J. Rintanen. Improvements to the evaluation of quantified boolean formulae. In Proceedings of the 16th International Joint Conference on Artificial Intelligence (IJCAI - 99), 1999.  Home/Search   Document Details and Download   Summary   Related Articles   Check

....are harder than , and thus not polynomially reducible to SAT testing. Moreover, these problems cannot be reduced to any solver for problems that are located in the Polynomial Hierarchy. On the other hand, they are solvable in polynomial space, and thus reducible to a QBF solver (e.g. [4, 32, 8]) in polynomial time. Furthermore, testing probabilistic causal irrelevance is easier than C complete problems, which could perhaps help in finding polynomial time (randomized) approximation algorithms for this problem. We remark that for computing the conditional probability over two causal ....

J. Rintanen. Improvements to the evaluation of quantified boolean formulae. In Proceedings IJCAI-99, pages 1192--1197, 1999.

....be utilized for this purpose, or the diagnostic frontend of the DLV system [10] Another possibility would be an encoding of causal explanations in Answer Set Programming, and using the DLV engine to compute solutions. For the case of general causal explanations, reductions to QBF solvers such as [5, 41, 19] could be used. 7.2 Bayesian Networks After Cooper s well known intractability result [7] for probabilistic inference in Bayesian networks, a number of papers in this area have investigated complexity issues for reasoning and in particular for explanation finding. A dominating notion of ....

.... with complexity up to , such as DLV [13] However, an explanation may be computed using nested backtracking, or flat backtracking calling a subroutine for tasks (e.g. calls to DLV) A further possible perspective are translations to QBF solvers, which proved valuable in other applications [41]. We can compute an partial explanation similarly. Computing a best one amounts to an optimization problem, which can be solved by binary search over the range [0,1] of , and thus in polynomial time with a oracle. A substantially faster algorithm seems unlikely to exist. Once the basic ....

J. Rintanen. Improvements to the evaluation of quantified Boolean formulae. In Proceedings IJCAI-99, pages 1192--1197, 1999.

....all such assignments. Q ALL SAT is a special form of a quantified Boolean formula which contains two subformulas in conjunctive normal form (CNF) First solution algorithms for quantified Boolean formulas have been constructed, for example, by Cadoli, Giovanardi, and Schaerf [2] and Rintanen [7]. These algorithms consider the case where all quantifiers constitute a prefix of a CNF formula. They cannot be applied to logic based abduction. We will propose algorithms for Q ALL SAT and its related problems that can take advantage of any efficient SAT solver and of any solver for the related ....

Rintanen, J.: Improvements to the evaluation of quantified Boolean formulae. Proceedings of the Sixteenth International Joint Conference on Artificial Intelligence (1999) 1192-1197

....approach is to translate (in polynomial time) a given reasoning task into the evaluation problem for QBFs and then use a QBF evaluator to compute the resultant instances. The existence of efficient QBF solvers, such as the systems developed by Cadoli et al. 4] Giunchiglia et al. 18] Rintanen [32] , or Feldmann et al. 15] makes such a rapid prototyping approach practicably applicable. A similar approach for solving various reasoning tasks belonging to the area of nonmonotonic reasoning has been realized in the system QUIP [12; 11; 27] This prototype implementation currently handles ....

J. Rintanen. Improvements to the Evaluation of Quantified Boolean Formulae. In Proceedings of the International Joint Conference on Artificial Intelligence, pages 1192--1197, 1999.

....base. Anyway the PSPACE upper bound of the complexity of reasoning, and the similarity of their semantics with that of quantified Boolean formulas (QBFs) makes fast prototype implementations possible by translating them into a QBF and then using one of the several available solvers, e.g. [44]. This approach could be used also for implementing meaningful fragments of NATs, such as the one in [3] although this might be inefficient, like using a first order theorem prover for propositional logic. Given that QBFs can be polynomially encoded into NATs, we can show that nested ....

....related KR formalism or logic, or by designing genuine algorithms. Su s CS program [49] and Doherty et al. s DLS algorithm [16, 28] which handle the case of predicate logic, are incomplete in general and presumably not highly efficient in the propositional context. The use of QBF solvers (e.g. [11, 44, 23]) is here a suggestive starting point for obtaining more suitable systems. As we believe, addressing these issues is worthwhile since nesting circumscriptions is a natural generalization of circumscription, and yields, as shown by our results, a simple yet expressive knowledge representation ....

J. Rintanen. Improvements to the evaluation of quantified Boolean formulae. In Proceedings IJCAI '99, pages 1192--1197. AAAI Press, 1999.

....theorem provers for logics with complexity up to 2 are needed as host for efficient translations. For example, DLV [78] DeRes [23] or a disjunctive extension of smodels [75] which all provide this expressiveness, might be used, as well as theorem provers based on quantified Boolean formulas [20, 83, 32]. However, efficient transformations of the problems to these logics remain to be designed. In the case of problems with complexity P , such translations might not be very appealing, since the theorem provers mentioned above are tailored for solving problems whose complexity characteristics ....

J. Rintanen. Improvements to the evaluation of quantified Boolean formulae. In Proc. 16th International Joint Conference on Artificial Intelligence (IJCAI-99), Stockholm, Sweden, pp. 1192--1197. Morgan Kaufmann, 1999.

....idea is to translate a given reasoning task into a quantified Boolean formula (QBF) and then applying some sophisticated QBF solver to evaluate the translated QBF. The existence of efficient QBF solvers, like, e.g. the systems developed by Cadoli et al. 5] Giunchiglia et al. 18] Rintanen [37], Letz [25] or Feldmann et al. 15] makes this reduction approach practicably applicable. Concerning the particular reductions, we provide efficient (polynomial time) translations of reasoning tasks for the following modal nonmonotonic logics: Moore s autoepistemic logic [29] nonmonotonic ....

....by the availability of several practicably efficient QBF solvers. Among the different tools, there is a propositional theorem prover, boole, based on binary decision diagrams, a system using a generalised resolution principle [23] several provers implementing an extended Davis Putnam procedure [5, 15, 18, 25, 37], as well as a distributed algorithm running on a PC cluster [15] With the exception of boole, these tools do not accept arbitrary QBFs, but require the input formula to be in prenex conjunctive normal form. To avoid an exponential increase of formula size, structure preserving normal form ....

[Article contains additional citation context not shown here]

J. Rintanen. Improvements to the Evaluation of Quantified Boolean Formulae. In Proc. IJCAI-99, pages 1192--1197, 1999.

.... remained objects of purely theoretical interest for years, and it is only very recently that solvers have been implemented to solve Quantified Boolean Formulae (QBF) All of the algorithms we are aware of either rely on or generalize SAT algorithms, such as resolution [5] Davis Putnam and DLL [7, 18], or backtracking and improvements [14] due to space restrictions we do not cite all recent related publications) In this paper, we propose to study the general problem of quantified constraints over arbitrary finite domains, of which the boolean case is a particular instance. We attempt to ....

....primitive QCPs. Example 4. Example 2, continued) To check arc consistency for y) we have to determine consistency for the two problems conj) and #y#conj (conj = y) Consider the QCP 9. k = mod) To check arc consistency, we have to consider each of the primitive QCPs: [0, 18](x y = sum) 0, 9] 9.k = k # ) 0, 9] sum k # = mod) Note that the term arc consistency is to be understood in the sense of consistent w.r.t. each constraint , a definition used for instance by [10] and hence somewhat di#erent from the more classical, binary ....

J. Rintanen. Improvements to the evaluation of quantified boolean formulae. In Proc. of the 16th Int. Joint Conf. on AI (IJCAI), pages 1192--1197, Stockholm, Sweden, 1999. Morgan Kaufmann.

....of maturity; there are many success stories where SAT solvers such as [11, 19, 22] have been successfully applied to industrial scale problems. However, the picture for QBL is rather di#erent. Despite the growing body of research on this topic, the current generation of Q(uantified)SAT solvers [8, 10, 15] are still in their infancy. These tools work by translating QBL formulae to formulae in a quantified clausal normal form and applying extensions of the Davis Putnam method to the result. The extensions concern generalizing Davis Putnam heuristics such as unit propagation and backjumping. These ....

....quantifier expansion are also used in Williams et al. 20] to optimize di#erent computation tasks like the calculation of fixed points. Most QBL algorithms generalize the Davis Putnam procedure to operate on formulae transformed into quantified clausal normal form. Cadoli et al. 6] and Rintanen [16, 15] present di#erent heuristic extensions of the Davis Putnam method. Cadoli et al. s techniques were tuned for randomly generated problems and Rintanen s strategies were specially designed for planning problems whose quantifiers have a fixed ### structure. Other work includes that of Letz [10] and ....

[Article contains additional citation context not shown here]

Jussi Rintanen. Improvements to the evaluation of quantified boolean formulae. In Dean Thomas, editor, Proceedings of the 16th International Joint Conference on Artificial Intelligence (IJCAI-99-Vol2). Morgan Kaufmann Publishers, S.F., July 31--August 6 1999.

.... problems like planning or various forms of nonmonotonic reasoning by encoding them into quantified Boolean formulas (QBFs) and computing the truth value of the resultant formulas with a QBF solver has become an attractive and increasingly important research topic over the last years (cf. e.g. [12, 5, 4, 11]) The QBFs resulting from the encodings are usually not in a specific normal form which prevents the application of most of the available QBF provers [9, 3, 6, 8, 10, 12] without a translation into normal form. The only kind of QBF solvers which can handle arbitrary formulas is based on binary ....

.... formulas with a QBF solver has become an attractive and increasingly important research topic over the last years (cf. e.g. 12, 5, 4, 11] The QBFs resulting from the encodings are usually not in a specific normal form which prevents the application of most of the available QBF provers [9, 3, 6, 8, 10, 12] without a translation into normal form. The only kind of QBF solvers which can handle arbitrary formulas is based on binary decision diagrams (BDDs) In order to make more practicably successful QBF solvers available for solving the encoded problems, a transformation of an arbitrary QBF into a ....

J. Rintanen. Improvements to the Evaluation of Quantified Boolean Formulae. In Proceedings of the 16th International Joint Conference on Artificial Intelligence (IJCAI-99), pages 1192--1197, 1999.

....the SGP and GPT conditional planners. Another interesting system is QBFPLAN [Rin99a] that extends the SAT based approach to planning to the case of nondeterministic domains. The planning problem is reduced to a QBF satisfiability problem, that is then given in input to an efficient solver [Rin99b] QBFPLAN relies on a symbolic representation, but the approach seems to be limited to plans with a bounded execution length. The search space is significantly reduced by providing the branching structure of the plan as an input to the planner. The problem of planning under partial observability ....

J. Rintanen. Improvements to the Evaluation of Quantified Boolean Formulae. In T. Dean, editor, 16th Iinternational Joint Conference on Artificial Intelligence, pages 1192--1197. Morgan Kaufmann Publishers, August 1999.

....minimum a satisfying assignment; satz [30] 45] satz.v213 [30] 45] satz rand.v4.6 [19] 45] eqsatz.v20 [31] GSAT.v41 [45] 47] WalkSAT.v37 [45] 46] posit [16] 45] ntab [13] 45] rel sat.1.0 and rel sat.2. 1 [3] 45] rel sat rand1.0 [19] 45] ASAT and C SAT [15] CLS [41] QSAT [39] and QBF [42], two SAT checkers for quantified Boolean formulas; ZRes [11] a SAT checker combining ZeroSupressed BDDs (ZBDDs) with the original Davis Putnam procedure; BSAT and IS USAT, both based on BDDs and exploiting the properties of unate Boolean functions [29] Prover, a commercial SAT checker based on ....

J. Rintanen, "Improvements to the Evaluation of Quantified Boolean Formulae, " International Joint Conference on Artificial Intelligence (IJCAI '99), August 1999, pp. 1192-1197.

....is a much more powerful reasoning method than circumscription, and that it can not be reduced in polynomial time to circumscription. Thus, circumscriptive theorem provers can not be efficiently used for curb reasoning. On the other hand, a curb theorem prover could be based on a QBF solver (see [10, 4, 16, 1, 9]) After proving our main result, we identify classes of theories for which the complexity of curbing is located at a lower complexity level. Specifically, we show that if a 2 theory T has the lub property, that is, every set of good models of T has a least (unique minimal) upper bound, then ....

J. Rintanen. Improvements to the Evaluation of Quantified Boolean Formulae. In Proc. IJCAI '99, pp. 1192--1197. AAAI Press, 1999.

....to solve it) can now compete and even outperform specialized domain dependent solvers. Another area of research is to use the results obtained for SAT algorithms on related domains: computation of implicant cover[SC96] prime implicants implicates [CC96] Quantified Boolean Formulas[CGS98, Rin99] DISTANCE SAT[BM99] etc. Our work follows this idea: we show how to modify the famous Davis and Putnam method to compute some specific part of the implicants. Although the usage of DPLL to compute implicants is not new, we compute implicants minimal with respect of some of their literals only, ....

Jussi Rintanen. Improvement to the evaluation of quantified boolean formulae. In Proceedings of the Sixteenth International Joint Conference on Artificial Intelligence (IJCAI'99), pages 1192--1197, 1999.

.... Our complexity results give a clear picture of the feasibility of polynomial time translations for particular planning problems into computational logic systems such as Blackbox [37] CCALC [47] smodels [33] DLV, satisfiability checkers, e.g. 2, 74] or Quantified Boolean Formula (QBF) solvers [4, 61, 18]. INFSYS RR 1843 01 11 1.3 Structure of the Paper The rest of the paper is structured as follows. The next section formally introduces the language K, and provides the syntax and formal semantics of the core language, as well as enhancements of the language by macro constructs that are useful ....

.... for implementation The complexity results have important consequences for the implementation of K on top of existing computational logic systems, such as Blackbox [37] CCALC [47] smodels [33] DLV, satisfiability checkers, e.g. 53, 41, 2, 74] or Quantified Boolean Formula (QBF) solvers [4, 61, 18]. Optimistic Planning under arbitrary plan length is not polynomially reducible to systems with capability of solving problems within the Polynomial Hierarchy, e.g. Blackbox, satisfiability checkers, CCALC, smodels, or DLV, while it is feasible using QBF solvers. On the other hand, for fixed (and ....

J. Rintanen. Improvements to the evaluation of quantified boolean formulae. In T. Dean, editor, Proceedings of the Sixteenth International Joint Conference on Artificial Intelligence (IJCAI)

No context found.

J. Rintanen. Improvements to the evaluation of quantified boolean formulae. In Proceedings of the 16th International Joint Conference on Artificial Intelligence (IJCAI - 99), 1999.

No context found.

J. Rintanen. Improvements to the evaluation of quantified Boolean formulae. In Proceedings of the 16th International Joint Conference on Artificial Intelligence (IJCAI '99), pages 1192-- 1197, Stockholm, Sweden, 1999.

No context found.

Jussi Rintanen. Improvements to the evaluation of quantified Boolean formulae. In Proceedings of the Sixteenth International Joint Conference on Artificial Intelligence (IJCAI'99), July 31-August 6, Stockholm, Sweden, pages 1192--1197. Morgan Kaufmann, 1999.

No context found.

J. Rintanen. Improvements to the Evaluation of Quantified Boolean Formulae. In Proc. IJCAI-99, pages 1192--1197, 1999.

No context found.

J. Rintanen. Improvements to the evaluation of quantified boolean formulae. In Proc. of the 16th Int. Joint Conf. on AI (IJCAI), pages 1192--1197, Stockholm, Sweden, 1999. Morgan Kaufmann.

No context found.

Rintanen, J.: Improvements to the evaluation of quantified boolean formulae. In: IJCAI-99. (1999) 1192--1197

No context found.

Rintanen, J.: Improvements to the evaluation of quantified boolean formulae. In: IJCAI-99. (1999) 1192--1197

No context found.

J. Rintanen. Improvements to the evaluation of quantified boolean formulae. In IJCAI-99, pages 1192--1197, 1999.

No context found.

Rintanen, J.: 1999b, `Improvements to the Evaluation of Quantified Boolean Formulae'. In: T. Dean (ed.): Proceedings of the 16th International Joint Conference on Artificial Intelligence (IJCAI'99). pp. 1192--1197.

No context found.

:323--352. Rintanen, J. 1999b. Improvements to the Evaluation of Quantified Boolean Formulae. In Proc. IJCAI-99, 1192--

First 50 documents

Online articles have much greater impact   More about CiteSeer.IST   Add search form to your site   Submit documents   Feedback  

CiteSeer.IST - Copyright Penn State and NEC