
...we consider deciding whether a disjunction of horn theories is hor n, and, if not, computing a horn core (i.e., a maximal horn theory included in this disjunction) and horn envelope (i.e., the minimum horn theory including the disjunction). the problems are investigated for...

...we consider deciding whether a disjunction of horn theoriesis horn, and, if not, computing a horn core, i.e., a maximal horn theoryincluded in this disjunction. the problems are investigated for different representationsof horn theories, namely for horn cnfs and characteristic models. whilethe problems are...

...base. in general, the difference of horn theories is not horn. therefore, we consider horn approximations of the difference in terms of horn cores (i.e., weakest horn theories included in the differen ce), which have been proposed and analyzed extensively in the literature...

...base. in general, the difference of horn theories is not horn. therefore, we consider horn approximations of the difference in terms of horn cores (i.e., weakest horn theories included in the difference), which have been proposed and analyzed extensively in the literature...

...on the logicosyntactic properties of negation and disjunction (or) and tests knowledge of (a) core syntactic relations (scope and ccommand), (b) core semantic relations (entailment relations and demorgan's laws of propositional logic), and (c) the relationship between (a) and (b). we examine the performance of individuals with ws, children matched...

...learning firstorder functionfree horn expressions from interpretations. the system is based on an algorithm that learns by asking questions and that was proved correct in...h system implements these algorithms and adds several facilities and optimizations that allow efficient applications in a wide range of problems. as one of the important ingredients, the system...

...be reduced to the satisfiability of sets of ground literals in theory t. if a sound and complete inference system for first...satisfiability procedure. we prove termination of a rewritebased firstorder engine on the theories of records, integer offsets, integer offsets modulo and lists. we give a modularity...

...on satisfiable instances. satisfiability modulo theories (smt) solvers have proven highly scalable,
efficient and suitable for integrated theory reasoning. superpositionbased inference systems...with
equalities, universally quantified variables, and horn clauses. we describe a calculus that tightly integrates superposition
and smt solvers. the combination is...

...be done with the help of generalized logic programs. we start by introducing the core of prolog, which is based on...defaultnegation, explicit negation, preferences, and disjunction. the need for these extensions is motivated by suitable examples and the corresponding semantics are discussed...

...we survey the parameterized complexity of problems that arise in artificial intelligence, database theory, and automated reasoning. in particular, we...logic programs, for a number of other problems of nonmonotonic reasoning, and for the computation of cores in data exchange....