Abstract. In this paper we introduce a variant of temporal logic tailored for specifying desired properties of continuous signals. The logic is based on a bounded subset of the real-time logic MITL, augmented with a static mapping from continuous domains into propositions. From formulae in this logic we create automatically property monitors that can check whether a given signal of bounded length and finite variability satisfies the property. A prototype implementation of this procedure was used to check properties of simulation traces generated by Matlab/Simulink. 1

Computer systems play an increasingly prominent role in our daily lives. Interacting with these systems often involves disclosing personal data, i.e., data that can be traced back to particular individuals, collected in different contexts. For example, healthcare providers, insurance companies, and tax

Formal techniques have been widely applied in the design of real-time systems and have significantly helped detect design errors by checking real-time properties of the model. However, a model is only an approximation of its realization in terms of the issuing time of events. Therefore, a real-time property verified in the model can not always be directly transferred to the realization. In this paper, both the model and the realization are viewed as sets of timed state sequences. In this context, we first investigate the real-time property preservation between two neighbouring timed state sequences (execution traces of timed systems), and then extend the results to two "neighbouring" timed systems. The study of real-time property preservation gives insight in building a formal link between real-time properties satisfied in the model and those in the realization.

In this paper we describe an event-based algorithm for runtime verification of timed linear temporal logic. The algorithm is based on a rewriting of the formula expressing a desired or undesired property of a timed system. Rewriting takes place, at discrete points in time, but only when there is a relevant statechange taking place in the timed system, or a deadline, determined by the formula, has been passed. By limiting the rewriting to only points in time where an event occurs, and not at all discrete time-points, makes the algorithm useful in situations where there are large data sets and large di#erences in the relevant time scales (ranging perhaps from milliseconds to months as in business software).

This paper presents a verification technique for dense-time MTL based on discretization. The technique reduces the validity problem of MTL formulas from dense to discrete time, through the notion of sampling invariance, introduced in previous work [FR06]. Since the reduction is from an undecidable problem to a decidable one, the technique is necessarily incomplete, so it fails to provide conclusive answers on some problem instances. The paper discusses this shortcoming and hints at how it can be mitigated in practice. The verification technique has been implemented on top of a tool for discrete-time bounded validity checking; the paper also reports on in-the-small experiments with the tool, which show some