Jean-François Raskin

Bio: Jean-François Raskin is an academic researcher from Université libre de Bruxelles. The author has contributed to research in topics: Decidability & Markov decision process. The author has an hindex of 47, co-authored 293 publications receiving 7429 citations. Previous affiliations of Jean-François Raskin include Free University of Brussels & Université de Namur.

Rational Synthesis Under Imperfect Information

Abstract: In this paper, we study the rational synthesis problem for turn-based multiplayer non zero-sum games played on finite graphs for omega-regular objectives. Rationality is formalized by the concept of Nash equilibrium (NE). Contrary to previous works, we consider here the more general and more practically relevant case where players are imperfectly informed. In sharp contrast with the perfect information case, NE are not guaranteed to exist in this more general setting. This motivates the study of the NE existence problem. We show that this problem is ExpTime-C for parity objectives in the two-player case (even if both players are imperfectly informed) and undecidable for more than 2 players. We then study the rational synthesis problem and show that the problem is also ExpTime-C for two imperfectly informed players and undecidable for more than 3 players. As the rational synthesis problem considers a system (Player 0) playing against a rational environment (composed of k players), we also consider the natural case where only Player 0 is imperfectly informed about the state of the environment (and the environment is considered as perfectly informed). In this case, we show that the ExpTime-C result holds when k is arbitrary but fixed. We also analyse the complexity when k is part of the input.

AbsSynthe: abstract synthesis from succinct safety specifications

Abstract: In this paper, we describe a synthesis algorithm for safety specifications described as circuits. Our algorithm is based on fixpoint computations, abstraction and refinement, it uses binary decision diagrams as symbolic data structure. We evaluate our tool on the benchmarks provided by the organizers of the synthesis competition organized within the SYNT'14 workshop.

Time-Bounded Reachability for Monotonic Hybrid Automata: Complexity and Fixed Points

Abstract: We study the time-bounded reachability problem for monotonic hybrid automata (MHA), i.e., rectangular hybrid automata for which the rate of each variable is either always non-negative or always non-positive. In this paper, we revisit the decidability results presented in [5] and show that the problem is NExpTime-complete. We also show that we can effectively compute fixed points that characterise the sets of states that are reachable (resp. co-reachable) within T time units from a given state.

ALASKA: antichains for logic, automata and symbolic Kripke structures analysis

Abstract: ALASKA is a verification tool that implements new algorithms based on antichains [5, 7, 6] to efficiently solve the emptiness problem for both alternating finite automata (AFW) and alternating Buchi automata (ABW). Using the well-known translation from LTL to alternating automata, the tool can decide the satisfiability and validity problems for LTL over finite or infinite words. Moreover, ALASKA can solve the model-checking problem for ABW, LTL, AFW and finite-word LTL over symbolic (BDD-encoded) Kripke structures. © 2008 Springer Berlin Heidelberg.

On the efficient computation of the minimal coverability set of petri nets

Abstract: The minimal coverability set (MCS) of a Petri net is a finite representation of the downward-closure of its reachable markings. The minimal coverability set allows to decide several important problems like coverability, semi-liveness, place boundedness, etc. The classical algorithm to compute the MCS constructs the Karp&Miller (KM) tree [10]. Unfortunately the KM tree is often huge, even for small nets. An improvement of this KM algorithm is the Minimal Coverability Tree (MCT) algorithm [3], which has been introduced nearly 20 years ago, and implemented since then in several tools such as Pep [9]. Unfortunately, we show in this paper that the MCT is flawed: it might compute an under-approximation of the reachable markings. We propose a new solution for the efficient computation of the MCS of Petri nets. Our algorithm is based on new ideas, and the experimental results show that it behaves much better in practice than the KM algorithm.

Phd by thesis

Abstract: Deposits of clastic carbonate-dominated (calciclastic) sedimentary slope systems in the rock record have been identified mostly as linearly-consistent carbonate apron deposits, even though most ancient clastic carbonate slope deposits fit the submarine fan systems better. Calciclastic submarine fans are consequently rarely described and are poorly understood. Subsequently, very little is known especially in mud-dominated calciclastic submarine fan systems. Presented in this study are a sedimentological core and petrographic characterisation of samples from eleven boreholes from the Lower Carboniferous of Bowland Basin (Northwest England) that reveals a >250 m thick calciturbidite complex deposited in a calciclastic submarine fan setting. Seven facies are recognised from core and thin section characterisation and are grouped into three carbonate turbidite sequences. They include: 1) Calciturbidites, comprising mostly of highto low-density, wavy-laminated bioclast-rich facies; 2) low-density densite mudstones which are characterised by planar laminated and unlaminated muddominated facies; and 3) Calcidebrites which are muddy or hyper-concentrated debrisflow deposits occurring as poorly-sorted, chaotic, mud-supported floatstones. These

Tools and Algorithms for the Construction and Analysis of Systems. Proc. TACAS 2009

Abstract: ing WS1S Systems to Verify Parameterized Networks . . . . . . . . . . . . 188 Kai Baukus, Saddek Bensalem, Yassine Lakhnech and Karsten Stahl FMona: A Tool for Expressing Validation Techniques over Infinite State Systems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 204 J.-P. Bodeveix and M. Filali Transitive Closures of Regular Relations for Verifying Infinite-State Systems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 220 Bengt Jonsson and Marcus Nilsson Diagnostic and Test Generation Using Static Analysis to Improve Automatic Test Generation . . . . . . . . . . . . . 235 Marius Bozga, Jean-Claude Fernandez and Lucian Ghirvu Efficient Diagnostic Generation for Boolean Equation Systems . . . . . . . . . . . . 251 Radu Mateescu Efficient Model-Checking Compositional State Space Generation with Partial Order Reductions for Asynchronous Communicating Systems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 266 Jean-Pierre Krimm and Laurent Mounier Checking for CFFD-Preorder with Tester Processes . . . . . . . . . . . . . . . . . . . . . . . 283 Juhana Helovuo and Antti Valmari Fair Bisimulation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 299 Thomas A. Henzinger and Sriram K. Rajamani Integrating Low Level Symmetries into Reachability Analysis . . . . . . . . . . . . . 315 Karsten Schmidt Model-Checking Tools Model Checking Support for the ASM High-Level Language . . . . . . . . . . . . . . 331 Giuseppe Del Castillo and Kirsten Winter Table of

PDDL2.1: an extension to PDDL for expressing temporal planning domains

Abstract: In recent years research in the planning community has moved increasingly towards application of planners to realistic problems involving both time and many types of resources. For example, interest in planning demonstrated by the space research community has inspired work in observation scheduling, planetary rover exploration and spacecraft control domains. Other temporal and resource-intensive domains including logistics planning, plant control and manufacturing have also helped to focus the community on the modelling and reasoning issues that must be confronted to make planning technology meet the challenges of application. The International Planning Competitions have acted as an important motivating force behind the progress that has been made in planning since 1998. The third competition (held in 2002) set the planning community the challenge of handling time and numeric resources. This necessitated the development of a modelling language capable of expressing temporal and numeric properties of planning domains. In this paper we describe the language, PDDL2.1, that was used in the competition. We describe the syntax of the language, its formal semantics and the validation of concurrent plans. We observe that PDDL2.1 has considerable modelling power -- exceeding the capabilities of current planning technology -- and presents a number of important challenges to the research community.

Lazy abstraction

Abstract: One approach to model checking software is based on the abstract-check-refine paradigm: build an abstract model, then check the desired property, and if the check fails, refine the model and start over. We introduce the concept of lazy abstraction to integrate and optimize the three phases of the abstract-check-refine loop. Lazy abstraction continuously builds and refines a single abstract model on demand, driven by the model checker, so that different parts of the model may exhibit different degrees of precision, namely just enough to verify the desired property. We present an algorithm for model checking safety properties using lazy abstraction and describe an implementation of the algorithm applied to C programs. We also provide sufficient conditions for the termination of the method.