The control of discrete event systems
Article Abstract:
Discrete event systems (DESs) are dynamic systems that change at the sudden occurrence of physical events at what may be unknown intervals. DESs are common in manufacturing, robotics, logistics and other such environments that require control and coordination to assure an orderly flow of events. Automata and formal language models for DESs are examined, and a theory developed earlier is extended here in an attempt to analyze controllability, observability, aggregation, decentralized and hierarchical control, and other such control theoretic ideas for DESs from a qualitative perspective. The model used separates the idea of open loop dynamics (plant) from the feedback control, which allows several control synthesis problems to be formulated and solved. Not all the features that a full theory of DESs should support are supported, but it serves very well for demonstrating underlying DES concepts.
Publication Name: Proceedings of the IEEE
Subject: Electronics
ISSN: 0018-9219
Year: 1989
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Algebras of discrete event models
Article Abstract:
New classes of models for systems made up of interacting modules of discrete events, such as manufacturing systems and communication networks, as well as for continuous variable systems managed by controllers that act when triggered by certain discrete events are needed by system designers. Such discrete event models (DEMs) are developed that describe logical system behavior, an example being mathematical models representing the set of traces or sequences of events that the system can execute. State machines, Petri nets, and Hoare's communicating sequential processes are examples of DEM formalisms. All such formalisms are algebras, that is, a set of models together with operators that combine models to create other models in ways that interconnect real systems. A general approach for building model algebras is presented that covers deterministic and nondeterministic models.
Publication Name: Proceedings of the IEEE
Subject: Electronics
ISSN: 0018-9219
Year: 1989
User Contributions:
Comment about this article or add new information about this topic: