RUL prediciton

2 replies [Last post]
dtobonme
dtobonme's picture
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Joined: 2009-06-03

Hi,

How long must be the prognostic horizon to estimate the RUL? And can you explain how to use the "leave-one-out cross-validation" to evaluate the performance of the method ? because i don't see how to use this technique to evaluate multistep-ahead predictions necessary to estimate the future wear or failure state.

Thank you,

eklund
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Joined: 2009-05-14
leave-one-out

The RUL estimate is implicit. You generate an estimated maximum wear for any flute, and when it crosses a fixed (and unknown to you) threshold, the tool is finished.

Leave one out (LOO) is a method of cross validation:
http://en.wikipedia.org/wiki/Cross-validation_%28statistics%29

There are at least two ways to partition the data. You might train on two runs and evaluate on the third. Alternatively, you might train on two flutes within a run and evaluate on the third flute within a run.

But you are not obliged to use cross validation! If you have an approach you think will work better, use that...

vsotiris
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Joined: 2009-07-30
on definition of RUL

Regarding RUL,

Can you clarify what you mean by: "The RUL estimate is implicit".

I am under the impression that RUL is the number of cuts remaining until failure, given a fixed failure threshold, and given survival up until a certain earlier cut.

For example, given observed data from a test tool, up until say the 100th cut, then ask the question: what is the remaining useful life? Or alternatively, how many more cuts until failure?

Thanks

 
 
 

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