This paper deals with left invertibility problem of implicit hyperbolic systems with delays in infinite dimensional Hilbert spaces. From a decomposition procedure, invertibility for this class of systems is shown to be equivalent to the left invertibility of a subsystem without delays.

In this paper we address the invertibility of invisible watermarking schemes for resolving rightful ownerships, and present attacks which can cause confusion to rightful claims. We shall show that non-invertibility is a necessary but not sufficient condition in resolving ownership disputes. We then define quasi-invertible watermarking schemes, and, present analysis that links invertibility and ...

In this paper the theory of invertibility of matrices of field elements (see e.g. [5], [6]) is developed. The main purpose of this article is to prove that the left invertibility and the right invertibility are equivalent for a matrix of field elements. To prove this, we introduced a special transformation of matrix to some canonical forms. Other concepts as zero vector and base vectors of fiel...

In this paper we consider a class of Discrete-Event Dynamic Systems (DEDS) modeled as finite-state automata in which only some of the transition events are directly observed. An invertible DEDS is one for which it is possible to reconstruct the entire event string from the observation of the output string. The dynamics of invertibility are somewhat complex, as ambiguities in unobservable events...

The paper deals with the generalized Drazin invertibility of combinations of idempotents p, q in a Banach algebra. It proves the equivalence of the generalized Drazin invertibility of p−q and p+q, as well as the equivalence of the generalized Drazin invertibility of the commutator pq − qp and anticommutator pq + qp of p, q. It extends several results of J. Math. Anal. Appl. 359 (2009) 731–738, ...