Brian Panulla
Director, Extreme Events Laboratory, Pennsylvania State University
October 6
Presentation http://2009.highedweb.org/presentations/TPR9.pdf
or local copy An Argument For Semantics
The quest for a smarter web
What is semantic web and why would I want one.
The “O” word – ontology
Using SW technology today
New w3c
RDF, RDF Schema, OWL
Each build on one another, but all are fundamentally RDF
Implied Meaning
What we have now needs a human to process it.
We want to markup for machines
meaning of symbols
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words usage, connotation
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images symbolism
become real useful when shared
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between individuals
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within a community or culture
Is this more catherderal thinking?
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Top-down ivory tower approach has led to out current network of walled gardens of data
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Could some of out data be more open?
Why can’t we pull non-sensitive data from an open, central source?
How many Web applications have local copies of:
States, countries, campuses, majors, courses?
Why are we maintaining them?
Separation of concerns
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smarter data is driving new levels of separation of concerns
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content, presentation, behavior, and rules
Is HTML dead? No
The SW infrastructure
a parallel information architecture design pattern for smarter applications
web content, pages and sites do not
roadmap to smart data
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entities as resources
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specifying relationships
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drawing inferences
Entities as Resources
Locally “IST” refers to at least 6 entities (for Penn State)
how do we identify entities
differentiating between conceptual entities creates the need for an identifier
indefinite article A college of IST
Convention allows us to simplify integration of data across systems
Convention is implicit symantics
In the absence of a good candidate key, each organization usually make an ad hoc identifiers.
We have a handy tool to globally identify – it’s URI
Normally they are unique, but that can be overwritten
RDF
RDF is the language that gives us resources, specifies properties
RDF can be used to specify is-a, is-a-member-of,
It stores as triples: subject, predicate, object
RDF schemas
dont give meaning
Ontology gives meaning
a formal ontology is a representation of a true ontology in some sor of communicable format
“its the next level up from schema”
OWL features
classes, properties, individuals
Data can be inferred or derived with owl/rdf with symantics.
Ex: if a is near b and c is near b then a is near c.
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