SensorML OGC 12-000
Copyright © 2014 Open Geospatial Consortium
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4 Terms and Definitions
For the purpose of this document, the following terms and definitions apply: 4.1. Actuator
A type of transducer that converts a signal to some real-world action or phenomenon.
4.2. Aggregate Process
Composite process consisting of interconnected sub-processes, which can in turn be Simple Processes or themselves Aggregate Processes. An aggregate process can include possible data
sources. A decription of an aggregate process should explicitly define connections that link input and output signals of sub-processes together. Since it is a process itself, an aggregate process also
has its own inputs, outputs and parameters.
4.3. Coordinate Reference System CRS
A spatial or temporal framework within which a position andor time can be defined. According to ISO 19111, a coordinate system that is related to the real world by a datum.
4.4. Coordinate System CS
According to ISO19111, a set of mathematical rules for specifying how coordinates are assigned to points. In this document, a Coordinate System is extended to be defined as a set of
axes with which location and orientation can be defined.
4.5. Data Component
Element of sensor data definition corresponding to an atomic or aggregate data type Note: A data component is a part of the overall dataset definition. The dataset structure can then
be seen as a hierarchical tree of data components.
4.6. Datum
Undefined in ISO 19111. Defined here as a means of relating a coordinate system to the real world by specifying the physical location of the coordinate system and the orientation of the axes
relative to the physical object. For a geodetic datum, the definition also includes a reference ellipsoid that approximates the physical or gravitational surface of the planetary body.
4.7. Detector
Atomic part of a composite Measurement System defining sampling and response characteristic of a simple detection device. A detector has only one input and one output, both being scalar
quantities. More complex Sensors, such as a frame camera, which are composed of multiple detectors, can be described as a detector group or array using a System or Sensor model.
4.8. Determinand
