Order and Negation as Failure
نویسندگان
چکیده
We equip ordered logic programs with negation as failure, using a simple generalization of the preferred answer set semantics for ordered programs. This extension supports a convenient formulation of certain problems, which is illustrated by means of an intuitive simulation of logic programming with ordered disjunction. The simulation also supports a broader application of “ordered disjunction”, handling problems that would be cumbersome to express using ordered disjunction logic programs. Interestingly, allowing negation as failure in ordered logic programs does not yield any extra computational power: the combination of negation as failure and order can be simulated using order (and true negation) alone.
منابع مشابه
Minimal Belief and Negation as Failure: A Feasible Approach
Lifschitz introduced a logic of minimal belief and negation as failure, called MBNF, in order to provide a theory of epistemic queries to nonmonotonic databases. We present a feasible subsystem of MBNF which can be translated into a logic built on first order logic and negation as failure, called FONF. We give a semantics for FONF along with an extended connection calculus. In particular, we de...
متن کاملSystem Description: KRHyper
KRHyper is a first order logic theorem proving and model generation system based on the hyper tableau calculus. It is targeted for use as an embedded system within knowledge based applications. In contrast to most first order theorem provers, it supports features important for those applications, for example queries with predicate extensions as answers, handling of large sets of uniformly struc...
متن کاملSupporting Open and Closed World Reasoning on the Web
In this paper general mechanisms and syntactic restrictions are explored in order to specify and merge rule bases in the Semantic Web. Rule bases are expressed by extended logic programs having two forms of negation, namely strong (or explicit) and weak (also known as default negation or negation-as-failure). The proposed mechanisms are defined by very simple modular program transformations, an...
متن کاملCompiling Intensional Sets in CLP
Constructive negation has been proved to be a valid alternative to negation as failure, especially when negation is required to have, in a sense, an ‘active’ role. In this paper we analyze an extension of the original constructive negation in order to gracefully integrate with the management of set-constraints in the context of a Constraint Logic Programming Language dealing with finite sets. W...
متن کاملOn the Complexity of Reasoning with Negation as Failure
In this work we study the computational properties of the propositional fragment of MBNF , the logic of minimal belief and negation as failure introduced by Lifschitz, which can be considered as a unifying framework for several nonmonotonic formalisms. In particular, the logic MBNF has been used in order to give a declarative semantics to very general classes of logic programs with negation. We...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
عنوان ژورنال:
دوره شماره
صفحات -
تاریخ انتشار 2003