1. Improvement of Semantic Interoperability based on Metadata Registry(MDR) Doo-Kwon Baik Dept. of CSE Korea University

2. Introduction In DL, Federation of Index DB and Local DB is essential. Heterogeneity  Schema Level(Data Element Level)  Various Metadata Encoding Format  Dublin Core, USMARC, KOMARC  Schema of Local DB  Terminology(Data Value Level)  Semantic Heterogeneity, bi-lingual

3. Why Metadata Needs? users and implementors need  a dictionary of terms  a place to publish project- or discipline-specific adaptations to share with colleagues and partners metadata needs  to manage its namespace (as a standards agency)  to provide machine-readable schemas for loading into editors and search engines  to provide crosswalks to related schemas  to link the (english) standard to translations in other languages

4. Information Retrieval System based on Metadata Registry(1) User Interface Schema Repository MDR Query Processor Analyzer Transformer Executer Integrator Digital Object Database B Digital Object Database A Metadata Dublin Core Metadata KOMARC Terminology Manager MDR Manager Schema Repository Manager TRS Sub Query & Result User Query & Result Sub Query & Result

5. Information Retrieval System based on Metadata Registry(2) Characteristics  Conceptual integration of index and local DB ’ s  Semantic interoperability based on  MDR(Metadata Registry)  SR(Schema Repository)  TRS(Terminology Reference System)

6. Metadata Registry(MDR) ISO/IEC 11179 – Metadata Registry  Framework for the Specification and Standardization of Data Elements  Classification of Data Elements  Metamodel of MDR  Rules and Guidelines for the Formulation of Data Definitions  Naming and Identification Principles for Data Elements

7. Metadata Registry Object Class Property Data Element Concept 1:N 1:1 Object Class Property Data Element 1:N 1:1 Representation 1:1

8. Schema Repository Mapping local schema and semantic to MDR Metadata Registry Data Element Concept Data Element Schema Repository Local DB1 Schema Local DB 2 Schema Global Schema LDB1 LDB2

9. Terminology ConceptTermsContext Common name Scientific name Korean name trout Salmo trutta 송어 Any of several game fishes of the genus Salmo, related to the salmon

10. Terminology Reference System ConceptTermsContext Common name Scientific name Korean name trout Salmo trutta 송어 Local Mapping TRS  Query Processor 

11. Summary(1) Information Integration Problem of DL  Interoperability of heterogeneous DBs  Interoperability of multi-lingual DBs Solution of Information Integration Problem  MDR (Metadata Registry)  SR (Schema Repository)  TRS (Terminology Reference System)

12. Summary(2) Needs of International Co-Work  Exchange of Research results  Discovery of cultural differences in the description of metadata  Improvement of Semantic Interoperability  Multi-lingual Extension of MDR  Multi-lingual Support of TRS  Sharing of Experimental Data Sets