Orientation to Methods
SOCoP 2012 Workshop
Gary Berg-Cross
SOCoP Executive Secretary
Nov. 29-30, 2012
U. S. Geological Survey National Center
12201 Sunrise Valley Dr., Reston VA
Outline
1. Intro to ODPs
2. Ontology Engineering
1. Problems, Component
and Relation
Identification &
Clarification
2. Conceptualization
Phase

3.
Systematic
organization & framing
with visual expression
Formalization
Geometry
A point is the most fundamental object
in geometry.
A point represents position only;
it has zero size
Geometry In NeoGeo Ontology
Super-class grouping all geometrical
representations
(includes non-RDF formats e.g. KML, GML,
WKT..)
URI http://geovocab.org/geometry#Geometry
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Examples of CPs
Colon
From PhD Course on Computational Ontologies @ University of Bologna
2011 Author(s): Valentina Presutti, Aldo Gangemi, Eva Blomqvist;
http://stlab.istc.cnr.it/documents/slides/PhDCourse/Bologna2011/ExtremeD
esign.pdf
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Conceptual Pattern- A Schema for Motion:
All paths
have a
start
point
We can generally outline what we mean by
Motion in a vocabulary of lexical terms to
represent concepts (Start of a Path) typically
used in this particular domain.
G
S
onPath
End point could
be represented in
a coordinate
system
We remain general in the pattern since this is a cognitive activity &
the concept has flexible semantics depending on human intentions
and perspectives. The pattern can generate alternate descriptions
conforming to alternate interpretations.
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Just OWL Classes
Motion is an
OWL:Class
Geo-VoCamp Patterns – Path from an info
perspective
is part of
Motion
hasPath
hasPath
Moving
Object
Path
-name
-start object
-end object
-path description
-medium
- surface
has part
Light constraints by relations
and what is related
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Point of Interest (POI) Pattern:
Geographic information constructs, not direct
representations of real entities
Groundable by
adding data not
more semantics
Some placeholders
Ideas for later
analysis.
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Composing New ODP from Old: Semantic Trajectory
•Preserves axioms
from other ODPs
•Adds concepts
Data for Model
:mikestrip a :SemanticTrajectory; :hasSegment [a :Segment; :from :fix1; // mikeshome:to :fix2;//
rest stop :traversedBy :fordFocus], [a :Segment; :from :fix1; // rest stop :to :fix2],//
WrightStateU :traversedBy :fordFocus], [a :Segment;:from :fix1; // WrightStateUniversity:to:fix2],//..
:fixn].:mike a foaf:Person:mikesFordFocus a motion:MovingObject.:garminEtrexVistaC a:Source.geo:
Geometry rdfs:subClassOf :Position.:mikesFordFocus a motion:MovingObject]:motion1 a……
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Step 1:Acquire Scoped Domain Knowledge & Vocabulary
Principle: Clarify & Indentify Problem, Components &
Relations
 Identify scope: We prefer working from scenario examples with potential data to help
structure requirements, defining the purpose of the ontology and illustrate the nature of
a problem topic.
 What are we talking about? What do you mean when you use these words..

Streams as objects (not processes?)…..
What is the scope? Not how streams flood, or pools of water,…
 What is the purpose of this modeling? What data is relevant….
We should leverage existing work but not slavishly
 leverage thoughts & experiences from other groups that are collaborating on
ontologies
 reference or include supporting vocabularies/ontologies,
Terminologies can be a starting point, but the path should be to the concepts behind
what the terms mean to domain people and be relatable to “data.”
 Controlled vocabularies and other terminologies are necessary lexical resources to
refer to concepts
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Linguistics or conceptual analysis
Handle multiple meaning and similarities
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Understanding from Definitions & Analysis
 Starts on partitioning experience into important/general parts & relations
 Example of semantics from definitions of a noun phrase “stream reach” –
what we are talking about?:
 a continuous part of a physical object stream (in a network) between
two specified points.


Reaches are commonly defined by a length of stream between two
confluences, or a lake or pond.
Addition - Stream - physical container hosting a void in which water can
be stored and through which it can flow.
Natural Aggregation
into Systems
Platt?
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Part of
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Some Design Detail on the Problem Space/System of
Stream Reach
Reaches in a stream network are segments of surface water with similar hydrologic
characteristics.
Each reach is assigned a unique reach number and a flow direction. (attributes)
The length of the reach, the type of reach, and differing important information are
assigned as attributes to each reach depending on perspective.
Ecologists and hydrologists will employ different concepts.
Monitoring
Void of
water
Reach
Point
R 101
Similar/uniform Characteristics
streamReach hasProperty, uniform
Flow to
downstream
end
Reach
Point
R 102
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Stream Reach by the Book – not everyday use
“Reach” means a watercourse that has a continuous channel bed that meets one of the
following requirements:
 (a) the channel bed is at least 100 m in length, measured from any of the following locations
to the next of any of the following locations:



(i) the location where the watercourse begins or ceases to have a continuous
channel bed;
(ii) the location where
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(iii) the location where
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(A) a significant change in morphology occurs, for example at the junction of a
major tributary, and
(B) the mean width of the channel bed, as measured over a representative
100 m length of channel bed, upstream and downstream of the
morphological change is sufficient to change the riparian class of the
watercourse, if the watercourse were a stream;
(A) a significant change in morphology occurs, eg at the junction of a major tributary, and
(B) the mean gradient of the channel bed, as measured over a representative 100 m length of
channel bed upstream and downstream the morphological change, changes from less than
20% to 20% or more, or vice versa;
(b) the channel bed is at least 100 m in length, made up of one or more segments, the
boundaries of which are any of the locations referred to in paragraph (a);
(c) the channel bed is less than 100 m in length, if the continuous channel bed



(i) is known to contain fish,
(ii) flows directly into a fish stream or a lake that is known to contain fish, or
(iii) flows directly into a domestic water intake.

See National Hydrography
Datasettohttp://nhd.usgs.gov/
& http://nhd.usgs.gov/nhd_faq.html#q105 11
Orientation
Semantic Methods for Workshop
Conceptualization Qualities
1.
Correctly captures intuitions of domain experts as they
express intended content (expressivity)
1.
These statements should be understandable to humans

E.g. Touches” is symmetrical (StramReach-101 touches
StramReach-102 so visa versa..Leg1ofTrip touches Leg2)
•
2.
3.
Formalization will make them processable by computing
systems.
Minimally redundant - no unintended synonyms
Multiple possible meanings of concepts are reduced so
that systems & people can recognize commonalities and
differences in the semantics of the concepts that they
use.
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Forge Consensus on Some of the Relevant Terms/
Concepts & Express
Container
To be a quality model (& later ontology) we should
be able to
 make meaningful statements about what exists
in our focused domain/topic and
 establish consensus about the meaning of
terms (in general)
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Outside
Inside
Aha!
Stream reach/segment is part of a stream
A pattern..
Streams and their parts are watercourses
Watercourses are containers
Watercourses may contain water
SpatialRegion
Stream segment/reaches have stream
direction
Steams have constituents
SpatialObject
Constituents had
Some stream reach constituents are uniform
in character…..
Controlled vocabulary suitable for OWL or CL helps
Contained
Object
Boundary
The water is in the stream.
The water is surface water.
The stream contains a water surface
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Conceptual Modeling & Design Phase
Frames, Organizes, Structures, Visualizes
Container Pattern
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Container IsA DUL:SocialObject
Container Contains Containee
Container hasLocation SpatialLocation
Place IsA SpatialLocation
Place denotesLocation Container


Axiom: Some ContainedObjects are DUL:PhysicalObjects
Axiom: Container contains 0-N contained objects……
Simple
CM
Language
Spatial Location Pattern??
Region IsA SpatialLocation
IsA Spatial Region
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Conceptual Modeling Activities
Design the overall conceptual structure of the domain.
This involves objects and their properties consistent with your purpose.
Focus on the Parts needed to build a Conceptual Models as a product
for input to Ontology
1.
Identifying & defining the domain's principal concrete concepts &
building a concept base (Objects ->Classes)
2.
Identifying the relationships among the concepts
1.
Arrange in taxonomical class hierarchy(s)
2.
Clarify IsA hierarchies and part-whole relations
3.
Link concepts via other Relations…..
3.
Discuss constraints that characterize key concepts and their
relations
1.
A Container may contain 0-n objects (empty container idea)
2.
FlowsInto relation is transitive
Add concepts & relations & individuals to the level of detail necessary to satisfy
your purposes.
All these will provide commitments
to tobe
expressed
in an ontological language
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Class Hierarchies, Attributes & Relations
(Path Ontology Examples)
Arranging objects as class hierarchies (supporting transitivity)
It depends on what vocabulary you adopt:
1. Path is a Feature, feature is a spatialThing, spatialThing is a Thing….OR
2. Path is a spatialFeature, spatialFeature is a PhysicalObject, (DOLCE) OR
3. Path is a Feature, Feature is a SpatialObject, SpatialObject is either a
Feature or a Geometry (GeoSPARQL model) See
1.
http://www.opengis.net/ont/OGC-GeoSPARQL/1.0/Feature
2. Attributes (class slots)
Path has a startObject, Path has a Name, Path has a Description
(“turn onto VA route 247”), some Descriptions are
PathGeometries,
Sunrise Valley Dr. hasQuantity Length
DataPropertyAssertion(.21 :hasValue : " "^^xsd:integer, hasUnit: miles ) ….
3. Relations (Properties) includes such ideas as Contains & hasPart
Path 101 hasPart Path101a,
Path101a
connectedTo
Path101b…..
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Am I Doing Structural, Ontological or Conceptual
Analysis & Design ?
 There are distinctions, but …

each can provide something from its best practices that helps
systematize the information.
Leveraging a Good Conceptual model the formal ontology should
represent:
 Meanings & Agreed upon Common Understanding
 Organization
Taxonomy etc.
 Basic Vocabulary as agreed upon
 Some instantible connection to the “real world” and data from it.
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
After Chris Welty’s: Ontology-Driven Conceptual Modeling
http://ontolog.cim3.net/file/resource/presentation/OntoClean
--ChrisWelty_20041118/OntoClean-2004v1--ChrisWelty_20041118.ppt
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Option of Aligning Concepts
 Each top-level concept in your model might be
loosely “aligned” to a top-level concept in a
foundational ontology like DUL.
 Given an alignment to top-level concepts, you
can “define” some the relations between them
perhaps by extending the foundational relations
that are used in ontologies like DUL to relate their
concepts.

memberOf and partOf are examples of
foundational relations.

We can use them…..
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Tools
 It is often useful to start with
hand/board drawings to
accommodate conversational
flow.
 PowerPoint graphics can be
used to tidy things up for
presentation.
 Better yet is a modeling tool like
CMAP with support for model
constructs and automatic
translation into OWL/TTL etc.
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Formally Committing to our Conceptualization with
Axiomatized Semantics
1. Formal –can be represented/put into a form
amenable to automated processing [formal
language]

1.
Ontologies formalize concepts with axioms
defined on such concept vocabularies
Sufficiently axiomatized – include detailed
constraining descriptions, such as transitivity,
as axioms (not just text descriptions)
2. Rigorous – stands up to rational analysis
1. Distinguish which concepts have instances
1.
Named classes can (potentially) have instances
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Formalization with Axiomatized Semantics
 RDFS is Modestly Formal - Used to Define a
Scale with a small concept vocabularies
scale:hasPoint (members);
2. rdfs:subPropertyOf scovo:datasetOf ;
3. rdfs:label "has point" ;
4. rdfs:comment "Associates a Scale with the Point(s) of
which it is comprised."
5. rdfs:domain scale:Scale ;
6. rdfs:range scale:Point .
1.
From VoCamp with Ordnance Survey
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Nearness Model- uses Scale Model
The web of logical statements carries
the meaning.
4 Point Scale of here, nearest, nearer
& close using before & after Properties
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Better Semantics Using OWL Language
 Transitive, inverse, symmetrical, reflexive/irreflexive
properties


Using RDFS we can’t say that:
isPartOf is a transitive property (branch isPartOf
River and tributary isPartOf branch),
Need Transitive property for Regions to say that the
subRegionOf property between regions is transitive
 <owl:TransitiveProperty rdf:ID="subRegionOf">
<rdfs:domain rdf:resource="#Region"/> <rdfs:range
rdf:resource="#Region"/> </owl:TransitiveProperty>
hasPart is the inverse of isPartOf or
A=A is reflexive but part relations are irreflexive
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These are things that can be
saidtoin
OWL
(Web
Ontology Language)
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Descriptive Logic
OWL uses a subset of 1st Order Logic called Descriptive
Logic (DL) that is decidable and simple enough to
represent and describe objects and properties
 Has a terminological (T-box) part to create
classes some by sub-typing and saying that
physical objects are a sub-type of object

<flood isa disaster>
 Has an assertional (A-box) part to describe
relations (other than sub-type) between instances
(Reston is_located_in VA) and to use axioms to
constrain meaning.
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Motion / Path RDF/ontology in Turtle (TTL):
(Terse RDF Triple Language – uses a . , ;])
Namespace prefixes
@prefix rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#> .
@prefix rdfs: <http://www.w3.org/2000/01/rdf-schema#> .
@prefix owl: <http://www.w3.org/2002/07/owl#> .
@prefix xsd: <http://www.w3.org/2001/XMLSchema#> .
@prefix geo: <http://www.opengis.net/def/geosparql/> .
@prefix sf: <http://www.opengis.net/def/sf/> .
@prefix gml: <http://www.opengis.net/def/gml/> .
@prefix dc: <http://purl.org/dc/elements/1.1/> .
@prefix spw:
<http://www.w3.org/2001/sw/BestPractices/OEP/SimplePa
rtWhole/part.owl> .
@prefix event: <> . @prefix :
<http://vocamp.org/ontology/movement/spatial/> .
(Default prefix)
# Ontology description :Ontology a owl:Ontology;
owl:versionInfo "0.5";
rdfs:comment “A geospatial instantation of the generic
Movement & Path pattern created at
GeoVoCampSB2012.";
dc:title "Spatial Motions and Paths" .
# Motion class
rdfs:comment "A motion is an event in which some entity
moves through space" ;
rdfs:subClassOf [
a owl:Restriction;
owl:onProperty :startEvent;
owl:allValuesFrom event:Event
];
:Motion a owl:Class;
rdfs:subClassOf event:Event;
rdfs:label "Motion";
rdfs:subClassOf [
a owl:Restriction;
owl:onProperty :endEvent;
owl:allValuesFrom event:Event
];
rdfs:subClassOf [
a owl:Restriction;
owl:onProperty :path;
owl:allValuesFrom :Path
];
rdfs:subClassOf [
a owl:Restriction;
owl:onProperty spw:hasPart;
owl:allValuesFrom :Motion
];
rdfs:subClassOf [
a owl:Restriction;
owl:onProperty :startEvent;
owl:allValuesFrom event:Event
].
A restriction class should have exactly one
triple linking the restriction to a particular
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Container in TTL for Owl
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@prefix xsd:
<http://www.w3.org/2001/XMLSchema#> .
@prefix DUL: <http://localhost/DUL#> .
@prefix rdfs: <http://www.w3.org/2000/01/rdfschema#> .
@prefix daml:
<http://www.daml.org/2001/03/daml+oil#> .
@prefix rdf: <http://www.w3.org/1999/02/22-rdfsyntax-ns#> .
@prefix owl: <http://www.w3.org/2002/07/owl#>
.
@prefix :
<http://localhost/default#> .
 :SpatialLocation

rdf:type owl:Class .
 :Place

rdf:type owl:Class ;

:IsA :SpatialLocation ;

:denotesLocation :Container .
 :Container

rdf:type owl:Class ;

:IsA DUL:SocialObject ;

:hasLocation :SpatialLocation .
 DUL:SocialObject

rdf:type owl:Class .
From CMAP draft
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