<s>
Activity-centered	B-General_Concept
design	I-General_Concept
(	O
ACD	O
)	O
is	O
an	O
extension	O
of	O
the	O
Human-centered	O
design	O
paradigm	O
in	O
interaction	B-General_Concept
design	I-General_Concept
.	O
</s>
<s>
When	O
working	O
with	O
activity-centered	B-General_Concept
design	I-General_Concept
,	O
the	O
designers	O
use	O
research	O
to	O
get	O
insights	O
of	O
the	O
users	O
.	O
</s>
