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Why are Ontologies Important ?
Luis Bermudez QARTOD III November 2-4, 2005
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Ontology-Philosophy

• Most fundamental branch of metaphysics. It
  studies being or existence as well as the basic
  categories thereoftrying to find out what
  entities and what types of entities exist.
• - Wikipedia

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• Because any ontology is, among other things, a
  social / cultural artifact, there is no purely
  objective perspective from which to observe the
  whole terrain of concepts. Instead of asking,
  what hierarchical representation of concepts
  best captures the universal relationships among
  general ideas, it is more productive to ask
  what specific purpose do we have in mind for
  this conceptual map of entities and what
  practical difference will this ontology make?
• -Wittgenstein, Tractatus Logico-Philosophicus.

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SWEET Ontologieshttp//sweet.jpl.nasa.gov/ontolog
y/

• Earth Realms
• Physical Phenomena
• Physical Processes
• Physical Properties
• Physical Substances
• Sun Realms
• Biosphere

• Data
• Data Centers
• Human Activities
• Material Things
• Numerics
• Sensors
• Space
• Time
• Units

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Ontologies - Computer ScienceSpecification of
conceptualizations
Example 1. Properties of real world objects are
identified. 2. Similarities are identified. 3.
Concepts are created 4. and are expressed as a
class. 5. Classes are related.
Is inland body
Has a relative defined channel
Has water
Body of Water
Class
Subclass
River
Lake
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Hydrologic Unit
Mid Atlantic
Delaware
Lower Delaware
Subclasses
Schuylkill
Instances
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What is an Ontology?
Thesauri narrower term relation
Frames (properties)
General Logical constraints
Formal is-a
Catalog/ ID
Informal is-a
Formal instance
Disjointness, Inverse, part-of
Terms/ glossary
Value Restrs.
Deborah McGuinness
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Why Ontologies

• To share common understanding of the structure of
  information among people or software agents
• To enable reuse of domain knowledge
• To make domain assumptions explicit
• To separate domain knowledge from the operational
  knowledge
• To analyze domain knowledge

Cartic Ramakrishnan LSDIS Lab, University of
Georgia
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Why do we have a presentation about ontologies in
a QARTOD meeting ?
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Do we need to share explictly QARTOD concepts ?

• Quality Levels
• Flags
• Sensors
• Instrument Methodology
• Calibration procedures
• QC software procedures
• Methods of verification and validation
• Methods for manual checking
• Malfunctions

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Can we state this explictly ?
WHP CTD data quality codes
WMO IGOSS observation quality codes
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MMI and ontologies
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Semantic Issues
Search for seatemperature data
GCMD
GCMD
Sea surface Temperature
Ocean Temperature
CF
sea_water_ temperature
Dont sure what data will get retrieved ?
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Solving semantic issues
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Harmonization
HTML
Comma Separated Values
DTD
Tab Separated Values
XML/XSD
OWL
Relational Database
RDF
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Web Ontology Language OWL

• W3C Recommendation 02/04.
• Based on RDF. (-gt URI )
• Inference capabilities.
• Restriction of inherit properties.
• Can be used to express specifications and
  vocabularies

Body of Water
River
ltowlClass rdfIDBody_of_Watergtlt/owlClassgt lto
wlClass rdfIDRivergt ltrdfssubClassOf
rdfresource Body_of_Water/gt lt/owlClassgt
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Domain Ontologies Repository
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VOC2OWL
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VINE Vocabulary Integration Environment
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Community role
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Mapping Results
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http//marinemetadata.org
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Ingests from instruments
Data Source
processes formats/archives
sends
gets
Community
gets
Guides Tools
sends
Technology
processes formats/archives
processes uses/analyzes
gets
publishes
Data User
Data Provider
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About MMI

• MMI Marine Metadata Interoperability
  Initiative.
• NSF funded and SURA (Southeastern Universities
  Research Association) supported.
• Initially one year project (September 2005). In
  the process of getting extended (NOAA and NSF).
• Organization Executive committee (5), Steering
  committee (17), technical committee(25), and
  contributors. Community of more than 200 members
• (October 2005).
• Deliverables
• Community web site with metadata content,
  guidance
• Interoperability Demonstrations
• Workshop Advancing Domain Vocabularies
• Tools VINE Voc2OWL, Tethys, Web Services

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http//marinemetadata.org/tethys

• Implement two methods and make them available
  using SOAP web services.
• Convert the parameters, sources, and units used
  in their system to an ontology.
• (tool VOC2OWL ascii to OWL)
• Map the terms used in the system to the MMI
  preferred ontology Standard vocabulary for
  discovery (GCMD) and for usage (CF).

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Steering Committee Members

• John Graybeal, MBARI. PI. (ExecComm) graybeal_at_mbar
  i.org
• Stephanie Watson, CeNCOOS. (ExecComm) swatson_at_mbar
  i.org
• Philip Bogden, SURA/SCOOP. (ExecComm) bogden_at_gomoo
  s.org
• Stephen Miller, Scripps. (ExecComm) spmiller_at_ucsd.
  edu

• Robert Arko, LDEO
• Julie Bosch, NOAA
• Francisco Chavez, MBARI
• Ben Domenico, Unidata
• Karen Stocks, SDSC
• Steve Hankin, NOAA - Ocean.US/DMAC

• Roy Lowry, BODC
• Mark Musen, Stanford Univ
• Michael Parke, Univ of Hawaii
• Lola Olsen, NASA Goddard
• Dawn Wright, Oregon State Univ
• Bob Weller, WHOI

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Credits

• National Science Foundation1
• SURA, the Southeastern Universities Research
  Association (http//www.sura.org),
• NOAA (including the Coastal Services Center),
• ONR, the Office of Naval Research
  (http//www.onr.navy.mil),
• OceanUS and regional IOOS systems.
• 1 NSF Grant ATM-0447031

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Thank you !bermudez_at_mbari.orgask_at_marinemetadat
a.org