1. |
- Andersson, Robin, et al.
(författare)
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RoSy : A Rough Knowledge Base System
- 2005
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Ingår i: Rough Sets, Fuzzy Sets, Data Mining, and Granular-Soft Computing,2005. - Berlin : Springer. ; , s. 48-
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Konferensbidrag (refereegranskat)
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2. |
- Andersson, Robin, et al.
(författare)
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RoSy: A Rough Knowledge Base System
- 2005
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Ingår i: Rough Sets, Fuzzy Sets, Data Mining, and Granular Computing. - Berlin, Heidelberg : Springer Berlin Heidelberg. - 9783540286608 ; , s. 48-58
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Konferensbidrag (refereegranskat)abstract
- This paper presents a user-oriented view of RoSy, a Rough Knowledge Base System. The system tackles two problems not fully answered by previous research: the ability to define rough sets in terms of other rough sets and incorporation of domain or expert knowledge. We describe two main components of RoSy: knowledge base creation and query answering. The former allows the user to create a knowledge base of rough concepts and checks that the definitions do not cause what we will call a model failure. The latter gives the user a possibility to query rough concepts defined in the knowledge base. The features of RoSy are described using examples. The system is currently available on a web site for online interactions.
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3. |
- Assmann, Uwe, et al.
(författare)
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Combining safe rules and ontologies by interfacing of reasoners
- 2006
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Ingår i: Principles and Practice of Semantic Web Reasoning 4th International Workshop, PPSWR 2006, Budva, Montenegro, June 10-11, 2006, Revised Selected Papers. - Berlin, Heidelberg : Springer Berlin/Heidelberg. - 3540395865 - 9783540395867 ; , s. 33-47
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Bokkapitel (refereegranskat)abstract
- The paper presents a framework for hybrid combination of rule languages with constraint languages including but not restricted to Description-Logic-based ontology languages. It shows how reasoning in a combined language can be done by interfacing reasoners of the component languages. A prototype system based on the presented principle integrates Datalog with OWL by interfacing XSB Prolog [2] with a DIG-compliant [1] DL reasoner (e.g. Racer [17]).
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4. |
- Bry, Francois, et al.
(författare)
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On subtyping of tree-structured data : A polynomial approach
- 2004
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Ingår i: Principles and Practice of Semantic Web Reasoning. - Berlin, Heidelberg : Springer. - 9783540229612 - 9783540301226 ; , s. 1-18
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Konferensbidrag (refereegranskat)abstract
- This paper discusses subtyping of tree-structured data encountered on the Web, e.g. XML and HTML data. Our long range objective is to define a type system for Web and/or Semantic Web query languages amenable to static type checking. We propose a type formalism motivated by XML Schema and accommodating two concepts of subtyping: inclusion subtyping (corresponding to XML Schema notion of type restriction) and extension subtyping (motivated by XML Schema's type extension). We present algorithms for checking both kinds of subtyping. The algorithms are polynomial if certain conditions are imposed on the type definitions, the conditions seem natural and not too restrictive.
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5. |
- Bry, F, et al.
(författare)
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Principles and Practice of Semantic Web Reasoning : international workshop, PPSWR 2003, Mumbai, India, December 8, 2003 : proceedings
- 2003
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Bok (övrigt vetenskapligt/konstnärligt)abstract
- This book constitutes the refereed proceedings of the International Workshop on Principles and Practice of Semantic Web Reasoning, PPSWR 2003, held in Mumbai, India in December 2003 as satellite meeting of ICLP 2003. The 13 revised full papers presented were carefully reviewed and selected for inclusion in the proceedings. The papers are organized in topical sections on foundations of semantic Web reasoning, reasoning in practice, query- and rule-languages, and semantics and knowledge representation.
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6. |
- Drabent, Wlodzimierz, 1954-, et al.
(författare)
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Hybrid Reasoning with Rules and Constraints under Well-Founded Semantics
- 2007
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Ingår i: Web Reasoning and Rule Systems. - Berlin, Heidelberg : Springer Berlin/Heidelberg. - 9783540729815 - 354072981X ; , s. 348-357
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Konferensbidrag (refereegranskat)abstract
- The paper presents an architecture and implementation techniques for hybrid integration of normal clauses under well-founded semantics with ontologies specified in Description Logics. The described prototype uses XSB Prolog both for rule reasoning and for controlling communication with the ontology reasoner RacerPro. The query answering techniques for hybrid rules implemented in this prototype are sound wrt. the declarative semantics, extending the well-founded semantics of normal programs and are faithful wrt. FOL.
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7. |
- Drabent, Wlodzimierz, et al.
(författare)
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Hybrid Reasoning with Rules and Ontologies
- 2009
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Ingår i: Semantic Techniques for the Web, The REWERSE Perspective. - Berlin : pringer. - 9783642045806 ; , s. 1-49
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Bokkapitel (populärvet., debatt m.m.)abstract
- The purpose of this chapter is to report on work that has been done in the REWERSE project concerning hybrid reasoning with rules and ontologies. Two major streams of work have been pursued within REWERSE. They start from the predominant semantics of non-monotonic rules in logic programming. The one stream was an extension of non-monotonic logic programs under answer set semantics, with query interfaces to external knowledge sources. The other stream, in the spirit of the -log approach of enhanced deductive databases, was an extension of Datalog (with the well-founded semantics, which is predominant in the database area). The former stream led to so-called non-monotonic dl-programs and hex-programs, and the latter stream to hybrid well-founded semantics. Further variants and derivations of the formalisms (like a well-founded semantics for dl-programs, respecting probabilistic knowledge, priorities, etc.) have been conceived.
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8. |
- Drabent, Wlodzimierz, et al.
(författare)
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Hybrid Rules with Well-Founded Semantics
- 2010
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Ingår i: Knowledge and Information Systems. - Berlin : Springer. - 0219-1377 .- 0219-3116. ; 25:1, s. 137-168
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Tidskriftsartikel (refereegranskat)abstract
- A general framework is proposed for integration of rules and external first-order theories. It is based on the well-founded semantics of normal logic programs and inspired by ideas of Constraint Logic Programming (CLP) and constructive negation for logic programs. Hybrid rules are normal clauses extended with constraints in the bodies; constraints are certain formulae in the language of the external theory. A hybrid program consists of a set of hybrid rules and an external theory. Instances of the framework are obtained by specifying the class of external theories and the class of constraints. An example instance is integration of (non-disjunctive) Datalog with ontologies formalized in description logics. The paper defines a declarative semantics of hybrid programs and a goal-driven formal operational semantics. The latter can be seen as a generalization of SLS-resolution. It provides a basis for hybrid implementations combining Prolog with constraint solvers (such as ontology reasoners). Soundness of the operational semantics is proven. Sufficient conditions for decidability of the declarative semantics and for completeness of the operational semantics are given.
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9. |
- Drabent, Wlodek, et al.
(författare)
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Locating type errors in untyped CLP programs
- 2000
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Ingår i: Analysis and Visualization Tools for Constraint Programming. - Berlin : Encyclopedia of Global Archaeology/Springer Verlag. - 3540411372 - 9783540411376 - 9783540400165 ; , s. 121-150
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Bokkapitel (övrigt vetenskapligt/konstnärligt)abstract
- This chapter presents a static diagnosis tool that locates type errors in untyped CLP programs without executing them. The existing prototype is specialised for the programming language CHIP [4.10], but the idea applies to any CLP language. The tool works with approximated specifications which describe types of procedure calls and successes. The specifications are expressed as a certain kind of term grammars. The tool automatically locates at compile time all the errors (with respect to a given specification) in a program. The located erroneous program fragments are (prefixes of) clauses. The tool aids the user in constructing specifications incrementally; often a fragment of the specification is already sufficient to locate an error. The presentation is informal. The focus is on the motivation of this work and on the functionality of the tool. Some related formal aspects are discussed in [4.15, 4.29]. The prototype tool is available from http://www.ida.liu.se/~pawpi/Diagnoser/diagnoser.html.
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10. |
- Drabent, Wlodek, et al.
(författare)
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Parametric descriptive types for CLP
- 2001
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Ingår i: Programmation en logique avec contraintes. - Paris : Hermés Science Publications. - 2746202557 ; , s. 239-256
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Konferensbidrag (refereegranskat)
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