133 views122 votes15 years 1 months ago FSTTCS 2010»
We study the propositional satisfiability problem (SAT) on classes of CNF formulas (formulas in Conjunctive Normal Form) that obey certain structural restrictions in terms of thei...
A concept language with role intersection and number restriction is defined and its modal equivalent is provided. The main reasoning tasks of satisfiability and subsumption checkin...
120 views121 votes15 years 3 months ago CORR 2008»
Modal logics are widely used in computer science. The complexity of modal satisfiability problems has been investigated since the 1970s, usually proving results on a case-by-case b...
136 views132 votes15 years 14 days ago ENTCS 2010»
We present MLSolver, a tool for solving the satisfiability and validity problems for modal fixpoint logics. The underlying technique is based on characterisations of satisfiabilit...
105 views105 votes15 years 4 months ago AIML 2004»
We study and give a summary of the complexity of 15 basic normal monomodal logics under the restriction to the Horn fragment and/or bounded modal depth. As new results, we show tha...
111 views125 votes14 years 10 months ago JAPLL 2010»
The satisfiability problem of hybrid logics with the downarrow binder is known to be undecidable. This initiated a research program on decidable and tractable fragments. In this p...
105 views125 votes15 years 6 months ago CADE 2006»
We introduce a Presburger modal logic PML with regularity constraints and full Presburger constraints on the number of children that generalize graded modalities, also known as num...
115 views140 votes15 years 2 months ago FUIN 2000»
We give algorithms to construct the least L-model for a given positive modal logic program P, where L can be one of the modal logics KD, T, KDB, B, KD4, S4, KD5, KD45, and S5. If L...
140 views122 votes16 years 3 months ago CADE 2001»
RACER implements a TBox and ABox reasoner for the logic SHIQ. RACER was the first full-fledged ABox description logic system for a very expressive logic and is based on optimized s...