Abstract: Stability analysis and stabilization synthesis problems of the singularly perturbed switched systems (SPSSs) are investigated in this paper. First, stability of the SPSS with stable subsystems is discussed by using an average dwell time approach with a full-order piecewise Lyapunov function. Then, the result is extended to the situation that not all the subsystems are Hurwitz stable. ...

In 1826 N. Abel found a generalization of the binomial formula. In 1902 Abel’s theorem was further generalized by A. Hurwitz. In this paper we describe constructions that provide infinitely many identities each being a generalization of a Hurwitz’s identity. Moreover, we give combinatorial interpretations of all these identities as the forest volumes of certain directed graphs. Published by Els...

An extension of Kato’s stability condition for nonautonomous Cauchy problems is presented. It is proved that in the commutative case this condition and a mild regularity assumption imply wellposedness. If one supposes the Kato-stability, then the solutions are given by an integral formula. By means of examples we show that in general these stability conditions cannot be omitted in our results. ...

The aim of this paper is to give sufficient conditions for a switched linear system defined by a pair of Hurwitz matrices that share a common but not strict quadratic Lyapunov function to be GUAS. We show that this property is equivalent to the uniform observability on [0,+∞) of a bilinear system defined on a subspace whose dimension is in most cases much smaller than the dimension of the switc...

Necessary and sufficient conditions for the bi-variate characteristic polynomial of a matrix to be very strict Hurwitz (VSHP) are presented. These conditions are based on solving the Lyapunov equation for 2 0 continuous systems using the Kronecker product and lead to a simple test for the VSHP property. It requires testing only the eigenvalues of three stable matrices and this is simpler than t...

A new condition for a polynomial ( ) to be a local convex direction for a Hurwitz stable polynomial ( ) is derived. The condition is in terms of polynomials associated with the even and odd parts of ( ) and ( ), and constitutes a generalization of Rantzer’s phase-growth condition for global convex directions. It is used to determine convex directions for certain subsets of Hurwitz stable polyno...

In the paper we propose a new synchronization principle. To guarantee synchronization between coupled chaotic oscillators, proper coupling constants are selected by the Liapunov stability theory and Hurwitz Theorem. As an example and application, we prove the conjecture [Wu & Chua, 1994] that synchronization between two chaotic Chua’s circuits can be achieved by using the second state as feedba...

1.1. Log-K-stability Let (X, J) be a Fano manifold, that is, K−1 X is ample. A basic problem in Kähler geometry is to determine whether (X, J) has a Kähler–Einstein metric (see [22]). The existence problem of Kähler–Einstein metric is a special case of the existence problem of constant scalar curvature Kähler (cscK) metric. For the latter, we fix an ample line bundle L on (X, J). We have the fo...

Abstract. We establish a series of indefinite integral formulae involving the Hurwitz zeta function and other elementary and special functions related to it, such as the Bernoulli polynomials, ln sin(πq), ln Γ(q) and the polygamma functions. Many of the results are most conveniently formulated in terms of a family of functions Ak(q) := kζ (1 − k, q), k ∈ N, and a family of polygamma functions o...

We calculate the cycle class of the Hurwitz divisor D2 on Mg for g = 2k given by the degree k+1 covers of P with simple ramification points, two of which lie in the same fibre. We also study some aspects of the geometry of the natural map from the Hurwitz space H2k,k+1 to the moduli space M2k .