Transcript Generalisation and the AGENT Project

Generalisation and
The AGENT Project
Sylvie Lamy
IGN
With much help from the AGENT partners
(Laser-Scan, Zurich, Edinburgh, INPG)
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Cartography and Generalization
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Generalisation = deriving smaller scale mapping from
more detailed mapping or detailed source data
Science and art of exaggerating that which is important,
and removing irrelevant detail that would clutter and
confuse
IGN 1:25,000
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Automated Generalisation
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Still need paper products at different scales
Increasingly important for “mapping on demand“,
particularly internet web mapping
AGENT =
Automated GEneralization New Technology
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What Is an Agent ???
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Real or virtual entity, e.g. active software
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Evolves in an environment
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Is able to perceive and act in this environment
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Can communicate with other agents
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Exhibits, as a consequence of the above, an
autonomous behaviour
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Reactive (simple) or cognitive (more
complex)
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Multi-agent systems (MAS) have collaborative
global
goals
as well
individual
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Micro-agents are Individual
Features e.g. a Building
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Building Constraints
 Size constraint: building should have a
minimum size to be legible. This size
depends on scale and symbol thresholds
 Width constraint: The width within a building
should be wide enough to avoid conflict
 Accuracy constraint: The absolute position of
a building should be preserved as much as
possible
 Orientation constraint: The orientation of a
building should be preserved
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From Constraints to Goals
 I should be big enough
 I should be wide enough
 I should try to preserve my shape
 I should not be too far from my initial position
 I should try to preserve my original orientation
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Goals
 Size:
> 300m2
 Internal width:
> 20m
 Hausdorff dist:
< 20m (from initial position)
 Main orientation:  [initial-main_orient - 0.1,
initial-main_orient + 0.1]
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Analysis of a Building
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Finding an Acceptable
Solution
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Agent Base Class - State Diagram
start_state
initialize
characterize
Measures
evaluate
Constraints
propose
Actions
trigger
if hapiness is worse,
act_best_plans(plans)
conclude
start_state
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Meso-agent - Coordinating
Constraints / Goals
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Ensure minimum
distance
Keep alignment
Keep share
relationships
...
Actions
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Displace
Amalgamate
Eliminate
...
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Why Meso-agents ?
Building Generalization Needs
Knowledge of Neighbours
© IGN
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Demonstrators from the
AGENT project
P1
P2
Internet access
Multi-scale Production
On-demand
Transportation
Mapping
1:50K Derived
Topographic
Mapping
Gothic Database
MULTI-AGENT SYSTEM
1:10K Data
Transportation
Specifications contained
Classes:
Symbology:
Constraints:
proximity
accuracy
Export
Hardcopy
within database
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The AGENT Project Partners
Institut Geographique
National (leader)
University of
Edinburgh
Institut National
Polytechnique de
Grenoble
Laser-Scan Ltd.
EC funding
ESPRIT 24939
University of
Zurich
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AGENT Project
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21 man years over 3 year period
Aims of research:
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Better algorithms
Better measures
Better constraints
Better decisions via multi-agent systems
Results are reports, prototype implementation,
and 2 demonstrators
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Current Status of Project
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About half-way, and on schedule
Independent generalisation (micro-agents) is
implemented and being refined
Contextual generalisation (meso-agents) is
being developed now
Strategic generalisation (macro-agents) is
next year
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