Existential Closures for Knowledge Compilation
نویسنده
چکیده
We study the existential closures of several propositional languages L considered recently as target languages for knowledge compilation (KC), namely the incomplete fragments KROM-C, HORN-C, K/H-C, renH-C, AFF, and the corresponding disjunction closures KROM-C[∨], HORN-C[∨], K/H-C[∨], renH-C[∨], and AFF[∨]. We analyze the queries, transformations, expressiveness and succinctness of the resulting languages L[∃] in order to locate them in the KC map. As a by-product, we also address several issues concerning disjunction closures that were left open so far. From our investigation, the language HORN− C[∨, ∃] (where disjunctions and existential quantifications can be applied to Horn CNF formulae) appears as an interesting target language for the KC purpose, challenging the influential DNNF languages.
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