Introduction

The National Research Data Infrastructure (NFDI) initiative initiative has led to the formation of various consortia, each focused on developing a research data infrastructure tailored to its specific domain. To ensure interoperability across these consortia, the NFDIcore ontology has been developed as a mid-level ontology for representing metadata related to NFDI resources, including individuals, organizations, projects, data portals, and more.

In line with NFDI's goals, this ontology has been created to provide a structured framework that enables efficient management, organization, and interconnection of research data across various disciplines. By adhering to established data standards, the ontology facilitates the accessibility, sharing, and reuse of research data in a consistent and sustainable manner.

The key features of the NFDIcore ontology are:

  • Representation of the NFDI Structure: The ontology models the organizational structure of NFDI, including its components, projects, services, and partnerships.

  • Referencing Partner Data: It enables the description and reference of data from various NFDI project partners, providing a unified framework for organizing and linking research data across disciplines.

  • Standardization and Interoperability: By adhering to data management standards, the ontology ensures that data from different sources can be interconnected, shared, and reused.

Recognizing the diverse needs of consortia, NFDIcore is built upon the Basic Formal Ontology (BFO), a foundational framework essential for enhancing knowledge representation, data exchange, and interdisciplinary collaboration. To address domain-specific research questions, NFDIcore serves as the basis for various application and domain ontologies, which extend its core structure in a modular fashion. Examples include the NFDI4Culture Ontology (CTO), NFDI MatWerk Ontology (MWO), NFDI4Memory Ontology (MEMO), and NFDI4DataScience Ontology (DSO), each tailored to specific research fields while ensuring semantic interoperability.

As a mid-level ontology, NFDIcore plays a central role in structuring and integrating research data across consortia. It provides a shared vocabulary that represents both the organizational structure of the NFDI and the diverse datasets contributed by project partners. The ontology encompasses key concepts such as organizations, consortia, projects, datasets, research outputs, geographical locations, and technical standards. These structured representations enable efficient data management, integration, and reuse across disciplines.

NFDIcore focuses on describing the following main concepts:

  • Organizational & Research Structure – Represents institutions, consortia, projects, researchers, and their roles within NFDI.
  • Data & Information Management – Covers datasets, data portals, collections, publications, and intellectual outputs to support research.
  • Geographical & Contextual Information – Includes cities, countries, and regions relevant to NFDI activities.
  • Technology & Standards – Encompasses software, programming languages, specifications, standards, and ontologies for interoperability.
  • Services & Licensing – Defines resources, service processes, licenses, and web-based platforms supporting data sharing and collaboration.