This document and any accompanying Rockwell Software products are copyrighted by Rockwell Automation
Technologies, Inc. Any reproduction and/or distribution without prior written consent from Rockwell Automation
Technologies, Inc. is strictly prohibited. Please refer to the license agreement for details.
Arena and Rockwell Automation are registered trademarks of Rockwell Automation, Inc.
Other Trademarks
Warran ty
ActiveX, Microsoft, Microsoft Access, SQL Server, Visual Basic, Visual C++, Visual SourceSafe, Windows, Windows
ME, Windows NT, Windows 2000, Windows Server 2003, and Windows XP are either registered trademarks or
trademarks of Microsoft Corporation in the United States and/or other countries.
Adobe, Acrobat, and Reader are either registered trademarks or trademarks of Adobe Systems Incorporated in the
United States and/or other countries.
ControlNet is a registered trademark of ControlNet International.
DeviceNet is a trademark of the Open DeviceNet Vendor Association, Inc. (ODVA)
Ethernet is a registered trademark of Digital Equipment Corporation, Intel, and Xerox Corporation
OLE for Process Control (OPC) is a registered trademark of the OPC Foundation.
Oracle, SQL*Net, and SQL*Plus are registered trademarks of Oracle Corporation.
All other trademarks are the property of their respective holders and are hereby acknowledged.
This product is warranted in accordance with the product license. The product’s performance may be affected by system
configuration, the application being performed, operator control, maintenance and other related factors. Rockwell
Automation is not responsible for these intervening factors. The instructions in this document do not cover all the
details or variations in the equipment, procedure, or process described, nor do they provide directions for meeting every
possible contingency during installation, operation, or maintenance. This product’s implementation may vary among
users.
This document is current as of the time of release of the product; however, the accompanying software may have
changed since the release. Rockwell Automation, Inc. reserves the right to change any information contained in this
document or the software at anytime without prior notice. It is your responsibility to obtain the most current information
available from Rockwell when installing or using this product.
Version: 12.00.00 (CPR9)
Modified: October 8, 2007 1:24 pm
Publish process maps on a Web page. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 140
Index141
• • • • •
vii
ARENA USER’S GUIDE
• • • • •
viii
1
Welcome
What is Arena software?
Arena software enables you to bring the power of modeling and simulation to your
business. It is designed for analyzing the impact of changes involving significant and
complex redesigns associated with supply chain, manufacturing, processes, logistics,
distribution and warehousing, and service systems. Arena software provides the
maximum flexibility and breadth of application coverage to model any desired level of
detail and complexity.
Typical scenarios include:
Detailed analysis of any type of manufacturing system, including material-handling
components
Analysis of complex customer service and customer management systems
Analysis of global supply chains that include warehousing, transportation, and
logistics systems
Predicting system performance based on key metrics such as costs, throughput, cycle
times, and utilizations
Identifying process bottlenecks such as queue build ups and over-utilization of
resources
Planning staff, equipment, or material requirements.
1 • Welcome
In addition to the Arena Professional Edition, Rockwell Automation offers a full suite of
products to provide enterprise-wide simulation, optimization, and 3D model animation.
Intended audience
Arena software is designed for manufacturing or business process consultants and analysts
and industrial or systems engineers. It is typically deployed as an enterprise business
analysis and productivity tool.
We assume that you are familiar with the basic concepts and terms used in these types of
systems. You are interested in improving business or manufacturing productivity and are
responsible for evaluating and predicting the impact of proposed strategic and tactical
changes to help improve performance. A familiarity with computers and the Microsoft
Windows
in simulation is also helpful.
®
operating system is assumed. A familiarity with the concepts and terms used
®
1
ARENA USER’S GUIDE
• • • • •
Where can I go for help?
Our commitment to your success starts with the suite of learning aids and assistance we
provide for Arena. Whether you’re new to simulation or a seasoned veteran putting a new
tool to use, you’ll quickly feel at home with the Arena software.
Reference the user’s guides
The documentation set for this package is comprised of user manuals for the software and
template components, as well as a separate Variables Guide reference that provides
complete descriptions of Arena variables found in the Arena product templates.
D
OCUMENT CONVENTIONS
Throughout the guides, a number of style conventions are used to help identify material.
New terms and concepts may be emphasized by use of italics or bold; file menu paths are
in bold with a (>) separating the entries (e.g., go to Help > Arena Help); text you are
asked to type is shown in Courier Bold (e.g., in this field, type Work Week), and dialog
box and window button names are shown in bold (e.g., click OK).
Explore our examples
Arena is accompanied by a number of sample models that illustrate many of the commonly used approaches for capturing the essence of manufacturing processes. Examples
are provided for both job shop and flow shop environments. For a description of and list
of Arena’s examples, go to Help > Arena Help. On the Contents tab, choose Model Building Basics, and then select Viewing Arena Example Models.
Get help
Online help is always at your fingertips! Arena incorporates the latest in help features,
including What’s This? help that displays a brief description of fields in dialogs, context-
sensitive help on menu and toolbar buttons, and a help button on each of Arena’s modules.
Just refer to the Arena help table of contents and index for a list of all help topics.
Use the SMARTs library
As you craft models of your own manufacturing processes, use our SMARTs library to
explore how to best use Arena. This suite of tutorial models covers topics ranging from
modeling resources to animation techniques. The library is organized into categories to
help you find the right model with ease. When you’re wondering how to take the next step
in your model, browse the SMARTs library for a ready-made solution. For a list of
categories and their related SMARTS, go to Help > Arena Help. On the Contents tab,
first click Model Building Basics, and then Learning Arena with SMART Files.
2
1 • WELCOME
Access the Arena Symbol Factory
Arena animations can be enhanced using Arena Symbol Factory’s extensive library of
symbols. These symbols can be used for entity, resource, transporter or global pictures; or
as graphic symbols within a model window. You can copy these symbols directly to the
Arena model window, add them to your own libraries (.plb files), or add them to any of
the Arena picture library files.
Get phone support
Rockwell Automation provides full support for the entire Arena family of products. Questions concerning installation, how modules work, the use of the model editor, and the use
of the software are handled by technical support.
A
RENA TECHNICAL SUPPORT INCLUDES
(for users on active maintenance) a technical support hotline and e-mail address
staffed by full-time, experienced professionals
help with installation problems or questions related to the software’s requirements
troubleshooting
limited support regarding the interaction of Arena with other programs
support of the Arena Object Model, which is used in Microsoft Visual Basic for
Applications
:
• • • • •
1 • Welcome
If you call the support line (1.440.646.3434 for calls originating in the U.S/Canada), you
should be at your computer and be prepared to give the following information:
the product serial number
the product version number
the operating system you are using
the exact wording of any messages that appeared on your screen
a description of what happened and what you were doing when the problem occurred
a description of how you tried to solve the problem
Get Web support
In addition to phone support, the Rockwell Automation Customer Support Center offers
extensive online knowledgebases of tech notes and frequently asked questions for support
of non-urgent issues. These databases are updated daily by our support specialists.
To receive regular e-mail messages with links to the latest tech notes, software updates,
and firmware updates for the products that are of interest to you or to submit an online
support request, go to support.rockwellautomation.com
And be sure to check the Arena User Zone section of our Web site at www.ArenaSimulation.com. The User Zone links to a peer-to-peer forum on Arena topics and has a link to a
and select the Online link.
3
ARENA USER’S GUIDE
• • • • •
download page where you can check for possible software updates (patches). If you can’t
find the answer you need, contact your local representative or Arena technical support.
Get training
Do you need training? Rockwell Automation offers a standard training course comprised
of lecture and hands-on workshops designed to introduce you to the fundamental concepts
of modeling with Arena.
We also offer customized training courses designed to meet your specific needs. These
courses can be held in our offices or yours, and we can accommodate one person or
twenty. You design the course that’s right for you! Simply contact our consulting services
group to discuss how we can help you achieve success in your simulation efforts.
Get consulting services
Rockwell Automation provides expert consulting and turnkey implementation of the
entire Arena product suite. Please contact our offices for more information.
Contact us
We strive to help all of our customers become successful in their manufacturing improvement efforts. Toward this objective, we invite you to contact your local representative or
Rockwell Automation at any time that we may be of service to you.
Support E-mail: Arena-Support@ra.rockwell.com
Corporate E-mail: Arena-Info@ra.rockwell.com
Support phone: 1.440.646.3434
URL: www.ArenaSimulation.com
URL: www.rockwellautomation.com
4
2
Getting Started
Introduction
While you may not realize it quite yet, you now have the power to transform your
business. Whenever you and others in your organization are wondering “what if…?,” you
can look into the future to find the answer.
With Arena, you can:
Model your processes to define, document, and communicate.
Simulate the future performance of your system to understand complex relationships
and identify opportunities for improvement.
Visualize your operations with dynamic animation graphics.
Analyze how your system will perform in its “as-is” configuration and under a myriad
of possible “to-be” alternatives so that you can confidently choose the best way to run
your business.
Our task: Analyze a home mortgage application process
In this chapter, we will examine a simple mortgage application process to illustrate how
you can model, simulate, visualize, and analyze with Arena. To begin, we’ll look at the
process of receiving and reviewing a home mortgage application. We will build the flowchart shown below, introducing you to the process of modeling and simulating with
Arena.
2 • Getting Started
5
ARENA USER’S GUIDE
• • • • •
The Arena modeling environment
Project Bar
If Arena is not already running, start it from the Windows Start menu and navigate to
Programs > Rockwell Software > Arena. The Arena modeling environment will open
with a new model window, as shown below.
Model window
flowchart view
The Project Bar
usually is docked at
the left of the Arena
application window,
but can tear off or
dock at another
position like any
toolbar.
6
Model window
spreadsheet view
To model your process in Arena, you’ll work in three main regions of the application
window. The Project Bar hosts panels with the primary types of objects that you will work
with:
Basic Process, Advanced Process, and Advanced Transfer panels: Contain the
modeling shapes, called modules, that you’ll use to define your process.
Reports panel: Contains the reports that are available for displaying results of simula-
tion runs.
Navigate panel: Allows you to display different views of your model, including
navigating through hierarchical submodels and displaying a model thumbnail view.
In the model window, there are two main regions. The flowchart view will contain all of
your model graphics, including the process flowchart, animation, and other drawing
elements. The lower, spreadsheet view displays model data, such as times, costs, and other
parameters.
As we model the mortgage application process, we’ll work in all three of these regions of
Arena.
Map your process in a flowchart
Let’s start by examining what we’re going to do: Build a flowchart. The word itself—
flowchart—suggests two of the main concepts behind modeling and simulation. We’ll be
building a chart—also referred to as a process map or a model—that describes a flow.
This raises a key question in process modeling: What exactly is it that will flow through
the chart?
We’re modeling the process of reviewing mortgage applications. These mortgage applications are the items, referred to as entities, that will move through the process steps in our
model. They are the data, whether on paper or in electronic form, that are associated with
our client’s request for a mortgage. As we build the flowchart, it’s helpful to think of the
process from the perspective of the entity (the mortgage application), asking questions
like:
• • • • •
2 • GETTING STARTED
2 • Getting Started
Where do the mortgage applications enter the process?
What happens to them at each step?
What resources are needed to complete work?
First, we’ll draw the flowchart representing the mortgage application process. Refer to the
Mortgage Application Process Flowchart (shown previously) so you’ll know what we’ll
be creating.
Create the mortgage application entities
We’ll start the flowchart using a Create module, from the Basic Process panel. This is the
starting point for the flow of entities through the model.
1. Drag the Create module from the Basic Process panel into the model window.
A default name, Create 1, is given to the module when it’s placed. We’ll return later to
provide a more meaningful description as well as some data to support the simulation.
7
ARENA USER’S GUIDE
• • • • •
Every process flow
starts with a
Create module.
When you simulate
the flowchart,
individual entities
will be created
according to timing
information you
supply in the
Create module
properties. After it’s
created, each entity
moves from the
Create module to
the next shape in
the process flow.
If your Create and
Process weren’t
connected auto-
matically when you
placed the Process,
check the Object >
Auto-Connect menu
to verify that it’s
checked. If it’s not,
select it to turn on
this option.
8
Process the applications
Next in our flowchart is a Process module, from the Basic Process panel, representing the
Review Application step.
1. So that Arena will automatically connect the Process to the Create module, be sure
that the Create module is selected.
2. Drag a Process module from the Basic Process panel into the model window, placing
it to the right of the Create. Arena will automatically connect the two modules.
As with the Create, the Process module has a default name that we’ll replace later.
2 • GETTING STARTED
• • • • •
2 • Getting Started
Note: If no connection appears between Create and Process, click the Object > Connect menu
item or the Connect toolbar button to draw a connection. Your cursor will change to a cross hair.
Start the connection by clicking the exit point ( ) of the Create module, then click the entry point
( ) of the Process module to complete the connection. If you need to make multiple
connections, simply double-click the Connect button or select Object > Connect twice (the
Connect button will remain depressed to indicate it is in multi-connect mode). Then draw as
many connections as desired. A valid connection target (e.g., entry point, exit point, or operand
object) is now highlighted during a connection session if the pointer is hovered over it. To end the
multi-connection session, click again on the Connect option, press Esc, or right-click.
How do I use Snap and Grid?
If your flowchart shapes aren’t lining up properly, you can use Arena’s snap and grid
features to straighten them out. First, check the Snap option on the View menu so that
newly placed shapes will be positioned at regular snap points. To realign the shapes
you’ve already placed, select the main module shapes (the yellow boxes) by holding the
Ctrl key and clicking on each shape. Then, click the Arrange > Snap to Grid menu
option to adjust their positions to align with grid points.
You can display the grid by checking the Grid option on the View menu. Both snap and
grid are turned off by clicking on the menu option again, turning off the check box.
9
ARENA USER’S GUIDE
• • • • •
Decide whether applications are complete
After the Process, we have a Decide module, from the Basic Process panel, which determines whether the mortgage application is complete.
1. If you’re using the Auto-Connect feature (i.e., it’s checked on the Object > Auto-Connect menu), be sure that the Process module is selected so that the Decide will be
connected to it.
2. Drag a Decide module to the right of the Process module.
10
If the mortgage application has a complete set of information, it will leave the Decide
module from the right side of the diamond shape, representing the True condition. Incomplete applications (False result to the Decide test) will leave via the bottom connection.
Dispose the applications to terminate the process
Next we’ll place the Dispose module, from the Basic Process panel, representing accepted
applications, connecting to the True (right) output from the Decide shape. Then, we’ll
complete the flowchart with another Dispose for returned applications.
1. Select the Decide shape so that our first Dispose will be connected automatically.
2 • GETTING STARTED
• • • • •
Entity flow always
begins with a Create
module and termi-
nates with a Dispose
module. You may
have as many of each
of these modules as
you need to generate
entities into the model
and to remove them
when their process-
ing is complete.
2. Drag a Dispose module to the right of the Decide module. Arena will connect it to the
primary (True) exit point of the Decide module. (We won’t include a graphic display
since you’re now familiar with the drag-and-drop sequence.)
3. To add the second Dispose module, once again select the Decide module, so that
Arena will automatically connect its False exit point to the new Dispose module, and
drag another Dispose module below and to the right of the Decide module.
4. Drag and drop another Dispose module, placing it below and to the right of the Decide
shape, completing the process flowchart.
2 • Getting Started
What is a module?
In Arena, modules are the flowchart and data objects that define the process to be
simulated. All information required to simulate a process is stored in modules.
For now, we’re working with flowchart modules—those that are placed in the model
window to describe the process. In the Basic Process panel, these are the first eight
shapes:
Create: The start of process flow. Entities enter the simulation here.
Dispose: The end of process flow. Entities are removed from the simulation here.
Process: An activity, usually performed by one or more resources and requiring some
time to complete.
Decide: A branch in process flow. Only one branch is taken.
Batch: Collect a number of entities before they can continue processing.
Separate: Duplicate entities for concurrent or parallel processing, or separating a
previously established batch of entities.
Assign: Change the value of some parameter (during the simulation), such as the
entity’s type or a model variable.
Record: Collect a statistic, such as an entity count or cycle time.
Simulation settings are defined in the Run > Setup > Replication Parameters dialog
box. There is also a set of data modules for defining the characteristics of various process
elements, such as resources and queues.
11
ARENA USER’S GUIDE
• • • • •
Define model data
Now that we’ve drawn the basic flowchart for our mortgage application process, let’s
define the data associated with the modules, including the name of the module and information that will be used when we simulate the process.
Initiate mortgage application (Create module)
First, let’s visit the Create module, which will be named Initiate Mortgage Application. Its
data will include the type of entity to be created—in our case, a mortgage Application. We
also need to define how often mortgage applications are initiated. We’ll use an average of
2 hours between applicants as a starting point for our model, and we’ll make this a
random activity to represent the natural variation in the timing of mortgage applications
being submitted.
1. Double-click the Create module to open its property dialog box.
2. In the Name field, type
3. For the Entity Type, name our entities by typing
4. Type
5. Click OK to close the dialog box.
For now, we’ll leave the default values for the other Create module properties. Feel free to
explore their purposes through online help or the Entity Arrivals models in the SMARTs
library.
2
in the Value field of the Time Between Arrivals section.
Initiate Mortgage Application
Application
.
.
12
2 • GETTING STARTED
What are entities?
Entities are the items—customers, documents, parts—that are being served, produced,
or otherwise acted on by your process. In business processes, they often are documents
or electronic records (checks, contracts, applications, purchase orders). In service
systems, entities usually are people (the customers being served in a restaurant, hospital,
airport, etc.). Manufacturing models typically have some kind of part running through the
process, whether it’s raw material, a subcomponent, or finished product. Other models
might have different types of entities, such as data packets in network analysis or letters
and boxes in package-handling facilities.
You may have different types of entities in the same model. For example, customers
moving through a check-in counter at an airport might be separated into regular, firstclass, and priority entity types. In some cases, entity types might be of an altogether
different form rather than classifications of some basic type. For instance, in a pharmacy,
prescriptions would be modeled as entities, running through the process of being filled. At
the same time, customers might be competing for the pharmacist’s attention with medical
inquiries; they would also be modeled as entities.
Review application (Process module)
Remember that as we create the flowchart, we’re looking at the process from the perspective of the entity. The Create module is a starting point for an entity’s flow through the
system being modeled. Next, in our case, the application will be reviewed for completeness by a Mortgage Review Clerk. Because this will take some amount of time, holding
the entity at this point in the flowchart for a delay and requiring a resource to perform the
activity, we use a Process module. We’ll call this process Review Application.
• • • • •
2 • Getting Started
Appendix A
describes the
distributions
available in Arena.
For the time delay, we also want to capture the natural variability that exists in most
processes. Very often, for work done by people or equipment, a triangular distribution
provides a good approximation. You specify the minimum time in which the work could
be done, the most likely value for the time delay, and the maximum duration of the process.
During the simulation run, each time an entity enters the process, Arena will calculate a
sample from the distribution information you’ve provided—in our case, a triangular
distribution. Over the course of a long simulation run where thousands of individual
samples are taken, the times will follow the profile illustrated next.
13
ARENA USER’S GUIDE
• • • • •
For our Review Application process, we’ll use a minimum time of 1 hour, most likely
value of 1.75 hours, and a maximum of 3 hours. We will assign a resource, the Mortgage
Review Clerk, to perform this process.
If more than one
resource is required
for a process to be
performed, add as
many as are
necessary in the
Process dialog’s
Resources list. An
entity won’t
commence its
process delay until
all listed resources
are available.
1. Double-click the Process module to open its property dialog box.
2. In the Name field, type Review Application.
3. To define a resource to perform this process, pull down the Action list and select Seize Delay Release.
Arriving entities will wait their turn for the resource to be available. When its turn
comes, the entity will seize the resource, delay for the process time, and then release
the resource to do other work.
4. A list of resources will appear in the center of the dialog box. To add a resource for
this process, click Add.
14
2 • GETTING STARTED
• • • • •
5. In the Resource Name field of the Resource dialog box, type
.
Clerk
Mortgage Review
6. Click OK to close the Resource dialog box.
7. Define the process delay parameters in the Minimum, Most Likely Value, and Maximum fields as
1, 1.75
, and 3. (Note that the default delay type is Triangular and the
default time units are in hours.)
8. Click OK to close the dialog box.
For now, we’ll leave the default values for the other Process module properties. Feel
free to explore their purposes through online help or the “Modeling Concepts” and
“Resources” models in the SMARTs library.
Complete? (Decide module)
After the mortgage application has been reviewed, we determine whether to accept or
return the application. In Arena, whenever an entity selects among branches in the process
logic, taking just one of the alternatives, a Decide module is used.
2 • Getting Started
When you use a
2-way Decide
module, the entity
that enters the
module leaves via
one of the two exit
points. If you want to
make copies of an
entity to model
parallel processes,
use a Separate
module.
For the mortgage application process, we’ll use a simple probability to determine the outcome of the decision, with 88% of applications accepted as complete.
1. Double-click the Decide module to open its property dialog box.
2. In the Name field, type
Complete?
.
15
ARENA USER’S GUIDE
• • • • •
3. For the Percent True field, type 88 to define the percent of entities that will be treated
with a “True” decision (i.e., will depart through the exit point at the right of the Decide
module).
4. Click OK to close the dialog box.
Accepted, Returned (Dispose module)
In our simple process for reviewing mortgage applications, all the work that we’re interested in is done. Now, we’ll remove the mortgage applications from the model, terminating the process with a Dispose module. Because there are two possible outcomes of the
mortgage application process—applications can be accepted or returned—we’re using
two Dispose modules that will count the number of applications under each outcome.
1. Double-click the first Dispose module (connected to the True condition branch of the
Decide module) to open its property dialog box, and in the Name field, type
Accepted
.
16
2. Click OK to close the dialog box.
3. Double-click the other Dispose module to open its property dialog box. In the Name
field, type
Returned
.
4. Click OK to close the dialog box.
• • • • •
2 • GETTING STARTED
2 • Getting Started
You can edit the
fields for any
module using
Arena’s spread-
sheet, including
flowchart modules.
Just click on the
icon in the Basic
Process panel to
display its
spreadsheet.
Mortgage review clerk (Resource module)
Along with our flowchart, we also can define parameters associated with other elements
of our model, such as resources, entities, queues, etc. For the mortgage process, we’ll
simply define the cost rate for the Mortgage Review Clerk so that our simulation results
will report the cost associated with performing this process. The clerk’s costs are fixed at
$12 per hour.
To provide these parameters to the Arena model, you’ll enter them in the Resources
spreadsheet.
1. In the Basic Process panel, click the Resource icon to display the Resources spreadsheet.
2. Because we defined the Mortgage Review Clerk as the resource in the Review
Application process, Arena has automatically added a resource with this name in the
Resources spreadsheet. Click in the Busy/Hour cell and define the cost rate when the
12
clerk is busy by typing
12
typing
.
. Click in the Idle/Hour cell and assign the idle cost rate by
17
ARENA USER’S GUIDE
• • • • •
Prepare for the simulation
To make the model ready for simulation, we’ll specify general project information and the
duration of the simulation run. Since we’re just testing our first-cut model, we’ll perform
a short, 20-day run.
1. Open the Project Parameters dialog box by using the Run > Setup menu item and
clicking the Project Parameters tab. In the Project Title field, type Mortgage ReviewAnalysis; we’ll leave the Statistics Collection check boxes as the
defaults, with Entities, Queues, Resources, and Processes checked and also check the
costing box.
2. Next, click the Replication Parameters tab within the same Run Setup dialog box. In
the Replication Length field, type 20; and in the Time Units field directly to the right
of Replication Length, select days from the drop-down list. Click OK to close the
dialog box.
18
Save the simulation model
Now that you’ve done some work on your model, it seems like a good time to save it.
Click Save on the Standard toolbar or select the File > Save menu item. Arena will
prompt you for a destination folder and file name. Browse to the target folder in which
you want to save the model (e.g., C:\My Documents) and type a name (e.g., Mortgage Review) in the file name field.
Arena’s model files store all of the model definition, including the flowchart, other graphics you’ve drawn, and the module data you entered. When you perform a simulation run,
the results are stored in a database using the same name as the model file.
Simulate the process
With these few, short steps, we are ready to predict the future! The mortgage application
model contains all of the information needed to run the simulation.
Start the simulation run by clicking the Go button or clicking the Run > Go menu item.
Arena first will check to determine whether you’ve defined a valid model, then will
launch the simulation.
If Arena displays an
error message, you
can use the Find
button in the error
window to locate the
source of the
problem. You can
change between the
error and model
windows by
selecting them from
the Window menu.
• • • • •
2 • GETTING STARTED
As the simulation progresses, you’ll see small entity pictures resembling pages moving
among the flowchart shapes. Also, a variety of variables change values as entities are
created and processed, as illustrated below.
Create: Number of Decide: Number of
entities createdentities out each branch
2 • Getting Started
Process: Number of entities
currently in process
Dispose: Number of
entities disposed
The animation scale
factor is the amount
of simulated time
between successive
screen updates.
Smaller values
provide smoother,
slower animation.
If the run finishes
before you have a
chance to explore
these controls,
answer No when
you’re asked if you
want to view the
results. Then click
Start Over on the
Run toolbar to begn
the run again.
If the animation is moving too fast, you can slow it down by adjusting the animation scale
factor. For this, you have two choices:
Open the Run Setup dialog box via the Run > Speed > Animation Speed Factor
menu item and enter a smaller value (e.g., 0.005) for the scale factor; or
Use the less-than (<) key during the run to decrease the scale factor by 20%. Be sure
that the model window is active—not the Navigate panel—or > and < won’t take
effect. Pressing < repeatedly is an easy way to fine tune the animation speed. The
greater-than (>) key speeds up animation by 20%.
Use the slider bar in the main toolbar. Move the slider to the left to slow down the ani-
mation; move the slider to the right to speed up the animation..
To pause the simulation, click the Pause button or press the Esc key. With the automatic
flowchart animation, you can see how many entities have been created, are currently in
the Review Application process, have left each branch of our Decide module, and have
left the model at each of our terminating Dispose modules. These variables can be helpful
in verifying the model. For example, if the probability in the Decide shape was entered
incorrectly (e.g., if you typed 12—the rejection probability—instead of 88), the variables
would show that many more applications were leaving the Returned branch.
19
ARENA USER’S GUIDE
• • • • •
View simulation reports
Each of Arena’s
reports is
displayed in its
own window within
the Arena
application. You
can use the
standard
window options
(maximize,
minimize, etc.) by
clicking on the
window control
buttons or by
pulling down the
window menu.
You also can step through the simulation one event at a time. Pause the simulation, then
click the Step button or press the F10 key. Each time you step the simulation, an entity is
moved through the flowchart. Usually, you’ll see animation of the entity’s movement,
though sometimes no visual change will take place (e.g., when the next event is creating a
new entity). When this occurs, just step again to move forward to the next event.
After you’ve watched some of the animated flowchart, you can quickly run to the end of
the simulation to view reports. Pause the simulation, then click the Fast Forward button
to run the simulation without updating the animation.
At the end of the run, Arena will ask whether you’d like to view reports. Click Ye s, and
the default report (the Category Overview Report) will be displayed in a report window,
as shown below.
20
On the left side of each report window is a tree listing the types of information available in
the report. The project name (in our case, Mortgage Review) is listed at the top of the tree,
followed by an entry for each category of data. This report summarizes the results across
all replications (although, in this model, we have only one replication). Other reports
provide detail for each replication.
2 • GETTING STARTED
By clicking on the entries inside the category sections, you can view various types of
results from the simulation run. The following table illustrates some of the questions you
could answer from the Category Overview Report on our simple mortgage application
process simulation.
QuestionReport SectionAnswer
• • • • •
On average, how long did mortgage
applications spend in the modeled
process?
What was the average cost of reviewing
a mortgage application?
What was the longest time an application
spent in review?
What was the maximum number of
applications waiting for review?
What proportion of time was the
Mortgage Review Clerk busy?
After you’ve browsed the Category Overview Report, you can close it by clicking on the
window icon to the left of the File menu and clicking Close. You can look at other reports
by clicking on their icons in the Project Bar. Each report will be displayed in its own
window. To return to the model window, close all of the report windows or select the
model file from the Window menu.
After you have viewed the reports and returned to the model window, end the Arena run
session by clicking the End button.
Enhance the visualization process
Now that we’ve completed the basic steps for analyzing the mortgage application process,
we can return to our model and embellish the graphical animation to gain further insight
into the process dynamics. Animation also can be of great benefit in enticing others in the
organization to be interested in process improvement.
Total Time (Entity), Average
column
Total Cost (Entity), Average
column
Total Time (Process), Maximum
column
Number Waiting (Queue),
Maximum column
Utilization (Resource), Average
column
16.51 hrs
2 • Getting Started
$22.99
33.45 hrs
21 applications
97%
We’ll add two animation components to the mortgage model. First, we’ll show our
Mortgage Review Clerk working at a desk, either busy or idle. To gain a better sense of
how many applications are waiting in the Review Application process over time, we’ll
also add a dynamic plot of the work-in-process (WIP) simulation variable. Our Arena
model will appear as shown below after we add these two objects.
21
ARENA USER’S GUIDE
• • • • •
Note: You can toggle between the split view (flowchart and spreadsheet) and a full-screen view
of either area by clicking the Split Screen toolbar button or selecting the View > Split Screen
menu item. When in full-screen view, clicking the icons on the Basic Process panel displays the
appropriate view (flowchart for flowchart modules and spreadsheet for data-only modules).
22
Loading...
+ 122 hidden pages
You need points to download manuals.
1 point = 1 manual.
You can buy points or you can get point for every manual you upload.