Repairable Systems Monte Carlo Utility

For reliability growth data analysis only.

Weibull++'s Repairable Systems Monte Carlo utility uses simulation to generate a single data set containing values that are distributed according to the Crow-AMSAA (NHPP) model with specified beta and lambda parameters.

To access the Monte Carlo utility, choose Home > Insert > Monte Carlo and choose the Repairable Systems Monte Carlo option.

The setup window will appear. Follow the steps outlined below to set up the simulation:

  1. On the Main tab of the window, select a data type and time units in the Data Type area. In the Parameters area, enter the beta and lambda values for the Crow-AMSAA model that will be used to generate the data set.
  2. In the Data Sets / Points area, enter the following information:
    • Specify the Number of systems for which data will be generated. This value is fixed at 1 unless you selected a multiple systems data type on the Main tab (i.e., Multiple Systems - Concurrent or Repairable Systems).
    • Use the Test termination field to specify what will determine the end of the observation period for the simulated data.
      • If the period will end after a specific number of failures have been observed, choose Failure Terminated from the drop-down list and enter the number of Failures in the next field.
      • If the observation period will end at a specific time, choose Time Terminated from the drop-down list and enter a Time in the next field.
    • If you selected to generate Grouped Failure Times data, click the Set Intervals link to open a window that allows you to specify the intervals that will contain the failures. You need at least three intervals to simulate this type of data.
  3. On the Settings tab, specify how you want to generate the data set and where you want the data to be stored.
    • Select the Use Seed check box if you would like to set a consistent starting point from which the random numbers will be generated. Using the same seed value and keeping all other settings the same will allow you to replicate your results.
    • In the Math Precision area, enter the number of decimal places that will be used for each simulated data point. (This does not affect the precision used in the calculated parameters and other results.)
    • Use the Generate Data in Specified Folio drop-down list to specify where to put the simulated data. If you select a folio that already exists in the project, the data will be placed into a new data sheet at the end of that folio, and any existing data sheets and plots will remain unchanged. If you choose <New Folio> the software will create a new folio to place the data into.
  4. After the simulation is set up, click Generate to create a new growth data folio data sheet populated with a data set that meets your specifications.

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