CHAD-KG: A Knowledge Graph for Representing Cultural Heritage Objects and Digitisation Paradata

This paper introduces the Cultural Heritage Acquisition and Digitization Knowledge Graph (CHAD-KG), a knowledge graph (KG) for describing bibliographic metadata and digitization paradata of cultural heritage objects in exhibitions, museums, and collections. Built from two tabular datasets, the data were transformed into the Resource Description Framework (RDF) using CHAD-AP, a Web Ontology Language (OWL) application profile based on standards such as the International Committee for Documentation Conceptual Reference Model (CIDOC-CRM), the Object-Oriented Library Reference Model (LRMoo), the Conceptual Reference Model for provenance metadata (CRMdig), and the Getty Art & Architecture Thesaurus (AAT). Then, a Morph-Knowledge Graph Construction (Morph-KGC) extension allowed the graph's materialization. Unlike many existing cultural heritage KGs, CHAD-KG placed digitization events and paradata at the core of its semantic model and offers an openly available, modular pipeline for KG generation. The current release (v1.0) contains 66,294 RDF triples, serves as the main metadata source for the digital twin of the exhibition The Other Renaissance – Ulisse Aldrovandi and The Wonders of the World, and supports related digitization work in the national Cultural Heritage Active Innovation for Next Gen Sustainable Society (CHANGES) project. It offers a SPARQL endpoint, a user interface, documentation, and is openly published on Zenodo under a CC0 waiver. The project enhanced semantic interoperability in cultural heritage data.