1. Reducing Maintenance Complexity of User-centric Web Portrayal Services
An alternate approach to web-based 3D Geodata Portrayal
Authors: Simon Thum and Michel Krämer
Simon Thum
Fraunhofer-Institut für Graphische Datenverarbeitung IGD Fraunhoferstraße Darmstadt Tel –

2. Application opportunities
Motivation
Our Approach
Where it fits in
Why it‘s different
Specific constraints
Our Solution
Characteristics
Outlook
Comparison
Application opportunities
Simon Thum: Reducing Maintenance Complexity ...

3. MOTIVATION
Simon Thum: Reducing Maintenance Complexity ...

4. MOTIVATION
Simon Thum: Reducing Maintenance Complexity ...

5. Portrayal complexity
Simon Thum: Reducing Maintenance Complexity ...

6. User-centric portrayal
Better matches specific user demands
Less knowledge in the client
Increased ability to adapt to acquisition idiosyncrases
Heterogenous, non-othogonal source data
Does not depend on spatial or semantic partitioning (overlap)
Less/no need for preprocessing
Always up-to-date
More a-priori knowledge in the portrayal service
Less client-side control
Run-time Overhead
Requires known datasource-wide identifiers

7. Data flow Source Select Render & Display Display Element G. End-User
Data Specialist
Simon Thum: Reducing Maintenance Complexity ...

8. Scenarios A Scenario is the central unit in our approach
Map to actual use cases
More technically: Coinciding portrayal requirements
Defined as a set of portrayal rules and their parameters
Constrain the anticipated portrayal problems we might need to solve
Enable the IR approach
Simon Thum: Reducing Maintenance Complexity ...

9. Information Item Representations
Decomposition
Portrayal Scenario
Requirements
Information Items
Information Item Representations
Simon Thum: Reducing Maintenance Complexity ...

10. Intermediate Representation
Explosion of interdependencies

11. Intermediate Representation
The IR is canonical information required to solve portrayal problems

12. Data heterogenity or „Fitness for Portrayal“
From information item representations to an IR item
Correlate sum
Category
Sufficiency
Solution
implicit
insufficient
ambient knowledge
[0..1[
partially sufficient
Inference (perhaps incuding ambient knowledge) 1
explicit
completely sufficient
n/a
> 1
arbitration
Simon Thum: Reducing Maintenance Complexity ...

13. Summary Knowledge about data sources is shifted closer to them
Client needs less knowledge
Scalable way to express and solve portrayal problems
Achieved by separating the concern of heterogenity
Less reliance on preprocessing
The approach has been tested at the local level
but should scale nicely
Doesn‘t fit well with client-driven approaches
Simon Thum: Reducing Maintenance Complexity ...

14. Thanks for your attention!
May I answer questions?
Simon Thum
Fraunhofer-Institut für Graphische Datenverarbeitung IGD Fraunhoferstraße Darmstadt Tel –