Realization of tree adjoining grammars with unification

The syntactic generator of the WIP system is based on the representation formalism "Tree Adjoining Grammars" (TAGs). We have extended the formalism by associating elementary rules of the grammar (trees) with feature structures, leading to "Tree Adjoining Grammars with Unification" (UTAGs). The extended formalism facilitates a compact and adequate representation of complex syntactic features. The contradiction between the monotonic operation of unification and the combination operation for trees - adjunction - that is nonmonotonic in a way can be solved by several approaches to realization. Two of them are presented in this work and compared with respect to the restrictions that are given by the system, i.e., the adequacy of the realization for incremental and parallel generation. It can be shown that UTAGs are subsumed by FTAGs (Feature Structure based TAGs) that have been defined by Vijay-Shanker and Joshi. That is why the results for realization can be applied to both UTAGs and a restricted version of FTAGs

Incremental syntactic generation of natural language with tree adjoining grammars

This document combines the basic ideas of my master´s thesis - which has been developped within the WIP project - with new results from my work as a member of WIP, as far as they concern the integration and further development of the implemented system. ISGT (in German \u27Inkrementeller Syntaktischer Generierer natürlicher Sprache mit TAGs´) is a syntactic component for a text generation system and is based on Tree Adjoining Grammars. It is lexically guided and consists of two levels of syntactic processing: A component that computes the hierarchical structure of the sentence under construction (hierarchical level) and a component that computes the word position and utters the sentence (positional level). The central aim of this work has been to design a syntactic generator that computes sentences in an incremental fashion. The realization of the incremental syntactic generator has been supported by a distributed parallel model that is used to speed up the computation of single parts of the sentence

Incremental syntax generation with tree adjoining grammars

With the increasing capacity of AI systems the design of human--computer interfaces has become a favorite research topic in AI. In this paper we focus on aspects of the output of a computer. The architecture of a sentence generation component -- embedded in the WIP system -- is described. The main emphasis is laid on the motivation for the incremental style of processing and the encoding of adequate linguistic units as rules of a Lexicalized Tree Adjoining Grammar with Unification

Incremental generation for real-time applications

The acceptance of natural language generation systems strongly depends on their capability to facilitate the exchange of information with human users. Current generation systems consider the influence of situational factors on the content and the form of the resulting utterances. However, the need to time their processing flexibly is usually neglected although temporal factors play a central part when directly addressing a human communication partner. A short response time of a system is crucial for its effective use. Furthermore, some applications - e.g., the simultaneous description of ongoing events - even necessitate the interleaving of input consumption and output production, i.e. the use of an incremental processing mode. We claim that incremental processing is a central design principle for developing flexible and efficient generators for speech output. We discuss the advantages of parallel processing for incremental generation and several aspects of control of the generator. An extension of Tree Adjoining Grammar is introduced as an adequate representation formalism for incremental syntactic generation. We present the system VM-GEN - an incremental and parallel syntactic generator based on Tree Adjoining Grammars. It offers flexible input and output interfaces that are adaptable to the requirements of the surrounding system by coping with varying sizes of input and output increments. The system's ability to produce fluent speech is a step towards approximating human language performance

PPP-Persona : ein objektorientierter Multimedia-Präsentationsagent

In zukünftigen Benutzerschnittstellen werden zunehmend animierte Präsentationsagenten eingesetzt. Der am DFKI entwickelte Präsentationsagent PPP-Persona dient dazu, den Benutzer durch eine Hypermedia-Präsentation zu führen. Dank seiner objektorientierten Konzeption ist er jedoch auch für eine Vielzahl weiterer Anwendungen einsetzbar, wie beispielsweise Online-Hilfesysteme, Home-Shopping und Tele-Banking. Dem Paradigma der Client/Server-Architektur folgend, empfängt der PPP-Persona-Server Präsentationsaufgaben von einem Anwendungsprogramm, die dieser dann selbständig ausführt. Zur visuellen Realisierung des Präsentationsagenten kann sowohl auf Cartoon-Zeichungen als auch auf Videobildmaterial zurückgegriffen werden. Um die Präsentation lebendiger zu gestalten, kann PPP-Persona selbständig Animationssequenzen initiieren

DFKI Workshop on Natural Language Generation

On the Saarbrücken campus sites as well as at DFKI, many research activities are pursued in the field of Natural Language Generation (NLG). We felt that too little is known about the total of these activities and decided to organize a workshop in order to share ideas and promote the results. This DFKI workshop brought together local researchers working on NLG. Several papers are co-authored by international researchers. Although not all NLG activities are covered in the present document, the papers reviewed for this workshop clearly demonstrate that Saarbrücken counts among the important NLG sites in the world

DFKI Workshop on Natural Language Generation

On the Saarbrücken campus sites as well as at DFKI, many research activities are pursued in the field of Natural Language Generation (NLG). We felt that too little is known about the total of these activities and decided to organize a workshop in order to share ideas and promote the results. This DFKI workshop brought together local researchers working on NLG. Several papers are co-authored by international researchers. Although not all NLG activities are covered in the present document, the papers reviewed for this workshop clearly demonstrate that Saarbrücken counts among the important NLG sites in the world