Knowledge Representation in a Learning Environment for Euclidean Geometry*

Maria Alberta Alberti and Daniele Marini


Virtual laboratories uncover some new problems of system and interface design, b ecause they can induce misleading mental images of the subject matter. Rooting a system design on the a nalysis of the knowledge domain allows a clean internal design. Object-oriented methodology to represent the geometric knowledge and Petri nets formalism to represent geometric constructions helped us to solve the conceptual problem of formalising the knowledge structure, minimising inconsistencies between the content matter and i ts representation. The prototypal system implemented adopts a "programming by example" paradigm to incrementally enrich construction methods; new constructions can be used to define new classes of objects or new methods fo r an existing class.

* This work has been financially supported by M.U.R.S.T., Ministero per l'Università e la Ricerca Scientifica e Tecnologica, Italy.


luglio 94, M.A.Alberti,
alberti@dsi.unimi.it