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数字化信息系统实验室( Digital Information System Laboratory)(简称DISLab)的引入可以简化物理实验的操作、加快数据采集与处理的速度并提高精度,因此,将DISLab用于课堂演示和微课制作,可以使抽象的理论更加形象化、实验过程动态化,更易于学生对知识的理解和接受。本文以向心力研究实验为例,说明了通过DISLab实验的微课的设计和录制,可以训练物理师范生从学生视角出发,设计教学内容和教学思想、引导学生跟随实验过程进行思考,提高物理师范生的教学技能。 相似文献
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本文介绍了作者在工科力学教学中进行的三层次训练与考核,并阐述了它们在训练及培养学生探索未知的能力方面的重要作用。 相似文献
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When a special nonlinear self-feedback term is introduced into the dynamical equation of the backpropagation training algorithm for networks, the dynamics in weight space of networks can become chaotic. Chaotic dynamics of the system can help it escape from the most commonplace local minima of the energy. Simulation on the XOR problem and the prediction of chaotic time series have shown that the proposed chaotic training algorithm can converge to the global minimum or its approximate solutions efficiently and dramatically faster than the original backpropagation training algorithm. 相似文献
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Acoustic analysis techniques were used to investigate the short-term consequences of vocally violent behavior, and to compare voice production before and after training in hygienic laryngeal release (HLR) techniques. Twenty-seven actors ranging in age from 17 to 48 years were audiorecorded before and after multiple productions of 4 vocally violent behaviors: grunting, groaning, sobbing, and shouting. After training in HLR techniques, the experimental protocol was repeated. Audiorecordings of vowels (produced at 3 pitch levels: modal F0, minimum F0, maximum F0) before and after vocal violence, and before and after HLR training, were analyzed using the Multidimensional Voice Program (4305, Kay Elemetrics Corp, Lincoln Park, NJ). After vocal violence, no consistent acoustic changes were detected for voice generated at modal and minimum F0; however, significant increases in both fundamental frequency range and maximum F0 were observed. After training in HLR techniques, acoustic measures sensitive to pitch and amplitude perturbation, and non-harmonic noise, improved across pitch levels. The results also indicated that vocal training does defend the laryngeal system from undesirable changes related to vocally violent maneuvers that might surface at the extremes of an actor's pitch range. Because the HLR technique used in this investigation was multimodal, interesting questions are raised regarding which aspect of training is primarily responsible for the observed effects. Further study is required to identify such factors. 相似文献
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用前馈多层神经网络方法研究了高聚物的热力学性质.在本文的人工神经网络模型中,输入层为高聚物的密度ρ,缠结分子量M-e,玻璃化转变温度T-g,高聚物的高弹性模量G-N,钩状构像含量β和无扰均方末端距的特征比C-∞;输出层为高聚物比热C-p;隐含层的节点数为5.最后预测结果与实验结果非常接近,相对误差为2.2~5.4,这为研究高聚物的其它物理性质提供了一种新的方法. 相似文献
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Naveed Ahmad Khan Fahad Sameer Alshammari Carlos Andrs Tavera Romero Muhammad Sulaiman Ghaylen Laouini 《Molecules (Basel, Switzerland)》2021,26(23)
In this study, we have investigated the mathematical model of an immobilized enzyme system that follows the Michaelis–Menten (MM) kinetics for a micro-disk biosensor. The film reaction model under steady state conditions is transformed into a couple differential equations which are based on dimensionless concentration of hydrogen peroxide with enzyme reaction and substrate within the biosensor. The model is based on a reaction–diffusion equation which contains highly non-linear terms related to MM kinetics of the enzymatic reaction. Further, to calculate the effect of variations in parameters on the dimensionless concentration of substrate and hydrogen peroxide, we have strengthened the computational ability of neural network (NN) architecture by using a backpropagated Levenberg–Marquardt training (LMT) algorithm. NNs–LMT algorithm is a supervised machine learning for which the initial data set is generated by using MATLAB built in function known as “pdex4”. Furthermore, the data set is validated by the processing of the NNs–LMT algorithm to find the approximate solutions for different scenarios and cases of mathematical model of micro-disk biosensors. Absolute errors, curve fitting, error histograms, regression and complexity analysis further validate the accuracy and robustness of the technique. 相似文献
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高职院校实践教学平台的形式多样,校内生产性实训基地是其中之一。化学工程学院纯净水生产车间是陕西国防工业职业技术学院综合考虑化工专业的特殊性进行设计建设的。介绍了车间的设计与建设,描述了车间的运行及教学模式,认为车间的投入运行大大提高了学生的综合实践能力。 相似文献