Modeling Time in Computing: A Taxonomy and a Comparative Survey

The increasing relevance of areas such as real-time and embedded systems, pervasive computing, hybrid systems control, and biological and social systems modeling is bringing a growing attention to the temporal aspects of computing, not only in the computer science domain, but also in more traditional fields of engineering. This article surveys various approaches to the formal modeling and analysis of the temporal features of computer-based systems, with a level of detail that is suitable also for non-specialists. In doing so, it provides a unifying framework, rather than just a comprehensive list of formalisms. The paper first lays out some key dimensions along which the various formalisms can be evaluated and compared. Then, a significant sample of formalisms for time modeling in computing are presented and discussed according to these dimensions. The adopted perspective is, to some extent, historical, going from "traditional" models and formalisms to more modern ones.Comment: More typos fixe

Comments on temporal logics for real-time system specification

The article “Temporal Logics for Real-Time System Specification” surveys some of the relevant literature dealing with the use of temporal logics for the specification of real-time systems. Unfortunately, it introduces some imprecisions that might create some confusion in the reader. While a certain degree of informality is certainly useful when addressing a broad audience, imprecisions can negatively impact the legibility of the exposition. We clarify some of its remarks on a few topics, in an effort to contribute to the usefulness of the survey for the reade