Modelling Data-Intensive Web Sites with OntoWeaver

1. Modelling Data-Intensive Web Sites with OntoWeaver Knowledge Media Institute The Open University Yuangui Lei, Enrico Motta, John Domingue {y.lei, e.motta, j.b.domingue}@open.ac.uk

2. Outline • Motivation • OntoWeaver Rationales • Site View Modelling • Presentation Modelling • Customization Framework • An Example • Advantages and Limitations • Conclusions

3. Motivation • Data-intensive web sites • Time-consuming design process • Few re-usable components • Costly maintenance process • Solutions • Model-based web modelling methodologies • HDM, RMM, WebML, etc.

4. Customization Layer User Model User Profiles Customization Requirements PresentationLayer Layouts Presentation Styles SiteViewLayer Navigational Elements Data Elements KA Forms Query Forms DataLayer Data Services Databases Domain Model Current Research Practices

5. Open Issues • Limited support for the specification of site views; • RMM, OOHDM, HDM-Lite • ARANEUS, WebML, OntoWebber, HERA • Limited support for the specification of presentation styles and layouts; • Style sheets • Layout design • Limited support for customization at design time as well as at run time; • The customization specification is intertwined with the site view layer • The aspects of customization are limited

6. OntoWeaver: an Ontology-Based Approach • Goal: • to enable the process of designing ontology-based web applications to be carried out at the conceptual level • Rationales • Employing the notion of ontology as the back-bone • Site View Ontology • Presentation Ontology • Customization Framework • All aspects of a web site expressed declaratively • Advantages • Low-cost route to data-driven web applications • All aspects of a web site amenable to reasoning • Site Design Critiquing • Customization

7. Customization Layer User Model User Profiles Customization Requirements PresentationLayer Layouts Presentation Styles SiteViewLayer Navigational Elements Data Elements KA Forms Query Forms DataLayer Data Services Databases Domain Model Customization Framework Presentation Ontology Site View Ontology Domain Ontology

8. OntoWeaver: an Ontology-Based Approach • Goal: • to enable the process of designing ontology-based web applications to be carried out at the conceptual level • Rationales • Employing the notion of ontology as the back-bone • Site View Ontology • Presentation Ontology • Customization Framework • All aspects of a web site expressed declaratively • Advantages • Low-cost route to data-driven web applications • All aspects of a web site amenable to reasoning • Site Design Critiquing • Customization

9. OntoWeaver Architecture OW Web Site Site View Specification Presentation Specification Domain Ontology Site Designer Site Builder Site View & Presentation Ontologies Ontology Editor Site Customizer Inference Engine Online Page Builder User Profiles User Ontology Customization Rule Base Customized View

10. Modelling the Site View Layer Site hasResource hasIndexResource Resource hasMetaData hasComponent MetaData Component hasSubComponent hasSubResource hasCommand hasInput hasOutput SubResource Command Output Input hasLinkItem LinkItem

11. Examples of the Site View Constructs KA component Input element Command Element Output Elements

12. Data Component Dynamic Output

13. Site View Constructs Summary • Composite User Interface Constructs • Site, SiteResource, ResourceComponent • Component Primitives: • DataComponent • KAComponent • SearchComponent • Pre-defined services • Atomic User Interface Constructs • Output, DynamicOutput, Command, Input • Navigational Constructs • LinkItem, DynamicLinkItem, Parameter

14. Modelling the Presentation Layer • Presentation Styles • Fonts, colours, etc • Template-based approach • Templates: generic templates, widget templates, data component templates • Presentation objects: attaching templates with site view components • Layouts • Organization of site view components • Layout modelling • Text Layout • Component Layout • Presentation Model • SitePresentation

15. SitePresentation hasTemplate hasLayout hasPresentation Layout Template hasAreaLayout Presentation hasTemplate AreaLayout hasComponentURI PresentationTemplate ComponentURI ComponentURI Presentation Model

16. Customization Framework • Declarative Site Model • Site view specifications; • Site presentation specifications; • Site ontologies. • User Ontology • A model to enable the recording of user profiles • Only very basic ontology is provided, typically this will be specialised for particular applications • User Profiles • Information about end users in terms of user ontology. • Customization Rules • Conditions • Customization Actions • Jess Inference Engine

17. OntoWeaver Architecture OW Web Site Site View Specification Presentation Specification Domain Ontology Site Designer Site Builder Site View & Presentation Ontologies Ontology Editor Site Customizer Inference Engine Online Page Builder User Profiles User Ontology Customization Rule Base Customized View

18. Example: Building a Paper Review System • Four types of users • Authors • They browse conference information • They submit papers • Reviewers • They get the papers assigned for review from the web site; • They submit their reviews to the web site; • Program committee members • They browse review recommendations. • Chair • Has access to everything, notifies authors, etc.

19. Design Process • Domain Ontology Design: • Site View Design: • Designing navigational structures • Composing user interfaces for web pages • Presentation Design • Specifying visual appearance for user interface elements • Specify layout for user interface elements • Customization Design: • Identifying potential audiences; • Creating different site models for different user groups; • Defining customization rules for individual users or groups;

20. OntoWeaver Site Designer

21. A General View

22. User Group Specified Customization

23. Rule-based Customization

24. A Customized View For Paper Reviewers • Reviewers get extra links for obtaining assigned papers and submitting reviews; • Two corresponding new web pages have been created; • Customized web pages are generated on the fly when users whose role is “Reviewer” login onto the paper review system and make requests about web pages.

25. Advantages • High level specification • The design can be made much simpler • Automatic site generation through ontology mapping • Customization support • The modular approach • The customization framework • Site maintenance • Tools support for manual and semi-automatic maintenance

26. Limitations • Focusing on data presentation, data acquisition, and data querying • Remote web services are not considered • Semantics of web pages are not explored

27. Conclusions • OntoWeaver uses an ontology-driven approach to the design and development of data-intensive web sites. • It provides a set of ontologies to support the modelling and specification of all aspects of data-intensive web applications. • It provides a customization framework to allow the specification of customization requirements at a high level of abstraction. • It provides a tool suite to support the design and development of data-intensive web istes.