<s>
Data	B-Operating_System
centre	I-Operating_System
power	O
generators	O
that	O
activate	O
when	O
the	O
normal	O
power	O
source	O
is	O
unavailable	O
.	O
</s>
<s>
Redundant	O
systems	O
are	O
often	O
used	O
in	O
data	B-Operating_System
centers	I-Operating_System
to	O
maximise	O
uptime	O
or	O
availability	O
of	O
computer	O
systems	O
.	O
</s>
<s>
An	O
example	O
for	O
the	O
use	O
of	O
N+1	B-Application
redundancy	I-Application
is	O
the	O
German	O
power	O
system	O
,	O
where	O
it	O
is	O
called	O
"	O
(	O
n-1	O
)	O
Sicherheit	O
"	O
in	O
German	O
.	O
</s>
