WD-Ontology
Ed Shaya
eshaya at umd.edu
Fri Feb 23 08:36:39 PST 2007
Tony Linde wrote:
>> ordinarily one would include them. For instance, what if it
>> is like a
>> cataclysmicVariable but not quite a LateType star.
>
> Is this not where relations come into play: you could define relations such
> as 'like a' and 'not quite a' and then, depending on what you want to do,
> manipulate the objects and relations in your code.
Yes, that would work. You could allow AstroObject to have a property
"likeA" or "nearly" which would allow one to toss objects into an
anonymous class of (F-star, nearly, CataclysmicVariable). I guess this
is better because you don't create as many named classes, but it has
basically the same functionally as a NearlyCataclysmicVariable. If
later on we wish to include F-stars as CVs, it would be easy to refactor
the ontology.
>> whether or not to use strictly observational qualities or interpreted
>> qualities. As in, what if it erupts and has emissions like a
>
> And this is where the uniqueness of astronomy comes into play and we start
> to build intelligent *astronomy* applications rather than generic
> information handling apps.
Agreed. Although I don't think that astronomy is somehow unique. Other
fields could benefit from the same thing. But, I agree with the gist
here that one can create very interesting applications, like one that
automatically classifies objects by observational quantities and then
attaches physical attributes/interpretations into what the objects are.
So, is everyone fine with the set of definitions that I put forth?
Speak now, because the next step would be to rephrase these into OWL
triples and make them part of the class' Necessary and Sufficient
statements. For example, if one claims an object is a GalaxyCluster,
then it would Necessarily be a virialized system because that is in the
definition.
Ed
>
> T.
>
>> -----Original Message-----
>> From: owner-semantics at eso.org
>> [mailto:owner-semantics at eso.org] On Behalf Of Ed Shaya
>> Sent: 21 February 2007 20:15
>> To: Andrea Preite Martinez
>> Cc: semantics at ivoa.net
>> Subject: Re: WD-Ontology
>>
>>
>>
>> Andrea Preite Martinez wrote:
>>> A Working Draft on
>>>
>>> Ontology of Astronomical Object Types, version 1.0
>>>
>>> has been uploaded in the Document section of IVOA
>>> http://ivoa.net/Documents/latest/AstrObjectOntology.html
>>>
>>> and in the Semantics WG twiki page
>>> http://www.ivoa.net/twiki/bin/view/IVOA/IvoaSemantics .
>>>
>>> In this page you can also find the ontology file (.owl) that can be
>>> explored/edited with the protégé browser/editor
>>> http://protege.stanford.edu/overview/protege-owl.html .
>>>
>>> The document and the Ontology are open to discussion and
>> contributions.
>>> Note that the ontology is made of "defined" concepts, and
>> only a fraction
>>> of them has been defined, for the moment only in terms of
>> components and/or
>>> morphology and/or processes.
>>> Indeed, there are still 87 astronomical concepts that are
>> missing an
>>> NS-condition (Necessary&Sufficient)
>>>
>>> I then ask for the contribution of the members of the WG and of the
>>> scientific
>>> community to help finding the necessary and/or sufficient
>> conditions to
>>> define the concepts.
>>> What is needed is a complete but concise description in
>> plain text of
>>> the concepts in terms of components/ morphology / physical
>> processes /
>>> observational properties and/or ...
>>>
>>> An example:
>>> CataclysmicVariable: close binary, components WD/subGiant
>> and LateType
>>> Star,
>>> variability due to thermonuclear processes...
>>>
>>> The concepts without NS-conditions (but sometimes already
>> with N or S
>>> conditions) are the following:
>> There are dangers in defining the necessary and sufficient
>> conditions,
>> particularly if one requires too many necessaries. You can
>> end up with
>> things that are not in any class although they are so close
>> to one that
>> ordinarily one would include them. For instance, what if it
>> is like a
>> cataclysmicVariable but not quite a LateType star. One also run into
>> whether or not to use strictly observational qualities or interpreted
>> qualities. As in, what if it erupts and has emissions like a
>> cataclysmic variable but it is too far away to discern the individual
>> components? Can you still call it a CV?
>>
>> On the other hand, if we don't make clear and distinct boundaries you
>> are left with a system that is too fuzzy to do any good.
>>
>> Having noted these difficulties, in the grand tradition of
>> semantics, we
>> simply push forward and appreciate that we can always pull
>> back on some
>> of these NS qualities or define both strict and loose
>> versions of each
>> class, as in StandardCalaclysmicVariable/TentativeCataclysmicVariable.
>>> AssociationOfStars - alias (equivalent class) StellarAssociation
>> Loose concentration of young stars (how loose? 1-100 per
>> cubic pc?), but
>> may contain 1 or more StellarClusters within it.
>> subclasses -
>> OB-Association - association with many O and B stars
>> (massive stars)
>> R-Association - contains medium mass stars with
>> reflection nebulae
>> T-Association - contains only low mass stars including
>> some T-Tauri stars
>>
>>> ClusterOfGalaxies - alias GalaxyCluster
>> Observationally - a region with a concentration of galaxies several
>> times the neighboring background density with similar galaxy
>> redshifts.
>> Theoretically - a collapsed and virialized system of galaxies
>> subclasses
>> AbellCluster - there are two definitions here
>> a) A cluster in the Abell Catalog
>> b) A cluster with the criteria given by Abell
>> for his catalog
>> Perhaps a) should be called an AbellCatalogCluster
>>
>>> SuperClusterOfGalaxies
>> A 3-d region of contiguous overdensity on Mpc scales.
>> Usually these
>> contain several clusters, but this should not be the
>> definition becuase
>> a) the Local Supercluster contains only 1 cluster b) if one found a
>> large contiguous overdensity without a cluster you probably
>> would still
>> want to classify it as a supercluster.
>>
>>> ClusterOfStars - alias StarCluster.
>> Observational - A tight system of stars with less than 10^9 stars.
>> Theoretical - A system of stars formed out of a single cloud
>> of gas and
>> with less mass than a galaxy (that is, .
>>
>>> GlobularCluster -
>> A roughly spherical ClusterOfStars with 10^4 - 10^9 stars and with an
>> orbit that takes it out of the plane of its parent galaxy.
>> [Normally the definition would include the idea that it is
>> composed of
>> old stars, but blue globular clusters in N1375 and other
>> galaxies show
>> that there are exceptions. Also, when globular clusters were
>> young they
>> had young stars and they were still globular clusters.]
>>
>>> OpenCluster - alias GalacticCluster
>> ClusterOfStars with young stars and with center of mass orbit
>> that stays
>> in the plane.
>>
>>> GalaxiesGroup
>> This should be GalaxyGroup - alias GroupOfGalaxies.
>> A system with on the order of 10 galaxies separated by 10-100 galaxy
>> diameters [Hopkins, J. 1976 Glossary of Astronomy and Astrophysics]
>>
>> I stop here to rest and wait for comments.
>> Ed
>>> Galaxy
>>> ActiveGalaxyNucleus
>>> Blazar
>>> BLLacObject
>>> OpticallyViolentlyVariableObject
>>> LINERTypeActiveGalaxyNucleus
>>> SeyfertGalaxy
>>> Seyfert1Galaxy
>>> Seyfert2Galaxy
>>> BlueCompactGalaxy
>>> EmissionLineGalaxy
>>> HighRedshiftGalaxy
>>> HIIGalaxy
>>> LowSurfaceBrightnessGalaxy
>>> QuasiStellarObject
>>> StarburstGalaxy
>>> SpectroscopicBinary
>>> XRayBinary
>>> InterStellarMedium
>>> EmissionNebula
>>> HIRegion
>>> HIRegionCold
>>> HIRegionWarm
>>> MolecularCloud
>>> BokGlobule
>>> DarkCloud
>>> ReflexionNebula
>>> StellarObject
>>> BrownDwarf
>>> Star
>>> PostAsymptoticGiantBranchStar
>>> RedGiant
>>> AsymptoticGiantBranchStar
>>> CarbonStar
>>> OHIREnvelopeTypeStar
>>> STypeStar
>>> RVTauri
>>> PeculiarStar
>>> CHEnvelopeTypeStar
>>> BeStar
>>> WolfRayetStar
>>> HorizontalBranchStar
>>> StellarRemnant
>>> NeutronStar
>>> Pulsar
>>> AccretionPoweredPulsar
>>> Magnetar
>>> RotationPoweredPulsar
>>> StellarBlackHole
>>> WhiteDwarf
>>> YoungStellarObject
>>> PreMainSequenceStar
>>> HerbigHaro
>>> TTauri
>>> ClassicalTTauri
>>> WeakLineTTauri
>>> ProtoStar
>>> SubStellarObject
>>> BrownDwarf
>>> NonStellarBody
>>> Asteroid
>>> Comet
>>> Planet
>>> CataclysmicVariable
>>> DQHerCataclysmicVariable
>>> DwarfNova
>>> Nova
>>> NovaLikeObject
>>> RapidIrregularVariableStar
>>> IrregularVariableStar
>>> RapidIrregularVariableStar
>>> BetaCepheid
>>> LTypeIrregularStar
>>> MiraCeti
>>> SemiRegularPulsatingStar
>>> RRLyrae
>>> WVir
>>> BYDraconis
>>> EllipsoidalVariableStar
>>> SymbioticStar
>>>
>>>
>>> P.S.:
>>> I think we can envisage a half-session in the spring IVOA
>> meeting in
>>> Beijin dedicated to the ontology and its applications.
>>>
>>> Andrea
>>>
>>>
>> ==============================================================
>> =====================
>>> Andrea Preite Martinez
>>> andrea.preitemartinez at iasf-roma.inaf.it
>>> IASF Tel.IASF:+39.06.4993.4641
>>> Via del Fosso del Cavaliere 100 Tel.CDS :+33.3.90242452
>>> I-00133 Roma Cell.1 :+39.320.43.15.383
>>> Cell.2 :+39.
>>>
>> ==============================================================
>> =====================
>>>
>>>
>>>
>
>
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