Real-time semantic annotation device and the method of creating ontology documents on-the-fly from natural language strings entered by user

PURPOSE: A real-time semantic annotation device and a method of creating ontology documents on-the-fly from natural language strings entered by a user are provided to accurately perform annotation by inputting a substitute word instead a difficult word. CONSTITUTION: A natural language string input unit receives a natural language character string, and a string pattern triple-mapping table stores a ripple pair corresponding to a natural language string pattern. A triple extracting unit converts the natural language string into a triple format, and a substitute word recommendation unit recommends the substitute words to a user. A machine readable document generator generates a machine readable document from the triple through a meaningful readable knowledge structure.