Use cases are the notation of choice for functional requirements documentation, whereas task models are used as a starting point for user interface design. In this paper, we motivate the need for an integrated development methodology in order to narrow the conceptual gap between software engineering and user interface design. This methodology rests upon a common semantic framework for developin...

Schobbens, P.-Y., Exceptions for algebraic specifications: on the meaning of “but”, Science of Computer Programming 20 (1993) 73-111. When building large specifications from requirements, the structure of the specification becomes a central problem: the specification language should allow a decomposition that closely reflects the structure of requirements. In this paper, we propose a decomposit...

‎Based on a definition for circle in Finsler space‎, ‎recently proposed by one of the present authors and Z‎. ‎Shen‎, ‎a natural definition of extrinsic sphere in Finsler geometry is given and it is shown that a connected submanifold of a Finsler manifold is totally umbilical and has non-zero parallel mean curvature vector field‎, ‎if and only if its circles coincide with circles of the ambient...