Template:Weibull++ Equation Fit Solver Example

Weibull++ Equation Fit Solver Example

Equation Fit Solver can be used to do linear and nonlinear regression. Assume an engineer collected the following degradation data.

Time	Reading
5	8.08
10	13.52
15	21.86
20	31.96
25	37.86
30	46.67
35	53.35
40	62.29
45	71.62
50	80.37
55	91.43
60	104.00

From the physical mechanism, the engineer knows the degradation path follows the following equation:

[math]\displaystyle{ y=a+bx+c\ln (x) }[/math]

where:

• x is the time

• y is the degradation reading.

This above model is not a standard degradation model in Webul++. It can be solved using the equation fit solver.

Solution:

Step 1: Create an Equation Fit Solver Folio

Step 2: Enter the above data into the folio

Step 3: Enter the user defined degradation function at the control panel and name it “My Degradation Equation”.

Step 4: Calculate it and the results are:

Step 5: You can use the “Calculate Y given X” to make prediction. For example, the predicted Y value at X=100 is 176.2424.

'Step 6: The plot of the fitted model and the observed values are given as: