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

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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

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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 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

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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."

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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.

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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.

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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

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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

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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 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

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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…..

Orientation to Semantic Methods for Workshop

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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.

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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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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

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