About the properties of excitability and transparency in positive systems with point delays

In this paper, the properties of positivity, excitability and transparency are discussed in time-invariant time-delay continuous-time systems subject to constant point delays. The properties might be investigated under simple tests on the parameterizations of the given continuous-time positive system and two associated ones. One of these systems is obtained by discretization of the given system while the other one is parameterized with the use of the influence graph of the original system. A dynamic economic Leontief-type model is discussed according to the presented formalism.