Research On The Organization Of Educational Resources And Semantic Retrieval Based Ontology

In China, digital information has grown at a speed of more than 90 billion GB each year, the number has reached 9.1% of the total global information. It brings daunting challenges as well as opportunities to the education industry. E-Learning(online learning) is a new way of learning, it can break the limitation of time and space. It is a learner centered, individualized, autonomous teaching mode. Because of this, the organization, retrieval, management of massive learning resources is a research hotspot. At present, education resources in the network does not have a unified standard, the sharing of uneven resources is low, there is no semantic relationship between various resources. Learners cannot sharing a wide range of network teaching resources. In addition, in the current circumstances, the network education resources is growing at a million level, while the existing search engines are based on keywords, without considering the semantics of the correlation between words and words, can’t provide a more accurate, efficient search engine for the users. These phenomena caused the waste of the network education resources.The general search engine only focus on the query itself, rather than inferring the nature, speculation the true intension. Semantic retrieval did it, It can carry out a dozen search and return the search result to the users which meets the users’ demand. According to the need of network learning and applications, semantic web education resource search can be used in various platform. All kinds of information resources in network marked by semantic, user query semantic processing through the semantic annotation, that makes it has the semantic logical relation. Therefore, in the network environment, it can be broad and effective for semantic reasoning, which is more exact and comprehensive to achieve the user’s retrieval.This paper first introduces the education resource and the current situation of information retrieval, then proposed the problems and introduces the ontology semantic retrieval, explains the related theories of ontology. Including the basic knowledge of ontology, the classification of the ontology, ontology modeling languages and methods, writing tools. Use seven steps builds ontology, including use the knowledge Unit to build the domain ontology and use the CELTS metadata standard to construct education ontology. In the environment of semantic search, query expansion method is proposed firstly, then processing the query, including word segmentation, word extraction to pause, retrieval words, mapping the concepts, by constructing the concept of search tree to infer the users’ search intent, set dynamic threshold to expand the query to enrich the users’ information retrieval. Finally, develop a prototype retrieval of educational resources based on ontology and use test method to verify its effectiveness. The experimental data are analyzed and compared to the results, In the retrieval of educational resources, calculate the similarity between words and using the vector space model to initial the results of the resource retrieval and other related resources are retrieved through reasoning. Finally, the retrieval result has been sent back to user. The retrieval method proposed in this paper that the recall and precision compared with the traditional method are improved.