<s>
An	O
efficiently	B-General_Concept
updatable	I-General_Concept
neural	I-General_Concept
network	I-General_Concept
(	O
NNUE	B-General_Concept
,	O
a	O
Japanese	O
wordplay	O
on	O
Nue	O
,	O
sometimes	O
stylised	O
as	O
ƎUИИ	O
)	O
is	O
a	O
neural	O
network-based	O
evaluation	B-General_Concept
function	I-General_Concept
whose	O
inputs	O
are	O
piece-square	O
tables	O
,	O
or	O
variants	O
thereof	O
like	O
the	O
king-piece-square	O
table	O
.	O
</s>
<s>
NNUE	B-General_Concept
is	O
used	O
primarily	O
for	O
the	O
leaf	O
nodes	O
of	O
the	O
alpha	B-Algorithm
–	I-Algorithm
beta	I-Algorithm
tree	O
.	O
</s>
<s>
While	O
being	O
slower	O
than	O
handcrafted	O
evaluation	B-General_Concept
functions	I-General_Concept
,	O
NNUE	B-General_Concept
does	O
not	O
suffer	O
from	O
the	O
'	O
blindness	O
beyond	O
the	O
current	O
move	O
 '	O
problem	O
.	O
</s>
<s>
NNUE	B-General_Concept
was	O
invented	O
by	O
Yu	O
Nasu	O
and	O
introduced	O
to	O
computer	B-Application
shogi	I-Application
in	O
2018	O
.	O
</s>
<s>
On	O
6	O
August	O
2020	O
,	O
NNUE	B-General_Concept
was	O
for	O
the	O
first	O
time	O
ported	O
to	O
a	O
chess	O
engine	O
,	O
Stockfish	B-Application
12	O
.	O
</s>
<s>
Since	O
2021	O
,	O
all	O
of	O
the	O
top	O
rated	O
classical	O
chess	O
engines	O
such	O
as	O
Komodo	B-Application
Dragon	I-Application
have	O
an	O
NNUE	B-General_Concept
implementation	O
to	O
remain	O
competitive	O
.	O
</s>
<s>
NNUE	B-General_Concept
runs	O
efficiently	O
on	O
central	B-General_Concept
processing	I-General_Concept
units	I-General_Concept
without	O
a	O
requirement	O
for	O
a	O
graphics	B-Architecture
processing	I-Architecture
unit	I-Architecture
(	O
GPU	B-Architecture
)	O
.	O
</s>
<s>
The	O
neural	B-Architecture
network	I-Architecture
used	O
for	O
the	O
original	O
2018	O
computer	B-Application
shogi	I-Application
implementation	O
consists	O
of	O
four	O
weight	O
layers	O
:	O
W1	O
(	O
16-bit	O
integers	O
)	O
and	O
W2	O
,	O
W3	O
and	O
W4	O
(	O
8-bit	O
)	O
.	O
</s>
<s>
It	O
used	O
incremental	O
computation	O
and	O
single	B-Device
instruction	I-Device
multiple	I-Device
data	I-Device
(	O
SIMD	B-Device
)	O
techniques	O
along	O
with	O
appropriate	O
intrinsic	B-Application
instructions	I-Application
.	O
</s>
