The number of learning situations that can be carried out in a VLE (Virtual Learning Environment) can be improved by the integration of third-party external tools. Before the integration takes place, it is compulsory to retrieve some information, both to select the most appropriate tool to support an speci c situation and to be able to integrate it in the VLE. Current tool registries have some drawbacks that make the data retrieval di cult for the educators; among these drawbacks, the most important one is that search engines are not able to automatically import information from external datasets. To overcome this limitation, this paper introduces an ongoing doctorate research that proposes the creation of a search engine based on the Linked-Data principles.
designed to retrieve text documents and not data about software tools; these
documents may contain a text description about software tools, but data must
be extracted out of them by a human. In order to facilitate the software tool
data retrieval, some other search engines, such as Google Gadgets3 or Yahoo!
Widgets4, give support for searching tools, providing data about thousands of
tools. Moreover, they are commonly used by non-expert users. However, these
kind of search engines are not specialized in educational domain, so they do
not provide educational information related to the tools; in addition they are
keyword-based search systems, which are prone to obtain irrelevant results [8,
Pag. 91]. These drawbacks are overcome by OntoolSearch5, an educational tool
search engine based on semantic technologies that use the Ontoolcole [
Another important drawback that is common to all the aforementioned search systems is that they are not able to automatically import information from thirdparty external repositories. These search systems can only take information from their own internal registry, which behaves as a independent data silo. Thus, each search system is only able to provide the information that has been explicitly described in its internal registry, even if there is more relevant information in another dataset freely accessible through the Web. Moreover, a software tool may be described in a search system internal registry but it may have been updated in another external data source, so a teacher that uses this search system will get out-of-date information. 2
The most important problem that this doctorate research work is trying to solve
is how to create an educational tool search engine able to automatically collect
information from third-party external data repositories. Obviously, the problem
of integrating external data does not only a ect to the educational domain; it
is a very important problem to solve related to the information retrievement
and data management. The Linked Data [
Linked Data is a methodology for publishing data in the Semantic Web [
In the Web of Data there are several interlinked data repositories with information from multiple domains. Even if none of them provide speci c information about educational tools, there are some data repositories where useful information of software tools is registered. One of these datasets is DBpedia7, where up-to-date structured information extracted from Wikipedia is freely available. A key step to solve the proposed research question is to design a search system able to extract structured data from di erent sources from the Web of Data, such as Dbpedia, and automatically relate the data to the system internal vocabulary. Note that the data extraction from each dataset will not be ad-hoc implemented because, as di erent data sources are linked, a single software agent can extract information from several datasets.
However, there is no data registry in the Web of Data that describes software tools contemplating their educational capabilities, nor there is any that give details about how to integrate them in a VLE. So that, the support of searching tools using educational abstractions will be limited. In order to solve this problem a search engine is proposed; this search engine will have a collection of adaptors that will allow to automatically extract data from di erent sources. Moreover, in order to complete the description of software tools , teachers can publish their educational capabilities and technical users can give details of how to integrate them in a learning environment. This way, a new interlinked dataset will be created, containing information with a speci c purpose and reusing information from multiple previously available data repositories. 3
In order to design, develop and evaluate an educational tool search system, the
doctorate research is being iteratively performed according to the methodology
in engineering [
The whole picture of the research proposal is represented in Figure 1. Doctorate research has been working on some of the partial objectives described in Section 2. Speci cally, previous work has focussed on the detection of the information requirements for the tool integration in VLEs and in the design of the search engine architecture.
In order to detect the information that should be provided by the system,
some real examples were studied where a tool is published by a tool provider,
found and selected by a teacher and later on integrated in a VLE. Furthermore,
an analysis of the literature was carried out. Out of this review the tool
information requirements were established: the description of the tool should
contemplate both functional, technological and administrative parameters of the tool.
Once the information requirements were analyzed, an ontology was design in
order to de ne a vocabulary that can be used by the search system to describe the
learning tools. This ontology reuses other conceptualizations that can be found
in the literature; for example, Ontoolcole [
As far as the search engine design concerns, the proposed architecture, which
is based on papers such as [
The present paper shows an ongoing doctorate research work. A research question was detected, which consists on the design of an educational tool search engine able to automatically collect information from external data repositories. The proposed approach to solve this problem is based on the Linked Data principles because it is a recent trend that allows software agents to automatically retrieve information from the Web of Data.
This approach overcomes the detected problems in current educational tool search systems, such as OntoolSearch: rstly, it is possible to nd educational tools that were not speci cally described in the system's data source; secondly, data maintenance will be facilitated, as the system is able to automatically import up-to-date information; nally, the publication of educational tool information will be easier, since it will be possible to reuse the data retrieved from external registries, so it will only be necessary to registry the tools educational aspects. In addition, all the information created by the system will be published and will be freely available on the Web, so it could be reused by other people for some other educational applications.
Future work will focus on the implementation of the search system described in Section 4, taking into account the proposed architecture and the designed ontology. In addition, the integration of the search system in at least a VLE will be an interesting task to be carried out.