Well now.....if I read you correctly Sean this quote:
"In engineering design, for example, we design a part to withstand V amount of force, plus or minus W, X % of the time, with Y probability of failure after Z hours in service - there are no absolutes."
Is the formula for...."That looks about right"!
and explains this:
"Hobbyist projects are often impressive simply because they incorporate engineering overkill that you just don't see in commercial projects."
I have never seen it explained quite so clearly, and it would seem that, that is the common ground we share (amateurs) with you professionals.
Thanks Sean!
Joe
From: "Sean T. Stevenson" <cast55@telus.net>
Reply-To: personal_submersibles@psubs.org
To: personal_submersibles@psubs.org
Subject: Re: [PSUBS-MAILIST] TANK / PSI QUESTION
Date: Sun, 12 Feb 2006 21:20:02 -0500
>There is a common misconception by the layperson that engineering is
>a precise science. It it not, at least, not in the pure sense as
>with physics or mathematics. Engineering constitutes a method of
>using the aforementioned pure sciences to help make approximations
>about real-world phenomena, but it is still impossible to model any
>real-world system exhaustively, nor is it necessary. In engineering
>design, for example, we design a part to withstand V amount of
>force, plus or minus W, X % of the time, with Y probability of
>failure after Z hours in service - there are no absolutes. This is
>why we do tedious calculations to several decimal places to
>determine our best guess, and then overbuild by a safety factor of
>some integer, depending on how paranoid we are. The main difference
>between professionals and amateurs in this respect (apart from
>formal training) is that professionals are paid to produce designs
>that are as close to insufficient as possible, within the service
>requirements. Hobbyist projects are often impressive simply because
>they incorporate engineering overkill that you just don't see in
>commercial projects.
>
>-Sean
>
>
>Joseph Perkel wrote:
>
>>Now that...is what you call an *engineering analysis!*
>>
>>/"but also of concentric cross-section
>> >as you travel along its length. Anything outside of that is
>> >extranneous material, as far as the calculations are concerned"/
>>
>>That is what I find so impressive about engineering, the ability to
>>minimally design for the required stressors, and why amateurs like
>>myself have to overbuild a bit to feel good about it!
>>
>>Great job Sean!
>>
>>Joe
>>
>
>
>
>
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