摘要
随着教育信息化进程的大力推进,网络教育资源的建设越来越受到国家和各高校的重视.语义网提供了语义互操作模型,能有效实现网络资源的发现、共享和集成应用.阐述了语义网、语义检索、本体构建、元数据标准等关键技术,分析了本体与元数据的关系,给出了基于元数据的教育资源本体构建方法.设计了基于本体的网络教育资源语义检索系统,该系统由资源入库与语义标注器、本体管理器、检索预处理器、检索重构器、检索引擎共5大部分组成.其中资源入库子系统对教育资源进行预处理、分类存储和管理;语义标注器根据教育资源任务本体构造相应的语义模板并进行语义标注;本体管理器负责完成OWL格式本体的存储、访问和更新;检索预处理器对查询请求进行分词、词性标注和规范化处理后形成查询向量;检索重构器对查询向量中的查询词进行语义扩展后重构出SPARQL查询语句;检索引擎根据SPARQL查询语句响应查询请求,并对检索结果进行排序后返回给用户.实验表明基于本体的语义检索提高了网络教育资源检索的查全率和查准率.
With the promoting of educational informatization process, building network education resources is obtained increasing concern by the state and the university . The semantic web provides semantic interoperation model, it can realize the network resource discovery, sharing and the integrated application effectively. Firstly, the key technologies are summarized such as semantic web, semantic retrieval, ontology building and metadata standards etc. Then, the relationship between ontology and metadata is analyzed, and the building method of educational resources ontology based on metadata is presented. Finally, the semantic retrieval system for network education resources based on ontology is designed. The system consists of total of five major components, which includes resources storage and semantic annotation, ontology manager, retrieval preprocessor, retrieval reconstruction and retrieval engine. Storage Subsystem in which education resources are preprocessed, classified storage and management; Semantic an- notation processes semantic annotation according to relevant semantic templates which are constructed task ontologies of educational resources; Ontology manager in which charge of store, access and update of the OWL format ontology; Retrieval Preprocessor processes word segmentation, part of speech tagging and standardization for forming the query vector~ Retrieval Reconstruction for semantic extension of query words in the semantic query vector to reconstruct SPARQL （Simple Protocol and RDF Query Lan- guage） query; Retrieval engine responses query requirements according to SPARQL and returns search results to the user by sorting, Experiments show that ontology-based semantic retrieval improves search recall and precision for retrieving network educational resources.
出处
《华中师范大学学报（自然科学版）》
CAS
CSCD
北大核心
2011年第4期551-556,581,共7页
Journal of Central China Normal University：Natural Sciences
基金
湖南省教育科学"十一五"规划重点资助课题(XJK08AXJ002)
湖南省科技计划项目(2011FJ3033)
湖南省教育厅优秀青年资助科研项目(11B104)
娄底市科技计划项目
湖南人文科技学院教学改革研究项目(RKJGY1001)
关键词
网络教育资源
语义检索
本体
语义网
network education resources
semantic retrieval
ontology
semantic web
