Information Technology Reference
In-Depth Information
(1) There is a mutation probability for each character in a string(individual), and
they are independent of each other. Randomly select several locations: x
1
x
2
···
x
l
.
(2) Create a new string
a
'=
s
1
···s
x1-1
s'
x1
s
x1+1
···s
x2-1
s'
x2
s
x2+1
···s
l
, where
s'
x1
is
randomly generated from the domain corresponding to location x
1
. And
s'
x2
···
s'
xk
are generated in the same way.
If mutation probability of each location in schema
H
is less than or equal to
p
m
, then the mutation probability of the schema
H
, whose order is supposed to be
o(H), is as follows:
p
m
)
o(H)
Ä
o(H)
1-(1-
p
m
(
p
m
<< 1/
l
)
(13.24)
13.6.5
Inversion operation
A simple inversion operation can be described through three steps:
(1) Randomly select a string from current population:
a
=
s
1
s
2
···
s
l
;
(2) Randomly select two numbers
i
' and
j'
from {01···
l
+1}, and let
i
=
};
(3) Inverse the elements between locations
min{i',j'},
j
= max{
i',j'
i
and
j,
and then a new string is
obtained:
s
1
s
2
···
s
i
s
j-1
s
j-2
···
s
i+1
s
j
···
S
l
Inversion operation can change the location of character in a
string(individual). Any kind of arrangement of characters in a string can be
obtained by using related inversion operations in turn. The main influence of
inversion operation on schema
is to randomly change the length of schema H
and the relationship among effective characters in schema H.
Besides reproduction, crossover, mutation and inversion operations, there are
other genetic operations, such as intrachromosomal duplication, elimination,
translocation and segregation.
H
13.7 Parallel Genetic Algorithm
Discrete Mandl's model-based genetic algorithm consists of the following five
parts:
(1) Chromosome representation for a given problem solving;
(2) Original species for problem solving;
