The concept of fuzzy reasoning has been extended to Petri nets and has been applied for modeling of discrete event systems [1]. However, the theory was not extended to supervisory control of discrete event systems because there is no valid translation for fuzzy Petri nets into ladder logic diagrams. Discrete event systems are time and event dependent and hence digital in nature. However, discre...

Event detection is a central component in numerous wireless sensor network (WSN) applications. In spite of this, the area of event description has not received enough attention. The majority of current event description approaches rely on using precise values to specify event thresholds. However, we believe that crisp values cannot adequately handle the often imprecise sensor readings. In this ...

Knowledge systems are characterized by being active, uncertain and adaptive in pervasive computing environments, and Fuzzy Event-Condition-Action (ECA) rules can effectively describe these features of knowledge systems. To analyze the static structure and dynamic behavior of fuzzy ECA rules, a fuzzy colored time Petri net model (FCTPN) is proposed. The FCTPN is able to model the fuzzy ECA rules...

In previous studies we first concentrated on utilizing crisp simulationto produce discrete event fuzzy systems simulations. Then we extendedthis research to the simulation of continuous fuzzy systems models. In this paperwe continue our study of continuous fuzzy systems using crisp continuoussimulation. Consider a crisp continuous system whose evolution depends ondifferential equations. Such a ...

We present a method for inducing a set of rules from time series data, which is originated from a monitored process. The proposed method is called MAPS (Mining Aberrant Patterns in Sequences) and it may be used in decision support or in control to identify faulty system states. It consists of four parts: training, identification, event mining and prediction. In order to improve the flexibility ...

fault tree analysis (fta) as a probabilistic risk assessment (pra) method is used to identify basic causes leading to an undesired event, to represent logical relation of these basic causes in leading to the event, and finally to calculate the probability of occurrence of this event. to conduct a quantitative fta, one needs a fault tree along with failure data of the basic events (bes). someti...

There are various types of uncertainty in the real world. This is a motivation to investigate the behavior of uncertain phenomena. Random phenomena is one class of objective uncertain phenomena which has been well studied. Probability theory is an efficient tool to study the behavior of random phenomena. Besides randomness, fuzziness is a basic type of subjective uncertainty initiated by Zadeh....

In economic practice, we often deal with events that are defined only vaguely. Such indeterminate events can be modelled by fuzzy sets. In the paper, we examine two main ways of expressing a probability of fuzzy events that are proposed in the literature. We study their mathematical properties and discuss their interpretation. We conclude that none of the approaches gives an appropriate probabi...

Probabilistic safety assessment (PSA) which plays a crucial role in risk evaluation is a quantitative approach intended to demonstrate how a nuclear reactor meets the safety margins as part of the licensing process. Despite PSA merits, some shortcomings associated with the final results exist. Conventional PSA uses crisp values to represent the failure probabilities of basic events. This causes...