Page 326 - ExtendSim User Guide

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Statistics and Model Metrics
Time weighted versus observed statistics
between 1 and 3 pounds. The model uses an attribute called Weight to track the weights of the separate parts.
Non-Processing Model
The Properties tab of the Batch block is set to sum the values of the Weight attribute for the completed assembly. After the parts are batched, an Equation(I) block increments the Weight attribute by 0.5 pounds. At the loading dock, the weight of the current item is displayed as it leaves.
Processing model
If the data to be accumulated is dependent on processing, you can accumulate values using a Holding Tank block (Value library) connected to the PT (process time) connector on an Activ- ity block. For example, to accumulate the total amount of processing time parts required, as an indication of when the processing equipment needs to be refurbished.
Processing model
In this model, each time an item leaves the Activity, its processing time will be added to the value in the Holding Tank.
Time weighted versus observed statistics
The Mean & Variance block (Value library) can calculate either a time weighted or observed statistic:
• IfUsetimeweightedstatisticsischeckedintheMean&Varianceblock,themean,vari- ance, and standard deviation are calculated by weighting the input value based on the simu- lation time. This is derived by dividing the input value by the duration of that input value and then summing these over the course of the simulation.
• IfUsetimeweightedstatisticsisnotchecked,thesumoftheinputvalueswillbedivided by the total number of input values received, resulting in an observed statistic.
Discrete Event
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