“…Other research efforts in the field do not make the separation between assembly and object and have both kinds of information integrated within a single representation (see, for example, the component-based building representation effort by Harfmann & Chen 1993). In contrast, we have found that by separating the components (objects) from the assemblies in which they are used, we can simplify both representations (of the assemblies and the components), and make the databases easier to implement and to maintain.…”