RE: Way OT : Any maths bods around?

["christopher purves" <CHRIS_PURVES@xxxxxxx>]

Not in general for this type of distribution e.g an electric light bulb
follows this rule. I imagine an jet engine has a slightly different distro
as parts do need to be replaced every so often unlike the light bulb which
has no moving parts. This all comes full circle to knowing the underlying
distro for the engines.

Chris




----Original Message Follows----
From: "Hawes,Timothy Edward (GEG)" <haweste@xxxxxxx>
Reply-To: ukha_d@xxxxxxx
To: <ukha_d@xxxxxxx>
Subject: RE: [ukha_d] Way OT : Any maths bods around?
Date: Mon, 28 Feb 2005 14:21:57 -0000


I see. So do you also need to know how many hours have been flown since
the last service as that affects where you are in the distribution ?

Tim H.

> -----Original Message-----
> From: christopher purves
>
> Yep - just checked it with an ex. stats professor who works
> for me (really).
> He says most people assume exponential - resetting
> distributions for such things. You integrate the distro
> between 0 and 10 hours where the distro has a mtbf of 100,000
> hours. Of course there are 4 engines and you only need one!
> In fact, they glide fairly well also.
>
>
> ----Original Message Follows----
> From: "christopher purves"
>
> I would imagine you need to know the underlying distribution
> for this then integrate between 0 and 10 hours.
>
> Chris