The problem of counteracting the effects of adversarial inputs on the operation of an asynchronous sequential machine is considered. The objective is to build an automatic state-feedback controller that returns an asynchronous sequential machine to its original state, after the machine has undergone a state transition caused by an adversarial input. It is shown that the existence of such a cont...

In hardware and software design model checkers are nowadays used with success to verify properties of system components [23]. The limits of the approach to cope with the size and the complexity of modern computer-based systems are felt when it comes to provide evidence of the trustworthiness of the entire system that has been built out of verified components. To achieve this task one has to exp...

We introduce the concept of an algebraic state machine. This is a state transition machine all parts of that are described by algebraic and logical means. This way we base the description of state transition systems exclusively on the concept of algebraic specifications. Also the state of an algebraic state machine is represented by an algebra. In particular, we describe the state spaces of the...

One approach to formally specifying a system is to use a form of extended finite-state machine called a stream X-machine. A stream X-machine is a type of X-machine that describes a system as a finite set of states, each with an internal store, called memory, and a number of transitions between the states. A stream X-machine may be modelled by a finite automaton (the associated finite automaton)...

Hierarchical Petri nets beside UML state machine diagrams, sequentional function charts (SFC) and hierarchical concurrent state machines are common solution for specification of logic controllers. These specification formats provide both concurrency and modeling on multi levels of abstraction (hierarchic approach). But only state machine diagrams supports exceptions handling in direct way. Prog...