DAMLSpace

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DAML-Space

• Jerry R. Hobbs
• USC/ISI
• Marina del Rey, CA

with contributions from Rusty Bobrow, Murray
Burke, Dan Connolly, Dejing Dou, George Ferguson,
Andrew Gordon, Pete Haglich, Pat Hayes, Adam
Pease, Steve Reed, Richard Waldinger and others
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Context
The Semantic Web requires common ontologies
with wide acceptance and use. DAML-S an
ontology of services Development began
February 2001 About a dozen people in inner
circle Some people have explored using it
Institutional status at W3C Version 0.9
just released DAML-Time a temporal ontology
Development began February 2002 Most work
by 1-3 people Abstract theory 90 complete
Mapping between DAML-Time and TimeML One
site about to use it Want to build on this
experience for a spatial ontology.
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Aims
A widely available ontology of geographical
and other spatial properties and relations
Provide convenient markup and query
capabilities for spatial information in Web
resources Adequate abstract coverage of most
spatial applications (not necessarily
efficient) Link with special purpose reasoning
engines for spatial theories and
large-scale GIS databases Link with various
ontological resources (e.g., OpenCyc, SUMO,
...) and annotation schemes Link with various
standards for geographical information
(OpenGIS, GML, ...)
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Structure of Effort
Cohn
Hayes Chaudhri
Abstract Theory of Space (FOL)
etc
Complete or Partial Realization in DAML / OWL /
RuleML / ...
SUMO
OpenCyc
NLP Extraction Techniques
Existing Standards
Annotation Standards
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Some Principles
Delimiting the effort Not a theory of
physical objects, properties of materials,
qualitative physics Link with numerical
computation, dont axiomatize it Link with
large geographical DBs, dont duplicate them
Navigate past controversial issues by
Keeping silent on issue Provide easily
exercised options Use textbook logic for
abstract theory DAML/OWL-ize predicate and
function declarations Provide simple, useful
entry subontologies
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Topics
SPACE
TIME Topology
Topology Dimension
-- Orientation Shape
-- Length, area, volume
Duration Lat/long, elevation
Clock calendar Geopolitical
subdivisions -- Granularity
Granularity
Aggregates, distributions Temporal
aggregates
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Topology
Points, arcs, regions, volumes Closed loops and
surfaces Ordering relations between in arcs
directions on lines and loops Connectedness,
continuity Boundaries surfaces, interior
exterior, directed boundaries airspace
above Disjoint, touching, bordering,
overlapping, containing regions (RCC8)
location at Holes NOT open and closed sets NOT
pathological topologies
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Dimension and Orientation
Abstract characterization of dimension,
projections on component dimensions Links w
topological notions of dimension Frames of
reference earth-based, person-based,
vehicle-based, force-based Relative
orientations parallel, perpendicular Cartesian
vs polar coordinate systems, bearing
range Transformations between coordinate
systems Degrees of freedom Qualitative
trigonometry granularities on orientations 2 1/2
dimensions elevation as 2nd class dimension,
system mostly thought of as
planar Elevation from sea level vs ground
level Planar vs spherical geometry
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Shape
2D vs 3D shapes Linking w shape descriptions in
geographical databases Shape descriptors round,
tall, narrow, convex,... Relative shapes
rounder, sharper, ... Same shape as,
negative-shape, fits-in Symmetry Links w
functionality of shape In artifacts, shape
is almost always functional In natural
objects, shape often has consequences ? Texture
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Size
Length, distance, area, and volume Precise
measures Alternate descriptions of
size English-metric conversions Coarse
granularities order of magnitude, half order of
magnitude, implied precision, qualitative
measures (large, medium, small) relative to
comparison set Encoding uncertainty bounded
error, egg yolk theories Uncertainty of location
vs imprecise regions
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Granularity
A city can be viewed as a point, a region, or a
volume. How should these different perspectives
be accommodated? One approach City is an
entity with 3D, 2D, and 0D
realizations. User can pick which one(s) to
use. Build granularity considerations into
spatial ontology from the beginning, not as
an add-on.
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Spatial Aggregates
What are the most common ways of describing
spatial aggregates? A qualitative theory of
distributions. ? Texture
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Geopolitical Regions
Latitude and Longitude Natural geographical
regions Land masses continent, island,
... Bodies of water ocean, lake, river,
... Terrain features mountain, valley,
forest, desert, ... Political regions
Countries Political subdivisions state,
province, county, ... Municipalities city,
town, village, ... Residences and street
addresses Other Indian reservations,
regulatory zones, ...
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Linkages
Exploit the large amount of research on spatial
representation and reasoning OpenCyc, SUMO,
Cohn, Galton, Hayes Chaudhri, Hayes,
Asher Vieu, Egenhofer, Forbus Axiomatize best
of this work in coherent fashion Link with
existing large ontologies and annotation
schemes SUMO, OpenCyc Ontology should
bottom out in existing standards OpenGIS, GML
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Target Applications
As drivers for what has to be represented Flight
map system, COA planning, trafficability Travel
system involving lat/longs, political divisions,
weather Alexandrian Digital Library Geologic and
space (NASA) applications (3-D) Cell biology
Image interpretation and description Robotics Vir
tual reality For some of these, we are
collecting brief descriptions of the
requirements for spatial representation and
reasoning
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Organization
degree of community acceptance
of participants
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Organization
time to completion
of participants
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Organization
quality of ontology
of participants
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Organization
daml-spatial mailing list Web page - George
Ferguson Coherent construction of abstract
theories by small group of people Committee
of interested persons in U.S. and Europe
Email for commentary / feedback Telecons
every 2 weeks to track issues/progress
Presentations and discussion sessions at
relevant workshops Early realizations of
relevant parts of ontology in DAML Early
construction of application-oriented entry
subontologies