Model transformation is a key technology in modeldriven engineering. Unfortunately, transformations are typically written manually and thus they are likely to contain errors and to produce incorrect or undesired output. Safe transformation is the guarantee that for every possible source model, the transformed target model is valid with respect to user-definable wellformedness criteria. This pap...

For assessing conceptual data model quality it is useful to have quantitative and objective measurement instruments. The scarcity of such measurement instruments leaded us to define a set of measures for structural complexity, an internal quality attribute of conceptual data models, with the idea that it is related to the external quality of such models. In order to gather empirical evidence th...

We propose a set of operations for inquiring about the properties of individual objects and classes in an object-oriented database. The operations are closely related to the constructs introduced by our formalisa-tion of the object-oriented data model, through which we unify the representation of the intensional and the extensional portions of the object-oriented database. As a consequence, the...

In this paper, we present a conceptual data model for multimedia database applications based on ExIFO2 model. The ExIFO2 data model is chosen as the conceptual model since it handles both complex objects along with their uncertain and imprecise properties. We enhanced this conceptual model in order to meet the multimedia data requirements. In addition to uncertain and imprecise information, we ...

Die etablierte Dokumentationspraxis von Sammlungsobjekten in Museen erfolgt vorrangig auf Grundlage einfacher Datenfelder (Karteikartenmodell). Der hier verfolgte methodische Ansatz bezieht die Darstellung von Prozessen bzw. deren Ereignissen mit ein. Das CIDOC „Conceptual Reference Model“ (ISO 21127) wurde als Referenzontologie, das sog. „Erlangen CRM / OWL“ umgesetzt. Auf Basis dieser in OWL ...

This paper presents an architecture for managing database evolution when all the components of the database (conceptual schema, logical schema and extension) are available. The strategy of evolution in which our architecture is based is that of ‘forward database maintenance’, that is, changes are applied to the conceptual schema and propagated automatically down to the logical schema and to the...

This study explores the differences between conceptual data models designed by expert and novice data modelling practitioners. The data models are evaluated using a number of quality factors synthesised from previous empirical studies and frameworks for quality in conceptual modelling. This study extends previous studies by using practitioners as participants and using a number of different qua...

The focus of this paper is database design in the context of converting a conceptual data model into an internal representation. For a given conceptual data model, an access pro-le speciies statistical information about (retrieval and update) requests to be performed, while a data proole speciies a statistical characterization of the database contents. The corresponding time/space trade-oo and ...

Conceptual change is a popular, contemporary conception of meaningful learning. Conceptual change describes changes in conceptual frameworks (mental models or personal theories) that learners construct to comprehend phenomena. Different theories of conceptual change describe the reorganization of conceptual frameworks that results from different forms of activity. We argue that learners’ concep...

A method for obtaining optimized relational representations of database conceptual schemas in an extended entity-relationship model is first proposed. The method incorporates and generalizes a familiar heuristics to obtain good relational representations and also produces, for each relational structure, an explanation indicating which concepts it represents. Then, a redesign method that, given ...