University of Isfahan Transactions on Combinatorics 2251-8657 2 4 2013 12 01 Graph theoretical methods to study controllability and leader selection for dead-time systems 25 36 3616 10.22108/toc.2013.3616 EN Majdeddin Najafi Avionics Research Institute Farid Shaikholeslam Electrical & Computer Engineering Department Journal Article 2013 09 13 In this article a graph theoretical approach is employed to study some specifications of dynamic systems with time delay in the inputs and states‎, ‎such as structural controllability and observability‎. ‎First‎, ‎the zero and non-zero parameters of a proposed system have been determined‎, ‎next the general structure of the system is presented by a graph which is constructed by non-zero parameters‎. ‎The structural controllability and observability of the system is investigated using the corresponding graph‎. ‎Our results are expressed for multi-agents systems with dead-time‎. ‎As an application we find a minimum set of leaders to control a given multi-agent system‎. Graph Methods Dead-time Systems Multi-Agent Systems Structural Controllability https://toc.ui.ac.ir/article_3616_b2a99bce0bfaf49e3d546e59ee0937c0.pdf