Service Communautaire d'Information sur la Recherche et le Développement - CORDIS


AMETIST Résumé de rapport

Project ID: IST-2001-35304
Financé au titre de: FP5-IST
Pays: Germany

Optimization and constraint satisfaction as a tool for timed automata analysis

During the second and third years the applicability of mixed integer linear programming (MILP) as a tool for TA analysis has been explored.

An interesting observation is that relaxed models (with integers interpreted as reals) may sometimes give more interesting lower bounds on the costs that extend a partial solution and hence can be used for this purpose with reachability-based algorithms.

All these result were integrated into the prototype tool TAOPT. For bounded horizon problems, questions related to timed automata reachability are transformed into satisfiability problems for difference logic.

Scheduling problem do translate naturally to this logic without going through automata. During the project we have developed a series of solvers for this logic, culminating in the current version of the performant solver DL-SAT and jat.

The tool ELSE can serve as a front end for such solvers by generating efficient difference logic formulae (exploiting partial-order ideas) that correspond to bounded model-checking formulations for timed automata.


Sebastian ENGELL, (Head of Unit)
Tél.: +23-17-555126
Fax: +23-17-555129