There is a tide in the affairs of men,
Which, taken at the flood, leads on to fortune;
...
On such a full sea are we now afloat;
And we must take the current when it serves,
Or lose our ventures.
Shakespeare: Julius Caesar, IV, iii Research into real-time is ``at the flood'' and we are afloat on a ``full sea'' of models of time, execution models, logics, languages, theories and applications. The critical nature of hardware and software systems operating in a real-time situation makes it imperative that we understand fully the consequences of system malfunction, and that we use the best of these theories, methodologies and tools to deal with the very real technological problems facing us daily. Indeed, dedicated real-time applications form one of the great accomplishments of current computer technology. Real-time applications, however, bring forth new and intriguing problems regarding program specification, verification and development, and these have motivated intensive programs of research over the last decade.
Now, ``we must take the current''. It is time to consider what has been achieved and how to progress from this point.
The AMAST movement, initiated in 1989, and aiming to use algebraic methodology for the development of software technology, has started to show results. These results can now be focussed on real-time system development. To consider the AMAST perspective on real-time systems, a First AMAST Workshop on Real-Time Systems was held in Iowa City, in November 1993. The goal of the Workshop was to:
All the Workshop speakers, leading players in the area, were invited. Seventeen papers were presented, representing some of our best understanding of real-time problems and applications. All the authors were given the opportunity to refine the text of their papers as a result of the lively discussions that took place during the Workshop. A tangible product of this procedure is the present volume. It is more than simply a proceedings, if only for the fact that there was much more collaborative effort involved in the preparation of the final chapters of this book than normal for a usual proceedings. A series of further workshops on real-time systems is planned and it is hoped that these will lead to a Handbook on Real-Time System Development in the AMAST Series in Computing.
Without a doubt, this Workshop was a scientific and social success. For this, we thank the speakers, and other participants, for the high quality of presentations and discussions. This high quality has now been translated onto the pages of this book. The organizers are very grateful for the generosity of the sponsoring bodies: Office of Naval Research, National Science Foundation, ESPRIT Basic Research Programs, the University of Iowa, and the University of Twente. However, the main catalyst in the organization team is Teodor Rus whose enthusiasm, expertise, and hard work provided the energy for the rest of us. Teo Rus carried the brunt of the organization and has done most of the work needed in getting this book to its final state.
Charles Rattray