#relative: rule-36,rule-29,rule-17,
rule-90,rule-103;
/* rules connected with #rule-81 */
The RELATIVE of a rule is one or several
other rules that have almost the same
conditions, and is used to increase searching
speed. This item may be got automatically by
the system.
3. REASONNING METHODS USED IN MCGES-GIE
In accordance with the three levels of
knowledge, a complete inference procedure of
MCGES-GIE is composed of several operations
in three levels.
3.1 Basic inference
We can use the knowledge in the first level
to match values of factors got from MCGIS , and
grade the factors. The results of basic
inference are the classes of basic
geographical factors of objects.
3.2 Medium inference
There are two goals in this step, one is to
calculate attribute values of integrated
geographical factors, another is to classify
the integrated geographical factors based on
the conclusions of the basic inference and
the medium knowledge (rules).
Now we can get a great deal of remote sensing
data,but much less survey data.Remote sensing
data may be considered as a kind output of
geographical phenomena, and those relatively
less survey data may be considered as the
really geographical features. Fuzzy
mathematics is a suitable tool to distinguish
successive varibles and can be conveniently
used to build geographical classification
model with remote sensing data.For example,if
we have got MSS-4,5,6 and 7 image data of the
same district, we can construct a fuzzy
function to classify landuse types in this
district according to the image data of four
bands,
object set: X={x ! x'=(x1,x2,x3,x4)}
where x1,x2,x3,and x4 represent grey values
of MSS-4,5,6,and 7.
fuzzy classification model is
AizAilfl Ai2 f] Ai3 f] Ai4 (1)
where Aij is normal fuzzy set,
jurisdiction function of Ai on X is
Ai(x)= min Aij(xj) =
I<=j¢<=4 ^"
xj-aij \2
exp [: max —————— ) J (2)
1<=j<=4 bij
where aij=Exij, bj= dDxij;
izl, 2,..., n are type code;
j=1, 2, 3, 4 are band code.
then we have following classification
267
formula,
a. A (x) max min Aij (xj)-
ek 1<=i<=4 1<=j<=4 ~
xij-aij \2
bn. Je
1<=i<=n 1<=j<=4 bij
4
b. (Ai,B)= A (Aij,Bj)= min (Aij,Bj) (4)
ths j=1 " - 1<=j<=4
if let ej=Exj, dj=ADx, xj € Bj,
ew ^
4
and B- f| Bj is the fuzzy subset that need
be classified, then we have,
(Ak,B)= max (Ai,B) -
"e deje ^
aij-ej à
0.5* | 1texpi- min max ME (5)
1<=i<=4 1<=j<=4\ bij+dj
and B can be considered as type k.
Grey system theory can forcast the developing
trendency of varibles with relatively less
known condition, and can describe the
unbalanced relationship between main varible
and subordinated varibles. Helped by grey
system theory, we can build geographical grey
model based on remote sensing data and survey
data.A general Grey Model (GM)may be shown as
GM(n, h) , which is a n factorial, h varibles
differential equation,its expression is,
n,Q) h-t,, CO T
d e + Qu M AS t+ Qa x,
= bı y C " b, x ++ Du vm (6)
After getting integrated geographical factor
values,using medium knowledge and conclusions
of basic inference to match with them, we can
gain the geographical classification results,
which will be used in advanced inference.
3.3 Advanced inference
Based on the conclusions of the basic and
medium inference and the advanced knowledge
(rules) ,we can gain the decision measures or
divisions and planning scheme on a certain
geographical problem, which is the last step
in the inference.
Because most of geographical inference are
shown as under certain conditions to gain
certain results,in this step,MCGES-GIE adopts
following production strategy in reasonning:
RULE : if A then B
PREMISE : A is true
CONCLUSION : B is true
EFFECTIVENESS: possibility
The advanced inference uses Bayes theorem and
fuzzy logic to reason. If we record the
probability of conclusion with evidence
existing as P(CiE) ,then Bayes theorem may be
show as,