Ralf Jungclaus

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TROLL is a language particularly suited for the early stages of information system development, when the universe of discourse must be described. In TROLL the descriptions of the static and dynamic aspects of entities are integrated into object descriptions. Sublanguages for data terms, for first-order and temporal assertions, and for processes, are used to(More)
Conceptual modelling, sometimes in conjunction with requirements acquisition, is widely accepted as the rst formal step in information system speciication and design. Since knowledge about the world to be modelled is often vague in early development phases, formalisms for conceptual modelling must support a wide variety of concepts for describing real(More)
The conceptual modeling of the Universe of Discourse (UoD) is an important phase for the development of information systems because the conceptual model is the basis for system development. Conceptual model speciications must be formal in order to be precise and unambiguous and to support consistency and completeness checks. The object-oriented paradigm is(More)
Most object-oriented databases can only be accessed by a programming language rather than a query language, although an ad hoc query facility is a desirable feature of such systems. In this paper, we present a way to process queries to extract data from a collection of interacting objects. We adopt the object-oriented paradigm to describe the operational(More)