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YounHee KIM ByungGon KIM HaeChull LIM
In the Semantic Web, metadata and ontology for representing semantics and conceptual relationships of information resources are essential factors. RDF and RDF Schema are the W3C standard models for describing metadata and ontology. In this paper, we focus on a result of analyzing available query patterns considering both RDF and RDF Schema. And we propose a structure to store and query using path information in graph models of RDF and RDF Schema. The proposed structure supports whole query patterns fairly. We can retrieve entities that are reached from a certain class, property, resource, or literal in RDF and RDF Schema without a loss of performance because of multiple joins with tables. And, through encoding schemes, we determine easily hierarchical relationships between classes or properties.
Hochong PARK Younhee KIM Jisang YOO
The AMR wideband speech codec was recently developed for high-quality wideband speech communications. Although it has an excellent performance due to expanded bandwidth of speech signal, it requires a huge amount of computation especially in codebook search. To solve this problem, this paper proposes an efficient codebook search method for AMR wideband codec. Starting from a poorly performing initial codevector, the proposed method enhances the performance of the codevector iteratively by exchanging the worst pulse in the codevector with a better one after evaluating the role of each pulse. Simulations show that the AMR wideband codec adopting the proposed codebook search method provides better performance with much less computational load than that using the standard method.