Semantic Web underpinnings of the IRI Data Library Semantic Web as a Framework for Multiple Metadata IRI Data Library: presenting Data in multiple frameworks Pure RDF Faceted Data Search Metadata interoperability using adiabatic XML Schema to OWL mapping

blind monks examining an elephant John Godfrey Saxe ( ) Multiple partial representations of objects described by data

Semantic Web as a Framework for Multiple Metadata: The Data Problem Users Datasets

The Tool Interface Users Datasets Tools

Standard Metadata Users Datasets Tools Standard Metadata Schema/Data Services

Many Data Communities Tools Users Datasets Standard Metadata Schema Tools Users Datasets Standard Metadata Schema Tools Users Datasets Standard Metadata Schema Tools Users Datasets Standard Metadata Schema Tools Users Datasets Standard Metadata Schema

Super Schema Tools Users Datasets Standard Metadata Schema Tools Users Datasets Standard Metadata Schema Tools Users Datasets Standard Metadata Schema Tools Users Datasets Standard Metadata Schema Tools Users Datasets Standard Metadata Schema Standard metadata schema

Tools Users Datasets Standard Metadata Schema RDF Tools Users Datasets Standard Metadata Schema RDF Tools Users Datasets Standard Metadata Schem RDF RDF Data Model Exchange RDF Tools Users Datasets Standard Metadata Schema RDF Tools Users Datasets Standard Metadata Schema RDF

RDF Architecture RDF Virtual (derived) RDF queries

Where we are coming from – the IRI Data Library presenting Data in multiple frameworks

IRI Data Library Overview IRI Data Collection Generalized Data Tools Specialized Data Tools Dataset Variable ivar multidimensional Data Viewer Data Language Maproom URL/URI for data, calculations, figs, etc

Data Flow based Analysis with explicit semantics Results data analysis Data analysis Semantic Web

IRI Data Collection Dataset Variable ivar multidimensional Economics Public Health “geolocated by entity” GIS “geolocation by vector object or projection metadata” Ocean/Atm “geolocated by lat/lon” multidimensional spectral harmonics equal-area grids GRIB grid codes climate divisions IRI Data Collection

IRI Data Collection Dataset Variable ivar Servers OpenDAP THREDDS GRIB netCDF images binary Database Tables queries spreadsheetsshapefiles images w/proj IRI Data Collection

IRI Data Collection Dataset Variable ivar Calculations “virtual variables” images graphics descriptive and navigational pages OpenGIS WMS/WCS KML Data Files netcdf binary images Clients OpenDAP THREDDS Tables Servers OpenDAP THREDDS GRIB netCDF images binary Database Tables queries spreadsheetsshapefiles images w/proj IRI Data Collection

IRI General Data Tools Data Page

IRI General Data Tools Data Viewer

Calculations: svd (link: svdview) (link: svd results dataset) (link: svd documentation)

WMS and KML: land cover (link:figure page)

Malaria Early Warning System Front page illustrates most recent dekadal rainfall estimates (FEWS RFE) Change dates to view different time periods Administrative and epidemiological overlays available Click and drag box across map to zoom IRI Map Room

IRI Data Library Faceted Search: an example of RDF-based faceted search for climate data Drawing on multiple ontologies to build an application Using inference to connect ontologies describing different parts of the framework

Search Interface as Multiple Ontologies Search Interface Users Datasets Search Ontology Dataset Ontology Additional Semantics

Faceted Search

Distinctive Features of the search Search terms are interrelated terms that describe the set of returns are displayed (spanning and not) Returned items also have structure (sub- items and superseded items are not shown)

Architectural Features of the search Interface is generated from a set of Terms connected to a set of Items Multiple search structures possible Multiple languages possible Search structure is kept in the database, not in the code

Term Ontology Concepts as individuals (unlike conceptual ontology with concepts as classes) Simple Knowledge Organization System (SKOS) is a prime example The ontology used here is slightly different than SKOS: facets are classes of terms rather than being top_concepts

Nuanced tagging Concepts as objects can be interrelated: specific terms imply broader terms Object ends up being tagging with terms ranging from general to specific. Search can then be nuanced tagging can proceed in absence of perfect information

Faceted Search Explicated

Search Interface Items (datasets/maps) Terms Facets Taxa

Search Interface Semantic API {item} dc:title dc:description rss:link iridl:icon dcterm:isPartOf {item2} dcterm:isReplacedBy {item2} {item} trm:isDescribedBy {term} {term} a {facet} of {taxa} of {trm:Term}, {facet} a {trm:Facet}, {taxa} a {trm:Taxa}, {term} trm:directlyImplies {term2}

Faceted Search w/Queries

RDF Architecture RDF Virtual (derived) RDF queries

Data Servers Ontologies MMI JPL Standards Organizations Start Point RDF/XML-Schema Crawler XML Schema to OWL translation Owl Semantics SWRL Rules SeRQL CONSTRUCT Search Queries Location Canonicalizer Time Canonicalizer Sesame Search Interface bibliography IRI RDF Architecture

Cast of Characters NC – netcdf data file format CF – Climate and Forecast metadata convention for netcdf (includes controlled vocabulary for physical quantities) SWEET - Semantic Web for Earth and Environmental Terminology (OWL Ontology) IRIDL – IRI Data Library

CF attributes SWEET Ontologies (OWL) Search Terms CF Standard Names (RDF object) IRIDL Terms NC basic attributes IRIDL attributes/objects SWEET as Terms CF Standard Names As Terms Gazetteer Terms CF data objects Location

XML Schema to OWL ontologies Semantically-mediated translation between Web Coverage Service (WCS) and OPeNDAP (data as multiple-dimension variable) WCS is defined in XML Schema (57!) Sample Schema to OWL Translation Method to return JDOM element (XML) containing requested XML property from RDF triple-store (element maps to (Resource,class) pair) Sample Datasets/Coverages

Please Visit IRI Data Library: IRI ontology work: Or contact: Benno Blumenthal John del Corral Haibo Liu