Necessary and sufficient conditions for output reachability and null output controllability of positive linear discrete systems with delays in state, input, and output are established. It is also shown that output reachability and null output controllability together imply output controllability.
"On the Output Controllability of Positive Discrete Linear Delay Systems." Abstr. Appl. Anal. 2017 1 - 12, 2017. https://doi.org/10.1155/2017/3651271