ArchOnto 1.0

Working Version, January 2025

This version: https://purl.org/episa/archonto/1.0

Latest version: https://purl.org/episa/archonto

Previous version: https://purl.org/episa/archonto/0.9

Editor: Inês Koch

Abstract

This specification describes ArchOnto, a linked open data model. ArchOnto adopts a semantic web approach and encompasses the CIDOC Conceptual Reference Model and additional ontologies, envisioning interoperability with datasets curated by multiple communities of practice. Its goal is to serve as the foundation for the development of a knowledge graph prototype and new applications for the archives.

Status of this document

This document is in progress. This may undergo changes considering that the present ontology is in constant development.

Currently, the ArchOnto can already represent the description of archival records, identifying people, places, dates, and related events. In the future, the ontology will represent the digital representations associated with each document already described through ArchOnto.

The ArchOnto specification is produced as part of the Entity and Property Inference for Semantic Archives (EPISA) project at INESC TEC to provide authoritative documentation of the contents, status and purpose of the linked data model known as ‘ArchOnto’. Furthermore, this ontology fits into Inês Koch’s doctoral thesis project.

Table of Contents

• Glossary
• 1. Introduction
• 2. Architecture
• 3. Classes and Properties
  • ArchOnto
  • DataObject
  • CIDOC CRM Main
  • CIDOC CRM PC
  • ISAD Ontology
  • Link2DataObject

Glossary

ArchOnto

• Ontology created in the context of archives as an extension to CIDOC CRM.
• Uses the prefixes:
  • ARE – Archival Entity, eg.: ARE1 Level of Description.
  • ARP – Archival Property, eg.: APR12 has level of description.

CIDOC CRM – CIDOC Conceptual Reference Model

• Reference ontology, designed to facilitate the integration, mediation and exchange of information in the field of cultural heritage.
• Provides the semantic definitions and rules needed to transform fonts.
• localized and disparate information into a coherent global resource.
• CRM intends to serve as a reference in terms of concepts and, therefore, of semantics to database schemas and organizational structures of
• documents in various information systems.
• Use the prefixes:
  • E – Entity, eg.: E1 CRM Entity;
  • P – Property, eg.: P1 is identified by

CIDOC CRM PC

• CIDOC CRM ontology created to represent typed properties with an arity higher than two.

• Ontology that served as the basis for the creation of the N-ary ontology and, as of version 1.0, replaces it.

• Use the prefixes:

  • PC – Entity, eg.: PC14 carried out by;
  • P – Property, eg.: P01 has domain

DataObject

• Ontology created in order to validate literal values used in properties of the newly created data model.

• It has classes and data properties in its base that are used to validate data from simple types in the ontology, ensuring class-based validation.

• Use the prefixes:

  • DOE – Data Object Entity, eg.: DOE1 Data Object;
  • DOP – Data Object Property, eg.: DOP1 approximate date value

ISAD(G) - General International Standard for Archival Description

• Establishes general guidelines for the preparation of archival descriptions that can be applied to any type of document, regardless of its dimension, shape or support.

ISAD Ontology

• Ontology created to represent all fields of the ISAD(G) standard;

• It has Data Properties in its base that allow the incorporation of all fields ISAD(G). With this ontology, the information of archival descriptions is kept existing files created over the years by the various archives at the national level.

• The ontology allows, whenever necessary, the validation of the contents that were atomized, verifying if they are in accordance with the registration that already existed in the ISAD(G) description.

• All information associated with a unit of description is considered as a physical object; in CIDOC CRM there are attributes associated with the physical object and others with the conceptual object. In this ontology, it is assumed that the physical object incorporates the conceptual object.

• With this ontology it will be possible to maintain the interoperability of all data represented in ISAD(G).

• Use the prefixes:

  • ISAD – ISAD Property, eg.: ISAD1 has title

Link2DataObject

• Ontology created to link the CIDOC CRM ontology with the ontology DataObject.
• Imports both ontologies and has an object property that allows to link the two imported ontologies – L2DO has value.

1. Introduction

ArchOnto is the name of the new model supporting the representation of assets at DGLAB (Direção-Geral do Livro, dos Arquivos e das Bibliotecas). Its goal is to serve as the foundation for developing a knowledge graph prototype and new applications for the archives.

ArchOnto is a modular data model that integrates five ontologies, dealing with complementary aspects of the archival domain. The five ontologies are CIDOC CRM Main (base ontology), CIDOC CRM PC, DataObject, ISAD Ontology, and Link2DataObject. ArchOnto also has its classes and properties.

In the figure below there is an application example of ArchOnto ontology.

Figure 1. ArchOnto Application Example

2. Architecture

ArchOnto is a modular data model that integrates five ontologies, dealing with complementary aspects of the archival domain, as illustrated in Figure 2. The five ontologies are:

• CIDOC CRM (base ontology): the core of ArchOnto, providing the concepts and properties to capture archival records’ essential features, e.g., event, date, location, person, group.

• CIDOC CRM PC: systematically represents non-binary associations, i.e., those that connect more than two individuals. Representing a person’s role in a given event is an example of this kind of association because it involves relating an event, a person, and a role.

• DataObject: auxiliary ontology to deal with literal values and their validation in ArchOnto. Comprises classes and data properties for the simple types in the ontology. In this ontology, the names of classes are preceded by DOE (from DataObject Entity), and the names of properties are preceded by DOP (from DataObject Property).

• ISAD Ontology: matches the ISAD(G) standard elements that can be directly obtained from existing records. The information is represented with Data Properties and is not atomized. The ontology can be regarded as an intermediate representation for legacy records, making it possible, whenever necessary, to check the contents of a given element against the information extracted thereof. This ontology is only used for the existing records in DigitArq and not for newly created records based on ArchOnto.

• Link2DataObject: makes the connection between the CIDOC CRM and the DataObject ontologies with a single property to make this connection — L2DO hasValue.

In addition to these five ontologies, ArchOnto has its own classes and properties, created as extensions to CIDOC CRM. Classes are used to specialize concepts already present in CIDOC CRM but which needed to be adapted to include controlled vocabularies that exist in the archives. CIDOC CRM. In addition to these classes, the ontology also includes three properties which provides a control structure for the admissible nesting of units of description. Names for classes are preceded by ARE (from ARchival Entity), and those for properties are preceded by ARP (from ARchival Property).

Figure 2. ArchOnto Architecture

3. Classes and Properties

Full detail regarding each class and property can be found in the following subsections: ArchOnto, DataObject, CIDOC CRM PC, CIDOC CRM Main, ISAD Ontology and Link2DataObject.

Class hierarchy within ArchOnto’s ontologies

Property hierarchy within ArchOnto’s ontologies

ArchOnto

ArchOnto is a modular data model that integrates five ontologies, dealing with complementary aspects of the archival domain. The five ontologies are:

• CIDOC CRM Main (base ontology);
• CIDOC CRM PC;
• DataObject;
• ISAD Ontology;
• Link2DataObject.

Classes

• ARE1 Level of Description
• ARE2 Formal Title
• ARE3 Supplied Title
• ARE4 Extension
• ARE5 Identifier Type
• ARE6 Date Type
• ARE7 Name Type
• ARE8 Role Type
• ARE9 Date Certainty
• ARE11 Documentary Typology
• ARE12 Organisation
• ARE13 Subject Type
• ARE14 Place Type
• ARE15 Acquisition Type
• ARE16 Event Type

ARE3 Supplied Title
The second ISAD(G) element to be considered in the description of a document is its Title, represented in ArchOnto through the ARE2 Formal Title or ARE3 Supplied Title classes. The ARE3 Supplied Title class, a subclass of E35 Title, indicates that the type of title used in the document record is supplied, assigned by an archivist.
URI: https://purl.org/episa/archonto/ARE3
Superclass: E35 Title
Subclasses: -
Related properties: - P102 has title
Example values: - Juízo da Índia e Mina - Mosteiro de São Bernardo de Portalegre - Inventário por óbito de Manuel Joaquim Ferreira Lino

ARE4 Extension
This class allows to indicate the document’s extension in order to distinguish the different uses given to this field.
URI: https://purl.org/episa/archonto/ARE4
Superclass: E54 Dimension
Subclasses: -
Related properties: - P43 has dimension - P90 has value - P91 has unit
Example values: - 13 maços - 21 folhas

ARE5 Identifier Type
ISAD(G) allows several types of identifiers. ARE5 Identifier Type class allows to specify the identifier type. This class is a subclass of E55 Type and is linked to E42 Identifier through the property P2 has type.
URI: https://purl.org/episa/archonto/ARE5
Superclass: E55 Type
Subclasses: -
Related properties: - P2 has type
Example values: - Reference Code - Physical Location - Original Numbering - Previous Location

ARE6 Date Type
This class allows to indicate a date type, which may be a predominant date, of production, death, birth, etc.
URI: https://purl.org/episa/archonto/ARE6
Superclass: E55 Type
Subclasses: -
Related properties: - P2 has type
Example values: - Exact dates - Inferred dates - Predominant dates

ARE7 Name Type
This class allows to indicate a name type, which can be a nickname, last name or last name.
URI: https://purl.org/episa/archonto/ARE7
Superclass: E55 Type
Subclasses: -
Related properties: - P2 has type
Example values: - Authorized form of name - Another Form of the Name - Parallel Name Form

ARE12 Organisation
This class allows to indicate that some activity’s actor is an organisation.
URI: https://purl.org/episa/archonto/ARE12
Superclass: E39 Actor
Subclasses: -
Related properties: - P107 has current or former member (is current or former member of)
Example values: -

ARE13 Subject Type
This class allows to indicate which is the subject of a document.
URI: https://purl.org/episa/archonto/ARE13
Superclass: E55 Type
Subclasses: -
Related properties: - P2 has type
Example values: - Education - Science - Law - Management

ARE14 Place Type
This class allows to indicate which type of place is described, such as a country, municipality or parish.
URI: https://purl.org/episa/archonto/ARE14
Superclass: E55 Type
Subclasses: -
Related properties: -
Example values: - Ocean - Archipelago - Mountain range - Country - District

ARE15 Acquisition Type
This class allows to indicate the type of acquisition of a document, such as purchase, transfer, donation, etc.
URI: https://purl.org/episa/archonto/ARE15
Superclass: E55 Type
Subclasses: -
Related properties: - P2 has type
Example values: - Purchase - Giving - Donation - Deposit - Swap - Legacy - Reintegration - Transfer

ARE16 Event Type
This class allows to indicate which type of event is present in a document.
URI: https://purl.org/episa/archonto/ARE16
Superclass: E55 Type
Subclasses: -
Related properties: - P2 has type
Example values: - Evaluation - Expertise - Financial management

Properties

• ARP8 upper level
• ARP9 lower level
• ARP12 has level of description

ARP8 upper level
This property relates a level of description with the upper levels where it may be aggregated (aggregate).
URI: https://purl.org/episa/archonto/ARP8
Domain: ARE1 Level of Description
Range: ARE1 Level of Description
Inverse: ARP9 lower level
Example values: - The level of description Item (ARE1) has upper level Fonds (ARE1).

ARP9 lower level
This property relates a level of description with the lower levels where it may be aggregated (aggregate).
URI: https://purl.org/episa/archonto/ARP9
Domain: ARE1 Level of Description
Range: ARE1 Level of Description
Inverse: ARP8 upper level
Example values: - The level of description Fonds (ARE1) has lower level Item (ARE1).

ARP12 has level of description
This property relates a given document to its level of description (E22 Human-Made Object).
URI: https://purl.org/episa/archonto/ARP12
Domain: E31 Document
Range: ARE1 Level of Description
Inverse: -
Example values: - The document (E31) has level of description Fonds (ARE1). (fictitious)