98%
921
2 minutes
20
This paper considers the problem of non-parametric identification of low-order models from time-domain experimental data using a combination of Caratheodory Fejer and Loewner-based interpolation, followed by a Loewner matrix Balanced Reduction (LBR) step. As we show in the paper, the Loewner matrix is an estimator for the trace norm of a system, playing a role similar to the one played by the Hankel matrix. However, utilizing Zolotarev numbers to establish decay rate bounds for singular values reveals that the decay of singular values in the Loewner matrix is considerably faster than that in the Hankel matrix. Thus, Loewner-based methods yield lower order systems, with the same error bound, than comparable ones based on Hankel matrices. The effectiveness of our method is demonstrated through a numerical example.
Download full-text PDF |
Source |
---|---|
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC12360321 | PMC |
http://dx.doi.org/10.1016/j.ifacol.2024.08.528 | DOI Listing |
IFAC Pap OnLine
September 2024
ECE Dept., Northeastern University, Boston, MA 02115 USA.
This paper considers the problem of non-parametric identification of low-order models from time-domain experimental data using a combination of Caratheodory Fejer and Loewner-based interpolation, followed by a Loewner matrix Balanced Reduction (LBR) step. As we show in the paper, the Loewner matrix is an estimator for the trace norm of a system, playing a role similar to the one played by the Hankel matrix. However, utilizing Zolotarev numbers to establish decay rate bounds for singular values reveals that the decay of singular values in the Loewner matrix is considerably faster than that in the Hankel matrix.
View Article and Find Full Text PDFFor accurate circuit-level simulations, passive photonic integrated circuits (PICs) must be modeled in the time domain, using their frequency responses. The complex vector fitting (CVF) method has been established as a reliable technique for constructing time-domain state-space models of passive PICs. This paper introduces a more advanced method, called the baseband Loewner matrix approach, which offers enhanced efficiency compared to CVF.
View Article and Find Full Text PDFMath Biosci Eng
January 2021
School of Mechatronic Engineering and Automation, Shanghai University, Shanghai 200444, China.
In this paper we propose a data driven realization and model order reduction (MOR) for linear fractional-order system (FoS) by applying the Loewner-matrix method. Given the interpolation data which obtained by sampling the transfer function of a FoS, the minimal fractional-order state space descriptor model that matching the interpolation data is constructed with low computational cost. Based on the framework, the commensurate order α of the fractional-order system is estimated by solving a least squares optimization in terms of sample data in case of unknown order-α.
View Article and Find Full Text PDFAnal Math Phys
May 2020
Department of Mathematics, Saarland University, 66123 Saarbrücken, Germany.
First we introduce the two tau-functions which appeared either as the -function of the integrable hierarchy governing the Riemann mapping of Jordan curves or in conformal field theory and the universal Grassmannian. Then we discuss various aspects of their interrelation. Subsequently, we establish a novel connection between free probability, growth models and integrable systems, in particular for second order freeness, and summarise it in a dictionary.
View Article and Find Full Text PDFPhys Rev Lett
July 2006
School of Mathematics, University of Bristol, Bristol BS8 1TW, United Kingdom.
We develop a percolation model for nodal domains in the eigenvectors of quantum chaotic torus maps. Our model follows directly from the assumption that the quantum maps are described by random matrix theory. Its accuracy in predicting statistical properties of the nodal domains is demonstrated for perturbed cat maps and supports the use of percolation theory to describe the wave functions of general Hamiltonian systems.
View Article and Find Full Text PDF