An RDF graph is, at its core, just a set of statements consisting of subjects, predicates and objects. Nevertheless, since its inception practitioners have asked for richer data structures such as containers (for open lists, sets and bags), collections (for closed lists) and reification (for quoting and provenance). Though this desire has been addressed in the RDF primer and RDF Schema specific...

We review the definition of entity types derived by symbolgenerating rules. These types appear frequently in conceptual schemas. However, up to now they have received very little attention in the field of conceptual modeling of information systems. Most conceptual modeling languages, like the UML and ORM, do not allow their formal definition. In this paper, we propose a new method for the defin...

With societal security, the Copenhagen school has provided a concept that illuminates much of the conflict between states and sub-state groups, though, as their critics have pointed out, the danger of reifying the identity of these groups is all too real. How can the concept be employed without succumbing to the weaknesses associated with the reification of societal identity. This paper examine...

Motivated by the close relation between real-time and fault tolerance, we investigate the foundations of a forma! framework to specify and verify real-time distributed systems that incorporate fault tolerance techniques. Therefore a denotational semantics is presented to describe the real-time behaviour of distributed programs in which concurrent processes communicate by synchronous messa.ge pa...

Motivated by the close relation between real-time and fault tolerance, we investigate the foundations of a forma! framework to specify and verify real-time distributed systems that incorporate fault tolerance techniques. Therefore a denotational semantics is presented to describe the real-time behaviour of distributed programs in which concurrent processes communicate by synchronous messa.ge pa...

Data rei cation normally involves the explicit positing of an abstraction function with certain properties. However, the condition for one de nition to reify another only requires that a function with such properties should exist. This suggests that it may be possible to carry through a data rei cation without giving an explicit de nition of the abstraction function at all. This paper explores ...

Linearity is a multi-faceted and ubiquitous notion in the analysis and the development of programming language concepts. We study linearity in a denotational perspective by picking out programs that correspond to linear functions between domains. We propose a PCF-like language imposing linear constraints on the use of variable to program only linear functions. To entail a full abstraction resul...

In this article we introduce the basics for understanding the mechanisms of Argument Theory Change. In particular we reify it using Defeasible Logic Programming. In this formalism, knowledge bases are represented through defeasible logic programs. The main change operation we define over a defeasible logic program is a special kind of revision that inserts a new argument and then modifies the r...

Motivated by the close relation between real-time and fault tolerance, we investigate the foundations of a forma! framework to specify and verify real-time distributed systems that incorporate fault tolerance techniques. Therefore a denotational semantics is presented to describe the real-time behaviour of distributed programs in which concurrent processes communicate by synchronous messa.ge pa...