Metamodeling Of Two-dimensional Description Logics And Its Applications

Ontology is a term borrowed from philosophy, where ‘Ontology’ is a systematicaccount of existence. After imported into Information Technology domain, ontologyacts as “a formal specification of a shared conceptualization” and is applied toeverywhere of Information Technology domain, especially it acts a veryimportant role in the next-generation World Wide Web–Semantic Web. OntologyEngineering is formally defined as “the set of activities that concern the ontologydevelopment process, the ontology life cycle, and the methodologies, tools, andlanguages for building ontologies”. Application of large-scale ontologies brings a lotof requirements to Ontology Engineering, and among these requirements, ontologyalignment, ontology reuse and ontology evolution become the most difficult andimportant parts. At the same time, with the development of semantic web, contextontology becomes an important research direction of ontology engineering, and itbecomes a new solution for application of large-scale ontologies.Description Logics are the formal foundations of current mainstream ontologylanguages. With the development of ontology, description logics are beinginvestigated deeply. A new formal description tool named Two-DimensionalDescription Logics is provided by researchers in description logics domain. As aformal foundation for modeling and analyzing context ontologies, it provides a newway to support application of context ontologies. However, two-dimensionaldescription logics are still on their early stages, many theoretical and practicalproblems to be solved. This paper focuses on metamodeling of two-dimensionaldescription logics, and provides some achievements related to research andapplication two-dimensional description logics. It provides foundation for furtherresearch and application on two-dimensional description logics, and provides supports for application of context ontologies on ontology engineering and semantic web. Tobe more specific, works are done on the following aspects:1. To Provide a metamodeling method for two-dimensional description logicsModel-Driven Architecture (MDA) is an important direction of Software Engineering.It is a software development framework where the core is a set of automatictransformation of models. The kernel of MDA is a meta-meta model that can be usedto modeling other metamodels; its name is Meta Object Facility (MOF). Researchersfound that the two standalone domains, MDA and semantic web, have similarities,and research achievements of the two domains can be referenced each other, so theysuggest to bridge these two domains. The new domain is named Model-DrivenSemantic Web. Object Management Group (OMG) adopts Ontology DefinitionMetamodel (ODM) as a standard for this goal, and ODM becomes the most importantachievement in the domain.Following the idea of MDA and ODM, a metamodeling method fortwo-dimensional description logics is provided in the paper. Steps of the method are:to abstract two-dimensional description logics to specifications in ExtendedBackus-Naur Form (EBNF), to translate them into elements of metamodelscompatible to MOF automatically, and then to add semantic restrictions into the set ofmetamodel elements to finish metamodels.2. To provide some metamodels for two-dimensional description logicsTwo-dimensional description logic is a family of description logics with differentexpressions. By applying the metamodeling method for two-dimensional descriptionlogics, different metamodels for the family of two-dimensional description logics areprovided in the paper, comparisons of different metamodels are provided, andgraphical descriptions of different metamodels are also provided. There metamodelsare the cores of the paper, they are formal foundations for further research andapplication on two-dimensional description logics.3. To provide an extended Web Ontology Language for context ontologiesW3C provides many language standards for semantic web, such as RDF/RDFS andOWL. By referencing these language standards and mappings between thesestandards and ODM, a context ontology language named Two-Dimensional WebOntology Language (2DOWL) based on two-dimensional description logicmetamodels is provided in the paper, and W3C compatible syntax and semantics for this language are also provided.2DOWL is an extension of and compatible withcurrent languages, such RDF/RDFS and OWL, it can reuse current tools andtechniques for these current languages, it can help application of two-dimensionaldescription logics very directly.4. To provide a metamodel-based measurement method for two-dimensionaldescription logicsOntology measurement is an important evaluation and quantification method forontologies. It is very important on application of large-scale ontologies, especially onontology reuse. By referencing software measurement from Software Engineering, agraphical model for two-dimensional description logic ontologies is provided basedon two-dimensional description logic metamodels, and a two-dimensional descriptionlogics measurement method based on this graphical model is also provide in the paper.Some basic but important measurement criteria are also provided. The measurementmethod is extensible, measurement criteria can be added based on requirements, andthe method can help to finish many complex measurements.5. To design and implement a modeling tool for two-dimensional description logicsThere are a lot of tools and techniques that can help modeling and translating modelsin MDA domain. Based on Eclipse platform, by using tools and techniques of Eclipseplatform, such as EMF, GEF and GMF, a suit of modeling tools for two-dimensionaldescription logics is designed and implemented. It can help application oftwo-dimensional description logics.6. To discuss and analyze application domains of two-dimensional description logicsThere are two natural application scenarios for the two-dimensional description logics.First, they can be used as native representation languages dedicated to modeling andreasoning about knowledge of inherently contextualized nature. Alternatively, theframework can be used to support an external ’integration’ layer over standarddescription logic ontologies. In this paper, analysis on application of two-dimensionaldescription logics on contextual knowledge base and contextual reasoning areprovided, and analysis on application of two-dimensional description logics onontology engineering, especially on ontology alignment, ontology reuse and ontologyevolution are also provided.The research mentioned in this paper solves some problems of two-dimensionaldescription logics on modeling, measurement and application. The achievements will provide valuable reference for two-dimensional description logics on research andapplication.