We consider the problem of defining an approximation measure for functional dependencies (FDs). An approximation measure for X → Y is a function mapping relation instances, r, to non-negative real numbers. The number to which r is mapped, intuitively, describes the “degree” to which the dependency X → Y holds in r. We develop a set of axioms for measures based on the following intuition. The de...

Functional amnesia, also known as dissociative psychogenic or mnestic block syndrome, is a rare disorder which, although clinically heterogeneous, most often characterised by dense retrograde amnesia mainly affecting the episodic-autobiographical domain but with relative preservation of anterograde memory function, pattern dissimilar to that seen in other amnesic disorders. The pathogenesis fun...

Requirements specification methods and techniques have hitherto mainly been concerned with promoting various representation formalisms for formally describing information systems, and discussing their expressive power. However, this approach concentrates only partially on the problem. A major issue is how to bridge the gap between ill-defined problem and application situations, and specificatio...

A considerable number of methods and tools have been proposed for the treatment of non-functional requirements (NFRs). There is ample evidence that NFRs play a significant role in the Information Systems Engineering process. However, there is surprisingly an absence of an agreed position regarding the definition of NFRs, their classification and presentation. This paper reports on a systematic ...

This case study examines an often overlooked context of information system failures, that of preimplementation failure. It focuses on an Information Systems Development (ISD) project at a large public university that failed even before implementation could get under way. Specifically, it describes the vendor selection process of a proposed computerized maintenance management system. While the m...

nformation processing in the primate brain is based on the complementary principles of modular and distributed information rocessing. The former emphasizes the specialization of functions within different brain areas. The latter emphasizes the massively arallel nature of brain networks and the fact that function also emerges from the flow of information between brain areas. The ocalization of f...

This paper presents a framework for verifying compilation tools for parametrised hardware libraries with placement information. Such libraries are captured in Pebble, a simple declarative language based on Structural VHDL, and can contain placement information to guide circuit layout. Relative placement information enables control of circuit layout at a higher level of abstraction than placemen...