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The memristor has broad application prospects in many fields, while in many cases, those fields require accurate impedance control. The nonlinear model is of great importance for realizing memristance control accurately, but the im- plementing complexity caused by iteration has limited the actual application of this model. Considering the approximate linear characteristics at the middle region of the memristance-charge (M-q) curve of the nonlinear model, this paper pro- poses a memristance controlling approach, which is achieved by linearizing the middle region of the M-q curve of the nonlinear memristor, and establishes the linear relationship between memristances M and input excitations so that it can realize impedance control precisely by only adjusting input signals briefly. First, it analyzes the feasibility for linearizing the middle part of the M-q curve of the memristor with a nonlinear model from the qualitative perspective. Then, the lin- earization equations of the middle region of the M-q curve is constructed by using the shift method, and under a sinusoidal excitation case, the analytical relation between the memristance M and the charge time t is derived through the Taylor series expansions. At last, the performance of the proposed approach is demonstrated, including the linearizing capability for the middle part of the M-q curve of the nonlinear model memristor, the controlling ability for memristance M, and the influence of input excitation on linearization errors. 相似文献
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高中物理实验是高考的重要考点,而在实验中合理应用图像解决问题更是热点.在高中物理实验中,各个物理量的关系错综复杂,多为非线性关系,因此,绘制出有关两个物理量的图像也多以曲线为主,很难利用图像解决实际问题.此文意从如何适当地转化物理量的形式,从而建立起它们之间的线性关系等相关问题进行研讨. 相似文献
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Jie He Jia-Sheng Yu Yan-Jie Hou Zuo-Yi Zhu Zhong-Ping Huang Mu-Hua Wang Nai-Fei Zhong Yan Zhu 《中国化学快报》2014,25(10):1392-1394
In this paper,a simple method based on ion chromatography(IC) with conductivity detection was developed for the determination of iminodiacetic acid(IDA) in the herbicide of glyphosate.Under optimized chromatographic conditions,good linear relationship,sensitivity and reproducibility were obtained.The detection limit(LOD) for IDA obtained by injecting 25 μL of sample was 31.8 μg/L(S/N = 3).Relative standard deviation(RSD) of repeated analysis for the peak areas was less than 1.53%(n = 6).A spiking study was performed with satisfactory recoveries between 92.8%and 103.6%.It was confirmed that this method could be applied in glyphosate products. 相似文献
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Quantum walks act in obviously different ways from their classical counterparts, but decoherence will lessen and close this gap between them. To understand this process, it is necessary to investigate the evolution of quantum walks under different decoherence situations. In this article, we study a non-Markovian decoherent quantum walk on a line. In a short time regime, the behavior of the walk deviates from both ideal quantum walks and classical random walks. The position variance as a measure of the quantum walk collapses and revives for a short time, and tends to have a linear relation with time. That is, the walker's behavior shows a diffusive spread over a long time limit, which is caused by non-Markovian dephasing affecting the quantum correlations between the quantum walker and his coin. We also study both quantum discord and measurement-induced disturbance as measures of the quantum correlations, and observe both collapse and revival in the short time regime, and the tendency to be zero in the long time limit. Therefore, quantum walks with non-Markovian decoherence tend to have diffusive spreading behavior over long time limits, while in the short time regime they oscillate between ballistic and diffusive spreading behavior, and the quantum correlation collapses and revives due to the memory effect. 相似文献
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1引言
在科学研究中,我们不但要了解一个变量的变化情况,更要进一步了解一个变量与另一个变量之间的关系.变量之间的常见关系有两种:一是确定性函数关系,变量之间的关系可以用函数表示;二是非确定性相关关系,变量之间有一定的关系,但不能完全用函数表达,变量间只存在统计规律.相关和回归是研究变量间线性关系的重要方法.但两者研究的角度不同.回归是研究变量间的因果关系的,力图把非确定性相关关系化归为确定的函数关系,达到通过自变量的已知值来预测因变量的未知值的目的. 相似文献