Metadata architecture for digital library integration

Although the rapid development in digital library has accelerated the use of metadata, conventional metadata is insufficient to be integrated across heterogeneous digital libraries. In this paper, three-layer metadata architecture is proposed to integrate digital libraries by activating the metadata structure. Metadata extraction layer obtains data automatically from distributed digital libraries. Semantic query layer searches transparently to solve semantic heterogeneity. Data clustering layer integrates search result with each sub-structure to improve accuracy. Adapting the three-layer architecture is beneficial for semantic search and alleviates the administrative effort to construct digital library services.