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The featureOfInterest FOI is a feature of any type ISO 19109, ISO 19101, which is a representation of the observation target, being the real-world object
regarding which the observation is made
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The observedProperty identifies or describes the phenomenon for which the observation result provides an estimated value. It must be a property associated
with the type of the feature of interest.
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The procedure is the description of a process used to generate the result. It must be suitable for the observed property.
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The result contains the value generated by the procedure. Note:
The schema of the result data is not determined by the OM model. The SensorSA recommends a self-describing schema, e.g. by using the definitions
of the SWECommon specification.
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As further properties, an observation may have meta-information, e.g. the responsible actor for the observation and an indication of the event-specific quality.
«FeatureType»
Observ ation
+ metadata: MD_Metadata [0..1] + samplingTime: TM_Object
+ resultTime: TM_Object [0..1] + resultQuality: DQ_Element [0..1]
+ parameter: Any [0..]
constraints
{observedProperty must be member or component of member of featureOfInterest}
{procedure must be suitable for observedProperty} {result type must be suitable for observedProperty}
«FeatureType»
Process
«FeatureType»
AnyFeature
«type»
Any
{n}
PropertyType
«metaclass»
GF_FeatureType
{n} + definition: CharacterString
+ isAbstract: Boolean = false + typeName: LocalName [0..1]
«metaclass»
GF_PropertyType
{n} + definition: CharacterString
+ memberName: LocalName «FeatureType»
Observ ationCollection
member 1..
generatedObservation 0..
procedure 1
propertyValueProvider 0..
featureOfInterest 1
result observedProperty
1 «instanceOf»
1
carrierOfCharacteristics 0..
«instanceOf»
Figure 7-1: Information Model Observation Measurement from OGC 07-022
7.3. Information Model of the Sensor Observation Service
The information model that underpins the Sensor Observation Service SOS see its description in section 8.2.2 follows the concepts of the OM Model previously described in
section 7.2. The resulting SOS information model is illustrated in Figure 7-2.
SANY D2.3.4 Specification of the Sensor Service Architecture V3 Doc.V3.1
Copyright © 2007-2009 SANY Consortium Page 103 of 233
The SOS collects observations in a concept called observation offering. An observation offering
is specified by instances of the related OM concepts observation, observed properties
which points to a phenomenon, procedure and feature of interest. Observations and procedures can be part of more than one offering. Further properties of an observation
offering are its name, the temporal context time period and the spatial context region. The spatial context of the offering is usually defined as a bounding box which includes all
locations where observations are taken.
The OM concept of a procedure abstracts from the source that produces the value of an observation. This may involve a sensor as a technical device see the technology viewpoint
of the SANY Sensor Model in section 5.2, an analytical procedure, a simulation or other numerical processes.
The following describes how the SOS operations use the concepts of the SOS information model.
The getCapabilities operation is used to discover the observations provided by an SOS and returns the service capabilities. Detailed information is included about all available
observation offerings . This comprises the observed properties, procedures and feature of
interest included in the offering where
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A procedure is used to produce an estimate for an observed property.
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A phenomenon and the related unit of measurement are defined by a URI Universal Resource Identifier.
Note: Details of the phenomenon and the unit may be defined in a dictionary.
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The feature of interest is a single feature instance or a collection of feature instances that represent the object on which the observations are made. The feature of interest
may have a location property that is expressed in GML.
Note: Different GML feature types are allowed. All such features are expected to include the optional boundedBy element with a GML envelope if the
location is known.
Notes: 1. In Figure 7-2, the associations used to resolve the getCapabilites request are
shown in green. 2. The getCapabilities operation does not return information on the relationship
between a sensor and its measured phenomena or between a procedure sensor and the related feature of interest.
The SOS operation getFeatureOfInterest is used to obtain detailed information such as the location of features of interest, as in all other operations the feature of interest is only
referenced by its identifier. The consumer of an SOS uses the getObservation operation to retrieve observation data
for an observation offering as instances of the concept observation defined by the OM specification see section 7.2.:
SANY D2.3.4 Specification of the Sensor Service Architecture V3 Doc.V3.1
Copyright © 2007-2009 SANY Consortium Page 104 of 233
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An observation is an event and contains an eventTime that describes the time at which the observation has been taken. An observation is also related to the procedure that
estimated the value.
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It is bound to the feature of interest which describes the feature for which the observation was taken.
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An observation captures one or more observed properties. The observations can also be requested for a set of observed properties or a set of procedures within the
observation offering.
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An observation from a procedure only contains observed properties which are included in the output section in the corresponding SensorML document. The output
section of SensorML describes the observed properties of the sensor that has produced the observation values.
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The user can further restrict the amount of data returned by using temporal or spatial filters. The allowed filter types are reported by the getCapabilities operation.
SANY D2.3.4 Specification of the Sensor Service Architecture V3 Doc.V3.1
Copyright © 2007-2009 SANY Consortium Page 105 of 233
class Sos
Observ ation Offering
Name: region:
TimePeriod:
observ ed Property
Feature of Interest
location: GML Name:
Procedure SOS
getCapabilities describeSensor
GetObservation
Observ ation
Time:
SensorML
Output Input
Identification
Classification
Location
this can be a single or composite property
Feauture where
observation was taken
1 1..
output is 1..
1.. procedure
is bound to
1 1..
1 1..
1.. 1..
is described by 1..
1.. 1
1.. 1..
1
Figure 7-2: Information Model of the Sensor Observation Service
SANY D2.3.4 Specification of the Sensor Service Architecture V3 Doc.V3.1
Copyright © 2007-2009 SANY Consortium Page 106 of 233
7.4. Access Control Information Model
