  This article determines and characterizes the minimal number of actuators
needed to ensure structural controllability of a linear system under structural
alterations that can severe the connection between any two states. We assume
that initially the system is structurally controllable with respect to a given
set of controls, and propose an efficient system-synthesis mechanism to find
the minimal number of additional actuators required for resilience of the
system w.r.t such structural changes. The effectiveness of this approach is
demonstrated by using standard IEEE power networks.
