Comments please! Enter below or email me. Thanks. AnitaRichards - 04 Aug 2003

Many helpful comments received from Bob Hanisch and Tony Linde, gist of these entered on Monday 4 Aug - where the comment is just "Why do we need xxxYyy" I have added a further attempt at justification

This is based on our discussions plus the latest version of Bob Hansich et al.'s Resource and Service Metadata v0.8 (RSMv0.8).

RSMv0.8 notes some quantities as optional, others not stated. I have made most things optional because as Elizabeth pointed out the present distribution of elements between Curation, Content etc. means that non-dataSet resources would have an awful lot of NaN's etc. otherwise. However in the long run a better solution would be to have a few more top-level sections applicable to specific kinds of resources (e.g. a more inclusive Coverage section) and make more things within each section compulsory. This will possibly come out of Tony and Ray's debate... see Elizabeth's added elements below.

See RSMv0.8 for descriptions of all elements not given here, conventions in measurement etc. I can add these here if people want - let me know.

These pieces of shorthand are slightly simplified versions of what is in the schemas in order to show the intentions.

N/A is shorthand for allowed values "unknown", "notApplicable", "notAvailable"
myString is "" or N/A
myFloat is xs:float or myString.
Unless otherwise stated element types are either xs:string or myFloat
There are some conditional restrictions which I think are desirable which I haven't figured out how to express:

• If a spectral bandpass is given, e.g. B or L, then the waveband and limits or a central value in metres must also be given
• If the flux density units anywhere are given in mag, they must also be given in Jy Or should it be strictly Jy only? Opinions please.

In addition some elments can at present only occur once, we can increase their occurrence if we find a need and can handle it (e.g. spatial coverage region).

Top-level section
Required element
Unit All units can be left blank or have the specfied value
Suggested content elements added by ElizabethAuden
Other comments followed by contributor's name

Optional element
Comment about restricted type or values
!!! Element changed from RSMv0.8. (Minor changes in units/types are not shown, nor where a sub-element is added to enable a list to be restricted until we link to the relevant namespace)

---

The Schemas

identity

• title
• shortName 2 - 16 characters
• identifier URI

curation

• publisher
• publisherID URI
• creator
• creatorLogo URI
• subject
  • subjectKeyword From IAU Thesaurus probably more practical to use Vizier keywords to start with AnitaRichards - 06 Aug 2003 </font
• description
  • abstract CDATA Note that "quotation marks" cannot be included
  • README !!! URI Link to list of column headings with native units and UCDs if available
• contributor
• date date as per ISO8601
• version
• referenceURL
• source
• contact
  • name
  • email
• dataSize !!!
  • byteSize unitByteSize=" MB "
  • nPixels Total no. pixels or info units (X*Y; U*V*W*S etc) in a single image or other data unit e.g. single FITS file in a dataSet - if too large Registry may need to take some action like calling cutout server. Is this useful? Need a proper sky coverage service (Bob Hanisch)
  • nRows
  • nCols This should be nRecords for consistency - if used at all. I feel in some cases it might be useful to seach data sets in order of size, hence nRows and nCols - opinions please.

content

• contentLevel Select from general, elementaryEducation, middleSchoolEducation, secondaryEducation, communityCollege, university, research, amateur, informalEducation, N/A, ""
• rights Select from public, proprietary, mixed
• resourceType Select from archive, bibliography, catalogue, journal, library, simulation, survey, education, outreach, epoResource, animation, artwork, background, basicData, historical, photographic, press, organisation, project, integrated, nameresolver, community, mySpace
• format Select from application/fits, text/plain, text/html, text/xml, votable, image/gif, image/jpg, image/png, other, N/A (eventually any MIME type as per http://www.iana.org/assignments/media-types plus other formats as needed) (!!! VOTable included explicitly)
• resourceContent Select from datasetContent, communityContent, mySpaceContent
  • datasetContent
    • ucdList
      • ucd !!! Taken from CDS list and Vizier entries at present We are likely to be linking to data and services provided via CDS, UCDs are convenient search handles. For non-CDS data, we could either use the UCD-allocating tool or just omit this element. Eventually there will be superior UCD-type terms, a namespace for the IAU thesaurus etc. but UCDs are immediately usable - may already be a namespace?
    • coverage
      • coverageSpatial !!! Circle, Constraint and Convex omitted as they appear to be covered by other types Actually I should use/reference the definitions in the schema space-time coordinates (stc) schema at the bottom of the IVOA registry WP03 page AnitaRichards - 01 Aug 2003
        • regionSpatial
          • ellipse
            • cframe See main entry for cframeType; NB this is not necessarily the same type
              • cframeType
            • coordinatePair unitAngle=" deg " Centre of ellipse
              • coordinate
              • coordinate
            • ellipseParams unitAngle=" deg " Semi-major and -minor axes and position angle
              • coordinate
              • coordinate
              • coordinate
          • polygon
            • cframe See main entry for cframeType; NB this is not necessarily the same type
              • cframeType
            • coordinatePair unitAngle=" deg " Vertex
              • coordinate
              • coordinate
            • coordinatePair unitAngle=" deg " Vertex
              • coordinate
              • coordinate
            • coordinatePair unitAngle=" deg " Vertex
              • coordinate
              • coordinate
          • sector
            • cframe See main entry for cframeType; NB this is not necessarily the same type
              • cframeType
            • coordinatePair unitAngle=" deg " Origin
              • coordinate
              • coordinate
            • coordinatePair unitAngle=" deg " Two position angles
              • coordinate
              • coordinate
          • healpix !!! Simple system for indexing the sky, inclusion due to feedback from CMB astronomers HEALPIX Is this necessary? If so would HTM be better? See Indexing the Sky for a comparison.
            • cframe See main entry for cframeType; NB this is not necessarily the same type
              • cframeType
            • healpixNo In range [1-12], could use finer resolution
        • cframe
          • cframeType Select from ICRS, FK5, FK4, GAL, SGAL, N/A, ""
      • regionOfRegard unitAngle=" deg "
      • coverageSpectral
        • coverageSpectralRegion !!! Wrapper element which can be repeated as many times as there are wavebands, to allow ambiguous bandpass names to be associated with the correct waveband
          • coverageSpectralWaveband select from radio, mmWave, infrared, optical, uv, euv, xRay, gammaRay, N/A, "" (!!! mmWave is added)
          • coverageSpectralBandpass
        • coverageSpectralWavelengthRange unitSpectral=" metre or meter "
          • coverageSpectralCentralWavelength
          • coverageSpectralWavelengthShort
          • coverageSpectralWavelengthLong
      • coverageTemporal
        • coverageTemporalStartTime dateTime as per ISO8061 or myString
        • coverageTemporalStopTime dateTime as per ISO8061 or myString
      • coverageDepth fluxDensityUnit=" Jy or mag " unitArea=" object or deg+2 " Or should it be strictly Jy only? Opinions please.
      • coverageObjectDensity unitSpatialDensity=" deg-2 "
      • coverageObjectCount
      • coverageSkyFraction in range ]0-1] The IVOA stc schema uses fill factor which sounds much better; do we want this per spatialRegion, per sky/sphere, or even also per wavelength interval etc? AnitaRichards - 01 Aug 2003
  • • resolution
      • resolutionSpatial unitAngle=" deg "
      • resolutionSpectral unitSpectralResolution=" inverseFraction "
      • resolutionTemporal duration in sec or ""
    • dataQuality !!! Will change these to uncertaintyPhotometric/Spatial/Spectral/Astrometric at suggestion of Bob Hanisch
      • photometryError unitFluxDensity=" Jy or mag " unitArea=" object or deg+2 " Or should it be strictly Jy only? Opinions please.
      • astrometryError unitAngle=" deg "
      • timingError duration in sec or ""
    • facility
    • instrument
  • mySpaceContent
    • status suggest statusType to avoid confusion AnitaRichards - 07 Aug 2003
      • status
      • details
      • currentDate
    • dataItemRecords suggest dataItem to avoid confusion AnitaRichards - 07 Aug 2003
      • dataItemRecord
        • dataItemName
        • dataItemID
        • ownerID
        • creationDate
        • expiryDate
        • size
        • type
        • permissionsMask
        • dataHolderURI
  • communityContent
    • mySpaceLocation

  serviceMetadataConcept

  • interfaceMetadata
    • serviceInterfaceUrl
    • serviceBaseUrl
    • serviceHttpResults
  • capabilitiesMetadata
    • serviceStandardUri
    • serviceStandardUrl
    • serviceRestriction
      • serviceRestrictionSpatial unitAngle=" deg "
        • serviceMSR In range ]0-180]<font="purple">serviceMaxSearchRadius (Bob Hanisch)
        • serviceMaxImageSize !!! In range ]0-360]
      • serviceMaxNrows !!!<font="purple">serviceMaxReturnRecords (Bob Hanisch)

  -- AnitaRichards - 31 Jul 2003

  -- ElizabethAuden - 31 Jul 2003 (stuff in purple) TonyLinde has pointed out that most? of Elizabeth's suggestions for separate sections for non-data-set entries may be covered by the proposals he is thrashing out with Ray Plante et al.

  -- AnitaRichards - 01 Aug 2003 Use of colour - I (and Elizabeth) have tried to use standard dark colours and a change of font for the most significant differences so that I hope the document is still readable even if the colours do not appear as intended, but please let me know if it causes problems.

  -- ElizabethAuden - 31 Jul 2003 - added new elements for resourceContentType and did some slight rearranging.

  -- AnitaRichards - 07 Aug 2003 Started to impliment linking to namespaces. Some suggestions on more human-friendly element names. Also, I will create 'container' elements for those elements which can be lists, where this will aid human maintenance.

  -- ElizabethAuden - 08 Aug 2003 - added some purple thoughts regarding serviceRestriction elements. Please see latest version of the registry XML file, "registry_v1_1.xml", attached to RegistryIt03Metadata.