An algebra for geometric conceptual modelling
Authors 
Hui Ma KlausDieter Schewe 
Editors 

Title  An algebra for geometric conceptual modelling 
Booktitle  Electronic Proceedings of the 23rd European Japanese Conference on Information Modelling and Knowledge Bases (EJC 2013) 
Type  in proceedings 
Month  June 
Year  2013 
Pages  184202 
Abstract  The geometrically enhanced ER model (GERM) addresses conceptual geometric modelling on two levels. On the surface level GERM is an extended ER model, in which attributes are associated with types with sets of values as domains. On the internal level some of the types, the geometric types, are further associated with geometric domains, which define point sets by means of algebraic curves. In this paper we complement GERM by an algebra to support querying and updates. In this algebra operations on geometric types give rise to operations on point sets, which can be realized by a small set of Boolean operations on algebraic curves. The core problem for such an algebra on a conceptual model is to obtain a surface representation as the result. We show how this can be achieved by means of symbolic computation. 