RE: ssn: action-155

FWIW All classes and most properties in om-lite have reasonably precise definitions in rdf:comment and dct:description properties.  Not formally axiomatized, but a lot more than just labels. For example oml:Observation is described:

An observation is an act associated with a discrete time instant or period through which a number, term or other symbol is assigned to a phenomenon [2]. It involves application of a specified procedure, such as a sensor, instrument, algorithm or process chain. The procedure may be applied in-situ, remotely, or ex-situ with respect to the sampling location. The result of an observation is an estimate of the value of a property of some feature. Use of a common model allows observation data using different procedures to be combined unambiguously.

The observation itself is also a feature, since it has properties and identity.

Observation details are important for data discovery and for data quality estimation.

The observation could be considered to carry metadata about an instance of a property (of the feature of interest). This property-value metadata complements the dataset and feature metadata that have been conventionally considered (e.g. ISO 19115).

The values for the properties 'procedure', 'featureOfInterest', 'observedProperty', 'phenomenonTime', 'resultTime' may be inherited from a container resource.



From: Krzysztof Janowicz []
Sent: Tuesday, 10 May 2016 5:29 AM
To: Kerry Taylor <>;
Subject: Re: ssn: action-155

Hi Kerry,

Sure. One of the reasons to include DUL in the original SSN was the need for a stronger semantic anchoring of the classes and relationships defined in SSN. One problem we faced was that terms such as Sensor, System, Observation, were under-specific to a degree where a major part of the intended interpretation of these classes was encoded in terms of their labels. DUL gave us additional axioms to further refine what was meant by 'Sensor', 'Observation' and so forth. Removing DUL, will leave us with the same problem as we had before, and, thus, I proposed to make use of the power of OWL2 to add a stronger axiomatic foundation to SSN (classes).


On 05/09/2016 05:20 AM, Kerry Taylor wrote:

Could you please address this remark you made in an ssn meeting some time ago? I read it as a suggestion for a major ssn rewrite, but perhaps it  is a suggestion for an extension instead?  Or something else?  It is sitting on this page  at present but maybe it deserves attention as one of these proposals on the wiki here  If nothing better can  you please explain it on the list so we can handle it appropriately and write it off the "task list" if appropriate?



Krzysztof Janowicz

Geography Department, University of California, Santa Barbara

4830 Ellison Hall, Santa Barbara, CA 93106-4060



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Received on Tuesday, 10 May 2016 01:06:51 UTC