Design knowledge retrieval technology based on domain ontology for complex products

To solve the problem that knowledge couldn't be discovered and reused easily in product data management system, a design knowledge retrieval technology based on domain ontology was proposed. A "domain ontology-index knowledge-data resource" three-layer mapping structure was put forward to represent design knowledge. The design knowledge system was formed consisting of domain ontology as semantic model and index knowledge as searching index. A new knowledge retrieval method based on semantics was put forward. Design problem was analyzed based on semantics and transformed into ontology concepts. To match knowledge which satisfied designer's search intentions, a text similarity computation based on vector space model which introduced relation weight to those ontology concepts and domain weight to words of knowledge text was proposed. Finally, an example of cruise missile's overall design was provided to reveal the feasibility of retrieval technology.