A novel approach for constructing robust Mamdani fuzzy system was proposed, which consisted of an efficiency robust estimator(partial robust M-regression, PRM) in the parameter learning phase of the initial fuzzy syst...A novel approach for constructing robust Mamdani fuzzy system was proposed, which consisted of an efficiency robust estimator(partial robust M-regression, PRM) in the parameter learning phase of the initial fuzzy system, and an improved subtractive clustering algorithm in the fuzzy-rule-selecting phase. The weights obtained in PRM, which gives protection against noise and outliers, were incorporated into the potential measure of the subtractive cluster algorithm to enhance the robustness of the fuzzy rule cluster process, and a compact Mamdani-type fuzzy system was established after the parameters in the consequent parts of rules were re-estimated by partial least squares(PLS). The main characteristics of the new approach were its simplicity and ability to construct fuzzy system fast and robustly. Simulation and experiment results show that the proposed approach can achieve satisfactory results in various kinds of data domains with noise and outliers. Compared with D-SVD and ARRBFN, the proposed approach yields much fewer rules and less RMSE values.展开更多
The atomic force microscope(AFM)can measure nanoscale morphology and mechanical properties and has a wide range of applications.The traditional method for measuring the mechanical properties of a sample does so for th...The atomic force microscope(AFM)can measure nanoscale morphology and mechanical properties and has a wide range of applications.The traditional method for measuring the mechanical properties of a sample does so for the longitudinal and transverse properties separately,ignoring the coupling between them.In this paper,a data processing and multidimensional mechanical information extraction algorithm for the composite mode of peak force tapping and torsional resonance is proposed.On the basis of a tip–sample interaction model for the AFM,longitudinal peak force data are used to decouple amplitude and phase data of transverse torsional resonance,accurately identify the tip–sample longitudinal contact force in each peak force cycle,and synchronously obtain the corresponding characteristic images of the transverse amplitude and phase.Experimental results show that the measured longitudinal mechanical characteristics are consistent with the transverse amplitude and phase characteristics,which verifies the effectiveness of the method.Thus,a new method is provided for the measurement of multidimensional mechanical characteristics using the AFM.展开更多
永磁同步电机因其结构紧凑、噪声较少、功耗较少、运行速度快、操作稳定,已被普遍采用。针对永磁同步电机弱磁控制过程中,转速环参数选取采用传统PI(proportional-integral)控制方法,依靠经验整定参数,外界抗干扰能力较差、难以保证在...永磁同步电机因其结构紧凑、噪声较少、功耗较少、运行速度快、操作稳定,已被普遍采用。针对永磁同步电机弱磁控制过程中,转速环参数选取采用传统PI(proportional-integral)控制方法,依靠经验整定参数,外界抗干扰能力较差、难以保证在各运行区间具有优良性能等问题,提出了一种基于减法平均优化算法的永磁同步电机的弱磁和MTPA(maximum torque per ampere)控制的宽运行范围方法。将智能寻优算法、MTPA控制、弱磁控制三者相结合,利用减法平均优化算法优化PI控制器的参数,提高了系统的响应性能和抗干扰能力;工作电压未超过电压极限圆使用MTPA控制策略运行;工作电压超过电压极限圆利用电压闭环反馈,进行弱磁控制。使用MATLAB/Simulink构建的永磁同步电机弱磁控制仿真模拟,通过PI控制器和减法平均优化算法优化后的PI控制器性能对比,从仿真结果得到控制器方法的有效性。实验有效证明了该控制方法能够解决各种运行工况下控制器参数的优化整定问题,提高电机控制精度。展开更多
基金Project(61473298)supported by the National Natural Science Foundation of ChinaProject(2015QNA65)supported by Fundamental Research Funds for the Central Universities,China
文摘A novel approach for constructing robust Mamdani fuzzy system was proposed, which consisted of an efficiency robust estimator(partial robust M-regression, PRM) in the parameter learning phase of the initial fuzzy system, and an improved subtractive clustering algorithm in the fuzzy-rule-selecting phase. The weights obtained in PRM, which gives protection against noise and outliers, were incorporated into the potential measure of the subtractive cluster algorithm to enhance the robustness of the fuzzy rule cluster process, and a compact Mamdani-type fuzzy system was established after the parameters in the consequent parts of rules were re-estimated by partial least squares(PLS). The main characteristics of the new approach were its simplicity and ability to construct fuzzy system fast and robustly. Simulation and experiment results show that the proposed approach can achieve satisfactory results in various kinds of data domains with noise and outliers. Compared with D-SVD and ARRBFN, the proposed approach yields much fewer rules and less RMSE values.
基金This project is supported by the General Program of the National Natural Science Foundation of China(62073227)the National Natural Science Foundation of China(61927805 and 61903359).
文摘The atomic force microscope(AFM)can measure nanoscale morphology and mechanical properties and has a wide range of applications.The traditional method for measuring the mechanical properties of a sample does so for the longitudinal and transverse properties separately,ignoring the coupling between them.In this paper,a data processing and multidimensional mechanical information extraction algorithm for the composite mode of peak force tapping and torsional resonance is proposed.On the basis of a tip–sample interaction model for the AFM,longitudinal peak force data are used to decouple amplitude and phase data of transverse torsional resonance,accurately identify the tip–sample longitudinal contact force in each peak force cycle,and synchronously obtain the corresponding characteristic images of the transverse amplitude and phase.Experimental results show that the measured longitudinal mechanical characteristics are consistent with the transverse amplitude and phase characteristics,which verifies the effectiveness of the method.Thus,a new method is provided for the measurement of multidimensional mechanical characteristics using the AFM.
文摘永磁同步电机因其结构紧凑、噪声较少、功耗较少、运行速度快、操作稳定,已被普遍采用。针对永磁同步电机弱磁控制过程中,转速环参数选取采用传统PI(proportional-integral)控制方法,依靠经验整定参数,外界抗干扰能力较差、难以保证在各运行区间具有优良性能等问题,提出了一种基于减法平均优化算法的永磁同步电机的弱磁和MTPA(maximum torque per ampere)控制的宽运行范围方法。将智能寻优算法、MTPA控制、弱磁控制三者相结合,利用减法平均优化算法优化PI控制器的参数,提高了系统的响应性能和抗干扰能力;工作电压未超过电压极限圆使用MTPA控制策略运行;工作电压超过电压极限圆利用电压闭环反馈,进行弱磁控制。使用MATLAB/Simulink构建的永磁同步电机弱磁控制仿真模拟,通过PI控制器和减法平均优化算法优化后的PI控制器性能对比,从仿真结果得到控制器方法的有效性。实验有效证明了该控制方法能够解决各种运行工况下控制器参数的优化整定问题,提高电机控制精度。
