SWE terms

From Semantic Sensor Network Incubator Group
Revision as of 21:16, 14 July 2010 by Llefort (Talk | contribs)

(diff) ← Older revision | Latest revision (diff) | Newer revision → (diff)
Jump to: navigation, search

N.B. This is basically an amalgam of terms in OGC-0700 (SensorML) and OGC 07-022r1 (O&M). I have not fastidiously edited it to make it more useful/applicable! Given I'd created the list elsewhere for a similar exercise I thought it might be a helpful starting/calibration point (krp 200910)

N.B. (Laurent): At Simon's request, I have checked in the updated definitions from O&M 2.0 (ISO 19156, ISO/TC 211 document ref. N 2921)


Actuator (SensorML): A type of transducer that is a simple element that converts a signal to some action or real world phenomenon. In SensorML a actuator is a particular type of Process Model.

  • 20091222 - Laurent_Lefort: Decide if actuators are inside scope or out of scope

actuator (IEEE P1451): A transducer that accepts an electrical signal and converts it into a physical action.

analyte (O&M): species whose concentration is subject to observation. Specialization of observable property-type.

  • 20091222 - Laurent_Lefort: observable property-type not defined!
  • 20091222 - Laurent_Lefort: Specialization of Determinand
  • 20091222 - Laurent_Lefort: chemical compounds/determinands are specified but not taxa/biological determinands

Coordinate Reference System (CRS) (SensorML), coordinate reference system (O&M): A spatial or temporal framework within which a position and/or time can be defined. A coordinate system that is related to the real world by a datum (ISO 19111).

  • 20091222 - Laurent_Lefort: can we use a definition sourced from EPSG?

Coordinate System (CS) (SensorML): According to ISO19111, a set of (mathematical) rules for specifying how coordinates are assigned to points (ISO 19111). In this document (SensorML), a Coordinate System is extended to be defined as a set of axes with which location and orientation can be defined.

  • 20091222 - Laurent_Lefort: (SensorML) add-on not needed.
  • 20091222 - Laurent_Lefort: can we use a definition sourced from EPSG?

coverage (O&M): feature that acts as a function to return values from its range for any direct position within its spatiotemporal domain (ISO 19123)

  • 20091222 - Laurent_Lefort: can be interpreted in multiple ways. Is coverage a sub-class of result? Is coverage disjoint with "real world" features?

coverage: (ISO TC211)

data type (O&M): specification of a value domain with operations allowed on values in this domain ISO/TS 19103 Example: Integer, Real, Boolean, String, Date (conversion of a data into a series of codes). NOTE: Data types include primitive predefined types and user-definable types. All instances of a data types lack identity.

  • 20091222 - Laurent_Lefort: would prefer a definition which covers ISO 1900 series + XML + RDF concepts of datatypes

Datum (SensorML): 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 approximate the surface of the planetary body.

  • 20091222 - Laurent_Lefort: can we use a definition sourced from EPSG?

Detector (SensorML): 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. In SensorML a detector is a particular type of Process Model.

  • 20100201 - Laurent_Lefort: IEEE P1451 does not define detector.

Determinand (SensorML), determinand (O&M): parameter or a characteristic of a phenomenon subject to observation. Synonym for observable propertyType.

  • 20091222 - Laurent_Lefort: Determinand has two usages. It can be used as a generic concept (where it is equivalent to observable propertyType or "parameter") or in conjunction with Medium (e.g. for Water quality observation) where it plays the role of superclass for a range of alternative characteristics (or constituents) which qualifies the observation: analyte, taxa, ... .

feature (O&M): abstraction of real world phenomena (ISO 19101)

NOTE: A feature may occur as a type or an instance. Feature type or feature instance should be used when only one is meant.

  • 20091222 - Laurent_Lefort: Feature is difficult to map to upper ontologies like DOLCE: is it an Endurant or a Perdurant or both?

feature type: (O&M) class of features having common characteristics

Location (SensorML): A point or extent in space relative to a coordinate system. For point-based systems, this is typical expressed as a set of n-dimensional coordinates within the coordinate system. For bodies, this is typically expressed by relating the translation of the origin of an object’s local coordinate system with respect to the origin of an external reference coordinate system.

Location Model (SensorML): A model that allows one to locate objects in one local reference frame relative to another reference frame.

  • 20091222 - Laurent_Lefort: Is this a sub-class of CRS?

Measurand (SensorML): physical parameter or a characteristic of a phenomenon subject to a measurement, whose value is described using a Measure (ISO 19103). Specialization of observable property-type.

  • 20091222 - Laurent_Lefort: see VIM definition below

Measurand (O&M): particular quantity subject to measurement.

  • 20100714 - Laurent_Lefort: O&M 2.0 definition (more concise)

Measure (SensorML), (O&M): value described using a numeric amount with a scale or using a scalar reference system (ISO/TS 19103)

NOTE: When used as a noun, measure is a synonym for physical quantity.

  • 20091222 - Laurent_Lefort: VIM uses Quantity value or indication

Measurement (O&M): set of operations having the object of determining the value of a quantity [ISO/TS 19101-2:2008, definition 4.20]

  • 20100714 - Laurent_Lefort: (new) O&M 2.0 definition

Measurement (noun) (SensorML): an observation whose result is a measure

  • 20091222 - Laurent_Lefort: avoid this definition - use Observation instead
  • 20091222 - Laurent_Lefort: disagree with the noun vs. verb distinction made by SensorML. Measurement should only be used for the process/procedure of measuring

Measurement (verb) (SensorML): An instance of a procedure to estimate the value of a natural phenomenon, typically involving an instrument or sensor. This is implemented as a dynamic feature type, which has a property containing the result of the measurement. The measurement feature also has a location, time, and reference to the method used to determine the value. A measurement feature effectively binds a value to a location and to a method or instrument.

Observation (SensorML), (O&M): act of observing a property

NOTE The goal of an observation may be to measure or otherwise determine the value of a property

  • 20100714 - Laurent_Lefort: using O&M 2.0 definition which is more concise

observation procedure tt>(O&M)</tt>: method, algorithm or instrument, or system of these which may be used in making an observation

  • 20100714 - Laurent_Lefort: O&M 2.0 definition

observation protocol tt>(O&M)</tt>: combination of a sampling strategy and an observation procedure used in making an observation

  • 20100714 - Laurent_Lefort: O&M 2.0 definition

Observed Value (SensorML): A value describing a natural phenomenon, which may use one of a variety of scales including nominal, ordinal, ratio and interval. The term is used regardless of whether the value is due to an instrumental observation, a subjective assignment or some other method of estimation or assignment.

Orientation (SensorML): The rotational relationship of an object relative to a coordinate system. Typically expressed by relating the rotation of an object’s local coordinate system relative to an external reference coordinate system.

parameter: (O&M) If present, the parameter shall describe an arbitrary event-specific parameter. This might be an environmental parameter, an instrument setting or input, or an event-specific sampling parameter that is not tightly bound to either the feature-of-interest or to the observation procedure. To avoid ambiguity, there shall be no more than one parameter with the same name.

NOTE Parameters that are tightly bound to the procedure may be recorded as part of the procedure description.

In some contexts the procedure is a generic or standard procedure, rather than an event-specific process. In this context, parameters bound to the observation act, such as instrument settings, calibrations or inputs, local position, detection limits, asset identifier, operator, may augment the description of a standard procedure.

EXAMPLE A time sequence of observations of water quality in a well may be made at variable depths within the well. While these may be associated with specimens taken from the well at this depth as the features-of-interest, a more common approach is to identify the well itself as the feature-of-interest, and add a “samplingDepth” parameter to the observation

  • 20100714 - Laurent_Lefort: O&M 2.0 definition 6.2.2.5
  • 20100714 - Laurent_Lefort: this definition can be interpreted as attribute of event which cannot be placed elsewhere in the O&M model: there is a closed world assumption behind this definition which cannot be kept for the SSN ontology.
  • 20100714 - Laurent_Lefort: parameter is also defined in O&M 2.0 definition 8.2.2.2 in a different context

Phenomenon (SensorML), (O&M): concept that is a characteristic of one or more feature types, the value for which may be estimated by application of some procedure in an observation. Synonym for property-type in this specification. A physical property that can be observed and measured, such as temperature, gravity, chemical concentration, orientation, number-of-individuals. A characteristic of one or more feature types, the value for which must be estimated by application of some procedure in an observation.

  • 20091222 - Laurent_Lefort: VIM defines a quantity as a property of a phenomenon, body, or substance. SWE/SensorML's use of Phenomenon is confusing and should be avoided.

phenomenon time (O&M): The phenomenon time shall describe the time that the result applies to the property of the feature-of-interest. This is often the time of interaction by a sampling procedure or observation procedure with a real-world feature.

NOTE 1 The phenomenon time is the temporal parameter normally used in geospatial analysis of the result.

NOTE 2 If the observed property of an observation is ‘occurrence time’ then the result should be the same as the phenomenon time

  • 20100714 - Laurent_Lefort: O&M 2.0 definition 6.2.2.3

Platform tt>(O&M)</tt> : A common role for a spatial sampling feature is to host instruments or procedures deployed repetitively or permanently.

  • 20100714 - Laurent_Lefort: O&M 2.0 definition 9.2.1.4

Position (SensorML): The location and orientation of an object relative to a coordinate system. For body-based systems (in lieu of point-based systems) is typically expressed by relating the object’s local coordinate system to an external reference coordinate system. This definition is in contrast to some definitions (e.g. ISO 19107) which equate position to location.

procedure (O&M): method, algorithm or instrument, or system of these

  • 20091222 - Laurent_Lefort: VIM specifies that procedure has-part method

Process (SensorML): A process that takes one or more inputs, and based on parameters and methodologies, generates one or more outputs.

  • 20091222 - Laurent_Lefort: SensorML's definition of process corresponds to a computer science context only.

Process Method (SensorML): Definition of the behavior and interface of a Process. It can be stored in a library so that it can be reused by different Process instances (by using ‘xlink’ mechanism). It essentially describes the process interface and algorithm, and can point the user to existing implementations.

Process Chain (SensorML): Composite processing block consisting of interconnected sub-processes, which can in turn be Process Models or Process Chains. A process chain also includes possible data sources as well as connections that explicitly link input and output signals of sub-processes together. It also precisely defines its own inputs, outputs and parameters.

  • 20091222 - Laurent_Lefort: SensorML's definition of process chain corresponds to a computer science context but is confusing because of the use of signals (as opposed to data) which somewhat extend it to cover description of the "physics" of a measurement chain.

property: (O&M): facet or attribute of an object referenced by a name [ISO 19143:2010, definition 4.21]

  • 20100714 - Laurent_Lefort: (new) O&M 2.0 definition

property type (O&M): characteristic of a feature type

  • 20100714 - Laurent_Lefort: (new) O&M 2.0 definition

Reference Frame (SensorML): A coordinate system by which the position (location and orientation) of an object can be referenced.

Result (SensorML): an estimate of the value of some property generated by a known procedure

result quality (O&M): If present, the result quality shall describe the quality of the result. This instance-specific description complements the description of the observation procedure, which provides information concerning the quality of all observations using this procedure. Quality of a result may be assessed following the procedures in ISO 19114. Multiple measures may be provided (ISO/TS 19138:2006).

  • 20100714 - Laurent_Lefort: O&M 2.0 definition (6.2.2.6)

result time (O&M): The result time shall describe the time when the result became available, typically when the procedure associated with the observation was completed For some observations this is identical to the phenomenonTime. However, there are important cases where they differ.

EXAMPLE 1 Where a measurement is made on a specimen in a laboratory, the phenomenonTime is the time the specimen was retrieved from its host, while the resultTime is the time the laboratory procedure was applied.

EXAMPLE 2 The resultTime also supports disambiguation of repeat measurements made of the same property of a feature using the same procedure.

  • 20100714 - Laurent_Lefort: O&M 2.0 definition 6.2.2.3

observation result (O&M): estimate of the value of a property determined through a known observation procedure

  • 20100714 - Laurent_Lefort: O&M 2.0 definition

Sample (SensorML), (O&M): A subset of the physical entity on which an observation is made.

scale (O&M): a particular way of assigning numbers or symbols to measure something is called a scale of measurement SAR1995

  • 20091222 - Laurent_Lefort: Use the VIM terminology for units and quantities (or maybe QUOMOS-updated VIM )

Sensor (SensorML): An entity capable of observing a phenomenon and returning an observed value. In SensorML, modeled as a specific type of System representing a complete Sensor. This could be for example a complete airborne scanner which includes several Detectors (one for each band).

  • 20091222 - Laurent_Lefort: see the VIM definitions of system, sensor, detector, transducer

sensor (IEEE P1451): A transducer which converts a physical, biological, or chemical parameter into an electrical signal.

  • 20100201 - Laurent_Lefort: note the difference of scope with the SensorMl definition which covers all types of sensing systems.

Sensor Model (SensorML): In line with traditional definitions of the remote sensing community, a sensor model is a type of Location Model that allows one to georegister observations from a sensor (particularly remote sensors).

  • 20091222 - Laurent_Lefort: Have no clue what the "traditional definitions " refers to. Sounds like the sum of a measuerment model (or chain?) using one or several CRSs.

(Sensor) Platform (SensorML): An entity to which can be attached sensors or other platforms. A platform has an associated local coordinate frame that can be referenced to an external coordinate reference frame and to which the frames of attached sensors and platforms can be referenced.

smart actuator(IEEE P1451): An actuator version of a smart transducer.

smart sensor(IEEE P1451): A sensor version of a smart transducer.

smart transducer(IEEE P1451): A transducer that provides functions beyond those necessary for generating a correct representation of a sensed or controlled quantity. This functionality typically simplifies the integration of the transducer into applications in a networked environment.

  • 20100201 - Laurent_Lefort: another interesting difference: for IEEE 1451, basic sensors do not include all the additional capabilities required by a Sensor Network. Only "Smart" sensor do that.

System (SensorML): Composite model of a group or array of components, which can include detectors, actuators, or sub-systems. A System relates a Process Chain to the real world and therefore provides additional definitions regarding relative positions of its components and communication interfaces.

Transducer (SensorML): An entity that receives a signal as input and outputs a modified signal as output. Includes detectors, actuators, and filters.

  • 20100201 - Laurent_Lefort: Does not exactly correspond to the IEEE P1451 definition which is more general (see below)

Transducer (IEEE P1451): A device converting energy from one domain into another. The device may either be a sensor or an actuator.

  • 20100201 - Laurent_Lefort: IEEE P1451 implicitly targets control systems and not other types of systems.

valid time: (O&M): If present, the attribute validTime:TM_Period shall describe the time period during which the result is intended to be used.

NOTE This attribute is commonly required in forecasting applications.

  • 20100714 - Laurent_Lefort: O&M 2.0 definition 6.2.2.4

value (SensorML), (O&M): member of the value-space of a datatype. A value may use one of a variety of scales including nominal, ordinal, ratio and interval, spatial and temporal. Primitive datatypes may be combined to form aggregate datatypes with aggregate values, including vectors, tensors and images (ISO/IEC 11404).

  • 20091222 - Laurent_Lefort: thinks this definition of value is larger than the one used in VIM (would prefer to stick to VIM)
  • 20091222 - Laurent_Lefort: Value not defined in (ISO TC211)