From classic observability to a simple fuzzy observability for fuzzy discrete-event systems

In order to determine uncertainties from restricted available information, fuzzy discrete-event systems (FDESs), or fuzzy discrete-event dynamic systems (FDEDSs), were recently proposed. These frameworks include fuzzy states and events occurring simultaneously with different membership degrees. Fuzzy states and events have been used to describe uncertainties that occur often in practical problems, such as treatment planning for HIV/AIDS patients, sensory information processing for robotic control, and fault diagnosis problems. In order to measure information associated with FDESs or FDEDSs, the classical discrete event system (DES) observability has been turned into fuzzy observability for FDESs or FDEDSs. The newly proposed method allows ease of defining degrees of observability so that uncertainties in FDESs or FDEDSs can be dealt with effectively. This gives an opportunity to design better decision-making systems. To calculate the observability degree, a simple fuzzy observability checking method is introduced, and two examples are elaborated upon to illustrate the presented method. Finally, the newly proposed method is tested on a heating, ventilating, and air-conditioning (HVAC) system.


On maximal permissiveness of hierarchical and modular supervisory control approaches for discrete event systems
Schmidt, Klaus Verner (2008-08-26)
Recently, several efficient modular and hierarchical approaches for the control of discrete event systems (DES) have been proposed. Although these methods are very suitable for dealing with the state space explosion problem, their common limitation is that either maximal permissiveness is not addressed or unnecessarily restrictive conditions are required in order to ensure maximally permissive control. In this paper we develop a unified framework for the investigation of maximal permissiveness of modular co...
Multi-objective decision making using fuzzy discrete event systems: A mobile robot example
Boutalis, Yiannis; Schmidt, Klaus Verner (2010-09-29)
In this paper, we propose an approach for the multi-objective control of sampled data systems that can be modeled as fuzzy discrete event systems (FDES). In our work, the choice of a fuzzy system representation is justified by the assumption of a controller realization that depends on various potentially imprecise sensor measurements. Our approach consists of three basic steps that are performed in each sampling instant. First, the current fuzzy state of the system is determined by a sensor evaluation. Seco...
Nonblocking hierarchical control of decentralized des
Schmidt, Klaus Verner; Moor, Thomas (null; 2005-12-01)
This work considers a hierarchical control architecture for a class of discrete event systems which can also be applied to decentralized control systems. It is shown that nonblocking supervisory control on the high level of the hierarchy results in nonblocking and hierarchically consistent control on the low level. Copyright © 2005 IFAC.
Efficient Abstractions for the Supervisory Control of Modular Discrete Event Systems
Schmidt, Klaus Verner (2012-12-01)
The topic of this technical note is the nonblocking and maximally permissive abstraction-based supervisory control for modular discrete event systems (DES). It is shown, that an efficient abstraction technique, that was developed for the nonconflict verification of modular DES, is also suitable for the nonblocking supervisory control. Moreover, it is proved that this abstraction technique can be extended by the condition of local control consistency, in order to achieve maximally permissive supervision. Dif...
Mobile robot navigation based on fuzzy discrete event systems
Tampakis, Georgios; Schmidt, Klaus Verner; Boutalis, Yiannis (2009-12-01)
Recently, several approaches for the control of fuzzy discrete event systems (FDES) have been proposed. First results towards the use of FDES in mobile robot navigation have also been presented, which however mainly build on sensory information processing. In this paper, we develop a methodology to compute control actions for the navigation of a mobile robot based on distributed FDES. The FDES description permits to take into account possible uncertainties in sensory information and enables a prediction of ...
Citation Formats
E. KILIÇ and M. K. Leblebicioğlu, “From classic observability to a simple fuzzy observability for fuzzy discrete-event systems,” INFORMATION SCIENCES, pp. 224–232, 2012, Accessed: 00, 2020. [Online]. Available: