<s>
Multimodal	B-Application
search	I-Application
is	O
a	O
type	O
of	O
search	B-Application
that	O
uses	O
different	O
methods	O
to	O
get	O
relevant	O
results	O
.	O
</s>
<s>
They	O
can	O
use	O
any	O
kind	O
of	O
search	B-Application
,	O
search	B-Application
by	I-Application
keyword	I-Application
,	O
search	B-Application
by	O
concept	O
,	O
search	B-Application
by	I-Application
example	I-Application
,	O
etc	O
.	O
</s>
<s>
A	O
multimodal	B-Application
search	I-Application
engine	O
is	O
designed	O
to	O
imitate	O
the	O
flexibility	O
and	O
agility	O
of	O
how	O
the	O
human	O
mind	O
works	O
to	O
create	O
,	O
process	O
and	O
refuse	O
irrelevant	O
ideas	O
.	O
</s>
<s>
So	O
,	O
the	O
more	O
elements	O
you	O
have	O
in	O
the	O
input	O
of	O
the	O
search	B-Application
engine	I-Application
to	O
compare	O
,	O
the	O
more	O
accurate	B-Architecture
the	O
results	O
can	O
be	O
.	O
</s>
<s>
Multimodal	B-Application
search	I-Application
engines	O
use	O
different	O
inputs	O
of	O
different	O
nature	O
and	O
methods	O
of	O
search	B-Application
at	O
the	O
same	O
time	O
with	O
the	O
possibility	O
of	O
combining	O
the	O
results	O
by	O
merging	O
all	O
of	O
the	O
input	O
elements	O
of	O
the	O
search	B-Application
.	O
</s>
<s>
There	O
are	O
also	O
engines	O
that	O
can	O
use	O
a	O
feedback	O
of	O
the	O
results	O
with	O
the	O
evaluation	O
of	O
the	O
user	O
to	O
perform	O
a	O
more	O
appropriate	O
and	O
relevant	O
search	B-Application
.	O
</s>
<s>
Touch	O
screens	O
,	O
motion	O
sensors	O
and	O
voice	B-Application
recognition	I-Application
are	O
now	O
featured	O
on	O
mobile	O
devices	O
called	O
smartphones	B-Application
.	O
</s>
<s>
All	O
the	O
features	O
and	O
functions	O
make	O
it	O
possible	O
to	O
execute	O
multimodal	B-Application
searches	I-Application
from	O
any	O
place	O
in	O
the	O
world	O
at	O
any	O
time	O
.	O
</s>
<s>
The	O
use	O
of	O
text	O
is	O
an	O
option	O
,	O
as	O
well	O
as	O
multimedia	O
searching	O
,	O
image	B-General_Concept
,	O
video	O
,	O
audio	B-Application
,	O
and	O
voice	B-Application
search	I-Application
.	O
</s>
<s>
Even	O
the	O
location	B-Application
of	I-Application
the	I-Application
user	I-Application
can	O
help	O
the	O
search	B-Application
engine	I-Application
to	O
perform	O
a	O
more	O
effective	O
search	B-Application
,	O
adaptable	O
to	O
every	O
situation	O
.	O
</s>
<s>
Nowadays	O
,	O
different	O
ways	O
to	O
interact	O
with	O
a	O
search	B-Application
engine	I-Application
are	O
being	O
discovered	O
,	O
in	O
terms	O
of	O
input	O
elements	O
of	O
the	O
search	B-Application
and	O
in	O
the	O
variety	O
of	O
results	O
obtained	O
.	O
</s>
<s>
Many	O
queries	O
from	O
mobiles	O
are	O
location-based	B-Application
(	O
LBS	O
)	O
,	O
that	O
use	O
the	O
location	B-Application
of	I-Application
the	I-Application
user	I-Application
to	O
interact	O
with	O
the	O
applications	O
.	O
</s>
<s>
Therefore	O
,	O
multimodal	B-Application
searches	I-Application
use	O
not	O
only	O
audiovisual	O
content	O
that	O
the	O
user	O
provides	O
directly	O
,	O
but	O
also	O
the	O
context	O
where	O
the	O
user	O
is	O
,	O
like	O
his/her	O
location	O
,	O
language	O
,	O
time	O
at	O
the	O
moment	O
,	O
web	O
site	O
or	O
document	O
where	O
the	O
user	O
is	O
surfing	O
,	O
or	O
other	O
elements	O
that	O
can	O
help	O
to	O
improve	O
of	O
a	O
search	B-Application
in	O
every	O
situation	O
.	O
</s>
<s>
The	O
multimodal	B-Application
search	I-Application
engine	O
works	O
in	O
parallel	O
,	O
whilst	O
at	O
the	O
same	O
time	O
,	O
performs	O
a	O
search	B-Application
of	O
more	O
to	O
less	O
relevance	O
of	O
every	O
element	O
introduced	O
directly	O
or	O
indirectly	O
(	O
personal	O
context	O
)	O
.	O
</s>
<s>
There	O
are	O
search	B-Application
engines	I-Application
that	O
do	O
this	O
automatically	O
,	O
however	O
there	O
are	O
also	O
engines	O
where	O
the	O
user	O
can	O
do	O
it	O
manually	O
,	O
giving	O
more	O
or	O
less	O
weight	O
to	O
every	O
element	O
of	O
the	O
search	B-Application
.	O
</s>
<s>
It	O
’s	O
also	O
important	O
that	O
the	O
user	O
provides	O
the	O
appropriate	O
and	O
essential	O
information	O
for	O
the	O
search	B-Application
;	O
too	O
much	O
information	O
can	O
confuse	O
the	O
system	O
and	O
provide	O
unsatisfactory	O
results	O
.	O
</s>
<s>
With	O
multimodal	B-Application
searches	I-Application
users	O
can	O
get	O
better	O
results	O
than	O
with	O
a	O
simple	O
search	B-Application
,	O
but	O
multimodal	B-Application
searches	I-Application
must	O
process	O
more	O
input	O
information	O
.	O
</s>
<s>
An	O
efficient	O
search	B-Application
engine	I-Application
interprets	O
the	O
query	O
of	O
the	O
users	O
,	O
realizes	O
his/her	O
intention	O
and	O
applies	O
a	O
strategy	O
to	O
use	O
an	O
appropriate	O
search	B-Application
,	O
i.e.	O
</s>
<s>
Nowadays	O
,	O
existing	O
multimodal	B-Application
search	I-Application
engines	O
are	O
not	O
very	O
complex	O
,	O
and	O
some	O
of	O
them	O
are	O
in	O
an	O
experimental	O
phase	O
.	O
</s>
<s>
Some	O
of	O
the	O
more	O
simple	O
engines	O
are	O
Google	B-Application
Images	I-Application
or	O
Bing	B-Application
,	O
web	O
interfaces	O
that	O
use	O
text	O
and	O
images	B-Application
as	I-Application
inputs	I-Application
to	O
find	O
images	O
in	O
the	O
output	O
.	O
</s>
<s>
MMRetrieval	O
is	O
a	O
multimodal	O
experimental	O
search	B-Application
engine	I-Application
that	O
uses	O
multilingual	O
and	O
multimedia	O
information	O
through	O
a	O
web	O
interface	O
.	O
</s>
<s>
The	O
engine	O
also	O
provides	O
different	O
multistage	O
retrieval	O
,	O
as	O
well	O
as	O
a	O
single	O
text	O
index	O
baseline	O
to	O
be	O
able	O
to	O
compare	O
all	O
the	O
different	O
phases	O
of	O
search	B-Application
.	O
</s>
