27
#VET +Complexity
h
x m
RPG=(R,A)
r
q
q
VD:
h
2
(r)?
h
2
(r)=?
R
KL
={r:left
q/q
KL}
R
h
2
(r)=kc
RPG
(r,R
KL
)
h
2
(r)
min
GT={a b R}, KL={r}
{a,b,r}
7,8
{a b R A}
8
{a b R A B}
4
{a b R A B C}
1,13
{a b R A B C
c}
9,10,11
h
2
(r
7
)=kc
RPG
(r
7
, r
16
)=3
r
5
r
13
r
6
r
4
r
1 r+9
r
7
r
2
r
10
r
8
r
3
r
11
r
16
r
14
r
12
r
15
28
h
2
(r
8
)=kc
RPG
(r
8
, r
16
)=3
h
2
(r
1
)=kc
RPG
(r
1
, r
16
)=2
h
2
(r
13
)=kc
RPG
(r
13
, r
16
)=1
h
2
(r
15
)=kc
RPG
(r
15
, r
16
)=
h
2
(r
10
)=kc
RPG
(r
10
, r
10
)=1
h
2
(r
11
)=kc
RPG
(r
11
, r
16
)=1
h
2
(r
14
)=kc
RPG
(r
14
, r
16
)=1
h
2
(r
16
)=kc
RPG
(r
16
, r
16
)=0
2. Suy diễn lùi
ùi:
al=KL
Xét f
+ -
-
+
h
(r)
VD:
GT={a b R}
{S}
12,13,14
{a b c p}
{a b m
b
p}
* Cách tính
h
3
(r)
h
3
(r)=
h
3
(left
f)=kc(GT,left)
h
3
(r)
min
Kc(GT, left)=max(GT,a)
a
left
Ch r
13
29
Kc(GT, left)=max(b,a)
b
GT
VD: GT={a b R}, KL={S}
{S}
12,13,14
{a b c p}
{a b m
b
p}
h
3
(r
12
)=kc(a b R,a h
a
)=
h
3
(r
13
)=kc(a b R,a a b C)= 2
h
3
(r
14
)=kc(a b R,a b c p)= 4
h
3
(r
6
)=kc(a b R,b h
c
)=
h
3
(r
17
)=kc(a b R,a R)= 0
h
3
(r
5
)=kc(a b R,a h
c
)=
h
3
(r
8
)=kc(a b R,b R)= 0
* Cách tính
h
4
(r)?
h
4
(r)=kc
RPG
(R
GT
, r)
h
4
(r)
min
R
GT
={r: left
q/left
GT}
VD: GT={a b R} KL={S}
{S}
12,13,14
{a b c p}
{a b m
b
p}
Tính
h
4
(r) ta có:
q/ left
TGian}
y
heuristic.
Ch r
13
Ch r
7
Ch r
8
(H ch các viên)
30
h
() =
/min XACDINH (f) = {r; left
f}
XACDINH (f)
-
-
-
-
3.4. Biểu diễn TRI THỨC bằng LOGIC vị từ và SUY DIỄN
r
i
P
1
P
2
P
n
P
i
SS(UV,XZ)
2.SS(UV,XY)
SS(UV,ST)
SS(ST,XY)
3.SS(XY,UV)
SS(XZ,UV)
Thang(X,Y,Z)
4.SS(XY,UV)
Thang(X,Y,Z)
SS(UV,XZ)
SS(XY,UV)
SS(UV,XY)
SS(XY,UV)
SS(VU,YX)
GT:
KL { SS (PS, BC)
Control
mechanisms
Explicit
Implici t
A
P
Q
B
C
I
J
31
B
'
1
: TG
0
= GT
THOA = {(r
1
,
1
), (r
1
,
2
), (r
1
,
3
), (r
1
,
4
)}
1
= {A/X; B/Y; C/Z; P/U; Q/V}
2
= {C/X; Q/Y; P/Z; E/U; J/V}
3
=
4
=
1
,
1
)
TG
1
= TG
0
{SS (UV, YZ),
1
} = TG
0
{SS (PQ, BC)}
B
'
2
: TG
1
=
THOA = {(r
1
,
2
), (r
1
,
3
), (r
1
,
4
)
i
,
i
)
tron
KL SS(IJ, BC)
-
-
32
3.5. Ứng dụng các kỹ thuật suy diễn vào xây dựng hệ chuyên gia
3.5.1. Giao
3.5.1.1.
-
-
-
-
-
-
3.5.1.
k
1. a
b
c
2. d
e
f
3. c
e
g
Th
là t v
Làm vi ch y v
ph so th tri th
33
4. d
b
h
5. m
g
6. m
a
h
7. f
h
k
8. g
c
k
có:
= U{left
i
/ r:left
q
i
, q
i
KL}
= {f c g h}
={f/
(f,g)
FPG, g
KL}
xa
= {f/
g, g
KL}
TRÁI=
m
ii
left
i
1
n
}
R={r
1
m
}
r
i
: left
i
q
i
xa
={f
TRAI\
g, g
KL}
\
TRÁI={ a b c m n f g h}
\
3.5.1.3
f
34
i
: left
i
q
1
r
m
: left
m
q
m
f
F
r
1
: p
1
p
n
q
1
n
35
3.5.2.
+CSTT: Why
.
2) what if thêm r
3.5.2
P
Ph
User
G
D
MTSD
CSTT
36
-
-
nxm
T
-
3.5.2.3. Why?
Rr
:
-
-
TR L
User
G
D
MTSD
f ?
f !
WHY f?
CSTT