Fig. 4From: Comprehensive structured knowledge base system construction with natural language presentationAn example of a class ‘water’ defined by the proposed ontology. The words in the grey circles are concepts and the root is denoted by the orange circle. The different coloured dashed arrows indicate the relationship between concepts according to the features of the concept ‘water’ i.e. <water, no, taste\(> <\)water, no, colour> while the solid arrows indicate the subclassesBack to article page