Secondly , based on reference model and data - flow model of traditional cad systems , a cooperative information model of collaborative cad systems for the aircraft cooperative design system was put forward . the information model includes various correlative data and knowledge for the plan , development , implement and realization of the aircraft project . according to the demands of the information model we setup distributed database environment for the cooperative system 通過(guò)分析傳統(tǒng)cad系統(tǒng)的參考模型和數(shù)據(jù)流模型,結(jié)合協(xié)同開(kāi)發(fā)環(huán)境的需要建立了協(xié)同cad設(shè)計(jì)系統(tǒng)的信息模型,并為從項(xiàng)目計(jì)劃、項(xiàng)目開(kāi)發(fā)、項(xiàng)目實(shí)施到完成的產(chǎn)品開(kāi)發(fā)全過(guò)程中涉及的各種信息和知識(shí),如人員信息、項(xiàng)目信息、通訊信息、設(shè)計(jì)信息等建立信息模型。