The dual-level index model of text retrieval system based on concept

The technology of concept extending has been researched to deal with the vocabulary mismatch problem for the text retrieval systems. It can not be avoided that the concept extending leads to more time cost of the retrieval systems. To aim at solving the problem, this paper puts forward a novel retrieval system, which is based on a dual-level index model. The dual-level index model introduces the index mechanism into the concept extending, to allow quick extending. Moreover, the model combines the memory buffering mechanism with the index of concept extending, to speed up the extending process. In order to apply the dual-level index model, a retrieval method is given for the retrieval system. The experimental results show that the method achieves a better runtime performance.