User's guide chapter 3 section 3 & 4

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3.3 – Activities

Activities are the tasks performed on entities—e.g., assembly, document approval or customer checkout. An activity is defined in terms of the activity time as well as any resource requirements. User-defined action logic may also be specified for an activity. Activities have a processing capacity and may have input and output queues associated with them. Resources connected to an activity are captured before the activity takes place and freed after it has ended.

3.3.1 – General

Properties dialog activity general ProcessModel software

Name The name of the activity (e.g. CheckIn).

Capacity The maximum number of entities (1 – 999,999) that can be processed concurrently (either individually or in batch). Scenario Parameters may be used in place of numeric values. INF may be used to represent the largest numeric value allowed (999,999).

Stats on This check box allows you to turn off statistics collection for individual activities in your model. By default, this option remains checked.

Time The time to perform the activity. Any expression including distributions, attributes, or variables may be entered as the time value. If a resource is connected to the activity, the resource is captured before the time is taken. Activity times may also be defined using TIME statements in the Action section of the dialog.

 If an entity is spending more time than expected at an activity where you are using action logic, you likely have time on the General tab AND in a TIME statement in your action logic. If you use a TIME statement in action logic, you should typically set the time on the General tab to 0. Otherwise you will first execute the time in the action logic. Then the time on the General tab will be executed. Thus your two time settings add together.

Input Queue Cap. The capacity of the input queue. The input queue is like a waiting area. If the input queue has available capacity, entities may be routed into it to wait until the activity has available capacity to process the entity. If the queue has no available capacity, entities must wait at the previous activity (or in that activity’s output queue) until capacity becomes available in the input queue or the activity (0–999,999). Scenario Parameters may be used in place of numeric values.

Output Queue Cap. The capacity of the output queue. The output queue is like a waiting area where entities will wait for available capacity at the intended destination (0–999,999). Scenario Parameters may be used in place of numeric values.

Object Type Allows the type of the object to be changed to something other than an activity. For instance, you may want to change an activity object into a storage or resource.

3.3.2 – Batching

The batching tab allows you to hold entities in queue until a specified quantity is reached. For example, parts might be held in front of a heat treating oven until a specified quantity is reached. The group of part is moved into the oven and the entire batch is heat treated for a specific time. The