The **_Discourse Elements Ontology (DEO)_** is an ontology written in OWL 2 DL that provides a structured vocabulary for rhetorical elements within documents (e.g. Introduction, Discussion, Acknowledgements), enabling these to be described in RDF.
The main class of this ontology is `deo:DiscourseElement`, which describes all those elements of a document that carry out a rhetorical function.
All the remaining rhetorical behaviours are modelled as subclasses of this class.
Some of the DEO entities are aligned with some of the rhetorical blocks from the [SALT Rhetorical Ontology](http://lov.okfn.org/dataset/lov/vocabs/sro) and the [Ontology of Rhetorical Blocks (ORB)](http://www.w3.org/2001/sw/hcls/notes/orb/), and extends them by introducing additional classes, including the following:
* `deo:Reference`, which specifies a connection either to a specific part of the document or to another publication.
In written text, numbered superscripts standing for footnotes, items in a table of contents, and items describing entities in a reference section, can be modelled as individuals of this class;
* `deo:BibliographicReference`, a subclass of the `deo:Reference` that describes references to other publications, such as journal articles, books, book chapters or websites; such references are often contained in a footnote or a bibliographic reference list;
* `deo:Caption`, that defines the text accompanying another item (e.g., the legend describing a picture);
* `deo:Introduction`, the initial description that states the purpose and goals of the subsequent text;
* `deo:Materials`, that documents the specific materials used in the described work;
* `deo:Methods`, that documents the methods used in the work (may be combined with a description of the materials used);
* `deo:Results`, that describes a report of the specific findings of an investigation;
* `deo:RelatedWork`, that describes a critical review of current knowledge by specific reference to other relevant works, both in terms of substantive findings and theoretical and methodological contributions within a domain of study;
* `deo:FutureWork`, a proposal for new investigations to be undertaken in order to continue and advance the work described in the publication.
Note that it is still possible to apply two different rhetorical characterisations to the same block of text.
For instance, in journal articles it is common to have a section entitled "Materials and Methods", which can be characterised rhetorically by using both the classes `deo:Methods` and `deo:Materials`.
DEO is imported in [DoCO](http://purl.org/spar/doco), which is an OWL 2 DL ontology that provides a general-purpose structured vocabulary of document elements.
## Examples of use
In the following subsections, we introduce some examples to showcase how to use DEO.
The prefixes that are used in all the examples provided below are defined as follows:
@prefix deo: <http://purl.org/spar/deo/> .
@prefix doco: <http://purl.org/spar/doco/> .
@prefix c4o: <http://purl.org/spar/c4o/> .
@prefix cito: <http://purl.org/spar/cito/> .
@prefix schema: <http://schema.org/> .
@prefix dcterms: <http://purl.org/dc/terms/> .
@prefix xsd: <http://www.w3.org/2001/XMLSchema#> .
### Tagging paper blocks with rhetoric entities
DEO can be used in order to characterise the major rhetorical elements of a research article, such as the introduction part, the evaluation section, the conclusions and so on.
<#paper>
dcterms:title "Semantic Structuring of Scholarly Articles in HTML5" ;
dcterms:hasPart
<#sec_abstract> ,
<#sec_intro> ,
<#sec_methods> ,
<#sec_eval> ,
<#sec_concl> .
<#sec_abstract> a doco:Section, deo:Abstract ;
dcterms:title "Abstract" ;
c4o:hasContent "This paper introduces an end-to-end framework for embedding fine-grained discourse elements..."@en .
<#sec_intro> a doco:Section, deo:Introduction ;
dcterms:title "1. Introduction" ;
dcterms:hasPart <#p_problem_statement> .
<#p_problem_statement> a doco:Paragraph, deo:ProblemStatement ;
c4o:hasContent "Current semantic publishing pipelines often fail to preserve structural dependencies between discourse units."@en .
<#sec_methods> a doco:Section, deo:Methods ;
dcterms:title "2. System Architecture & Methods" ;
dcterms:hasPart <#p_algorithm> , <#sec_materials> .
<#p_algorithm> a doco:Paragraph, deo:Model ;
c4o:hasContent "We formulate discourse mapping as an acyclic graph traversal over the DOM tree." ;
cito:extends <http://dx.doi.org/10.1007/978-3-540-89704-0_17> .
<#sec_materials> a doco:Section, deo:Materials ;
dcterms:title "2.1 Benchmark Dataset" ;
c4o:hasContent "Evaluation uses a corpus of 1,200 open-access biomedical and computer science preprints." .
<#sec_eval> a doco:Section, deo:Evaluation, deo:Results ;
dcterms:title "3. Experimental Results" ;
c4o:hasContent "The proposed extractor achieves an F1-score of 94.2% on heterogeneous layouts." .
<#sec_concl> a doco:Section, deo:Conclusion ;
dcterms:title "4. Conclusion & Outlook" ;
dcterms:hasPart <#bloc_future_work> .
<#bloc_future_work> a doco:Paragraph, deo:FutureWork ;
c4o:hasContent "Future research will integrate large multimodal models for direct visual-layout grounding." .
## Competency Questions
DEO can be used for answering several questions related to rethorical elements used in documents.
In the following subsections, some of them are introduced together with their respective SPARQL queries.
The prefixes that are used in all the SPARQL queries provided below are defined as follows:
PREFIX deo: <http://purl.org/spar/deo/>
PREFIX cito: <http://purl.org/spar/cito/>
PREFIX c4o: <http://purl.org/spar/c4o/>
PREFIX doco: <http://purl.org/spar/doco/>
PREFIX dcterms: <http://purl.org/dc/terms/>
### CQ1
What are the structural sections of a paper and their specific discourse roles?
SELECT ?paper ?section ?title ?role
WHERE {
?paper dcterms:hasPart ?section .
?section a doco:Section, ?role .
FILTER(?role != doco:Section)
OPTIONAL { ?section dcterms:title ?title . }
}
### CQ2
Which internal discourse models or components extend external works?
SELECT ?element ?citedWork ?content
WHERE {
?element a deo:Model ;
cito:extends ?citedWork .
OPTIONAL { ?element c4o:hasContent ?content . }
}
### CQ3
What is the future work outlined in the conclusion of a document?
SELECT ?conclusionSection ?futureWorkElement ?futureWorkContent
WHERE {
?conclusionSection a deo:Conclusion ;
dcterms:hasPart ?futureWorkElement .
?futureWorkElement a deo:FutureWork ;
c4o:hasContent ?futureWorkContent .
}