The need of diagrams based on Toulmin schema application: an aeronautical case study

In this article, justification diagrams are introduced for structuring evidence to support conclusions that are reached from results of simulation studies. An industrial application is used to illustrate the use of the justification diagrams. Adapted from the Toulmin schema, the aim of justification diagram is to define a comprehensive, auditable and shareable notation to explain the results, the input data, the assumptions made and the techniques applied, to construct a cogent conclusion. Further, the dustification diagrams provide a visual representation of the argument that aims to corroborate the specified claims, or conclusions. A large part of this work is based on the application of the justification diagrams in the context of the European project, TOICA. The justification diagrams were used to structure all justifications that would be needed to convince an authority that a simulation process, and the associated results, upheld a particular conclusion. These diagrams are built concurrently in a product development process that accompanies the various stages of Verification and Validation (V&V) and where, for each design stage of V&V, argumentation is constructed by aggregating evidence and documents produced at this design stage.