An Abstraction Method Using a Semantic Engine Based on Language Information Structure

This paperdescribes the framework for a new abstraction method that utilizes event-tmits written in sentences. Event-units are expressed in Language Information Structnrc (LIS) form and the projection of LIS from a sentence is f)cffonned by a semantic engine. ABEX (ABstraction EXtraction system) utilizes the LIS outpttt of the s e m a n t i c e n g i n e . A B I ' ; X can e x t r a c t e v e n t s f r o m sentences and classify them. Since ABEX and t h e L I S f o r m nsc o n l y l i m i t e d k n o w l e d g e , the s y s t e m n e e d no t c o n s t r u c t o r n l a in t a in a l a rge a m o u n t o f k n o w l e d g e . 1 I n t r o d u c t i o n Automatic abstraction, a lnajor natural lauguagc ]n'uecssing application, is difficult to achieve. Luhn[5] developed a very simple extraction method that searches for the keywords ill each sentence. This type nf abstraction is easy to accomplish, but its quality is poor. Other abstraction methods[6, 31 utilize natural language unde r s~d ing (NLU). However NLU is still in the development stage. For achieving good practical performance, it is necessary to treat the thformation expressed in a tlocument uniformly so that it can be analyzed with only a small fixed amount of knowledge. We propose tile L.IS form which allows inlormatinn about events tO Lvd un i lo l ln ly treated, t;urt[lcl~nore, the semantE engine only uses abstract words, this reduces thc size of the knowledge. So the semuntic engine projects a sentence to a LIS form within a lmdted anloant of knowledge. In abstraction, classification is the first step. Classification is performed using unilorln approach, the LIS lkmn. LIS event representation ullow us to select and classify sentences, 2 A s e m a n t i c e n g i n e 2.1 What is the l,anguage Information Strncture(LIS) form? The LIS form expresses the inlormation structure that pernlits commnnication between individuals. If two ino dividuals communicate about one that happened (will happen) m the real world, the core inlormation is the event. Sometm~es a spe,aker will atulche an attitude to the event. So information al~ml real world is expressed by the event and the attitude of tile speaker.