Zero Dimensional Spatial Regions

[Jlbillig]

In reviewing Zero Dimensional Spatial Regions several issues present themselves. Some of these issues stem from improper labeling, categorically mislabeling, and as a consequence of not having defined classes. I will present an argument for each.

-Center Of Mass
Center of mass is listed as a ZDSR. I believe this is because the definition is "the point where the weighted position vectors of the distributed Mass of a Material Entity relative to this point sum to zero." While this is how we mathematically come to find a COM, it is not the COM itself. The COM of any material entity is closer to a quality. Every material entity bears a COM in virtue of existing and does not require any process to bear it. It is specifically dependent on the material entity which bears it. An entity's COM can change position from material changes, as well as the vectors that allow us to calculate it. An entity's COM not only change within the entity itself, but within spatial regions as a whole. ZDSR's are supposed to be static representation of a point in space time, and unlike the other subclasses of ZDSR, COM is the only one that does not track movement. COM belongs as a quality.

-Object Track Point/Ground Track Point
Object Track Point and Ground Track Points are mislabeled as ZDSRs, they are more apt as Fiat points. GTP are projections of an OTP onto an astronomical body which moves. This again ignores that ZDSR are meant to be absolute representations of a static point in space time. Planets rotate, change orbits, explode, etc. Every OTP has a GTP but not vice versa, because GTP are only the projection of an object whose track points were not located on the surface of their respective astronomical bodies (air or sea). Drawing the line between an OTP and GTP makes a one-dimensional spatial region so when an entity has both an OTP and GTP, it creates an ODSR, which is distinctly not a ZDSR.

-Vehicle Track Point
A vehicle is an object, capable of having OTP and GTP, there is nothing distinct enough about a vehicle to warrant its own class. If the idea is that vehicles have motion from a human agent such as driving, but objects like a tumbleweed do not realize their acts of motion through agency but by wind, it becomes more about how that motion is achieved rather than what track points are supposed to focus on- points of motion themselves. This is understandable because CCO does not want to use OWL reasoning due to its performance in large datasets and while this should be a defined class, it is not.

OTP and GTP are more geospatial positions. The problem with this is that there exists no appropriate ICE to describe them. In my experience with CCO, geocoordinates have been the latitude and longitude values of MICE, but this is incorrect. MICE as, "A Descriptive Information Content Entity that describes the extent, dimensions, quantity, or quality of an Entity relative to some standard." Does not accommodate for geocoordinates. Geocoordinates are the zero-dimensional intercession between a latitude and longitude. The definition uses "dimensions" and "extent" to describe what is being measured, but CCO does not include zero-dimensional extent because something that is zero dimensional has no extent. An ICE that can allow for this information would be something like Spatial Location Information Content Entity (SLICE). A SLICE is about some Geospatial Location and would be the proper container of latitude and longitude values.

[alanruttenberg]

Center of mass. Most suggestions have it as a fiat point. Fiat points, as continuants, can change in time. See #598. But related to this, in my ontology, I have position as a relational quality. For the center of mass it would inhere in the fiat point and Earth.

Object tracks: concur

Vehicle track point: No opinion. Will leave to other CCO developers.

Geospatial positions: Geospatial positions fit - they are fiat points. Coordinate systems describe or measure the fiat points. I would comment on the definition that being on the "non-information" side of the ontology geospatial positions should not be appealing to information artifacts in its definition.

It is intended that some geospatial coordinates fall under MICE, so this an issue with the definition. I suggest submitting a separate ticket pointing out that the definition needs adjustment to allow for coordinates. Note that not all such coordinates are MICE, however. For instance, a target position, or predicted position is not measured but designated or computed.

There has been a proposal for value specifications submitted to CCO which generalize to include measurements, predictions and measurements. Hopefully coming soon.