This paper introduces the notion of safety and availability checking for user authorization query processing, and develop a recursive algorithm use the ideas from backtracking-based search techniques to search for the optimal solution. For the availability checking, we introduce the notion of max activatable set (MAS), and show formally how MAS can be determined in a hybrid role hierarchy. For ...

Access control is a difficult security issue for enterprise organizations. Role-based access control (RBAC) model is well known and recognized as a good security model for enterprise environment. Though RBAC is a good model, administration of RBAC including building and maintaining access control information remains a difficult problem in large companies. RBAC model itself does not tell the sol...

Test situations evoke anxiety for many when the impact of tests on one’s life is considered, including the educational, emotional and other aspects. The purpose of this study is to examine the mediating role of emotion-focused and avoidant coping strategies on the relationship between trait anxiety and test anxiety. 375 high students (193 males, 182 females) aged 15-18 were selected by ra...

We demonstrate how one can use the formal concept analysis (FCA) to obtain the role hierarchy for the role based access control from the existing access control matrix. We also discuss assesed by means of FCA the quality of security system and finding users with excess permissions.

In every communicative context, each participant assumes some kind of role and negotiates some type of relationship with their counterparts. In the e-learning domain, the roles (e.g. instructor, learner, marker, administrator, etc.) for participants are well structured and relationships (e.g. one-to-one, one-to-many, hierarchical, etc.) among roles are relatively predictable. This paper propose...