Equivalence, invariance and dynamical system canonical modelling. II. Invariant properties of reachable models and associated transformations
Equivalence, invariance and dynamical system canonical modelling. I. Invariant properties of observable models and associated transformations
Externally and internally positive singular discrete-time linear systems
Notions of externally and internally positive singular discrete-time linear systems are introduced. It is shown that a singular discrete-time linear system is externally positive if and only if its impulse response matrix is non-negative. Sufficient conditions are established under which a single-output singular discrete-time system with matrices in canonical forms is internally positive. It is shown that if a singular system is weakly positive (all matrices E, A, B, C are non-negative), then it...