<s>
Stochastic	B-Algorithm
diffusion	I-Algorithm
search	I-Algorithm
(	O
SDS	O
)	O
was	O
first	O
described	O
in	O
1989	O
as	O
a	O
population-based	O
,	O
pattern-matching	B-Language
algorithm	O
.	O
</s>
<s>
It	O
belongs	O
to	O
a	O
family	O
of	O
swarm	B-Architecture
intelligence	I-Architecture
and	O
naturally	O
inspired	O
search	O
and	O
optimisation	O
algorithms	O
which	O
includes	O
ant	B-Algorithm
colony	I-Algorithm
optimization	I-Algorithm
,	O
particle	B-Algorithm
swarm	I-Algorithm
optimization	I-Algorithm
and	O
genetic	B-Algorithm
algorithms	I-Algorithm
;	O
as	O
such	O
SDS	O
was	O
the	O
first	O
Swarm	B-Architecture
Intelligence	I-Architecture
metaheuristic	B-Algorithm
.	O
</s>
<s>
Unlike	O
stigmergetic	O
communication	O
employed	O
in	O
ant	B-Algorithm
colony	I-Algorithm
optimization	I-Algorithm
,	O
which	O
is	O
based	O
on	O
modification	O
of	O
the	O
physical	O
properties	O
of	O
a	O
simulated	O
environment	O
,	O
SDS	O
uses	O
a	O
form	O
of	O
direct	O
(	O
one-to-one	O
)	O
communication	O
between	O
the	O
agents	O
similar	O
to	O
the	O
tandem	O
calling	O
mechanism	O
employed	O
by	O
one	O
species	O
of	O
ants	O
,	O
Leptothorax	O
acervorum	O
.	O
</s>
<s>
As	O
a	O
result	O
of	O
the	O
diffusion	O
mechanism	O
,	O
high-quality	O
solutions	O
can	O
be	O
identified	O
from	O
clusters	B-Algorithm
of	O
agents	O
with	O
the	O
same	O
hypothesis	O
.	O
</s>
<s>
Even	O
a	O
parallel	O
exhaustive	B-Algorithm
search	I-Algorithm
through	O
the	O
restaurant	O
and	O
meal	O
combinations	O
would	O
take	O
too	O
long	O
to	O
accomplish	O
.	O
</s>
<s>
To	O
solve	O
the	O
problem	O
delegates	O
decide	O
to	O
employ	O
a	O
stochastic	B-Algorithm
diffusion	I-Algorithm
search	I-Algorithm
.	O
</s>
<s>
SDS	O
has	O
been	O
applied	O
to	O
diverse	O
problems	O
such	O
as	O
text	B-Algorithm
search	I-Algorithm
[	O
Bishop	O
,	O
1989 ]	O
,	O
object	O
recognition	O
[	O
Bishop	O
,	O
1992 ]	O
,	O
feature	O
tracking	O
[	O
Grech-Cini	O
,	O
1993 ]	O
,	O
mobile	O
robot	O
self-localisation	O
[	O
Beattie	O
,	O
1998 ]	O
and	O
site	O
selection	O
for	O
wireless	B-General_Concept
networks	I-General_Concept
[	O
Whitaker	O
,	O
2002 ]	O
.	O
</s>
<s>
Analysis	O
of	O
SDS	O
has	O
investigated	O
its	O
global	O
optimality	O
and	O
convergence	B-Architecture
[	O
Nasuto	O
,	O
1998 ]	O
,	O
linear	O
time	O
complexity	O
[	O
Nasuto	O
et	O
al.	O
,	O
1999 ]	O
,	O
robustness	B-Application
[	O
Myatt	O
,	O
2004 ]	O
,	O
and	O
resource	O
allocation	O
[	O
Nasuto	O
,	O
1999 ]	O
under	O
a	O
variety	O
of	O
search	O
conditions	O
.	O
</s>
