We continue investigation of languages, accepted by timed automata of Alur and Dill. In [ACM97] timed regular expressions equivalent to timed automata were introduced. Here we introduce quasilinear equations over timed languages with regular coefficients. We prove that the minimal solution of such an equation is regular and give an algorithm to calculate this solution. This result is used to ob...

Reachability analysis for timed automata using SAT-based methods was considered in many papers, occurring to be a very efficient model checking technique. In this paper we show how to apply this method of verification to timed automata with discrete data, i.e., to standard timed automata augmented with integer variables. The theoretical description is supported by some preliminary experimental ...

Timed automata can be studied in not only a dense-time setting but also a discrete-time setting. The most common example of discrete-time semantics is the so called sampled semantics (i.e., discrete semantics with a xed time granularity "). In the real-time setting, the universality problem is known to be undecidable for timed automata. In this work, we study the universality question for the l...

We consider the fundamental problem of Büchi acceptance in timed automata in a robust setting. The problem is formalised in terms of controller synthesis: timed automata are equipped with a parametrised game-based semantics that models the possible perturbations of the decisions taken by the controller. We characterise timed automata that are robustly controllable for some parameter, with a sim...

Priced timed automata provide a natural model for quantitative analysis of real-time systems and have been successfully applied in various scheduling and planning problems. The optimal reachability problem for linearly-priced timed automata is known to be PSPACE-complete. In this paper we investigate priced timed automata with more general prices and show that in the most general setting the op...

Probabilistic timed automata are an extension of timed automata with discrete probability distributions, and can be used to model timed randomized protocols or fault-tolerant systems. We present symbolic model checking algorithms for probabilistic timed automata to verify qualitative properties, corresponding to satisfaction with probability 0 or 1, as well as quantitative properties, correspon...

We present the tool UFIT (Uppaal Fault Injector for Timed automata). In UFIT, we model five types of faults, namely, message loss, transient, byzantine, stuck-at, and fail-stop faults. Given the fault-free timed automata model and the selection of a type of fault, UFIT models the faults and generates the fault-affected timed automata model automatically. As a result, the designer can analyze th...

This paper describes work in progess performed as part of an ongoing project aimed at the development of theoretical foundations and model checking algorithms for the verification of soft deadlines in timed systems, that is, properties such as “there is a 90% chance that the message will be delivered within 5 time units”. The research is focussed on the probabilistic timed automata model [11], ...

We describe a general automata-theoretic approach for analyzing the veri0cation problems of discrete timed automata (i.e., timed automata with integer-valued clocks) augmented with various data structures. Formally, let C be a class of nondeterministic machines with reversal-bounded counters and possibly other data structures (e.g., a pushdown stack, a queue, a read-write worktape, etc.). Let A...

Multirate timed automata 2] are an extension of timed automata 3] where each clock has its own speed varying between a lower and an upper bound that may change from one control location to another. This formalism is well-suited for specifying hybrid systems where the dynamics of the continuous variables are deened or can be approximated by giving the minimal and maximal rate of change. To avoid...