A proposal for extending UML-B to support a conceptual model

UML-B is a development process framework for Event-B based on a "UML-like" graphical formal notation that provides support for object-oriented modelling concepts, in particular, for class and state machine diagrams. However, this methodology has a gap for mapping requirements to formal specifications. To overcome this issue, we present a proposal for extending UML-B to support a conceptual model to provide an easier starting point for the actual development process. More precisely, we propose two diagrams to facilitate the passing from requirements to the initial formal model: a first one to represent system behavior based on UML 2 interaction overview diagram (IOD) and a second one for system structure based on boundary-control-entity stereotyped class diagram (BCE). We show how to translate the former into an Event-B specification and explain how to link the latter to the original UML-B using a simple ATM example as proof of concept.