In this paper, a method to divide a large-scale logic program is proposed. The hierarchical structure of the given logic program can be found by using graph theory. An Illustrative example of elevator control program ...
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ISBN:
(纸本)9780780387300
In this paper, a method to divide a large-scale logic program is proposed. The hierarchical structure of the given logic program can be found by using graph theory. An Illustrative example of elevator control program is shown as application of the proposed theory.
Total correctness assertions (TCAs) have long been considered a natural formalization of successful program termination. However, research dating back to the 1980s suggests that validity of TCAs is a notion of limited...
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ISBN:
(纸本)0769521924
Total correctness assertions (TCAs) have long been considered a natural formalization of successful program termination. However, research dating back to the 1980s suggests that validity of TCAs is a notion of limited interest;we corroborate this by proving compactness and Herbrand properties for the valid TCAs, defining in passing a new sound, complete, and syntax-directed deductive system for TCAs. It follows that proving TCAs whose truth depends on underlying inductive data-types is impossible in logics of programs that are sound for all structures, such as Dynamic logic based on Segerberg's PDL, even when augmented with powerful first-order theories like Peano Arithmetic. Harel's Convergence Rule bypasses this difficulty, but is methodologically and conceptually problematic, in addition to being unsound for general validity. We propose instead to bind variables to inductive data via DL's box operator, leading to an alternative formalization of termination assertions, which we dub Inductive TCA (ITCA). We observe that a TCA is provable in Harel's DL exactly when the corresponding ITCA is provable in Segerbegs's DL, thereby showing that the Convergence Rule is not foundationally or practically necessary. We also show that validity of ITCAs is directly reducible to validity of partial correctness assertions, confirming the foundational importance of the latter.
Description logics (DLs) theoretically explore knowledge representation and its reasoning in concept languages. However, due to the concept-oriented notion, these logics are not equipped with rule-based reasoning mech...
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ISBN:
(纸本)0889864047
Description logics (DLs) theoretically explore knowledge representation and its reasoning in concept languages. However, due to the concept-oriented notion, these logics are not equipped with rule-based reasoning mechanisms for assertional knowledge bases;specifically, rules and facts in logic programming, or the interaction of rules and facts with terminology. In order to deal with the enriched reasoning, this paper presents a hybrid reasoning system for combining DL-knowledge bases (TBox and ABox) and first-order clause sets. The main result of this study is that a sound and complete resolution method for the composed knowledge bases is designed, and it has the feature of an effective deduction procedure such as Robinson's resolution principle.
In Semantic Web, using rules to add more expressive power has drawn considerable attention. Recently ORL (OWL Rules Language) has been presented where OWL is extended with Horn clause rules. In this paper we propose a...
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ISBN:
(纸本)3540238425
In Semantic Web, using rules to add more expressive power has drawn considerable attention. Recently ORL (OWL Rules Language) has been presented where OWL is extended with Horn clause rules. In this paper we propose an extension to OWL with more general rules involving not only atoms but also literals with classical negation and negation as failure. We present first the abstract syntax for our OWL extension and then its semantics via the Answer Set programming(ASP). Furthermore, we discuss the iterative procedures for reasoning between OWL axioms and ASP rules.
In this paper, we study how a logical form of scientific modelling that integrates together abduction and induction can be used to understand the functional class of unknown enzymes or inhibitors. We show how we can m...
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ISBN:
(纸本)3540229418
In this paper, we study how a logical form of scientific modelling that integrates together abduction and induction can be used to understand the functional class of unknown enzymes or inhibitors. We show how we can model, within Abductive logic programming (ALP), inhibition in metabolic pathways and use abduction to generate facts about inhibition of enzymes by a particular toxin (e.g. Hydrazine) given the underlying metabolic pathway and observations about the concentration of metabolites. These ground facts, together with biochemical background information, can then be generalised by ILP to generate rules about the inhibition by Hydrazine thus enriching further our model. In particular, using Progol 5.0 where the processes of abduction and inductive generalization are integrated enables us to learn such general rules. Experimental results on modelling in this way the effect of Hydrazine in a real metabolic pathway are presented.
This paper defines a general framework for testing equivalence of logic programs with respect to two parameters. Given two sets of rules Q and R, two logic programs P-1 and P-2 are said to be update equivalent with re...
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ISBN:
(数字)9783540302278
ISBN:
(纸本)3540232427
This paper defines a general framework for testing equivalence of logic programs with respect to two parameters. Given two sets of rules Q and R, two logic programs P-1 and P-2 are said to be update equivalent with respect to (Q, R) if (P-1 \ Q) boolean OR R and (P-2 \ Q) boolean OR R have the same answer sets for any two logic programs Q subset of or equal to Q and R subset of or equal to R. The notion of update equivalence is suitable to take program updates into account when two logic programs are compared. That is, the notion of relativity stipulates the languages of updates, and two parameters Q and R correspond to the languages for deletion and addition, respectively. Clearly, the notion of strong equivalence is a special case of update equivalence where Q is empty and R is the set of all rules in the language. In fact, the notion of update equivalence is strong enough to capture many other notions such as weak equivalence, update equivalence on common rules, and uniform equivalence. We also discuss computation and complexity of update equivalence.
The paper describes the experiences of teaching a constraint logic programming course at the Budapest University of Technology and Economics. We describe the structure of the course, the material covered, some example...
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ISBN:
(纸本)3540218343
The paper describes the experiences of teaching a constraint logic programming course at the Budapest University of Technology and Economics. We describe the structure of the course, the material covered, some examples, assignments, and examination tasks. Throughout the paper we show how logic puzzles can be used to illustrate constraint programming techniques.
We describe the MyYapDB, a deductive database system coupling the Yap Prolog compiler and the MySQL DBMS. We use our OPTYap extension of the Yap compiler, which is the first available system that can exploit paralleli...
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ISBN:
(数字)9783540302278
ISBN:
(纸本)3540232427
We describe the MyYapDB, a deductive database system coupling the Yap Prolog compiler and the MySQL DBMS. We use our OPTYap extension of the Yap compiler, which is the first available system that can exploit parallelism from tabled logic programs. We describe the major features of the system, give a simplified description of the implementation and present a performance comparison of using static facts or accessing the facts as MySQL tuples for a simple example.
Well-known principles of induction include monotone induction and different sorts of non-monotone induction such as inflationary induction, induction over well-ordered sets and iterated induction. In this work, we def...
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ISBN:
(纸本)354020721X
Well-known principles of induction include monotone induction and different sorts of non-monotone induction such as inflationary induction, induction over well-ordered sets and iterated induction. In this work, we define a logic formalizing induction over well-ordered sets and monotone and iterated induction. Just as the principle of positive induction has been formalized in FO(LFP), and the principle of inflationary induction has been formalized in FO(IFP), this paper formalizes the principle of iterated induction in a new logic for Non-Monotone Inductive Definitions (NMID-logic). The semantics of the logic is strongly influenced by the well-founded semantics of logic programming. Our main result concerns the modularity properties of inductive definitions in NMID-logic. Specifically, we formulate conditions under which a simultaneous definition Delta of several relations is logically equivalent to a conjunction of smaller definitions Delta(1) boolean AND . . . boolean AND Delta(n) with disjoint sets of defined predicates. The difficulty of the result comes from the fact that predicates P-i and P-j defined in Delta(i) and Delta(j), respectively, may be mutually connected by simultaneous induction. Since logic programming and abductive logic programming under well-founded semantics are proper fragments of our logic, our modularity results are applicable there as well. As an example of application of our logic and theorems presented in this paper, we describe a temporal formalism, the inductive situation calculus, where causal dependencies axe naturally represented as rules of inductive definitions.
This paper describes OLEX, a prototypical system for text classification. The main characteristics of OLEX are: using ontologies for the formal representation of the domain knowledge-, employing the pre-processing tec...
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ISBN:
(数字)9783540302278
ISBN:
(纸本)3540232427
This paper describes OLEX, a prototypical system for text classification. The main characteristics of OLEX are: using ontologies for the formal representation of the domain knowledge-, employing the pre-processing technologies for a symbolic representation of text features;exploiting the expressive power of logic programming to extract concepts from documents. The proposed approach allows us to perform a high-precision document classification.
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