OM_Observation used as property values

There are a couple of things that needs to be set in the way we encode OM_Observation, specially when we use them as property values.

There are two cases when we use OM_Observation as values
  1. When using relatedObservation on any sub types of SF_SamplingFeature
  2. Using a specific property (such as GW_FluidBody/gwBodyVolume)
OM_Observation has a mandatory featureOfInterest that is supposed to point back to the feature that is the “bearer of the property”. In case 2) , the bearer of the property is obviously the feature having this property, so technically, we should constrain featureOfInterest to link back to that feature

Eg: we should technically have this

obs_as_value.png

Issues: (Question in red)

Cases where the bearer of property is not a feature

(GW_WaterBudget for instance, is a Type, not a Feature), so we can’t use featureOfInterest to link it back

In this case, we should point back to the refers to this Type ? In case of WaterBudget, who does ?

Same Observation shared by multiple properties

nothing prevents more than one property to point to the same Observation (by reference), which becomes a problem for the featureOfInterest (foi is 1..1). It can be done schematically even if does not make sense logically. Should we have a clause that saysOM_Observation that are values of explicit properties will use featureOfInterest to identify the legitimate bearer of properties. Reference to OM_Observation from an explicit property when the property bearer is not the owner is invalid” (should it be invalid ?, or can it have another meaning)

ObservedProperty

OM_Observation also has an observedProperty. Technically, this should be a reference to the property (the property type, not a specific instance of the property) this observation is about. We have several options (which one should we use)
  1. Use a reference to schemas - like this "http://ngwd-bdnes.cits.nrcan.gc.ca/service/gwml/schemas/2.1/gwml2-well.xsd#GW_WellType.gwWellConstructedDepth (there are no good way to link to a property, it has no identity - (apparently, new ISO 19109 will change this)
  2. Use a good old vocabulary unrelated to domain schema - with the benefit of having more precise definition of the phenomena than the schema provide

-- EricBoisvert - 07 Jul 2015
Topic attachments
I Attachment Action Size Date Who Comment
obs_as_value.pngpng obs_as_value.png manage 6.2 K 07 Jul 2015 - 18:34 EricBoisvert observation as value
Topic revision: r1 - 07 Jul 2015, EricBoisvert
 

This site is powered by FoswikiThe information you supply is used for OGC purposes only. We will never pass your contact details to any third party without your prior consent.
If you enter content here you are agreeing to the OGC privacy policy.

Copyright © by the contributing authors. All material on this collaboration platform is the property of the contributing authors.
Ideas, requests, problems regarding OGC Public Wiki? Send feedback