An object-oriented algebraic steam-boiler control specification

Abstract

In this paper an object-oriented algebraic solution of the steam-boiler specification problem is presented. The solution is written in Timed Maude. Timed Maude is a specification language under development where the static parts of the specified system are described by equational specifications, whereas the behaviour of a process is described by timed term rewriting. Timed Maude is based on Meseguer's Maude language, and its underlying logic is timed rewriting logic, an extension of rewriting logic to deal with hard real-time systems.

The specification focuses on the description of the control program, which is designed as the parallel composition of several objects which communicate using messages. The transmission of such internal messages is assumed to be instantaneous whereas the communication with the environment can be time consuming.

To validate the specification it is shown that only finitely many zero-time transitions are possible in a row implying that Zeno computations cannot happen.

Work completed while on leave at LMU München.