Time series observation specialisations Requirements class – Timeseries domain range Observation Requirements Class

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9.4.1.8.5 maximumGap

Maximum gap provides information on the joining of different observations into a larger series. See section 9.15.2.2 for more information.

9.5 Time series observation specialisations

The core TimeseriesObservation is restricted in two specialised types that represent the two possible timeseries result structures: domain-range and time-value pairs. See section 9.12 for details on the definition of the timeseries types. Note: The TimeseriesObservation does not directly subclass the OM_TimeseriesObservation from ISO19156 as this type restricts the result to a CVT_DiscreteTimeInstantCoverage, which is a style of TVP timeseries and thus would not allow the domain-range style of timeseries. Future work will attempt to harmonise the definition of timeseries across the ISOOGC standards. Figure 10 shows the relationship between the time-value pair structuring of timeseries with the CVT_DiscreteTimeInstantCoverage type. The WaterML2.0 TimeValuePair type makes the specialisation of the DomainObject to a temporal component explicit through the WML_DomainObject. The two types reflect different styles of representing timeseries observations. Figure 9 - Observation types as related to ISO19156 green and ISO19123 red «FeatureType» TimeseriesObserv ation «FeatureType» TimeseriesDomainRangeObserv ation «FeatureType» Timeseries TVP Observ ation:: TimeseriesTVPObserv ation «FeatureType» observ ation::OM_Observ ation «FeatureType» cov erageObserv ation:: OM_DiscreteCov erageObserv ation CV_Coverage «type» Discrete Coverages:: CV_DiscreteCoverage «FeatureType» Timeseries Domain Range:: TimeseriesDomainRange «FeatureType» Interleav ed TVP Timeseries:: TimeseriesTVP «FeatureType» Timeseries::Timeseries +result +result 0.. +relatedObservation 0.. +result Range Range +result Copyright © 2012 Open Geospatial Consortium 28 Figure 10 - Relationship to CVT_TimeInstantCoverage ISO19156 – Annex C, green

9.6 Requirements class – Timeseries domain range Observation Requirements Class

http:www.opengis.netspecwaterml2.0requml-timeseries-domain-range-observation Target Type Encoding of the conceptual model Name Time series domain range observation Dependency http:www.opengis.netspecwaterml2.0requml-timeseries-observation Dependency http:www.opengis.netspecwaterml2.0requml-timeseries-domain-range Requirement requml-timeseries-domain-range-observationresult A TimeseriesDomainRangeObservation shall have a result of type TimeseriesDomainRange, as defined in section 9.13 of this standard. This is represented in the UML in Figure 9 . 9.6.1.1 result OM_Observation The result of a TimeseriesDomainRangeObservation is restricted to be of type TimeseriesDomainRange as defined in section 9.13. «DataType» TimeValuePair + geometry :WML_DomainObject «FeatureType» TimeseriesTVP Temporal Cov erage:: CVT_DiscreteTimeInstantCov erage «DataType» Temporal Cov erage:: CVT_TimeInstantValuePair + geometry :TM_Instant CV_Coverage «type» Discrete Coverages::CV_DiscreteCoverage + locateDirectPosition :SetCV_GeometryValuePair Cov erage Core:: CV_GeometryValuePair + geometry :CV_DomainObject + value :Record «FeatureType» Timeseries::Timeseries +collection 0.. CoverageFunction +element 0.. +element 0.. CoverageFunction +collection 0.. +element 0.. CoverageFunction +collection 0.. OGC WaterML 2.0 OGC 10-126r3 Copyright © 2012 Open Geospatial Consortium 29

9.7 Requirements class – Measurement Timeseries domain range Observation Requirements Class