Special aspects of the ontological approach application in intelligent system development for certain types of problems in chemistry

The article describes several aspects of the ontological approach application to the intelligent system development. This approach is grounded on the application domain modeling by means of applied logic theories. The basic thesaurus for the development of professional activity models is created (based on the ontological approach). All the definitions from this dictionary are presented. The examination of the “Atomic weight” term and other chemistry term evolution brings to the sharp focus the fact that in the knowledge-intensive application domains not only the knowledge but also the ontology changes over time. Consequently, intelligent system developer should consider the opportunity of knowledge and metaknowledge alteration to prolong the intelligent system lifecycle and intelligent system update. For this purpose, intelligent system development should start after the application domain specification modelling. The created algorithm for the development of the application domain specification, which includes three steps: ontological analysis of the application domain, the major purpose of which consists in the search of the adequate conceptualization, includes the following subtasks: informal problem statement, concept analysis, scope analysis, situation analysis - synthesis of the application domain model and proving the hypothesis of the model adequacy. The steps of the algorithm are supported by the description of the intellectual activity task solution. This problem is the classification problem. The novelty of the article is the solution developed for the classification of the chemical elements in Mendeleev’s Periodic table based on the values of the isotope abundance and atomic weight. Major steps of application domain ontology model development are illustrated with the help of the solution to the stated problem. The model that this article provides includes the knowledge ontology and the situation ontology. The key steps of the application domain specification development: ontological analysis, ontology model synthesis, and adequacy criteria - are discussed the most thoroughly.