1. / department of mathematics and computer science TU/e eindhoven university of technology ITCC-Track on Modern Web and Hypermedia SystemsApril 29, 20031 RDF/XML-based Generation of Adaptable Hypermedia Presentations Flavius Frasincar flaviusf@win.tue.nl http://wwwis.win.tue.nl/~hera

2. / department of mathematics and computer science TU/e eindhoven university of technology ITCC-Track on Modern Web and Hypermedia SystemsApril 29, 20032 Contents Problem Hera Presentation Methodology Data Modeling: –Conceptual Model –Application Model –Adaptation Model Data Transformations Data Presentation in Different Browsers Conclusions

3. / department of mathematics and computer science TU/e eindhoven university of technology ITCC-Track on Modern Web and Hypermedia SystemsApril 29, 20033 Problem Present the data (possibly coming from different sources) on different platforms for different users in an automatic way

4. / department of mathematics and computer science TU/e eindhoven university of technology ITCC-Track on Modern Web and Hypermedia SystemsApril 29, 20034 Solution: Hera Hera is a model-driven methodology for hypermedia presentation design (part of Web Information System design) Hera differentiates from other existing model-driven methodologies by: –The high degree of automation of the designed system –The use of Semantic Web technologies (RDF, RDFS, RDF/XML) in system specification –The support offered for specifying adaptation aspects early in the design process

5. / department of mathematics and computer science TU/e eindhoven university of technology ITCC-Track on Modern Web and Hypermedia SystemsApril 29, 20035 Language/Tool Support Models are represented in RDF and they are serialized in RDF/XML User Agent Profile (UAProf): a Composite Capability/Preference Profiles (CC/PP) vocabulary to model device capabilities and user preferences XSLT processor for transforming between different model instances (stylesheet-based transformation): –Xalan (XSLT 1.0) –Saxon (XSLT 2.0): multiple output files support

6. / department of mathematics and computer science TU/e eindhoven university of technology ITCC-Track on Modern Web and Hypermedia SystemsApril 29, 20036 Data Modeling

7. / department of mathematics and computer science TU/e eindhoven university of technology ITCC-Track on Modern Web and Hypermedia SystemsApril 29, 20037 Conceptual Model (CM) Provides a uniform semantic view over different data sources that are integrated within a given Web application Consists of hierarchies of concepts relevant within the given domain Concept properties are: –Attributes: refer to literal values that characterize a concept –Relationships: refer to other concepts

8. / department of mathematics and computer science TU/e eindhoven university of technology ITCC-Track on Modern Web and Hypermedia SystemsApril 29, 20038 Example: CM

9. / department of mathematics and computer science TU/e eindhoven university of technology ITCC-Track on Modern Web and Hypermedia SystemsApril 29, 20039 Example: CM in RDF/XML <rdf:Property rdf:ID="creates" sys:cardinality="multiple" sys:inverse="created_by">

10. / department of mathematics and computer science TU/e eindhoven university of technology ITCC-Track on Modern Web and Hypermedia SystemsApril 29, 200310 Application Model (AM) Captures the logical (navigational) aspects of the presentation Based on the concept of slice, a meaningful presentation unit which contains attributes and possibly other slices: –A slice is associated to a concept from CM Slice properties are: –Aggregation properties: embed a set of slices (abstraction for index, tour, indexed guided tour etc). –Reference properties: link abstraction

11. / department of mathematics and computer science TU/e eindhoven university of technology ITCC-Track on Modern Web and Hypermedia SystemsApril 29, 200311 Example: AM

12. / department of mathematics and computer science TU/e eindhoven university of technology ITCC-Track on Modern Web and Hypermedia SystemsApril 29, 200312 Example: AM in RDF/XML <rdfs:Class rdf:ID="Slice.technique.main" slice:owner=“CM#Technique" slice:main="Yes"> <rdfs:Class rdf:ID="S.painting.picture" slice:owner=“CM#Painting" slice:attr-ref=“CM#picture"> <rdfs:Class rdf:ID="Slice.painting.main" slice:owner="CM #Painting">

13. / department of mathematics and computer science TU/e eindhoven university of technology ITCC-Track on Modern Web and Hypermedia SystemsApril 29, 200313 Adaptation Model Based on conditioning the appearance of slices A link referencing a slice that has the condition not valid is hidden Takes into account the device capabilities and user preferences based on two CC/PP vocabularies: –UAProf (User Agent Profile): device capabilities –UserProfile: user preferences The user/platform profile instantiates these two vocabularies for the specific platform and user of the system

14. / department of mathematics and computer science TU/e eindhoven university of technology ITCC-Track on Modern Web and Hypermedia SystemsApril 29, 200314 Adapted Application Model

15. / department of mathematics and computer science TU/e eindhoven university of technology ITCC-Track on Modern Web and Hypermedia SystemsApril 29, 200315 Example: AM in RDF/XML <rdfs:Class rdf:ID="Slice.painting.picture" slice:owner=“CM#Painting" slice:attr-ref=“CM#picture" slice:conditionSlice="prf:ImageCapable=Yes">

16. / department of mathematics and computer science TU/e eindhoven university of technology ITCC-Track on Modern Web and Hypermedia SystemsApril 29, 200316 Data Transformations Step 0: Preparation –Substep 0.1: Application Model Unfolding creates the skeleton of an AM instance –Substep 0.2: Application Model Adaptation adds slice visibility conditions to the previous skeleton –Substep 0.3: Main Transformation Specification Generation builds the specification for the next step Step 1: Main Transformation populates the AM with the input CM instance Step 2: Presentation Generation produces code for different browsers (HTML, WML, SMIL)

17. / department of mathematics and computer science TU/e eindhoven university of technology ITCC-Track on Modern Web and Hypermedia SystemsApril 29, 200317 Main Transformation Project all slices on the retrieved instances that correspond to the slice owner concept: –Each time a slice reference is encountered refer to its identifier (possibly traversing some instances based on concept relationship(s) from CM) * –Each time a media reference is encountered copy the media (given by a certain attribute from CM) * Name convention: –Slice full name: ‘Slice’+’.’+concept+ ’.’+ slice short name –Slice instance full name: Slice full name+ ’_’+ identifier of the instance projected upon

18. / department of mathematics and computer science TU/e eindhoven university of technology ITCC-Track on Modern Web and Hypermedia SystemsApril 29, 200318 Data Transformations

19. / department of mathematics and computer science TU/e eindhoven university of technology ITCC-Track on Modern Web and Hypermedia SystemsApril 29, 200319 Presentation in Browsers HTML SMIL WML HyperText Markup Language Synchronized Multimedia Integration Language Wireless Markup Language

20. / department of mathematics and computer science TU/e eindhoven university of technology ITCC-Track on Modern Web and Hypermedia SystemsApril 29, 200320 Conclusions Hera: –Is a model-based methodology that distinguishes two design tasks: the CM design and the AM design –It offers a high degree of system automation by specifying transformation stylesheets between different models –It uses standard technology: RDF, RDF/XML, XSLT As future work: –Support user interaction –Experiment with high level Semantic Web languages like the Web Ontology Language (OWL)