1. Frame systems and semantic networks
11주 강의
Frame systems and semantic networks

2. Syntax and semantics of semantic networks
subset
Cats  Mammals
∀x Cats(x) => Mammal(x)
∀x Bird(x) => Canfly(x)

3. Link types Subset A  B A⊂B Cats⊂Mammals Member A  B A∈B Bill∈Cats
R Age
A  B R(A,B) Bill  12

4. Link Types R’ legs’ AB ∀x x∈A => R(x,B) Birds 2 R’’
AB ∀x ∃y x∈A => y∈B & R(x,y)
parents’’
Birds Birds

5. Inheritance with exceptions
포유류는 다리가 4개지만 박쥐와 사람은 다리가 두 개이다.
R’ :: A must have an R’ relation to B unless there is some intervening A’ for which Rel(R’,A’,B’)
 B is a default value for the R relation for members of A

6. 정의
∀r,x,b Holds(r,x,b)  Val(r,x,b) v (∃p x∈p & Rel(r,p,b) & ~InterveningRel(x,p,r))
∀x,p,r InterveningRel(x,p,r) 
∃i Intervening(x,i,p) & ∃b’ Rel(r,i,b’)
∀a,i,p Intervening(x,I,p)  (x∈I) & (i ⊂ p)

7. Multiple inheritance
An object can belong to more than one category and can therefore inherit properties along several paths
Monotonic :::
KB├ P then (KB & S) ├ P
Non-monotonic
closed world assumption
modal logic, default logic

8. 숙제
10.1, 10.7, 10.8