Karen Rudie

Bio: Karen Rudie is an academic researcher from Queen's University. The author has contributed to research in topics: Supervisory control & Supervisor. The author has an hindex of 22, co-authored 82 publications receiving 2315 citations. Previous affiliations of Karen Rudie include University of Toronto & University of Minnesota.

Think globally, act locally: decentralized supervisory control

Abstract: Decentralized supervisory control is investigated by considering problem formulations that model systems whose specifications are given as global constraints, but whose solution is described by local controllers. A necessary and sufficient condition is given for the existence of a solution to the problem of finding decentralized supervisors that ensure that the behavior of the closed-loop system lies in a given range. Where the range of behavior can be described by regular languages, it can be effectively tested whether the decentralized control problem is solvable; in this case, a procedure is given to compute the associated supervisors. >

Think Globally, Act Locally: Decentralized Supervisory Control

Abstract: Decentralized supervisory control is investigated by considering problem formulations that model systems whose specifications are given as global constraints but whose solution is described by local controllers. A necessary and sufficient condition is given for the existence of a solution to the problem of finding decentralized supervisors that ensure that the behaviour of the closed-loop system lies in a given range. Where the range of behaviour can be described by regular languages, it can be effectively tested whether the decentralized control problem is solvable; in this case, a procedure is given to compute the associated supervisors.

The computational complexity of decentralized discrete-event control problems

Abstract: Computational complexity results are obtained for decentralized discrete-event control problems. These results generalize the earlier work of Tsitsiklis (1989), who showed that for a special class of centralized supervisory control problems under partial observation, there is an algorithm for determining in polynomial time whether or not a solution exists. The negative complexity results associated with Tsitsiklis work also carry over to the decentralized case, so that solution existence for the more general class is not decidable in polynomial time, nor does there exist a polynomial-time algorithm for producing supervisor solutions when such solutions exist. >

Minimal communication in a distributed discrete-event system

Abstract: This paper deals with distributed discrete-event systems, in which agents (or local sites) are required to communicate in order to perform some specified tasks. Associated with each agent is a finite-state automaton that captures the required tasks to be performed at that site. The problem considered is that each agent must be able to distinguish between the states of its automaton. To help it disambiguate states, an agent uses a combination of direct observation (obtained from sensor readings available to that agent) and communicated information (obtained from sensor readings available to another agent). Since communication may be costly, a strategy to minimize communication between sites is developed. The complexity of the solution reflects the interdependence of the agents' communication protocols. That is, the decision to communicate the occurrence of an event relies on which event sequences are indistinguishable to an agent, which, in turn, is a result of what has already been communicated to that agent.

For the Grid and Through the Grid: The Role of Power Line Communications in the Smart Grid

Abstract: Are Power Line Communications (PLC) a good candidate for Smart Grid applications? The objective of this paper is to address this important question. To do so, we provide an overview of what PLC can deliver today by surveying its history and describing the most recent technological advances in the area. We then address Smart Grid applications as instances of sensor networking and network control problems and discuss the main conclusions one can draw from the literature on these subjects. The application scenario of PLC within the Smart Grid is then analyzed in detail. Because a necessary ingredient of network planning is modeling, we also discuss two aspects of engineering modeling that relate to our question. The first aspect is modeling the PLC channel through fading models. The second aspect we review is the Smart Grid control and traffic modeling problem which allows us to achieve a better understanding of the communications requirements. Finally, this paper reports recent studies on the electrical and topological properties of a sample power distribution network. Power grid topological studies are very important for PLC networking as the power grid is not only the information source but also the information delivery system-a unique feature when PLC is used for the Smart Grid.