GML Data Models and Web Services for GPS and Earthquake Catalogs

1. GML Data Models and Web Services for GPS and Earthquake Catalogs Marlon Pierce, Galip Aydin Community Grids Lab, Indiana University mpierce@cs.indiana.edu

2. 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 WebServices for data exchanges, invoking queries, and filtering data.

3. What Are Web Services? • Web Services are not web pages, CGI, or Servlets • Web Services framework is a way for doing distributed computing with XML. • WSDL: Defines interfaces to functions of remote components. • SOAP: Defines the message format that you exchange between components. • XML provides cross-language support • Suitable for both human and application clients Browser Appl Web Server WSDL SOAP WSDL Web Server WSDL WSDL SOAP JDBC DB

4. 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.

5. 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.

6. 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.

7. Search DB For Earthquake Catalogs Results

8. Search XML DB For GPS Catalogs 1

9. 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

10. Fault Quest: QuakeTables+OGC Web Map Service Demo http://rio.ucs.indiana.edu:8080/wmsClient/

11. 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.

12. 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/

13. Browser Interface JSP + Client Stubs DB Service 1 Job Sub/Mon And File Services Viz Service JDBC DB Operating and Queuing Systems RIVA Host 1 Host 2 Host 3

14. QuakeSim Portal Shots

15. 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 datapedigree 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

16. Future Directions • We are interested in SemanticWeb 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

17. Acknowledgements • CommunityGrids: Geoffrey Fox, Choonhan Youn, Galip Aydin, Mehmet Aktas • NASAJPL: Andrea Donnellan (PI), Jay Parker, Peggy Li, Robert Granat • UC-Davis: John Rundle • UC-Irvine: Lisa Grant • USC: Dennis Mcleod • Brown: Terry Tullis

18. 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.

19. 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

20. QuakeSim Basics • Under development in collaboration with researchers at JPL, UC-Davis, USC, and Brown University. • Geoscientists develop simulationcodes, analysis and visualizationtools. • 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 remoteservice.

21. 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

22. 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

23. What Are Web Services? • Web services framework is a way for doing distributed computing with XML. • WSDL: Defines interfaces to functions of remote components. • SOAP: Defines the message format that you exchange between components. • XML provides cross-language support • Suitable for both human and application clients Browser Appl Web Server WSDL SOAP WSDL Web Server WSDL WSDL SOAP JDBC DB

24. 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