D. Loveland, D. Reed, and D. Wilson. Satchmore: Satchmo with relevancy. Technical report, Duke Univ., Durham, North Carolina, USA, 1993.  Home/Search   Document Details and Download   Summary   Related Articles   Check

....irrelevant to the query is the major source of inefficiency for bottom up methods. Realizing that, certain approaches utilize a top down component to isolate the relevant clauses of the theory that can contribute to a bottom up search for a refutation of the theory augmented with the query negation[31, 22, 37, 14]. Others employ two cooperating procedures: a top down and bottom up to improve performance [12] The cooperation takes the form of passing intermediate results of one computation to the other. In this paper we offer an alternative method for top down processing of positive queries based on a ....

....approach inherits the termination and efficiency properties of the underlying model generator used for the implementation. We believe that this is a major advantage because of the wealth of information available in the literature on the theory and implementation of model generation procedures [7, 4, 22, 10, 11, 35, 27, 2, 3, 18, 23]. 4 Extensions and Interpretations In this section we discuss relaxing some of the restrictions that were used in the duality approach as presented so far. We try to look at ways to interpret the use of this approach and address some of the cases when this approach can under perform other ....

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D.W. Loveland, D. Reed, and D. Wilson. Satchmore: Satchmo with Relevancy. J. Automated Reasoning, 14:349--363, July 1995.

....rules. By Lemma 12 H(Atoms( B) is a model of S. Hence S is satisfiable. PUHR tableaux are defined for sets of range restricted clauses. Combined with the PUHR expansion rule of Definition 6, the range restriction transformation induces an enumeration of the ground terms, as observed e.g. in [43]. 11 3.2 Comparison of PUHR Tableaux With Related Refutation Methods The PUHR tableaux are a formalization of the principle of the SATCHMO programs, one of them is recalled in the next section. Other formalizations of the SATCHMO approach to theorem proving can be found in [16, 33, 17, 12, 3, ....

....PUHR tableaux are a formalization of the principle of the SATCHMO programs, one of them is recalled in the next section. Other formalizations of the SATCHMO approach to theorem proving can be found in [16, 33, 17, 12, 3, 37, 11, 71] A further more or less implicit formalization is subjacent to [43]. In [71, 11] EP Tableaux are proposed that generalize PUHR Tableaux to nonclausal formulas with restricted quantification . PUHR and hyper tableaux [3, 37] are more in the tableaux style (cf. 66, 25, 73, 74] than the formalizations [16, 33, 17] PUHR tableaux are simpler than hyper tableaux ....

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D. Loveland, D. Reed, and D. Wilson. SATCHMORE: SATCHMO With RElevancy. Jour. of Automated Reasoning, 14, 325--351, 1995.

....applicable to range restricted positive programs, is incorporated in the prover SATCHMO developed by Manthey and Bry [40] SATCHMO is a refutation system that uses Prolog to process the Horn clauses, while acts as a forward chaining prover, simulating hyperresolution, on the non Horn rules. [39] proposes an extension of SATCHMO, called SATCHMORE (standing for SATCHMO with RElevancy) where the set of clauses to 36 be used for forward chaining is significantly reduced by marking relevant literals. In contrast to our algorithm, the above methods [38, 53, 40, 39] are (completely or ....

....on the non Horn rules. 39] proposes an extension of SATCHMO, called SATCHMORE (standing for SATCHMO with RElevancy) where the set of clauses to 36 be used for forward chaining is significantly reduced by marking relevant literals. In contrast to our algorithm, the above methods [38, 53, 40, 39] are (completely or partially) based on a top down computational model. Thus, our algorithm has the well known advantages and drawbacks of bottom up evaluation strategies, while these methods have the advantages and drawbacks of top down strategies. However, it is worth noting that our method is ....

Loveland, D. W., Reed, D. W. and Wilson D. S. (1995), SATCHMORE: SATCHMO with RElevancy, Journal of Automated Reasoning, 14, 325--351.

....expansion rules. By Lemma 12 H(Units( B) is a model of S. Hence S is satisfiable. PUHR tableaux are defined for sets of range restricted clauses. Combined with the PUHR expansion rule of Definition 6, the range restriction transformation induces an enumeration of the ground terms, as observed in [9]. 2.4 Implementation in Prolog The Prolog program of Figure 2 expands fair PUHR tableaux for sets of range restricted clauses in implication form under a depth first search strategy. The tableaux expanded by this program are strict [4] and subsumptionfree. Strictness means that no application of ....

D. Loveland, D. Reed, and D. Wilson. SATCHMORE: SATCHMO with RElevancy. J. Automated Reasoning, Vol. 14, 325--351, 1995.

.... Dank dieser Eigenschaften wurde das Verfahren zur Losung verschiedener Probleme unter anderem zum Entwurf von Datenbankschemata, zur Programmverifikation und synthese [HFF91] zum juristischen Schlie en und zur modellbasierten Diagnose [FN90] angewendet sowie weiterentwickelt [FHKF92, HKF92, Ram91, LRW93]. Die Grundprogramme der SATCHMO Sammlung sind aber oft misverstanden worden, andere Programme sind bisher noch nicht veroffentlicht worden. Ziel dieses Artikels ist es, die Implementierung von bisher nicht veroffentlichen Programmen systematisch zu erlautern, die in Suchstrategien oder ....

Donald W. Loveland, David W. Reed, and Debra S. Wilson. SATCHMORE: SATCHMO with relevancy. Technical report, Dept. of Computer Science, Duke University, 1993.

....expansion rules. By Lemma 12 H(Atoms( B) is a model of S. Hence S is satisfiable. PUHR tableaux are defined for sets of range restricted clauses. Combined with the PUHR expansion rule of Definition 6, the range restriction transformation induces an enumeration of the ground terms, as observed in [17]. 2.4 Implementation in Prolog The Prolog program of Figure 2 expands fair PUHR tableaux for sets of range restricted clauses in implication form under a depth first search strategy. The tableaux expanded by this program are strict [8] and subsumptionfree. Strictness means that no application of ....

D. Loveland, D. Reed, and D. Wilson. SATCHMORE: SATCHMO with RElevancy. J. Automated Reasoning, Vol. 14, 325--351, 1995.

....There are many possible directions for further developments. From a theorem proving perspective, extensions to be investigated and implemented include a more efficient treatment of non range restricted clauses and reasoning with equality [3] In addition, bidirectional search as in SATCHMORE [9] can accelerate proofs of Satchmo. From a logic programming perspective, we would like to support nonmonotonic features such as aggregation and negation as failure, as well as access to predicates defined outside the clausal theory. We would also like to generate all minimal Herbrand models of a ....

D.W. Loveland, D.W. Reed, and D.S. Wilson. SATCHMORE: SATCHMO with RElevancy. Journal of Automated Reasoning, 14:325--351, 1995.

....Science documentation have any selection criterion on which clause should be used when many violated clauses exist. In particular, it would cause combinatorial explosion of the number of model candidates when irrelevant non Horn clauses are selected. Concerning the above problem, SATCHMORE [8] introduces a method called the relevancy testing to avoid redundant model candidate extensions with irrelevant non Horn clauses. The use of the relevancy testing can restrict the selection of violated clauses for model generation to only those all of whose consequent literals are unifiable to ....

....Generation Method In the model generation method, when many violated clauses exist under a model candidate, the number of model candidates and the size of a proof tree change considerably according to the order in which a violated clause is selected. Consider the following clause set given in [8] (SYN009 1 from [19] C 1 : p(c; X;Y ) false: C 2 : q(X; c; Y ) false: C 3 : r(X; Y; c) false: C 4 : true s(a) C 5 : true s(b) C 6 : true s(c) C 7 : s(X) s(Y ) s(Z) p(X; Y; Z) q(X; Y; Z) r(X; Y; Z) When the current model candidate is fs(a) s(b) s(c)g, the last clause C 7 ....

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Loveland, D.W., Reed, D.W. and Wilson, D.S.: SATCHMORE: SATCHMO with RElevancy, J. Automated Reasoning, Vol. 14, No. 2, pp. 325--351 (1995).

.... indicated several possible directions for further developments, but other directions are possible as well: From a theorem proving and model generation perspective, an extension to be investigated and implemented is reasoning with equality [7, 13] In addition, bidirectional search as in Satchmore [15] can accelerate refutation proofs of Satchmo. From a logic programming perspective, we would like to support nonmonotonic features such as aggregation and negation as failure, as well as access to predicates defined outside the clausal theory. From an efficiency perspective, better data structures ....

D. W. Loveland, D. W. Reed, and D. S. Wilson. SATCHMORE: SATCHMO with RElevancy. Journal of Automated Reasoning, 14:325--351, 1995.

....is in the classes of clause sets that the two approaches can handle efficiently. This has suggested a combination of the approaches and has lead to guidelines for the combination. It would be interesting to see if refinements of Satchmo that have been described in the literature (e.g. Satchmore [10] and hyper tableaux [1] can still be combined with the Fermuller Leitsch approach, or if similar refinements can be applied to the latter. The hyper tableaux calculus is a refinement of the PUHR tableaux calculus that performs ground instantiation before splitting steps at runtime on demand ....

D. W. Loveland, D. W. Reed, and D. S. Wilson. SATCHMORE: SATCHMO with RElevancy. Journal of Automated Reasoning, 14:325--351, 1995.

....which do not satisfy the T condition. In [SSI97] we have proposed a pruning method which tries to check on the satisfiability of the T condition as early as possible during the MGTP computation. The proposed method is based on dynamic analysis and uses an idea of relevancy in SATCHMORE[LRW95]. The notion of relevancy of an atom is defined as follows: Definition 3.1 Let 5 be a general logic program and S be a model candidate. Suppose that there exists an atom A T such that: KA T 2 S A T 62 S: 7) Then, an atom A is said to be relevant wrt (S; A T ) if one of the following ....

D.W. Loveland, D.W. Reed, and D.S. Wilson. SATCHMORE: SATCHMO with RElevancy. Automated Reasoning, Vol. 14, pp. 325--351, 1995.

....when a non Horn clause irrelevant to the given goal is selected, many interpretations generated with the clause would become useless. Thus, in the model generation method, it is necessary to develop a method to suppress the generation of useless interpretations. To this end, Loveland et al. [6] proposed a method to impose a strong restriction on selecting a violated clause to say that no clause need be selected unless all the consequent literals are relevant (be totally relevant ) In the sequel, we simply call it relevancy testing to check if a clause is totally relevant. The ....

....above, the relevancy testing and the NHM methods have been presented to prevent redundant interpretations from being generated by SATCHMO and MGTP. However, the relationship between both methods has not yet been clarified. According to several experimental results having been obtained so far [6, 4], it is estimated that relevancy testing and NHM have the same pruning ability. In this paper, we define the concept of weak relevancy testing that mitigates the condition of relevancy testing [6] and analyze the relationship between the weak relevancy testing and the NHM methods. Then, we prove ....

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Loveland, D. W., Reed, D. and Wilson, D. S., SATCHMORE: SATCHMO with RElevancy, J. Automated Reasoning, 14(2):325--351, 1995.

....traditional bottom up processing for the class of positive queries against a disjunctive database. 1 Introduction Model generation received much attention in the literature both as a basis for refutation procedures and to generate model representations for logic programs under different semantics [17, 9, 16, 26]. Several efficient implementations were reported in the literature that can serve as a basis for (minimal) model based reasoning [5, 11, 20] Current work is directed at introducing enhancements to get more general systems in terms of the class of theories being treated. Model generation is ....

D.W. Loveland, D. Reed, and D. Wilson. Satchmore: Satchmo with relevancy. J. Automated Reasoning, 14:349--363, July 1995.

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) D.W. Loveland, D. Reed, and D. Wilson. SATCHMORE: SATCHMO with RElevancy. J. Automated Reasoning, 14:349--363, July 1995.

No context found.

D. Loveland, D. Reed, and D. Wilson. Satchmore: Satchmo with relevancy. Technical report, Duke Univ., Durham, North Carolina, USA, 1993.

No context found.

D.W. Loveland, D. Reed, and D. Wilson. Satchmore: Satchmo with relevancy. J. Automated Reasoning, 14:349--363, July 1995.

No context found.

D. W. Loveland, D. W. Reed, and D. S. Wilson. SATCHMORE: SATCHMO with RElevancy. J. of Automated Reasoning, 14, 325--351, 1995.

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