A set of experiments were designed to measure the enhancement to alphabeta search using refutation and transposition tables. Results indicate that the use of transposition tables can reduce the size of the game tree by as much as 95%, significantly improving the algorithmic performance of αβ search. Seven replacement schemes to handle collisions in transposition tables were proposed and their p...

different concepts and approaches toward god in western theology and philosophy, from greek period to modern age, has regarded from negative theology view point. but this concepts and approaches at the same time can be regarded from new perspective in modern age. in other word, it can be shown that in the modern age we can see a negative theology, i.e. refutation of resemblance between god and ...

A new form of width restricted resolution, called \CUBI resolution" (\closure under bounded input resolution") is presented. CUBI resolution allows to eliminate the dependence on the maximal input clause length in the general lower bound for resolution from Ben-Sasson, Wigderson 99], and also the poly-time decidability problem about \k-resolution" ((Kleine B uning 93]) is bypassed (by slightly ...

One of the main reasons why computer generated proofs are not widely accepted is often their complexity and incomprehensibility. Especially proofs of mathematical theorems with equations are normally presented in an inadequate and not intuitive way. This is even more of a problem for the presentation of inferences drawn by automated reasoning components in other Al systems. For first order logi...

In the framework of ARISE project (Automatic Railways Inquiry Systems for Europe) we developed DEMON, a real time spontaneous speech dialogue system allowing mixed initiative. This system gives information for train connection. On this system three different confirmation strategies were developed and compared with regard to erroneous confirmation rates. The first strategy was implicit confirmat...

A static model for the parallel execution of logic programs on MIMD distributed memory systems is presented where a refutation is implemented through a process network returned by the compilation of the logic program. The model supports Restricted-AND, OR and stream parallelism and it is integrated with a set of static analyses to optimise the process network. Altogether, the processes interact...

In this paper we provide a new method to generate hard k-SAT instances. Basically, we construct the bipartite incidence graph of a k-SAT instance where the left side represents the clauses and the right side represents the literals of our Boolean formula. Then, the clauses are filled by incrementally connecting both sides while keeping the girth of the graph as high as possible. That assures th...

Input Distance ( ) is introduced as a metric for propositional resolution derivations. If F = Ci is a formula and D is a clause, then (D;F) is de ned as minijD Cij. The for a derivation is the maximum of any clause in the derivation. Input Distance provides a re nement of the clause-width metric analyzed by Ben-Sasson and Wigderson (JACM 2001) in that it applies to families whose clause width g...

In previous work, an attempt was made to apply the schematic CERES method [8] to a formal proof with an arbitrary number of Π2 cuts (a recursive proof encapsulating the infinitary pigeonhole principle) [5]. However the derived schematic refutation for the characteristic clause set of the proof could not be expressed in the formal language provided in [8]. Without this formalization a Herbrand s...

We present procedures to compile any propo-sitional clausal database into a logically equivalent \compiled" database ? such that, for any clause C, j = C if and only if there is a unit refutation of ? :C. It follows that once the compilation process is complete any query about the logical consequences of can be correctly answered in time linear in the sum of the sizes of ? and the query. The co...