Abstract
Archives have well-established description standards, namely the ISAD(G) and ISAAR(CPF) with a hierarchical structure adapted to the nature of archival assets. However, as archives connect to a growing diversity of data, they aim to make their representations more apt to the so-called linked data cloud. The corresponding move from hierarchical, ISAD-conforming descriptions to graph counterparts requires state-of-the-art technologies, data models and vocabularies. Our approach addresses this problem from two perspectives. The first concerns the data model and description vocabularies, as we adopt and build upon the CIDOC-CRM standard. The second is the choice of technologies to support a knowledge graph, including a graph database and an Object Graph Mapping library. The case study is the Portuguese National Archives, Torre do Tombo, and the overall goal is to build a CIDOC-CRM-compliant system for document description and retrieval, to be used by professionals and the public. The early stages described here include the design of the core data model for archival records represented as the ArchOnto ontology and its embodiment in the ArchGraph knowledge graph. The goal of a semantic archival information system will be pursued in the migration of existing records to the richer representation and the development of applications supported on the graph.

Abstract
Archives are faced with great challenges due to the vast amounts of data they have to curate. New data models are required, and work is underway. The International Council on Archives is creating the RiC-CM (Records in Context), and there is a long line of work in museums with the CIDOC-CRM (CIDOC Conceptual Reference Model). Both models are based on ontologies to represent cultural heritage data and link them to other information. The Portuguese National Archives hold a collection with over 3.5 million metadata records, described with the ISAD(G) standard. The archives are designing a new linked data model and a technological platform with applications for archive contributors, archivists, and the public. The current work extends CIDOC-CRM into ArchOnto, an ontology-based model for archives. The model defines the relevant archival entities and properties and will be used to migrate existing records. ArchOnto accommodates the existing ISAD(G) information and takes into account its implementation with current technologies. The model is evaluated with records from representative fonds. After the test on these samples, the model is ready to be populated with the semi-automatic transformation of the ISAD records. The evaluation of the model and the population strategies will proceed with experiments involving professional and lay users.

Abstract
This paper presents an automatic semantic migration prototype based on Knowledge Discovery from Digital Archive Data for ontology population in the domain of Archives metadata, ISAD(G). Natural Language Processing (NLP) techniques are used for language processing and Semantic Web techniques for querying and updating the Ontology ArchOnto, a CIDOC-CRM (Conceptual Reference Model) extension. This work is done in the context of project EPISA (Entity and Property Inference for Semantic Archives) where the Portuguese National Archives, Torre do Tombo (ANTT) is one of the partners. The data model and description vocabularies we adopted are built upon the CIDOC-CRM standard, an ontology, developed for museums by the International Committee for Documentation (CIDOC) of the International Council of Museums (ICOM). A detailed example of a baptism document metadata migration is presented to highlight the challenges on the natural language interpretation and the ontology representation.

Abstract
Incorporating linked data-based models into the process of describing cultural objects is increasingly important for cultural heritage. Communities such as libraries, archives, and museums have developed and adopted models specific to their contexts. Without a trivial solution, choosing models to support more general applications is challenging. This Ph.D. aims to analyze existing solutions and practices in these domains and propose validated solutions for the discovery, access, interoperability, and reuse of cultural objects, following the FAIR principles. Transversal to the base models used, this research intends to adopt solutions that balance the simplicity of the models with the satisfaction of the requirements.

Abstract
PurposeThis study aims to comparatively evaluate two semantic models, ArchOnto (CIDOC CRM based) and Records in Contexts Ontology (RiC-O), for archival representation within the Linked Open Data framework. The research seeks to critically analyse their ability to represent archival documents, events, activities, and provenance through the application on a case study of historical baptism records.Design/methodology/approachThe study adopted a comparative approach, utilising the two models to represent a dataset of baptism records from a Portuguese parish spanning several centuries. This involved information extraction and conversion processes, transforming XML EAD finding aids into RDF to facilitate more explicit semantic representation and analysis.FindingsThe analysis revealed distinctive strengths and limitations of each semantic model, providing nuanced insights into their respective capacities for archival description. The findings guide cultural heritage institutions in selecting and implementing the most suitable semantic model for their needs and pave the way for semantic alignment between the two models.Research limitations/implicationsAlthough the case study explored the representation of a wide range of features, potential limitations include the specific contextual constraints of parish records and the need for broader comparative studies across diverse archival contexts.Originality/valueThis paper offers original insights into semantic modelling for archival representations by providing a detailed comparative analysis of two ontological approaches. It offers valuable perspectives for archivists, digital humanities researchers, and cultural heritage professionals seeking to enhance the semantic richness of archival descriptions.

Abstract