Overview
SAS Simulation Studio
12.1, a discrete event simulation application for Windows environments,
adds several features that improve your ability to build, explore,
and work with large, complex discrete-event simulation models. Large
models present a number of challenges to a graphical user interface
such as that of SAS Simulation Studio. Connection of model components,
navigation within a model, identification of objects or areas of interest,
and management of different levels of modeling are all tasks that
can become more difficult as the model size grows significantly beyond
what can be displayed on one screen. An indirect effect of model growth
is an increased number of factors and responses that are needed to
parameterize and investigate the performance of the system being modeled.
Improvements in SAS
Simulation Studio 12.1 address each of these issues. In SAS Simulation
Studio, you connect blocks by dragging the cursor to create links
between output and input ports on regular blocks and Connector blocks.
SAS Simulation Studio 12.1 automatically scrolls the display of the
Model window as you drag the link that is being created from its origin
to its destination, thus enabling you to create a link between two
blocks that are located far apart (additionally you can connect any
two blocks by clicking on the OutEntity port of the first block and
then clicking on the InEntity port of the second block). Automatic
scrolling also enables you to navigate a large model more easily.
To move to a new area in the Model window, you can simply hold down
the left mouse button and drag the visible region of the model to
the desired area. This works for simple navigation and for moving
a block to a new, remote location in the model.
SAS Simulation Studio
12.1 also enables you to search among the blocks in a model and identify
the blocks that have a specified type, a certain character string
in their label, or both. From the listing of identified blocks, you
can open the Properties dialog box for each identified block and edit
its settings. Thus, if you can identify a set of blocks that need
similar updates, then you can make these updates without manually
searching through the model for qualifying blocks and editing them
individually. For very large models, this capability not only makes
the update process easier but also makes it more thorough because
you can identify qualifying blocks centrally.
When you design experiments
for large simulation models, you often need a large number of factors
to parameterize the model and a large number of responses to track
system performance in sufficient detail. This was a challenge prior
to SAS Simulation Studio 12.1 because the Experiment window displayed
factors and responses in the header row of a table, with design points
and their replications’ results displayed in the rows below.
A very large number of factors and responses did not fit on one screen
in this display scheme, and you had to scroll across the Experiment
window to view all of them.
SAS Simulation Studio
12.1 provides you with two alternative configurations for the Experiment
window. The Design Matrix tab presents the tabular layout described
earlier. The Design Point tab presents each design point in its own
display. Factors and responses (summarized over replications) are
displayed in separate tables, each with the factor or response names
appearing in one column and the respective values in a second column.
This layout enables a large number of factors and responses to be
displayed. Response values for each replication of the design point
can be displayed in a separate window.
SAS Simulation Studio
12.1 enhances its multilevel model management features by introducing
the submodel component (experimental). Like the compound block, the
submodel encapsulates a group of SAS Simulation Studio blocks and
their connections, but the submodel outpaces the compound block in
some important ways. The submodel, when expanded, opens in its own
window. This means a submodel in its collapsed form can be placed
close to other blocks in the Model window without requiring space
for its expanded form (as is needed for compound blocks). The most
important property of the submodel is its ability to be copied and
instantiated in several locations simultaneously, whether in the same
model, in different models in the same project, or in different projects.
Each such instance is a direct reference to the original submodel,
not a disconnected copy. Thus you can edit the submodel by editing
any of its instances; changes that are made to any instance are propagated
to all current and future instances of the submodel. This feature
enables you to maintain consistency across your models and projects.
Finally, SAS Simulation
Studio 12.1 introduces powerful new animation controls that should
prove highly useful in debugging simulation models. In the past, animation
could be switched on or off and its speed controlled, but these choices
were made for the entire model. If you needed to animate a particular
segment of the model, perhaps during a specific time span for the
simulation clock, you had to focus your attention on that area and
pay special attention when the time period of interest arrived. In
SAS Simulation Studio 12.1 you can select both the area of the model
to animate (by selecting a block or a compound block) and the time
period over which animation should occur (by specifying the start
and end times for animation). You can also control simulation speed
for each such selection. Multiple selections are supported so that
you can choose to animate several areas of the model, each during
its defined time period and at its chosen speed.