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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
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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 • Conceptualization Phase • Systematic organization & framing with visual expression • Formalization Orientation to Semantic Methods for Workshop
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 Triple like parts Simple parts/patterns & direct relations to data Constrained not totally Specified. Grounded Ecological..
Step 1:Acquire Scoped Domain Knowledge & Vocabulary Principle: Clarify & Indentify Problem, Components & Relations • Identify scope: We prefer working from scenario examples with potential data tohelp 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
Forge Consensus on Some of the Relevant Terms/ Concepts & Express Transformed Contained Object Outside To be a quality model (& later ontology) we should be able to make meaningful statements about what exists in our focused domain/topic and • establishconsensusabout 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 Container SpatialRegion Boundary SpatialObject Controlled vocabulary suitable for OWL or CL helps Orientation to Semantic Methods for Workshop
Simple Ontologies Serve as Concept Model with Vocabularies Space namespace GEONet “Ontology” a simple vocabulary for describing physical spaces and the connections between them Old link http://frot.org/ontobot/ for work related to this ontology "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
2. Conceptualization • Correctly captures intuitions of domain experts as they express intended content (expressivity) • 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. • Minimally redundant – avoid unintended synonyms • Reduce multiple possible meanings/ambiguity • systems & people can recognize commonalities and differences in the semantics of the concepts that they use. Orientation to Semantic Methods for Workshop
Conceptual Pattern Example- A Schema for Motion (like Osmosis??) 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 End point could be represented in a coordinate system (or a changed state?) onPath S 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
Just OWL Classes Motion is an OWL:Class Geo-VoCamp Patterns – Path from an infoperspective Motion is part of Path -name -start object • end object • path description -medium - surface hasPath hasPath Moving Object has part Light constraints Orientation to Semantic Methods for Workshop
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. Orientation to Semantic Methods for Workshop
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 • Identifying & defining the domain's principal concrete concepts & building a concept base (Objects ->Classes) • Identifying the relationships among the concepts • Arrange in taxonomical class hierarchy(s) • Clarify IsA hierarchies and part-whole relations • Link concepts via other Relations needed for a domain: • ‘precedes’, ‘follows’, ‘contains’, ‘isSubEventOf’, ‘phaseOf’, ‘involves’, ‘usesTool’, ‘hasResult’, ‘has Action’ and ‘hasPresence’ • Discuss constraints that characterize key concepts and their relations • ActiveTransportMechanism may not be transporting anything (broken, inactive or blocked transportMchanism idea) • FlowsInto relation is transitive Add 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
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
Align & Compose New ODP from Old: Semantic Trajectory ODPs are relatively autonomous but conceivably composable with other schemas. E.g. compose a Semantic Trajectory Pattern from Trajectories/spatial paths/segments Point Of Interest (POI)- observation area etc. • 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…… Orientation to Semantic Methods for Workshop
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
3. Formally Committing to our Conceptualization with Axiomatized Semantics • 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 vocabularies • Sufficiently axiomatized – include detailed constraining descriptions, such as transitivity, as axioms (not just text descriptions) • Rigorous – stands up to rational analysis • Distinguish which concepts have instances • Named classes can (potentially) have instances Orientation to Semantic Methods for Workshop
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 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 ] . Motion / Path RDF/ontology in Turtle (TTL):(Terse RDF Triple Language – uses a . , ;]) A restriction class should have exactly one triple linking the restriction to a particular property, using owl:onProperty. Orientation to Semantic Methods for Workshop
Backup Orientation to Semantic Methods for Workshop
ODPs of Semantic Trajectory Extension- Hydro Observations as Annotations Hydro Obs/Device HydroVar & attr/data or value • 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 Object or moving device