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Semantics
• Semantics – ancient Greek for meaning σημαίνω – I signal, sign,
show
• Semantics has become a buzzword or even a fuzzword
• Example from a book about Eclipse:
– “We’ll use the same mechanisms to navigate semantic errors (…)
that we use to navigate compile errors.”
– (failing tests) – semantic error is less precise than “failing tests”
– a fuzzword in this case
• Oxford English Dictionary: 2. a. Relating to signification or meaning.
(as adjective)
© 2005-2006 The ATHENA Consortium.
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Semantics and Definitions
• Standard way to communicate meaning is by definition
• definition: “Verbal description of a concept, permitting its
differentiation from other concepts within a system of concepts.”
– International Standard ISO 1087, Terminology – Vocabulary, 1990
• The Semantic Web is about formalizing your definitions
“the Semantic Web, as envisioned by Tim Berners-Lee and many
others since, is a logical extension of the current Web that
enables explicit [machine-processable] representations of term
meanings [concepts]”
– Frankel, David; Hayes, Pat; Kendall, Elisa; McGuinness, Deborah: MDA
Journal July 2004
© 2005-2006 The ATHENA Consortium.
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Formality Spectrum: informal
SAPterm
WordNet
Informal
© 2005-2006 The ATHENA Consortium.
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Formality Spectrum: formal
"An ontology is an explicit and
formal specification of a shared
conceptualization"
Ontology, e.g, OWL ontology
SAPterm
Informal
WordNet
Formal
Every tomato is red.
for all x ( tomato (x) implies red (x) )
© 2005-2006 The ATHENA Consortium.
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