Wednesday, November 01, 2006
10:00 AM
CSB 632
Hermann Helbig
U. Hagen, Germany
Multilayered Extended Semantic Networks as a Knowledge Representation Paradigm and Interlingua for Meaning Representation
The talk gives an overview of Multilayered Extended Semantic Networks (abbreviated MultiNet), which is one of the most comprehensively described knowledge representation paradigms used as a semantic interlingua in large-scale NLP applications and for linguistic investigations into the semantics and pragmatics of natural language. As with other semantic networks, concepts are represented in MultiNet by nodes, and relations between concepts are represented as arcs between these nodes. Additionally to that, every node is classified according to a predefined conceptual ontology forming a hierarchy of sorts, and the nodes are embedded in a multidimensional space of layer attributes and their values. MultiNet provides a set of about 150 standardized relations and functions which are described in a very concise way including an axiomatic apparatus, where the axioms are classified according to predefined types. The representational means of MultiNet claim to fulfill the criteria of universality, homogeneity, and cognitive adequacy. In the talk, it is also shown how MultiNet can be used for the semantic representation of different semantic phenomena. To overcome the quantitative barrier in building large knowledge bases and semantically oriented computational lexica, MultiNet is associated with a set of tools including a semantic interpreter NatLink for automatically translating natural language expressions into MultiNet networks, a workbench LIA for the computer lexicographer, and a workbench MWR for the knowledge engineer for managing and graphically manipulating semantic networks. The applications of MultiNet as a semantic interlingua range from natural language interfaces to the Internet and to dedicated databases, over question-answering systems, to systems for automatic knowledge acquisition.