Showing papers by "W. M. Wonham published in 2018"
TL;DR: Overall, the trend has been from centralized or ‘monolithic’ control to more structured architectures, and from ‘naive’ to symbolic computation.
65 citations
01 Dec 2018
TL;DR: This tutorial paper deals with the Internal Model Principle (IMP) from different perspectives to enlarge the vision to other fields where “internal models” play a role and presents an “abstract” theory of IMP applicable to a large class of systems.
Abstract: This tutorial paper deals with the Internal Model Principle (IMP) from different perspectives. The goal is to start from the principle as introduced and commonly used in the control theory and then enlarge the vision to other fields where “internal models” play a role. The biology and neuroscience fields are specifically targeted in the paper. The paper ends by presenting an “abstract” theory of IMP applicable to a large class of systems.
33 citations
TL;DR: This study presents a novel modular modeling framework to describe the parameters of tasks, conforming to the pertinent concepts and techniques of discrete-event systems (DES), based on supervisory control theory.
6 citations
TL;DR: In this article, an operator on languages is proposed whose largest fixpoint is the supremal relatively observable sublanguage of a given language, and it is shown that the sequence converges finitely to this sublanguage.
Abstract: Recently we proposed relative observability for supervisory control of discrete-event systems under partial observation. Relative observability is closed under set unions and hence there exists the supremal relatively observable sublanguage of a given language. In this paper we present a new characterization of relative observability, based on which an operator on languages is proposed whose largest fixpoint is the supremal relatively observable sublanguage. Iteratively applying this operator yields a monotone sequence of languages; exploiting the linguistic concept of support based on Nerode equivalence, we prove for regular languages that the sequence converges finitely to the supremal relatively observable sublanguage, and the operator is effectively computable. Moreover, for the purpose of control, we propose a second operator that in the regular case computes the supremal relatively observable and controllable sublanguage.
4 citations
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TL;DR: This work shows that the model of timed discrete-event systems (TDES) proposed by Brandin and Wonham is essentially a synchronous product structure and has its application in developing a more efficient timed state-tree structures (TSTS) framework.
Abstract: In this work, we show that the model of timed discrete-event systems (TDES) proposed by Brandin and Wonham is essentially a synchronous product structure. This resolves an open problem that has remained unaddressed for the past 25 years and has its application in developing a more efficient timed state-tree structures (TSTS) framework. The proof is constructive in the sense that an explicit synchronous production rule is provided to generate a TDES from the activity automaton and the timer automata after a suitable transformation of the model.
2 citations
TL;DR: It is shown that the maximally permissive entrance control functions can be encoded using finite state automata, and for any iteration-closed star language, there exists a template with only global events that realizes it.
1 citations
TL;DR: By relabeling the queue arrival events and service events to the same symbols respectively, the automaton model of a queue will be converted to the structure of a buffer, which is proved to be independent of the total size of the customer population, as long as the queue size is held fixed.
Abstract: The customer population of entities potentially requesting to join a queue for service often have identical structure, ie, the same state set and isomorphic transitions The state size of the automaton modeling a queue will grow rapidly with increase of the size of this population However, by relabeling the queue arrival events and service events to the same symbols respectively, the automaton model of a queue will be converted to the structure of a buffer, which is proved to be independent of the total size of the customer population, as long as the queue size is held fixed We propose the model of a dynamic buffer to embody order and shift of a queue The result is applied to a manufacturing facility with a dynamic buffer to manage the repair of broken down machines
1 citations