A situated ontology is a world model used as a computational resource for solving a particular set of problems. It is treated as neither a "natural" entity waiting to be discovered nor a purely theoretical construct. This paper describes how a semantico-pragmatic analyzer, Mikrokosmos, uses knowledge from a situated ontology as well as from language-specific knowledge sources (lexicons and microtheory rules). Also presented are some guidelines for acquiring ontological concepts and an overview of the technology developed in the Mikrokosmos project for large-scale acquisition and maintenance of ontological databases. Tools for acquiring, maintaining, and browsing ontologies can be shared more readily than ontologies themselves. Ontological knowledge bases can be shared as computational resources if such tools provide translators between different representation formats. 1 A Situated Ontology World models (ontologies) in computational applications are artificially constructed entities. ...

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Abstract. Treatment of meaning in NLP is greatly facilitated if semantic analysis and generation systems rely on a language-neutral, independently motivated world mod-el, or ontology. However, the benefits of the ontology are somewhat offset in practice by the difficulty of its acquisition. This is why a number of computational linguists make a conscious choice to bypass ontology in their semantic deliberations. This deci-sion is often justified by questioning the principles underlying ontologies and by chal-lenging the ontology-based semantic enterprise on the grounds of its ostensible irreproducibility. In this paper we briefly illustrate the expressive power of ontological lexical-semantic descriptions used in the Mikrokosmos machine translation project and make a comparison with some of the non-ontological approaches to lexical se-mantics. We argue that these approaches, in reality, rely on ontologies in everything but name. We claim that no underlying principles for ontologies are possible and ex-plain why the charge of irreproducibility is not valid. The central tenet of ontology-based semantics is "grounding " the meanings of lexical units in an independently motivated and interpreted system of symbols, an ontology.

In the field of natural language processing (NLP) there is now a consensus that all NLP systems that seek to represent and manipulate meanings of texts need an ontology, that is a taxonomic classification of concepts in the world to be used as semantic primitives. In our continued efforts to build a multilingual knowledge-based machine translation (KBMT) system using an interlingual meaning representation, we have developed an ontology to facilitate natural language interpretation and generation. The central goal of the Mikrokosmos project is to develop a computer system that produces a comprehensive Text Meaning Representation (TMR) for an input text in any of a set of source languages. Knowledge that supports this process is stored both in language-specific knowledge sources (such as a lexicon) and in an independently motivated, language-neutral ontology of concepts in the world.

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. We present in this paper the methodology developed within the PARADIME (Parameterizable Domain-Adaptive Information and Message Extraction) project for designing an Information Extraction (IE) system easily adaptable to new domains of application. For this we went for a strict separation of the (shallow) linguistic processing modules on the one hand and the domain-modeling modules on the other hand, thus looking for the maximal degree of reusability of common linguistic resources shared by all domains of application. The tools used for the domain-modeling allow a declarative description of the domain under consideration and a simple (abstract) mapping to the output of the Natural Language (NL) analysis, thus requiring only few and very general linguistic knowledge for the adaptation of the IE-system to new applications. We describe a real scale experiment on a fast adaptation cycle of the system to a new domain -- the soccer domain -- and present the first results obtained.

this paper. The terms attribute is tagged with the keyword multilingual which of course means that it is a multilingual attribute.

We describe techniques based on natural language generation which allow a user to author a document in controlled language for multiple natural languages. The author is expected to be an expert in the application domain but not in the controlled language or in more than one of the supported natural languages.

This thesis concerns the use of ontologies in natural language processing. An ontology is a formal model of knowledge of the world, where concepts, properties and relations in the real world are defined in some knowledge representation language. Machine translation is one of the many possible applications of ontologies. In this setting, they are commonly used for representing the semantics of lexical items, which is given by means of mapping words to ontological concepts. Ontologies used for this purpose are typically built for a particular system that handles only a small set of languages and are not easily extensible for new languages. In order to achieve a more generally applicable ontology, the relation between lexical items and ontological concepts needs to be studied carefully. A study of this form is presented in this paper, with the emphasis on trying the following hypothesis; that the mapping of words to the ontology is simplified if the ontology has knowledge of how ontologic...

. Treatment of meaning in NLP is greatly facilitated if semantic analysis and generation systems rely on a language-neutral, independently motivated world model, or ontology. However, the benefits of the ontology are somewhat offset in practice by the difficulty of its acquisition. This is why a number of computational linguists make a conscious choice to bypass ontology in their semantic deliberations. This decision is often justified by questioning the principles underlying ontologies and by challenging the ontology-based semantic enterprise on the grounds of its ostensible irreproducibility. In this paper we illustrate, on the example of the lexicon entry for the Spanish verb dejar, the expressive power of lexical-semantic descriptions based on the ontology used in the Mikrokosmos machine translation project. This expressive power is compared with that of some of the non-ontological approaches to lexical semantics. We argue that these approaches in reality rely on ontologies in ever...