Is Altitude a Relational Quality?

[cameronmore]

In discussions with @CarterBeauBenson and @johnbeve , I think 'Altitude' may be a bfo:RelationalQuality. Specifically, Altitude seems to be a relational quality between some point or site and another point or site near the surface of the earth.

The current definition is A Height that inheres in a Site that externally connects an Independent Continuant to either the surface of the Earth or the Earth's mean Sea Level. There are a few considerations about this definition:

1. Wouldn't it be more accurate to say that it inheres in a Fiat Line that connects two continuants, rather than a Site, since really altitude is measured as a straight line distance down from some entity?
2. Is it really inhering in the site (the middle thing between the points) or the two points in virtue of there being some imaginary line between them?
3. If it's really in virtue of this imaginary line, then we might consider the same pattern for Distance (not a CCO class currently)?

Height, and its super class One Dimensional Extent, are defined ultimately as A Size Quality that inheres in a bearer in virtue of the bearer's extension in one dimension, which seems not to be the case with altitude and distance? My height inheres in my extent in a certain spatial orientation--in my extent--while Altitude and distance are really inhering in the two things being compared, albeit with reference to some extent of a fiat line between them. Further, following the relational quality thread above, one could make the argument that Height and One Dimensional Extend also are relational qualities that inhere in points that are parts of some extended continuant.

I would propose that Distance be a subclass of Relational Quality, Altitude be a subclass of Relational Quality, and the other classes that represent one-dimensional extent remain where they are.

Practically speaking, I am not sure if this would require complete deprecation of the current class since all relational qualities are bfo:Qualities, and while making actual knowledge graphs, one could simple omit the 'other half' of what Altitude or Distance inheres in.

[cameronmore]

Proposed draft definitions:

Distance = A Relational Quality that inheres in two Independent Continuants that are not Spatial Regions in virtue of the extent of a Fiat Line that Connects them.

Altitude = A Distance that inheres in two Independent Continuants that are not Spatial Regions, one of which is at or near the surface of the Earth or the Earth's Mean Sea Level.

I can see a potential problem with this proposed definition of Distance if someone wants to model the distance between two cities on a road trip, or the distance between stops on a train track. Perhaps there is a class between these two such as Direct Distance:

Direct Distance = A Distance that inheres in two Independent Continuants that are not Spatial Regions in virtue of the extent of a straight Fiat Line that Connects them.

This, however, raises the issue of the curved nature of celestial bodies--the line between New York and London is not straight but it does appear to be on a sphere. Perhaps the 'straight' qualification should only be included in the definition of Altitude and we forget the idea of 'Direct Distance' (or add an annotation warning users of this qualification).

[swartik]

Regarding celestial bodies:

• The skos:definition of fiat line states it's one-dimensional.
• The skos:example annotation for fiat line includes the Equator and all lines of latitude and longitude.

My topology is very rusty. Is this a contradiction? If it isn't, great circle distances would seem acceptable.

Regarding the definition of Altitude, it needs to state that the Distance from the point at or near the Earth's surface to the other point is with respect to the z-axis, or words to that effect.

[cameronmore]

definitely agree about including a clause to the effect of 'a point directly overhead another point that is at or near the surface of the Earth.' @swartik

[mark-jensen]

@cameronmore Plenty to say about this. I will follow up with some direct feedback soon.

In meantime please look at CCO...669 'distance measurement information content entity'

Also, there are many kinds of altitudes. CCO should have general term for all of them. What you are defining, which is what the current term seems to be representing, is conflating true altitude and absolute altitude.

[CarterBeauBenson]

I just want to make minor amendments to the definitions:

Distance relational quality is a relational quality that inheres in x and y where x and y are fiat points and x is not identical to y. (this may only be a necessary condition, but not a sufficient. I cannot think of another quality that would inhere in two fiat points).

Edit:
Altitude relational quality is a distance relational quality there inheres in x and y where... Then the high level altitude definition becomes difficult because it seems like it would just be a disjunct of the differentia of its subclasses.

Altitude above ellipsoid is an altitude relational quality where x is a continuant part of Reference Earth Ellipsoid and y is continuant part of some continuant and not a spatial region located in the earth's atmosphere(?). (there is likely a more elegant way to specify that altitude has to do with being above the ellipsoid)

Mean Earth Ellipsoid is an instance of fiat surface that is prescribed by an estimate ICE that is the the mean curvature quality that inheres in the Earth.

Reference Earth Ellipsoid is an instance of a fiat surface that is prescribed by an estimate ICE of the Earth geoid.

Distance measurement is a measurement ICE of some distance.
Altitude measurement is a measurement of some Altitude

[cameronmore]

@mark-jensen I think we are in agreement, there should be a generic class for use across kinds of altitude. Distance Measurement ICE seems to reference Distance (by using a capital letter) which does not appear in the CCO.

[alanruttenberg]

In my ontology I have distance (as well as position) as relational. If you are fixing altitude you should not build in that it is an Earth altitude. Nor other such entities. There are altitudes relative to the moon or any other planetary body.

I'm not sure that height above ellipsoid should be a distinct quality. Measuring from the ellipsoid is one way of measuring height. There are others, from sea level as well.

I don't think of the altitude inhering in a fiat line. It inheres with the thing that is at the altitude and the planet. Or an ellipsoid, or a sphere in some cases. There are (historically) multiple and even WGS84 gets refined over time. A distance is between two things. A length is the sort of thing a line has. As far as vertical coordinates go, you can measure the distance to ellipsoid along a normal to the ellipsoid or in the direction of the center of mass of the Earth.

I have 'ellipsoid boundary' as a class. Definition: "a fiat surface that may be obtained from a sphere by deforming it by means of directional scalings in three perpendicular directions". A particular boundary would be related to Earth, for example, by using my relation 'is immaterial entity host' or an inverse. There are ICEs (transforms) that relate one ellipsoid to another. Many historically are defined by such.

If others are doing Geospatial stuff we should meet and discuss since I already have representations of coordinate systems and coordinates, and we should be aiming for interoperability. And I would love to review and compare.

[cameronmore]

1. I agree, altitude (the 'generic' kind) itself shouldn't be fixed or the earth.
2. I agree it inheres in the two things, not some fiat line, though it might be a good idea to include in the definition.
3. If altitude is a relational quality between two points or sites (or whatever we settle and agree on), one of which being a fiat surface, then why wouldn't other kinds of altitude by different relational qualities? An aircraft can have both an altitude above sea level and an altitude above the ellipsoid at the same time--that seems like two relational qualities with two fiat surfaces rather than two ways of measuring one fiat surface, right?
4. I am likely not doing anything as complex as your use case warrants, but I would be happy to connect offline if you reach out to my work email

[mark-jensen]

@cameronmore @alanruttenberg @CarterBeauBenson

To be clear, your proposal is this:

'ICE' is_about 'altitude relational quality'
'altitude relational quality' inheres_in 'entity 1' (eg, seal level)
'altitude relational quality' inheres_in 'entity 2' (eg, airplane)
'ICE' has_value "30,000 ft"

'altitude relational quality' is a species of 'distance relational quality'

Question:
Wouldn't it be the case that any extent (length, width, height, circumference, etc) also be a relational quality rather than a quality born singularly by an entity? If, not, what criteria differentiate the two approaches?
E.g., Is the height of Mt Everest represented differently than the elevation of a person standing on the top of it?
E.g., Is the length of a table represented differently than the distance between two knots on opposite sides of it?

[CarterBeauBenson]

@mark-jensen
This is an excellent question. I think I am amenable to an interpretation of height that is a relational quality also between two points. @johnbeve made a similar point in private conversation. I wonder if distance is between the two fiat points whereas length or height is of a fiat line or material entity (or something). I recognize that this is a drastic departure from the way these things are typically modelled.

[cameronmore]

@mark-jensen
Agree with @CarterBeauBenson . Just thinking through the possibilities, here's another distinction we could make: that length, height, width are all the extent of some thing and distance/altitude is the extent between two things. Admittedly though, this isn't even a consistent distinction in natural language (the 'width of a room' is, for example, the distance between the walls). Further, there are kinds of altitude (like Height Above Ellipsoid) that explicitly use the word height.

I think the models are so similar that we might just have to take a stance (keep as a quality or make relational quality), document the decision, and provide the design pattern.

[BrendaBraitling]

@mark-jensen My really quick response is... this... but I elaborate below....
The difference is the frame of reference and axis orientation of the length measurement between two points.

@cameronmore @CarterBeauBenson @johnbeve @alanruttenberg @swartik

APPLIED ONTOLOGY
Gentlemen, perhaps I can provide a pragmatic perspective... I deal with information systems and standards... military, civil code, health care, biology, physics, digital twins, geospatial systems, electron microscopes, telescopes, weather, manufacturing, simulations.... Just like those who want to connect up with this MLO...

SAMPLES OF EXTENSIONS
It may be that Common Core clarifies the difference between measuring and abstractions of how we do the measuring.... Perhaps there may need to be more than 500 extensions available for more technical and granular uses and maybe a dozen that need to be provided in the standard...

Four factors... that I notice...

1. Length is the measure and has units of some sort of scale,
2. Distance is abstract and can be discussed without applying an instance of scaled measurement,
3. Orientation is where we define an axis of orientation or a fiat reference feature (natural waist, mean sea level)
4. Cartesian coordinates set a unit measure in maths... and allows axis and vectors - An example of how scale and orientation can allow for 1D entities to inhabit additional dimensions and be able to handle a myriad of complex cases.

So, I see for your collective expertise in logical handling ...

• must be 1 Dimensional
• line segment
• 2 stated end points
• fiat end points
• this 1D construct can allow arc lengths and circumference to be described and not just straight line segments.

In my practitioner point of view... we need to satisfy these kinds of cases....

• Length is what we measure using some scale - as a distance between two designated points.
• Sometimes the the points are fiat and/or specifically defined points - one point being part of a plane, like mean sea level, measured precisely along a perpendicular path to the second point.
• Height, width and depth are each 1D measurements between specified points using a declared 3D axis of orientation and having well defined edges like a crate or a table - (perhaps a stone, but never a mountain...)
• Neck, sleeve, natural waist, inseam.... fiat, well described points to measure a specific arc length (circumference) or length between them.
• geospatial measurements are not just an oriented measurement, they are oriented to defined geospatial features

GEOSPATIAL - Cases of special orientations...
altitude as described is geospatial - one entity is the plane of mean sea level while the other is a point.
Interestingly - altimeters generally measure pressure to derive distance from mean sea level as a measure of length.

Regarding Mt Everest - it is not a discrete material entity like a human organism or a shipping crate.
However, it is geospatially oriented.
The human on top of the mountain or at the beach is still 72 inches height... not geospatial...
Ground Elevation is a point on the ground measured from the plane of mean sea level.

Geospatial measures will be interesting on different planets....
Perhaps we will use laser paths or beacons where we have no sea and no atmosphere...

The rest is for the LLM...
The applied ontology will provide semantic reasoning that works - even though humans will always be eccentric in their communications and practices..

blueprints having ... an Elevation View....
cloud heights... while aircraft fly at altitudes...
high-altitude climbing on Mountains ... having a particular minimum elevation...
and my favorite --the theodolite - which is about angles... and planes... but delivers results in 1D distances...

Hope this is helpful to your logical deliberations!
Brenda

[arazdow]

Jumping in, sorry if I’ve missed earlier posts - doesn’t “height” measure normal distance “above” a plane of reference (such as the Earth’s surface)? From: Carter-Beau Benson ***@***.***> Sent: Thursday, April 17, 2025 4:09 PM To: CommonCoreOntology/CommonCoreOntologies ***@***.***> Cc: Subscribed ***@***.***> Subject: Re: [CommonCoreOntology/CommonCoreOntologies] Is Altitude a Relational Quality? (Issue #641) @mark-jensen <https://github.com/mark-jensen> This is an excellent question. I think I am amenable to an interpretation of height that is a relational quality also between two points. @johnbeve <https://github.com/johnbeve> made a similar point in private conversation. I wonder if distance is between the two fiat points whereas length or height is of a fiat line or material entity (or something). I recognize that this is a drastic departure from the way these things are typically modelled. — Reply to this email directly, view it on GitHub <#641 (comment)> , or unsubscribe <https://github.com/notifications/unsubscribe-auth/AABY3JXSREP73TV2OCREHBD22AC57AVCNFSM6AAAAAB2MMTJOKVHI2DSMVQWIX3LMV43OSLTON2WKQ3PNVWWK3TUHMZDQMJTHEYTMMZXGQ> . You are receiving this because you are subscribed to this thread.Message ID: ***@***.***> CarterBeauBenson left a comment (CommonCoreOntology/CommonCoreOntologies#641) <#641 (comment)> @mark-jensen <https://github.com/mark-jensen> This is an excellent question. I think I am amenable to an interpretation of height that is a relational quality also between two points. @johnbeve <https://github.com/johnbeve> made a similar point in private conversation. I wonder if distance is between the two fiat points whereas length or height is of a fiat line or material entity (or something). I recognize that this is a drastic departure from the way these things are typically modelled. — Reply to this email directly, view it on GitHub <#641 (comment)> , or unsubscribe <https://github.com/notifications/unsubscribe-auth/AABY3JXSREP73TV2OCREHBD22AC57AVCNFSM6AAAAAB2MMTJOKVHI2DSMVQWIX3LMV43OSLTON2WKQ3PNVWWK3TUHMZDQMJTHEYTMMZXGQ> . You are receiving this because you are subscribed to this thread.Message ID: ***@***.***>

[arazdow]

Brenda, it may be worth considering NIST’s point of view in the SI Standard. They distinguish a fundamental physical quantity such as length or energy, from aliases like height or work which are members of their respective quantity categories (length and energy). But beyond being aliases, they also carry meaning external to their SI meaning. Work is energy expended by applying a force over a distance, but is energy, nonetheless. Length, width, height, diameter, are all lengths, but include semantics of related to the context of their application. Diameter is a length but wouldn’t be applied to a square. So, HEIGHT is in the quantity category of length, but how to describe its domain of application is what I guess is being debated here. Allen Razdow (inventor of Mathcad) From: Brenda Braitling MISM ***@***.***> Sent: Thursday, April 17, 2025 7:50 PM To: CommonCoreOntology/CommonCoreOntologies ***@***.***> Cc: Subscribed ***@***.***> Subject: Re: [CommonCoreOntology/CommonCoreOntologies] Is Altitude a Relational Quality? (Issue #641) @mark-jensen <https://github.com/mark-jensen> My really quick response is... this... but I elaborate below.... The difference is the frame of reference and axis orientation of the length measurement between two points. @cameronmore <https://github.com/cameronmore> @CarterBeauBenson <https://github.com/CarterBeauBenson> @johnbeve <https://github.com/johnbeve> @alanruttenberg <https://github.com/alanruttenberg> @swartik <https://github.com/swartik> APPLIED ONTOLOGY Gentlemen, perhaps I can provide a pragmatic perspective... I deal with information systems and standards... military, civil code, health care, biology, physics, digital twins, geospatial systems, electron microscopes, telescopes, weather, manufacturing, simulations.... Just like those who want to connect up with this MLO... SAMPLES OF EXTENSIONS It may be that Common Core clarifies the difference between measuring and abstractions of how we do the measuring.... Perhaps there may need to be more than 500 extensions available for more technical and granular uses and maybe a dozen that need to be provided in the standard... Four factors... that I notice... 1. Length is the measure and has units of some sort of scale, 2. Distance is abstract and can be discussed without applying an instance of scaled measurement, 3. Orientation is where we define an axis of orientation or a fiat reference feature (natural waist, mean sea level) 4. Cartesian coordinates set a unit measure in maths... and allows axis and vectors - An example of how scale and orientation can allow for 1D entities to inhabit additional dimensions and be able to handle a myriad of complex cases. So, I see for your collective expertise in logical handling ... * must be 1 Dimensional * line segment * 2 stated end points * fiat end points * this 1D construct can allow arc lengths and circumference to be described and not just straight line segments. In my practitioner point of view... we need to satisfy these kinds of cases.... * Length is what we measure using some scale - as a distance between two designated points. * Sometimes the the points are fiat and/or specifically defined points - one point being part of a plane, like mean sea level, measured precisely along a perpendicular path to the second point. * Height, width and depth are each 1D measurements between specified points using a declared 3D axis of orientation and having well defined edges like a crate or a table - (perhaps a stone, but never a mountain...) * Neck, sleeve, natural waist, inseam.... fiat, well described points to measure a specific arc length (circumference) or length between them. * geospatial measurements are not just an oriented measurement, they are oriented to defined geospatial features GEOSPATIAL - Cases of special orientations... altitude as described is geospatial - one entity is the plane of mean sea level while the other is a point. Interestingly - altimeters generally measure pressure to derive distance from mean sea level as a measure of length. Regarding Mt Everest - it is not a discrete material entity like a human organism or a shipping crate. However, it is geospatially oriented. The human on top of the mountain or at the beach is still 72 inches height... not geospatial... Ground Elevation is a point on the ground measured from the plane of mean sea level. Geospatial measures will be interesting on different planets.... Perhaps we will use laser paths or beacons where we have no sea and no atmosphere... The rest is for the LLM... The applied ontology will provide semantic reasoning that works - even though humans will always be eccentric in their communications and practices.. blueprints having ... an Elevation View.... cloud heights... while aircraft fly at altitudes... high-altitude climbing on Mountains ... having a particular minimum elevation... and my favorite --the theodolite - which is about angles... and planes... but delivers results in 1D distances... Hope this is helpful to your logical deliberations! Brenda — Reply to this email directly, view it on GitHub <#641 (comment)> , or unsubscribe <https://github.com/notifications/unsubscribe-auth/AABY3JVV5WDEQJHYFVTNF4322A43DAVCNFSM6AAAAAB2MMTJOKVHI2DSMVQWIX3LMV43OSLTON2WKQ3PNVWWK3TUHMZDQMJUGIYTKNBUG4> . You are receiving this because you are subscribed to this thread.Message ID: ***@***.***> BrendaBraitling left a comment (CommonCoreOntology/CommonCoreOntologies#641) <#641 (comment)> @mark-jensen <https://github.com/mark-jensen> My really quick response is... this... but I elaborate below.... The difference is the frame of reference and axis orientation of the length measurement between two points. @cameronmore <https://github.com/cameronmore> @CarterBeauBenson <https://github.com/CarterBeauBenson> @johnbeve <https://github.com/johnbeve> @alanruttenberg <https://github.com/alanruttenberg> @swartik <https://github.com/swartik> APPLIED ONTOLOGY Gentlemen, perhaps I can provide a pragmatic perspective... I deal with information systems and standards... military, civil code, health care, biology, physics, digital twins, geospatial systems, electron microscopes, telescopes, weather, manufacturing, simulations.... Just like those who want to connect up with this MLO... SAMPLES OF EXTENSIONS It may be that Common Core clarifies the difference between measuring and abstractions of how we do the measuring.... Perhaps there may need to be more than 500 extensions available for more technical and granular uses and maybe a dozen that need to be provided in the standard... Four factors... that I notice... 1. Length is the measure and has units of some sort of scale, 2. Distance is abstract and can be discussed without applying an instance of scaled measurement, 3. Orientation is where we define an axis of orientation or a fiat reference feature (natural waist, mean sea level) 4. Cartesian coordinates set a unit measure in maths... and allows axis and vectors - An example of how scale and orientation can allow for 1D entities to inhabit additional dimensions and be able to handle a myriad of complex cases. So, I see for your collective expertise in logical handling ... * must be 1 Dimensional * line segment * 2 stated end points * fiat end points * this 1D construct can allow arc lengths and circumference to be described and not just straight line segments. In my practitioner point of view... we need to satisfy these kinds of cases.... * Length is what we measure using some scale - as a distance between two designated points. * Sometimes the the points are fiat and/or specifically defined points - one point being part of a plane, like mean sea level, measured precisely along a perpendicular path to the second point. * Height, width and depth are each 1D measurements between specified points using a declared 3D axis of orientation and having well defined edges like a crate or a table - (perhaps a stone, but never a mountain...) * Neck, sleeve, natural waist, inseam.... fiat, well described points to measure a specific arc length (circumference) or length between them. * geospatial measurements are not just an oriented measurement, they are oriented to defined geospatial features GEOSPATIAL - Cases of special orientations... altitude as described is geospatial - one entity is the plane of mean sea level while the other is a point. Interestingly - altimeters generally measure pressure to derive distance from mean sea level as a measure of length. Regarding Mt Everest - it is not a discrete material entity like a human organism or a shipping crate. However, it is geospatially oriented. The human on top of the mountain or at the beach is still 72 inches height... not geospatial... Ground Elevation is a point on the ground measured from the plane of mean sea level. Geospatial measures will be interesting on different planets.... Perhaps we will use laser paths or beacons where we have no sea and no atmosphere... The rest is for the LLM... The applied ontology will provide semantic reasoning that works - even though humans will always be eccentric in their communications and practices.. blueprints having ... an Elevation View.... cloud heights... while aircraft fly at altitudes... high-altitude climbing on Mountains ... having a particular minimum elevation... and my favorite --the theodolite - which is about angles... and planes... but delivers results in 1D distances... Hope this is helpful to your logical deliberations! Brenda — Reply to this email directly, view it on GitHub <#641 (comment)> , or unsubscribe <https://github.com/notifications/unsubscribe-auth/AABY3JVV5WDEQJHYFVTNF4322A43DAVCNFSM6AAAAAB2MMTJOKVHI2DSMVQWIX3LMV43OSLTON2WKQ3PNVWWK3TUHMZDQMJUGIYTKNBUG4> . You are receiving this because you are subscribed to this thread.Message ID: ***@***.***>