Towards RVL: a Declarative Language for Visualizing RDFS/OWL Data.
HTWK Leipzig / IMN ; TU Dresden / SMT / Softwaretechnology Group
Towards RVL: a Declarative Language
for Visualizing RDFS/OWL Data
HSWI Workshop at WIMS ‘13, June 14th 2013
Jan Polowinski (jan dot polowinski at tu-dresden dot de)
Clarification – What do we mean by „Visualizing“?
• Not: Structuring data into
textual documents +
Formatting / Styling
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• But: Visual encoding:
Define what data relations
correspond to what graphic
relations
Source: http://www.w3.org/2005/04/
fresnel-info/manual/#foafExample
Overall Goal: Reusable, Shareable Visual Mappings
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Visualization authors can
share and reuse „good“
visualization settings and
take their settings to other
tools!
Visualization
Author
Author of a domain ontology (just finished modelling)
Domain ontology authors can
propose visualization settings!
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Outline
• Principle of RVL
• Analysis: Requirements of RVL (Summary)
• Main constructs
• Composition
• Open Issues
• (Prototype RVL editors)
The Principle of RVL
Based on RDFS/OWL
itself
WIMS '13, Madrid, 28.06.13 RVL: A Language for RDFS/OWL Visualisation 5/30
Summary of the Analysis Preceeding the
Design of RVL
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Analysis of
• 3 domains: Life sciences, software requirements, publication
• 7 ontologies
• Frequently used concepts
Summary of the Analysis Preceeding the
Design of RVL
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Analysis of Visualisation Literature ..
• Graphic concepts + relations
• Formalized as ontology:
http://purl.org/viso/graphic/
Summary of the Analysis Preceeding the
Design of RVL
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Analysis for ...
• Common graphic
representations
• Identification of 12
Visualisation Cases (VC)
Summary of the Analysis Preceeding the
Design of RVL
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Examples for Visualization Cases:
• VC1 - Create a graphic object per resource.
• VC2 - Map to Graphic Attributes.
• VC5 - Define simple interactions.
• VC10 - Draw legends and labeled axes.
• VC11 - Define styles.
Summary of the Analysis Preceeding the
Design of RVL
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Deduction of 14 Language Requirements (LR)
• Examples ...
• LR-2: Multiple Visual Structures
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Examples of Concrete Language Requirements:
WIMS '13, Madrid, 28.06.13 RVL: A Language for RDFS/OWL Visualisation
• LR-2: Multiple Visual Structures
• LR-6: Platform Independence
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Examples of Concrete Language Requirements:
WIMS '13, Madrid, 28.06.13 RVL: A Language for RDFS/OWL Visualisation
• LR-2: Multiple Visual Structures
• LR-6: Platform Independence
• LR-12: Composability of Mappings
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Examples of Concrete Language Requirements:
Value Mappings
• Simple case: 1-to-1 explicit,
manual mapping of discrete
values
• Calculated value mappings
• Default: map whole range of
source values to the whole range
of target values
• Source and target values can be
refined ...
1
00
Value Mappings
• Simple case: 1-to-1 explicit,
manual mapping of discrete
values
• Calculated value mappings
• Default: map whole range of
source values to the whole range
of target values
• Source and target values can be
refined ...
• Order / Scale of measurement
can be re(de)fined ...
1
00
Composition of Visual Mappings
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• Simultaneous Composition
• Mappings all applied independently
• Trivial, except perceptional constraints (!)
• Context Composition
• Mapping only applies for a specific context
• Created by another mapping
WIMS '13, Madrid, 28.06.13 RVL: A Language for RDFS/OWL Visualisation
Which Visualisation Cases are Covered?
Most, except:
• Interaction
Ideas exist
• Complex „Standard“ Graphics
• Example: How to describe a TreeMap and the associated
algorithms?
• Reference a concept „TreeMap“?
• Keep flexibility of composition Current focus
• Integration of Formatting and Styling
Fresnel + CSS
WIMS '13, Madrid, 28.06.13 RVL: A Language for RDFS/OWL Visualisation 34/30
Summary
• We introduced a novel Language for visualizing RDFS/OWL data
• Rich capabilities to describe visual encodings
• Itself based on Semantic web standards
à Mappings have URIs
• Defaults allow for quickly handling common situations
• Design driven by concrete mapping situations
• Many mapping situations already covered
• Multitude of domains suggests some universality
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Future Work
• Further evaluate RVL
Tooling
WIMS '13, Madrid, 28.06.13 RVL: A Language for RDFS/OWL Visualisation 36/30
Two Prototypes for RVL Editing ...
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Future Work
• Further evaluate RVL
Tooling
• Cover remaining visualisation cases
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Thank you for your attention!
http://purl.org/rvl/
jan dot polowinski at tu-dresden dot de
PLEASE DISCUSS HERE OR
OFFLINE:
Schema of RVL
Relation to Fresnel
Advanced mapping compositions
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BACKUP SLIDES à
Acknowledgements
• This research has been co-funded by the European Social Fond / Free State of Saxony,
contract no. 80937064 and 1330674013 (eScience – network).
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BACKUP SLIDES à
Graphic Attributes and Graphic-Object-to-Object-
Relations
Graphic Attributes (GA)
• Lightness, Shape, Size, Named Colors
Graphic-Object-to-Object-
Relations (GOTOR)
• Linking Undirected
• Relative Position
• Separation by a Separator
à Formalised as
VISO Ontology
http://purl.org/viso/ 45/30
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RVL Schema
• What is a valid Mapping in RVL?
• SPIN Constraints used to describe Attributes, Defaults, ...
• Cardinality CS
• Type CS
• What is an effective mapping?
• Consistent handling of constraints which are based on VISO/facts is possible
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