Denecker, M., Schreye, D.D.: SLDNFA: An abductive procedure for normal abductive programs. In Apt, K., ed.: Proceedings of the Joint International Conference and Symposium on Logic Programming, Cambridge, MIT Press (1992) 686--702  Home/Search   Document Details and Download   Summary   Related Articles   Check

....follows the treatment given in [KR98] Abductive Concept Learning is an extension of ILP that allows us to represent both the background and target theories as abductive logic programs. Indeed abduction is well suited for representing problems with incomplete information (see e.g. PGA87, KM90b, DDS92, Ino94, IS94, KKT97] able to formulate a variety of such problems in Artificial Intelligence and other areas of Computer Science. Abductive logic programs are composed of a logic program, a set of abducible predicates and a set of integrity constraints that provide additional information on the ....

....the next sections, in the Abductive Concept Learning framework and system, deductive entailment is replaced by the abductive entailment as the coverage relation. Thus the deductive SLD (and SLDNF) proof procedures of Logic Programming are replaced by abductive proof procedures [EK89, KM90a, KM90c, DDS92, SI92] of ALP. Any abductive procedure satisfying the following notion of abductive derivability is suitable. Definition 39 (Abductive derivability) Given an abductive theory T = hP; A; Ii, a goal G and an initial strong abductive explanation Delta i , we say that a procedure abductively ....

M. Denecker and D. De Schreye. SLDNFA: an abductive procedure for normal abductive programs. In K. R. Apt, editor, Proceedings of the International Joint Conference and Symposium on Logic Programming, pages 686--700, 1992.

....each answer set is taken as a solution to a given problem, loop handling becomes a semantic issue a sound and complete backward chaining procedure cannot be defined without it. A number of abductive procedures have been proposed for the two valued as well as three valued completion semantics [3, 4, 9], of which the system by Console et al. 3] and the IFF procedure by Fung and Kowalski [9] also use rewriting as the main mechanism to compute explanations. Console et al. show that, for non recursive programs (called hierarchical programs) abductive explanations can be computed as a deduction by ....

....can be computed as a deduction by rewriting using iff definitions. Fung and Kowalski extend this idea to the class of all normal programs, and get completeness results that can be stated without resorting to termination. This improves the completeness theorems by Denecker and De Schreye [4] which rely on termination as a condition. All of these procedures are defined for cautious reasoning computing bindings for which an (existential) goal is true in all indented models. In our case the reasoning mode is brave establishing whether a query is true in one of the intended models. ....

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M. Denecker and D. De Schreye. SLDNFA: an abductive procedure for normal abductive programs. J. Logic Programming, 34(2):111--167, 1998.

....St. Nicosia, Cyprus antonis ucy.ac. cy 1 General Information The A system [4] is a new system for performing abductive reasoning within the framework of Abductive Logic Programming (ALP) The principles behind the system are founded by work on two earlier systems ACLP [2, 3] and SLDNFA(C) [1, 6]. The basic inference mechanism of the system combines abductive logic programming and constraint logic programming. In its computation it reduces the high level speci cation of the problem and goal at hand to a lower level constraint store. This constraint store is managed by an ecient ....

Marc Denecker and Danny De Schreye. SLDNFA: an abductive procedure for normal abductive programs. J. Logic Programming, 34(2):111-167, 1998.

....NEC, we derive conditional conclusions of the form holdsAt(p, t) 3 E2 [ happens(E2) terminates(E2, p) e E2 E2 t] The proof procedure in [6] allows unconditional holdsAt conclusions to be derived by retrospectively completing the input. The proof procedure of Denecker and De Schreye [3] seems to give similar results. 8 Conclusions We believe that the theorems presented in this paper help to explain why simplified forms of the event calculus have gradually replaced the original event calculus in practice. We believe that they also demonstrate the more general potential ....

Denecker M. and De Schreye D., "SLDNFA: an abductive procedure for normal abductive programs", Proceedings of International Conference and Symposium on Logic Programming, 1992, 686-700.

....extending early work in [29] for constructive negation through abduction which in turn was based on the work of [14] for NAF through abduction. Recent work on constructive abduction in Logic Programming can be found in [7, 15, 55] The abductive proof procedure SLDNFA of Denecker and De Schreye [6, 7] incorporates abduction and negation as failure for the treatment of non ground abductive goals in normal abductive programs. SLDNFA is an extension of the SLDNF procedure for the cases where an abducible atom is selected in a positive or negative goal. The case where an abducible atom is selected ....

....skolemization. This procedure is sound and complete wrt a three valued completion semantics for abductive logic programs. The Iff proof procedure of Fung and Kowalski [15] can be regarded as a hybrid of the proof procedure of Console et al. 3] and the SLDNFA procedure of Denecker and De Schreye [6, 7]. In comparison with SLDNFA the Iff procedure has several differences some of which are the following. The predicates in this procedure are defined in if and only if form, it uses explicit rewrite rules for equality, instead of extending unification, and avoids skolemization by using existential ....

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M.Denecker and D.De Schreye. SLDNFA: an abductive procedure for normal abductive programs. Proc. International Conference and Symposium on Logic Programming, 686-700, 1992.

....procedure cannot be defined without it. Thus, a distinct feature of our work is a mechanism of loop handling both for termination and for the implementation of the underlying semantics. Completed programs have been used in query answering in abstract, abductive procedures in [Console et al. 1991; Denecker and Schreye, 1998; Fung and Kowalski, 1997] for non ground programs with constraints. These procedures are defined for the three valued completion semantics under the certainty mode of reasoning computing bindings for which an (existential) goal is true in all indented models. In our case the reasoning mode is ....

M. Denecker and D. De Schreye. Sldnfa: an abductive procedure for normal abductive programs. J. Logic Programming, 34(2):111--167, 1998.

....rst copying algorithm, and depending on the order in which root pointers are treated. Sliding has no such non determinism: once marking is done, there is only one possible new heap. Clearly, Prolog is not a good language to express such non determinism. In an abductive setting (see for instance [10]) one can specify the relation between the old and the new heap, without a speci cation of how this relation is to be realized. Moreover, the natural setting is by making the heap after collection an abducible (also called open) predicate, say new heap 3. Also the correspondence between the heap ....

M. Denecker, and D. De Schreye. SLDNFA: an abductive procedure for normal abductive programs J. Logic Programming 34 (1998), no. 2, 111-167.

....procedure cannot be defined without it. Thus, a distinct feature of our work is a mechanism of loop handling both for termination and for the implementation of the underlying semantics. Completed programs have been used in query answering in abstract, abductive procedures in [Console et al. 1991; Denecker and Schreye, 1998; Fung and Kowalski, 1997] for non ground programs with constraints. These procedures are defined for the three valued completion semantics under the certainty mode of reasoning computing bindings for which an (existential) goal is true in all indented models. In our case the reasoning mode is ....

M. Denecker and D. De Schreye. Sldnfa: an abductive procedure for normal abductive programs. J. Logic Programming, 34(2):111--167, 1998.

....explained in simple terms as follows: Given a background knowledge A B and an observation A, the problem of abduction is to explain how A could be true. This reasoning will infer B as a possible explanation for A. Abductive procedures to carry out such reasoning have also been studied in detail [DS95, for example]. Suppose there is an additional clause A C, this reasoning might lead to an indefinite explanation B C for A. In this sense, abductive reasoning leads to indefinite conclusions and is comparable with disjunctive logic programming. This relationship has been studied by works like [SI94] that ....

Marc Denecker and Danny De Schreye. Sldnfa: an abductive procedure for normal abductive programs. Technical report, Department of Computer Science, K. U. Leuven, Belgium, 1995.

....Iwayama [23] proposed a query based proof procedure which improves Kakas and Mancarella s one, and addresses completeness with generalized stable model semantics [13] but at the expense of a more complex integrity checking. Another proof procedure has been proposed by Denecker and De Schreye in [8], by extending the SLDNF resolution to the case of abduction. A crucial property of this abductive procedure is the treatment of non ground abductive goals considered neither in [14] nor in our abductive protocol. In [8] the authors do not consider general integrity constraints, but only ....

....Another proof procedure has been proposed by Denecker and De Schreye in [8] by extending the SLDNF resolution to the case of abduction. A crucial property of this abductive procedure is the treatment of non ground abductive goals considered neither in [14] nor in our abductive protocol. In [8], the authors do not consider general integrity constraints, but only constraints of the kind a; not a. To overcome this limitation, in a later work [9] they consider the treatment of general integrity constraints that are checked only at the end of the proof for a query, i.e. only when the ....

M. Denecker and D. De Schreye. SLDNFA: an abductive procedure for normal abductive programs. In K. Apt, editor, Proc. Int. Joint Conf. and Symp. on Logic Programming, pages 686--700. The MIT Press, 1992.

....the time points T 1 and T 2 . If the time points in the clipped predicate are not ground, it is necessary to use constructive negation. The constructive negation technique in the present paper is adapted from the iff procedure [ Fung, 1996; Fung and Kowalski, 1998 ] and the recent version [ Denecker and Schreye, 1998 ] of SLDNFA [ Denecker and Schreye, 1992 ] The derivation rules ab6, ab7, ab8, ab9, co6, co7, co8, co9, co10, co11, to be introduced, are adapted from the rewrite rules of Martelli and Montanari [ Martelli and Montanari, 1982 ] for equations as in the iff procedure. The approach to handling ....

M. Denecker and D. D. Schreye. SLDNFA: an abductive procedure for normal abductive programs. Logic Programming, 34(2):111-- 167, 1998.

....time points in the clipped predicate are not ground, it is necessary to use constructive negation. The constructive negation technique in the present paper is adapted from the iff procedure [ Fung, 1996; Fung and Kowalski, 1998 ] and the recent version [ Denecker and Schreye, 1998 ] of SLDNFA [ Denecker and Schreye, 1992 ] The derivation rules ab6, ab7, ab8, ab9, co6, co7, co8, co9, co10, co11, to be introduced, are adapted from the rewrite rules of Martelli and Montanari [ Martelli and Montanari, 1982 ] for equations as in the iff procedure. The approach to handling constraints is different from the iff ....

M. Denecker and D. D. Schreye. SLDNFA: an abductive procedure for normal abductive programs. In the joint international conference and symposium on logic programming, pages 686--700, 1992.

....in [26] to express negative information, and it has been later recognized as a suitable form of non monotonic reasoning. For instance, negation as failure provides a simple and elegant solution to the well known frame problem in AI, as exemplified by the so called Yale Shooting Problem [13, 31, 43]. More recently, other extensions have been proposed to further enrich the expressive power of LP in order to turn it into a general formalism for knowledge representation (for a survey, see [15] Among others, we mention abductive LP [42, 35, 48] and LP with different forms of negation (e.g. ....

....implemented semantics does not always give the intuitive expected results. This semantics does not guarantee the global non56 contradictoriness (which is, instead, guaranteed in our proof procedure) since considered too complex to be tested, but only some form of local non contradictoriness. In [31], Denecker and De Schreye introduce a proof procedure for normal abductive logic programs by extending the SLDNF resolution to the case of abduction. The resulting proof procedure (SLDNFA) is correct with respect to the completion semantics. A crucial property of this abductive procedure is the ....

[Article contains additional citation context not shown here]

M. Denecker, and D. De Schreye. SLDNFA: an abductive procedure for normal abductive programs. In K. Apt, editor, Proc. Int. Joint Conf. and Symp. on Logic Programming, pages 686--700. The MIT Press, 1992.

....as Reiter s unique name axioms. negation is not used, then the WFSX semantics coincides with the WFS semantics. Since we only use acyclic normal logic programs, the use of REVISE is not essential for the purpose of this paper, and other abductive query evaluation procedures such as those in [DdS 92, SI 92] for abductive normal logic programs can also be used. In what follows we introduce three techniques to improve search efficiency. Proposition 4.10 Let D be a consistent domain description, H a history, and N = holds(Fn ; Tn ) new knowledge to be assimilated. Then, for any abductive ....

....system for logic programs with the WFSX semantics [PAA 93] Although our examples are simple and small sized, it looks that our methodology works well. We should point out that our methodolgy can be experimented with any other abductive normal logic programming systems such as those based on [DdS 92, SI 92] 5 Related work There has been much work in belief revision and update. In the AGM theory [Gar 88] eight postulates are proposed for belief revision. Katsuno and Mendelzon [KatM 91] made a distinction between the belief revision in static domains and belief update in dynamic domains, ....

Denecker, M., De Schreye, D., SLDNFA: an abductive procedure for normal abductive programs, in K. R. Apt (ed.), Logic Programming: Proc. of 1992 Int'l Joint Conference and Symposium, 1992, 686-700

....complexity results of Sections 3.1 and 3.2. Furthermore, Abdual evaluations are confluent in the sense that Theorem 3.1 holds for any ordering of applicable Abdual operations. The complexity and termination for WFS distinguishes Abdual from approaches such as the IFF proof procedure [9] and SLDNFA [6]. These approaches do allow variables in rules which Abdual does not. The methods of [3] and [10] compute abductive explanation based on some form of two valued rule completion for non abducible predicates (the former based on Clark s completion, and the latter based on the so called transaction ....

M. Denecker and D. De Schreye. SLDNFA: An abductive procedure for normal abductive programs. In JICSLP, pages 868--700. MIT Press, 1992.

.... the predicate completion semantics coincides with other semantics such as the stable model semantics [22] and the wellfounded model semantics [70] In the case of abductive logic programs, the semantical coincidence still holds, as shown by Denecker [16] There have been many proposals, e.g. [15, 65], for abductive query evaluation procedures for abductive normal logic programs. The work reported in this paper has been experimented with the latest version of the REVISE system [13] an extended logic programming system for revising knowledge bases. It is based on logic programming with ....

Denecker, M., De Schreye, D., SLDNFA: an abductive procedure for normal abductive programs, Logic Programming: Proc. of 1992 Int'l Joint Conference and Symposium, . Apt, ed., MIT Press, 1992, 686-700

....in AC to abductive query evaluaiton in logic program D. The work reported in this paper has been experimented with the latest version of the REVISE system [5] The use of the REVISE system is not essential, and other abductive query evaluaiton procedures for normal logic programs such as SLDNFA [6] and that in [23] should also work. If for every fluent name F , one and only one of initially F and initially :F appears in a domain description, then PROLOG can be used for temporal projection after (3) 4) and (6) are removed and the integrity constraitns are represented only in the form of ....

Denecker, M., De Schreye, D., SLDNFA: an abductive procedure for normal abductive programs, Logic Programming: Proc. of 1992 Int'l Joint Conference and Symposium, . Apt, ed., MIT Press, 1992, 686-700

....subset satisfying the above two conditions. Note that COMP (P ; A) I[fbg is not consistent. Thus, fbg is not an abductive answer to p in FOO. Now suppose that we want to evaluate a query q. It can be shown that there is no abductive answer to it. There have been many proposals, e.g. [11, 30], for abductive query evaluation procedures for abductive normal logic programs. The work reported in this paper has been experimented with the latest version of the REVISE system [9] an extended logic programming system for revising knowledge bases. It is based on 2 Let P be a normal logic ....

....in ACto abductive query evaluaiton in logic program D. The work reported in this paper has been experimented with the latest version of the REVISE system [9] The use of the REVISE system is not essential, and other abductive query evaluaiton procedures for normal logic programs such as SLDNFA [11] and that in [30] should also work. If for every fluent name F , one and only one of initially F and initially :F appears in a domain description, then PROLOG can be used for temporal projection after (3) 4) and (6) are removed and the integrity constraitns are represented only in the form of ....

M. Denecker and D. De Schreye. SLDNFA: an abductive procedure for normal abductive programs. In K. R. Apt, editor, Logic Programming: Proc. of 1992 Int'l Joint Conference and Symposium, pages 686--700. MIT Press, 1992.

No context found.

M. Denecker and D. De Schreye. SLDNFA: an abductive procedure for normal abductive programs. Journal of Logic Programming, 34, 1998.

....task is deduction: Given a query Q (with Q a conjunction of literals) the task is to find a substitution a such that Qa is true in the unique model of the program. The Asystem [13, 1] is able to combine both computational tasks, because it is an implementation of the SLDNFA procedure [9]. That SLDNFA procedure 5 This is exactly the least Herbrand model in the case of a definite program. is a sound and complete abductire extension of the SLDNF procedure that is at the basis of any implementation of logic programming. Given an ID Logic theory (Z) r) and a query 4 Q, SLDNFA ....

Marc Denecker and Danny De Schreye. SLDNFA: an abductive procedure for normal abductive programs. Journal of Logic Programming, 34(2):111-167, February 1998.

....database repairs in terms of a certain set of models of the inconsistent database (those that, intuitively, minimize the amount of inconsistent information) The other approach is based on abductive reasoning. For this we use an abductive solver (A system, 27] that implements SLDNFA resolution [16, 17] for computing a list of data facts that should be inserted to the database or retracted from it in order to keep the data consistent. A corresponding application was introduced and described in greater details in [7] Here we review it in order to keep this paper self contained, and putting our ....

M.Denecker, D.De Schreye. SLDNFA an abductive procedure for normal abductive programs. Proc. Int. Joint Conf. and Symp. on Logic Programming , pp.686-700, MIT Press, 1992.

No context found.

Denecker, M., Schreye, D.D.: SLDNFA: An abductive procedure for normal abductive programs. In Apt, K., ed.: Proceedings of the Joint International Conference and Symposium on Logic Programming, Cambridge, MIT Press (1992) 686--702

No context found.

M. Denecker and D. D. Schreye. SLDNFA: an abductive procedure for normal abductive programs. In K. Apt, editor, IJCSLP'92, pages 686--700. MIT Press.

No context found.

) M. Denecker and D. De Schreye. SLDNFA: an abductive procedure for normal abductive programs. In K. R. Apt, editor, Proceedings of the International Joint Conference and Symposium on Logic Programming, pages 686--700, 1992.

No context found.

Marc Denecker and Danny De Schreye, `Sldnfa: an abductive procedure for normal abductive programs', Technical report, Department of Computer Science, K. U. Leuven, Belgium, (1995).

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