Queen’s Discrete-Event Systems Lab

We work on discrete-event systems (DES). We are interested in processes whose behaviour is described by sequences of events or actions and which often require some form of control to induce desirable behaviour. Work in this area focuses on mathematically modeling such systems and on searching for solutions to control problems. Some of the areas of application are in cyber-physical systems, computer systems, manufacturing plants, telecommunication networks and robotics. The mathematical tools used include formal languages and automata theory, mathematical logic, and graph theory.

Some of our interests and recent joint projects include the following:

  • control of a discrete-event system in the face of an attack where an attacker inserts or removes some event occurrences
  • enforcing opacity in systems, namely ensuring that secrets remain secret
  • using epistemic logic to model system behaviour and guide actions and decision-making in systems
  • formal mathematical models and software tools for emergency response to large-scale disasters or crises such as health epidemics
  • control and communication protocols for decentralized discrete-event problems where agents with only partial observations (due to limited sensor access) communicate in order to gain information
  • mathematical models of telecommunication problems so that discrete-event control theory can aid in protocol verification or can lead to protocol synthesis
  • application of discrete-event control theory to determine where concurrency control should be inserted into software programs

In general, we are interested in connecting discrete-event systems theory with other distributed-system problems that may arise in computer systems, in economic systems, and in telecommunication systems.  We are also very interested in understanding, modeling, and preventing attacks on cyber-physical systems.

Our research is funded, in great part, by the Natural Sciences and Engineering Research Council of Canada (NSERC).