10.5 – Resource-Related Techniques
10.5.1 – Using a Resource at an Activity
A resource (employee, machine, etc.) is used at an activity to perform the activity.
Suggested Technique
1. Create the activity where the resource will be used.
2. Create the resource. (Be sure that the Object Type field in the properties dialog indicates Resource.)
3. Connect the resource to the activity.
Alternatively, you may use the GET and FREE statements in the Action logic of the activity. Connected resources will always be captured before resources specified in a GET statement. On the other hand, resource connections that free a resource occur after any Action logic for the activity.
TO DO: Create the resource and connect it to the activity as shown above.
For simple situations like the previous one, it may not be necessary to model the resource unless there are times when it is unavailable due to other activities requiring its use, since it would probably be of no interest to the modeler.
To learn more about resources, see Resources and Resource Assignments.
10.5.2 – Using a Resource to Move Entities
Routing an entity with the use of a resource (employee, machine, etc.).
Suggested Technique
1. Create the routing connection where the resource will be used.
2. Create the resource. (Be sure that the Object Type field in the properties dialog indicates Resource .)
3. Connect the resource to the routing connection using the line tool.
Alternatively, you may use a GET statement in the Action logic of the routing connection and a FREE statement in the Action logic of the next activity. Connected resources will always be captured before resources specified in a GET statement. On the other hand, resource connections that free a resource occur after any Action logic for the routing or activity.
Example: Patients in a waiting room are escorted to a treatment room by a nurse.
TO DO: Connect the nurse (once created as above) to the appropriate routing.
To learn more about resources, see Resources and Resource Assignments.
10.5.3 – Keep a Resource throughout Multiple Activities
A resource is continuously used throughout a number of activities, including the moves from one activity to another. Useful in modeling resources such as case workers.
Suggested Technique
1. Connect the resource to the activity where the resource will first be used and select Get from the Type field in the properties dialog of the connection.
2. Connect the resource to the activity where the resource will last be used and select Free from the Type field in the properties dialog of the connection
Alternatively, you may use the GET and FREE statements in the Action logic of the appropriate activities. Connected resources will always be captured before resources specified in a GET statement. On the other hand, resource connections that free a resource occur after any Action logic for the activity.
Example: Incoming jobs to a copy center are received, copied, and invoiced all by the same clerk in three consecutive steps.
TO DO: Connect the clerk to the Receive activity and select Get from the Type field in the properties dialog. Then connect the clerk to the Invoice activity and select Free from the Type field in the properties dialog.
To learn more about resources, see Resources and Resource Assignments.
10.5.4 – Using Multiple Resources
Using more than one resource (employee, machine, etc.) to perform an activity.
Suggested Technique
1. Connect the resources to the activity or routing.
2. Make sure that each connection Type is either a Get or Get and Free.
Example: A dental treatment requires the use of a dentist and an assistant.
TO DO: Connect both resources to the activity.
Alternatively, you may use the GET or JOINTLYGET and FREE statements in the Action logic. Connected resources will always be captured before resources specified in a GET statement. On the other hand, resource connections that free a resource occur after any Action logic for the activity. If each resource is required for different lengths of time, use Get connections and specify the times followed by FREE statements in the activity Action logic. For example:
TIME(3.5 min)
FREE Doctor
TIME(5 min) // Nurse used for 5 additional minutes
FREE Nurse
10.5.5 – Using Alternate Resources
Designating a resource to use as an alternate if the primary resource assigned to the activity or move is unavailable.
Suggested Technique
1. Connect the primary resource to the activity or routing.
2. Connect the alternate resource to the primary resource connection.
Alternative resources may also be captured using the GET or JOINTLYGET statement with the OR operator. Connected resources will always be captured before resources specified in a GET statement. On the other hand, resource connections that free a resource occur after any Action logic for the activity.
Example: Normally the loan officer will help the customer with the loan application at the Application activity, but if no loan officers are available, a customer service representative can take the loan application.
TO DO: Connect the Service Rep (the alternate resource) to the assignment connection between the Loan Officer and the Application activity as shown above.
To learn more, see Resources and Resource Assignments.
If you use a GET connection (instead of a GET & FREE) to capture a resource and then connect an alternate resource to that connection, you must connect a free connection to both the primary and alternate resources when the resource is freed. One free connection is then executed and the others are ignored; the correct resource is freed without you knowing which one was captured.
10.5.6 – Determining the Resource Being Used
When an alternate resource is captured by an entity and a decision or activity time depends on which resource was captured, the OwnedResource function may be used to determine which resource was captured.
Suggested Technique
1. In the action logic of the activity or routing, use the OwnedResource() function without a number between the parentheses to test the name of the most recently captured resource.
2. Execute the appropriate action based on the name returned by the OwnedResource() function.
Alternatively, you may use the GET statement with an OR separating the alternate resources in the Action logic to capture the resources, and then use the OwnedResource() function to determine the captured resource. Connected resources will always be captured before resources specified in a GET statement. On the other hand, resource connections that free a resource occur after any Action logic for the activity.
Example: A receptionist usually answers the phone, but if the receptionist is busy, the filing clerk will answer the phone. If the filing clerk answers the phone, the call lasts about 7 minutes, otherwise it takes about 5 minutes.
TO DO: In the Action logic of the Answer Phone activity, enter:
IF OwnedResource() = Clerk THEN TIME(7 min)
ELSE TIME(5 min)
To learn more about the OwnedResource() function, see OwnedResource(n).
10.5.7 – Prioritizing Resource Usage
When two different activities each have an entity waiting to use the same resource, one activity may have high