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sosa:Observation

#SOSA#RDF Class#Observation#Entity Detail

The sosa:Observation class represents the act of observing a property or phenomenon using a sensor, sampler, or procedure. In SDL, sosa:Observation is used to model the results of scientific measurements or analyses performed on physical samples or environments.


Definition

URI: http://www.w3.org/ns/sosa/Observation

A sosa:Observation is an act that results in the determination of the value of a property of a feature of interest.


Usage in SDL

In SDL, sosa:Observation is used to:

  • Capture measurement events and analytic results
  • Link samples or features of interest to observed properties
  • Associate values, units, time, and responsible agents with recorded results
  • Trace provenance of derived data products

Observations are often treated as prov:Entity to support attribution and workflow traceability.


Properties

Property Description Optional
sosa:hasFeatureOfInterest The entity whose property is being observed No
sosa:observedProperty The property that is being measured or described No
sosa:hasResult The value or outcome of the observation No
sosa:madeBySensor The sensor or system that performed the observation Yes
sosa:usedProcedure Procedure followed to obtain the observation Yes
sosa:resultTime Timestamp when the result became available Yes
sosa:phenomenonTime Time at which the observed phenomenon occurred Yes
prov:wasGeneratedBy Activity that generated the observation Yes
prov:wasAttributedTo Agent responsible for the observation Yes
dcterms:identifier Identifier for the observation Yes
dcterms:title Human-readable title Yes
dcterms:description Description or notes about the observation Yes

Composition

Observations in SDL may:

  • Be associated with one or more sosa:Sample, prov:Activity, or prov:Agent
  • Be used as evidence for derived datasets
  • Serve as entries in catalogs via dcat:Resource
ex:obs1 a sosa:Observation , prov:Entity ;
  sosa:hasFeatureOfInterest ex:sampleA ;
  sosa:observedProperty ex:ph ;
  sosa:hasResult ex:result7_2 ;
  sosa:madeBySensor ex:probe1 ;
  sosa:resultTime "2024-04-15T10:30:00Z"^^xsd:dateTime .

Example — Observation with Sample and Result

ex:sampleA a sosa:Sample ;
  dcterms:title "Soil Sample from Plot A" .

ex:result7_2 a qudt:QuantityValue ;
  qudt:numericValue "7.2"^^xsd:decimal ;
  qudt:unit qudt:PH-UNIT .

ex:obs1 a sosa:Observation , prov:Entity ;
  sosa:hasFeatureOfInterest ex:sampleA ;
  sosa:observedProperty ex:ph ;
  sosa:hasResult ex:result7_2 ;
  sosa:resultTime "2024-04-15T10:30:00Z"^^xsd:dateTime ;
  prov:wasGeneratedBy ex:activity3 ;
  prov:wasAttributedTo ex:labTech1 .

  • sosa:Sample — may be the feature of interest
  • prov:Activity — generating process
  • qudt:QuantityValue — type of result used in scientific observations
  • dcat:Resource — observations may be cataloged or referenced

See Also

sosa:Observation enables granular, semantically rich modeling of scientific measurements in SDL. It supports provenance, cataloging, and data integration across disciplines.