ω-automaton

About: ω-automaton is a research topic. Over the lifetime, 2299 publications have been published within this topic receiving 68468 citations. The topic is also known as: stream automaton & ω-automata.

State structures for verification and real-time control of hybrid automata

Abstract: We show that the coarsest information structure needed to model a plant (environment) for verification of safety expressed as the avoidance of unsafe states is too coarse for the synthesis of control. The information structure is formulated as a partition of /spl Rfr//sub +//sup n/, which represents the state set of the continuous component of a timed automaton, a special case of a linear hybrid automaton. A feedback controller reads the discrete (a location) and continuous (a point in /spl Rfr//sub +//sup n/) information and produces an actuation by delaying or forcing the occurrence of certain transitions in the plant to ensure that dangerous states would not be reached. Finer information in the form of temporal successors is crucial for control but is not needed for verification. The challenge of finding the coarsest information structure for optimal control is proposed.

Approximate completed trace equivalence of real-time linear algebraic Hybrid Automata

Abstract: In allusion to design simpler software system, the paper proposes approximate completed trace equivalence of real-time linear algebraic Hybrid Automata. Firstly, it pulls real-time linear algebraic program into Hybrid Automaton and establishes real-time linear algebraic Hybrid Automaton. Next, it uses matrix Frobenius norm to analyse approximation of real-time linear algebraic Hybrid Automata. Afterwards, it gets approximate completed trace equivalence of real-time linear algebraic Hybrid Automata. Finally, the Email virus spreading automata example shows that approximate completed trace equivalence of real-time algebraic Hybrid Automata can simplify automaton.

Groups and Semigroups Defined by Colorings of

Abstract: In this paper we combine the algebraic properties of Mealy machines generating self-similar groups and the combinatorial properties of the corresponding deterministic finite automata (DFA). In particular, we relate bounded automata to finitely generated synchronizing automata and characterize finite automata groups in terms of nilpotency of the corresponding DFA. Moreover, we present a decidable sufficient condition to have free semigroups in an automaton group.A series of examples and applications is widely discussed, in particular we show a way to color the De Bruijn automata into Mealy automata whose associated semigroups are free, and we present some structural results related to the associated groups.

Improved Preprocessing Methods for Modulo Scheduling Algorithms

Abstract: Instruction scheduling with an automaton-based resource conflict model is well-established for normal scheduling. Such models have been generalized to software pipelining in the modulo-scheduling framework. One weakness with existing methods is that a distinct automaton must be constructed for each combination of a reservation table and initiation interval. In this work, we present a different approach to model conflicts. We construct one automaton for each reservation table which acts as a compact encoding of all the conflict automata for this table, which can be recovered for use in modulo-scheduling. The basic premise of the construction is to move away from the Proebsting-Fraser model of conflict automaton to the Muller model of automaton modelling issue sequences. The latter turns out to be useful and efficient in this situation. Having constructed this automaton, we show how to improve the estimate of resource constrained initiation interval. Such a bound is always better than the average-use estimate. We show that our bound is safe: it is always lower than the true initiation interval. This use of the automaton is orthogonal to its use in modulo-scheduling. Once we generate the required information during pre-processing, we can compute the lower bound for a program without any further reference to the automaton.