This paper is a contribution to the formal study and analysis of vernacular forms of program derivation. Specifically, in this paper, our vernacular derivations are elementary program transformations over the natural numbers. We provide an intensional semantics for these transformations within the derivations of the Elementary theory of Operations and Numbers, EON, [Bee85]. This semantics is in...

This paper presents a new metamodel based on partially ordered hypersets. The metamodel is minimalist, its only primitives being atoms, potentially infinite hypersets and partial order. The type system is very loose and supports concurrent extensional and intensional definition of types. Every element of the metamodel can be directly referenced, thanks to a powerful automated reification facili...

The term 'model' often describes non-human biological systems that are used to obtain a better understanding of human disorders. According to the most stringent definition, an animal 'model' would display exactly the same phenotype as seen in the relevant human disorder; however, this precise correspondence is often not present. In this Editorial, I propose the alternative, broader term 'tool' ...

The specifications of automated learning scenarios can lead to advantages for virtual learning environments and important benefits for organizations, although research in this e-learning area has not addressed this issue. To achieve this goal, one requirement is to have an infrastructure able to support the execution of specifications of learning scenarios. This paper presents an open service-o...

We describe a logic language to formally express interdependencies between classes belonging to different schemas, the socalled interschema knowledge. These interdependencies allow a designer of a multidatabase (MDB) to establish relationships between both the intensional definition and the set of instances of classes represented in different schemas. These assertions form the „backbone“ of the...