Natural language interfaces are a well-known approach to grant non-experts access to semantic web technologies. A number of such systems use simple templates to achieve that for English and more elaborate solutions for other languages. They keep being designed from scratch in an ad hoc manner, since there is no shared conceptualisation of simple templates and there is no model that is formalised using a Semantic Web language to apply the techniques to itself. ToCT is a general-purpose solution to this problem. It is a novel conceptual model formalised as a task ontology in OWL, of templates. It can be used with an accompanying text generation algorithm to produce well-formed text.
The conceptual model for the task ontology for template specifications is as follows:
This was subsequently formalised into OWL as a task ontology. This ontology was used in two evaluation: one for ontology verbalisation in the form of validation quesions in isiZulu (Tbox only) and one for data-to-text generation of weather forcast messages in isiXhosa.
- Input: SubClassOf(http://www.semanticweb.org/mariakeet/ontologies/2016/10/untitled-ontology-315#ihebhu http://www.semanticweb.org/mariakeet/ontologies/2016/10/untitled-ontology-315#umuthi)
- Chosen template: OWLSIZ/Templates/template1.ttl (i.e., Ingabe [subjC]onke [C1] [subjC][COP][C2]?)
- Output: Ingabe lonke ihebhu lingumuthi?
The chosen template has five fragments. See the following snippet:
<templ1> a toct:Template
; toct:supportsLanguage <translZu>
; co:firstItem <ngabe>
; co:lastItem <qmark>
; co:item <onke>, <c1>, <c2> .
As can be seen from the snippet above, the template's first fragment is a unimorphic word <ngabe> and it is followed by the polymorphic word <onke>. Drawing special attention to a dependency between the various fragments, consider the following snippet:
<onke> a toct:PolymorphicWord
; toct:reliesOn <c1>
; co:firstItem <bo>
; co:lastItem <onkeRoot>
; co:nextItem <c1> .
In the above snippet, it is specified, via toct:reliesOn, that the first word is dependent on the noun inserted into the first slot (i.e., <c1>). Currently, the various templates are created manually, however, there is potential to make use of software to make the process easier and faster.
- Zola Mahlaza
- Maria Keet
CC BY 4.0 (https://creativecommons.org/licenses/by/4.0/)
Mahlaza, Z., Keet, C.M. ToCT: A task ontology to manage complex templates. FOIS'21 Ontology Showcase, 13-16 September 2021, Bolzano, Italy. Sanfilippo, E.M. et al. (Eds.). CEUR-WS vol. 2969. 9p. http://ceur-ws.org/Vol-2969/paper40-FoisShowCase.pdf
This work was financially supported by Hasso Plattner Institute for Digital Engineering through the HPI Research School at UCT and the National Research Foundation (NRF) of South Africa (Grant Number 120852).