Research On Organizing And Processing Of Context-Centered Roles Concept

The concept of "ontology" originated from philosophy and has been given anew definition nowadays in artificial intelligence community with thedevelopment of artificial intelligence. With good taxonomic hierarchies and thelevel of support for logical reasoning, it has a wide range of applications inknowledge retrieval, concept modeling and natural language understanding. In thesemantic Web, ontology is also very important, because it is the basis for solvingsemantic level Web based on information sharing and exchange. Theoreticalresearch on ontology includes the Conceptualization Concept Classification andOntology Algebra. Currently, Ontological Engineering attracts a lot of attention inmany research areas and has been investigated from various view points:fundamental theory, development, application, and so on.Gruber presented the five guiding principles of ontology modeling: Clarity,Coherence, Extendibility, Minimal encoding eras and Minimal ontologicalcommitment. Mariano summed up the current five typical means for buildingontology: the Uschold and King methods, Gruninger and Fox methods, Bernerasmethods, methontology methods and methods based on Sensus.Building an effective ontology needs a clear understanding of concepts andtheir relationships in this field. Therefore, constructing ontology should primarilyfocus on the areas of conceptualization. Nicola Guarino has described Formalontology as a field "intended as a theory of a priori distinctions" along two lines.On the one hand, the entities of reality have to be classified (for instance, asphysical objects, processes, regions, etc.). On the other hand, meta-level categoriesused in such world models (e.g., concepts, properties, roles, etc.) are to bedistinguished. In the last ten years, the role concepts are often discussed in variousfields of computer science literature, such as the concept modeling and knowledgerepresentation and so on. However, a comprehensive definition of the concept hasnot been determined. Related literature dissertate its generic methods, includingclassification system, and integrated well constructed ones into the concept ofknowledge-based language GOL.GOL involves two concepts associated with role: player and context. "IS_A"relationship undoubtedly is the most important relationship in the real world, butin the concept modeling, different "IS_A" understanding produced semanticambiguity. Guarino detailed "IS_A" overload issue and explained them as roleconfusion. John Sowa presented Firstness and Secondness concept. RiichiroMizoguchi divided it into a basic concept, a role concept and a role holder,andsummarized the fundamental relationship as "IS_A", "part of", "attribeOf"relations.Ontology development is part of ontology engineers, and needs suitabledevelopment environment, which is used to help people quickly and effectively toestablish ontology, such as OilEd, Protégé, WebOnto and Hozo. Based on the basicconcept of ontology, Hozo focused on "role concept" and "relationship" and howto deal with these concepts in Hozo environment.Object-oriented thinking and methods used in the modeling of ontology willlead to revolutionary changes in the ontology development process. Ontologyclassification, extraction and the determination of the relationship are similar withthe UML modeling analysis, design.In taxonomic hierarchies, a concept may have different context, so leads tosemantic confusion. Guarino concluded five categories of semantic confusion.Some semantic confusion solved by the understanding of a person or definitionextension, and some semantic confusion, such as semantic conflict, can possiblyavoid through personality concept models.Roles are introduced to knowledge expression and data/conceptual modelingfor the realization. Roles are used in many models such as logic description, script,Sowa's ontology and E-R model, object-oriented modeling, agent-orientedmodeling, object-process methods in the field of concept modeling.Based on status, role and approach of roles in various models, this paperanalyses dependence relation between the roles and context and presents theorganization method for multi-context roles.Context dependence is one of the important characteristics of roles andexplains how and why an entity changes its roles to play. Context can be dividedinto three categories: RELATION, PROCESS, SUBSTANCE. According torelation between the roles and their context, Roles can be divided into threecategories: RELATION ROLE, PROCESS ROLE and SOCIAL ROLE. Thefollowing points can be summarized to hold for all roles:Each role is an individual.Each role has exactly one player.There is at least one context for each role.If there are multiple contexts,—all of these belong to exactly one of the categories realtors, process, orsubstance thus far, but there may be more context-providing categories.—these contexts are in some way related to part-Of.VINo role is a context of another role.Role concepts are represented in the form of part or participant. However,when concepts act as various contexts, they contain more semantics. They areregulated in their context dependency. Therefore, they can be organized accordingto categories of context and formalities of the dependencies. We consider that thereare, at least, the following six kinds of a role-concept: Task context role, Domaincontext role, Function context role, Action context role, Capacity context role,State context roleAccording to mutual relations of roles and context, based on multi-contextdependence of role concept, we reached conclusions of steps on building ontologyas follows:1. Construct a basic concept structure.2. Role is defined at the top of the hierarchy of role concepts as a class whichhas three slots. The first is related by a participate-in relation and describes in whatcontext the role concept is recognized. The second is also related by aparticipate-in relation and show a basic concept which can carry the role concept.The third is related by a part-of relation and associated with role aggregation3. Organizing role concepts according to classification of their contexts.Because role concepts are generally regulated in their context-dependencies, theycan be organized according to categories of their contexts and formalities of thedependences. In the basic concepts hierarchies, the relationship as context of roles,the roles will be divided into four categories: relations role, process roles, andsocial roles and context independent roles.4. There are three ways to organize role concept of which is dependent onindividual context:(1) Role concepts are organized according to the aspects of entity playing theroles and manners of its participation into contexts.(2) The second is to organize role concepts based on an "IS_A" relationbetween basic concepts as contexts.(3) For organizing role concepts appropriately, it is indispensable to definerole concepts which cannot be described in a hierarchy of basic concepts.Such role concepts are defined for constraint of contexts as intermediateconcepts among role concepts described in a hierarchy of basic concepts.They are used mainly for constraint of contexts and not instantiateddirectly.5. Many of the individuals play a role-concept which depends on severalcontexts rather than a single context. We choose the most essential context amongthem. The other context dependencies are described as participating conceptsthrough part-of relations.6. For those context can not be identified, they are usually defined as thesub-concept of role concept relied on different contexts, and then linked with therelationship "equivalent".In accordance with the conclusions of the theory, this paper actuallyconstituted an ontology model --teaching ontology. In the process of modeling, wecombine theoretical conclusions, the development environment Hozo and otherrelevant theories and techniques to make theoretical models have advanced,technical feasibility, and the practice of usability.In the last, we noted the imperfection of the work and pointed out thedirection for continued efforts.