New logical and complexity results for Signed-SAT

We define Mv-formulas as the union of the subclasses of signed CNF formulas known as regular and monosigned CNF formulas, and then define resolution calculi that are refutation complete for Mv-formulas and give new complexity results for the Horn-SAT and 2-SAT problems. Our goal is to use Mv-formulas as a constraint programming language between CSP and SAT, and solve computationally difficult combinatorial problems with efficient satisfiability solvers for Mv-formulas. The results presented in this paper provide evidence that Mv-formulas are a problem modeling language that offers a good compromise between complexity and expressive power.