Backus Naur Grammars and Augmented Transition Networks

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Backus Naur Grammars and Augmented Transition
Networks

• By David Salley
• December 1st, 2005

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Definitions

• Cybernetics -- The study of communication and
  control processes in biological, mechanical, and
  electronic systems and the comparison of these
  processes in biological and artificial systems.
• Artificial Intelligence -- performance by a
  computer system of tasks normally requiring human
  intelligence.

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Definitions

• Expert System -- a computer program that applies
  artificial-intelligence methods to
  problem-solving
• Algorithm -- A step-by-step problem-solving
  procedure, especially an established recursive
  computational procedure for solving a problem in
  a finite number of steps.

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Famous AIs Expert Systems

• ELIZA -- a Rogerian psychotherapist
• PARRY -- the paranoid
• CASSIE reads stories
• DARPA routes supplies
• ALVINN drives a car
• DEEP BLUE plays chess
• CLIPPIE Microsoft office help

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Backus Naur Grammar

• sentence noun_phrase verb_phrase
• noun_phrase ART.ADJ. NOUN
• verb_phrase VERB ADVERB
• VERB noun_phrase

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Backus Naur Grammar

• expression expression product
• expression - product
• product
• product product product
• product / product
• factor
• factor IDENTIFIER CONSTANT
• ( expression )

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Backus Naur Grammar

• program BEGIN statement_list END
• statement_list statement_list statement
• statement IF expression THEN statement_list
  ELSE statement_list END_IF
• WHILE expression DO statement_list
  END_WHILE
• IDENTIFIER expression
• etc.

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Backus Naur Grammar

• 1. ltblazongt ltfieldgt ltcharge-listgt
• 2. ltfieldgt ltdivisiongt ltbackgroundgt AND
  ltbackgroundgt ltbackgroundgt
• 3. ltdivisiongt ltfield-divisiongt ltpartitiongt
  ltline-divisiongt ltpartitiongt
• 4. ltfield-divisiongt BARRY CHECKY VAIRY
  etc.
• 5. ltline-divisiongt PER BEND PER FESS PER
  PALE etc.
• 6. ltpartitiongt DOVETAILED EMBATTLED
  POTENTY etc.
• 7. ltbackgroundgt lttincturegt ltcolorgt
  lttreatmentgt ltmetalgt ltmetalgtlttreatmentgt ltcolorgt
  
• 8. lttincturegt ltcolorgt ltmetalgt ltfurgt
• 9. ltcolorgt AZURE GULES PURPURE VERT
  SABLE
• 10. ltmetalgt ARGENT OR
• 11. ltfurgt ERMINE VAIR PEAN etc.
• 12. lttreatmentgt FRETTY MAILLY MASONED
  etc.

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Augmented Transition Network
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Augmented Transition Network
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Questions ?
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Thank you!