Towards a theory of declarative knowledge
Foundations of deductive databases and logic programming
On the declarative semantics of deductive databases and logic programs
Foundations of deductive databases and logic programming
The well-founded semantics for general logic programs
Journal of the ACM (JACM)
Unrestricted complementation in language equations over a one-letter alphabet
Theoretical Computer Science
Stratified negation in temporal logic programming and the cycle-sum test
Theoretical Computer Science
Journal of Automata, Languages and Combinatorics - Special issue: selected papers of the second internaional workshop on Descriptional Complexity of Automata, Grammars and Related Structures (London, Ontario, Canada, July 27-29, 2000)
Information and Computation
Minimum model semantics for logic programs with negation-as-failure
ACM Transactions on Computational Logic (TOCL)
Temporal stratification tests for linear and branching-time deductive databases
Theoretical Computer Science
Conjunctive Grammars over a Unary Alphabet: Undecidability and Unbounded Growth
CSR '07 Proceedings of the 2nd international symposium on Computer Science in Russia: Theory and Applications
MFCS'05 Proceedings of the 30th international conference on Mathematical Foundations of Computer Science
Well-Founded semantics for boolean grammars
DLT'06 Proceedings of the 10th international conference on Developments in Language Theory
The Complexity Of Local Stratification
Fundamenta Informaticae
Well-founded semantics for Boolean grammars
Information and Computation
A game-theoretic characterization of Boolean grammars
Theoretical Computer Science
Hi-index | 0.00 |
We introduce locally stratified Boolean grammars, a natural subclass of Boolean grammars with many desirable properties. Informally, if a grammar is locally stratified then the set of all pairs of the form (nonterminal, string) of the grammar can be mapped to a (possibly infinite) set of strata so as that the following holds: if the membership of a string w in the language defined by nonterminal A depends on the membership of string w^' in the language defined by nonterminal B, then (B,w^') cannot belong to a stratum higher than the stratum of (A,w); furthermore, if the above dependency is obtained through negation, (B,w^') must belong to a stratum lower than the stratum of (A,w). We prove that local stratifiability can be tested in linear time with respect to the size of the given grammar. We then develop the semantics of locally stratified grammars and prove that it is independent of the choice of the stratification mapping. We argue that the class of locally stratified Boolean grammars appears at present to be the broadest subclass of Boolean grammars that can be given a classical semantics (ie., without resorting to three-valued formal language theory).