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Brief Orientation to Methods. SOCoP 2012 Workshop Gary Berg-Cross SOCoP Executive Secretary Nov. 18-19 2012 NSF Stafford II facility Wilson Blvd, Ballston VA. Outline. Lightweight Methods Ontology Engineering Problems, Component and Relation Identification & Clarification - PowerPoint PPT Presentation
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Brief Orientation to Methods
SOCoP 2012 Workshop Gary Berg-Cross
SOCoP Executive SecretaryNov. 18-19 2012
NSF Stafford II facility Wilson Blvd, Ballston VA
Orientation to Semantic Methods for Workshop 2
Outline
1. Lightweight Methods2. Ontology Engineering
1. Problems, Component and Relation Identification & Clarification
2. Conceptualization Phase Systematic
organization & framing with visual expression
3. Formalization
3
Lightweight Methods & Products Choose lightweight approaches grounded by scenarios and
application needs…with real data. Low hanging fruit leverages initial vocabularies (e.g. Biomass)
and existing conceptual models to ensure that a semantics-driven infrastructure is available for use in early stages of work
Reduced entry barrier for domain scientists to contribute data
Simple parts/patterns & direct relations to data
Ecological..
Triple like parts
Constrained not totallySpecified.Grounded
Orientation to Semantic Methods for Workshop 4
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 are surface water objects (not processes?)…..
What is the scope? Not how streams flood, but 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 work
E.g. reference or include supporting vocabularies/ontologies, Terminologies are starting point, on a path to the concepts behind
what the terms mean to domain people and be relatable to “data.”
Session organizers can provide a start
Orientation to Semantic Methods for Workshop 5
Forge Consensus on Some of the Relevant Terms/ Concepts & Express
To be a quality model (& laterontology) 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) A TransportEvent has parts
TransportEvent and TransportMechanim
TransportMechanim may be Active or Passive
Osmosis is a Passive TransportMechanim
ATP is an Active TransportMechanim
Inside
Outside
Boundary
SpatialRegion
SpatialObject
Container
Controlled vocabulary suitable for OWL or CL helps
Transformed ContainedObject
Simple Ontologies Serve as Concept Model with Vocabularies
Old link http://frot.org/ontobot/ for work related to this ontology
Orientation to Semantic Methods for Workshop 6
Space namespace GEONet “Ontology” a simple vocabulary for describing physical spaces and the connections between them
"A Building is a kind of Hypsographic Feature." Hypsographic is a top-level classification from GEONet and just means something that's found on land. It goes on: "A Public Building is a kind of Building, and a Recreational Venue is a kind of Public Building."
Orientation to Semantic Methods for Workshop 7
2. Conceptualization
1. Correctly captures intuitions of domain experts as they express intended content (expressivity)
1. These statements should be understandable to humans E.g. MoreDense” is transitive(container1-salinity
MoreDense container2-salinity and transitive(container2-salinity MoreDense container3-salinity THEN….)• Formalization will make them processable by computing
systems.
2. Minimally redundant – avoid unintended synonyms
3. Reduce multiple possible meanings/ambiguity1. systems & people can recognize commonalities and
differences in the semantics of the concepts that they use.
Orientation to Semantic Methods for Workshop 8
Conceptual Pattern Example- A Schema for Motion (like Osmosis??)
S
G
onPath
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.
All paths have a start point
End point could be represented in a
coordinate system (or a changed state?)
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.
Orientation to Semantic Methods for Workshop 9
Path-name
-start object -end object
-path description-medium - surface
is part ofMotion
has part
hasPath
MovingObject
hasPath
Geo-VoCamp Patterns – Path from an infoperspective
Just OWL ClassesMotion is an OWL:Class
Light constraints
Orientation to Semantic Methods for Workshop 10
Point of Interest (POI) Pattern:Geographic information constructs, not direct representations of real entities
Some placeholdersIdeas for later analysis.
Groundable by adding data not more semantics
Orientation to Semantic Methods for Workshop 11
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 Ontology1. 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 relations3. Link concepts via other Relations needed for a domain:
1. ‘precedes’, ‘follows’, ‘contains’, ‘isSubEventOf’, ‘phaseOf’, ‘involves’, ‘usesTool’, ‘hasResult’, ‘has Action’ and ‘hasPresence’
3. Discuss constraints that characterize key concepts and their relations
1. ActiveTransportMechanism may not be transporting anything (broken, inactive or blocked transportMchanism idea)
2. FlowsInto relation is transitiveAdd concepts & relations & individuals to the level of detail necessary to satisfy
your purposes. All these will provide commitments to be expressed in an ontological language
Orientation to Semantic Methods for Workshop 12
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…..
Orientation to Semantic Methods for Workshop
13
Align & Compose New ODP from Old: Semantic Trajectory
•Preserves axioms from other ODPs•Adds concepts
Grounded 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……
ODPs are relatively autonomous but conceivably composable with other schemas.E.g. compose a Semantic Trajectory Pattern fromTrajectories/spatial paths/segments
Point Of Interest (POI)- observation area etc.
Orientation to Semantic Methods for Workshop 14
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.
Orientation to Semantic Methods for Workshop 15
3. Formally Committing to our Conceptualization with Axiomatized Semantics
1. Formal –can be represented/put into a form amenable to automated processing [formal language] Ontology forms are implemented in languages like
OWL Where we have concepts with axioms defined on such
concept vocabularies1. Sufficiently axiomatized – include detailed constraining
descriptions, such as transitivity, as axioms (not just text descriptions)
1. Rigorous – stands up to rational analysis
2. Distinguish which concepts have instances 1. Named classes can (potentially) have instances
Orientation to Semantic Methods for Workshop 16
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/SimplePartWhole/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 classrdfs: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 property, using owl:onProperty.
Backup
Orientation to Semantic Methods for Workshop 17
ODPs of Semantic Trajectory Extension- Hydro Observations as Annotations
Environmental Observations fit into this schema.
Fixes may be hydrometric feature observations & at some PoI (and offset Fix) for some point or period of time denoting important activities and/or decision points, that researchers may be interested in labeling and classifying. Observations including timeseries
sets might be applied to something like streamflow or temperature plots or a pollution plume
You may query Schema : “Show locations within Gulf of
Mexico fishing area with colored dissolved organic matter”
Hydro Var & attr/data or
value
HydroObject or moving
device
HydroObs/Device
18
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