In this paper we develop a concept aware multi-preferential semantics for dealing with typicality in description logics, where preferences are associated with concepts, starting from a collection of ranked TBoxes cont...
详细信息
In this paper we develop a concept aware multi-preferential semantics for dealing with typicality in description logics, where preferences are associated with concepts, starting from a collection of ranked TBoxes containing defeasible concept inclusions. Preferences are combined to define a preferential interpretation in which defeasible inclusions can be evaluated. the construction of the concept-aware multipreference semantics is related to Brewka's framework for qualitative preferences. We exploit Answer Set programming (in particular, asprin) to achieve defeasible reasoning under the multipreference approach for the lightweight description logic EL perpendicular to+
We introduce a declarative approach for a coherent composition of autonomous databases. For this we use ID-logic, a formalism that extends classical logic with inductive definitions. We consider ID-logictheories that...
详细信息
ISBN:
(纸本)3540285385
We introduce a declarative approach for a coherent composition of autonomous databases. For this we use ID-logic, a formalism that extends classical logic with inductive definitions. We consider ID-logictheories that express, at the same time, the two basic challenges in database composition problems: relating different schemas of the local databases to one global schema (schema integration) and amalgamating the distributed and possibly contradictory data to one consistent database (data integration). We show that our framework supports different methods for schema integration (as well as their combinations) and that it provides a straightforward way of dealing with inconsistent data. Moreover, this framework facilitates the implementation of database repair and consistent query answering by means of a variety of reasoning systems.
We introduce the logic-based planning language K-c as an extension of K [5]. K-c has two advantages upon K. First, the introduction of external function calls in the rules of a planning description allows the knowledg...
详细信息
ISBN:
(纸本)9783540721994
We introduce the logic-based planning language K-c as an extension of K [5]. K-c has two advantages upon K. First, the introduction of external function calls in the rules of a planning description allows the knowledge engineer to describe certain planning domains, e.g. involving complex action effects, in a more intuitive fashion then is possible in K. Secondly, in contrast to the conformant planning framework K, K-c is formalized as a conditional planning system, which enables K-c to solve planning problems that are impossible to express in K, e.g. involving sensing actions. A prototype implementation of conditional planning with K-c is build on top of the DLVK system, and we illustrate its use by some small examples.
We consider random logic programs with two-literal rules and study their properties. In particular, we obtain results on the probability that random "sparse" and "dense" programs with two-literal r...
详细信息
ISBN:
(纸本)9783642042379
We consider random logic programs with two-literal rules and study their properties. In particular, we obtain results on the probability that random "sparse" and "dense" programs with two-literal rules have answer sets. We study experimentally how hard it is to compute answer sets of such programs. For programs that are constraint-free and purely negative we show that the easy-hard-easy pattern emerges. We provide arguments to explain that behavior. We also show that the hardness of programs from the hard region grows quickly withthe number of atoms. Our results point to the importance of purely negative constraint-free programs for the development of ASP solvers.
Matchmaking is a form of scheduling that aims at bringing companies or people together that share common interests, services, or products in order to facilitate future business partnerships. We begin by furnishing a f...
详细信息
ISBN:
(纸本)9783642405648
Matchmaking is a form of scheduling that aims at bringing companies or people together that share common interests, services, or products in order to facilitate future business partnerships. We begin by furnishing a formal characterization of the corresponding multi-criteria optimization problem. We then address this problem by Answer Set programming in order to solve real-world matchmaking instances, which were previously dealt with by special-purpose algorithms.
Magic sets are a Datalog to Datalog rewriting technique to optimize query answering. the rewritten program focuses on a portion of the stable model(s) of the input program which is sufficient to answer the given query...
详细信息
Magic sets are a Datalog to Datalog rewriting technique to optimize query answering. the rewritten program focuses on a portion of the stable model(s) of the input program which is sufficient to answer the given query. However, the rewriting may introduce new recursive definitions, which can involve even negation and aggregations, and may slow down program evaluation. this paper enhances the magic set technique by preventing the creation of (new) recursive definitions in the rewritten program. It turns out that the new version of magic sets is closed for Datalog programs with stratified negation and aggregations, which is very convenient to obtain efficient computation of the stable model of the rewritten program. Moreover, the rewritten program is further optimized by the elimination of subsumed rules and by the efficient handling of the cases where binding propagation is lost. the research was stimulated by a challenge on the exploitation of Datalog/DLV for efficient reasoning on large ontologies. All proposed techniques have been hence implemented in the DLV system, and tested for ontological reasoning, confirming their effectiveness.
the logic FO(ID) uses ideas from the field of logicprogramming to extend first order logic with non-monotone inductive definitions. the goal of this paper is to extend Gentzen's sequeut calculus to obtain a deduc...
详细信息
ISBN:
(纸本)9783642042379
the logic FO(ID) uses ideas from the field of logicprogramming to extend first order logic with non-monotone inductive definitions. the goal of this paper is to extend Gentzen's sequeut calculus to obtain a deductive inference method for FO(ID). the main difficulty in building Such a proof system is the representation and inference of unfounded sets. It turns out that we can represent unfounded sets by least fixpoint expressions borrowed from stratified least fixpoint logic (SLFP), which is a logic with a least fixpoint operator and characterizes the expressibility of stratified logic programs. therefore, in this paper, we integrate least fixpoint expressions into FO(ID) and define the logic FO(ID,SLFP). We investigate a sequeut calculus for FO(ID,SLFP), which extends the sequent calculus for SLFP with inference rules for the inductive definitions of FO(ID). We show that this proof system is sound with respect to a slightly restricted fragment of FO(ID) and complete for a more restricted fragment of FO(ID).
Answer Set programming (ASP) is a truly-declarative programming paradigm proposed in the area of non-monotonic reasoning and logicprogramming. In the last few years, several tools for ASP-program development have bee...
详细信息
ISBN:
(纸本)9783642208942;9783642208959
Answer Set programming (ASP) is a truly-declarative programming paradigm proposed in the area of non-monotonic reasoning and logicprogramming. In the last few years, several tools for ASP-program development have been proposed, including (more or less advanced) editors and debuggers. However, ASP still lacks an Integrated Development Environment (IDE) supporting the entire life-cycle of ASP development, from (assisted) programs editing to application deployment. In this paper we present ASPIDE, a comprehensive IDE for ASP, integrating a cutting-edge editing tool (featuring dynamic syntax highlighting, on-line syntax correction, autocompletion, code-templates, quick-fixes, refactoring, etc.) with a collection of user-friendly graphical tools for program composition, debugging, profiling, database access, solver execution configuration and output-handling.
We present a logical framework allowing us to express assessment of facts (is it proven?) and arguments (is it sound?) together with a proof system to answer these questions. Our motivation is to clarify the notion of...
详细信息
ISBN:
(纸本)9783030205287;9783030205270
We present a logical framework allowing us to express assessment of facts (is it proven?) and arguments (is it sound?) together with a proof system to answer these questions. Our motivation is to clarify the notion of validity in the context of logic-based arguments along different aspects (such as the formulas used and the inference scheme). Originality lies in the possibility for the user to design their own argument schemes. We show that classical inference obtains when arguments are based on classical schemes (e.g. Hilbert axioms). We go beyond classical logic by distinguishing "proven" formulas from "uncontroversial" ones (whose negation is not proven). Hence a formal definition of a fallacious argument: it uses controversial formulas or schemes recognized as illicit. We express some rational arguments and fallacies in the form of schemes.
We present a logicprogramming based conditional planner that is capable of generating both conditional plans and conformant plans in the presence of sensing actions and incomplete information. We prove the correctnes...
详细信息
暂无评论