<s>
Metadata	B-Language
modeling	I-Language
is	O
a	O
type	O
of	O
metamodeling	O
used	O
in	O
software	B-General_Concept
engineering	I-General_Concept
and	O
systems	O
engineering	O
for	O
the	O
analysis	O
and	O
construction	O
of	O
models	O
applicable	O
to	O
and	O
useful	O
for	O
some	O
predefined	O
class	O
of	O
problems	O
.	O
</s>
<s>
First	O
of	O
all	O
,	O
a	O
concept	O
is	O
a	O
simple	O
version	O
of	O
a	O
Unified	B-Language
Modeling	I-Language
Language	I-Language
(	O
UML	B-Language
)	O
class	O
.	O
</s>
<s>
Part	O
of	O
the	O
process-data	B-Application
diagram	I-Application
of	O
the	O
requirements	O
workflow	O
in	O
the	O
Unified	O
Process	O
is	O
illustrated	O
.	O
</s>
<s>
The	O
example	O
is	O
a	O
fragment	O
of	O
the	O
process-data	B-Application
diagram	I-Application
of	O
the	O
requirements	O
analysis	O
in	O
the	O
Unified	O
Process	O
.	O
</s>
<s>
In	O
Figure	O
10	O
aggregation	O
is	O
exemplified	O
by	O
a	O
fragment	O
of	O
the	O
requirements	O
capture	O
workflow	O
in	O
UML-Based	O
Web	O
Engineering	O
.	O
</s>
