GML Data Models and Web Services for GPS and by vev19514

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									GML Data Models and Web
  Services for GPS and
  Earthquake Catalogs
    Marlon Pierce, Galip Aydin
      Community Grids Lab,
        Indiana University
     mpierce@cs.indiana.edu
               QuakeSim Applications
   Several QuakeSim codes work directly with
    observational data.
   Examples discussed at ACES include
    • GeoFEST, VirtualCalifornia, Simplex, and Disloc all depend
      upon fault models.
    • RDAHMM and Pattern Informatics codes use seismic
      catalogs.
    • RDAHMM primarily used with GPS data
   Problem: We need to provide a way to integrate
    these codes with the online data repositories.
    • QuakeTables Fault Database was developed
    • What about GPS and Earthquake Catalogs?
    • Many formats, data available in tars or files, not searchable,
      not easy to integrate with applicaitons
   Solution: use databases to store catalog data; use
    XML (GML) as exchange data format; use Web
    Services for data exchanges, invoking queries, and
    filtering data.
        What Are Web Services?
   Web Services are not web
    pages, CGI, or Servlets       Browser
   Web Services framework is
    a way for doing distributed                                Appl
    computing with XML.
    • WSDL: Defines interfaces
      to functions of remote       Web                        WSDL
      components.                 Server
    • SOAP: Defines the                                            SOAP
                                  WSDL
      message format that you
      exchange between




                                                            WSDL
                                            WSDL
      components.                                   Web
    XML provides cross-                            Server
                                 SOAP
    language support
   Suitable for both human                              JDBC
    and application clients

                                                    DB
    Geographical Information Service
    (GIS) Data Formats and Services
   OpenGIS Consortium is an international group for defining
    GIS data formats and services.
   Main data format language is the XML-based GML.
    • Subdivided into schemas for drawing maps, representing
      features, observations, …
   First Step: design GML schemas and build specialized Web
    Services for GPS and Earthquake data.
   OGC also defines services.
    • Services include Web Features Services, Web Map Services,
      and similar.
    • These are currently pre-Web Service, based on HTTP Post, but
      they are being revised to comply with WS standards.
   Next Step: Implement OGC compatible Web Services for
    this problem.
    • Also build services to interact with QuakeTables Fault DB.
GML and Existing Data Formats
   GPS or seismic data used in this project
    are retrieved from different URLs and
    have different text formats.
   Seismic data formats
    •   SCSN, SCEDC, Dinger-Shearer, Haukkson
   GPS data formats
    •   JPL, SOPAC, USGS
   We defined 2 GML Schemas to unify
    these
    • http://grids.ucs.indiana.edu/~gaydin/servo
   A summary of all supported formats and
    data sources can also be found there.
                 So We Built It
   First version of the
    system available
    • Tried XML databases
      but performance was
      awful
    • Currently database uses
      MySQL
   Download results are
    in GML, but we can
    convert to appropriate
    text formats.
Search DB For Earthquake
        Catalogs




              Results
Search XML DB For GPS Catalogs




     1
    Use Ours or Set Up Your Own
   URL to access our browser interface:
    • http://gf3.ucs.indiana.edu:6060/cce/sql/
   URL to download and set up your
    own
    • http://complexity.ucs.indiana.edu/~gaydin/cce
      /install/install.html
Fault Quest: QuakeTables+OGC
    Web Map Service Demo




http://rio.ucs.indiana.edu:8080/wmsClient/
               Conclusions
   This is a little discussion with a big
    conclusion--
   If you want to build iSERVO or
    something like it, data access
    services are an important
    foundation.
    GML Schemas as Data Models for
             Services
   Fault and GPS Schemas are based on GML-
    Feature object.
   Seismicity Schema is based on GML-Observation
    object.
   Working schema available from
    http://grids.ucs.indiana.edu/~gaydin/schemas/
               Browser Interface




               JSP + Client Stubs




                Job Sub/Mon
DB Service 1      And File          Viz Service
                  Services

JDBC


                Operating and
    DB            Queuing              RIVA
                  Systems

   Host 1           Host 2             Host 3
QuakeSim Portal Shots
                        Other Issues
   We want to abstract the data storage system to allow
    simple federation of relational and XML databases
    • UK e-Science’s OGSA-DAI project is an interesting but
      complicated example.
           We’d like to simplify this approach
   Metadata is also important
    • Useful for capturing data pedigree and validation.
           “This fault data generated with Simplex by Jay Parker using the
            parameters….”
           “Those 1935 Fault measurements aren’t so good.”
   We have developed some general applications for metadata
    management
    • Newsgroups, citations, references, glossaries as examples.
    • Would like to apply to scientific metadata
                Future Directions
   We are interested in Semantic Web markups (particularly
    RDFS) to provide metadata descriptions of
    •   Instruments
    •   Data sets
    •   Computing hardware
    •   Applications/codes
   We want this to form the basis for building composite
    services.
   Infrastructure improvements: reliable, fault tolerant grid
    infrastructure needed as grid components come and go.
   Component based portals: reuse portal interfaces between
    projects.
   ISERVO: International collaborations with Australia, Japan,
    and possibly other countries
    • Through ACES: APEC Cooperation for Earthquake Simulation
         Acknowledgements
   Community Grids: Geoffrey Fox,
    Choonhan Youn, Galip Aydin,
    Mehmet Aktas
   NASA JPL: Andrea Donnellan (PI),
    Jay Parker, Peggy Li, Robert Granat
   UC-Davis: John Rundle
   UC-Irvine: Lisa Grant
   USC: Dennis Mcleod
   Brown: Terry Tullis
     Problems: Data Access and
      Sharing, Code Integration
   Codes all use custom text formats for
    describing input and output.
   Input and output data often combined
    with code-specific information.
    • Number of iterations, array sizes, etc.
   Data files often created by hand from
    journals, online repositories
    • Online repositories themselves use differing
      formats
   Challenges are to develop common data
    formats, access services, and client
    query tools.
Web Services for Data Access and
 Computing Service Invocation
   Web services:
    • WSDL: Interface definition language, describes your
      service
          “GeoFEST may be invoked with these input types”
    • SOAP: Transport envelope for remote procedure
      calls/messages
          “Invoke GeoFEST with this set of input”
   Together, WSDL and SOAP are useful for
    manipulating, returning XML data values
    • So GML schemas act as our data models and return
      values
   Status: built several general purpose services
    • Remotely executing codes, monitoring queuing systems,
      manipulating/moving files around, describing
      applications, storing portal session values, accessing
      data bases of faults,…
   Work underway to build data services
            QuakeSim Basics
   Under development in collaboration with
    researchers at JPL, UC-Davis, USC, and
    Brown University.
   Geoscientists develop simulation codes,
    analysis and visualization tools.
   We need a way to bind distributed codes,
    tools, and data sets.
   We need a way to deliver it to a larger
    audience
    • Instead of downloading and installing the code,
      use it as a remote service.
            What’s the Problem?
   Data sources typically were provided in single downloads
    • Tar bundles or text
    • This has changed for SCEC catalogs since we developed this
      project.
    • SCIGN is adopting a Web Services approach for GPS data.
   Formats defined but presented as text
    • Use XML to re-format the data.
    • Buys us investment in many XML manipulation, validation, and
      messaging tools.
   We wanted to use databases to store and manage the
    information.
   This makes the data queryable
    • Retrieve all entries > 1970
    • Retrieve all entries with M>3.0
      Data Sources Summary
   A summary of all supported
    formats can be found here
    • http://grids.ucs.indiana.edu/~gaydin/
      servo
   Information about supported
    Earthquake catalog formats can be
    found in
    http://www.data.scec.org/
   Information about supported GPS
    data formats can be found in
    http://www.scign.org
        What Are Web Services?
   Web services framework is
    a way for doing distributed   Browser
    computing with XML.
    • WSDL: Defines interfaces                                 Appl
      to functions of remote
      components.                  Web                        WSDL
    • SOAP: Defines the           Server
      message format that you                                      SOAP
      exchange between            WSDL
      components.




                                                            WSDL
                                            WSDL
                                                    Web
   XML provides cross-
                                                   Server
    language support              SOAP
   Suitable for both human
    and application clients                              JDBC


                                                    DB
     Delivering Data for Human and
       Application Consumption
   We still have to get the results to the
    (remote) client.
   The client may be a user or an application.
   Web Services provide a way to do this.
   Note Web Services are NOT
    • Web pages
    • Servlets
    • CGI scripts

								
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