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Characterizing the Complexity of Boolean Functions represented by Well-Structured Graph-Driven Parity-FBDDs

Henrik Brosenne, Matthias Homeister, Stephan Waack (2010)

RAIRO - Theoretical Informatics and Applications

We investigate well-structured graph-driven parity-FBDDs, which strictly generalize the two well-known models parity OBDDs and well-structured graph-driven FBDDs. The first main result is a characterization of the complexity of Boolean functions represented by well-structured graph-driven parity-FBDDs in terms of invariants of the function represented and the graph-ordering used. As a consequence, we derive a lower bound criterion and prove an exponential lower bound for certain linear code functions. The...

Correctness of horizontal and vertical composition for implementation concepts based on constructors and abstractors.

Hartmut Ehrig, Hans-Jörg Kreowski, Fernando Orejas (1997)

Revista Matemática de la Universidad Complutense de Madrid

A new implementation concept for parameterized specifications based on constructors and abstractors was recently introduced by Orejas, Navarro and Sánchez which includes most of the implementation concepts in the literature for initial as well as loose semantics. In this paper we redefine vertical and different kinds of horizontal compositions using the new concept of semi-pushout defined for a mixture of signature and specification morphisms. The main results concerning correctness of horizontal...

Efficiency of automata in semi-commutation verification techniques

Gérard Cécé, Pierre-Cyrille Héam, Yann Mainier (2008)

RAIRO - Theoretical Informatics and Applications - Informatique Théorique et Applications

Computing the image of a regular language by the transitive closure of a relation is a central question in regular model checking. In a recent paper Bouajjani et al. [IEEE Comput. Soc. (2001) 399–408] proved that the class of regular languages L – called APC – of the form j L 0 ...

Efficiency of automata in semi-commutation verification techniques

Gérard Cécé, Pierre-Cyrille Héam, Yann Mainier (2007)

RAIRO - Theoretical Informatics and Applications

Computing the image of a regular language by the transitive closure of a relation is a central question in regular model checking. In a recent paper Bouajjani et al. [IEEE Comput. Soc. (2001) 399–408] proved that the class of regular languages L – called APC – of the form UjL0,jL1,jL2,j...Lkj,j, where the union is finite and each Li,j is either a single symbol or a language of the form B* with B a subset of the alphabet, is closed under all semi-commutation relations R. Moreover a recursive...

Fixpoint alternation: arithmetic, transition systems, and the binary tree

J. C. Bradfield (2010)

RAIRO - Theoretical Informatics and Applications

We provide an elementary proof of the fixpoint alternation hierarchy in arithmetic, which in turn allows us to simplify the proof of the modal mu-calculus alternation hierarchy. We further show that the alternation hierarchy on the binary tree is strict, resolving a problem of Niwiński.

Formal Methods to Improve Public Administration Business Processes

Andrea Polini, Andrea Polzonetti, Barbara Re (2012)

RAIRO - Theoretical Informatics and Applications - Informatique Théorique et Applications

Starting from late 90’s the public administration has started to employ a quite relevant amount of its budget in developing ICT solutions to better deliver services to citizens. In spite of this effort many statistics show that the mere availability of ICT based services does not guarantee per se their usage. Citizens have continued to largely access services through “traditional” means. In our study we suggest that the highlighted situation is partly due to the fact that relevant domain dependent...

Formal Methods to Improve Public Administration Business Processes

Andrea Polini, Andrea Polzonetti, Barbara Re (2012)

RAIRO - Theoretical Informatics and Applications

Starting from late 90’s the public administration has started to employ a quite relevant amount of its budget in developing ICT solutions to better deliver services to citizens. In spite of this effort many statistics show that the mere availability of ICT based services does not guarantee per se their usage. Citizens have continued to largely access services through “traditional” means. In our study we suggest that the highlighted situation is partly...

Formally certified floating-point filters for homogeneous geometric predicates

Guillaume Melquiond, Sylvain Pion (2007)

RAIRO - Theoretical Informatics and Applications

Floating-point arithmetic provides a fast but inexact way of computing geometric predicates. In order for these predicates to be exact, it is important to rule out all the numerical situations where floating-point computations could lead to wrong results. Taking into account all the potential problems is a tedious work to do by hand. We study in this paper a floating-point implementation of a filter for the orientation-2 predicate, and how a formal and partially automatized verification of this...

Currently displaying 21 – 40 of 105