Download - CS626-449: NLP, Speech and Web-Topics-in-AI
CS626-449: NLP, Speech and Web-Topics-in-AI
Pushpak BhattacharyyaCSE Dept., IIT Bombay
Lecture 35: Semantic Relations; UNL; Towards Dependency Parsing
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Web at a glance
Google indexes more than 8 billion pages
Dominated by English Large part of world is deprived of
this knowledge
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Search Engines Today
Keyword based Irrelevant results
Meaning not taken into account
Language specific No search possible across language No translation possible
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Future of the World Wide Web
WWW
User
Translationinterface
User
User
User
Translationinterface
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Features
Meaning based More relevant results
Multilingual Query in English Fetch document in Hindi Show it in English
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Machine Translation
Translate from one language to other
Two approaches Direct
One step Using Intermediate language
Two step
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Interlingua Interlingua
Intermediate language for machine translation
Step one Convert from source language text to
interlingua Step two
Produce target langauge text from interlingua
UNL : an interlingua in UNL system
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Internet for the Masses
Internet
Spanishinterface
English viewer
Hindi viewer
English interface
Spanishviewer
Hindi interfac
e
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A Semantic Graph
in: modifiera: indefinite
the: definite
student
past tense
agent
bought
objecttime
computer
new
June
modifier
The student bought a new computer in June.
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UNL representation
Ram is reading the newspaper
Representation of Knowledge
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Knowledge Representation
Ram
read
newspaper
agt obj
UNL Graph - relations
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Knowledge Representation
Ram(iof>person)
read(icl>interpret)
newspaper(icl>print_media)
UNL Graph - UWs
agt obj
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Knowledge Representation
Ram(iof>person)
read(icl>interpret)
newspaper(icl>print_media)
@entry@present@progress
@def
Ram is reading the newspaper
UNL graph - attributes
agt obj
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The boy who works here went to school
plt
agt@ entry @ past
school(icl>institution)
go(icl>move)
boy(icl>person)
work(icl>do)
here
@ entry
agt plc
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Another Example
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UNL System
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The World-wide Universal Networking Language (UNL) Project
UNL
English Russian
Japanese
Hindi
Spanish
Language independent meaning representation.
Marathi
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The UNL System: An Overview
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Universal Networking Language
Universal Words (UWs) Relations Attributes Knowledge Base
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UNL Graph
obj
agt
@ entry @ past
minister(icl>person)
forward(icl>send)
mail(icl>collection)
He(icl>person)
@def
@def
gol
He forwarded the mail to the minister.
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UNL Expression
agt (forward(icl>send).@ entry @ past, he(icl>person))
obj (forward(icl>send).@ entry @ past, minister(icl>person))
gol (forward(icl>send ).@ entry @ past, mail(icl>collection). @def)