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3. Stores.
In
Extend,
there
is
a
number
of
blocks
represent
storage.
These storage areas can contain items of different types of items with
attributes that define type.
4. Decision. A decision
in
Extend + BPR
TM
is
modeled
by
using
a
Decision block, which compares two variables, and a Select DE
Output block, which chooses a path based on the received value.
5. Events. Extend
+
BPR
TM
supports
implicit
and
explicit
events.
Extend + BPR
TM
also
has the capability of generating events
that
will
shut
down
other
operations
while
they
are
executing.
Interrupts
can
shut down operation, change the value of attributes associated with
items, restart operations and so on.
6. Mathematical and
Logical Operations.
Extend + BPR
TM
has a
large
library
of
mathematical
and
logical operation available. The
logical and mathematical blocks that control the behavior of a model
can
be
implemented
in
two
ways.
The
first
is
using
visual
graphic
iconic blocks. The other, is hidden from the viewer or presented
visually as part of the model
itself.
7. Queues. It arises when the short term demand for service exceeds the
capacity as shown
in
Figure 2.21 below. Often
it caused by
random
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