An ontology for software component matching

The Web is likely to be a central platform for software development in the future. We investigate how Semantic Web technologies, in particular ontologies, can be utilised to support software component development in a Web environment. We use description logics, which underlie Semantic Web ontology languages such as DAML+OIL, to develop an ontology for matching requested and provided components. A link between modal logic and description logics will prove invaluable for the provision of reasoning support for component and service behaviour

Building Rules on Top of Ontologies for the Semantic Web with Inductive Logic Programming

Building rules on top of ontologies is the ultimate goal of the logical layer of the Semantic Web. To this aim an ad-hoc mark-up language for this layer is currently under discussion. It is intended to follow the tradition of hybrid knowledge representation and reasoning systems such as $\mathcal{AL}$-log that integrates the description logic $\mathcal{ALC}$ and the function-free Horn clausal language \textsc{Datalog}. In this paper we consider the problem of automating the acquisition of these rules for the Semantic Web. We propose a general framework for rule induction that adopts the methodological apparatus of Inductive Logic Programming and relies on the expressive and deductive power of $\mathcal{AL}$-log. The framework is valid whatever the scope of induction (description vs. prediction) is. Yet, for illustrative purposes, we also discuss an instantiation of the framework which aims at description and turns out to be useful in Ontology Refinement. Keywords: Inductive Logic Programming, Hybrid Knowledge Representation and Reasoning Systems, Ontologies, Semantic Web. Note: To appear in Theory and Practice of Logic Programming (TPLP)Comment: 30 pages, 6 figure

Some Classical Problems of Inheritance Networks in the Light of Defeasible Ontology Reasoning

Reasoning with possibly inconsistent ontologies is an important reasearch topic for the implementation of the Semantic Web as they pose a problem for performing instance checking. We contend that Defeasible Logic Programming (DeLP) is a reliable tool for doing ontology reasoning when Description Logic ontologies can be interpreted as DeLP programs. In this work we present some classical problems of the eld of inheritance networks and show how they are modeled as inconsistent ontologies and thus how the problem of instance checking is solved; we also show how issues in reasoning with argumentation frameworks based on Dung's grounded semantics are also solved when applied to ontology reasoning, and we revise the main algorithm for instance checking when using DeLP with inconsistent ontologies.Eje: XV Workshop de Agentes y Sistemas InteligentesRed de Universidades con Carreras de Informática (RedUNCI

Some Classical Problems of Inheritance Networks in the Light of Defeasible Ontology Reasoning

Reasoning with possibly inconsistent ontologies is an important reasearch topic for the implementation of the Semantic Web as they pose a problem for performing instance checking. We contend that Defeasible Logic Programming (DeLP) is a reliable tool for doing ontology reasoning when Description Logic ontologies can be interpreted as DeLP programs. In this work we present some classical problems of the eld of inheritance networks and show how they are modeled as inconsistent ontologies and thus how the problem of instance checking is solved; we also show how issues in reasoning with argumentation frameworks based on Dung's grounded semantics are also solved when applied to ontology reasoning, and we revise the main algorithm for instance checking when using DeLP with inconsistent ontologies.Eje: XV Workshop de Agentes y Sistemas InteligentesRed de Universidades con Carreras de Informática (RedUNCI

Reasoning with inconsistent ontologies in possibilistic defeasible logic programming

We present a preliminary framework for reasoning with possibly inconsistent Description Logic ontologies in Possibilistic Defeasible Logic Programming. A case study is presented where we show how the proposed approach works. The proposal presented is apt for being used in the context of Semantic Web ontologies as it can be applied to the Web Ontology Language OWLPresentado en el XII Workshop Agentes y Sistemas Inteligentes (WASI)Red de Universidades con Carreras en Informática (RedUNCI

Enhancing Simulation Composability and Interoperability Using Conceptual/Semantic/Ontological Models

(First paragraph) Two emerging trends in Modeling and Simulation (M&S) are beginning to dovetail in a potentially highly productive manner, namely conceptual modeling and semantic modeling. Conceptual modeling has existed for several decades, but its importance has risen to the forefront in the last decade (Taylor and Robinson, 2006; Robinson, 2007). Also, during the last decade, progress on the Semantic Web has begun to influence M&S, with the development of general modeling ontologies (Miller et al, 2004), as well as ontologies for modeling particular domains (Durak, 2006). An ontology, which is a formal specification of a conceptualization (Gruber et al, 1993), can be used to rigorously define a domain of discourse in terms of classes/concepts, properties/relationships and instances/individuals. For the Semantic Web, ontologies are typically specified using the Web Ontology Language (OWL). Although, conceptual modeling is broader than just semantics (it includes additional issues such as pragmatics (Tolk et al, 2008)), progress in the Semantic Web and ontologies is certainly beneficial to conceptual modeling. Benefits are accrued in many ways including the large knowledge bases being placed on the Web in numerous fields in which simulation studies are conducted and the powerful reasoning algorithms based on description logic being developed that allow the consistency of large specifications to be checked

Inductive Logic Programming in Databases: from Datalog to DL+log

In this paper we address an issue that has been brought to the attention of the database community with the advent of the Semantic Web, i.e. the issue of how ontologies (and semantics conveyed by them) can help solving typical database problems, through a better understanding of KR aspects related to databases. In particular, we investigate this issue from the ILP perspective by considering two database problems, (i) the definition of views and (ii) the definition of constraints, for a database whose schema is represented also by means of an ontology. Both can be reformulated as ILP problems and can benefit from the expressive and deductive power of the KR framework DL+log. We illustrate the application scenarios by means of examples. Keywords: Inductive Logic Programming, Relational Databases, Ontologies, Description Logics, Hybrid Knowledge Representation and Reasoning Systems. Note: To appear in Theory and Practice of Logic Programming (TPLP).Comment: 30 pages, 3 figures, 2 tables

The limits and possibilities of combining Description Logics and Datalog

Description Logics are currently the most used formalisms for building ontologies, and have been proposed as standard languages for the specification of ontologies in the Semantic Web. The problem of adding rules to Description Logics is currently a hot research topic, due to the interest of Semantic Web applications towards the integration of rule-based systems with ontologies. Most of the approaches in this field concern the study of description logic knowledge bases augmented with rules expressed in Datalog and its nonmonotonic extensions. In this talk we present a set of computational results which identify, from the viewpoint of the expressive abilities of the two formalisms, minimal combinations of Description Logics and (nonmonotonic) Datalog in which reasoning is undecidable. Then, based on the above results, we briefly survey some recent proposals for overcoming such expressive limitations. © 2006 IEEE

Some Classical Problems of Inheritance Networks in the Light of Defeasible Ontology Reasoning

Reasoning with possibly inconsistent ontologies is an important reasearch topic for the implementation of the Semantic Web as they pose a problem for performing instance checking. We contend that Defeasible Logic Programming (DeLP) is a reliable tool for doing ontology reasoning when Description Logic ontologies can be interpreted as DeLP programs. In this work we present some classical problems of the eld of inheritance networks and show how they are modeled as inconsistent ontologies and thus how the problem of instance checking is solved; we also show how issues in reasoning with argumentation frameworks based on Dung's grounded semantics are also solved when applied to ontology reasoning, and we revise the main algorithm for instance checking when using DeLP with inconsistent ontologies.Eje: XV Workshop de Agentes y Sistemas InteligentesRed de Universidades con Carreras de Informática (RedUNCI

Hypertableau Reasoning for Description Logics

We present a novel reasoning calculus for the description logic SHOIQ^+---a knowledge representation formalism with applications in areas such as the Semantic Web. Unnecessary nondeterminism and the construction of large models are two primary sources of inefficiency in the tableau-based reasoning calculi used in state-of-the-art reasoners. In order to reduce nondeterminism, we base our calculus on hypertableau and hyperresolution calculi, which we extend with a blocking condition to ensure termination. In order to reduce the size of the constructed models, we introduce anywhere pairwise blocking. We also present an improved nominal introduction rule that ensures termination in the presence of nominals, inverse roles, and number restrictions---a combination of DL constructs that has proven notoriously difficult to handle. Our implementation shows significant performance improvements over state-of-the-art reasoners on several well-known ontologies