<s>
Zen	B-Application
,	O
sold	O
as	O
Tencho	B-Application
no	I-Application
Igo	I-Application
(	O
,	O
literally	O
Zenith	B-Application
Go	I-Application
)	O
in	O
Japan	O
,	O
is	O
a	O
closed	B-Application
source	I-Application
Go	O
playing	O
engine	O
developed	O
by	O
Yoji	O
Ojima	O
( 尾島陽児	O
)	O
,	O
a	O
Japanese	O
Go	O
programmer	O
.	O
</s>
<s>
Zen	B-Application
won	O
a	O
gold	O
medal	O
in	O
14th	O
Computer	O
Olympiad	O
in	O
May	O
2009	O
.	O
</s>
<s>
In	O
2011	O
,	O
Zen19D	O
reached	O
5	O
dan	O
on	O
the	O
KGS	B-Application
Go	I-Application
Server	I-Application
,	O
playing	O
games	O
of	O
15	O
seconds	O
per	O
move	O
.	O
</s>
<s>
The	O
account	O
which	O
reached	O
that	O
rank	O
uses	O
a	O
cluster	O
version	O
of	O
Zen	B-Application
running	O
on	O
a	O
26-core	O
machine	O
.	O
</s>
<s>
In	O
2012	O
,	O
Zen	B-Application
beat	O
Takemiya	O
Masaki	O
9p	O
by	O
11	O
points	O
(	O
it	O
received	O
five	O
handicap	O
stones	O
)	O
,	O
followed	O
by	O
a	O
20-point	O
win	O
(	O
receiving	O
four	O
handicap	O
stones	O
)	O
in	O
the	O
6th	O
E&C	O
Symposium	O
in	O
Japan	O
.	O
</s>
<s>
Zen	B-Application
defeated	O
Kobayashi	O
Koichi	O
(	O
Zen	B-Application
receiving	O
three	O
handicap	O
stones	O
)	O
in	O
the	O
4th	O
Densei-sen	O
on	O
23	O
March	O
2016	O
.	O
</s>
<s>
Zen	B-Application
's	O
first	O
commercial	O
version	O
was	O
released	O
in	O
Japan	O
on	O
18	O
September	O
2009	O
.	O
</s>
<s>
Zen	B-Application
2	O
was	O
released	O
on	O
27	O
August	O
2010	O
,	O
Zen	B-Application
3	O
on	O
30	O
September	O
2011	O
,	O
Zen	B-Application
4	O
on	O
27	O
July	O
2012	O
,	O
and	O
Zen	B-Application
5	O
on	O
13	O
December	O
2013	O
.	O
</s>
<s>
After	O
the	O
AlphaGo	B-Application
AI	O
defeated	O
professional	O
players	O
Fan	O
Hui	O
2p	O
and	O
Lee	O
Sedol	O
9p	O
in	O
2015	O
and	O
2016	O
,	O
Yoji	O
was	O
inspired	O
to	O
upgrade	O
Zen	B-Application
with	O
deep	B-Algorithm
learning	I-Algorithm
algorithms	O
.	O
</s>
<s>
Its	O
win	O
in	O
that	O
match	O
made	O
it	O
the	O
second	O
Go-playing	O
computer	O
program	O
(	O
after	O
AlphaGo	B-Application
)	O
to	O
win	O
against	O
a	O
top	O
human	O
player	O
without	O
receiving	O
handicap	O
stones	O
.	O
</s>
<s>
Around	O
the	O
same	O
time	O
,	O
DeepZenGo	O
participated	O
in	O
the	O
2017	O
Computer	O
Go	O
UEC	O
Cup	O
,	O
coming	O
second	O
behind	O
Fine	B-Application
Art	I-Application
.	O
</s>
