The IICS group at the University of Hagen employs multilayered extended semantic networks for the representation of background knowledge, queries, and documents for geographic information retrieval (GIR). This paper describes our work for the participation at the GeoCLEF task of the CLEF 2005 evaluation campaign (Cross Language Evaluation Forum). In our approach, geographical concepts from the ...

The use of ebs t rec t dete types as a basis f o r designing experimental knowledge representa t ion systems is discussed. Abst rect dete types ere shown to heve features in common w i t h severe l d iverse representat ion formalisms ( e . g . semantic networks, frames and KLONE). For example, ebs t rec t data types have not ions analogous to concept, subconcept end i nhe r i t ance . The r e l...

Given the numerous knowledge representation models (KR-schemes) that have been proposed, it would be desirable to have a formal, unifying model for the description of a KR-scheme, as well as a general method of comparing KR-schemes in terms of expressive power. This work attempts to fill this gap, by proposing an elegant, yet very general, model of describing KR-schemes. This formalization is u...

We present a formal description of a propositional semantic-network-based knowledge representation system. Variables in this representation are not atomic and have potentially complex structure. We start from the individual components of a semantic network system, atomics nodes and relations that connect nodes, and provide a complete speci cation for the structure of nodes and a subsumption pro...

OBJECTIVE To develop a semantic representation for clinical research eligibility criteria to automate semistructured information extraction from eligibility criteria text. MATERIALS AND METHODS An analysis pipeline called eligibility criteria extraction and representation (EliXR) was developed that integrates syntactic parsing and tree pattern mining to discover common semantic patterns in 10...

Semantic network approaches view organization or representation of internal lexicon in the form of either spreading or hierarchical system identified, respectively, as Spreading Activation Model (SAM) and Hi- erarchical Network Model (HNM). However, the validity of either model is amongst the intact issues in the literature which can be studied through basing the instruction compatible wi...