OBJECT-ORIENTED REPRESENTATION OF QUALITATIVE ENGINEERING PROPERTIES

The paper presents objections to the prevailing record-oriented data m odelling of physical-world properties of use to engineering design. Th e limitations, which produce an oversimplification in the representati on of property information, are highlighted in relation to software sy stems for materials selection. The overarching problem lies in the hig hly context-specific way in which properties of materials and engineer ing products need to be interpreted. By way of redress, two techniques are presented which are supported by a special object-oriented langua ge devised to process design descriptions. The first technique provide s a representation of properties of families of materials as distribut ions of numerical values within ranges which are automatically generat ed by family members. The second technique involves treating qualitati vely described properties as agglomerations of property features compo unded or together. Both techniques are supported by a special language specification of complex prototypical objects which depict the proper ties of any given entity themselves as entities.