/ faculty of mathematics and informatics TU/e eindhoven university of technology ADBIS'200128/09/20011 An RMM-Based Methodology for Hypermedia Presentation Design Flavius Frasincar Richard Vdovjak Geert-Jan Houben Databases & Hypermedia Group Department of Informatics

/ faculty of mathematics and informatics TU/e eindhoven university of technology ADBIS'200128/09/20012 Contents 1.Motivation 2.Goals 3.Context: Hera Architecture 4.Design Methodology 5.Application Diagram 6.Presentation Diagram 7.Prototype: XML/XSL 8.Further Work

/ faculty of mathematics and informatics TU/e eindhoven university of technology ADBIS'200128/09/ Motivation There are a lot of methodologies for manual hypermedia presentation design but not for an automatic one. The need for presentation automation is justified by the fact that a lot of data is nowadays residing in the heterogeneous ‘deep web’ (searchable databases) as opposed to the ‘surface web’. There is an increasing need for presentation adaptation for different users/user platforms.

/ faculty of mathematics and informatics TU/e eindhoven university of technology ADBIS'200128/09/20014 Deep Web Deep Web vs. Surface Web: 500 times larger 1000 times better quality

/ faculty of mathematics and informatics TU/e eindhoven university of technology ADBIS'200128/09/ Goals Develop a methodology that supports automated hypermedia presentation design for Web-based Information Systems (WIS) that: –Integrates heterogeneous data sources. –Facilitates presentation (server/client-side) adaptation: Network (T1, 128K, 56K etc.) Display (PC, Palm, WAP Phone etc.) User (preferences, interaction history etc.) –Enables semi-structured data queries.

/ faculty of mathematics and informatics TU/e eindhoven university of technology ADBIS'200128/09/ Context: Hera Architecture Relational Database Object-Oriented Database XML Database ODB-XML Wrapper RDB-XML Wrapper Mediator/ Integrator Logical Presentation Logical-WML Presentation HTML Presentation SMIL Presentation WML Presentation Logical-SMIL Presentation Logical-HTML Presentation Information Retrieval Hypermedia Presentation … … Query

/ faculty of mathematics and informatics TU/e eindhoven university of technology ADBIS'200128/09/ Design Methodology Based on RMM (Relationship Management Methodology). It distinguishes two levels: –Logical level: groups data into meaningful content units, called Slices. Artifact: Application Diagram –Presentation level: translates slices to presentation units, called Regions. Artifact: Presentation Diagram

/ faculty of mathematics and informatics TU/e eindhoven university of technology ADBIS'200128/09/20018 Methodology Phases Requirements Analysis E-R Design Application Design Presentation Design Implementation E-R Diagram Application Diagram Presentation Diagram Entity Relationship Slice Slice Relationship Region Region Relationship (Conceptual Model) (Application Model) (Presentation Model) Phase Artifacts:

/ faculty of mathematics and informatics TU/e eindhoven university of technology ADBIS'200128/09/ Application Diagram Based on the concept of slice which groups together attributes (having specific media types) and possibly other slices. Extends the E-R Diagram, each slice belongs to an entity. Slices are linked together with slice relationships: –Aggregation relationships: index, tour, indexed guided tour etc. –Reference relationships: link with an anchor specified.

/ faculty of mathematics and informatics TU/e eindhoven university of technology ADBIS'200128/09/ Application Diagram Example

/ faculty of mathematics and informatics TU/e eindhoven university of technology ADBIS'200128/09/ Presentation Diagram Based on the concept of region which contains attributes and possibly other regions. Each region has a rectangular area associated. Slices are translated to regions, one slice can be mapped to several regions. Slice relationships are materialized with: –Navigational relationships –Spatial relationships –Temporal relationships

/ faculty of mathematics and informatics TU/e eindhoven university of technology ADBIS'200128/09/ Region Relationships All region relationships can be guarded by a condition and/or an event. Navigational relationships: represent the classical hyperlinks. Possible events are: mouse-click, mouse-over etc. Temporal relationships: have associated a timeout event (e.g. time based on a media play duration). Spatial relationships: specify a relative position (qualitative or quantitative) between two regions.

/ faculty of mathematics and informatics TU/e eindhoven university of technology ADBIS'200128/09/ Presentation Diagram Example

/ faculty of mathematics and informatics TU/e eindhoven university of technology ADBIS'200128/09/ Synchronization Petri-net like notation for expressing synchronization (typical for multimedia data). Temporal Multidimensional

/ faculty of mathematics and informatics TU/e eindhoven university of technology ADBIS'200128/09/ Prototype: XML/XSL Implements the logical level of the design methodology. Based on transformation steps encoded in XSL stylesheets that describe to an XSLT processor how to convert the input XML file to the desired output XML file. Tool: XSLT processor from Apache XML Project.

/ faculty of mathematics and informatics TU/e eindhoven university of technology ADBIS'200128/09/ Prototype Steps

/ faculty of mathematics and informatics TU/e eindhoven university of technology ADBIS'200128/09/ Data Retrieval Retrieved data is an instance of the conceptual model. DTDXML

/ faculty of mathematics and informatics TU/e eindhoven university of technology ADBIS'200128/09/ Data Cleaning Enriches the retrieved data with information from the application domain model (appropriate relationship names, inverse of relationship instances). relationship.exemplifies XSL

/ faculty of mathematics and informatics TU/e eindhoven university of technology ADBIS'200128/09/ Application Model Describes at logical level the hypermedia aspects of the application. DTDXML <!ELEMENT slice (text | (slice-ref | hyperlink | index | guided-tour))> <slice id=“slice.painting.main” owner=“entity.painting”> relationship-ref=“relationship.painted_by”/> …

/ faculty of mathematics and informatics TU/e eindhoven university of technology ADBIS'200128/09/ Logical Transformation Generation Builds the main transformation engine that packages the retrieved data into slices using the application model. <xsl:stylesheet xmlns:xsl=“ xmlns:axsl=“ … … XSL

/ faculty of mathematics and informatics TU/e eindhoven university of technology ADBIS'200128/09/ Logical Transformation Packages the retrieved data into slices based on the stylesheet generated by the previous step. XSL

/ faculty of mathematics and informatics TU/e eindhoven university of technology ADBIS'200128/09/ XSL Presentation Transformation Implements the presentation. There are two code generators built for: HTML and WML. XSL HTML WML

/ faculty of mathematics and informatics TU/e eindhoven university of technology ADBIS'200128/09/ Further Work Add media types to the model (now: strings and URLs). Build slices-on-demand on a servlet (now: precomputed). Implement the presentation level of the proposed methodology. Make use of query technologies for XML and RDF: XQuery and RQL (now: SQL). Experiment with different kinds of applications (e.g. Electronic TV-Program Guide). Use Semantic Web: model descriptions in RDF(S). –Taxonomies of classes/properties based on inheritance.