Satisfiability of CTL* with constraints

We show that satisfiability for CTL* with equality-, order-, and modulo-constraints over Z is decidable. Previously, decidability was only known for certain fragments of CTL*, e.g., the existential and positive fragments and EF.Comment: To appear at Concur 201

Quantitative Modal Transition Systems

International audienceThis extended abstract offers a brief survey presentation of the specification formalism of modal transition systems and its recent extensions to the quantitative setting of timed as well as stochastic systems. Some applications will also be briefly mentioned

Comparing the Expressive Power of Well-structured Transition Systems

We compare the expressive power of a class of well-structured transition systems that includes relational automata, Petri nets, lossy channel systems, and constrained multiset rewriting systems. For each one of these models we study the class of languages generated by labelled transition systems describing their semantics. We consider here two types of accepting conditions: coverability and reachability of a given configuration. In both cases we obtain a strict hierarchy in which constrained multiset rewriting systems is the the most expressive model

Baseline evaluation of Early Learning Initiative. Final report.

This study is a synthesis of the key findings from a two-year evaluation (2009-2011) of the National College of Ireland’s Early Learning Initiative. The study also relied on data from interviews with stakeholders and parents, and from an end of evaluation consultation with the ELI team. The aim of the study is to provide a guide to the ELI in the future development of its programme. The Early Learning Initiative (ELI) is a community-based educational initiative aimed at improving educational outcomes for children in the Dublin Docklands. The initiative provides support and training to parents, families and educators through a series of programmes and activities. The ELI operates as part of the National College of Ireland (NCI) and has been delivering educational programmes in the Docklands since 2006

On the decidability of the reachability problem for planar differential inclusions

Abstract. In this paper we develop an algorithm for solving the reachability problem of two-dimensional piece-wise rectangular differential inclusions. Our procedure is not based on the computation of the reach-set but rather on the computation of the limit of individual trajectories. A key idea is the use of one-dimensional affine Poincar maps for which we can easily compute the fixpoints. As a first step, we show that between any two points linked by an arbitrary trajectory there always exists a trajectory without self-crossings. Thus, solving the reachability problem requires considering only those. We prove that, indeed, there are only finitely many “qualitative types ” of those trajectories. The last step consists in giving a decision procedure for each of them. These procedures are essentially based on the analysis of the limits of extreme trajectories. We illustrate our algorithm on a simple model of a swimmer spinning around a whirlpool.