Socratenon Educational Web System

1. SocratenonEducational Web System D. Milicev, M. Milicevic, N. Nikolic,M. Trajkovic, V. MilutinovicUniversity of Belgrade Faculty of Electrical Engineering emiliced@etf.bg.ac.yu Find Your OwnRight Paththrough theDense Forest of the ContemporaryWeb Technologies!

2. Outline • Socratenon: The features • The forest: Contemporary web technologies and the complex requirements • The roadmap: The concepts and the method • The path: The infrastructure and the tools • Conclusions

3. Socratenon: The Features Why is Socratenon interesting? Purpose and main interfaces Students, courses, and curricula Virtual classroom Technical features

4. Socratenon’s Purpose • Education over Internet • Courses in industry and R&D • Adapt curriculum to student’s skills and preferences • Provide virtual classroom features • Log student’s activities and preferences

5. Socratenon’s Main Interfaces Student’s Teacher’s

6. Socratenon’s Main Interfaces Administrator’s Provider’s

7. Students, Courses, and Curricula • A course consists of learning objects; learning objects: presentations and tests

8. Students, Courses, and Curricula • Learning goals may be defined for each course; a learning goal is achieved by covering concepts

9. Students, Courses, and Curricula • A curriculum is created for each student • A curriculum may be changed according to student’s cognitive state and preferences

10. Socratenon’s Virtual Classroom • Grouping of students and other users • Messaging system • Forum • Logging and reports

11. Socratenon’s Technical Features • Simple and clear architecture • Light-weight implementation • Ideally portable • Extensible • Adaptable to client’s specific needs and preferences

12. The Forest: Contemporary Web Technologies... How to deal with complex requirements and tight schedule? Complex requirements and tight schedule Three-tiered internet architectures Infrastructural web technologies Integrational web technologies

13. The Complex Requirements • The story of the complex requirements... • The story of the tight schedule… • What we knew before...

14. Web Browser Client Web pages Internet Web Server &Application SQL Server Application Server Intranet Database Server Three-tier Web Architectures HTML Page HTML Request Query Result SQL Query

15. The Infrastructural Web Technologies • HTML/XML • COM/DCOM/ActiveX • CORBA/IDL • Java/JavaBeans/JavaScript • Applets/Servlets • DBMS/ODBC/JDBC

16. The Integrational Web Technologies • Visual HTML Editors and Site Managers • Web-Enabled Hypermedia Authoring Tools • HTML-DBPL Integrators • Web Form Editors, Report Writers, and Database Publishing Wizards • Model-Driven Application Generators

17. The Roadmap: The Concepts and The Method What is the right way through the forest? SW-RISC principle and SW-Amdahl’s law Typical man-machine interaction cycle The concepts The method

18. The SW-RISC Principle and the SW-Amdahl’s Law • SW-RISC: Find a small set of elements to combine and cover the complex domain • SW-Amdahl’s Law: Find a general pattern that covers 80% of use-cases; support it by the architecture that is open to be enhanced by classical methods and tools to cover the rest. 80% 20%

19. Starting Form Query Result Post SQL Update SQL Select Send HTML Client Application Server Database Server Ending Form Typical Man-Machine Interaction Cycle Data to fill the Page? Reformat HTMLwith the retrieved data Submit Find Next Page

20. Perform SQL Update query for C,with data from A’s controls as params Find the next form B Perform SQL Select query for C Fill the B’s controlswith the query results Send the filled form B to the browser Concepts: Forms and Commands Application Scenario Command C Form A Form B

21. course content +partsOfCourse +knowledgeContainer Course LearningObject * * * * PassivePresentation MultipleChoiceTest 1 1 * * Use casestextual definition Key abstractionstextual definition TestQuestions OO class model Database scheme OO use casedecomposition OO scenario definition The Method

22. Filled metadatabase Web applicationgeneration tool Working... OO scenario definition Running application Interpretation The Method (cont’d)

23. The Path: The Infrastructure and the Tools How to implement all these? The client side: HTML and web page designer The server side: Java and servlets The database: DBMS and JDBC The modeling: UML and Rational Rose

24. The Client Side • HTML • Web designer: Dreamweaver • Any other HTML page design tool

25. The Server Side • Java • Java and servlet environment: Kawa • Any other servlet-supporting Java programming environment

26. The Database • Relational database and JDBC • DBMS: Microsoft Access orSQL Server • Any other JDBC-supporting relational DBMS

27. The Modeling • UML • OO modeling tool: Rational Rose • Any other UML-supporting OO modeling tool

28. Conclusions What is done Lessons learned Further improvements Acknowledgements

29. Conclusions-What is done • Educational Web System that is: • rich in functionality • flexible and extensible • portable • Web-app development method that is: • flexible and extensible • rapid • easy to comprehend and apply

30. Lessons Learned • Do not get confused by the technology market • Choose the smallest set of methods and tools that can solve your problem • Apply the incremental and iterative, architecture-centric, risk-elimination driven approach

31. Further Improvements • Improvements of the infrastructure and method • Improvements of the user interface • Improvements of functionality • Development of graphical course design tools • Meeting the users’ needs...

32. Acknowledgements • The authors wish to thank toDejan Marjanovic who considerably contributed to the product implementation