tailieunhanh - Báo cáo khoa học: "NOMINALIZATIONS IN PUNDIT"

This paper describes the t r e a t m e n t of nominalizations in the P U N D I T text processing system. A single semantic definition is used for both nominalizations and the verbs to which they are related, with the same semantic roles, decompositions, and selectional restrictions on the semantic roles. However, because syntactically nominalizations are noun phrases, the processing which produces the semantic representation is different in several respects from t h a t used for clauses. | NOMINALIZATIONS IN PUNDIT Deborah A. Dahl Martha s. Palmer Rebecca J. Passonneau Paoli Research Center UNISYS Defense Systems1 Defense Systems UNISYS Box 517 Paoli PA 19301 USA ABSTRACT This paper describes the treatment of nomi-nalizations in the PUNDIT text processing system. A single semantic definition is used for both nomi-nalizations and the verbs to which they are related with the same semantic roles decompositions and selectional restrictions on the semantic roles. However because syntactically nominaliza-tions are noun phrases the processing which produces the semantic representation is different in several respects from that used for clauses. 1 The rules relating the syntactic positions of the constituents to the roles that they can fill are different. 2 The fact that nominalizations are untensed while clauses normally are tensed means that an alternative treatment of time is required for nominalizations. 3 Because none of the arguments of a nominalization is syntactically obligatory some differences in the control of the filling of roles are requừed in particular roles can be filled as part of reference resolution for the nomi-nalization. The differences in processing are captured by allowing the semantic interpreter to operate in two different modes one for clauses and one for nominalizations. Because many nomi-nalizations are noun-noun compounds this approach also addresses this problem by suggesting a way of dealing with one relatively tractable subset of noun-noun compounds. formerly SDC A Burroughs Company. 1. Introduction In this paper we will discuss the analysis of nominalizations in the PUNDIT text processing Syntactically nominallzations are noun phrases as in examples l - 7 . 1 An inspection of lube oil filter revealed metal particles. 2 Loes of lube oil pressure occurred during operation. 3 SAC received high usage. 4 Investigation revealed adequate lube oil. 5 Request replacement of SAC. 6 Erosion of impellor blade tip is .