Universities around the world have been taking advantage of open educational resources (OERs) for publishing educational material. The teachers and students can access, the published material for teaching, learning and research through institutional repositories. This article proposes the design, construction and validation of the semantic platform (MIIDAS), considering two case studies of higherlevel educational institutions (civil and military schools). The MIIDAS Platform integrates educational resources in institutional repositories related to the areas of Computing and Electronics engineering through the incorporation of Semantic Web technologies. The descriptions of resources consider metadata of the OAI-PMH protocol and also add educational metadata. The platform uses RDF resource descriptions, ontologies and the SPARQL query language to improve resource retrieval, in addition to proposing guidelines for the management of educational resources. The results of validation of the platform are presented through the development of evaluation instruments, which suggest possible ways to improve the platform. The article provides the basis for developing platforms that help in spreading open educational resources and allow the construction of semantically enrich data sets.