The OWL in the CASL: Designing Ontologies Across Logics

Due to the enormous growth of the volume of data and different structures, information systems are becoming increasingly complex. The Semantic Web aims to find, share and refine the information of current web more easily. The Semantic Web is a solution for representing the data in a machine understandable manner. Ontology is a powerful technology for representing the data in semantic web. Web Ontology Language (OWL) has been accepted as the knowledge representation standard by W3C. This paper proposes a unified and integrated framework, i.e., an Extended Hierarchical Censored Production Rules (EHCPRs) Framework for representing ontologies in Semantic Web, maintaining the knowledge treasures and doing reasoning over it. In addition, assuming that the framework is in place and is adopted, an algorithm is provided to convert the existing OWL ontologies into the EHCPRs Ontologies.The Protégé tool is used to create a trivial Vehicle Ontology and using the developed algorithm, it is converted into EHCPRs Ontology with no loss of information, i.e., preserving all the classes, their attributes and instances.

The current state of Semantic Web ontology languages is briefly described, and the ontology languages are characterised from the logical point of view. Generally, these languages are based on the first-order predicate logic enriched with ad hoc higher-order constructs wherever needed. We argue that in the Semantic Web we need a rich language with transparent semantics, in order to build up metadata on the conceptual level of the Semantic Web architecture. A powerful logical tool of Transparent Intensional Logic (TIL) is described, which provides a logico-semantic framework for a fine-grained knowledge representation and conceptual analysis. TIL is based on a rich ontology of entities organised in an infinite ramified hierarchy of types. The conceptual role of TIL in building ontologies is described, and we show that such a system can serve as a unifying logical framework. Concluding we argue that the conceptual and logical level of the Web architecture have an important role, and we...

Citeseer

In this paper, we show how the web ontology language OWL can be accommodated within the larger framework of the heterogeneous common algebraic specification language HETCASL. Through this change in perspective, OWL can benefit from various useful HETCASL features concerning structuring, modularity, and heterogeneity. This tackles a major problem area in ontology engineering: re-use of ontologies and re-combination of ontological modules. We discuss in particular:

Proc. of the 20th Int. Joint Conf …, 2007

Modularity is a key requirement for collaborative ontology engineering and for distributed ontology reuse on the Web. Modern ontology languages, such as OWL, are logic-based, and thus a useful notion of modularity needs to take the semantics of ontologies and their implications into account. We propose a logic-based notion of modularity that allows the modeler to specify the external signature of their ontology, whose symbols are assumed to be defined in some other ontology. We define two restrictions on the usage of the external signature, a syntactic and a slightly less restrictive, semantic one, each of which is decidable and guarantees a certain kind of "black-box" behavior, which enables the controlled merging of ontologies. Analysis of real-world ontologies suggests that these restrictions are not too onerous.

Journal of Artificial Intelligence Research, 2008

In this paper, we propose a set of tasks that are relevant for the modular reuse of ontologies. In order to formalize these tasks as reasoning problems, we introduce the notions of conservative extension, safety and module for a very general class of logic-based ontology languages. We investigate the general properties of and relationships between these notions and study the relationships between the relevant reasoning problems we have previously identified. To study the computability of these problems, we consider, in particular, Description Logics (DLs), which provide the formal underpinning of the W3C Web Ontology Language (OWL), and show that all the problems we consider are undecidable or algorithmically unsolvable for the description logic underlying OWL DL. In order to achieve a practical solution, we identify conditions sufficient for an ontology to reuse a set of symbols ``safely''---that is, without changing their meaning. We provide the notion of a safety class, w...

Journal of Web Engineering, 2005

Web Ontology Language (OWL) and Model-Driven Architectures (MDA) are two technologies being developed in parallel, but by different communities. They have common points and issues and can be brought closer together. Many authors have so far stressed this problem and have proposed several solutions. The result of these efforts is the recent OMG's initiative for defining an ontology development platform. However, the problem of transformation between ontology and MDA-based languages has been solved using rather partial and ad hoc solutions, most often by XSLT. In this paper we analyze OWL and MDA-compliant languages as separate technological spaces. In order to achieve a synergy between these technological spaces we define ontology languages in terms of MDA standards, recognize relations between OWL and MDA-based ontology languages, and propose mapping techniques. In order to illustrate the approach, we use an MDA-defined ontology architecture that includes ontology metamodel and ontology UML Profile. Based on this approach, we have implemented a transformation of the ontology UML Profile into OWL representation.

2004

The paper presents Ontology UML Profile (OUP); which, together with Ontology Definition Metamodel (ODM), enables the usage of Model Driven Architecture (MDA) standards in ontological engineering. Other similar metamodels and UML profiles are based on ontology representation languages, such as RDF(S), DAML+OIL, etc. However, none of these other solutions uses the recent W3C effort – The Web Ontology Language (OWL). In our approach, we firstly define the place of ODM and OUP in the context of the MDA four-layer architecture and identify the main OWL concepts. Then, to support ODM, we define OUP and describe its details. The proposed UML profile enables usage of the well-known UML notation in ontological engineering more extensively. We implemented an XSLT that transforms OUP ontologies into OWL in order to provide a suitable tool support.

proc. KR, 2006

Modularity in ontologies is key both for large scale ontology development and for distributed ontology reuse on the Web. However, the problems of formally characterizing a modular representation, on the one hand, and of automatically identifying modules within an OWL ontology, on the other, has not been satisfactorily addressed, although their relevance has been widely accepted by the Ontology Engineering and Semantic Web communities. In this paper, we provide a notion of modularity grounded on the semantics of OWL-DL. We present an algorithm for automatically identifying and extracting modules from OWL-DL ontologies, an implementation and some promising empirical results on real-world ontologies.

OntoUML and OWL are ontology languages appropriated to different knowledge representation levels. In order to have better knowledge representation and reasoning capabilities in OWL ontologies, an Ontology Engineering should be used – which corresponds to the transformation of a conceptual model ontology language, such as OntoUML, to a computational ontology language, such as OWL. This paper aims to bridge the expressivity gap between these languages through a Model Driven Architecture automated transformation from OntoUML to OWL with SWRL rules that contributes to (i) make easier the OWL creation from OntoUML, (ii) eliminate the human errors in this process, (iii) improve the resultant OWL ontology semantics.

Data & Knowledge Engineering, 2011

Many real-world ontologies contain thousands of terms and are developed by multiple participants. The use of monolithic ontologies can cause problems that affect various stages of the ontology life cycle. Thus, there is an urgent need for tools and methodologies that facilitate modular ontology design. The benefits of a modular approach include division of labor, scalability, partial reuse, and broadened participation. This article presents a methodology for modular ontology development. The main idea is to facilitate an interoperable hierarchical network of ontology modules. Modules are designed as a combination of more abstract modules in higher levels of the hierarchy. This methodology differs from previous methodologies in the way that it defines concrete development steps, to facilitate use by both naive and expert ontology developers. This methodology is also supported by ontology design patterns and a prototypical ontology development tool.