  In this technical report we summarise the spatio-temporal features and
present the core operators of FocusST specification framework. We present the
general idea of these operators, using a Steam Boiler System example to
illustrate how the specification framework can be applied.
  FocusST was inspired by Focus, a framework for formal specification and
development of interactive systems. In contrast to Focus, FocusST is devoted to
specify and to analyse spatial (S) and timing (T) aspects of the systems, which
is also reflected in the name of the framework: the extension ST highlights the
spatio-temporal nature of the specifications.
