Page 210 - ExtendSim User Guide
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184 Processing
Setting the processing time
processing time will then be normally distributed and the Activity block will process each item for approximately 2 time units.
Random Activity model
For more information, see “Constant values and random variables” on page 60, “Random numbers” on page 703, and “Probability distributions” on page 704.
Custom processing time
Attributes can be used to specify how long a specific item will be processed. This is a very powerful feature since the Activity block can recognize each item’s processing time and behave accordingly.
Custom Time model
In the simplest case, set an item’s attribute value to the desired amount of processing time, then use the Activity block to read the attribute value and process the item for that period of time.
Custom Time model
The Custom Time model uses the Set block to set the value of an attribute called CheckTime to the amount of time it takes to check the item. Items that need a final check have a CheckTime attri- bute value of 5, for instance, and items that ship unchecked have an attribute value of 0. That value (0 or 5) is provided by the Random Number block (Value library) using an Empirical distribu- tion where 25% of the items have a value of 0 and 75% have a value of 5.
Custom processing time
All items then go through the checking step, easily represented by an Activity block. In its dia- log, this block indicates that the Delay is: an item’s attribute value and the attribute is CheckTime.
Discrete Event

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