<s>
Unconventional	B-Device
computing	I-Device
is	O
computing	O
by	O
any	O
of	O
a	O
wide	O
range	O
of	O
new	O
or	O
unusual	O
methods	O
.	O
</s>
<s>
It	O
is	O
also	O
known	O
as	O
alternative	B-Device
computing	I-Device
.	O
</s>
<s>
Historically	O
,	O
mechanical	B-Device
computers	I-Device
were	O
used	O
in	O
industry	O
before	O
the	O
advent	O
of	O
the	O
transistor	B-Application
.	O
</s>
<s>
Mechanical	B-Device
computers	I-Device
retain	O
some	O
interest	O
today	O
both	O
in	O
research	O
and	O
as	O
analogue	O
computers	O
.	O
</s>
<s>
Some	O
mechanical	B-Device
computers	I-Device
have	O
a	O
theoretical	O
or	O
didactic	O
relevance	O
,	O
such	O
as	O
billiard-ball	B-Application
computers	I-Application
,	O
while	O
hydraulic	O
ones	O
like	O
the	O
MONIAC	B-Device
or	O
the	O
Water	B-Device
integrator	I-Device
were	O
used	O
effectively	O
.	O
</s>
<s>
The	O
domino	B-Device
computer	I-Device
is	O
another	O
theoretically	O
interesting	O
mechanical	O
computing	O
scheme	O
.	O
</s>
<s>
Examples	O
of	O
analog	O
computing	O
devices	O
include	O
slide	O
rules	O
,	O
nomograms	B-Application
,	O
and	O
complex	O
mechanisms	O
for	O
process	O
control	O
and	O
protective	O
relays	O
.	O
</s>
<s>
Most	O
modern	O
computers	O
are	O
electronic	O
computers	O
with	O
the	O
Von	B-Architecture
Neumann	I-Architecture
architecture	I-Architecture
based	O
on	O
digital	O
electronics	O
,	O
with	O
extensive	O
integration	O
made	O
possible	O
following	O
the	O
invention	O
of	O
the	O
transistor	B-Application
and	O
the	O
scaling	O
of	O
Moore	O
's	O
law	O
.	O
</s>
<s>
Unconventional	B-Device
computing	I-Device
is	O
,	O
according	O
to	O
a	O
conference	O
description	O
,	O
"	O
an	O
interdisciplinary	O
research	O
area	O
with	O
the	O
main	O
goal	O
to	O
enrich	O
or	O
go	O
beyond	O
the	O
standard	O
models	O
,	O
such	O
as	O
the	O
Von	B-Architecture
Neumann	I-Architecture
computer	I-Architecture
architecture	I-Architecture
and	O
the	B-Architecture
Turing	I-Architecture
machine	I-Architecture
,	O
which	O
have	O
dominated	O
computer	O
science	O
for	O
more	O
than	O
half	O
a	O
century	O
"	O
.	O
</s>
<s>
This	O
computing	O
behavior	O
can	O
be	O
"	O
simulated	O
"	O
using	O
the	O
classical	O
silicon-based	O
micro-transistors	O
or	O
solid	O
state	O
computing	O
technologies	O
,	O
but	O
aim	O
to	O
achieve	O
a	O
new	O
kind	O
of	O
computing	O
.	O
</s>
<s>
A	O
billiard-ball	B-Application
computer	I-Application
is	O
a	O
type	O
of	O
mechanical	B-Device
computer	I-Device
that	O
uses	O
the	O
motion	O
of	O
spherical	O
billiard	O
balls	O
to	O
perform	O
computations	O
.	O
</s>
<s>
A	O
domino	B-Device
computer	I-Device
is	O
a	O
mechanical	B-Device
computer	I-Device
that	O
uses	O
standing	O
dominoes	O
to	O
represent	O
the	O
amplification	O
or	O
logic	O
gating	O
of	O
digital	O
signals	O
.	O
</s>
<s>
Both	O
billiard-ball	B-Application
computers	I-Application
and	O
domino	B-Device
computers	I-Device
are	O
examples	O
of	O
unconventional	B-Device
computing	I-Device
methods	O
that	O
use	O
physical	O
objects	O
to	O
perform	O
computation	O
.	O
</s>
<s>
Fluidic	O
devices	O
operate	O
without	O
moving	O
parts	O
and	O
can	O
use	O
nonlinear	O
amplification	O
,	O
similar	O
to	O
transistors	B-Application
in	O
electronic	O
digital	O
logic	O
.	O
</s>
<s>
Quantum	O
computing	O
,	O
perhaps	O
the	O
most	O
well-known	O
and	O
developed	O
unconventional	B-Device
computing	I-Device
method	O
,	O
is	O
a	O
type	O
of	O
computation	O
that	O
utilizes	O
the	O
principles	O
of	O
quantum	O
mechanics	O
,	O
such	O
as	O
superposition	O
and	O
entanglement	O
,	O
to	O
perform	O
calculations	O
.	O
</s>
<s>
DNA	O
computing	O
is	O
a	O
branch	O
of	O
unconventional	B-Device
computing	I-Device
that	O
uses	O
DNA	O
and	O
molecular	O
biology	O
hardware	O
to	O
perform	O
calculations	O
.	O
</s>
<s>
While	O
these	O
systems	O
have	O
largely	O
remained	O
theoretical	O
,	O
some	O
have	O
been	O
shown	O
to	O
have	O
the	O
potential	O
to	O
solve	O
NP-complete	O
problems	O
and	O
have	O
been	O
proposed	O
as	O
hardware	O
implementations	O
for	O
unconventional	B-Device
computing	I-Device
.	O
</s>
<s>
These	O
systems	O
can	O
be	O
implemented	O
using	O
a	O
variety	O
of	O
hardware	O
,	O
such	O
as	O
memristors	O
,	O
spintronic	O
memories	O
,	O
and	O
transistors	B-Application
,	O
and	O
can	O
be	O
trained	O
using	O
a	O
range	O
of	O
software-based	O
approaches	O
,	O
including	O
error	O
backpropagation	O
and	O
canonical	O
learning	O
rules	O
.	O
</s>
<s>
Ternary	O
computing	O
is	O
a	O
type	O
of	O
computing	O
that	O
uses	O
ternary	B-Language
logic	I-Language
,	O
or	O
base	O
3	O
,	O
in	O
its	O
calculations	O
rather	O
than	O
the	O
more	O
common	O
binary	O
system	O
.	O
</s>
<s>
Reversible	O
computing	O
is	O
a	O
type	O
of	O
unconventional	B-Device
computing	I-Device
where	O
the	O
computational	O
process	O
can	O
be	O
reversed	O
to	O
some	O
extent	O
.	O
</s>
<s>
Chaos	O
computing	O
is	O
a	O
type	O
of	O
unconventional	B-Device
computing	I-Device
that	O
utilizes	O
chaotic	O
systems	O
to	O
perform	O
computation	O
.	O
</s>
