Page 316 - ExtendSim User Guide
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Activity-Based Costing
How ExtendSim tracks costs
Item block lists the costs of the items sorted by the Type attribute. As an item passes through the block, the row corresponding to the value of the Type attribute (1, 2, or 3) is updated.
Sort by Type model
Cost Stats block
The Cost Stats block is useful to determine which blocks are contributing the most to the total cost of the items being processed. See the help text of the block for a detailed description of how to use the Cost Stats block.
How ExtendSim tracks costs
☞ The previous sections discussed how to perform ABC in ExtendSim. This section provides a more detailed look at how ExtendSim tracks costs and is included mainly for informational purposes.
Setting the _cost and _rate attributes
When you define the cost or cost rate for a cost accumulator or resource (as discussed in “Defining costs and cost rates” on page 282), ExtendSim will assign the value to the appropri- ate costing system variable for that item. The fixed cost of the item is assigned to the _cost attribute and the variable cost rate is assigned to the _rate attribute.
Combining resources with cost accumulators
Whether you use the resource item and batching method or the resource pools method to model resources, two things happen when a resource is attached to a cost accumulator:
1) Thevalueoftheresource’sfixedcostisautomaticallyaddedtothecostaccumulator’s _cost attribute.
If using the batching method, the resource’s fixed cost comes from the resource’s _cost attri- bute. If using resource pools, the resource’s fixed cost comes from the Cost per use dialog item of the corresponding Resource Pool block.
2) Theresource’svariablecostrateandthenumberofresourcesusedarestoredinaninternal program structure called the cost array.
The cost array stores costing information for each cost accumulator in the model. ExtendSim uses the data in the cost array to calculate the time-based cost contributed by any resources that are combined with the cost accumulator. If using the batching method, the resource’s variable cost rate comes from the resources _rate attribute. If using resource pools, the resource’s vari-
Discrete Event

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