Operationalizing Declarative and Procedural Knowledge a b e n c - - PowerPoint PPT Presentation

operationalizing declarative and procedural knowledge
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Operationalizing Declarative and Procedural Knowledge a b e n c - - PowerPoint PPT Presentation

Operationalizing Declarative and Procedural Knowledge a b e n c h m a r k o n L o g i c P r o g r a m m i n g P e t r i N e t s ( L P P N s ) C A U S A L 2 0 2 0 Wo r k s h o p o n C


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SLIDE 1

Operationalizing Declarative

C A U S A L 2 2 Wo r k s h

  • p
  • n

C a u s a l R e a s

  • n

i n g a n d E x p l a n a t i

  • n

i n L

  • g

i c P r

  • g

r a m m i n g @ I C L P 2 2

G i

  • v

a n n i S i l e n

  • g

. s i l e n

  • @u

v a . n l I n f

  • r

m a t i c s I n s t i t u t e , U n i v e r s i t y

  • f

A m s t e r d a m a b e n c h m a r k

  • n

L

  • g

i c P r

  • g

r a m m i n g P e t r i N e t s ( L P P N s )

1 9 S e p t e m b e r 2 2

and Procedural Knowledge

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SLIDE 2
  • R

e g u l a t i

  • n

s c

  • n

c e r n s y s t e ms

  • f

n

  • r

ms , t h a t i n a b s t r a c t , i n a f i x e d p

  • i

n t i n t i m e , m a y b e a p p r

  • a

c h e d a t e m p

  • r

a l l y .

  • H
  • w

e v e r , w h e n a p p l i e d , r e g u l a t i

  • n

s d e a l w i t h a c

  • n

t i n u

  • u

s f l

  • w
  • f

e v e n t s .

  • P

r

  • t
  • t

y p i c a l e n c

  • u

n t e r : l e g a l c a s e s .

  • M
  • r

e g e n e r a l b u t s i m i l a r p r

  • b

l e m : n a r r a t i v e s , s t

  • r

i e s .

P r

  • b

l e m : r e a s

  • n

i n g w i t h c a s e s

slide-3
SLIDE 3

Wh i l e J

  • h

n w a s w a l k i n g h i s d

  • g

, t h e d

  • g

a t e P a u l ’ s f l

  • w

e r s .

P r

  • b

l e m : r e a s

  • n

i n g w i t h c a s e s

slide-4
SLIDE 4

Wh i l e J

  • h

n w a s w a l k i n g h i s d

  • g

, t h e d

  • g

a t e P a u l ’ s f l

  • w

e r s .

P r

  • b

l e m : r e a s

  • n

i n g w i t h c a s e s

H

  • w

t

  • e

n t a i l t h a t J

  • h

n i s r e s p

  • n

s i b l e t

  • p

a y P a u l ?

slide-5
SLIDE 5

Wh i l e J

  • h

n w a s w a l k i n g h i s d

  • g

, t h e d

  • g

a t e P a u l ’ s f l

  • w

e r s .

P r

  • b

l e m : r e a s

  • n

i n g w i t h c a s e s

T h e

  • w

n e r

  • f

a n a n i m a l h a s t

  • p

a y f

  • r

t h e d a m a g e s i t p r

  • d

u c e s .

( e x a mp l e

  • f

u n d e r l y i n g n

  • r

m) H

  • w

t

  • e

n t a i l t h a t J

  • h

n i s r e s p

  • n

s i b l e t

  • p

a y P a u l ?

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SLIDE 6

Wh i l e J

  • h

n w a s w a l k i n g h i s d

  • g

, t h e d

  • g

a t e P a u l ’ s f l

  • w

e r s .

P r

  • b

l e m : r e a s

  • n

i n g w i t h c a s e s

T h e

  • w

n e r

  • f

a n a n i m a l h a s t

  • p

a y f

  • r

t h e d a m a g e s i t p r

  • d

u c e s .

A c

  • n

c e p t u a l g a p e x i s t s b e t w e e n t h e c

  • n

c r e t e d

  • ma

i n a n d t h e l e g a l a b s t r a c t i

  • n

t h a t a p p l i e s

  • n

i t . ( e x a mp l e

  • f

u n d e r l y i n g n

  • r

m) H

  • w

t

  • e

n t a i l t h a t J

  • h

n i s r e s p

  • n

s i b l e t

  • p

a y P a u l ?

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SLIDE 7

Wh i l e J

  • h

n w a s w a l k i n g h i s d

  • g

, t h e d

  • g

a t e P a u l ’ s f l

  • w

e r s .

T h e

  • w

n e r

  • f

a n a n i ma l h a s t

  • p

a y f

  • r

t h e d a ma g e s i t p r

  • d

u c e s .

d

  • g

s a r e a n i ma l s e a t i n g a n

  • b

j e c t d e s t r

  • y

s t h e

  • b

j e c t d e s t r u c t i

  • n

i s d a ma g e f l

  • w

e r s a r e

  • b

j e c t s

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SLIDE 8

Wh i l e J

  • h

n w a s w a l k i n g h i s d

  • g

, t h e d

  • g

a t e P a u l ’ s f l

  • w

e r s .

T h e

  • w

n e r

  • f

a n a n i ma l h a s t

  • p

a y f

  • r

t h e d a ma g e s i t p r

  • d

u c e s .

d

  • g

s a r e a n i ma l s e a t i n g a n

  • b

j e c t d e s t r

  • y

s t h e

  • b

j e c t d e s t r u c t i

  • n

i s d a ma g e f l

  • w

e r s a r e

  • b

j e c t s s

  • me

c

  • n

n e c t i

  • n

s a r e t e r mi n

  • l
  • g

i c a l ( e . g . t a x

  • n
  • mi

c a l r e l a t i

  • n

s )

  • t

h e r p r

  • v

i d e s c a u s a l me a n i n g

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SLIDE 9

T y p e s

  • f

K n

  • w

l e d g e

  • D

e c l a r a t i v e k n

  • w

l e d g e , c

  • n

c e r n i n g

  • b

j e c t s ( p h y s i c a l , m e n t a l , i n s t i t u t i

  • n

a l ) a n d t h e i r l

  • g

i c a l r e l a t i

  • n

s h i p s — t y p i c a l l y r e i f i e d b y m e a n s

  • f

s y m b

  • l

s

  • P

r

  • c

e d u r a l k n

  • w

l e d g e , c

  • n

c e r n i n g p a t t e r n s

  • f

e v e n t s / a c t i

  • n

s , m e c h a n i s m s ,

  • r

p r

  • c

e s s e s ( i n v

  • l

v i n g

  • b

j e c t s ) —o f t e n t a c i t , i n t e r n a l i z e d

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SLIDE 10

We n e e d a n

  • t

a t i

  • n

t

  • s

p e c i f y b

  • t

h !

  • P

h y s i c a l s y s t e m s c a n b e a p p r

  • a

c h e d f r

  • m

s t e a d y s t a t e ( e q u i l i b r i u m )

  • r

t r a n s i e n t ( n

  • n
  • e

q u i l i b r i u m , d y n a m i c ) p e r s p e c t i v e s

  • S

t e a d y s t a t e s d e s c r i p t i

  • n

s

  • mi

t t r a n s i e n t c h a r a c t e r i s t i c s

e x . O h m ' s L a w . V = R * I

P e r s p e c t i v e s

  • n

M

  • d

e l l i n g

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SLIDE 11

We n e e d a n

  • t

a t i

  • n

t

  • s

p e c i f y b

  • t

h !

  • P
  • s

s i b l e a n a l

  • g

i e s :

– s

t e a d y s t a t e a p p r

  • a

c h w i t h

  • L
  • g

i c

  • D

e c l a r a t i v e p r

  • g

r a m m i n g f

  • c

u s

  • n

Wh a t

S p e c i f y i n g t r a n s i e n t s a n d s t e a d y s t a t e s

slide-12
SLIDE 12

We n e e d a n

  • t

a t i

  • n

t

  • s

p e c i f y b

  • t

h !

  • P
  • s

s i b l e a n a l

  • g

i e s :

– s

t e a d y s t a t e a p p r

  • a

c h w i t h

  • L
  • g

i c

  • D

e c l a r a t i v e p r

  • g

r a m m i n g

– t

r a n s i e n t a p p r

  • a

c h

  • P

r

  • c

e s s m

  • d

e l l i n g

  • P

r

  • c

e d u r a l p r

  • g

r a m m i n g f

  • c

u s

  • n

Wh a t

f

  • c

u s

  • n

H

  • w

S p e c i f y i n g t r a n s i e n t s a n d s t e a d y s t a t e s

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SLIDE 13

We n e e d a n

  • t

a t i

  • n

t

  • s

p e c i f y b

  • t

h !

  • P
  • s

s i b l e a n a l

  • g

i e s :

– s

t e a d y s t a t e a p p r

  • a

c h w i t h

  • L
  • g

i c

  • D

e c l a r a t i v e p r

  • g

r a m m i n g

– t

r a n s i e n t a p p r

  • a

c h

  • P

r

  • c

e s s m

  • d

e l l i n g

  • P

r

  • c

e d u r a l p r

  • g

r a m m i n g f

  • c

u s

  • n

Wh a t

f

  • c

u s

  • n

H

  • w

P e t r i N e t s !

S p e c i f y i n g t r a n s i e n t s a n d s t e a d y s t a t e s

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SLIDE 14

We n e e d a n

  • t

a t i

  • n

t

  • s

p e c i f y b

  • t

h !

f

  • c

u s

  • n

Wh a t

f

  • c

u s

  • n

H

  • w

P e t r i N e t s !

  • P
  • s

s i b l e a n a l

  • g

i e s :

– s

t e a d y s t a t e a p p r

  • a

c h w i t h

  • L
  • g

i c

  • D

e c l a r a t i v e p r

  • g

r a m m i n g

– t

r a n s i e n t a p p r

  • a

c h

  • P

r

  • c

e s s m

  • d

e l i n g

  • P

r

  • c

e d u r a l p r

  • g

r a m m i n g

A n s w e r S e t P r

  • g

r a m m i n g

S p e c i f y i n g t r a n s i e n t s a n d s t e a d y s t a t e s

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SLIDE 15

f

  • c

u s

  • n

Wh a t

f

  • c

u s

  • n

H

  • w

P e t r i N e t s !

  • P
  • s

s i b l e a n a l

  • g

i e s :

– s

t e a d y s t a t e a p p r

  • a

c h w i t h

  • L
  • g

i c

  • D

e c l a r a t i v e p r

  • g

r a m m i n g

– t

r a n s i e n t a p p r

  • a

c h

  • P

r

  • c

e s s m

  • d

e l i n g

  • P

r

  • c

e d u r a l p r

  • g

r a m m i n g

A n s w e r S e t P r

  • g

r a m m i n g

L P P N s

l

  • g

i c p r

  • g

r a m m i n g p e t r i n e t s

S p e c i f y i n g t r a n s i e n t s a n d s t e a d y s t a t e s

+ =

slide-16
SLIDE 16

L

  • g

i c P r

  • g

r a m m i n g P e t r i N e t s

slide-17
SLIDE 17

L

  • g

i c P r

  • g

r a m m i n g P e t r i N e t ( L P P N )

  • A

n L P P N c

  • n

s i s t s

  • f

t h r e e c

  • m

p

  • n

e n t s :

– a

p r

  • c

e d u r a l n e t ( p l a c e s , t r a n s i t i

  • n

s )

– a

d e c l a r a t i v e n e t f

  • r

p l a c e s

– a

d e c l a r a t i v e n e t f

  • r

t r a n s i t i

  • n

s

causal mechanisms logical dependencies between objects logical dependencies between events

slide-18
SLIDE 18

P r

  • c

e d u r a l L P P N

( s a m e a s C

  • n

d i t i

  • n

/ E v e n t P N ) t r a n s i t i

  • n

p l a c e

  • P

e t r i n e t : b i p a r t i t e d i r e c t e d g r a p h m a d e

  • f

p l a c e s ( c i r c l e s ) a n d t r a n s i t i

  • n

s ( b

  • x

e s ) .

slide-19
SLIDE 19

t r a n s i t i

  • n

p l a c e

t

  • k

e n

P r

  • c

e d u r a l L P P N

( s a m e a s C

  • n

d i t i

  • n

/ E v e n t P N )

  • t
  • k

e n s m a y

  • c

c u p y p l a c e s .

slide-20
SLIDE 20
  • E

x e c u t i

  • n

s e m a n t i c s ( t

  • k

e n g a m e ) : i f a n y

  • f

i t s i n p u t p l a c e s i s n

  • t
  • c

c u p i e d , t h e t r a n s i t i

  • n

i s d i s a b l e d . I t c a n n

  • t

f i r e .

P r

  • c

e d u r a l L P P N

( s a m e a s C

  • n

d i t i

  • n

/ E v e n t P N )

d i s a b l e d

slide-21
SLIDE 21
  • E

x e c u t i

  • n

s e m a n t i c s ( t

  • k

e n g a m e ) : i f a l l

  • f

i t s i n p u t p l a c e s a r e

  • c

c u p i e d , t h e t r a n s i t i

  • n

i s e n a b l e d . I t c a n f i r e .

P r

  • c

e d u r a l L P P N

( s a m e a s C

  • n

d i t i

  • n

/ E v e n t P N )

e n a b l e d

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SLIDE 22
  • E

x e c u t i

  • n

s e m a n t i c s ( t

  • k

e n g a m e ) : w h e n t h e t r a n s i t i

  • n

f i r e s i t w i l l c

  • n

s u m e t

  • k

e n s f r

  • m

t h e i n p u t p l a c e s .

P r

  • c

e d u r a l L P P N

( s a m e a s C

  • n

d i t i

  • n

/ E v e n t P N )

f i r i n g

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SLIDE 23
  • E

x e c u t i

  • n

s e m a n t i c s ( t

  • k

e n g a m e ) : . . . a n d p r

  • d

u c e t

  • k

e n s i n t h e

  • u

t p u t p l a c e s .

P r

  • c

e d u r a l L P P N

( s a m e a s C

  • n

d i t i

  • n

/ E v e n t P N )

f i r i n g

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SLIDE 24
  • F
  • r
  • u

r p u r p

  • s

e s , t h i s m a p s t

  • a

r e a c t i v e r u l e ( E C A ) :

P r

  • c

e d u r a l L P P N

( s a m e a s C

  • n

d i t i

  • n

/ E v e n t P N ) #t1 : p1, p2 => -p1, -p2, +p3.

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SLIDE 25
  • C
  • n

s t r u c t e d f r

  • m

t h e A S P p r

  • g

r a m : p6 :- p4, p5. p5.

D e c l a r a t i v e L P P N f

  • r

p l a c e s

slide-26
SLIDE 26
  • E

q u i v a l e n t t

  • p6 :- p4, p5.

p5.

D e c l a r a t i v e L P P N f

  • r

p l a c e s

e n t a i l s p5.

a n s w e r s e t

slide-27
SLIDE 27
  • E

q u i v a l e n t t

  • p6 :- p4, p5.
  • p4. p5.

D e c l a r a t i v e L P P N f

  • r

p l a c e s

slide-28
SLIDE 28
  • E

q u i v a l e n t t

  • p6 :- p4, p5.
  • p4. p5.

D e c l a r a t i v e L P P N f

  • r

p l a c e s

  • p4. p5. p6.

e n t a i l s

a n s w e r s e t

slide-29
SLIDE 29
  • E

q u i v a l e n t t

  • #t3 :- #t2, p9.

#t4 :- #t2, p8. #t2. p7. p8.

D e c l a r a t i v e L P P N f

  • r

t r a n s i t i

  • n

s

slide-30
SLIDE 30
  • E

q u i v a l e n t t

  • #t3 :- #t2, p9.

#t4 :- #t2, p8. #t2. p7. p8.

D e c l a r a t i v e L P P N f

  • r

t r a n s i t i

  • n

s

#t2. p7. p8. #t4. e n t a i l s

a n s w e r s e t p r

  • p

a g a t i

  • n
slide-31
SLIDE 31
  • E

q u i v a l e n t t

  • #t3 :- #t2, p9.

#t4 :- #t2, p8. #t2. p7. p8.

D e c l a r a t i v e L P P N f

  • r

t r a n s i t i

  • n

s

#t2. p7. p8. #t4. p r

  • d

u c e s p11. e n t a i l s

a n s w e r s e t

slide-32
SLIDE 32
  • dog. flower. dog-walking. #dog-eats-flower.

animal :- dog.

  • bject :- flower.

damage :- destruction. #eat-object :- #dog-eats-flower. #destroy-object :- #eat-object. #destroy-object : object => -object, +destruction.

w h i l e J

  • h

n w a s w a l k i n g h i s d

  • g

, t h e d

  • g

a t e P a u l ’ s f l

  • w

e r s ( “ s t

  • r

y ” ) c a u s a l m e c h a n i s m s l

  • g

i c a l d e p e n d e n c i e s a t l e v e l

  • f

e v e n t s l

  • g

i c a l d e p e n d e n c i e s a t l e v e l

  • f
  • b

j e c t s

I n i t i a l e x a m p l e ( p a r t i a l m

  • d

e l )

slide-33
SLIDE 33

E x e c u t i

  • n

s e m a n t i c s

slide-34
SLIDE 34

E x e c u t i

  • n

s e m a n t i c s

  • T

h e p a p e r p r e s e n t s t w

  • s

e m a n t i c s :

– a

d e n

  • t

a t i

  • n

a l s e ma n t i c s , m a p p i n g c a u s a l m e c h a n i s m s t

  • A

S P u s i n g E v e n t C a l c u l u s → ASP solver

slide-35
SLIDE 35

E x e c u t i

  • n

s e m a n t i c s

  • T

h e p a p e r p r e s e n t s t w

  • s

e m a n t i c s :

– a

d e n

  • t

a t i

  • n

a l s e ma n t i c s , m a p p i n g c a u s a l m e c h a n i s m s t

  • A

S P u s i n g E v e n t C a l c u l u s

– a

h y b r i d s e ma n t i c s , c

  • n

s i s t i n g

  • f

4 s t e p s :

1 . s

  • l

v e l

  • g

i c a l d e p e n d e n c i e s

  • f
  • b

j e c t s 2 . s e l e c t

  • n

e e n a b l e d t r a n s i t i

  • n

t

  • f

i r e 3 . s

  • l

v e l

  • g

i c a l d e p e n d e n c i e s

  • f

e v e n t s 4 . e x e c u t e t h e s e l e c t e d f i r i n g u s i n g t h e P e t r i N e t

→ ASP solver → ASP solver direct computation direct computation

slide-36
SLIDE 36

E x e c u t i

  • n

s e m a n t i c s

  • T

h e p a p e r p r e s e n t s t w

  • s

e m a n t i c s :

– a

d e n

  • t

a t i

  • n

a l s e ma n t i c s , m a p p i n g c a u s a l m e c h a n i s m s t

  • A

S P u s i n g E v e n t C a l c u l u s

– a

h y b r i d s e ma n t i c s , c

  • n

s i s t i n g

  • f

4 s t e p s :

1 . s

  • l

v e l

  • g

i c a l d e p e n d e n c i e s

  • f
  • b

j e c t s 2 . s e l e c t

  • n

e e n a b l e d t r a n s i t i

  • n

t

  • f

i r e 3 . s

  • l

v e l

  • g

i c a l d e p e n d e n c i e s

  • f

e v e n t s 4 . e x e c u t e t h e s e l e c t e d f i r i n g u s i n g t h e P e t r i N e t

→ ASP solver → ASP solver direct computation direct computation

Q u e s t i

  • n

: h

  • w

t h e y c

  • mp

a r e i n t e r ms

  • f

c

  • mp

u t a t i

  • n

a l p e r f

  • r

ma n c e ?

slide-37
SLIDE 37

E x e c u t i

  • n

s e m a n t i c s

  • T

h e p a p e r p r e s e n t s t w

  • s

e m a n t i c s :

– a

d e n

  • t

a t i

  • n

a l s e ma n t i c s , m a p p i n g c a u s a l m e c h a n i s m s t

  • A

S P u s i n g E v e n t C a l c u l u s

– a

h y b r i d s e ma n t i c s , c

  • n

s i s t i n g

  • f

4 s t e p s :

1 . s

  • l

v e l

  • g

i c a l d e p e n d e n c i e s

  • f
  • b

j e c t s 2 . s e l e c t

  • n

e e n a b l e d t r a n s i t i

  • n

t

  • f

i r e 3 . s

  • l

v e l

  • g

i c a l d e p e n d e n c i e s

  • f

e v e n t s 4 . e x e c u t e t h e s e l e c t e d f i r i n g u s i n g t h e P e t r i N e t

→ ASP solver → ASP solver direct computation direct computation

Q u e s t i

  • n

: h

  • w

t h e y c

  • mp

a r e i n t e r ms

  • f

c

  • mp

u t a t i

  • n

a l p e r f

  • r

ma n c e ? Wh y t h e y s h

  • u

l d d i f f e r ?

slide-38
SLIDE 38

E x p e r i m e n t

slide-39
SLIDE 39

E x p e r i m e n t

  • We

c

  • n

s i d e r e d t w

  • b

a s i c r e i t e r a b l e s t r u c t u r e s a t p r

  • c

e s s l e v e l :

– S

e r i a l c

  • m

p

  • s

i t i

  • n

( d e t e r m i n i s t i c )

– F

  • r

k i n g ( n

  • n
  • d

e t e r m i n i s t i c )

  • We

e x e c u t e d a b e n c h m a r k

  • n

n e t s

  • b

t a i n e d b y i t e r a t i n g t h e s e b a s i c s t r u c t u r e s , w i t h

  • n

e t

  • k

e n i n t h e i n i t i a l p l a c e

– f

  • r

N i t e r a t i

  • n

s = 1 , 1 1 , … , 9 1 ( s e r i a l )

– f

  • r

N i t e r a t i

  • n

s = 1 , 2 , … , 1 ( f

  • r

k i n g )

C

  • d

e a v a i l a b l e a t h t t p : / / g i t h u b . c

  • m

/ s 1 l 3 n / p y p n e u

slide-40
SLIDE 40

R e s u l t s

S e r i a l c

  • m

p

  • s

i t i

  • n

Linear scale Log scale

time (ms)

slide-41
SLIDE 41

R e s u l t s

F

  • r

k i n g c

  • m

p

  • s

i t i

  • n

Log scale Linear scale

time (ms)

slide-42
SLIDE 42

Wh y t h i s d i f f e r e n c e ? ( i n t u i t i

  • n

)

slide-43
SLIDE 43

D e n

  • t

a t i

  • n

a l s e m a n t i c s : M

  • d

e l e x e c u t i

  • n

a s s e a r c h

  • S

i t u a t i

  • n

C a l c u l u s , E v e n t C a l c u l u s , F l u e n t C a l c u l u s a l l r e l y

  • n

s

  • m

e f

  • r

m

  • f

t i m e s t a m p .

  • C

a u s a l m e c h a n i s m s a r e m a p p e d t

  • l
  • g

i c a l d e p e n d e n c e s b e t w e e n t i m e s t a m p e d s n a p s h

  • t

s C a u s a t i

  • n

i n m

  • d

e l = > L

  • g

i c a l c

  • n

s t r a i n t s

slide-44
SLIDE 44
  • P

e t r i n e t s d

  • n
  • t

r e q u i r e t

  • r

e i f y t h e g l

  • b

a l s t a t e t

  • p

e r f

  • r

m e x e c u t i

  • n

.

  • T

h e y a r e d i r e c t l y m a p p a b l e t

  • i

n d i v i d u a l i n s t r u c t i

  • n

s i n i m p e r a t i v e p r

  • g

r a m s , t h e y u t i l i z e s

  • m

e ( l

  • c

a l ) i n p u t t

  • p

r

  • d

u c e s

  • m

e ( l

  • c

a l )

  • u

t p u t . C a u s a t i

  • n

i n m

  • d

e l = > C

  • m

p u t a t i

  • n

a l c a u s a t i

  • n

H y b r i d s e m a n t i c s : M

  • d

e l e x e c u t i

  • n

a s e x e c u t i

  • n
slide-45
SLIDE 45

C

  • n

c l u s i

  • n
  • T

h e p a p e r p r e s e n t s a n e m p i r i c a l e x p e r i m e n t w i t h L P P N s , a l

  • g

i c p r

  • g

r a m m i n g

  • b

a s e d e x t e n s i

  • n
  • f

P e t r i N e t s .

  • L

P P N s w e r e i n t r

  • d

u c e d w i t h a p r a c t i c a l g

  • a

l : a v i s u a l m

  • d

e l l i n g n

  • t

a t i

  • n

, r e l a t i v e l y s i m p l e f

  • r

n

  • n
  • e

x p e r t s , h a n d l i n g d e c l a r a t i v e a n d p r

  • c

e d u r a l a s p e c t s

  • f

t h e t a r g e t d

  • m

a i n .

  • H

e r e t h e f

  • c

u s h a s b e e n p u t

  • n

t h e i r c

  • m

p u t a t i

  • n

a l p r

  • p

e r t i e s , s h

  • w

i n g t h a t ma i n t a i n i n g t h e t w

  • l

e v e l s s e p a r a t e d h a s t h e p

  • t

e n t i a l t

  • b

r i n g b e t t e r p e r f

  • r

ma n c e s . T h e b e n c h m a r k n e e d s t

  • b

e e x t e n d e d .

slide-46
SLIDE 46

C

  • n

c l u s i

  • n
  • T

h e p a p e r p r e s e n t s a n e m p i r i c a l e x p e r i m e n t w i t h L P P N s , a l

  • g

i c p r

  • g

r a m m i n g

  • b

a s e d e x t e n s i

  • n
  • f

P e t r i N e t s .

  • L

P P N s w e r e i n t r

  • d

u c e d w i t h a p r a c t i c a l g

  • a

l : a v i s u a l m

  • d

e l l i n g n

  • t

a t i

  • n

, r e l a t i v e l y s i m p l e f

  • r

n

  • n
  • e

x p e r t s , h a n d l i n g d e c l a r a t i v e a n d p r

  • c

e d u r a l a s p e c t s

  • f

t h e t a r g e t d

  • m

a i n .

  • H

e r e t h e f

  • c

u s h a s b e e n p u t

  • n

t h e i r c

  • m

p u t a t i

  • n

a l p r

  • p

e r t i e s , s h

  • w

i n g t h a t ma i n t a i n i n g t h e t w

  • l

e v e l s s e p a r a t e d h a s t h e p

  • t

e n t i a l t

  • b

r i n g b e t t e r p e r f

  • r

ma n c e s . T h e b e n c h m a r k n e e d s t

  • b

e e x t e n d e d .

  • F

u t u r e d e v e l

  • p

m e n t s : e x t e n s i

  • n

t

  • p

r e d i c a t e l

  • g

i c ,

  • p

t i m i z a t i

  • n
  • f

e x e c u t i

  • n

m

  • d

e l , “ c a n

  • n

i c ” m

  • d

e l s