This paper presents a modeling method for a non-uniformly sampled system bused on support vector regression （ SVR ）. First, a lifted discrete-time state-space model for a non-uniformly sampled system is derived by u...This paper presents a modeling method for a non-uniformly sampled system bused on support vector regression （ SVR ）. First, a lifted discrete-time state-space model for a non-uniformly sampled system is derived by using the lifting technique to reduce the modeling difficulty caused by multirate sampling. Then, the system is divided into several parallel subsystems and their input-output model is presented to satisfy the SVR model. Finally, an on-line SVR technique is utilized to establish the models of all subsystems to deal with uncertainty. Furthermore, the presented method is applied in a multichannel electrohydraulic force servo synchronous loading system to predict the system outputs over the control sample interval and the prediction mean absolute percentage error reaches 0. 092%. The results demonstrate that the presented method has a high modeling precision and the subsystems have the same level of prediction error.展开更多
多维核磁共振(Nuclear Magnetic Resonance,NMR)利用多维波谱来分析分子结构,被广泛用于化学、生物学和医学等领域,但信号采样时间随波谱维度和采样点数增加而迅速增长.非均匀采样通过降低间接维采样点数来加速数据采集,并引入合理的重...多维核磁共振(Nuclear Magnetic Resonance,NMR)利用多维波谱来分析分子结构,被广泛用于化学、生物学和医学等领域,但信号采样时间随波谱维度和采样点数增加而迅速增长.非均匀采样通过降低间接维采样点数来加速数据采集,并引入合理的重建方法获得完整的NMR波谱.如何快速重建高质量的波谱,是NMR信号处理研究的前沿.本文主要综述近年来基于低秩矩阵的NMR波谱重建方法的发展.首先介绍了低秩矩阵的相关数学基础;然后从一般低秩矩阵和结构化低秩汉克尔矩阵两个角度来论述重建模型,并讨论相关的NMR波谱应用;最后分析了该技术存在的不足,并展望其未来发展的趋势.展开更多
The studying motivation of this paper is that there exist many modeling issues of nonuniformly sampling nonlinear systems in industrial systems.Based on multi-model modeling principle,the corresponding model of non-un...The studying motivation of this paper is that there exist many modeling issues of nonuniformly sampling nonlinear systems in industrial systems.Based on multi-model modeling principle,the corresponding model of non-uniformly sampling nonlinear systems is described by the nonlinear weighted combination of some linear models at local working points.Fuzzy modeling based on multimodel scheme is a common method to describe the dynamic process of non-linear systems.In this paper,the fuzzy modeling method of non-uniformly sampling nonlinear systems is studied.The premise structure of the fuzzy model is confirmed by GK fuzzy clustering,and the conclusion parameters of the fuzzy model are estimated by the recursive least squared algorithm.The convergence perfromance of the proposed identification algorithm is given by using lemmas and martingale theorem.Finally,the simulation example is given to demonstrate the effectiveness of the proposed method.展开更多
In this paper a recursive state-space model identification method is proposed for non-uniformly sampled systems in industrial applications. Two cases for measuring all states and only output(s) of such a system are co...In this paper a recursive state-space model identification method is proposed for non-uniformly sampled systems in industrial applications. Two cases for measuring all states and only output(s) of such a system are considered for identification. In the case of state measurement, an identification algorithm based on the singular value decomposition(SVD) is developed to estimate the model parameter matrices by using the least-squares fitting. In the case of output measurement only, another identification algorithm is given by combining the SVD approach with a hierarchical identification strategy. An example is used to demonstrate the effectiveness of the proposed identification method.展开更多
文摘This paper presents a modeling method for a non-uniformly sampled system bused on support vector regression （ SVR ）. First, a lifted discrete-time state-space model for a non-uniformly sampled system is derived by using the lifting technique to reduce the modeling difficulty caused by multirate sampling. Then, the system is divided into several parallel subsystems and their input-output model is presented to satisfy the SVR model. Finally, an on-line SVR technique is utilized to establish the models of all subsystems to deal with uncertainty. Furthermore, the presented method is applied in a multichannel electrohydraulic force servo synchronous loading system to predict the system outputs over the control sample interval and the prediction mean absolute percentage error reaches 0. 092%. The results demonstrate that the presented method has a high modeling precision and the subsystems have the same level of prediction error.
文摘多维核磁共振(Nuclear Magnetic Resonance,NMR)利用多维波谱来分析分子结构,被广泛用于化学、生物学和医学等领域,但信号采样时间随波谱维度和采样点数增加而迅速增长.非均匀采样通过降低间接维采样点数来加速数据采集,并引入合理的重建方法获得完整的NMR波谱.如何快速重建高质量的波谱,是NMR信号处理研究的前沿.本文主要综述近年来基于低秩矩阵的NMR波谱重建方法的发展.首先介绍了低秩矩阵的相关数学基础;然后从一般低秩矩阵和结构化低秩汉克尔矩阵两个角度来论述重建模型,并讨论相关的NMR波谱应用;最后分析了该技术存在的不足,并展望其未来发展的趋势.
基金the National Natural Science Foundation of China under Grant Nos.61863034and 51667021。
文摘The studying motivation of this paper is that there exist many modeling issues of nonuniformly sampling nonlinear systems in industrial systems.Based on multi-model modeling principle,the corresponding model of non-uniformly sampling nonlinear systems is described by the nonlinear weighted combination of some linear models at local working points.Fuzzy modeling based on multimodel scheme is a common method to describe the dynamic process of non-linear systems.In this paper,the fuzzy modeling method of non-uniformly sampling nonlinear systems is studied.The premise structure of the fuzzy model is confirmed by GK fuzzy clustering,and the conclusion parameters of the fuzzy model are estimated by the recursive least squared algorithm.The convergence perfromance of the proposed identification algorithm is given by using lemmas and martingale theorem.Finally,the simulation example is given to demonstrate the effectiveness of the proposed method.
基金Supported in part by the National Thousand Talents Program of Chinathe National Natural Science Foundation of China(61473054)the Fundamental Research Funds for the Central Universities of China
文摘In this paper a recursive state-space model identification method is proposed for non-uniformly sampled systems in industrial applications. Two cases for measuring all states and only output(s) of such a system are considered for identification. In the case of state measurement, an identification algorithm based on the singular value decomposition(SVD) is developed to estimate the model parameter matrices by using the least-squares fitting. In the case of output measurement only, another identification algorithm is given by combining the SVD approach with a hierarchical identification strategy. An example is used to demonstrate the effectiveness of the proposed identification method.
