  This paper presents a performance-regulation method for a class of stochastic
timed event-driven systems aimed at output tracking of a given reference
setpoint. The systems are either Discrete Event Dynamic Systems (DEDS) such as
queueing networks or Petri nets, or Hybrid Systems (HS) with time-driven
dynamics and event-driven dynamics, like fluid queues and hybrid Petri nets.
The regulator, designed for simplicity and speed of computation, is comprised
of a single integrator having a variable gain to ensure effective tracking
under time-varying plants. The gain's computation is based on the Infinitesimal
Perturbation Analysis (IPA) gradient of the plant function with respect to the
control variable, and the resultant tracking can be quite robust with respect
to modeling inaccuracies and gradient-estimation errors. The proposed technique
is tested on examples taken from various application areas and modeled with
different formalisms, including queueing models, Petri-net model of a
production-inventory control system, and a stochastic DEDS model of a multicore
chip control. Simulation results are presented in support of the proposed
approach.
