%A NIE Deng-guo, YU Quan, ZHANG Wei and SHEN Yu-ming %T Conservative Extensions in Description Logic εVL %0 Journal Article %D 2016 %J Computer Science %R 10.11896/j.issn.1002-137X.2016.6A.019 %P 83-86 %V 43 %N Z6 %U {https://www.jsjkx.com/CN/abstract/article_15383.shtml} %8 2018-12-01 %X In fact ontology is definitely the structured knowledge base in description logic.As we know,knowledge is not always the same,so it needs to be extended as long as new improvement appears in this field.It is concerned that whether it is consistent with the primitive one after extension.The conservative extension of εVL system was analyzed based on Lutzs’ work.Firstly the εVL canonical model was constructed and the inclusion inference was reduced to the simulations between two εVL canonical model.The complexity was pointed out to be polynomial based on that the canonical models’ largest simulation is polynomial.After that the εVL conservative extension algorithm was presented and its complexity was proved to be exponential.