All a b c d e f g h i j k l m n o p q r s t u v w x y z Other

Previous Page 2 Next

Displaying 21 – 40 of 41

Showing per page

Exact controllability of linear dynamical systems: A geometrical approach

María Isabel García-Planas (2017)

Applications of Mathematics

In recent years there has been growing interest in the descriptive analysis of complex systems, permeating many aspects of daily life, obtaining considerable advances in the description of their structural and dynamical properties. However, much less effort has been devoted to studying the controllability of the dynamics taking place on them. Concretely, for complex systems it is of interest to study the exact controllability; this measure is defined as the minimum set of controls that are needed...

Existence of pole-zero structures in a rational matrix equation arising in a decentralized stabilization of expanding systems

Dibyendu Baksi, Kanti B. Datta, Goshaidas Ray (2002)

Kybernetika

A necessary and sufficient condition for the existence of pole and zero structures in a proper rational matrix equation T 2 X = T 1 is developed. This condition provides a new interpretation of sufficient conditions which ensure decentralized stabilizability of an expanded system. A numerical example illustrate the theoretical results.

Falseness of the finiteness property of the spectral subradius

Adam Czornik, Piotr Jurgas (2007)

International Journal of Applied Mathematics and Computer Science

We prove that there exist infinitely may values of the real parameter α for which the exact value of the spectral subradius of the set of two matrices (one matrix with ones above and on the diagonal and zeros elsewhere, and one matrix with α below and on the diagonal and zeros elsewhere, both matrices having two rows and two columns) cannot be calculated in a finite number of steps. Our proof uses only elementary facts from the theory of formal languages and from linear algebra, but it is not constructive...

Fixed poles of H 2 optimal control by measurement feedback

Jean-François Camart, Basilio del-Muro-Cuéllar, Michel Malabre (2002)

Kybernetika

This paper is concerned with the flexibility in the closed loop pole location when solving the H 2 optimal control problem (also called the H 2 optimal disturbance attenuation problem) by proper measurement feedback. It is shown that there exists a precise and unique set of poles which is present in the closed loop system obtained by any measurement feedback solution of the H 2 optimal control problem. These “ H 2 optimal fixed poles” are characterized in geometric as well as structural terms. A procedure...

Inequality-based approximation of matrix eigenvectors

András Kocsor, József Dombi, Imre Bálint (2002)

International Journal of Applied Mathematics and Computer Science

A novel procedure is given here for constructing non-negative functions with zero-valued global minima coinciding with eigenvectors of a general real matrix A. Some of these functions are distinct because all their local minima are also global, offering a new way of determining eigenpairs by local optimization. Apart from describing the framework of the method, the error bounds given separately for the approximation of eigenvectors and eigenvalues provide a deeper insight into the fundamentally...

Observability properties of a semi-discrete 1d wave equation derived from a mixed finite element method on nonuniform meshes

Sylvain Ervedoza (2010)

ESAIM: Control, Optimisation and Calculus of Variations

The goal of this article is to analyze the observability properties for a space semi-discrete approximation scheme derived from a mixed finite element method of the 1d wave equation on nonuniform meshes. More precisely, we prove that observability properties hold uniformly with respect to the mesh-size under some assumptions, which, roughly, measures the lack of uniformity of the meshes, thus extending the work [Castro and Micu, Numer. Math.102 (2006) 413–462] to nonuniform meshes. Our results...

Optimal Proliferation Rate in a Cell Division Model

P. Michel (2010)

Mathematical Modelling of Natural Phenomena

We consider a size structured cell population model where a mother cell gives birth to two daughter cells. We know that the asymptotic behavior of the density of cells is given by the solution to an eigenproblem. The eigenvector gives the asymptotic shape and the eigenvalue gives the exponential growth rate and so the Maltusian parameter. The Maltusian parameter depends on the division rule for the mother cell, i.e., symmetric (the two daughter cells have the same size) or asymmetric. We use a...

Parametric control to quasi-linear systems based on dynamic compensator and multi-objective optimization

Da-Ke Gu, Da-Wei Zhang (2020)

Kybernetika

This paper considers a parametric approach for quasi-linear systems by using dynamic compensator and multi-objective optimization. Based on the solutions of generalized Sylvester equations, we establish the more general parametric forms of dynamic compensator and the left and right closed-loop eigenvector matrices, and give two groups of arbitrary parameters. By using the parametric approach, the closed-loop system is converted into a linear constant one with a desired eigenstructure. Meanwhile,...

Poles and zeroes of nonlinear control systems

Jean-François Pommaret (2002)

Kybernetika

During the last ten years, the concepts of “poles” and “zeros” for linear control systems have been revisited by using modern commutative algebra and module theory as a powerful substitute for the theory of polynomial matrices. Very recently, these concepts have been extended to multidimensional linear control systems with constant coefficients. Our purpose is to use the methods of “algebraic analysis” in order to extend these concepts to the variable coefficients case and, as a byproduct, to the...

Robust PI-D controller design for descriptor systems using regional pole placement and/or H 2 performance

Vojtech Veselý, Ladislav Körösi (2020)

Kybernetika

The paper deals with the problem of obtaining a robust PI-D controller design procedure for linear time invariant descriptor uncertain polytopic systems using the regional pole placement and/or H 2 criterion approach in the form of a quadratic cost function with the state, derivative state and plant input (QSR). In the frame of Lyapunov Linear Matrix Inequality (LMI) regional pole placement approach and/or H 2 quadratic cost function based on Bellman-Lyapunov equation, the designed novel design procedure...

Stability Analysis of Cell Dynamics in Leukemia

H. Özbay, C. Bonnet, H. Benjelloun, J. Clairambault (2012)

Mathematical Modelling of Natural Phenomena

In order to better understand the dynamics of acute leukemia, and in particular to find theoretical conditions for the efficient delivery of drugs in acute myeloblastic leukemia, we investigate stability of a system modeling its cell dynamics. The overall system is a cascade connection of sub-systems consisting of distributed delays and static nonlinear feedbacks. Earlier results on local asymptotic stability are improved by the analysis of the linearized...

Currently displaying 21 – 40 of 41