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Univ. of Crete & ICS-FORTH NIT’98, Athens, Greece
THETIS: A Data Management and Data Visualization
system for supporting Coastal Zone Management (CZM) of the Mediterranean Sea
Catherine Houstis
Institute of Computer Science Foundation for Research and Technology -
HellasComputer Science Dept. Univ. Of Crete
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Univ. of Crete & ICS-FORTH NIT’98, Athens, Greece
THETIS: The Project
Objectives: Integrate heterogeneous scientific repositories for CZM into an
interoperable system for transparent access via the Web Index/Search and Querying of heterogeneous repositories
Files, images, documents, text, audio Scientific programs (simulation models, image/data processing
algorithms) Visualization via GIS and scientific tools User groups scientists and public authorities
Consortium: 9 Partners: university, research institutions , IT companies
Duration: 21/2 years, 1998-2001 First Prototype available online in four countries UK, FR, IT, GR
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Univ. of Crete & ICS-FORTH NIT’98, Athens, Greece
THETIS: Design Considerations
Index/Search: use of Dienst (DL search engine) Discover resources (keywords, geographic location, time, by name) Management of Metadata (FGDC standard, varying #of search fields) Distributed Indexing/Search (strings(multilingual),numbers)
Querying:use of Le Select (DB Integration engine) Mediation (data files, image database,documents,programs)
JDBC access Data Transformations, integration and manipulation
SQL queries Wrapping of repositories
Light Weight Workflow: Interactive (via index)
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Univ. of Crete & ICS-FORTH NIT’98, Athens, Greece
THETIS: The Architecture
Web ClientWeb Client Web ServerWeb Server
Session ManagerSession ManagerAppletsAppletsAppletsApplets
Le SelectLe Select DienstDienstMetadataMetadata
Data Programs Documents
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Univ. of Crete & ICS-FORTH NIT’98, Athens, Greece
Dienst: the index/search engine
Distributed Architecture Repository Service Index Service UI Service Meta Service
WWW Client Interface
HTTP both for client-server & server-server communication
UI serverRepository
server
HTTP
clientsclients
Index server
Dienst Server
DS
DS
DS
other Dienst servers
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Univ. of Crete & ICS-FORTH NIT’98, Athens, Greece
Dienst: the index/search engine (cont.)
Monitoring tools flow monitor performance monitor monitoring other dienst servers
Metadata (FGDC, content, geographical location, time) parameterized input
determination of collection objects determination of search, browse, index fields workflow information (interactive, rule based) pricing mechanism (repository service, QoS, system congestion)
User Interface web access GIS access (thematic maps, animation)