Transforming English Interfaces to Other Natural Languages: An Experiment With Portuguese

TRANSFORMING ENGLISH INTERFACES TO OTHER NATURAL LANGUAGES: AN EXPERIMENT WITH PORTUGUESE GABRIEL PEREIRA LOPES (1) Departamento de Matem~tica • Instituto Superior de Agronomia Tapada da Ajuda - 1399 Lisboa Codex, Portugal ABSTRACT Nowadays it is common the construction of English understanding systems (interfaces) that soo- ner or later one has to re-use, adapting and conve~ ting them to other natural languages. This is not an easy task and in many cases the arisen problems are quite complex. In this paper an experiment that was accomplished for Portuguese language is reported and some conclusions are explicitely stated. A know ledge information processing system, known as SSIPA, with natural language comprehension capabilities that interacts with users in Portuguese through a Portuguese interface, LUSO, was built. Logic was u- sed as a mental aid and as a practical tool. I. INTRODUCTION The CHAT-80 program for English (Warren & Pereira, 1981; Pereira, 1983) was transformed and a dapted to Portuguese. Logic Programming as a mental aid, and Prolog (Coelho, 1983; Clocksin & Melish , 1981) and Extraposition Grammars (Pereira, 1983) as practical tools, were adopted to implement a natu- ral language interface for Portuguese. The interfa- ce here reported, called LUSO, was then coupled to a knowledge base for geography, an extension of the CHAT-80 knowledge base. In an ulterior experiment , LUSO dictionary was augmented with new vocabulary and LUSO was coupled to other modules that conside- rably augmented the expertise capabilities of SSIPA (Sistema Simulador de um Interlocutor Portugu~s Au- tom~tico (2)). SSIPA is a complex knowledge information processing system with natural language comprehension and syn- thesis capabilitites that interacts with users in Portuguese due to the linguistic knowledge that is logically organized and codified in the above men- tioned SSIPA's interface ca]led LUSO.After the first step of its development, SSIPA was able to answer (1) Present Adress: Centro de Inform~tica, Laborat5 rio Nacional de Engenharia Civil, lOl, Av. do Bra= sil, 1799 Lisboa Codex, Portugal (2) Simulating System of a Portuguese Automatic In- terlocutor. questions about geography and could agree or disa- gree with the opinions stated by the users about its geographical knowledge. After the second step of its development SSIPA became more powerful and intelligent because it could also perform actions that traditionally were attributes of computer mo- nitors (Lopes & Viccari, 1984).As a matter of fact, SSIPA can create and delete files, fill them, change their names, list and change their, contents; SSIPA receives, keeps and send messaqes answers questions not only about geography but also about the knowledge SSIPA represents; it a - grees or disagrees with the opinions stated byusers about the Knowledg~ context behind dialogues, reacts when users try to cheat it but, as a rule, SSIPA behaves as a helpful, deligent and cooperat~ ve interlocutor willing to serve human users, chan ging from one to another topic of conversation and developing intelligent clarification dialogues (Lo pes, 1984). All these features require a very power ful Portuguese language interface whosemain moron~ -syntactic features are pointed …

Content truncated to 500 words