Methods for deciding quantifier-free non-linear arithmetical conjectures over R are crucial in the formal verification of many realworld systems and in formalised mathematics. Wh...
This paper is a sequel to the papers [4, 6] in which an alternative skolemization method called ekolemization was introduced that, when applied to the strong existential quantifie...
We shed light on the connections between different approaches to constraint satisfaction by showing that the main consistency concepts used to derive tractability results for cons...
Abstract. Logic preservation theorems often have the form of a syntax/semantics correspondence. For example, the Los-Tarski theorem asserts that a rst-order sentence is preserved b...
Unions of conjunctive queries, also known as select-project-join-union queries, are the most frequently asked queries in relational database systems. These queries are definable b...