1. n NESSTAR: A Semantic Web Application for Statistical Data and Metadata Pasqualino “Titto” Assini Nesstar Ltd - UK

2. Nesstar - Networked Social Science Tools and Resources n nesstar NESSTAR: NEtworked Social Science Tools And Resources (a.k.a. the “Data Web”) –What is all about? The domain: statistical information. –What is the “Data Web”? –End User and Data Publisher Views –Requirements The Underlying Architecture: NEsstar Object Oriented Middleware (NEOOM) –Web Oriented: based on Semantic Web technology –Object Oriented –Domain Independent Implementation Design and Development Process Contents

3. Nesstar - Networked Social Science Tools and Resources n nesstar The Domain: Surveys, Opinion Polls, Censuses The Actors: –Data Publishers: Social Sciences Data Archives, Statistical Offices, Private Research Institutes (Gallup, etc) –Data Users: Social Researchers, Journalists, Marketing Experts The Problem –Simplify publishing, finding and accessing statistical information. The Domain and the Problem

4. Nesstar - Networked Social Science Tools and Resources n nesstar The Web is a very successful example of a distributed information dissemination system Can we learn something from the Web? Idea: Use (Semantic) Web principles and technologies to create a “Data Web” Learning From the Web

5. Nesstar - Networked Social Science Tools and Resources n nesstar What is the Data Web? The Data Web is the application of Semantic Web techniques and principles to the problem of distributed data dissemination and processing.

6. Nesstar - Networked Social Science Tools and Resources n nesstar User view: Data Web Browser LOCATION BAR OBJECT BROWSER BOOKMARKS OPERATION OPERATION RESULT BROWSING

7. Nesstar - Networked Social Science Tools and Resources n nesstar Publisher View: Object Model PROPERTIES RELATIONSHIPS TYPE METHODS INHERITANCE

8. Nesstar - Networked Social Science Tools and Resources n nesstar Requirements Support for the Object Model: –An interface definition language that supports Types, Properties, Relationships and Methods  RDF Schema (no Methods) Distributed object model extensibility: –Inheritance  RDF Integration with the Web: –Objects, Types and method invocations have a URL –Object state is accessible via HTTP  Objects (and types) self-describe themselves in RDF –Method invocations can be performed via HTTP  SOAP, HTML FORM

9. Nesstar - Networked Social Science Tools and Resources n nesstar Semantic Web (RDF/RDF Schema) plus: –Self-description principle: objects and types self- describe themselves by making accessible their RDF description at their URL (dynamic discovery) –RDF Schema Model for Methods –Method Invocation Protocol based on HTML FORM Nesstar Object Oriented Middleware

10. Nesstar - Networked Social Science Tools and Resources n nesstar Method Model

11. Nesstar - Networked Social Science Tools and Resources n nesstar Method Invocations are: –Performed as HTML FORM methods  Very easy to generate forms that correspond to method invocations –Coded as normal URLs: Ex: http://15.245.54.37/obj/Server?..method=Login &userID=admin&userPassword=mypwd Method Invocation Protocol

12. Nesstar - Networked Social Science Tools and Resources n nesstar A machine-understandable Data Web closely integrated with the (Semantic) Web. Advantages: –Support for sophisticated Object Oriented Models –Distributed Extensibility –Integration with the (Semantic) Web –Compatibility With Existing Languages/Protocols/Applications –Programming Language Independence What Have We Got?

13. Nesstar - Networked Social Science Tools and Resources n nesstar System Components

14. Nesstar - Networked Social Science Tools and Resources n nesstar Design/Development Use Cases

15. Nesstar - Networked Social Science Tools and Resources n nesstar Presentation Layer Independence

16. Nesstar - Networked Social Science Tools and Resources n nesstar Web Links to Statistical Objects This is a Nesstar Server object … Get linked objects

17. Nesstar - Networked Social Science Tools and Resources n nesstar Web Links to Statistical Operations

18. Demo Object Browser (new EJB Server)Object Browser Data Archive Server