single-photon detector.The single-photon prompt detection can come true for high repetition-rate pulses.The applying of this detector will largely raise the code rate of the QKD, and boost the commercial use.     

Characterization of PolyA and PolyC mismatches by Raman spectroscopy

A.C mismatches are studied by Raman spectral characterization of PolyA, PolyC, and their equimolar complex in solution of 0.14 mol/L Na ,pH7.0.Experimental results show that A·C mismatches occur to be A/B (mainly A) conformers, and unlike Watson-Crick base pairing, this kind of mismatches is stabilized by only one hydrogen bond involving cytosine N4H2 and adenine N7.The formation of A·C complex makes the base stacking interactions much stronger, and conformation of the backbone more ordered, which leads to obvious Raman hypochromic effect with some shifts in corresponding bands.     

Improvement of four-wave mixing-based wavelength conversion efficiency in dispersion shifted fiber by 40-GHz clock pumping

40-GHz clock modulated signal as a pump to improve the efficiency of four-wave mixing (FWM)-based wavelength conversion in a 26.5-km dispersion shifted fiber (DSF) is investigated. The experimental results demonstrate that the conjugated FWM component has higher intensity with the clock pumping than that with the continuous-wave (CW) light pumping. The improvement of FWM-based wavelength conversion efficiency is negligible when the pump power is less than Brillouin threshold. But when the pump power is greater than Brillouin threshold, the improvement becomes significant and increases with the increment of pump power. The improvement can increase up to 9 dB if pump power reaches 17 dBm.     

Multi-pulse operation of a Kerr-lens mode-locked femtosecond laser

Our experimental results show that the presence of a proper amount of negative group velocity dispersion is essential to multi-pulse operation of a Kerr-lens mode-locked femtosecond laser. We demonstrate that the pulse separations and the number of pulses contained within a cavity round trip are strongly dependent on the initial perturbations. The results allow us to get a better understanding on the influences of the convoluted self-phase modulation and intra-cavity dispersions on the stable multi-pulse oscillation in a Kerr-lens mode-locked femtosecond laser.     

Propagation of Helmholtz-Gauss beams in weak turbulent atmosphere

Based on the Rytov approximation of light propagation in weak turbulent atmosphere,the closed-form expressions of field and average irradiance of each one of the four fundamental families of Helmholtz-Gauss (HzG)beams:cosine-Gauss beams,stationary Mathieu-Gauss beams,stationary parabolic-Gauss beams,and Bessel-Gauss beams,which are propagating in weak turbulent atmosphere,are obtained.The results show that the field and average irradiance can be written as the product of four factors:complex amplitude depending on the z-coordinate only,a Ganssian beam.a factor of complex phase perturbation induced by atmospheric turbulence,and a complex scaled version of the transverse shape of the non-diffracting beam.The effect of weak atmospheric turbulence on irradiance distribution of the HzG beam can be ignored.     

An effective method for reducing speckle noise in digital holography

An effective method for reducing the speckle noise in digital holography is proposed in this paper.Different from the methods based on classical filtering technique,it utilizes the multiple holograms which are generated by rotating the illuminating light continuously.The intensity images reconstructed by a series of holograms generated by rotating the illuminating light possess different speckle patterns.Hence by properly averaging the reconstructed intensity fields,the speckle noises can be reduced greatly.Experimental results show that the proposed method is simple and effective to reduce speckle noise in digital holography.     

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.     

Speech enhancement by array crosstalk resistant ANC and spectrum subtraction

Microphone array-based speech enhancement has great importance for speech communications and speech recognition. To reduce the aperture of the microphone array and to increase the effect of the speech enhancement will greatly broaden the application areas of the microphone array. An array crosstalk resistant adaptive noise cancellation method is therefore presented. And then an improved spectral subtraction algorithm is further cascaded to obtain better enhancement results. Theoretic analysis and experiments indicate that the proposed scheme needs only a very small microphone array while it simultaneously achieves a higher SNR improvement. Besides, the proposed scheme can be used in many noisy environments and is easy for real-time implementation.