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Managing Uncertainty and Vagueness in Description Logics for the Semantic Web
, 2007
"... Ontologies play a crucial role in the development of the Semantic Web as a means for defining shared terms in web resources. They are formulated in web ontology languages, which are based on expressive description logics. Significant research efforts in the semantic web community are recently direct ..."
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Cited by 135 (14 self)
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Ontologies play a crucial role in the development of the Semantic Web as a means for defining shared terms in web resources. They are formulated in web ontology languages, which are based on expressive description logics. Significant research efforts in the semantic web community are recently directed towards representing and reasoning with uncertainty and vagueness in ontologies for the Semantic Web. In this paper, we give an overview of approaches in this context to managing probabilistic uncertainty, possibilistic uncertainty, and vagueness in expressive description logics for the Semantic Web.
Probabilistic description logic programs
, 2006
"... Towards sophisticated representation and reasoning techniques that allow for probabilistic uncertainty in the Rules, Logic, and Proof layers of the Semantic Web, we present probabilistic description logic programs (or pdl-programs), which are a combination of description logic programs (or dl-prog ..."
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Cited by 43 (15 self)
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Towards sophisticated representation and reasoning techniques that allow for probabilistic uncertainty in the Rules, Logic, and Proof layers of the Semantic Web, we present probabilistic description logic programs (or pdl-programs), which are a combination of description logic programs (or dl-programs) under the answer set semantics and the well-founded semantics with Poole’s independent choice logic. We show that query processing in such pdl-programs can be reduced to computing all answer sets of dl-programs and solving linear optimization problems, and to computing the well-founded model of dl-programs, respectively. Moreover, we show that the answer set semantics of pdl-programs is a refinement of the well-founded semantics of pdl-programs. Furthermore, we also present an algorithm for query processing in the special case of stratified pdl-programs, which is based on a reduction to computing the canonical model of stratified dl-programs.
Semantics for the semantic web: the implicit, the formal and the powerful
- International Journal on Semantic Web and Information Systems
, 2005
"... Enabling applications that exploit heterogeneous data in the Semantic Web will require us to harness a broad variety of semantics. Considering the role of semantics in a number of research areas in computer science, we organize semantics in three forms: implicit, formal and powerful, and explore the ..."
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Cited by 42 (2 self)
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Enabling applications that exploit heterogeneous data in the Semantic Web will require us to harness a broad variety of semantics. Considering the role of semantics in a number of research areas in computer science, we organize semantics in three forms: implicit, formal and powerful, and explore their roles in enabling some of the key capabilities related to the Semantic Web. The central message of this paper is that building the Semantic Web purely on description logics will artificially limit it potential, and that we will need to both exploit well known techniques that support implicit semantics, and
General concept inclusions in fuzzy description logics
- In Proceedings of the 17th International Conference on Artificial Intelligence (ECAI 06
, 2006
"... Abstract. Fuzzy Description Logics (fuzzy DLs) have been proposed as a language to describe structured knowledge with vague concepts. A major theoretical and computational limitation so far is the inability to deal with General Concept Inclusions (GCIs), which is an important feature of classical DL ..."
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Cited by 33 (13 self)
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Abstract. Fuzzy Description Logics (fuzzy DLs) have been proposed as a language to describe structured knowledge with vague concepts. A major theoretical and computational limitation so far is the inability to deal with General Concept Inclusions (GCIs), which is an important feature of classical DLs. In this paper, we address this issue and develop a calculus for fuzzy DLs with GCIs. 1
Fuzzy Description Logic Programs under the Answer Set Semantics for the Semantic Web
- WEB, SECOND INTERNATIONAL CONFERENCE, RULEML
, 2006
"... Vagueness and imprecision abound in multimedia information processing and retrieval. In this paper, towards dealing with vagueness and imprecision in the reasoning layers of the Semantic Web, we present an approach to fuzzy description logic programs under the answer set semantics. We generalize nor ..."
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Cited by 28 (7 self)
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Vagueness and imprecision abound in multimedia information processing and retrieval. In this paper, towards dealing with vagueness and imprecision in the reasoning layers of the Semantic Web, we present an approach to fuzzy description logic programs under the answer set semantics. We generalize normal description logic programs (dl-programs) under the answer set semantics by fuzzy vagueness and imprecision. We define a canonical semantics of positive and stratified fuzzy dl-programs in terms of a unique least model and iterative least models, respectively. We then define the answer set semantics of general fuzzy dlprograms, and show in particular that all answer sets of a fuzzy dl-program are minimal models, and that the answer set semantics of positive and stratified fuzzy dl-programs coincides with their canonical least model and iterative least model semantics, respectively. Furthermore, we also provide a characterization of the canonical semantics of positive and stratified fuzzy dl-programs in terms of a fixpoint and an iterative fixpoint semantics, respectively.
AN OVERVIEW OF UNCERTAINTY AND VAGUENESS IN DESCRIPTION LOGICS FOR THE SEMANTIC WEB
, 2006
"... Ontologies play a crucial role in the development of the Semantic Web as a means for defining shared terms in Web resources. They are formulated in web ontology languages, which are based on expressive description logics. Significant research efforts are recently directed towards representing and ..."
Abstract
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Cited by 22 (7 self)
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Ontologies play a crucial role in the development of the Semantic Web as a means for defining shared terms in Web resources. They are formulated in web ontology languages, which are based on expressive description logics. Significant research efforts are recently directed towards representing and reasoning with uncertainty and vagueness in ontologies for the Semantic Web. In this paper, we give an overview of probabilistic uncertainty, possibilistic uncertainty, and vagueness in expressive description logics for the Semantic Web.
Tightly integrated fuzzy description logic programs under the answer set semantics for the semantic web
- In RR
, 2007
"... Abstract. We present a novel approach to fuzzy dl-programs under the answer set semantics, which is a tight integration of fuzzy disjunctive programs under the answer set semantics with fuzzy description logics. From a different perspective, it is a generalization of tightly integrated disjunctive d ..."
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Cited by 19 (2 self)
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Abstract. We present a novel approach to fuzzy dl-programs under the answer set semantics, which is a tight integration of fuzzy disjunctive programs under the answer set semantics with fuzzy description logics. From a different perspective, it is a generalization of tightly integrated disjunctive dl-programs by fuzzy vagueness in both the description logic and the logic program component. We show that the new formalism faithfully extends both fuzzy disjunctive programs and fuzzy description logics, and that under suitable assumptions, reasoning in the new formalism is decidable. Furthermore, we present a polynomial reduction of certain fuzzy dl-programs to tightly integrated disjunctive dl-programs. We also provide a special case of fuzzy dl-programs for which deciding consistency and query processing have both a polynomial data complexity. 1
Fuzzy Description Logic Programs
, 2007
"... Description Logic Programs (DLPs), which combine the expressive power of classical description logics and logic programs, are emerging as an important ontology description language paradigm. In this study, we present fuzzy DLPs, which extend DLPs by allowing the representation of vague/imprecise inf ..."
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Cited by 19 (10 self)
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Description Logic Programs (DLPs), which combine the expressive power of classical description logics and logic programs, are emerging as an important ontology description language paradigm. In this study, we present fuzzy DLPs, which extend DLPs by allowing the representation of vague/imprecise information.
f-SWRL: A fuzzy extension of SWRL
- Journal on Data Semantics, special issue on Emergent Semantics
"... Abstract. Although the combination of OWL and Horn rules results in the creation of a highly expressive language, i.e. SWRL, there are still many occasions where this language fails to accurately represent knowledge of our world. In particular, SWRL fails at representing vague and imprecise knowledg ..."
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Cited by 18 (6 self)
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Abstract. Although the combination of OWL and Horn rules results in the creation of a highly expressive language, i.e. SWRL, there are still many occasions where this language fails to accurately represent knowledge of our world. In particular, SWRL fails at representing vague and imprecise knowledge and information. Such type of information is apparent in many applications like multimedia processing and retrieval, information fusion, etc. In this paper, we propose f-SWRL, a fuzzy extension to SWRL to include fuzzy assertions (such as ‘Mary is tall in the degree of 0.9’) and fuzzy rules (such as ‘being healthy is more important than being rich to determine if one is happy’). 1
On the expressiveness of the languages for the Semantic Web — Making a case for “A little more
- Fuzzy Logic and the Semantic Web, Capturing Intelligence
, 2006
"... "So far as the laws of mathematics refer to reality, they are not certain. And so far as they are certain, they do not refer to reality." ..."
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Cited by 7 (1 self)
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"So far as the laws of mathematics refer to reality, they are not certain. And so far as they are certain, they do not refer to reality."
