DGGS/Terms/pt

From https://docs.ogc.org/as/20-040r3/20-040r3.html#toc11

This document uses the terms defined in Sub-clause 5.3 of OGC 06-121r9, which is based on the ISO/IEC Directives, Part 2, Rules for the structure and drafting of International Standards. In particular, the word “shall” (not “must”) is the verb form used to indicate a requirement to be strictly followed to conform to this standard.

4.1. boundary

set that represents the limit of an entity

4.2. cell

<DGGS> spatial, spatio-temporal or temporal unit of geometry with dimension greater than 0, associated with a zone (Clause 4.52)

4.3. cell refinement

<DGGS> process of subdividing parent cells (Clause 4.33) into descendant child cells (Clause 4.4) using a specified refinement ratio (Clause 4.38) and suite of refinement strategies

4.4. child cell

<DGGS> immediate descendant of a parent cell (Clause 4.33)

4.5. class

description of a set of objects that share the same attributes, operations, methods, relationships, and semantics

Note 1 to entry: A class may use a set of interfaces to specify collections of operations it provides to its environment. The term was first used in this way in the general theory of object-oriented programming, and later adopted for use in this same sense in UML.

4.6. compound coordinate reference system

coordinate reference system (Clause 4.7) using at least two independent coordinate reference systems

4.7. coordinate reference system

coordinate system that is related to an object by a datum (Clause 4.10)

4.8. coordinate system

set of mathematical rules for specifying how coordinates are to be assigned to points

4.9. data type

specification of a value (Clause 4.49) domain with operations allowed on values in this domain

4.10. datum

parameter or set of parameters that realize the positions of the origin, the scale, and the orientation of a coordinate system (Clause 4.8)

4.11. datum ensemble

group of multiple realizations of the same terrestrial or vertical reference system that, for approximate spatial referencing purposes, are not significantly different

4.12. discrete global grid

<DGGS> set of cells (Clause 4.2) at the same refinement level (Clause 4.37), that uniquely and completely cover a globe (Clause 4.24)

4.14. duration

non-negative quantity of time equal to the difference between the final and initial instants (Clause 4.29) of a time interval (Clause 4.30)

4.15. dynamic coordinate reference system

coordinate reference system (Clause 4.7) that has a dynamic reference frame (Clause 4.16)

4.16. dynamic reference frame

reference frame (Clause 4.10) in which the defining parameters include time evolution

4.17. error budget

<metric> statement of or methodology for describing the nature and magnitude of the errors which affect the results of a calculation

[SOURCE: ISO 19107:2019, Clause 3.35, modified — Note 1 to entry has been removed] 4.18. feature

abstraction of real-world phenomena

Note 1 to entry: A feature can occur as a type or an instance. In this document, feature instance is meant unless otherwise specified.

[SOURCE: ISO 19101-1:2014, Clause 4.1.11, modified — Note 1 to entry has been added from ISO 19156:2011, Clause 4.6, and modified] 4.19. feature type

class (Clause 4.5) of features (Clause 4.18) having common characteristics

[SOURCE: ISO 19156:2011, Clause 4.7] 4.20. geodetic coordinate reference system

three-dimensional coordinate reference system (Clause 4.7) based on a geodetic reference frame and having either a three-dimensional Cartesian or a spherical coordinate system

Note 1 to entry: In this document a CRS based on a geodetic reference frame and having an ellipsoidal coordinate system is geographic.

[SOURCE: ISO 19111:2019, Clause 3.1.31] 4.21. geographic coordinate reference system

coordinate reference system (Clause 4.7) that has a geodetic reference frame and an ellipsoidal coordinate system

[SOURCE: ISO 19111:2019, Clause 3.1.35] 4.22. geographic identifier

spatial reference (Clause 4.41) in the form of a label or code that identifies a location (Clause 4.31)

Example

“Spain” is an example of a label (country name); “SW1P 3AD” is an example of a code (postcode).

[SOURCE: ISO 19112:2019, Clause 3.1.2] 4.23. geometric primitive

geometric object representing a single, connected, homogeneous (isotropic) element of space

Note 1 to entry: Geometric primitives are non-decomposed objects that present information about geometric configuration. They include points, curves, surfaces, and solids. Many geometric objects behave like primitives (supporting the same interfaces defined for geometric primitives) but are actually composites composed of some number of other primitives. General collections may be aggregates and incapable of acting like a primitive (such as the lines of a complex network, which is not connected and thus incapable of being traceable as a single line). By this definition, a geometric primitive is topological open, since the boundary (Clause 4.1) points are not isotropic to the interior points. Geometry is assumed to be closed. For points, the boundary is empty.

[SOURCE: ISO 19107:2019, Clause 3.50] 4.24. globe

<DGGS> region of space-time enclosing a celestial body

Note 1 to entry: In this document globe is used in its most general form to refer to any celestial body or region of space-time enclosing a celestial body that may be referenced by a DGGS (Clause 4.13). When a specific body, such as the Earth is referred to, an explicit term is used. 4.25. grid

network composed of two or more sets of curves in which the members of each set intersect the members of the other sets in an algorithmic way

Note 1 to entry: The curves partition a space into grid cells.

[SOURCE: ISO 19123:2005, Clause 4.1.23] 4.26. hierarchy

<DGGS> organization and ranking of successive levels of cell refinement (Clause 4.3) of discrete global grids (Clause 4.12) 4.27. initial discrete global grid

<DGGS> discrete global grid tessellation created by circumscribing a defined path along the chosen surface model of the Earth between the vertices of the scaled base unit polyhedron 4.28. interoperability

capability to communicate, execute programmes, or transfer data among various functional units in a manner that requires the user to have little or no knowledge of the unique characteristics of those units

Note 1 to entry: in this document interoperability specifically refers to functions that initiate and process transfers of data from a DGGS (Clause 4.13).

[SOURCE: ISO/IEC 2382:2015, Clause 2121317, modified — The original domain and Notes to Entry have been deleted. A Note 1 to entry has been added.] 4.29. instant

<DGGS> temporal geometry primitive representing a point in time

Note 1 to entry: On temporal coordinate systems (Clause 4.46) as specified in ISO 19107:2019, the temporal geometric primitives (Clause 4.23) instant and interval (Clause 4.30) are the equivalent of points and lines as specified in ISO 19107:2019. 4.30. interval

<DGGS> temporal geometry primitive representing a line in time

Note 1 to entry: On temporal coordinate systems (Clause 4.46) as specified in (ISO 19107:2019), the temporal geometric primitives (Clause 4.23) instant (Clause 4.29) and interval are the equivalent of points and lines as specified in ISO 19107:2019. 4.31. location

particular place or position

Note 1 to entry: A location identifies a geographic place.

Note 2 to entry: In the context of DGGS (Clause 4.13), locations have dimension greater than one, and so are not points.

Example

“Madrid”, “SW1P 3AD”.

[SOURCE: ISO 19112:2019, Clause 3.1.3, modified — Note two has been added and an additional example provided] 4.32. observation

act of measuring or otherwise determining the value (Clause 4.49) of a property

[SOURCE: ISO 19156:2011, Clause 4.11] 4.33. parent cell

<DGGS> cell (Clause 4.2) in a higher refinement level of discrete global grid with immediate descendants

Note 1 to entry: parent cells either overlap or contain their child cells (Clause 4.4). 4.34. period

<DGGS> particular era or span of time

Note 1 to entry: Periods are intervals (Clause 4.30) named with a period identifier (Clause 4.35) 4.35. period identifier

<DGGS> temporal reference in the form of a label or code that identifies a period (Clause 4.34)

Note 1 to entry: Period identifiers are the temporal equivalent of geographic identifiers (Clause 4.22) as specified in ISO 19112:2019 4.36. quantization

<DGGS> function assigning data from external sources to cell values 4.37. refinement level

<DGGS> numerical order of a discrete global grid (Clause 4.12) in the tessellation sequence

Note 1 to entry: The tessellation with the smallest number of cells has a refinement level = 0. 4.38. refinement ratio

<DGGS> ratio of the number of child cells (Clause 4.4) to parent cells (Clause 4.33)

Note 1 to entry: A positive integer ratio n refinement of DGGS (Clause 4.13) parent cells yield n times as many child cells as parent cells.

Note 2 to entry: For a two-dimensional DGGS (as defined for EAERS in this document) this is the surface area ratio.

Note 3 to entry: In DGGS literature [2] the term aperture has been used instead of refinement ratio. Refinement ratio is preferred because it is clearer in meaning to audiences outside the early DGGS community. 4.39. sibling cell

<DGGS> cell (Clause 4.2) in a discrete global grid with the same parent cell (Clause 4.33)

Note 1 to entry: all the child cells (Clause 4.4) of a parent cell are each-others’ sibling cells. 4.40. simple

<topology, geometry> homogeneous (all points have isomorphic neighbourhoods) and with a simple boundary (Clause 4.1)

Note 1 to entry: The interior is everywhere locally isomorphic to an open disc in a Euclidean coordinate space of the appropriate dimension Dn = {P|‖P‖ < 1.0}. The boundary is a dimension one smaller. This essentially means that the object does not intersect nor touch itself. Generally used for a curve that does not cross not touch itself with the possible exception of boundary points. Simple closed curves are isomorphic to a circle.

[SOURCE: ISO 19107:2019, Clause 3.84] 4.41. spatial reference

description of position in the real world

Note 1 to entry: This may take the form of a label, code or coordinate tuple.

[SOURCE: ISO 19111:2019, Clause 3.1.56] 4.42. spatio-temporal reference

system for identifying position in the real world that may include time

Note 1 to entry: This may take the form of a label, code or coordinate tuple. 4.43. spatio-temporal coordinate reference system

compound coordinate reference system (Clause 4.6) in which one constituent coordinate reference system (Clause 4.7) is a spatial coordinate reference system and one is a temporal coordinate reference system (Clause 4.47)

[SOURCE: ISO 19111:2019, Clause 3.1.59] 4.44. static coordinate reference system

coordinate reference system (Clause 4.7) that has a static reference frame (Clause 4.45)

Note 1 to entry: Coordinates of points on or near the crust of the Earth that are referenced to a dynamic coordinate reference system do not change with time.

Note 2 to entry: Metadata for a dataset referenced to a static coordinate reference system does not require coordinate epoch information.

[SOURCE: ISO 19111:2019, Clause 3.1.61] 4.45. static reference frame

reference frame (Clause 4.10) in which the defining parameters exclude time evolution

[SOURCE: ISO 19111:2019, Clause 3.1.62] 4.46. temporal coordinate system

<geodesy> one-dimensional coordinate system where the axis is time

[SOURCE: ISO 19111:2019, Clause 3.1.64] 4.47. temporal coordinate reference system

coordinate reference system (Clause 4.7) based on a temporal datum

[SOURCE: ISO 19111:2019, Clause 3.1.63] 4.48. tessellation

partitioning of a space into a set of conterminous subspaces having the same dimension as the space being partitioned