Ontologies constitute a pertinent mean to define and to manage competencies and knowledge in companies. The powerful inference mechanisms coming with ontologies allow improving the effectiveness of complex competence and knowledge management processes. This paper represents a short synthesis on ontology definition, building and application. Then, thinking about interest of competence ontology and its building is exposed.
Enterprise competence and knowledge constitutes vast amounts of information resources to represent, to store and to process. They are treated to answer to many enterprise complex needs. For that, it seems necessary to build a formal ontology of enterprise competence and knowledge. This ontology would concern enterprise knowledge, competence and domain. It can be composed of three integrated ontologies: domain ontology, competence ontology and knowledge ontology. Links between them should be defined in order to pass from one to another (Fig. 1). Representation of enterprise domain constitutes a part of enterprise knowledge, but we consider it separately in order to distinguish it of other kinds of knowledge (e.g. knowledge of tasks, knowledge of facts).
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O nto lo g y D o m ain O nto lo gy
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K 3 Reasoning on this ontology will concern the verification of the ontology consistence, the semi-automated adding of new competencies, domain aspects or knowledge, the supporting of competency and knowledge management, and so on.
In this paper, we only deal with competence ontology. First, a brief synthesis about ontology definition and building is presented. Then, a vision concerning specially competence ontology building and its components is presented. 2
Ontology Definition and Building Many definitions have been proposed for the ontology in computer sciences. Several definition invariant can be find out:
An ontology concerns a domain [
Domain
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C2 Ontology 3 C1 et C2 =>C3 C3 => non C4 C1 => C4 etc.
C1, C2, C3, C4 – Concepts
C4 Axioms Predicates
Ontology 1 C1 Definition C2 Definition C3 Definition C4 Definition
Dictionary
Vocabularies Entities Objects
Relations Ontology 2 Part-of
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Three kinds of building methods concerning ontologies can be distinguished: 1)
Manual methods where experts of a specific domain built a new ontology or extend an
existent ontology (for instance, the high level of Cyc [
Ontologies allow mainly to develop applications for extracting knowledge, for carrying out intelligent search in the web, for translating documents; for sharing the comprehension of information between application users and developers; for understanding and re-using the knowledge of a specific domain, and so on. 3 Competence Ontology Building A competence ontology supports both the competency intra-operability and interoperability over applications and users. Concerning competence intra-operability, it allows: 1) The shared comprehension of competencies and their using. 2) The unification of competence identification and evaluation. So, the decentralization of these processes is possible, once the competence semantic is ensured by the competence ontology. 3) The simplification of processing of curriculum vitae by expliciting it in the enterprise competence ontology. 4) The integration of competence reference grids of different workshops or departments. This is important when the enterprise reorganizes its structure and defines new workstations, and so on. Concerning competency interoperability, competence ontology allows sharing and exchanging competencies of an enterprise network (including supplier, subcontractor, and partner) by integrating their competence reference grids. Indeed, competence ontology allows translating the competence reference grid of each enterprise on a unified ontology, so unified semantic is used on enterprise network competence management.
It is clear that competence ontology concerns the competencies related to a specific domain. This ontology is composed of competencies related between them. But, two points, at least, remain to be clarified:
The kind of relationships between competencies. Relationships - as Is-a or Part-of
explaining aggregation of competencies, or the relationship explaining that an
individual should have a given competency to acquire another one – can be used. Other
relationship kinds are not evident to use!
What concepts would be on a competence ontology? Should a competence
ontology includes only competencies or should it include another’s concepts concerning,
for example the studied domain, its knowledge?
We are interested to tow methods for competence ontology building: domain based
method and competence similarity based method. Both are based on the model CRAI
(Competency Resource Aspect individual) [
The first method consists to define a competence ontology by building first an ontology of the domain (mainly by specialization of Aspect and further instantiation). Then, the relationship To-Concern (Cf. Fig. 3) is defined between competencies and domain aspects instances. The obtained result is it a competency ontology? We are beginning the competency ontology building of the computer domain of the company Cap Gemini, Nantes - France, using this method (Fig 4).
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To-K-now Be-Associated 0,n Competency To-Behave 1,n
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0,n Aspect 1,n Decomposed-In 1,n The second method (competence similarity based) consists to build a competency ontology by extracting competency similarity rules, according to their likelihood. A similarity rule is as follow: c1, c2, ..., ck cn where ci is any competency. The underling meaning of this rule is that if the competencies c1, c2, ..., ck are acquired by any individual then cn is acquired by the same individual. The likelihood of a similarity rule is calculated with an index, based on the nature of competencies (their CResources and Aspects concerned by them). In the sense, that the definition of similarity link between tow competencies c1 and c2, for example, that concern respectively {a1, a3} and {a2, a3} are based, on one hand, on the similarity of {a1, a3} and {a2, a3} and, on the other hand, on their common resources {rt1, r31, r32}. c1 and c2 have respectively {r11, r12, r13, rt1, r31, r32} and {r21, rt1, rt2, r31, r32}, rti is a transversal C-resource associated to one or more competencies.
PL/SQL SQL Net
This approach defines direct links (of similarity kind) between competencies. However, do these competence links constitute a competence ontology? In the both cases, obtained results concern a domain. In the first case, relationships between domain concepts are defined, then relationships between competencies and domain concepts are defined and by deduction competencies relationships can be defined. In the second case, direct relationships between competencies are defined. To integrate a new competence (or a competence set) in the obtained result, in the first case, it is clear that its concerned aspect should be positioned in the domain ontology. In the second case, it should define its resources and concerned aspects, compared to existing resources and aspects. In other word, data about it should be positioned in the domain ontology. In conclusion, it seems that the tow methods can be integrated to give more semantic to competence relationships.
In this paper, we have discussed some ways to build competence ontology. Two competence “pseudo-ontologies” based on domain and competence similarity definition have been presented. However, components and relationships that should constitute a competence ontology remain not clear. In other words, when can and can’t a competency schema be considered as a competence ontology? More generally, when have and haven’t we dealt with ontology?