Administrative Role Based Access Control (ARBAC) is one of the most widespread framework for the management of access-control policies. Several automated analysis techniques have been proposed to help maintaining desirable security properties of ARBAC policies. One of the main limitation of available analysis techniques is that the set of users is bounded. In this paper, we propose a symbolic f...

Cheating and plagiarism can involve the transgression of intellectual property rights across many areas of life. When a direct financial benefit from such practices is identifiable, the opportunity to seek legal redress is available via civil court action. When it is undertaken by a public official it may constitute malfeasance. Yet in the case of breaches of university regulations (from the gr...

What is the impact of surprise and anticipated policy changes when agents form expectations using adaptive learning rather than rational expectations? We examine this issue using the standard stochastic real business cycle model with lump-sum taxes. Agents combine knowledge about future policy with econometric forecasts of future wages and interest rates. Dynamics under learning can have large ...

There is a large body of work on the evolution of graphs in various domains, which shows that many real graphs evolve in a similar manner. In this paper we study a novel type of network formed by mentor-apprentice relationships in a massively multiplayer online role playing game. We observe that some of the static and dynamic laws which have been observed in many other real world networks are n...

This article presents the idea of defining a kernel for object role modelling techniques, upon which different drawing styles can be based. We propose such a kernel (the ORM kernel) and define, as a case study, an ER and a NIAM drawing style on top of it. One of the prominent advantages of such a kernel is the possibility to build a CASE-tool supporting multiple methods. Such a CASE-tool would ...

One difficult task in information modeling is to adequately address the impact of time. This paper briefly reviews some popular approaches for modeling temporal data and operations, then provides a conceptual framework for classifying temporal information, and proposes data model patterns to address time-impacted tasks such as modeling histories, and tracking entities across time as they migrat...

Access Control is a technique which insures security by preserving confidentiality and integrity of information. Meca (Models for access control) is a tool which generates, in a B machine, operational conditions that should be verified by an application to insure security. The inputs of Meca are a B machine offering a format for presenting a security model and a functional model containing the ...

background the present study was conducted to perceive the role-model nursing instructors’ experience in terms of professional challenges and identification of occupational concerns in the education of nursing students. nursing instructors have a critical and decisive role in the training of skilled and specialized manpower and subsequent growth and development of the communities. so, the prese...