Observability and Decentralized Control of Fuzzy Discrete Event Systems

Fuzzy discrete event systems as a generalization of (crisp) discrete event systems have been introduced in order that it is possible to effectively represent uncertainty, imprecision, and vagueness arising from the dynamic of systems. A fuzzy discrete event system has been modelled by a fuzzy automaton; its behavior is described in terms of the fuzzy language generated by the automaton. In this paper, we are concerned with the supervisory control problem for fuzzy discrete event systems with partial observation. Observability, normality, and co-observability of crisp languages are extended to fuzzy languages. It is shown that the observability, together with controllability, of the desired fuzzy language is a necessary and sufficient condition for the existence of a partially observable fuzzy supervisor. When a decentralized solution is desired, it is proved that there exist local fuzzy supervisors if and only if the fuzzy language to be synthesized is controllable and co-observable. Moreover, the infimal controllable and observable fuzzy superlanguage, and the supremal controllable and normal fuzzy sublanguage are also discussed. Simple examples are provided to illustrate the theoretical development.Comment: 14 pages, 1 figure. to be published in the IEEE Transactions on Fuzzy System

Natural Language Communication With Virtual Actor

The development of realistic virtual actors in many applications, from user interface to computer entertainment, creates expectations on the intelligence of these actors including their ability to understand natural language. Based on our research in that area over the past years, we highlight specific technical aspects in the development of language-enabled actors. The embodied nature of virtual agents lead to specific syntactic constructs that are not unlike sublanguages: these can be used to specify the parsing component of a natural language interface. However, the most specific aspects of interacting with virtual actors consist in mapping the semantic content of users’ input to the mechanisms that support agents’ behaviours. We suggest that a generalisation of speech acts can provide principles for this integration. Both aspects are illustrated by results obtained during the development of research prototypes.

Fields and Fusions: Hrushovski constructions and their definable groups

An overview is given of the various expansions of fields and fusions of strongly minimal sets obtained by means of Hrushovski's amalgamation method, as well as a characterization of the groups definable in these structures

Governance and Business Communication

The author starts exploring the field by investigating the corporate websites and blogs of the leading US companies - the paper explores the language of the corporate governance, leadership, internal and external specifics of the corporate communication. The paper argues that all companies can be classified into 4 discursive types identified by the author on the basis of the four types of social implications in their discursive rhetori