Klaus-Dieter Schewe

Klaus-Dieter Schewe
Software Competence Center Hagenberg, Linz, Austria

Title:  Behavioural Theory and Logic of Distributed Adaptive Systems


A distributed system can be characterised by autonomously acting agents, where each agent executes its own program, uses shared resources and communicates with the others, but otherwise is totally oblivious to the behaviour of the other agents. In a distributed adaptive system agents may change their programs, enter or leave the collection at any time thereby changing the behaviour of the overall system.

The talk presents a behavioural theory of distributed adaptive systems comprising (1) a small set of postulates characterising such systems in a precise way without any reference to a particular language, (2) an abstract machine model together with a plausibility proof that the abstract machines satisfy the
postulates, and (3) a characterisation proof that any system stipulated by the postulates can be step-by-step simulated by an abstract machine. The theory integrates the behavioural theories for unbounded (synchronous) parallel algorithms, asynchronous concurrent systems, and reflective algorithms, respectively. The behavioural theory implies that concurrent reflective Abstract State Machines (crASMs) can be used as a specification and development language for distributed adaptive systems. Based on the simple observation that concurrent ASMs can be mimicked by non-deterministic parallel ASMs the complete one-step logic for non-deterministic ASMs can be exploited for the definition of a logic capturing concurrency. By making the extra-logical rules in the logic subject to being interpreted in a state the logic can be extended to capture also reflection.


  • PhD in Pure Mathematics (1985 University of Bonn), DSc in Theoretical Computer Science (1995 BTU Cottbus)
  • Positions as Associate Professor (1994-1999 TU Clausthal), Full Professor (2000-2010 Massey University) and Scientific Director (2010-2017 Software Competence Center Hagenberg)
  • Main fields of research: rigorous methods, logic and semantics, data and knowledge base theory, distributed and hybrid systems
  • Founder of Foundations of Information and Knowledge Systems (FoIKS)