Jerinić, Lj. Devedžić, V. and Radović D., The Object Model of the Control Knowledge for Intelligent Tutoring. In Đ Nadrljanski and D. Lipovac (Eds.) Proceedings of 7th International Conference "Informatics in Education and New Information Technologies" (7th - 8th November, Novi Sad, Yugoslavia). Printing- house of Executive Council of Vojvodina, Novi Sad, 1997, pp. 37-44. THE OBJECT MODEL OF THE CONTROL KNOWLEDGE FOR INTELLIGENT TUTORING OBJEKTNI MODEL KONTROLE ZNANJA U INTELIGENTNIM TUTORIMA Ljubomir Jerinic 1 , Vladan Devedzic 2 and Danijela Radovic 3 1 Institute of Mathematics, University of Novi Sad 2 FON - School of Business Administration, University of Belgrade 3 University of Kragujevac, Technical Faculty Cacak Abstract. The difficulty of designing and developing more useable and cost-effective intelligent tutoring systems (ITSs) has caused the realization of some new approaches in that field, the realization of intelligent tutoring shells. Our starting point and perspective on developing ITSs shell is motivated by issues of pragmatics and usability. The advancement of AI methods and techniques makes understanding of ITSs more difficult, so that the teachers are less and less prepared to accept these systems. As a result, the gap between the researchers in the field of ITSs and the educational community is constantly widening. Also, the present ITSs need quite big development environments, huge computing resources and, in consequence, are expensive and hardly portable to personal computers. Considering commercially available and widely used authoring systems for traditional computer-based teaching, we try to give the next step, the next paradigm shift that is needed to enable some of the advantages of ITSs in that tools. The paper describes an object- oriented model of control knowledge of the ITS shell in which the end-user (teacher) could make their own ITS lessons, alone. 1. INTRODUCTION Traditional Intelligent Tutoring Systems (ITSs) [1, 2, 3] are concentrated on the fields (domains) they are supposed to present, hence their control mechanisms are often domain-dependent. More recent ITSs pay more attention to generic problems and concepts of the tutoring process, trying to separate architectural, methodological, and control issues from the domain knowledge as much as possible. This was also one of the main ideas behind the ITS shell (environment) called EduSof [4, 5, 6], designed to allow fast prototyping of ITSs in different domains. However, the original design of EduSof's mechanisms for representing domain and control knowledge has proved to be fragile in maintenance and further development. Therefore, a new version of EduSof has been designed, considering a new model of ITS we developed using object-oriented approach. It is called GET- BITS (GEneric Tools for Building ITSs), and is essentially a specific extension of a more general, recently developed model of knowledge bases, called OBOA [7, 8] (OBject-Oriented Abstraction). First, we introduced the control knowledge of an ITS. The control knowledge describes the ITSs problem-solving process, reasoning strategies used by the inference engine, organizational hierarchy of reasoning modules and agents, control regimes corresponding to particular steps of the problem-solving task, the methods of elaborating the answers, etc. To an extent, this knowledge complements the domain knowledge - ideally, control knowledge is an application-independent description of how the problem-solving and reasoning activities are performed during the various ITSs operation, i.e. during the learning process. The same is with the all modern Expert Systems (ES), which have both domain and control knowledge represented in their knowledge bases explicitly. This paper describes how control knowledge is treated by a recently developed object-oriented model of ITSs knowledge bases. The model covers all essential aspects of control knowledge, such as generic tasks, control procedures, meta-reasoning, inference paradigms, etc. All these aspects are covered in an object-