Specification of Adaptive Behavior Using a General-purpose Design Methodology for Dynamic Web Applications

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Specification of Adaptive Behavior Using a
General-purpose Design Methodology for Dynamic
Web Applications

• Databases and Hypermedia Group

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Outline

• AHS and Modern WIS
• Hera Methodology
• Adaptive Application Design Example
• Implementation
• Conclusion

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Adaptive Hypermedia Systems

• Monitor users actions
• Dynamically update a user model
• Based on the user model adapt an applications
  user interface

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Modern WIS

• Are based on the Web
• Provide complex services (functionality)
• Use data distributed over Internet
• Have large audience (need of personalization)

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WIS Architecture
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Hera, a Model-driven Methodology

• Conceptual Model (CM) describes data content used
  for generation of hypermedia presentations)
• Application Model (AM) describes the navigation
  structure and functionality
• Presentation Model (PM) describes spatial layout
  and rendering of hypermedia presentations

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Hera WIS Architecture
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Example Adaptive Application in Hera

• Stores information about books and authors
• Stores users selection of books (shopping
  basket)
• Calculates user interest in particular authors
  (based on the user selection) and shows info
  about the most interesting authors

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Example CM and Navigation Data Model

• NDM extends CM with notion of updatable context
  information (user selection, interests)

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Example AM

• Defines the navigation structure and functionality

• Creates and deletes basket instances
• Creates Interest instances
• Increases Interest.degree for authors of selected
  books
• Decreases Interest.degree for other authors

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Hera Engine Implementation

• Runs as a servlet under Apache Tomcat Web server
• Uses the HP Jena RDF API for import of models
  (CMNDM, AM)
• Uses the Sesame RDF data repository for
  navigation data (also for the main data content),
  queries and data manipulations are in SeRQL/RQL

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Conclusion

• It is possible to model (and implement) an
  adaptive hypermedia system using a
  general-purpose WIS design methodology
• Model-driven methodologies allow schema-level
  adaptation
• Possible adaptation techniques depend on a
  concrete methodology for current version of Hera
  it is only conditional inclusion of fragments
  (slices)

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Questions?