Page 308 - ExtendSim User Guide
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Activity-Based Costing
Modeling with activity-based costing
Receive Inventory model
Receive Inventory model
Assume you want to determine the cost associated with receiving crated inventory at a ware- house. There is a one-time docking fee of $3.00 for every shipment that is received, and it costs $0.15 an hour any time the crate waits for processing (such as in the receiving area.)
As each shipment arrives, a labor resource takes an average of 30 minutes to unpack the crate and stock the contents on the appropriate shelves. In this case, the crate is being processed and is therefore the cost accumulator. The half-hour processing time and the hourly wage of the laborer is used to automatically calculate the cost of unpacking and shelving. That cost is then added to the accumulated cost being tracked with the crate. As the crate progresses through the steps of being received and unpacked, ExtendSim will add the cost incurred at each step to the accumulated cost.
As discussed in “Modeling resources” on page 223, resources can be modeled using resource pool blocks or by batching resources from a Resource Item block with other items. In the resource pool method, resource units act as constraints on the flow of items throughout the model. In the batching method, resource items are required to be batched with other items before the items can proceed to the next process.
Whether resource pool units or resource items, resources provide a service for the items in a model; they do not accumulate their own costs. Whenever a cost accumulator uses a resource, the resource’s cost rates are used to calculate costs which are then added to the total cost of the cost accumulator. (Cost rates are discussed on page 284.) For instance, in the Receive Inven- tory model described above, the laborer is a resource item that is batched with the crate. Since the laborer is a resource, it will not accumulate its own cost. Rather, the cost rate of the laborer (the hourly wage), and the time it takes the laborer to unload the crate, is used to automatically calculate the cost of unpacking the crate.
☞ The default is that the Resource Item block outputs resource items. However, you can select in the block’s Cost tab to output items as cost accumulators. This is discussed at “Resource Item block” on page 284.
Defining costs and cost rates
To include ABC in a model, simply enter information in the costing section of the dialogs of cost-aware blocks. There are two types of cost information:
Discrete Event

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