6. Discussion
Jean Vincent Fonou Dombeu and Magda Huisman
This study reviews and discusses technologies for building semantic‐based e‐Government applications including ontology, Semantic Web ontology languages and platforms, semantic data storage and query languages, and Semantic Web Services. As shown in Figure 2, ontology is the main component of any Semantic Web application. Due to space constraints, this study did not expand on the methodology employed to build the domain ontology used( See Figure 1). Interested readers may refer to Fonou‐Dombeu and Huisman( 2010). Furthermore, the semi‐formal representation of the domain ontology in Figure 1 that provides the implementable version of the ontology in terms of classes, class hierarchy, properties / slots, restrictions, etc. was represented in description logic in this study; this could also be done in UML as in Fonou‐Dombeu and Huisman( 2011).
Moreover, the recent years have witnessed the widespread adoption of Semantic Web technologies in various domains; this has enabled Semantic Web developers to argue that ontology building is a time consuming, labour intensive and expensive task in semantic web development. To address this challenge, studies( Maedche et al. 2003; Ding et al. 2007) have proposed the reuse of existing domain ontologies when building new ones. In fact, ontology reuse may( 1) reduce the effort required to formalized new ontologies de novo,( 2) increase the quality of the resulting ontologies because the reused ontologies have already been tested,( 3) simplify the mapping between ontologies built using shared components of existing ontologies, and( 4) improve the efficiency of ontology maintenance( Ding et al. 2007). To support e‐Government domain ontologies reuse, Fonou‐Dombeu and Huisman( 2012) investigated and discussed existing e‐Government domain ontologies on the Semantic Web.
The study generates stores and queries the RDF representation of the e‐Government domain ontology in Figure 1 with Jena API. A similar process to that in Figure 2 could be used to generate and save the OWL version of the domain ontology with Protégé as in Fonou‐Dombeu and Huisman( 2011).
The building, implementation, storage and query of domain ontology as it is done in this study constitute the static aspect of any Semantic Web application. The dynamic part of Semantic Web technologies based on Semantic Web services and reasoning was not covered in this study and will be dealt with in our future research.
7. Conclusion
Semantic Web technologies including ontologies, Semantic Web ontology languages and platforms, semantic data storage and query languages, and Semantic Web Services were reviewed and discussed. Thereafter, a domain ontology describing a government service domain is implemented, stored and queried to illustrate the Semantic Web development process. More importantly, the study provides clarification on the engineering process of Semantic Web applications. This may assist e‐Government developers, particularly those of developing countries where there is little or no practice of Semantic Web technologies in e‐Government processes, to practice these technologies in their projects and build intelligent and interoperable e‐ Government systems.
However, practicing Semantic Web technologies required expertise in various areas such as ontology and knowledge engineering, programming languages, database, machine learning, etc. This required experienced and qualified people to carry out Semantic Web development in e‐Government. This challenge could be dealt with in the long‐term by( 1) introducing courses on Semantic Web technologies in e‐Government studies in information technology, computer science, and software engineering programmes at academic institutions,( 2) developing partnerships between academic institutions, industry and government for the efficient utilization of the trained graduates and( 3) encouraging collaboration between countries with successful semantic‐based e‐Government implementation and those with Semantic Web skill shortages through exchange programmes and workshops.
References
Bailey, J., Bry, F., Furche, T. and Schaffert, S.( 2009) Semantic Web Query Languages, Encyclopedia of Database Systems 2009, pp. 2583‐2586.
Barthes, J. P. and Moulin, C.( 2005) Impact of e‐Government on Territorial Government Services, Deliverable No. 1.4, Available: http:// www. terregov. eupm. net,( Last Access 06 / 12 / 2011)
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