Access control in distributed systems is a complex problem that can be tackled in several ways. The XACML standard provides a possible solution, with several benefits and some drawbacks. In this paper we investigate the concepts behind distributed access control, review the XACML standard, and provide practical suggestions about the components to be used in building a XACML-based distributed ac...

This paper describes one university’s approach to improving the quality of teaching and learning at the institutional level, based on the premise of improving the design of curriculum rather than focusing on the skills of teachers as such. The paper describes the process by which university-wide principles of curriculum design were defined and agreed, as well as the parallel campaigns needed to...

This paper describes interchange formats as an important subject of standardization. Building on reported experiences of interchange format design in specific domains, a list of design criteria is gathered addressing both the conception of the metamodel behind the interchange format and the serial representation.

Niklaus Wirth is not only a master of language design but also a pioneer of compiler construction. For four decades he has refined his techniques for building simple, efficient and reliable compilers. This paper tries to collect some general principles behind his work. It is not a paper about new compilation techniques but a reflection about Wirth's way to write compilers.

In this talk I will review the present status of inflationary cosmology and its emergence as the basic paradigm behind the Standard Cosmological Model, with parameters determined today at better than 10% level from CMB and LSS observations. I will also discuss the recent theoretical developments on the process of reheating after inflation and model building based on string theory and D-branes.

We study a semi-implicit time-difference scheme for magnetohydrodynamics of a viscous and resistive incompressible fluid in a bounded smooth domain with perfectly conducting boundary. In the scheme, velocity and magnetic fields are updated by solving simple Helmholtz equations. Pressure is treated explicitly in time, by solving Poisson equations corresponding to a recently developed formula for...

This paper explores, through a number of case studies, the application of Group Support Systems for capacity building initiatives in various sectors in Africa. A model is introduced on the adoption of GSS in an African context. Notwithstanding skeptical expectations with respect to the successful application of the technology, the results clearly indicate (1) that there is support from key part...

Recent signijkant advances in artijicial intelligence have led to the emergence of new concepts of soji computing genetic programming, evolutionary engineering, hybrid intelligent systems, and artijicial life. EE design relies on evolutionary algorithms to construct or evolve complex systems. This paper is intended to highlight the concept of evolutionaly engineering, the motivations behind the...

In this position paper we analyze the similarities amongst folksonomies, semantic wikis, and ontology building; we also propose an alignment and orchestration of ontologies representing these scenarios. We argue that such alignment enables a more direct application of folksonomybased approaches over these set-ups. The rationale behind folksonomies is shared across environments such as collabora...

In this work we introduce the system for adaptive practice of foundations of mathematics. Adaptivity of the system is primarily provided by selection of suitable tasks, which uses information from a domain model and a student model. The domain model does not use prerequisites but works with splitting skills to more concrete sub-skills. The student model builds on variation of Elo rating system ...