Title by pengxiang

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									Report on Progress
                            Overview
• First cut gazetteer database built
• Basic working demonstrator built
   – simple interface for reference use
   – basic machine2machine protocols adopted
• Servicing Go-Geo!
• Adaptation of ADL Feature Type Thesaurus
   (see separate handout)

• Outreach and stakeholder engagement underway
      geoXwalk - High Level Architecture

            (human interaction)
                                           (machine2machine interaction)
   Web client

                                                                       Information
                                                                          server
Request via protocol                            Request via protocol
  (ADL, OGC, Z39.50)                                  (ADL, OGC, Z39.50)

                            The geoXwalk
                               Server
                          (Spatially enabled RDBMs)
                Gazetteer Database
• Built on ADL Content Standard
• Currently seeded with:
   – OS 1:50,000 digital Gazetteer
   – digital boundary data from UKBORDERS
   – data sourced from other OS products - Strategi, Meridian,
     1:250,000 gazetteer
   – starting to add 3rd party data including Getty
• Accuracy enhanced and metadata support
• Current coverage:
   – Geographical - GB
   – Thematic - see below
     ADL Gazetteer Content Standard
Geographic Feature ID
Geographic Name
Variant Geographic Name (R)
Type of Geographic Feature (R)
Other Classification Terms (R)
Geographic Feature Code (R)
Spatial Location (R)
Street Address
Related Feature (R)
Description
Geographic Feature Data (R)
Link to Related Source of Information (R)
Supplemental Note
Metadata Information


•   comprehensive description but with small set of core elements
•   temporal aspects of names, footprints, relationships, …
•   documents source, spatial accuracy/scale of footprint
•   does permit explicit relationship types!
      http://www.alexandria.ucsb.edu/gazetteer
                          Feature Typing
• need to incorporate a               hydrographic features
  dictionary of allowed terms         . aquifers
  which defines each feature
                                       . bays
  type
                                       . . fjords
• typing supports queries
                                       . channels
  such as
   –   “What schools exist in Leeds
                                       . deltas
       and where are they?”            . drainage basins
   –   Show lakes in Cornwall          . estuaries
• hierarchy of feature types           . floodplains
  preferred                           . streams
• propose to adopt the ADL             . . rivers
  Feature Type Thesaurus               . . . bends (river)
• some problems… but ADL               . . . rapids
  acknowledges these                   . . . waterfalls
• adapted thesaurus for UK
       geoXwalk gazetteer
   - current thematic content
(based on adapted ADL Feature Type Thesaurus)
                geoXwalk as digital
            gazetteer service: use cases


                                       Information
Geo-parsing &                             server

  indexing

                  The geoXwalk
                     Server


                                           Information
                                              server

                                 Searching

            Reference use
       Supporting reference: the “where is?” type
                       of question
    Where is Aberdour?
                         What is the largest town in Nottinghamshire?
What is at grid ref. NY 305 573 ?

                    List me all places ending with ‘kirk’

What parishes fall within the
Lake District National Park?
                                    On what river is Dundee situated?

   Which Roman roads pass                 By what alternative names
      through Scotland?                     has York been known?


    + research use to resolve variant names etc.
Demonstration
Task: Find resource about 'Liverpool docks‟
             Search using a „traditional‟ gazetteer might yield:

co-ordinates allow (near) co-located places
to be co-identified.
                                              Using spatial proximity in an active
                                              gazetteer, the search can be widened:
                                              Place           County/UA
                                              Liverpool       Liverpool
                                              Bebbington      Wirral
                                              Birkenhead      Wirral
                                              Bootle          Sefton
                                              New Brighton    Wirral
                                              Seacombe        Wirral
                                              Seaforth        Wirral
                                              Waterloo        Sefton
                                              … that means more
                                              & better hits …. !!!
Demonstration
   Supporting cross searching different
                 services
            „Find resources for this postcode‟
       (NB postcode often used to geo-reference survey data files)


      Post code: L34 0HS?                                    Co-ordinate footprints


                        340900,392300 - 347217, 397660
 Portal service


                                                                   Content
                                    Knowsley                      Provider A


                                                                  Place names
                            BX003


                                          Parish names
                                                                    Content
geoXwalk                                                           Provider B
 Server



                                        Content Provider C
Demonstration
  (Go-Geo!)
                          Protocols
• Why adopt a protocol at all?
   – agreed set of rules and interfaces (limit proliferation)
• ADL Query Protocol
   – lightweight, generic, relatively simple to implement
• OGC Filter Encoding Specification
   – fuller, highly flexible, more complex
• Z39.50
   – pervasive in JISC IE, not specifically for geo-spatial data,
     lack of support
                5 types of ADL query:

•   identifier-query identifier
    Return gazetteer entry identified by identifier
    Supported by geoXwalk

•   name-query operator text
    Returns gazetteer entries which match text under text-operator operator
    geoXwalk supports the mandatory equals operator and the
    optional match-pattern operator

•   footprint-query operator (polygon | box | identifier)
    Returns all gazetteer entries having a footprint that matches a query region
    according to spatial operator operator
    geoXwalk supports spatial operators within, contains and overlaps.
    Spatial extents can be specified by bounding box or identifier.
                       ADL queries (contd)


•   class-query thesaurus term
    Returns all gazetteer entries which belong to the class (feature type).
    geoXwalk supports class queries
    (but currently does not return sub-classes by default as the ADL does)


•   relationship-query relationship identifier
    Returns all gazetteer entries having relationship relationship to a
    target gazetteer entry identified by identifier.
    geoXwalk does not support queries of this type because we do not hold
    explicit relationships between entities - they are derived implicitly from the geometries
Demonstration
    m2m
           Outreach and evaluation
• JISCmail list established
• leaflet produced
• project web pages available
• discussions with various stakeholders
• discussions with data providers
• report and outcomes of this meeting will be written up

								
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