  A closed-loop control of a reaction-diffusion type process is introduced. The
control system consist of a finite number of control and measurement devices.
The measurement devices collect information about the current state of the
process. The control devices influence the process, responding to data obtained
from the measurement devices. Each control device takes into account the data
from all measurement devices. The rule of accounting the data from measurement
devices by a single control device involves defining suitable weights for each
pair of one control device and one measurement device. A weight reflects how
important is a given measurement device to a given control device. The aim of
this control system is to bring the process possibly close to a user defined
reference state or trajectory.
  We are interested in a situation where the user can adjust the control system
by choice of the control and measurement devices and the weights. For this
reason, one of the aims of the preset work is to study the behavior under
perturbations of these elements for the mathematical model realizing the above
control concept. Moreover, we formulate and justify results concerning
existence and uniqueness of solutions of the investigated model. Finally,
numerical prototypes illustrating properties of the model are presented.
