The Centre for Digital Built Britain has been tasked through the Digital Framework Task Group to develop an Information Management Framework (IMF) to support the development of a National Digital Twin (NDT) as set out in “The Pathway to an Information Management Framework” (Hetherington, 2020). A key component of the IMF is a Foundation Data Model (FDM), built upon a top-level ontology (TLO), as a basis for ensuring consistent data across the NDT.

This document captures the results collected from a broad survey of top-level ontologies, conducted by the IMF technical team. It focuses on the core ontological choices made in their foundations and the pragmatic engineering consequences these have on how the ontologies can be applied and further scaled. This document will provide the basis for discussions on a suitable TLO for the FDM. It is also expected that these top-level ontologies will provide a resource whose components can be harvested and adapted for inclusion in the FDM.

Following the publication of this document, the programme will perform a structured assessment of the TLOs identified herein, with a view to selecting one or more TLOs that will form the kernel around which the FDM will evolve. A further report – The FDM TLO Selection Paper – will be issued to describe this process in late 2020.

The review of existing industry data models and reference data libraries will support the development of the National Digital Twin Information Management Framework. The review will have different roles during the development. The envisaged roles are as follows:

- existing industry data models and reference data libraries are identified

- the structure of the models and libraries is summarised

- the extensibility of the models is described

- the documentation of the models is described

- the maintenance and usage of the models is described

The purpose of this report is to give an understanding of the technicalities of the foundation and formalisation underpinning a foundational ontology.

This report is directed at a technical audience interested in understanding what the foundation of the foundational ontology is and how it is formalised. In particular, we expect the report to be of interest to logicians and formal ontologists.

This is part of a project to build a unified foundation, called the Core Constructional Ontology (CCO). This stage of the project has developed a transitional framework that establishes the feasibility of building the CCO. The framework is formalised by means of a theory we call the Core Constructional Theory (CCT). Here we describe the CCT and its associated CCO. Later stages of the project will further develop and enhance this framework. Appendix E.5 gives some indication of what these enhancements could be. This novel theory develops the idea that all the objects in the CCO emerge during construction. We start from an initial collection of objects—often called givens—and a small number of constructors, and the entire ontology unfolds from repeated constructions. So from the givens and constructors one knows, in principle, all the objects in the ontology. Using the technical resources of plural logic, the CCT formalises the arrangement of constructions in stages, where the intended ontology arises after exhausting all the stages. This report documents the CCT and provides a proof of its consistency.