ELFIE Overview and Outcomes

David Blodgett: dblodgett@usgs.gov (For the ELFIE Team)
12/11/18

Environmental Linked Features Interoperability Experiment (ELFIE)

Demo:

https://opengeospatial.github.io/ELFIE/demo/uswb

Goals

  • Increase interoperability while decreasing data duplication and maintenance overhead
  • Combine the power of web services with transparency of linked data
  • Encode relationships between and among environmental features
  • Encode highly general “preview” content for any feature
  • Utilize commonly used and easily adopted approaches

Defining the problem... ELFIE was technical.

Current OGC services, while flexible and capable, do not directly allow exposure of features in a REST-ful way or provide traversable hypermedia describing available methods, data, or interfaces to related (linked) content.

  • REST-ful: GET + “accept: mime-type” gives you the mime-type if available
  • Hypertext: traversable web of text. Hypermedia: traversible web of data
  • methods, data, interfaces: getCapabilities, describeFeaturetype, etc.
  • related (linked) content: things or data that are related from other services

Linked data graph views

Linked data graph views

Monitoring, and domain data models

  • Sensors, Observations, Samples and Actuators (SOSA)
  • Timeseries Markup Language (TimeseriesML)
  • Surface Hydrology Features (HY_Features)
  • Growndwater Markup Language 2 (GWML2)
  • Geoscience Markup Language 4 (GeoSciML)
  • Soil Data Interoperability Experiment (SoilIEML)
  • Floodcast (Experimental)

Use Cases: Watershed Data Index

Use Cases: US Water Budgets

Use Cases: Surface-Ground Water Networks Interaction

Use Cases: Ground Water Monitoring

Use Cases: FloodCast

Outcomes

(note links on this slide are live)

Findings

  • WFS 3 should be well suited to the needs of ELFIE use cases
  • Ontologies for existing and pending data standards need to be published.
  • Data providers need to publish URIs for their features or this won't work.
  • Future work needs to consider how to discover “views” of a given feature.

HTTP Range-14 and Cool URIs:

  • Http URIs (http://bing/bang/boom/) usually identify a specific digital resource
  • Http URIs can also be identifiers for non-digital things, e.g. rivers, wells, etc
  • Hyper text transport protocol (http) as a function whose domain is a URI
  • The range of http is usually the digital resource identified by a URI.
  • For a URI that identifies a non-digital thing… the range of the http function is undefined.

Enter Cool URIs

Cool URIs Resolve – for a non-digital thing they resolve a 303-see other.

But then what?!?!?

To Be Continued…

Join the Second Environmental Linked Features Interoperability Experiment

(SELFIE)